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1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003 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 is 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
4282 complain)))
4283 /* We were unable to bind the arguments. */
4286 /* In the scope of a template class, explicit references to the
4287 template class refer to the type of the template, not any
4288 instantiation of it. For example, in:
4290 template <class T> class C { void f(C<T>); }
4292 the `C<T>' is just the same as `C'. Outside of the
4293 class, however, such a reference is an instantiation. */
4295 arglist))
4296 {
4300 {
4301 tree ctx;
4311 /* We're not in the scope of the class, so the
4312 TEMPLATE_TYPE is not the type we want after all. */
4314 found_ctx:;
4315 }
4316 }
4324 {
4327 /* Use the move-to-front heuristic to speed up future
4328 searches. */
4335 }
4337 /* This type is a "partial instantiation" if any of the template
4338 arguments still involve template parameters. Note that we set
4339 IS_PARTIAL_INSTANTIATION for partial specializations as
4340 well. */
4346 {
4351 }
4358 /* Create the type. */
4360 {
4362 {
4365 }
4366 else
4367 /* We don't want to call start_enum for this type, since
4368 the values for the enumeration constants may involve
4369 template parameters. And, no one should be interested
4370 in the enumeration constants for such a type. */
4372 }
4373 else
4374 {
4381 /* A local class. Make sure the decl gets registered properly. */
4384 }
4386 /* If we called start_enum or pushtag above, this information
4387 will already be set up. */
4389 {
4397 }
4398 else
4406 /* Set up the template information. We have to figure out which
4407 template is the immediate parent if this is a full
4408 instantiation. */
4411 /* This case is easy; there are no member templates involved. */
4413 else
4414 {
4415 /* This is a full instantiation of a member template. Look
4416 for a partial instantiation of which this is an instance. */
4420 {
4424 /* We only want partial instantiations, here, not
4425 specializations or full instantiations. */
4430 /* Temporarily reduce by one the number of levels in the
4431 ARGLIST and in FOUND so as to avoid comparing the
4432 last set of arguments. */
4436 /* See if the arguments match. If they do, then TMPL is
4437 the partial instantiation we want. */
4440 /* Restore the argument vectors to their full size. */
4445 {
4448 }
4449 }
4452 {
4453 /* There was no partial instantiation. This happens
4454 where C<T> is a member template of A<T> and it's used
4455 in something like
4457 template <typename T> struct B { A<T>::C<int> m; };
4458 B<float>;
4460 Create the partial instantiation.
4461 */
4465 }
4466 }
4475 /* Now that the type has been registered on the instantiations
4476 list, we set up the enumerators. Because the enumeration
4477 constants may involve the enumeration type itself, we make
4478 sure to register the type first, and then create the
4479 constants. That way, doing tsubst_expr for the enumeration
4480 constants won't result in recursive calls here; we'll find
4481 the instantiation and exit above. */
4484 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4485 is set up. */
4489 /* If the type makes use of template parameters, the
4490 code that generates debugging information will crash. */
4494 }
4496 }
4497 \f
4498 struct pair_fn_data
4499 {
4500 tree_fn_t fn;
4502 htab_t visited;
4503 };
4505 /* Called from for_each_template_parm via walk_tree. */
4507 static tree
4509 {
4520 {
4524 /* Fall through. */
4536 /* Since we're not going to walk subtrees, we have to do this
4537 explicitly here. */
4541 /* Fall through. */
4544 /* Check the return type. */
4548 /* Check the parameter types. Since default arguments are not
4549 instantiated until they are needed, the TYPE_ARG_TYPES may
4550 contain expressions that involve template parameters. But,
4551 no-one should be looking at them yet. And, once they're
4552 instantiated, they don't contain template parameters, so
4553 there's no point in looking at them then, either. */
4554 {
4555 tree parm;
4562 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4563 want walk_tree walking into them itself. */
4565 }
4580 /* Fall through. */
4595 /* Record template parameters such as `T' inside `TT<T>'. */
4598 /* Fall through. */
4610 /* A template template parameter is encountered. */
4615 /* Already substituted template template parameter */
4636 /* If there's no type, then this thing must be some expression
4637 involving template parameters. */
4657 /* If we do not handle this case specially, we end up walking
4658 the BINFO hierarchy, which is circular, and therefore
4659 confuses walk_tree. */
4668 }
4670 /* We didn't find any template parameters we liked. */
4672 }
4674 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4675 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4676 call FN with the parameter and the DATA.
4677 If FN returns nonzero, the iteration is terminated, and
4678 for_each_template_parm returns 1. Otherwise, the iteration
4679 continues. If FN never returns a nonzero value, the value
4680 returned by for_each_template_parm is 0. If FN is NULL, it is
4681 considered to be the function which always returns 1. */
4683 static int
4685 {
4689 /* Set up. */
4693 /* Walk the tree. (Conceptually, we would like to walk without
4694 duplicates, but for_each_template_parm_r recursively calls
4695 for_each_template_parm, so we would need to reorganize a fair
4696 bit to use walk_tree_without_duplicates, so we keep our own
4697 visited list.) */
4700 else
4702 NULL);
4704 for_each_template_parm_r,
4708 /* Clean up. */
4713 }
4715 /* Returns true if T depends on any template parameter. */
4717 int
4719 {
4721 }
4723 /* Returns true if T depends on any template parameter with level LEVEL. */
4725 int
4727 {
4729 }
4733 #ifdef GATHER_STATISTICS
4735 #endif
4739 /* We're starting to instantiate D; record the template instantiation context
4740 for diagnostics and to restore it later. */
4742 int
4744 {
4748 {
4749 /* If the instantiation in question still has unbound template parms,
4750 we don't really care if we can't instantiate it, so just return.
4751 This happens with base instantiation for implicit `typename'. */
4756 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4762 }
4769 #ifdef GATHER_STATISTICS
4772 #endif
4776 }
4778 /* We're done instantiating this template; return to the instantiation
4779 context. */
4781 void
4783 {
4786 /* Restore the filename and line number stashed away when we started
4787 this instantiation. */
4795 }
4797 /* We're instantiating a deferred template; restore the template
4798 instantiation context in which the instantiation was requested, which
4799 is one step out from LEVEL. */
4801 static void
4803 {
4804 tree t;
4812 }
4814 /* Return the outermost template instantiation context, for use with
4815 -falt-external-templates. */
4817 tree
4819 {
4824 ;
4826 }
4828 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4829 vector of template arguments, as for tsubst.
4831 Returns an appropriate tsubst'd friend declaration. */
4833 static tree
4835 {
4836 tree new_friend;
4844 /* This was a friend declared with an explicit template
4845 argument list, e.g.:
4847 friend void f<>(T);
4849 to indicate that f was a template instantiation, not a new
4850 function declaration. Now, we have to figure out what
4851 instantiation of what template. */
4852 {
4854 tree new_args;
4855 tree tmpl;
4858 /* Friend functions are looked up in the containing namespace scope.
4859 We must enter that scope, to avoid finding member functions of the
4860 current cless with same name. */
4875 }
4879 /* The NEW_FRIEND will look like an instantiation, to the
4880 compiler, but is not an instantiation from the point of view of
4881 the language. For example, we might have had:
4883 template <class T> struct S {
4884 template <class U> friend void f(T, U);
4885 };
4887 Then, in S<int>, template <class U> void f(int, U) is not an
4888 instantiation of anything. */
4894 {
4898 }
4900 /* The mangled name for the NEW_FRIEND is incorrect. The function
4901 is not a template instantiation and should not be mangled like
4902 one. Therefore, we forget the mangling here; we'll recompute it
4903 later if we need it. */
4905 {
4908 }
4911 {
4912 tree old_decl;
4913 tree new_friend_template_info;
4914 tree new_friend_result_template_info;
4915 tree ns;
4918 /* We must save some information from NEW_FRIEND before calling
4919 duplicate decls since that function will free NEW_FRIEND if
4920 possible. */
4923 {
4924 /* This declaration is a `primary' template. */
4927 new_friend_is_defn
4929 new_friend_result_template_info
4931 }
4932 else
4933 {
4936 }
4938 /* Inside pushdecl_namespace_level, we will push into the
4939 current namespace. However, the friend function should go
4940 into the namespace of the template. */
4947 {
4948 /* This new friend declaration matched an existing
4949 declaration. For example, given:
4951 template <class T> void f(T);
4952 template <class U> class C {
4953 template <class T> friend void f(T) {}
4954 };
4956 the friend declaration actually provides the definition
4957 of `f', once C has been instantiated for some type. So,
4958 old_decl will be the out-of-class template declaration,
4959 while new_friend is the in-class definition.
4961 But, if `f' was called before this point, the
4962 instantiation of `f' will have DECL_TI_ARGS corresponding
4963 to `T' but not to `U', references to which might appear
4964 in the definition of `f'. Previously, the most general
4965 template for an instantiation of `f' was the out-of-class
4966 version; now it is the in-class version. Therefore, we
4967 run through all specialization of `f', adding to their
4968 DECL_TI_ARGS appropriately. In particular, they need a
4969 new set of outer arguments, corresponding to the
4970 arguments for this class instantiation.
4972 The same situation can arise with something like this:
4974 friend void f(int);
4975 template <class T> class C {
4976 friend void f(T) {}
4977 };
4979 when `C<int>' is instantiated. Now, `f(int)' is defined
4980 in the class. */
4983 /* On the other hand, if the in-class declaration does
4984 *not* provide a definition, then we don't want to alter
4985 existing definitions. We can just leave everything
4986 alone. */
4987 ;
4988 else
4989 {
4990 /* Overwrite whatever template info was there before, if
4991 any, with the new template information pertaining to
4992 the declaration. */
4998 old_decl);
4999 else
5000 {
5001 tree t;
5002 tree new_friend_args;
5011 {
5017 }
5019 /* Now, since specializations are always supposed to
5020 hang off of the most general template, we must move
5021 them. */
5024 {
5029 }
5030 }
5031 }
5033 /* The information from NEW_FRIEND has been merged into OLD_DECL
5034 by duplicate_decls. */
5036 }
5037 }
5039 {
5040 /* Check to see that the declaration is really present, and,
5041 possibly obtain an improved declaration. */
5047 }
5049 done:
5052 }
5054 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5055 template arguments, as for tsubst.
5057 Returns an appropriate tsubst'd friend type or error_mark_node on
5058 failure. */
5060 static tree
5062 {
5063 tree friend_type;
5064 tree tmpl;
5065 tree context;
5070 {
5073 else
5075 }
5077 /* First, we look for a class template. */
5080 /* But, if we don't find one, it might be because we're in a
5081 situation like this:
5083 template <class T>
5084 struct S {
5085 template <class U>
5086 friend struct S;
5087 };
5089 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5090 for `S<int>', not the TEMPLATE_DECL. */
5092 {
5095 }
5098 {
5099 /* The friend template has already been declared. Just
5100 check to see that the declarations match, and install any new
5101 default parameters. We must tsubst the default parameters,
5102 of course. We only need the innermost template parameters
5103 because that is all that redeclare_class_template will look
5104 at. */
5107 {
5108 tree parms;
5112 }
5115 }
5116 else
5117 {
5118 /* The friend template has not already been declared. In this
5119 case, the instantiation of the template class will cause the
5120 injection of this template into the global scope. */
5123 /* The new TMPL is not an instantiation of anything, so we
5124 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5125 the new type because that is supposed to be the corresponding
5126 template decl, i.e., TMPL. */
5133 /* Inject this template into the global scope. */
5135 }
5138 {
5141 else
5143 }
5146 }
5148 /* Returns zero if TYPE cannot be completed later due to circularity.
5149 Otherwise returns one. */
5151 static int
5153 {
5163 else
5165 }
5167 tree
5169 {
5171 tree typedecl;
5172 tree pbinfo;
5182 /* Figure out which template is being instantiated. */
5186 /* Figure out which arguments are being used to do the
5187 instantiation. */
5190 /* Determine what specialization of the original template to
5191 instantiate. */
5194 {
5199 {
5201 {
5204 }
5205 }
5208 }
5212 else
5215 /* If the template we're instantiating is incomplete, then clearly
5216 there's nothing we can do. */
5220 /* If we've recursively instantiated too many templates, stop. */
5224 /* Now we're really doing the instantiation. Mark the type as in
5225 the process of being defined. */
5228 /* We may be in the middle of deferred access check. Disable
5229 it now. */
5235 {
5236 /* This TYPE is actually an instantiation of a partial
5237 specialization. We replace the innermost set of ARGS with
5238 the arguments appropriate for substitution. For example,
5239 given:
5241 template <class T> struct S {};
5242 template <class T> struct S<T*> {};
5244 and supposing that we are instantiating S<int*>, ARGS will
5245 present be {int*} but we need {int}. */
5246 tree inner_args
5248 args);
5250 /* If there were multiple levels in ARGS, replacing the
5251 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5252 want, so we make a copy first. */
5254 {
5257 }
5258 else
5260 }
5264 /* Set the input location to the template definition. This is needed
5265 if tsubsting causes an error. */
5295 #ifdef ENABLE_CHECKING
5299 /* We should never instantiate a nested class before its enclosing
5300 class; we need to look up the nested class by name before we can
5301 instantiate it, and that lookup should instantiate the enclosing
5302 class. */
5304 #endif
5307 {
5314 /* We must enter the scope containing the type, as that is where
5315 the accessibility of types named in dependent bases are
5316 looked up from. */
5319 /* Substitute into each of the bases to determine the actual
5320 basetypes. */
5322 {
5323 tree base;
5324 tree access;
5325 tree pbase;
5330 /* Substitute to figure out the base class. */
5337 }
5339 /* The list is now in reverse order; correct that. */
5342 /* Now call xref_basetypes to set up all the base-class
5343 information. */
5347 }
5349 /* Now that our base classes are set up, enter the scope of the
5350 class, so that name lookups into base classes, etc. will work
5351 correctly. This is precisely analogous to what we do in
5352 begin_class_definition when defining an ordinary non-template
5353 class. */
5356 /* Now members are processed in the order of declaration. */
5359 {
5363 {
5365 {
5366 /* Build new CLASSTYPE_NESTED_UTDS. */
5370 tree newtag;
5375 {
5377 /* Unfortunately, lookup_template_class sets
5378 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5379 instantiation (i.e., for the type of a member
5380 template class nested within a template class.)
5381 This behavior is required for
5382 maybe_process_partial_specialization to work
5383 correctly, but is not accurate in this case;
5384 the TAG is not an instantiation of anything.
5385 (The corresponding TEMPLATE_DECL is an
5386 instantiation, but the TYPE is not.) */
5389 /* Now, we call pushtag to put this NEWTAG into the scope of
5390 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5391 pushtag calling push_template_decl. We don't have to do
5392 this for enums because it will already have been done in
5393 tsubst_enum. */
5397 }
5398 }
5401 {
5402 /* Build new TYPE_METHODS. */
5403 tree r;
5413 }
5414 else
5415 {
5416 /* Build new TYPE_FIELDS. */
5419 {
5420 tree r;
5422 /* The the file and line for this declaration, to
5423 assist in error message reporting. Since we
5424 called push_tinst_level above, we don't need to
5425 restore these. */
5434 {
5435 tree init;
5440 else
5443 finish_static_data_member_decl
5448 }
5450 {
5451 /* Determine whether R has a valid type and can be
5452 completed later. If R is invalid, then it is
5453 replaced by error_mark_node so that it will not be
5454 added to TYPE_FIELDS. */
5460 {
5463 }
5464 }
5466 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5467 such a thing will already have been added to the field
5468 list by tsubst_enum in finish_member_declaration in the
5469 CLASSTYPE_NESTED_UTDS case above. */
5473 {
5476 }
5477 }
5478 }
5479 }
5480 else
5481 {
5483 {
5484 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5487 tree new_friend_type;
5496 else
5497 {
5500 /* The call to xref_tag_from_type does injection for friend
5501 classes. */
5503 new_friend_type =
5506 }
5509 /* Trick make_friend_class into realizing that the friend
5510 we're adding is a template, not an ordinary class. It's
5511 important that we use make_friend_class since it will
5512 perform some error-checking and output cross-reference
5513 information. */
5522 }
5523 else
5524 {
5525 /* Build new DECL_FRIENDLIST. */
5526 tree r;
5534 }
5535 }
5536 }
5538 /* Set the file and line number information to whatever is given for
5539 the class itself. This puts error messages involving generated
5540 implicit functions at a predictable point, and the same point
5541 that would be used for non-template classes. */
5548 /* Clear this now so repo_template_used is happy. */
5552 /* Now that the class is complete, instantiate default arguments for
5553 any member functions. We don't do this earlier because the
5554 default arguments may reference members of the class. */
5558 /* Implicitly generated member functions will not have template
5559 information; they are not instantiations, but instead are
5560 created "fresh" for each instantiation. */
5573 }
5575 static tree
5577 {
5578 tree r;
5584 else
5585 {
5589 {
5590 /* Sometimes, one of the args was an expression involving a
5591 template constant parameter, like N - 1. Now that we've
5592 tsubst'd, we might have something like 2 - 1. This will
5593 confuse lookup_template_class, so we do constant folding
5594 here. We have to unset processing_template_decl, to fool
5595 tsubst_copy_and_build() into building an actual tree. */
5597 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5598 as simple as it's going to get, and trying to reprocess
5599 the trees will break. Once tsubst_expr et al DTRT for
5600 non-dependent exprs, this code can go away, as the type
5601 will always be set. */
5603 {
5610 }
5612 }
5613 }
5615 }
5617 /* Substitute ARGS into the vector or list of template arguments T. */
5619 static tree
5621 {
5627 {
5629 tree new_arg;
5633 else
5642 }
5652 }
5654 /* Return the result of substituting ARGS into the template parameters
5655 given by PARMS. If there are m levels of ARGS and m + n levels of
5656 PARMS, then the result will contain n levels of PARMS. For
5657 example, if PARMS is `template <class T> template <class U>
5658 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5659 result will be `template <int*, double, class V>'. */
5661 static tree
5663 {
5671 {
5672 tree new_vec =
5677 {
5688 }
5694 }
5697 }
5699 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5700 type T. If T is not an aggregate or enumeration type, it is
5701 handled as if by tsubst. IN_DECL is as for tsubst. If
5702 ENTERING_SCOPE is nonzero, T is the context for a template which
5703 we are presently tsubst'ing. Return the substituted value. */
5705 static tree
5707 tree args,
5708 tsubst_flags_t complain,
5709 tree in_decl,
5711 {
5716 {
5721 /* Else fall through. */
5725 {
5726 tree argvec;
5727 tree context;
5728 tree r;
5730 /* First, determine the context for the type we are looking
5731 up. */
5737 /* Then, figure out what arguments are appropriate for the
5738 type we are trying to find. For example, given:
5740 template <class T> struct S;
5741 template <class T, class U> void f(T, U) { S<U> su; }
5743 and supposing that we are instantiating f<int, double>,
5744 then our ARGS will be {int, double}, but, when looking up
5745 S we only want {double}. */
5755 }
5756 else
5757 /* This is not a template type, so there's nothing to do. */
5762 }
5763 }
5765 /* Substitute into the default argument ARG (a default argument for
5766 FN), which has the indicated TYPE. */
5768 tree
5770 {
5771 /* This default argument came from a template. Instantiate the
5772 default argument here, not in tsubst. In the case of
5773 something like:
5775 template <class T>
5776 struct S {
5777 static T t();
5778 void f(T = t());
5779 };
5781 we must be careful to do name lookup in the scope of S<T>,
5782 rather than in the current class.
5784 ??? current_class_type affects a lot more than name lookup. This is
5785 very fragile. Fortunately, it will go away when we do 2-phase name
5786 binding properly. */
5788 /* FN is already the desired FUNCTION_DECL. */
5796 /* Make sure the default argument is reasonable. */
5800 }
5802 /* Substitute into all the default arguments for FN. */
5804 static void
5806 {
5807 tree arg;
5808 tree tmpl_args;
5812 /* If this function is not yet instantiated, we certainly don't need
5813 its default arguments. */
5818 arg;
5824 }
5826 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5827 (already computed) substitution of ARGS into TREE_TYPE (T), if
5828 appropriate. Return the result of the substitution. Issue error
5829 and warning messages under control of COMPLAIN. */
5831 static tree
5833 {
5834 location_t saved_loc;
5838 /* Set the filename and linenumber to improve error-reporting. */
5843 {
5845 {
5846 /* We can get here when processing a member template function
5847 of a template class. */
5849 tree spec;
5853 {
5854 /* We might already have an instance of this template.
5855 The ARGS are for the surrounding class type, so the
5856 full args contain the tsubst'd args for the context,
5857 plus the innermost args from the template decl. */
5861 tree full_args;
5866 /* tsubst_template_args doesn't copy the vector if
5867 nothing changed. But, *something* should have
5868 changed. */
5873 {
5876 }
5877 }
5879 /* Make a new template decl. It will be similar to the
5880 original, but will record the current template arguments.
5881 We also create a new function declaration, which is just
5882 like the old one, but points to this new template, rather
5883 than the old one. */
5889 {
5894 }
5903 {
5909 }
5910 else
5911 {
5920 }
5926 /* The template parameters for this new template are all the
5927 template parameters for the old template, except the
5928 outermost level of parameters. */
5931 complain);
5937 /* Record this non-type partial instantiation. */
5940 }
5944 {
5945 tree ctx;
5948 tree gen_tmpl;
5953 /* Nobody should be tsubst'ing into non-template functions. */
5957 {
5958 tree spec;
5961 /* If T is not dependent, just return it. We have to
5962 increment PROCESSING_TEMPLATE_DECL because
5963 value_dependent_expression_p assumes that nothing is
5964 dependent when PROCESSING_TEMPLATE_DECL is zero. */
5971 /* Calculate the most general template of which R is a
5972 specialization, and the complete set of arguments used to
5973 specialize R. */
5979 /* Check to see if we already have this specialization. */
5983 {
5986 }
5988 /* We can see more levels of arguments than parameters if
5989 there was a specialization of a member template, like
5990 this:
5992 template <class T> struct S { template <class U> void f(); }
5993 template <> template <class U> void S<int>::f(U);
5995 Here, we'll be substituting into the specialization,
5996 because that's where we can find the code we actually
5997 want to generate, but we'll have enough arguments for
5998 the most general template.
6000 We also deal with the peculiar case:
6002 template <class T> struct S {
6003 template <class U> friend void f();
6004 };
6005 template <class U> void f() {}
6006 template S<int>;
6007 template void f<double>();
6009 Here, the ARGS for the instantiation of will be {int,
6010 double}. But, we only need as many ARGS as there are
6011 levels of template parameters in CODE_PATTERN. We are
6012 careful not to get fooled into reducing the ARGS in
6013 situations like:
6015 template <class T> struct S { template <class U> void f(U); }
6016 template <class T> template <> void S<T>::f(int) {}
6018 which we can spot because the pattern will be a
6019 specialization in this case. */
6021 parms_depth =
6026 }
6027 else
6028 {
6029 /* This special case arises when we have something like this:
6031 template <class T> struct S {
6032 friend void f<int>(int, double);
6033 };
6035 Here, the DECL_TI_TEMPLATE for the friend declaration
6036 will be an IDENTIFIER_NODE. We are being called from
6037 tsubst_friend_function, and we want only to create a
6038 new decl (R) with appropriate types so that we can call
6039 determine_specialization. */
6041 }
6044 {
6047 else
6051 }
6052 else
6053 {
6056 }
6061 /* We do NOT check for matching decls pushed separately at this
6062 point, as they may not represent instantiations of this
6063 template, and in any case are considered separate under the
6064 discrete model. */
6068 /* Clear out the mangled name and RTL for the instantiation. */
6075 /* Type-conversion operator. Reconstruct the name, in
6076 case it's the name of one of the template's parameters. */
6094 {
6099 }
6101 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6102 this in the special friend case mentioned above where
6103 GEN_TMPL is NULL. */
6105 {
6111 /* We're not supposed to instantiate default arguments
6112 until they are called, for a template. But, for a
6113 declaration like:
6115 template <class T> void f ()
6116 { extern void g(int i = T()); }
6118 we should do the substitution when the template is
6119 instantiated. We handle the member function case in
6120 instantiate_class_template since the default arguments
6121 might refer to other members of the class. */
6126 }
6128 /* Copy the list of befriending classes. */
6132 {
6136 in_decl);
6137 }
6140 {
6144 /* If this is an instantiation of a member template, clone it.
6145 If it isn't, that'll be handled by
6146 clone_constructors_and_destructors. */
6149 }
6153 }
6157 {
6166 {
6169 else
6172 }
6181 }
6185 {
6190 /* We don't have to set DECL_CONTEXT here; it is set by
6191 finish_member_declaration. */
6197 }
6201 {
6203 /* It is not a dependent using decl any more. */
6210 }
6216 {
6217 /* If this is the canonical decl, we don't have to mess with
6218 instantiations, and often we can't (for typename, template
6219 type parms and such). Note that TYPE_NAME is not correct for
6220 the above test if we've copied the type for a typedef. */
6223 }
6225 /* Fall through. */
6228 {
6231 tree spec;
6233 tree ctx;
6236 /* Assume this is a non-local variable. */
6241 complain,
6245 else
6246 {
6247 /* Subsequent calls to pushdecl will fill this in. */
6250 }
6252 /* Check to see if we already have this specialization. */
6254 {
6259 }
6260 else
6264 {
6267 }
6271 {
6275 }
6281 /* Clear out the mangled name and RTL for the instantiation. */
6285 /* Don't try to expand the initializer until someone tries to use
6286 this variable; otherwise we run into circular dependencies. */
6291 /* Even if the original location is out of scope, the newly
6292 substituted one is not. */
6294 {
6297 }
6300 {
6301 /* A static data member declaration is always marked
6302 external when it is declared in-class, even if an
6303 initializer is present. We mimic the non-template
6304 processing here. */
6310 }
6311 else
6317 /* Compute the size, alignment, etc. of R. */
6319 }
6324 }
6326 /* Restore the file and line information. */
6330 }
6332 /* Substitute into the ARG_TYPES of a function type. */
6334 static tree
6336 tree args,
6337 tsubst_flags_t complain,
6338 tree in_decl)
6339 {
6340 tree remaining_arg_types;
6341 tree type;
6355 {
6357 {
6361 }
6363 }
6365 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6366 top-level qualifiers as required. */
6369 /* Note that we do not substitute into default arguments here. The
6370 standard mandates that they be instantiated only when needed,
6371 which is done in build_over_call. */
6373 remaining_arg_types);
6375 }
6377 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6378 *not* handle the exception-specification for FNTYPE, because the
6379 initial substitution of explicitly provided template parameters
6380 during argument deduction forbids substitution into the
6381 exception-specification:
6383 [temp.deduct]
6385 All references in the function type of the function template to the
6386 corresponding template parameters are replaced by the specified tem-
6387 plate argument values. If a substitution in a template parameter or
6388 in the function type of the function template results in an invalid
6389 type, type deduction fails. [Note: The equivalent substitution in
6390 exception specifications is done only when the function is instanti-
6391 ated, at which point a program is ill-formed if the substitution
6392 results in an invalid type.] */
6394 static tree
6396 tree args,
6397 tsubst_flags_t complain,
6398 tree in_decl)
6399 {
6400 tree return_type;
6401 tree arg_types;
6402 tree fntype;
6404 /* The TYPE_CONTEXT is not used for function/method types. */
6407 /* Substitute the return type. */
6412 /* Substitute the argument types. */
6418 /* Construct a new type node and return it. */
6421 else
6422 {
6425 {
6426 /* [temp.deduct]
6428 Type deduction may fail for any of the following
6429 reasons:
6431 -- Attempting to create "pointer to member of T" when T
6432 is not a class type. */
6435 r);
6437 }
6441 }
6446 }
6448 /* Substitute into the PARMS of a call-declarator. */
6450 static tree
6452 tree args,
6453 tsubst_flags_t complain,
6454 tree in_decl)
6455 {
6456 tree new_parms;
6457 tree type;
6458 tree defarg;
6466 /* Figure out the type of this parameter. */
6469 /* Figure out the default argument as well. Note that we use
6470 tsubst_expr since the default argument is really an expression. */
6473 /* Chain this parameter on to the front of those we have already
6474 processed. We don't use hash_tree_cons because that function
6475 doesn't check TREE_PARMLIST. */
6478 /* And note that these are parameters. */
6482 }
6484 /* Take the tree structure T and replace template parameters used
6485 therein with the argument vector ARGS. IN_DECL is an associated
6486 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6487 Issue error and warning messages under control of COMPLAIN. Note
6488 that we must be relatively non-tolerant of extensions here, in
6489 order to preserve conformance; if we allow substitutions that
6490 should not be allowed, we may allow argument deductions that should
6491 not succeed, and therefore report ambiguous overload situations
6492 where there are none. In theory, we could allow the substitution,
6493 but indicate that it should have failed, and allow our caller to
6494 make sure that the right thing happens, but we don't try to do this
6495 yet.
6497 This function is used for dealing with types, decls and the like;
6498 for expressions, use tsubst_expr or tsubst_copy. */
6500 static tree
6502 {
6514 else
6533 {
6560 {
6563 /* The array dimension behaves like a non-type template arg,
6564 in that we want to fold it as much as possible. */
6570 {
6571 /* Still allow an explicit array of size zero. */
6574 }
6578 {
6579 /* [temp.deduct]
6581 Type deduction may fail for any of the following
6582 reasons:
6584 Attempting to create an array with a size that is
6585 zero or negative. */
6590 }
6593 }
6599 {
6609 {
6612 }
6613 else
6614 {
6617 }
6620 {
6630 {
6632 {
6634 return cp_build_qualified_type_real
6637 }
6639 {
6640 /* We are processing a type constructed from
6641 a template template parameter. */
6647 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6648 we are resolving nested-types in the signature of
6649 a member function templates.
6650 Otherwise ARG is a TEMPLATE_DECL and is the real
6651 template to be instantiated. */
6659 complain);
6660 return cp_build_qualified_type_real
6662 }
6663 else
6664 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6666 }
6667 }
6668 else
6672 /* This can happen during the attempted tsubst'ing in
6673 unify. This means that we don't yet have any information
6674 about the template parameter in question. */
6677 /* If we get here, we must have been looking at a parm for a
6678 more deeply nested template. Make a new version of this
6679 template parameter, but with a lower level. */
6681 {
6686 {
6688 r = cp_build_qualified_type_real
6692 }
6693 else
6694 {
6705 {
6713 }
6714 }
6723 }
6726 }
6729 {
6737 {
6741 }
6744 {
6748 }
6751 {
6755 }
6761 {
6764 }
6765 else
6768 }
6771 {
6772 /* A binfo node. We always need to make a copy, of the node
6773 itself and of its BINFO_BASETYPES. */
6777 /* Make sure type isn't a typedef copy. */
6782 {
6787 }
6789 }
6791 /* Otherwise, a vector of template arguments. */
6796 {
6805 /* [temp.deduct]
6807 Type deduction may fail for any of the following
6808 reasons:
6810 -- Attempting to create a pointer to reference type.
6811 -- Attempting to create a reference to a reference type or
6812 a reference to void. */
6815 {
6818 /* We keep track of the last time we issued this error
6819 message to avoid spewing a ton of messages during a
6820 single bad template instantiation. */
6824 {
6827 else
6830 type);
6832 }
6835 }
6837 {
6841 }
6842 else
6847 /* Will this ever be needed for TYPE_..._TO values? */
6851 }
6853 {
6856 {
6857 /* [temp.deduct]
6859 Type deduction may fail for any of the following
6860 reasons:
6862 -- Attempting to create "pointer to member of T" when T
6863 is not a class type. */
6867 }
6869 {
6874 }
6877 {
6878 /* This is really a method type. The cv qualifiers of the
6879 this pointer should _not_ be determined by the cv
6880 qualifiers of the class type. They should be held
6881 somewhere in the FUNCTION_TYPE, but we don't do that at
6882 the moment. Consider
6883 typedef void (Func) () const;
6885 template <typename T1> void Foo (Func T1::*);
6887 */
6888 tree method_type;
6894 }
6895 else
6898 complain);
6899 }
6902 {
6903 tree fntype;
6904 tree raises;
6910 /* Substitute the exception specification. */
6913 {
6918 else
6920 {
6927 }
6929 }
6931 }
6933 {
6938 /* As an optimization, we avoid regenerating the array type if
6939 it will obviously be the same as T. */
6943 /* These checks should match the ones in grokdeclarator.
6945 [temp.deduct]
6947 The deduction may fail for any of the following reasons:
6949 -- Attempting to create an array with an element type that
6950 is void, a function type, or a reference type, or [DR337]
6951 an abstract class type. */
6955 {
6959 }
6961 {
6964 type);
6966 }
6970 }
6974 {
6982 }
6986 {
6992 }
6995 {
7005 {
7008 ctx);
7010 }
7012 {
7013 /* Normally, make_typename_type does not require that the CTX
7014 have complete type in order to allow things like:
7016 template <class T> struct S { typename S<T>::X Y; };
7018 But, such constructs have already been resolved by this
7019 point, so here CTX really should have complete type, unless
7020 it's a partial instantiation. */
7023 {
7027 }
7028 }
7035 {
7038 }
7040 return cp_build_qualified_type_real
7042 }
7045 {
7054 }
7057 {
7062 }
7065 {
7070 }
7073 {
7080 }
7083 {
7085 tree e2 = (tsubst_call_declarator_parms
7095 }
7098 {
7105 }
7108 {
7116 complain);
7117 }
7123 }
7124 }
7126 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7127 type of the expression on the left-hand side of the "." or "->"
7128 operator. */
7130 static tree
7133 {
7134 tree name;
7135 tree qualifying_scope;
7136 tree fns;
7140 /* A baselink indicates a function from a base class. The
7141 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7142 non-dependent types; otherwise, the lookup could not have
7143 succeeded. However, they may indicate bases of the template
7144 class, rather than the instantiated class.
7146 In addition, lookups that were not ambiguous before may be
7147 ambiguous now. Therefore, we perform the lookup again. */
7151 {
7158 }
7165 template_args);
7169 qualifying_scope,
7170 object_type);
7171 }
7173 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7174 true if the qualified-id will be a postfix-expression in-and-of
7175 itself; false if more of the postfix-expression follows the
7176 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7177 of "&". */
7179 static tree
7183 {
7184 tree expr;
7185 tree scope;
7186 tree name;
7188 tree template_args;
7192 /* Figure out what name to look up. */
7195 {
7202 }
7203 else
7204 {
7207 }
7209 /* Substitute into the qualifying scope. When there are no ARGS, we
7210 are just trying to simplify a non-dependent expression. In that
7211 case the qualifying scope may be dependent, and, in any case,
7212 substituting will not help. */
7215 {
7218 }
7219 else
7225 {
7229 {
7232 qualified_id);
7234 }
7235 }
7239 scope);
7241 /* Remember that there was a reference to this entity. */
7243 {
7247 }
7255 {
7256 expr = (adjust_result_of_qualified_name_lookup
7259 }
7262 }
7264 /* Like tsubst, but deals with expressions. This function just replaces
7265 template parms; to finish processing the resultant expression, use
7266 tsubst_expr. */
7268 static tree
7270 {
7272 tree r;
7280 {
7287 {
7288 tree enum_type;
7289 tree v;
7293 /* There is no need to substitute into namespace-scope
7294 enumerators. */
7298 /* Unfortunately, we cannot just call lookup_name here.
7299 Consider:
7301 template <int I> int f() {
7302 enum E { a = I };
7303 struct S { void g() { E e = a; } };
7304 };
7306 When we instantiate f<7>::S::g(), say, lookup_name is not
7307 clever enough to find f<7>::a. */
7308 enum_type
7318 /* We didn't find the name. That should never happen; if
7319 name-lookup found it during preliminary parsing, we
7320 should find it again here during instantiation. */
7322 }
7327 {
7328 tree ctx;
7334 }
7356 {
7357 /* Template template argument like the following example need
7358 special treatment:
7360 template <template <class> class TT> struct C {};
7361 template <class T> struct D {
7362 template <class U> struct E {};
7363 C<E> c; // #1
7364 };
7365 D<int> d; // #2
7367 We are processing the template argument `E' in #1 for
7368 the template instantiation #2. Originally, `E' is a
7369 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7370 have to substitute this with one having context `D<int>'. */
7374 }
7375 else
7376 /* Ordinary template template argument. */
7385 return build1
7402 return build1
7407 {
7408 tree object;
7409 tree name;
7414 {
7418 }
7421 {
7429 }
7434 in_decl);
7435 else
7438 }
7478 return build_nt
7487 in_decl),
7488 NULL_TREE);
7491 /* This processing should really occur in tsubst_expr. However,
7492 tsubst_expr does not recurse into expressions, since it
7493 assumes that there aren't any statements inside them. So, we
7494 need to expand the STMT_EXPR here. */
7496 {
7502 }
7509 {
7510 r = build_nt
7515 }
7518 {
7519 r = build_nt
7525 }
7528 {
7529 r = build_nt
7535 }
7538 {
7539 /* Substituted template arguments */
7548 }
7551 {
7571 }
7595 {
7598 }
7599 else
7603 {
7604 r = build_constructor
7609 }
7613 in_decl),
7618 }
7619 }
7621 /* Like tsubst_copy for expressions, etc. but also does semantic
7622 processing. */
7624 static tree
7626 {
7628 tsubst_flags_t stmt_expr
7643 {
7657 {
7658 tree r;
7665 else
7668 }
7677 {
7678 tree decl;
7679 tree init;
7686 {
7689 tree decl;
7697 else
7699 }
7700 else
7701 {
7705 {
7708 /* By marking the declaration as instantiated, we avoid
7709 trying to instantiate it. Since instantiate_decl can't
7710 handle local variables, and since we've already done
7711 all that needs to be done, that's the right thing to
7712 do. */
7717 /* Anonymous aggregates are a special case. */
7719 else
7720 {
7724 {
7725 /* For __PRETTY_FUNCTION__ we have to adjust the
7726 initializer. */
7730 }
7731 else
7734 }
7735 }
7736 }
7738 /* A DECL_STMT can also be used as an expression, in the condition
7739 clause of an if/for/while construct. If we aren't followed by
7740 another statement, return our decl. */
7743 }
7747 {
7755 stmt);
7760 }
7764 {
7769 stmt);
7772 }
7776 {
7783 stmt);
7784 }
7788 {
7793 stmt);
7796 {
7799 }
7802 {
7806 }
7809 }
7813 {
7817 else
7822 in_decl);
7826 else
7828 }
7842 {
7843 tree val;
7851 }
7858 in_decl));
7875 /* Computed goto's must be tsubst'd into. On the other hand,
7876 non-computed gotos must not be; the identifier in question
7877 will have no binding. */
7879 else
7886 tmp = finish_asm_stmt
7898 {
7904 stmt);
7905 }
7906 else
7907 {
7910 else
7917 else
7923 else
7925 }
7929 {
7930 tree decl;
7935 {
7938 /* Prevent instantiate_decl from trying to instantiate
7939 this variable. We've already done all that needs to be
7940 done. */
7942 }
7943 else
7948 }
7958 }
7961 }
7963 /* T is a postfix-expression that is not being used in a function
7964 call. Return the substituted version of T. */
7966 static tree
7968 tsubst_flags_t complain,
7969 tree in_decl)
7970 {
7974 else
7979 }
7981 /* Like tsubst but deals with expressions and performs semantic
7982 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
7984 tree
7986 tree args,
7987 tsubst_flags_t complain,
7988 tree in_decl,
7990 {
7991 #define RECUR(NODE) \
7994 tree op1;
8000 {
8003 /* Fallthrough. */
8005 {
8006 tree decl;
8007 cp_id_kind idk;
8008 tree qualifying_class;
8013 {
8016 }
8018 /* Look up the name. */
8021 /* By convention, expressions use ERROR_MARK_NODE to indicate
8022 failure, not NULL_TREE. */
8038 }
8041 {
8042 tree object;
8050 {
8053 }
8054 else
8061 else
8063 }
8069 return build_functional_cast
8074 return build_reinterpret_cast
8079 return build_const_cast
8084 return build_dynamic_cast
8089 return build_static_cast
8115 else
8117 in_decl);
8153 return build_x_binary_op
8165 /* new-type-id */
8170 /* Remember that there was a reference to this entity. */
8179 {
8180 /* When there are no ARGS, we are trying to evaluate a
8181 non-dependent expression from the parser. Trying to do
8182 the substitutions may not work. */
8185 }
8186 else
8187 {
8191 }
8194 else
8198 return build_x_modify_expr
8206 /* Remember that there was a reference to this entity. */
8212 return build_new
8219 return delete_sanity
8230 {
8231 tree function;
8232 tree call_args;
8237 /* When we parsed the expression, we determined whether or
8238 not Koenig lookup should be performed. */
8241 {
8246 }
8247 else
8248 {
8253 in_decl,
8257 }
8268 {
8271 }
8273 /* Remember that there was a reference to this entity. */
8289 koenig_p);
8290 }
8293 return build_x_conditional_expr
8299 return finish_pseudo_destructor_expr
8305 {
8325 }
8328 {
8329 tree object;
8330 tree member;
8334 /* Remember that there was a reference to this entity. */
8343 else
8347 {
8350 NULL_TREE,
8355 object,
8357 }
8360 {
8361 tree tmpl;
8362 tree args;
8364 /* Lookup the template functions now that we know what the
8365 scope is. */
8374 args);
8375 else
8376 {
8379 }
8380 }
8385 }
8388 return build_throw
8392 {
8393 tree r;
8394 tree elts;
8398 /* digest_init will do the wrong thing if we let it. */
8403 /* We do not want to process the purpose of aggregate
8404 initializers as they are identifier nodes which will be
8405 looked up by digest_init. */
8408 elts;
8410 {
8418 }
8426 }
8429 {
8434 }
8442 else
8443 /* If there are no ARGS, then we are evaluating a
8444 non-dependent expression. If the expression is
8445 non-dependent, the variable must be a constant. */
8452 in_decl));
8456 }
8458 #undef RECUR
8459 }
8461 /* Verify that the instantiated ARGS are valid. For type arguments,
8462 make sure that the type's linkage is ok. For non-type arguments,
8463 make sure they are constants if they are integral or enumerations.
8464 Emit an error under control of COMPLAIN, and return TRUE on error. */
8466 static bool
8468 {
8473 {
8477 {
8478 /* [basic.link]: A name with no linkage (notably, the name
8479 of a class or enumeration declared in a local scope)
8480 shall not be used to declare an entity with linkage.
8481 This implies that names with no linkage cannot be used as
8482 template arguments. */
8486 {
8491 else
8494 }
8495 /* In order to avoid all sorts of complications, we do not
8496 allow variably-modified types as template arguments. */
8498 {
8502 }
8503 }
8504 /* A non-type argument of integral or enumerated type must be a
8505 constant. */
8509 {
8513 }
8514 }
8518 }
8520 /* Instantiate the indicated variable or function template TMPL with
8521 the template arguments in TARG_PTR. */
8523 tree
8525 {
8526 tree fndecl;
8527 tree gen_tmpl;
8528 tree spec;
8535 /* If this function is a clone, handle it specially. */
8537 {
8539 complain);
8540 tree clone;
8542 /* Look for the clone. */
8548 /* We should always have found the clone by now. */
8551 }
8553 /* Check to see if we already have this specialization. */
8560 {
8561 /* The TMPL is a partial instantiation. To get a full set of
8562 arguments we must add the arguments used to perform the
8563 partial instantiation. */
8565 targ_ptr);
8567 /* Check to see if we already have this specialization. */
8571 }
8574 complain))
8577 /* We are building a FUNCTION_DECL, during which the access of its
8578 parameters and return types have to be checked. However this
8579 FUNCTION_DECL which is the desired context for access checking
8580 is not built yet. We solve this chicken-and-egg problem by
8581 deferring all checks until we have the FUNCTION_DECL. */
8584 /* Substitute template parameters. */
8588 /* Now we know the specialization, compute access previously
8589 deferred. */
8595 /* The DECL_TI_TEMPLATE should always be the immediate parent
8596 template, not the most general template. */
8599 /* If we've just instantiated the main entry point for a function,
8600 instantiate all the alternate entry points as well. We do this
8601 by cloning the instantiation of the main entry point, not by
8602 instantiating the template clones. */
8607 }
8609 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8610 arguments that are being used when calling it. TARGS is a vector
8611 into which the deduced template arguments are placed.
8613 Return zero for success, 2 for an incomplete match that doesn't resolve
8614 all the types, and 1 for complete failure. An error message will be
8615 printed only for an incomplete match.
8617 If FN is a conversion operator, or we are trying to produce a specific
8618 specialization, RETURN_TYPE is the return type desired.
8620 The EXPLICIT_TARGS are explicit template arguments provided via a
8621 template-id.
8623 The parameter STRICT is one of:
8625 DEDUCE_CALL:
8626 We are deducing arguments for a function call, as in
8627 [temp.deduct.call].
8629 DEDUCE_CONV:
8630 We are deducing arguments for a conversion function, as in
8631 [temp.deduct.conv].
8633 DEDUCE_EXACT:
8634 We are deducing arguments when doing an explicit instantiation
8635 as in [temp.explicit], when determining an explicit specialization
8636 as in [temp.expl.spec], or when taking the address of a function
8637 template, as in [temp.deduct.funcaddr].
8639 DEDUCE_ORDER:
8640 We are deducing arguments when calculating the partial
8641 ordering between specializations of function or class
8642 templates, as in [temp.func.order] and [temp.class.order].
8644 LEN is the number of parms to consider before returning success, or -1
8645 for all. This is used in partial ordering to avoid comparing parms for
8646 which no actual argument was passed, since they are not considered in
8647 overload resolution (and are explicitly excluded from consideration in
8648 partial ordering in [temp.func.order]/6). */
8650 int
8652 tree explicit_targs,
8653 tree targs,
8654 tree args,
8655 tree return_type,
8656 unification_kind_t strict,
8658 {
8659 tree parms;
8660 tree fntype;
8667 {
8668 /* [temp.deduct]
8670 The specified template arguments must match the template
8671 parameters in kind (i.e., type, nontype, template), and there
8672 must not be more arguments than there are parameters;
8673 otherwise type deduction fails.
8675 Nontype arguments must match the types of the corresponding
8676 nontype template parameters, or must be convertible to the
8677 types of the corresponding nontype parameters as specified in
8678 _temp.arg.nontype_, otherwise type deduction fails.
8680 All references in the function type of the function template
8681 to the corresponding template parameters are replaced by the
8682 specified template argument values. If a substitution in a
8683 template parameter or in the function type of the function
8684 template results in an invalid type, type deduction fails. */
8686 tree converted_args;
8689 converted_args
8696 /* Substitute the explicit args into the function type. This is
8697 necessary so that, for instance, explicitly declared function
8698 arguments can match null pointed constants. If we were given
8699 an incomplete set of explicit args, we must not do semantic
8700 processing during substitution as we could create partial
8701 instantiations. */
8710 /* Place the explicitly specified arguments in TARGS. */
8713 }
8716 /* Never do unification on the 'this' parameter. */
8721 {
8722 /* We've been given a return type to match, prepend it. */
8727 }
8729 /* We allow incomplete unification without an error message here
8730 because the standard doesn't seem to explicitly prohibit it. Our
8731 callers must be ready to deal with unification failures in any
8732 event. */
8738 /* All is well so far. Now, check:
8740 [temp.deduct]
8742 When all template arguments have been deduced, all uses of
8743 template parameters in nondeduced contexts are replaced with
8744 the corresponding deduced argument values. If the
8745 substitution results in an invalid type, as described above,
8746 type deduction fails. */
8752 }
8754 /* Adjust types before performing type deduction, as described in
8755 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8756 sections are symmetric. PARM is the type of a function parameter
8757 or the return type of the conversion function. ARG is the type of
8758 the argument passed to the call, or the type of the value
8759 initialized with the result of the conversion function. */
8761 static int
8765 {
8769 {
8774 {
8775 /* Swap PARM and ARG throughout the remainder of this
8776 function; the handling is precisely symmetric since PARM
8777 will initialize ARG rather than vice versa. */
8782 }
8785 /* There is nothing to do in this case. */
8789 /* DR 214. [temp.func.order] is underspecified, and leads to no
8790 ordering between things like `T *' and `T const &' for `U *'.
8791 The former has T=U and the latter T=U*. The former looks more
8792 specialized and John Spicer considers it well-formed (the EDG
8793 compiler accepts it).
8795 John also confirms that deduction should proceed as in a function
8796 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8797 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8798 to an actual call can have such a type.
8800 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8801 If only ARG is a REFERENCE_TYPE, we look through that and then
8802 proceed as with DEDUCE_CALL (which could further convert it). */
8804 {
8808 }
8812 }
8815 {
8816 /* [temp.deduct.call]
8818 If P is not a reference type:
8820 --If A is an array type, the pointer type produced by the
8821 array-to-pointer standard conversion (_conv.array_) is
8822 used in place of A for type deduction; otherwise,
8824 --If A is a function type, the pointer type produced by
8825 the function-to-pointer standard conversion
8826 (_conv.func_) is used in place of A for type deduction;
8827 otherwise,
8829 --If A is a cv-qualified type, the top level
8830 cv-qualifiers of A's type are ignored for type
8831 deduction. */
8836 else
8838 }
8840 /* [temp.deduct.call]
8842 If P is a cv-qualified type, the top level cv-qualifiers
8843 of P's type are ignored for type deduction. If P is a
8844 reference type, the type referred to by P is used for
8845 type deduction. */
8848 {
8851 }
8853 /* DR 322. For conversion deduction, remove a reference type on parm
8854 too (which has been swapped into ARG). */
8859 }
8861 /* Most parms like fn_type_unification.
8863 If SUBR is 1, we're being called recursively (to unify the
8864 arguments of a function or method parameter of a function
8865 template). */
8867 static int
8869 tree targs,
8870 tree xparms,
8871 tree xargs,
8873 unification_kind_t strict,
8876 {
8892 {
8912 }
8917 again:
8924 && args
8926 {
8935 /* We can't deduce anything from this, but we might get all the
8936 template args from other function args. */
8939 /* Conversions will be performed on a function argument that
8940 corresponds with a function parameter that contains only
8941 non-deducible template parameters and explicitly specified
8942 template parameters. */
8944 {
8945 tree type;
8949 else
8950 {
8953 }
8956 {
8959 }
8960 else
8961 /* It might work; we shouldn't check now, because we might
8962 get into infinite recursion. Overload resolution will
8963 handle it. */
8967 }
8970 {
8973 {
8974 /* [temp.deduct.type] A template-argument can be deduced from
8975 a pointer to function or pointer to member function
8976 argument if the set of overloaded functions does not
8977 contain function templates and at most one of a set of
8978 overloaded functions provides a unique match. */
8985 }
8989 }
8991 {
8999 }
9001 /* Are we done with the interesting parms? */
9004 }
9005 /* Fail if we've reached the end of the parm list, and more args
9006 are present, and the parm list isn't variadic. */
9009 /* Fail if parms are left and they don't have default values. */
9015 done:
9019 {
9022 /* If this is an undeduced nontype parameter that depends on
9023 a type parameter, try another pass; its type may have been
9024 deduced from a later argument than the one from which
9025 this parameter can be deduced. */
9034 }
9036 }
9038 /* Subroutine of type_unification_real. Args are like the variables at the
9039 call site. ARG is an overloaded function (or template-id); we try
9040 deducing template args from each of the overloads, and if only one
9041 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9043 static int
9045 tree targs,
9046 tree parm,
9047 tree arg,
9048 unification_kind_t strict,
9050 {
9056 {
9059 }
9060 else
9064 /* Handle `&x' where `x' is some static or non-static member
9065 function name. */
9071 /* Strip baselink information. */
9076 {
9077 /* If we got some explicit template args, we need to plug them into
9078 the affected templates before we try to unify, in case the
9079 explicit args will completely resolve the templates in question. */
9085 {
9093 expl_subargs);
9095 {
9099 }
9100 }
9101 }
9104 {
9109 }
9110 else
9113 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9114 to function or pointer to member function argument if the set of
9115 overloaded functions does not contain function templates and at most
9116 one of a set of overloaded functions provides a unique match.
9118 So if we found multiple possibilities, we return success but don't
9119 deduce anything. */
9122 {
9127 }
9132 }
9134 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9135 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9136 different overloads deduce different arguments for a given parm.
9137 ADDR_P is true if the expression for which deduction is being
9138 performed was of the form "& fn" rather than simply "fn".
9140 Returns 1 on success. */
9142 static int
9144 tree orig_targs,
9145 tree targs,
9146 tree parm,
9147 tree arg,
9148 unification_kind_t strict,
9151 {
9153 tree tempargs;
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 this is a template, just return success. */
9173 /* We don't copy orig_targs for this because if we have already deduced
9174 some template args from previous args, unify would complain when we
9175 try to deduce a template parameter for the same argument, even though
9176 there isn't really a conflict. */
9183 /* First make sure we didn't deduce anything that conflicts with
9184 explicitly specified args. */
9186 {
9193 {
9194 /* Since we're unifying against ourselves, we will fill in template
9195 args used in the function parm list with our own template parms.
9196 Discard them. */
9199 }
9202 }
9205 {
9210 }
9213 }
9215 /* Verify that nondeduce template argument agrees with the type
9216 obtained from argument deduction. Return nonzero if the
9217 verification fails.
9219 For example:
9221 struct A { typedef int X; };
9222 template <class T, class U> struct C {};
9223 template <class T> struct C<T, typename T::X> {};
9225 Then with the instantiation `C<A, int>', we can deduce that
9226 `T' is `A' but unify () does not check whether `typename T::X'
9227 is `int'. This function ensure that they agree.
9229 TARGS, PARMS are the same as the arguments of unify.
9230 ARGS contains template arguments from all levels. */
9232 static int
9234 {
9241 }
9243 /* PARM is a template class (perhaps with unbound template
9244 parameters). ARG is a fully instantiated type. If ARG can be
9245 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9246 TARGS are as for unify. */
9248 static tree
9250 {
9251 tree copy_of_targs;
9258 /* We need to make a new template argument vector for the call to
9259 unify. If we used TARGS, we'd clutter it up with the result of
9260 the attempted unification, even if this class didn't work out.
9261 We also don't want to commit ourselves to all the unifications
9262 we've already done, since unification is supposed to be done on
9263 an argument-by-argument basis. In other words, consider the
9264 following pathological case:
9266 template <int I, int J, int K>
9267 struct S {};
9269 template <int I, int J>
9270 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9272 template <int I, int J, int K>
9273 void f(S<I, J, K>, S<I, I, I>);
9275 void g() {
9276 S<0, 0, 0> s0;
9277 S<0, 1, 2> s2;
9279 f(s0, s2);
9280 }
9282 Now, by the time we consider the unification involving `s2', we
9283 already know that we must have `f<0, 0, 0>'. But, even though
9284 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9285 because there are two ways to unify base classes of S<0, 1, 2>
9286 with S<I, I, I>. If we kept the already deduced knowledge, we
9287 would reject the possibility I=1. */
9290 /* If unification failed, we're done. */
9296 }
9298 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9299 have already discovered to be satisfactory. ARG_BINFO is the binfo
9300 for the base class of ARG that we are currently examining. */
9302 static tree
9304 tree targs,
9305 tree parm,
9306 tree arg_binfo,
9307 tree rval,
9309 {
9310 tree binfos;
9315 {
9319 /* If there is more than one satisfactory baseclass, then:
9321 [temp.deduct.call]
9323 If they yield more than one possible deduced A, the type
9324 deduction fails.
9326 applies. */
9331 }
9336 /* Process base types. */
9338 {
9342 /* Skip this base, if we've already seen it. */
9346 this_virtual =
9349 /* When searching for a non-virtual, we cannot mark virtually
9350 found binfos. */
9355 parm,
9356 base_binfo,
9357 rval,
9360 /* If we discovered more than one matching base class, we can
9361 stop now. */
9364 }
9367 }
9369 /* Given a template type PARM and a class type ARG, find the unique
9370 base type in ARG that is an instance of PARM. We do not examine
9371 ARG itself; only its base-classes. If there is no appropriate base
9372 class, return NULL_TREE. If there is more than one, return
9373 error_mark_node. PARM may be the type of a partial specialization,
9374 as well as a plain template type. Used by unify. */
9376 static tree
9378 {
9379 tree rval;
9380 tree arg_binfo;
9387 NULL_TREE,
9388 GTB_IGNORE_TYPE);
9390 /* Since get_template_base_recursive marks the bases classes, we
9391 must unmark them here. */
9395 }
9397 /* Returns the level of DECL, which declares a template parameter. */
9399 static int
9401 {
9403 {
9414 }
9415 }
9417 /* Decide whether ARG can be unified with PARM, considering only the
9418 cv-qualifiers of each type, given STRICT as documented for unify.
9419 Returns nonzero iff the unification is OK on that basis.*/
9421 static int
9423 {
9428 {
9429 /* If the cvr quals of parm will not unify with ARG, they'll be
9430 ignored in instantiation, so we have to do the same here. */
9436 }
9447 }
9449 /* Takes parameters as for type_unification. Returns 0 if the
9450 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9451 bitwise or of the following flags:
9453 UNIFY_ALLOW_NONE:
9454 Require an exact match between PARM and ARG.
9455 UNIFY_ALLOW_MORE_CV_QUAL:
9456 Allow the deduced ARG to be more cv-qualified (by qualification
9457 conversion) than ARG.
9458 UNIFY_ALLOW_LESS_CV_QUAL:
9459 Allow the deduced ARG to be less cv-qualified than ARG.
9460 UNIFY_ALLOW_DERIVED:
9461 Allow the deduced ARG to be a template base class of ARG,
9462 or a pointer to a template base class of the type pointed to by
9463 ARG.
9464 UNIFY_ALLOW_INTEGER:
9465 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9466 case for more information.
9467 UNIFY_ALLOW_OUTER_LEVEL:
9468 This is the outermost level of a deduction. Used to determine validity
9469 of qualification conversions. A valid qualification conversion must
9470 have const qualified pointers leading up to the inner type which
9471 requires additional CV quals, except at the outer level, where const
9472 is not required [conv.qual]. It would be normal to set this flag in
9473 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9474 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9475 This is the outermost level of a deduction, and PARM can be more CV
9476 qualified at this point.
9477 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9478 This is the outermost level of a deduction, and PARM can be less CV
9479 qualified at this point.
9480 UNIFY_ALLOW_MAX_CORRECTION:
9481 This is an INTEGER_TYPE's maximum value. Used if the range may
9482 have been derived from a size specification, such as an array size.
9483 If the size was given by a nontype template parameter N, the maximum
9484 value will have the form N-1. The flag says that we can (and indeed
9485 must) unify N with (ARG + 1), an exception to the normal rules on
9486 folding PARM. */
9488 static int
9490 {
9492 tree targ;
9493 tree tparm;
9496 /* I don't think this will do the right thing with respect to types.
9497 But the only case I've seen it in so far has been array bounds, where
9498 signedness is the only information lost, and I think that will be
9499 okay. */
9506 /* We can't deduce anything from this, but we might get all the
9507 template args from other function args. */
9510 /* If PARM uses template parameters, then we can't bail out here,
9511 even if ARG == PARM, since we won't record unifications for the
9512 template parameters. We might need them if we're trying to
9513 figure out which of two things is more specialized. */
9517 /* Immediately reject some pairs that won't unify because of
9518 cv-qualification mismatches. */
9521 /* It is the elements of the array which hold the cv quals of an array
9522 type, and the elements might be template type parms. We'll check
9523 when we recurse. */
9525 /* We check the cv-qualifiers when unifying with template type
9526 parameters below. We want to allow ARG `const T' to unify with
9527 PARM `T' for example, when computing which of two templates
9528 is more specialized, for example. */
9543 {
9547 /* In a type which contains a nested-name-specifier, template
9548 argument values cannot be deduced for template parameters used
9549 within the nested-name-specifier. */
9559 /* The PARM is not one we're trying to unify. Just check
9560 to see if it matches ARG. */
9567 /* Check for mixed types and values. */
9575 {
9576 /* ARG must be constructed from a template class or a template
9577 template parameter. */
9582 {
9586 tree argtmplvec
9590 /* The parameter and argument roles have to be switched here
9591 in order to handle default arguments properly. For example,
9592 template<template <class> class TT> void f(TT<int>)
9593 should be able to accept vector<int> which comes from
9594 template <class T, class Allocator = allocator>
9595 class vector. */
9601 /* Deduce arguments T, i from TT<T> or TT<i>.
9602 We check each element of PARMVEC and ARGVEC individually
9603 rather than the whole TREE_VEC since they can have
9604 different number of elements. */
9607 {
9612 UNIFY_ALLOW_NONE))
9614 }
9615 }
9618 /* Fall through to deduce template name. */
9619 }
9623 {
9624 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9626 /* Simple cases: Value already set, does match or doesn't. */
9631 }
9632 else
9633 {
9634 /* If PARM is `const T' and ARG is only `int', we don't have
9635 a match unless we are allowing additional qualification.
9636 If ARG is `const int' and PARM is just `T' that's OK;
9637 that binds `const int' to `T'. */
9642 /* Consider the case where ARG is `const volatile int' and
9643 PARM is `const T'. Then, T should be `volatile int'. */
9644 arg = cp_build_qualified_type_real
9649 /* Simple cases: Value already set, does match or doesn't. */
9655 /* Make sure that ARG is not a variable-sized array. (Note
9656 that were talking about variable-sized arrays (like
9657 `int[n]'), rather than arrays of unknown size (like
9658 `int[]').) We'll get very confused by such a type since
9659 the bound of the array will not be computable in an
9660 instantiation. Besides, such types are not allowed in
9661 ISO C++, so we can do as we please here. */
9664 }
9674 /* The PARM is not one we're trying to unify. Just check
9675 to see if it matches ARG. */
9685 /* [temp.deduct.type] If, in the declaration of a function template
9686 with a non-type template-parameter, the non-type
9687 template-parameter is used in an expression in the function
9688 parameter-list and, if the corresponding template-argument is
9689 deduced, the template-argument type shall match the type of the
9690 template-parameter exactly, except that a template-argument
9691 deduced from an array bound may be of any integral type.
9692 The non-type parameter might use already deduced type parameters. */
9695 /* Template-parameter dependent expression. Just accept it for now.
9696 It will later be processed in convert_template_argument. */
9697 ;
9705 /* We haven't deduced the type of this parameter yet. Try again
9706 later. */
9708 else
9715 {
9716 /* A pointer-to-member constant can be unified only with
9717 another constant. */
9721 /* Just unify the class member. It would be useless (and possibly
9722 wrong, depending on the strict flags) to unify also
9723 PTRMEM_CST_CLASS, because we want to be sure that both parm and
9724 arg refer to the same variable, even if through different
9725 classes. For instance:
9727 struct A { int x; };
9728 struct B : A { };
9730 Unification of &A::x and &B::x must succeed. */
9733 }
9736 {
9740 /* [temp.deduct.call]
9742 A can be another pointer or pointer to member type that can
9743 be converted to the deduced A via a qualification
9744 conversion (_conv.qual_).
9746 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9747 This will allow for additional cv-qualification of the
9748 pointed-to types if appropriate. */
9751 /* The derived-to-base conversion only persists through one
9752 level of pointers. */
9757 }
9789 {
9799 }
9800 /* We have already checked cv-qualification at the top of the
9801 function. */
9805 /* As far as unification is concerned, this wins. Later checks
9806 will invalidate it if necessary. */
9809 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9810 /* Type INTEGER_CST can come from ordinary constant template args. */
9820 {
9829 UNIFY_ALLOW_NONE))
9832 }
9840 {
9847 strict);
9848 }
9851 {
9855 {
9856 /* First, we try to unify the PARM and ARG directly. */
9861 {
9862 /* Fallback to the special case allowed in
9863 [temp.deduct.call]:
9865 If P is a class, and P has the form
9866 template-id, then A can be a derived class of
9867 the deduced A. Likewise, if P is a pointer to
9868 a class of the form template-id, A can be a
9869 pointer to a derived class pointed to by the
9870 deduced A. */
9876 }
9877 }
9881 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9882 Then, we should unify `int' and `U'. */
9884 else
9885 /* There's no chance of unification succeeding. */
9890 }
9914 strict);
9925 /* Matched cases are handled by the ARG == PARM test above. */
9931 {
9932 /* We handle this case specially, since it comes up with
9933 arrays. In particular, something like:
9935 template <int N> void f(int (&x)[N]);
9937 Here, we are trying to unify the range type, which
9938 looks like [0 ... (N - 1)]. */
9946 }
9947 /* Else fall through. */
9951 {
9953 /* We're looking at an expression. This can happen with
9954 something like:
9956 template <int I>
9957 void foo(S<I>, S<I + 2>);
9959 This is a "nondeduced context":
9961 [deduct.type]
9963 The nondeduced contexts are:
9965 --A type that is a template-id in which one or more of
9966 the template-arguments is an expression that references
9967 a template-parameter.
9969 In these cases, we assume deduction succeeded, but don't
9970 actually infer any unifications. */
9975 else
9977 }
9978 else
9983 }
9984 }
9985 \f
9986 /* Called if RESULT is explicitly instantiated, or is a member of an
9987 explicitly instantiated class, or if using -frepo and the
9988 instantiation of RESULT has been assigned to this file. */
9990 void
9992 {
9993 /* We used to set this unconditionally; we moved that to
9994 do_decl_instantiation so it wouldn't get set on members of
9995 explicit class template instantiations. But we still need to set
9996 it here for the 'extern template' case in order to suppress
9997 implicit instantiations. */
10001 /* If this entity has already been written out, it's too late to
10002 make any modifications. */
10007 /* The TREE_PUBLIC flag for function declarations will have been
10008 set correctly by tsubst. */
10011 /* This might have been set by an earlier implicit instantiation. */
10015 {
10019 /* Always make artificials weak. */
10022 /* For WIN32 we also want to put explicit instantiations in
10023 linkonce sections. */
10026 }
10030 }
10032 /* Given two function templates PAT1 and PAT2, return:
10034 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10036 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10037 -1 if PAT2 is more specialized than PAT1.
10038 0 if neither is more specialized.
10040 LEN is passed through to fn_type_unification. */
10042 int
10044 {
10045 tree targs;
10048 /* If template argument deduction succeeds, we substitute the
10049 resulting arguments into non-deduced contexts. While doing that,
10050 we must be aware that we may encounter dependent types. */
10064 }
10066 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10068 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10069 -1 if PAT2 is more specialized than PAT1.
10070 0 if neither is more specialized.
10072 FULL_ARGS is the full set of template arguments that triggers this
10073 partial ordering. */
10075 int
10077 {
10078 tree targs;
10092 }
10094 /* Return the template arguments that will produce the function signature
10095 DECL from the function template FN, with the explicit template
10096 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10097 also match. Return NULL_TREE if no satisfactory arguments could be
10098 found. DEDUCE and LEN are passed through to fn_type_unification. */
10100 static tree
10102 tree decl,
10103 tree explicit_args,
10107 {
10110 tree decl_type;
10111 tree decl_arg_types;
10114 /* Substitute the explicit template arguments into the type of DECL.
10115 The call to fn_type_unification will handle substitution into the
10116 FN. */
10119 {
10120 tree tmpl;
10121 tree converted_args;
10125 else
10126 /* We can get here for some invalid specializations. */
10129 converted_args
10139 }
10142 /* Never do unification on the 'this' parameter. */
10147 decl_arg_types,
10156 }
10158 /* For most uses, we want to check the return type. */
10160 static tree
10162 {
10164 }
10166 /* But for resolve_overloaded_unification, we only care about the parameter
10167 types. */
10169 static tree
10171 {
10173 }
10175 /* Return the innermost template arguments that, when applied to a
10176 template specialization whose innermost template parameters are
10177 TPARMS, and whose specialization arguments are PARMS, yield the
10178 ARGS.
10180 For example, suppose we have:
10182 template <class T, class U> struct S {};
10183 template <class T> struct S<T*, int> {};
10185 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10186 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10187 int}. The resulting vector will be {double}, indicating that `T'
10188 is bound to `double'. */
10190 static tree
10192 {
10197 UNIFY_ALLOW_NONE))
10208 }
10210 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10211 Pick the most specialized template, and return the corresponding
10212 instantiation, or if there is no corresponding instantiation, the
10213 template itself. If there is no most specialized template,
10214 error_mark_node is returned. If there are no templates at all,
10215 NULL_TREE is returned. */
10217 tree
10219 {
10228 {
10232 ;
10233 else
10234 {
10236 {
10240 }
10242 }
10243 }
10246 {
10251 }
10254 }
10256 /* Return the most specialized of the list of templates in FNS that can
10257 produce an instantiation matching DECL, given the explicit template
10258 arguments EXPLICIT_ARGS. */
10260 static tree
10262 {
10267 {
10273 }
10276 }
10278 /* If DECL is a specialization of some template, return the most
10279 general such template. Otherwise, returns NULL_TREE.
10281 For example, given:
10283 template <class T> struct S { template <class U> void f(U); };
10285 if TMPL is `template <class U> void S<int>::f(U)' this will return
10286 the full template. This function will not trace past partial
10287 specializations, however. For example, given in addition:
10289 template <class T> struct S<T*> { template <class U> void f(U); };
10291 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10292 `template <class T> template <class U> S<T*>::f(U)'. */
10294 tree
10296 {
10297 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10298 an immediate specialization. */
10300 {
10304 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10305 template friend. */
10310 }
10312 /* Look for more and more general templates. */
10314 {
10315 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10316 (See cp-tree.h for details.) */
10324 /* Stop if we run into an explicitly specialized class template. */
10331 }
10334 }
10336 /* Return the most specialized of the class template specializations
10337 of TMPL which can produce an instantiation matching ARGS, or
10338 error_mark_node if the choice is ambiguous. */
10340 static tree
10342 {
10344 tree t;
10345 tree champ;
10350 {
10351 tree spec_args
10354 {
10357 }
10358 }
10367 {
10370 ;
10371 else
10372 {
10374 {
10378 }
10380 }
10381 }
10384 {
10388 }
10391 }
10393 /* Explicitly instantiate DECL. */
10395 void
10397 {
10402 /* An error occurred, for which grokdeclarator has already issued
10403 an appropriate message. */
10406 {
10409 }
10411 {
10412 /* There is an asymmetry here in the way VAR_DECLs and
10413 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10414 the latter, the DECL we get back will be marked as a
10415 template instantiation, and the appropriate
10416 DECL_TEMPLATE_INFO will be set up. This does not happen for
10417 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10418 should handle VAR_DECLs as it currently handles
10419 FUNCTION_DECLs. */
10422 {
10425 }
10426 }
10428 {
10431 }
10432 else
10435 /* Check for various error cases. Note that if the explicit
10436 instantiation is valid the RESULT will currently be marked as an
10437 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10438 until we get here. */
10441 {
10442 /* DR 259 [temp.spec].
10444 Both an explicit instantiation and a declaration of an explicit
10445 specialization shall not appear in a program unless the explicit
10446 instantiation follows a declaration of the explicit specialization.
10448 For a given set of template parameters, if an explicit
10449 instantiation of a template appears after a declaration of an
10450 explicit specialization for that template, the explicit
10451 instantiation has no effect. */
10453 }
10455 {
10456 /* [temp.spec]
10458 No program shall explicitly instantiate any template more
10459 than once.
10461 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10462 instantiation was `extern' and the second is not, and EXTERN_P for
10463 the opposite case. If -frepo, chances are we already got marked
10464 as an explicit instantiation because of the repo file. */
10468 /* If we've already instantiated the template, just return now. */
10471 }
10473 {
10476 }
10478 {
10481 }
10484 ;
10486 {
10490 }
10491 else
10493 storage);
10500 }
10502 void
10504 {
10510 {
10513 }
10514 }
10516 /* Called from do_type_instantiation through binding_table_foreach to
10517 do recursive instantiation for the type bound in ENTRY. */
10518 static void
10520 {
10526 }
10528 /* Perform an explicit instantiation of template class T. STORAGE, if
10529 non-null, is the RID for extern, inline or static. COMPLAIN is
10530 nonzero if this is called from the parser, zero if called recursively,
10531 since the standard is unclear (as detailed below). */
10533 void
10535 {
10544 {
10547 }
10552 {
10555 t);
10557 }
10560 {
10571 else
10572 {
10574 storage);
10576 }
10577 }
10580 {
10581 /* DR 259 [temp.spec].
10583 Both an explicit instantiation and a declaration of an explicit
10584 specialization shall not appear in a program unless the explicit
10585 instantiation follows a declaration of the explicit specialization.
10587 For a given set of template parameters, if an explicit
10588 instantiation of a template appears after a declaration of an
10589 explicit specialization for that template, the explicit
10590 instantiation has no effect. */
10592 }
10594 {
10595 /* [temp.spec]
10597 No program shall explicitly instantiate any template more
10598 than once.
10600 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10601 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10602 are we already got marked as an explicit instantiation because of the
10603 repo file. All these cases are OK. */
10608 /* If we've already instantiated the template, just return now. */
10611 }
10619 {
10620 tree tmp;
10622 /* In contrast to implicit instantiation, where only the
10623 declarations, and not the definitions, of members are
10624 instantiated, we have here:
10626 [temp.explicit]
10628 The explicit instantiation of a class template specialization
10629 implies the instantiation of all of its members not
10630 previously explicitly specialized in the translation unit
10631 containing the explicit instantiation.
10633 Of course, we can't instantiate member template classes, since
10634 we don't have any arguments for them. Note that the standard
10635 is unclear on whether the instantiation of the members are
10636 *explicit* instantiations or not. We choose to be generous,
10637 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10638 the explicit instantiation of a class where some of the members
10639 have no definition in the current translation unit. */
10645 {
10650 }
10654 {
10659 }
10664 }
10665 }
10667 /* Given a function DECL, which is a specialization of TMPL, modify
10668 DECL to be a re-instantiation of TMPL with the same template
10669 arguments. TMPL should be the template into which tsubst'ing
10670 should occur for DECL, not the most general template.
10672 One reason for doing this is a scenario like this:
10674 template <class T>
10675 void f(const T&, int i);
10677 void g() { f(3, 7); }
10679 template <class T>
10680 void f(const T& t, const int i) { }
10682 Note that when the template is first instantiated, with
10683 instantiate_template, the resulting DECL will have no name for the
10684 first parameter, and the wrong type for the second. So, when we go
10685 to instantiate the DECL, we regenerate it. */
10687 static void
10689 {
10690 /* The most general version of TMPL. */
10691 tree gen_tmpl;
10692 /* The arguments used to instantiate DECL, from the most general
10693 template. */
10694 tree args;
10695 tree code_pattern;
10696 tree new_decl;
10702 /* Unregister the specialization so that when we tsubst we will not
10703 just return DECL. We don't have to unregister DECL from TMPL
10704 because if would only be registered there if it were a partial
10705 instantiation of a specialization, which it isn't: it's a full
10706 instantiation. */
10711 /* If the DECL was not unregistered then something peculiar is
10712 happening: we created a specialization but did not call
10713 register_specialization for it. */
10716 /* Make sure that we can see identifiers, and compute access
10717 correctly. */
10720 /* Do the substitution to get the new declaration. */
10724 {
10725 /* Set up DECL_INITIAL, since tsubst doesn't. */
10730 }
10732 {
10733 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10734 new decl. */
10736 /* And don't complain about a duplicate definition. */
10738 }
10742 /* The immediate parent of the new template is still whatever it was
10743 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10744 general template. We also reset the DECL_ASSEMBLER_NAME since
10745 tsubst always calculates the name as if the function in question
10746 were really a template instance, and sometimes, with friend
10747 functions, this is not so. See tsubst_friend_function for
10748 details. */
10754 /* Call duplicate decls to merge the old and new declarations. */
10757 /* Now, re-register the specialization. */
10759 }
10761 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10762 substituted to get DECL. */
10764 tree
10766 {
10769 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10770 for the instantiation. This is not always the most general
10771 template. Consider, for example:
10773 template <class T>
10774 struct S { template <class U> void f();
10775 template <> void f<int>(); };
10777 and an instantiation of S<double>::f<int>. We want TD to be the
10778 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10780 more general template. */
10782 /* We must also deal with friend templates. Given:
10784 template <class T> struct S {
10785 template <class U> friend void f() {};
10786 };
10788 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10789 so far as the language is concerned, but that's still
10790 where we get the pattern for the instantiation from. On
10791 other hand, if the definition comes outside the class, say:
10793 template <class T> struct S {
10794 template <class U> friend void f();
10795 };
10796 template <class U> friend void f() {}
10798 we don't need to look any further. That's what the check for
10799 DECL_INITIAL is for. */
10803 {
10804 /* The present template, TD, should not be a definition. If it
10805 were a definition, we should be using it! Note that we
10806 cannot restructure the loop to just keep going until we find
10807 a template with a definition, since that might go too far if
10808 a specialization was declared, but not defined. */
10813 /* Fetch the more general template. */
10815 }
10818 }
10820 /* Produce the definition of D, a _DECL generated from a template. If
10821 DEFER_OK is nonzero, then we don't have to actually do the
10822 instantiation now; we just have to do it sometime. */
10824 tree
10826 {
10828 tree gen_args;
10829 tree args;
10830 tree td;
10831 tree code_pattern;
10832 tree spec;
10833 tree gen_tmpl;
10838 /* This function should only be used to instantiate templates for
10839 functions and static member variables. */
10843 /* Variables are never deferred; if instantiation is required, they
10844 are instantiated right away. That allows for better code in the
10845 case that an expression refers to the value of the variable --
10846 if the variable has a constant value the referring expression can
10847 take advantage of that fact. */
10851 /* Don't instantiate cloned functions. Instead, instantiate the
10852 functions they cloned. */
10857 /* D has already been instantiated. It might seem reasonable to
10858 check whether or not D is an explicit instantiation, and, if so,
10859 stop here. But when an explicit instantiation is deferred
10860 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10861 is set, even though we still need to do the instantiation. */
10864 /* If we already have a specialization of this declaration, then
10865 there's no reason to instantiate it. Note that
10866 retrieve_specialization gives us both instantiations and
10867 specializations, so we must explicitly check
10868 DECL_TEMPLATE_SPECIALIZATION. */
10875 /* This needs to happen before any tsubsting. */
10881 /* We may be in the middle of deferred access check. Disable it now. */
10884 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10885 for the instantiation. */
10891 /* In the case of a friend template whose definition is provided
10892 outside the class, we may have too many arguments. Drop the
10893 ones we don't need. The same is true for specializations. */
10894 args = get_innermost_template_args
10896 else
10901 else
10907 {
10908 /* Let the repository code that this template definition is
10909 available.
10911 The repository doesn't need to know about cloned functions
10912 because they never actually show up in the object file. It
10913 does need to know about the clones; those are the symbols
10914 that the linker will be emitting error messages about. */
10917 {
10918 tree t;
10924 }
10925 else
10930 }
10933 {
10934 /* Recheck the substitutions to obtain any warning messages
10935 about ignoring cv qualifiers. */
10939 /* Make sure that we can see identifiers, and compute access
10940 correctly. D is already the target FUNCTION_DECL with the
10941 right context. */
10945 {
10949 /* Don't simply tsubst the function type, as that will give
10950 duplicate warnings about poor parameter qualifications.
10951 The function arguments are the same as the decl_arguments
10952 without the top level cv qualifiers. */
10954 }
10958 }
10962 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10964 /* Reject all external templates except inline functions. */
10970 /* Defer all other templates, unless we have been explicitly
10971 forbidden from doing so. We restore the source position here
10972 because it's used by add_pending_template. */
10974 {
10979 /* [temp.explicit]
10981 The definition of a non-exported function template, a
10982 non-exported member function template, or a non-exported
10983 member function or static data member of a class template
10984 shall be present in every translation unit in which it is
10985 explicitly instantiated. */
10986 pedwarn
10991 }
10997 /* Mark D as instantiated so that recursive calls to
10998 instantiate_decl do not try to instantiate it again. */
11001 /* Regenerate the declaration in case the template has been modified
11002 by a subsequent redeclaration. */
11005 /* We already set the file and line above. Reset them now in case
11006 they changed as a result of calling
11007 regenerate_decl_from_template. */
11011 {
11012 /* Clear out DECL_RTL; whatever was there before may not be right
11013 since we've reset the type of the declaration. */
11021 {
11022 /* The fact that this code is executing indicates that:
11024 (1) D is a template static data member, for which a
11025 definition is available.
11027 (2) An implicit or explicit instantiation has occurred.
11029 (3) We are not going to emit a definition of the static
11030 data member at this time.
11032 This situation is peculiar, but it occurs on platforms
11033 without weak symbols when performing an implicit
11034 instantiation. There, we cannot implicitly instantiate a
11035 defined static data member in more than one translation
11036 unit, so import_export_decl marks the declaration as
11037 external; we must rely on explicit instantiation.
11039 Reset instantiated marker to make sure that later
11040 explicit instantiation will be processed. */
11042 }
11043 else
11044 {
11045 /* This is done in analogous to `start_decl'. It is
11046 required for correct access checking. */
11052 /* Normally, pop_nested_class is called by cp_finish_decl
11053 above. But when instantiate_decl is triggered during
11054 instantiate_class_template processing, its DECL_CONTEXT
11055 is still not completed yet, and pop_nested_class isn't
11056 called. */
11059 }
11060 }
11062 {
11063 htab_t saved_local_specializations;
11064 tree subst_decl;
11065 tree tmpl_parm;
11066 tree spec_parm;
11068 /* Mark D as instantiated so that recursive calls to
11069 instantiate_decl do not try to instantiate it again. */
11072 /* Save away the current list, in case we are instantiating one
11073 template from within the body of another. */
11076 /* Set up the list of local specializations. */
11078 hash_local_specialization,
11079 eq_local_specializations,
11080 NULL);
11082 /* Set up context. */
11086 /* Create substitution entries for the parameters. */
11091 {
11095 }
11097 {
11101 }
11104 /* Substitute into the body of the function. */
11108 /* We don't need the local specializations any more. */
11112 /* Finish the function. */
11115 }
11117 /* We're not deferring instantiation any more. */
11123 out:
11131 }
11133 /* Run through the list of templates that we wish we could
11134 instantiate, and instantiate any we can. */
11136 int
11138 {
11145 do
11146 {
11151 {
11157 {
11158 tree fn;
11161 {
11165 fn;
11170 {
11173 }
11174 }
11177 /* If INSTANTIATION has been instantiated, then we don't
11178 need to consider it again in the future. */
11180 else
11181 {
11184 }
11185 }
11186 else
11187 {
11190 {
11194 {
11197 }
11198 }
11202 /* If INSTANTIATION has been instantiated, then we don't
11203 need to consider it again in the future. */
11205 else
11206 {
11209 }
11210 }
11213 }
11215 }
11220 }
11222 /* Substitute ARGVEC into T, which is a list of initializers for
11223 either base class or a non-static data member. The TREE_PURPOSEs
11224 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11225 instantiate_decl. */
11227 static tree
11229 {
11233 {
11234 tree decl;
11235 tree init;
11236 tree val;
11239 NULL_TREE);
11245 NULL_TREE);
11247 ;
11257 {
11261 }
11262 }
11264 }
11266 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11268 static void
11270 {
11275 else
11277 }
11279 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11280 is the instantiation (which should have been created with
11281 start_enum) and ARGS are the template arguments to use. */
11283 static void
11285 {
11286 tree e;
11289 {
11290 tree value;
11291 tree decl;
11294 /* Note that in a template enum, the TREE_VALUE is the
11295 CONST_DECL, not the corresponding INTEGER_CST. */
11298 NULL_TREE);
11300 /* Give this enumeration constant the correct access. */
11303 /* Actually build the enumerator itself. */
11305 }
11310 }
11312 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11313 its type -- but without substituting the innermost set of template
11314 arguments. So, innermost set of template parameters will appear in
11315 the type. */
11317 tree
11319 {
11320 tree fn_type;
11321 tree tmpl;
11322 tree targs;
11323 tree tparms;
11331 /* There should be as many levels of arguments as there are levels
11332 of parameters. */
11338 /* No substitution is necessary. */
11339 ;
11340 else
11341 {
11343 tree partial_args;
11345 /* Replace the innermost level of the TARGS with NULL_TREEs to
11346 let tsubst know not to substitute for those parameters. */
11355 /* Make sure that we can see identifiers, and compute access
11356 correctly. We can just use the context of DECL for the
11357 partial substitution here. It depends only on outer template
11358 parameters, regardless of whether the innermost level is
11359 specialized or not. */
11363 /* Now, do the (partial) substitution to figure out the
11364 appropriate function type. */
11368 /* Substitute into the template parameters to obtain the real
11369 innermost set of parameters. This step is important if the
11370 innermost set of template parameters contains value
11371 parameters whose types depend on outer template parameters. */
11376 }
11379 }
11381 /* Return truthvalue if we're processing a template different from
11382 the last one involved in diagnostics. */
11383 int
11385 {
11387 }
11389 /* Remember current template involved in diagnostics. */
11390 void
11392 {
11394 }
11396 tree
11398 {
11400 }
11402 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11403 type. Return zero for ok, nonzero for disallowed. Issue error and
11404 warning messages under control of COMPLAIN. */
11406 static int
11408 {
11422 type);
11424 }
11426 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11427 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11429 static bool
11431 {
11432 tree scope;
11434 /* [temp.dep.type]
11436 A type is dependent if it is:
11438 -- a template parameter. */
11441 /* -- a qualified-id with a nested-name-specifier which contains a
11442 class-name that names a dependent type or whose unqualified-id
11443 names a dependent type. */
11446 /* -- a cv-qualified type where the cv-unqualified type is
11447 dependent. */
11449 /* -- a compound type constructed from any dependent type. */
11459 {
11460 tree arg_type;
11465 arg_type;
11470 }
11471 /* -- an array type constructed from any dependent type or whose
11472 size is specified by a constant expression that is
11473 value-dependent. */
11475 {
11477 && ((value_dependent_expression_p
11479 || (type_dependent_expression_p
11483 }
11485 /* -- a template-id in which either the template name is a template
11486 parameter ... */
11489 /* ... or any of the template arguments is a dependent type or
11490 an expression that is type-dependent or value-dependent. */
11492 && (any_dependent_template_arguments_p
11496 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11497 expression is not type-dependent, then it should already been
11498 have resolved. */
11502 /* The standard does not specifically mention types that are local
11503 to template functions or local classes, but they should be
11504 considered dependent too. For example:
11506 template <int I> void f() {
11507 enum E { a = I };
11508 S<sizeof (E)> s;
11509 }
11511 The size of `E' cannot be known until the value of `I' has been
11512 determined. Therefore, `E' must be considered dependent. */
11519 /* Other types are non-dependent. */
11521 }
11523 /* Returns TRUE if TYPE is dependent, in the sense of
11524 [temp.dep.type]. */
11526 bool
11528 {
11529 /* If there are no template parameters in scope, then there can't be
11530 any dependent types. */
11534 /* If the type is NULL, we have not computed a type for the entity
11535 in question; in that case, the type is dependent. */
11539 /* Erroneous types can be considered non-dependent. */
11543 /* If we have not already computed the appropriate value for TYPE,
11544 do so now. */
11546 {
11549 }
11552 }
11554 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11556 static bool
11558 {
11559 tree scope;
11560 tree name;
11570 /* [temp.dep.expr]
11572 An id-expression is type-dependent if it contains a
11573 nested-name-specifier that contains a class-name that names a
11574 dependent type. */
11575 /* The suggested resolution to Core Issue 2 implies that if the
11576 qualifying type is the current class, then we must peek
11577 inside it. */
11586 }
11588 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11589 [temp.dep.constexpr] */
11591 bool
11593 {
11597 /* A name declared with a dependent type. */
11602 /* A non-type template parameter. */
11607 /* A constant with integral or enumeration type and is initialized
11608 with an expression that is value-dependent. */
11614 /* These expressions are value-dependent if the type to which the
11615 cast occurs is dependent or the expression being casted is
11616 value-dependent. */
11622 {
11625 /* A functional cast has a list of operands. */
11628 {
11629 do
11630 {
11634 }
11637 }
11638 else
11640 }
11641 /* A `sizeof' expression is value-dependent if the operand is
11642 type-dependent. */
11645 {
11650 }
11656 /* A constant expression is value-dependent if any subexpression is
11657 value-dependent. */
11659 {
11661 {
11669 || (value_dependent_expression_p
11672 {
11675 /* In some cases, some of the operands may be missing.
11676 (For example, in the case of PREDECREMENT_EXPR, the
11677 amount to increment by may be missing.) That doesn't
11678 make the expression dependent. */
11680 && (value_dependent_expression_p
11684 }
11685 }
11686 }
11688 /* The expression is not value-dependent. */
11690 }
11692 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11693 [temp.dep.expr]. */
11695 bool
11697 {
11704 /* An unresolved name is always dependent. */
11708 /* Some expression forms are never type-dependent. */
11718 /* The types of these expressions depends only on the type to which
11719 the cast occurs. */
11727 /* The types of these expressions depends only on the type created
11728 by the expression. */
11731 {
11732 /* For NEW_EXPR tree nodes created inside a template, either
11733 the object type itself or a TREE_LIST may appear as the
11734 operand 1. */
11737 /* This is an array type. We need to check array dimensions
11738 as well. */
11740 || value_dependent_expression_p
11742 else
11744 }
11748 type_dependent_expression_p))
11754 && (any_dependent_template_arguments_p
11759 {
11763 {
11769 }
11774 {
11779 }
11781 {
11783 {
11787 }
11789 }
11791 }
11794 }
11796 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11797 contains a type-dependent expression. */
11799 bool
11801 {
11803 {
11809 }
11811 }
11813 /* Returns TRUE if the ARG (a template argument) is dependent. */
11815 static bool
11817 {
11826 else
11829 }
11831 /* Returns true if ARGS (a collection of template arguments) contains
11832 any dependent arguments. */
11834 bool
11836 {
11847 }
11849 /* Returns TRUE if the template TMPL is dependent. */
11851 bool
11853 {
11855 {
11857 {
11861 }
11863 }
11865 /* Template template parameters are dependent. */
11869 /* So are qualified names that have not been looked up. */
11872 /* So are member templates of dependent classes. */
11876 }
11878 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11880 bool
11882 {
11885 }
11887 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11888 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11889 can be found. Note that this function peers inside uninstantiated
11890 templates and therefore should be used only in extremely limited
11891 situations. */
11893 tree
11895 {
11896 tree scope;
11897 tree name;
11898 tree decl;
11907 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11908 it first before we can figure out what NAME refers to. */
11911 /* If we don't know what SCOPE refers to, then we cannot resolve the
11912 TYPENAME_TYPE. */
11915 /* If the SCOPE is a template type parameter, we have no way of
11916 resolving the name. */
11919 /* If the SCOPE is not the current instantiation, there's no reason
11920 to look inside it. */
11923 /* If SCOPE is a partial instantiation, it will not have a valid
11924 TYPE_FIELDS list, so use the original template. */
11926 /* Enter the SCOPE so that name lookup will be resolved as if we
11927 were in the class definition. In particular, SCOPE will no
11928 longer be considered a dependent type. */
11930 /* Look up the declaration. */
11932 /* Obtain the set of qualifiers applied to the TYPE. */
11934 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11935 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11943 {
11944 tree tmpl;
11945 tree args;
11946 /* Obtain the template and the arguments. */
11949 /* Instantiate the template. */
11952 }
11953 else
11955 /* Qualify the resulting type. */
11958 /* Leave the SCOPE. */
11962 }
11964 /* EXPR is an expression which is not type-dependent. Return a proxy
11965 for EXPR that can be used to compute the types of larger
11966 expressions containing EXPR. */
11968 tree
11970 {
11971 /* Preserve null pointer constants so that the type of things like
11972 "p == 0" where "p" is a pointer can be determined. */
11975 /* Preserve OVERLOADs; the functions must be available to resolve
11976 types. */
11979 /* Preserve string constants; conversions from string constants to
11980 "char *" are allowed, even though normally a "const char *"
11981 cannot be used to initialize a "char *". */
12000 /* Otherwise, build a NON_DEPENDENT_EXPR.
12002 REFERENCE_TYPEs are not stripped for expressions in templates
12003 because doing so would play havoc with mangling. Consider, for
12004 example:
12006 template <typename T> void f<T& g>() { g(); }
12008 In the body of "f", the expression for "g" will have
12009 REFERENCE_TYPE, even though the standard says that it should
12010 not. The reason is that we must preserve the syntactic form of
12011 the expression so that mangling (say) "f<g>" inside the body of
12012 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12013 stripped here. */
12015 }
12017 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12018 Return a new TREE_LIST with the various arguments replaced with
12019 equivalent non-dependent expressions. */
12021 tree
12023 {
12024 tree a;
12025 tree new_args;
12031 new_args);
12033 }