1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000
3 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 GNU CC.
9 GNU CC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GNU CC 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 GNU CC; 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". */
47 /* The type of functions taking a tree, and some additional data, and
49 typedef int (*tree_fn_t) PARAMS ((tree, void*));
51 extern struct obstack permanent_obstack;
54 extern char *input_filename;
56 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
57 instantiations have been deferred, either because their definitions
58 were not yet available, or because we were putting off doing the
59 work. The TREE_PURPOSE of each entry is a SRCLOC indicating where
60 the instantiate request occurred; the TREE_VALUE is a either a DECL
61 (for a function or static data member), or a TYPE (for a class)
62 indicating what we are hoping to instantiate. */
63 static tree pending_templates;
64 static tree *template_tail = &pending_templates;
66 static tree maybe_templates;
67 static tree *maybe_template_tail = &maybe_templates;
69 int processing_template_parmlist;
70 static int template_header_count;
72 static tree saved_trees;
73 static varray_type inline_parm_levels;
74 static size_t inline_parm_levels_used;
76 #define obstack_chunk_alloc xmalloc
77 #define obstack_chunk_free free
79 #define UNIFY_ALLOW_NONE 0
80 #define UNIFY_ALLOW_MORE_CV_QUAL 1
81 #define UNIFY_ALLOW_LESS_CV_QUAL 2
82 #define UNIFY_ALLOW_DERIVED 4
83 #define UNIFY_ALLOW_INTEGER 8
85 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
86 virtual, or a base class of a virtual
88 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
89 type with the desired type. */
91 static int resolve_overloaded_unification PARAMS ((tree, tree, tree, tree,
92 unification_kind_t, int));
93 static int try_one_overload PARAMS ((tree, tree, tree, tree, tree,
94 unification_kind_t, int));
95 static int unify PARAMS ((tree, tree, tree, tree, int));
96 static void add_pending_template PARAMS ((tree));
97 static int push_tinst_level PARAMS ((tree));
98 static tree classtype_mangled_name PARAMS ((tree));
99 static char *mangle_class_name_for_template PARAMS ((char *, tree, tree));
100 static tree tsubst_expr_values PARAMS ((tree, tree));
101 static int list_eq PARAMS ((tree, tree));
102 static tree get_class_bindings PARAMS ((tree, tree, tree));
103 static tree coerce_template_parms PARAMS ((tree, tree, tree, int, int));
104 static void tsubst_enum PARAMS ((tree, tree, tree));
105 static tree add_to_template_args PARAMS ((tree, tree));
106 static tree add_outermost_template_args PARAMS ((tree, tree));
107 static void maybe_adjust_types_for_deduction PARAMS ((unification_kind_t, tree*,
109 static int type_unification_real PARAMS ((tree, tree, tree, tree,
110 int, unification_kind_t, int));
111 static void note_template_header PARAMS ((int));
112 static tree maybe_fold_nontype_arg PARAMS ((tree));
113 static tree convert_nontype_argument PARAMS ((tree, tree));
114 static tree convert_template_argument PARAMS ((tree, tree, tree, int,
116 static tree get_bindings_overload PARAMS ((tree, tree, tree));
117 static int for_each_template_parm PARAMS ((tree, tree_fn_t, void*));
118 static tree build_template_parm_index PARAMS ((int, int, int, tree, tree));
119 static int inline_needs_template_parms PARAMS ((tree));
120 static void push_inline_template_parms_recursive PARAMS ((tree, int));
121 static tree retrieve_specialization PARAMS ((tree, tree));
122 static tree retrieve_local_specialization PARAMS ((tree, tree));
123 static tree register_specialization PARAMS ((tree, tree, tree));
124 static tree register_local_specialization PARAMS ((tree, tree, tree));
125 static int unregister_specialization PARAMS ((tree, tree));
126 static tree reduce_template_parm_level PARAMS ((tree, tree, int));
127 static tree build_template_decl PARAMS ((tree, tree));
128 static int mark_template_parm PARAMS ((tree, void *));
129 static tree tsubst_friend_function PARAMS ((tree, tree));
130 static tree tsubst_friend_class PARAMS ((tree, tree));
131 static tree get_bindings_real PARAMS ((tree, tree, tree, int));
132 static int template_decl_level PARAMS ((tree));
133 static tree maybe_get_template_decl_from_type_decl PARAMS ((tree));
134 static int check_cv_quals_for_unify PARAMS ((int, tree, tree));
135 static tree tsubst_template_arg_vector PARAMS ((tree, tree, int));
136 static tree tsubst_template_parms PARAMS ((tree, tree, int));
137 static void regenerate_decl_from_template PARAMS ((tree, tree));
138 static tree most_specialized PARAMS ((tree, tree, tree));
139 static tree most_specialized_class PARAMS ((tree, tree));
140 static void set_mangled_name_for_template_decl PARAMS ((tree));
141 static int template_class_depth_real PARAMS ((tree, int));
142 static tree tsubst_aggr_type PARAMS ((tree, tree, int, tree, int));
143 static tree tsubst_decl PARAMS ((tree, tree, tree, tree));
144 static tree tsubst_arg_types PARAMS ((tree, tree, int, tree));
145 static tree tsubst_function_type PARAMS ((tree, tree, int, tree));
146 static void check_specialization_scope PARAMS ((void));
147 static tree process_partial_specialization PARAMS ((tree));
148 static void set_current_access_from_decl PARAMS ((tree));
149 static void check_default_tmpl_args PARAMS ((tree, tree, int, int));
150 static tree tsubst_call_declarator_parms PARAMS ((tree, tree, int, tree));
151 static tree get_template_base_recursive PARAMS ((tree, tree,
152 tree, tree, tree, int));
153 static tree get_template_base PARAMS ((tree, tree, tree, tree));
154 static tree try_class_unification PARAMS ((tree, tree, tree, tree));
155 static int coerce_template_template_parms PARAMS ((tree, tree, int,
157 static tree determine_specialization PARAMS ((tree, tree, tree *, int));
158 static int template_args_equal PARAMS ((tree, tree));
159 static void print_template_context PARAMS ((int));
160 static void tsubst_default_arguments PARAMS ((tree));
161 static tree for_each_template_parm_r PARAMS ((tree *, int *, void *));
163 /* Called once to initialize pt.c. */
168 ggc_add_tree_root (&pending_templates, 1);
169 ggc_add_tree_root (&maybe_templates, 1);
170 ggc_add_tree_root (&saved_trees, 1);
173 /* Do any processing required when DECL (a member template declaration
174 using TEMPLATE_PARAMETERS as its innermost parameter list) is
175 finished. Returns the TEMPLATE_DECL corresponding to DECL, unless
176 it is a specialization, in which case the DECL itself is returned. */
179 finish_member_template_decl (decl)
182 if (decl == NULL_TREE || decl == void_type_node)
184 else if (decl == error_mark_node)
185 /* By returning NULL_TREE, the parser will just ignore this
186 declaration. We have already issued the error. */
188 else if (TREE_CODE (decl) == TREE_LIST)
190 /* Assume that the class is the only declspec. */
191 decl = TREE_VALUE (decl);
192 if (IS_AGGR_TYPE (decl) && CLASSTYPE_TEMPLATE_INFO (decl)
193 && ! CLASSTYPE_TEMPLATE_SPECIALIZATION (decl))
195 tree tmpl = CLASSTYPE_TI_TEMPLATE (decl);
196 check_member_template (tmpl);
201 else if (TREE_CODE (decl) == FIELD_DECL)
202 cp_error ("data member `%D' cannot be a member template", decl);
203 else if (DECL_TEMPLATE_INFO (decl))
205 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
207 check_member_template (DECL_TI_TEMPLATE (decl));
208 return DECL_TI_TEMPLATE (decl);
214 cp_error ("invalid member template declaration `%D'", decl);
216 return error_mark_node;
219 /* Returns the template nesting level of the indicated class TYPE.
229 A<T>::B<U> has depth two, while A<T> has depth one.
230 Both A<T>::B<int> and A<int>::B<U> have depth one, if
231 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
234 This function is guaranteed to return 0 if passed NULL_TREE so
235 that, for example, `template_class_depth (current_class_type)' is
239 template_class_depth_real (type, count_specializations)
241 int count_specializations;
246 type && TREE_CODE (type) != NAMESPACE_DECL;
247 type = (TREE_CODE (type) == FUNCTION_DECL)
248 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
250 if (TREE_CODE (type) != FUNCTION_DECL)
252 if (CLASSTYPE_TEMPLATE_INFO (type)
253 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
254 && ((count_specializations
255 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
256 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
261 if (DECL_TEMPLATE_INFO (type)
262 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
263 && ((count_specializations
264 && DECL_TEMPLATE_SPECIALIZATION (type))
265 || uses_template_parms (DECL_TI_ARGS (type))))
273 /* Returns the template nesting level of the indicated class TYPE.
274 Like template_class_depth_real, but instantiations do not count in
278 template_class_depth (type)
281 return template_class_depth_real (type, /*count_specializations=*/0);
284 /* Returns 1 if processing DECL as part of do_pending_inlines
285 needs us to push template parms. */
288 inline_needs_template_parms (decl)
291 if (! DECL_TEMPLATE_INFO (decl))
294 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
295 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
298 /* Subroutine of maybe_begin_member_template_processing.
299 Push the template parms in PARMS, starting from LEVELS steps into the
300 chain, and ending at the beginning, since template parms are listed
304 push_inline_template_parms_recursive (parmlist, levels)
308 tree parms = TREE_VALUE (parmlist);
312 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
314 ++processing_template_decl;
315 current_template_parms
316 = tree_cons (build_int_2 (0, processing_template_decl),
317 parms, current_template_parms);
318 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
321 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
323 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
324 my_friendly_assert (DECL_P (parm), 0);
326 switch (TREE_CODE (parm))
335 /* Make a CONST_DECL as is done in process_template_parm.
336 It is ugly that we recreate this here; the original
337 version built in process_template_parm is no longer
339 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
341 SET_DECL_ARTIFICIAL (decl);
342 DECL_INITIAL (decl) = DECL_INITIAL (parm);
343 SET_DECL_TEMPLATE_PARM_P (decl);
349 my_friendly_abort (0);
354 /* Restore the template parameter context for a member template or
355 a friend template defined in a class definition. */
358 maybe_begin_member_template_processing (decl)
364 if (inline_needs_template_parms (decl))
366 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
367 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
369 if (DECL_TEMPLATE_SPECIALIZATION (decl))
372 parms = TREE_CHAIN (parms);
375 push_inline_template_parms_recursive (parms, levels);
378 /* Remember how many levels of template parameters we pushed so that
379 we can pop them later. */
380 if (!inline_parm_levels)
381 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
382 if (inline_parm_levels_used == inline_parm_levels->num_elements)
383 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
384 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
385 ++inline_parm_levels_used;
388 /* Undo the effects of begin_member_template_processing. */
391 maybe_end_member_template_processing ()
395 if (!inline_parm_levels_used)
398 --inline_parm_levels_used;
400 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
403 --processing_template_decl;
404 current_template_parms = TREE_CHAIN (current_template_parms);
409 /* Returns non-zero iff T is a member template function. We must be
412 template <class T> class C { void f(); }
414 Here, f is a template function, and a member, but not a member
415 template. This function does not concern itself with the origin of
416 T, only its present state. So if we have
418 template <class T> class C { template <class U> void f(U); }
420 then neither C<int>::f<char> nor C<T>::f<double> is considered
421 to be a member template. But, `template <class U> void
422 C<int>::f(U)' is considered a member template. */
425 is_member_template (t)
428 if (!DECL_FUNCTION_TEMPLATE_P (t))
429 /* Anything that isn't a function or a template function is
430 certainly not a member template. */
433 /* A local class can't have member templates. */
434 if (decl_function_context (t))
437 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
438 /* If there are more levels of template parameters than
439 there are template classes surrounding the declaration,
440 then we have a member template. */
441 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
442 template_class_depth (DECL_CONTEXT (t))));
446 /* Returns non-zero iff T is a member template class. See
447 is_member_template for a description of what precisely constitutes
448 a member template. */
451 is_member_template_class (t)
454 if (!DECL_CLASS_TEMPLATE_P (t))
455 /* Anything that isn't a class template, is certainly not a member
459 if (!DECL_CLASS_SCOPE_P (t))
460 /* Anything whose context isn't a class type is surely not a
464 /* If there are more levels of template parameters than there are
465 template classes surrounding the declaration, then we have a
467 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
468 template_class_depth (DECL_CONTEXT (t)));
472 /* Return a new template argument vector which contains all of ARGS,
473 but has as its innermost set of arguments the EXTRA_ARGS. The
474 resulting vector will be built on a temporary obstack, and so must
475 be explicitly copied to the permanent obstack, if required. */
478 add_to_template_args (args, extra_args)
487 extra_depth = TMPL_ARGS_DEPTH (extra_args);
488 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
490 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
491 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
493 for (j = 1; j <= extra_depth; ++j, ++i)
494 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
499 /* Like add_to_template_args, but only the outermost ARGS are added to
500 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
501 (EXTRA_ARGS) levels are added. This function is used to combine
502 the template arguments from a partial instantiation with the
503 template arguments used to attain the full instantiation from the
504 partial instantiation. */
507 add_outermost_template_args (args, extra_args)
513 /* If there are more levels of EXTRA_ARGS than there are ARGS,
514 something very fishy is going on. */
515 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
518 /* If *all* the new arguments will be the EXTRA_ARGS, just return
520 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
523 /* For the moment, we make ARGS look like it contains fewer levels. */
524 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
526 new_args = add_to_template_args (args, extra_args);
528 /* Now, we restore ARGS to its full dimensions. */
529 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
534 /* We've got a template header coming up; push to a new level for storing
538 begin_template_parm_list ()
540 /* We use a non-tag-transparent scope here, which causes pushtag to
541 put tags in this scope, rather than in the enclosing class or
542 namespace scope. This is the right thing, since we want
543 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
544 global template class, push_template_decl handles putting the
545 TEMPLATE_DECL into top-level scope. For a nested template class,
548 template <class T> struct S1 {
549 template <class T> struct S2 {};
552 pushtag contains special code to call pushdecl_with_scope on the
553 TEMPLATE_DECL for S2. */
554 begin_scope (sk_template_parms);
555 ++processing_template_decl;
556 ++processing_template_parmlist;
557 note_template_header (0);
560 /* This routine is called when a specialization is declared. If it is
561 illegal to declare a specialization here, an error is reported. */
564 check_specialization_scope ()
566 tree scope = current_scope ();
570 An explicit specialization shall be declared in the namespace of
571 which the template is a member, or, for member templates, in the
572 namespace of which the enclosing class or enclosing class
573 template is a member. An explicit specialization of a member
574 function, member class or static data member of a class template
575 shall be declared in the namespace of which the class template
577 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
578 cp_error ("explicit specialization in non-namespace scope `%D'",
583 In an explicit specialization declaration for a member of a class
584 template or a member template that appears in namespace scope,
585 the member template and some of its enclosing class templates may
586 remain unspecialized, except that the declaration shall not
587 explicitly specialize a class member template if its enclosing
588 class templates are not explicitly specialized as well. */
589 if (current_template_parms)
590 cp_error ("enclosing class templates are not explicitly specialized");
593 /* We've just seen template <>. */
596 begin_specialization ()
598 begin_scope (sk_template_spec);
599 note_template_header (1);
600 check_specialization_scope ();
603 /* Called at then end of processing a declaration preceeded by
607 end_specialization ()
610 reset_specialization ();
613 /* Any template <>'s that we have seen thus far are not referring to a
614 function specialization. */
617 reset_specialization ()
619 processing_specialization = 0;
620 template_header_count = 0;
623 /* We've just seen a template header. If SPECIALIZATION is non-zero,
624 it was of the form template <>. */
627 note_template_header (specialization)
630 processing_specialization = specialization;
631 template_header_count++;
634 /* We're beginning an explicit instantiation. */
637 begin_explicit_instantiation ()
639 ++processing_explicit_instantiation;
644 end_explicit_instantiation ()
646 my_friendly_assert(processing_explicit_instantiation > 0, 0);
647 --processing_explicit_instantiation;
650 /* The TYPE is being declared. If it is a template type, that means it
651 is a partial specialization. Do appropriate error-checking. */
654 maybe_process_partial_specialization (type)
657 if (IS_AGGR_TYPE (type) && CLASSTYPE_USE_TEMPLATE (type))
659 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
660 && !COMPLETE_TYPE_P (type))
662 if (current_namespace
663 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
665 cp_pedwarn ("specializing `%#T' in different namespace", type);
666 cp_pedwarn_at (" from definition of `%#D'",
667 CLASSTYPE_TI_TEMPLATE (type));
669 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
670 if (processing_template_decl)
671 push_template_decl (TYPE_MAIN_DECL (type));
673 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
674 cp_error ("specialization of `%T' after instantiation", type);
676 else if (processing_specialization)
677 cp_error ("explicit specialization of non-template `%T'", type);
680 /* Retrieve the specialization (in the sense of [temp.spec] - a
681 specialization is either an instantiation or an explicit
682 specialization) of TMPL for the given template ARGS. If there is
683 no such specialization, return NULL_TREE. The ARGS are a vector of
684 arguments, or a vector of vectors of arguments, in the case of
685 templates with more than one level of parameters. */
688 retrieve_specialization (tmpl, args)
694 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
696 /* There should be as many levels of arguments as there are
697 levels of parameters. */
698 my_friendly_assert (TMPL_ARGS_DEPTH (args)
699 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
702 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
705 if (comp_template_args (TREE_PURPOSE (s), args))
706 return TREE_VALUE (s);
711 /* Like retrieve_speciailization, but for local declarations. FN is
712 the function in which we are looking for an instantiation. */
715 retrieve_local_specialization (tmpl, fn)
719 tree s = purpose_member (fn, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
720 return s ? TREE_VALUE (s) : NULL_TREE;
723 /* Returns non-zero iff DECL is a specialization of TMPL. */
726 is_specialization_of (decl, tmpl)
732 if (TREE_CODE (decl) == FUNCTION_DECL)
736 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
742 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
744 for (t = TREE_TYPE (decl);
746 t = CLASSTYPE_USE_TEMPLATE (t)
747 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
748 if (same_type_p (TYPE_MAIN_VARIANT (t),
749 TYPE_MAIN_VARIANT (TREE_TYPE (tmpl))))
756 /* Register the specialization SPEC as a specialization of TMPL with
757 the indicated ARGS. Returns SPEC, or an equivalent prior
758 declaration, if available. */
761 register_specialization (spec, tmpl, args)
768 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
770 if (TREE_CODE (spec) == FUNCTION_DECL
771 && uses_template_parms (DECL_TI_ARGS (spec)))
772 /* This is the FUNCTION_DECL for a partial instantiation. Don't
773 register it; we want the corresponding TEMPLATE_DECL instead.
774 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
775 the more obvious `uses_template_parms (spec)' to avoid problems
776 with default function arguments. In particular, given
779 template <class T> void f(T t1, T t = T())
781 the default argument expression is not substituted for in an
782 instantiation unless and until it is actually needed. */
785 /* There should be as many levels of arguments as there are
786 levels of parameters. */
787 my_friendly_assert (TMPL_ARGS_DEPTH (args)
788 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
791 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
795 tree fn = TREE_VALUE (s);
797 /* We can sometimes try to re-register a specialization that we've
798 already got. In particular, regenerate_decl_from_template
799 calls duplicate_decls which will update the specialization
800 list. But, we'll still get called again here anyhow. It's
801 more convenient to simply allow this than to try to prevent it. */
804 else if (comp_template_args (TREE_PURPOSE (s), args))
806 if (DECL_TEMPLATE_SPECIALIZATION (spec))
808 if (DECL_TEMPLATE_INSTANTIATION (fn))
811 || DECL_EXPLICIT_INSTANTIATION (fn))
813 cp_error ("specialization of %D after instantiation",
819 /* This situation should occur only if the first
820 specialization is an implicit instantiation,
821 the second is an explicit specialization, and
822 the implicit instantiation has not yet been
823 used. That situation can occur if we have
824 implicitly instantiated a member function and
825 then specialized it later.
827 We can also wind up here if a friend
828 declaration that looked like an instantiation
829 turns out to be a specialization:
831 template <class T> void foo(T);
832 class S { friend void foo<>(int) };
833 template <> void foo(int);
835 We transform the existing DECL in place so that
836 any pointers to it become pointers to the
839 If there was a definition for the template, but
840 not for the specialization, we want this to
841 look as if there is no definition, and vice
843 DECL_INITIAL (fn) = NULL_TREE;
844 duplicate_decls (spec, fn);
849 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
851 duplicate_decls (spec, fn);
858 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
859 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
864 /* Unregister the specialization SPEC as a specialization of TMPL.
865 Returns nonzero if the SPEC was listed as a specialization of
869 unregister_specialization (spec, tmpl)
875 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
877 s = &TREE_CHAIN (*s))
878 if (TREE_VALUE (*s) == spec)
880 *s = TREE_CHAIN (*s);
887 /* Like register_specialization, but for local declarations. FN is
888 the function in which we are registering SPEC, an instantiation of
892 register_local_specialization (spec, tmpl, fn)
897 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
898 = tree_cons (fn, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
903 /* Print the list of candidate FNS in an error message. */
906 print_candidates (fns)
911 const char *str = "candidates are:";
913 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
917 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
918 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
923 /* Returns the template (one of the functions given by TEMPLATE_ID)
924 which can be specialized to match the indicated DECL with the
925 explicit template args given in TEMPLATE_ID. The DECL may be
926 NULL_TREE if none is available. In that case, the functions in
927 TEMPLATE_ID are non-members.
929 If NEED_MEMBER_TEMPLATE is non-zero the function is known to be a
930 specialization of a member template.
932 The template args (those explicitly specified and those deduced)
933 are output in a newly created vector *TARGS_OUT.
935 If it is impossible to determine the result, an error message is
936 issued. The error_mark_node is returned to indicate failure. */
939 determine_specialization (template_id, decl, targs_out,
940 need_member_template)
944 int need_member_template;
949 tree candidates = NULL_TREE;
950 tree templates = NULL_TREE;
952 *targs_out = NULL_TREE;
954 if (template_id == error_mark_node)
955 return error_mark_node;
957 fns = TREE_OPERAND (template_id, 0);
958 explicit_targs = TREE_OPERAND (template_id, 1);
960 if (fns == error_mark_node)
961 return error_mark_node;
963 /* Check for baselinks. */
964 if (BASELINK_P (fns))
965 fns = TREE_VALUE (fns);
967 if (!is_overloaded_fn (fns))
969 cp_error ("`%D' is not a function template", fns);
970 return error_mark_node;
973 for (; fns; fns = OVL_NEXT (fns))
977 tree fn = OVL_CURRENT (fns);
979 if (TREE_CODE (fn) == TEMPLATE_DECL)
980 /* DECL might be a specialization of FN. */
982 else if (need_member_template)
983 /* FN is an ordinary member function, and we need a
984 specialization of a member template. */
986 else if (TREE_CODE (fn) != FUNCTION_DECL)
987 /* We can get IDENTIFIER_NODEs here in certain erroneous
990 else if (!DECL_FUNCTION_MEMBER_P (fn))
991 /* This is just an ordinary non-member function. Nothing can
992 be a specialization of that. */
998 /* This is an ordinary member function. However, since
999 we're here, we can assume it's enclosing class is a
1000 template class. For example,
1002 template <typename T> struct S { void f(); };
1003 template <> void S<int>::f() {}
1005 Here, S<int>::f is a non-template, but S<int> is a
1006 template class. If FN has the same type as DECL, we
1007 might be in business. */
1008 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1009 TREE_TYPE (TREE_TYPE (fn))))
1010 /* The return types differ. */
1013 /* Adjust the type of DECL in case FN is a static member. */
1014 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1015 if (DECL_STATIC_FUNCTION_P (fn)
1016 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1017 decl_arg_types = TREE_CHAIN (decl_arg_types);
1019 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1022 candidates = tree_cons (NULL_TREE, fn, candidates);
1027 /* See whether this function might be a specialization of this
1029 targs = get_bindings (tmpl, decl, explicit_targs);
1032 /* We cannot deduce template arguments that when used to
1033 specialize TMPL will produce DECL. */
1036 /* Save this template, and the arguments deduced. */
1037 templates = tree_cons (targs, tmpl, templates);
1040 if (templates && TREE_CHAIN (templates))
1046 It is possible for a specialization with a given function
1047 signature to be instantiated from more than one function
1048 template. In such cases, explicit specification of the
1049 template arguments must be used to uniquely identify the
1050 function template specialization being specialized.
1052 Note that here, there's no suggestion that we're supposed to
1053 determine which of the candidate templates is most
1054 specialized. However, we, also have:
1058 Partial ordering of overloaded function template
1059 declarations is used in the following contexts to select
1060 the function template to which a function template
1061 specialization refers:
1063 -- when an explicit specialization refers to a function
1066 So, we do use the partial ordering rules, at least for now.
1067 This extension can only serve to make illegal programs legal,
1068 so it's safe. And, there is strong anecdotal evidence that
1069 the committee intended the partial ordering rules to apply;
1070 the EDG front-end has that behavior, and John Spicer claims
1071 that the committee simply forgot to delete the wording in
1072 [temp.expl.spec]. */
1073 tree tmpl = most_specialized (templates, decl, explicit_targs);
1074 if (tmpl && tmpl != error_mark_node)
1076 targs = get_bindings (tmpl, decl, explicit_targs);
1077 templates = tree_cons (targs, tmpl, NULL_TREE);
1081 if (templates == NULL_TREE && candidates == NULL_TREE)
1083 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1085 return error_mark_node;
1087 else if ((templates && TREE_CHAIN (templates))
1088 || (candidates && TREE_CHAIN (candidates))
1089 || (templates && candidates))
1091 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1093 chainon (candidates, templates);
1094 print_candidates (candidates);
1095 return error_mark_node;
1098 /* We have one, and exactly one, match. */
1101 /* It was a specialization of an ordinary member function in a
1103 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1104 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1107 /* It was a specialization of a template. */
1108 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1109 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1111 *targs_out = copy_node (targs);
1112 SET_TMPL_ARGS_LEVEL (*targs_out,
1113 TMPL_ARGS_DEPTH (*targs_out),
1114 TREE_PURPOSE (templates));
1117 *targs_out = TREE_PURPOSE (templates);
1118 return TREE_VALUE (templates);
1121 /* Check to see if the function just declared, as indicated in
1122 DECLARATOR, and in DECL, is a specialization of a function
1123 template. We may also discover that the declaration is an explicit
1124 instantiation at this point.
1126 Returns DECL, or an equivalent declaration that should be used
1127 instead if all goes well. Issues an error message if something is
1128 amiss. Returns error_mark_node if the error is not easily
1131 FLAGS is a bitmask consisting of the following flags:
1133 2: The function has a definition.
1134 4: The function is a friend.
1136 The TEMPLATE_COUNT is the number of references to qualifying
1137 template classes that appeared in the name of the function. For
1140 template <class T> struct S { void f(); };
1143 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1144 classes are not counted in the TEMPLATE_COUNT, so that in
1146 template <class T> struct S {};
1147 template <> struct S<int> { void f(); }
1148 template <> void S<int>::f();
1150 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1151 illegal; there should be no template <>.)
1153 If the function is a specialization, it is marked as such via
1154 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1155 is set up correctly, and it is added to the list of specializations
1156 for that template. */
1159 check_explicit_specialization (declarator, decl, template_count, flags)
1165 int have_def = flags & 2;
1166 int is_friend = flags & 4;
1167 int specialization = 0;
1168 int explicit_instantiation = 0;
1169 int member_specialization = 0;
1170 tree ctype = DECL_CLASS_CONTEXT (decl);
1171 tree dname = DECL_NAME (decl);
1174 tsk = current_tmpl_spec_kind (template_count);
1179 if (processing_specialization)
1182 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1184 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1187 /* This could be something like:
1189 template <class T> void f(T);
1190 class S { friend void f<>(int); } */
1194 /* This case handles bogus declarations like template <>
1195 template <class T> void f<int>(); */
1197 cp_error ("template-id `%D' in declaration of primary template",
1204 case tsk_invalid_member_spec:
1205 /* The error has already been reported in
1206 check_specialization_scope. */
1207 return error_mark_node;
1209 case tsk_invalid_expl_inst:
1210 cp_error ("template parameter list used in explicit instantiation");
1216 cp_error ("definition provided for explicit instantiation");
1218 explicit_instantiation = 1;
1221 case tsk_excessive_parms:
1222 cp_error ("too many template parameter lists in declaration of `%D'",
1224 return error_mark_node;
1228 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1230 member_specialization = 1;
1235 case tsk_insufficient_parms:
1236 if (template_header_count)
1238 cp_error("too few template parameter lists in declaration of `%D'",
1242 else if (ctype != NULL_TREE
1243 && !TYPE_BEING_DEFINED (ctype)
1244 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1247 /* For backwards compatibility, we accept:
1249 template <class T> struct S { void f(); };
1250 void S<int>::f() {} // Missing template <>
1252 That used to be legal C++. */
1255 ("explicit specialization not preceded by `template <>'");
1257 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1262 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1264 /* This case handles bogus declarations like template <>
1265 template <class T> void f<int>(); */
1267 cp_error ("template-id `%D' in declaration of primary template",
1272 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1273 /* This is a specialization of a member template, without
1274 specialization the containing class. Something like:
1276 template <class T> struct S {
1277 template <class U> void f (U);
1279 template <> template <class U> void S<int>::f(U) {}
1281 That's a specialization -- but of the entire template. */
1286 my_friendly_abort (20000309);
1289 if (specialization || member_specialization)
1291 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1292 for (; t; t = TREE_CHAIN (t))
1293 if (TREE_PURPOSE (t))
1296 ("default argument specified in explicit specialization");
1299 if (current_lang_name == lang_name_c)
1300 cp_error ("template specialization with C linkage");
1303 if (specialization || member_specialization || explicit_instantiation)
1305 tree tmpl = NULL_TREE;
1306 tree targs = NULL_TREE;
1308 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1309 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1313 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE,
1316 fns = IDENTIFIER_NAMESPACE_VALUE (dname);
1321 lookup_template_function (fns, NULL_TREE);
1324 if (declarator == error_mark_node)
1325 return error_mark_node;
1327 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1329 if (!explicit_instantiation)
1330 /* A specialization in class scope. This is illegal,
1331 but the error will already have been flagged by
1332 check_specialization_scope. */
1333 return error_mark_node;
1336 /* It's not legal to write an explicit instantiation in
1339 class C { template void f(); }
1341 This case is caught by the parser. However, on
1344 template class C { void f(); };
1346 (which is illegal) we can get here. The error will be
1353 else if (TREE_CODE (TREE_OPERAND (declarator, 0)) == LOOKUP_EXPR)
1355 /* A friend declaration. We can't do much, because we don't
1356 know what this resolves to, yet. */
1357 my_friendly_assert (is_friend != 0, 0);
1358 my_friendly_assert (!explicit_instantiation, 0);
1359 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1362 else if (ctype != NULL_TREE
1363 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1366 /* Find the list of functions in ctype that have the same
1367 name as the declared function. */
1368 tree name = TREE_OPERAND (declarator, 0);
1369 tree fns = NULL_TREE;
1372 if (name == constructor_name (ctype)
1373 || name == constructor_name_full (ctype))
1375 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1377 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1378 : !TYPE_HAS_DESTRUCTOR (ctype))
1380 /* From [temp.expl.spec]:
1382 If such an explicit specialization for the member
1383 of a class template names an implicitly-declared
1384 special member function (clause _special_), the
1385 program is ill-formed.
1387 Similar language is found in [temp.explicit]. */
1388 cp_error ("specialization of implicitly-declared special member function");
1389 return error_mark_node;
1392 name = is_constructor ? ctor_identifier : dtor_identifier;
1395 if (!IDENTIFIER_TYPENAME_P (name))
1397 idx = lookup_fnfields_1 (ctype, name);
1399 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1405 /* For a type-conversion operator, we cannot do a
1406 name-based lookup. We might be looking for `operator
1407 int' which will be a specialization of `operator T'.
1408 So, we find *all* the conversion operators, and then
1409 select from them. */
1412 methods = CLASSTYPE_METHOD_VEC (ctype);
1414 for (idx = 2; idx < TREE_VEC_LENGTH (methods); ++idx)
1416 tree ovl = TREE_VEC_ELT (methods, idx);
1418 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1419 /* There are no more conversion functions. */
1422 /* Glue all these conversion functions together
1423 with those we already have. */
1424 for (; ovl; ovl = OVL_NEXT (ovl))
1425 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1429 if (fns == NULL_TREE)
1431 cp_error ("no member function `%D' declared in `%T'",
1433 return error_mark_node;
1436 TREE_OPERAND (declarator, 0) = fns;
1439 /* Figure out what exactly is being specialized at this point.
1440 Note that for an explicit instantiation, even one for a
1441 member function, we cannot tell apriori whether the
1442 instantiation is for a member template, or just a member
1443 function of a template class. Even if a member template is
1444 being instantiated, the member template arguments may be
1445 elided if they can be deduced from the rest of the
1447 tmpl = determine_specialization (declarator, decl,
1449 member_specialization);
1451 if (!tmpl || tmpl == error_mark_node)
1452 /* We couldn't figure out what this declaration was
1454 return error_mark_node;
1457 tree gen_tmpl = most_general_template (tmpl);
1459 if (explicit_instantiation)
1461 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1462 is done by do_decl_instantiation later. */
1464 int arg_depth = TMPL_ARGS_DEPTH (targs);
1465 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1467 if (arg_depth > parm_depth)
1469 /* If TMPL is not the most general template (for
1470 example, if TMPL is a friend template that is
1471 injected into namespace scope), then there will
1472 be too many levels fo TARGS. Remove some of them
1477 new_targs = make_tree_vec (parm_depth);
1478 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1479 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1480 = TREE_VEC_ELT (targs, i);
1484 return instantiate_template (tmpl, targs);
1487 /* If this is both a template specialization, then it's a
1488 specialization of a member template of a template class.
1489 In that case we want to return the TEMPLATE_DECL, not the
1490 specialization of it. */
1491 if (tsk == tsk_template)
1493 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1497 /* If we though that the DECL was a member function, but it
1498 turns out to be specializing a static member function,
1499 make DECL a static member function as well. */
1500 if (DECL_STATIC_FUNCTION_P (tmpl)
1501 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1503 revert_static_member_fn (decl);
1504 last_function_parms = TREE_CHAIN (last_function_parms);
1507 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1508 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1510 /* Mangle the function name appropriately. Note that we do
1511 not mangle specializations of non-template member
1512 functions of template classes, e.g. with
1514 template <class T> struct S { void f(); }
1516 and given the specialization
1518 template <> void S<int>::f() {}
1520 we do not mangle S<int>::f() here. That's because it's
1521 just an ordinary member function and doesn't need special
1522 treatment. We do this here so that the ordinary,
1523 non-template, name-mangling algorithm will not be used
1525 if ((is_member_template (tmpl) || ctype == NULL_TREE)
1526 && name_mangling_version >= 1)
1527 set_mangled_name_for_template_decl (decl);
1529 if (is_friend && !have_def)
1530 /* This is not really a declaration of a specialization.
1531 It's just the name of an instantiation. But, it's not
1532 a request for an instantiation, either. */
1533 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1535 /* Register this specialization so that we can find it
1537 decl = register_specialization (decl, gen_tmpl, targs);
1544 /* TYPE is being declared. Verify that the use of template headers
1545 and such is reasonable. Issue error messages if not. */
1548 maybe_check_template_type (type)
1551 if (template_header_count)
1553 /* We are in the scope of some `template <...>' header. */
1556 = template_class_depth_real (TYPE_CONTEXT (type),
1557 /*count_specializations=*/1);
1559 if (template_header_count <= context_depth)
1560 /* This is OK; the template headers are for the context. We
1561 are actually too lenient here; like
1562 check_explicit_specialization we should consider the number
1563 of template types included in the actual declaration. For
1566 template <class T> struct S {
1567 template <class U> template <class V>
1573 template <class T> struct S {
1574 template <class U> struct I;
1577 template <class T> template <class U.
1582 else if (template_header_count > context_depth + 1)
1583 /* There are two many template parameter lists. */
1584 cp_error ("too many template parameter lists in declaration of `%T'", type);
1588 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1589 parameters. These are represented in the same format used for
1590 DECL_TEMPLATE_PARMS. */
1592 int comp_template_parms (parms1, parms2)
1599 if (parms1 == parms2)
1602 for (p1 = parms1, p2 = parms2;
1603 p1 != NULL_TREE && p2 != NULL_TREE;
1604 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1606 tree t1 = TREE_VALUE (p1);
1607 tree t2 = TREE_VALUE (p2);
1610 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1611 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1613 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1616 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1618 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1619 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1621 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1624 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1626 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1631 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1632 /* One set of parameters has more parameters lists than the
1639 /* Complain if DECL shadows a template parameter.
1641 [temp.local]: A template-parameter shall not be redeclared within its
1642 scope (including nested scopes). */
1645 check_template_shadow (decl)
1650 /* If we're not in a template, we can't possibly shadow a template
1652 if (!current_template_parms)
1655 /* Figure out what we're shadowing. */
1656 if (TREE_CODE (decl) == OVERLOAD)
1657 decl = OVL_CURRENT (decl);
1658 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1660 /* If there's no previous binding for this name, we're not shadowing
1661 anything, let alone a template parameter. */
1665 /* If we're not shadowing a template parameter, we're done. Note
1666 that OLDDECL might be an OVERLOAD (or perhaps even an
1667 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1669 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
1672 /* We check for decl != olddecl to avoid bogus errors for using a
1673 name inside a class. We check TPFI to avoid duplicate errors for
1674 inline member templates. */
1676 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1679 cp_error_at ("declaration of `%#D'", decl);
1680 cp_error_at (" shadows template parm `%#D'", olddecl);
1683 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1684 ORIG_LEVEL, DECL, and TYPE. */
1687 build_template_parm_index (index, level, orig_level, decl, type)
1694 tree t = make_node (TEMPLATE_PARM_INDEX);
1695 TEMPLATE_PARM_IDX (t) = index;
1696 TEMPLATE_PARM_LEVEL (t) = level;
1697 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1698 TEMPLATE_PARM_DECL (t) = decl;
1699 TREE_TYPE (t) = type;
1704 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1705 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1706 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1707 new one is created. */
1710 reduce_template_parm_level (index, type, levels)
1715 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
1716 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
1717 != TEMPLATE_PARM_LEVEL (index) - levels))
1720 = build_decl (TREE_CODE (TEMPLATE_PARM_DECL (index)),
1721 DECL_NAME (TEMPLATE_PARM_DECL (index)),
1724 = build_template_parm_index (TEMPLATE_PARM_IDX (index),
1725 TEMPLATE_PARM_LEVEL (index) - levels,
1726 TEMPLATE_PARM_ORIG_LEVEL (index),
1728 TEMPLATE_PARM_DESCENDANTS (index) = t;
1730 /* Template template parameters need this. */
1731 DECL_TEMPLATE_PARMS (decl)
1732 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
1735 return TEMPLATE_PARM_DESCENDANTS (index);
1738 /* Process information from new template parameter NEXT and append it to the
1739 LIST being built. */
1742 process_template_parm (list, next)
1751 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
1752 defval = TREE_PURPOSE (parm);
1753 parm = TREE_VALUE (parm);
1754 is_type = TREE_PURPOSE (parm) == class_type_node;
1758 tree p = TREE_VALUE (tree_last (list));
1760 if (TREE_CODE (p) == TYPE_DECL)
1761 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
1762 else if (TREE_CODE (p) == TEMPLATE_DECL)
1763 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (DECL_TEMPLATE_RESULT (p)));
1765 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
1773 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
1774 /* is a const-param */
1775 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
1776 PARM, 0, NULL_TREE);
1780 The top-level cv-qualifiers on the template-parameter are
1781 ignored when determining its type. */
1782 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
1784 /* A template parameter is not modifiable. */
1785 TREE_READONLY (parm) = 1;
1786 if (IS_AGGR_TYPE (TREE_TYPE (parm))
1787 && TREE_CODE (TREE_TYPE (parm)) != TEMPLATE_TYPE_PARM
1788 && TREE_CODE (TREE_TYPE (parm)) != TYPENAME_TYPE)
1790 cp_error ("`%#T' is not a valid type for a template constant parameter",
1792 if (DECL_NAME (parm) == NULL_TREE)
1793 error (" a template type parameter must begin with `class' or `typename'");
1794 TREE_TYPE (parm) = void_type_node;
1797 && (TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE
1798 || TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE))
1799 cp_pedwarn ("`%T' is not a valid type for a template constant parameter",
1801 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
1802 DECL_INITIAL (parm) = DECL_INITIAL (decl)
1803 = build_template_parm_index (idx, processing_template_decl,
1804 processing_template_decl,
1805 decl, TREE_TYPE (parm));
1810 parm = TREE_VALUE (parm);
1812 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
1814 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
1815 /* This is for distinguishing between real templates and template
1816 template parameters */
1817 TREE_TYPE (parm) = t;
1818 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
1823 t = make_aggr_type (TEMPLATE_TYPE_PARM);
1824 /* parm is either IDENTIFIER_NODE or NULL_TREE */
1825 decl = build_decl (TYPE_DECL, parm, t);
1828 TYPE_NAME (t) = decl;
1829 TYPE_STUB_DECL (t) = decl;
1831 TEMPLATE_TYPE_PARM_INDEX (t)
1832 = build_template_parm_index (idx, processing_template_decl,
1833 processing_template_decl,
1834 decl, TREE_TYPE (parm));
1836 SET_DECL_ARTIFICIAL (decl);
1837 SET_DECL_TEMPLATE_PARM_P (decl);
1839 parm = build_tree_list (defval, parm);
1840 return chainon (list, parm);
1843 /* The end of a template parameter list has been reached. Process the
1844 tree list into a parameter vector, converting each parameter into a more
1845 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
1849 end_template_parm_list (parms)
1854 tree saved_parmlist = make_tree_vec (list_length (parms));
1856 current_template_parms
1857 = tree_cons (build_int_2 (0, processing_template_decl),
1858 saved_parmlist, current_template_parms);
1860 for (parm = parms, nparms = 0;
1862 parm = TREE_CHAIN (parm), nparms++)
1863 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
1865 --processing_template_parmlist;
1867 return saved_parmlist;
1870 /* end_template_decl is called after a template declaration is seen. */
1873 end_template_decl ()
1875 reset_specialization ();
1877 if (! processing_template_decl)
1880 /* This matches the pushlevel in begin_template_parm_list. */
1883 --processing_template_decl;
1884 current_template_parms = TREE_CHAIN (current_template_parms);
1887 /* Given a template argument vector containing the template PARMS.
1888 The innermost PARMS are given first. */
1891 current_template_args ()
1894 tree args = NULL_TREE;
1895 int length = TMPL_PARMS_DEPTH (current_template_parms);
1898 /* If there is only one level of template parameters, we do not
1899 create a TREE_VEC of TREE_VECs. Instead, we return a single
1900 TREE_VEC containing the arguments. */
1902 args = make_tree_vec (length);
1904 for (header = current_template_parms; header; header = TREE_CHAIN (header))
1906 tree a = copy_node (TREE_VALUE (header));
1909 TREE_TYPE (a) = NULL_TREE;
1910 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
1912 tree t = TREE_VEC_ELT (a, i);
1914 /* T will be a list if we are called from within a
1915 begin/end_template_parm_list pair, but a vector directly
1916 if within a begin/end_member_template_processing pair. */
1917 if (TREE_CODE (t) == TREE_LIST)
1921 if (TREE_CODE (t) == TYPE_DECL
1922 || TREE_CODE (t) == TEMPLATE_DECL)
1925 t = DECL_INITIAL (t);
1926 TREE_VEC_ELT (a, i) = t;
1931 TREE_VEC_ELT (args, --l) = a;
1939 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
1940 template PARMS. Used by push_template_decl below. */
1943 build_template_decl (decl, parms)
1947 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
1948 DECL_TEMPLATE_PARMS (tmpl) = parms;
1949 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
1950 if (DECL_LANG_SPECIFIC (decl))
1952 DECL_VIRTUAL_CONTEXT (tmpl) = DECL_VIRTUAL_CONTEXT (decl);
1953 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
1954 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
1955 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
1961 struct template_parm_data
1963 /* The level of the template parameters we are currently
1967 /* The index of the specialization argument we are currently
1971 /* An array whose size is the number of template parameters. The
1972 elements are non-zero if the parameter has been used in any one
1973 of the arguments processed so far. */
1976 /* An array whose size is the number of template arguments. The
1977 elements are non-zero if the argument makes use of template
1978 parameters of this level. */
1979 int* arg_uses_template_parms;
1982 /* Subroutine of push_template_decl used to see if each template
1983 parameter in a partial specialization is used in the explicit
1984 argument list. If T is of the LEVEL given in DATA (which is
1985 treated as a template_parm_data*), then DATA->PARMS is marked
1989 mark_template_parm (t, data)
1995 struct template_parm_data* tpd = (struct template_parm_data*) data;
1997 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
1999 level = TEMPLATE_PARM_LEVEL (t);
2000 idx = TEMPLATE_PARM_IDX (t);
2004 level = TEMPLATE_TYPE_LEVEL (t);
2005 idx = TEMPLATE_TYPE_IDX (t);
2008 if (level == tpd->level)
2010 tpd->parms[idx] = 1;
2011 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2014 /* Return zero so that for_each_template_parm will continue the
2015 traversal of the tree; we want to mark *every* template parm. */
2019 /* Process the partial specialization DECL. */
2022 process_partial_specialization (decl)
2025 tree type = TREE_TYPE (decl);
2026 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2027 tree specargs = CLASSTYPE_TI_ARGS (type);
2028 tree inner_args = innermost_args (specargs);
2029 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2030 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2031 int nargs = TREE_VEC_LENGTH (inner_args);
2032 int ntparms = TREE_VEC_LENGTH (inner_parms);
2034 int did_error_intro = 0;
2035 struct template_parm_data tpd;
2036 struct template_parm_data tpd2;
2038 /* We check that each of the template parameters given in the
2039 partial specialization is used in the argument list to the
2040 specialization. For example:
2042 template <class T> struct S;
2043 template <class T> struct S<T*>;
2045 The second declaration is OK because `T*' uses the template
2046 parameter T, whereas
2048 template <class T> struct S<int>;
2050 is no good. Even trickier is:
2061 The S2<T> declaration is actually illegal; it is a
2062 full-specialization. Of course,
2065 struct S2<T (*)(U)>;
2067 or some such would have been OK. */
2068 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2069 tpd.parms = alloca (sizeof (int) * ntparms);
2070 bzero ((PTR) tpd.parms, sizeof (int) * ntparms);
2072 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2073 bzero ((PTR) tpd.arg_uses_template_parms, sizeof (int) * nargs);
2074 for (i = 0; i < nargs; ++i)
2076 tpd.current_arg = i;
2077 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2078 &mark_template_parm,
2081 for (i = 0; i < ntparms; ++i)
2082 if (tpd.parms[i] == 0)
2084 /* One of the template parms was not used in the
2086 if (!did_error_intro)
2088 cp_error ("template parameters not used in partial specialization:");
2089 did_error_intro = 1;
2093 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2096 /* [temp.class.spec]
2098 The argument list of the specialization shall not be identical to
2099 the implicit argument list of the primary template. */
2100 if (comp_template_args (inner_args,
2101 innermost_args (CLASSTYPE_TI_ARGS (TREE_TYPE
2103 cp_error ("partial specialization `%T' does not specialize any template arguments", type);
2105 /* [temp.class.spec]
2107 A partially specialized non-type argument expression shall not
2108 involve template parameters of the partial specialization except
2109 when the argument expression is a simple identifier.
2111 The type of a template parameter corresponding to a specialized
2112 non-type argument shall not be dependent on a parameter of the
2114 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2116 for (i = 0; i < nargs; ++i)
2118 tree arg = TREE_VEC_ELT (inner_args, i);
2119 if (/* These first two lines are the `non-type' bit. */
2121 && TREE_CODE (arg) != TEMPLATE_DECL
2122 /* This next line is the `argument expression is not just a
2123 simple identifier' condition and also the `specialized
2124 non-type argument' bit. */
2125 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2127 if (tpd.arg_uses_template_parms[i])
2128 cp_error ("template argument `%E' involves template parameter(s)", arg);
2131 /* Look at the corresponding template parameter,
2132 marking which template parameters its type depends
2135 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2140 /* We haven't yet initialized TPD2. Do so now. */
2141 tpd2.arg_uses_template_parms
2142 = (int*) alloca (sizeof (int) * nargs);
2143 /* The number of parameters here is the number in the
2144 main template, which, as checked in the assertion
2146 tpd2.parms = (int*) alloca (sizeof (int) * nargs);
2148 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2151 /* Mark the template parameters. But this time, we're
2152 looking for the template parameters of the main
2153 template, not in the specialization. */
2154 tpd2.current_arg = i;
2155 tpd2.arg_uses_template_parms[i] = 0;
2156 bzero ((PTR) tpd2.parms, sizeof (int) * nargs);
2157 for_each_template_parm (type,
2158 &mark_template_parm,
2161 if (tpd2.arg_uses_template_parms [i])
2163 /* The type depended on some template parameters.
2164 If they are fully specialized in the
2165 specialization, that's OK. */
2167 for (j = 0; j < nargs; ++j)
2168 if (tpd2.parms[j] != 0
2169 && tpd.arg_uses_template_parms [j])
2171 cp_error ("type `%T' of template argument `%E' depends on template parameter(s)",
2181 if (retrieve_specialization (maintmpl, specargs))
2182 /* We've already got this specialization. */
2185 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2186 = tree_cons (inner_args, inner_parms,
2187 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2188 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2192 /* Check that a template declaration's use of default arguments is not
2193 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2194 non-zero if DECL is the thing declared by a primary template.
2195 IS_PARTIAL is non-zero if DECL is a partial specialization. */
2198 check_default_tmpl_args (decl, parms, is_primary, is_partial)
2205 int last_level_to_check;
2210 A default template-argument shall not be specified in a
2211 function template declaration or a function template definition, nor
2212 in the template-parameter-list of the definition of a member of a
2215 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2216 /* You can't have a function template declaration in a local
2217 scope, nor you can you define a member of a class template in a
2221 if (current_class_type
2222 && !TYPE_BEING_DEFINED (current_class_type)
2223 && DECL_LANG_SPECIFIC (decl)
2224 /* If this is either a friend defined in the scope of the class
2225 or a member function. */
2226 && ((DECL_CONTEXT (decl)
2227 && same_type_p (DECL_CONTEXT (decl), current_class_type))
2228 || (DECL_FRIEND_CONTEXT (decl)
2229 && same_type_p (DECL_FRIEND_CONTEXT (decl),
2230 current_class_type)))
2231 /* And, if it was a member function, it really was defined in
2232 the scope of the class. */
2233 && (!DECL_FUNCTION_MEMBER_P (decl) || DECL_DEFINED_IN_CLASS_P (decl)))
2234 /* We already checked these parameters when the template was
2235 declared, so there's no need to do it again now. This function
2236 was defined in class scope, but we're processing it's body now
2237 that the class is complete. */
2242 If a template-parameter has a default template-argument, all
2243 subsequent template-parameters shall have a default
2244 template-argument supplied. */
2245 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2247 tree inner_parms = TREE_VALUE (parm_level);
2248 int ntparms = TREE_VEC_LENGTH (inner_parms);
2249 int seen_def_arg_p = 0;
2252 for (i = 0; i < ntparms; ++i)
2254 tree parm = TREE_VEC_ELT (inner_parms, i);
2255 if (TREE_PURPOSE (parm))
2257 else if (seen_def_arg_p)
2259 cp_error ("no default argument for `%D'", TREE_VALUE (parm));
2260 /* For better subsequent error-recovery, we indicate that
2261 there should have been a default argument. */
2262 TREE_PURPOSE (parm) = error_mark_node;
2267 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2268 /* For an ordinary class template, default template arguments are
2269 allowed at the innermost level, e.g.:
2270 template <class T = int>
2272 but, in a partial specialization, they're not allowed even
2273 there, as we have in [temp.class.spec]:
2275 The template parameter list of a specialization shall not
2276 contain default template argument values.
2278 So, for a partial specialization, or for a function template,
2279 we look at all of them. */
2282 /* But, for a primary class template that is not a partial
2283 specialization we look at all template parameters except the
2285 parms = TREE_CHAIN (parms);
2287 /* Figure out what error message to issue. */
2288 if (TREE_CODE (decl) == FUNCTION_DECL)
2289 msg = "default argument for template parameter in function template `%D'";
2290 else if (is_partial)
2291 msg = "default argument in partial specialization `%D'";
2293 msg = "default argument for template parameter for class enclosing `%D'";
2295 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2296 /* If we're inside a class definition, there's no need to
2297 examine the parameters to the class itself. On the one
2298 hand, they will be checked when the class is defined, and,
2299 on the other, default arguments are legal in things like:
2300 template <class T = double>
2301 struct S { template <class U> void f(U); };
2302 Here the default argument for `S' has no bearing on the
2303 declaration of `f'. */
2304 last_level_to_check = template_class_depth (current_class_type) + 1;
2306 /* Check everything. */
2307 last_level_to_check = 0;
2309 for (parm_level = parms;
2310 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2311 parm_level = TREE_CHAIN (parm_level))
2313 tree inner_parms = TREE_VALUE (parm_level);
2317 ntparms = TREE_VEC_LENGTH (inner_parms);
2318 for (i = 0; i < ntparms; ++i)
2319 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2323 cp_error (msg, decl);
2327 /* Clear out the default argument so that we are not
2329 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2332 /* At this point, if we're still interested in issuing messages,
2333 they must apply to classes surrounding the object declared. */
2335 msg = "default argument for template parameter for class enclosing `%D'";
2339 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2340 parameters given by current_template_args, or reuses a
2341 previously existing one, if appropriate. Returns the DECL, or an
2342 equivalent one, if it is replaced via a call to duplicate_decls.
2344 If IS_FRIEND is non-zero, DECL is a friend declaration. */
2347 push_template_decl_real (decl, is_friend)
2357 int new_template_p = 0;
2359 /* See if this is a partial specialization. */
2360 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2361 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2362 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2364 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2367 /* For a friend, we want the context of the friend function, not
2368 the type of which it is a friend. */
2369 ctx = DECL_CONTEXT (decl);
2370 else if (CP_DECL_CONTEXT (decl)
2371 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2372 /* In the case of a virtual function, we want the class in which
2374 ctx = CP_DECL_CONTEXT (decl);
2376 /* Otherwise, if we're currently definining some class, the DECL
2377 is assumed to be a member of the class. */
2378 ctx = current_scope ();
2380 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2383 if (!DECL_CONTEXT (decl))
2384 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2386 /* See if this is a primary template. */
2387 primary = template_parm_scope_p ();
2391 if (current_lang_name == lang_name_c)
2392 cp_error ("template with C linkage");
2393 else if (TREE_CODE (decl) == TYPE_DECL
2394 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2395 cp_error ("template class without a name");
2396 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2397 && CLASS_TYPE_P (TREE_TYPE (decl)))
2398 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2399 || TREE_CODE (decl) == FUNCTION_DECL)
2402 cp_error ("template declaration of `%#D'", decl);
2405 /* Check to see that the rules regarding the use of default
2406 arguments are not being violated. */
2407 check_default_tmpl_args (decl, current_template_parms,
2408 primary, is_partial);
2411 return process_partial_specialization (decl);
2413 args = current_template_args ();
2416 || TREE_CODE (ctx) == FUNCTION_DECL
2417 || TYPE_BEING_DEFINED (ctx)
2418 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2420 if (DECL_LANG_SPECIFIC (decl)
2421 && DECL_TEMPLATE_INFO (decl)
2422 && DECL_TI_TEMPLATE (decl))
2423 tmpl = DECL_TI_TEMPLATE (decl);
2424 /* If DECL is a TYPE_DECL for a class-template, then there won't
2425 be DECL_LANG_SPECIFIC. The information equivalent to
2426 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2427 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2428 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2429 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2431 /* Since a template declaration already existed for this
2432 class-type, we must be redeclaring it here. Make sure
2433 that the redeclaration is legal. */
2434 redeclare_class_template (TREE_TYPE (decl),
2435 current_template_parms);
2436 /* We don't need to create a new TEMPLATE_DECL; just use the
2437 one we already had. */
2438 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2442 tmpl = build_template_decl (decl, current_template_parms);
2445 if (DECL_LANG_SPECIFIC (decl)
2446 && DECL_TEMPLATE_SPECIALIZATION (decl))
2448 /* A specialization of a member template of a template
2450 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2451 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2452 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2458 tree a, t, current, parms;
2461 if (TREE_CODE (decl) == TYPE_DECL)
2463 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2464 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2465 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2466 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2467 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2470 cp_error ("`%D' does not declare a template type", decl);
2474 else if (! DECL_TEMPLATE_INFO (decl))
2476 cp_error ("template definition of non-template `%#D'", decl);
2480 tmpl = DECL_TI_TEMPLATE (decl);
2482 if (is_member_template (tmpl)
2483 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2484 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2485 && DECL_TEMPLATE_SPECIALIZATION (decl))
2489 /* The declaration is a specialization of a member
2490 template, declared outside the class. Therefore, the
2491 innermost template arguments will be NULL, so we
2492 replace them with the arguments determined by the
2493 earlier call to check_explicit_specialization. */
2494 args = DECL_TI_ARGS (decl);
2497 = build_template_decl (decl, current_template_parms);
2498 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2499 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2500 DECL_TI_TEMPLATE (decl) = new_tmpl;
2501 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2502 DECL_TEMPLATE_INFO (new_tmpl)
2503 = tree_cons (tmpl, args, NULL_TREE);
2505 register_specialization (new_tmpl, tmpl, args);
2509 /* Make sure the template headers we got make sense. */
2511 parms = DECL_TEMPLATE_PARMS (tmpl);
2512 i = TMPL_PARMS_DEPTH (parms);
2513 if (TMPL_ARGS_DEPTH (args) != i)
2515 cp_error ("expected %d levels of template parms for `%#D', got %d",
2516 i, decl, TMPL_ARGS_DEPTH (args));
2519 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2521 a = TMPL_ARGS_LEVEL (args, i);
2522 t = INNERMOST_TEMPLATE_PARMS (parms);
2524 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2526 if (current == decl)
2527 cp_error ("got %d template parameters for `%#D'",
2528 TREE_VEC_LENGTH (a), decl);
2530 cp_error ("got %d template parameters for `%#T'",
2531 TREE_VEC_LENGTH (a), current);
2532 cp_error (" but %d required", TREE_VEC_LENGTH (t));
2535 /* Perhaps we should also check that the parms are used in the
2536 appropriate qualifying scopes in the declarator? */
2538 if (current == decl)
2541 current = TYPE_CONTEXT (current);
2545 DECL_TEMPLATE_RESULT (tmpl) = decl;
2546 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2548 /* Push template declarations for global functions and types. Note
2549 that we do not try to push a global template friend declared in a
2550 template class; such a thing may well depend on the template
2551 parameters of the class. */
2552 if (new_template_p && !ctx
2553 && !(is_friend && template_class_depth (current_class_type) > 0))
2554 tmpl = pushdecl_namespace_level (tmpl);
2557 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2559 info = tree_cons (tmpl, args, NULL_TREE);
2561 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2563 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2564 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2565 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE)
2566 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2568 else if (DECL_LANG_SPECIFIC (decl))
2569 DECL_TEMPLATE_INFO (decl) = info;
2571 return DECL_TEMPLATE_RESULT (tmpl);
2575 push_template_decl (decl)
2578 return push_template_decl_real (decl, 0);
2581 /* Called when a class template TYPE is redeclared with the indicated
2582 template PARMS, e.g.:
2584 template <class T> struct S;
2585 template <class T> struct S {}; */
2588 redeclare_class_template (type, parms)
2596 if (!TYPE_TEMPLATE_INFO (type))
2598 cp_error ("`%T' is not a template type", type);
2602 tmpl = TYPE_TI_TEMPLATE (type);
2603 if (!PRIMARY_TEMPLATE_P (tmpl))
2604 /* The type is nested in some template class. Nothing to worry
2605 about here; there are no new template parameters for the nested
2609 parms = INNERMOST_TEMPLATE_PARMS (parms);
2610 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2612 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2614 cp_error_at ("previous declaration `%D'", tmpl);
2615 cp_error ("used %d template parameter%s instead of %d",
2616 TREE_VEC_LENGTH (tmpl_parms),
2617 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2618 TREE_VEC_LENGTH (parms));
2622 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2624 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2625 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2626 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2627 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2629 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2631 cp_error_at ("template parameter `%#D'", tmpl_parm);
2632 cp_error ("redeclared here as `%#D'", parm);
2636 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2638 /* We have in [temp.param]:
2640 A template-parameter may not be given default arguments
2641 by two different declarations in the same scope. */
2642 cp_error ("redefinition of default argument for `%#D'", parm);
2643 cp_error_at (" original definition appeared here", tmpl_parm);
2647 if (parm_default != NULL_TREE)
2648 /* Update the previous template parameters (which are the ones
2649 that will really count) with the new default value. */
2650 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2651 else if (tmpl_default != NULL_TREE)
2652 /* Update the new parameters, too; they'll be used as the
2653 parameters for any members. */
2654 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2658 /* Attempt to convert the non-type template parameter EXPR to the
2659 indicated TYPE. If the conversion is successful, return the
2660 converted value. If the conversion is unsuccesful, return
2661 NULL_TREE if we issued an error message, or error_mark_node if we
2662 did not. We issue error messages for out-and-out bad template
2663 parameters, but not simply because the conversion failed, since we
2664 might be just trying to do argument deduction. By the time this
2665 function is called, neither TYPE nor EXPR may make use of template
2669 convert_nontype_argument (type, expr)
2673 tree expr_type = TREE_TYPE (expr);
2675 /* A template-argument for a non-type, non-template
2676 template-parameter shall be one of:
2678 --an integral constant-expression of integral or enumeration
2681 --the name of a non-type template-parameter; or
2683 --the name of an object or function with external linkage,
2684 including function templates and function template-ids but
2685 excluding non-static class members, expressed as id-expression;
2688 --the address of an object or function with external linkage,
2689 including function templates and function template-ids but
2690 excluding non-static class members, expressed as & id-expression
2691 where the & is optional if the name refers to a function or
2694 --a pointer to member expressed as described in _expr.unary.op_. */
2696 /* An integral constant-expression can include const variables or
2697 enumerators. Simplify things by folding them to their values,
2698 unless we're about to bind the declaration to a reference
2700 if (INTEGRAL_TYPE_P (expr_type) && TREE_READONLY_DECL_P (expr)
2701 && TREE_CODE (type) != REFERENCE_TYPE)
2702 expr = decl_constant_value (expr);
2704 if (is_overloaded_fn (expr))
2705 /* OK for now. We'll check that it has external linkage later.
2706 Check this first since if expr_type is the unknown_type_node
2707 we would otherwise complain below. */
2709 else if (TYPE_PTRMEM_P (expr_type)
2710 || TYPE_PTRMEMFUNC_P (expr_type))
2712 if (TREE_CODE (expr) != PTRMEM_CST)
2715 else if (TYPE_PTR_P (expr_type)
2716 || TYPE_PTRMEM_P (expr_type)
2717 || TREE_CODE (expr_type) == ARRAY_TYPE
2718 || TREE_CODE (type) == REFERENCE_TYPE
2719 /* If expr is the address of an overloaded function, we
2720 will get the unknown_type_node at this point. */
2721 || expr_type == unknown_type_node)
2727 if (TREE_CODE (type) == REFERENCE_TYPE
2728 || TREE_CODE (expr_type) == ARRAY_TYPE)
2732 if (TREE_CODE (e) != ADDR_EXPR)
2735 cp_error ("`%E' is not a valid template argument", expr);
2736 if (TYPE_PTR_P (expr_type))
2738 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
2739 cp_error ("it must be the address of a function with external linkage");
2741 cp_error ("it must be the address of an object with external linkage");
2743 else if (TYPE_PTRMEM_P (expr_type)
2744 || TYPE_PTRMEMFUNC_P (expr_type))
2745 cp_error ("it must be a pointer-to-member of the form `&X::Y'");
2750 referent = TREE_OPERAND (e, 0);
2751 STRIP_NOPS (referent);
2754 if (TREE_CODE (referent) == STRING_CST)
2756 cp_error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
2761 if (is_overloaded_fn (referent))
2762 /* We'll check that it has external linkage later. */
2764 else if (TREE_CODE (referent) != VAR_DECL)
2766 else if (!TREE_PUBLIC (referent))
2768 cp_error ("address of non-extern `%E' cannot be used as template argument", referent);
2769 return error_mark_node;
2772 else if (INTEGRAL_TYPE_P (expr_type)
2773 || TYPE_PTRMEM_P (expr_type)
2774 || TYPE_PTRMEMFUNC_P (expr_type)
2775 /* The next two are g++ extensions. */
2776 || TREE_CODE (expr_type) == REAL_TYPE
2777 || TREE_CODE (expr_type) == COMPLEX_TYPE)
2779 if (! TREE_CONSTANT (expr))
2782 cp_error ("non-constant `%E' cannot be used as template argument",
2789 cp_error ("object `%E' cannot be used as template argument", expr);
2793 switch (TREE_CODE (type))
2798 /* For a non-type template-parameter of integral or enumeration
2799 type, integral promotions (_conv.prom_) and integral
2800 conversions (_conv.integral_) are applied. */
2801 if (!INTEGRAL_TYPE_P (expr_type))
2802 return error_mark_node;
2804 /* It's safe to call digest_init in this case; we know we're
2805 just converting one integral constant expression to another. */
2806 expr = digest_init (type, expr, (tree*) 0);
2808 if (TREE_CODE (expr) != INTEGER_CST)
2809 /* Curiously, some TREE_CONSTANT integral expressions do not
2810 simplify to integer constants. For example, `3 % 0',
2811 remains a TRUNC_MOD_EXPR. */
2818 /* These are g++ extensions. */
2819 if (TREE_CODE (expr_type) != TREE_CODE (type))
2820 return error_mark_node;
2822 expr = digest_init (type, expr, (tree*) 0);
2824 if (TREE_CODE (expr) != REAL_CST)
2831 tree type_pointed_to = TREE_TYPE (type);
2833 if (TYPE_PTRMEM_P (type))
2837 /* For a non-type template-parameter of type pointer to data
2838 member, qualification conversions (_conv.qual_) are
2840 e = perform_qualification_conversions (type, expr);
2841 if (TREE_CODE (e) == NOP_EXPR)
2842 /* The call to perform_qualification_conversions will
2843 insert a NOP_EXPR over EXPR to do express conversion,
2844 if necessary. But, that will confuse us if we use
2845 this (converted) template parameter to instantiate
2846 another template; then the thing will not look like a
2847 valid template argument. So, just make a new
2848 constant, of the appropriate type. */
2849 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
2852 else if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
2854 /* For a non-type template-parameter of type pointer to
2855 function, only the function-to-pointer conversion
2856 (_conv.func_) is applied. If the template-argument
2857 represents a set of overloaded functions (or a pointer to
2858 such), the matching function is selected from the set
2863 if (TREE_CODE (expr) == ADDR_EXPR)
2864 fns = TREE_OPERAND (expr, 0);
2868 fn = instantiate_type (type_pointed_to, fns, 0);
2870 if (fn == error_mark_node)
2871 return error_mark_node;
2873 if (!TREE_PUBLIC (fn))
2875 if (really_overloaded_fn (fns))
2876 return error_mark_node;
2881 expr = build_unary_op (ADDR_EXPR, fn, 0);
2883 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
2889 /* For a non-type template-parameter of type pointer to
2890 object, qualification conversions (_conv.qual_) and the
2891 array-to-pointer conversion (_conv.array_) are applied.
2892 [Note: In particular, neither the null pointer conversion
2893 (_conv.ptr_) nor the derived-to-base conversion
2894 (_conv.ptr_) are applied. Although 0 is a valid
2895 template-argument for a non-type template-parameter of
2896 integral type, it is not a valid template-argument for a
2897 non-type template-parameter of pointer type.]
2899 The call to decay_conversion performs the
2900 array-to-pointer conversion, if appropriate. */
2901 expr = decay_conversion (expr);
2903 if (expr == error_mark_node)
2904 return error_mark_node;
2906 return perform_qualification_conversions (type, expr);
2911 case REFERENCE_TYPE:
2913 tree type_referred_to = TREE_TYPE (type);
2915 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
2917 /* For a non-type template-parameter of type reference to
2918 function, no conversions apply. If the
2919 template-argument represents a set of overloaded
2920 functions, the matching function is selected from the
2921 set (_over.over_). */
2925 fn = instantiate_type (type_referred_to, fns, 0);
2927 if (fn == error_mark_node)
2928 return error_mark_node;
2930 if (!TREE_PUBLIC (fn))
2932 if (really_overloaded_fn (fns))
2933 /* Don't issue an error here; we might get a different
2934 function if the overloading had worked out
2936 return error_mark_node;
2941 my_friendly_assert (same_type_p (type_referred_to,
2949 /* For a non-type template-parameter of type reference to
2950 object, no conversions apply. The type referred to by the
2951 reference may be more cv-qualified than the (otherwise
2952 identical) type of the template-argument. The
2953 template-parameter is bound directly to the
2954 template-argument, which must be an lvalue. */
2955 if ((TYPE_MAIN_VARIANT (expr_type)
2956 != TYPE_MAIN_VARIANT (type_referred_to))
2957 || !at_least_as_qualified_p (type_referred_to,
2959 || !real_lvalue_p (expr))
2960 return error_mark_node;
2969 if (!TYPE_PTRMEMFUNC_P (type))
2970 /* This handles templates like
2971 template<class T, T t> void f();
2972 when T is substituted with any class. The second template
2973 parameter becomes invalid and the template candidate is
2975 return error_mark_node;
2977 /* For a non-type template-parameter of type pointer to member
2978 function, no conversions apply. If the template-argument
2979 represents a set of overloaded member functions, the
2980 matching member function is selected from the set
2983 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
2984 expr_type != unknown_type_node)
2985 return error_mark_node;
2987 if (TREE_CODE (expr) == PTRMEM_CST)
2989 /* A ptr-to-member constant. */
2990 if (!same_type_p (type, expr_type))
2991 return error_mark_node;
2996 if (TREE_CODE (expr) != ADDR_EXPR)
2997 return error_mark_node;
2999 expr = instantiate_type (type, expr, 0);
3001 if (expr == error_mark_node)
3002 return error_mark_node;
3004 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3011 /* All non-type parameters must have one of these types. */
3012 my_friendly_abort (0);
3016 return error_mark_node;
3019 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3020 template template parameters. Both PARM_PARMS and ARG_PARMS are
3021 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3024 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3025 the case, then extra parameters must have default arguments.
3027 Consider the example:
3028 template <class T, class Allocator = allocator> class vector;
3029 template<template <class U> class TT> class C;
3031 C<vector> is a valid instantiation. PARM_PARMS for the above code
3032 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3033 T and Allocator) and OUTER_ARGS contains the argument that is used to
3034 substitute the TT parameter. */
3037 coerce_template_template_parms (parm_parms, arg_parms, complain,
3038 in_decl, outer_args)
3039 tree parm_parms, arg_parms;
3041 tree in_decl, outer_args;
3043 int nparms, nargs, i;
3046 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3047 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3049 nparms = TREE_VEC_LENGTH (parm_parms);
3050 nargs = TREE_VEC_LENGTH (arg_parms);
3052 /* The rule here is opposite of coerce_template_parms. */
3055 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3058 for (i = 0; i < nparms; ++i)
3060 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3061 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3063 if (arg == NULL_TREE || arg == error_mark_node
3064 || parm == NULL_TREE || parm == error_mark_node)
3067 if (TREE_CODE (arg) != TREE_CODE (parm))
3070 switch (TREE_CODE (parm))
3076 /* We encounter instantiations of templates like
3077 template <template <template <class> class> class TT>
3080 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3081 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3083 if (!coerce_template_template_parms (parmparm, argparm,
3091 /* The tsubst call is used to handle cases such as
3092 template <class T, template <T> class TT> class D;
3093 i.e. the parameter list of TT depends on earlier parameters. */
3094 if (!same_type_p (tsubst (TREE_TYPE (parm), outer_args,
3101 my_friendly_abort (0);
3107 /* Convert the indicated template ARG as necessary to match the
3108 indicated template PARM. Returns the converted ARG, or
3109 error_mark_node if the conversion was unsuccessful. Error messages
3110 are issued if COMPLAIN is non-zero. This conversion is for the Ith
3111 parameter in the parameter list. ARGS is the full set of template
3112 arguments deduced so far. */
3115 convert_template_argument (parm, arg, args, complain, i, in_decl)
3125 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3127 inner_args = innermost_args (args);
3129 if (TREE_CODE (arg) == TREE_LIST
3130 && TREE_TYPE (arg) != NULL_TREE
3131 && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
3133 /* The template argument was the name of some
3134 member function. That's usually
3135 illegal, but static members are OK. In any
3136 case, grab the underlying fields/functions
3137 and issue an error later if required. */
3138 arg = TREE_VALUE (arg);
3139 TREE_TYPE (arg) = unknown_type_node;
3142 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3143 requires_type = (TREE_CODE (parm) == TYPE_DECL
3144 || requires_tmpl_type);
3146 /* Check if it is a class template. If REQUIRES_TMPL_TYPE is true,
3147 we also accept implicitly created TYPE_DECL as a valid argument.
3148 This is necessary to handle the case where we pass a template name
3149 to a template template parameter in a scope where we've derived from
3150 in instantiation of that template, so the template name refers to that
3151 instantiation. We really ought to handle this better. */
3153 = ((TREE_CODE (arg) == TEMPLATE_DECL
3154 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3155 || (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3156 && !TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (arg))
3157 || (TREE_CODE (arg) == RECORD_TYPE
3158 && CLASSTYPE_TEMPLATE_INFO (arg)
3159 && TREE_CODE (TYPE_NAME (arg)) == TYPE_DECL
3160 && DECL_ARTIFICIAL (TYPE_NAME (arg))
3161 && requires_tmpl_type
3162 && is_base_of_enclosing_class (arg, current_class_type)));
3163 if (is_tmpl_type && TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
3164 arg = TYPE_STUB_DECL (arg);
3165 else if (is_tmpl_type && TREE_CODE (arg) == RECORD_TYPE)
3166 arg = CLASSTYPE_TI_TEMPLATE (arg);
3168 is_type = TYPE_P (arg) || is_tmpl_type;
3170 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3171 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3173 cp_pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3175 arg = make_typename_type (TREE_OPERAND (arg, 0),
3176 TREE_OPERAND (arg, 1),
3180 if (is_type != requires_type)
3186 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3189 cp_error (" expected a constant of type `%T', got `%T'",
3191 (is_tmpl_type ? DECL_NAME (arg) : arg));
3193 cp_error (" expected a type, got `%E'", arg);
3196 return error_mark_node;
3198 if (is_tmpl_type ^ requires_tmpl_type)
3200 if (in_decl && complain)
3202 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3205 cp_error (" expected a type, got `%T'", DECL_NAME (arg));
3207 cp_error (" expected a class template, got `%T'", arg);
3209 return error_mark_node;
3214 if (requires_tmpl_type)
3216 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3217 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3219 if (coerce_template_template_parms (parmparm, argparm, complain,
3220 in_decl, inner_args))
3224 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3226 if (val != error_mark_node
3227 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3228 val = TREE_TYPE (val);
3232 if (in_decl && complain)
3234 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3236 cp_error (" expected a template of type `%D', got `%D'", parm, arg);
3239 val = error_mark_node;
3244 val = groktypename (arg);
3245 if (! processing_template_decl)
3247 /* [basic.link]: A name with no linkage (notably, the
3248 name of a class or enumeration declared in a local
3249 scope) shall not be used to declare an entity with
3250 linkage. This implies that names with no linkage
3251 cannot be used as template arguments. */
3252 tree t = no_linkage_check (val);
3255 if (ANON_AGGRNAME_P (TYPE_IDENTIFIER (t)))
3257 ("template-argument `%T' uses anonymous type", val);
3260 ("template-argument `%T' uses local type `%T'",
3262 return error_mark_node;
3269 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3271 if (processing_template_decl)
3272 arg = maybe_fold_nontype_arg (arg);
3274 if (!uses_template_parms (arg) && !uses_template_parms (t))
3275 /* We used to call digest_init here. However, digest_init
3276 will report errors, which we don't want when complain
3277 is zero. More importantly, digest_init will try too
3278 hard to convert things: for example, `0' should not be
3279 converted to pointer type at this point according to
3280 the standard. Accepting this is not merely an
3281 extension, since deciding whether or not these
3282 conversions can occur is part of determining which
3283 function template to call, or whether a given epxlicit
3284 argument specification is legal. */
3285 val = convert_nontype_argument (t, arg);
3289 if (val == NULL_TREE)
3290 val = error_mark_node;
3291 else if (val == error_mark_node && complain)
3292 cp_error ("could not convert template argument `%E' to `%T'",
3299 /* Convert all template arguments to their appropriate types, and
3300 return a vector containing the innermost resulting template
3301 arguments. If any error occurs, return error_mark_node, and, if
3302 COMPLAIN is non-zero, issue an error message. Some error messages
3303 are issued even if COMPLAIN is zero; for instance, if a template
3304 argument is composed from a local class.
3306 If REQUIRE_ALL_ARGUMENTS is non-zero, all arguments must be
3307 provided in ARGLIST, or else trailing parameters must have default
3308 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3309 deduction for any unspecified trailing arguments.
3311 The resulting TREE_VEC is allocated on a temporary obstack, and
3312 must be explicitly copied if it will be permanent. */
3315 coerce_template_parms (parms, args, in_decl,
3317 require_all_arguments)
3321 int require_all_arguments;
3323 int nparms, nargs, i, lost = 0;
3326 tree new_inner_args;
3328 inner_args = innermost_args (args);
3329 nargs = NUM_TMPL_ARGS (inner_args);
3330 nparms = TREE_VEC_LENGTH (parms);
3334 && require_all_arguments
3335 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3339 cp_error ("wrong number of template arguments (%d, should be %d)",
3343 cp_error_at ("provided for `%D'", in_decl);
3346 return error_mark_node;
3349 new_inner_args = make_tree_vec (nparms);
3350 new_args = add_outermost_template_args (args, new_inner_args);
3351 for (i = 0; i < nparms; i++)
3356 /* Get the Ith template parameter. */
3357 parm = TREE_VEC_ELT (parms, i);
3359 /* Calculate the Ith argument. */
3360 if (inner_args && TREE_CODE (inner_args) == TREE_LIST)
3362 arg = TREE_VALUE (inner_args);
3363 inner_args = TREE_CHAIN (inner_args);
3366 arg = TREE_VEC_ELT (inner_args, i);
3367 /* If no template argument was supplied, look for a default
3369 else if (TREE_PURPOSE (parm) == NULL_TREE)
3371 /* There was no default value. */
3372 my_friendly_assert (!require_all_arguments, 0);
3375 else if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL)
3376 arg = tsubst (TREE_PURPOSE (parm), new_args, complain, in_decl);
3378 arg = tsubst_expr (TREE_PURPOSE (parm), new_args, complain,
3381 /* Now, convert the Ith argument, as necessary. */
3382 if (arg == NULL_TREE)
3383 /* We're out of arguments. */
3385 my_friendly_assert (!require_all_arguments, 0);
3388 else if (arg == error_mark_node)
3390 cp_error ("template argument %d is invalid", i + 1);
3391 arg = error_mark_node;
3394 arg = convert_template_argument (TREE_VALUE (parm),
3395 arg, new_args, complain, i,
3398 if (arg == error_mark_node)
3400 TREE_VEC_ELT (new_inner_args, i) = arg;
3404 return error_mark_node;
3406 return new_inner_args;
3409 /* Returns 1 if template args OT and NT are equivalent. */
3412 template_args_equal (ot, nt)
3417 if (TREE_CODE (nt) != TREE_CODE (ot))
3419 if (TREE_CODE (nt) == TREE_VEC)
3420 /* For member templates */
3421 return comp_template_args (ot, nt);
3422 else if (TYPE_P (ot))
3423 return same_type_p (ot, nt);
3425 return (cp_tree_equal (ot, nt) > 0);
3428 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3429 of template arguments. Returns 0 otherwise. */
3432 comp_template_args (oldargs, newargs)
3433 tree oldargs, newargs;
3437 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3440 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3442 tree nt = TREE_VEC_ELT (newargs, i);
3443 tree ot = TREE_VEC_ELT (oldargs, i);
3445 if (! template_args_equal (ot, nt))
3451 /* Given class template name and parameter list, produce a user-friendly name
3452 for the instantiation. */
3455 mangle_class_name_for_template (name, parms, arglist)
3457 tree parms, arglist;
3459 static struct obstack scratch_obstack;
3460 static char *scratch_firstobj;
3463 if (!scratch_firstobj)
3464 gcc_obstack_init (&scratch_obstack);
3466 obstack_free (&scratch_obstack, scratch_firstobj);
3467 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3469 #define ccat(c) obstack_1grow (&scratch_obstack, (c));
3470 #define cat(s) obstack_grow (&scratch_obstack, (s), strlen (s))
3474 nparms = TREE_VEC_LENGTH (parms);
3475 arglist = innermost_args (arglist);
3476 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3477 for (i = 0; i < nparms; i++)
3479 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3480 tree arg = TREE_VEC_ELT (arglist, i);
3485 if (TREE_CODE (parm) == TYPE_DECL)
3487 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3490 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3492 if (TREE_CODE (arg) == TEMPLATE_DECL)
3494 /* Already substituted with real template. Just output
3495 the template name here */
3496 tree context = DECL_CONTEXT (arg);
3499 /* The template may be defined in a namespace, or
3500 may be a member template. */
3501 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3502 || CLASS_TYPE_P (context),
3504 cat(decl_as_string (DECL_CONTEXT (arg), 0));
3507 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3510 /* Output the parameter declaration */
3511 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3515 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3517 if (TREE_CODE (arg) == TREE_LIST)
3519 /* New list cell was built because old chain link was in
3521 my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270);
3522 arg = TREE_VALUE (arg);
3524 /* No need to check arglist against parmlist here; we did that
3525 in coerce_template_parms, called from lookup_template_class. */
3526 cat (expr_as_string (arg, 0));
3529 char *bufp = obstack_next_free (&scratch_obstack);
3531 while (bufp[offset - 1] == ' ')
3533 obstack_blank_fast (&scratch_obstack, offset);
3535 /* B<C<char> >, not B<C<char>> */
3536 if (bufp[offset - 1] == '>')
3541 return (char *) obstack_base (&scratch_obstack);
3545 classtype_mangled_name (t)
3548 if (CLASSTYPE_TEMPLATE_INFO (t)
3549 /* Specializations have already had their names set up in
3550 lookup_template_class. */
3551 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3553 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3555 /* For non-primary templates, the template parameters are
3556 implicit from their surrounding context. */
3557 if (PRIMARY_TEMPLATE_P (tmpl))
3559 tree name = DECL_NAME (tmpl);
3560 char *mangled_name = mangle_class_name_for_template
3561 (IDENTIFIER_POINTER (name),
3562 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3563 CLASSTYPE_TI_ARGS (t));
3564 tree id = get_identifier (mangled_name);
3565 IDENTIFIER_TEMPLATE (id) = name;
3570 return TYPE_IDENTIFIER (t);
3574 add_pending_template (d)
3577 tree ti = (TYPE_P (d)) ? CLASSTYPE_TEMPLATE_INFO (d) : DECL_TEMPLATE_INFO (d);
3579 if (TI_PENDING_TEMPLATE_FLAG (ti))
3582 *template_tail = tree_cons (build_srcloc_here (), d, NULL_TREE);
3583 template_tail = &TREE_CHAIN (*template_tail);
3584 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3588 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS (which
3589 may be either a _DECL or an overloaded function or an
3590 IDENTIFIER_NODE), and ARGLIST. */
3593 lookup_template_function (fns, arglist)
3598 if (fns == NULL_TREE)
3600 cp_error ("non-template used as template");
3601 return error_mark_node;
3604 type = TREE_TYPE (fns);
3605 if (TREE_CODE (fns) == OVERLOAD || !type)
3606 type = unknown_type_node;
3608 if (processing_template_decl)
3609 return build_min (TEMPLATE_ID_EXPR, type, fns, arglist);
3611 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3614 /* Within the scope of a template class S<T>, the name S gets bound
3615 (in build_self_reference) to a TYPE_DECL for the class, not a
3616 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3617 or one of its enclosing classes, and that type is a template,
3618 return the associated TEMPLATE_DECL. Otherwise, the original
3619 DECL is returned. */
3622 maybe_get_template_decl_from_type_decl (decl)
3625 return (decl != NULL_TREE
3626 && TREE_CODE (decl) == TYPE_DECL
3627 && DECL_ARTIFICIAL (decl)
3628 && CLASS_TYPE_P (TREE_TYPE (decl))
3629 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3630 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3633 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3634 parameters, find the desired type.
3636 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3637 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
3638 be a TREE_LIST if called directly from the parser, and a TREE_VEC
3639 otherwise.) Since ARGLIST is build on the temp_decl_obstack, we must
3640 copy it here to keep it from being reclaimed when the decl storage
3643 IN_DECL, if non-NULL, is the template declaration we are trying to
3646 If ENTERING_SCOPE is non-zero, we are about to enter the scope of
3647 the class we are looking up.
3649 If the template class is really a local class in a template
3650 function, then the FUNCTION_CONTEXT is the function in which it is
3651 being instantiated. */
3654 lookup_template_class (d1, arglist, in_decl, context, entering_scope)
3660 tree template = NULL_TREE, parmlist;
3663 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3665 if (IDENTIFIER_VALUE (d1)
3666 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3667 template = IDENTIFIER_VALUE (d1);
3671 push_decl_namespace (context);
3672 template = lookup_name (d1, /*prefer_type=*/0);
3673 template = maybe_get_template_decl_from_type_decl (template);
3675 pop_decl_namespace ();
3678 context = DECL_CONTEXT (template);
3680 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3682 tree type = TREE_TYPE (d1);
3684 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3685 an implicit typename for the second A. Deal with it. */
3686 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3687 type = TREE_TYPE (type);
3689 if (CLASSTYPE_TEMPLATE_INFO (type))
3691 template = CLASSTYPE_TI_TEMPLATE (type);
3692 d1 = DECL_NAME (template);
3695 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3696 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
3698 template = TYPE_TI_TEMPLATE (d1);
3699 d1 = DECL_NAME (template);
3701 else if (TREE_CODE (d1) == TEMPLATE_DECL
3702 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
3705 d1 = DECL_NAME (template);
3706 context = DECL_CONTEXT (template);
3709 my_friendly_abort (272);
3711 /* With something like `template <class T> class X class X { ... };'
3712 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3713 We don't want to do that, but we have to deal with the situation,
3714 so let's give them some syntax errors to chew on instead of a
3718 cp_error ("`%T' is not a template", d1);
3719 return error_mark_node;
3722 if (context == NULL_TREE)
3723 context = global_namespace;
3725 if (TREE_CODE (template) != TEMPLATE_DECL)
3727 cp_error ("non-template type `%T' used as a template", d1);
3729 cp_error_at ("for template declaration `%D'", in_decl);
3730 return error_mark_node;
3733 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
3735 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
3736 template arguments */
3738 tree parm = copy_template_template_parm (TREE_TYPE (template));
3739 tree template2 = TYPE_STUB_DECL (parm);
3742 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
3744 arglist2 = coerce_template_parms (parmlist, arglist, template, 1, 1);
3745 if (arglist2 == error_mark_node)
3746 return error_mark_node;
3748 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm)
3749 = tree_cons (template2, arglist2, NULL_TREE);
3750 TYPE_SIZE (parm) = 0;
3755 tree template_type = TREE_TYPE (template);
3758 tree found = NULL_TREE;
3761 int is_partial_instantiation;
3763 gen_tmpl = most_general_template (template);
3764 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
3765 parm_depth = TMPL_PARMS_DEPTH (parmlist);
3766 arg_depth = TMPL_ARGS_DEPTH (arglist);
3768 if (arg_depth == 1 && parm_depth > 1)
3770 /* We've been given an incomplete set of template arguments.
3773 template <class T> struct S1 {
3774 template <class U> struct S2 {};
3775 template <class U> struct S2<U*> {};
3778 we will be called with an ARGLIST of `U*', but the
3779 TEMPLATE will be `template <class T> template
3780 <class U> struct S1<T>::S2'. We must fill in the missing
3783 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
3785 arg_depth = TMPL_ARGS_DEPTH (arglist);
3788 /* Now we should enough arguments. */
3789 my_friendly_assert (parm_depth == arg_depth, 0);
3791 /* From here on, we're only interested in the most general
3793 template = gen_tmpl;
3795 /* Calculate the BOUND_ARGS. These will be the args that are
3796 actually tsubst'd into the definition to create the
3800 /* We have multiple levels of arguments to coerce, at once. */
3802 int saved_depth = TMPL_ARGS_DEPTH (arglist);
3804 tree bound_args = make_tree_vec (parm_depth);
3806 for (i = saved_depth,
3807 t = DECL_TEMPLATE_PARMS (template);
3808 i > 0 && t != NULL_TREE;
3809 --i, t = TREE_CHAIN (t))
3811 tree a = coerce_template_parms (TREE_VALUE (t),
3812 arglist, template, 1, 1);
3813 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
3815 /* We temporarily reduce the length of the ARGLIST so
3816 that coerce_template_parms will see only the arguments
3817 corresponding to the template parameters it is
3819 TREE_VEC_LENGTH (arglist)--;
3822 /* Restore the ARGLIST to its full size. */
3823 TREE_VEC_LENGTH (arglist) = saved_depth;
3825 arglist = bound_args;
3829 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
3830 innermost_args (arglist),
3833 if (arglist == error_mark_node)
3834 /* We were unable to bind the arguments. */
3835 return error_mark_node;
3837 /* In the scope of a template class, explicit references to the
3838 template class refer to the type of the template, not any
3839 instantiation of it. For example, in:
3841 template <class T> class C { void f(C<T>); }
3843 the `C<T>' is just the same as `C'. Outside of the
3844 class, however, such a reference is an instantiation. */
3845 if (comp_template_args (TYPE_TI_ARGS (template_type),
3848 found = template_type;
3850 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
3854 /* Note that we use DECL_CONTEXT, rather than
3855 CP_DECL_CONTEXT, so that the termination test is
3856 always just `ctx'. We're not interested in namepace
3858 for (ctx = current_class_type;
3860 ctx = (TYPE_P (ctx)) ? TYPE_CONTEXT (ctx) : DECL_CONTEXT (ctx))
3861 if (same_type_p (ctx, template_type))
3865 /* We're not in the scope of the class, so the
3866 TEMPLATE_TYPE is not the type we want after
3874 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
3875 found; found = TREE_CHAIN (found))
3876 if (comp_template_args (TREE_PURPOSE (found), arglist))
3880 found = TREE_VALUE (found);
3886 /* This type is a "partial instantiation" if any of the template
3887 arguments still inolve template parameters. Note that we set
3888 IS_PARTIAL_INSTANTIATION for partial specializations as
3890 is_partial_instantiation = uses_template_parms (arglist);
3892 if (!is_partial_instantiation
3893 && !PRIMARY_TEMPLATE_P (template)
3894 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
3896 found = xref_tag_from_type (TREE_TYPE (template),
3897 DECL_NAME (template),
3902 /* Create the type. */
3903 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
3905 if (!is_partial_instantiation)
3906 t = start_enum (TYPE_IDENTIFIER (template_type));
3908 /* We don't want to call start_enum for this type, since
3909 the values for the enumeration constants may involve
3910 template parameters. And, no one should be interested
3911 in the enumeration constants for such a type. */
3912 t = make_node (ENUMERAL_TYPE);
3916 t = make_aggr_type (TREE_CODE (template_type));
3917 CLASSTYPE_DECLARED_CLASS (t)
3918 = CLASSTYPE_DECLARED_CLASS (template_type);
3919 CLASSTYPE_GOT_SEMICOLON (t) = 1;
3920 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
3921 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
3923 /* A local class. Make sure the decl gets registered properly. */
3924 if (context == current_function_decl)
3925 pushtag (DECL_NAME (template), t, 0);
3928 /* If we called start_enum or pushtag above, this information
3929 will already be set up. */
3932 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
3934 type_decl = create_implicit_typedef (DECL_NAME (template), t);
3935 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
3936 TYPE_STUB_DECL (t) = type_decl;
3937 DECL_SOURCE_FILE (type_decl)
3938 = DECL_SOURCE_FILE (TYPE_STUB_DECL (template_type));
3939 DECL_SOURCE_LINE (type_decl)
3940 = DECL_SOURCE_LINE (TYPE_STUB_DECL (template_type));
3943 type_decl = TYPE_NAME (t);
3945 /* Set up the template information. We have to figure out which
3946 template is the immediate parent if this is a full
3948 if (parm_depth == 1 || is_partial_instantiation
3949 || !PRIMARY_TEMPLATE_P (template))
3950 /* This case is easy; there are no member templates involved. */
3954 /* This is a full instantiation of a member template. There
3955 should be some partial instantiation of which this is an
3958 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
3959 found; found = TREE_CHAIN (found))
3962 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
3964 /* We only want partial instantiations, here, not
3965 specializations or full instantiations. */
3966 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
3967 || !uses_template_parms (TREE_VALUE (found)))
3970 /* Temporarily reduce by one the number of levels in the
3971 ARGLIST and in FOUND so as to avoid comparing the
3972 last set of arguments. */
3973 TREE_VEC_LENGTH (arglist)--;
3974 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
3976 /* See if the arguments match. If they do, then TMPL is
3977 the partial instantiation we want. */
3978 success = comp_template_args (TREE_PURPOSE (found), arglist);
3980 /* Restore the argument vectors to their full size. */
3981 TREE_VEC_LENGTH (arglist)++;
3982 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
3992 my_friendly_abort (0);
3995 SET_TYPE_TEMPLATE_INFO (t,
3996 tree_cons (found, arglist, NULL_TREE));
3997 DECL_TEMPLATE_INSTANTIATIONS (template)
3998 = tree_cons (arglist, t,
3999 DECL_TEMPLATE_INSTANTIATIONS (template));
4001 if (TREE_CODE (t) == ENUMERAL_TYPE
4002 && !is_partial_instantiation)
4003 /* Now that the type has been registered on the instantiations
4004 list, we set up the enumerators. Because the enumeration
4005 constants may involve the enumeration type itself, we make
4006 sure to register the type first, and then create the
4007 constants. That way, doing tsubst_expr for the enumeration
4008 constants won't result in recursive calls here; we'll find
4009 the instantiation and exit above. */
4010 tsubst_enum (template_type, t, arglist);
4012 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4014 if (TREE_CODE (t) != ENUMERAL_TYPE)
4015 DECL_NAME (type_decl) = classtype_mangled_name (t);
4016 DECL_ASSEMBLER_NAME (type_decl) = DECL_NAME (type_decl);
4017 if (!is_partial_instantiation)
4019 DECL_ASSEMBLER_NAME (type_decl)
4020 = get_identifier (build_overload_name (t, 1, 1));
4022 /* For backwards compatibility; code that uses
4023 -fexternal-templates expects looking up a template to
4024 instantiate it. I think DDD still relies on this.
4025 (jason 8/20/1998) */
4026 if (TREE_CODE (t) != ENUMERAL_TYPE
4027 && flag_external_templates
4028 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4029 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4030 add_pending_template (t);
4033 /* If the type makes use of template parameters, the
4034 code that generates debugging information will crash. */
4035 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4047 /* Called from for_each_template_parm via walk_tree. */
4050 for_each_template_parm_r (tp, walk_subtrees, d)
4056 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4057 tree_fn_t fn = pfd->fn;
4058 void *data = pfd->data;
4061 && for_each_template_parm (TYPE_CONTEXT (t), fn, data))
4062 return error_mark_node;
4064 switch (TREE_CODE (t))
4067 if (TYPE_PTRMEMFUNC_FLAG (t))
4073 if (!TYPE_TEMPLATE_INFO (t))
4075 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4077 return error_mark_node;
4081 /* Since we're not going to walk subtrees, we have to do this
4083 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data))
4084 return error_mark_node;
4087 /* Check the return type. */
4088 if (for_each_template_parm (TREE_TYPE (t), fn, data))
4089 return error_mark_node;
4091 /* Check the parameter types. Since default arguments are not
4092 instantiated until they are needed, the TYPE_ARG_TYPES may
4093 contain expressions that involve template parameters. But,
4094 no-one should be looking at them yet. And, once they're
4095 instantiated, they don't contain template parameters, so
4096 there's no point in looking at them then, either. */
4100 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4101 if (for_each_template_parm (TREE_VALUE (parm), fn, data))
4102 return error_mark_node;
4104 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4105 want walk_tree walking into them itself. */
4112 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4113 && for_each_template_parm (DECL_TI_ARGS (t), fn, data))
4114 return error_mark_node;
4119 if (DECL_CONTEXT (t)
4120 && for_each_template_parm (DECL_CONTEXT (t), fn, data))
4121 return error_mark_node;
4124 case TEMPLATE_TEMPLATE_PARM:
4125 /* Record template parameters such as `T' inside `TT<T>'. */
4126 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t)
4127 && for_each_template_parm (TYPE_TI_ARGS (t), fn, data))
4128 return error_mark_node;
4131 case TEMPLATE_TYPE_PARM:
4132 case TEMPLATE_PARM_INDEX:
4133 if (fn && (*fn)(t, data))
4134 return error_mark_node;
4136 return error_mark_node;
4140 /* A template template parameter is encountered */
4141 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4142 && for_each_template_parm (TREE_TYPE (t), fn, data))
4143 return error_mark_node;
4145 /* Already substituted template template parameter */
4150 if (!fn || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn, data))
4151 return error_mark_node;
4155 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4156 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4157 (TREE_TYPE (t)), fn, data))
4158 return error_mark_node;
4163 /* If there's no type, then this thing must be some expression
4164 involving template parameters. */
4165 if (!fn && !TREE_TYPE (t))
4166 return error_mark_node;
4171 case REINTERPRET_CAST_EXPR:
4172 case CONST_CAST_EXPR:
4173 case STATIC_CAST_EXPR:
4174 case DYNAMIC_CAST_EXPR:
4179 case PSEUDO_DTOR_EXPR:
4181 return error_mark_node;
4188 /* We didn't find any template parameters we liked. */
4192 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM, or
4193 TEMPLATE_PARM_INDEX in T, call FN with the parameter and the DATA.
4194 If FN returns non-zero, the iteration is terminated, and
4195 for_each_template_parm returns 1. Otherwise, the iteration
4196 continues. If FN never returns a non-zero value, the value
4197 returned by for_each_template_parm is 0. If FN is NULL, it is
4198 considered to be the function which always returns 1. */
4201 for_each_template_parm (t, fn, data)
4206 struct pair_fn_data pfd;
4212 /* Walk the tree. */
4213 return walk_tree (&t, for_each_template_parm_r, &pfd) != NULL_TREE;
4217 uses_template_parms (t)
4220 return for_each_template_parm (t, 0, 0);
4223 static struct tinst_level *current_tinst_level;
4224 static struct tinst_level *free_tinst_level;
4225 static int tinst_depth;
4226 extern int max_tinst_depth;
4227 #ifdef GATHER_STATISTICS
4230 static int tinst_level_tick;
4231 static int last_template_error_tick;
4233 /* Print out all the template instantiations that we are currently
4234 working on. If ERR, we are being called from cp_thing, so do
4235 the right thing for an error message. */
4238 print_template_context (err)
4241 struct tinst_level *p = current_tinst_level;
4243 char *file = input_filename;
4247 if (current_function_decl != p->decl
4248 && current_function_decl != NULL_TREE)
4249 /* We can get here during the processing of some synthesized
4250 method. Then, p->decl will be the function that's causing
4255 if (current_function_decl == p->decl)
4256 /* Avoid redundancy with the the "In function" line. */;
4258 fprintf (stderr, "%s: In instantiation of `%s':\n",
4259 file, decl_as_string (p->decl, TS_DECL_TYPE | TS_FUNC_NORETURN));
4267 for (; p; p = p->next)
4269 fprintf (stderr, "%s:%d: instantiated from `%s'\n", file, line,
4270 decl_as_string (p->decl, TS_DECL_TYPE | TS_FUNC_NORETURN));
4274 fprintf (stderr, "%s:%d: instantiated from here\n", file, line);
4277 /* Called from cp_thing to print the template context for an error. */
4280 maybe_print_template_context ()
4282 if (last_template_error_tick == tinst_level_tick
4283 || current_tinst_level == 0)
4286 last_template_error_tick = tinst_level_tick;
4287 print_template_context (1);
4291 push_tinst_level (d)
4294 struct tinst_level *new;
4296 if (tinst_depth >= max_tinst_depth)
4298 /* If the instantiation in question still has unbound template parms,
4299 we don't really care if we can't instantiate it, so just return.
4300 This happens with base instantiation for implicit `typename'. */
4301 if (uses_template_parms (d))
4304 last_template_error_tick = tinst_level_tick;
4305 cp_error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4306 max_tinst_depth, d);
4308 print_template_context (0);
4313 if (free_tinst_level)
4315 new = free_tinst_level;
4316 free_tinst_level = new->next;
4319 new = (struct tinst_level *) xmalloc (sizeof (struct tinst_level));
4323 new->file = input_filename;
4324 new->next = current_tinst_level;
4325 current_tinst_level = new;
4328 #ifdef GATHER_STATISTICS
4329 if (tinst_depth > depth_reached)
4330 depth_reached = tinst_depth;
4340 struct tinst_level *old = current_tinst_level;
4342 /* Restore the filename and line number stashed away when we started
4343 this instantiation. */
4345 input_filename = old->file;
4346 extract_interface_info ();
4348 current_tinst_level = old->next;
4349 old->next = free_tinst_level;
4350 free_tinst_level = old;
4355 struct tinst_level *
4358 struct tinst_level *p = current_tinst_level;
4361 for (; p->next ; p = p->next )
4366 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4367 vector of template arguments, as for tsubst.
4369 Returns an appropriate tsbust'd friend declaration. */
4372 tsubst_friend_function (decl, args)
4378 char *file = input_filename;
4380 lineno = DECL_SOURCE_LINE (decl);
4381 input_filename = DECL_SOURCE_FILE (decl);
4383 if (TREE_CODE (decl) == FUNCTION_DECL
4384 && DECL_TEMPLATE_INSTANTIATION (decl)
4385 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4386 /* This was a friend declared with an explicit template
4387 argument list, e.g.:
4391 to indicate that f was a template instantiation, not a new
4392 function declaration. Now, we have to figure out what
4393 instantiation of what template. */
4400 = lookup_template_function (tsubst_expr (DECL_TI_TEMPLATE (decl),
4401 args, /*complain=*/1,
4403 tsubst (DECL_TI_ARGS (decl),
4404 args, /*complain=*/1,
4406 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4407 tmpl = determine_specialization (template_id, new_friend,
4409 /*need_member_template=*/0);
4410 new_friend = instantiate_template (tmpl, new_args);
4414 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4416 /* The NEW_FRIEND will look like an instantiation, to the
4417 compiler, but is not an instantiation from the point of view of
4418 the language. For example, we might have had:
4420 template <class T> struct S {
4421 template <class U> friend void f(T, U);
4424 Then, in S<int>, template <class U> void f(int, U) is not an
4425 instantiation of anything. */
4426 DECL_USE_TEMPLATE (new_friend) = 0;
4427 if (TREE_CODE (decl) == TEMPLATE_DECL)
4428 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4430 /* The mangled name for the NEW_FRIEND is incorrect. The call to
4431 tsubst will have resulted in a call to
4432 set_mangled_name_for_template_decl. But, the function is not a
4433 template instantiation and should not be mangled like one.
4434 Therefore, we remangle the function name. We don't have to do
4435 this if the NEW_FRIEND is a template since
4436 set_mangled_name_for_template_decl doesn't do anything if the
4437 function declaration still uses template arguments. */
4438 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4440 set_mangled_name_for_decl (new_friend);
4441 DECL_RTL (new_friend) = 0;
4442 make_decl_rtl (new_friend, NULL_PTR, 1);
4445 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4448 tree new_friend_template_info;
4449 tree new_friend_result_template_info;
4451 int new_friend_is_defn;
4453 /* We must save some information from NEW_FRIEND before calling
4454 duplicate decls since that function will free NEW_FRIEND if
4456 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4457 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4459 /* This declaration is a `primary' template. */
4460 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4463 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4464 new_friend_result_template_info
4465 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4469 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4470 new_friend_result_template_info = NULL_TREE;
4473 /* Inside pushdecl_namespace_level, we will push into the
4474 current namespace. However, the friend function should go
4475 into the namespace of the template. */
4476 ns = decl_namespace_context (new_friend);
4477 push_nested_namespace (ns);
4478 old_decl = pushdecl_namespace_level (new_friend);
4479 pop_nested_namespace (ns);
4481 if (old_decl != new_friend)
4483 /* This new friend declaration matched an existing
4484 declaration. For example, given:
4486 template <class T> void f(T);
4487 template <class U> class C {
4488 template <class T> friend void f(T) {}
4491 the friend declaration actually provides the definition
4492 of `f', once C has been instantiated for some type. So,
4493 old_decl will be the out-of-class template declaration,
4494 while new_friend is the in-class definition.
4496 But, if `f' was called before this point, the
4497 instantiation of `f' will have DECL_TI_ARGS corresponding
4498 to `T' but not to `U', references to which might appear
4499 in the definition of `f'. Previously, the most general
4500 template for an instantiation of `f' was the out-of-class
4501 version; now it is the in-class version. Therefore, we
4502 run through all specialization of `f', adding to their
4503 DECL_TI_ARGS appropriately. In particular, they need a
4504 new set of outer arguments, corresponding to the
4505 arguments for this class instantiation.
4507 The same situation can arise with something like this:
4510 template <class T> class C {
4514 when `C<int>' is instantiated. Now, `f(int)' is defined
4517 if (!new_friend_is_defn)
4518 /* On the other hand, if the in-class declaration does
4519 *not* provide a definition, then we don't want to alter
4520 existing definitions. We can just leave everything
4525 /* Overwrite whatever template info was there before, if
4526 any, with the new template information pertaining to
4528 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4530 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4531 /* duplicate_decls will take care of this case. */
4536 tree new_friend_args;
4538 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4539 = new_friend_result_template_info;
4541 new_friend_args = TI_ARGS (new_friend_template_info);
4542 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4546 tree spec = TREE_VALUE (t);
4549 = add_outermost_template_args (new_friend_args,
4550 DECL_TI_ARGS (spec));
4553 /* Now, since specializations are always supposed to
4554 hang off of the most general template, we must move
4556 t = most_general_template (old_decl);
4559 DECL_TEMPLATE_SPECIALIZATIONS (t)
4560 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4561 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4562 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4567 /* The information from NEW_FRIEND has been merged into OLD_DECL
4568 by duplicate_decls. */
4569 new_friend = old_decl;
4572 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4574 /* Check to see that the declaration is really present, and,
4575 possibly obtain an improved declaration. */
4576 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4585 input_filename = file;
4589 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4590 template arguments, as for tsubst.
4592 Returns an appropriate tsbust'd friend type. */
4595 tsubst_friend_class (friend_tmpl, args)
4602 /* First, we look for a class template. */
4603 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4605 /* But, if we don't find one, it might be because we're in a
4606 situation like this:
4614 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4615 for `S<int>', not the TEMPLATE_DECL. */
4616 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4618 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4619 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4622 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4624 /* The friend template has already been declared. Just
4625 check to see that the declarations match, and install any new
4626 default parameters. We must tsubst the default parameters,
4627 of course. We only need the innermost template parameters
4628 because that is all that redeclare_class_template will look
4631 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4632 args, /*complain=*/1);
4633 redeclare_class_template (TREE_TYPE (tmpl), parms);
4634 friend_type = TREE_TYPE (tmpl);
4638 /* The friend template has not already been declared. In this
4639 case, the instantiation of the template class will cause the
4640 injection of this template into the global scope. */
4641 tmpl = tsubst (friend_tmpl, args, /*complain=*/1, NULL_TREE);
4643 /* The new TMPL is not an instantiation of anything, so we
4644 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
4645 the new type because that is supposed to be the corresponding
4646 template decl, i.e., TMPL. */
4647 DECL_USE_TEMPLATE (tmpl) = 0;
4648 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
4649 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
4651 /* Inject this template into the global scope. */
4652 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
4659 instantiate_class_template (type)
4662 tree template, args, pattern, t;
4665 if (type == error_mark_node)
4666 return error_mark_node;
4668 if (TYPE_BEING_DEFINED (type) || COMPLETE_TYPE_P (type))
4671 /* Figure out which template is being instantiated. */
4672 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
4673 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
4675 /* Figure out which arguments are being used to do the
4677 args = CLASSTYPE_TI_ARGS (type);
4678 PARTIAL_INSTANTIATION_P (type) = uses_template_parms (args);
4680 if (pedantic && PARTIAL_INSTANTIATION_P (type))
4681 /* If this is a partial instantiation, then we can't instantiate
4682 the type; there's no telling whether or not one of the
4683 template parameters might eventually be instantiated to some
4684 value that results in a specialization being used. For
4696 Now, the `S<U>' in `f<int>' is the specialization, not an
4697 instantiation of the original template. */
4700 /* Determine what specialization of the original template to
4702 if (PARTIAL_INSTANTIATION_P (type))
4703 /* There's no telling which specialization is appropriate at this
4704 point. Since all peeking at the innards of this partial
4705 instantiation are extensions (like the "implicit typename"
4706 extension, which allows users to omit the keyword `typename' on
4707 names that are declared as types in template base classes), we
4708 are free to do what we please.
4710 Trying to figure out which partial instantiation to use can
4711 cause a crash. (Some of the template arguments don't even have
4712 types.) So, we just use the most general version. */
4716 t = most_specialized_class (template, args);
4718 if (t == error_mark_node)
4720 const char *str = "candidates are:";
4721 cp_error ("ambiguous class template instantiation for `%#T'", type);
4722 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
4725 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4728 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
4732 TYPE_BEING_DEFINED (type) = 1;
4733 return error_mark_node;
4738 pattern = TREE_TYPE (t);
4740 pattern = TREE_TYPE (template);
4742 /* If the template we're instantiating is incomplete, then clearly
4743 there's nothing we can do. */
4744 if (!COMPLETE_TYPE_P (pattern))
4747 /* If this is a partial instantiation, don't tsubst anything. We will
4748 only use this type for implicit typename, so the actual contents don't
4749 matter. All that matters is whether a particular name is a type. */
4750 if (PARTIAL_INSTANTIATION_P (type))
4752 /* The fields set here must be kept in sync with those cleared
4753 in begin_class_definition. */
4754 TYPE_BINFO_BASETYPES (type) = TYPE_BINFO_BASETYPES (pattern);
4755 TYPE_FIELDS (type) = TYPE_FIELDS (pattern);
4756 TYPE_METHODS (type) = TYPE_METHODS (pattern);
4757 CLASSTYPE_TAGS (type) = CLASSTYPE_TAGS (pattern);
4758 /* Pretend that the type is complete, so that we will look
4759 inside it during name lookup and such. */
4760 TYPE_SIZE (type) = bitsize_zero_node;
4764 /* If we've recursively instantiated too many templates, stop. */
4765 if (! push_tinst_level (type))
4768 /* Now we're really doing the instantiation. Mark the type as in
4769 the process of being defined. */
4770 TYPE_BEING_DEFINED (type) = 1;
4772 maybe_push_to_top_level (uses_template_parms (type));
4776 /* This TYPE is actually a instantiation of of a partial
4777 specialization. We replace the innermost set of ARGS with
4778 the arguments appropriate for substitution. For example,
4781 template <class T> struct S {};
4782 template <class T> struct S<T*> {};
4784 and supposing that we are instantiating S<int*>, ARGS will
4785 present be {int*} but we need {int}. */
4787 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4790 /* If there were multiple levels in ARGS, replacing the
4791 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
4792 want, so we make a copy first. */
4793 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
4795 args = copy_node (args);
4796 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
4802 if (flag_external_templates)
4804 if (flag_alt_external_templates)
4806 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
4807 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
4808 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4809 = (! CLASSTYPE_INTERFACE_ONLY (type)
4810 && CLASSTYPE_INTERFACE_KNOWN (type));
4814 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
4815 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
4816 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
4817 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4818 = (! CLASSTYPE_INTERFACE_ONLY (type)
4819 && CLASSTYPE_INTERFACE_KNOWN (type));
4824 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
4825 CLASSTYPE_VTABLE_NEEDS_WRITING (type) = 1;
4828 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
4829 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
4830 TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern);
4831 TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern);
4832 TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern);
4833 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
4834 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
4835 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
4836 TYPE_VEC_DELETE_TAKES_SIZE (type) = TYPE_VEC_DELETE_TAKES_SIZE (pattern);
4837 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
4838 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
4839 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
4840 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
4841 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
4842 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
4843 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
4844 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
4845 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
4846 TYPE_USES_MULTIPLE_INHERITANCE (type)
4847 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
4848 TYPE_USES_VIRTUAL_BASECLASSES (type)
4849 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
4850 TYPE_PACKED (type) = TYPE_PACKED (pattern);
4851 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
4852 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
4853 if (ANON_AGGR_TYPE_P (pattern))
4854 SET_ANON_AGGR_TYPE_P (type);
4856 if (TYPE_BINFO_BASETYPES (pattern))
4858 tree base_list = NULL_TREE;
4859 tree pbases = TYPE_BINFO_BASETYPES (pattern);
4862 /* Substitute into each of the bases to determine the actual
4864 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
4870 pbase = TREE_VEC_ELT (pbases, i);
4872 /* Substitue to figure out the base class. */
4873 base = tsubst (BINFO_TYPE (pbase), args,
4874 /*complain=*/1, NULL_TREE);
4875 if (base == error_mark_node)
4878 /* Calculate the correct access node. */
4879 if (TREE_VIA_VIRTUAL (pbase))
4881 if (TREE_VIA_PUBLIC (pbase))
4882 access = access_public_virtual_node;
4883 else if (TREE_VIA_PROTECTED (pbase))
4884 access = access_protected_virtual_node;
4886 access = access_private_virtual_node;
4890 if (TREE_VIA_PUBLIC (pbase))
4891 access = access_public_node;
4892 else if (TREE_VIA_PROTECTED (pbase))
4893 access = access_protected_node;
4895 access = access_private_node;
4898 base_list = tree_cons (access, base, base_list);
4901 /* The list is now in reverse order; correct that. */
4902 base_list = nreverse (base_list);
4904 /* Now call xref_basetypes to set up all the base-class
4906 xref_basetypes (TREE_CODE (pattern) == RECORD_TYPE
4907 ? (CLASSTYPE_DECLARED_CLASS (pattern)
4908 ? class_type_node : record_type_node)
4910 DECL_NAME (TYPE_NAME (pattern)),
4915 /* Now that our base classes are set up, enter the scope of the
4916 class, so that name lookups into base classes, etc. will work
4917 corectly. This is precisely analagous to what we do in
4918 begin_class_definition when defining an ordinary non-template
4920 pushclass (type, 1);
4922 for (t = CLASSTYPE_TAGS (pattern); t; t = TREE_CHAIN (t))
4924 tree tag = TREE_VALUE (t);
4925 tree name = TYPE_IDENTIFIER (tag);
4928 newtag = tsubst (tag, args, /*complain=*/1, NULL_TREE);
4929 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
4931 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
4932 /* Unfortunately, lookup_template_class sets
4933 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
4934 instantiation (i.e., for the type of a member template
4935 class nested within a template class.) This behavior is
4936 required for maybe_process_partial_specialization to work
4937 correctly, but is not accurate in this case; the TAG is not
4938 an instantiation of anything. (The corresponding
4939 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
4940 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
4942 /* Now, we call pushtag to put this NEWTAG into the scope of
4943 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
4944 pushtag calling push_template_decl. We don't have to do
4945 this for enums because it will already have been done in
4948 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
4949 pushtag (name, newtag, /*globalize=*/0);
4953 /* Don't replace enum constants here. */
4954 for (t = TYPE_FIELDS (pattern); t; t = TREE_CHAIN (t))
4955 if (TREE_CODE (t) != CONST_DECL)
4959 /* The the file and line for this declaration, to assist in
4960 error message reporting. Since we called push_tinst_level
4961 above, we don't need to restore these. */
4962 lineno = DECL_SOURCE_LINE (t);
4963 input_filename = DECL_SOURCE_FILE (t);
4965 r = tsubst (t, args, /*complain=*/1, NULL_TREE);
4966 if (TREE_CODE (r) == VAR_DECL)
4970 if (DECL_DEFINED_IN_CLASS_P (r))
4971 init = tsubst_expr (DECL_INITIAL (t), args,
4972 /*complain=*/1, NULL_TREE);
4976 finish_static_data_member_decl (r, init,
4977 /*asmspec_tree=*/NULL_TREE,
4980 if (DECL_DEFINED_IN_CLASS_P (r))
4981 check_static_variable_definition (r, TREE_TYPE (r));
4984 /* R will have a TREE_CHAIN if and only if it has already been
4985 processed by finish_member_declaration. This can happen
4986 if, for example, it is a TYPE_DECL for a class-scoped
4987 ENUMERAL_TYPE; such a thing will already have been added to
4988 the field list by tsubst_enum above. */
4989 if (!TREE_CHAIN (r))
4991 set_current_access_from_decl (r);
4992 finish_member_declaration (r);
4996 /* Set up the list (TYPE_METHODS) and vector (CLASSTYPE_METHOD_VEC)
4997 for this instantiation. */
4998 for (t = TYPE_METHODS (pattern); t; t = TREE_CHAIN (t))
5000 tree r = tsubst (t, args, /*complain=*/1, NULL_TREE);
5001 set_current_access_from_decl (r);
5002 finish_member_declaration (r);
5005 /* Construct the DECL_FRIENDLIST for the new class type. */
5006 typedecl = TYPE_MAIN_DECL (type);
5007 for (t = DECL_FRIENDLIST (TYPE_MAIN_DECL (pattern));
5013 for (friends = TREE_VALUE (t);
5014 friends != NULL_TREE;
5015 friends = TREE_CHAIN (friends))
5016 if (TREE_PURPOSE (friends) == error_mark_node)
5018 tsubst_friend_function (TREE_VALUE (friends),
5021 my_friendly_abort (20000216);
5024 for (t = CLASSTYPE_FRIEND_CLASSES (pattern);
5028 tree friend_type = TREE_VALUE (t);
5029 tree new_friend_type;
5031 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5032 new_friend_type = tsubst_friend_class (friend_type, args);
5033 else if (uses_template_parms (friend_type))
5034 new_friend_type = tsubst (friend_type, args, /*complain=*/1,
5038 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5040 /* The call to xref_tag_from_type does injection for friend
5042 push_nested_namespace (ns);
5044 xref_tag_from_type (friend_type, NULL_TREE, 1);
5045 pop_nested_namespace (ns);
5048 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5049 /* Trick make_friend_class into realizing that the friend
5050 we're adding is a template, not an ordinary class. It's
5051 important that we use make_friend_class since it will
5052 perform some error-checking and output cross-reference
5054 ++processing_template_decl;
5056 make_friend_class (type, new_friend_type);
5058 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5059 --processing_template_decl;
5062 for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t))
5063 if (TREE_CODE (t) == FIELD_DECL)
5065 TREE_TYPE (t) = complete_type (TREE_TYPE (t));
5066 require_complete_type (t);
5069 /* Set the file and line number information to whatever is given for
5070 the class itself. This puts error messages involving generated
5071 implicit functions at a predictable point, and the same point
5072 that would be used for non-template classes. */
5073 lineno = DECL_SOURCE_LINE (typedecl);
5074 input_filename = DECL_SOURCE_FILE (typedecl);
5076 unreverse_member_declarations (type);
5077 finish_struct_1 (type);
5078 CLASSTYPE_GOT_SEMICOLON (type) = 1;
5080 /* Clear this now so repo_template_used is happy. */
5081 TYPE_BEING_DEFINED (type) = 0;
5082 repo_template_used (type);
5084 /* Now that the class is complete, instantiate default arguments for
5085 any member functions. We don't do this earlier because the
5086 default arguments may reference members of the class. */
5087 if (!PRIMARY_TEMPLATE_P (template))
5088 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5089 if (TREE_CODE (t) == FUNCTION_DECL
5090 /* Implicitly generated member functions will not have tmplate
5091 information; they are not instantiations, but instead are
5092 created "fresh" for each instantiation. */
5093 && DECL_TEMPLATE_INFO (t))
5094 tsubst_default_arguments (t);
5097 pop_from_top_level ();
5107 if (t1 == NULL_TREE)
5108 return t2 == NULL_TREE;
5109 if (t2 == NULL_TREE)
5111 /* Don't care if one declares its arg const and the other doesn't -- the
5112 main variant of the arg type is all that matters. */
5113 if (TYPE_MAIN_VARIANT (TREE_VALUE (t1))
5114 != TYPE_MAIN_VARIANT (TREE_VALUE (t2)))
5116 return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2));
5119 /* If arg is a non-type template parameter that does not depend on template
5120 arguments, fold it like we weren't in the body of a template. */
5123 maybe_fold_nontype_arg (arg)
5126 /* If we're not in a template, ARG is already as simple as it's going to
5127 get, and trying to reprocess the trees will break. */
5128 if (! processing_template_decl)
5131 if (!TYPE_P (arg) && !uses_template_parms (arg))
5133 /* Sometimes, one of the args was an expression involving a
5134 template constant parameter, like N - 1. Now that we've
5135 tsubst'd, we might have something like 2 - 1. This will
5136 confuse lookup_template_class, so we do constant folding
5137 here. We have to unset processing_template_decl, to
5138 fool build_expr_from_tree() into building an actual
5141 int saved_processing_template_decl = processing_template_decl;
5142 processing_template_decl = 0;
5143 arg = fold (build_expr_from_tree (arg));
5144 processing_template_decl = saved_processing_template_decl;
5149 /* Return the TREE_VEC with the arguments for the innermost template header,
5150 where ARGS is either that or the VEC of VECs for all the
5154 innermost_args (args)
5157 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
5160 /* Substitute ARGS into the vector of template arguments T. */
5163 tsubst_template_arg_vector (t, args, complain)
5168 int len = TREE_VEC_LENGTH (t), need_new = 0, i;
5169 tree *elts = (tree *) alloca (len * sizeof (tree));
5171 bzero ((char *) elts, len * sizeof (tree));
5173 for (i = 0; i < len; i++)
5175 if (TREE_VEC_ELT (t, i) != NULL_TREE
5176 && TREE_CODE (TREE_VEC_ELT (t, i)) == TREE_VEC)
5177 elts[i] = tsubst_template_arg_vector (TREE_VEC_ELT (t, i),
5180 elts[i] = maybe_fold_nontype_arg
5181 (tsubst_expr (TREE_VEC_ELT (t, i), args, complain,
5184 if (elts[i] != TREE_VEC_ELT (t, i))
5191 t = make_tree_vec (len);
5192 for (i = 0; i < len; i++)
5193 TREE_VEC_ELT (t, i) = elts[i];
5198 /* Return the result of substituting ARGS into the template parameters
5199 given by PARMS. If there are m levels of ARGS and m + n levels of
5200 PARMS, then the result will contain n levels of PARMS. For
5201 example, if PARMS is `template <class T> template <class U>
5202 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5203 result will be `template <int*, double, class V>'. */
5206 tsubst_template_parms (parms, args, complain)
5214 for (new_parms = &r;
5215 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5216 new_parms = &(TREE_CHAIN (*new_parms)),
5217 parms = TREE_CHAIN (parms))
5220 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5223 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5225 tree default_value =
5226 TREE_PURPOSE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5228 TREE_VALUE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5230 TREE_VEC_ELT (new_vec, i)
5231 = build_tree_list (tsubst (default_value, args, complain,
5233 tsubst (parm_decl, args, complain,
5238 tree_cons (build_int_2 (0, (TMPL_PARMS_DEPTH (parms)
5239 - TMPL_ARGS_DEPTH (args))),
5240 new_vec, NULL_TREE);
5246 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5247 type T. If T is not an aggregate or enumeration type, it is
5248 handled as if by tsubst. IN_DECL is as for tsubst. If
5249 ENTERING_SCOPE is non-zero, T is the context for a template which
5250 we are presently tsubst'ing. Return the subsituted value. */
5253 tsubst_aggr_type (t, args, complain, in_decl, entering_scope)
5263 switch (TREE_CODE (t))
5266 if (TYPE_PTRMEMFUNC_P (t))
5268 tree r = build_ptrmemfunc_type
5269 (tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl));
5270 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5274 /* else fall through */
5277 if (TYPE_TEMPLATE_INFO (t))
5283 /* First, determine the context for the type we are looking
5285 if (TYPE_CONTEXT (t) != NULL_TREE)
5286 context = tsubst_aggr_type (TYPE_CONTEXT (t), args,
5288 in_decl, /*entering_scope=*/1);
5290 context = NULL_TREE;
5292 /* Then, figure out what arguments are appropriate for the
5293 type we are trying to find. For example, given:
5295 template <class T> struct S;
5296 template <class T, class U> void f(T, U) { S<U> su; }
5298 and supposing that we are instantiating f<int, double>,
5299 then our ARGS will be {int, double}, but, when looking up
5300 S we only want {double}. */
5301 argvec = tsubst_template_arg_vector (TYPE_TI_ARGS (t), args,
5304 r = lookup_template_class (t, argvec, in_decl, context,
5307 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5311 /* This is not a template type, so there's nothing to do. */
5315 return tsubst (t, args, complain, in_decl);
5319 /* Substitute into the default argument ARG (a default argument for
5320 FN), which has the indicated TYPE. */
5323 tsubst_default_argument (fn, type, arg)
5328 /* This default argument came from a template. Instantiate the
5329 default argument here, not in tsubst. In the case of
5338 we must be careful to do name lookup in the scope of S<T>,
5339 rather than in the current class. */
5340 if (DECL_CLASS_SCOPE_P (fn))
5341 pushclass (DECL_CONTEXT (fn), 2);
5343 arg = tsubst_expr (arg, DECL_TI_ARGS (fn), /*complain=*/1, NULL_TREE);
5345 if (DECL_CLASS_SCOPE_P (fn))
5348 /* Make sure the default argument is reasonable. */
5349 arg = check_default_argument (type, arg);
5354 /* Substitute into all the default arguments for FN. */
5357 tsubst_default_arguments (fn)
5363 tmpl_args = DECL_TI_ARGS (fn);
5365 /* If this function is not yet instantiated, we certainly don't need
5366 its default arguments. */
5367 if (uses_template_parms (tmpl_args))
5370 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5372 arg = TREE_CHAIN (arg))
5373 if (TREE_PURPOSE (arg))
5374 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5376 TREE_PURPOSE (arg));
5379 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5380 (already computed) substitution of ARGS into TREE_TYPE (T), if
5381 appropriate. Return the result of the substitution. IN_DECL is as
5385 tsubst_decl (t, args, type, in_decl)
5392 char* saved_filename;
5395 /* Set the filename and linenumber to improve error-reporting. */
5396 saved_lineno = lineno;
5397 saved_filename = input_filename;
5398 lineno = DECL_SOURCE_LINE (t);
5399 input_filename = DECL_SOURCE_FILE (t);
5401 switch (TREE_CODE (t))
5405 /* We can get here when processing a member template function
5406 of a template class. */
5407 tree decl = DECL_TEMPLATE_RESULT (t);
5409 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5411 if (!is_template_template_parm)
5413 /* We might already have an instance of this template.
5414 The ARGS are for the surrounding class type, so the
5415 full args contain the tsubst'd args for the context,
5416 plus the innermost args from the template decl. */
5417 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5418 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5419 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5422 full_args = tsubst_template_arg_vector (tmpl_args, args,
5425 /* tsubst_template_arg_vector doesn't copy the vector if
5426 nothing changed. But, *something* should have
5428 my_friendly_assert (full_args != tmpl_args, 0);
5430 spec = retrieve_specialization (t, full_args);
5431 if (spec != NULL_TREE)
5438 /* Make a new template decl. It will be similar to the
5439 original, but will record the current template arguments.
5440 We also create a new function declaration, which is just
5441 like the old one, but points to this new template, rather
5442 than the old one. */
5444 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5445 TREE_CHAIN (r) = NULL_TREE;
5447 if (is_template_template_parm)
5449 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5450 DECL_TEMPLATE_RESULT (r) = new_decl;
5451 TREE_TYPE (r) = TREE_TYPE (new_decl);
5456 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5457 /*complain=*/1, in_decl,
5458 /*entering_scope=*/1);
5459 DECL_VIRTUAL_CONTEXT (r)
5460 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5461 /*complain=*/1, in_decl,
5462 /*entering_scope=*/1);
5463 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5465 if (TREE_CODE (decl) == TYPE_DECL)
5467 tree new_type = tsubst (TREE_TYPE (t), args,
5468 /*complain=*/1, in_decl);
5469 TREE_TYPE (r) = new_type;
5470 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5471 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5472 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5476 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5478 DECL_TEMPLATE_RESULT (r) = new_decl;
5479 DECL_TI_TEMPLATE (new_decl) = r;
5480 TREE_TYPE (r) = TREE_TYPE (new_decl);
5481 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5484 SET_DECL_IMPLICIT_INSTANTIATION (r);
5485 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5486 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5488 /* The template parameters for this new template are all the
5489 template parameters for the old template, except the
5490 outermost level of parameters. */
5491 DECL_TEMPLATE_PARMS (r)
5492 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5495 if (PRIMARY_TEMPLATE_P (t))
5496 DECL_PRIMARY_TEMPLATE (r) = r;
5498 /* We don't partially instantiate partial specializations. */
5499 if (TREE_CODE (decl) == TYPE_DECL)
5502 for (spec = DECL_TEMPLATE_SPECIALIZATIONS (t);
5504 spec = TREE_CHAIN (spec))
5506 /* It helps to consider example here. Consider:
5517 Now, for example, we are instantiating S<int>::f(U u).
5518 We want to make a template:
5523 It will have a specialization, for the case U = int*, of
5527 void S<int>::f<int*>(int*);
5529 This specialization will be an instantiation of
5530 the specialization given in the declaration of S, with
5531 argument list int*. */
5533 tree fn = TREE_VALUE (spec);
5537 if (!DECL_TEMPLATE_SPECIALIZATION (fn))
5538 /* Instantiations are on the same list, but they're of
5539 no concern to us. */
5542 if (TREE_CODE (fn) != TEMPLATE_DECL)
5543 /* A full specialization. There's no need to record
5547 spec_args = tsubst (DECL_TI_ARGS (fn), args,
5548 /*complain=*/1, in_decl);
5550 = tsubst (DECL_TEMPLATE_RESULT (most_general_template (fn)),
5551 spec_args, /*complain=*/1, in_decl);
5552 DECL_TI_TEMPLATE (new_fn) = fn;
5553 register_specialization (new_fn, r,
5554 innermost_args (spec_args));
5557 /* Record this partial instantiation. */
5558 register_specialization (r, t,
5559 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5567 tree argvec = NULL_TREE;
5574 /* Nobody should be tsubst'ing into non-template functions. */
5575 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5577 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5581 /* Calculate the most general template of which R is a
5582 specialization, and the complete set of arguments used to
5584 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5586 = tsubst_template_arg_vector (DECL_TI_ARGS
5587 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5588 args, /*complain=*/1);
5590 /* Check to see if we already have this specialization. */
5591 spec = retrieve_specialization (gen_tmpl, argvec);
5599 /* Here, we deal with the peculiar case:
5601 template <class T> struct S {
5602 template <class U> friend void f();
5604 template <class U> void f() {}
5606 template void f<double>();
5608 Here, the ARGS for the instantiation of will be {int,
5609 double}. But, we only need as many ARGS as there are
5610 levels of template parameters in CODE_PATTERN. We are
5611 careful not to get fooled into reducing the ARGS in
5614 template <class T> struct S { template <class U> void f(U); }
5615 template <class T> template <> void S<T>::f(int) {}
5617 which we can spot because the pattern will be a
5618 specialization in this case. */
5619 args_depth = TMPL_ARGS_DEPTH (args);
5621 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5622 if (args_depth > parms_depth
5623 && !DECL_TEMPLATE_SPECIALIZATION (t))
5625 my_friendly_assert (DECL_FRIEND_P (t), 0);
5627 if (parms_depth > 1)
5631 args = make_tree_vec (parms_depth);
5632 for (i = 0; i < parms_depth; ++i)
5633 TREE_VEC_ELT (args, i) =
5634 TREE_VEC_ELT (args, i + (args_depth - parms_depth));
5637 args = TREE_VEC_ELT (args, args_depth - parms_depth);
5642 /* This special case arises when we have something like this:
5644 template <class T> struct S {
5645 friend void f<int>(int, double);
5648 Here, the DECL_TI_TEMPLATE for the friend declaration
5649 will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are
5650 being called from tsubst_friend_function, and we want
5651 only to create a new decl (R) with appropriate types so
5652 that we can call determine_specialization. */
5653 my_friendly_assert ((TREE_CODE (DECL_TI_TEMPLATE (t))
5655 || (TREE_CODE (DECL_TI_TEMPLATE (t))
5656 == IDENTIFIER_NODE), 0);
5657 gen_tmpl = NULL_TREE;
5660 if (DECL_CLASS_SCOPE_P (t))
5662 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5666 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5668 /*entering_scope=*/1);
5673 ctx = DECL_CONTEXT (t);
5675 type = tsubst (type, args, /*complain=*/1, in_decl);
5676 if (type == error_mark_node)
5677 return error_mark_node;
5679 /* We do NOT check for matching decls pushed separately at this
5680 point, as they may not represent instantiations of this
5681 template, and in any case are considered separate under the
5682 discrete model. Instead, see add_maybe_template. */
5684 DECL_USE_TEMPLATE (r) = 0;
5685 TREE_TYPE (r) = type;
5687 DECL_CONTEXT (r) = ctx;
5688 DECL_VIRTUAL_CONTEXT (r)
5689 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5691 /*entering_scope=*/1);
5693 if (member && IDENTIFIER_TYPENAME_P (DECL_NAME (r)))
5694 /* Type-conversion operator. Reconstruct the name, in
5695 case it's the name of one of the template's parameters. */
5696 DECL_NAME (r) = build_typename_overload (TREE_TYPE (type));
5698 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5700 DECL_TEMPLATE_RESULT (r) = NULL_TREE;
5702 TREE_STATIC (r) = 0;
5703 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5704 DECL_EXTERNAL (r) = 1;
5705 DECL_INTERFACE_KNOWN (r) = 0;
5706 DECL_DEFER_OUTPUT (r) = 0;
5707 TREE_CHAIN (r) = NULL_TREE;
5708 DECL_PENDING_INLINE_INFO (r) = 0;
5709 DECL_PENDING_INLINE_P (r) = 0;
5712 /* Set up the DECL_TEMPLATE_INFO for R and compute its mangled
5713 name. There's no need to do this in the special friend
5714 case mentioned above where GEN_TMPL is NULL. */
5717 DECL_TEMPLATE_INFO (r)
5718 = tree_cons (gen_tmpl, argvec, NULL_TREE);
5719 SET_DECL_IMPLICIT_INSTANTIATION (r);
5720 register_specialization (r, gen_tmpl, argvec);
5722 /* Set the mangled name for R. */
5723 if (DECL_DESTRUCTOR_P (t))
5724 DECL_ASSEMBLER_NAME (r) = build_destructor_name (ctx);
5727 /* Instantiations of template functions must be mangled
5728 specially, in order to conform to 14.5.5.1
5729 [temp.over.link]. */
5730 tree tmpl = DECL_TI_TEMPLATE (t);
5732 /* TMPL will be NULL if this is a specialization of a
5733 member function of a template class. */
5734 if (name_mangling_version < 1
5735 || tmpl == NULL_TREE
5736 || (member && !is_member_template (tmpl)
5737 && !DECL_TEMPLATE_INFO (tmpl)))
5738 set_mangled_name_for_decl (r);
5740 set_mangled_name_for_template_decl (r);
5744 make_decl_rtl (r, NULL_PTR, 1);
5746 /* Like grokfndecl. If we don't do this, pushdecl will
5747 mess up our TREE_CHAIN because it doesn't find a
5748 previous decl. Sigh. */
5750 && ! uses_template_parms (r)
5751 && (IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r))
5753 SET_IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r), r);
5755 /* We're not supposed to instantiate default arguments
5756 until they are called, for a template. But, for a
5759 template <class T> void f ()
5760 { extern void g(int i = T()); }
5762 we should do the substitution when the template is
5763 instantiated. We handle the member function case in
5764 instantiate_class_template since the default arguments
5765 might refer to other members of the class. */
5767 && !PRIMARY_TEMPLATE_P (gen_tmpl)
5768 && !uses_template_parms (argvec))
5769 tsubst_default_arguments (r);
5772 /* Copy the list of befriending classes. */
5773 for (friends = &DECL_BEFRIENDING_CLASSES (r);
5775 friends = &TREE_CHAIN (*friends))
5777 *friends = copy_node (*friends);
5778 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
5779 args, /*complain=*/1,
5783 if (DECL_CONSTRUCTOR_P (r))
5785 maybe_retrofit_in_chrg (r);
5786 grok_ctor_properties (ctx, r);
5788 else if (DECL_OVERLOADED_OPERATOR_P (r))
5789 grok_op_properties (r, DECL_VIRTUAL_P (r), DECL_FRIEND_P (r));
5796 TREE_TYPE (r) = type;
5797 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5799 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
5800 DECL_INITIAL (r) = TREE_TYPE (r);
5802 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
5803 /*complain=*/1, in_decl);
5805 DECL_CONTEXT (r) = NULL_TREE;
5806 if (PROMOTE_PROTOTYPES
5807 && (TREE_CODE (type) == INTEGER_TYPE
5808 || TREE_CODE (type) == ENUMERAL_TYPE)
5809 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5810 DECL_ARG_TYPE (r) = integer_type_node;
5812 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
5813 /*complain=*/1, TREE_CHAIN (t));
5820 TREE_TYPE (r) = type;
5821 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5823 /* We don't have to set DECL_CONTEXT here; it is set by
5824 finish_member_declaration. */
5825 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
5826 /*complain=*/1, in_decl);
5827 TREE_CHAIN (r) = NULL_TREE;
5828 if (TREE_CODE (type) == VOID_TYPE)
5829 cp_error_at ("instantiation of `%D' as type void", r);
5837 = tsubst_copy (DECL_INITIAL (t), args, /*complain=*/1, in_decl);
5838 TREE_CHAIN (r) = NULL_TREE;
5843 if (DECL_IMPLICIT_TYPEDEF_P (t))
5845 /* For an implicit typedef, we just want the implicit
5846 typedef for the tsubst'd type. We've already got the
5847 tsubst'd type, as TYPE, so we just need it's associated
5849 r = TYPE_NAME (type);
5852 else if (!DECL_LANG_SPECIFIC (t))
5854 /* For a template type parameter, we don't have to do
5855 anything special. */
5856 r = TYPE_NAME (type);
5870 /* Nobody should be tsubst'ing into non-template variables. */
5871 my_friendly_assert (DECL_LANG_SPECIFIC (t)
5872 && DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5874 if (TYPE_P (CP_DECL_CONTEXT (t)))
5875 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5877 in_decl, /*entering_scope=*/1);
5879 /* Subsequent calls to pushdecl will fill this in. */
5882 /* Check to see if we already have this specialization. */
5883 tmpl = DECL_TI_TEMPLATE (t);
5884 gen_tmpl = most_general_template (tmpl);
5885 argvec = tsubst (DECL_TI_ARGS (t), args, /*complain=*/1, in_decl);
5887 spec = retrieve_specialization (gen_tmpl, argvec);
5889 spec = retrieve_local_specialization (gen_tmpl,
5890 current_function_decl);
5899 TREE_TYPE (r) = type;
5900 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5901 DECL_CONTEXT (r) = ctx;
5903 /* Don't try to expand the initializer until someone tries to use
5904 this variable; otherwise we run into circular dependencies. */
5905 DECL_INITIAL (r) = NULL_TREE;
5907 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
5909 /* For __PRETTY_FUNCTION__ we have to adjust the initializer. */
5910 if (DECL_PRETTY_FUNCTION_P (r))
5912 DECL_INITIAL (r) = tsubst (DECL_INITIAL (t),
5916 TREE_TYPE (r) = TREE_TYPE (DECL_INITIAL (r));
5919 /* Even if the original location is out of scope, the newly
5920 substituted one is not. */
5921 if (TREE_CODE (r) == VAR_DECL)
5922 DECL_DEAD_FOR_LOCAL (r) = 0;
5924 /* A static data member declaration is always marked external
5925 when it is declared in-class, even if an initializer is
5926 present. We mimic the non-template processing here. */
5928 DECL_EXTERNAL (r) = 1;
5930 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
5931 SET_DECL_IMPLICIT_INSTANTIATION (r);
5933 register_specialization (r, gen_tmpl, argvec);
5935 register_local_specialization (r, gen_tmpl,
5936 current_function_decl);
5938 TREE_CHAIN (r) = NULL_TREE;
5939 if (TREE_CODE (r) == VAR_DECL && TREE_CODE (type) == VOID_TYPE)
5940 cp_error_at ("instantiation of `%D' as type void", r);
5945 my_friendly_abort (0);
5948 /* Restore the file and line information. */
5949 lineno = saved_lineno;
5950 input_filename = saved_filename;
5955 /* Substitue into the ARG_TYPES of a function type. */
5958 tsubst_arg_types (arg_types, args, complain, in_decl)
5964 tree remaining_arg_types;
5967 if (!arg_types || arg_types == void_list_node)
5970 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
5971 args, complain, in_decl);
5972 if (remaining_arg_types == error_mark_node)
5973 return error_mark_node;
5975 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
5976 if (type == error_mark_node)
5977 return error_mark_node;
5979 /* Do array-to-pointer, function-to-pointer conversion, and ignore
5980 top-level qualifiers as required. */
5981 type = TYPE_MAIN_VARIANT (type_decays_to (type));
5983 /* Note that we do not substitute into default arguments here. The
5984 standard mandates that they be instantiated only when needed,
5985 which is done in build_over_call. */
5986 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
5987 remaining_arg_types);
5991 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
5992 *not* handle the exception-specification for FNTYPE, because the
5993 initial substitution of explicitly provided template parameters
5994 during argument deduction forbids substitution into the
5995 exception-specification:
5999 All references in the function type of the function template to the
6000 corresponding template parameters are replaced by the specified tem-
6001 plate argument values. If a substitution in a template parameter or
6002 in the function type of the function template results in an invalid
6003 type, type deduction fails. [Note: The equivalent substitution in
6004 exception specifications is done only when the function is instanti-
6005 ated, at which point a program is ill-formed if the substitution
6006 results in an invalid type.] */
6009 tsubst_function_type (t, args, complain, in_decl)
6019 /* The TYPE_CONTEXT is not used for function/method types. */
6020 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6022 /* Substitue the return type. */
6023 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6024 if (return_type == error_mark_node)
6025 return error_mark_node;
6027 /* Substitue the argument types. */
6028 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6030 if (arg_types == error_mark_node)
6031 return error_mark_node;
6033 /* Construct a new type node and return it. */
6034 if (TREE_CODE (t) == FUNCTION_TYPE)
6035 fntype = build_function_type (return_type, arg_types);
6038 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6039 if (! IS_AGGR_TYPE (r))
6043 Type deduction may fail for any of the following
6046 -- Attempting to create "pointer to member of T" when T
6047 is not a class type. */
6049 cp_error ("creating pointer to member function of non-class type `%T'",
6051 return error_mark_node;
6054 fntype = build_cplus_method_type (r, return_type, TREE_CHAIN
6057 fntype = build_qualified_type (fntype, TYPE_QUALS (t));
6058 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6063 /* Substitute into the PARMS of a call-declarator. */
6066 tsubst_call_declarator_parms (parms, args, complain, in_decl)
6076 if (!parms || parms == void_list_node)
6079 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6080 args, complain, in_decl);
6082 /* Figure out the type of this parameter. */
6083 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6085 /* Figure out the default argument as well. Note that we use
6086 tsubst_expr since the default argument is really an expression. */
6087 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6089 /* Chain this parameter on to the front of those we have already
6090 processed. We don't use hash_tree_cons because that function
6091 doesn't check TREE_PARMLIST. */
6092 new_parms = tree_cons (defarg, type, new_parms);
6094 /* And note that these are parameters. */
6095 TREE_PARMLIST (new_parms) = 1;
6100 /* Take the tree structure T and replace template parameters used
6101 therein with the argument vector ARGS. IN_DECL is an associated
6102 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6103 An appropriate error message is issued only if COMPLAIN is
6104 non-zero. Note that we must be relatively non-tolerant of
6105 extensions here, in order to preserve conformance; if we allow
6106 substitutions that should not be allowed, we may allow argument
6107 deductions that should not succeed, and therefore report ambiguous
6108 overload situations where there are none. In theory, we could
6109 allow the substitution, but indicate that it should have failed,
6110 and allow our caller to make sure that the right thing happens, but
6111 we don't try to do this yet.
6113 This function is used for dealing with types, decls and the like;
6114 for expressions, use tsubst_expr or tsubst_copy. */
6117 tsubst (t, args, complain, in_decl)
6124 if (t == NULL_TREE || t == error_mark_node
6125 || t == integer_type_node
6126 || t == void_type_node
6127 || t == char_type_node
6128 || TREE_CODE (t) == NAMESPACE_DECL)
6131 if (TREE_CODE (t) == IDENTIFIER_NODE)
6132 type = IDENTIFIER_TYPE_VALUE (t);
6134 type = TREE_TYPE (t);
6135 if (type == unknown_type_node)
6136 my_friendly_abort (42);
6138 if (type && TREE_CODE (t) != FUNCTION_DECL
6139 && TREE_CODE (t) != TYPENAME_TYPE
6140 && TREE_CODE (t) != TEMPLATE_DECL
6141 && TREE_CODE (t) != IDENTIFIER_NODE
6142 && TREE_CODE (t) != FUNCTION_TYPE
6143 && TREE_CODE (t) != METHOD_TYPE)
6144 type = tsubst (type, args, complain, in_decl);
6145 if (type == error_mark_node)
6146 return error_mark_node;
6149 return tsubst_decl (t, args, type, in_decl);
6151 switch (TREE_CODE (t))
6156 return tsubst_aggr_type (t, args, complain, in_decl,
6157 /*entering_scope=*/0);
6160 case IDENTIFIER_NODE:
6172 if (t == integer_type_node)
6175 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6176 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6180 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6182 max = tsubst_expr (omax, args, complain, in_decl);
6183 if (max == error_mark_node)
6184 return error_mark_node;
6186 /* See if we can reduce this expression to something simpler. */
6187 max = maybe_fold_nontype_arg (max);
6188 if (!processing_template_decl && TREE_READONLY_DECL_P (max))
6189 max = decl_constant_value (max);
6191 if (processing_template_decl
6192 /* When providing explicit arguments to a template
6193 function, but leaving some arguments for subsequent
6194 deduction, MAX may be template-dependent even if we're
6195 not PROCESSING_TEMPLATE_DECL. We still need to check for
6196 template parms, though; MAX won't be an INTEGER_CST for
6197 dynamic arrays, either. */
6198 || (TREE_CODE (max) != INTEGER_CST
6199 && uses_template_parms (max)))
6201 tree itype = make_node (INTEGER_TYPE);
6202 TYPE_MIN_VALUE (itype) = size_zero_node;
6203 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6208 if (integer_zerop (omax))
6210 /* Still allow an explicit array of size zero. */
6212 pedwarn ("creating array with size zero");
6214 else if (integer_zerop (max)
6215 || (TREE_CODE (max) == INTEGER_CST
6216 && INT_CST_LT (max, integer_zero_node)))
6220 Type deduction may fail for any of the following
6223 Attempting to create an array with a size that is
6224 zero or negative. */
6226 cp_error ("creating array with size zero (`%E')", max);
6228 return error_mark_node;
6231 return compute_array_index_type (NULL_TREE, max);
6234 case TEMPLATE_TYPE_PARM:
6235 case TEMPLATE_TEMPLATE_PARM:
6236 case TEMPLATE_PARM_INDEX:
6244 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6245 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6247 idx = TEMPLATE_TYPE_IDX (t);
6248 level = TEMPLATE_TYPE_LEVEL (t);
6252 idx = TEMPLATE_PARM_IDX (t);
6253 level = TEMPLATE_PARM_LEVEL (t);
6256 if (TREE_VEC_LENGTH (args) > 0)
6258 tree arg = NULL_TREE;
6260 levels = TMPL_ARGS_DEPTH (args);
6261 if (level <= levels)
6262 arg = TMPL_ARG (args, level, idx);
6264 if (arg == error_mark_node)
6265 return error_mark_node;
6266 else if (arg != NULL_TREE)
6268 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6270 my_friendly_assert (TYPE_P (arg), 0);
6271 return cp_build_qualified_type_real
6272 (arg, CP_TYPE_QUALS (arg) | CP_TYPE_QUALS (t),
6275 else if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6277 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6279 /* We are processing a type constructed from
6280 a template template parameter */
6281 tree argvec = tsubst (TYPE_TI_ARGS (t),
6282 args, complain, in_decl);
6283 if (argvec == error_mark_node)
6284 return error_mark_node;
6286 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6287 we are resolving nested-types in the signature of
6288 a member function templates.
6289 Otherwise ARG is a TEMPLATE_DECL and is the real
6290 template to be instantiated. */
6291 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6292 arg = TYPE_NAME (arg);
6294 r = lookup_template_class (DECL_NAME (arg),
6297 /*entering_scope=*/0);
6298 return cp_build_qualified_type_real (r,
6303 /* We are processing a template argument list. */
6311 my_friendly_abort (981018);
6314 /* This can happen during the attempted tsubst'ing in
6315 unify. This means that we don't yet have any information
6316 about the template parameter in question. */
6319 /* If we get here, we must have been looking at a parm for a
6320 more deeply nested template. Make a new version of this
6321 template parameter, but with a lower level. */
6322 switch (TREE_CODE (t))
6324 case TEMPLATE_TYPE_PARM:
6325 case TEMPLATE_TEMPLATE_PARM:
6327 TEMPLATE_TYPE_PARM_INDEX (r)
6328 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6330 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6331 TYPE_MAIN_VARIANT (r) = r;
6332 TYPE_POINTER_TO (r) = NULL_TREE;
6333 TYPE_REFERENCE_TO (r) = NULL_TREE;
6335 if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6336 && TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6338 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6340 if (argvec == error_mark_node)
6341 return error_mark_node;
6343 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6344 = tree_cons (TYPE_NAME (t), argvec, NULL_TREE);
6348 case TEMPLATE_PARM_INDEX:
6349 r = reduce_template_parm_level (t, type, levels);
6353 my_friendly_abort (0);
6361 tree purpose, value, chain, result;
6363 if (t == void_list_node)
6366 purpose = TREE_PURPOSE (t);
6369 purpose = tsubst (purpose, args, complain, in_decl);
6370 if (purpose == error_mark_node)
6371 return error_mark_node;
6373 value = TREE_VALUE (t);
6376 value = tsubst (value, args, complain, in_decl);
6377 if (value == error_mark_node)
6378 return error_mark_node;
6380 chain = TREE_CHAIN (t);
6381 if (chain && chain != void_type_node)
6383 chain = tsubst (chain, args, complain, in_decl);
6384 if (chain == error_mark_node)
6385 return error_mark_node;
6387 if (purpose == TREE_PURPOSE (t)
6388 && value == TREE_VALUE (t)
6389 && chain == TREE_CHAIN (t))
6391 result = hash_tree_cons (purpose, value, chain);
6392 TREE_PARMLIST (result) = TREE_PARMLIST (t);
6396 if (type != NULL_TREE)
6398 /* A binfo node. We always need to make a copy, of the node
6399 itself and of its BINFO_BASETYPES. */
6403 /* Make sure type isn't a typedef copy. */
6404 type = BINFO_TYPE (TYPE_BINFO (type));
6406 TREE_TYPE (t) = complete_type (type);
6407 if (IS_AGGR_TYPE (type))
6409 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6410 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6411 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6412 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6417 /* Otherwise, a vector of template arguments. */
6418 return tsubst_template_arg_vector (t, args, complain);
6421 case REFERENCE_TYPE:
6423 enum tree_code code;
6425 if (type == TREE_TYPE (t))
6428 code = TREE_CODE (t);
6433 Type deduction may fail for any of the following
6436 -- Attempting to create a pointer to reference type.
6437 -- Attempting to create a reference to a reference type or
6438 a reference to void. */
6439 if (TREE_CODE (type) == REFERENCE_TYPE
6440 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6442 static int last_line = 0;
6443 static char* last_file = 0;
6445 /* We keep track of the last time we issued this error
6446 message to avoid spewing a ton of messages during a
6447 single bad template instantiation. */
6448 if (complain && (last_line != lineno ||
6449 last_file != input_filename))
6451 if (TREE_CODE (type) == VOID_TYPE)
6452 cp_error ("forming reference to void");
6454 cp_error ("forming %s to reference type `%T'",
6455 (code == POINTER_TYPE) ? "pointer" : "reference",
6458 last_file = input_filename;
6461 return error_mark_node;
6463 else if (code == POINTER_TYPE)
6464 r = build_pointer_type (type);
6466 r = build_reference_type (type);
6467 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6469 /* Will this ever be needed for TYPE_..._TO values? */
6475 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6476 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6480 Type deduction may fail for any of the following
6483 -- Attempting to create "pointer to member of T" when T
6484 is not a class type. */
6486 cp_error ("creating pointer to member of non-class type `%T'",
6488 return error_mark_node;
6490 return build_offset_type (r, type);
6498 fntype = tsubst_function_type (t, args, complain, in_decl);
6499 if (fntype == error_mark_node)
6500 return error_mark_node;
6502 /* Substitue the exception specification. */
6503 raises = TYPE_RAISES_EXCEPTIONS (t);
6506 tree list = NULL_TREE;
6508 if (! TREE_VALUE (raises))
6511 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6513 tree spec = TREE_VALUE (raises);
6515 spec = tsubst (spec, args, complain, in_decl);
6516 if (spec == error_mark_node)
6518 list = add_exception_specifier (list, spec, complain);
6520 fntype = build_exception_variant (fntype, list);
6526 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6527 if (domain == error_mark_node)
6528 return error_mark_node;
6530 /* As an optimization, we avoid regenerating the array type if
6531 it will obviously be the same as T. */
6532 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6535 /* These checks should match the ones in grokdeclarator.
6539 The deduction may fail for any of the following reasons:
6541 -- Attempting to create an array with an element type that
6542 is void, a function type, or a reference type. */
6543 if (TREE_CODE (type) == VOID_TYPE
6544 || TREE_CODE (type) == FUNCTION_TYPE
6545 || TREE_CODE (type) == REFERENCE_TYPE)
6548 cp_error ("creating array of `%T'", type);
6549 return error_mark_node;
6552 r = build_cplus_array_type (type, domain);
6559 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6561 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain,
6564 if (e1 == error_mark_node || e2 == error_mark_node)
6565 return error_mark_node;
6567 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6573 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6575 if (e == error_mark_node)
6576 return error_mark_node;
6578 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6583 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6584 in_decl, /*entering_scope=*/1);
6585 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6588 if (ctx == error_mark_node || f == error_mark_node)
6589 return error_mark_node;
6591 if (!IS_AGGR_TYPE (ctx))
6594 cp_error ("`%T' is not a class, struct, or union type",
6596 return error_mark_node;
6598 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6600 /* Normally, make_typename_type does not require that the CTX
6601 have complete type in order to allow things like:
6603 template <class T> struct S { typename S<T>::X Y; };
6605 But, such constructs have already been resolved by this
6606 point, so here CTX really should have complete type, unless
6607 it's a partial instantiation. */
6608 ctx = complete_type (ctx);
6609 if (!COMPLETE_TYPE_P (ctx))
6612 incomplete_type_error (NULL_TREE, ctx);
6613 return error_mark_node;
6617 f = make_typename_type (ctx, f, complain);
6618 if (f == error_mark_node)
6620 return cp_build_qualified_type_real (f,
6622 | CP_TYPE_QUALS (t),
6628 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6630 if (e == error_mark_node)
6631 return error_mark_node;
6632 return make_pointer_declarator (type, e);
6637 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6639 if (e == error_mark_node)
6640 return error_mark_node;
6641 return make_reference_declarator (type, e);
6646 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6648 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain,
6650 if (e1 == error_mark_node || e2 == error_mark_node)
6651 return error_mark_node;
6653 return build_parse_node (ARRAY_REF, e1, e2, tsubst_expr);
6658 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6660 tree e2 = (tsubst_call_declarator_parms
6661 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6662 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6665 if (e1 == error_mark_node || e2 == error_mark_node
6666 || e3 == error_mark_node)
6667 return error_mark_node;
6669 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6674 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6676 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6677 if (e1 == error_mark_node || e2 == error_mark_node)
6678 return error_mark_node;
6680 return build_parse_node (TREE_CODE (t), e1, e2);
6685 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain,
6687 if (e1 == error_mark_node)
6688 return error_mark_node;
6690 return TREE_TYPE (e1);
6700 /* This code should match declare_hidden_char_array in
6702 name = (*decl_printable_name) (current_function_decl, 2);
6703 len = strlen (name) + 1;
6704 type = build_array_type (char_type_node,
6705 build_index_type (build_int_2 (len, 0)));
6706 str = build_string (len, name);
6707 TREE_TYPE (str) = type;
6712 sorry ("use of `%s' in template",
6713 tree_code_name [(int) TREE_CODE (t)]);
6714 return error_mark_node;
6718 /* Like tsubst, but deals with expressions. This function just replaces
6719 template parms; to finish processing the resultant expression, use
6723 tsubst_copy (t, args, complain, in_decl)
6728 enum tree_code code;
6731 if (t == NULL_TREE || t == error_mark_node)
6734 code = TREE_CODE (t);
6739 return do_identifier (DECL_NAME (t), 0, NULL_TREE);
6746 if (!DECL_CONTEXT (t))
6747 /* This is a global enumeration constant. */
6750 /* Unfortunately, we cannot just call lookup_name here.
6753 template <int I> int f() {
6755 struct S { void g() { E e = a; } };
6758 When we instantiate f<7>::S::g(), say, lookup_name is not
6759 clever enough to find f<7>::a. */
6761 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
6762 /*entering_scope=*/0);
6764 for (v = TYPE_VALUES (enum_type);
6767 if (TREE_PURPOSE (v) == DECL_NAME (t))
6768 return TREE_VALUE (v);
6770 /* We didn't find the name. That should never happen; if
6771 name-lookup found it during preliminary parsing, we
6772 should find it again here during instantiation. */
6773 my_friendly_abort (0);
6778 if (DECL_CONTEXT (t))
6782 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
6783 /*entering_scope=*/1);
6784 if (ctx != DECL_CONTEXT (t))
6785 return lookup_field (ctx, DECL_NAME (t), 0, 0);
6791 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
6792 t = tsubst (t, args, complain, in_decl);
6797 if (is_member_template (t))
6798 return tsubst (t, args, complain, in_decl);
6804 /* We must tsbust into a LOOKUP_EXPR in case the names to
6805 which it refers is a conversion operator; in that case the
6806 name will change. We avoid making unnecessary copies,
6809 tree id = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6811 if (id != TREE_OPERAND (t, 0))
6813 r = build_nt (LOOKUP_EXPR, id);
6814 LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t);
6822 case REINTERPRET_CAST_EXPR:
6823 case CONST_CAST_EXPR:
6824 case STATIC_CAST_EXPR:
6825 case DYNAMIC_CAST_EXPR:
6828 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6829 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6832 case PREDECREMENT_EXPR:
6833 case PREINCREMENT_EXPR:
6834 case POSTDECREMENT_EXPR:
6835 case POSTINCREMENT_EXPR:
6837 case TRUTH_NOT_EXPR:
6840 case CONVERT_EXPR: /* Unary + */
6849 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6850 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6855 case TRUNC_DIV_EXPR:
6857 case FLOOR_DIV_EXPR:
6858 case ROUND_DIV_EXPR:
6859 case EXACT_DIV_EXPR:
6861 case BIT_ANDTC_EXPR:
6864 case TRUNC_MOD_EXPR:
6865 case FLOOR_MOD_EXPR:
6866 case TRUTH_ANDIF_EXPR:
6867 case TRUTH_ORIF_EXPR:
6868 case TRUTH_AND_EXPR:
6889 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6890 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
6894 tree fn = TREE_OPERAND (t, 0);
6895 if (is_overloaded_fn (fn))
6896 fn = tsubst_copy (get_first_fn (fn), args, complain, in_decl);
6898 /* Sometimes FN is a LOOKUP_EXPR. */
6899 fn = tsubst_copy (fn, args, complain, in_decl);
6901 (code, fn, tsubst_copy (TREE_OPERAND (t, 1), args, complain,
6906 case METHOD_CALL_EXPR:
6908 tree name = TREE_OPERAND (t, 0);
6909 if (TREE_CODE (name) == BIT_NOT_EXPR)
6911 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6913 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6915 else if (TREE_CODE (name) == SCOPE_REF
6916 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
6918 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
6920 name = TREE_OPERAND (name, 1);
6921 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6923 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6924 name = build_nt (SCOPE_REF, base, name);
6927 name = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6929 (code, name, tsubst_copy (TREE_OPERAND (t, 1), args,
6931 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl),
6936 /* This processing should really occur in tsubst_expr, However,
6937 tsubst_expr does not recurse into expressions, since it
6938 assumes that there aren't any statements inside them.
6939 Instead, it simply calls build_expr_from_tree. So, we need
6940 to expand the STMT_EXPR here. */
6941 if (!processing_template_decl)
6943 tree stmt_expr = begin_stmt_expr ();
6944 tsubst_expr (STMT_EXPR_STMT (t), args,
6946 return finish_stmt_expr (stmt_expr);
6953 case PSEUDO_DTOR_EXPR:
6956 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6957 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
6958 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
6965 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6966 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
6967 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
6968 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
6975 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6976 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
6977 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
6978 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
6982 case TEMPLATE_ID_EXPR:
6984 /* Substituted template arguments */
6985 tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, complain,
6988 if (targs && TREE_CODE (targs) == TREE_LIST)
6991 for (chain = targs; chain; chain = TREE_CHAIN (chain))
6992 TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain));
6997 for (i = 0; i < TREE_VEC_LENGTH (targs); ++i)
6998 TREE_VEC_ELT (targs, i)
6999 = maybe_fold_nontype_arg (TREE_VEC_ELT (targs, i));
7002 return lookup_template_function
7003 (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), targs);
7008 tree purpose, value, chain;
7010 if (t == void_list_node)
7013 purpose = TREE_PURPOSE (t);
7015 purpose = tsubst_copy (purpose, args, complain, in_decl);
7016 value = TREE_VALUE (t);
7018 value = tsubst_copy (value, args, complain, in_decl);
7019 chain = TREE_CHAIN (t);
7020 if (chain && chain != void_type_node)
7021 chain = tsubst_copy (chain, args, complain, in_decl);
7022 if (purpose == TREE_PURPOSE (t)
7023 && value == TREE_VALUE (t)
7024 && chain == TREE_CHAIN (t))
7026 return tree_cons (purpose, value, chain);
7033 case TEMPLATE_TYPE_PARM:
7034 case TEMPLATE_TEMPLATE_PARM:
7035 case TEMPLATE_PARM_INDEX:
7037 case REFERENCE_TYPE:
7044 return tsubst (t, args, complain, in_decl);
7046 case IDENTIFIER_NODE:
7047 if (IDENTIFIER_TYPENAME_P (t)
7048 /* Make sure it's not just a variable named `__opr', for instance,
7049 which can occur in some existing code. */
7051 return build_typename_overload
7052 (tsubst (TREE_TYPE (t), args, complain, in_decl));
7059 (CONSTRUCTOR, tsubst (TREE_TYPE (t), args, complain, in_decl),
7060 NULL_TREE, tsubst_copy (CONSTRUCTOR_ELTS (t), args,
7061 complain, in_decl));
7062 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7067 return build_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7069 tsubst (TREE_TYPE (t), args, complain, in_decl));
7072 return tsubst (t, args, complain, in_decl);
7079 /* Like tsubst_copy, but also does semantic processing. */
7082 tsubst_expr (t, args, complain, in_decl)
7089 if (t == NULL_TREE || t == error_mark_node)
7092 if (processing_template_decl)
7093 return tsubst_copy (t, args, complain, in_decl);
7095 switch (TREE_CODE (t))
7099 finish_named_return_value
7100 (TREE_OPERAND (t, 0),
7101 tsubst_expr (TREE_OPERAND (t, 1), args, /*complain=*/1, in_decl));
7102 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7105 case CTOR_INITIALIZER:
7107 current_member_init_list
7108 = tsubst_expr_values (TREE_OPERAND (t, 0), args);
7109 current_base_init_list
7110 = tsubst_expr_values (TREE_OPERAND (t, 1), args);
7112 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7117 finish_return_stmt (tsubst_expr (RETURN_EXPR (t),
7118 args, complain, in_decl));
7123 finish_expr_stmt (tsubst_expr (EXPR_STMT_EXPR (t),
7124 args, complain, in_decl));
7133 decl = DECL_STMT_DECL (t);
7134 if (TREE_CODE (decl) == LABEL_DECL)
7135 finish_label_decl (DECL_NAME (decl));
7138 init = DECL_INITIAL (decl);
7139 decl = tsubst (decl, args, complain, in_decl);
7140 init = tsubst_expr (init, args, complain, in_decl);
7142 DECL_INITIAL (decl) = error_mark_node;
7143 /* By marking the declaration as instantiated, we avoid
7144 trying to instantiate it. Since instantiate_decl can't
7145 handle local variables, and since we've already done
7146 all that needs to be done, that's the right thing to
7148 if (TREE_CODE (decl) == VAR_DECL)
7149 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7150 maybe_push_decl (decl);
7151 cp_finish_decl (decl, init, NULL_TREE, 0);
7161 stmt = begin_for_stmt ();
7162 for (tmp = FOR_INIT_STMT (t); tmp; tmp = TREE_CHAIN (tmp))
7163 tsubst_expr (tmp, args, complain, in_decl);
7164 finish_for_init_stmt (stmt);
7165 finish_for_cond (tsubst_expr (FOR_COND (t), args,
7168 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7169 finish_for_expr (tmp, stmt);
7170 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7171 finish_for_stmt (tmp, stmt);
7178 stmt = begin_while_stmt ();
7179 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7180 args, complain, in_decl),
7182 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7183 finish_while_stmt (stmt);
7190 stmt = begin_do_stmt ();
7191 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7192 finish_do_body (stmt);
7193 finish_do_stmt (tsubst_expr (DO_COND (t), args,
7204 stmt = begin_if_stmt ();
7205 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7206 args, complain, in_decl),
7209 if (tmp = THEN_CLAUSE (t), tmp)
7211 tsubst_expr (tmp, args, complain, in_decl);
7212 finish_then_clause (stmt);
7215 if (tmp = ELSE_CLAUSE (t), tmp)
7217 begin_else_clause ();
7218 tsubst_expr (tmp, args, complain, in_decl);
7219 finish_else_clause (stmt);
7231 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7232 for (substmt = COMPOUND_BODY (t);
7233 substmt != NULL_TREE;
7234 substmt = TREE_CHAIN (substmt))
7235 tsubst_expr (substmt, args, complain, in_decl);
7236 return finish_compound_stmt (COMPOUND_STMT_NO_SCOPE (t), stmt);
7242 finish_break_stmt ();
7247 finish_continue_stmt ();
7255 stmt = begin_switch_stmt ();
7256 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7257 finish_switch_cond (val, stmt);
7258 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7259 finish_switch_stmt (val, stmt);
7265 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7266 tsubst_expr (CASE_HIGH (t), args, complain, in_decl));
7270 lineno = STMT_LINENO (t);
7271 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7276 t = GOTO_DESTINATION (t);
7277 if (TREE_CODE (t) != LABEL_DECL)
7278 /* Computed goto's must be tsubst'd into. On the other hand,
7279 non-computed gotos must not be; the identifier in question
7280 will have no binding. */
7281 t = tsubst_expr (t, args, complain, in_decl);
7284 finish_goto_stmt (t);
7289 finish_asm_stmt (ASM_CV_QUAL (t),
7290 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7291 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7292 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7293 tsubst_expr (ASM_CLOBBERS (t), args, complain,
7301 stmt = begin_try_block ();
7302 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7303 finish_cleanup_try_block (stmt);
7304 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7312 if (FN_TRY_BLOCK_P (t))
7313 stmt = begin_function_try_block ();
7315 stmt = begin_try_block ();
7317 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7319 if (FN_TRY_BLOCK_P (t))
7320 finish_function_try_block (stmt);
7322 finish_try_block (stmt);
7324 handler = TRY_HANDLERS (t);
7325 for (; handler; handler = TREE_CHAIN (handler))
7326 tsubst_expr (handler, args, complain, in_decl);
7327 if (FN_TRY_BLOCK_P (t))
7328 finish_function_handler_sequence (stmt);
7330 finish_handler_sequence (stmt);
7340 stmt = begin_handler ();
7341 if (HANDLER_PARMS (t))
7343 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7344 decl = tsubst (decl, args, complain, in_decl);
7345 /* Prevent instantiate_decl from trying to instantiate
7346 this variable. We've already done all that needs to be
7348 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7352 blocks = finish_handler_parms (decl, stmt);
7353 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7354 finish_handler (blocks, stmt);
7361 tsubst (t, args, complain, NULL_TREE);
7365 return build_expr_from_tree (tsubst_copy (t, args, complain, in_decl));
7370 /* Instantiate the indicated variable or function template TMPL with
7371 the template arguments in TARG_PTR. */
7374 instantiate_template (tmpl, targ_ptr)
7375 tree tmpl, targ_ptr;
7383 if (tmpl == error_mark_node)
7384 return error_mark_node;
7386 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
7388 /* Check to see if we already have this specialization. */
7389 spec = retrieve_specialization (tmpl, targ_ptr);
7390 if (spec != NULL_TREE)
7393 if (DECL_TEMPLATE_INFO (tmpl) && !DECL_TEMPLATE_SPECIALIZATION (tmpl))
7395 /* The TMPL is a partial instantiation. To get a full set of
7396 arguments we must add the arguments used to perform the
7397 partial instantiation. */
7398 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
7400 gen_tmpl = most_general_template (tmpl);
7402 /* Check to see if we already have this specialization. */
7403 spec = retrieve_specialization (gen_tmpl, targ_ptr);
7404 if (spec != NULL_TREE)
7410 len = DECL_NTPARMS (gen_tmpl);
7411 inner_args = innermost_args (targ_ptr);
7415 tree t = TREE_VEC_ELT (inner_args, i);
7418 tree nt = target_type (t);
7419 if (IS_AGGR_TYPE (nt) && decl_function_context (TYPE_MAIN_DECL (nt)))
7421 cp_error ("type `%T' composed from a local class is not a valid template-argument", t);
7422 cp_error (" trying to instantiate `%D'", gen_tmpl);
7423 fndecl = error_mark_node;
7429 /* substitute template parameters */
7430 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
7431 targ_ptr, /*complain=*/1, gen_tmpl);
7432 /* The DECL_TI_TEMPLATE should always be the immediate parent
7433 template, not the most general template. */
7434 DECL_TI_TEMPLATE (fndecl) = tmpl;
7436 if (flag_external_templates)
7437 add_pending_template (fndecl);
7443 /* Push the name of the class template into the scope of the instantiation. */
7446 overload_template_name (type)
7449 tree id = DECL_NAME (CLASSTYPE_TI_TEMPLATE (type));
7452 if (IDENTIFIER_CLASS_VALUE (id)
7453 && TREE_TYPE (IDENTIFIER_CLASS_VALUE (id)) == type)
7456 decl = build_decl (TYPE_DECL, id, type);
7457 SET_DECL_ARTIFICIAL (decl);
7458 pushdecl_class_level (decl);
7461 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
7462 arguments that are being used when calling it. TARGS is a vector
7463 into which the deduced template arguments are placed.
7465 Return zero for success, 2 for an incomplete match that doesn't resolve
7466 all the types, and 1 for complete failure. An error message will be
7467 printed only for an incomplete match.
7469 If FN is a conversion operator, RETURN_TYPE is the type desired as
7470 the result of the conversion operator.
7472 TPARMS is a vector of template parameters.
7474 The EXPLICIT_TARGS are explicit template arguments provided via a
7477 The parameter STRICT is one of:
7480 We are deducing arguments for a function call, as in
7484 We are deducing arguments for a conversion function, as in
7488 We are deducing arguments when calculating the partial
7489 ordering between specializations of function or class
7490 templates, as in [temp.func.order] and [temp.class.order],
7491 when doing an explicit instantiation as in [temp.explicit],
7492 when determining an explicit specialization as in
7493 [temp.expl.spec], or when taking the address of a function
7494 template, as in [temp.deduct.funcaddr].
7496 The other arguments are as for type_unification. */
7499 fn_type_unification (fn, explicit_targs, targs, args, return_type,
7501 tree fn, explicit_targs, targs, args, return_type;
7502 unification_kind_t strict;
7508 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
7510 fntype = TREE_TYPE (fn);
7515 The specified template arguments must match the template
7516 parameters in kind (i.e., type, nontype, template), and there
7517 must not be more arguments than there are parameters;
7518 otherwise type deduction fails.
7520 Nontype arguments must match the types of the corresponding
7521 nontype template parameters, or must be convertible to the
7522 types of the corresponding nontype parameters as specified in
7523 _temp.arg.nontype_, otherwise type deduction fails.
7525 All references in the function type of the function template
7526 to the corresponding template parameters are replaced by the
7527 specified template argument values. If a substitution in a
7528 template parameter or in the function type of the function
7529 template results in an invalid type, type deduction fails. */
7531 tree converted_args;
7534 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7535 explicit_targs, NULL_TREE, /*complain=*/0,
7536 /*require_all_arguments=*/0));
7537 if (converted_args == error_mark_node)
7540 fntype = tsubst (fntype, converted_args, /*complain=*/0, NULL_TREE);
7541 if (fntype == error_mark_node)
7544 /* Place the explicitly specified arguments in TARGS. */
7545 for (i = 0; i < TREE_VEC_LENGTH (targs); i++)
7546 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
7549 parms = TYPE_ARG_TYPES (fntype);
7551 if (DECL_CONV_FN_P (fn))
7553 /* This is a template conversion operator. Remove `this', since
7554 we could be comparing conversions from different classes. */
7555 parms = TREE_CHAIN (parms);
7556 args = TREE_CHAIN (args);
7557 my_friendly_assert (return_type != NULL_TREE, 20000227);
7562 /* We've been given a return type to match, prepend it. */
7563 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
7564 args = tree_cons (NULL_TREE, return_type, args);
7567 /* We allow incomplete unification without an error message here
7568 because the standard doesn't seem to explicitly prohibit it. Our
7569 callers must be ready to deal with unification failures in any
7571 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7572 targs, parms, args, /*subr=*/0,
7573 strict, /*allow_incomplete*/1);
7576 /* All is well so far. Now, check:
7580 When all template arguments have been deduced, all uses of
7581 template parameters in nondeduced contexts are replaced with
7582 the corresponding deduced argument values. If the
7583 substitution results in an invalid type, as described above,
7584 type deduction fails. */
7585 if (tsubst (TREE_TYPE (fn), targs, /*complain=*/0, NULL_TREE)
7592 /* Adjust types before performing type deduction, as described in
7593 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
7594 sections are symmetric. PARM is the type of a function parameter
7595 or the return type of the conversion function. ARG is the type of
7596 the argument passed to the call, or the type of the value
7597 intialized with the result of the conversion function. */
7600 maybe_adjust_types_for_deduction (strict, parm, arg)
7601 unification_kind_t strict;
7612 /* Swap PARM and ARG throughout the remainder of this
7613 function; the handling is precisely symmetric since PARM
7614 will initialize ARG rather than vice versa. */
7622 /* There is nothing to do in this case. */
7626 my_friendly_abort (0);
7629 if (TREE_CODE (*parm) != REFERENCE_TYPE)
7631 /* [temp.deduct.call]
7633 If P is not a reference type:
7635 --If A is an array type, the pointer type produced by the
7636 array-to-pointer standard conversion (_conv.array_) is
7637 used in place of A for type deduction; otherwise,
7639 --If A is a function type, the pointer type produced by
7640 the function-to-pointer standard conversion
7641 (_conv.func_) is used in place of A for type deduction;
7644 --If A is a cv-qualified type, the top level
7645 cv-qualifiers of A's type are ignored for type
7647 if (TREE_CODE (*arg) == ARRAY_TYPE)
7648 *arg = build_pointer_type (TREE_TYPE (*arg));
7649 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
7650 *arg = build_pointer_type (*arg);
7652 *arg = TYPE_MAIN_VARIANT (*arg);
7655 /* [temp.deduct.call]
7657 If P is a cv-qualified type, the top level cv-qualifiers
7658 of P's type are ignored for type deduction. If P is a
7659 reference type, the type referred to by P is used for
7661 *parm = TYPE_MAIN_VARIANT (*parm);
7662 if (TREE_CODE (*parm) == REFERENCE_TYPE)
7663 *parm = TREE_TYPE (*parm);
7666 /* Like type_unfication.
7668 If SUBR is 1, we're being called recursively (to unify the
7669 arguments of a function or method parameter of a function
7673 type_unification_real (tparms, targs, parms, args, subr,
7674 strict, allow_incomplete)
7675 tree tparms, targs, parms, args;
7677 unification_kind_t strict;
7678 int allow_incomplete;
7682 int ntparms = TREE_VEC_LENGTH (tparms);
7685 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
7686 my_friendly_assert (parms == NULL_TREE
7687 || TREE_CODE (parms) == TREE_LIST, 290);
7688 /* ARGS could be NULL (via a call from parse.y to
7689 build_x_function_call). */
7691 my_friendly_assert (TREE_CODE (args) == TREE_LIST, 291);
7692 my_friendly_assert (ntparms > 0, 292);
7697 sub_strict = UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_DERIVED;
7701 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
7705 sub_strict = UNIFY_ALLOW_NONE;
7709 my_friendly_abort (0);
7713 && parms != void_list_node
7715 && args != void_list_node)
7717 parm = TREE_VALUE (parms);
7718 parms = TREE_CHAIN (parms);
7719 arg = TREE_VALUE (args);
7720 args = TREE_CHAIN (args);
7722 if (arg == error_mark_node)
7724 if (arg == unknown_type_node)
7725 /* We can't deduce anything from this, but we might get all the
7726 template args from other function args. */
7729 /* Conversions will be performed on a function argument that
7730 corresponds with a function parameter that contains only
7731 non-deducible template parameters and explicitly specified
7732 template parameters. */
7733 if (! uses_template_parms (parm))
7738 type = TREE_TYPE (arg);
7745 if (strict == DEDUCE_EXACT)
7747 if (same_type_p (parm, type))
7751 /* It might work; we shouldn't check now, because we might
7752 get into infinite recursion. Overload resolution will
7761 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
7762 if (type_unknown_p (arg))
7764 /* [temp.deduct.type] A template-argument can be deduced from
7765 a pointer to function or pointer to member function
7766 argument if the set of overloaded functions does not
7767 contain function templates and at most one of a set of
7768 overloaded functions provides a unique match. */
7770 if (resolve_overloaded_unification
7771 (tparms, targs, parm, arg, strict, sub_strict)
7776 arg = TREE_TYPE (arg);
7780 maybe_adjust_types_for_deduction (strict, &parm, &arg);
7782 switch (unify (tparms, targs, parm, arg, sub_strict))
7790 /* Fail if we've reached the end of the parm list, and more args
7791 are present, and the parm list isn't variadic. */
7792 if (args && args != void_list_node && parms == void_list_node)
7794 /* Fail if parms are left and they don't have default values. */
7796 && parms != void_list_node
7797 && TREE_PURPOSE (parms) == NULL_TREE)
7800 for (i = 0; i < ntparms; i++)
7801 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
7803 if (!allow_incomplete)
7804 error ("incomplete type unification");
7810 /* Subroutine of type_unification_real. Args are like the variables at the
7811 call site. ARG is an overloaded function (or template-id); we try
7812 deducing template args from each of the overloads, and if only one
7813 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
7816 resolve_overloaded_unification (tparms, targs, parm, arg, strict,
7818 tree tparms, targs, parm, arg;
7819 unification_kind_t strict;
7822 tree tempargs = copy_node (targs);
7825 if (TREE_CODE (arg) == ADDR_EXPR)
7826 arg = TREE_OPERAND (arg, 0);
7828 if (TREE_CODE (arg) == COMPONENT_REF)
7829 /* Handle `&x' where `x' is some static or non-static member
7831 arg = TREE_OPERAND (arg, 1);
7833 if (TREE_CODE (arg) == OFFSET_REF)
7834 arg = TREE_OPERAND (arg, 1);
7836 /* Strip baselink information. */
7837 while (TREE_CODE (arg) == TREE_LIST)
7838 arg = TREE_VALUE (arg);
7840 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
7842 /* If we got some explicit template args, we need to plug them into
7843 the affected templates before we try to unify, in case the
7844 explicit args will completely resolve the templates in question. */
7846 tree expl_subargs = TREE_OPERAND (arg, 1);
7847 arg = TREE_OPERAND (arg, 0);
7849 for (; arg; arg = OVL_NEXT (arg))
7851 tree fn = OVL_CURRENT (arg);
7854 if (TREE_CODE (fn) != TEMPLATE_DECL)
7857 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
7861 elem = tsubst (TREE_TYPE (fn), subargs, /*complain=*/0,
7863 if (TREE_CODE (elem) == METHOD_TYPE)
7864 elem = build_ptrmemfunc_type (build_pointer_type (elem));
7865 good += try_one_overload (tparms, targs, tempargs, parm, elem,
7866 strict, sub_strict);
7870 else if (TREE_CODE (arg) == OVERLOAD)
7872 for (; arg; arg = OVL_NEXT (arg))
7874 tree type = TREE_TYPE (OVL_CURRENT (arg));
7875 if (TREE_CODE (type) == METHOD_TYPE)
7876 type = build_ptrmemfunc_type (build_pointer_type (type));
7877 good += try_one_overload (tparms, targs, tempargs, parm,
7879 strict, sub_strict);
7883 my_friendly_abort (981006);
7885 /* [temp.deduct.type] A template-argument can be deduced from a pointer
7886 to function or pointer to member function argument if the set of
7887 overloaded functions does not contain function templates and at most
7888 one of a set of overloaded functions provides a unique match.
7890 So if we found multiple possibilities, we return success but don't
7895 int i = TREE_VEC_LENGTH (targs);
7897 if (TREE_VEC_ELT (tempargs, i))
7898 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
7906 /* Subroutine of resolve_overloaded_unification; does deduction for a single
7907 overload. Fills TARGS with any deduced arguments, or error_mark_node if
7908 different overloads deduce different arguments for a given parm.
7909 Returns 1 on success. */
7912 try_one_overload (tparms, orig_targs, targs, parm, arg, strict,
7914 tree tparms, orig_targs, targs, parm, arg;
7915 unification_kind_t strict;
7922 /* [temp.deduct.type] A template-argument can be deduced from a pointer
7923 to function or pointer to member function argument if the set of
7924 overloaded functions does not contain function templates and at most
7925 one of a set of overloaded functions provides a unique match.
7927 So if this is a template, just return success. */
7929 if (uses_template_parms (arg))
7932 maybe_adjust_types_for_deduction (strict, &parm, &arg);
7934 /* We don't copy orig_targs for this because if we have already deduced
7935 some template args from previous args, unify would complain when we
7936 try to deduce a template parameter for the same argument, even though
7937 there isn't really a conflict. */
7938 nargs = TREE_VEC_LENGTH (targs);
7939 tempargs = make_tree_vec (nargs);
7941 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
7944 /* First make sure we didn't deduce anything that conflicts with
7945 explicitly specified args. */
7946 for (i = nargs; i--; )
7948 tree elt = TREE_VEC_ELT (tempargs, i);
7949 tree oldelt = TREE_VEC_ELT (orig_targs, i);
7951 if (elt == NULL_TREE)
7953 else if (uses_template_parms (elt))
7955 /* Since we're unifying against ourselves, we will fill in template
7956 args used in the function parm list with our own template parms.
7958 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
7961 else if (oldelt && ! template_args_equal (oldelt, elt))
7965 for (i = nargs; i--; )
7967 tree elt = TREE_VEC_ELT (tempargs, i);
7970 TREE_VEC_ELT (targs, i) = elt;
7976 /* PARM is a template class (perhaps with unbound template
7977 parameters). ARG is a fully instantiated type. If ARG can be
7978 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
7979 TARGS are as for unify. */
7982 try_class_unification (tparms, targs, parm, arg)
7991 if (!CLASSTYPE_TEMPLATE_INFO (arg)
7992 || CLASSTYPE_TI_TEMPLATE (arg) != CLASSTYPE_TI_TEMPLATE (parm))
7995 /* We need to make a new template argument vector for the call to
7996 unify. If we used TARGS, we'd clutter it up with the result of
7997 the attempted unification, even if this class didn't work out.
7998 We also don't want to commit ourselves to all the unifications
7999 we've already done, since unification is supposed to be done on
8000 an argument-by-argument basis. In other words, consider the
8001 following pathological case:
8003 template <int I, int J, int K>
8006 template <int I, int J>
8007 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
8009 template <int I, int J, int K>
8010 void f(S<I, J, K>, S<I, I, I>);
8019 Now, by the time we consider the unification involving `s2', we
8020 already know that we must have `f<0, 0, 0>'. But, even though
8021 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is not legal
8022 because there are two ways to unify base classes of S<0, 1, 2>
8023 with S<I, I, I>. If we kept the already deduced knowledge, we
8024 would reject the possibility I=1. */
8025 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
8026 i = unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
8027 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE);
8029 /* If unification failed, we're done. */
8036 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
8037 have alreay discovered to be satisfactory. ARG_BINFO is the binfo
8038 for the base class of ARG that we are currently examining. */
8041 get_template_base_recursive (tparms, targs, parm,
8042 arg_binfo, rval, flags)
8052 tree arg = BINFO_TYPE (arg_binfo);
8054 if (!(flags & GTB_IGNORE_TYPE))
8056 tree r = try_class_unification (tparms, targs,
8059 /* If there is more than one satisfactory baseclass, then:
8063 If they yield more than one possible deduced A, the type
8067 if (r && rval && !same_type_p (r, rval))
8068 return error_mark_node;
8073 binfos = BINFO_BASETYPES (arg_binfo);
8074 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
8076 /* Process base types. */
8077 for (i = 0; i < n_baselinks; i++)
8079 tree base_binfo = TREE_VEC_ELT (binfos, i);
8082 /* Skip this base, if we've already seen it. */
8083 if (BINFO_MARKED (base_binfo))
8087 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
8089 /* When searching for a non-virtual, we cannot mark virtually
8092 SET_BINFO_MARKED (base_binfo);
8094 rval = get_template_base_recursive (tparms, targs,
8098 GTB_VIA_VIRTUAL * this_virtual);
8100 /* If we discovered more than one matching base class, we can
8102 if (rval == error_mark_node)
8103 return error_mark_node;
8109 /* Given a template type PARM and a class type ARG, find the unique
8110 base type in ARG that is an instance of PARM. We do not examine
8111 ARG itself; only its base-classes. If there is no appropriate base
8112 class, return NULL_TREE. If there is more than one, return
8113 error_mark_node. PARM may be the type of a partial specialization,
8114 as well as a plain template type. Used by unify. */
8117 get_template_base (tparms, targs, parm, arg)
8126 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
8128 arg_binfo = TYPE_BINFO (complete_type (arg));
8129 rval = get_template_base_recursive (tparms, targs,
8134 /* Since get_template_base_recursive marks the bases classes, we
8135 must unmark them here. */
8136 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
8141 /* Returns the level of DECL, which declares a template parameter. */
8144 template_decl_level (decl)
8147 switch (TREE_CODE (decl))
8151 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
8154 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
8157 my_friendly_abort (0);
8162 /* Decide whether ARG can be unified with PARM, considering only the
8163 cv-qualifiers of each type, given STRICT as documented for unify.
8164 Returns non-zero iff the unification is OK on that basis.*/
8167 check_cv_quals_for_unify (strict, arg, parm)
8172 if (!(strict & UNIFY_ALLOW_MORE_CV_QUAL)
8173 && !at_least_as_qualified_p (arg, parm))
8176 if (!(strict & UNIFY_ALLOW_LESS_CV_QUAL)
8177 && !at_least_as_qualified_p (parm, arg))
8183 /* Takes parameters as for type_unification. Returns 0 if the
8184 type deduction suceeds, 1 otherwise. The parameter STRICT is a
8185 bitwise or of the following flags:
8188 Require an exact match between PARM and ARG.
8189 UNIFY_ALLOW_MORE_CV_QUAL:
8190 Allow the deduced ARG to be more cv-qualified than ARG.
8191 UNIFY_ALLOW_LESS_CV_QUAL:
8192 Allow the deduced ARG to be less cv-qualified than ARG.
8193 UNIFY_ALLOW_DERIVED:
8194 Allow the deduced ARG to be a template base class of ARG,
8195 or a pointer to a template base class of the type pointed to by
8197 UNIFY_ALLOW_INTEGER:
8198 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
8199 case for more information. */
8202 unify (tparms, targs, parm, arg, strict)
8203 tree tparms, targs, parm, arg;
8210 /* I don't think this will do the right thing with respect to types.
8211 But the only case I've seen it in so far has been array bounds, where
8212 signedness is the only information lost, and I think that will be
8214 while (TREE_CODE (parm) == NOP_EXPR)
8215 parm = TREE_OPERAND (parm, 0);
8217 if (arg == error_mark_node)
8219 if (arg == unknown_type_node)
8220 /* We can't deduce anything from this, but we might get all the
8221 template args from other function args. */
8224 /* If PARM uses template parameters, then we can't bail out here,
8225 even if ARG == PARM, since we won't record unifications for the
8226 template parameters. We might need them if we're trying to
8227 figure out which of two things is more specialized. */
8228 if (arg == parm && !uses_template_parms (parm))
8231 /* Immediately reject some pairs that won't unify because of
8232 cv-qualification mismatches. */
8233 if (TREE_CODE (arg) == TREE_CODE (parm)
8235 /* We check the cv-qualifiers when unifying with template type
8236 parameters below. We want to allow ARG `const T' to unify with
8237 PARM `T' for example, when computing which of two templates
8238 is more specialized, for example. */
8239 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
8240 && !check_cv_quals_for_unify (strict, arg, parm))
8243 switch (TREE_CODE (parm))
8246 /* In a type which contains a nested-name-specifier, template
8247 argument values cannot be deduced for template parameters used
8248 within the nested-name-specifier. */
8251 case TEMPLATE_TYPE_PARM:
8252 case TEMPLATE_TEMPLATE_PARM:
8253 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8255 if (TEMPLATE_TYPE_LEVEL (parm)
8256 != template_decl_level (tparm))
8257 /* The PARM is not one we're trying to unify. Just check
8258 to see if it matches ARG. */
8259 return (TREE_CODE (arg) == TREE_CODE (parm)
8260 && same_type_p (parm, arg)) ? 0 : 1;
8261 idx = TEMPLATE_TYPE_IDX (parm);
8262 targ = TREE_VEC_ELT (targs, idx);
8263 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
8265 /* Check for mixed types and values. */
8266 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
8267 && TREE_CODE (tparm) != TYPE_DECL)
8268 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
8269 && TREE_CODE (tparm) != TEMPLATE_DECL))
8272 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
8274 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm))
8276 /* We arrive here when PARM does not involve template
8279 /* ARG must be constructed from a template class. */
8280 if (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg))
8284 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
8285 tree parmvec = TYPE_TI_ARGS (parm);
8286 tree argvec = CLASSTYPE_TI_ARGS (arg);
8288 = DECL_INNERMOST_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (arg));
8291 /* The parameter and argument roles have to be switched here
8292 in order to handle default arguments properly. For example,
8293 template<template <class> class TT> void f(TT<int>)
8294 should be able to accept vector<int> which comes from
8295 template <class T, class Allocator = allocator>
8298 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
8302 /* Deduce arguments T, i from TT<T> or TT<i>.
8303 We check each element of PARMVEC and ARGVEC individually
8304 rather than the whole TREE_VEC since they can have
8305 different number of elements. */
8307 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
8309 tree t = TREE_VEC_ELT (parmvec, i);
8311 if (unify (tparms, targs, t,
8312 TREE_VEC_ELT (argvec, i),
8317 arg = CLASSTYPE_TI_TEMPLATE (arg);
8322 /* If PARM is `const T' and ARG is only `int', we don't have
8323 a match unless we are allowing additional qualification.
8324 If ARG is `const int' and PARM is just `T' that's OK;
8325 that binds `const int' to `T'. */
8326 if (!check_cv_quals_for_unify (strict | UNIFY_ALLOW_LESS_CV_QUAL,
8330 /* Consider the case where ARG is `const volatile int' and
8331 PARM is `const T'. Then, T should be `volatile int'. */
8333 cp_build_qualified_type_real (arg,
8335 & ~CP_TYPE_QUALS (parm),
8337 if (arg == error_mark_node)
8341 /* Simple cases: Value already set, does match or doesn't. */
8342 if (targ != NULL_TREE && same_type_p (targ, arg))
8347 /* Make sure that ARG is not a variable-sized array. (Note that
8348 were talking about variable-sized arrays (like `int[n]'),
8349 rather than arrays of unknown size (like `int[]').) We'll
8350 get very confused by such a type since the bound of the array
8351 will not be computable in an instantiation. Besides, such
8352 types are not allowed in ISO C++, so we can do as we please
8354 if (TREE_CODE (arg) == ARRAY_TYPE
8355 && !uses_template_parms (arg)
8356 && (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (arg)))
8360 TREE_VEC_ELT (targs, idx) = arg;
8363 case TEMPLATE_PARM_INDEX:
8364 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8366 if (TEMPLATE_PARM_LEVEL (parm)
8367 != template_decl_level (tparm))
8368 /* The PARM is not one we're trying to unify. Just check
8369 to see if it matches ARG. */
8370 return (TREE_CODE (arg) == TREE_CODE (parm)
8371 && cp_tree_equal (parm, arg) > 0) ? 0 : 1;
8373 idx = TEMPLATE_PARM_IDX (parm);
8374 targ = TREE_VEC_ELT (targs, idx);
8378 int i = (cp_tree_equal (targ, arg) > 0);
8384 my_friendly_abort (42);
8387 /* [temp.deduct.type] If, in the declaration of a function template
8388 with a non-type template-parameter, the non-type
8389 template-parameter is used in an expression in the function
8390 parameter-list and, if the corresponding template-argument is
8391 deduced, the template-argument type shall match the type of the
8392 template-parameter exactly, except that a template-argument
8393 deduced from an array bound may be of any integral type. */
8394 if (same_type_p (TREE_TYPE (arg), TREE_TYPE (parm)))
8396 else if ((strict & UNIFY_ALLOW_INTEGER)
8397 && (TREE_CODE (TREE_TYPE (parm)) == INTEGER_TYPE
8398 || TREE_CODE (TREE_TYPE (parm)) == BOOLEAN_TYPE))
8403 TREE_VEC_ELT (targs, idx) = arg;
8410 if (TREE_CODE (arg) != POINTER_TYPE)
8413 /* [temp.deduct.call]
8415 A can be another pointer or pointer to member type that can
8416 be converted to the deduced A via a qualification
8417 conversion (_conv.qual_).
8419 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
8420 This will allow for additional cv-qualification of the
8421 pointed-to types if appropriate. In general, this is a bit
8422 too generous; we are only supposed to allow qualification
8423 conversions and this method will allow an ARG of char** and
8424 a deduced ARG of const char**. However, overload
8425 resolution will subsequently invalidate the candidate, so
8426 this is probably OK. */
8427 sub_strict = strict;
8429 if (TREE_CODE (TREE_TYPE (arg)) != RECORD_TYPE)
8430 /* The derived-to-base conversion only persists through one
8431 level of pointers. */
8432 sub_strict &= ~UNIFY_ALLOW_DERIVED;
8434 return unify (tparms, targs, TREE_TYPE (parm),
8435 TREE_TYPE (arg), sub_strict);
8438 case REFERENCE_TYPE:
8439 if (TREE_CODE (arg) != REFERENCE_TYPE)
8441 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8445 if (TREE_CODE (arg) != ARRAY_TYPE)
8447 if ((TYPE_DOMAIN (parm) == NULL_TREE)
8448 != (TYPE_DOMAIN (arg) == NULL_TREE))
8450 if (TYPE_DOMAIN (parm) != NULL_TREE
8451 && unify (tparms, targs, TYPE_DOMAIN (parm),
8452 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
8454 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8462 if (TREE_CODE (arg) != TREE_CODE (parm))
8465 if (TREE_CODE (parm) == INTEGER_TYPE
8466 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
8468 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
8469 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
8470 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
8472 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
8473 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
8474 TYPE_MAX_VALUE (arg), UNIFY_ALLOW_INTEGER))
8477 /* We use the TYPE_MAIN_VARIANT since we have already
8478 checked cv-qualification at the top of the
8480 else if (!same_type_p (TYPE_MAIN_VARIANT (arg),
8481 TYPE_MAIN_VARIANT (parm)))
8484 /* As far as unification is concerned, this wins. Later checks
8485 will invalidate it if necessary. */
8488 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
8489 /* Type INTEGER_CST can come from ordinary constant template args. */
8491 while (TREE_CODE (arg) == NOP_EXPR)
8492 arg = TREE_OPERAND (arg, 0);
8494 if (TREE_CODE (arg) != INTEGER_CST)
8496 return !tree_int_cst_equal (parm, arg);
8501 if (TREE_CODE (arg) != TREE_VEC)
8503 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
8505 for (i = TREE_VEC_LENGTH (parm) - 1; i >= 0; i--)
8506 if (unify (tparms, targs,
8507 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
8515 if (TREE_CODE (arg) != TREE_CODE (parm))
8518 if (TYPE_PTRMEMFUNC_P (parm))
8520 if (!TYPE_PTRMEMFUNC_P (arg))
8523 return unify (tparms, targs,
8524 TYPE_PTRMEMFUNC_FN_TYPE (parm),
8525 TYPE_PTRMEMFUNC_FN_TYPE (arg),
8529 if (CLASSTYPE_TEMPLATE_INFO (parm))
8533 if (strict & UNIFY_ALLOW_DERIVED)
8535 /* First, we try to unify the PARM and ARG directly. */
8536 t = try_class_unification (tparms, targs,
8541 /* Fallback to the special case allowed in
8544 If P is a class, and P has the form
8545 template-id, then A can be a derived class of
8546 the deduced A. Likewise, if P is a pointer to
8547 a class of the form template-id, A can be a
8548 pointer to a derived class pointed to by the
8550 t = get_template_base (tparms, targs,
8553 if (! t || t == error_mark_node)
8557 else if (CLASSTYPE_TEMPLATE_INFO (arg)
8558 && (CLASSTYPE_TI_TEMPLATE (parm)
8559 == CLASSTYPE_TI_TEMPLATE (arg)))
8560 /* Perhaps PARM is something like S<U> and ARG is S<int>.
8561 Then, we should unify `int' and `U'. */
8564 /* There's no chance of unication succeeding. */
8567 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
8568 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
8570 else if (!same_type_p (TYPE_MAIN_VARIANT (parm),
8571 TYPE_MAIN_VARIANT (arg)))
8577 if (TREE_CODE (arg) != TREE_CODE (parm))
8580 if (unify (tparms, targs, TREE_TYPE (parm),
8581 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
8583 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
8584 TYPE_ARG_TYPES (arg), 1,
8588 if (TREE_CODE (arg) != OFFSET_TYPE)
8590 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
8591 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
8593 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8597 if (arg != decl_constant_value (parm))
8602 /* Matched cases are handled by the ARG == PARM test above. */
8606 if (TREE_CODE (TREE_OPERAND (parm, 1)) == INTEGER_CST)
8608 /* We handle this case specially, since it comes up with
8609 arrays. In particular, something like:
8611 template <int N> void f(int (&x)[N]);
8613 Here, we are trying to unify the range type, which
8614 looks like [0 ... (N - 1)]. */
8616 t1 = TREE_OPERAND (parm, 0);
8617 t2 = TREE_OPERAND (parm, 1);
8619 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
8621 return unify (tparms, targs, t1, t, strict);
8623 /* else fall through */
8626 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
8627 /* We're looking at an expression. This can happen with
8631 void foo(S<I>, S<I + 2>);
8633 This is a "nondeduced context":
8637 The nondeduced contexts are:
8639 --A type that is a template-id in which one or more of
8640 the template-arguments is an expression that references
8641 a template-parameter.
8643 In these cases, we assume deduction succeeded, but don't
8644 actually infer any unifications. */
8647 sorry ("use of `%s' in template type unification",
8648 tree_code_name [(int) TREE_CODE (parm)]);
8654 /* Called if RESULT is explicitly instantiated, or is a member of an
8655 explicitly instantiated class, or if using -frepo and the
8656 instantiation of RESULT has been assigned to this file. */
8659 mark_decl_instantiated (result, extern_p)
8663 if (TREE_CODE (result) != FUNCTION_DECL)
8664 /* The TREE_PUBLIC flag for function declarations will have been
8665 set correctly by tsubst. */
8666 TREE_PUBLIC (result) = 1;
8670 DECL_INTERFACE_KNOWN (result) = 1;
8671 DECL_NOT_REALLY_EXTERN (result) = 1;
8673 /* Always make artificials weak. */
8674 if (DECL_ARTIFICIAL (result) && flag_weak)
8675 comdat_linkage (result);
8676 /* For WIN32 we also want to put explicit instantiations in
8677 linkonce sections. */
8678 else if (TREE_PUBLIC (result))
8679 maybe_make_one_only (result);
8681 else if (TREE_CODE (result) == FUNCTION_DECL)
8685 /* Given two function templates PAT1 and PAT2, and explicit template
8686 arguments EXPLICIT_ARGS return:
8688 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
8689 -1 if PAT2 is more specialized than PAT1.
8690 0 if neither is more specialized. */
8693 more_specialized (pat1, pat2, explicit_args)
8694 tree pat1, pat2, explicit_args;
8700 = get_bindings_overload (pat1, DECL_TEMPLATE_RESULT (pat2), explicit_args);
8705 = get_bindings_overload (pat2, DECL_TEMPLATE_RESULT (pat1), explicit_args);
8712 /* Given two class template specialization list nodes PAT1 and PAT2, return:
8714 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
8715 -1 if PAT2 is more specialized than PAT1.
8716 0 if neither is more specialized. */
8719 more_specialized_class (pat1, pat2)
8725 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
8726 TREE_PURPOSE (pat2));
8730 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
8731 TREE_PURPOSE (pat1));
8738 /* Return the template arguments that will produce the function signature
8739 DECL from the function template FN, with the explicit template
8740 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
8741 also match. Return NULL_TREE if no satisfactory arguments could be
8745 get_bindings_real (fn, decl, explicit_args, check_rettype)
8746 tree fn, decl, explicit_args;
8749 int ntparms = DECL_NTPARMS (fn);
8750 tree targs = make_tree_vec (ntparms);
8752 tree decl_arg_types;
8755 /* Substitute the explicit template arguments into the type of DECL.
8756 The call to fn_type_unification will handle substitution into the
8758 decl_type = TREE_TYPE (decl);
8759 if (explicit_args && uses_template_parms (decl_type))
8762 tree converted_args;
8764 if (DECL_TEMPLATE_INFO (decl))
8765 tmpl = DECL_TI_TEMPLATE (decl);
8767 /* We can get here for some illegal specializations. */
8771 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
8772 explicit_args, NULL_TREE,
8774 /*require_all_arguments=*/0));
8775 if (converted_args == error_mark_node)
8778 decl_type = tsubst (decl_type, converted_args, /*complain=*/0,
8780 if (decl_type == error_mark_node)
8784 /* If FN is a static member function, adjust the type of DECL
8786 decl_arg_types = TYPE_ARG_TYPES (decl_type);
8787 if (DECL_STATIC_FUNCTION_P (fn)
8788 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
8789 decl_arg_types = TREE_CHAIN (decl_arg_types);
8791 i = fn_type_unification (fn, explicit_args, targs,
8793 (check_rettype || DECL_CONV_FN_P (fn)
8794 ? TREE_TYPE (decl_type) : NULL_TREE),
8803 /* For most uses, we want to check the return type. */
8806 get_bindings (fn, decl, explicit_args)
8807 tree fn, decl, explicit_args;
8809 return get_bindings_real (fn, decl, explicit_args, 1);
8812 /* But for more_specialized, we only care about the parameter types. */
8815 get_bindings_overload (fn, decl, explicit_args)
8816 tree fn, decl, explicit_args;
8818 return get_bindings_real (fn, decl, explicit_args, 0);
8821 /* Return the innermost template arguments that, when applied to a
8822 template specialization whose innermost template parameters are
8823 TPARMS, and whose specialization arguments are ARGS, yield the
8826 For example, suppose we have:
8828 template <class T, class U> struct S {};
8829 template <class T> struct S<T*, int> {};
8831 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
8832 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
8833 int}. The resulting vector will be {double}, indicating that `T'
8834 is bound to `double'. */
8837 get_class_bindings (tparms, parms, args)
8838 tree tparms, parms, args;
8840 int i, ntparms = TREE_VEC_LENGTH (tparms);
8841 tree vec = make_tree_vec (ntparms);
8843 args = innermost_args (args);
8845 if (unify (tparms, vec, parms, args, UNIFY_ALLOW_NONE))
8848 for (i = 0; i < ntparms; ++i)
8849 if (! TREE_VEC_ELT (vec, i))
8855 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
8856 Pick the most specialized template, and return the corresponding
8857 instantiation, or if there is no corresponding instantiation, the
8858 template itself. EXPLICIT_ARGS is any template arguments explicity
8859 mentioned in a template-id. If there is no most specialized
8860 tempalte, error_mark_node is returned. If there are no templates
8861 at all, NULL_TREE is returned. */
8864 most_specialized_instantiation (instantiations, explicit_args)
8865 tree instantiations;
8871 if (!instantiations)
8874 champ = instantiations;
8875 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
8877 fate = more_specialized (TREE_VALUE (champ),
8878 TREE_VALUE (fn), explicit_args);
8885 fn = TREE_CHAIN (fn);
8887 return error_mark_node;
8893 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
8895 fate = more_specialized (TREE_VALUE (champ),
8896 TREE_VALUE (fn), explicit_args);
8898 return error_mark_node;
8901 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
8904 /* Return the most specialized of the list of templates in FNS that can
8905 produce an instantiation matching DECL, given the explicit template
8906 arguments EXPLICIT_ARGS. */
8909 most_specialized (fns, decl, explicit_args)
8910 tree fns, decl, explicit_args;
8912 tree candidates = NULL_TREE;
8915 for (fn = fns; fn; fn = TREE_CHAIN (fn))
8917 tree candidate = TREE_VALUE (fn);
8919 args = get_bindings (candidate, decl, explicit_args);
8921 candidates = tree_cons (NULL_TREE, candidate, candidates);
8924 return most_specialized_instantiation (candidates, explicit_args);
8927 /* If DECL is a specialization of some template, return the most
8928 general such template. For example, given:
8930 template <class T> struct S { template <class U> void f(U); };
8932 if TMPL is `template <class U> void S<int>::f(U)' this will return
8933 the full template. This function will not trace past partial
8934 specializations, however. For example, given in addition:
8936 template <class T> struct S<T*> { template <class U> void f(U); };
8938 if TMPL is `template <class U> void S<int*>::f(U)' this will return
8939 `template <class T> template <class U> S<T*>::f(U)'. */
8942 most_general_template (decl)
8945 while (DECL_TEMPLATE_INFO (decl)
8946 && !(TREE_CODE (decl) == TEMPLATE_DECL
8947 && DECL_TEMPLATE_SPECIALIZATION (decl))
8948 /* The DECL_TI_TEMPLATE can be a LOOKUP_EXPR or
8949 IDENTIFIER_NODE in some cases. (See cp-tree.h for
8951 && TREE_CODE (DECL_TI_TEMPLATE (decl)) == TEMPLATE_DECL)
8952 decl = DECL_TI_TEMPLATE (decl);
8957 /* Return the most specialized of the class template specializations
8958 of TMPL which can produce an instantiation matching ARGS, or
8959 error_mark_node if the choice is ambiguous. */
8962 most_specialized_class (tmpl, args)
8966 tree list = NULL_TREE;
8971 tmpl = most_general_template (tmpl);
8972 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
8975 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
8978 list = decl_tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
8979 TREE_TYPE (list) = TREE_TYPE (t);
8989 for (; t; t = TREE_CHAIN (t))
8991 fate = more_specialized_class (champ, t);
9000 return error_mark_node;
9006 for (t = list; t && t != champ; t = TREE_CHAIN (t))
9008 fate = more_specialized_class (champ, t);
9010 return error_mark_node;
9016 /* called from the parser. */
9019 do_decl_instantiation (declspecs, declarator, storage)
9020 tree declspecs, declarator, storage;
9022 tree decl = grokdeclarator (declarator, declspecs, NORMAL, 0, NULL_TREE);
9023 tree result = NULL_TREE;
9027 /* An error ocurred, for which grokdeclarator has already issued
9028 an appropriate message. */
9030 else if (! DECL_LANG_SPECIFIC (decl))
9032 cp_error ("explicit instantiation of non-template `%#D'", decl);
9035 else if (TREE_CODE (decl) == VAR_DECL)
9037 /* There is an asymmetry here in the way VAR_DECLs and
9038 FUNCTION_DECLs are handled by grokdeclarator. In the case of
9039 the latter, the DECL we get back will be marked as a
9040 template instantiation, and the appropriate
9041 DECL_TEMPLATE_INFO will be set up. This does not happen for
9042 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
9043 should handle VAR_DECLs as it currently handles
9045 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, 0);
9046 if (result && TREE_CODE (result) != VAR_DECL)
9048 cp_error ("no matching template for `%D' found", result);
9052 else if (TREE_CODE (decl) != FUNCTION_DECL)
9054 cp_error ("explicit instantiation of `%#D'", decl);
9060 /* Check for various error cases. Note that if the explicit
9061 instantiation is legal the RESULT will currently be marked as an
9062 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
9063 until we get here. */
9065 if (DECL_TEMPLATE_SPECIALIZATION (result))
9069 No program shall both explicitly instantiate and explicitly
9070 specialize a template. */
9071 cp_pedwarn ("explicit instantiation of `%#D' after", result);
9072 cp_pedwarn_at ("explicit specialization here", result);
9075 else if (DECL_EXPLICIT_INSTANTIATION (result))
9079 No program shall explicitly instantiate any template more
9082 We check DECL_INTERFACE_KNOWN so as not to complain when the first
9083 instantiation was `extern' and the second is not, and EXTERN_P for
9084 the opposite case. If -frepo, chances are we already got marked
9085 as an explicit instantion because of the repo file. */
9086 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
9087 cp_pedwarn ("duplicate explicit instantiation of `%#D'", result);
9089 /* If we've already instantiated the template, just return now. */
9090 if (DECL_INTERFACE_KNOWN (result))
9093 else if (!DECL_IMPLICIT_INSTANTIATION (result))
9095 cp_error ("no matching template for `%D' found", result);
9098 else if (!DECL_TEMPLATE_INFO (result))
9100 cp_pedwarn ("explicit instantiation of non-template `%#D'", result);
9104 if (flag_external_templates)
9107 if (storage == NULL_TREE)
9109 else if (storage == ridpointers[(int) RID_EXTERN])
9112 cp_pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
9116 cp_error ("storage class `%D' applied to template instantiation",
9119 SET_DECL_EXPLICIT_INSTANTIATION (result);
9120 mark_decl_instantiated (result, extern_p);
9121 repo_template_instantiated (result, extern_p);
9123 instantiate_decl (result, /*defer_ok=*/1);
9127 mark_class_instantiated (t, extern_p)
9131 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
9132 SET_CLASSTYPE_INTERFACE_KNOWN (t);
9133 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
9134 CLASSTYPE_VTABLE_NEEDS_WRITING (t) = ! extern_p;
9135 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
9138 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
9139 rest_of_type_compilation (t, 1);
9144 do_type_instantiation (t, storage)
9151 if (TREE_CODE (t) == TYPE_DECL)
9154 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
9156 cp_error ("explicit instantiation of non-template type `%T'", t);
9162 /* With -fexternal-templates, explicit instantiations are treated the same
9163 as implicit ones. */
9164 if (flag_external_templates)
9167 if (!COMPLETE_TYPE_P (t))
9169 cp_error ("explicit instantiation of `%#T' before definition of template",
9174 if (storage != NULL_TREE)
9177 cp_pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
9178 IDENTIFIER_POINTER (storage));
9180 if (storage == ridpointers[(int) RID_INLINE])
9182 else if (storage == ridpointers[(int) RID_EXTERN])
9184 else if (storage == ridpointers[(int) RID_STATIC])
9188 cp_error ("storage class `%D' applied to template instantiation",
9194 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
9198 No program shall both explicitly instantiate and explicitly
9199 specialize a template. */
9200 cp_error ("explicit instantiation of `%#T' after", t);
9201 cp_error_at ("explicit specialization here", t);
9204 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
9208 No program shall explicitly instantiate any template more
9211 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
9212 was `extern'. If EXTERN_P then the second is. If -frepo, chances
9213 are we already got marked as an explicit instantion because of the
9214 repo file. All these cases are OK. */
9215 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository)
9216 cp_pedwarn ("duplicate explicit instantiation of `%#T'", t);
9218 /* If we've already instantiated the template, just return now. */
9219 if (!CLASSTYPE_INTERFACE_ONLY (t))
9223 mark_class_instantiated (t, extern_p);
9224 repo_template_instantiated (t, extern_p);
9232 /* In contrast to implicit instantiation, where only the
9233 declarations, and not the definitions, of members are
9234 instantiated, we have here:
9238 The explicit instantiation of a class template specialization
9239 implies the instantiation of all of its members not
9240 previously explicitly specialized in the translation unit
9241 containing the explicit instantiation.
9243 Of course, we can't instantiate member template classes, since
9244 we don't have any arguments for them. Note that the standard
9245 is unclear on whether the instatiation of the members are
9246 *explicit* instantiations or not. We choose to be generous,
9247 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
9248 the explicit instantiation of a class where some of the members
9249 have no definition in the current translation unit. */
9252 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
9253 if (TREE_CODE (tmp) == FUNCTION_DECL
9254 && DECL_TEMPLATE_INSTANTIATION (tmp))
9256 mark_decl_instantiated (tmp, extern_p);
9257 repo_template_instantiated (tmp, extern_p);
9259 instantiate_decl (tmp, /*defer_ok=*/1);
9262 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
9263 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
9265 mark_decl_instantiated (tmp, extern_p);
9266 repo_template_instantiated (tmp, extern_p);
9268 instantiate_decl (tmp, /*defer_ok=*/1);
9271 for (tmp = CLASSTYPE_TAGS (t); tmp; tmp = TREE_CHAIN (tmp))
9272 if (IS_AGGR_TYPE (TREE_VALUE (tmp))
9273 && !uses_template_parms (CLASSTYPE_TI_ARGS (TREE_VALUE (tmp))))
9274 do_type_instantiation (TYPE_MAIN_DECL (TREE_VALUE (tmp)), storage);
9278 /* Given a function DECL, which is a specialization of TMPL, modify
9279 DECL to be a re-instantiation of TMPL with the same template
9280 arguments. TMPL should be the template into which tsubst'ing
9281 should occur for DECL, not the most general template.
9283 One reason for doing this is a scenario like this:
9286 void f(const T&, int i);
9288 void g() { f(3, 7); }
9291 void f(const T& t, const int i) { }
9293 Note that when the template is first instantiated, with
9294 instantiate_template, the resulting DECL will have no name for the
9295 first parameter, and the wrong type for the second. So, when we go
9296 to instantiate the DECL, we regenerate it. */
9299 regenerate_decl_from_template (decl, tmpl)
9309 args = DECL_TI_ARGS (decl);
9310 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
9312 /* Unregister the specialization so that when we tsubst we will not
9313 just return DECL. We don't have to unregister DECL from TMPL
9314 because if would only be registered there if it were a partial
9315 instantiation of a specialization, which it isn't: it's a full
9317 gen_tmpl = most_general_template (tmpl);
9318 unregistered = unregister_specialization (decl, gen_tmpl);
9320 /* If the DECL was not unregistered then something peculiar is
9321 happening: we created a specialization but did not call
9322 register_specialization for it. */
9323 my_friendly_assert (unregistered, 0);
9325 if (TREE_CODE (decl) == VAR_DECL)
9326 /* Make sure that we can see identifiers, and compute access
9327 correctly, for the class members used in the declaration of
9328 this static variable. */
9329 pushclass (DECL_CONTEXT (decl), 2);
9331 /* Do the substitution to get the new declaration. */
9332 new_decl = tsubst (code_pattern, args, /*complain=*/1, NULL_TREE);
9334 if (TREE_CODE (decl) == VAR_DECL)
9336 /* Set up DECL_INITIAL, since tsubst doesn't. */
9337 DECL_INITIAL (new_decl) =
9338 tsubst_expr (DECL_INITIAL (code_pattern), args,
9339 /*complain=*/1, DECL_TI_TEMPLATE (decl));
9340 /* Pop the class context we pushed above. */
9343 else if (TREE_CODE (decl) == FUNCTION_DECL)
9345 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
9347 DECL_INITIAL (new_decl) = error_mark_node;
9348 /* And don't complain about a duplicate definition. */
9349 DECL_INITIAL (decl) = NULL_TREE;
9352 /* The immediate parent of the new template is still whatever it was
9353 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
9354 general template. We also reset the DECL_ASSEMBLER_NAME since
9355 tsubst always calculates the name as if the function in question
9356 were really a template instance, and sometimes, with friend
9357 functions, this is not so. See tsubst_friend_function for
9359 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
9360 DECL_ASSEMBLER_NAME (new_decl) = DECL_ASSEMBLER_NAME (decl);
9361 DECL_RTL (new_decl) = DECL_RTL (decl);
9363 /* Call duplicate decls to merge the old and new declarations. */
9364 duplicate_decls (new_decl, decl);
9366 /* Now, re-register the specialization. */
9367 register_specialization (decl, gen_tmpl, args);
9370 /* Produce the definition of D, a _DECL generated from a template. If
9371 DEFER_OK is non-zero, then we don't have to actually do the
9372 instantiation now; we just have to do it sometime. */
9375 instantiate_decl (d, defer_ok)
9379 tree tmpl = DECL_TI_TEMPLATE (d);
9380 tree args = DECL_TI_ARGS (d);
9385 int pattern_defined;
9387 char *file = input_filename;
9389 /* This function should only be used to instantiate templates for
9390 functions and static member variables. */
9391 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
9392 || TREE_CODE (d) == VAR_DECL, 0);
9394 if (DECL_TEMPLATE_INSTANTIATED (d))
9395 /* D has already been instantiated. It might seem reasonable to
9396 check whether or not D is an explict instantiation, and, if so,
9397 stop here. But when an explicit instantiation is deferred
9398 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
9399 is set, even though we still need to do the instantiation. */
9402 /* If we already have a specialization of this declaration, then
9403 there's no reason to instantiate it. Note that
9404 retrieve_specialization gives us both instantiations and
9405 specializations, so we must explicitly check
9406 DECL_TEMPLATE_SPECIALIZATION. */
9407 gen_tmpl = most_general_template (tmpl);
9408 spec = retrieve_specialization (gen_tmpl, args);
9409 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
9412 /* This needs to happen before any tsubsting. */
9413 if (! push_tinst_level (d))
9416 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
9417 for the instantiation. This is not always the most general
9418 template. Consider, for example:
9421 struct S { template <class U> void f();
9422 template <> void f<int>(); };
9424 and an instantiation of S<double>::f<int>. We want TD to be the
9425 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
9428 /* An instantiation cannot have a definition, so we need a
9429 more general template. */
9430 DECL_TEMPLATE_INSTANTIATION (td)
9431 /* We must also deal with friend templates. Given:
9433 template <class T> struct S {
9434 template <class U> friend void f() {};
9437 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
9438 so far as the language is concerned, but that's still
9439 where we get the pattern for the instantiation from. On
9440 ther hand, if the definition comes outside the class, say:
9442 template <class T> struct S {
9443 template <class U> friend void f();
9445 template <class U> friend void f() {}
9447 we don't need to look any further. That's what the check for
9448 DECL_INITIAL is for. */
9449 || (TREE_CODE (d) == FUNCTION_DECL
9450 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (td)
9451 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (td)));
9454 /* The present template, TD, should not be a definition. If it
9455 were a definition, we should be using it! Note that we
9456 cannot restructure the loop to just keep going until we find
9457 a template with a definition, since that might go too far if
9458 a specialization was declared, but not defined. */
9459 my_friendly_assert (!(TREE_CODE (d) == VAR_DECL
9460 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (td))),
9463 /* Fetch the more general template. */
9464 td = DECL_TI_TEMPLATE (td);
9467 code_pattern = DECL_TEMPLATE_RESULT (td);
9469 if (TREE_CODE (d) == FUNCTION_DECL)
9470 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
9472 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
9474 push_to_top_level ();
9475 lineno = DECL_SOURCE_LINE (d);
9476 input_filename = DECL_SOURCE_FILE (d);
9478 if (pattern_defined)
9480 repo_template_used (d);
9482 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
9484 if (flag_alt_external_templates)
9486 if (interface_unknown)
9487 warn_if_unknown_interface (d);
9489 else if (DECL_INTERFACE_KNOWN (code_pattern))
9491 DECL_INTERFACE_KNOWN (d) = 1;
9492 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
9495 warn_if_unknown_interface (code_pattern);
9499 import_export_decl (d);
9502 /* Reject all external templates except inline functions. */
9503 if (DECL_INTERFACE_KNOWN (d)
9504 && ! DECL_NOT_REALLY_EXTERN (d)
9505 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d)))
9508 /* We need to set up DECL_INITIAL regardless of pattern_defined if
9509 the variable is a static const initialized in the class body. */
9510 if (TREE_CODE (d) == VAR_DECL
9511 && TREE_READONLY (d)
9512 && DECL_INITIAL (d) == NULL_TREE
9513 && DECL_INITIAL (code_pattern) != NULL_TREE)
9515 /* Defer all other templates, unless we have been explicitly
9516 forbidden from doing so. We restore the source position here
9517 because it's used by add_pending_template. */
9518 else if (! pattern_defined || defer_ok)
9521 input_filename = file;
9523 if (at_eof && !pattern_defined
9524 && DECL_EXPLICIT_INSTANTIATION (d))
9527 The definition of a non-exported function template, a
9528 non-exported member function template, or a non-exported
9529 member function or static data member of a class template
9530 shall be present in every translation unit in which it is
9531 explicitly instantiated. */
9532 cp_error ("explicit instantiation of `%D' but no definition available",
9535 add_pending_template (d);
9539 /* We're now committed to instantiating this template. Mark it as
9540 instantiated so that recursive calls to instantiate_decl do not
9541 try to instantiate it again. */
9542 DECL_TEMPLATE_INSTANTIATED (d) = 1;
9544 /* Regenerate the declaration in case the template has been modified
9545 by a subsequent redeclaration. */
9546 regenerate_decl_from_template (d, td);
9548 /* We already set the file and line above. Reset them now in case
9549 they changed as a result of calling regenerate_decl_from_template. */
9550 lineno = DECL_SOURCE_LINE (d);
9551 input_filename = DECL_SOURCE_FILE (d);
9553 if (TREE_CODE (d) == VAR_DECL)
9555 DECL_IN_AGGR_P (d) = 0;
9556 if (DECL_INTERFACE_KNOWN (d))
9557 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
9560 DECL_EXTERNAL (d) = 1;
9561 DECL_NOT_REALLY_EXTERN (d) = 1;
9563 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
9565 else if (TREE_CODE (d) == FUNCTION_DECL)
9567 /* Set up context. */
9568 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
9569 store_parm_decls ();
9571 /* We already set up __FUNCTION__, etc., so we don't want to do
9573 current_function_name_declared = 1;
9575 /* Substitute into the body of the function. */
9576 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
9577 /*complain=*/1, tmpl);
9579 /* Finish the function. */
9580 expand_body (finish_function (0));
9583 /* We're not deferring instantiation any more. */
9584 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
9588 input_filename = file;
9590 pop_from_top_level ();
9596 /* Run through the list of templates that we wish we could
9597 instantiate, and instantiate any we can. */
9600 instantiate_pending_templates ()
9603 int instantiated_something = 0;
9610 t = &pending_templates;
9613 tree srcloc = TREE_PURPOSE (*t);
9614 tree instantiation = TREE_VALUE (*t);
9616 input_filename = SRCLOC_FILE (srcloc);
9617 lineno = SRCLOC_LINE (srcloc);
9619 if (TYPE_P (instantiation))
9623 if (!COMPLETE_TYPE_P (instantiation))
9625 instantiate_class_template (instantiation);
9626 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
9627 for (fn = TYPE_METHODS (instantiation);
9629 fn = TREE_CHAIN (fn))
9630 if (! DECL_ARTIFICIAL (fn))
9631 instantiate_decl (fn, /*defer_ok=*/0);
9632 if (COMPLETE_TYPE_P (instantiation))
9634 instantiated_something = 1;
9639 if (COMPLETE_TYPE_P (instantiation))
9640 /* If INSTANTIATION has been instantiated, then we don't
9641 need to consider it again in the future. */
9642 *t = TREE_CHAIN (*t);
9644 t = &TREE_CHAIN (*t);
9648 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
9649 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
9651 instantiation = instantiate_decl (instantiation,
9653 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
9655 instantiated_something = 1;
9660 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
9661 || DECL_TEMPLATE_INSTANTIATED (instantiation))
9662 /* If INSTANTIATION has been instantiated, then we don't
9663 need to consider it again in the future. */
9664 *t = TREE_CHAIN (*t);
9666 t = &TREE_CHAIN (*t);
9671 /* Go through the things that are template instantiations if we are
9672 using guiding declarations. */
9673 t = &maybe_templates;
9680 fn = TREE_VALUE (*t);
9682 if (DECL_INITIAL (fn))
9683 /* If the FN is already defined, then it was either already
9684 instantiated or, even though guiding declarations were
9685 allowed, a non-template definition was provided. */
9689 template = TREE_PURPOSE (*t);
9690 args = get_bindings (template, fn, NULL_TREE);
9691 fn = instantiate_template (template, args);
9692 instantiate_decl (fn, /*defer_ok=*/0);
9696 /* Remove this entry from the chain. */
9697 *t = TREE_CHAIN (*t);
9699 maybe_template_tail = t;
9703 return instantiated_something;
9706 /* Substitute ARGVEC into T, which is a TREE_LIST. In particular, it
9707 is an initializer list: the TREE_PURPOSEs are DECLs, and the
9708 TREE_VALUEs are initializer values. Used by instantiate_decl. */
9711 tsubst_expr_values (t, argvec)
9714 tree first = NULL_TREE;
9717 for (; t; t = TREE_CHAIN (t))
9719 tree pur = tsubst_copy (TREE_PURPOSE (t), argvec,
9720 /*complain=*/1, NULL_TREE);
9721 tree val = tsubst_expr (TREE_VALUE (t), argvec, /*complain=*/1,
9723 *p = build_tree_list (pur, val);
9724 p = &TREE_CHAIN (*p);
9729 /* D is an undefined function declaration in the presence of templates with
9730 the same name, listed in FNS. If one of them can produce D as an
9731 instantiation, remember this so we can instantiate it at EOF if D has
9732 not been defined by that time. */
9735 add_maybe_template (d, fns)
9740 if (DECL_MAYBE_TEMPLATE (d))
9743 t = most_specialized (fns, d, NULL_TREE);
9746 if (t == error_mark_node)
9748 cp_error ("ambiguous template instantiation for `%D'", d);
9752 *maybe_template_tail = tree_cons (t, d, NULL_TREE);
9753 maybe_template_tail = &TREE_CHAIN (*maybe_template_tail);
9754 DECL_MAYBE_TEMPLATE (d) = 1;
9757 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
9760 set_current_access_from_decl (decl)
9763 if (TREE_PRIVATE (decl))
9764 current_access_specifier = access_private_node;
9765 else if (TREE_PROTECTED (decl))
9766 current_access_specifier = access_protected_node;
9768 current_access_specifier = access_public_node;
9771 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
9772 is the instantiation (which should have been created with
9773 start_enum) and ARGS are the template arguments to use. */
9776 tsubst_enum (tag, newtag, args)
9783 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
9787 /* Note that in a template enum, the TREE_VALUE is the
9788 CONST_DECL, not the corresponding INTEGER_CST. */
9789 value = tsubst_expr (DECL_INITIAL (TREE_VALUE (e)),
9790 args, /*complain=*/1,
9793 /* Give this enumeration constant the correct access. */
9794 set_current_access_from_decl (TREE_VALUE (e));
9796 /* Actually build the enumerator itself. */
9797 build_enumerator (TREE_PURPOSE (e), value, newtag);
9800 finish_enum (newtag);
9803 /* Set the DECL_ASSEMBLER_NAME for DECL, which is a FUNCTION_DECL that
9804 is either an instantiation or specialization of a template
9808 set_mangled_name_for_template_decl (decl)
9811 tree saved_namespace;
9812 tree context = NULL_TREE;
9821 my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0);
9822 my_friendly_assert (DECL_TEMPLATE_INFO (decl) != NULL_TREE, 0);
9824 /* The names of template functions must be mangled so as to indicate
9825 what template is being specialized with what template arguments.
9826 For example, each of the following three functions must get
9827 different mangled names:
9830 template <> void f<7>(int);
9831 template <> void f<8>(int); */
9833 targs = DECL_TI_ARGS (decl);
9834 if (uses_template_parms (targs))
9835 /* This DECL is for a partial instantiation. There's no need to
9836 mangle the name of such an entity. */
9839 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9840 tparms = DECL_TEMPLATE_PARMS (tmpl);
9841 parm_depth = TMPL_PARMS_DEPTH (tparms);
9843 /* There should be as many levels of arguments as there are levels
9845 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
9847 /* We now compute the PARMS and RET_TYPE to give to
9848 build_decl_overload_real. The PARMS and RET_TYPE are the
9849 parameter and return types of the template, after all but the
9850 innermost template arguments have been substituted, not the
9851 parameter and return types of the function DECL. For example,
9854 template <class T> T f(T);
9856 both PARMS and RET_TYPE should be `T' even if DECL is `int f(int)'.
9857 A more subtle example is:
9859 template <class T> struct S { template <class U> void f(T, U); }
9861 Here, if DECL is `void S<int>::f(int, double)', PARMS should be
9862 {int, U}. Thus, the args that we want to subsitute into the
9863 return and parameter type for the function are those in TARGS,
9864 with the innermost level omitted. */
9865 fn_type = TREE_TYPE (tmpl);
9866 if (DECL_STATIC_FUNCTION_P (decl))
9867 context = DECL_CONTEXT (decl);
9869 if (parm_depth == 1)
9870 /* No substitution is necessary. */
9877 /* Replace the innermost level of the TARGS with NULL_TREEs to
9878 let tsubst know not to subsitute for those parameters. */
9879 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
9880 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
9881 SET_TMPL_ARGS_LEVEL (partial_args, i,
9882 TMPL_ARGS_LEVEL (targs, i));
9883 SET_TMPL_ARGS_LEVEL (partial_args,
9884 TMPL_ARGS_DEPTH (targs),
9885 make_tree_vec (DECL_NTPARMS (tmpl)));
9887 /* Now, do the (partial) substitution to figure out the
9888 appropriate function type. */
9889 fn_type = tsubst (fn_type, partial_args, /*complain=*/1, NULL_TREE);
9890 if (DECL_STATIC_FUNCTION_P (decl))
9891 context = tsubst (context, partial_args, /*complain=*/1, NULL_TREE);
9893 /* Substitute into the template parameters to obtain the real
9894 innermost set of parameters. This step is important if the
9895 innermost set of template parameters contains value
9896 parameters whose types depend on outer template parameters. */
9897 TREE_VEC_LENGTH (partial_args)--;
9898 tparms = tsubst_template_parms (tparms, partial_args, /*complain=*/1);
9901 /* Now, get the innermost parameters and arguments, and figure out
9902 the parameter and return types. */
9903 tparms = INNERMOST_TEMPLATE_PARMS (tparms);
9904 targs = innermost_args (targs);
9905 ret_type = TREE_TYPE (fn_type);
9906 parm_types = TYPE_ARG_TYPES (fn_type);
9908 /* For a static member function, we generate a fake `this' pointer,
9909 for the purposes of mangling. This indicates of which class the
9910 function is a member. Because of:
9914 There shall not be a static and a nonstatic member function
9915 with the same name and the same parameter types
9917 we don't have to worry that this will result in a clash with a
9918 non-static member function. */
9919 if (DECL_STATIC_FUNCTION_P (decl))
9920 parm_types = hash_tree_chain (build_pointer_type (context), parm_types);
9922 /* There should be the same number of template parameters as
9923 template arguments. */
9924 my_friendly_assert (TREE_VEC_LENGTH (tparms) == TREE_VEC_LENGTH (targs),
9927 /* If the template is in a namespace, we need to put that into the
9928 mangled name. Unfortunately, build_decl_overload_real does not
9929 get the decl to mangle, so it relies on the current
9930 namespace. Therefore, we set that here temporarily. */
9931 my_friendly_assert (DECL_P (decl), 980702);
9932 saved_namespace = current_namespace;
9933 current_namespace = CP_DECL_CONTEXT (decl);
9935 /* Actually set the DCL_ASSEMBLER_NAME. */
9936 DECL_ASSEMBLER_NAME (decl)
9937 = build_decl_overload_real (DECL_NAME (decl), parm_types, ret_type,
9939 DECL_FUNCTION_MEMBER_P (decl)
9940 + DECL_CONSTRUCTOR_P (decl));
9942 /* Restore the previously active namespace. */
9943 current_namespace = saved_namespace;