1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, 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". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
143 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
144 static void check_specialization_scope (void);
145 static tree process_partial_specialization (tree);
146 static void set_current_access_from_decl (tree);
147 static void check_default_tmpl_args (tree, tree, int, int);
148 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
149 static tree get_template_base (tree, tree, tree, tree);
150 static tree try_class_unification (tree, tree, tree, tree);
151 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
153 static tree determine_specialization (tree, tree, tree *, int, int);
154 static int template_args_equal (tree, tree);
155 static void tsubst_default_arguments (tree);
156 static tree for_each_template_parm_r (tree *, int *, void *);
157 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
158 static void copy_default_args_to_explicit_spec (tree);
159 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
160 static int eq_local_specializations (const void *, const void *);
161 static bool dependent_type_p_r (tree);
162 static tree tsubst (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
166 /* Make the current scope suitable for access checking when we are
167 processing T. T can be FUNCTION_DECL for instantiated function
168 template, or VAR_DECL for static member variable (need by
169 instantiate_decl). */
172 push_access_scope (tree t)
174 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
175 || TREE_CODE (t) == VAR_DECL);
177 if (DECL_FRIEND_CONTEXT (t))
178 push_nested_class (DECL_FRIEND_CONTEXT (t));
179 else if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
271 This function is guaranteed to return 0 if passed NULL_TREE so
272 that, for example, `template_class_depth (current_class_type)' is
276 template_class_depth_real (tree type, int count_specializations)
281 type && TREE_CODE (type) != NAMESPACE_DECL;
282 type = (TREE_CODE (type) == FUNCTION_DECL)
283 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
285 if (TREE_CODE (type) != FUNCTION_DECL)
287 if (CLASSTYPE_TEMPLATE_INFO (type)
288 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
289 && ((count_specializations
290 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
291 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
296 if (DECL_TEMPLATE_INFO (type)
297 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
298 && ((count_specializations
299 && DECL_TEMPLATE_SPECIALIZATION (type))
300 || uses_template_parms (DECL_TI_ARGS (type))))
308 /* Returns the template nesting level of the indicated class TYPE.
309 Like template_class_depth_real, but instantiations do not count in
313 template_class_depth (tree type)
315 return template_class_depth_real (type, /*count_specializations=*/0);
318 /* Returns 1 if processing DECL as part of do_pending_inlines
319 needs us to push template parms. */
322 inline_needs_template_parms (tree decl)
324 if (! DECL_TEMPLATE_INFO (decl))
327 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
328 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
331 /* Subroutine of maybe_begin_member_template_processing.
332 Push the template parms in PARMS, starting from LEVELS steps into the
333 chain, and ending at the beginning, since template parms are listed
337 push_inline_template_parms_recursive (tree parmlist, int levels)
339 tree parms = TREE_VALUE (parmlist);
343 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
345 ++processing_template_decl;
346 current_template_parms
347 = tree_cons (size_int (processing_template_decl),
348 parms, current_template_parms);
349 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
351 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
353 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
355 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
356 gcc_assert (DECL_P (parm));
358 switch (TREE_CODE (parm))
367 /* Make a CONST_DECL as is done in process_template_parm.
368 It is ugly that we recreate this here; the original
369 version built in process_template_parm is no longer
371 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
373 DECL_ARTIFICIAL (decl) = 1;
374 TREE_CONSTANT (decl) = 1;
375 TREE_INVARIANT (decl) = 1;
376 TREE_READONLY (decl) = 1;
377 DECL_INITIAL (decl) = DECL_INITIAL (parm);
378 SET_DECL_TEMPLATE_PARM_P (decl);
389 /* Restore the template parameter context for a member template or
390 a friend template defined in a class definition. */
393 maybe_begin_member_template_processing (tree decl)
398 if (inline_needs_template_parms (decl))
400 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
401 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
403 if (DECL_TEMPLATE_SPECIALIZATION (decl))
406 parms = TREE_CHAIN (parms);
409 push_inline_template_parms_recursive (parms, levels);
412 /* Remember how many levels of template parameters we pushed so that
413 we can pop them later. */
414 if (!inline_parm_levels)
415 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
416 if (inline_parm_levels_used == inline_parm_levels->num_elements)
417 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
418 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
419 ++inline_parm_levels_used;
422 /* Undo the effects of maybe_begin_member_template_processing. */
425 maybe_end_member_template_processing (void)
429 if (!inline_parm_levels_used)
432 --inline_parm_levels_used;
434 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
437 --processing_template_decl;
438 current_template_parms = TREE_CHAIN (current_template_parms);
443 /* Return a new template argument vector which contains all of ARGS,
444 but has as its innermost set of arguments the EXTRA_ARGS. */
447 add_to_template_args (tree args, tree extra_args)
454 extra_depth = TMPL_ARGS_DEPTH (extra_args);
455 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
457 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
458 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
460 for (j = 1; j <= extra_depth; ++j, ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
466 /* Like add_to_template_args, but only the outermost ARGS are added to
467 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
468 (EXTRA_ARGS) levels are added. This function is used to combine
469 the template arguments from a partial instantiation with the
470 template arguments used to attain the full instantiation from the
471 partial instantiation. */
474 add_outermost_template_args (tree args, tree extra_args)
478 /* If there are more levels of EXTRA_ARGS than there are ARGS,
479 something very fishy is going on. */
480 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
482 /* If *all* the new arguments will be the EXTRA_ARGS, just return
484 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
487 /* For the moment, we make ARGS look like it contains fewer levels. */
488 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
490 new_args = add_to_template_args (args, extra_args);
492 /* Now, we restore ARGS to its full dimensions. */
493 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
498 /* Return the N levels of innermost template arguments from the ARGS. */
501 get_innermost_template_args (tree args, int n)
509 /* If N is 1, just return the innermost set of template arguments. */
511 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
513 /* If we're not removing anything, just return the arguments we were
515 extra_levels = TMPL_ARGS_DEPTH (args) - n;
516 gcc_assert (extra_levels >= 0);
517 if (extra_levels == 0)
520 /* Make a new set of arguments, not containing the outer arguments. */
521 new_args = make_tree_vec (n);
522 for (i = 1; i <= n; ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i,
524 TMPL_ARGS_LEVEL (args, i + extra_levels));
529 /* We've got a template header coming up; push to a new level for storing
533 begin_template_parm_list (void)
535 /* We use a non-tag-transparent scope here, which causes pushtag to
536 put tags in this scope, rather than in the enclosing class or
537 namespace scope. This is the right thing, since we want
538 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
539 global template class, push_template_decl handles putting the
540 TEMPLATE_DECL into top-level scope. For a nested template class,
543 template <class T> struct S1 {
544 template <class T> struct S2 {};
547 pushtag contains special code to call pushdecl_with_scope on the
548 TEMPLATE_DECL for S2. */
549 begin_scope (sk_template_parms, NULL);
550 ++processing_template_decl;
551 ++processing_template_parmlist;
552 note_template_header (0);
555 /* This routine is called when a specialization is declared. If it is
556 invalid to declare a specialization here, an error is reported. */
559 check_specialization_scope (void)
561 tree scope = current_scope ();
565 An explicit specialization shall be declared in the namespace of
566 which the template is a member, or, for member templates, in the
567 namespace of which the enclosing class or enclosing class
568 template is a member. An explicit specialization of a member
569 function, member class or static data member of a class template
570 shall be declared in the namespace of which the class template
572 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
573 error ("explicit specialization in non-namespace scope %qD", scope);
577 In an explicit specialization declaration for a member of a class
578 template or a member template that appears in namespace scope,
579 the member template and some of its enclosing class templates may
580 remain unspecialized, except that the declaration shall not
581 explicitly specialize a class member template if its enclosing
582 class templates are not explicitly specialized as well. */
583 if (current_template_parms)
584 error ("enclosing class templates are not explicitly specialized");
587 /* We've just seen template <>. */
590 begin_specialization (void)
592 begin_scope (sk_template_spec, NULL);
593 note_template_header (1);
594 check_specialization_scope ();
597 /* Called at then end of processing a declaration preceded by
601 end_specialization (void)
604 reset_specialization ();
607 /* Any template <>'s that we have seen thus far are not referring to a
608 function specialization. */
611 reset_specialization (void)
613 processing_specialization = 0;
614 template_header_count = 0;
617 /* We've just seen a template header. If SPECIALIZATION is nonzero,
618 it was of the form template <>. */
621 note_template_header (int specialization)
623 processing_specialization = specialization;
624 template_header_count++;
627 /* We're beginning an explicit instantiation. */
630 begin_explicit_instantiation (void)
632 gcc_assert (!processing_explicit_instantiation);
633 processing_explicit_instantiation = true;
638 end_explicit_instantiation (void)
640 gcc_assert (processing_explicit_instantiation);
641 processing_explicit_instantiation = false;
644 /* An explicit specialization or partial specialization TMPL is being
645 declared. Check that the namespace in which the specialization is
646 occurring is permissible. Returns false iff it is invalid to
647 specialize TMPL in the current namespace. */
650 check_specialization_namespace (tree tmpl)
652 tree tpl_ns = decl_namespace_context (tmpl);
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template is
663 if (is_associated_namespace (current_namespace, tpl_ns))
664 /* Same or super-using namespace. */
668 pedwarn ("specialization of %qD in different namespace", tmpl);
669 pedwarn (" from definition of %q+#D", tmpl);
674 /* SPEC is an explicit instantiation. Check that it is valid to
675 perform this explicit instantiation in the current namespace. */
678 check_explicit_instantiation_namespace (tree spec)
682 /* DR 275: An explicit instantiation shall appear in an enclosing
683 namespace of its template. */
684 ns = decl_namespace_context (spec);
685 if (!is_ancestor (current_namespace, ns))
686 pedwarn ("explicit instantiation of %qD in namespace %qD "
687 "(which does not enclose namespace %qD)",
688 spec, current_namespace, ns);
691 /* The TYPE is being declared. If it is a template type, that means it
692 is a partial specialization. Do appropriate error-checking. */
695 maybe_process_partial_specialization (tree type)
699 if (type == error_mark_node)
702 context = TYPE_CONTEXT (type);
704 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
706 /* This is for ordinary explicit specialization and partial
707 specialization of a template class such as:
709 template <> class C<int>;
713 template <class T> class C<T*>;
715 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
717 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
718 && !COMPLETE_TYPE_P (type))
720 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
721 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
722 if (processing_template_decl)
723 push_template_decl (TYPE_MAIN_DECL (type));
725 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
726 error ("specialization of %qT after instantiation", type);
728 else if (CLASS_TYPE_P (type)
729 && !CLASSTYPE_USE_TEMPLATE (type)
730 && CLASSTYPE_TEMPLATE_INFO (type)
731 && context && CLASS_TYPE_P (context)
732 && CLASSTYPE_TEMPLATE_INFO (context))
734 /* This is for an explicit specialization of member class
735 template according to [temp.expl.spec/18]:
737 template <> template <class U> class C<int>::D;
739 The context `C<int>' must be an implicit instantiation.
740 Otherwise this is just a member class template declared
743 template <> class C<int> { template <class U> class D; };
744 template <> template <class U> class C<int>::D;
746 In the first case, `C<int>::D' is a specialization of `C<T>::D'
747 while in the second case, `C<int>::D' is a primary template
748 and `C<T>::D' may not exist. */
750 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
751 && !COMPLETE_TYPE_P (type))
755 if (current_namespace
756 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
758 pedwarn ("specializing %q#T in different namespace", type);
759 pedwarn (" from definition of %q+#D",
760 CLASSTYPE_TI_TEMPLATE (type));
763 /* Check for invalid specialization after instantiation:
765 template <> template <> class C<int>::D<int>;
766 template <> template <class U> class C<int>::D; */
768 for (t = DECL_TEMPLATE_INSTANTIATIONS
769 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
770 t; t = TREE_CHAIN (t))
771 if (TREE_VALUE (t) != type
772 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
773 error ("specialization %qT after instantiation %qT",
774 type, TREE_VALUE (t));
776 /* Mark TYPE as a specialization. And as a result, we only
777 have one level of template argument for the innermost
779 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
780 CLASSTYPE_TI_ARGS (type)
781 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
784 else if (processing_specialization)
785 error ("explicit specialization of non-template %qT", type);
788 /* Returns nonzero if we can optimize the retrieval of specializations
789 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
790 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
793 optimize_specialization_lookup_p (tree tmpl)
795 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
796 && DECL_CLASS_SCOPE_P (tmpl)
797 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
799 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
800 /* The optimized lookup depends on the fact that the
801 template arguments for the member function template apply
802 purely to the containing class, which is not true if the
803 containing class is an explicit or partial
805 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
806 && !DECL_MEMBER_TEMPLATE_P (tmpl)
807 && !DECL_CONV_FN_P (tmpl)
808 /* It is possible to have a template that is not a member
809 template and is not a member of a template class:
811 template <typename T>
812 struct S { friend A::f(); };
814 Here, the friend function is a template, but the context does
815 not have template information. The optimized lookup relies
816 on having ARGS be the template arguments for both the class
817 and the function template. */
818 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
821 /* Retrieve the specialization (in the sense of [temp.spec] - a
822 specialization is either an instantiation or an explicit
823 specialization) of TMPL for the given template ARGS. If there is
824 no such specialization, return NULL_TREE. The ARGS are a vector of
825 arguments, or a vector of vectors of arguments, in the case of
826 templates with more than one level of parameters.
828 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
829 then we search for a partial specialization matching ARGS. This
830 parameter is ignored if TMPL is not a class template. */
833 retrieve_specialization (tree tmpl, tree args,
834 bool class_specializations_p)
836 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
838 /* There should be as many levels of arguments as there are
839 levels of parameters. */
840 gcc_assert (TMPL_ARGS_DEPTH (args)
841 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
843 if (optimize_specialization_lookup_p (tmpl))
846 tree class_specialization;
847 VEC(tree,gc) *methods;
851 /* The template arguments actually apply to the containing
852 class. Find the class specialization with those
854 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
856 = retrieve_specialization (class_template, args,
857 /*class_specializations_p=*/false);
858 if (!class_specialization)
860 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
861 for the specialization. */
862 idx = class_method_index_for_fn (class_specialization, tmpl);
865 /* Iterate through the methods with the indicated name, looking
866 for the one that has an instance of TMPL. */
867 methods = CLASSTYPE_METHOD_VEC (class_specialization);
868 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
870 tree fn = OVL_CURRENT (fns);
871 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
881 /* Class templates store their instantiations on the
882 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
883 DECL_TEMPLATE_SPECIALIZATIONS list. */
884 if (!class_specializations_p
885 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
886 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
888 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
890 /* Iterate through the list until we find a matching template. */
891 while (*sp != NULL_TREE)
895 if (comp_template_args (TREE_PURPOSE (spec), args))
897 /* Use the move-to-front heuristic to speed up future
901 *sp = TREE_CHAIN (*sp);
902 TREE_CHAIN (spec) = *head;
905 return TREE_VALUE (spec);
907 sp = &TREE_CHAIN (spec);
914 /* Like retrieve_specialization, but for local declarations. */
917 retrieve_local_specialization (tree tmpl)
919 tree spec = htab_find_with_hash (local_specializations, tmpl,
920 htab_hash_pointer (tmpl));
921 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
924 /* Returns nonzero iff DECL is a specialization of TMPL. */
927 is_specialization_of (tree decl, tree tmpl)
931 if (TREE_CODE (decl) == FUNCTION_DECL)
935 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
941 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
943 for (t = TREE_TYPE (decl);
945 t = CLASSTYPE_USE_TEMPLATE (t)
946 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
947 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
954 /* Returns nonzero iff DECL is a specialization of friend declaration
955 FRIEND according to [temp.friend]. */
958 is_specialization_of_friend (tree decl, tree friend)
960 bool need_template = true;
963 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
964 || TREE_CODE (decl) == TYPE_DECL);
966 /* For [temp.friend/6] when FRIEND is an ordinary member function
967 of a template class, we want to check if DECL is a specialization
969 if (TREE_CODE (friend) == FUNCTION_DECL
970 && DECL_TEMPLATE_INFO (friend)
971 && !DECL_USE_TEMPLATE (friend))
973 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
974 friend = DECL_TI_TEMPLATE (friend);
975 need_template = false;
977 else if (TREE_CODE (friend) == TEMPLATE_DECL
978 && !PRIMARY_TEMPLATE_P (friend))
979 need_template = false;
981 /* There is nothing to do if this is not a template friend. */
982 if (TREE_CODE (friend) != TEMPLATE_DECL)
985 if (is_specialization_of (decl, friend))
989 A member of a class template may be declared to be a friend of a
990 non-template class. In this case, the corresponding member of
991 every specialization of the class template is a friend of the
992 class granting friendship.
994 For example, given a template friend declaration
996 template <class T> friend void A<T>::f();
998 the member function below is considered a friend
1000 template <> struct A<int> {
1004 For this type of template friend, TEMPLATE_DEPTH below will be
1005 nonzero. To determine if DECL is a friend of FRIEND, we first
1006 check if the enclosing class is a specialization of another. */
1008 template_depth = template_class_depth (DECL_CONTEXT (friend));
1010 && DECL_CLASS_SCOPE_P (decl)
1011 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1012 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1014 /* Next, we check the members themselves. In order to handle
1015 a few tricky cases, such as when FRIEND's are
1017 template <class T> friend void A<T>::g(T t);
1018 template <class T> template <T t> friend void A<T>::h();
1022 void A<int>::g(int);
1023 template <int> void A<int>::h();
1025 we need to figure out ARGS, the template arguments from
1026 the context of DECL. This is required for template substitution
1027 of `T' in the function parameter of `g' and template parameter
1028 of `h' in the above examples. Here ARGS corresponds to `int'. */
1030 tree context = DECL_CONTEXT (decl);
1031 tree args = NULL_TREE;
1032 int current_depth = 0;
1034 while (current_depth < template_depth)
1036 if (CLASSTYPE_TEMPLATE_INFO (context))
1038 if (current_depth == 0)
1039 args = TYPE_TI_ARGS (context);
1041 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1044 context = TYPE_CONTEXT (context);
1047 if (TREE_CODE (decl) == FUNCTION_DECL)
1052 tree friend_args_type;
1053 tree decl_args_type;
1055 /* Make sure that both DECL and FRIEND are templates or
1057 is_template = DECL_TEMPLATE_INFO (decl)
1058 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1059 if (need_template ^ is_template)
1061 else if (is_template)
1063 /* If both are templates, check template parameter list. */
1065 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1067 if (!comp_template_parms
1068 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1072 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1075 decl_type = TREE_TYPE (decl);
1077 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1078 tf_none, NULL_TREE);
1079 if (friend_type == error_mark_node)
1082 /* Check if return types match. */
1083 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1086 /* Check if function parameter types match, ignoring the
1087 `this' parameter. */
1088 friend_args_type = TYPE_ARG_TYPES (friend_type);
1089 decl_args_type = TYPE_ARG_TYPES (decl_type);
1090 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1091 friend_args_type = TREE_CHAIN (friend_args_type);
1092 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1093 decl_args_type = TREE_CHAIN (decl_args_type);
1095 return compparms (decl_args_type, friend_args_type);
1099 /* DECL is a TYPE_DECL */
1101 tree decl_type = TREE_TYPE (decl);
1103 /* Make sure that both DECL and FRIEND are templates or
1106 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1107 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1109 if (need_template ^ is_template)
1111 else if (is_template)
1114 /* If both are templates, check the name of the two
1115 TEMPLATE_DECL's first because is_friend didn't. */
1116 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1117 != DECL_NAME (friend))
1120 /* Now check template parameter list. */
1122 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1124 return comp_template_parms
1125 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1129 return (DECL_NAME (decl)
1130 == DECL_NAME (friend));
1136 /* Register the specialization SPEC as a specialization of TMPL with
1137 the indicated ARGS. IS_FRIEND indicates whether the specialization
1138 is actually just a friend declaration. Returns SPEC, or an
1139 equivalent prior declaration, if available. */
1142 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1146 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1148 if (TREE_CODE (spec) == FUNCTION_DECL
1149 && uses_template_parms (DECL_TI_ARGS (spec)))
1150 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1151 register it; we want the corresponding TEMPLATE_DECL instead.
1152 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1153 the more obvious `uses_template_parms (spec)' to avoid problems
1154 with default function arguments. In particular, given
1155 something like this:
1157 template <class T> void f(T t1, T t = T())
1159 the default argument expression is not substituted for in an
1160 instantiation unless and until it is actually needed. */
1163 fn = retrieve_specialization (tmpl, args,
1164 /*class_specializations_p=*/false);
1165 /* We can sometimes try to re-register a specialization that we've
1166 already got. In particular, regenerate_decl_from_template calls
1167 duplicate_decls which will update the specialization list. But,
1168 we'll still get called again here anyhow. It's more convenient
1169 to simply allow this than to try to prevent it. */
1172 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1174 if (DECL_TEMPLATE_INSTANTIATION (fn))
1177 || DECL_EXPLICIT_INSTANTIATION (fn))
1179 error ("specialization of %qD after instantiation",
1186 /* This situation should occur only if the first
1187 specialization is an implicit instantiation, the
1188 second is an explicit specialization, and the
1189 implicit instantiation has not yet been used. That
1190 situation can occur if we have implicitly
1191 instantiated a member function and then specialized
1194 We can also wind up here if a friend declaration that
1195 looked like an instantiation turns out to be a
1198 template <class T> void foo(T);
1199 class S { friend void foo<>(int) };
1200 template <> void foo(int);
1202 We transform the existing DECL in place so that any
1203 pointers to it become pointers to the updated
1206 If there was a definition for the template, but not
1207 for the specialization, we want this to look as if
1208 there were no definition, and vice versa. */
1209 DECL_INITIAL (fn) = NULL_TREE;
1210 duplicate_decls (spec, fn, is_friend);
1211 /* The call to duplicate_decls will have applied
1214 An explicit specialization of a function template
1215 is inline only if it is explicitly declared to be,
1216 and independently of whether its function tempalte
1219 to the primary function; now copy the inline bits to
1220 the various clones. */
1221 FOR_EACH_CLONE (clone, fn)
1223 DECL_DECLARED_INLINE_P (clone)
1224 = DECL_DECLARED_INLINE_P (fn);
1228 check_specialization_namespace (fn);
1233 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1235 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1236 /* Dup decl failed, but this is a new definition. Set the
1237 line number so any errors match this new
1239 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1245 /* A specialization must be declared in the same namespace as the
1246 template it is specializing. */
1247 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1248 && !check_specialization_namespace (tmpl))
1249 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1251 if (!optimize_specialization_lookup_p (tmpl))
1252 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1253 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1258 /* Unregister the specialization SPEC as a specialization of TMPL.
1259 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1260 if the SPEC was listed as a specialization of TMPL. */
1263 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1267 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1269 s = &TREE_CHAIN (*s))
1270 if (TREE_VALUE (*s) == spec)
1273 *s = TREE_CHAIN (*s);
1275 TREE_VALUE (*s) = new_spec;
1282 /* Compare an entry in the local specializations hash table P1 (which
1283 is really a pointer to a TREE_LIST) with P2 (which is really a
1287 eq_local_specializations (const void *p1, const void *p2)
1289 return TREE_VALUE ((tree) p1) == (tree) p2;
1292 /* Hash P1, an entry in the local specializations table. */
1295 hash_local_specialization (const void* p1)
1297 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1300 /* Like register_specialization, but for local declarations. We are
1301 registering SPEC, an instantiation of TMPL. */
1304 register_local_specialization (tree spec, tree tmpl)
1308 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1309 htab_hash_pointer (tmpl), INSERT);
1310 *slot = build_tree_list (spec, tmpl);
1313 /* Print the list of candidate FNS in an error message. */
1316 print_candidates (tree fns)
1320 const char *str = "candidates are:";
1322 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1326 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1327 error ("%s %+#D", str, OVL_CURRENT (f));
1332 /* Returns the template (one of the functions given by TEMPLATE_ID)
1333 which can be specialized to match the indicated DECL with the
1334 explicit template args given in TEMPLATE_ID. The DECL may be
1335 NULL_TREE if none is available. In that case, the functions in
1336 TEMPLATE_ID are non-members.
1338 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1339 specialization of a member template.
1341 The TEMPLATE_COUNT is the number of references to qualifying
1342 template classes that appeared in the name of the function. See
1343 check_explicit_specialization for a more accurate description.
1345 The template args (those explicitly specified and those deduced)
1346 are output in a newly created vector *TARGS_OUT.
1348 If it is impossible to determine the result, an error message is
1349 issued. The error_mark_node is returned to indicate failure. */
1352 determine_specialization (tree template_id,
1355 int need_member_template,
1360 tree explicit_targs;
1361 tree candidates = NULL_TREE;
1362 tree templates = NULL_TREE;
1364 struct cp_binding_level *b;
1366 *targs_out = NULL_TREE;
1368 if (template_id == error_mark_node)
1369 return error_mark_node;
1371 fns = TREE_OPERAND (template_id, 0);
1372 explicit_targs = TREE_OPERAND (template_id, 1);
1374 if (fns == error_mark_node)
1375 return error_mark_node;
1377 /* Check for baselinks. */
1378 if (BASELINK_P (fns))
1379 fns = BASELINK_FUNCTIONS (fns);
1381 if (!is_overloaded_fn (fns))
1383 error ("%qD is not a function template", fns);
1384 return error_mark_node;
1387 /* Count the number of template headers specified for this
1390 for (b = current_binding_level;
1391 b->kind == sk_template_parms;
1395 for (; fns; fns = OVL_NEXT (fns))
1397 tree fn = OVL_CURRENT (fns);
1399 if (TREE_CODE (fn) == TEMPLATE_DECL)
1401 tree decl_arg_types;
1404 /* DECL might be a specialization of FN. */
1406 /* Adjust the type of DECL in case FN is a static member. */
1407 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1408 if (DECL_STATIC_FUNCTION_P (fn)
1409 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1410 decl_arg_types = TREE_CHAIN (decl_arg_types);
1412 /* Check that the number of function parameters matches.
1414 template <class T> void f(int i = 0);
1415 template <> void f<int>();
1416 The specialization f<int> is invalid but is not caught
1417 by get_bindings below. */
1419 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1420 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1423 /* For a non-static member function, we need to make sure that
1424 the const qualification is the same. This can be done by
1425 checking the 'this' in the argument list. */
1426 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1427 && !same_type_p (TREE_VALUE (fn_arg_types),
1428 TREE_VALUE (decl_arg_types)))
1431 /* In case of explicit specialization, we need to check if
1432 the number of template headers appearing in the specialization
1433 is correct. This is usually done in check_explicit_specialization,
1434 but the check done there cannot be exhaustive when specializing
1435 member functions. Consider the following code:
1437 template <> void A<int>::f(int);
1438 template <> template <> void A<int>::f(int);
1440 Assuming that A<int> is not itself an explicit specialization
1441 already, the first line specializes "f" which is a non-template
1442 member function, whilst the second line specializes "f" which
1443 is a template member function. So both lines are syntactically
1444 correct, and check_explicit_specialization does not reject
1447 Here, we can do better, as we are matching the specialization
1448 against the declarations. We count the number of template
1449 headers, and we check if they match TEMPLATE_COUNT + 1
1450 (TEMPLATE_COUNT is the number of qualifying template classes,
1451 plus there must be another header for the member template
1454 Notice that if header_count is zero, this is not a
1455 specialization but rather a template instantiation, so there
1456 is no check we can perform here. */
1457 if (header_count && header_count != template_count + 1)
1460 /* Check that the number of template arguments at the
1461 innermost level for DECL is the same as for FN. */
1462 if (current_binding_level->kind == sk_template_parms
1463 && !current_binding_level->explicit_spec_p
1464 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1465 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1466 (current_template_parms))))
1469 /* See whether this function might be a specialization of this
1471 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1474 /* We cannot deduce template arguments that when used to
1475 specialize TMPL will produce DECL. */
1478 /* Save this template, and the arguments deduced. */
1479 templates = tree_cons (targs, fn, templates);
1481 else if (need_member_template)
1482 /* FN is an ordinary member function, and we need a
1483 specialization of a member template. */
1485 else if (TREE_CODE (fn) != FUNCTION_DECL)
1486 /* We can get IDENTIFIER_NODEs here in certain erroneous
1489 else if (!DECL_FUNCTION_MEMBER_P (fn))
1490 /* This is just an ordinary non-member function. Nothing can
1491 be a specialization of that. */
1493 else if (DECL_ARTIFICIAL (fn))
1494 /* Cannot specialize functions that are created implicitly. */
1498 tree decl_arg_types;
1500 /* This is an ordinary member function. However, since
1501 we're here, we can assume it's enclosing class is a
1502 template class. For example,
1504 template <typename T> struct S { void f(); };
1505 template <> void S<int>::f() {}
1507 Here, S<int>::f is a non-template, but S<int> is a
1508 template class. If FN has the same type as DECL, we
1509 might be in business. */
1511 if (!DECL_TEMPLATE_INFO (fn))
1512 /* Its enclosing class is an explicit specialization
1513 of a template class. This is not a candidate. */
1516 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1517 TREE_TYPE (TREE_TYPE (fn))))
1518 /* The return types differ. */
1521 /* Adjust the type of DECL in case FN is a static member. */
1522 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1523 if (DECL_STATIC_FUNCTION_P (fn)
1524 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1525 decl_arg_types = TREE_CHAIN (decl_arg_types);
1527 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1530 candidates = tree_cons (NULL_TREE, fn, candidates);
1534 if (templates && TREE_CHAIN (templates))
1540 It is possible for a specialization with a given function
1541 signature to be instantiated from more than one function
1542 template. In such cases, explicit specification of the
1543 template arguments must be used to uniquely identify the
1544 function template specialization being specialized.
1546 Note that here, there's no suggestion that we're supposed to
1547 determine which of the candidate templates is most
1548 specialized. However, we, also have:
1552 Partial ordering of overloaded function template
1553 declarations is used in the following contexts to select
1554 the function template to which a function template
1555 specialization refers:
1557 -- when an explicit specialization refers to a function
1560 So, we do use the partial ordering rules, at least for now.
1561 This extension can only serve to make invalid programs valid,
1562 so it's safe. And, there is strong anecdotal evidence that
1563 the committee intended the partial ordering rules to apply;
1564 the EDG front-end has that behavior, and John Spicer claims
1565 that the committee simply forgot to delete the wording in
1566 [temp.expl.spec]. */
1567 tree tmpl = most_specialized (templates, decl, explicit_targs);
1568 if (tmpl && tmpl != error_mark_node)
1570 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1571 templates = tree_cons (targs, tmpl, NULL_TREE);
1575 if (templates == NULL_TREE && candidates == NULL_TREE)
1577 error ("template-id %qD for %q+D does not match any template "
1578 "declaration", template_id, decl);
1579 return error_mark_node;
1581 else if ((templates && TREE_CHAIN (templates))
1582 || (candidates && TREE_CHAIN (candidates))
1583 || (templates && candidates))
1585 error ("ambiguous template specialization %qD for %q+D",
1587 chainon (candidates, templates);
1588 print_candidates (candidates);
1589 return error_mark_node;
1592 /* We have one, and exactly one, match. */
1595 /* It was a specialization of an ordinary member function in a
1597 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1598 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1601 /* It was a specialization of a template. */
1602 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1603 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1605 *targs_out = copy_node (targs);
1606 SET_TMPL_ARGS_LEVEL (*targs_out,
1607 TMPL_ARGS_DEPTH (*targs_out),
1608 TREE_PURPOSE (templates));
1611 *targs_out = TREE_PURPOSE (templates);
1612 return TREE_VALUE (templates);
1615 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1616 but with the default argument values filled in from those in the
1620 copy_default_args_to_explicit_spec_1 (tree spec_types,
1623 tree new_spec_types;
1628 if (spec_types == void_list_node)
1629 return void_list_node;
1631 /* Substitute into the rest of the list. */
1633 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1634 TREE_CHAIN (tmpl_types));
1636 /* Add the default argument for this parameter. */
1637 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1638 TREE_VALUE (spec_types),
1642 /* DECL is an explicit specialization. Replicate default arguments
1643 from the template it specializes. (That way, code like:
1645 template <class T> void f(T = 3);
1646 template <> void f(double);
1649 works, as required.) An alternative approach would be to look up
1650 the correct default arguments at the call-site, but this approach
1651 is consistent with how implicit instantiations are handled. */
1654 copy_default_args_to_explicit_spec (tree decl)
1659 tree new_spec_types;
1663 tree object_type = NULL_TREE;
1664 tree in_charge = NULL_TREE;
1665 tree vtt = NULL_TREE;
1667 /* See if there's anything we need to do. */
1668 tmpl = DECL_TI_TEMPLATE (decl);
1669 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1670 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1671 if (TREE_PURPOSE (t))
1676 old_type = TREE_TYPE (decl);
1677 spec_types = TYPE_ARG_TYPES (old_type);
1679 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1681 /* Remove the this pointer, but remember the object's type for
1683 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1684 spec_types = TREE_CHAIN (spec_types);
1685 tmpl_types = TREE_CHAIN (tmpl_types);
1687 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1689 /* DECL may contain more parameters than TMPL due to the extra
1690 in-charge parameter in constructors and destructors. */
1691 in_charge = spec_types;
1692 spec_types = TREE_CHAIN (spec_types);
1694 if (DECL_HAS_VTT_PARM_P (decl))
1697 spec_types = TREE_CHAIN (spec_types);
1701 /* Compute the merged default arguments. */
1703 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1705 /* Compute the new FUNCTION_TYPE. */
1709 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1714 /* Put the in-charge parameter back. */
1715 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1716 TREE_VALUE (in_charge),
1719 new_type = build_method_type_directly (object_type,
1720 TREE_TYPE (old_type),
1724 new_type = build_function_type (TREE_TYPE (old_type),
1726 new_type = cp_build_type_attribute_variant (new_type,
1727 TYPE_ATTRIBUTES (old_type));
1728 new_type = build_exception_variant (new_type,
1729 TYPE_RAISES_EXCEPTIONS (old_type));
1730 TREE_TYPE (decl) = new_type;
1733 /* Check to see if the function just declared, as indicated in
1734 DECLARATOR, and in DECL, is a specialization of a function
1735 template. We may also discover that the declaration is an explicit
1736 instantiation at this point.
1738 Returns DECL, or an equivalent declaration that should be used
1739 instead if all goes well. Issues an error message if something is
1740 amiss. Returns error_mark_node if the error is not easily
1743 FLAGS is a bitmask consisting of the following flags:
1745 2: The function has a definition.
1746 4: The function is a friend.
1748 The TEMPLATE_COUNT is the number of references to qualifying
1749 template classes that appeared in the name of the function. For
1752 template <class T> struct S { void f(); };
1755 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1756 classes are not counted in the TEMPLATE_COUNT, so that in
1758 template <class T> struct S {};
1759 template <> struct S<int> { void f(); }
1760 template <> void S<int>::f();
1762 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1763 invalid; there should be no template <>.)
1765 If the function is a specialization, it is marked as such via
1766 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1767 is set up correctly, and it is added to the list of specializations
1768 for that template. */
1771 check_explicit_specialization (tree declarator,
1776 int have_def = flags & 2;
1777 int is_friend = flags & 4;
1778 int specialization = 0;
1779 int explicit_instantiation = 0;
1780 int member_specialization = 0;
1781 tree ctype = DECL_CLASS_CONTEXT (decl);
1782 tree dname = DECL_NAME (decl);
1787 if (!processing_specialization)
1790 tsk = tsk_excessive_parms;
1793 tsk = current_tmpl_spec_kind (template_count);
1798 if (processing_specialization)
1801 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1803 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1806 /* This could be something like:
1808 template <class T> void f(T);
1809 class S { friend void f<>(int); } */
1813 /* This case handles bogus declarations like template <>
1814 template <class T> void f<int>(); */
1816 error ("template-id %qD in declaration of primary template",
1823 case tsk_invalid_member_spec:
1824 /* The error has already been reported in
1825 check_specialization_scope. */
1826 return error_mark_node;
1828 case tsk_invalid_expl_inst:
1829 error ("template parameter list used in explicit instantiation");
1835 error ("definition provided for explicit instantiation");
1837 explicit_instantiation = 1;
1840 case tsk_excessive_parms:
1841 case tsk_insufficient_parms:
1842 if (tsk == tsk_excessive_parms)
1843 error ("too many template parameter lists in declaration of %qD",
1845 else if (template_header_count)
1846 error("too few template parameter lists in declaration of %qD", decl);
1848 error("explicit specialization of %qD must be introduced by "
1849 "%<template <>%>", decl);
1853 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1855 member_specialization = 1;
1861 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1863 /* This case handles bogus declarations like template <>
1864 template <class T> void f<int>(); */
1866 if (uses_template_parms (declarator))
1867 error ("function template partial specialization %qD "
1868 "is not allowed", declarator);
1870 error ("template-id %qD in declaration of primary template",
1875 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1876 /* This is a specialization of a member template, without
1877 specialization the containing class. Something like:
1879 template <class T> struct S {
1880 template <class U> void f (U);
1882 template <> template <class U> void S<int>::f(U) {}
1884 That's a specialization -- but of the entire template. */
1892 if (specialization || member_specialization)
1894 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1895 for (; t; t = TREE_CHAIN (t))
1896 if (TREE_PURPOSE (t))
1899 ("default argument specified in explicit specialization");
1904 if (specialization || member_specialization || explicit_instantiation)
1906 tree tmpl = NULL_TREE;
1907 tree targs = NULL_TREE;
1909 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1910 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1914 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1919 /* If there is no class context, the explicit instantiation
1920 must be at namespace scope. */
1921 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1923 /* Find the namespace binding, using the declaration
1925 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1926 if (!fns || !is_overloaded_fn (fns))
1928 error ("%qD is not a template function", dname);
1929 fns = error_mark_node;
1933 declarator = lookup_template_function (fns, NULL_TREE);
1936 if (declarator == error_mark_node)
1937 return error_mark_node;
1939 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1941 if (!explicit_instantiation)
1942 /* A specialization in class scope. This is invalid,
1943 but the error will already have been flagged by
1944 check_specialization_scope. */
1945 return error_mark_node;
1948 /* It's not valid to write an explicit instantiation in
1951 class C { template void f(); }
1953 This case is caught by the parser. However, on
1956 template class C { void f(); };
1958 (which is invalid) we can get here. The error will be
1965 else if (ctype != NULL_TREE
1966 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1969 /* Find the list of functions in ctype that have the same
1970 name as the declared function. */
1971 tree name = TREE_OPERAND (declarator, 0);
1972 tree fns = NULL_TREE;
1975 if (constructor_name_p (name, ctype))
1977 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1979 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1980 : !CLASSTYPE_DESTRUCTORS (ctype))
1982 /* From [temp.expl.spec]:
1984 If such an explicit specialization for the member
1985 of a class template names an implicitly-declared
1986 special member function (clause _special_), the
1987 program is ill-formed.
1989 Similar language is found in [temp.explicit]. */
1990 error ("specialization of implicitly-declared special member function");
1991 return error_mark_node;
1994 name = is_constructor ? ctor_identifier : dtor_identifier;
1997 if (!DECL_CONV_FN_P (decl))
1999 idx = lookup_fnfields_1 (ctype, name);
2001 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2005 VEC(tree,gc) *methods;
2008 /* For a type-conversion operator, we cannot do a
2009 name-based lookup. We might be looking for `operator
2010 int' which will be a specialization of `operator T'.
2011 So, we find *all* the conversion operators, and then
2012 select from them. */
2015 methods = CLASSTYPE_METHOD_VEC (ctype);
2017 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2018 VEC_iterate (tree, methods, idx, ovl);
2021 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2022 /* There are no more conversion functions. */
2025 /* Glue all these conversion functions together
2026 with those we already have. */
2027 for (; ovl; ovl = OVL_NEXT (ovl))
2028 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2032 if (fns == NULL_TREE)
2034 error ("no member function %qD declared in %qT", name, ctype);
2035 return error_mark_node;
2038 TREE_OPERAND (declarator, 0) = fns;
2041 /* Figure out what exactly is being specialized at this point.
2042 Note that for an explicit instantiation, even one for a
2043 member function, we cannot tell apriori whether the
2044 instantiation is for a member template, or just a member
2045 function of a template class. Even if a member template is
2046 being instantiated, the member template arguments may be
2047 elided if they can be deduced from the rest of the
2049 tmpl = determine_specialization (declarator, decl,
2051 member_specialization,
2054 if (!tmpl || tmpl == error_mark_node)
2055 /* We couldn't figure out what this declaration was
2057 return error_mark_node;
2060 tree gen_tmpl = most_general_template (tmpl);
2062 if (explicit_instantiation)
2064 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2065 is done by do_decl_instantiation later. */
2067 int arg_depth = TMPL_ARGS_DEPTH (targs);
2068 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2070 if (arg_depth > parm_depth)
2072 /* If TMPL is not the most general template (for
2073 example, if TMPL is a friend template that is
2074 injected into namespace scope), then there will
2075 be too many levels of TARGS. Remove some of them
2080 new_targs = make_tree_vec (parm_depth);
2081 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2082 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2083 = TREE_VEC_ELT (targs, i);
2087 return instantiate_template (tmpl, targs, tf_error);
2090 /* If we thought that the DECL was a member function, but it
2091 turns out to be specializing a static member function,
2092 make DECL a static member function as well. */
2093 if (DECL_STATIC_FUNCTION_P (tmpl)
2094 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2095 revert_static_member_fn (decl);
2097 /* If this is a specialization of a member template of a
2098 template class. In we want to return the TEMPLATE_DECL,
2099 not the specialization of it. */
2100 if (tsk == tsk_template)
2102 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2103 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2106 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2107 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2108 = DECL_SOURCE_LOCATION (decl);
2109 /* We want to use the argument list specified in the
2110 definition, not in the original declaration. */
2111 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2112 = DECL_ARGUMENTS (decl);
2117 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2118 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2120 /* Inherit default function arguments from the template
2121 DECL is specializing. */
2122 copy_default_args_to_explicit_spec (decl);
2124 /* This specialization has the same protection as the
2125 template it specializes. */
2126 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2127 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2128 /* The specialization has the same visibility as the
2129 template it specializes. */
2130 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2132 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2133 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2135 /* If DECL is a friend declaration, declared using an
2136 unqualified name, the namespace associated with DECL may
2137 have been set incorrectly. For example, in:
2139 template <typename T> void f(T);
2141 struct S { friend void f<int>(int); }
2144 we will have set the DECL_CONTEXT for the friend
2145 declaration to N, rather than to the global namespace. */
2146 if (DECL_NAMESPACE_SCOPE_P (decl))
2147 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2149 if (is_friend && !have_def)
2150 /* This is not really a declaration of a specialization.
2151 It's just the name of an instantiation. But, it's not
2152 a request for an instantiation, either. */
2153 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2154 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2155 /* This is indeed a specialization. In case of constructors
2156 and destructors, we need in-charge and not-in-charge
2157 versions in V3 ABI. */
2158 clone_function_decl (decl, /*update_method_vec_p=*/0);
2160 /* Register this specialization so that we can find it
2162 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2169 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2170 parameters. These are represented in the same format used for
2171 DECL_TEMPLATE_PARMS. */
2174 comp_template_parms (tree parms1, tree parms2)
2179 if (parms1 == parms2)
2182 for (p1 = parms1, p2 = parms2;
2183 p1 != NULL_TREE && p2 != NULL_TREE;
2184 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2186 tree t1 = TREE_VALUE (p1);
2187 tree t2 = TREE_VALUE (p2);
2190 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2191 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2193 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2196 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2198 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2199 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2201 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2204 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2206 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2211 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2212 /* One set of parameters has more parameters lists than the
2219 /* Complain if DECL shadows a template parameter.
2221 [temp.local]: A template-parameter shall not be redeclared within its
2222 scope (including nested scopes). */
2225 check_template_shadow (tree decl)
2229 /* If we're not in a template, we can't possibly shadow a template
2231 if (!current_template_parms)
2234 /* Figure out what we're shadowing. */
2235 if (TREE_CODE (decl) == OVERLOAD)
2236 decl = OVL_CURRENT (decl);
2237 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2239 /* If there's no previous binding for this name, we're not shadowing
2240 anything, let alone a template parameter. */
2244 /* If we're not shadowing a template parameter, we're done. Note
2245 that OLDDECL might be an OVERLOAD (or perhaps even an
2246 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2248 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2251 /* We check for decl != olddecl to avoid bogus errors for using a
2252 name inside a class. We check TPFI to avoid duplicate errors for
2253 inline member templates. */
2255 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2258 error ("declaration of %q+#D", decl);
2259 error (" shadows template parm %q+#D", olddecl);
2262 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2263 ORIG_LEVEL, DECL, and TYPE. */
2266 build_template_parm_index (int index,
2272 tree t = make_node (TEMPLATE_PARM_INDEX);
2273 TEMPLATE_PARM_IDX (t) = index;
2274 TEMPLATE_PARM_LEVEL (t) = level;
2275 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2276 TEMPLATE_PARM_DECL (t) = decl;
2277 TREE_TYPE (t) = type;
2278 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2279 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2280 TREE_READONLY (t) = TREE_READONLY (decl);
2285 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2286 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2287 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2288 new one is created. */
2291 reduce_template_parm_level (tree index, tree type, int levels)
2293 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2294 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2295 != TEMPLATE_PARM_LEVEL (index) - levels))
2297 tree orig_decl = TEMPLATE_PARM_DECL (index);
2300 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2301 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2302 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2303 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2304 DECL_ARTIFICIAL (decl) = 1;
2305 SET_DECL_TEMPLATE_PARM_P (decl);
2307 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2308 TEMPLATE_PARM_LEVEL (index) - levels,
2309 TEMPLATE_PARM_ORIG_LEVEL (index),
2311 TEMPLATE_PARM_DESCENDANTS (index) = t;
2313 /* Template template parameters need this. */
2314 if (TREE_CODE (decl) != CONST_DECL)
2315 DECL_TEMPLATE_PARMS (decl)
2316 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2319 return TEMPLATE_PARM_DESCENDANTS (index);
2322 /* Process information from new template parameter NEXT and append it to the
2323 LIST being built. This new parameter is a non-type parameter iff
2324 IS_NON_TYPE is true. */
2327 process_template_parm (tree list, tree next, bool is_non_type)
2335 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2336 defval = TREE_PURPOSE (parm);
2340 tree p = TREE_VALUE (tree_last (list));
2342 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2343 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2345 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2353 parm = TREE_VALUE (parm);
2355 SET_DECL_TEMPLATE_PARM_P (parm);
2359 The top-level cv-qualifiers on the template-parameter are
2360 ignored when determining its type. */
2361 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2363 /* A template parameter is not modifiable. */
2364 TREE_CONSTANT (parm) = 1;
2365 TREE_INVARIANT (parm) = 1;
2366 TREE_READONLY (parm) = 1;
2367 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2368 TREE_TYPE (parm) = void_type_node;
2369 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2370 TREE_CONSTANT (decl) = 1;
2371 TREE_INVARIANT (decl) = 1;
2372 TREE_READONLY (decl) = 1;
2373 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2374 = build_template_parm_index (idx, processing_template_decl,
2375 processing_template_decl,
2376 decl, TREE_TYPE (parm));
2381 parm = TREE_VALUE (TREE_VALUE (parm));
2383 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2385 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2386 /* This is for distinguishing between real templates and template
2387 template parameters */
2388 TREE_TYPE (parm) = t;
2389 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2394 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2395 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2396 decl = build_decl (TYPE_DECL, parm, t);
2399 TYPE_NAME (t) = decl;
2400 TYPE_STUB_DECL (t) = decl;
2402 TEMPLATE_TYPE_PARM_INDEX (t)
2403 = build_template_parm_index (idx, processing_template_decl,
2404 processing_template_decl,
2405 decl, TREE_TYPE (parm));
2407 DECL_ARTIFICIAL (decl) = 1;
2408 SET_DECL_TEMPLATE_PARM_P (decl);
2410 parm = build_tree_list (defval, parm);
2411 return chainon (list, parm);
2414 /* The end of a template parameter list has been reached. Process the
2415 tree list into a parameter vector, converting each parameter into a more
2416 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2420 end_template_parm_list (tree parms)
2424 tree saved_parmlist = make_tree_vec (list_length (parms));
2426 current_template_parms
2427 = tree_cons (size_int (processing_template_decl),
2428 saved_parmlist, current_template_parms);
2430 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2432 next = TREE_CHAIN (parm);
2433 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2434 TREE_CHAIN (parm) = NULL_TREE;
2437 --processing_template_parmlist;
2439 return saved_parmlist;
2442 /* end_template_decl is called after a template declaration is seen. */
2445 end_template_decl (void)
2447 reset_specialization ();
2449 if (! processing_template_decl)
2452 /* This matches the pushlevel in begin_template_parm_list. */
2455 --processing_template_decl;
2456 current_template_parms = TREE_CHAIN (current_template_parms);
2459 /* Given a template argument vector containing the template PARMS.
2460 The innermost PARMS are given first. */
2463 current_template_args (void)
2466 tree args = NULL_TREE;
2467 int length = TMPL_PARMS_DEPTH (current_template_parms);
2470 /* If there is only one level of template parameters, we do not
2471 create a TREE_VEC of TREE_VECs. Instead, we return a single
2472 TREE_VEC containing the arguments. */
2474 args = make_tree_vec (length);
2476 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2478 tree a = copy_node (TREE_VALUE (header));
2481 TREE_TYPE (a) = NULL_TREE;
2482 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2484 tree t = TREE_VEC_ELT (a, i);
2486 /* T will be a list if we are called from within a
2487 begin/end_template_parm_list pair, but a vector directly
2488 if within a begin/end_member_template_processing pair. */
2489 if (TREE_CODE (t) == TREE_LIST)
2493 if (TREE_CODE (t) == TYPE_DECL
2494 || TREE_CODE (t) == TEMPLATE_DECL)
2497 t = DECL_INITIAL (t);
2498 TREE_VEC_ELT (a, i) = t;
2503 TREE_VEC_ELT (args, --l) = a;
2511 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2512 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2513 a member template. Used by push_template_decl below. */
2516 build_template_decl (tree decl, tree parms, bool member_template_p)
2518 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2519 DECL_TEMPLATE_PARMS (tmpl) = parms;
2520 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2521 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2522 if (DECL_LANG_SPECIFIC (decl))
2524 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2525 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2526 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2527 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2528 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2529 if (DECL_OVERLOADED_OPERATOR_P (decl))
2530 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2531 DECL_OVERLOADED_OPERATOR_P (decl));
2537 struct template_parm_data
2539 /* The level of the template parameters we are currently
2543 /* The index of the specialization argument we are currently
2547 /* An array whose size is the number of template parameters. The
2548 elements are nonzero if the parameter has been used in any one
2549 of the arguments processed so far. */
2552 /* An array whose size is the number of template arguments. The
2553 elements are nonzero if the argument makes use of template
2554 parameters of this level. */
2555 int* arg_uses_template_parms;
2558 /* Subroutine of push_template_decl used to see if each template
2559 parameter in a partial specialization is used in the explicit
2560 argument list. If T is of the LEVEL given in DATA (which is
2561 treated as a template_parm_data*), then DATA->PARMS is marked
2565 mark_template_parm (tree t, void* data)
2569 struct template_parm_data* tpd = (struct template_parm_data*) data;
2571 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2573 level = TEMPLATE_PARM_LEVEL (t);
2574 idx = TEMPLATE_PARM_IDX (t);
2578 level = TEMPLATE_TYPE_LEVEL (t);
2579 idx = TEMPLATE_TYPE_IDX (t);
2582 if (level == tpd->level)
2584 tpd->parms[idx] = 1;
2585 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2588 /* Return zero so that for_each_template_parm will continue the
2589 traversal of the tree; we want to mark *every* template parm. */
2593 /* Process the partial specialization DECL. */
2596 process_partial_specialization (tree decl)
2598 tree type = TREE_TYPE (decl);
2599 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2600 tree specargs = CLASSTYPE_TI_ARGS (type);
2601 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2602 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2603 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2604 int nargs = TREE_VEC_LENGTH (inner_args);
2605 int ntparms = TREE_VEC_LENGTH (inner_parms);
2607 int did_error_intro = 0;
2608 struct template_parm_data tpd;
2609 struct template_parm_data tpd2;
2611 /* We check that each of the template parameters given in the
2612 partial specialization is used in the argument list to the
2613 specialization. For example:
2615 template <class T> struct S;
2616 template <class T> struct S<T*>;
2618 The second declaration is OK because `T*' uses the template
2619 parameter T, whereas
2621 template <class T> struct S<int>;
2623 is no good. Even trickier is:
2634 The S2<T> declaration is actually invalid; it is a
2635 full-specialization. Of course,
2638 struct S2<T (*)(U)>;
2640 or some such would have been OK. */
2641 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2642 tpd.parms = alloca (sizeof (int) * ntparms);
2643 memset (tpd.parms, 0, sizeof (int) * ntparms);
2645 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2646 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2647 for (i = 0; i < nargs; ++i)
2649 tpd.current_arg = i;
2650 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2651 &mark_template_parm,
2655 for (i = 0; i < ntparms; ++i)
2656 if (tpd.parms[i] == 0)
2658 /* One of the template parms was not used in the
2660 if (!did_error_intro)
2662 error ("template parameters not used in partial specialization:");
2663 did_error_intro = 1;
2666 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2669 /* [temp.class.spec]
2671 The argument list of the specialization shall not be identical to
2672 the implicit argument list of the primary template. */
2673 if (comp_template_args
2675 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2677 error ("partial specialization %qT does not specialize any template arguments", type);
2679 /* [temp.class.spec]
2681 A partially specialized non-type argument expression shall not
2682 involve template parameters of the partial specialization except
2683 when the argument expression is a simple identifier.
2685 The type of a template parameter corresponding to a specialized
2686 non-type argument shall not be dependent on a parameter of the
2688 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2690 for (i = 0; i < nargs; ++i)
2692 tree arg = TREE_VEC_ELT (inner_args, i);
2693 if (/* These first two lines are the `non-type' bit. */
2695 && TREE_CODE (arg) != TEMPLATE_DECL
2696 /* This next line is the `argument expression is not just a
2697 simple identifier' condition and also the `specialized
2698 non-type argument' bit. */
2699 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2701 if (tpd.arg_uses_template_parms[i])
2702 error ("template argument %qE involves template parameter(s)", arg);
2705 /* Look at the corresponding template parameter,
2706 marking which template parameters its type depends
2709 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2714 /* We haven't yet initialized TPD2. Do so now. */
2715 tpd2.arg_uses_template_parms
2716 = alloca (sizeof (int) * nargs);
2717 /* The number of parameters here is the number in the
2718 main template, which, as checked in the assertion
2720 tpd2.parms = alloca (sizeof (int) * nargs);
2722 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2725 /* Mark the template parameters. But this time, we're
2726 looking for the template parameters of the main
2727 template, not in the specialization. */
2728 tpd2.current_arg = i;
2729 tpd2.arg_uses_template_parms[i] = 0;
2730 memset (tpd2.parms, 0, sizeof (int) * nargs);
2731 for_each_template_parm (type,
2732 &mark_template_parm,
2736 if (tpd2.arg_uses_template_parms [i])
2738 /* The type depended on some template parameters.
2739 If they are fully specialized in the
2740 specialization, that's OK. */
2742 for (j = 0; j < nargs; ++j)
2743 if (tpd2.parms[j] != 0
2744 && tpd.arg_uses_template_parms [j])
2746 error ("type %qT of template argument %qE depends "
2747 "on template parameter(s)",
2757 if (retrieve_specialization (maintmpl, specargs,
2758 /*class_specializations_p=*/true))
2759 /* We've already got this specialization. */
2762 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2763 = tree_cons (specargs, inner_parms,
2764 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2765 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2769 /* Check that a template declaration's use of default arguments is not
2770 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2771 nonzero if DECL is the thing declared by a primary template.
2772 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2775 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2778 int last_level_to_check;
2783 A default template-argument shall not be specified in a
2784 function template declaration or a function template definition, nor
2785 in the template-parameter-list of the definition of a member of a
2788 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2789 /* You can't have a function template declaration in a local
2790 scope, nor you can you define a member of a class template in a
2794 if (current_class_type
2795 && !TYPE_BEING_DEFINED (current_class_type)
2796 && DECL_LANG_SPECIFIC (decl)
2797 /* If this is either a friend defined in the scope of the class
2798 or a member function. */
2799 && (DECL_FUNCTION_MEMBER_P (decl)
2800 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2801 : DECL_FRIEND_CONTEXT (decl)
2802 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2804 /* And, if it was a member function, it really was defined in
2805 the scope of the class. */
2806 && (!DECL_FUNCTION_MEMBER_P (decl)
2807 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2808 /* We already checked these parameters when the template was
2809 declared, so there's no need to do it again now. This function
2810 was defined in class scope, but we're processing it's body now
2811 that the class is complete. */
2816 If a template-parameter has a default template-argument, all
2817 subsequent template-parameters shall have a default
2818 template-argument supplied. */
2819 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2821 tree inner_parms = TREE_VALUE (parm_level);
2822 int ntparms = TREE_VEC_LENGTH (inner_parms);
2823 int seen_def_arg_p = 0;
2826 for (i = 0; i < ntparms; ++i)
2828 tree parm = TREE_VEC_ELT (inner_parms, i);
2829 if (TREE_PURPOSE (parm))
2831 else if (seen_def_arg_p)
2833 error ("no default argument for %qD", TREE_VALUE (parm));
2834 /* For better subsequent error-recovery, we indicate that
2835 there should have been a default argument. */
2836 TREE_PURPOSE (parm) = error_mark_node;
2841 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2842 /* For an ordinary class template, default template arguments are
2843 allowed at the innermost level, e.g.:
2844 template <class T = int>
2846 but, in a partial specialization, they're not allowed even
2847 there, as we have in [temp.class.spec]:
2849 The template parameter list of a specialization shall not
2850 contain default template argument values.
2852 So, for a partial specialization, or for a function template,
2853 we look at all of them. */
2856 /* But, for a primary class template that is not a partial
2857 specialization we look at all template parameters except the
2859 parms = TREE_CHAIN (parms);
2861 /* Figure out what error message to issue. */
2862 if (TREE_CODE (decl) == FUNCTION_DECL)
2863 msg = "default template arguments may not be used in function templates";
2864 else if (is_partial)
2865 msg = "default template arguments may not be used in partial specializations";
2867 msg = "default argument for template parameter for class enclosing %qD";
2869 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2870 /* If we're inside a class definition, there's no need to
2871 examine the parameters to the class itself. On the one
2872 hand, they will be checked when the class is defined, and,
2873 on the other, default arguments are valid in things like:
2874 template <class T = double>
2875 struct S { template <class U> void f(U); };
2876 Here the default argument for `S' has no bearing on the
2877 declaration of `f'. */
2878 last_level_to_check = template_class_depth (current_class_type) + 1;
2880 /* Check everything. */
2881 last_level_to_check = 0;
2883 for (parm_level = parms;
2884 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2885 parm_level = TREE_CHAIN (parm_level))
2887 tree inner_parms = TREE_VALUE (parm_level);
2891 ntparms = TREE_VEC_LENGTH (inner_parms);
2892 for (i = 0; i < ntparms; ++i)
2893 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2901 /* Clear out the default argument so that we are not
2903 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2906 /* At this point, if we're still interested in issuing messages,
2907 they must apply to classes surrounding the object declared. */
2909 msg = "default argument for template parameter for class enclosing %qD";
2913 /* Worker for push_template_decl_real, called via
2914 for_each_template_parm. DATA is really an int, indicating the
2915 level of the parameters we are interested in. If T is a template
2916 parameter of that level, return nonzero. */
2919 template_parm_this_level_p (tree t, void* data)
2921 int this_level = *(int *)data;
2924 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2925 level = TEMPLATE_PARM_LEVEL (t);
2927 level = TEMPLATE_TYPE_LEVEL (t);
2928 return level == this_level;
2931 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2932 parameters given by current_template_args, or reuses a
2933 previously existing one, if appropriate. Returns the DECL, or an
2934 equivalent one, if it is replaced via a call to duplicate_decls.
2936 If IS_FRIEND is true, DECL is a friend declaration. */
2939 push_template_decl_real (tree decl, bool is_friend)
2947 int new_template_p = 0;
2948 /* True if the template is a member template, in the sense of
2950 bool member_template_p = false;
2952 if (decl == error_mark_node)
2955 /* See if this is a partial specialization. */
2956 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2957 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2958 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2960 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
2964 /* For a friend, we want the context of the friend function, not
2965 the type of which it is a friend. */
2966 ctx = DECL_CONTEXT (decl);
2967 else if (CP_DECL_CONTEXT (decl)
2968 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2969 /* In the case of a virtual function, we want the class in which
2971 ctx = CP_DECL_CONTEXT (decl);
2973 /* Otherwise, if we're currently defining some class, the DECL
2974 is assumed to be a member of the class. */
2975 ctx = current_scope ();
2977 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2980 if (!DECL_CONTEXT (decl))
2981 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2983 /* See if this is a primary template. */
2984 primary = template_parm_scope_p ();
2988 if (DECL_CLASS_SCOPE_P (decl))
2989 member_template_p = true;
2990 if (TREE_CODE (decl) == TYPE_DECL
2991 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2992 error ("template class without a name");
2993 else if (TREE_CODE (decl) == FUNCTION_DECL)
2995 if (DECL_DESTRUCTOR_P (decl))
2999 A destructor shall not be a member template. */
3000 error ("destructor %qD declared as member template", decl);
3001 return error_mark_node;
3003 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3004 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3005 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3006 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3007 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3008 == void_list_node)))
3010 /* [basic.stc.dynamic.allocation]
3012 An allocation function can be a function
3013 template. ... Template allocation functions shall
3014 have two or more parameters. */
3015 error ("invalid template declaration of %qD", decl);
3019 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3020 && CLASS_TYPE_P (TREE_TYPE (decl)))
3024 error ("template declaration of %q#D", decl);
3025 return error_mark_node;
3029 /* Check to see that the rules regarding the use of default
3030 arguments are not being violated. */
3031 check_default_tmpl_args (decl, current_template_parms,
3032 primary, is_partial);
3035 return process_partial_specialization (decl);
3037 args = current_template_args ();
3040 || TREE_CODE (ctx) == FUNCTION_DECL
3041 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3042 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3044 if (DECL_LANG_SPECIFIC (decl)
3045 && DECL_TEMPLATE_INFO (decl)
3046 && DECL_TI_TEMPLATE (decl))
3047 tmpl = DECL_TI_TEMPLATE (decl);
3048 /* If DECL is a TYPE_DECL for a class-template, then there won't
3049 be DECL_LANG_SPECIFIC. The information equivalent to
3050 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3051 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3052 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3053 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3055 /* Since a template declaration already existed for this
3056 class-type, we must be redeclaring it here. Make sure
3057 that the redeclaration is valid. */
3058 redeclare_class_template (TREE_TYPE (decl),
3059 current_template_parms);
3060 /* We don't need to create a new TEMPLATE_DECL; just use the
3061 one we already had. */
3062 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3066 tmpl = build_template_decl (decl, current_template_parms,
3070 if (DECL_LANG_SPECIFIC (decl)
3071 && DECL_TEMPLATE_SPECIALIZATION (decl))
3073 /* A specialization of a member template of a template
3075 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3076 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3077 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3083 tree a, t, current, parms;
3086 if (TREE_CODE (decl) == TYPE_DECL)
3088 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3089 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3090 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3091 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3092 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3095 error ("%qD does not declare a template type", decl);
3099 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3101 error ("template definition of non-template %q#D", decl);
3105 tmpl = DECL_TI_TEMPLATE (decl);
3107 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3108 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3109 && DECL_TEMPLATE_SPECIALIZATION (decl)
3110 && DECL_MEMBER_TEMPLATE_P (tmpl))
3114 /* The declaration is a specialization of a member
3115 template, declared outside the class. Therefore, the
3116 innermost template arguments will be NULL, so we
3117 replace them with the arguments determined by the
3118 earlier call to check_explicit_specialization. */
3119 args = DECL_TI_ARGS (decl);
3122 = build_template_decl (decl, current_template_parms,
3124 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3125 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3126 DECL_TI_TEMPLATE (decl) = new_tmpl;
3127 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3128 DECL_TEMPLATE_INFO (new_tmpl)
3129 = tree_cons (tmpl, args, NULL_TREE);
3131 register_specialization (new_tmpl,
3132 most_general_template (tmpl),
3138 /* Make sure the template headers we got make sense. */
3140 parms = DECL_TEMPLATE_PARMS (tmpl);
3141 i = TMPL_PARMS_DEPTH (parms);
3142 if (TMPL_ARGS_DEPTH (args) != i)
3144 error ("expected %d levels of template parms for %q#D, got %d",
3145 i, decl, TMPL_ARGS_DEPTH (args));
3148 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3150 a = TMPL_ARGS_LEVEL (args, i);
3151 t = INNERMOST_TEMPLATE_PARMS (parms);
3153 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3155 if (current == decl)
3156 error ("got %d template parameters for %q#D",
3157 TREE_VEC_LENGTH (a), decl);
3159 error ("got %d template parameters for %q#T",
3160 TREE_VEC_LENGTH (a), current);
3161 error (" but %d required", TREE_VEC_LENGTH (t));
3162 return error_mark_node;
3165 /* Perhaps we should also check that the parms are used in the
3166 appropriate qualifying scopes in the declarator? */
3168 if (current == decl)
3171 current = TYPE_CONTEXT (current);
3175 DECL_TEMPLATE_RESULT (tmpl) = decl;
3176 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3178 /* Push template declarations for global functions and types. Note
3179 that we do not try to push a global template friend declared in a
3180 template class; such a thing may well depend on the template
3181 parameters of the class. */
3182 if (new_template_p && !ctx
3183 && !(is_friend && template_class_depth (current_class_type) > 0))
3185 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3186 if (tmpl == error_mark_node)
3187 return error_mark_node;
3189 /* Hide template friend classes that haven't been declared yet. */
3190 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3192 DECL_ANTICIPATED (tmpl) = 1;
3193 DECL_FRIEND_P (tmpl) = 1;
3199 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3200 if (DECL_CONV_FN_P (tmpl))
3202 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3204 /* It is a conversion operator. See if the type converted to
3205 depends on innermost template operands. */
3207 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3209 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3213 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3214 back to its most general template. If TMPL is a specialization,
3215 ARGS may only have the innermost set of arguments. Add the missing
3216 argument levels if necessary. */
3217 if (DECL_TEMPLATE_INFO (tmpl))
3218 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3220 info = tree_cons (tmpl, args, NULL_TREE);
3222 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3224 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3225 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3226 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3227 /* Don't change the name if we've already set it up. */
3228 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3229 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3231 else if (DECL_LANG_SPECIFIC (decl))
3232 DECL_TEMPLATE_INFO (decl) = info;
3234 return DECL_TEMPLATE_RESULT (tmpl);
3238 push_template_decl (tree decl)
3240 return push_template_decl_real (decl, false);
3243 /* Called when a class template TYPE is redeclared with the indicated
3244 template PARMS, e.g.:
3246 template <class T> struct S;
3247 template <class T> struct S {}; */
3250 redeclare_class_template (tree type, tree parms)
3256 if (!TYPE_TEMPLATE_INFO (type))
3258 error ("%qT is not a template type", type);
3262 tmpl = TYPE_TI_TEMPLATE (type);
3263 if (!PRIMARY_TEMPLATE_P (tmpl))
3264 /* The type is nested in some template class. Nothing to worry
3265 about here; there are no new template parameters for the nested
3271 error ("template specifiers not specified in declaration of %qD",
3276 parms = INNERMOST_TEMPLATE_PARMS (parms);
3277 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3279 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3281 error ("previous declaration %q+D", tmpl);
3282 error ("used %d template parameter(s) instead of %d",
3283 TREE_VEC_LENGTH (tmpl_parms),
3284 TREE_VEC_LENGTH (parms));
3288 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3290 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3291 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3292 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3293 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3295 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3297 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3298 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3299 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3301 error ("template parameter %q+#D", tmpl_parm);
3302 error ("redeclared here as %q#D", parm);
3306 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3308 /* We have in [temp.param]:
3310 A template-parameter may not be given default arguments
3311 by two different declarations in the same scope. */
3312 error ("redefinition of default argument for %q#D", parm);
3313 error ("%J original definition appeared here", tmpl_parm);
3317 if (parm_default != NULL_TREE)
3318 /* Update the previous template parameters (which are the ones
3319 that will really count) with the new default value. */
3320 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3321 else if (tmpl_default != NULL_TREE)
3322 /* Update the new parameters, too; they'll be used as the
3323 parameters for any members. */
3324 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3328 /* Simplify EXPR if it is a non-dependent expression. Returns the
3329 (possibly simplified) expression. */
3332 fold_non_dependent_expr (tree expr)
3334 /* If we're in a template, but EXPR isn't value dependent, simplify
3335 it. We're supposed to treat:
3337 template <typename T> void f(T[1 + 1]);
3338 template <typename T> void f(T[2]);
3340 as two declarations of the same function, for example. */
3341 if (processing_template_decl
3342 && !type_dependent_expression_p (expr)
3343 && !value_dependent_expression_p (expr))
3345 HOST_WIDE_INT saved_processing_template_decl;
3347 saved_processing_template_decl = processing_template_decl;
3348 processing_template_decl = 0;
3349 expr = tsubst_copy_and_build (expr,
3352 /*in_decl=*/NULL_TREE,
3353 /*function_p=*/false);
3354 processing_template_decl = saved_processing_template_decl;
3359 /* EXPR is an expression which is used in a constant-expression context.
3360 For instance, it could be a VAR_DECL with a constant initializer.
3361 Extract the innest constant expression.
3363 This is basically a more powerful version of
3364 integral_constant_value, which can be used also in templates where
3365 initializers can maintain a syntactic rather than semantic form
3366 (even if they are non-dependent, for access-checking purposes). */
3369 fold_decl_constant_value (tree expr)
3371 tree const_expr = expr;
3374 expr = fold_non_dependent_expr (const_expr);
3375 const_expr = integral_constant_value (expr);
3377 while (expr != const_expr);
3382 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3383 must be a function or a pointer-to-function type, as specified
3384 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3385 and check that the resulting function has external linkage. */
3388 convert_nontype_argument_function (tree type, tree expr)
3393 fn = instantiate_type (type, fns, tf_none);
3394 if (fn == error_mark_node)
3395 return error_mark_node;
3398 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3399 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3401 /* [temp.arg.nontype]/1
3403 A template-argument for a non-type, non-template template-parameter
3406 -- the address of an object or function with external linkage. */
3407 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3409 error ("%qE is not a valid template argument for type %qT "
3410 "because function %qD has not external linkage",
3411 expr, type, fn_no_ptr);
3418 /* Attempt to convert the non-type template parameter EXPR to the
3419 indicated TYPE. If the conversion is successful, return the
3420 converted value. If the conversion is unsuccessful, return
3421 NULL_TREE if we issued an error message, or error_mark_node if we
3422 did not. We issue error messages for out-and-out bad template
3423 parameters, but not simply because the conversion failed, since we
3424 might be just trying to do argument deduction. Both TYPE and EXPR
3425 must be non-dependent.
3427 The conversion follows the special rules described in
3428 [temp.arg.nontype], and it is much more strict than an implicit
3431 This function is called twice for each template argument (see
3432 lookup_template_class for a more accurate description of this
3433 problem). This means that we need to handle expressions which
3434 are not valid in a C++ source, but can be created from the
3435 first call (for instance, casts to perform conversions). These
3436 hacks can go away after we fix the double coercion problem. */
3439 convert_nontype_argument (tree type, tree expr)
3443 /* Detect immediately string literals as invalid non-type argument.
3444 This special-case is not needed for correctness (we would easily
3445 catch this later), but only to provide better diagnostic for this
3446 common user mistake. As suggested by DR 100, we do not mention
3447 linkage issues in the diagnostic as this is not the point. */
3448 if (TREE_CODE (expr) == STRING_CST)
3450 error ("%qE is not a valid template argument for type %qT "
3451 "because string literals can never be used in this context",
3456 /* If we are in a template, EXPR may be non-dependent, but still
3457 have a syntactic, rather than semantic, form. For example, EXPR
3458 might be a SCOPE_REF, rather than the VAR_DECL to which the
3459 SCOPE_REF refers. Preserving the qualifying scope is necessary
3460 so that access checking can be performed when the template is
3461 instantiated -- but here we need the resolved form so that we can
3462 convert the argument. */
3463 expr = fold_non_dependent_expr (expr);
3464 if (error_operand_p (expr))
3465 return error_mark_node;
3466 expr_type = TREE_TYPE (expr);
3468 /* HACK: Due to double coercion, we can get a
3469 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3470 which is the tree that we built on the first call (see
3471 below when coercing to reference to object or to reference to
3472 function). We just strip everything and get to the arg.
3473 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3475 if (TREE_CODE (expr) == NOP_EXPR)
3477 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3479 /* ??? Maybe we could use convert_from_reference here, but we
3480 would need to relax its constraints because the NOP_EXPR
3481 could actually change the type to something more cv-qualified,
3482 and this is not folded by convert_from_reference. */
3483 tree addr = TREE_OPERAND (expr, 0);
3484 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3485 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3486 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3487 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3488 (TREE_TYPE (expr_type),
3489 TREE_TYPE (TREE_TYPE (addr))));
3491 expr = TREE_OPERAND (addr, 0);
3492 expr_type = TREE_TYPE (expr);
3495 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3496 parameter is a pointer to object, through decay and
3497 qualification conversion. Let's strip everything. */
3498 else if (TYPE_PTROBV_P (type))
3501 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3502 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3503 /* Skip the ADDR_EXPR only if it is part of the decay for
3504 an array. Otherwise, it is part of the original argument
3505 in the source code. */
3506 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3507 expr = TREE_OPERAND (expr, 0);
3508 expr_type = TREE_TYPE (expr);
3512 /* [temp.arg.nontype]/5, bullet 1
3514 For a non-type template-parameter of integral or enumeration type,
3515 integral promotions (_conv.prom_) and integral conversions
3516 (_conv.integral_) are applied. */
3517 if (INTEGRAL_TYPE_P (type))
3519 if (!INTEGRAL_TYPE_P (expr_type))
3520 return error_mark_node;
3522 expr = fold_decl_constant_value (expr);
3523 /* Notice that there are constant expressions like '4 % 0' which
3524 do not fold into integer constants. */
3525 if (TREE_CODE (expr) != INTEGER_CST)
3527 error ("%qE is not a valid template argument for type %qT "
3528 "because it is a non-constant expression", expr, type);
3532 /* At this point, an implicit conversion does what we want,
3533 because we already know that the expression is of integral
3535 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3536 if (expr == error_mark_node)
3537 return error_mark_node;
3539 /* Conversion was allowed: fold it to a bare integer constant. */
3542 /* [temp.arg.nontype]/5, bullet 2
3544 For a non-type template-parameter of type pointer to object,
3545 qualification conversions (_conv.qual_) and the array-to-pointer
3546 conversion (_conv.array_) are applied. */
3547 else if (TYPE_PTROBV_P (type))
3549 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3551 A template-argument for a non-type, non-template template-parameter
3552 shall be one of: [...]
3554 -- the name of a non-type template-parameter;
3555 -- the address of an object or function with external linkage, [...]
3556 expressed as "& id-expression" where the & is optional if the name
3557 refers to a function or array, or if the corresponding
3558 template-parameter is a reference.
3560 Here, we do not care about functions, as they are invalid anyway
3561 for a parameter of type pointer-to-object. */
3562 bool constant_address_p =
3563 (TREE_CODE (expr) == ADDR_EXPR
3564 || TREE_CODE (expr_type) == ARRAY_TYPE
3565 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3567 expr = decay_conversion (expr);
3568 if (expr == error_mark_node)
3569 return error_mark_node;
3571 expr = perform_qualification_conversions (type, expr);
3572 if (expr == error_mark_node)
3573 return error_mark_node;
3575 if (!constant_address_p)
3577 error ("%qE is not a valid template argument for type %qT "
3578 "because it is not a constant pointer", expr, type);
3582 /* [temp.arg.nontype]/5, bullet 3
3584 For a non-type template-parameter of type reference to object, no
3585 conversions apply. The type referred to by the reference may be more
3586 cv-qualified than the (otherwise identical) type of the
3587 template-argument. The template-parameter is bound directly to the
3588 template-argument, which must be an lvalue. */
3589 else if (TYPE_REF_OBJ_P (type))
3591 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3593 return error_mark_node;
3595 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3597 error ("%qE is not a valid template argument for type %qT "
3598 "because of conflicts in cv-qualification", expr, type);
3602 if (!real_lvalue_p (expr))
3604 error ("%qE is not a valid template argument for type %qT "
3605 "because it is not a lvalue", expr, type);
3609 /* [temp.arg.nontype]/1
3611 A template-argument for a non-type, non-template template-parameter
3612 shall be one of: [...]
3614 -- the address of an object or function with external linkage. */
3615 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3617 error ("%qE is not a valid template argument for type %qT "
3618 "because object %qD has not external linkage",
3623 expr = build_nop (type, build_address (expr));
3625 /* [temp.arg.nontype]/5, bullet 4
3627 For a non-type template-parameter of type pointer to function, only
3628 the function-to-pointer conversion (_conv.func_) is applied. If the
3629 template-argument represents a set of overloaded functions (or a
3630 pointer to such), the matching function is selected from the set
3632 else if (TYPE_PTRFN_P (type))
3634 /* If the argument is a template-id, we might not have enough
3635 context information to decay the pointer. */
3636 if (!type_unknown_p (expr_type))
3638 expr = decay_conversion (expr);
3639 if (expr == error_mark_node)
3640 return error_mark_node;
3643 expr = convert_nontype_argument_function (type, expr);
3644 if (!expr || expr == error_mark_node)
3647 /* [temp.arg.nontype]/5, bullet 5
3649 For a non-type template-parameter of type reference to function, no
3650 conversions apply. If the template-argument represents a set of
3651 overloaded functions, the matching function is selected from the set
3653 else if (TYPE_REFFN_P (type))
3655 if (TREE_CODE (expr) == ADDR_EXPR)
3657 error ("%qE is not a valid template argument for type %qT "
3658 "because it is a pointer", expr, type);
3659 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3663 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3664 if (!expr || expr == error_mark_node)
3667 expr = build_nop (type, build_address (expr));
3669 /* [temp.arg.nontype]/5, bullet 6
3671 For a non-type template-parameter of type pointer to member function,
3672 no conversions apply. If the template-argument represents a set of
3673 overloaded member functions, the matching member function is selected
3674 from the set (_over.over_). */
3675 else if (TYPE_PTRMEMFUNC_P (type))
3677 expr = instantiate_type (type, expr, tf_none);
3678 if (expr == error_mark_node)
3679 return error_mark_node;
3681 /* There is no way to disable standard conversions in
3682 resolve_address_of_overloaded_function (called by
3683 instantiate_type). It is possible that the call succeeded by
3684 converting &B::I to &D::I (where B is a base of D), so we need
3685 to reject this conversion here.
3687 Actually, even if there was a way to disable standard conversions,
3688 it would still be better to reject them here so that we can
3689 provide a superior diagnostic. */
3690 if (!same_type_p (TREE_TYPE (expr), type))
3692 /* Make sure we are just one standard conversion off. */
3693 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3694 error ("%qE is not a valid template argument for type %qT "
3695 "because it is of type %qT", expr, type,
3697 inform ("standard conversions are not allowed in this context");
3701 /* [temp.arg.nontype]/5, bullet 7
3703 For a non-type template-parameter of type pointer to data member,
3704 qualification conversions (_conv.qual_) are applied. */
3705 else if (TYPE_PTRMEM_P (type))
3707 expr = perform_qualification_conversions (type, expr);
3708 if (expr == error_mark_node)
3711 /* A template non-type parameter must be one of the above. */
3715 /* Sanity check: did we actually convert the argument to the
3717 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3722 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3723 template template parameters. Both PARM_PARMS and ARG_PARMS are
3724 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3727 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3728 the case, then extra parameters must have default arguments.
3730 Consider the example:
3731 template <class T, class Allocator = allocator> class vector;
3732 template<template <class U> class TT> class C;
3734 C<vector> is a valid instantiation. PARM_PARMS for the above code
3735 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3736 T and Allocator) and OUTER_ARGS contains the argument that is used to
3737 substitute the TT parameter. */
3740 coerce_template_template_parms (tree parm_parms,
3742 tsubst_flags_t complain,
3746 int nparms, nargs, i;
3749 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3750 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3752 nparms = TREE_VEC_LENGTH (parm_parms);
3753 nargs = TREE_VEC_LENGTH (arg_parms);
3755 /* The rule here is opposite of coerce_template_parms. */
3758 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3761 for (i = 0; i < nparms; ++i)
3763 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3764 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3766 if (arg == NULL_TREE || arg == error_mark_node
3767 || parm == NULL_TREE || parm == error_mark_node)
3770 if (TREE_CODE (arg) != TREE_CODE (parm))
3773 switch (TREE_CODE (parm))
3779 /* We encounter instantiations of templates like
3780 template <template <template <class> class> class TT>
3783 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3784 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3786 if (!coerce_template_template_parms
3787 (parmparm, argparm, complain, in_decl, outer_args))
3793 /* The tsubst call is used to handle cases such as
3795 template <int> class C {};
3796 template <class T, template <T> class TT> class D {};
3799 i.e. the parameter list of TT depends on earlier parameters. */
3800 if (!dependent_type_p (TREE_TYPE (arg))
3802 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3814 /* Convert the indicated template ARG as necessary to match the
3815 indicated template PARM. Returns the converted ARG, or
3816 error_mark_node if the conversion was unsuccessful. Error and
3817 warning messages are issued under control of COMPLAIN. This
3818 conversion is for the Ith parameter in the parameter list. ARGS is
3819 the full set of template arguments deduced so far. */
3822 convert_template_argument (tree parm,
3825 tsubst_flags_t complain,
3831 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3833 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3835 if (TREE_CODE (arg) == TREE_LIST
3836 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3838 /* The template argument was the name of some
3839 member function. That's usually
3840 invalid, but static members are OK. In any
3841 case, grab the underlying fields/functions
3842 and issue an error later if required. */
3843 arg = TREE_VALUE (arg);
3844 TREE_TYPE (arg) = unknown_type_node;
3847 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3848 requires_type = (TREE_CODE (parm) == TYPE_DECL
3849 || requires_tmpl_type);
3851 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3852 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3853 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3854 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3857 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3858 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3859 arg = TYPE_STUB_DECL (arg);
3861 is_type = TYPE_P (arg) || is_tmpl_type;
3863 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3864 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3866 pedwarn ("to refer to a type member of a template parameter, "
3867 "use %<typename %E%>", arg);
3869 arg = make_typename_type (TREE_OPERAND (arg, 0),
3870 TREE_OPERAND (arg, 1),
3872 complain & tf_error);
3875 if (is_type != requires_type)
3879 if (complain & tf_error)
3881 error ("type/value mismatch at argument %d in template "
3882 "parameter list for %qD",
3885 error (" expected a constant of type %qT, got %qT",
3887 (is_tmpl_type ? DECL_NAME (arg) : arg));
3888 else if (requires_tmpl_type)
3889 error (" expected a class template, got %qE", arg);
3891 error (" expected a type, got %qE", arg);
3894 return error_mark_node;
3896 if (is_tmpl_type ^ requires_tmpl_type)
3898 if (in_decl && (complain & tf_error))
3900 error ("type/value mismatch at argument %d in template "
3901 "parameter list for %qD",
3904 error (" expected a type, got %qT", DECL_NAME (arg));
3906 error (" expected a class template, got %qT", arg);
3908 return error_mark_node;
3913 if (requires_tmpl_type)
3915 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3916 /* The number of argument required is not known yet.
3917 Just accept it for now. */
3918 val = TREE_TYPE (arg);
3921 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3922 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3924 if (coerce_template_template_parms (parmparm, argparm,
3930 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3932 if (val != error_mark_node
3933 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3934 val = TREE_TYPE (val);
3938 if (in_decl && (complain & tf_error))
3940 error ("type/value mismatch at argument %d in "
3941 "template parameter list for %qD",
3943 error (" expected a template of type %qD, got %qD",
3947 val = error_mark_node;
3953 /* We only form one instance of each template specialization.
3954 Therefore, if we use a non-canonical variant (i.e., a
3955 typedef), any future messages referring to the type will use
3956 the typedef, which is confusing if those future uses do not
3957 themselves also use the typedef. */
3959 val = canonical_type_variant (val);
3963 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3965 if (invalid_nontype_parm_type_p (t, complain))
3966 return error_mark_node;
3968 if (!uses_template_parms (arg) && !uses_template_parms (t))
3969 /* We used to call digest_init here. However, digest_init
3970 will report errors, which we don't want when complain
3971 is zero. More importantly, digest_init will try too
3972 hard to convert things: for example, `0' should not be
3973 converted to pointer type at this point according to
3974 the standard. Accepting this is not merely an
3975 extension, since deciding whether or not these
3976 conversions can occur is part of determining which
3977 function template to call, or whether a given explicit
3978 argument specification is valid. */
3979 val = convert_nontype_argument (t, arg);
3983 if (val == NULL_TREE)
3984 val = error_mark_node;
3985 else if (val == error_mark_node && (complain & tf_error))
3986 error ("could not convert template argument %qE to %qT", arg, t);
3992 /* Convert all template arguments to their appropriate types, and
3993 return a vector containing the innermost resulting template
3994 arguments. If any error occurs, return error_mark_node. Error and
3995 warning messages are issued under control of COMPLAIN.
3997 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3998 provided in ARGLIST, or else trailing parameters must have default
3999 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
4000 deduction for any unspecified trailing arguments. */
4003 coerce_template_parms (tree parms,
4006 tsubst_flags_t complain,
4007 int require_all_arguments)
4009 int nparms, nargs, i, lost = 0;
4012 tree new_inner_args;
4014 inner_args = INNERMOST_TEMPLATE_ARGS (args);
4015 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4016 nparms = TREE_VEC_LENGTH (parms);
4020 && require_all_arguments
4021 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
4023 if (complain & tf_error)
4025 error ("wrong number of template arguments (%d, should be %d)",
4029 error ("provided for %q+D", in_decl);
4032 return error_mark_node;
4035 new_inner_args = make_tree_vec (nparms);
4036 new_args = add_outermost_template_args (args, new_inner_args);
4037 for (i = 0; i < nparms; i++)
4042 /* Get the Ith template parameter. */
4043 parm = TREE_VEC_ELT (parms, i);
4045 /* Calculate the Ith argument. */
4047 arg = TREE_VEC_ELT (inner_args, i);
4048 else if (require_all_arguments)
4049 /* There must be a default arg in this case. */
4050 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4056 if (arg == error_mark_node)
4058 if (complain & tf_error)
4059 error ("template argument %d is invalid", i + 1);
4062 arg = convert_template_argument (TREE_VALUE (parm),
4063 arg, new_args, complain, i,
4066 if (arg == error_mark_node)
4068 TREE_VEC_ELT (new_inner_args, i) = arg;
4072 return error_mark_node;
4074 return new_inner_args;
4077 /* Returns 1 if template args OT and NT are equivalent. */
4080 template_args_equal (tree ot, tree nt)
4085 if (TREE_CODE (nt) == TREE_VEC)
4086 /* For member templates */
4087 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4088 else if (TYPE_P (nt))
4089 return TYPE_P (ot) && same_type_p (ot, nt);
4090 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4093 return cp_tree_equal (ot, nt);
4096 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4097 of template arguments. Returns 0 otherwise. */
4100 comp_template_args (tree oldargs, tree newargs)
4104 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4107 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4109 tree nt = TREE_VEC_ELT (newargs, i);
4110 tree ot = TREE_VEC_ELT (oldargs, i);
4112 if (! template_args_equal (ot, nt))
4118 /* Given class template name and parameter list, produce a user-friendly name
4119 for the instantiation. */
4122 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4124 static struct obstack scratch_obstack;
4125 static char *scratch_firstobj;
4128 if (!scratch_firstobj)
4129 gcc_obstack_init (&scratch_obstack);
4131 obstack_free (&scratch_obstack, scratch_firstobj);
4132 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4134 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4135 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4139 nparms = TREE_VEC_LENGTH (parms);
4140 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4141 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4142 for (i = 0; i < nparms; i++)
4144 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4145 tree arg = TREE_VEC_ELT (arglist, i);
4150 if (TREE_CODE (parm) == TYPE_DECL)
4152 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4155 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4157 if (TREE_CODE (arg) == TEMPLATE_DECL)
4159 /* Already substituted with real template. Just output
4160 the template name here */
4161 tree context = DECL_CONTEXT (arg);
4164 /* The template may be defined in a namespace, or
4165 may be a member template. */
4166 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4167 || CLASS_TYPE_P (context));
4168 cat (decl_as_string (DECL_CONTEXT (arg),
4169 TFF_PLAIN_IDENTIFIER));
4172 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4175 /* Output the parameter declaration. */
4176 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4180 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4182 /* No need to check arglist against parmlist here; we did that
4183 in coerce_template_parms, called from lookup_template_class. */
4184 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4187 char *bufp = obstack_next_free (&scratch_obstack);
4189 while (bufp[offset - 1] == ' ')
4191 obstack_blank_fast (&scratch_obstack, offset);
4193 /* B<C<char> >, not B<C<char>> */
4194 if (bufp[offset - 1] == '>')
4199 return (char *) obstack_base (&scratch_obstack);
4203 classtype_mangled_name (tree t)
4205 if (CLASSTYPE_TEMPLATE_INFO (t)
4206 /* Specializations have already had their names set up in
4207 lookup_template_class. */
4208 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4210 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4212 /* For non-primary templates, the template parameters are
4213 implicit from their surrounding context. */
4214 if (PRIMARY_TEMPLATE_P (tmpl))
4216 tree name = DECL_NAME (tmpl);
4217 char *mangled_name = mangle_class_name_for_template
4218 (IDENTIFIER_POINTER (name),
4219 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4220 CLASSTYPE_TI_ARGS (t));
4221 tree id = get_identifier (mangled_name);
4222 IDENTIFIER_TEMPLATE (id) = name;
4227 return TYPE_IDENTIFIER (t);
4231 add_pending_template (tree d)
4233 tree ti = (TYPE_P (d)
4234 ? CLASSTYPE_TEMPLATE_INFO (d)
4235 : DECL_TEMPLATE_INFO (d));
4239 if (TI_PENDING_TEMPLATE_FLAG (ti))
4242 /* We are called both from instantiate_decl, where we've already had a
4243 tinst_level pushed, and instantiate_template, where we haven't.
4245 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4248 push_tinst_level (d);
4250 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4251 if (last_pending_template)
4252 TREE_CHAIN (last_pending_template) = pt;
4254 pending_templates = pt;
4256 last_pending_template = pt;
4258 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4265 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4266 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4267 documentation for TEMPLATE_ID_EXPR. */
4270 lookup_template_function (tree fns, tree arglist)
4274 if (fns == error_mark_node || arglist == error_mark_node)
4275 return error_mark_node;
4277 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4278 gcc_assert (fns && (is_overloaded_fn (fns)
4279 || TREE_CODE (fns) == IDENTIFIER_NODE));
4281 if (BASELINK_P (fns))
4283 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4285 BASELINK_FUNCTIONS (fns),
4290 type = TREE_TYPE (fns);
4291 if (TREE_CODE (fns) == OVERLOAD || !type)
4292 type = unknown_type_node;
4294 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4297 /* Within the scope of a template class S<T>, the name S gets bound
4298 (in build_self_reference) to a TYPE_DECL for the class, not a
4299 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4300 or one of its enclosing classes, and that type is a template,
4301 return the associated TEMPLATE_DECL. Otherwise, the original
4302 DECL is returned. */
4305 maybe_get_template_decl_from_type_decl (tree decl)
4307 return (decl != NULL_TREE
4308 && TREE_CODE (decl) == TYPE_DECL
4309 && DECL_ARTIFICIAL (decl)
4310 && CLASS_TYPE_P (TREE_TYPE (decl))
4311 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4312 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4315 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4316 parameters, find the desired type.
4318 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4320 IN_DECL, if non-NULL, is the template declaration we are trying to
4323 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4324 the class we are looking up.
4326 Issue error and warning messages under control of COMPLAIN.
4328 If the template class is really a local class in a template
4329 function, then the FUNCTION_CONTEXT is the function in which it is
4332 ??? Note that this function is currently called *twice* for each
4333 template-id: the first time from the parser, while creating the
4334 incomplete type (finish_template_type), and the second type during the
4335 real instantiation (instantiate_template_class). This is surely something
4336 that we want to avoid. It also causes some problems with argument
4337 coercion (see convert_nontype_argument for more information on this). */
4340 lookup_template_class (tree d1,
4345 tsubst_flags_t complain)
4347 tree template = NULL_TREE, parmlist;
4350 timevar_push (TV_NAME_LOOKUP);
4352 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4354 tree value = innermost_non_namespace_value (d1);
4355 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4360 push_decl_namespace (context);
4361 template = lookup_name (d1, /*prefer_type=*/0);
4362 template = maybe_get_template_decl_from_type_decl (template);
4364 pop_decl_namespace ();
4367 context = DECL_CONTEXT (template);
4369 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4371 tree type = TREE_TYPE (d1);
4373 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4374 an implicit typename for the second A. Deal with it. */
4375 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4376 type = TREE_TYPE (type);
4378 if (CLASSTYPE_TEMPLATE_INFO (type))
4380 template = CLASSTYPE_TI_TEMPLATE (type);
4381 d1 = DECL_NAME (template);
4384 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4385 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4387 template = TYPE_TI_TEMPLATE (d1);
4388 d1 = DECL_NAME (template);
4390 else if (TREE_CODE (d1) == TEMPLATE_DECL
4391 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4394 d1 = DECL_NAME (template);
4395 context = DECL_CONTEXT (template);
4398 /* Issue an error message if we didn't find a template. */
4401 if (complain & tf_error)
4402 error ("%qT is not a template", d1);
4403 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4406 if (TREE_CODE (template) != TEMPLATE_DECL
4407 /* Make sure it's a user visible template, if it was named by
4409 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4410 && !PRIMARY_TEMPLATE_P (template)))
4412 if (complain & tf_error)
4414 error ("non-template type %qT used as a template", d1);
4416 error ("for template declaration %q+D", in_decl);
4418 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4421 complain &= ~tf_user;
4423 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4425 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4426 template arguments */
4431 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4433 /* Consider an example where a template template parameter declared as
4435 template <class T, class U = std::allocator<T> > class TT
4437 The template parameter level of T and U are one level larger than
4438 of TT. To proper process the default argument of U, say when an
4439 instantiation `TT<int>' is seen, we need to build the full
4440 arguments containing {int} as the innermost level. Outer levels,
4441 available when not appearing as default template argument, can be
4442 obtained from `current_template_args ()'.
4444 Suppose that TT is later substituted with std::vector. The above
4445 instantiation is `TT<int, std::allocator<T> >' with TT at
4446 level 1, and T at level 2, while the template arguments at level 1
4447 becomes {std::vector} and the inner level 2 is {int}. */
4449 if (current_template_parms)
4450 arglist = add_to_template_args (current_template_args (), arglist);
4452 arglist2 = coerce_template_parms (parmlist, arglist, template,
4453 complain, /*require_all_args=*/1);
4454 if (arglist2 == error_mark_node
4455 || (!uses_template_parms (arglist2)
4456 && check_instantiated_args (template, arglist2, complain)))
4457 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4459 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4460 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4464 tree template_type = TREE_TYPE (template);
4467 tree found = NULL_TREE;
4470 int is_partial_instantiation;
4472 gen_tmpl = most_general_template (template);
4473 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4474 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4475 arg_depth = TMPL_ARGS_DEPTH (arglist);
4477 if (arg_depth == 1 && parm_depth > 1)
4479 /* We've been given an incomplete set of template arguments.
4482 template <class T> struct S1 {
4483 template <class U> struct S2 {};
4484 template <class U> struct S2<U*> {};
4487 we will be called with an ARGLIST of `U*', but the
4488 TEMPLATE will be `template <class T> template
4489 <class U> struct S1<T>::S2'. We must fill in the missing
4492 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4494 arg_depth = TMPL_ARGS_DEPTH (arglist);
4497 /* Now we should have enough arguments. */
4498 gcc_assert (parm_depth == arg_depth);
4500 /* From here on, we're only interested in the most general
4502 template = gen_tmpl;
4504 /* Calculate the BOUND_ARGS. These will be the args that are
4505 actually tsubst'd into the definition to create the
4509 /* We have multiple levels of arguments to coerce, at once. */
4511 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4513 tree bound_args = make_tree_vec (parm_depth);
4515 for (i = saved_depth,
4516 t = DECL_TEMPLATE_PARMS (template);
4517 i > 0 && t != NULL_TREE;
4518 --i, t = TREE_CHAIN (t))
4520 tree a = coerce_template_parms (TREE_VALUE (t),
4522 complain, /*require_all_args=*/1);
4524 /* Don't process further if one of the levels fails. */
4525 if (a == error_mark_node)
4527 /* Restore the ARGLIST to its full size. */
4528 TREE_VEC_LENGTH (arglist) = saved_depth;
4529 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4532 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4534 /* We temporarily reduce the length of the ARGLIST so
4535 that coerce_template_parms will see only the arguments
4536 corresponding to the template parameters it is
4538 TREE_VEC_LENGTH (arglist)--;
4541 /* Restore the ARGLIST to its full size. */
4542 TREE_VEC_LENGTH (arglist) = saved_depth;
4544 arglist = bound_args;
4548 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4549 INNERMOST_TEMPLATE_ARGS (arglist),
4551 complain, /*require_all_args=*/1);
4553 if (arglist == error_mark_node)
4554 /* We were unable to bind the arguments. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4557 /* In the scope of a template class, explicit references to the
4558 template class refer to the type of the template, not any
4559 instantiation of it. For example, in:
4561 template <class T> class C { void f(C<T>); }
4563 the `C<T>' is just the same as `C'. Outside of the
4564 class, however, such a reference is an instantiation. */
4565 if (comp_template_args (TYPE_TI_ARGS (template_type),
4568 found = template_type;
4570 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4574 for (ctx = current_class_type;
4575 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4577 ? TYPE_CONTEXT (ctx)
4578 : DECL_CONTEXT (ctx)))
4579 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4582 /* We're not in the scope of the class, so the
4583 TEMPLATE_TYPE is not the type we want after all. */
4589 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4591 /* If we already have this specialization, return it. */
4592 found = retrieve_specialization (template, arglist,
4593 /*class_specializations_p=*/false);
4595 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4597 /* This type is a "partial instantiation" if any of the template
4598 arguments still involve template parameters. Note that we set
4599 IS_PARTIAL_INSTANTIATION for partial specializations as
4601 is_partial_instantiation = uses_template_parms (arglist);
4603 /* If the deduced arguments are invalid, then the binding
4605 if (!is_partial_instantiation
4606 && check_instantiated_args (template,
4607 INNERMOST_TEMPLATE_ARGS (arglist),
4609 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4611 if (!is_partial_instantiation
4612 && !PRIMARY_TEMPLATE_P (template)
4613 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4615 found = xref_tag_from_type (TREE_TYPE (template),
4616 DECL_NAME (template),
4617 /*tag_scope=*/ts_global);
4618 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4621 context = tsubst (DECL_CONTEXT (template), arglist,
4624 context = global_namespace;
4626 /* Create the type. */
4627 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4629 if (!is_partial_instantiation)
4631 set_current_access_from_decl (TYPE_NAME (template_type));
4632 t = start_enum (TYPE_IDENTIFIER (template_type));
4635 /* We don't want to call start_enum for this type, since
4636 the values for the enumeration constants may involve
4637 template parameters. And, no one should be interested
4638 in the enumeration constants for such a type. */
4639 t = make_node (ENUMERAL_TYPE);
4643 t = make_aggr_type (TREE_CODE (template_type));
4644 CLASSTYPE_DECLARED_CLASS (t)
4645 = CLASSTYPE_DECLARED_CLASS (template_type);
4646 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4647 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4649 /* A local class. Make sure the decl gets registered properly. */
4650 if (context == current_function_decl)
4651 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4654 /* If we called start_enum or pushtag above, this information
4655 will already be set up. */
4658 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4660 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4661 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4662 TYPE_STUB_DECL (t) = type_decl;
4663 DECL_SOURCE_LOCATION (type_decl)
4664 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4667 type_decl = TYPE_NAME (t);
4669 TREE_PRIVATE (type_decl)
4670 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4671 TREE_PROTECTED (type_decl)
4672 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4673 DECL_IN_SYSTEM_HEADER (type_decl)
4674 = DECL_IN_SYSTEM_HEADER (template);
4675 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4677 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4678 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4681 /* Set up the template information. We have to figure out which
4682 template is the immediate parent if this is a full
4684 if (parm_depth == 1 || is_partial_instantiation
4685 || !PRIMARY_TEMPLATE_P (template))
4686 /* This case is easy; there are no member templates involved. */
4690 /* This is a full instantiation of a member template. Look
4691 for a partial instantiation of which this is an instance. */
4693 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4694 found; found = TREE_CHAIN (found))
4697 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4699 /* We only want partial instantiations, here, not
4700 specializations or full instantiations. */
4701 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4702 || !uses_template_parms (TREE_VALUE (found)))
4705 /* Temporarily reduce by one the number of levels in the
4706 ARGLIST and in FOUND so as to avoid comparing the
4707 last set of arguments. */
4708 TREE_VEC_LENGTH (arglist)--;
4709 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4711 /* See if the arguments match. If they do, then TMPL is
4712 the partial instantiation we want. */
4713 success = comp_template_args (TREE_PURPOSE (found), arglist);
4715 /* Restore the argument vectors to their full size. */
4716 TREE_VEC_LENGTH (arglist)++;
4717 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4728 /* There was no partial instantiation. This happens
4729 where C<T> is a member template of A<T> and it's used
4732 template <typename T> struct B { A<T>::C<int> m; };
4735 Create the partial instantiation.
4737 TREE_VEC_LENGTH (arglist)--;
4738 found = tsubst (template, arglist, complain, NULL_TREE);
4739 TREE_VEC_LENGTH (arglist)++;
4743 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4744 DECL_TEMPLATE_INSTANTIATIONS (template)
4745 = tree_cons (arglist, t,
4746 DECL_TEMPLATE_INSTANTIATIONS (template));
4748 if (TREE_CODE (t) == ENUMERAL_TYPE
4749 && !is_partial_instantiation)
4750 /* Now that the type has been registered on the instantiations
4751 list, we set up the enumerators. Because the enumeration
4752 constants may involve the enumeration type itself, we make
4753 sure to register the type first, and then create the
4754 constants. That way, doing tsubst_expr for the enumeration
4755 constants won't result in recursive calls here; we'll find
4756 the instantiation and exit above. */
4757 tsubst_enum (template_type, t, arglist);
4759 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4761 if (TREE_CODE (t) != ENUMERAL_TYPE)
4762 DECL_NAME (type_decl) = classtype_mangled_name (t);
4763 if (is_partial_instantiation)
4764 /* If the type makes use of template parameters, the
4765 code that generates debugging information will crash. */
4766 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4768 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4770 timevar_pop (TV_NAME_LOOKUP);
4777 struct pointer_set_t *visited;
4780 /* Called from for_each_template_parm via walk_tree. */
4783 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4786 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4787 tree_fn_t fn = pfd->fn;
4788 void *data = pfd->data;
4791 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4792 return error_mark_node;
4794 switch (TREE_CODE (t))
4797 if (TYPE_PTRMEMFUNC_P (t))
4803 if (!TYPE_TEMPLATE_INFO (t))
4805 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4806 fn, data, pfd->visited))
4807 return error_mark_node;
4811 /* Since we're not going to walk subtrees, we have to do this
4813 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4815 return error_mark_node;
4819 /* Check the return type. */
4820 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4821 return error_mark_node;
4823 /* Check the parameter types. Since default arguments are not
4824 instantiated until they are needed, the TYPE_ARG_TYPES may
4825 contain expressions that involve template parameters. But,
4826 no-one should be looking at them yet. And, once they're
4827 instantiated, they don't contain template parameters, so
4828 there's no point in looking at them then, either. */
4832 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4833 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4835 return error_mark_node;
4837 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4838 want walk_tree walking into them itself. */
4844 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4846 return error_mark_node;
4851 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4852 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4854 return error_mark_node;
4859 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4860 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4862 return error_mark_node;
4863 if (DECL_CONTEXT (t)
4864 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4866 return error_mark_node;
4869 case BOUND_TEMPLATE_TEMPLATE_PARM:
4870 /* Record template parameters such as `T' inside `TT<T>'. */
4871 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4872 return error_mark_node;
4875 case TEMPLATE_TEMPLATE_PARM:
4876 case TEMPLATE_TYPE_PARM:
4877 case TEMPLATE_PARM_INDEX:
4878 if (fn && (*fn)(t, data))
4879 return error_mark_node;
4881 return error_mark_node;
4885 /* A template template parameter is encountered. */
4886 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4887 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4888 return error_mark_node;
4890 /* Already substituted template template parameter */
4896 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4897 data, pfd->visited))
4898 return error_mark_node;
4902 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4903 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4904 (TREE_TYPE (t)), fn, data,
4906 return error_mark_node;
4911 /* If there's no type, then this thing must be some expression
4912 involving template parameters. */
4913 if (!fn && !TREE_TYPE (t))
4914 return error_mark_node;
4919 case REINTERPRET_CAST_EXPR:
4920 case CONST_CAST_EXPR:
4921 case STATIC_CAST_EXPR:
4922 case DYNAMIC_CAST_EXPR:
4926 case PSEUDO_DTOR_EXPR:
4928 return error_mark_node;
4932 /* If we do not handle this case specially, we end up walking
4933 the BINFO hierarchy, which is circular, and therefore
4934 confuses walk_tree. */
4936 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4938 return error_mark_node;
4945 /* We didn't find any template parameters we liked. */
4949 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4950 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4951 call FN with the parameter and the DATA.
4952 If FN returns nonzero, the iteration is terminated, and
4953 for_each_template_parm returns 1. Otherwise, the iteration
4954 continues. If FN never returns a nonzero value, the value
4955 returned by for_each_template_parm is 0. If FN is NULL, it is
4956 considered to be the function which always returns 1. */
4959 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4960 struct pointer_set_t *visited)
4962 struct pair_fn_data pfd;
4969 /* Walk the tree. (Conceptually, we would like to walk without
4970 duplicates, but for_each_template_parm_r recursively calls
4971 for_each_template_parm, so we would need to reorganize a fair
4972 bit to use walk_tree_without_duplicates, so we keep our own
4975 pfd.visited = visited;
4977 pfd.visited = pointer_set_create ();
4978 result = walk_tree (&t,
4979 for_each_template_parm_r,
4981 pfd.visited) != NULL_TREE;
4986 pointer_set_destroy (pfd.visited);
4993 /* Returns true if T depends on any template parameter. */
4996 uses_template_parms (tree t)
4999 int saved_processing_template_decl;
5001 saved_processing_template_decl = processing_template_decl;
5002 if (!saved_processing_template_decl)
5003 processing_template_decl = 1;
5005 dependent_p = dependent_type_p (t);
5006 else if (TREE_CODE (t) == TREE_VEC)
5007 dependent_p = any_dependent_template_arguments_p (t);
5008 else if (TREE_CODE (t) == TREE_LIST)
5009 dependent_p = (uses_template_parms (TREE_VALUE (t))
5010 || uses_template_parms (TREE_CHAIN (t)));
5011 else if (TREE_CODE (t) == TYPE_DECL)
5012 dependent_p = dependent_type_p (TREE_TYPE (t));
5015 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
5016 || TREE_CODE (t) == OVERLOAD
5017 || TREE_CODE (t) == BASELINK
5018 || TREE_CODE (t) == IDENTIFIER_NODE
5019 || CONSTANT_CLASS_P (t))
5020 dependent_p = (type_dependent_expression_p (t)
5021 || value_dependent_expression_p (t));
5024 gcc_assert (t == error_mark_node);
5025 dependent_p = false;
5028 processing_template_decl = saved_processing_template_decl;
5033 /* Returns true if T depends on any template parameter with level LEVEL. */
5036 uses_template_parms_level (tree t, int level)
5038 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5041 static int tinst_depth;
5042 extern int max_tinst_depth;
5043 #ifdef GATHER_STATISTICS
5046 static int tinst_level_tick;
5047 static int last_template_error_tick;
5049 /* We're starting to instantiate D; record the template instantiation context
5050 for diagnostics and to restore it later. */
5053 push_tinst_level (tree d)
5057 if (tinst_depth >= max_tinst_depth)
5059 /* If the instantiation in question still has unbound template parms,
5060 we don't really care if we can't instantiate it, so just return.
5061 This happens with base instantiation for implicit `typename'. */
5062 if (uses_template_parms (d))
5065 last_template_error_tick = tinst_level_tick;
5066 error ("template instantiation depth exceeds maximum of %d (use "
5067 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5068 max_tinst_depth, d);
5070 print_instantiation_context ();
5075 new = make_node (TINST_LEVEL);
5076 TINST_DECL (new) = d;
5077 TINST_LOCATION (new) = input_location;
5078 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5079 TREE_CHAIN (new) = current_tinst_level;
5080 current_tinst_level = new;
5083 #ifdef GATHER_STATISTICS
5084 if (tinst_depth > depth_reached)
5085 depth_reached = tinst_depth;
5092 /* We're done instantiating this template; return to the instantiation
5096 pop_tinst_level (void)
5098 tree old = current_tinst_level;
5100 /* Restore the filename and line number stashed away when we started
5101 this instantiation. */
5102 input_location = TINST_LOCATION (old);
5103 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5104 current_tinst_level = TREE_CHAIN (old);
5109 /* We're instantiating a deferred template; restore the template
5110 instantiation context in which the instantiation was requested, which
5111 is one step out from LEVEL. */
5114 reopen_tinst_level (tree level)
5119 for (t = level; t; t = TREE_CHAIN (t))
5122 current_tinst_level = level;
5126 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5127 vector of template arguments, as for tsubst.
5129 Returns an appropriate tsubst'd friend declaration. */
5132 tsubst_friend_function (tree decl, tree args)
5136 if (TREE_CODE (decl) == FUNCTION_DECL
5137 && DECL_TEMPLATE_INSTANTIATION (decl)
5138 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5139 /* This was a friend declared with an explicit template
5140 argument list, e.g.:
5144 to indicate that f was a template instantiation, not a new
5145 function declaration. Now, we have to figure out what
5146 instantiation of what template. */
5148 tree template_id, arglist, fns;
5151 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5153 /* Friend functions are looked up in the containing namespace scope.
5154 We must enter that scope, to avoid finding member functions of the
5155 current cless with same name. */
5156 push_nested_namespace (ns);
5157 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5158 tf_error | tf_warning, NULL_TREE);
5159 pop_nested_namespace (ns);
5160 arglist = tsubst (DECL_TI_ARGS (decl), args,
5161 tf_error | tf_warning, NULL_TREE);
5162 template_id = lookup_template_function (fns, arglist);
5164 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5165 tmpl = determine_specialization (template_id, new_friend,
5167 /*need_member_template=*/0,
5168 TREE_VEC_LENGTH (args));
5169 return instantiate_template (tmpl, new_args, tf_error);
5172 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5174 /* The NEW_FRIEND will look like an instantiation, to the
5175 compiler, but is not an instantiation from the point of view of
5176 the language. For example, we might have had:
5178 template <class T> struct S {
5179 template <class U> friend void f(T, U);
5182 Then, in S<int>, template <class U> void f(int, U) is not an
5183 instantiation of anything. */
5184 if (new_friend == error_mark_node)
5185 return error_mark_node;
5187 DECL_USE_TEMPLATE (new_friend) = 0;
5188 if (TREE_CODE (decl) == TEMPLATE_DECL)
5190 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5191 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5192 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5195 /* The mangled name for the NEW_FRIEND is incorrect. The function
5196 is not a template instantiation and should not be mangled like
5197 one. Therefore, we forget the mangling here; we'll recompute it
5198 later if we need it. */
5199 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5201 SET_DECL_RTL (new_friend, NULL_RTX);
5202 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5205 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5208 tree new_friend_template_info;
5209 tree new_friend_result_template_info;
5211 int new_friend_is_defn;
5213 /* We must save some information from NEW_FRIEND before calling
5214 duplicate decls since that function will free NEW_FRIEND if
5216 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5217 new_friend_is_defn =
5218 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5219 (template_for_substitution (new_friend)))
5221 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5223 /* This declaration is a `primary' template. */
5224 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5226 new_friend_result_template_info
5227 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5230 new_friend_result_template_info = NULL_TREE;
5232 /* Inside pushdecl_namespace_level, we will push into the
5233 current namespace. However, the friend function should go
5234 into the namespace of the template. */
5235 ns = decl_namespace_context (new_friend);
5236 push_nested_namespace (ns);
5237 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5238 pop_nested_namespace (ns);
5240 if (old_decl != new_friend)
5242 /* This new friend declaration matched an existing
5243 declaration. For example, given:
5245 template <class T> void f(T);
5246 template <class U> class C {
5247 template <class T> friend void f(T) {}
5250 the friend declaration actually provides the definition
5251 of `f', once C has been instantiated for some type. So,
5252 old_decl will be the out-of-class template declaration,
5253 while new_friend is the in-class definition.
5255 But, if `f' was called before this point, the
5256 instantiation of `f' will have DECL_TI_ARGS corresponding
5257 to `T' but not to `U', references to which might appear
5258 in the definition of `f'. Previously, the most general
5259 template for an instantiation of `f' was the out-of-class
5260 version; now it is the in-class version. Therefore, we
5261 run through all specialization of `f', adding to their
5262 DECL_TI_ARGS appropriately. In particular, they need a
5263 new set of outer arguments, corresponding to the
5264 arguments for this class instantiation.
5266 The same situation can arise with something like this:
5269 template <class T> class C {
5273 when `C<int>' is instantiated. Now, `f(int)' is defined
5276 if (!new_friend_is_defn)
5277 /* On the other hand, if the in-class declaration does
5278 *not* provide a definition, then we don't want to alter
5279 existing definitions. We can just leave everything
5284 /* Overwrite whatever template info was there before, if
5285 any, with the new template information pertaining to
5287 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5289 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5290 reregister_specialization (new_friend,
5291 most_general_template (old_decl),
5296 tree new_friend_args;
5298 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5299 = new_friend_result_template_info;
5301 new_friend_args = TI_ARGS (new_friend_template_info);
5302 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5306 tree spec = TREE_VALUE (t);
5309 = add_outermost_template_args (new_friend_args,
5310 DECL_TI_ARGS (spec));
5313 /* Now, since specializations are always supposed to
5314 hang off of the most general template, we must move
5316 t = most_general_template (old_decl);
5319 DECL_TEMPLATE_SPECIALIZATIONS (t)
5320 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5321 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5322 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5327 /* The information from NEW_FRIEND has been merged into OLD_DECL
5328 by duplicate_decls. */
5329 new_friend = old_decl;
5334 tree context = DECL_CONTEXT (new_friend);
5338 template <class T> class C {
5339 template <class U> friend void C1<U>::f (); // case 1
5340 friend void C2<T>::f (); // case 2
5342 we only need to make sure CONTEXT is a complete type for
5343 case 2. To distinguish between the two cases, we note that
5344 CONTEXT of case 1 remains dependent type after tsubst while
5345 this isn't true for case 2. */
5346 ++processing_template_decl;
5347 dependent_p = dependent_type_p (context);
5348 --processing_template_decl;
5351 && !complete_type_or_else (context, NULL_TREE))
5352 return error_mark_node;
5354 if (COMPLETE_TYPE_P (context))
5356 /* Check to see that the declaration is really present, and,
5357 possibly obtain an improved declaration. */
5358 tree fn = check_classfn (context,
5359 new_friend, NULL_TREE);
5369 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5370 template arguments, as for tsubst.
5372 Returns an appropriate tsubst'd friend type or error_mark_node on
5376 tsubst_friend_class (tree friend_tmpl, tree args)
5382 context = DECL_CONTEXT (friend_tmpl);
5386 if (TREE_CODE (context) == NAMESPACE_DECL)
5387 push_nested_namespace (context);
5389 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5392 /* First, we look for a class template. */
5393 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5395 /* But, if we don't find one, it might be because we're in a
5396 situation like this:
5404 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5405 for `S<int>', not the TEMPLATE_DECL. */
5406 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5408 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5409 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5412 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5414 /* The friend template has already been declared. Just
5415 check to see that the declarations match, and install any new
5416 default parameters. We must tsubst the default parameters,
5417 of course. We only need the innermost template parameters
5418 because that is all that redeclare_class_template will look
5420 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5421 > TMPL_ARGS_DEPTH (args))
5424 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5425 args, tf_error | tf_warning);
5426 redeclare_class_template (TREE_TYPE (tmpl), parms);
5429 friend_type = TREE_TYPE (tmpl);
5433 /* The friend template has not already been declared. In this
5434 case, the instantiation of the template class will cause the
5435 injection of this template into the global scope. */
5436 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5438 /* The new TMPL is not an instantiation of anything, so we
5439 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5440 the new type because that is supposed to be the corresponding
5441 template decl, i.e., TMPL. */
5442 DECL_USE_TEMPLATE (tmpl) = 0;
5443 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5444 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5445 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5446 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5448 /* Inject this template into the global scope. */
5449 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5454 if (TREE_CODE (context) == NAMESPACE_DECL)
5455 pop_nested_namespace (context);
5457 pop_nested_class ();
5463 /* Returns zero if TYPE cannot be completed later due to circularity.
5464 Otherwise returns one. */
5467 can_complete_type_without_circularity (tree type)
5469 if (type == NULL_TREE || type == error_mark_node)
5471 else if (COMPLETE_TYPE_P (type))
5473 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5474 return can_complete_type_without_circularity (TREE_TYPE (type));
5475 else if (CLASS_TYPE_P (type)
5476 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5483 instantiate_class_template (tree type)
5485 tree template, args, pattern, t, member;
5490 if (type == error_mark_node)
5491 return error_mark_node;
5493 if (TYPE_BEING_DEFINED (type)
5494 || COMPLETE_TYPE_P (type)
5495 || dependent_type_p (type))
5498 /* Figure out which template is being instantiated. */
5499 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5500 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5502 /* Determine what specialization of the original template to
5504 t = most_specialized_class (type, template);
5505 if (t == error_mark_node)
5507 TYPE_BEING_DEFINED (type) = 1;
5508 return error_mark_node;
5512 /* This TYPE is actually an instantiation of a partial
5513 specialization. We replace the innermost set of ARGS with
5514 the arguments appropriate for substitution. For example,
5517 template <class T> struct S {};
5518 template <class T> struct S<T*> {};
5520 and supposing that we are instantiating S<int*>, ARGS will
5521 presently be {int*} -- but we need {int}. */
5522 pattern = TREE_TYPE (t);
5523 args = TREE_PURPOSE (t);
5527 pattern = TREE_TYPE (template);
5528 args = CLASSTYPE_TI_ARGS (type);
5531 /* If the template we're instantiating is incomplete, then clearly
5532 there's nothing we can do. */
5533 if (!COMPLETE_TYPE_P (pattern))
5536 /* If we've recursively instantiated too many templates, stop. */
5537 if (! push_tinst_level (type))
5540 /* Now we're really doing the instantiation. Mark the type as in
5541 the process of being defined. */
5542 TYPE_BEING_DEFINED (type) = 1;
5544 /* We may be in the middle of deferred access check. Disable
5546 push_deferring_access_checks (dk_no_deferred);
5548 push_to_top_level ();
5550 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5552 /* Set the input location to the template definition. This is needed
5553 if tsubsting causes an error. */
5554 typedecl = TYPE_MAIN_DECL (type);
5555 input_location = DECL_SOURCE_LOCATION (typedecl);
5556 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5558 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5559 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5560 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5561 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5562 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5563 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5564 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5565 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5566 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5567 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5568 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5569 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5570 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5571 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5572 if (ANON_AGGR_TYPE_P (pattern))
5573 SET_ANON_AGGR_TYPE_P (type);
5574 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5576 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5577 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5580 pbinfo = TYPE_BINFO (pattern);
5582 /* We should never instantiate a nested class before its enclosing
5583 class; we need to look up the nested class by name before we can
5584 instantiate it, and that lookup should instantiate the enclosing
5586 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5587 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5588 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5590 base_list = NULL_TREE;
5591 if (BINFO_N_BASE_BINFOS (pbinfo))
5594 tree context = TYPE_CONTEXT (type);
5598 /* We must enter the scope containing the type, as that is where
5599 the accessibility of types named in dependent bases are
5601 pushed_scope = push_scope (context ? context : global_namespace);
5603 /* Substitute into each of the bases to determine the actual
5605 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5608 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5610 /* Substitute to figure out the base class. */
5611 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5612 if (base == error_mark_node)
5615 base_list = tree_cons (access, base, base_list);
5616 if (BINFO_VIRTUAL_P (pbase_binfo))
5617 TREE_TYPE (base_list) = integer_type_node;
5620 /* The list is now in reverse order; correct that. */
5621 base_list = nreverse (base_list);
5624 pop_scope (pushed_scope);
5626 /* Now call xref_basetypes to set up all the base-class
5628 xref_basetypes (type, base_list);
5631 /* Now that our base classes are set up, enter the scope of the
5632 class, so that name lookups into base classes, etc. will work
5633 correctly. This is precisely analogous to what we do in
5634 begin_class_definition when defining an ordinary non-template
5638 /* Now members are processed in the order of declaration. */
5639 for (member = CLASSTYPE_DECL_LIST (pattern);
5640 member; member = TREE_CHAIN (member))
5642 tree t = TREE_VALUE (member);
5644 if (TREE_PURPOSE (member))
5648 /* Build new CLASSTYPE_NESTED_UTDS. */
5651 tree name = TYPE_IDENTIFIER (tag);
5653 bool class_template_p;
5655 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5656 && TYPE_LANG_SPECIFIC (tag)
5657 && CLASSTYPE_IS_TEMPLATE (tag));
5658 /* If the member is a class template, then -- even after
5659 substitution -- there may be dependent types in the
5660 template argument list for the class. We increment
5661 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5662 that function will assume that no types are dependent
5663 when outside of a template. */
5664 if (class_template_p)
5665 ++processing_template_decl;
5666 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5667 if (class_template_p)
5668 --processing_template_decl;
5669 if (newtag == error_mark_node)
5672 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5674 if (class_template_p)
5675 /* Unfortunately, lookup_template_class sets
5676 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5677 instantiation (i.e., for the type of a member
5678 template class nested within a template class.)
5679 This behavior is required for
5680 maybe_process_partial_specialization to work
5681 correctly, but is not accurate in this case;
5682 the TAG is not an instantiation of anything.
5683 (The corresponding TEMPLATE_DECL is an
5684 instantiation, but the TYPE is not.) */
5685 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5687 /* Now, we call pushtag to put this NEWTAG into the scope of
5688 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5689 pushtag calling push_template_decl. We don't have to do
5690 this for enums because it will already have been done in
5693 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5694 pushtag (name, newtag, /*tag_scope=*/ts_current);
5697 else if (TREE_CODE (t) == FUNCTION_DECL
5698 || DECL_FUNCTION_TEMPLATE_P (t))
5700 /* Build new TYPE_METHODS. */
5703 if (TREE_CODE (t) == TEMPLATE_DECL)
5704 ++processing_template_decl;
5705 r = tsubst (t, args, tf_error, NULL_TREE);
5706 if (TREE_CODE (t) == TEMPLATE_DECL)
5707 --processing_template_decl;
5708 set_current_access_from_decl (r);
5709 grok_special_member_properties (r);
5710 finish_member_declaration (r);
5714 /* Build new TYPE_FIELDS. */
5716 if (TREE_CODE (t) != CONST_DECL)
5720 /* The the file and line for this declaration, to
5721 assist in error message reporting. Since we
5722 called push_tinst_level above, we don't need to
5724 input_location = DECL_SOURCE_LOCATION (t);
5726 if (TREE_CODE (t) == TEMPLATE_DECL)
5727 ++processing_template_decl;
5728 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5729 if (TREE_CODE (t) == TEMPLATE_DECL)
5730 --processing_template_decl;
5731 if (TREE_CODE (r) == VAR_DECL)
5735 [t]he initialization (and any associated
5736 side-effects) of a static data member does
5737 not occur unless the static data member is
5738 itself used in a way that requires the
5739 definition of the static data member to
5742 Therefore, we do not substitute into the
5743 initialized for the static data member here. */
5744 finish_static_data_member_decl
5747 /*init_const_expr_p=*/false,
5748 /*asmspec_tree=*/NULL_TREE,
5750 if (DECL_INITIALIZED_IN_CLASS_P (r))
5751 check_static_variable_definition (r, TREE_TYPE (r));
5753 else if (TREE_CODE (r) == FIELD_DECL)
5755 /* Determine whether R has a valid type and can be
5756 completed later. If R is invalid, then it is
5757 replaced by error_mark_node so that it will not be
5758 added to TYPE_FIELDS. */
5759 tree rtype = TREE_TYPE (r);
5760 if (can_complete_type_without_circularity (rtype))
5761 complete_type (rtype);
5763 if (!COMPLETE_TYPE_P (rtype))
5765 cxx_incomplete_type_error (r, rtype);
5766 r = error_mark_node;
5770 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5771 such a thing will already have been added to the field
5772 list by tsubst_enum in finish_member_declaration in the
5773 CLASSTYPE_NESTED_UTDS case above. */
5774 if (!(TREE_CODE (r) == TYPE_DECL
5775 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5776 && DECL_ARTIFICIAL (r)))
5778 set_current_access_from_decl (r);
5779 finish_member_declaration (r);
5786 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5788 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5790 tree friend_type = t;
5791 bool adjust_processing_template_decl = false;
5793 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5795 /* template <class T> friend class C; */
5796 friend_type = tsubst_friend_class (friend_type, args);
5797 adjust_processing_template_decl = true;
5799 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5801 /* template <class T> friend class C::D; */
5802 friend_type = tsubst (friend_type, args,
5803 tf_error | tf_warning, NULL_TREE);
5804 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5805 friend_type = TREE_TYPE (friend_type);
5806 adjust_processing_template_decl = true;
5808 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5810 /* This could be either
5814 when dependent_type_p is false or
5816 template <class U> friend class T::C;
5819 friend_type = tsubst (friend_type, args,
5820 tf_error | tf_warning, NULL_TREE);
5821 /* Bump processing_template_decl for correct
5822 dependent_type_p calculation. */
5823 ++processing_template_decl;
5824 if (dependent_type_p (friend_type))
5825 adjust_processing_template_decl = true;
5826 --processing_template_decl;
5828 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5829 && hidden_name_p (TYPE_NAME (friend_type)))
5833 where C hasn't been declared yet. Let's lookup name
5834 from namespace scope directly, bypassing any name that
5835 come from dependent base class. */
5836 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5838 /* The call to xref_tag_from_type does injection for friend
5840 push_nested_namespace (ns);
5842 xref_tag_from_type (friend_type, NULL_TREE,
5843 /*tag_scope=*/ts_current);
5844 pop_nested_namespace (ns);
5846 else if (uses_template_parms (friend_type))
5847 /* friend class C<T>; */
5848 friend_type = tsubst (friend_type, args,
5849 tf_error | tf_warning, NULL_TREE);
5854 where C is already declared or
5856 friend class C<int>;
5858 We don't have to do anything in these cases. */
5860 if (adjust_processing_template_decl)
5861 /* Trick make_friend_class into realizing that the friend
5862 we're adding is a template, not an ordinary class. It's
5863 important that we use make_friend_class since it will
5864 perform some error-checking and output cross-reference
5866 ++processing_template_decl;
5868 if (friend_type != error_mark_node)
5869 make_friend_class (type, friend_type, /*complain=*/false);
5871 if (adjust_processing_template_decl)
5872 --processing_template_decl;
5876 /* Build new DECL_FRIENDLIST. */
5879 /* The the file and line for this declaration, to
5880 assist in error message reporting. Since we
5881 called push_tinst_level above, we don't need to
5883 input_location = DECL_SOURCE_LOCATION (t);
5885 if (TREE_CODE (t) == TEMPLATE_DECL)
5887 ++processing_template_decl;
5888 push_deferring_access_checks (dk_no_check);
5891 r = tsubst_friend_function (t, args);
5892 add_friend (type, r, /*complain=*/false);
5893 if (TREE_CODE (t) == TEMPLATE_DECL)
5895 pop_deferring_access_checks ();
5896 --processing_template_decl;
5902 /* Set the file and line number information to whatever is given for
5903 the class itself. This puts error messages involving generated
5904 implicit functions at a predictable point, and the same point
5905 that would be used for non-template classes. */
5906 input_location = DECL_SOURCE_LOCATION (typedecl);
5908 unreverse_member_declarations (type);
5909 finish_struct_1 (type);
5910 TYPE_BEING_DEFINED (type) = 0;
5912 /* Now that the class is complete, instantiate default arguments for
5913 any member functions. We don't do this earlier because the
5914 default arguments may reference members of the class. */
5915 if (!PRIMARY_TEMPLATE_P (template))
5916 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5917 if (TREE_CODE (t) == FUNCTION_DECL
5918 /* Implicitly generated member functions will not have template
5919 information; they are not instantiations, but instead are
5920 created "fresh" for each instantiation. */
5921 && DECL_TEMPLATE_INFO (t))
5922 tsubst_default_arguments (t);
5925 pop_from_top_level ();
5926 pop_deferring_access_checks ();
5929 /* The vtable for a template class can be emitted in any translation
5930 unit in which the class is instantiated. When there is no key
5931 method, however, finish_struct_1 will already have added TYPE to
5932 the keyed_classes list. */
5933 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5934 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5940 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5946 else if (TYPE_P (t))
5947 r = tsubst (t, args, complain, in_decl);
5950 r = tsubst_expr (t, args, complain, in_decl);
5951 r = fold_non_dependent_expr (r);
5956 /* Substitute ARGS into the vector or list of template arguments T. */
5959 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5961 int len = TREE_VEC_LENGTH (t);
5962 int need_new = 0, i;
5963 tree *elts = alloca (len * sizeof (tree));
5965 for (i = 0; i < len; i++)
5967 tree orig_arg = TREE_VEC_ELT (t, i);
5970 if (TREE_CODE (orig_arg) == TREE_VEC)
5971 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5973 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5975 if (new_arg == error_mark_node)
5976 return error_mark_node;
5979 if (new_arg != orig_arg)
5986 t = make_tree_vec (len);
5987 for (i = 0; i < len; i++)
5988 TREE_VEC_ELT (t, i) = elts[i];
5993 /* Return the result of substituting ARGS into the template parameters
5994 given by PARMS. If there are m levels of ARGS and m + n levels of
5995 PARMS, then the result will contain n levels of PARMS. For
5996 example, if PARMS is `template <class T> template <class U>
5997 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5998 result will be `template <int*, double, class V>'. */
6001 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6006 /* When substituting into a template, we must set
6007 PROCESSING_TEMPLATE_DECL as the template parameters may be
6008 dependent if they are based on one-another, and the dependency
6009 predicates are short-circuit outside of templates. */
6010 ++processing_template_decl;
6012 for (new_parms = &r;
6013 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6014 new_parms = &(TREE_CHAIN (*new_parms)),
6015 parms = TREE_CHAIN (parms))
6018 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6021 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6023 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6024 tree default_value = TREE_PURPOSE (tuple);
6025 tree parm_decl = TREE_VALUE (tuple);
6027 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6028 if (TREE_CODE (parm_decl) == PARM_DECL
6029 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6030 parm_decl = error_mark_node;
6031 default_value = tsubst_template_arg (default_value, args,
6032 complain, NULL_TREE);
6034 tuple = build_tree_list (default_value, parm_decl);
6035 TREE_VEC_ELT (new_vec, i) = tuple;
6039 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6040 - TMPL_ARGS_DEPTH (args)),
6041 new_vec, NULL_TREE);
6044 --processing_template_decl;
6049 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6050 type T. If T is not an aggregate or enumeration type, it is
6051 handled as if by tsubst. IN_DECL is as for tsubst. If
6052 ENTERING_SCOPE is nonzero, T is the context for a template which
6053 we are presently tsubst'ing. Return the substituted value. */
6056 tsubst_aggr_type (tree t,
6058 tsubst_flags_t complain,
6065 switch (TREE_CODE (t))
6068 if (TYPE_PTRMEMFUNC_P (t))
6069 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6071 /* Else fall through. */
6074 if (TYPE_TEMPLATE_INFO (t))
6079 bool saved_skip_evaluation;
6081 /* In "sizeof(X<I>)" we need to evaluate "I". */
6082 saved_skip_evaluation = skip_evaluation;
6083 skip_evaluation = false;
6085 /* First, determine the context for the type we are looking
6087 context = TYPE_CONTEXT (t);
6089 context = tsubst_aggr_type (context, args, complain,
6090 in_decl, /*entering_scope=*/1);
6092 /* Then, figure out what arguments are appropriate for the
6093 type we are trying to find. For example, given:
6095 template <class T> struct S;
6096 template <class T, class U> void f(T, U) { S<U> su; }
6098 and supposing that we are instantiating f<int, double>,
6099 then our ARGS will be {int, double}, but, when looking up
6100 S we only want {double}. */
6101 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6103 if (argvec == error_mark_node)
6104 r = error_mark_node;
6107 r = lookup_template_class (t, argvec, in_decl, context,
6108 entering_scope, complain);
6109 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6112 skip_evaluation = saved_skip_evaluation;
6117 /* This is not a template type, so there's nothing to do. */
6121 return tsubst (t, args, complain, in_decl);
6125 /* Substitute into the default argument ARG (a default argument for
6126 FN), which has the indicated TYPE. */
6129 tsubst_default_argument (tree fn, tree type, tree arg)
6131 tree saved_class_ptr = NULL_TREE;
6132 tree saved_class_ref = NULL_TREE;
6134 /* This default argument came from a template. Instantiate the
6135 default argument here, not in tsubst. In the case of
6144 we must be careful to do name lookup in the scope of S<T>,
6145 rather than in the current class. */
6146 push_access_scope (fn);
6147 /* The "this" pointer is not valid in a default argument. */
6150 saved_class_ptr = current_class_ptr;
6151 cp_function_chain->x_current_class_ptr = NULL_TREE;
6152 saved_class_ref = current_class_ref;
6153 cp_function_chain->x_current_class_ref = NULL_TREE;
6156 push_deferring_access_checks(dk_no_deferred);
6157 /* The default argument expression may cause implicitly defined
6158 member functions to be synthesized, which will result in garbage
6159 collection. We must treat this situation as if we were within
6160 the body of function so as to avoid collecting live data on the
6163 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6164 tf_error | tf_warning, NULL_TREE);
6166 pop_deferring_access_checks();
6168 /* Restore the "this" pointer. */
6171 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6172 cp_function_chain->x_current_class_ref = saved_class_ref;
6175 pop_access_scope (fn);
6177 /* Make sure the default argument is reasonable. */
6178 arg = check_default_argument (type, arg);
6183 /* Substitute into all the default arguments for FN. */
6186 tsubst_default_arguments (tree fn)
6191 tmpl_args = DECL_TI_ARGS (fn);
6193 /* If this function is not yet instantiated, we certainly don't need
6194 its default arguments. */
6195 if (uses_template_parms (tmpl_args))
6198 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6200 arg = TREE_CHAIN (arg))
6201 if (TREE_PURPOSE (arg))
6202 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6204 TREE_PURPOSE (arg));
6207 /* Substitute the ARGS into the T, which is a _DECL. Return the
6208 result of the substitution. Issue error and warning messages under
6209 control of COMPLAIN. */
6212 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6214 location_t saved_loc;
6218 /* Set the filename and linenumber to improve error-reporting. */
6219 saved_loc = input_location;
6220 input_location = DECL_SOURCE_LOCATION (t);
6222 switch (TREE_CODE (t))
6226 /* We can get here when processing a member function template,
6227 member class template, and template template parameter of
6228 a template class. */
6229 tree decl = DECL_TEMPLATE_RESULT (t);
6234 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6236 /* Template template parameter is treated here. */
6237 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6238 if (new_type == error_mark_node)
6239 return error_mark_node;
6242 TREE_CHAIN (r) = NULL_TREE;
6243 TREE_TYPE (r) = new_type;
6244 DECL_TEMPLATE_RESULT (r)
6245 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6246 DECL_TEMPLATE_PARMS (r)
6247 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6249 TYPE_NAME (new_type) = r;
6253 /* We might already have an instance of this template.
6254 The ARGS are for the surrounding class type, so the
6255 full args contain the tsubst'd args for the context,
6256 plus the innermost args from the template decl. */
6257 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6258 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6259 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6260 /* Because this is a template, the arguments will still be
6261 dependent, even after substitution. If
6262 PROCESSING_TEMPLATE_DECL is not set, the dependency
6263 predicates will short-circuit. */
6264 ++processing_template_decl;
6265 full_args = tsubst_template_args (tmpl_args, args,
6267 --processing_template_decl;
6268 if (full_args == error_mark_node)
6269 return error_mark_node;
6271 /* tsubst_template_args doesn't copy the vector if
6272 nothing changed. But, *something* should have
6274 gcc_assert (full_args != tmpl_args);
6276 spec = retrieve_specialization (t, full_args,
6277 /*class_specializations_p=*/true);
6278 if (spec != NULL_TREE)
6284 /* Make a new template decl. It will be similar to the
6285 original, but will record the current template arguments.
6286 We also create a new function declaration, which is just
6287 like the old one, but points to this new template, rather
6288 than the old one. */
6290 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6291 TREE_CHAIN (r) = NULL_TREE;
6293 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6295 if (TREE_CODE (decl) == TYPE_DECL)
6298 ++processing_template_decl;
6299 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6300 --processing_template_decl;
6301 if (new_type == error_mark_node)
6302 return error_mark_node;
6304 TREE_TYPE (r) = new_type;
6305 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6306 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6307 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6308 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6313 ++processing_template_decl;
6314 new_decl = tsubst (decl, args, complain, in_decl);
6315 --processing_template_decl;
6316 if (new_decl == error_mark_node)
6317 return error_mark_node;
6319 DECL_TEMPLATE_RESULT (r) = new_decl;
6320 DECL_TI_TEMPLATE (new_decl) = r;
6321 TREE_TYPE (r) = TREE_TYPE (new_decl);
6322 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6323 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6326 SET_DECL_IMPLICIT_INSTANTIATION (r);
6327 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6328 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6330 /* The template parameters for this new template are all the
6331 template parameters for the old template, except the
6332 outermost level of parameters. */
6333 DECL_TEMPLATE_PARMS (r)
6334 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6337 if (PRIMARY_TEMPLATE_P (t))
6338 DECL_PRIMARY_TEMPLATE (r) = r;
6340 if (TREE_CODE (decl) != TYPE_DECL)
6341 /* Record this non-type partial instantiation. */
6342 register_specialization (r, t,
6343 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6351 tree argvec = NULL_TREE;
6359 /* Nobody should be tsubst'ing into non-template functions. */
6360 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6362 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6367 /* If T is not dependent, just return it. We have to
6368 increment PROCESSING_TEMPLATE_DECL because
6369 value_dependent_expression_p assumes that nothing is
6370 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6371 ++processing_template_decl;
6372 dependent_p = value_dependent_expression_p (t);
6373 --processing_template_decl;
6377 /* Calculate the most general template of which R is a
6378 specialization, and the complete set of arguments used to
6380 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6381 argvec = tsubst_template_args (DECL_TI_ARGS
6382 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6383 args, complain, in_decl);
6385 /* Check to see if we already have this specialization. */
6386 spec = retrieve_specialization (gen_tmpl, argvec,
6387 /*class_specializations_p=*/false);
6395 /* We can see more levels of arguments than parameters if
6396 there was a specialization of a member template, like
6399 template <class T> struct S { template <class U> void f(); }
6400 template <> template <class U> void S<int>::f(U);
6402 Here, we'll be substituting into the specialization,
6403 because that's where we can find the code we actually
6404 want to generate, but we'll have enough arguments for
6405 the most general template.
6407 We also deal with the peculiar case:
6409 template <class T> struct S {
6410 template <class U> friend void f();
6412 template <class U> void f() {}
6414 template void f<double>();
6416 Here, the ARGS for the instantiation of will be {int,
6417 double}. But, we only need as many ARGS as there are
6418 levels of template parameters in CODE_PATTERN. We are
6419 careful not to get fooled into reducing the ARGS in
6422 template <class T> struct S { template <class U> void f(U); }
6423 template <class T> template <> void S<T>::f(int) {}
6425 which we can spot because the pattern will be a
6426 specialization in this case. */
6427 args_depth = TMPL_ARGS_DEPTH (args);
6429 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6430 if (args_depth > parms_depth
6431 && !DECL_TEMPLATE_SPECIALIZATION (t))
6432 args = get_innermost_template_args (args, parms_depth);
6436 /* This special case arises when we have something like this:
6438 template <class T> struct S {
6439 friend void f<int>(int, double);
6442 Here, the DECL_TI_TEMPLATE for the friend declaration
6443 will be an IDENTIFIER_NODE. We are being called from
6444 tsubst_friend_function, and we want only to create a
6445 new decl (R) with appropriate types so that we can call
6446 determine_specialization. */
6447 gen_tmpl = NULL_TREE;
6450 if (DECL_CLASS_SCOPE_P (t))
6452 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6456 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6457 complain, t, /*entering_scope=*/1);
6462 ctx = DECL_CONTEXT (t);
6464 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6465 if (type == error_mark_node)
6466 return error_mark_node;
6468 /* We do NOT check for matching decls pushed separately at this
6469 point, as they may not represent instantiations of this
6470 template, and in any case are considered separate under the
6473 DECL_USE_TEMPLATE (r) = 0;
6474 TREE_TYPE (r) = type;
6475 /* Clear out the mangled name and RTL for the instantiation. */
6476 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6477 SET_DECL_RTL (r, NULL_RTX);
6478 DECL_INITIAL (r) = NULL_TREE;
6479 DECL_CONTEXT (r) = ctx;
6481 if (member && DECL_CONV_FN_P (r))
6482 /* Type-conversion operator. Reconstruct the name, in
6483 case it's the name of one of the template's parameters. */
6484 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6486 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6488 DECL_RESULT (r) = NULL_TREE;
6490 TREE_STATIC (r) = 0;
6491 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6492 DECL_EXTERNAL (r) = 1;
6493 /* If this is an instantiation of a function with internal
6494 linkage, we already know what object file linkage will be
6495 assigned to the instantiation. */
6496 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6497 DECL_DEFER_OUTPUT (r) = 0;
6498 TREE_CHAIN (r) = NULL_TREE;
6499 DECL_PENDING_INLINE_INFO (r) = 0;
6500 DECL_PENDING_INLINE_P (r) = 0;
6501 DECL_SAVED_TREE (r) = NULL_TREE;
6503 if (DECL_CLONED_FUNCTION (r))
6505 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6507 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6508 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6511 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6512 this in the special friend case mentioned above where
6513 GEN_TMPL is NULL. */
6516 DECL_TEMPLATE_INFO (r)
6517 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6518 SET_DECL_IMPLICIT_INSTANTIATION (r);
6519 register_specialization (r, gen_tmpl, argvec, false);
6521 /* We're not supposed to instantiate default arguments
6522 until they are called, for a template. But, for a
6525 template <class T> void f ()
6526 { extern void g(int i = T()); }
6528 we should do the substitution when the template is
6529 instantiated. We handle the member function case in
6530 instantiate_class_template since the default arguments
6531 might refer to other members of the class. */
6533 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6534 && !uses_template_parms (argvec))
6535 tsubst_default_arguments (r);
6538 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6540 /* Copy the list of befriending classes. */
6541 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6543 friends = &TREE_CHAIN (*friends))
6545 *friends = copy_node (*friends);
6546 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6551 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6553 maybe_retrofit_in_chrg (r);
6554 if (DECL_CONSTRUCTOR_P (r))
6555 grok_ctor_properties (ctx, r);
6556 /* If this is an instantiation of a member template, clone it.
6557 If it isn't, that'll be handled by
6558 clone_constructors_and_destructors. */
6559 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6560 clone_function_decl (r, /*update_method_vec_p=*/0);
6562 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6563 grok_op_properties (r, (complain & tf_error) != 0);
6565 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6566 SET_DECL_FRIEND_CONTEXT (r,
6567 tsubst (DECL_FRIEND_CONTEXT (t),
6568 args, complain, in_decl));
6577 if (DECL_TEMPLATE_PARM_P (t))
6578 SET_DECL_TEMPLATE_PARM_P (r);
6580 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6581 type = type_decays_to (type);
6582 TREE_TYPE (r) = type;
6583 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6585 if (DECL_INITIAL (r))
6587 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6588 DECL_INITIAL (r) = TREE_TYPE (r);
6590 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6594 DECL_CONTEXT (r) = NULL_TREE;
6596 if (!DECL_TEMPLATE_PARM_P (r))
6597 DECL_ARG_TYPE (r) = type_passed_as (type);
6599 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6600 complain, TREE_CHAIN (t));
6609 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6610 if (type == error_mark_node)
6611 return error_mark_node;
6612 TREE_TYPE (r) = type;
6613 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6615 /* We don't have to set DECL_CONTEXT here; it is set by
6616 finish_member_declaration. */
6617 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6619 TREE_CHAIN (r) = NULL_TREE;
6620 if (VOID_TYPE_P (type))
6621 error ("instantiation of %q+D as type %qT", r, type);
6626 /* We reach here only for member using decls. */
6627 if (DECL_DEPENDENT_P (t))
6629 r = do_class_using_decl
6630 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6631 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6633 r = error_mark_node;
6638 TREE_CHAIN (r) = NULL_TREE;
6645 tree argvec = NULL_TREE;
6646 tree gen_tmpl = NULL_TREE;
6648 tree tmpl = NULL_TREE;
6650 tree type = NULL_TREE;
6653 if (TREE_CODE (t) == TYPE_DECL)
6655 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6656 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6657 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6659 /* If this is the canonical decl, we don't have to
6660 mess with instantiations, and often we can't (for
6661 typename, template type parms and such). Note that
6662 TYPE_NAME is not correct for the above test if
6663 we've copied the type for a typedef. */
6664 r = TYPE_NAME (type);
6669 /* Assume this is a non-local variable. */
6672 if (TYPE_P (CP_DECL_CONTEXT (t)))
6673 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6675 in_decl, /*entering_scope=*/1);
6676 else if (DECL_NAMESPACE_SCOPE_P (t))
6677 ctx = DECL_CONTEXT (t);
6680 /* Subsequent calls to pushdecl will fill this in. */
6685 /* Check to see if we already have this specialization. */
6688 tmpl = DECL_TI_TEMPLATE (t);
6689 gen_tmpl = most_general_template (tmpl);
6690 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6691 spec = retrieve_specialization (gen_tmpl, argvec,
6692 /*class_specializations_p=*/false);
6695 spec = retrieve_local_specialization (t);
6704 if (TREE_CODE (r) == VAR_DECL)
6706 /* Even if the original location is out of scope, the
6707 newly substituted one is not. */
6708 DECL_DEAD_FOR_LOCAL (r) = 0;
6709 DECL_INITIALIZED_P (r) = 0;
6710 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6711 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6712 if (type == error_mark_node)
6713 return error_mark_node;
6714 type = complete_type (type);
6715 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6716 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6717 type = check_var_type (DECL_NAME (r), type);
6719 if (DECL_HAS_VALUE_EXPR_P (t))
6721 tree ve = DECL_VALUE_EXPR (t);
6722 ve = tsubst_expr (ve, args, complain, in_decl);
6723 SET_DECL_VALUE_EXPR (r, ve);
6726 else if (DECL_SELF_REFERENCE_P (t))
6727 SET_DECL_SELF_REFERENCE_P (r);
6728 TREE_TYPE (r) = type;
6729 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6730 DECL_CONTEXT (r) = ctx;
6731 /* Clear out the mangled name and RTL for the instantiation. */
6732 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6733 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6734 SET_DECL_RTL (r, NULL_RTX);
6735 /* The initializer must not be expanded until it is required;
6737 DECL_INITIAL (r) = NULL_TREE;
6738 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6739 SET_DECL_RTL (r, NULL_RTX);
6740 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6744 /* A static data member declaration is always marked
6745 external when it is declared in-class, even if an
6746 initializer is present. We mimic the non-template
6748 DECL_EXTERNAL (r) = 1;
6750 register_specialization (r, gen_tmpl, argvec, false);
6751 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6752 SET_DECL_IMPLICIT_INSTANTIATION (r);
6755 register_local_specialization (r, t);
6757 TREE_CHAIN (r) = NULL_TREE;
6766 /* Restore the file and line information. */
6767 input_location = saved_loc;
6772 /* Substitute into the ARG_TYPES of a function type. */
6775 tsubst_arg_types (tree arg_types,
6777 tsubst_flags_t complain,
6780 tree remaining_arg_types;
6783 tree result = NULL_TREE;
6785 if (!arg_types || arg_types == void_list_node)
6788 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6789 args, complain, in_decl);
6790 if (remaining_arg_types == error_mark_node)
6791 return error_mark_node;
6793 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6794 if (type == error_mark_node)
6795 return error_mark_node;
6796 if (VOID_TYPE_P (type))
6798 if (complain & tf_error)
6800 error ("invalid parameter type %qT", type);
6802 error ("in declaration %q+D", in_decl);
6804 return error_mark_node;
6807 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6808 top-level qualifiers as required. */
6809 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6811 /* We do not substitute into default arguments here. The standard
6812 mandates that they be instantiated only when needed, which is
6813 done in build_over_call. */
6814 default_arg = TREE_PURPOSE (arg_types);
6816 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6818 /* We've instantiated a template before its default arguments
6819 have been parsed. This can happen for a nested template
6820 class, and is not an error unless we require the default
6821 argument in a call of this function. */
6822 result = tree_cons (default_arg, type, remaining_arg_types);
6823 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6826 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6831 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6832 *not* handle the exception-specification for FNTYPE, because the
6833 initial substitution of explicitly provided template parameters
6834 during argument deduction forbids substitution into the
6835 exception-specification:
6839 All references in the function type of the function template to the
6840 corresponding template parameters are replaced by the specified tem-
6841 plate argument values. If a substitution in a template parameter or
6842 in the function type of the function template results in an invalid
6843 type, type deduction fails. [Note: The equivalent substitution in
6844 exception specifications is done only when the function is instanti-
6845 ated, at which point a program is ill-formed if the substitution
6846 results in an invalid type.] */
6849 tsubst_function_type (tree t,
6851 tsubst_flags_t complain,
6858 /* The TYPE_CONTEXT is not used for function/method types. */
6859 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6861 /* Substitute the return type. */
6862 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6863 if (return_type == error_mark_node)
6864 return error_mark_node;
6865 /* The standard does not presently indicate that creation of a
6866 function type with an invalid return type is a deduction failure.
6867 However, that is clearly analogous to creating an array of "void"
6868 or a reference to a reference. This is core issue #486. */
6869 if (TREE_CODE (return_type) == ARRAY_TYPE
6870 || TREE_CODE (return_type) == FUNCTION_TYPE)
6872 if (complain & tf_error)
6874 if (TREE_CODE (return_type) == ARRAY_TYPE)
6875 error ("function returning an array");
6877 error ("function returning a function");
6879 return error_mark_node;
6882 /* Substitute the argument types. */
6883 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6885 if (arg_types == error_mark_node)
6886 return error_mark_node;
6888 /* Construct a new type node and return it. */
6889 if (TREE_CODE (t) == FUNCTION_TYPE)
6890 fntype = build_function_type (return_type, arg_types);
6893 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6894 if (! IS_AGGR_TYPE (r))
6898 Type deduction may fail for any of the following
6901 -- Attempting to create "pointer to member of T" when T
6902 is not a class type. */
6903 if (complain & tf_error)
6904 error ("creating pointer to member function of non-class type %qT",
6906 return error_mark_node;
6909 fntype = build_method_type_directly (r, return_type,
6910 TREE_CHAIN (arg_types));
6912 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6913 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6918 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6919 ARGS into that specification, and return the substituted
6920 specification. If there is no specification, return NULL_TREE. */
6923 tsubst_exception_specification (tree fntype,
6925 tsubst_flags_t complain,
6931 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6932 new_specs = NULL_TREE;
6935 if (! TREE_VALUE (specs))
6941 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6942 if (spec == error_mark_node)
6944 new_specs = add_exception_specifier (new_specs, spec, complain);
6945 specs = TREE_CHAIN (specs);
6951 /* Substitute into the PARMS of a call-declarator. */
6954 tsubst_call_declarator_parms (tree parms,
6956 tsubst_flags_t complain,
6963 if (!parms || parms == void_list_node)
6966 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6967 args, complain, in_decl);
6969 /* Figure out the type of this parameter. */
6970 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6972 /* Figure out the default argument as well. Note that we use
6973 tsubst_expr since the default argument is really an expression. */
6974 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6976 /* Chain this parameter on to the front of those we have already
6977 processed. We don't use hash_tree_cons because that function
6978 doesn't check TREE_PARMLIST. */
6979 new_parms = tree_cons (defarg, type, new_parms);
6984 /* Take the tree structure T and replace template parameters used
6985 therein with the argument vector ARGS. IN_DECL is an associated
6986 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6987 Issue error and warning messages under control of COMPLAIN. Note
6988 that we must be relatively non-tolerant of extensions here, in
6989 order to preserve conformance; if we allow substitutions that
6990 should not be allowed, we may allow argument deductions that should
6991 not succeed, and therefore report ambiguous overload situations
6992 where there are none. In theory, we could allow the substitution,
6993 but indicate that it should have failed, and allow our caller to
6994 make sure that the right thing happens, but we don't try to do this
6997 This function is used for dealing with types, decls and the like;
6998 for expressions, use tsubst_expr or tsubst_copy. */
7001 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7005 if (t == NULL_TREE || t == error_mark_node
7006 || t == integer_type_node
7007 || t == void_type_node
7008 || t == char_type_node
7009 || t == unknown_type_node
7010 || TREE_CODE (t) == NAMESPACE_DECL)
7014 return tsubst_decl (t, args, complain);
7016 if (TREE_CODE (t) == IDENTIFIER_NODE)
7017 type = IDENTIFIER_TYPE_VALUE (t);
7019 type = TREE_TYPE (t);
7021 gcc_assert (type != unknown_type_node);
7024 && TREE_CODE (t) != TYPENAME_TYPE
7025 && TREE_CODE (t) != IDENTIFIER_NODE
7026 && TREE_CODE (t) != FUNCTION_TYPE
7027 && TREE_CODE (t) != METHOD_TYPE)
7028 type = tsubst (type, args, complain, in_decl);
7029 if (type == error_mark_node)
7030 return error_mark_node;
7032 switch (TREE_CODE (t))
7037 return tsubst_aggr_type (t, args, complain, in_decl,
7038 /*entering_scope=*/0);
7041 case IDENTIFIER_NODE:
7053 if (t == integer_type_node)
7056 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7057 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7061 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7063 /* The array dimension behaves like a non-type template arg,
7064 in that we want to fold it as much as possible. */
7065 max = tsubst_template_arg (omax, args, complain, in_decl);
7066 max = fold_decl_constant_value (max);
7070 Type deduction may fail for any of the following
7073 Attempting to create an array with a size that is
7074 zero or negative. */
7075 if (integer_zerop (max) && !(complain & tf_error))
7076 /* We must fail if performing argument deduction (as
7077 indicated by the state of complain), so that
7078 another substitution can be found. */
7079 return error_mark_node;
7081 else if (TREE_CODE (max) == INTEGER_CST
7082 && INT_CST_LT (max, integer_zero_node))
7084 if (complain & tf_error)
7085 error ("creating array with negative size (%qE)", max);
7087 return error_mark_node;
7090 return compute_array_index_type (NULL_TREE, max);
7093 case TEMPLATE_TYPE_PARM:
7094 case TEMPLATE_TEMPLATE_PARM:
7095 case BOUND_TEMPLATE_TEMPLATE_PARM:
7096 case TEMPLATE_PARM_INDEX:
7101 tree arg = NULL_TREE;
7105 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7106 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7107 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7108 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7110 idx = TEMPLATE_TYPE_IDX (t);
7111 level = TEMPLATE_TYPE_LEVEL (t);
7115 idx = TEMPLATE_PARM_IDX (t);
7116 level = TEMPLATE_PARM_LEVEL (t);
7119 levels = TMPL_ARGS_DEPTH (args);
7120 if (level <= levels)
7121 arg = TMPL_ARG (args, level, idx);
7123 if (arg == error_mark_node)
7124 return error_mark_node;
7125 else if (arg != NULL_TREE)
7127 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7129 gcc_assert (TYPE_P (arg));
7130 return cp_build_qualified_type_real
7131 (arg, cp_type_quals (arg) | cp_type_quals (t),
7132 complain | tf_ignore_bad_quals);
7134 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7136 /* We are processing a type constructed from a
7137 template template parameter. */
7138 tree argvec = tsubst (TYPE_TI_ARGS (t),
7139 args, complain, in_decl);
7140 if (argvec == error_mark_node)
7141 return error_mark_node;
7143 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7144 are resolving nested-types in the signature of a
7145 member function templates. Otherwise ARG is a
7146 TEMPLATE_DECL and is the real template to be
7148 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7149 arg = TYPE_NAME (arg);
7151 r = lookup_template_class (arg,
7154 /*entering_scope=*/0,
7156 return cp_build_qualified_type_real
7157 (r, TYPE_QUALS (t), complain);
7160 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7165 /* This can happen during the attempted tsubst'ing in
7166 unify. This means that we don't yet have any information
7167 about the template parameter in question. */
7170 /* If we get here, we must have been looking at a parm for a
7171 more deeply nested template. Make a new version of this
7172 template parameter, but with a lower level. */
7173 switch (TREE_CODE (t))
7175 case TEMPLATE_TYPE_PARM:
7176 case TEMPLATE_TEMPLATE_PARM:
7177 case BOUND_TEMPLATE_TEMPLATE_PARM:
7178 if (cp_type_quals (t))
7180 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7181 r = cp_build_qualified_type_real
7182 (r, cp_type_quals (t),
7183 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7184 ? tf_ignore_bad_quals : 0));
7189 TEMPLATE_TYPE_PARM_INDEX (r)
7190 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7192 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7193 TYPE_MAIN_VARIANT (r) = r;
7194 TYPE_POINTER_TO (r) = NULL_TREE;
7195 TYPE_REFERENCE_TO (r) = NULL_TREE;
7197 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7199 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7201 if (argvec == error_mark_node)
7202 return error_mark_node;
7204 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7205 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7210 case TEMPLATE_PARM_INDEX:
7211 r = reduce_template_parm_level (t, type, levels);
7223 tree purpose, value, chain;
7225 if (t == void_list_node)
7228 purpose = TREE_PURPOSE (t);
7231 purpose = tsubst (purpose, args, complain, in_decl);
7232 if (purpose == error_mark_node)
7233 return error_mark_node;
7235 value = TREE_VALUE (t);
7238 value = tsubst (value, args, complain, in_decl);
7239 if (value == error_mark_node)
7240 return error_mark_node;
7242 chain = TREE_CHAIN (t);
7243 if (chain && chain != void_type_node)
7245 chain = tsubst (chain, args, complain, in_decl);
7246 if (chain == error_mark_node)
7247 return error_mark_node;
7249 if (purpose == TREE_PURPOSE (t)
7250 && value == TREE_VALUE (t)
7251 && chain == TREE_CHAIN (t))
7253 return hash_tree_cons (purpose, value, chain);
7257 /* We should never be tsubsting a binfo. */
7261 /* A vector of template arguments. */
7263 return tsubst_template_args (t, args, complain, in_decl);
7266 case REFERENCE_TYPE:
7268 enum tree_code code;
7270 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7273 code = TREE_CODE (t);
7278 Type deduction may fail for any of the following
7281 -- Attempting to create a pointer to reference type.
7282 -- Attempting to create a reference to a reference type or
7283 a reference to void. */
7284 if (TREE_CODE (type) == REFERENCE_TYPE
7285 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7287 static location_t last_loc;
7289 /* We keep track of the last time we issued this error
7290 message to avoid spewing a ton of messages during a
7291 single bad template instantiation. */
7292 if (complain & tf_error
7293 #ifdef USE_MAPPED_LOCATION
7294 && last_loc != input_location
7296 && (last_loc.line != input_line
7297 || last_loc.file != input_filename)
7301 if (TREE_CODE (type) == VOID_TYPE)
7302 error ("forming reference to void");
7304 error ("forming %s to reference type %qT",
7305 (code == POINTER_TYPE) ? "pointer" : "reference",
7307 last_loc = input_location;
7310 return error_mark_node;
7312 else if (code == POINTER_TYPE)
7314 r = build_pointer_type (type);
7315 if (TREE_CODE (type) == METHOD_TYPE)
7316 r = build_ptrmemfunc_type (r);
7319 r = build_reference_type (type);
7320 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7322 if (r != error_mark_node)
7323 /* Will this ever be needed for TYPE_..._TO values? */
7330 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7331 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7335 Type deduction may fail for any of the following
7338 -- Attempting to create "pointer to member of T" when T
7339 is not a class type. */
7340 if (complain & tf_error)
7341 error ("creating pointer to member of non-class type %qT", r);
7342 return error_mark_node;
7344 if (TREE_CODE (type) == REFERENCE_TYPE)
7346 if (complain & tf_error)
7347 error ("creating pointer to member reference type %qT", type);
7348 return error_mark_node;
7350 if (TREE_CODE (type) == VOID_TYPE)
7352 if (complain & tf_error)
7353 error ("creating pointer to member of type void");
7354 return error_mark_node;
7356 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7357 if (TREE_CODE (type) == FUNCTION_TYPE)
7359 /* The type of the implicit object parameter gets its
7360 cv-qualifiers from the FUNCTION_TYPE. */
7362 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7363 cp_type_quals (type));
7365 method_type = build_method_type_directly (this_type,
7367 TYPE_ARG_TYPES (type));
7368 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7369 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7373 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7382 fntype = tsubst_function_type (t, args, complain, in_decl);
7383 if (fntype == error_mark_node)
7384 return error_mark_node;
7386 /* Substitute the exception specification. */
7387 specs = tsubst_exception_specification (t, args, complain,
7389 if (specs == error_mark_node)
7390 return error_mark_node;
7392 fntype = build_exception_variant (fntype, specs);
7397 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7398 if (domain == error_mark_node)
7399 return error_mark_node;
7401 /* As an optimization, we avoid regenerating the array type if
7402 it will obviously be the same as T. */
7403 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7406 /* These checks should match the ones in grokdeclarator.
7410 The deduction may fail for any of the following reasons:
7412 -- Attempting to create an array with an element type that
7413 is void, a function type, or a reference type, or [DR337]
7414 an abstract class type. */
7415 if (TREE_CODE (type) == VOID_TYPE
7416 || TREE_CODE (type) == FUNCTION_TYPE
7417 || TREE_CODE (type) == REFERENCE_TYPE)
7419 if (complain & tf_error)
7420 error ("creating array of %qT", type);
7421 return error_mark_node;
7423 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7425 if (complain & tf_error)
7426 error ("creating array of %qT, which is an abstract class type",
7428 return error_mark_node;
7431 r = build_cplus_array_type (type, domain);
7438 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7439 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7441 if (e1 == error_mark_node || e2 == error_mark_node)
7442 return error_mark_node;
7444 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7450 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7451 if (e == error_mark_node)
7452 return error_mark_node;
7454 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7459 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7460 in_decl, /*entering_scope=*/1);
7461 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7464 if (ctx == error_mark_node || f == error_mark_node)
7465 return error_mark_node;
7467 if (!IS_AGGR_TYPE (ctx))
7469 if (complain & tf_error)
7470 error ("%qT is not a class, struct, or union type", ctx);
7471 return error_mark_node;
7473 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7475 /* Normally, make_typename_type does not require that the CTX
7476 have complete type in order to allow things like:
7478 template <class T> struct S { typename S<T>::X Y; };
7480 But, such constructs have already been resolved by this
7481 point, so here CTX really should have complete type, unless
7482 it's a partial instantiation. */
7483 ctx = complete_type (ctx);
7484 if (!COMPLETE_TYPE_P (ctx))
7486 if (complain & tf_error)
7487 cxx_incomplete_type_error (NULL_TREE, ctx);
7488 return error_mark_node;
7492 f = make_typename_type (ctx, f, typename_type,
7493 (complain & tf_error) | tf_keep_type_decl);
7494 if (f == error_mark_node)
7496 if (TREE_CODE (f) == TYPE_DECL)
7498 complain |= tf_ignore_bad_quals;
7502 if (TREE_CODE (f) != TYPENAME_TYPE)
7504 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7505 error ("%qT resolves to %qT, which is not an enumeration type",
7507 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7508 error ("%qT resolves to %qT, which is is not a class type",
7512 return cp_build_qualified_type_real
7513 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7516 case UNBOUND_CLASS_TEMPLATE:
7518 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7519 in_decl, /*entering_scope=*/1);
7520 tree name = TYPE_IDENTIFIER (t);
7521 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7523 if (ctx == error_mark_node || name == error_mark_node)
7524 return error_mark_node;
7527 parm_list = tsubst_template_parms (parm_list, args, complain);
7528 return make_unbound_class_template (ctx, name, parm_list, complain);
7538 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7539 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7540 if (e1 == error_mark_node || e2 == error_mark_node)
7541 return error_mark_node;
7543 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7548 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7549 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7550 if (e1 == error_mark_node || e2 == error_mark_node)
7551 return error_mark_node;
7553 return build_qualified_name (/*type=*/NULL_TREE,
7554 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7561 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7562 complain, in_decl));
7563 return cp_build_qualified_type_real (type,
7565 | cp_type_quals (type),
7570 sorry ("use of %qs in template",
7571 tree_code_name [(int) TREE_CODE (t)]);
7572 return error_mark_node;
7576 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7577 type of the expression on the left-hand side of the "." or "->"
7581 tsubst_baselink (tree baselink, tree object_type,
7582 tree args, tsubst_flags_t complain, tree in_decl)
7585 tree qualifying_scope;
7587 tree template_args = 0;
7588 bool template_id_p = false;
7590 /* A baselink indicates a function from a base class. The
7591 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7592 non-dependent types; otherwise, the lookup could not have
7593 succeeded. However, they may indicate bases of the template
7594 class, rather than the instantiated class.
7596 In addition, lookups that were not ambiguous before may be
7597 ambiguous now. Therefore, we perform the lookup again. */
7598 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7599 fns = BASELINK_FUNCTIONS (baselink);
7600 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7602 template_id_p = true;
7603 template_args = TREE_OPERAND (fns, 1);
7604 fns = TREE_OPERAND (fns, 0);
7606 template_args = tsubst_template_args (template_args, args,
7609 name = DECL_NAME (get_first_fn (fns));
7610 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7612 /* If lookup found a single function, mark it as used at this
7613 point. (If it lookup found multiple functions the one selected
7614 later by overload resolution will be marked as used at that
7616 if (BASELINK_P (baselink))
7617 fns = BASELINK_FUNCTIONS (baselink);
7618 if (!template_id_p && !really_overloaded_fn (fns))
7619 mark_used (OVL_CURRENT (fns));
7621 /* Add back the template arguments, if present. */
7622 if (BASELINK_P (baselink) && template_id_p)
7623 BASELINK_FUNCTIONS (baselink)
7624 = build_nt (TEMPLATE_ID_EXPR,
7625 BASELINK_FUNCTIONS (baselink),
7629 object_type = current_class_type;
7630 return adjust_result_of_qualified_name_lookup (baselink,
7635 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7636 true if the qualified-id will be a postfix-expression in-and-of
7637 itself; false if more of the postfix-expression follows the
7638 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7642 tsubst_qualified_id (tree qualified_id, tree args,
7643 tsubst_flags_t complain, tree in_decl,
7644 bool done, bool address_p)
7652 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7654 /* Figure out what name to look up. */
7655 name = TREE_OPERAND (qualified_id, 1);
7656 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7659 template_args = TREE_OPERAND (name, 1);
7661 template_args = tsubst_template_args (template_args, args,
7663 name = TREE_OPERAND (name, 0);
7667 is_template = false;
7668 template_args = NULL_TREE;
7671 /* Substitute into the qualifying scope. When there are no ARGS, we
7672 are just trying to simplify a non-dependent expression. In that
7673 case the qualifying scope may be dependent, and, in any case,
7674 substituting will not help. */
7675 scope = TREE_OPERAND (qualified_id, 0);
7678 scope = tsubst (scope, args, complain, in_decl);
7679 expr = tsubst_copy (name, args, complain, in_decl);
7684 if (dependent_type_p (scope))
7685 return build_qualified_name (/*type=*/NULL_TREE,
7687 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7689 if (!BASELINK_P (name) && !DECL_P (expr))
7691 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7692 /* If this were actually a destructor call, it would have been
7693 parsed as such by the parser. */
7694 expr = error_mark_node;
7696 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7697 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7698 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7700 if (complain & tf_error)
7702 error ("dependent-name %qE is parsed as a non-type, but "
7703 "instantiation yields a type", qualified_id);
7704 inform ("say %<typename %E%> if a type is meant", qualified_id);
7706 return error_mark_node;
7712 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7714 /* Remember that there was a reference to this entity. */
7718 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7720 if (complain & tf_error)
7721 qualified_name_lookup_error (scope,
7722 TREE_OPERAND (qualified_id, 1),
7724 return error_mark_node;
7728 expr = lookup_template_function (expr, template_args);
7730 if (expr == error_mark_node && complain & tf_error)
7731 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7733 else if (TYPE_P (scope))
7735 expr = (adjust_result_of_qualified_name_lookup
7736 (expr, scope, current_class_type));
7737 expr = (finish_qualified_id_expr
7738 (scope, expr, done, address_p,
7739 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7740 /*template_arg_p=*/false));
7743 if (TREE_CODE (expr) != SCOPE_REF)
7744 expr = convert_from_reference (expr);
7749 /* Like tsubst, but deals with expressions. This function just replaces
7750 template parms; to finish processing the resultant expression, use
7754 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7756 enum tree_code code;
7759 if (t == NULL_TREE || t == error_mark_node)
7762 code = TREE_CODE (t);
7767 r = retrieve_local_specialization (t);
7768 gcc_assert (r != NULL);
7777 if (DECL_TEMPLATE_PARM_P (t))
7778 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7779 /* There is no need to substitute into namespace-scope
7781 if (DECL_NAMESPACE_SCOPE_P (t))
7783 /* If ARGS is NULL, then T is known to be non-dependent. */
7784 if (args == NULL_TREE)
7785 return integral_constant_value (t);
7787 /* Unfortunately, we cannot just call lookup_name here.
7790 template <int I> int f() {
7792 struct S { void g() { E e = a; } };
7795 When we instantiate f<7>::S::g(), say, lookup_name is not
7796 clever enough to find f<7>::a. */
7798 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7799 /*entering_scope=*/0);
7801 for (v = TYPE_VALUES (enum_type);
7804 if (TREE_PURPOSE (v) == DECL_NAME (t))
7805 return TREE_VALUE (v);
7807 /* We didn't find the name. That should never happen; if
7808 name-lookup found it during preliminary parsing, we
7809 should find it again here during instantiation. */
7815 if (DECL_CONTEXT (t))
7819 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7820 /*entering_scope=*/1);
7821 if (ctx != DECL_CONTEXT (t))
7823 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7826 if (complain & tf_error)
7827 error ("using invalid field %qD", t);
7828 return error_mark_node;
7838 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7839 || local_variable_p (t))
7840 t = tsubst (t, args, complain, in_decl);
7845 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7848 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7849 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7850 args, complain, in_decl);
7851 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7852 return tsubst (t, args, complain, in_decl);
7853 else if (DECL_CLASS_SCOPE_P (t)
7854 && uses_template_parms (DECL_CONTEXT (t)))
7856 /* Template template argument like the following example need
7859 template <template <class> class TT> struct C {};
7860 template <class T> struct D {
7861 template <class U> struct E {};
7866 We are processing the template argument `E' in #1 for
7867 the template instantiation #2. Originally, `E' is a
7868 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7869 have to substitute this with one having context `D<int>'. */
7871 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7872 return lookup_field (context, DECL_NAME(t), 0, false);
7875 /* Ordinary template template argument. */
7879 case REINTERPRET_CAST_EXPR:
7880 case CONST_CAST_EXPR:
7881 case STATIC_CAST_EXPR:
7882 case DYNAMIC_CAST_EXPR:
7885 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7886 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7890 case TRUTH_NOT_EXPR:
7893 case UNARY_PLUS_EXPR: /* Unary + */
7902 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7903 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7910 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7911 name = TREE_OPERAND (t, 1);
7912 if (TREE_CODE (name) == BIT_NOT_EXPR)
7914 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7916 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7918 else if (TREE_CODE (name) == SCOPE_REF
7919 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7921 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7923 name = TREE_OPERAND (name, 1);
7924 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7926 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7927 name = build_qualified_name (/*type=*/NULL_TREE,
7929 /*template_p=*/false);
7931 else if (TREE_CODE (name) == BASELINK)
7932 name = tsubst_baselink (name,
7933 non_reference (TREE_TYPE (object)),
7937 name = tsubst_copy (name, args, complain, in_decl);
7938 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7944 case TRUNC_DIV_EXPR:
7946 case FLOOR_DIV_EXPR:
7947 case ROUND_DIV_EXPR:
7948 case EXACT_DIV_EXPR:
7952 case TRUNC_MOD_EXPR:
7953 case FLOOR_MOD_EXPR:
7954 case TRUTH_ANDIF_EXPR:
7955 case TRUTH_ORIF_EXPR:
7956 case TRUTH_AND_EXPR:
7973 case PREDECREMENT_EXPR:
7974 case PREINCREMENT_EXPR:
7975 case POSTDECREMENT_EXPR:
7976 case POSTINCREMENT_EXPR:
7978 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7979 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7982 return build_qualified_name (/*type=*/NULL_TREE,
7983 tsubst_copy (TREE_OPERAND (t, 0),
7984 args, complain, in_decl),
7985 tsubst_copy (TREE_OPERAND (t, 1),
7986 args, complain, in_decl),
7987 QUALIFIED_NAME_IS_TEMPLATE (t));
7992 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7993 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7994 NULL_TREE, NULL_TREE);
7997 return build_nt (code,
7998 tsubst_copy (TREE_OPERAND (t, 0), args,
8000 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
8006 case PSEUDO_DTOR_EXPR:
8009 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8010 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8011 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8012 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8019 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8020 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8021 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8022 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
8029 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8030 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8031 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8032 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8036 case TEMPLATE_ID_EXPR:
8038 /* Substituted template arguments */
8039 tree fn = TREE_OPERAND (t, 0);
8040 tree targs = TREE_OPERAND (t, 1);
8042 fn = tsubst_copy (fn, args, complain, in_decl);
8044 targs = tsubst_template_args (targs, args, complain, in_decl);
8046 return lookup_template_function (fn, targs);
8051 tree purpose, value, chain;
8053 if (t == void_list_node)
8056 purpose = TREE_PURPOSE (t);
8058 purpose = tsubst_copy (purpose, args, complain, in_decl);
8059 value = TREE_VALUE (t);
8061 value = tsubst_copy (value, args, complain, in_decl);
8062 chain = TREE_CHAIN (t);
8063 if (chain && chain != void_type_node)
8064 chain = tsubst_copy (chain, args, complain, in_decl);
8065 if (purpose == TREE_PURPOSE (t)
8066 && value == TREE_VALUE (t)
8067 && chain == TREE_CHAIN (t))
8069 return tree_cons (purpose, value, chain);
8076 case TEMPLATE_TYPE_PARM:
8077 case TEMPLATE_TEMPLATE_PARM:
8078 case BOUND_TEMPLATE_TEMPLATE_PARM:
8079 case TEMPLATE_PARM_INDEX:
8081 case REFERENCE_TYPE:
8087 case UNBOUND_CLASS_TEMPLATE:
8090 return tsubst (t, args, complain, in_decl);
8092 case IDENTIFIER_NODE:
8093 if (IDENTIFIER_TYPENAME_P (t))
8095 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8096 return mangle_conv_op_name_for_type (new_type);
8102 /* This is handled by tsubst_copy_and_build. */
8106 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8108 tsubst (TREE_TYPE (t), args, complain, in_decl));
8110 case CLEANUP_POINT_EXPR:
8111 /* We shouldn't have built any of these during initial template
8112 generation. Instead, they should be built during instantiation
8113 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8117 mark_used (TREE_OPERAND (t, 1));
8125 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
8128 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
8131 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
8133 tree purpose, value, chain;
8138 if (TREE_CODE (t) != TREE_LIST)
8139 return tsubst_copy_and_build (t, args, complain, in_decl,
8140 /*function_p=*/false);
8142 if (t == void_list_node)
8145 purpose = TREE_PURPOSE (t);
8147 purpose = RECUR (purpose);
8148 value = TREE_VALUE (t);
8150 value = RECUR (value);
8151 chain = TREE_CHAIN (t);
8152 if (chain && chain != void_type_node)
8153 chain = RECUR (chain);
8154 return tree_cons (purpose, value, chain);
8158 /* Like tsubst_copy for expressions, etc. but also does semantic
8162 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8166 if (t == NULL_TREE || t == error_mark_node)
8169 if (EXPR_HAS_LOCATION (t))
8170 input_location = EXPR_LOCATION (t);
8171 if (STATEMENT_CODE_P (TREE_CODE (t)))
8172 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8174 switch (TREE_CODE (t))
8176 case STATEMENT_LIST:
8178 tree_stmt_iterator i;
8179 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8180 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8184 case CTOR_INITIALIZER:
8185 finish_mem_initializers (tsubst_initializer_list
8186 (TREE_OPERAND (t, 0), args));
8190 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8191 args, complain, in_decl));
8195 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8196 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8197 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8199 finish_expr_stmt (tmp);
8203 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8204 args, complain, in_decl));
8212 decl = DECL_EXPR_DECL (t);
8213 if (TREE_CODE (decl) == LABEL_DECL)
8214 finish_label_decl (DECL_NAME (decl));
8215 else if (TREE_CODE (decl) == USING_DECL)
8217 tree scope = USING_DECL_SCOPE (decl);
8218 tree name = DECL_NAME (decl);
8221 scope = tsubst_expr (scope, args, complain, in_decl);
8222 decl = lookup_qualified_name (scope, name,
8223 /*is_type_p=*/false,
8224 /*complain=*/false);
8225 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8226 qualified_name_lookup_error (scope, name, decl);
8228 do_local_using_decl (decl, scope, name);
8232 init = DECL_INITIAL (decl);
8233 decl = tsubst (decl, args, complain, in_decl);
8234 if (decl != error_mark_node)
8237 DECL_INITIAL (decl) = error_mark_node;
8238 /* By marking the declaration as instantiated, we avoid
8239 trying to instantiate it. Since instantiate_decl can't
8240 handle local variables, and since we've already done
8241 all that needs to be done, that's the right thing to
8243 if (TREE_CODE (decl) == VAR_DECL)
8244 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8245 if (TREE_CODE (decl) == VAR_DECL
8246 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8247 /* Anonymous aggregates are a special case. */
8248 finish_anon_union (decl);
8251 maybe_push_decl (decl);
8252 if (TREE_CODE (decl) == VAR_DECL
8253 && DECL_PRETTY_FUNCTION_P (decl))
8255 /* For __PRETTY_FUNCTION__ we have to adjust the
8257 const char *const name
8258 = cxx_printable_name (current_function_decl, 2);
8259 init = cp_fname_init (name, &TREE_TYPE (decl));
8262 init = tsubst_expr (init, args, complain, in_decl);
8263 finish_decl (decl, init, NULL_TREE);
8268 /* A DECL_EXPR can also be used as an expression, in the condition
8269 clause of an if/for/while construct. */
8274 stmt = begin_for_stmt ();
8275 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8276 finish_for_init_stmt (stmt);
8277 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8278 finish_for_cond (tmp, stmt);
8279 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8280 finish_for_expr (tmp, stmt);
8281 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8282 finish_for_stmt (stmt);
8286 stmt = begin_while_stmt ();
8287 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8288 finish_while_stmt_cond (tmp, stmt);
8289 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8290 finish_while_stmt (stmt);
8294 stmt = begin_do_stmt ();
8295 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8296 finish_do_body (stmt);
8297 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8298 finish_do_stmt (tmp, stmt);
8302 stmt = begin_if_stmt ();
8303 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8304 finish_if_stmt_cond (tmp, stmt);
8305 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8306 finish_then_clause (stmt);
8308 if (ELSE_CLAUSE (t))
8310 begin_else_clause (stmt);
8311 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8312 finish_else_clause (stmt);
8315 finish_if_stmt (stmt);
8319 if (BIND_EXPR_BODY_BLOCK (t))
8320 stmt = begin_function_body ();
8322 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8323 ? BCS_TRY_BLOCK : 0);
8325 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8327 if (BIND_EXPR_BODY_BLOCK (t))
8328 finish_function_body (stmt);
8330 finish_compound_stmt (stmt);
8334 finish_break_stmt ();
8338 finish_continue_stmt ();
8342 stmt = begin_switch_stmt ();
8343 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8344 finish_switch_cond (tmp, stmt);
8345 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8346 finish_switch_stmt (stmt);
8349 case CASE_LABEL_EXPR:
8350 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8351 tsubst_expr (CASE_HIGH (t), args, complain,
8356 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8360 tmp = GOTO_DESTINATION (t);
8361 if (TREE_CODE (tmp) != LABEL_DECL)
8362 /* Computed goto's must be tsubst'd into. On the other hand,
8363 non-computed gotos must not be; the identifier in question
8364 will have no binding. */
8365 tmp = tsubst_expr (tmp, args, complain, in_decl);
8367 tmp = DECL_NAME (tmp);
8368 finish_goto_stmt (tmp);
8372 tmp = finish_asm_stmt
8373 (ASM_VOLATILE_P (t),
8374 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8375 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
8376 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
8377 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
8379 tree asm_expr = tmp;
8380 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8381 asm_expr = TREE_OPERAND (asm_expr, 0);
8382 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8389 stmt = begin_try_block ();
8390 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8391 finish_cleanup_try_block (stmt);
8392 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8398 if (FN_TRY_BLOCK_P (t))
8399 stmt = begin_function_try_block ();
8401 stmt = begin_try_block ();
8403 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8405 if (FN_TRY_BLOCK_P (t))
8406 finish_function_try_block (stmt);
8408 finish_try_block (stmt);
8410 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8411 if (FN_TRY_BLOCK_P (t))
8412 finish_function_handler_sequence (stmt);
8414 finish_handler_sequence (stmt);
8422 stmt = begin_handler ();
8423 if (HANDLER_PARMS (t))
8425 decl = HANDLER_PARMS (t);
8426 decl = tsubst (decl, args, complain, in_decl);
8427 /* Prevent instantiate_decl from trying to instantiate
8428 this variable. We've already done all that needs to be
8430 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8434 finish_handler_parms (decl, stmt);
8435 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8436 finish_handler (stmt);
8441 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8445 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8447 return tsubst_copy_and_build (t, args, complain, in_decl,
8448 /*function_p=*/false);
8454 /* T is a postfix-expression that is not being used in a function
8455 call. Return the substituted version of T. */
8458 tsubst_non_call_postfix_expression (tree t, tree args,
8459 tsubst_flags_t complain,
8462 if (TREE_CODE (t) == SCOPE_REF)
8463 t = tsubst_qualified_id (t, args, complain, in_decl,
8464 /*done=*/false, /*address_p=*/false);
8466 t = tsubst_copy_and_build (t, args, complain, in_decl,
8467 /*function_p=*/false);
8472 /* Like tsubst but deals with expressions and performs semantic
8473 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8476 tsubst_copy_and_build (tree t,
8478 tsubst_flags_t complain,
8482 #define RECUR(NODE) \
8483 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8487 if (t == NULL_TREE || t == error_mark_node)
8490 switch (TREE_CODE (t))
8495 case IDENTIFIER_NODE:
8499 bool non_integral_constant_expression_p;
8500 const char *error_msg;
8502 if (IDENTIFIER_TYPENAME_P (t))
8504 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8505 t = mangle_conv_op_name_for_type (new_type);
8508 /* Look up the name. */
8509 decl = lookup_name (t, 0);
8511 /* By convention, expressions use ERROR_MARK_NODE to indicate
8512 failure, not NULL_TREE. */
8513 if (decl == NULL_TREE)
8514 decl = error_mark_node;
8516 decl = finish_id_expression (t, decl, NULL_TREE,
8518 /*integral_constant_expression_p=*/false,
8519 /*allow_non_integral_constant_expression_p=*/false,
8520 &non_integral_constant_expression_p,
8521 /*template_p=*/false,
8523 /*address_p=*/false,
8524 /*template_arg_p=*/false,
8528 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8529 decl = unqualified_name_lookup_error (decl);
8533 case TEMPLATE_ID_EXPR:
8536 tree template = RECUR (TREE_OPERAND (t, 0));
8537 tree targs = TREE_OPERAND (t, 1);
8540 targs = tsubst_template_args (targs, args, complain, in_decl);
8542 if (TREE_CODE (template) == COMPONENT_REF)
8544 object = TREE_OPERAND (template, 0);
8545 template = TREE_OPERAND (template, 1);
8549 template = lookup_template_function (template, targs);
8552 return build3 (COMPONENT_REF, TREE_TYPE (template),
8553 object, template, NULL_TREE);
8560 tree r = RECUR (TREE_OPERAND (t, 0));
8562 if (REFERENCE_REF_P (t))
8564 /* A type conversion to reference type will be enclosed in
8565 such an indirect ref, but the substitution of the cast
8566 will have also added such an indirect ref. */
8567 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8568 r = convert_from_reference (r);
8571 r = build_x_indirect_ref (r, "unary *");
8577 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8578 RECUR (TREE_OPERAND (t, 0)));
8581 return build_functional_cast
8582 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8583 RECUR (TREE_OPERAND (t, 0)));
8585 case REINTERPRET_CAST_EXPR:
8586 return build_reinterpret_cast
8587 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8588 RECUR (TREE_OPERAND (t, 0)));
8590 case CONST_CAST_EXPR:
8591 return build_const_cast
8592 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8593 RECUR (TREE_OPERAND (t, 0)));
8595 case DYNAMIC_CAST_EXPR:
8596 return build_dynamic_cast
8597 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8598 RECUR (TREE_OPERAND (t, 0)));
8600 case STATIC_CAST_EXPR:
8601 return build_static_cast
8602 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8603 RECUR (TREE_OPERAND (t, 0)));
8605 case POSTDECREMENT_EXPR:
8606 case POSTINCREMENT_EXPR:
8607 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8608 args, complain, in_decl);
8609 return build_x_unary_op (TREE_CODE (t), op1);
8611 case PREDECREMENT_EXPR:
8612 case PREINCREMENT_EXPR:
8616 case TRUTH_NOT_EXPR:
8617 case UNARY_PLUS_EXPR: /* Unary + */
8620 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8623 op1 = TREE_OPERAND (t, 0);
8624 if (TREE_CODE (op1) == SCOPE_REF)
8625 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8626 /*done=*/true, /*address_p=*/true);
8628 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8630 if (TREE_CODE (op1) == LABEL_DECL)
8631 return finish_label_address_expr (DECL_NAME (op1));
8632 return build_x_unary_op (ADDR_EXPR, op1);
8637 case TRUNC_DIV_EXPR:
8639 case FLOOR_DIV_EXPR:
8640 case ROUND_DIV_EXPR:
8641 case EXACT_DIV_EXPR:
8645 case TRUNC_MOD_EXPR:
8646 case FLOOR_MOD_EXPR:
8647 case TRUTH_ANDIF_EXPR:
8648 case TRUTH_ORIF_EXPR:
8649 case TRUTH_AND_EXPR:
8665 return build_x_binary_op
8667 RECUR (TREE_OPERAND (t, 0)),
8668 RECUR (TREE_OPERAND (t, 1)),
8669 /*overloaded_p=*/NULL);
8672 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8673 /*address_p=*/false);
8675 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8676 args, complain, in_decl);
8677 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8678 /*overloaded_p=*/NULL);
8682 op1 = TREE_OPERAND (t, 0);
8685 /* When there are no ARGS, we are trying to evaluate a
8686 non-dependent expression from the parser. Trying to do
8687 the substitutions may not work. */
8689 op1 = TREE_TYPE (op1);
8698 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8700 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8704 tree r = build_x_modify_expr
8705 (RECUR (TREE_OPERAND (t, 0)),
8706 TREE_CODE (TREE_OPERAND (t, 1)),
8707 RECUR (TREE_OPERAND (t, 2)));
8708 /* TREE_NO_WARNING must be set if either the expression was
8709 parenthesized or it uses an operator such as >>= rather
8710 than plain assignment. In the former case, it was already
8711 set and must be copied. In the latter case,
8712 build_x_modify_expr sets it and it must not be reset
8714 if (TREE_NO_WARNING (t))
8715 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8720 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8721 args, complain, in_decl);
8722 /* Remember that there was a reference to this entity. */
8725 return build_x_arrow (op1);
8729 (RECUR (TREE_OPERAND (t, 0)),
8730 RECUR (TREE_OPERAND (t, 1)),
8731 RECUR (TREE_OPERAND (t, 2)),
8732 RECUR (TREE_OPERAND (t, 3)),
8733 NEW_EXPR_USE_GLOBAL (t));
8736 return delete_sanity
8737 (RECUR (TREE_OPERAND (t, 0)),
8738 RECUR (TREE_OPERAND (t, 1)),
8739 DELETE_EXPR_USE_VEC (t),
8740 DELETE_EXPR_USE_GLOBAL (t));
8743 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8744 RECUR (TREE_OPERAND (t, 1)));
8753 function = TREE_OPERAND (t, 0);
8754 /* When we parsed the expression, we determined whether or
8755 not Koenig lookup should be performed. */
8756 koenig_p = KOENIG_LOOKUP_P (t);
8757 if (TREE_CODE (function) == SCOPE_REF)
8760 function = tsubst_qualified_id (function, args, complain, in_decl,
8762 /*address_p=*/false);
8766 if (TREE_CODE (function) == COMPONENT_REF)
8768 tree op = TREE_OPERAND (function, 1);
8770 qualified_p = (TREE_CODE (op) == SCOPE_REF
8772 && BASELINK_QUALIFIED_P (op)));
8775 qualified_p = false;
8777 function = tsubst_copy_and_build (function, args, complain,
8780 if (BASELINK_P (function))
8784 call_args = RECUR (TREE_OPERAND (t, 1));
8786 /* We do not perform argument-dependent lookup if normal
8787 lookup finds a non-function, in accordance with the
8788 expected resolution of DR 218. */
8790 && ((is_overloaded_fn (function)
8791 /* If lookup found a member function, the Koenig lookup is
8792 not appropriate, even if an unqualified-name was used
8793 to denote the function. */
8794 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8795 || TREE_CODE (function) == IDENTIFIER_NODE))
8796 function = perform_koenig_lookup (function, call_args);
8798 if (TREE_CODE (function) == IDENTIFIER_NODE)
8800 unqualified_name_lookup_error (function);
8801 return error_mark_node;
8804 /* Remember that there was a reference to this entity. */
8805 if (DECL_P (function))
8806 mark_used (function);
8808 if (TREE_CODE (function) == OFFSET_REF)
8809 return build_offset_ref_call_from_tree (function, call_args);
8810 if (TREE_CODE (function) == COMPONENT_REF)
8812 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8813 return finish_call_expr (function, call_args,
8814 /*disallow_virtual=*/false,
8815 /*koenig_p=*/false);
8817 return (build_new_method_call
8818 (TREE_OPERAND (function, 0),
8819 TREE_OPERAND (function, 1),
8820 call_args, NULL_TREE,
8821 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8823 return finish_call_expr (function, call_args,
8824 /*disallow_virtual=*/qualified_p,
8829 return build_x_conditional_expr
8830 (RECUR (TREE_OPERAND (t, 0)),
8831 RECUR (TREE_OPERAND (t, 1)),
8832 RECUR (TREE_OPERAND (t, 2)));
8834 case PSEUDO_DTOR_EXPR:
8835 return finish_pseudo_destructor_expr
8836 (RECUR (TREE_OPERAND (t, 0)),
8837 RECUR (TREE_OPERAND (t, 1)),
8838 RECUR (TREE_OPERAND (t, 2)));
8842 tree purpose, value, chain;
8844 if (t == void_list_node)
8847 purpose = TREE_PURPOSE (t);
8849 purpose = RECUR (purpose);
8850 value = TREE_VALUE (t);
8852 value = RECUR (value);
8853 chain = TREE_CHAIN (t);
8854 if (chain && chain != void_type_node)
8855 chain = RECUR (chain);
8856 if (purpose == TREE_PURPOSE (t)
8857 && value == TREE_VALUE (t)
8858 && chain == TREE_CHAIN (t))
8860 return tree_cons (purpose, value, chain);
8869 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8870 args, complain, in_decl);
8871 /* Remember that there was a reference to this entity. */
8872 if (DECL_P (object))
8874 object_type = TREE_TYPE (object);
8876 member = TREE_OPERAND (t, 1);
8877 if (BASELINK_P (member))
8878 member = tsubst_baselink (member,
8879 non_reference (TREE_TYPE (object)),
8880 args, complain, in_decl);
8882 member = tsubst_copy (member, args, complain, in_decl);
8883 if (member == error_mark_node)
8884 return error_mark_node;
8886 if (object_type && !CLASS_TYPE_P (object_type))
8888 if (TREE_CODE (member) == BIT_NOT_EXPR)
8889 return finish_pseudo_destructor_expr (object,
8892 else if (TREE_CODE (member) == SCOPE_REF
8893 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8894 return finish_pseudo_destructor_expr (object,
8898 else if (TREE_CODE (member) == SCOPE_REF
8899 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8904 /* Lookup the template functions now that we know what the
8906 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8907 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8908 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8909 /*is_type_p=*/false,
8910 /*complain=*/false);
8911 if (BASELINK_P (member))
8913 BASELINK_FUNCTIONS (member)
8914 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8916 member = (adjust_result_of_qualified_name_lookup
8917 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8922 qualified_name_lookup_error (object_type, tmpl, member);
8923 return error_mark_node;
8926 else if (TREE_CODE (member) == SCOPE_REF
8927 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8928 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8930 if (complain & tf_error)
8932 if (TYPE_P (TREE_OPERAND (member, 0)))
8933 error ("%qT is not a class or namespace",
8934 TREE_OPERAND (member, 0));
8936 error ("%qD is not a class or namespace",
8937 TREE_OPERAND (member, 0));
8939 return error_mark_node;
8941 else if (TREE_CODE (member) == FIELD_DECL)
8942 return finish_non_static_data_member (member, object, NULL_TREE);
8944 return finish_class_member_access_expr (object, member,
8945 /*template_p=*/false);
8950 (RECUR (TREE_OPERAND (t, 0)));
8954 VEC(constructor_elt,gc) *n;
8955 constructor_elt *ce;
8956 unsigned HOST_WIDE_INT idx;
8958 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8959 bool process_index_p;
8961 /* digest_init will do the wrong thing if we let it. */
8962 if (type && TYPE_PTRMEMFUNC_P (type))
8965 /* We do not want to process the index of aggregate
8966 initializers as they are identifier nodes which will be
8967 looked up by digest_init. */
8968 process_index_p = !(type && IS_AGGR_TYPE (type));
8970 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8971 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8973 if (ce->index && process_index_p)
8974 ce->index = RECUR (ce->index);
8975 ce->value = RECUR (ce->value);
8978 r = build_constructor (NULL_TREE, n);
8979 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8982 return digest_init (type, r);
8988 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8989 if (TYPE_P (operand_0))
8990 return get_typeid (operand_0);
8991 return build_typeid (operand_0);
9001 tree r = tsubst_copy (t, args, complain, in_decl);
9003 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
9004 /* If the original type was a reference, we'll be wrapped in
9005 the appropriate INDIRECT_REF. */
9006 r = convert_from_reference (r);
9011 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
9012 tsubst_copy (TREE_TYPE (t), args, complain,
9016 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
9020 tree old_stmt_expr = cur_stmt_expr;
9021 tree stmt_expr = begin_stmt_expr ();
9023 cur_stmt_expr = stmt_expr;
9024 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
9025 stmt_expr = finish_stmt_expr (stmt_expr, false);
9026 cur_stmt_expr = old_stmt_expr;
9032 t = tsubst_copy (t, args, complain, in_decl);
9033 /* As in finish_id_expression, we resolve enumeration constants
9034 to their underlying values. */
9035 if (TREE_CODE (t) == CONST_DECL)
9036 return DECL_INITIAL (t);
9040 /* Handle Objective-C++ constructs, if appropriate. */
9043 = objcp_tsubst_copy_and_build (t, args, complain,
9044 in_decl, /*function_p=*/false);
9048 return tsubst_copy (t, args, complain, in_decl);
9054 /* Verify that the instantiated ARGS are valid. For type arguments,
9055 make sure that the type's linkage is ok. For non-type arguments,
9056 make sure they are constants if they are integral or enumerations.
9057 Emit an error under control of COMPLAIN, and return TRUE on error. */
9060 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9062 int ix, len = DECL_NTPARMS (tmpl);
9063 bool result = false;
9065 for (ix = 0; ix != len; ix++)
9067 tree t = TREE_VEC_ELT (args, ix);
9071 /* [basic.link]: A name with no linkage (notably, the name
9072 of a class or enumeration declared in a local scope)
9073 shall not be used to declare an entity with linkage.
9074 This implies that names with no linkage cannot be used as
9075 template arguments. */
9076 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9080 /* DR 488 makes use of a type with no linkage cause
9081 type deduction to fail. */
9082 if (complain & tf_error)
9084 if (TYPE_ANONYMOUS_P (nt))
9085 error ("%qT is/uses anonymous type", t);
9087 error ("%qT uses local type %qT", t, nt);
9091 /* In order to avoid all sorts of complications, we do not
9092 allow variably-modified types as template arguments. */
9093 else if (variably_modified_type_p (t, NULL_TREE))
9095 if (complain & tf_error)
9096 error ("%qT is a variably modified type", t);
9100 /* A non-type argument of integral or enumerated type must be a
9102 else if (TREE_TYPE (t)
9103 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9104 && !TREE_CONSTANT (t))
9106 if (complain & tf_error)
9107 error ("integral expression %qE is not constant", t);
9111 if (result && (complain & tf_error))
9112 error (" trying to instantiate %qD", tmpl);
9116 /* Instantiate the indicated variable or function template TMPL with
9117 the template arguments in TARG_PTR. */
9120 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9126 if (tmpl == error_mark_node)
9127 return error_mark_node;
9129 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9131 /* If this function is a clone, handle it specially. */
9132 if (DECL_CLONED_FUNCTION_P (tmpl))
9137 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9139 if (spec == error_mark_node)
9140 return error_mark_node;
9142 /* Look for the clone. */
9143 FOR_EACH_CLONE (clone, spec)
9144 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9146 /* We should always have found the clone by now. */
9151 /* Check to see if we already have this specialization. */
9152 spec = retrieve_specialization (tmpl, targ_ptr,
9153 /*class_specializations_p=*/false);
9154 if (spec != NULL_TREE)
9157 gen_tmpl = most_general_template (tmpl);
9158 if (tmpl != gen_tmpl)
9160 /* The TMPL is a partial instantiation. To get a full set of
9161 arguments we must add the arguments used to perform the
9162 partial instantiation. */
9163 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9166 /* Check to see if we already have this specialization. */
9167 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9168 /*class_specializations_p=*/false);
9169 if (spec != NULL_TREE)
9173 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9175 return error_mark_node;
9177 /* We are building a FUNCTION_DECL, during which the access of its
9178 parameters and return types have to be checked. However this
9179 FUNCTION_DECL which is the desired context for access checking
9180 is not built yet. We solve this chicken-and-egg problem by
9181 deferring all checks until we have the FUNCTION_DECL. */
9182 push_deferring_access_checks (dk_deferred);
9184 /* Substitute template parameters. */
9185 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9186 targ_ptr, complain, gen_tmpl);
9187 if (fndecl == error_mark_node)
9188 return error_mark_node;
9190 /* Now we know the specialization, compute access previously
9192 push_access_scope (fndecl);
9193 perform_deferred_access_checks ();
9194 pop_access_scope (fndecl);
9195 pop_deferring_access_checks ();
9197 /* The DECL_TI_TEMPLATE should always be the immediate parent
9198 template, not the most general template. */
9199 DECL_TI_TEMPLATE (fndecl) = tmpl;
9201 /* If we've just instantiated the main entry point for a function,
9202 instantiate all the alternate entry points as well. We do this
9203 by cloning the instantiation of the main entry point, not by
9204 instantiating the template clones. */
9205 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9206 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9211 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9212 arguments that are being used when calling it. TARGS is a vector
9213 into which the deduced template arguments are placed.
9215 Return zero for success, 2 for an incomplete match that doesn't resolve
9216 all the types, and 1 for complete failure. An error message will be
9217 printed only for an incomplete match.
9219 If FN is a conversion operator, or we are trying to produce a specific
9220 specialization, RETURN_TYPE is the return type desired.
9222 The EXPLICIT_TARGS are explicit template arguments provided via a
9225 The parameter STRICT is one of:
9228 We are deducing arguments for a function call, as in
9232 We are deducing arguments for a conversion function, as in
9236 We are deducing arguments when doing an explicit instantiation
9237 as in [temp.explicit], when determining an explicit specialization
9238 as in [temp.expl.spec], or when taking the address of a function
9239 template, as in [temp.deduct.funcaddr]. */
9242 fn_type_unification (tree fn,
9243 tree explicit_targs,
9247 unification_kind_t strict,
9254 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9256 fntype = TREE_TYPE (fn);
9261 The specified template arguments must match the template
9262 parameters in kind (i.e., type, nontype, template), and there
9263 must not be more arguments than there are parameters;
9264 otherwise type deduction fails.
9266 Nontype arguments must match the types of the corresponding
9267 nontype template parameters, or must be convertible to the
9268 types of the corresponding nontype parameters as specified in
9269 _temp.arg.nontype_, otherwise type deduction fails.
9271 All references in the function type of the function template
9272 to the corresponding template parameters are replaced by the
9273 specified template argument values. If a substitution in a
9274 template parameter or in the function type of the function
9275 template results in an invalid type, type deduction fails. */
9277 tree converted_args;
9280 if (explicit_targs == error_mark_node)
9284 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9285 explicit_targs, NULL_TREE, tf_none,
9286 /*require_all_arguments=*/0));
9287 if (converted_args == error_mark_node)
9290 /* Substitute the explicit args into the function type. This is
9291 necessary so that, for instance, explicitly declared function
9292 arguments can match null pointed constants. If we were given
9293 an incomplete set of explicit args, we must not do semantic
9294 processing during substitution as we could create partial
9296 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9297 processing_template_decl += incomplete;
9298 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9299 processing_template_decl -= incomplete;
9301 if (fntype == error_mark_node)
9304 /* Place the explicitly specified arguments in TARGS. */
9305 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9306 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9309 parms = TYPE_ARG_TYPES (fntype);
9310 /* Never do unification on the 'this' parameter. */
9311 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9312 parms = TREE_CHAIN (parms);
9316 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9317 args = tree_cons (NULL_TREE, return_type, args);
9320 /* We allow incomplete unification without an error message here
9321 because the standard doesn't seem to explicitly prohibit it. Our
9322 callers must be ready to deal with unification failures in any
9324 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9325 targs, parms, args, /*subr=*/0,
9329 /* All is well so far. Now, check:
9333 When all template arguments have been deduced, all uses of
9334 template parameters in nondeduced contexts are replaced with
9335 the corresponding deduced argument values. If the
9336 substitution results in an invalid type, as described above,
9337 type deduction fails. */
9338 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9345 /* Adjust types before performing type deduction, as described in
9346 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9347 sections are symmetric. PARM is the type of a function parameter
9348 or the return type of the conversion function. ARG is the type of
9349 the argument passed to the call, or the type of the value
9350 initialized with the result of the conversion function. */
9353 maybe_adjust_types_for_deduction (unification_kind_t strict,
9366 /* Swap PARM and ARG throughout the remainder of this
9367 function; the handling is precisely symmetric since PARM
9368 will initialize ARG rather than vice versa. */
9376 /* There is nothing to do in this case. */
9383 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9385 /* [temp.deduct.call]
9387 If P is not a reference type:
9389 --If A is an array type, the pointer type produced by the
9390 array-to-pointer standard conversion (_conv.array_) is
9391 used in place of A for type deduction; otherwise,
9393 --If A is a function type, the pointer type produced by
9394 the function-to-pointer standard conversion
9395 (_conv.func_) is used in place of A for type deduction;
9398 --If A is a cv-qualified type, the top level
9399 cv-qualifiers of A's type are ignored for type
9401 if (TREE_CODE (*arg) == ARRAY_TYPE)
9402 *arg = build_pointer_type (TREE_TYPE (*arg));
9403 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9404 *arg = build_pointer_type (*arg);
9406 *arg = TYPE_MAIN_VARIANT (*arg);
9409 /* [temp.deduct.call]
9411 If P is a cv-qualified type, the top level cv-qualifiers
9412 of P's type are ignored for type deduction. If P is a
9413 reference type, the type referred to by P is used for
9415 *parm = TYPE_MAIN_VARIANT (*parm);
9416 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9418 *parm = TREE_TYPE (*parm);
9419 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9422 /* DR 322. For conversion deduction, remove a reference type on parm
9423 too (which has been swapped into ARG). */
9424 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9425 *arg = TREE_TYPE (*arg);
9430 /* Most parms like fn_type_unification.
9432 If SUBR is 1, we're being called recursively (to unify the
9433 arguments of a function or method parameter of a function
9437 type_unification_real (tree tparms,
9442 unification_kind_t strict,
9447 int ntparms = TREE_VEC_LENGTH (tparms);
9449 int saw_undeduced = 0;
9452 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9453 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9454 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9455 gcc_assert (ntparms > 0);
9460 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9461 | UNIFY_ALLOW_DERIVED);
9465 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9469 sub_strict = UNIFY_ALLOW_NONE;
9480 while (parms && parms != void_list_node
9481 && args && args != void_list_node)
9483 parm = TREE_VALUE (parms);
9484 parms = TREE_CHAIN (parms);
9485 arg = TREE_VALUE (args);
9486 args = TREE_CHAIN (args);
9488 if (arg == error_mark_node)
9490 if (arg == unknown_type_node)
9491 /* We can't deduce anything from this, but we might get all the
9492 template args from other function args. */
9495 /* Conversions will be performed on a function argument that
9496 corresponds with a function parameter that contains only
9497 non-deducible template parameters and explicitly specified
9498 template parameters. */
9499 if (!uses_template_parms (parm))
9504 type = TREE_TYPE (arg);
9508 if (same_type_p (parm, type))
9510 if (strict != DEDUCE_EXACT
9511 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9520 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9521 if (type_unknown_p (arg))
9523 /* [temp.deduct.type] A template-argument can be deduced from
9524 a pointer to function or pointer to member function
9525 argument if the set of overloaded functions does not
9526 contain function templates and at most one of a set of
9527 overloaded functions provides a unique match. */
9529 if (resolve_overloaded_unification
9530 (tparms, targs, parm, arg, strict, sub_strict)
9535 arg = TREE_TYPE (arg);
9536 if (arg == error_mark_node)
9541 int arg_strict = sub_strict;
9544 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9546 if (unify (tparms, targs, parm, arg, arg_strict))
9551 /* Fail if we've reached the end of the parm list, and more args
9552 are present, and the parm list isn't variadic. */
9553 if (args && args != void_list_node && parms == void_list_node)
9555 /* Fail if parms are left and they don't have default values. */
9556 if (parms && parms != void_list_node
9557 && TREE_PURPOSE (parms) == NULL_TREE)
9561 for (i = 0; i < ntparms; i++)
9562 if (!TREE_VEC_ELT (targs, i))
9564 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9566 /* If this is an undeduced nontype parameter that depends on
9567 a type parameter, try another pass; its type may have been
9568 deduced from a later argument than the one from which
9569 this parameter can be deduced. */
9570 if (TREE_CODE (tparm) == PARM_DECL
9571 && uses_template_parms (TREE_TYPE (tparm))
9572 && !saw_undeduced++)
9581 /* Subroutine of type_unification_real. Args are like the variables at the
9582 call site. ARG is an overloaded function (or template-id); we try
9583 deducing template args from each of the overloads, and if only one
9584 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9587 resolve_overloaded_unification (tree tparms,
9591 unification_kind_t strict,
9594 tree tempargs = copy_node (targs);
9598 if (TREE_CODE (arg) == ADDR_EXPR)
9600 arg = TREE_OPERAND (arg, 0);
9606 if (TREE_CODE (arg) == COMPONENT_REF)
9607 /* Handle `&x' where `x' is some static or non-static member
9609 arg = TREE_OPERAND (arg, 1);
9611 if (TREE_CODE (arg) == OFFSET_REF)
9612 arg = TREE_OPERAND (arg, 1);
9614 /* Strip baselink information. */
9615 if (BASELINK_P (arg))
9616 arg = BASELINK_FUNCTIONS (arg);
9618 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9620 /* If we got some explicit template args, we need to plug them into
9621 the affected templates before we try to unify, in case the
9622 explicit args will completely resolve the templates in question. */
9624 tree expl_subargs = TREE_OPERAND (arg, 1);
9625 arg = TREE_OPERAND (arg, 0);
9627 for (; arg; arg = OVL_NEXT (arg))
9629 tree fn = OVL_CURRENT (arg);
9632 if (TREE_CODE (fn) != TEMPLATE_DECL)
9635 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9636 expl_subargs, /*check_ret=*/false);
9639 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9640 good += try_one_overload (tparms, targs, tempargs, parm,
9641 elem, strict, sub_strict, addr_p);
9647 gcc_assert (TREE_CODE (arg) == OVERLOAD
9648 || TREE_CODE (arg) == FUNCTION_DECL);
9650 for (; arg; arg = OVL_NEXT (arg))
9651 good += try_one_overload (tparms, targs, tempargs, parm,
9652 TREE_TYPE (OVL_CURRENT (arg)),
9653 strict, sub_strict, addr_p);
9656 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9657 to function or pointer to member function argument if the set of
9658 overloaded functions does not contain function templates and at most
9659 one of a set of overloaded functions provides a unique match.
9661 So if we found multiple possibilities, we return success but don't
9666 int i = TREE_VEC_LENGTH (targs);
9668 if (TREE_VEC_ELT (tempargs, i))
9669 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9677 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9678 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9679 different overloads deduce different arguments for a given parm.
9680 ADDR_P is true if the expression for which deduction is being
9681 performed was of the form "& fn" rather than simply "fn".
9683 Returns 1 on success. */
9686 try_one_overload (tree tparms,
9691 unification_kind_t strict,
9699 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9700 to function or pointer to member function argument if the set of
9701 overloaded functions does not contain function templates and at most
9702 one of a set of overloaded functions provides a unique match.
9704 So if this is a template, just return success. */
9706 if (uses_template_parms (arg))
9709 if (TREE_CODE (arg) == METHOD_TYPE)
9710 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9712 arg = build_pointer_type (arg);
9714 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9716 /* We don't copy orig_targs for this because if we have already deduced
9717 some template args from previous args, unify would complain when we
9718 try to deduce a template parameter for the same argument, even though
9719 there isn't really a conflict. */
9720 nargs = TREE_VEC_LENGTH (targs);
9721 tempargs = make_tree_vec (nargs);
9723 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9726 /* First make sure we didn't deduce anything that conflicts with
9727 explicitly specified args. */
9728 for (i = nargs; i--; )
9730 tree elt = TREE_VEC_ELT (tempargs, i);
9731 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9735 else if (uses_template_parms (elt))
9736 /* Since we're unifying against ourselves, we will fill in
9737 template args used in the function parm list with our own
9738 template parms. Discard them. */
9739 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9740 else if (oldelt && !template_args_equal (oldelt, elt))
9744 for (i = nargs; i--; )
9746 tree elt = TREE_VEC_ELT (tempargs, i);
9749 TREE_VEC_ELT (targs, i) = elt;
9755 /* PARM is a template class (perhaps with unbound template
9756 parameters). ARG is a fully instantiated type. If ARG can be
9757 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9758 TARGS are as for unify. */
9761 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9765 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9766 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9767 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9770 /* We need to make a new template argument vector for the call to
9771 unify. If we used TARGS, we'd clutter it up with the result of
9772 the attempted unification, even if this class didn't work out.
9773 We also don't want to commit ourselves to all the unifications
9774 we've already done, since unification is supposed to be done on
9775 an argument-by-argument basis. In other words, consider the
9776 following pathological case:
9778 template <int I, int J, int K>
9781 template <int I, int J>
9782 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9784 template <int I, int J, int K>
9785 void f(S<I, J, K>, S<I, I, I>);
9794 Now, by the time we consider the unification involving `s2', we
9795 already know that we must have `f<0, 0, 0>'. But, even though
9796 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9797 because there are two ways to unify base classes of S<0, 1, 2>
9798 with S<I, I, I>. If we kept the already deduced knowledge, we
9799 would reject the possibility I=1. */
9800 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9802 /* If unification failed, we're done. */
9803 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9804 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9810 /* Given a template type PARM and a class type ARG, find the unique
9811 base type in ARG that is an instance of PARM. We do not examine
9812 ARG itself; only its base-classes. If there is not exactly one
9813 appropriate base class, return NULL_TREE. PARM may be the type of
9814 a partial specialization, as well as a plain template type. Used
9818 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9820 tree rval = NULL_TREE;
9823 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9825 binfo = TYPE_BINFO (complete_type (arg));
9827 /* The type could not be completed. */
9830 /* Walk in inheritance graph order. The search order is not
9831 important, and this avoids multiple walks of virtual bases. */
9832 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9834 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9838 /* If there is more than one satisfactory baseclass, then:
9842 If they yield more than one possible deduced A, the type
9846 if (rval && !same_type_p (r, rval))
9856 /* Returns the level of DECL, which declares a template parameter. */
9859 template_decl_level (tree decl)
9861 switch (TREE_CODE (decl))
9865 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9868 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9876 /* Decide whether ARG can be unified with PARM, considering only the
9877 cv-qualifiers of each type, given STRICT as documented for unify.
9878 Returns nonzero iff the unification is OK on that basis. */
9881 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9883 int arg_quals = cp_type_quals (arg);
9884 int parm_quals = cp_type_quals (parm);
9886 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9887 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9889 /* Although a CVR qualifier is ignored when being applied to a
9890 substituted template parameter ([8.3.2]/1 for example), that
9891 does not apply during deduction [14.8.2.4]/1, (even though
9892 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9893 this). Except when we're allowing additional CV qualifiers
9894 at the outer level [14.8.2.1]/3,1st bullet. */
9895 if ((TREE_CODE (arg) == REFERENCE_TYPE
9896 || TREE_CODE (arg) == FUNCTION_TYPE
9897 || TREE_CODE (arg) == METHOD_TYPE)
9898 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9901 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9902 && (parm_quals & TYPE_QUAL_RESTRICT))
9906 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9907 && (arg_quals & parm_quals) != parm_quals)
9910 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9911 && (parm_quals & arg_quals) != arg_quals)
9917 /* Deduce the value of template parameters. TPARMS is the (innermost)
9918 set of template parameters to a template. TARGS is the bindings
9919 for those template parameters, as determined thus far; TARGS may
9920 include template arguments for outer levels of template parameters
9921 as well. PARM is a parameter to a template function, or a
9922 subcomponent of that parameter; ARG is the corresponding argument.
9923 This function attempts to match PARM with ARG in a manner
9924 consistent with the existing assignments in TARGS. If more values
9925 are deduced, then TARGS is updated.
9927 Returns 0 if the type deduction succeeds, 1 otherwise. The
9928 parameter STRICT is a bitwise or of the following flags:
9931 Require an exact match between PARM and ARG.
9932 UNIFY_ALLOW_MORE_CV_QUAL:
9933 Allow the deduced ARG to be more cv-qualified (by qualification
9934 conversion) than ARG.
9935 UNIFY_ALLOW_LESS_CV_QUAL:
9936 Allow the deduced ARG to be less cv-qualified than ARG.
9937 UNIFY_ALLOW_DERIVED:
9938 Allow the deduced ARG to be a template base class of ARG,
9939 or a pointer to a template base class of the type pointed to by
9941 UNIFY_ALLOW_INTEGER:
9942 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9943 case for more information.
9944 UNIFY_ALLOW_OUTER_LEVEL:
9945 This is the outermost level of a deduction. Used to determine validity
9946 of qualification conversions. A valid qualification conversion must
9947 have const qualified pointers leading up to the inner type which
9948 requires additional CV quals, except at the outer level, where const
9949 is not required [conv.qual]. It would be normal to set this flag in
9950 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9951 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9952 This is the outermost level of a deduction, and PARM can be more CV
9953 qualified at this point.
9954 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9955 This is the outermost level of a deduction, and PARM can be less CV
9956 qualified at this point. */
9959 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9964 int strict_in = strict;
9966 /* I don't think this will do the right thing with respect to types.
9967 But the only case I've seen it in so far has been array bounds, where
9968 signedness is the only information lost, and I think that will be
9970 while (TREE_CODE (parm) == NOP_EXPR)
9971 parm = TREE_OPERAND (parm, 0);
9973 if (arg == error_mark_node)
9975 if (arg == unknown_type_node)
9976 /* We can't deduce anything from this, but we might get all the
9977 template args from other function args. */
9980 /* If PARM uses template parameters, then we can't bail out here,
9981 even if ARG == PARM, since we won't record unifications for the
9982 template parameters. We might need them if we're trying to
9983 figure out which of two things is more specialized. */
9984 if (arg == parm && !uses_template_parms (parm))
9987 /* Immediately reject some pairs that won't unify because of
9988 cv-qualification mismatches. */
9989 if (TREE_CODE (arg) == TREE_CODE (parm)
9991 /* It is the elements of the array which hold the cv quals of an array
9992 type, and the elements might be template type parms. We'll check
9994 && TREE_CODE (arg) != ARRAY_TYPE
9995 /* We check the cv-qualifiers when unifying with template type
9996 parameters below. We want to allow ARG `const T' to unify with
9997 PARM `T' for example, when computing which of two templates
9998 is more specialized, for example. */
9999 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
10000 && !check_cv_quals_for_unify (strict_in, arg, parm))
10003 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
10004 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
10005 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
10006 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
10007 strict &= ~UNIFY_ALLOW_DERIVED;
10008 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
10009 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
10011 switch (TREE_CODE (parm))
10013 case TYPENAME_TYPE:
10015 case UNBOUND_CLASS_TEMPLATE:
10016 /* In a type which contains a nested-name-specifier, template
10017 argument values cannot be deduced for template parameters used
10018 within the nested-name-specifier. */
10021 case TEMPLATE_TYPE_PARM:
10022 case TEMPLATE_TEMPLATE_PARM:
10023 case BOUND_TEMPLATE_TEMPLATE_PARM:
10024 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10026 if (TEMPLATE_TYPE_LEVEL (parm)
10027 != template_decl_level (tparm))
10028 /* The PARM is not one we're trying to unify. Just check
10029 to see if it matches ARG. */
10030 return (TREE_CODE (arg) == TREE_CODE (parm)
10031 && same_type_p (parm, arg)) ? 0 : 1;
10032 idx = TEMPLATE_TYPE_IDX (parm);
10033 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10034 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10036 /* Check for mixed types and values. */
10037 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10038 && TREE_CODE (tparm) != TYPE_DECL)
10039 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10040 && TREE_CODE (tparm) != TEMPLATE_DECL))
10043 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10045 /* ARG must be constructed from a template class or a template
10046 template parameter. */
10047 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10048 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
10052 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
10053 tree parmvec = TYPE_TI_ARGS (parm);
10054 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10056 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10059 /* The parameter and argument roles have to be switched here
10060 in order to handle default arguments properly. For example,
10061 template<template <class> class TT> void f(TT<int>)
10062 should be able to accept vector<int> which comes from
10063 template <class T, class Allocator = allocator>
10066 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
10067 == error_mark_node)
10070 /* Deduce arguments T, i from TT<T> or TT<i>.
10071 We check each element of PARMVEC and ARGVEC individually
10072 rather than the whole TREE_VEC since they can have
10073 different number of elements. */
10075 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10077 if (unify (tparms, targs,
10078 TREE_VEC_ELT (parmvec, i),
10079 TREE_VEC_ELT (argvec, i),
10084 arg = TYPE_TI_TEMPLATE (arg);
10086 /* Fall through to deduce template name. */
10089 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10090 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10092 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10094 /* Simple cases: Value already set, does match or doesn't. */
10095 if (targ != NULL_TREE && template_args_equal (targ, arg))
10102 /* If PARM is `const T' and ARG is only `int', we don't have
10103 a match unless we are allowing additional qualification.
10104 If ARG is `const int' and PARM is just `T' that's OK;
10105 that binds `const int' to `T'. */
10106 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10110 /* Consider the case where ARG is `const volatile int' and
10111 PARM is `const T'. Then, T should be `volatile int'. */
10112 arg = cp_build_qualified_type_real
10113 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10114 if (arg == error_mark_node)
10117 /* Simple cases: Value already set, does match or doesn't. */
10118 if (targ != NULL_TREE && same_type_p (targ, arg))
10123 /* Make sure that ARG is not a variable-sized array. (Note
10124 that were talking about variable-sized arrays (like
10125 `int[n]'), rather than arrays of unknown size (like
10126 `int[]').) We'll get very confused by such a type since
10127 the bound of the array will not be computable in an
10128 instantiation. Besides, such types are not allowed in
10129 ISO C++, so we can do as we please here. */
10130 if (variably_modified_type_p (arg, NULL_TREE))
10134 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10137 case TEMPLATE_PARM_INDEX:
10138 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10140 if (TEMPLATE_PARM_LEVEL (parm)
10141 != template_decl_level (tparm))
10142 /* The PARM is not one we're trying to unify. Just check
10143 to see if it matches ARG. */
10144 return !(TREE_CODE (arg) == TREE_CODE (parm)
10145 && cp_tree_equal (parm, arg));
10147 idx = TEMPLATE_PARM_IDX (parm);
10148 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10151 return !cp_tree_equal (targ, arg);
10153 /* [temp.deduct.type] If, in the declaration of a function template
10154 with a non-type template-parameter, the non-type
10155 template-parameter is used in an expression in the function
10156 parameter-list and, if the corresponding template-argument is
10157 deduced, the template-argument type shall match the type of the
10158 template-parameter exactly, except that a template-argument
10159 deduced from an array bound may be of any integral type.
10160 The non-type parameter might use already deduced type parameters. */
10161 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10162 if (!TREE_TYPE (arg))
10163 /* Template-parameter dependent expression. Just accept it for now.
10164 It will later be processed in convert_template_argument. */
10166 else if (same_type_p (TREE_TYPE (arg), tparm))
10168 else if ((strict & UNIFY_ALLOW_INTEGER)
10169 && (TREE_CODE (tparm) == INTEGER_TYPE
10170 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10171 /* Convert the ARG to the type of PARM; the deduced non-type
10172 template argument must exactly match the types of the
10173 corresponding parameter. */
10174 arg = fold (build_nop (TREE_TYPE (parm), arg));
10175 else if (uses_template_parms (tparm))
10176 /* We haven't deduced the type of this parameter yet. Try again
10182 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10187 /* A pointer-to-member constant can be unified only with
10188 another constant. */
10189 if (TREE_CODE (arg) != PTRMEM_CST)
10192 /* Just unify the class member. It would be useless (and possibly
10193 wrong, depending on the strict flags) to unify also
10194 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10195 arg refer to the same variable, even if through different
10196 classes. For instance:
10198 struct A { int x; };
10201 Unification of &A::x and &B::x must succeed. */
10202 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10203 PTRMEM_CST_MEMBER (arg), strict);
10208 if (TREE_CODE (arg) != POINTER_TYPE)
10211 /* [temp.deduct.call]
10213 A can be another pointer or pointer to member type that can
10214 be converted to the deduced A via a qualification
10215 conversion (_conv.qual_).
10217 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10218 This will allow for additional cv-qualification of the
10219 pointed-to types if appropriate. */
10221 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10222 /* The derived-to-base conversion only persists through one
10223 level of pointers. */
10224 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10226 return unify (tparms, targs, TREE_TYPE (parm),
10227 TREE_TYPE (arg), strict);
10230 case REFERENCE_TYPE:
10231 if (TREE_CODE (arg) != REFERENCE_TYPE)
10233 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10234 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10237 if (TREE_CODE (arg) != ARRAY_TYPE)
10239 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10240 != (TYPE_DOMAIN (arg) == NULL_TREE))
10242 if (TYPE_DOMAIN (parm) != NULL_TREE)
10247 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10248 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10250 /* Our representation of array types uses "N - 1" as the
10251 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10252 not an integer constant. */
10253 if (TREE_CODE (parm_max) == MINUS_EXPR)
10255 arg_max = fold_build2 (PLUS_EXPR,
10258 TREE_OPERAND (parm_max, 1));
10259 parm_max = TREE_OPERAND (parm_max, 0);
10262 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10265 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10266 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10273 case ENUMERAL_TYPE:
10275 if (TREE_CODE (arg) != TREE_CODE (parm))
10278 /* We have already checked cv-qualification at the top of the
10280 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10283 /* As far as unification is concerned, this wins. Later checks
10284 will invalidate it if necessary. */
10287 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10288 /* Type INTEGER_CST can come from ordinary constant template args. */
10290 while (TREE_CODE (arg) == NOP_EXPR)
10291 arg = TREE_OPERAND (arg, 0);
10293 if (TREE_CODE (arg) != INTEGER_CST)
10295 return !tree_int_cst_equal (parm, arg);
10300 if (TREE_CODE (arg) != TREE_VEC)
10302 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10304 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10305 if (unify (tparms, targs,
10306 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10314 if (TREE_CODE (arg) != TREE_CODE (parm))
10317 if (TYPE_PTRMEMFUNC_P (parm))
10319 if (!TYPE_PTRMEMFUNC_P (arg))
10322 return unify (tparms, targs,
10323 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10324 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10328 if (CLASSTYPE_TEMPLATE_INFO (parm))
10330 tree t = NULL_TREE;
10332 if (strict_in & UNIFY_ALLOW_DERIVED)
10334 /* First, we try to unify the PARM and ARG directly. */
10335 t = try_class_unification (tparms, targs,
10340 /* Fallback to the special case allowed in
10341 [temp.deduct.call]:
10343 If P is a class, and P has the form
10344 template-id, then A can be a derived class of
10345 the deduced A. Likewise, if P is a pointer to
10346 a class of the form template-id, A can be a
10347 pointer to a derived class pointed to by the
10349 t = get_template_base (tparms, targs, parm, arg);
10355 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10356 && (CLASSTYPE_TI_TEMPLATE (parm)
10357 == CLASSTYPE_TI_TEMPLATE (arg)))
10358 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10359 Then, we should unify `int' and `U'. */
10362 /* There's no chance of unification succeeding. */
10365 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10366 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10368 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10373 case FUNCTION_TYPE:
10374 if (TREE_CODE (arg) != TREE_CODE (parm))
10377 /* CV qualifications for methods can never be deduced, they must
10378 match exactly. We need to check them explicitly here,
10379 because type_unification_real treats them as any other
10380 cvqualified parameter. */
10381 if (TREE_CODE (parm) == METHOD_TYPE
10382 && (!check_cv_quals_for_unify
10384 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10385 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10388 if (unify (tparms, targs, TREE_TYPE (parm),
10389 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10391 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10392 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10396 /* Unify a pointer to member with a pointer to member function, which
10397 deduces the type of the member as a function type. */
10398 if (TYPE_PTRMEMFUNC_P (arg))
10402 cp_cv_quals cv_quals;
10404 /* Check top-level cv qualifiers */
10405 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10408 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10409 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10412 /* Determine the type of the function we are unifying against. */
10413 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10415 build_function_type (TREE_TYPE (method_type),
10416 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10418 /* Extract the cv-qualifiers of the member function from the
10419 implicit object parameter and place them on the function
10420 type to be restored later. */
10422 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10423 fntype = build_qualified_type (fntype, cv_quals);
10424 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10427 if (TREE_CODE (arg) != OFFSET_TYPE)
10429 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10430 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10432 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10436 if (DECL_TEMPLATE_PARM_P (parm))
10437 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10438 if (arg != integral_constant_value (parm))
10443 case TEMPLATE_DECL:
10444 /* Matched cases are handled by the ARG == PARM test above. */
10448 gcc_assert (EXPR_P (parm));
10450 /* We must be looking at an expression. This can happen with
10454 void foo(S<I>, S<I + 2>);
10456 This is a "nondeduced context":
10460 The nondeduced contexts are:
10462 --A type that is a template-id in which one or more of
10463 the template-arguments is an expression that references
10464 a template-parameter.
10466 In these cases, we assume deduction succeeded, but don't
10467 actually infer any unifications. */
10469 if (!uses_template_parms (parm)
10470 && !template_args_equal (parm, arg))
10477 /* Note that DECL can be defined in this translation unit, if
10481 mark_definable (tree decl)
10484 DECL_NOT_REALLY_EXTERN (decl) = 1;
10485 FOR_EACH_CLONE (clone, decl)
10486 DECL_NOT_REALLY_EXTERN (clone) = 1;
10489 /* Called if RESULT is explicitly instantiated, or is a member of an
10490 explicitly instantiated class. */
10493 mark_decl_instantiated (tree result, int extern_p)
10495 SET_DECL_EXPLICIT_INSTANTIATION (result);
10497 /* If this entity has already been written out, it's too late to
10498 make any modifications. */
10499 if (TREE_ASM_WRITTEN (result))
10502 if (TREE_CODE (result) != FUNCTION_DECL)
10503 /* The TREE_PUBLIC flag for function declarations will have been
10504 set correctly by tsubst. */
10505 TREE_PUBLIC (result) = 1;
10507 /* This might have been set by an earlier implicit instantiation. */
10508 DECL_COMDAT (result) = 0;
10511 DECL_NOT_REALLY_EXTERN (result) = 0;
10514 mark_definable (result);
10515 /* Always make artificials weak. */
10516 if (DECL_ARTIFICIAL (result) && flag_weak)
10517 comdat_linkage (result);
10518 /* For WIN32 we also want to put explicit instantiations in
10519 linkonce sections. */
10520 else if (TREE_PUBLIC (result))
10521 maybe_make_one_only (result);
10524 /* If EXTERN_P, then this function will not be emitted -- unless
10525 followed by an explicit instantiation, at which point its linkage
10526 will be adjusted. If !EXTERN_P, then this function will be
10527 emitted here. In neither circumstance do we want
10528 import_export_decl to adjust the linkage. */
10529 DECL_INTERFACE_KNOWN (result) = 1;
10532 /* Given two function templates PAT1 and PAT2, return:
10534 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10535 -1 if PAT2 is more specialized than PAT1.
10536 0 if neither is more specialized.
10538 LEN indicates the number of parameters we should consider
10539 (defaulted parameters should not be considered).
10541 The 1998 std underspecified function template partial ordering, and
10542 DR214 addresses the issue. We take pairs of arguments, one from
10543 each of the templates, and deduce them against each other. One of
10544 the templates will be more specialized if all the *other*
10545 template's arguments deduce against its arguments and at least one
10546 of its arguments *does* *not* deduce against the other template's
10547 corresponding argument. Deduction is done as for class templates.
10548 The arguments used in deduction have reference and top level cv
10549 qualifiers removed. Iff both arguments were originally reference
10550 types *and* deduction succeeds in both directions, the template
10551 with the more cv-qualified argument wins for that pairing (if
10552 neither is more cv-qualified, they both are equal). Unlike regular
10553 deduction, after all the arguments have been deduced in this way,
10554 we do *not* verify the deduced template argument values can be
10555 substituted into non-deduced contexts, nor do we have to verify
10556 that all template arguments have been deduced. */
10559 more_specialized_fn (tree pat1, tree pat2, int len)
10561 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10562 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10563 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10564 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10565 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10566 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10567 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10568 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10572 /* Remove the this parameter from non-static member functions. If
10573 one is a non-static member function and the other is not a static
10574 member function, remove the first parameter from that function
10575 also. This situation occurs for operator functions where we
10576 locate both a member function (with this pointer) and non-member
10577 operator (with explicit first operand). */
10578 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10580 len--; /* LEN is the number of significant arguments for DECL1 */
10581 args1 = TREE_CHAIN (args1);
10582 if (!DECL_STATIC_FUNCTION_P (decl2))
10583 args2 = TREE_CHAIN (args2);
10585 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10587 args2 = TREE_CHAIN (args2);
10588 if (!DECL_STATIC_FUNCTION_P (decl1))
10591 args1 = TREE_CHAIN (args1);
10595 /* If only one is a conversion operator, they are unordered. */
10596 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10599 /* Consider the return type for a conversion function */
10600 if (DECL_CONV_FN_P (decl1))
10602 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10603 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10607 processing_template_decl++;
10611 tree arg1 = TREE_VALUE (args1);
10612 tree arg2 = TREE_VALUE (args2);
10613 int deduce1, deduce2;
10617 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10619 arg1 = TREE_TYPE (arg1);
10620 quals1 = cp_type_quals (arg1);
10623 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10625 arg2 = TREE_TYPE (arg2);
10626 quals2 = cp_type_quals (arg2);
10629 if ((quals1 < 0) != (quals2 < 0))
10631 /* Only of the args is a reference, see if we should apply
10632 array/function pointer decay to it. This is not part of
10633 DR214, but is, IMHO, consistent with the deduction rules
10634 for the function call itself, and with our earlier
10635 implementation of the underspecified partial ordering
10636 rules. (nathan). */
10639 switch (TREE_CODE (arg1))
10642 arg1 = TREE_TYPE (arg1);
10644 case FUNCTION_TYPE:
10645 arg1 = build_pointer_type (arg1);
10654 switch (TREE_CODE (arg2))
10657 arg2 = TREE_TYPE (arg2);
10659 case FUNCTION_TYPE:
10660 arg2 = build_pointer_type (arg2);
10669 arg1 = TYPE_MAIN_VARIANT (arg1);
10670 arg2 = TYPE_MAIN_VARIANT (arg2);
10672 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10673 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10679 if (better1 < 0 && better2 < 0)
10680 /* We've failed to deduce something in either direction.
10681 These must be unordered. */
10684 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10686 /* Deduces in both directions, see if quals can
10687 disambiguate. Pretend the worse one failed to deduce. */
10688 if ((quals1 & quals2) == quals2)
10690 if ((quals1 & quals2) == quals1)
10693 if (deduce1 && !deduce2 && !better2)
10695 if (deduce2 && !deduce1 && !better1)
10698 args1 = TREE_CHAIN (args1);
10699 args2 = TREE_CHAIN (args2);
10702 processing_template_decl--;
10704 return (better1 > 0) - (better2 > 0);
10707 /* Determine which of two partial specializations is more specialized.
10709 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
10710 to the first partial specialization. The TREE_VALUE is the
10711 innermost set of template parameters for the partial
10712 specialization. PAT2 is similar, but for the second template.
10714 Return 1 if the first partial specialization is more specialized;
10715 -1 if the second is more specialized; 0 if neither is more
10718 See [temp.class.order] for information about determining which of
10719 two templates is more specialized. */
10722 more_specialized_class (tree pat1, tree pat2)
10728 tmpl1 = TREE_TYPE (pat1);
10729 tmpl2 = TREE_TYPE (pat2);
10731 /* Just like what happens for functions, if we are ordering between
10732 different class template specializations, we may encounter dependent
10733 types in the arguments, and we need our dependency check functions
10734 to behave correctly. */
10735 ++processing_template_decl;
10736 targs = get_class_bindings (TREE_VALUE (pat1),
10737 CLASSTYPE_TI_ARGS (tmpl1),
10738 CLASSTYPE_TI_ARGS (tmpl2));
10742 targs = get_class_bindings (TREE_VALUE (pat2),
10743 CLASSTYPE_TI_ARGS (tmpl2),
10744 CLASSTYPE_TI_ARGS (tmpl1));
10747 --processing_template_decl;
10752 /* Return the template arguments that will produce the function signature
10753 DECL from the function template FN, with the explicit template
10754 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10755 also match. Return NULL_TREE if no satisfactory arguments could be
10759 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10761 int ntparms = DECL_NTPARMS (fn);
10762 tree targs = make_tree_vec (ntparms);
10764 tree decl_arg_types;
10766 /* Substitute the explicit template arguments into the type of DECL.
10767 The call to fn_type_unification will handle substitution into the
10769 decl_type = TREE_TYPE (decl);
10770 if (explicit_args && uses_template_parms (decl_type))
10773 tree converted_args;
10775 if (DECL_TEMPLATE_INFO (decl))
10776 tmpl = DECL_TI_TEMPLATE (decl);
10778 /* We can get here for some invalid specializations. */
10782 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10783 explicit_args, NULL_TREE,
10784 tf_none, /*require_all_arguments=*/0));
10785 if (converted_args == error_mark_node)
10788 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10789 if (decl_type == error_mark_node)
10793 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10794 /* Never do unification on the 'this' parameter. */
10795 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10796 decl_arg_types = TREE_CHAIN (decl_arg_types);
10798 if (fn_type_unification (fn, explicit_args, targs,
10800 (check_rettype || DECL_CONV_FN_P (fn)
10801 ? TREE_TYPE (decl_type) : NULL_TREE),
10802 DEDUCE_EXACT, LOOKUP_NORMAL))
10808 /* Return the innermost template arguments that, when applied to a
10809 template specialization whose innermost template parameters are
10810 TPARMS, and whose specialization arguments are PARMS, yield the
10813 For example, suppose we have:
10815 template <class T, class U> struct S {};
10816 template <class T> struct S<T*, int> {};
10818 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10819 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
10820 int}. The resulting vector will be {double}, indicating that `T'
10821 is bound to `double'. */
10824 get_class_bindings (tree tparms, tree spec_args, tree args)
10826 int i, ntparms = TREE_VEC_LENGTH (tparms);
10828 tree innermost_deduced_args;
10830 innermost_deduced_args = make_tree_vec (ntparms);
10831 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
10833 deduced_args = copy_node (args);
10834 SET_TMPL_ARGS_LEVEL (deduced_args,
10835 TMPL_ARGS_DEPTH (deduced_args),
10836 innermost_deduced_args);
10839 deduced_args = innermost_deduced_args;
10841 if (unify (tparms, deduced_args,
10842 INNERMOST_TEMPLATE_ARGS (spec_args),
10843 INNERMOST_TEMPLATE_ARGS (args),
10847 for (i = 0; i < ntparms; ++i)
10848 if (! TREE_VEC_ELT (innermost_deduced_args, i))
10851 /* Verify that nondeduced template arguments agree with the type
10852 obtained from argument deduction.
10856 struct A { typedef int X; };
10857 template <class T, class U> struct C {};
10858 template <class T> struct C<T, typename T::X> {};
10860 Then with the instantiation `C<A, int>', we can deduce that
10861 `T' is `A' but unify () does not check whether `typename T::X'
10863 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
10864 if (spec_args == error_mark_node
10865 /* We only need to check the innermost arguments; the other
10866 arguments will always agree. */
10867 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
10868 INNERMOST_TEMPLATE_ARGS (args)))
10871 return deduced_args;
10874 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10875 Pick the most specialized template, and return the corresponding
10876 instantiation, or if there is no corresponding instantiation, the
10877 template itself. If there is no most specialized template,
10878 error_mark_node is returned. If there are no templates at all,
10879 NULL_TREE is returned. */
10882 most_specialized_instantiation (tree instantiations)
10886 if (!instantiations)
10889 ++processing_template_decl;
10891 champ = instantiations;
10892 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10896 if (get_bindings (TREE_VALUE (champ),
10897 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10898 NULL_TREE, /*check_ret=*/false))
10901 if (get_bindings (TREE_VALUE (fn),
10902 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10903 NULL_TREE, /*check_ret=*/false))
10910 /* Equally specialized, move to next function. If there
10911 is no next function, nothing's most specialized. */
10912 fn = TREE_CHAIN (fn);
10920 /* Now verify that champ is better than everything earlier in the
10921 instantiation list. */
10922 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10923 if (get_bindings (TREE_VALUE (champ),
10924 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10925 NULL_TREE, /*check_ret=*/false)
10926 || !get_bindings (TREE_VALUE (fn),
10927 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10928 NULL_TREE, /*check_ret=*/false))
10934 processing_template_decl--;
10937 return error_mark_node;
10939 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10942 /* Return the most specialized of the list of templates in FNS that can
10943 produce an instantiation matching DECL, given the explicit template
10944 arguments EXPLICIT_ARGS. */
10947 most_specialized (tree fns, tree decl, tree explicit_args)
10949 tree candidates = NULL_TREE;
10952 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10954 tree candidate = TREE_VALUE (fn);
10956 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10958 candidates = tree_cons (NULL_TREE, candidate, candidates);
10961 return most_specialized_instantiation (candidates);
10964 /* If DECL is a specialization of some template, return the most
10965 general such template. Otherwise, returns NULL_TREE.
10967 For example, given:
10969 template <class T> struct S { template <class U> void f(U); };
10971 if TMPL is `template <class U> void S<int>::f(U)' this will return
10972 the full template. This function will not trace past partial
10973 specializations, however. For example, given in addition:
10975 template <class T> struct S<T*> { template <class U> void f(U); };
10977 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10978 `template <class T> template <class U> S<T*>::f(U)'. */
10981 most_general_template (tree decl)
10983 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10984 an immediate specialization. */
10985 if (TREE_CODE (decl) == FUNCTION_DECL)
10987 if (DECL_TEMPLATE_INFO (decl)) {
10988 decl = DECL_TI_TEMPLATE (decl);
10990 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10991 template friend. */
10992 if (TREE_CODE (decl) != TEMPLATE_DECL)
10998 /* Look for more and more general templates. */
10999 while (DECL_TEMPLATE_INFO (decl))
11001 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
11002 (See cp-tree.h for details.) */
11003 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
11006 if (CLASS_TYPE_P (TREE_TYPE (decl))
11007 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
11010 /* Stop if we run into an explicitly specialized class template. */
11011 if (!DECL_NAMESPACE_SCOPE_P (decl)
11012 && DECL_CONTEXT (decl)
11013 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
11016 decl = DECL_TI_TEMPLATE (decl);
11022 /* Return the most specialized of the class template partial
11023 specializations of TMPL which can produce TYPE, a specialization of
11024 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
11025 a _TYPE node corresponding to the partial specialization, while the
11026 TREE_PURPOSE is the set of template arguments that must be
11027 substituted into the TREE_TYPE in order to generate TYPE.
11029 If the choice of partial specialization is ambiguous, a diagnostic
11030 is issued, and the error_mark_node is returned. If there are no
11031 partial specializations of TMPL matching TYPE, then NULL_TREE is
11035 most_specialized_class (tree type, tree tmpl)
11037 tree list = NULL_TREE;
11044 tmpl = most_general_template (tmpl);
11045 args = CLASSTYPE_TI_ARGS (type);
11046 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
11048 tree partial_spec_args;
11051 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
11052 spec_args = get_class_bindings (TREE_VALUE (t),
11057 list = tree_cons (spec_args, TREE_VALUE (t), list);
11058 TREE_TYPE (list) = TREE_TYPE (t);
11065 ambiguous_p = false;
11068 t = TREE_CHAIN (t);
11069 for (; t; t = TREE_CHAIN (t))
11071 fate = more_specialized_class (champ, t);
11078 t = TREE_CHAIN (t);
11081 ambiguous_p = true;
11090 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11092 fate = more_specialized_class (champ, t);
11095 ambiguous_p = true;
11102 const char *str = "candidates are:";
11103 error ("ambiguous class template instantiation for %q#T", type);
11104 for (t = list; t; t = TREE_CHAIN (t))
11106 error ("%s %+#T", str, TREE_TYPE (t));
11109 return error_mark_node;
11115 /* Explicitly instantiate DECL. */
11118 do_decl_instantiation (tree decl, tree storage)
11120 tree result = NULL_TREE;
11123 if (!decl || decl == error_mark_node)
11124 /* An error occurred, for which grokdeclarator has already issued
11125 an appropriate message. */
11127 else if (! DECL_LANG_SPECIFIC (decl))
11129 error ("explicit instantiation of non-template %q#D", decl);
11132 else if (TREE_CODE (decl) == VAR_DECL)
11134 /* There is an asymmetry here in the way VAR_DECLs and
11135 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11136 the latter, the DECL we get back will be marked as a
11137 template instantiation, and the appropriate
11138 DECL_TEMPLATE_INFO will be set up. This does not happen for
11139 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11140 should handle VAR_DECLs as it currently handles
11142 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11143 if (!result || TREE_CODE (result) != VAR_DECL)
11145 error ("no matching template for %qD found", decl);
11149 else if (TREE_CODE (decl) != FUNCTION_DECL)
11151 error ("explicit instantiation of %q#D", decl);
11157 /* Check for various error cases. Note that if the explicit
11158 instantiation is valid the RESULT will currently be marked as an
11159 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11160 until we get here. */
11162 if (DECL_TEMPLATE_SPECIALIZATION (result))
11164 /* DR 259 [temp.spec].
11166 Both an explicit instantiation and a declaration of an explicit
11167 specialization shall not appear in a program unless the explicit
11168 instantiation follows a declaration of the explicit specialization.
11170 For a given set of template parameters, if an explicit
11171 instantiation of a template appears after a declaration of an
11172 explicit specialization for that template, the explicit
11173 instantiation has no effect. */
11176 else if (DECL_EXPLICIT_INSTANTIATION (result))
11180 No program shall explicitly instantiate any template more
11183 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11184 the first instantiation was `extern' and the second is not,
11185 and EXTERN_P for the opposite case. */
11186 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11187 pedwarn ("duplicate explicit instantiation of %q#D", result);
11188 /* If an "extern" explicit instantiation follows an ordinary
11189 explicit instantiation, the template is instantiated. */
11193 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11195 error ("no matching template for %qD found", result);
11198 else if (!DECL_TEMPLATE_INFO (result))
11200 pedwarn ("explicit instantiation of non-template %q#D", result);
11204 if (storage == NULL_TREE)
11206 else if (storage == ridpointers[(int) RID_EXTERN])
11208 if (pedantic && !in_system_header)
11209 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11214 error ("storage class %qD applied to template instantiation", storage);
11216 check_explicit_instantiation_namespace (result);
11217 mark_decl_instantiated (result, extern_p);
11219 instantiate_decl (result, /*defer_ok=*/1,
11220 /*expl_inst_class_mem_p=*/false);
11224 mark_class_instantiated (tree t, int extern_p)
11226 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11227 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11228 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11229 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11232 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11233 rest_of_type_compilation (t, 1);
11237 /* Called from do_type_instantiation through binding_table_foreach to
11238 do recursive instantiation for the type bound in ENTRY. */
11240 bt_instantiate_type_proc (binding_entry entry, void *data)
11242 tree storage = *(tree *) data;
11244 if (IS_AGGR_TYPE (entry->type)
11245 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11246 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11249 /* Called from do_type_instantiation to instantiate a member
11250 (a member function or a static member variable) of an
11251 explicitly instantiated class template. */
11253 instantiate_class_member (tree decl, int extern_p)
11255 mark_decl_instantiated (decl, extern_p);
11257 instantiate_decl (decl, /*defer_ok=*/1,
11258 /*expl_inst_class_mem_p=*/true);
11261 /* Perform an explicit instantiation of template class T. STORAGE, if
11262 non-null, is the RID for extern, inline or static. COMPLAIN is
11263 nonzero if this is called from the parser, zero if called recursively,
11264 since the standard is unclear (as detailed below). */
11267 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11272 int previous_instantiation_extern_p = 0;
11274 if (TREE_CODE (t) == TYPE_DECL)
11277 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11279 error ("explicit instantiation of non-template type %qT", t);
11285 if (!COMPLETE_TYPE_P (t))
11287 if (complain & tf_error)
11288 error ("explicit instantiation of %q#T before definition of template",
11293 if (storage != NULL_TREE)
11295 if (pedantic && !in_system_header)
11296 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11299 if (storage == ridpointers[(int) RID_INLINE])
11301 else if (storage == ridpointers[(int) RID_EXTERN])
11303 else if (storage == ridpointers[(int) RID_STATIC])
11307 error ("storage class %qD applied to template instantiation",
11313 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11315 /* DR 259 [temp.spec].
11317 Both an explicit instantiation and a declaration of an explicit
11318 specialization shall not appear in a program unless the explicit
11319 instantiation follows a declaration of the explicit specialization.
11321 For a given set of template parameters, if an explicit
11322 instantiation of a template appears after a declaration of an
11323 explicit specialization for that template, the explicit
11324 instantiation has no effect. */
11327 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11331 No program shall explicitly instantiate any template more
11334 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11335 instantiation was `extern'. If EXTERN_P then the second is.
11336 These cases are OK. */
11337 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11339 if (!previous_instantiation_extern_p && !extern_p
11340 && (complain & tf_error))
11341 pedwarn ("duplicate explicit instantiation of %q#T", t);
11343 /* If we've already instantiated the template, just return now. */
11344 if (!CLASSTYPE_INTERFACE_ONLY (t))
11348 check_explicit_instantiation_namespace (TYPE_NAME (t));
11349 mark_class_instantiated (t, extern_p);
11357 /* In contrast to implicit instantiation, where only the
11358 declarations, and not the definitions, of members are
11359 instantiated, we have here:
11363 The explicit instantiation of a class template specialization
11364 implies the instantiation of all of its members not
11365 previously explicitly specialized in the translation unit
11366 containing the explicit instantiation.
11368 Of course, we can't instantiate member template classes, since
11369 we don't have any arguments for them. Note that the standard
11370 is unclear on whether the instantiation of the members are
11371 *explicit* instantiations or not. However, the most natural
11372 interpretation is that it should be an explicit instantiation. */
11375 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11376 if (TREE_CODE (tmp) == FUNCTION_DECL
11377 && DECL_TEMPLATE_INSTANTIATION (tmp))
11378 instantiate_class_member (tmp, extern_p);
11380 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11381 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11382 instantiate_class_member (tmp, extern_p);
11384 if (CLASSTYPE_NESTED_UTDS (t))
11385 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11386 bt_instantiate_type_proc, &storage);
11390 /* Given a function DECL, which is a specialization of TMPL, modify
11391 DECL to be a re-instantiation of TMPL with the same template
11392 arguments. TMPL should be the template into which tsubst'ing
11393 should occur for DECL, not the most general template.
11395 One reason for doing this is a scenario like this:
11398 void f(const T&, int i);
11400 void g() { f(3, 7); }
11403 void f(const T& t, const int i) { }
11405 Note that when the template is first instantiated, with
11406 instantiate_template, the resulting DECL will have no name for the
11407 first parameter, and the wrong type for the second. So, when we go
11408 to instantiate the DECL, we regenerate it. */
11411 regenerate_decl_from_template (tree decl, tree tmpl)
11413 /* The arguments used to instantiate DECL, from the most general
11418 args = DECL_TI_ARGS (decl);
11419 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11421 /* Make sure that we can see identifiers, and compute access
11423 push_access_scope (decl);
11425 if (TREE_CODE (decl) == FUNCTION_DECL)
11433 args_depth = TMPL_ARGS_DEPTH (args);
11434 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11435 if (args_depth > parms_depth)
11436 args = get_innermost_template_args (args, parms_depth);
11438 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11439 args, tf_error, NULL_TREE);
11441 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11444 /* Merge parameter declarations. */
11445 decl_parm = skip_artificial_parms_for (decl,
11446 DECL_ARGUMENTS (decl));
11448 = skip_artificial_parms_for (code_pattern,
11449 DECL_ARGUMENTS (code_pattern));
11455 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11456 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11457 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11459 parm_type = type_decays_to (parm_type);
11460 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11461 TREE_TYPE (decl_parm) = parm_type;
11462 attributes = DECL_ATTRIBUTES (pattern_parm);
11463 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11465 DECL_ATTRIBUTES (decl_parm) = attributes;
11466 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11468 decl_parm = TREE_CHAIN (decl_parm);
11469 pattern_parm = TREE_CHAIN (pattern_parm);
11472 /* Merge additional specifiers from the CODE_PATTERN. */
11473 if (DECL_DECLARED_INLINE_P (code_pattern)
11474 && !DECL_DECLARED_INLINE_P (decl))
11475 DECL_DECLARED_INLINE_P (decl) = 1;
11476 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11477 DECL_INLINE (decl) = 1;
11479 else if (TREE_CODE (decl) == VAR_DECL)
11480 DECL_INITIAL (decl) =
11481 tsubst_expr (DECL_INITIAL (code_pattern), args,
11482 tf_error, DECL_TI_TEMPLATE (decl));
11484 gcc_unreachable ();
11486 pop_access_scope (decl);
11489 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11490 substituted to get DECL. */
11493 template_for_substitution (tree decl)
11495 tree tmpl = DECL_TI_TEMPLATE (decl);
11497 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11498 for the instantiation. This is not always the most general
11499 template. Consider, for example:
11502 struct S { template <class U> void f();
11503 template <> void f<int>(); };
11505 and an instantiation of S<double>::f<int>. We want TD to be the
11506 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11507 while (/* An instantiation cannot have a definition, so we need a
11508 more general template. */
11509 DECL_TEMPLATE_INSTANTIATION (tmpl)
11510 /* We must also deal with friend templates. Given:
11512 template <class T> struct S {
11513 template <class U> friend void f() {};
11516 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11517 so far as the language is concerned, but that's still
11518 where we get the pattern for the instantiation from. On
11519 other hand, if the definition comes outside the class, say:
11521 template <class T> struct S {
11522 template <class U> friend void f();
11524 template <class U> friend void f() {}
11526 we don't need to look any further. That's what the check for
11527 DECL_INITIAL is for. */
11528 || (TREE_CODE (decl) == FUNCTION_DECL
11529 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11530 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11532 /* The present template, TD, should not be a definition. If it
11533 were a definition, we should be using it! Note that we
11534 cannot restructure the loop to just keep going until we find
11535 a template with a definition, since that might go too far if
11536 a specialization was declared, but not defined. */
11537 gcc_assert (TREE_CODE (decl) != VAR_DECL
11538 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11540 /* Fetch the more general template. */
11541 tmpl = DECL_TI_TEMPLATE (tmpl);
11547 /* Produce the definition of D, a _DECL generated from a template. If
11548 DEFER_OK is nonzero, then we don't have to actually do the
11549 instantiation now; we just have to do it sometime. Normally it is
11550 an error if this is an explicit instantiation but D is undefined.
11551 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11552 explicitly instantiated class template. */
11555 instantiate_decl (tree d, int defer_ok,
11556 bool expl_inst_class_mem_p)
11558 tree tmpl = DECL_TI_TEMPLATE (d);
11565 bool pattern_defined;
11567 location_t saved_loc = input_location;
11570 /* This function should only be used to instantiate templates for
11571 functions and static member variables. */
11572 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11573 || TREE_CODE (d) == VAR_DECL);
11575 /* Variables are never deferred; if instantiation is required, they
11576 are instantiated right away. That allows for better code in the
11577 case that an expression refers to the value of the variable --
11578 if the variable has a constant value the referring expression can
11579 take advantage of that fact. */
11580 if (TREE_CODE (d) == VAR_DECL)
11583 /* Don't instantiate cloned functions. Instead, instantiate the
11584 functions they cloned. */
11585 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11586 d = DECL_CLONED_FUNCTION (d);
11588 if (DECL_TEMPLATE_INSTANTIATED (d))
11589 /* D has already been instantiated. It might seem reasonable to
11590 check whether or not D is an explicit instantiation, and, if so,
11591 stop here. But when an explicit instantiation is deferred
11592 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11593 is set, even though we still need to do the instantiation. */
11596 /* If we already have a specialization of this declaration, then
11597 there's no reason to instantiate it. Note that
11598 retrieve_specialization gives us both instantiations and
11599 specializations, so we must explicitly check
11600 DECL_TEMPLATE_SPECIALIZATION. */
11601 gen_tmpl = most_general_template (tmpl);
11602 gen_args = DECL_TI_ARGS (d);
11603 spec = retrieve_specialization (gen_tmpl, gen_args,
11604 /*class_specializations_p=*/false);
11605 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11608 /* This needs to happen before any tsubsting. */
11609 if (! push_tinst_level (d))
11612 timevar_push (TV_PARSE);
11614 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11615 for the instantiation. */
11616 td = template_for_substitution (d);
11617 code_pattern = DECL_TEMPLATE_RESULT (td);
11619 /* We should never be trying to instantiate a member of a class
11620 template or partial specialization. */
11621 gcc_assert (d != code_pattern);
11623 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11624 || DECL_TEMPLATE_SPECIALIZATION (td))
11625 /* In the case of a friend template whose definition is provided
11626 outside the class, we may have too many arguments. Drop the
11627 ones we don't need. The same is true for specializations. */
11628 args = get_innermost_template_args
11629 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11633 if (TREE_CODE (d) == FUNCTION_DECL)
11634 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11636 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11638 /* We may be in the middle of deferred access check. Disable it now. */
11639 push_deferring_access_checks (dk_no_deferred);
11641 /* Unless an explicit instantiation directive has already determined
11642 the linkage of D, remember that a definition is available for
11644 if (pattern_defined
11645 && !DECL_INTERFACE_KNOWN (d)
11646 && !DECL_NOT_REALLY_EXTERN (d))
11647 mark_definable (d);
11649 input_location = DECL_SOURCE_LOCATION (d);
11651 /* If D is a member of an explicitly instantiated class template,
11652 and no definition is available, treat it like an implicit
11654 if (!pattern_defined && expl_inst_class_mem_p
11655 && DECL_EXPLICIT_INSTANTIATION (d))
11657 DECL_NOT_REALLY_EXTERN (d) = 0;
11658 DECL_INTERFACE_KNOWN (d) = 0;
11659 SET_DECL_IMPLICIT_INSTANTIATION (d);
11664 /* Recheck the substitutions to obtain any warning messages
11665 about ignoring cv qualifiers. */
11666 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11667 tree type = TREE_TYPE (gen);
11669 /* Make sure that we can see identifiers, and compute access
11670 correctly. D is already the target FUNCTION_DECL with the
11672 push_access_scope (d);
11674 if (TREE_CODE (gen) == FUNCTION_DECL)
11676 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11677 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11678 tf_error | tf_warning, d);
11679 /* Don't simply tsubst the function type, as that will give
11680 duplicate warnings about poor parameter qualifications.
11681 The function arguments are the same as the decl_arguments
11682 without the top level cv qualifiers. */
11683 type = TREE_TYPE (type);
11685 tsubst (type, gen_args, tf_error | tf_warning, d);
11687 pop_access_scope (d);
11690 /* Check to see whether we know that this template will be
11691 instantiated in some other file, as with "extern template"
11693 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11694 /* In general, we do not instantiate such templates... */
11696 /* ... but we instantiate inline functions so that we can inline
11698 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11699 /* ... we instantiate static data members whose values are
11700 needed in integral constant expressions. */
11701 && ! (TREE_CODE (d) == VAR_DECL
11702 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11704 /* Defer all other templates, unless we have been explicitly
11705 forbidden from doing so. */
11706 if (/* If there is no definition, we cannot instantiate the
11709 /* If it's OK to postpone instantiation, do so. */
11711 /* If this is a static data member that will be defined
11712 elsewhere, we don't want to instantiate the entire data
11713 member, but we do want to instantiate the initializer so that
11714 we can substitute that elsewhere. */
11715 || (external_p && TREE_CODE (d) == VAR_DECL))
11717 /* The definition of the static data member is now required so
11718 we must substitute the initializer. */
11719 if (TREE_CODE (d) == VAR_DECL
11720 && !DECL_INITIAL (d)
11721 && DECL_INITIAL (code_pattern))
11726 ns = decl_namespace_context (d);
11727 push_nested_namespace (ns);
11728 push_nested_class (DECL_CONTEXT (d));
11729 init = tsubst_expr (DECL_INITIAL (code_pattern),
11731 tf_error | tf_warning, NULL_TREE);
11732 DECL_INITIAL (d) = init;
11733 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
11734 /*asmspec_tree=*/NULL_TREE,
11735 LOOKUP_ONLYCONVERTING);
11736 pop_nested_class ();
11737 pop_nested_namespace (ns);
11740 /* We restore the source position here because it's used by
11741 add_pending_template. */
11742 input_location = saved_loc;
11744 if (at_eof && !pattern_defined
11745 && DECL_EXPLICIT_INSTANTIATION (d))
11748 The definition of a non-exported function template, a
11749 non-exported member function template, or a non-exported
11750 member function or static data member of a class template
11751 shall be present in every translation unit in which it is
11752 explicitly instantiated. */
11754 ("explicit instantiation of %qD but no definition available", d);
11756 /* ??? Historically, we have instantiated inline functions, even
11757 when marked as "extern template". */
11758 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11759 add_pending_template (d);
11762 /* Tell the repository that D is available in this translation unit
11763 -- and see if it is supposed to be instantiated here. */
11764 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11766 /* In a PCH file, despite the fact that the repository hasn't
11767 requested instantiation in the PCH it is still possible that
11768 an instantiation will be required in a file that includes the
11771 add_pending_template (d);
11772 /* Instantiate inline functions so that the inliner can do its
11773 job, even though we'll not be emitting a copy of this
11775 if (!(TREE_CODE (d) == FUNCTION_DECL
11776 && flag_inline_trees
11777 && DECL_DECLARED_INLINE_P (d)))
11781 need_push = !cfun || !global_bindings_p ();
11783 push_to_top_level ();
11785 /* Mark D as instantiated so that recursive calls to
11786 instantiate_decl do not try to instantiate it again. */
11787 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11789 /* Regenerate the declaration in case the template has been modified
11790 by a subsequent redeclaration. */
11791 regenerate_decl_from_template (d, td);
11793 /* We already set the file and line above. Reset them now in case
11794 they changed as a result of calling regenerate_decl_from_template. */
11795 input_location = DECL_SOURCE_LOCATION (d);
11797 if (TREE_CODE (d) == VAR_DECL)
11799 /* Clear out DECL_RTL; whatever was there before may not be right
11800 since we've reset the type of the declaration. */
11801 SET_DECL_RTL (d, NULL_RTX);
11802 DECL_IN_AGGR_P (d) = 0;
11804 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11805 initializer. That function will defer actual emission until
11806 we have a chance to determine linkage. */
11807 DECL_EXTERNAL (d) = 0;
11809 /* Enter the scope of D so that access-checking works correctly. */
11810 push_nested_class (DECL_CONTEXT (d));
11811 finish_decl (d, DECL_INITIAL (d), NULL_TREE);
11812 pop_nested_class ();
11814 else if (TREE_CODE (d) == FUNCTION_DECL)
11816 htab_t saved_local_specializations;
11821 /* Save away the current list, in case we are instantiating one
11822 template from within the body of another. */
11823 saved_local_specializations = local_specializations;
11825 /* Set up the list of local specializations. */
11826 local_specializations = htab_create (37,
11827 hash_local_specialization,
11828 eq_local_specializations,
11831 /* Set up context. */
11832 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11834 /* Create substitution entries for the parameters. */
11835 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11836 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11837 spec_parm = DECL_ARGUMENTS (d);
11838 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11840 register_local_specialization (spec_parm, tmpl_parm);
11841 spec_parm = skip_artificial_parms_for (d, spec_parm);
11842 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11846 register_local_specialization (spec_parm, tmpl_parm);
11847 tmpl_parm = TREE_CHAIN (tmpl_parm);
11848 spec_parm = TREE_CHAIN (spec_parm);
11850 gcc_assert (!spec_parm);
11852 /* Substitute into the body of the function. */
11853 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11854 tf_error | tf_warning, tmpl);
11856 /* We don't need the local specializations any more. */
11857 htab_delete (local_specializations);
11858 local_specializations = saved_local_specializations;
11860 /* Finish the function. */
11861 d = finish_function (0);
11862 expand_or_defer_fn (d);
11865 /* We're not deferring instantiation any more. */
11866 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11869 pop_from_top_level ();
11872 input_location = saved_loc;
11873 pop_deferring_access_checks ();
11874 pop_tinst_level ();
11876 timevar_pop (TV_PARSE);
11881 /* Run through the list of templates that we wish we could
11882 instantiate, and instantiate any we can. RETRIES is the
11883 number of times we retry pending template instantiation. */
11886 instantiate_pending_templates (int retries)
11889 tree last = NULL_TREE;
11891 location_t saved_loc = input_location;
11892 int saved_in_system_header = in_system_header;
11894 /* Instantiating templates may trigger vtable generation. This in turn
11895 may require further template instantiations. We place a limit here
11896 to avoid infinite loop. */
11897 if (pending_templates && retries >= max_tinst_depth)
11899 tree decl = TREE_VALUE (pending_templates);
11901 error ("template instantiation depth exceeds maximum of %d"
11902 " instantiating %q+D, possibly from virtual table generation"
11903 " (use -ftemplate-depth-NN to increase the maximum)",
11904 max_tinst_depth, decl);
11905 if (TREE_CODE (decl) == FUNCTION_DECL)
11906 /* Pretend that we defined it. */
11907 DECL_INITIAL (decl) = error_mark_node;
11915 t = &pending_templates;
11918 tree instantiation = TREE_VALUE (*t);
11920 reopen_tinst_level (TREE_PURPOSE (*t));
11922 if (TYPE_P (instantiation))
11926 if (!COMPLETE_TYPE_P (instantiation))
11928 instantiate_class_template (instantiation);
11929 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11930 for (fn = TYPE_METHODS (instantiation);
11932 fn = TREE_CHAIN (fn))
11933 if (! DECL_ARTIFICIAL (fn))
11934 instantiate_decl (fn,
11936 /*expl_inst_class_mem_p=*/false);
11937 if (COMPLETE_TYPE_P (instantiation))
11941 if (COMPLETE_TYPE_P (instantiation))
11942 /* If INSTANTIATION has been instantiated, then we don't
11943 need to consider it again in the future. */
11944 *t = TREE_CHAIN (*t);
11948 t = &TREE_CHAIN (*t);
11953 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11954 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11957 = instantiate_decl (instantiation,
11959 /*expl_inst_class_mem_p=*/false);
11960 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11964 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11965 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11966 /* If INSTANTIATION has been instantiated, then we don't
11967 need to consider it again in the future. */
11968 *t = TREE_CHAIN (*t);
11972 t = &TREE_CHAIN (*t);
11976 current_tinst_level = NULL_TREE;
11978 last_pending_template = last;
11980 while (reconsider);
11982 input_location = saved_loc;
11983 in_system_header = saved_in_system_header;
11986 /* Substitute ARGVEC into T, which is a list of initializers for
11987 either base class or a non-static data member. The TREE_PURPOSEs
11988 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11989 instantiate_decl. */
11992 tsubst_initializer_list (tree t, tree argvec)
11994 tree inits = NULL_TREE;
11996 for (; t; t = TREE_CHAIN (t))
12001 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
12003 decl = expand_member_init (decl);
12004 if (decl && !DECL_P (decl))
12005 in_base_initializer = 1;
12007 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
12009 in_base_initializer = 0;
12013 init = build_tree_list (decl, init);
12014 TREE_CHAIN (init) = inits;
12021 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
12024 set_current_access_from_decl (tree decl)
12026 if (TREE_PRIVATE (decl))
12027 current_access_specifier = access_private_node;
12028 else if (TREE_PROTECTED (decl))
12029 current_access_specifier = access_protected_node;
12031 current_access_specifier = access_public_node;
12034 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
12035 is the instantiation (which should have been created with
12036 start_enum) and ARGS are the template arguments to use. */
12039 tsubst_enum (tree tag, tree newtag, tree args)
12043 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
12048 decl = TREE_VALUE (e);
12049 /* Note that in a template enum, the TREE_VALUE is the
12050 CONST_DECL, not the corresponding INTEGER_CST. */
12051 value = tsubst_expr (DECL_INITIAL (decl),
12052 args, tf_error | tf_warning,
12055 /* Give this enumeration constant the correct access. */
12056 set_current_access_from_decl (decl);
12058 /* Actually build the enumerator itself. */
12059 build_enumerator (DECL_NAME (decl), value, newtag);
12062 finish_enum (newtag);
12063 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
12064 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
12067 /* DECL is a FUNCTION_DECL that is a template specialization. Return
12068 its type -- but without substituting the innermost set of template
12069 arguments. So, innermost set of template parameters will appear in
12073 get_mostly_instantiated_function_type (tree decl)
12081 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
12082 targs = DECL_TI_ARGS (decl);
12083 tparms = DECL_TEMPLATE_PARMS (tmpl);
12084 parm_depth = TMPL_PARMS_DEPTH (tparms);
12086 /* There should be as many levels of arguments as there are levels
12088 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
12090 fn_type = TREE_TYPE (tmpl);
12092 if (parm_depth == 1)
12093 /* No substitution is necessary. */
12097 int i, save_access_control;
12100 /* Replace the innermost level of the TARGS with NULL_TREEs to
12101 let tsubst know not to substitute for those parameters. */
12102 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
12103 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
12104 SET_TMPL_ARGS_LEVEL (partial_args, i,
12105 TMPL_ARGS_LEVEL (targs, i));
12106 SET_TMPL_ARGS_LEVEL (partial_args,
12107 TMPL_ARGS_DEPTH (targs),
12108 make_tree_vec (DECL_NTPARMS (tmpl)));
12110 /* Disable access control as this function is used only during
12112 save_access_control = flag_access_control;
12113 flag_access_control = 0;
12115 ++processing_template_decl;
12116 /* Now, do the (partial) substitution to figure out the
12117 appropriate function type. */
12118 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12119 --processing_template_decl;
12121 /* Substitute into the template parameters to obtain the real
12122 innermost set of parameters. This step is important if the
12123 innermost set of template parameters contains value
12124 parameters whose types depend on outer template parameters. */
12125 TREE_VEC_LENGTH (partial_args)--;
12126 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12128 flag_access_control = save_access_control;
12134 /* Return truthvalue if we're processing a template different from
12135 the last one involved in diagnostics. */
12137 problematic_instantiation_changed (void)
12139 return last_template_error_tick != tinst_level_tick;
12142 /* Remember current template involved in diagnostics. */
12144 record_last_problematic_instantiation (void)
12146 last_template_error_tick = tinst_level_tick;
12150 current_instantiation (void)
12152 return current_tinst_level;
12155 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12156 type. Return zero for ok, nonzero for disallowed. Issue error and
12157 warning messages under control of COMPLAIN. */
12160 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12162 if (INTEGRAL_TYPE_P (type))
12164 else if (POINTER_TYPE_P (type))
12166 else if (TYPE_PTR_TO_MEMBER_P (type))
12168 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12170 else if (TREE_CODE (type) == TYPENAME_TYPE)
12173 if (complain & tf_error)
12174 error ("%q#T is not a valid type for a template constant parameter", type);
12178 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12179 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12182 dependent_type_p_r (tree type)
12188 A type is dependent if it is:
12190 -- a template parameter. Template template parameters are types
12191 for us (since TYPE_P holds true for them) so we handle
12193 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12194 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12196 /* -- a qualified-id with a nested-name-specifier which contains a
12197 class-name that names a dependent type or whose unqualified-id
12198 names a dependent type. */
12199 if (TREE_CODE (type) == TYPENAME_TYPE)
12201 /* -- a cv-qualified type where the cv-unqualified type is
12203 type = TYPE_MAIN_VARIANT (type);
12204 /* -- a compound type constructed from any dependent type. */
12205 if (TYPE_PTR_TO_MEMBER_P (type))
12206 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12207 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12209 else if (TREE_CODE (type) == POINTER_TYPE
12210 || TREE_CODE (type) == REFERENCE_TYPE)
12211 return dependent_type_p (TREE_TYPE (type));
12212 else if (TREE_CODE (type) == FUNCTION_TYPE
12213 || TREE_CODE (type) == METHOD_TYPE)
12217 if (dependent_type_p (TREE_TYPE (type)))
12219 for (arg_type = TYPE_ARG_TYPES (type);
12221 arg_type = TREE_CHAIN (arg_type))
12222 if (dependent_type_p (TREE_VALUE (arg_type)))
12226 /* -- an array type constructed from any dependent type or whose
12227 size is specified by a constant expression that is
12228 value-dependent. */
12229 if (TREE_CODE (type) == ARRAY_TYPE)
12231 if (TYPE_DOMAIN (type)
12232 && ((value_dependent_expression_p
12233 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12234 || (type_dependent_expression_p
12235 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12237 return dependent_type_p (TREE_TYPE (type));
12240 /* -- a template-id in which either the template name is a template
12242 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12244 /* ... or any of the template arguments is a dependent type or
12245 an expression that is type-dependent or value-dependent. */
12246 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12247 && (any_dependent_template_arguments_p
12248 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12251 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12252 expression is not type-dependent, then it should already been
12254 if (TREE_CODE (type) == TYPEOF_TYPE)
12257 /* The standard does not specifically mention types that are local
12258 to template functions or local classes, but they should be
12259 considered dependent too. For example:
12261 template <int I> void f() {
12266 The size of `E' cannot be known until the value of `I' has been
12267 determined. Therefore, `E' must be considered dependent. */
12268 scope = TYPE_CONTEXT (type);
12269 if (scope && TYPE_P (scope))
12270 return dependent_type_p (scope);
12271 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12272 return type_dependent_expression_p (scope);
12274 /* Other types are non-dependent. */
12278 /* Returns TRUE if TYPE is dependent, in the sense of
12279 [temp.dep.type]. */
12282 dependent_type_p (tree type)
12284 /* If there are no template parameters in scope, then there can't be
12285 any dependent types. */
12286 if (!processing_template_decl)
12289 /* If the type is NULL, we have not computed a type for the entity
12290 in question; in that case, the type is dependent. */
12294 /* Erroneous types can be considered non-dependent. */
12295 if (type == error_mark_node)
12298 /* If we have not already computed the appropriate value for TYPE,
12300 if (!TYPE_DEPENDENT_P_VALID (type))
12302 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12303 TYPE_DEPENDENT_P_VALID (type) = 1;
12306 return TYPE_DEPENDENT_P (type);
12309 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12312 dependent_scope_ref_p (tree expression, bool criterion (tree))
12317 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12319 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12322 scope = TREE_OPERAND (expression, 0);
12323 name = TREE_OPERAND (expression, 1);
12327 An id-expression is type-dependent if it contains a
12328 nested-name-specifier that contains a class-name that names a
12330 /* The suggested resolution to Core Issue 2 implies that if the
12331 qualifying type is the current class, then we must peek
12334 && currently_open_class (scope)
12335 && !criterion (name))
12337 if (dependent_type_p (scope))
12343 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12344 [temp.dep.constexpr] */
12347 value_dependent_expression_p (tree expression)
12349 if (!processing_template_decl)
12352 /* A name declared with a dependent type. */
12353 if (DECL_P (expression) && type_dependent_expression_p (expression))
12356 switch (TREE_CODE (expression))
12358 case IDENTIFIER_NODE:
12359 /* A name that has not been looked up -- must be dependent. */
12362 case TEMPLATE_PARM_INDEX:
12363 /* A non-type template parm. */
12367 /* A non-type template parm. */
12368 if (DECL_TEMPLATE_PARM_P (expression))
12373 /* A constant with integral or enumeration type and is initialized
12374 with an expression that is value-dependent. */
12375 if (DECL_INITIAL (expression)
12376 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12377 && value_dependent_expression_p (DECL_INITIAL (expression)))
12381 case DYNAMIC_CAST_EXPR:
12382 case STATIC_CAST_EXPR:
12383 case CONST_CAST_EXPR:
12384 case REINTERPRET_CAST_EXPR:
12386 /* These expressions are value-dependent if the type to which
12387 the cast occurs is dependent or the expression being casted
12388 is value-dependent. */
12390 tree type = TREE_TYPE (expression);
12392 if (dependent_type_p (type))
12395 /* A functional cast has a list of operands. */
12396 expression = TREE_OPERAND (expression, 0);
12399 /* If there are no operands, it must be an expression such
12400 as "int()". This should not happen for aggregate types
12401 because it would form non-constant expressions. */
12402 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12407 if (TREE_CODE (expression) == TREE_LIST)
12409 for (; expression; expression = TREE_CHAIN (expression))
12410 if (value_dependent_expression_p (TREE_VALUE (expression)))
12415 return value_dependent_expression_p (expression);
12420 /* A `sizeof' expression is value-dependent if the operand is
12422 expression = TREE_OPERAND (expression, 0);
12423 if (TYPE_P (expression))
12424 return dependent_type_p (expression);
12425 return type_dependent_expression_p (expression);
12428 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12430 case COMPONENT_REF:
12431 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12432 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12435 /* A CALL_EXPR is value-dependent if any argument is
12436 value-dependent. Why do we have to handle CALL_EXPRs in this
12437 function at all? First, some function calls, those for which
12438 value_dependent_expression_p is true, man appear in constant
12439 expressions. Second, there appear to be bugs which result in
12440 other CALL_EXPRs reaching this point. */
12442 tree function = TREE_OPERAND (expression, 0);
12443 tree args = TREE_OPERAND (expression, 1);
12445 if (value_dependent_expression_p (function))
12451 if (TREE_CODE (args) == TREE_LIST)
12453 for (; args; args = TREE_CHAIN (args))
12454 if (value_dependent_expression_p (TREE_VALUE (args)))
12459 return value_dependent_expression_p (args);
12463 /* A constant expression is value-dependent if any subexpression is
12464 value-dependent. */
12465 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12467 case tcc_reference:
12469 return (value_dependent_expression_p
12470 (TREE_OPERAND (expression, 0)));
12472 case tcc_comparison:
12474 return ((value_dependent_expression_p
12475 (TREE_OPERAND (expression, 0)))
12476 || (value_dependent_expression_p
12477 (TREE_OPERAND (expression, 1))));
12479 case tcc_expression:
12482 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12483 /* In some cases, some of the operands may be missing.
12484 (For example, in the case of PREDECREMENT_EXPR, the
12485 amount to increment by may be missing.) That doesn't
12486 make the expression dependent. */
12487 if (TREE_OPERAND (expression, i)
12488 && (value_dependent_expression_p
12489 (TREE_OPERAND (expression, i))))
12499 /* The expression is not value-dependent. */
12503 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12504 [temp.dep.expr]. */
12507 type_dependent_expression_p (tree expression)
12509 if (!processing_template_decl)
12512 if (expression == error_mark_node)
12515 /* An unresolved name is always dependent. */
12516 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12519 /* Some expression forms are never type-dependent. */
12520 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12521 || TREE_CODE (expression) == SIZEOF_EXPR
12522 || TREE_CODE (expression) == ALIGNOF_EXPR
12523 || TREE_CODE (expression) == TYPEID_EXPR
12524 || TREE_CODE (expression) == DELETE_EXPR
12525 || TREE_CODE (expression) == VEC_DELETE_EXPR
12526 || TREE_CODE (expression) == THROW_EXPR)
12529 /* The types of these expressions depends only on the type to which
12530 the cast occurs. */
12531 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12532 || TREE_CODE (expression) == STATIC_CAST_EXPR
12533 || TREE_CODE (expression) == CONST_CAST_EXPR
12534 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12535 || TREE_CODE (expression) == CAST_EXPR)
12536 return dependent_type_p (TREE_TYPE (expression));
12538 /* The types of these expressions depends only on the type created
12539 by the expression. */
12540 if (TREE_CODE (expression) == NEW_EXPR
12541 || TREE_CODE (expression) == VEC_NEW_EXPR)
12543 /* For NEW_EXPR tree nodes created inside a template, either
12544 the object type itself or a TREE_LIST may appear as the
12546 tree type = TREE_OPERAND (expression, 1);
12547 if (TREE_CODE (type) == TREE_LIST)
12548 /* This is an array type. We need to check array dimensions
12550 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12551 || value_dependent_expression_p
12552 (TREE_OPERAND (TREE_VALUE (type), 1));
12554 return dependent_type_p (type);
12557 if (TREE_CODE (expression) == SCOPE_REF
12558 && dependent_scope_ref_p (expression,
12559 type_dependent_expression_p))
12562 if (TREE_CODE (expression) == FUNCTION_DECL
12563 && DECL_LANG_SPECIFIC (expression)
12564 && DECL_TEMPLATE_INFO (expression)
12565 && (any_dependent_template_arguments_p
12566 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12569 if (TREE_CODE (expression) == TEMPLATE_DECL
12570 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12573 if (TREE_TYPE (expression) == unknown_type_node)
12575 if (TREE_CODE (expression) == ADDR_EXPR)
12576 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12577 if (TREE_CODE (expression) == COMPONENT_REF
12578 || TREE_CODE (expression) == OFFSET_REF)
12580 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12582 expression = TREE_OPERAND (expression, 1);
12583 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12586 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12587 if (TREE_CODE (expression) == SCOPE_REF)
12590 if (TREE_CODE (expression) == BASELINK)
12591 expression = BASELINK_FUNCTIONS (expression);
12593 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12595 if (any_dependent_template_arguments_p
12596 (TREE_OPERAND (expression, 1)))
12598 expression = TREE_OPERAND (expression, 0);
12600 gcc_assert (TREE_CODE (expression) == OVERLOAD
12601 || TREE_CODE (expression) == FUNCTION_DECL);
12605 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12607 expression = OVL_NEXT (expression);
12612 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12614 return (dependent_type_p (TREE_TYPE (expression)));
12617 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12618 contains a type-dependent expression. */
12621 any_type_dependent_arguments_p (tree args)
12625 tree arg = TREE_VALUE (args);
12627 if (type_dependent_expression_p (arg))
12629 args = TREE_CHAIN (args);
12634 /* Returns TRUE if the ARG (a template argument) is dependent. */
12637 dependent_template_arg_p (tree arg)
12639 if (!processing_template_decl)
12642 if (TREE_CODE (arg) == TEMPLATE_DECL
12643 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12644 return dependent_template_p (arg);
12645 else if (TYPE_P (arg))
12646 return dependent_type_p (arg);
12648 return (type_dependent_expression_p (arg)
12649 || value_dependent_expression_p (arg));
12652 /* Returns true if ARGS (a collection of template arguments) contains
12653 any dependent arguments. */
12656 any_dependent_template_arguments_p (tree args)
12663 if (args == error_mark_node)
12666 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12668 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12669 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12670 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12677 /* Returns TRUE if the template TMPL is dependent. */
12680 dependent_template_p (tree tmpl)
12682 if (TREE_CODE (tmpl) == OVERLOAD)
12686 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12688 tmpl = OVL_CHAIN (tmpl);
12693 /* Template template parameters are dependent. */
12694 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12695 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12697 /* So are names that have not been looked up. */
12698 if (TREE_CODE (tmpl) == SCOPE_REF
12699 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12701 /* So are member templates of dependent classes. */
12702 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12703 return dependent_type_p (DECL_CONTEXT (tmpl));
12707 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12710 dependent_template_id_p (tree tmpl, tree args)
12712 return (dependent_template_p (tmpl)
12713 || any_dependent_template_arguments_p (args));
12716 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12717 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12718 can be found. Note that this function peers inside uninstantiated
12719 templates and therefore should be used only in extremely limited
12720 situations. ONLY_CURRENT_P restricts this peering to the currently
12721 open classes hierarchy (which is required when comparing types). */
12724 resolve_typename_type (tree type, bool only_current_p)
12732 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12734 scope = TYPE_CONTEXT (type);
12735 name = TYPE_IDENTIFIER (type);
12737 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12738 it first before we can figure out what NAME refers to. */
12739 if (TREE_CODE (scope) == TYPENAME_TYPE)
12740 scope = resolve_typename_type (scope, only_current_p);
12741 /* If we don't know what SCOPE refers to, then we cannot resolve the
12743 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12744 return error_mark_node;
12745 /* If the SCOPE is a template type parameter, we have no way of
12746 resolving the name. */
12747 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12749 /* If the SCOPE is not the current instantiation, there's no reason
12750 to look inside it. */
12751 if (only_current_p && !currently_open_class (scope))
12752 return error_mark_node;
12753 /* If SCOPE is a partial instantiation, it will not have a valid
12754 TYPE_FIELDS list, so use the original template. */
12755 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12756 /* Enter the SCOPE so that name lookup will be resolved as if we
12757 were in the class definition. In particular, SCOPE will no
12758 longer be considered a dependent type. */
12759 pushed_scope = push_scope (scope);
12760 /* Look up the declaration. */
12761 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12762 /* Obtain the set of qualifiers applied to the TYPE. */
12763 quals = cp_type_quals (type);
12764 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12765 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12767 type = error_mark_node;
12768 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12769 && TREE_CODE (decl) == TYPE_DECL)
12770 type = TREE_TYPE (decl);
12771 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12772 && DECL_CLASS_TEMPLATE_P (decl))
12776 /* Obtain the template and the arguments. */
12777 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12778 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12779 /* Instantiate the template. */
12780 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12781 /*entering_scope=*/0, tf_error | tf_user);
12784 type = error_mark_node;
12785 /* Qualify the resulting type. */
12786 if (type != error_mark_node && quals)
12787 type = cp_build_qualified_type (type, quals);
12788 /* Leave the SCOPE. */
12790 pop_scope (pushed_scope);
12795 /* EXPR is an expression which is not type-dependent. Return a proxy
12796 for EXPR that can be used to compute the types of larger
12797 expressions containing EXPR. */
12800 build_non_dependent_expr (tree expr)
12804 /* Preserve null pointer constants so that the type of things like
12805 "p == 0" where "p" is a pointer can be determined. */
12806 if (null_ptr_cst_p (expr))
12808 /* Preserve OVERLOADs; the functions must be available to resolve
12810 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12811 TREE_OPERAND (expr, 0) :
12812 TREE_CODE (expr) == COMPONENT_REF ?
12813 TREE_OPERAND (expr, 1) : expr);
12814 if (is_overloaded_fn (inner_expr)
12815 || TREE_CODE (inner_expr) == OFFSET_REF)
12817 /* There is no need to return a proxy for a variable. */
12818 if (TREE_CODE (expr) == VAR_DECL)
12820 /* Preserve string constants; conversions from string constants to
12821 "char *" are allowed, even though normally a "const char *"
12822 cannot be used to initialize a "char *". */
12823 if (TREE_CODE (expr) == STRING_CST)
12825 /* Preserve arithmetic constants, as an optimization -- there is no
12826 reason to create a new node. */
12827 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12829 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12830 There is at least one place where we want to know that a
12831 particular expression is a throw-expression: when checking a ?:
12832 expression, there are special rules if the second or third
12833 argument is a throw-expression. */
12834 if (TREE_CODE (expr) == THROW_EXPR)
12837 if (TREE_CODE (expr) == COND_EXPR)
12838 return build3 (COND_EXPR,
12840 TREE_OPERAND (expr, 0),
12841 (TREE_OPERAND (expr, 1)
12842 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12843 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12844 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12845 if (TREE_CODE (expr) == COMPOUND_EXPR
12846 && !COMPOUND_EXPR_OVERLOADED (expr))
12847 return build2 (COMPOUND_EXPR,
12849 TREE_OPERAND (expr, 0),
12850 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12852 /* If the type is unknown, it can't really be non-dependent */
12853 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
12855 /* Otherwise, build a NON_DEPENDENT_EXPR.
12857 REFERENCE_TYPEs are not stripped for expressions in templates
12858 because doing so would play havoc with mangling. Consider, for
12861 template <typename T> void f<T& g>() { g(); }
12863 In the body of "f", the expression for "g" will have
12864 REFERENCE_TYPE, even though the standard says that it should
12865 not. The reason is that we must preserve the syntactic form of
12866 the expression so that mangling (say) "f<g>" inside the body of
12867 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12869 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12872 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12873 Return a new TREE_LIST with the various arguments replaced with
12874 equivalent non-dependent expressions. */
12877 build_non_dependent_args (tree args)
12882 new_args = NULL_TREE;
12883 for (a = args; a; a = TREE_CHAIN (a))
12884 new_args = tree_cons (NULL_TREE,
12885 build_non_dependent_expr (TREE_VALUE (a)),
12887 return nreverse (new_args);
12890 #include "gt-cp-pt.h"