| blob | ac5e4e1c8ef37a04194005cad7ab81be24d404be |
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
53 work. The TREE_PURPOSE of each entry is a SRCLOC indicating where
54 the instantiate request occurred; the TREE_VALUE is either a DECL
55 (for a function or static data member), or a TYPE (for a class)
56 indicating what we are hoping to instantiate. */
71 /* A map from local variable declarations in the body of the template
72 presently being instantiated to the corresponding instantiated
73 local variables. */
76 #define UNIFY_ALLOW_NONE 0
77 #define UNIFY_ALLOW_MORE_CV_QUAL 1
78 #define UNIFY_ALLOW_LESS_CV_QUAL 2
79 #define UNIFY_ALLOW_DERIVED 4
80 #define UNIFY_ALLOW_INTEGER 8
81 #define UNIFY_ALLOW_OUTER_LEVEL 16
82 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
83 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
84 #define UNIFY_ALLOW_MAX_CORRECTION 128
87 virtual, or a base class of a virtual
88 base. */
90 type with the desired type. */
114 tree*));
181 /* Make the current scope suitable for access checking when we are
182 processing T. T can be FUNCTION_DECL for instantiated function
183 template, TEMPLATE_DECL for uninstantiated one, or VAR_DECL for
184 static member variable (need by instantiate_decl). ARGS is the
185 template argument for TEMPLATE_DECL. If CONTEXT is not NULL_TREE,
186 this is used instead of the context of T. */
188 void
191 {
193 {
194 /* When we are processing specialization `foo<Outer>' for code like
196 template <class U> typename U::Inner foo ();
197 class Outer {
198 struct Inner {};
199 friend Outer::Inner foo<Outer> ();
200 };
202 `T' is a TEMPLATE_DECL, but `Outer' is only a friend of one of
203 its specialization. We can get the FUNCTION_DECL with the right
204 information because this specialization has already been
205 registered by the friend declaration above. */
208 {
209 tree full_args = tsubst_template_arg_vector
216 }
217 }
223 else
227 {
228 saved_access_scope = tree_cons
231 }
232 }
234 /* Like push_access_scope_real, but always uses DECL_CONTEXT. */
236 void
238 tree t;
239 {
241 }
243 /* Restore the scope set up by push_access_scope. T is the node we
244 are processing. */
246 void
248 tree t;
249 {
251 {
254 }
258 else
260 }
262 /* Do any processing required when DECL (a member template
263 declaration) is finished. Returns the TEMPLATE_DECL corresponding
264 to DECL, unless it is a specialization, in which case the DECL
265 itself is returned. */
267 tree
269 tree decl;
270 {
277 {
278 tree type;
284 {
288 }
290 }
294 {
296 {
299 }
300 else
302 }
303 else
307 }
309 /* Returns the template nesting level of the indicated class TYPE.
311 For example, in:
312 template <class T>
313 struct A
314 {
315 template <class U>
316 struct B {};
317 };
319 A<T>::B<U> has depth two, while A<T> has depth one.
320 Both A<T>::B<int> and A<int>::B<U> have depth one, if
321 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
322 specializations.
324 This function is guaranteed to return 0 if passed NULL_TREE so
325 that, for example, `template_class_depth (current_class_type)' is
326 always safe. */
328 static int
330 tree type;
332 {
339 {
341 {
344 && ((count_specializations
348 }
349 else
350 {
353 && ((count_specializations
357 }
358 }
361 }
363 /* Returns the template nesting level of the indicated class TYPE.
364 Like template_class_depth_real, but instantiations do not count in
365 the depth. */
367 int
369 tree type;
370 {
372 }
374 /* Returns 1 if processing DECL as part of do_pending_inlines
375 needs us to push template parms. */
377 static int
379 tree decl;
380 {
386 }
388 /* Subroutine of maybe_begin_member_template_processing.
389 Push the template parms in PARMS, starting from LEVELS steps into the
390 chain, and ending at the beginning, since template parms are listed
391 innermost first. */
393 static void
395 tree parmlist;
397 {
405 current_template_parms
412 {
417 {
424 {
425 /* Make a CONST_DECL as is done in process_template_parm.
426 It is ugly that we recreate this here; the original
427 version built in process_template_parm is no longer
428 available. */
435 }
440 }
441 }
442 }
444 /* Restore the template parameter context for a member template or
445 a friend template defined in a class definition. */
447 void
449 tree decl;
450 {
451 tree parms;
455 {
460 {
463 }
466 }
468 /* Remember how many levels of template parameters we pushed so that
469 we can pop them later. */
476 }
478 /* Undo the effects of begin_member_template_processing. */
480 void
482 {
492 {
496 }
497 }
499 /* Returns nonzero iff T is a member template function. We must be
500 careful as in
502 template <class T> class C { void f(); }
504 Here, f is a template function, and a member, but not a member
505 template. This function does not concern itself with the origin of
506 T, only its present state. So if we have
508 template <class T> class C { template <class U> void f(U); }
510 then neither C<int>::f<char> nor C<T>::f<double> is considered
511 to be a member template. But, `template <class U> void
512 C<int>::f(U)' is considered a member template. */
514 int
516 tree t;
517 {
519 /* Anything that isn't a function or a template function is
520 certainly not a member template. */
523 /* A local class can't have member templates. */
528 /* If there are more levels of template parameters than
529 there are template classes surrounding the declaration,
530 then we have a member template. */
533 }
536 /* Returns nonzero iff T is a member template class. See
537 is_member_template for a description of what precisely constitutes
538 a member template. */
540 int
542 tree t;
543 {
545 /* Anything that isn't a class template, is certainly not a member
546 template. */
550 /* Anything whose context isn't a class type is surely not a
551 member template. */
554 /* If there are more levels of template parameters than there are
555 template classes surrounding the declaration, then we have a
556 member template. */
559 }
560 #endif
562 /* Return a new template argument vector which contains all of ARGS,
563 but has as its innermost set of arguments the EXTRA_ARGS. */
565 static tree
567 tree args;
568 tree extra_args;
569 {
570 tree new_args;
585 }
587 /* Like add_to_template_args, but only the outermost ARGS are added to
588 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
589 (EXTRA_ARGS) levels are added. This function is used to combine
590 the template arguments from a partial instantiation with the
591 template arguments used to attain the full instantiation from the
592 partial instantiation. */
594 static tree
596 tree args;
597 tree extra_args;
598 {
599 tree new_args;
601 /* If there are more levels of EXTRA_ARGS than there are ARGS,
602 something very fishy is going on. */
606 /* If *all* the new arguments will be the EXTRA_ARGS, just return
607 them. */
611 /* For the moment, we make ARGS look like it contains fewer levels. */
616 /* Now, we restore ARGS to its full dimensions. */
620 }
622 /* Return the N levels of innermost template arguments from the ARGS. */
624 tree
626 tree args;
628 {
629 tree new_args;
635 /* If N is 1, just return the innermost set of template arguments. */
639 /* If we're not removing anything, just return the arguments we were
640 given. */
646 /* Make a new set of arguments, not containing the outer arguments. */
653 }
655 /* We've got a template header coming up; push to a new level for storing
656 the parms. */
658 void
660 {
661 /* We use a non-tag-transparent scope here, which causes pushtag to
662 put tags in this scope, rather than in the enclosing class or
663 namespace scope. This is the right thing, since we want
664 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
665 global template class, push_template_decl handles putting the
666 TEMPLATE_DECL into top-level scope. For a nested template class,
667 e.g.:
669 template <class T> struct S1 {
670 template <class T> struct S2 {};
671 };
673 pushtag contains special code to call pushdecl_with_scope on the
674 TEMPLATE_DECL for S2. */
679 }
681 /* This routine is called when a specialization is declared. If it is
682 invalid to declare a specialization here, an error is reported. */
684 static void
686 {
689 /* [temp.expl.spec]
691 An explicit specialization shall be declared in the namespace of
692 which the template is a member, or, for member templates, in the
693 namespace of which the enclosing class or enclosing class
694 template is a member. An explicit specialization of a member
695 function, member class or static data member of a class template
696 shall be declared in the namespace of which the class template
697 is a member. */
700 scope);
702 /* [temp.expl.spec]
704 In an explicit specialization declaration for a member of a class
705 template or a member template that appears in namespace scope,
706 the member template and some of its enclosing class templates may
707 remain unspecialized, except that the declaration shall not
708 explicitly specialize a class member template if its enclosing
709 class templates are not explicitly specialized as well. */
712 }
714 /* We've just seen template <>. */
716 void
718 {
722 }
724 /* Called at then end of processing a declaration preceded by
725 template<>. */
727 void
729 {
732 }
734 /* Any template <>'s that we have seen thus far are not referring to a
735 function specialization. */
737 void
739 {
742 }
744 /* We've just seen a template header. If SPECIALIZATION is nonzero,
745 it was of the form template <>. */
747 static void
750 {
752 template_header_count++;
753 }
755 /* We're beginning an explicit instantiation. */
757 void
759 {
762 }
765 void
767 {
770 }
772 /* The TYPE is being declared. If it is a template type, that means it
773 is a partial specialization. Do appropriate error-checking. */
775 void
777 tree type;
778 {
780 {
783 {
786 {
790 }
794 }
797 }
800 }
802 /* Retrieve the specialization (in the sense of [temp.spec] - a
803 specialization is either an instantiation or an explicit
804 specialization) of TMPL for the given template ARGS. If there is
805 no such specialization, return NULL_TREE. The ARGS are a vector of
806 arguments, or a vector of vectors of arguments, in the case of
807 templates with more than one level of parameters. */
809 static tree
811 tree tmpl;
812 tree args;
813 {
814 tree s;
818 /* There should be as many levels of arguments as there are
819 levels of parameters. */
831 }
833 /* Like retrieve_specialization, but for local declarations. */
835 static tree
837 tree tmpl;
838 {
839 tree spec =
843 }
845 /* Returns nonzero iff DECL is a specialization of TMPL. */
847 int
849 tree decl;
850 tree tmpl;
851 {
852 tree t;
855 {
861 }
862 else
863 {
872 }
875 }
877 /* Register the specialization SPEC as a specialization of TMPL with
878 the indicated ARGS. Returns SPEC, or an equivalent prior
879 declaration, if available. */
881 static tree
883 tree spec;
884 tree tmpl;
885 tree args;
886 {
887 tree s;
893 /* This is the FUNCTION_DECL for a partial instantiation. Don't
894 register it; we want the corresponding TEMPLATE_DECL instead.
895 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
896 the more obvious `uses_template_parms (spec)' to avoid problems
897 with default function arguments. In particular, given
898 something like this:
900 template <class T> void f(T t1, T t = T())
902 the default argument expression is not substituted for in an
903 instantiation unless and until it is actually needed. */
906 /* There should be as many levels of arguments as there are
907 levels of parameters. */
915 {
918 /* We can sometimes try to re-register a specialization that we've
919 already got. In particular, regenerate_decl_from_template
920 calls duplicate_decls which will update the specialization
921 list. But, we'll still get called again here anyhow. It's
922 more convenient to simply allow this than to try to prevent it. */
926 {
928 {
930 {
933 {
935 fn);
937 }
938 else
939 {
940 /* This situation should occur only if the first
941 specialization is an implicit instantiation,
942 the second is an explicit specialization, and
943 the implicit instantiation has not yet been
944 used. That situation can occur if we have
945 implicitly instantiated a member function and
946 then specialized it later.
948 We can also wind up here if a friend
949 declaration that looked like an instantiation
950 turns out to be a specialization:
952 template <class T> void foo(T);
953 class S { friend void foo<>(int) };
954 template <> void foo(int);
956 We transform the existing DECL in place so that
957 any pointers to it become pointers to the
958 updated declaration.
960 If there was a definition for the template, but
961 not for the specialization, we want this to
962 look as if there is no definition, and vice
963 versa. */
968 }
969 }
971 {
974 }
975 }
976 }
977 }
983 }
985 /* Unregister the specialization SPEC as a specialization of TMPL.
986 Returns nonzero if the SPEC was listed as a specialization of
987 TMPL. */
989 static int
991 tree spec;
992 tree tmpl;
993 {
1000 {
1003 }
1006 }
1008 /* Compare an entry in the local specializations hash table P1 (which
1009 is really a pointer to a TREE_LIST) with P2 (which is really a
1010 DECL). */
1012 static int
1014 {
1016 }
1018 /* Hash P1, an entry in the local specializations table. */
1020 static hashval_t
1022 {
1024 }
1026 /* Like register_specialization, but for local declarations. We are
1027 registering SPEC, an instantiation of TMPL. */
1029 static void
1031 tree spec;
1032 tree tmpl;
1033 {
1039 }
1041 /* Print the list of candidate FNS in an error message. */
1043 void
1045 tree fns;
1046 {
1047 tree fn;
1052 {
1053 tree f;
1058 }
1059 }
1061 /* Returns the template (one of the functions given by TEMPLATE_ID)
1062 which can be specialized to match the indicated DECL with the
1063 explicit template args given in TEMPLATE_ID. The DECL may be
1064 NULL_TREE if none is available. In that case, the functions in
1065 TEMPLATE_ID are non-members.
1067 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1068 specialization of a member template.
1070 The template args (those explicitly specified and those deduced)
1071 are output in a newly created vector *TARGS_OUT.
1073 If it is impossible to determine the result, an error message is
1074 issued. The error_mark_node is returned to indicate failure. */
1076 static tree
1078 need_member_template)
1079 tree template_id;
1080 tree decl;
1083 {
1084 tree fns;
1085 tree targs;
1086 tree explicit_targs;
1101 /* Check for baselinks. */
1106 {
1109 }
1112 {
1116 {
1117 tree decl_arg_types;
1119 /* DECL might be a specialization of FN. */
1121 /* Adjust the type of DECL in case FN is a static member. */
1127 /* Check that the number of function parameters matches.
1128 For example,
1129 template <class T> void f(int i = 0);
1130 template <> void f<int>();
1131 The specialization f<int> is invalid but is not caught
1132 by get_bindings below. */
1138 /* See whether this function might be a specialization of this
1139 template. */
1143 /* We cannot deduce template arguments that when used to
1144 specialize TMPL will produce DECL. */
1147 /* Save this template, and the arguments deduced. */
1149 }
1151 /* FN is an ordinary member function, and we need a
1152 specialization of a member template. */
1153 ;
1155 /* We can get IDENTIFIER_NODEs here in certain erroneous
1156 cases. */
1157 ;
1159 /* This is just an ordinary non-member function. Nothing can
1160 be a specialization of that. */
1161 ;
1163 /* Cannot specialize functions that are created implicitly. */
1164 ;
1165 else
1166 {
1167 tree decl_arg_types;
1169 /* This is an ordinary member function. However, since
1170 we're here, we can assume it's enclosing class is a
1171 template class. For example,
1173 template <typename T> struct S { void f(); };
1174 template <> void S<int>::f() {}
1176 Here, S<int>::f is a non-template, but S<int> is a
1177 template class. If FN has the same type as DECL, we
1178 might be in business. */
1181 /* Its enclosing class is an explicit specialization
1182 of a template class. This is not a candidate. */
1187 /* The return types differ. */
1190 /* Adjust the type of DECL in case FN is a static member. */
1197 decl_arg_types))
1198 /* They match! */
1200 }
1201 }
1204 {
1205 /* We have:
1207 [temp.expl.spec]
1209 It is possible for a specialization with a given function
1210 signature to be instantiated from more than one function
1211 template. In such cases, explicit specification of the
1212 template arguments must be used to uniquely identify the
1213 function template specialization being specialized.
1215 Note that here, there's no suggestion that we're supposed to
1216 determine which of the candidate templates is most
1217 specialized. However, we, also have:
1219 [temp.func.order]
1221 Partial ordering of overloaded function template
1222 declarations is used in the following contexts to select
1223 the function template to which a function template
1224 specialization refers:
1226 -- when an explicit specialization refers to a function
1227 template.
1229 So, we do use the partial ordering rules, at least for now.
1230 This extension can only serve to make invalid programs valid,
1231 so it's safe. And, there is strong anecdotal evidence that
1232 the committee intended the partial ordering rules to apply;
1233 the EDG front-end has that behavior, and John Spicer claims
1234 that the committee simply forgot to delete the wording in
1235 [temp.expl.spec]. */
1238 {
1241 }
1242 }
1245 {
1249 }
1253 {
1259 }
1261 /* We have one, and exactly one, match. */
1263 {
1264 /* It was a specialization of an ordinary member function in a
1265 template class. */
1268 }
1270 /* It was a specialization of a template. */
1273 {
1278 }
1279 else
1282 }
1284 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1285 but with the default argument values filled in from those in the
1286 TMPL_TYPES. */
1288 static tree
1290 tmpl_types)
1291 tree spec_types;
1292 tree tmpl_types;
1293 {
1294 tree new_spec_types;
1302 /* Substitute into the rest of the list. */
1303 new_spec_types =
1307 /* Add the default argument for this parameter. */
1310 new_spec_types);
1311 }
1313 /* DECL is an explicit specialization. Replicate default arguments
1314 from the template it specializes. (That way, code like:
1316 template <class T> void f(T = 3);
1317 template <> void f(double);
1318 void g () { f (); }
1320 works, as required.) An alternative approach would be to look up
1321 the correct default arguments at the call-site, but this approach
1322 is consistent with how implicit instantiations are handled. */
1324 static void
1326 tree decl;
1327 {
1328 tree tmpl;
1329 tree spec_types;
1330 tree tmpl_types;
1331 tree new_spec_types;
1332 tree old_type;
1333 tree new_type;
1334 tree t;
1339 /* See if there's anything we need to do. */
1352 {
1353 /* Remove the this pointer, but remember the object's type for
1354 CV quals. */
1360 {
1361 /* DECL may contain more parameters than TMPL due to the extra
1362 in-charge parameter in constructors and destructors. */
1365 }
1367 {
1370 }
1371 }
1373 /* Compute the merged default arguments. */
1374 new_spec_types =
1377 /* Compute the new FUNCTION_TYPE. */
1379 {
1383 new_spec_types);
1386 /* Put the in-charge parameter back. */
1389 new_spec_types);
1393 new_spec_types);
1394 }
1395 else
1397 new_spec_types);
1403 }
1405 /* Check to see if the function just declared, as indicated in
1406 DECLARATOR, and in DECL, is a specialization of a function
1407 template. We may also discover that the declaration is an explicit
1408 instantiation at this point.
1410 Returns DECL, or an equivalent declaration that should be used
1411 instead if all goes well. Issues an error message if something is
1412 amiss. Returns error_mark_node if the error is not easily
1413 recoverable.
1415 FLAGS is a bitmask consisting of the following flags:
1417 2: The function has a definition.
1418 4: The function is a friend.
1420 The TEMPLATE_COUNT is the number of references to qualifying
1421 template classes that appeared in the name of the function. For
1422 example, in
1424 template <class T> struct S { void f(); };
1425 void S<int>::f();
1427 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1428 classes are not counted in the TEMPLATE_COUNT, so that in
1430 template <class T> struct S {};
1431 template <> struct S<int> { void f(); }
1432 template <> void S<int>::f();
1434 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1435 invalid; there should be no template <>.)
1437 If the function is a specialization, it is marked as such via
1438 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1439 is set up correctly, and it is added to the list of specializations
1440 for that template. */
1442 tree
1444 tree declarator;
1445 tree decl;
1448 {
1456 tmpl_spec_kind tsk;
1461 {
1464 {
1467 }
1469 {
1471 /* This could be something like:
1473 template <class T> void f(T);
1474 class S { friend void f<>(int); } */
1476 else
1477 {
1478 /* This case handles bogus declarations like template <>
1479 template <class T> void f<int>(); */
1482 declarator);
1484 }
1485 }
1489 /* The error has already been reported in
1490 check_specialization_scope. */
1496 /* Fall through. */
1507 decl);
1510 /* Fall through. */
1515 else
1521 {
1523 decl);
1525 }
1530 {
1531 /* For backwards compatibility, we accept:
1533 template <class T> struct S { void f(); };
1534 void S<int>::f() {} // Missing template <>
1536 That used to be valid C++. */
1538 pedwarn
1542 }
1547 {
1548 /* This case handles bogus declarations like template <>
1549 template <class T> void f<int>(); */
1553 declarator);
1554 else
1556 declarator);
1558 }
1561 /* This is a specialization of a member template, without
1562 specialization the containing class. Something like:
1564 template <class T> struct S {
1565 template <class U> void f (U);
1566 };
1567 template <> template <class U> void S<int>::f(U) {}
1569 That's a specialization -- but of the entire template. */
1575 }
1578 {
1582 {
1583 pedwarn
1586 }
1589 }
1592 {
1596 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1598 {
1599 tree fns;
1605 else
1608 declarator =
1610 }
1616 {
1618 /* A specialization in class scope. This is invalid,
1619 but the error will already have been flagged by
1620 check_specialization_scope. */
1622 else
1623 {
1624 /* It's not valid to write an explicit instantiation in
1625 class scope, e.g.:
1627 class C { template void f(); }
1629 This case is caught by the parser. However, on
1630 something like:
1632 template class C { void f(); };
1634 (which is invalid) we can get here. The error will be
1635 issued later. */
1636 ;
1637 }
1640 }
1642 {
1643 /* A friend declaration. We can't do much, because we don't
1644 know what this resolves to, yet. */
1649 }
1652 IDENTIFIER_NODE))
1653 {
1654 /* Find the list of functions in ctype that have the same
1655 name as the declared function. */
1661 {
1666 {
1667 /* From [temp.expl.spec]:
1669 If such an explicit specialization for the member
1670 of a class template names an implicitly-declared
1671 special member function (clause _special_), the
1672 program is ill-formed.
1674 Similar language is found in [temp.explicit]. */
1677 }
1680 }
1683 {
1687 }
1688 else
1689 {
1690 tree methods;
1692 /* For a type-conversion operator, we cannot do a
1693 name-based lookup. We might be looking for `operator
1694 int' which will be a specialization of `operator T'.
1695 So, we find *all* the conversion operators, and then
1696 select from them. */
1703 {
1707 /* There are no more conversion functions. */
1710 /* Glue all these conversion functions together
1711 with those we already have. */
1714 }
1715 }
1718 {
1722 }
1723 else
1725 }
1727 /* Figure out what exactly is being specialized at this point.
1728 Note that for an explicit instantiation, even one for a
1729 member function, we cannot tell apriori whether the
1730 instantiation is for a member template, or just a member
1731 function of a template class. Even if a member template is
1732 being instantiated, the member template arguments may be
1733 elided if they can be deduced from the rest of the
1734 declaration. */
1737 member_specialization);
1740 /* We couldn't figure out what this declaration was
1741 specializing. */
1743 else
1744 {
1748 {
1749 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1750 is done by do_decl_instantiation later. */
1756 {
1757 /* If TMPL is not the most general template (for
1758 example, if TMPL is a friend template that is
1759 injected into namespace scope), then there will
1760 be too many levels of TARGS. Remove some of them
1761 here. */
1763 tree new_targs;
1770 }
1773 }
1775 /* If this is a specialization of a member template of a
1776 template class. In we want to return the TEMPLATE_DECL,
1777 not the specialization of it. */
1779 {
1783 }
1785 /* If we thought that the DECL was a member function, but it
1786 turns out to be specializing a static member function,
1787 make DECL a static member function as well. */
1790 {
1793 }
1795 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1798 /* Inherit default function arguments from the template
1799 DECL is specializing. */
1802 /* This specialization has the same protection as the
1803 template it specializes. */
1808 /* This is not really a declaration of a specialization.
1809 It's just the name of an instantiation. But, it's not
1810 a request for an instantiation, either. */
1813 /* This is indeed a specialization. In case of constructors
1814 and destructors, we need in-charge and not-in-charge
1815 versions in V3 ABI. */
1818 /* Register this specialization so that we can find it
1819 again. */
1821 }
1822 }
1825 }
1827 /* TYPE is being declared. Verify that the use of template headers
1828 and such is reasonable. Issue error messages if not. */
1830 void
1832 tree type;
1833 {
1835 {
1836 /* We are in the scope of some `template <...>' header. */
1838 int context_depth
1843 /* This is OK; the template headers are for the context. We
1844 are actually too lenient here; like
1845 check_explicit_specialization we should consider the number
1846 of template types included in the actual declaration. For
1847 example,
1849 template <class T> struct S {
1850 template <class U> template <class V>
1851 struct I {};
1852 };
1854 is invalid, but:
1856 template <class T> struct S {
1857 template <class U> struct I;
1858 };
1860 template <class T> template <class U.
1861 struct S<T>::I {};
1863 is not. */
1864 ;
1866 /* There are two many template parameter lists. */
1868 }
1869 }
1871 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1872 parameters. These are represented in the same format used for
1873 DECL_TEMPLATE_PARMS. */
1876 tree parms1;
1877 tree parms2;
1878 {
1879 tree p1;
1880 tree p2;
1888 {
1900 {
1911 }
1912 }
1915 /* One set of parameters has more parameters lists than the
1916 other. */
1920 }
1922 /* Complain if DECL shadows a template parameter.
1924 [temp.local]: A template-parameter shall not be redeclared within its
1925 scope (including nested scopes). */
1927 void
1929 tree decl;
1930 {
1931 tree olddecl;
1933 /* If we're not in a template, we can't possibly shadow a template
1934 parameter. */
1938 /* Figure out what we're shadowing. */
1943 /* If there's no previous binding for this name, we're not shadowing
1944 anything, let alone a template parameter. */
1948 /* If we're not shadowing a template parameter, we're done. Note
1949 that OLDDECL might be an OVERLOAD (or perhaps even an
1950 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1951 node. */
1955 /* We check for decl != olddecl to avoid bogus errors for using a
1956 name inside a class. We check TPFI to avoid duplicate errors for
1957 inline member templates. */
1964 }
1966 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1967 ORIG_LEVEL, DECL, and TYPE. */
1969 static tree
1974 tree decl;
1975 tree type;
1976 {
1985 }
1987 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1988 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1989 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1990 new one is created. */
1992 static tree
1994 tree index;
1995 tree type;
1997 {
2001 {
2002 tree decl
2005 type);
2006 tree t
2016 /* Template template parameters need this. */
2019 }
2022 }
2024 /* Process information from new template parameter NEXT and append it to the
2025 LIST being built. */
2027 tree
2030 {
2031 tree parm;
2033 tree defval;
2043 {
2048 else
2051 }
2052 else
2056 {
2058 /* is a const-param */
2063 /* [temp.param]
2065 The top-level cv-qualifiers on the template-parameter are
2066 ignored when determining its type. */
2069 /* A template parameter is not modifiable. */
2076 processing_template_decl,
2078 }
2079 else
2080 {
2081 tree t;
2085 {
2087 /* This is for distinguishing between real templates and template
2088 template parameters */
2092 }
2093 else
2094 {
2096 /* parm is either IDENTIFIER_NODE or NULL_TREE */
2098 }
2105 processing_template_decl,
2107 }
2113 }
2115 /* The end of a template parameter list has been reached. Process the
2116 tree list into a parameter vector, converting each parameter into a more
2117 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2118 as PARM_DECLs. */
2120 tree
2122 tree parms;
2123 {
2128 current_template_parms
2133 {
2137 }
2142 }
2144 /* end_template_decl is called after a template declaration is seen. */
2146 void
2148 {
2154 /* This matches the pushlevel in begin_template_parm_list. */
2159 }
2161 /* Given a template argument vector containing the template PARMS.
2162 The innermost PARMS are given first. */
2164 tree
2166 {
2167 tree header;
2172 /* If there is only one level of template parameters, we do not
2173 create a TREE_VEC of TREE_VECs. Instead, we return a single
2174 TREE_VEC containing the arguments. */
2179 {
2185 {
2188 /* T will be a list if we are called from within a
2189 begin/end_template_parm_list pair, but a vector directly
2190 if within a begin/end_member_template_processing pair. */
2192 {
2198 else
2201 }
2202 }
2206 else
2208 }
2211 }
2213 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2214 template PARMS. Used by push_template_decl below. */
2216 static tree
2218 tree decl;
2219 tree parms;
2220 {
2225 {
2234 }
2237 }
2239 struct template_parm_data
2240 {
2241 /* The level of the template parameters we are currently
2242 processing. */
2245 /* The index of the specialization argument we are currently
2246 processing. */
2249 /* An array whose size is the number of template parameters. The
2250 elements are nonzero if the parameter has been used in any one
2251 of the arguments processed so far. */
2254 /* An array whose size is the number of template arguments. The
2255 elements are nonzero if the argument makes use of template
2256 parameters of this level. */
2258 };
2260 /* Subroutine of push_template_decl used to see if each template
2261 parameter in a partial specialization is used in the explicit
2262 argument list. If T is of the LEVEL given in DATA (which is
2263 treated as a template_parm_data*), then DATA->PARMS is marked
2264 appropriately. */
2266 static int
2268 tree t;
2270 {
2276 {
2279 }
2280 else
2281 {
2284 }
2287 {
2290 }
2292 /* Return zero so that for_each_template_parm will continue the
2293 traversal of the tree; we want to mark *every* template parm. */
2295 }
2297 /* Process the partial specialization DECL. */
2299 static tree
2301 tree decl;
2302 {
2316 /* We check that each of the template parameters given in the
2317 partial specialization is used in the argument list to the
2318 specialization. For example:
2320 template <class T> struct S;
2321 template <class T> struct S<T*>;
2323 The second declaration is OK because `T*' uses the template
2324 parameter T, whereas
2326 template <class T> struct S<int>;
2328 is no good. Even trickier is:
2330 template <class T>
2331 struct S1
2332 {
2333 template <class U>
2334 struct S2;
2335 template <class U>
2336 struct S2<T>;
2337 };
2339 The S2<T> declaration is actually invalid; it is a
2340 full-specialization. Of course,
2342 template <class U>
2343 struct S2<T (*)(U)>;
2345 or some such would have been OK. */
2353 {
2358 NULL);
2359 }
2362 {
2363 /* One of the template parms was not used in the
2364 specialization. */
2366 {
2369 }
2373 }
2375 /* [temp.class.spec]
2377 The argument list of the specialization shall not be identical to
2378 the implicit argument list of the primary template. */
2385 /* [temp.class.spec]
2387 A partially specialized non-type argument expression shall not
2388 involve template parameters of the partial specialization except
2389 when the argument expression is a simple identifier.
2391 The type of a template parameter corresponding to a specialized
2392 non-type argument shall not be dependent on a parameter of the
2393 specialization. */
2397 {
2402 /* This next line is the `argument expression is not just a
2403 simple identifier' condition and also the `specialized
2404 non-type argument' bit. */
2406 {
2409 else
2410 {
2411 /* Look at the corresponding template parameter,
2412 marking which template parameters its type depends
2413 upon. */
2414 tree type =
2416 i)));
2419 {
2420 /* We haven't yet initialized TPD2. Do so now. */
2421 tpd2.arg_uses_template_parms
2423 /* The number of parameters here is the number in the
2424 main template, which, as checked in the assertion
2425 above, is NARGS. */
2429 }
2431 /* Mark the template parameters. But this time, we're
2432 looking for the template parameters of the main
2433 template, not in the specialization. */
2440 NULL);
2443 {
2444 /* The type depended on some template parameters.
2445 If they are fully specialized in the
2446 specialization, that's OK. */
2451 {
2453 type,
2454 arg);
2456 }
2457 }
2458 }
2459 }
2460 }
2463 /* We've already got this specialization. */
2471 }
2473 /* Check that a template declaration's use of default arguments is not
2474 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2475 nonzero if DECL is the thing declared by a primary template.
2476 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2478 static void
2480 tree decl;
2481 tree parms;
2484 {
2487 tree parm_level;
2489 /* [temp.param]
2491 A default template-argument shall not be specified in a
2492 function template declaration or a function template definition, nor
2493 in the template-parameter-list of the definition of a member of a
2494 class template. */
2497 /* You can't have a function template declaration in a local
2498 scope, nor you can you define a member of a class template in a
2499 local scope. */
2505 /* If this is either a friend defined in the scope of the class
2506 or a member function. */
2511 current_class_type)))
2512 /* And, if it was a member function, it really was defined in
2513 the scope of the class. */
2515 /* We already checked these parameters when the template was
2516 declared, so there's no need to do it again now. This function
2517 was defined in class scope, but we're processing it's body now
2518 that the class is complete. */
2521 /* [temp.param]
2523 If a template-parameter has a default template-argument, all
2524 subsequent template-parameters shall have a default
2525 template-argument supplied. */
2527 {
2534 {
2539 {
2541 /* For better subsequent error-recovery, we indicate that
2542 there should have been a default argument. */
2544 }
2545 }
2546 }
2549 /* For an ordinary class template, default template arguments are
2550 allowed at the innermost level, e.g.:
2551 template <class T = int>
2552 struct S {};
2553 but, in a partial specialization, they're not allowed even
2554 there, as we have in [temp.class.spec]:
2556 The template parameter list of a specialization shall not
2557 contain default template argument values.
2559 So, for a partial specialization, or for a function template,
2560 we look at all of them. */
2561 ;
2562 else
2563 /* But, for a primary class template that is not a partial
2564 specialization we look at all template parameters except the
2565 innermost ones. */
2568 /* Figure out what error message to issue. */
2573 else
2577 /* If we're inside a class definition, there's no need to
2578 examine the parameters to the class itself. On the one
2579 hand, they will be checked when the class is defined, and,
2580 on the other, default arguments are valid in things like:
2581 template <class T = double>
2582 struct S { template <class U> void f(U); };
2583 Here the default argument for `S' has no bearing on the
2584 declaration of `f'. */
2586 else
2587 /* Check everything. */
2593 {
2601 {
2603 {
2606 }
2608 /* Clear out the default argument so that we are not
2609 confused later. */
2611 }
2613 /* At this point, if we're still interested in issuing messages,
2614 they must apply to classes surrounding the object declared. */
2617 }
2618 }
2620 /* Worker for push_template_decl_real, called via
2621 for_each_template_parm. DATA is really an int, indicating the
2622 level of the parameters we are interested in. If T is a template
2623 parameter of that level, return nonzero. */
2625 static int
2627 tree t;
2629 {
2635 else
2638 }
2640 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2641 parameters given by current_template_args, or reuses a
2642 previously existing one, if appropriate. Returns the DECL, or an
2643 equivalent one, if it is replaced via a call to duplicate_decls.
2645 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2647 tree
2649 tree decl;
2651 {
2652 tree tmpl;
2653 tree args;
2654 tree info;
2655 tree ctx;
2660 /* See if this is a partial specialization. */
2668 /* For a friend, we want the context of the friend function, not
2669 the type of which it is a friend. */
2673 /* In the case of a virtual function, we want the class in which
2674 it is defined. */
2676 else
2677 /* Otherwise, if we're currently defining some class, the DECL
2678 is assumed to be a member of the class. */
2687 /* See if this is a primary template. */
2691 {
2702 else
2704 }
2706 /* Check to see that the rules regarding the use of default
2707 arguments are not being violated. */
2720 {
2725 /* If DECL is a TYPE_DECL for a class-template, then there won't
2726 be DECL_LANG_SPECIFIC. The information equivalent to
2727 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2731 {
2732 /* Since a template declaration already existed for this
2733 class-type, we must be redeclaring it here. Make sure
2734 that the redeclaration is valid. */
2736 current_template_parms);
2737 /* We don't need to create a new TEMPLATE_DECL; just use the
2738 one we already had. */
2740 }
2741 else
2742 {
2748 {
2749 /* A specialization of a member template of a template
2750 class. */
2754 }
2755 }
2756 }
2757 else
2758 {
2763 {
2769 else
2770 {
2773 }
2774 }
2776 {
2779 }
2780 else
2787 {
2788 tree new_tmpl;
2790 /* The declaration is a specialization of a member
2791 template, declared outside the class. Therefore, the
2792 innermost template arguments will be NULL, so we
2793 replace them with the arguments determined by the
2794 earlier call to check_explicit_specialization. */
2797 new_tmpl
2808 args);
2810 }
2812 /* Make sure the template headers we got make sense. */
2817 {
2820 }
2821 else
2823 {
2828 {
2832 else
2836 }
2838 /* Perhaps we should also check that the parms are used in the
2839 appropriate qualifying scopes in the declarator? */
2843 else
2845 }
2846 }
2851 /* Push template declarations for global functions and types. Note
2852 that we do not try to push a global template friend declared in a
2853 template class; such a thing may well depend on the template
2854 parameters of the class. */
2860 {
2863 {
2866 /* It is a conversion operator. See if the type converted to
2867 depends on innermost template operands. */
2870 template_parm_this_level_p,
2872 NULL))
2874 }
2875 }
2880 {
2884 /* Don't change the name if we've already set it up. */
2887 }
2892 }
2894 tree
2896 tree decl;
2897 {
2899 }
2901 /* Called when a class template TYPE is redeclared with the indicated
2902 template PARMS, e.g.:
2904 template <class T> struct S;
2905 template <class T> struct S {}; */
2907 void
2909 tree type;
2910 tree parms;
2911 {
2912 tree tmpl;
2913 tree tmpl_parms;
2917 {
2920 }
2924 /* The type is nested in some template class. Nothing to worry
2925 about here; there are no new template parameters for the nested
2926 type. */
2933 {
2940 }
2943 {
2950 {
2954 }
2957 {
2958 /* We have in [temp.param]:
2960 A template-parameter may not be given default arguments
2961 by two different declarations in the same scope. */
2965 }
2968 /* Update the previous template parameters (which are the ones
2969 that will really count) with the new default value. */
2972 /* Update the new parameters, too; they'll be used as the
2973 parameters for any members. */
2975 }
2976 }
2978 /* Attempt to convert the non-type template parameter EXPR to the
2979 indicated TYPE. If the conversion is successful, return the
2980 converted value. If the conversion is unsuccessful, return
2981 NULL_TREE if we issued an error message, or error_mark_node if we
2982 did not. We issue error messages for out-and-out bad template
2983 parameters, but not simply because the conversion failed, since we
2984 might be just trying to do argument deduction. By the time this
2985 function is called, neither TYPE nor EXPR may make use of template
2986 parameters. */
2988 static tree
2990 tree type;
2991 tree expr;
2992 {
2995 /* A template-argument for a non-type, non-template
2996 template-parameter shall be one of:
2998 --an integral constant-expression of integral or enumeration
2999 type; or
3001 --the name of a non-type template-parameter; or
3003 --the name of an object or function with external linkage,
3004 including function templates and function template-ids but
3005 excluding non-static class members, expressed as id-expression;
3006 or
3008 --the address of an object or function with external linkage,
3009 including function templates and function template-ids but
3010 excluding non-static class members, expressed as & id-expression
3011 where the & is optional if the name refers to a function or
3012 array; or
3014 --a pointer to member expressed as described in _expr.unary.op_. */
3016 /* An integral constant-expression can include const variables or
3017 enumerators. Simplify things by folding them to their values,
3018 unless we're about to bind the declaration to a reference
3019 parameter. */
3025 /* OK for now. We'll check that it has external linkage later.
3026 Check this first since if expr_type is the unknown_type_node
3027 we would otherwise complain below. */
3028 ;
3031 {
3034 }
3039 /* If expr is the address of an overloaded function, we
3040 will get the unknown_type_node at this point. */
3042 {
3043 tree referent;
3051 else
3052 {
3054 {
3055 bad_argument:
3058 {
3061 else
3063 }
3069 }
3073 }
3076 {
3077 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3078 referent);
3080 }
3083 /* We'll check that it has external linkage later. */
3084 ;
3088 {
3091 }
3092 }
3096 {
3098 {
3099 non_constant:
3101 expr);
3103 }
3104 }
3105 else
3106 {
3109 }
3112 {
3116 /* For a non-type template-parameter of integral or enumeration
3117 type, integral promotions (_conv.prom_) and integral
3118 conversions (_conv.integral_) are applied. */
3122 /* It's safe to call digest_init in this case; we know we're
3123 just converting one integral constant expression to another. */
3127 /* Curiously, some TREE_CONSTANT integral expressions do not
3128 simplify to integer constants. For example, `3 % 0',
3129 remains a TRUNC_MOD_EXPR. */
3135 {
3139 {
3140 tree e;
3142 /* For a non-type template-parameter of type pointer to data
3143 member, qualification conversions (_conv.qual_) are
3144 applied. */
3147 /* The call to perform_qualification_conversions will
3148 insert a NOP_EXPR over EXPR to do express conversion,
3149 if necessary. But, that will confuse us if we use
3150 this (converted) template parameter to instantiate
3151 another template; then the thing will not look like a
3152 valid template argument. So, just make a new
3153 constant, of the appropriate type. */
3156 }
3158 {
3159 /* For a non-type template-parameter of type pointer to
3160 function, only the function-to-pointer conversion
3161 (_conv.func_) is applied. If the template-argument
3162 represents a set of overloaded functions (or a pointer to
3163 such), the matching function is selected from the set
3164 (_over.over_). */
3165 tree fns;
3166 tree fn;
3170 else
3179 {
3182 else
3184 }
3191 }
3192 else
3193 {
3194 /* For a non-type template-parameter of type pointer to
3195 object, qualification conversions (_conv.qual_) and the
3196 array-to-pointer conversion (_conv.array_) are applied.
3197 [Note: In particular, neither the null pointer conversion
3198 (_conv.ptr_) nor the derived-to-base conversion
3199 (_conv.ptr_) are applied. Although 0 is a valid
3200 template-argument for a non-type template-parameter of
3201 integral type, it is not a valid template-argument for a
3202 non-type template-parameter of pointer type.]
3204 The call to decay_conversion performs the
3205 array-to-pointer conversion, if appropriate. */
3210 else
3212 }
3213 }
3217 {
3220 /* If this expression already has reference type, get the
3221 underling object. */
3223 {
3227 }
3230 {
3231 /* For a non-type template-parameter of type reference to
3232 function, no conversions apply. If the
3233 template-argument represents a set of overloaded
3234 functions, the matching function is selected from the
3235 set (_over.over_). */
3236 tree fn;
3244 {
3246 /* Don't issue an error here; we might get a different
3247 function if the overloading had worked out
3248 differently. */
3250 else
3252 }
3259 }
3260 else
3261 {
3262 /* For a non-type template-parameter of type reference to
3263 object, no conversions apply. The type referred to by the
3264 reference may be more cv-qualified than the (otherwise
3265 identical) type of the template-argument. The
3266 template-parameter is bound directly to the
3267 template-argument, which must be an lvalue. */
3271 expr_type)
3274 }
3278 }
3282 {
3285 /* For a non-type template-parameter of type pointer to member
3286 function, no conversions apply. If the template-argument
3287 represents a set of overloaded member functions, the
3288 matching member function is selected from the set
3289 (_over.over_). */
3296 {
3297 /* A ptr-to-member constant. */
3300 else
3302 }
3315 }
3319 /* All non-type parameters must have one of these types. */
3322 }
3325 }
3327 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3328 template template parameters. Both PARM_PARMS and ARG_PARMS are
3329 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3330 or PARM_DECL.
3332 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3333 the case, then extra parameters must have default arguments.
3335 Consider the example:
3336 template <class T, class Allocator = allocator> class vector;
3337 template<template <class U> class TT> class C;
3339 C<vector> is a valid instantiation. PARM_PARMS for the above code
3340 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3341 T and Allocator) and OUTER_ARGS contains the argument that is used to
3342 substitute the TT parameter. */
3344 static int
3348 tsubst_flags_t complain;
3350 {
3360 /* The rule here is opposite of coerce_template_parms. */
3367 {
3379 {
3384 /* We encounter instantiations of templates like
3385 template <template <template <class> class> class TT>
3386 class C; */
3387 {
3393 outer_args))
3395 }
3399 /* The tsubst call is used to handle cases such as
3400 template <class T, template <T> class TT> class D;
3401 i.e. the parameter list of TT depends on earlier parameters. */
3410 }
3411 }
3413 }
3415 /* Convert the indicated template ARG as necessary to match the
3416 indicated template PARM. Returns the converted ARG, or
3417 error_mark_node if the conversion was unsuccessful. Error and
3418 warning messages are issued under control of COMPLAIN. This
3419 conversion is for the Ith parameter in the parameter list. ARGS is
3420 the full set of template arguments deduced so far. */
3422 static tree
3424 tree parm;
3425 tree arg;
3426 tree args;
3427 tsubst_flags_t complain;
3429 tree in_decl;
3430 {
3431 tree val;
3432 tree inner_args;
3440 {
3441 /* The template argument was the name of some
3442 member function. That's usually
3443 invalid, but static members are OK. In any
3444 case, grab the underlying fields/functions
3445 and issue an error later if required. */
3448 }
3461 {
3463 /* This is a template name used within the scope of the
3464 template. It could be the template, or it could be the
3465 instantiation. Choose whichever makes sense. */
3467 else
3469 }
3470 else
3471 /* It is a non-template class, or a specialization of a template
3472 class, or a non-template member of a template class. */
3486 {
3493 }
3495 {
3497 {
3499 {
3506 else
3508 }
3509 }
3511 }
3513 {
3515 {
3520 else
3522 }
3524 }
3527 {
3529 {
3531 /* The number of argument required is not known yet.
3532 Just accept it for now. */
3534 else
3535 {
3541 inner_args))
3542 {
3545 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3546 TEMPLATE_DECL. */
3550 }
3551 else
3552 {
3554 {
3558 }
3561 }
3562 }
3563 }
3564 else
3565 {
3568 {
3569 /* [basic.link]: A name with no linkage (notably, the
3570 name of a class or enumeration declared in a local
3571 scope) shall not be used to declare an entity with
3572 linkage. This implies that names with no linkage
3573 cannot be used as template arguments. */
3576 {
3578 pedwarn
3580 else
3581 error
3585 }
3587 /* In order to avoid all sorts of complications, we do
3588 not allow variably-modified types as template
3589 arguments. */
3591 {
3593 val);
3595 }
3596 }
3597 }
3598 }
3599 else
3600 {
3610 /* We used to call digest_init here. However, digest_init
3611 will report errors, which we don't want when complain
3612 is zero. More importantly, digest_init will try too
3613 hard to convert things: for example, `0' should not be
3614 converted to pointer type at this point according to
3615 the standard. Accepting this is not merely an
3616 extension, since deciding whether or not these
3617 conversions can occur is part of determining which
3618 function template to call, or whether a given explicit
3619 argument specification is valid. */
3621 else
3629 }
3632 }
3634 /* Convert all template arguments to their appropriate types, and
3635 return a vector containing the innermost resulting template
3636 arguments. If any error occurs, return error_mark_node. Error and
3637 warning messages are issued under control of COMPLAIN. Some error
3638 messages are issued even if COMPLAIN is zero; for instance, if a
3639 template argument is composed from a local class.
3641 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3642 provided in ARGLIST, or else trailing parameters must have default
3643 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3644 deduction for any unspecified trailing arguments. */
3646 static tree
3648 complain,
3649 require_all_arguments)
3651 tree in_decl;
3652 tsubst_flags_t complain;
3654 {
3656 tree inner_args;
3657 tree new_args;
3658 tree new_inner_args;
3666 && require_all_arguments
3668 {
3670 {
3676 }
3679 }
3684 {
3685 tree arg;
3686 tree parm;
3688 /* Get the Ith template parameter. */
3691 /* Calculate the Ith argument. */
3693 {
3696 }
3699 /* If no template argument was supplied, look for a default
3700 value. */
3702 {
3703 /* There was no default value. */
3706 }
3709 else
3711 in_decl);
3713 /* Now, convert the Ith argument, as necessary. */
3715 /* We're out of arguments. */
3716 {
3719 }
3721 {
3724 }
3725 else
3728 in_decl);
3731 lost++;
3733 }
3739 }
3741 /* Returns 1 if template args OT and NT are equivalent. */
3743 static int
3746 {
3751 /* For member templates */
3757 else
3759 }
3761 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3762 of template arguments. Returns 0 otherwise. */
3764 int
3767 {
3774 {
3780 }
3782 }
3784 /* Given class template name and parameter list, produce a user-friendly name
3785 for the instantiation. */
3791 {
3798 else
3802 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3803 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3811 {
3819 {
3822 }
3824 {
3826 {
3827 /* Already substituted with real template. Just output
3828 the template name here */
3831 {
3832 /* The template may be defined in a namespace, or
3833 may be a member template. */
3839 }
3841 }
3842 else
3843 /* Output the parameter declaration */
3846 }
3847 else
3851 {
3852 /* New list cell was built because old chain link was in
3853 use. */
3856 }
3857 /* No need to check arglist against parmlist here; we did that
3858 in coerce_template_parms, called from lookup_template_class. */
3860 }
3861 {
3865 offset--;
3868 /* B<C<char> >, not B<C<char>> */
3871 }
3875 }
3877 static tree
3879 tree t;
3880 {
3882 /* Specializations have already had their names set up in
3883 lookup_template_class. */
3885 {
3888 /* For non-primary templates, the template parameters are
3889 implicit from their surrounding context. */
3891 {
3900 }
3901 }
3904 }
3906 static void
3908 tree d;
3909 {
3913 tree pt;
3919 /* We are called both from instantiate_decl, where we've already had a
3920 tinst_level pushed, and instantiate_template, where we haven't.
3921 Compensate. */
3930 else
3939 }
3942 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3943 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3944 documentation for TEMPLATE_ID_EXPR. */
3946 tree
3949 {
3950 tree type;
3956 {
3959 }
3969 {
3971 unknown_type_node,
3973 arglist);
3975 }
3982 }
3984 /* Within the scope of a template class S<T>, the name S gets bound
3985 (in build_self_reference) to a TYPE_DECL for the class, not a
3986 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3987 or one of its enclosing classes, and that type is a template,
3988 return the associated TEMPLATE_DECL. Otherwise, the original
3989 DECL is returned. */
3991 tree
3993 tree decl;
3994 {
4001 }
4003 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4004 parameters, find the desired type.
4006 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4007 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
4008 be a TREE_LIST if called directly from the parser, and a TREE_VEC
4009 otherwise.)
4011 IN_DECL, if non-NULL, is the template declaration we are trying to
4012 instantiate.
4014 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4015 the class we are looking up.
4017 Issue error and warning messages under control of COMPLAIN.
4019 If the template class is really a local class in a template
4020 function, then the FUNCTION_CONTEXT is the function in which it is
4021 being instantiated. */
4023 tree
4026 tree in_decl;
4027 tree context;
4029 tsubst_flags_t complain;
4030 {
4032 tree t;
4036 {
4040 else
4041 {
4048 }
4051 }
4053 {
4056 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4057 an implicit typename for the second A. Deal with it. */
4062 {
4065 }
4066 }
4069 {
4072 }
4075 {
4079 }
4081 /* With something like `template <class T> class X class X { ... };'
4082 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
4083 We don't want to do that, but we have to deal with the situation,
4084 so let's give them some syntax errors to chew on instead of a
4085 crash. Alternatively D1 might not be a template type at all. */
4087 {
4091 }
4094 /* If we're called from the parser, make sure it's a user visible
4095 template. */
4099 {
4101 {
4105 }
4107 }
4110 {
4111 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4112 template arguments */
4114 tree parm;
4115 tree arglist2;
4119 /* Consider an example where a template template parameter declared as
4121 template <class T, class U = std::allocator<T> > class TT
4123 The template parameter level of T and U are one level larger than
4124 of TT. To proper process the default argument of U, say when an
4125 instantiation `TT<int>' is seen, we need to build the full
4126 arguments containing {int} as the innermost level. Outer levels,
4127 available when not appearing as default template argument, can be
4128 obtained from `current_template_args ()'.
4130 Suppose that TT is later substituted with std::vector. The above
4131 instantiation is `TT<int, std::allocator<T> >' with TT at
4132 level 1, and T at level 2, while the template arguments at level 1
4133 becomes {std::vector} and the inner level 2 is {int}. */
4145 }
4146 else
4147 {
4149 tree gen_tmpl;
4150 tree type_decl;
4163 {
4164 /* We've been given an incomplete set of template arguments.
4165 For example, given:
4167 template <class T> struct S1 {
4168 template <class U> struct S2 {};
4169 template <class U> struct S2<U*> {};
4170 };
4172 we will be called with an ARGLIST of `U*', but the
4173 TEMPLATE will be `template <class T> template
4174 <class U> struct S1<T>::S2'. We must fill in the missing
4175 arguments. */
4176 arglist
4178 arglist);
4180 }
4182 /* Now we should have enough arguments. */
4185 /* From here on, we're only interested in the most general
4186 template. */
4189 /* Calculate the BOUND_ARGS. These will be the args that are
4190 actually tsubst'd into the definition to create the
4191 instantiation. */
4193 {
4194 /* We have multiple levels of arguments to coerce, at once. */
4204 {
4210 /* We temporarily reduce the length of the ARGLIST so
4211 that coerce_template_parms will see only the arguments
4212 corresponding to the template parameters it is
4213 examining. */
4215 }
4217 /* Restore the ARGLIST to its full size. */
4221 }
4222 else
4223 arglist
4230 /* We were unable to bind the arguments. */
4233 /* In the scope of a template class, explicit references to the
4234 template class refer to the type of the template, not any
4235 instantiation of it. For example, in:
4237 template <class T> class C { void f(C<T>); }
4239 the `C<T>' is just the same as `C'. Outside of the
4240 class, however, such a reference is an instantiation. */
4242 arglist))
4243 {
4247 {
4248 tree ctx;
4250 /* Note that we use DECL_CONTEXT, rather than
4251 CP_DECL_CONTEXT, so that the termination test is
4252 always just `ctx'. We're not interested in namespace
4253 scopes. */
4255 ctx;
4261 /* We're not in the scope of the class, so the
4262 TEMPLATE_TYPE is not the type we want after
4263 all. */
4265 }
4266 }
4274 {
4277 /* Use the move-to-front heuristic to speed up future
4278 searches. */
4285 }
4287 /* This type is a "partial instantiation" if any of the template
4288 arguments still involve template parameters. Note that we set
4289 IS_PARTIAL_INSTANTIATION for partial specializations as
4290 well. */
4296 {
4301 }
4308 /* Create the type. */
4310 {
4312 {
4315 }
4316 else
4317 /* We don't want to call start_enum for this type, since
4318 the values for the enumeration constants may involve
4319 template parameters. And, no one should be interested
4320 in the enumeration constants for such a type. */
4322 }
4323 else
4324 {
4332 /* A local class. Make sure the decl gets registered properly. */
4335 }
4337 /* If we called start_enum or pushtag above, this information
4338 will already be set up. */
4340 {
4348 }
4349 else
4357 /* Set up the template information. We have to figure out which
4358 template is the immediate parent if this is a full
4359 instantiation. */
4362 /* This case is easy; there are no member templates involved. */
4364 else
4365 {
4366 /* This is a full instantiation of a member template. Look
4367 for a partial instantiation of which this is an instance. */
4371 {
4375 /* We only want partial instantiations, here, not
4376 specializations or full instantiations. */
4381 /* Temporarily reduce by one the number of levels in the
4382 ARGLIST and in FOUND so as to avoid comparing the
4383 last set of arguments. */
4387 /* See if the arguments match. If they do, then TMPL is
4388 the partial instantiation we want. */
4391 /* Restore the argument vectors to their full size. */
4396 {
4399 }
4400 }
4403 {
4404 /* There was no partial instantiation. This happens
4405 where C<T> is a member template of A<T> and it's used
4406 in something like
4408 template <typename T> struct B { A<T>::C<int> m; };
4409 B<float>;
4411 Create the partial instantiation.
4412 */
4416 }
4417 }
4426 /* Now that the type has been registered on the instantiations
4427 list, we set up the enumerators. Because the enumeration
4428 constants may involve the enumeration type itself, we make
4429 sure to register the type first, and then create the
4430 constants. That way, doing tsubst_expr for the enumeration
4431 constants won't result in recursive calls here; we'll find
4432 the instantiation and exit above. */
4435 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4436 is set up. */
4440 {
4441 /* For backwards compatibility; code that uses
4442 -fexternal-templates expects looking up a template to
4443 instantiate it. I think DDD still relies on this.
4444 (jason 8/20/1998) */
4446 && flag_external_templates
4450 }
4451 else
4452 /* If the type makes use of template parameters, the
4453 code that generates debugging information will crash. */
4457 }
4459 }
4460 \f
4461 struct pair_fn_data
4462 {
4463 tree_fn_t fn;
4465 htab_t visited;
4466 };
4468 /* Called from for_each_template_parm via walk_tree. */
4470 static tree
4475 {
4482 /* If we have already visited this tree, there's no need to walk
4483 subtrees. Otherwise, add it to the visited table. */
4486 {
4489 }
4497 {
4501 /* Fall through. */
4513 /* Since we're not going to walk subtrees, we have to do this
4514 explicitly here. */
4518 /* Fall through. */
4521 /* Check the return type. */
4525 /* Check the parameter types. Since default arguments are not
4526 instantiated until they are needed, the TYPE_ARG_TYPES may
4527 contain expressions that involve template parameters. But,
4528 no-one should be looking at them yet. And, once they're
4529 instantiated, they don't contain template parameters, so
4530 there's no point in looking at them then, either. */
4531 {
4532 tree parm;
4539 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4540 want walk_tree walking into them itself. */
4542 }
4557 /* Fall through. */
4572 /* Record template parameters such as `T' inside `TT<T>'. */
4575 /* Fall through. */
4587 /* A template template parameter is encountered */
4592 /* Already substituted template template parameter */
4613 /* If there's no type, then this thing must be some expression
4614 involving template parameters. */
4635 /* If we do not handle this case specially, we end up walking
4636 the BINFO hierarchy, which is circular, and therefore
4637 confuses walk_tree. */
4646 }
4648 /* We didn't find any template parameters we liked. */
4650 }
4652 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4653 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4654 call FN with the parameter and the DATA.
4655 If FN returns nonzero, the iteration is terminated, and
4656 for_each_template_parm returns 1. Otherwise, the iteration
4657 continues. If FN never returns a nonzero value, the value
4658 returned by for_each_template_parm is 0. If FN is NULL, it is
4659 considered to be the function which always returns 1. */
4661 static int
4663 tree t;
4664 tree_fn_t fn;
4666 htab_t visited;
4667 {
4671 /* Set up. */
4675 /* Walk the tree. (Conceptually, we would like to walk without
4676 duplicates, but for_each_template_parm_r recursively calls
4677 for_each_template_parm, so we would need to reorganize a fair
4678 bit to use walk_tree_without_duplicates, so we keep our own
4679 visited list.) */
4682 else
4684 NULL);
4686 for_each_template_parm_r,
4690 /* Clean up. */
4695 }
4697 int
4699 tree t;
4700 {
4702 }
4706 #ifdef GATHER_STATISTICS
4708 #endif
4712 /* We're starting to instantiate D; record the template instantiation context
4713 for diagnostics and to restore it later. */
4715 int
4717 tree d;
4718 {
4722 {
4723 /* If the instantiation in question still has unbound template parms,
4724 we don't really care if we can't instantiate it, so just return.
4725 This happens with base instantiation for implicit `typename'. */
4730 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4736 }
4743 #ifdef GATHER_STATISTICS
4746 #endif
4750 }
4752 /* We're done instantiating this template; return to the instantiation
4753 context. */
4755 void
4757 {
4760 /* Restore the filename and line number stashed away when we started
4761 this instantiation. */
4769 }
4771 /* We're instantiating a deferred template; restore the template
4772 instantiation context in which the instantiation was requested, which
4773 is one step out from LEVEL. */
4775 static void
4777 tree level;
4778 {
4779 tree t;
4787 }
4789 /* Return the outermost template instantiation context, for use with
4790 -falt-external-templates. */
4792 tree
4794 {
4799 ;
4801 }
4803 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4804 vector of template arguments, as for tsubst.
4806 Returns an appropriate tsubst'd friend declaration. */
4808 static tree
4810 tree decl;
4811 tree args;
4812 {
4813 tree new_friend;
4823 /* This was a friend declared with an explicit template
4824 argument list, e.g.:
4826 friend void f<>(T);
4828 to indicate that f was a template instantiation, not a new
4829 function declaration. Now, we have to figure out what
4830 instantiation of what template. */
4831 {
4833 tree new_args;
4834 tree tmpl;
4837 /* Friend functions are looked up in the containing namespace scope.
4838 We must enter that scope, to avoid finding member functions of the
4839 current cless with same name. */
4854 }
4858 /* The NEW_FRIEND will look like an instantiation, to the
4859 compiler, but is not an instantiation from the point of view of
4860 the language. For example, we might have had:
4862 template <class T> struct S {
4863 template <class U> friend void f(T, U);
4864 };
4866 Then, in S<int>, template <class U> void f(int, U) is not an
4867 instantiation of anything. */
4870 {
4874 }
4876 /* The mangled name for the NEW_FRIEND is incorrect. The function
4877 is not a template instantiation and should not be mangled like
4878 one. Therefore, we forget the mangling here; we'll recompute it
4879 later if we need it. */
4881 {
4884 }
4887 {
4888 tree old_decl;
4889 tree new_friend_template_info;
4890 tree new_friend_result_template_info;
4891 tree ns;
4894 /* We must save some information from NEW_FRIEND before calling
4895 duplicate decls since that function will free NEW_FRIEND if
4896 possible. */
4899 {
4900 /* This declaration is a `primary' template. */
4903 new_friend_is_defn
4905 new_friend_result_template_info
4907 }
4908 else
4909 {
4912 }
4914 /* Inside pushdecl_namespace_level, we will push into the
4915 current namespace. However, the friend function should go
4916 into the namespace of the template. */
4923 {
4924 /* This new friend declaration matched an existing
4925 declaration. For example, given:
4927 template <class T> void f(T);
4928 template <class U> class C {
4929 template <class T> friend void f(T) {}
4930 };
4932 the friend declaration actually provides the definition
4933 of `f', once C has been instantiated for some type. So,
4934 old_decl will be the out-of-class template declaration,
4935 while new_friend is the in-class definition.
4937 But, if `f' was called before this point, the
4938 instantiation of `f' will have DECL_TI_ARGS corresponding
4939 to `T' but not to `U', references to which might appear
4940 in the definition of `f'. Previously, the most general
4941 template for an instantiation of `f' was the out-of-class
4942 version; now it is the in-class version. Therefore, we
4943 run through all specialization of `f', adding to their
4944 DECL_TI_ARGS appropriately. In particular, they need a
4945 new set of outer arguments, corresponding to the
4946 arguments for this class instantiation.
4948 The same situation can arise with something like this:
4950 friend void f(int);
4951 template <class T> class C {
4952 friend void f(T) {}
4953 };
4955 when `C<int>' is instantiated. Now, `f(int)' is defined
4956 in the class. */
4959 /* On the other hand, if the in-class declaration does
4960 *not* provide a definition, then we don't want to alter
4961 existing definitions. We can just leave everything
4962 alone. */
4963 ;
4964 else
4965 {
4966 /* Overwrite whatever template info was there before, if
4967 any, with the new template information pertaining to
4968 the declaration. */
4972 /* duplicate_decls will take care of this case. */
4973 ;
4974 else
4975 {
4976 tree t;
4977 tree new_friend_args;
4986 {
4992 }
4994 /* Now, since specializations are always supposed to
4995 hang off of the most general template, we must move
4996 them. */
4999 {
5004 }
5005 }
5006 }
5008 /* The information from NEW_FRIEND has been merged into OLD_DECL
5009 by duplicate_decls. */
5011 }
5012 }
5014 {
5015 /* Check to see that the declaration is really present, and,
5016 possibly obtain an improved declaration. */
5018 new_friend);
5022 }
5024 done:
5028 }
5030 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5031 template arguments, as for tsubst.
5033 Returns an appropriate tsubst'd friend type or error_mark_node on
5034 failure. */
5036 static tree
5038 tree friend_tmpl;
5039 tree args;
5040 {
5041 tree friend_type;
5042 tree tmpl;
5043 tree context;
5048 {
5051 else
5053 }
5055 /* First, we look for a class template. */
5058 /* But, if we don't find one, it might be because we're in a
5059 situation like this:
5061 template <class T>
5062 struct S {
5063 template <class U>
5064 friend struct S;
5065 };
5067 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5068 for `S<int>', not the TEMPLATE_DECL. */
5070 {
5073 }
5076 {
5077 /* The friend template has already been declared. Just
5078 check to see that the declarations match, and install any new
5079 default parameters. We must tsubst the default parameters,
5080 of course. We only need the innermost template parameters
5081 because that is all that redeclare_class_template will look
5082 at. */
5085 {
5086 tree parms;
5090 }
5093 }
5094 else
5095 {
5096 /* The friend template has not already been declared. In this
5097 case, the instantiation of the template class will cause the
5098 injection of this template into the global scope. */
5101 /* The new TMPL is not an instantiation of anything, so we
5102 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5103 the new type because that is supposed to be the corresponding
5104 template decl, i.e., TMPL. */
5109 /* Inject this template into the global scope. */
5111 }
5114 {
5117 else
5119 }
5122 }
5124 /* Returns zero if TYPE cannot be completed later due to circularity.
5125 Otherwise returns one. */
5127 static int
5129 tree type;
5130 {
5139 else
5141 }
5143 tree
5145 tree type;
5146 {
5148 tree typedecl;
5149 tree pbinfo;
5159 /* Figure out which template is being instantiated. */
5163 /* Figure out which arguments are being used to do the
5164 instantiation. */
5167 /* Determine what specialization of the original template to
5168 instantiate. */
5171 {
5176 {
5178 args))
5179 {
5182 }
5183 }
5186 }
5190 else
5193 /* If the template we're instantiating is incomplete, then clearly
5194 there's nothing we can do. */
5198 /* If we've recursively instantiated too many templates, stop. */
5202 /* Now we're really doing the instantiation. Mark the type as in
5203 the process of being defined. */
5209 {
5210 /* This TYPE is actually an instantiation of a partial
5211 specialization. We replace the innermost set of ARGS with
5212 the arguments appropriate for substitution. For example,
5213 given:
5215 template <class T> struct S {};
5216 template <class T> struct S<T*> {};
5218 and supposing that we are instantiating S<int*>, ARGS will
5219 present be {int*} but we need {int}. */
5220 tree inner_args
5222 args);
5224 /* If there were multiple levels in ARGS, replacing the
5225 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5226 want, so we make a copy first. */
5228 {
5231 }
5232 else
5234 }
5237 {
5239 {
5242 }
5243 else
5244 {
5246 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
5248 }
5249 }
5250 else
5251 {
5253 }
5286 {
5292 /* Substitute into each of the bases to determine the actual
5293 basetypes. */
5295 {
5296 tree base;
5297 tree access;
5298 tree pbase;
5303 /* Substitute to figure out the base class. */
5310 }
5312 /* The list is now in reverse order; correct that. */
5315 /* Now call xref_basetypes to set up all the base-class
5316 information. */
5318 }
5320 /* Now that our base classes are set up, enter the scope of the
5321 class, so that name lookups into base classes, etc. will work
5322 correctly. This is precisely analogous to what we do in
5323 begin_class_definition when defining an ordinary non-template
5324 class. */
5327 /* Now members are processed in the order of declaration. */
5329 {
5333 {
5335 {
5336 /* Build new CLASSTYPE_TAGS. */
5340 tree newtag;
5345 {
5347 /* Unfortunately, lookup_template_class sets
5348 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5349 instantiation (i.e., for the type of a member template
5350 class nested within a template class.) This behavior is
5351 required for maybe_process_partial_specialization to work
5352 correctly, but is not accurate in this case; the TAG is not
5353 an instantiation of anything. (The corresponding
5354 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
5357 /* Now, we call pushtag to put this NEWTAG into the scope of
5358 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5359 pushtag calling push_template_decl. We don't have to do
5360 this for enums because it will already have been done in
5361 tsubst_enum. */
5365 }
5366 }
5369 {
5370 /* Build new TYPE_METHODS. */
5376 }
5377 else
5378 {
5379 /* Build new TYPE_FIELDS. */
5382 {
5383 tree r;
5385 /* The the file and line for this declaration, to assist
5386 in error message reporting. Since we called
5387 push_tinst_level above, we don't need to restore these. */
5393 {
5394 tree init;
5399 else
5408 }
5410 {
5411 /* Determine whether R has a valid type and can be
5412 completed later. If R is invalid, then it is
5413 replaced by error_mark_node so that it will not be
5414 added to TYPE_FIELDS. */
5420 {
5423 }
5424 }
5426 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5427 such a thing will already have been added to the field
5428 list by tsubst_enum in finish_member_declaration in the
5429 CLASSTYPE_TAGS case above. */
5433 {
5436 }
5437 }
5438 }
5439 }
5440 else
5441 {
5443 {
5444 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5447 tree new_friend_type;
5454 else
5455 {
5458 /* The call to xref_tag_from_type does injection for friend
5459 classes. */
5461 new_friend_type =
5464 }
5467 /* Trick make_friend_class into realizing that the friend
5468 we're adding is a template, not an ordinary class. It's
5469 important that we use make_friend_class since it will
5470 perform some error-checking and output cross-reference
5471 information. */
5479 }
5480 else
5481 {
5482 /* Build new DECL_FRIENDLIST. */
5486 }
5487 }
5488 }
5490 /* Set the file and line number information to whatever is given for
5491 the class itself. This puts error messages involving generated
5492 implicit functions at a predictable point, and the same point
5493 that would be used for non-template classes. */
5502 /* Clear this now so repo_template_used is happy. */
5506 /* Now that the class is complete, instantiate default arguments for
5507 any member functions. We don't do this earlier because the
5508 default arguments may reference members of the class. */
5512 /* Implicitly generated member functions will not have template
5513 information; they are not instantiations, but instead are
5514 created "fresh" for each instantiation. */
5526 }
5528 static int
5531 {
5536 /* Don't care if one declares its arg const and the other doesn't -- the
5537 main variant of the arg type is all that matters. */
5542 }
5544 /* If arg is a non-type template parameter that does not depend on template
5545 arguments, fold it like we weren't in the body of a template. */
5547 static tree
5549 tree arg;
5550 {
5552 {
5553 /* Sometimes, one of the args was an expression involving a
5554 template constant parameter, like N - 1. Now that we've
5555 tsubst'd, we might have something like 2 - 1. This will
5556 confuse lookup_template_class, so we do constant folding
5557 here. We have to unset processing_template_decl, to
5558 fool build_expr_from_tree() into building an actual
5559 tree. */
5561 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5562 as simple as it's going to get, and trying to reprocess
5563 the trees will break. */
5565 {
5570 }
5573 }
5575 }
5577 /* Substitute ARGS into the vector of template arguments T. */
5579 static tree
5581 tree t;
5582 tree args;
5583 tsubst_flags_t complain;
5584 {
5591 {
5596 else
5599 NULL_TREE));
5606 }
5616 }
5618 /* Return the result of substituting ARGS into the template parameters
5619 given by PARMS. If there are m levels of ARGS and m + n levels of
5620 PARMS, then the result will contain n levels of PARMS. For
5621 example, if PARMS is `template <class T> template <class U>
5622 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5623 result will be `template <int*, double, class V>'. */
5625 static tree
5627 tree parms;
5628 tree args;
5629 tsubst_flags_t complain;
5630 {
5638 {
5639 tree new_vec =
5644 {
5653 parm_decl);
5655 }
5661 }
5664 }
5666 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5667 type T. If T is not an aggregate or enumeration type, it is
5668 handled as if by tsubst. IN_DECL is as for tsubst. If
5669 ENTERING_SCOPE is nonzero, T is the context for a template which
5670 we are presently tsubst'ing. Return the substituted value. */
5672 static tree
5674 tree t;
5675 tree args;
5676 tsubst_flags_t complain;
5677 tree in_decl;
5679 {
5684 {
5689 /* else fall through */
5693 {
5694 tree argvec;
5695 tree context;
5696 tree r;
5698 /* First, determine the context for the type we are looking
5699 up. */
5702 complain,
5704 else
5707 /* Then, figure out what arguments are appropriate for the
5708 type we are trying to find. For example, given:
5710 template <class T> struct S;
5711 template <class T, class U> void f(T, U) { S<U> su; }
5713 and supposing that we are instantiating f<int, double>,
5714 then our ARGS will be {int, double}, but, when looking up
5715 S we only want {double}. */
5717 complain);
5725 }
5726 else
5727 /* This is not a template type, so there's nothing to do. */
5732 }
5733 }
5735 /* Substitute into the default argument ARG (a default argument for
5736 FN), which has the indicated TYPE. */
5738 tree
5740 tree fn;
5741 tree type;
5742 tree arg;
5743 {
5744 /* This default argument came from a template. Instantiate the
5745 default argument here, not in tsubst. In the case of
5746 something like:
5748 template <class T>
5749 struct S {
5750 static T t();
5751 void f(T = t());
5752 };
5754 we must be careful to do name lookup in the scope of S<T>,
5755 rather than in the current class.
5757 ??? current_class_type affects a lot more than name lookup. This is
5758 very fragile. Fortunately, it will go away when we do 2-phase name
5759 binding properly. */
5761 /* FN is already the desired FUNCTION_DECL. */
5769 /* Make sure the default argument is reasonable. */
5773 }
5775 /* Substitute into all the default arguments for FN. */
5777 static void
5779 tree fn;
5780 {
5781 tree arg;
5782 tree tmpl_args;
5786 /* If this function is not yet instantiated, we certainly don't need
5787 its default arguments. */
5792 arg;
5798 }
5800 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5801 (already computed) substitution of ARGS into TREE_TYPE (T), if
5802 appropriate. Return the result of the substitution. Issue error
5803 and warning messages under control of COMPLAIN. */
5805 static tree
5807 tree t;
5808 tree args;
5809 tree type;
5810 tsubst_flags_t complain;
5811 {
5817 /* Set the filename and linenumber to improve error-reporting. */
5824 {
5826 {
5827 /* We can get here when processing a member template function
5828 of a template class. */
5830 tree spec;
5834 {
5835 /* We might already have an instance of this template.
5836 The ARGS are for the surrounding class type, so the
5837 full args contain the tsubst'd args for the context,
5838 plus the innermost args from the template decl. */
5842 tree full_args;
5845 complain);
5847 /* tsubst_template_arg_vector doesn't copy the vector if
5848 nothing changed. But, *something* should have
5849 changed. */
5854 {
5857 }
5858 }
5860 /* Make a new template decl. It will be similar to the
5861 original, but will record the current template arguments.
5862 We also create a new function declaration, which is just
5863 like the old one, but points to this new template, rather
5864 than the old one. */
5870 {
5875 }
5884 {
5890 }
5891 else
5892 {
5899 }
5905 /* The template parameters for this new template are all the
5906 template parameters for the old template, except the
5907 outermost level of parameters. */
5910 complain);
5915 /* We don't partially instantiate partial specializations. */
5919 /* Record this partial instantiation. */
5923 }
5927 {
5928 tree ctx;
5931 tree gen_tmpl;
5936 /* Nobody should be tsubst'ing into non-template functions. */
5940 {
5941 tree spec;
5943 /* Calculate the most general template of which R is a
5944 specialization, and the complete set of arguments used to
5945 specialize R. */
5947 argvec
5952 /* Check to see if we already have this specialization. */
5956 {
5959 }
5961 /* We can see more levels of arguments than parameters if
5962 there was a specialization of a member template, like
5963 this:
5965 template <class T> struct S { template <class U> void f(); }
5966 template <> template <class U> void S<int>::f(U);
5968 Here, we'll be substituting into the specialization,
5969 because that's where we can find the code we actually
5970 want to generate, but we'll have enough arguments for
5971 the most general template.
5973 We also deal with the peculiar case:
5975 template <class T> struct S {
5976 template <class U> friend void f();
5977 };
5978 template <class U> void f() {}
5979 template S<int>;
5980 template void f<double>();
5982 Here, the ARGS for the instantiation of will be {int,
5983 double}. But, we only need as many ARGS as there are
5984 levels of template parameters in CODE_PATTERN. We are
5985 careful not to get fooled into reducing the ARGS in
5986 situations like:
5988 template <class T> struct S { template <class U> void f(U); }
5989 template <class T> template <> void S<T>::f(int) {}
5991 which we can spot because the pattern will be a
5992 specialization in this case. */
5994 parms_depth =
5999 }
6000 else
6001 {
6002 /* This special case arises when we have something like this:
6004 template <class T> struct S {
6005 friend void f<int>(int, double);
6006 };
6008 Here, the DECL_TI_TEMPLATE for the friend declaration
6009 will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are
6010 being called from tsubst_friend_function, and we want
6011 only to create a new decl (R) with appropriate types so
6012 that we can call determine_specialization. */
6014 }
6017 {
6020 else
6025 }
6026 else
6027 {
6030 }
6035 /* We do NOT check for matching decls pushed separately at this
6036 point, as they may not represent instantiations of this
6037 template, and in any case are considered separate under the
6038 discrete model. */
6042 /* Clear out the mangled name and RTL for the instantiation. */
6049 /* Type-conversion operator. Reconstruct the name, in
6050 case it's the name of one of the template's parameters. */
6068 {
6073 }
6075 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6076 this in the special friend case mentioned above where
6077 GEN_TMPL is NULL. */
6079 {
6085 /* We're not supposed to instantiate default arguments
6086 until they are called, for a template. But, for a
6087 declaration like:
6089 template <class T> void f ()
6090 { extern void g(int i = T()); }
6092 we should do the substitution when the template is
6093 instantiated. We handle the member function case in
6094 instantiate_class_template since the default arguments
6095 might refer to other members of the class. */
6100 }
6102 /* Copy the list of befriending classes. */
6106 {
6110 in_decl);
6111 }
6114 {
6118 /* If this is an instantiation of a member template, clone it.
6119 If it isn't, that'll be handled by
6120 clone_constructors_and_destructors. */
6123 }
6126 }
6130 {
6140 else
6151 }
6155 {
6160 /* We don't have to set DECL_CONTEXT here; it is set by
6161 finish_member_declaration. */
6167 }
6171 {
6176 }
6182 {
6183 /* If this is the canonical decl, we don't have to mess with
6184 instantiations, and often we can't (for typename, template
6185 type parms and such). Note that TYPE_NAME is not correct for
6186 the above test if we've copied the type for a typedef. */
6189 }
6191 /* Fall through. */
6194 {
6197 tree spec;
6199 tree ctx;
6202 /* Assume this is a non-local variable. */
6207 complain,
6211 else
6212 {
6213 /* Subsequent calls to pushdecl will fill this in. */
6216 }
6218 /* Check to see if we already have this specialization. */
6220 {
6225 }
6226 else
6230 {
6233 }
6241 /* Clear out the mangled name and RTL for the instantiation. */
6245 /* Don't try to expand the initializer until someone tries to use
6246 this variable; otherwise we run into circular dependencies. */
6251 /* Even if the original location is out of scope, the newly
6252 substituted one is not. */
6254 {
6257 }
6260 {
6261 /* A static data member declaration is always marked
6262 external when it is declared in-class, even if an
6263 initializer is present. We mimic the non-template
6264 processing here. */
6270 }
6271 else
6277 /* Compute the size, alignment, etc. of R. */
6279 }
6284 }
6286 /* Restore the file and line information. */
6291 }
6293 /* Substitue into the ARG_TYPES of a function type. */
6295 static tree
6297 tree arg_types;
6298 tree args;
6299 tsubst_flags_t complain;
6300 tree in_decl;
6301 {
6302 tree remaining_arg_types;
6303 tree type;
6317 {
6319 {
6323 }
6325 }
6327 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6328 top-level qualifiers as required. */
6331 /* Note that we do not substitute into default arguments here. The
6332 standard mandates that they be instantiated only when needed,
6333 which is done in build_over_call. */
6335 remaining_arg_types);
6337 }
6339 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6340 *not* handle the exception-specification for FNTYPE, because the
6341 initial substitution of explicitly provided template parameters
6342 during argument deduction forbids substitution into the
6343 exception-specification:
6345 [temp.deduct]
6347 All references in the function type of the function template to the
6348 corresponding template parameters are replaced by the specified tem-
6349 plate argument values. If a substitution in a template parameter or
6350 in the function type of the function template results in an invalid
6351 type, type deduction fails. [Note: The equivalent substitution in
6352 exception specifications is done only when the function is instanti-
6353 ated, at which point a program is ill-formed if the substitution
6354 results in an invalid type.] */
6356 static tree
6358 tree t;
6359 tree args;
6360 tsubst_flags_t complain;
6361 tree in_decl;
6362 {
6363 tree return_type;
6364 tree arg_types;
6365 tree fntype;
6367 /* The TYPE_CONTEXT is not used for function/method types. */
6370 /* Substitute the return type. */
6375 /* Substitue the argument types. */
6381 /* Construct a new type node and return it. */
6384 else
6385 {
6388 {
6389 /* [temp.deduct]
6391 Type deduction may fail for any of the following
6392 reasons:
6394 -- Attempting to create "pointer to member of T" when T
6395 is not a class type. */
6398 r);
6400 }
6404 }
6409 }
6411 /* Substitute into the PARMS of a call-declarator. */
6413 static tree
6415 tree parms;
6416 tree args;
6417 tsubst_flags_t complain;
6418 tree in_decl;
6419 {
6420 tree new_parms;
6421 tree type;
6422 tree defarg;
6430 /* Figure out the type of this parameter. */
6433 /* Figure out the default argument as well. Note that we use
6434 tsubst_expr since the default argument is really an expression. */
6437 /* Chain this parameter on to the front of those we have already
6438 processed. We don't use hash_tree_cons because that function
6439 doesn't check TREE_PARMLIST. */
6442 /* And note that these are parameters. */
6446 }
6448 /* Take the tree structure T and replace template parameters used
6449 therein with the argument vector ARGS. IN_DECL is an associated
6450 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6451 Issue error and warning messages under control of COMPLAIN. Note
6452 that we must be relatively non-tolerant of extensions here, in
6453 order to preserve conformance; if we allow substitutions that
6454 should not be allowed, we may allow argument deductions that should
6455 not succeed, and therefore report ambiguous overload situations
6456 where there are none. In theory, we could allow the substitution,
6457 but indicate that it should have failed, and allow our caller to
6458 make sure that the right thing happens, but we don't try to do this
6459 yet.
6461 This function is used for dealing with types, decls and the like;
6462 for expressions, use tsubst_expr or tsubst_copy. */
6464 static tree
6467 tsubst_flags_t complain;
6468 tree in_decl;
6469 {
6481 else
6500 {
6527 {
6534 /* See if we can reduce this expression to something simpler. */
6540 /* When providing explicit arguments to a template
6541 function, but leaving some arguments for subsequent
6542 deduction, MAX may be template-dependent even if we're
6543 not PROCESSING_TEMPLATE_DECL. We still need to check for
6544 template parms, though; MAX won't be an INTEGER_CST for
6545 dynamic arrays, either. */
6548 {
6552 integer_one_node);
6554 }
6557 {
6558 /* Still allow an explicit array of size zero. */
6561 }
6565 {
6566 /* [temp.deduct]
6568 Type deduction may fail for any of the following
6569 reasons:
6571 Attempting to create an array with a size that is
6572 zero or negative. */
6577 }
6580 }
6586 {
6596 {
6599 }
6600 else
6601 {
6604 }
6607 {
6617 {
6619 {
6621 return cp_build_qualified_type_real
6624 }
6626 {
6627 /* We are processing a type constructed from
6628 a template template parameter */
6634 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6635 we are resolving nested-types in the signature of
6636 a member function templates.
6637 Otherwise ARG is a TEMPLATE_DECL and is the real
6638 template to be instantiated. */
6646 complain);
6647 return cp_build_qualified_type_real
6649 }
6650 else
6651 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6653 }
6654 }
6655 else
6659 /* This can happen during the attempted tsubst'ing in
6660 unify. This means that we don't yet have any information
6661 about the template parameter in question. */
6664 /* If we get here, we must have been looking at a parm for a
6665 more deeply nested template. Make a new version of this
6666 template parameter, but with a lower level. */
6668 {
6673 {
6675 r = cp_build_qualified_type_real
6679 }
6680 else
6681 {
6692 {
6700 }
6701 }
6710 }
6713 }
6716 {
6724 {
6728 }
6731 {
6735 }
6738 {
6742 }
6748 {
6751 }
6752 else
6755 }
6758 {
6759 /* A binfo node. We always need to make a copy, of the node
6760 itself and of its BINFO_BASETYPES. */
6764 /* Make sure type isn't a typedef copy. */
6769 {
6774 }
6776 }
6778 /* Otherwise, a vector of template arguments. */
6783 {
6792 /* [temp.deduct]
6794 Type deduction may fail for any of the following
6795 reasons:
6797 -- Attempting to create a pointer to reference type.
6798 -- Attempting to create a reference to a reference type or
6799 a reference to void. */
6802 {
6806 /* We keep track of the last time we issued this error
6807 message to avoid spewing a ton of messages during a
6808 single bad template instantiation. */
6811 {
6814 else
6817 type);
6820 }
6823 }
6825 {
6829 }
6830 else
6835 /* Will this ever be needed for TYPE_..._TO values? */
6839 }
6841 {
6844 {
6845 /* [temp.deduct]
6847 Type deduction may fail for any of the following
6848 reasons:
6850 -- Attempting to create "pointer to member of T" when T
6851 is not a class type. */
6855 }
6857 {
6862 }
6865 /* This is really a method type. The cv qualifiers of the
6866 this pointer should _not_ be determined by the cv
6867 qualifiers of the class type. They should be held
6868 somewhere in the FUNCTION_TYPE, but we don't do that at
6869 the moment. Consider
6870 typedef void (Func) () const;
6872 template <typename T1> void Foo (Func T1::*);
6874 */
6878 else
6880 }
6883 {
6884 tree fntype;
6885 tree raises;
6891 /* Substitue the exception specification. */
6894 {
6899 else
6901 {
6908 }
6910 }
6912 }
6914 {
6919 /* As an optimization, we avoid regenerating the array type if
6920 it will obviously be the same as T. */
6924 /* These checks should match the ones in grokdeclarator.
6926 [temp.deduct]
6928 The deduction may fail for any of the following reasons:
6930 -- Attempting to create an array with an element type that
6931 is void, a function type, or a reference type. */
6935 {
6939 }
6943 }
6947 {
6955 }
6959 {
6965 }
6968 {
6978 {
6981 ctx);
6983 }
6985 {
6986 /* Normally, make_typename_type does not require that the CTX
6987 have complete type in order to allow things like:
6989 template <class T> struct S { typename S<T>::X Y; };
6991 But, such constructs have already been resolved by this
6992 point, so here CTX really should have complete type, unless
6993 it's a partial instantiation. */
6996 {
7000 }
7001 }
7008 {
7011 }
7013 return cp_build_qualified_type_real
7015 }
7018 {
7027 }
7030 {
7035 }
7038 {
7043 }
7046 {
7053 }
7056 {
7058 tree e2 = (tsubst_call_declarator_parms
7068 }
7071 {
7078 }
7081 {
7087 }
7093 }
7094 }
7096 /* Like tsubst, but deals with expressions. This function just replaces
7097 template parms; to finish processing the resultant expression, use
7098 tsubst_expr. */
7100 static tree
7103 tsubst_flags_t complain;
7104 tree in_decl;
7105 {
7107 tree r;
7115 {
7122 {
7123 tree enum_type;
7124 tree v;
7129 /* This is a global enumeration constant. */
7132 /* Unfortunately, we cannot just call lookup_name here.
7133 Consider:
7135 template <int I> int f() {
7136 enum E { a = I };
7137 struct S { void g() { E e = a; } };
7138 };
7140 When we instantiate f<7>::S::g(), say, lookup_name is not
7141 clever enough to find f<7>::a. */
7142 enum_type
7146 /* Not yet available. */
7156 /* We didn't find the name. That should never happen; if
7157 name-lookup found it during preliminary parsing, we
7158 should find it again here during instantiation. */
7160 }
7165 {
7166 tree ctx;
7172 }
7184 {
7185 tree name;
7186 tree qualifying_scope;
7187 tree fns;
7191 /* A baselink indicates a function from a base class. The
7192 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7193 non-dependent types; otherwise, the lookup could not have
7194 succeeded. However, they may indicate bases of the template
7195 class, rather than the instantiated class.
7197 In addition, lookups that were not ambiguous before may be
7198 ambiguous now. Therefore, we perform the lookup again. */
7202 {
7206 }
7213 template_args);
7215 qualifying_scope,
7216 current_class_type);
7217 }
7225 else
7229 {
7230 /* We must tsubst into a LOOKUP_EXPR in case the names to
7231 which it refers is a conversion operator; in that case the
7232 name will change. We avoid making unnecessary copies,
7233 however. */
7238 {
7242 }
7245 }
7253 return build1
7270 return build1
7275 {
7276 tree object;
7277 tree name;
7282 {
7286 }
7289 {
7297 }
7298 else
7301 }
7342 return build_nt
7351 in_decl),
7352 NULL_TREE);
7355 return build_nt
7360 NULL_TREE);
7363 /* This processing should really occur in tsubst_expr. However,
7364 tsubst_expr does not recurse into expressions, since it
7365 assumes that there aren't any statements inside them. So, we
7366 need to expand the STMT_EXPR here. */
7368 {
7372 }
7379 {
7380 r = build_nt
7385 }
7388 {
7389 r = build_nt
7395 }
7398 {
7399 r = build_nt
7405 }
7408 {
7409 /* Substituted template arguments */
7411 in_decl);
7414 {
7415 tree chain;
7418 }
7420 {
7425 }
7427 return lookup_template_function
7429 }
7432 {
7452 }
7476 {
7479 }
7480 else
7484 {
7485 r = build
7491 }
7495 in_decl),
7500 }
7501 }
7503 /* Like tsubst_copy for expressions, etc. but also does semantic
7504 processing. */
7506 static tree
7509 tsubst_flags_t complain;
7510 tree in_decl;
7511 {
7524 {
7550 {
7551 tree decl;
7552 tree init;
7559 {
7565 name,
7568 }
7569 else
7570 {
7574 {
7577 /* By marking the declaration as instantiated, we avoid
7578 trying to instantiate it. Since instantiate_decl can't
7579 handle local variables, and since we've already done
7580 all that needs to be done, that's the right thing to
7581 do. */
7586 /* Anonymous aggregates are a special case. */
7588 else
7589 {
7592 {
7593 /* For __PRETTY_FUNCTION__ we have to adjust the
7594 initializer. */
7599 }
7600 else
7603 }
7604 }
7605 }
7607 /* A DECL_STMT can also be used as an expression, in the condition
7608 clause of an if/for/while construct. If we aren't followed by
7609 another statement, return our decl. */
7612 }
7616 {
7624 stmt);
7629 }
7633 {
7638 stmt);
7641 }
7645 {
7652 stmt);
7653 }
7657 {
7662 stmt);
7665 {
7668 }
7671 {
7675 }
7678 }
7682 {
7686 else
7693 else
7695 }
7709 {
7710 tree val;
7718 }
7725 in_decl));
7742 /* Computed goto's must be tsubst'd into. On the other hand,
7743 non-computed gotos must not be; the identifier in question
7744 will have no binding. */
7746 else
7753 tmp = finish_asm_stmt
7765 {
7771 stmt);
7772 }
7773 else
7774 {
7777 else
7784 else
7790 else
7792 }
7796 {
7797 tree decl;
7802 {
7805 /* Prevent instantiate_decl from trying to instantiate
7806 this variable. We've already done all that needs to be
7807 done. */
7809 }
7810 else
7815 }
7825 }
7828 }
7830 /* Like tsubst but deals with expressions and performs semantic
7831 analysis. */
7833 static tree
7836 tsubst_flags_t complain;
7837 tree in_decl;
7838 {
7843 {
7846 {
7849 NULL_TREE);
7850 }
7851 else
7855 {
7857 {
7858 tree token
7861 }
7862 else
7863 {
7864 t = do_identifier
7865 (tsubst_copy
7867 NULL_TREE);
7871 }
7872 }
7875 {
7876 tree object;
7877 tree template
7881 {
7884 }
7885 else
7895 else
7897 }
7900 return build_x_indirect_ref
7905 return build_functional_cast
7910 return build_reinterpret_cast
7915 return build_const_cast
7920 return build_dynamic_cast
7925 return build_static_cast
7935 else
7936 return build_x_unary_op
7939 in_decl));
7945 else
7946 return build_x_unary_op
7949 in_decl));
7954 return build_x_unary_op
7965 else
7966 return build_x_unary_op
7969 in_decl));
8002 return build_x_binary_op
8008 return build_m_component_ref
8013 return build_offset_ref
8018 {
8021 /* new-type-id */
8022 return build_nt
8025 in_decl));
8027 return grok_array_decl
8029 in_decl),
8031 in_decl));
8032 }
8036 {
8037 tree r =
8042 else
8044 }
8047 return build_x_modify_expr
8053 return build_x_arrow
8057 return build_new
8064 return delete_sanity
8071 {
8074 return build_x_compound_expr
8076 in_decl));
8077 else
8079 }
8082 {
8083 tree method
8087 {
8095 return build_scoped_method_call
8096 (tsubst_copy_and_build
8099 name,
8100 tsubst_copy_and_build
8102 }
8103 else
8104 {
8105 /* We can get a TEMPLATE_ID_EXPR here on code like:
8107 x->f<2>();
8109 so we must resolve that. However, we can also get things
8110 like a BIT_NOT_EXPR here, when referring to a destructor,
8111 and things like that are not correctly resolved by this
8112 function so just use it when we really need it. */
8114 method = lookup_template_function
8118 return build_method_call
8119 (tsubst_copy_and_build
8121 method,
8122 tsubst_copy_and_build
8125 }
8126 }
8129 {
8139 {
8147 name);
8150 }
8151 else
8152 {
8154 tree id;
8160 && (!current_class_type
8162 {
8163 /* Do Koenig lookup if there are no class members. */
8165 }
8175 copy_args);
8179 }
8180 }
8183 return build_x_conditional_expr
8189 return finish_pseudo_destructor_expr
8195 {
8215 }
8218 {
8219 tree object =
8221 tree member =
8225 {
8228 NULL_TREE,
8233 object,
8235 }
8238 {
8239 tree tmpl;
8240 tree args;
8242 /* Lookup the template functions now that we know what the
8243 scope is. */
8247 tmpl,
8253 args);
8254 else
8255 {
8259 }
8260 }
8263 }
8266 return build_throw
8270 {
8271 tree r;
8272 tree elts;
8276 /* digest_init will do the wrong thing if we let it. */
8281 /* We do not want to process the purpose of aggregate
8282 initializers as they are identifier nodes which will be
8283 looked up by digest_init. */
8286 elts;
8288 {
8293 purpose
8297 }
8305 }
8308 {
8309 tree operand_0
8311 in_decl);
8316 }
8325 return build_x_va_arg
8326 (tsubst_copy_and_build
8332 }
8333 }
8335 /* Instantiate the indicated variable or function template TMPL with
8336 the template arguments in TARG_PTR. */
8338 tree
8341 {
8342 tree fndecl;
8343 tree gen_tmpl;
8344 tree spec;
8346 tree inner_args;
8353 /* If this function is a clone, handle it specially. */
8355 {
8357 tree clone;
8359 /* Look for the clone. */
8365 /* We should always have found the clone by now. */
8368 }
8370 /* Check to see if we already have this specialization. */
8377 {
8378 /* The TMPL is a partial instantiation. To get a full set of
8379 arguments we must add the arguments used to perform the
8380 partial instantiation. */
8382 targ_ptr);
8384 /* Check to see if we already have this specialization. */
8388 }
8394 {
8397 {
8400 {
8404 }
8405 }
8406 }
8408 /* Make sure that we can see identifiers, and compute access
8409 correctly. The desired FUNCTION_DECL for FNDECL may or may not be
8410 created earlier. Let push_access_scope_real figure that out. */
8411 push_access_scope_real
8415 /* substitute template parameters */
8421 /* The DECL_TI_TEMPLATE should always be the immediate parent
8422 template, not the most general template. */
8428 /* If we've just instantiated the main entry point for a function,
8429 instantiate all the alternate entry points as well. We do this
8430 by cloning the instantiation of the main entry point, not by
8431 instantiating the template clones. */
8436 }
8438 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8439 arguments that are being used when calling it. TARGS is a vector
8440 into which the deduced template arguments are placed.
8442 Return zero for success, 2 for an incomplete match that doesn't resolve
8443 all the types, and 1 for complete failure. An error message will be
8444 printed only for an incomplete match.
8446 If FN is a conversion operator, or we are trying to produce a specific
8447 specialization, RETURN_TYPE is the return type desired.
8449 The EXPLICIT_TARGS are explicit template arguments provided via a
8450 template-id.
8452 The parameter STRICT is one of:
8454 DEDUCE_CALL:
8455 We are deducing arguments for a function call, as in
8456 [temp.deduct.call].
8458 DEDUCE_CONV:
8459 We are deducing arguments for a conversion function, as in
8460 [temp.deduct.conv].
8462 DEDUCE_EXACT:
8463 We are deducing arguments when doing an explicit instantiation
8464 as in [temp.explicit], when determining an explicit specialization
8465 as in [temp.expl.spec], or when taking the address of a function
8466 template, as in [temp.deduct.funcaddr].
8468 DEDUCE_ORDER:
8469 We are deducing arguments when calculating the partial
8470 ordering between specializations of function or class
8471 templates, as in [temp.func.order] and [temp.class.order].
8473 LEN is the number of parms to consider before returning success, or -1
8474 for all. This is used in partial ordering to avoid comparing parms for
8475 which no actual argument was passed, since they are not considered in
8476 overload resolution (and are explicitly excluded from consideration in
8477 partial ordering in [temp.func.order]/6). */
8479 int
8483 unification_kind_t strict;
8485 {
8486 tree parms;
8487 tree fntype;
8494 {
8495 /* [temp.deduct]
8497 The specified template arguments must match the template
8498 parameters in kind (i.e., type, nontype, template), and there
8499 must not be more arguments than there are parameters;
8500 otherwise type deduction fails.
8502 Nontype arguments must match the types of the corresponding
8503 nontype template parameters, or must be convertible to the
8504 types of the corresponding nontype parameters as specified in
8505 _temp.arg.nontype_, otherwise type deduction fails.
8507 All references in the function type of the function template
8508 to the corresponding template parameters are replaced by the
8509 specified template argument values. If a substitution in a
8510 template parameter or in the function type of the function
8511 template results in an invalid type, type deduction fails. */
8513 tree converted_args;
8515 converted_args
8526 /* Place the explicitly specified arguments in TARGS. */
8529 }
8532 /* Never do unification on the 'this' parameter. */
8537 {
8538 /* We've been given a return type to match, prepend it. */
8543 }
8545 /* We allow incomplete unification without an error message here
8546 because the standard doesn't seem to explicitly prohibit it. Our
8547 callers must be ready to deal with unification failures in any
8548 event. */
8554 /* All is well so far. Now, check:
8556 [temp.deduct]
8558 When all template arguments have been deduced, all uses of
8559 template parameters in nondeduced contexts are replaced with
8560 the corresponding deduced argument values. If the
8561 substitution results in an invalid type, as described above,
8562 type deduction fails. */
8568 }
8570 /* Adjust types before performing type deduction, as described in
8571 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8572 sections are symmetric. PARM is the type of a function parameter
8573 or the return type of the conversion function. ARG is the type of
8574 the argument passed to the call, or the type of the value
8575 initialized with the result of the conversion function. */
8577 static int
8579 unification_kind_t strict;
8582 {
8586 {
8591 {
8592 /* Swap PARM and ARG throughout the remainder of this
8593 function; the handling is precisely symmetric since PARM
8594 will initialize ARG rather than vice versa. */
8599 }
8602 /* There is nothing to do in this case. */
8606 /* DR 214. [temp.func.order] is underspecified, and leads to no
8607 ordering between things like `T *' and `T const &' for `U *'.
8608 The former has T=U and the latter T=U*. The former looks more
8609 specialized and John Spicer considers it well-formed (the EDG
8610 compiler accepts it).
8612 John also confirms that deduction should proceed as in a function
8613 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8614 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8615 to an actual call can have such a type.
8617 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8618 If only ARG is a REFERENCE_TYPE, we look through that and then
8619 proceed as with DEDUCE_CALL (which could further convert it). */
8621 {
8625 }
8629 }
8632 {
8633 /* [temp.deduct.call]
8635 If P is not a reference type:
8637 --If A is an array type, the pointer type produced by the
8638 array-to-pointer standard conversion (_conv.array_) is
8639 used in place of A for type deduction; otherwise,
8641 --If A is a function type, the pointer type produced by
8642 the function-to-pointer standard conversion
8643 (_conv.func_) is used in place of A for type deduction;
8644 otherwise,
8646 --If A is a cv-qualified type, the top level
8647 cv-qualifiers of A's type are ignored for type
8648 deduction. */
8653 else
8655 }
8657 /* [temp.deduct.call]
8659 If P is a cv-qualified type, the top level cv-qualifiers
8660 of P's type are ignored for type deduction. If P is a
8661 reference type, the type referred to by P is used for
8662 type deduction. */
8665 {
8668 }
8670 }
8672 /* Most parms like fn_type_unification.
8674 If SUBR is 1, we're being called recursively (to unify the
8675 arguments of a function or method parameter of a function
8676 template). */
8678 static int
8683 unification_kind_t strict;
8685 {
8697 /* ARGS could be NULL. */
8703 {
8723 }
8728 again:
8735 && args
8737 {
8746 /* We can't deduce anything from this, but we might get all the
8747 template args from other function args. */
8750 /* Conversions will be performed on a function argument that
8751 corresponds with a function parameter that contains only
8752 non-deducible template parameters and explicitly specified
8753 template parameters. */
8755 {
8756 tree type;
8760 else
8761 {
8764 }
8767 {
8770 }
8771 else
8772 /* It might work; we shouldn't check now, because we might
8773 get into infinite recursion. Overload resolution will
8774 handle it. */
8778 }
8781 {
8784 {
8785 /* [temp.deduct.type] A template-argument can be deduced from
8786 a pointer to function or pointer to member function
8787 argument if the set of overloaded functions does not
8788 contain function templates and at most one of a set of
8789 overloaded functions provides a unique match. */
8796 }
8798 }
8800 {
8808 }
8810 /* Are we done with the interesting parms? */
8813 }
8814 /* Fail if we've reached the end of the parm list, and more args
8815 are present, and the parm list isn't variadic. */
8818 /* Fail if parms are left and they don't have default values. */
8824 done:
8828 {
8831 /* If this is an undeduced nontype parameter that depends on
8832 a type parameter, try another pass; its type may have been
8833 deduced from a later argument than the one from which
8834 this parameter can be deduced. */
8843 }
8845 }
8847 /* Subroutine of type_unification_real. Args are like the variables at the
8848 call site. ARG is an overloaded function (or template-id); we try
8849 deducing template args from each of the overloads, and if only one
8850 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
8852 static int
8854 sub_strict)
8856 unification_kind_t strict;
8858 {
8866 /* Handle `&x' where `x' is some static or non-static member
8867 function name. */
8873 /* Strip baselink information. */
8878 {
8879 /* If we got some explicit template args, we need to plug them into
8880 the affected templates before we try to unify, in case the
8881 explicit args will completely resolve the templates in question. */
8887 {
8895 expl_subargs);
8897 {
8903 }
8904 }
8905 }
8908 {
8910 {
8915 type,
8917 }
8918 }
8919 else
8922 /* [temp.deduct.type] A template-argument can be deduced from a pointer
8923 to function or pointer to member function argument if the set of
8924 overloaded functions does not contain function templates and at most
8925 one of a set of overloaded functions provides a unique match.
8927 So if we found multiple possibilities, we return success but don't
8928 deduce anything. */
8931 {
8936 }
8941 }
8943 /* Subroutine of resolve_overloaded_unification; does deduction for a single
8944 overload. Fills TARGS with any deduced arguments, or error_mark_node if
8945 different overloads deduce different arguments for a given parm.
8946 Returns 1 on success. */
8948 static int
8950 sub_strict)
8952 unification_kind_t strict;
8954 {
8956 tree tempargs;
8959 /* [temp.deduct.type] A template-argument can be deduced from a pointer
8960 to function or pointer to member function argument if the set of
8961 overloaded functions does not contain function templates and at most
8962 one of a set of overloaded functions provides a unique match.
8964 So if this is a template, just return success. */
8971 /* We don't copy orig_targs for this because if we have already deduced
8972 some template args from previous args, unify would complain when we
8973 try to deduce a template parameter for the same argument, even though
8974 there isn't really a conflict. */
8981 /* First make sure we didn't deduce anything that conflicts with
8982 explicitly specified args. */
8984 {
8991 {
8992 /* Since we're unifying against ourselves, we will fill in template
8993 args used in the function parm list with our own template parms.
8994 Discard them. */
8997 }
9000 }
9003 {
9008 }
9011 }
9013 /* Verify that nondeduce template argument agrees with the type
9014 obtained from argument deduction. Return nonzero if the
9015 verification fails.
9017 For example:
9019 struct A { typedef int X; };
9020 template <class T, class U> struct C {};
9021 template <class T> struct C<T, typename T::X> {};
9023 Then with the instantiation `C<A, int>', we can deduce that
9024 `T' is `A' but unify () does not check whether `typename T::X'
9025 is `int'. This function ensure that they agree.
9027 TARGS, PARMS are the same as the arguments of unify.
9028 ARGS contains template arguments from all levels. */
9030 static int
9033 {
9040 }
9042 /* PARM is a template class (perhaps with unbound template
9043 parameters). ARG is a fully instantiated type. If ARG can be
9044 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9045 TARGS are as for unify. */
9047 static tree
9049 tree tparms;
9050 tree targs;
9051 tree parm;
9052 tree arg;
9053 {
9054 tree copy_of_targs;
9060 /* We need to make a new template argument vector for the call to
9061 unify. If we used TARGS, we'd clutter it up with the result of
9062 the attempted unification, even if this class didn't work out.
9063 We also don't want to commit ourselves to all the unifications
9064 we've already done, since unification is supposed to be done on
9065 an argument-by-argument basis. In other words, consider the
9066 following pathological case:
9068 template <int I, int J, int K>
9069 struct S {};
9071 template <int I, int J>
9072 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9074 template <int I, int J, int K>
9075 void f(S<I, J, K>, S<I, I, I>);
9077 void g() {
9078 S<0, 0, 0> s0;
9079 S<0, 1, 2> s2;
9081 f(s0, s2);
9082 }
9084 Now, by the time we consider the unification involving `s2', we
9085 already know that we must have `f<0, 0, 0>'. But, even though
9086 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9087 because there are two ways to unify base classes of S<0, 1, 2>
9088 with S<I, I, I>. If we kept the already deduced knowledge, we
9089 would reject the possibility I=1. */
9092 /* If unification failed, we're done. */
9098 }
9100 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9101 have already discovered to be satisfactory. ARG_BINFO is the binfo
9102 for the base class of ARG that we are currently examining. */
9104 static tree
9107 tree tparms;
9108 tree targs;
9109 tree arg_binfo;
9110 tree rval;
9111 tree parm;
9113 {
9114 tree binfos;
9119 {
9123 /* If there is more than one satisfactory baseclass, then:
9125 [temp.deduct.call]
9127 If they yield more than one possible deduced A, the type
9128 deduction fails.
9130 applies. */
9135 }
9140 /* Process base types. */
9142 {
9146 /* Skip this base, if we've already seen it. */
9150 this_virtual =
9153 /* When searching for a non-virtual, we cannot mark virtually
9154 found binfos. */
9159 parm,
9160 base_binfo,
9161 rval,
9164 /* If we discovered more than one matching base class, we can
9165 stop now. */
9168 }
9171 }
9173 /* Given a template type PARM and a class type ARG, find the unique
9174 base type in ARG that is an instance of PARM. We do not examine
9175 ARG itself; only its base-classes. If there is no appropriate base
9176 class, return NULL_TREE. If there is more than one, return
9177 error_mark_node. PARM may be the type of a partial specialization,
9178 as well as a plain template type. Used by unify. */
9180 static tree
9182 tree tparms;
9183 tree targs;
9184 tree parm;
9185 tree arg;
9186 {
9187 tree rval;
9188 tree arg_binfo;
9195 NULL_TREE,
9196 GTB_IGNORE_TYPE);
9198 /* Since get_template_base_recursive marks the bases classes, we
9199 must unmark them here. */
9203 }
9205 /* Returns the level of DECL, which declares a template parameter. */
9207 static int
9209 tree decl;
9210 {
9212 {
9223 }
9224 }
9226 /* Decide whether ARG can be unified with PARM, considering only the
9227 cv-qualifiers of each type, given STRICT as documented for unify.
9228 Returns nonzero iff the unification is OK on that basis.*/
9230 static int
9233 tree arg;
9234 tree parm;
9235 {
9240 {
9241 /* If the cvr quals of parm will not unify with ARG, they'll be
9242 ignored in instantiation, so we have to do the same here. */
9248 }
9259 }
9261 /* Takes parameters as for type_unification. Returns 0 if the
9262 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9263 bitwise or of the following flags:
9265 UNIFY_ALLOW_NONE:
9266 Require an exact match between PARM and ARG.
9267 UNIFY_ALLOW_MORE_CV_QUAL:
9268 Allow the deduced ARG to be more cv-qualified (by qualification
9269 conversion) than ARG.
9270 UNIFY_ALLOW_LESS_CV_QUAL:
9271 Allow the deduced ARG to be less cv-qualified than ARG.
9272 UNIFY_ALLOW_DERIVED:
9273 Allow the deduced ARG to be a template base class of ARG,
9274 or a pointer to a template base class of the type pointed to by
9275 ARG.
9276 UNIFY_ALLOW_INTEGER:
9277 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9278 case for more information.
9279 UNIFY_ALLOW_OUTER_LEVEL:
9280 This is the outermost level of a deduction. Used to determine validity
9281 of qualification conversions. A valid qualification conversion must
9282 have const qualified pointers leading up to the inner type which
9283 requires additional CV quals, except at the outer level, where const
9284 is not required [conv.qual]. It would be normal to set this flag in
9285 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9286 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9287 This is the outermost level of a deduction, and PARM can be more CV
9288 qualified at this point.
9289 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9290 This is the outermost level of a deduction, and PARM can be less CV
9291 qualified at this point.
9292 UNIFY_ALLOW_MAX_CORRECTION:
9293 This is an INTEGER_TYPE's maximum value. Used if the range may
9294 have been derived from a size specification, such as an array size.
9295 If the size was given by a nontype template parameter N, the maximum
9296 value will have the form N-1. The flag says that we can (and indeed
9297 must) unify N with (ARG + 1), an exception to the normal rules on
9298 folding PARM. */
9300 static int
9304 {
9306 tree targ;
9307 tree tparm;
9310 /* I don't think this will do the right thing with respect to types.
9311 But the only case I've seen it in so far has been array bounds, where
9312 signedness is the only information lost, and I think that will be
9313 okay. */
9320 /* We can't deduce anything from this, but we might get all the
9321 template args from other function args. */
9324 /* If PARM uses template parameters, then we can't bail out here,
9325 even if ARG == PARM, since we won't record unifications for the
9326 template parameters. We might need them if we're trying to
9327 figure out which of two things is more specialized. */
9331 /* Immediately reject some pairs that won't unify because of
9332 cv-qualification mismatches. */
9335 /* It is the elements of the array which hold the cv quals of an array
9336 type, and the elements might be template type parms. We'll check
9337 when we recurse. */
9339 /* We check the cv-qualifiers when unifying with template type
9340 parameters below. We want to allow ARG `const T' to unify with
9341 PARM `T' for example, when computing which of two templates
9342 is more specialized, for example. */
9357 {
9361 /* In a type which contains a nested-name-specifier, template
9362 argument values cannot be deduced for template parameters used
9363 within the nested-name-specifier. */
9373 /* The PARM is not one we're trying to unify. Just check
9374 to see if it matches ARG. */
9381 /* Check for mixed types and values. */
9389 {
9390 /* ARG must be constructed from a template class or a template
9391 template parameter. */
9396 {
9400 tree argtmplvec
9404 /* The parameter and argument roles have to be switched here
9405 in order to handle default arguments properly. For example,
9406 template<template <class> class TT> void f(TT<int>)
9407 should be able to accept vector<int> which comes from
9408 template <class T, class Allocator = allocator>
9409 class vector. */
9415 /* Deduce arguments T, i from TT<T> or TT<i>.
9416 We check each element of PARMVEC and ARGVEC individually
9417 rather than the whole TREE_VEC since they can have
9418 different number of elements. */
9421 {
9426 UNIFY_ALLOW_NONE))
9428 }
9429 }
9432 /* Fall through to deduce template name. */
9433 }
9437 {
9438 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9440 /* Simple cases: Value already set, does match or doesn't. */
9445 }
9446 else
9447 {
9448 /* If ARG is an offset type, we're trying to unify '*T' with
9449 'U C::*', which is ill-formed. See the comment in the
9450 POINTER_TYPE case about this ugliness. */
9454 /* If PARM is `const T' and ARG is only `int', we don't have
9455 a match unless we are allowing additional qualification.
9456 If ARG is `const int' and PARM is just `T' that's OK;
9457 that binds `const int' to `T'. */
9462 /* Consider the case where ARG is `const volatile int' and
9463 PARM is `const T'. Then, T should be `volatile int'. */
9464 arg = cp_build_qualified_type_real
9469 /* Simple cases: Value already set, does match or doesn't. */
9475 /* Make sure that ARG is not a variable-sized array. (Note
9476 that were talking about variable-sized arrays (like
9477 `int[n]'), rather than arrays of unknown size (like
9478 `int[]').) We'll get very confused by such a type since
9479 the bound of the array will not be computable in an
9480 instantiation. Besides, such types are not allowed in
9481 ISO C++, so we can do as we please here. */
9484 }
9494 /* The PARM is not one we're trying to unify. Just check
9495 to see if it matches ARG. */
9503 {
9509 else
9511 }
9513 /* [temp.deduct.type] If, in the declaration of a function template
9514 with a non-type template-parameter, the non-type
9515 template-parameter is used in an expression in the function
9516 parameter-list and, if the corresponding template-argument is
9517 deduced, the template-argument type shall match the type of the
9518 template-parameter exactly, except that a template-argument
9519 deduced from an array bound may be of any integral type.
9520 The non-type parameter might use already deduced type parameters. */
9523 /* Template-parameter dependent expression. Just accept it for now.
9524 It will later be processed in convert_template_argument. */
9525 ;
9533 /* We haven't deduced the type of this parameter yet. Try again
9534 later. */
9536 else
9543 {
9547 /* [temp.deduct.call]
9549 A can be another pointer or pointer to member type that can
9550 be converted to the deduced A via a qualification
9551 conversion (_conv.qual_).
9553 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9554 This will allow for additional cv-qualification of the
9555 pointed-to types if appropriate. */
9558 /* The derived-to-base conversion only persists through one
9559 level of pointers. */
9564 {
9565 /* Avoid getting confused about cv-quals; don't recurse here.
9566 Pointers to members should really be just OFFSET_TYPE, not
9567 this two-level nonsense... */
9572 }
9576 }
9608 {
9618 }
9619 /* We have already checked cv-qualification at the top of the
9620 function. */
9624 /* As far as unification is concerned, this wins. Later checks
9625 will invalidate it if necessary. */
9628 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9629 /* Type INTEGER_CST can come from ordinary constant template args. */
9639 {
9648 UNIFY_ALLOW_NONE))
9651 }
9659 {
9666 strict);
9667 }
9670 {
9674 {
9675 /* First, we try to unify the PARM and ARG directly. */
9680 {
9681 /* Fallback to the special case allowed in
9682 [temp.deduct.call]:
9684 If P is a class, and P has the form
9685 template-id, then A can be a derived class of
9686 the deduced A. Likewise, if P is a pointer to
9687 a class of the form template-id, A can be a
9688 pointer to a derived class pointed to by the
9689 deduced A. */
9695 }
9696 }
9700 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9701 Then, we should unify `int' and `U'. */
9703 else
9704 /* There's no chance of unification succeeding. */
9709 }
9727 offset:
9734 strict);
9744 /* Matched cases are handled by the ARG == PARM test above. */
9750 {
9751 /* We handle this case specially, since it comes up with
9752 arrays. In particular, something like:
9754 template <int N> void f(int (&x)[N]);
9756 Here, we are trying to unify the range type, which
9757 looks like [0 ... (N - 1)]. */
9765 }
9766 /* else fall through */
9770 {
9772 /* We're looking at an expression. This can happen with
9773 something like:
9775 template <int I>
9776 void foo(S<I>, S<I + 2>);
9778 This is a "nondeduced context":
9780 [deduct.type]
9782 The nondeduced contexts are:
9784 --A type that is a template-id in which one or more of
9785 the template-arguments is an expression that references
9786 a template-parameter.
9788 In these cases, we assume deduction succeeded, but don't
9789 actually infer any unifications. */
9794 else
9796 }
9797 else
9802 }
9803 }
9804 \f
9805 /* Called if RESULT is explicitly instantiated, or is a member of an
9806 explicitly instantiated class, or if using -frepo and the
9807 instantiation of RESULT has been assigned to this file. */
9809 void
9811 tree result;
9813 {
9815 /* The TREE_PUBLIC flag for function declarations will have been
9816 set correctly by tsubst. */
9819 /* We used to set this unconditionally; we moved that to
9820 do_decl_instantiation so it wouldn't get set on members of
9821 explicit class template instantiations. But we still need to set
9822 it here for the 'extern template' case in order to suppress
9823 implicit instantiations. */
9828 {
9832 /* Always make artificials weak. */
9835 /* For WIN32 we also want to put explicit instantiations in
9836 linkonce sections. */
9839 }
9842 }
9844 /* Given two function templates PAT1 and PAT2, return:
9846 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
9848 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
9849 -1 if PAT2 is more specialized than PAT1.
9850 0 if neither is more specialized.
9852 LEN is passed through to fn_type_unification. */
9854 int
9859 {
9860 tree targs;
9874 }
9876 /* Given two class template specialization list nodes PAT1 and PAT2, return:
9878 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
9879 -1 if PAT2 is more specialized than PAT1.
9880 0 if neither is more specialized. */
9882 int
9885 {
9886 tree targs;
9900 }
9902 /* Return the template arguments that will produce the function signature
9903 DECL from the function template FN, with the explicit template
9904 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
9905 also match. Return NULL_TREE if no satisfactory arguments could be
9906 found. DEDUCE and LEN are passed through to fn_type_unification. */
9908 static tree
9912 {
9915 tree decl_type;
9916 tree decl_arg_types;
9919 /* Substitute the explicit template arguments into the type of DECL.
9920 The call to fn_type_unification will handle substitution into the
9921 FN. */
9924 {
9925 tree tmpl;
9926 tree converted_args;
9930 else
9931 /* We can get here for some invalid specializations. */
9934 converted_args
9944 }
9947 /* Never do unification on the 'this' parameter. */
9952 decl_arg_types,
9961 }
9963 /* For most uses, we want to check the return type. */
9965 tree
9968 {
9970 }
9972 /* But for resolve_overloaded_unification, we only care about the parameter
9973 types. */
9975 static tree
9978 {
9980 }
9982 /* Return the innermost template arguments that, when applied to a
9983 template specialization whose innermost template parameters are
9984 TPARMS, and whose specialization arguments are PARMS, yield the
9985 ARGS.
9987 For example, suppose we have:
9989 template <class T, class U> struct S {};
9990 template <class T> struct S<T*, int> {};
9992 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
9993 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
9994 int}. The resulting vector will be {double}, indicating that `T'
9995 is bound to `double'. */
9997 static tree
10000 {
10005 UNIFY_ALLOW_NONE))
10016 }
10018 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10019 Pick the most specialized template, and return the corresponding
10020 instantiation, or if there is no corresponding instantiation, the
10021 template itself. If there is no most specialized template,
10022 error_mark_node is returned. If there are no templates at all,
10023 NULL_TREE is returned. */
10025 tree
10027 tree instantiations;
10028 {
10037 {
10041 ;
10042 else
10043 {
10045 {
10049 }
10051 }
10052 }
10055 {
10060 }
10063 }
10065 /* Return the most specialized of the list of templates in FNS that can
10066 produce an instantiation matching DECL, given the explicit template
10067 arguments EXPLICIT_ARGS. */
10069 static tree
10072 {
10077 {
10083 }
10086 }
10088 /* If DECL is a specialization of some template, return the most
10089 general such template. Otherwise, returns NULL_TREE.
10091 For example, given:
10093 template <class T> struct S { template <class U> void f(U); };
10095 if TMPL is `template <class U> void S<int>::f(U)' this will return
10096 the full template. This function will not trace past partial
10097 specializations, however. For example, given in addition:
10099 template <class T> struct S<T*> { template <class U> void f(U); };
10101 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10102 `template <class T> template <class U> S<T*>::f(U)'. */
10104 tree
10106 tree decl;
10107 {
10108 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10109 an immediate specialization. */
10111 {
10115 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10116 template friend. */
10121 }
10123 /* Look for more and more general templates. */
10125 {
10126 /* The DECL_TI_TEMPLATE can be a LOOKUP_EXPR or IDENTIFIER_NODE
10127 in some cases. (See cp-tree.h for details.) */
10131 /* Stop if we run into an explicitly specialized class template. */
10138 }
10141 }
10143 /* Return the most specialized of the class template specializations
10144 of TMPL which can produce an instantiation matching ARGS, or
10145 error_mark_node if the choice is ambiguous. */
10147 static tree
10149 tree tmpl;
10150 tree args;
10151 {
10153 tree t;
10154 tree champ;
10159 {
10160 tree spec_args
10163 {
10166 }
10167 }
10176 {
10179 ;
10180 else
10181 {
10183 {
10187 }
10189 }
10190 }
10193 {
10197 }
10200 }
10202 /* Explicitly instantiate DECL. */
10204 void
10206 {
10211 /* An error occurred, for which grokdeclarator has already issued
10212 an appropriate message. */
10215 {
10218 }
10220 {
10221 /* There is an asymmetry here in the way VAR_DECLs and
10222 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10223 the latter, the DECL we get back will be marked as a
10224 template instantiation, and the appropriate
10225 DECL_TEMPLATE_INFO will be set up. This does not happen for
10226 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10227 should handle VAR_DECLs as it currently handles
10228 FUNCTION_DECLs. */
10231 {
10234 }
10235 }
10237 {
10240 }
10241 else
10244 /* Check for various error cases. Note that if the explicit
10245 instantiation is valid the RESULT will currently be marked as an
10246 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10247 until we get here. */
10250 {
10251 /* DR 259 [temp.spec].
10253 Both an explicit instantiation and a declaration of an explicit
10254 specialization shall not appear in a program unless the explicit
10255 instantiation follows a declaration of the explicit specialization.
10257 For a given set of template parameters, if an explicit
10258 instantiation of a template appears after a declaration of an
10259 explicit specialization for that template, the explicit
10260 instantiation has no effect. */
10262 }
10264 {
10265 /* [temp.spec]
10267 No program shall explicitly instantiate any template more
10268 than once.
10270 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10271 instantiation was `extern' and the second is not, and EXTERN_P for
10272 the opposite case. If -frepo, chances are we already got marked
10273 as an explicit instantiation because of the repo file. */
10277 /* If we've already instantiated the template, just return now. */
10280 }
10282 {
10285 }
10287 {
10290 }
10296 ;
10298 {
10302 }
10303 else
10305 storage);
10312 }
10314 void
10316 tree t;
10318 {
10324 {
10327 }
10328 }
10330 /* Perform an explicit instantiation of template class T. STORAGE, if
10331 non-null, is the RID for extern, inline or static. COMPLAIN is
10332 nonzero if this is called from the parser, zero if called recursively,
10333 since the standard is unclear (as detailed below). */
10335 void
10338 tsubst_flags_t complain;
10339 {
10348 {
10351 }
10355 /* With -fexternal-templates, explicit instantiations are treated the same
10356 as implicit ones. */
10361 {
10364 t);
10366 }
10369 {
10380 else
10381 {
10383 storage);
10385 }
10386 }
10389 {
10390 /* DR 259 [temp.spec].
10392 Both an explicit instantiation and a declaration of an explicit
10393 specialization shall not appear in a program unless the explicit
10394 instantiation follows a declaration of the explicit specialization.
10396 For a given set of template parameters, if an explicit
10397 instantiation of a template appears after a declaration of an
10398 explicit specialization for that template, the explicit
10399 instantiation has no effect. */
10401 }
10403 {
10404 /* [temp.spec]
10406 No program shall explicitly instantiate any template more
10407 than once.
10409 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10410 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10411 are we already got marked as an explicit instantiation because of the
10412 repo file. All these cases are OK. */
10417 /* If we've already instantiated the template, just return now. */
10420 }
10428 {
10429 tree tmp;
10431 /* In contrast to implicit instantiation, where only the
10432 declarations, and not the definitions, of members are
10433 instantiated, we have here:
10435 [temp.explicit]
10437 The explicit instantiation of a class template specialization
10438 implies the instantiation of all of its members not
10439 previously explicitly specialized in the translation unit
10440 containing the explicit instantiation.
10442 Of course, we can't instantiate member template classes, since
10443 we don't have any arguments for them. Note that the standard
10444 is unclear on whether the instantiation of the members are
10445 *explicit* instantiations or not. We choose to be generous,
10446 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10447 the explicit instantiation of a class where some of the members
10448 have no definition in the current translation unit. */
10454 {
10459 }
10463 {
10468 }
10474 }
10475 }
10477 /* Given a function DECL, which is a specialization of TMPL, modify
10478 DECL to be a re-instantiation of TMPL with the same template
10479 arguments. TMPL should be the template into which tsubst'ing
10480 should occur for DECL, not the most general template.
10482 One reason for doing this is a scenario like this:
10484 template <class T>
10485 void f(const T&, int i);
10487 void g() { f(3, 7); }
10489 template <class T>
10490 void f(const T& t, const int i) { }
10492 Note that when the template is first instantiated, with
10493 instantiate_template, the resulting DECL will have no name for the
10494 first parameter, and the wrong type for the second. So, when we go
10495 to instantiate the DECL, we regenerate it. */
10497 static void
10499 tree decl;
10500 tree tmpl;
10501 {
10502 /* The most general version of TMPL. */
10503 tree gen_tmpl;
10504 /* The arguments used to instantiate DECL, from the most general
10505 template. */
10506 tree args;
10507 tree code_pattern;
10508 tree new_decl;
10514 /* Unregister the specialization so that when we tsubst we will not
10515 just return DECL. We don't have to unregister DECL from TMPL
10516 because if would only be registered there if it were a partial
10517 instantiation of a specialization, which it isn't: it's a full
10518 instantiation. */
10523 /* If the DECL was not unregistered then something peculiar is
10524 happening: we created a specialization but did not call
10525 register_specialization for it. */
10528 /* Do the substitution to get the new declaration. */
10532 {
10533 /* Set up DECL_INITIAL, since tsubst doesn't. */
10538 }
10540 {
10541 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10542 new decl. */
10544 /* And don't complain about a duplicate definition. */
10546 }
10550 /* The immediate parent of the new template is still whatever it was
10551 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10552 general template. We also reset the DECL_ASSEMBLER_NAME since
10553 tsubst always calculates the name as if the function in question
10554 were really a template instance, and sometimes, with friend
10555 functions, this is not so. See tsubst_friend_function for
10556 details. */
10562 /* Call duplicate decls to merge the old and new declarations. */
10565 /* Now, re-register the specialization. */
10567 }
10569 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10570 substituted to get DECL. */
10572 static tree
10574 {
10577 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10578 for the instantiation. This is not always the most general
10579 template. Consider, for example:
10581 template <class T>
10582 struct S { template <class U> void f();
10583 template <> void f<int>(); };
10585 and an instantiation of S<double>::f<int>. We want TD to be the
10586 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10588 more general template. */
10590 /* We must also deal with friend templates. Given:
10592 template <class T> struct S {
10593 template <class U> friend void f() {};
10594 };
10596 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10597 so far as the language is concerned, but that's still
10598 where we get the pattern for the instantiation from. On
10599 other hand, if the definition comes outside the class, say:
10601 template <class T> struct S {
10602 template <class U> friend void f();
10603 };
10604 template <class U> friend void f() {}
10606 we don't need to look any further. That's what the check for
10607 DECL_INITIAL is for. */
10611 {
10612 /* The present template, TD, should not be a definition. If it
10613 were a definition, we should be using it! Note that we
10614 cannot restructure the loop to just keep going until we find
10615 a template with a definition, since that might go too far if
10616 a specialization was declared, but not defined. */
10621 /* Fetch the more general template. */
10623 }
10626 }
10628 /* Produce the definition of D, a _DECL generated from a template. If
10629 DEFER_OK is nonzero, then we don't have to actually do the
10630 instantiation now; we just have to do it sometime. */
10632 tree
10634 tree d;
10636 {
10638 tree gen_args;
10639 tree args;
10640 tree td;
10641 tree code_pattern;
10642 tree spec;
10643 tree gen_tmpl;
10649 /* This function should only be used to instantiate templates for
10650 functions and static member variables. */
10654 /* Variables are never deferred; if instantiation is required, they
10655 are instantiated right away. That allows for better code in the
10656 case that an expression refers to the value of the variable --
10657 if the variable has a constant value the referring expression can
10658 take advantage of that fact. */
10662 /* Don't instantiate cloned functions. Instead, instantiate the
10663 functions they cloned. */
10668 /* D has already been instantiated. It might seem reasonable to
10669 check whether or not D is an explicit instantiation, and, if so,
10670 stop here. But when an explicit instantiation is deferred
10671 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10672 is set, even though we still need to do the instantiation. */
10675 /* If we already have a specialization of this declaration, then
10676 there's no reason to instantiate it. Note that
10677 retrieve_specialization gives us both instantiations and
10678 specializations, so we must explicitly check
10679 DECL_TEMPLATE_SPECIALIZATION. */
10686 /* This needs to happen before any tsubsting. */
10692 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10693 for the instantiation. */
10697 /* In the case of a friend template whose definition is provided
10698 outside the class, we may have too many arguments. Drop the ones
10699 we don't need. */
10701 TMPL_PARMS_DEPTH
10706 else
10713 {
10714 /* Let the repository code that this template definition is
10715 available.
10717 The repository doesn't need to know about cloned functions
10718 because they never actually show up in the object file. It
10719 does need to know about the clones; those are the symbols
10720 that the linker will be emitting error messages about. */
10723 {
10724 tree t;
10730 }
10731 else
10735 {
10737 {
10740 }
10742 {
10745 }
10746 else
10748 }
10752 }
10755 {
10756 /* Recheck the substitutions to obtain any warning messages
10757 about ignoring cv qualifiers. */
10761 /* Make sure that we can see identifiers, and compute access
10762 correctly. D is already the target FUNCTION_DECL with the
10763 right context. */
10767 {
10771 /* Don't simply tsubst the function type, as that will give
10772 duplicate warnings about poor parameter qualifications.
10773 The function arguments are the same as the decl_arguments
10774 without the top level cv qualifiers. */
10776 }
10780 }
10784 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10786 /* Reject all external templates except inline functions. */
10792 /* Defer all other templates, unless we have been explicitly
10793 forbidden from doing so. We restore the source position here
10794 because it's used by add_pending_template. */
10796 {
10802 /* [temp.explicit]
10804 The definition of a non-exported function template, a
10805 non-exported member function template, or a non-exported
10806 member function or static data member of a class template
10807 shall be present in every translation unit in which it is
10808 explicitly instantiated. */
10809 pedwarn
10814 }
10820 /* We're now committed to instantiating this template. Mark it as
10821 instantiated so that recursive calls to instantiate_decl do not
10822 try to instantiate it again. */
10825 /* Regenerate the declaration in case the template has been modified
10826 by a subsequent redeclaration. */
10829 /* We already set the file and line above. Reset them now in case
10830 they changed as a result of calling regenerate_decl_from_template. */
10835 {
10836 /* Clear out DECL_RTL; whatever was there before may not be right
10837 since we've reset the type of the declaration. */
10843 else
10844 {
10847 }
10852 }
10854 {
10855 htab_t saved_local_specializations;
10856 tree subst_decl;
10857 tree tmpl_parm;
10858 tree spec_parm;
10860 /* Save away the current list, in case we are instantiating one
10861 template from within the body of another. */
10864 /* Set up the list of local specializations. */
10866 hash_local_specialization,
10867 eq_local_specializations,
10868 NULL);
10870 /* Set up context. */
10873 /* Create substitution entries for the parameters. */
10878 {
10882 }
10884 {
10888 }
10891 /* Substitute into the body of the function. */
10895 /* We don't need the local specializations any more. */
10899 /* Finish the function. */
10901 }
10903 /* We're not deferring instantiation any more. */
10909 out:
10918 }
10920 /* Run through the list of templates that we wish we could
10921 instantiate, and instantiate any we can. */
10923 int
10925 {
10931 do
10932 {
10937 {
10943 {
10944 tree fn;
10947 {
10951 fn;
10956 {
10959 }
10960 }
10963 /* If INSTANTIATION has been instantiated, then we don't
10964 need to consider it again in the future. */
10966 else
10967 {
10970 }
10971 }
10972 else
10973 {
10976 {
10980 {
10983 }
10984 }
10988 /* If INSTANTIATION has been instantiated, then we don't
10989 need to consider it again in the future. */
10991 else
10992 {
10995 }
10996 }
10999 }
11001 }
11005 }
11007 /* Substitute ARGVEC into T, which is a list of initializers for
11008 either base class or a non-static data member. The TREE_PURPOSEs
11009 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11010 instantiate_decl. */
11012 static tree
11015 {
11019 {
11020 tree decl;
11021 tree init;
11022 tree val;
11025 NULL_TREE);
11027 NULL_TREE);
11030 ;
11039 {
11042 }
11043 }
11045 }
11047 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11049 static void
11051 tree decl;
11052 {
11057 else
11059 }
11061 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11062 is the instantiation (which should have been created with
11063 start_enum) and ARGS are the template arguments to use. */
11065 static void
11067 tree tag;
11068 tree newtag;
11069 tree args;
11070 {
11071 tree e;
11074 {
11075 tree value;
11077 /* Copy node and set type */
11082 /* Note that in a template enum, the TREE_VALUE is the
11083 CONST_DECL, not the corresponding INTEGER_CST. */
11086 NULL_TREE);
11088 /* Give this enumeration constant the correct access. */
11091 /* Actually build the enumerator itself. */
11093 }
11098 }
11100 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11101 its type -- but without substituting the innermost set of template
11102 arguments. So, innermost set of template parameters will appear in
11103 the type. */
11105 tree
11107 tree decl;
11108 {
11109 tree fn_type;
11110 tree tmpl;
11111 tree targs;
11112 tree tparms;
11120 /* There should be as many levels of arguments as there are levels
11121 of parameters. */
11127 /* No substitution is necessary. */
11128 ;
11129 else
11130 {
11132 tree partial_args;
11134 /* Replace the innermost level of the TARGS with NULL_TREEs to
11135 let tsubst know not to substitute for those parameters. */
11144 /* Make sure that we can see identifiers, and compute access
11145 correctly. We can just use the context of DECL for the
11146 partial substitution here. It depends only on outer template
11147 parameters, regardless of whether the innermost level is
11148 specialized or not. */
11151 /* Now, do the (partial) substitution to figure out the
11152 appropriate function type. */
11155 /* Substitute into the template parameters to obtain the real
11156 innermost set of parameters. This step is important if the
11157 innermost set of template parameters contains value
11158 parameters whose types depend on outer template parameters. */
11163 }
11166 }
11168 /* Return truthvalue if we're processing a template different from
11169 the last one involved in diagnostics. */
11170 int
11172 {
11174 }
11176 /* Remember current template involved in diagnostics. */
11177 void
11179 {
11181 }
11183 tree
11185 {
11187 }
11189 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11190 type. Return zero for ok, nonzero for disallowed. Issue error and
11191 warning messages under control of COMPLAIN. */
11193 static int
11195 tree type;
11196 tsubst_flags_t complain;
11197 {
11213 type);
11215 }
11217 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11218 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11220 static bool
11222 {
11223 tree scope;
11225 /* [temp.dep.type]
11227 A type is dependent if it is:
11229 -- a template parameter. */
11232 /* -- a qualified-id with a nested-name-specifier which contains a
11233 class-name that names a dependent type or whose unqualified-id
11234 names a dependent type. */
11237 /* -- a cv-qualified type where the cv-unqualified type is
11238 dependent. */
11240 /* -- a compound type constructed from any dependent type. */
11250 {
11251 tree arg_type;
11256 arg_type;
11261 }
11262 /* -- an array type constructed from any dependent type or whose
11263 size is specified by a constant expression that is
11264 value-dependent. */
11266 {
11268 && ((value_dependent_expression_p
11270 || (type_dependent_expression_p
11274 }
11275 /* -- a template-id in which either the template name is a template
11276 parameter or any of the template arguments is a dependent type or
11277 an expression that is type-dependent or value-dependent.
11279 This language seems somewhat confused; for example, it does not
11280 discuss template template arguments. Therefore, we use the
11281 definition for dependent template arguments in [temp.dep.temp]. */
11283 && (dependent_template_id_p
11289 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11290 expression is not type-dependent, then it should already been
11291 have resolved. */
11294 /* The standard does not specifically mention types that are local
11295 to template functions or local classes, but they should be
11296 considered dependent too. For example:
11298 template <int I> void f() {
11299 enum E { a = I };
11300 S<sizeof (E)> s;
11301 }
11303 The size of `E' cannot be known until the value of `I' has been
11304 determined. Therefore, `E' must be considered dependent. */
11311 /* Other types are non-dependent. */
11313 }
11315 /* Returns TRUE if TYPE is dependent, in the sense of
11316 [temp.dep.type]. */
11318 bool
11320 {
11321 /* If there are no template parameters in scope, then there can't be
11322 any dependent types. */
11326 /* If the type is NULL, we have not computed a type for the entity
11327 in question; in that case, the type is dependent. */
11331 /* Erroneous types can be considered non-dependent. */
11335 /* If we have not already computed the appropriate value for TYPE,
11336 do so now. */
11338 {
11341 }
11344 }
11346 /* Returns TRUE if the EXPRESSION is value-dependent. */
11348 bool
11350 {
11354 /* A name declared with a dependent type. */
11359 /* A non-type template parameter. */
11364 /* A constant with integral or enumeration type and is initialized
11365 with an expression that is value-dependent. */
11372 /* These expressions are value-dependent if the type to which the
11373 cast occurs is dependent. */
11381 /* A `sizeof' expression where the sizeof operand is a type is
11382 value-dependent if the type is dependent. If the type was not
11383 dependent, we would no longer have a SIZEOF_EXPR, so any
11384 SIZEOF_EXPR is dependent. */
11387 /* A constant expression is value-dependent if any subexpression is
11388 value-dependent. */
11390 {
11392 {
11400 || (value_dependent_expression_p
11403 {
11406 /* In some cases, some of the operands may be missing.
11407 (For example, in the case of PREDECREMENT_EXPR, the
11408 amount to increment by may be missing.) That doesn't
11409 make the expression dependent. */
11411 && (value_dependent_expression_p
11415 }
11416 }
11417 }
11419 /* The expression is not value-dependent. */
11421 }
11423 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11424 [temp.dep.expr]. */
11426 bool
11428 tree expression;
11429 {
11433 /* Some expression forms are never type-dependent. */
11443 /* The types of these expressions depends only on the type to which
11444 the cast occurs. */
11451 /* The types of these expressions depends only on the type created
11452 by the expression. */
11460 && (dependent_template_id_p
11466 }
11468 /* Returns TRUE if the ARG (a template argument) is dependent. */
11470 bool
11472 {
11481 else
11484 }
11486 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11488 static bool
11490 {
11499 }
11501 /* Returns TRUE if the template TMPL is dependent. */
11503 bool
11505 {
11506 /* Template template parameters are dependent. */
11510 /* So are member templates of dependent classes. */
11514 }
11516 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11517 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11518 can be found. Note that this function peers inside uninstantiated
11519 templates and therefore should be used only in extremely limited
11520 situations. */
11522 tree
11524 {
11525 tree scope;
11526 tree name;
11527 tree decl;
11536 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11537 it first before we can figure out what NAME refers to. */
11540 /* If we don't know what SCOPE refers to, then we cannot resolve the
11541 TYPENAME_TYPE. */
11544 /* If the SCOPE is a template type parameter, we have no way of
11545 resolving the name. */
11548 /* If the SCOPE is not the current instantiation, there's no reason
11549 to look inside it. */
11552 /* If SCOPE is a partial instantiation, it will not have a valid
11553 TYPE_FIELDS list, so use the original template. */
11555 /* Enter the SCOPE so that name lookup will be resolved as if we
11556 were in the class definition. In particular, SCOPE will no
11557 longer be considered a dependent type. */
11559 /* Look up the declaration. */
11561 /* Obtain the set of qualifiers applied to the TYPE. */
11563 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11564 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11572 {
11573 tree tmpl;
11574 tree args;
11575 /* Obtain the template and the arguments. */
11578 /* Instantiate the template. */
11581 tf_error);
11582 }
11583 else
11585 /* Qualify the resulting type. */
11588 /* Leave the SCOPE. */
11592 }
11594 tree
11596 {
11597 tree t;
11601 }