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, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
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"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #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 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 static void push_access_scope (tree);
113 static void pop_access_scope (tree);
114 static void push_deduction_access_scope (tree);
115 static void pop_deduction_access_scope (tree);
116 static bool resolve_overloaded_unification (tree, tree, tree, tree,
117 unification_kind_t, int);
118 static int try_one_overload (tree, tree, tree, tree, tree,
119 unification_kind_t, int, bool);
120 static int unify (tree, tree, tree, tree, int);
121 static void add_pending_template (tree);
122 static tree reopen_tinst_level (struct tinst_level *);
123 static tree tsubst_initializer_list (tree, tree);
124 static tree get_class_bindings (tree, tree, tree);
125 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
127 static void tsubst_enum (tree, tree, tree);
128 static tree add_to_template_args (tree, tree);
129 static tree add_outermost_template_args (tree, tree);
130 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
131 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
133 static int type_unification_real (tree, tree, tree, const tree *,
134 unsigned int, int, unification_kind_t, int);
135 static void note_template_header (int);
136 static tree convert_nontype_argument_function (tree, tree);
137 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
138 static tree convert_template_argument (tree, tree, tree,
139 tsubst_flags_t, int, tree);
140 static int for_each_template_parm (tree, tree_fn_t, void*,
141 struct pointer_set_t*, bool);
142 static tree expand_template_argument_pack (tree);
143 static tree build_template_parm_index (int, int, int, int, tree, tree);
144 static bool inline_needs_template_parms (tree);
145 static void push_inline_template_parms_recursive (tree, int);
146 static tree retrieve_local_specialization (tree);
147 static void register_local_specialization (tree, tree);
148 static hashval_t hash_specialization (const void *p);
149 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
150 static int mark_template_parm (tree, void *);
151 static int template_parm_this_level_p (tree, void *);
152 static tree tsubst_friend_function (tree, tree);
153 static tree tsubst_friend_class (tree, tree);
154 static int can_complete_type_without_circularity (tree);
155 static tree get_bindings (tree, tree, tree, bool);
156 static int template_decl_level (tree);
157 static int check_cv_quals_for_unify (int, tree, tree);
158 static void template_parm_level_and_index (tree, int*, int*);
159 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
160 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
161 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
163 static void regenerate_decl_from_template (tree, tree);
164 static tree most_specialized_class (tree, tree, tsubst_flags_t);
165 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
166 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
167 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
168 static bool check_specialization_scope (void);
169 static tree process_partial_specialization (tree);
170 static void set_current_access_from_decl (tree);
171 static tree get_template_base (tree, tree, tree, tree);
172 static tree try_class_unification (tree, tree, tree, tree);
173 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
175 static bool template_template_parm_bindings_ok_p (tree, tree);
176 static int template_args_equal (tree, tree);
177 static void tsubst_default_arguments (tree);
178 static tree for_each_template_parm_r (tree *, int *, void *);
179 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
180 static void copy_default_args_to_explicit_spec (tree);
181 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
182 static int eq_local_specializations (const void *, const void *);
183 static bool dependent_template_arg_p (tree);
184 static bool any_template_arguments_need_structural_equality_p (tree);
185 static bool dependent_type_p_r (tree);
186 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
187 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
188 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_decl (tree, tree, tsubst_flags_t);
190 static void perform_typedefs_access_check (tree tmpl, tree targs);
191 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
193 static tree listify (tree);
194 static tree listify_autos (tree, tree);
195 static tree template_parm_to_arg (tree t);
196 static tree current_template_args (void);
197 static tree fixup_template_type_parm_type (tree, int);
198 static tree fixup_template_parm_index (tree, tree, int);
199 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
201 /* Make the current scope suitable for access checking when we are
202 processing T. T can be FUNCTION_DECL for instantiated function
203 template, or VAR_DECL for static member variable (need by
204 instantiate_decl). */
207 push_access_scope (tree t)
209 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
210 || TREE_CODE (t) == VAR_DECL);
212 if (DECL_FRIEND_CONTEXT (t))
213 push_nested_class (DECL_FRIEND_CONTEXT (t));
214 else if (DECL_CLASS_SCOPE_P (t))
215 push_nested_class (DECL_CONTEXT (t));
217 pushclass (NULL_TREE);
219 if (TREE_CODE (t) == FUNCTION_DECL)
221 saved_access_scope = tree_cons
222 (NULL_TREE, current_function_decl, saved_access_scope);
223 current_function_decl = t;
227 /* Restore the scope set up by push_access_scope. T is the node we
231 pop_access_scope (tree t)
233 if (TREE_CODE (t) == FUNCTION_DECL)
235 current_function_decl = TREE_VALUE (saved_access_scope);
236 saved_access_scope = TREE_CHAIN (saved_access_scope);
239 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
245 /* Do any processing required when DECL (a member template
246 declaration) is finished. Returns the TEMPLATE_DECL corresponding
247 to DECL, unless it is a specialization, in which case the DECL
248 itself is returned. */
251 finish_member_template_decl (tree decl)
253 if (decl == error_mark_node)
254 return error_mark_node;
256 gcc_assert (DECL_P (decl));
258 if (TREE_CODE (decl) == TYPE_DECL)
262 type = TREE_TYPE (decl);
263 if (type == error_mark_node)
264 return error_mark_node;
265 if (MAYBE_CLASS_TYPE_P (type)
266 && CLASSTYPE_TEMPLATE_INFO (type)
267 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
269 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
270 check_member_template (tmpl);
275 else if (TREE_CODE (decl) == FIELD_DECL)
276 error ("data member %qD cannot be a member template", decl);
277 else if (DECL_TEMPLATE_INFO (decl))
279 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
281 check_member_template (DECL_TI_TEMPLATE (decl));
282 return DECL_TI_TEMPLATE (decl);
288 error ("invalid member template declaration %qD", decl);
290 return error_mark_node;
293 /* Create a template info node. */
296 build_template_info (tree template_decl, tree template_args)
298 tree result = make_node (TEMPLATE_INFO);
299 TI_TEMPLATE (result) = template_decl;
300 TI_ARGS (result) = template_args;
304 /* Return the template info node corresponding to T, whatever T is. */
307 get_template_info (const_tree t)
309 tree tinfo = NULL_TREE;
311 if (!t || t == error_mark_node)
314 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
315 tinfo = DECL_TEMPLATE_INFO (t);
317 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
320 if (TAGGED_TYPE_P (t))
321 tinfo = TYPE_TEMPLATE_INFO (t);
322 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
323 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
328 /* Returns the template nesting level of the indicated class TYPE.
338 A<T>::B<U> has depth two, while A<T> has depth one.
339 Both A<T>::B<int> and A<int>::B<U> have depth one, if
340 they are instantiations, not specializations.
342 This function is guaranteed to return 0 if passed NULL_TREE so
343 that, for example, `template_class_depth (current_class_type)' is
347 template_class_depth (tree type)
352 type && TREE_CODE (type) != NAMESPACE_DECL;
353 type = (TREE_CODE (type) == FUNCTION_DECL)
354 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
356 tree tinfo = get_template_info (type);
358 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
359 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
366 /* Subroutine of maybe_begin_member_template_processing.
367 Returns true if processing DECL needs us to push template parms. */
370 inline_needs_template_parms (tree decl)
372 if (! DECL_TEMPLATE_INFO (decl))
375 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
376 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
379 /* Subroutine of maybe_begin_member_template_processing.
380 Push the template parms in PARMS, starting from LEVELS steps into the
381 chain, and ending at the beginning, since template parms are listed
385 push_inline_template_parms_recursive (tree parmlist, int levels)
387 tree parms = TREE_VALUE (parmlist);
391 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
393 ++processing_template_decl;
394 current_template_parms
395 = tree_cons (size_int (processing_template_decl),
396 parms, current_template_parms);
397 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
399 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
401 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
403 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
405 if (parm == error_mark_node)
408 gcc_assert (DECL_P (parm));
410 switch (TREE_CODE (parm))
419 /* Make a CONST_DECL as is done in process_template_parm.
420 It is ugly that we recreate this here; the original
421 version built in process_template_parm is no longer
423 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
424 CONST_DECL, DECL_NAME (parm),
426 DECL_ARTIFICIAL (decl) = 1;
427 TREE_CONSTANT (decl) = 1;
428 TREE_READONLY (decl) = 1;
429 DECL_INITIAL (decl) = DECL_INITIAL (parm);
430 SET_DECL_TEMPLATE_PARM_P (decl);
441 /* Restore the template parameter context for a member template or
442 a friend template defined in a class definition. */
445 maybe_begin_member_template_processing (tree decl)
450 if (inline_needs_template_parms (decl))
452 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
453 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
455 if (DECL_TEMPLATE_SPECIALIZATION (decl))
458 parms = TREE_CHAIN (parms);
461 push_inline_template_parms_recursive (parms, levels);
464 /* Remember how many levels of template parameters we pushed so that
465 we can pop them later. */
466 VEC_safe_push (int, heap, inline_parm_levels, levels);
469 /* Undo the effects of maybe_begin_member_template_processing. */
472 maybe_end_member_template_processing (void)
477 if (VEC_length (int, inline_parm_levels) == 0)
480 last = VEC_pop (int, inline_parm_levels);
481 for (i = 0; i < last; ++i)
483 --processing_template_decl;
484 current_template_parms = TREE_CHAIN (current_template_parms);
489 /* Return a new template argument vector which contains all of ARGS,
490 but has as its innermost set of arguments the EXTRA_ARGS. */
493 add_to_template_args (tree args, tree extra_args)
500 if (args == NULL_TREE || extra_args == error_mark_node)
503 extra_depth = TMPL_ARGS_DEPTH (extra_args);
504 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
506 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
507 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
509 for (j = 1; j <= extra_depth; ++j, ++i)
510 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
515 /* Like add_to_template_args, but only the outermost ARGS are added to
516 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
517 (EXTRA_ARGS) levels are added. This function is used to combine
518 the template arguments from a partial instantiation with the
519 template arguments used to attain the full instantiation from the
520 partial instantiation. */
523 add_outermost_template_args (tree args, tree extra_args)
527 /* If there are more levels of EXTRA_ARGS than there are ARGS,
528 something very fishy is going on. */
529 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
531 /* If *all* the new arguments will be the EXTRA_ARGS, just return
533 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
536 /* For the moment, we make ARGS look like it contains fewer levels. */
537 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
539 new_args = add_to_template_args (args, extra_args);
541 /* Now, we restore ARGS to its full dimensions. */
542 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
547 /* Return the N levels of innermost template arguments from the ARGS. */
550 get_innermost_template_args (tree args, int n)
558 /* If N is 1, just return the innermost set of template arguments. */
560 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
562 /* If we're not removing anything, just return the arguments we were
564 extra_levels = TMPL_ARGS_DEPTH (args) - n;
565 gcc_assert (extra_levels >= 0);
566 if (extra_levels == 0)
569 /* Make a new set of arguments, not containing the outer arguments. */
570 new_args = make_tree_vec (n);
571 for (i = 1; i <= n; ++i)
572 SET_TMPL_ARGS_LEVEL (new_args, i,
573 TMPL_ARGS_LEVEL (args, i + extra_levels));
578 /* The inverse of get_innermost_template_args: Return all but the innermost
579 EXTRA_LEVELS levels of template arguments from the ARGS. */
582 strip_innermost_template_args (tree args, int extra_levels)
585 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
590 /* If N is 1, just return the outermost set of template arguments. */
592 return TMPL_ARGS_LEVEL (args, 1);
594 /* If we're not removing anything, just return the arguments we were
596 gcc_assert (extra_levels >= 0);
597 if (extra_levels == 0)
600 /* Make a new set of arguments, not containing the inner arguments. */
601 new_args = make_tree_vec (n);
602 for (i = 1; i <= n; ++i)
603 SET_TMPL_ARGS_LEVEL (new_args, i,
604 TMPL_ARGS_LEVEL (args, i));
609 /* We've got a template header coming up; push to a new level for storing
613 begin_template_parm_list (void)
615 /* We use a non-tag-transparent scope here, which causes pushtag to
616 put tags in this scope, rather than in the enclosing class or
617 namespace scope. This is the right thing, since we want
618 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
619 global template class, push_template_decl handles putting the
620 TEMPLATE_DECL into top-level scope. For a nested template class,
623 template <class T> struct S1 {
624 template <class T> struct S2 {};
627 pushtag contains special code to call pushdecl_with_scope on the
628 TEMPLATE_DECL for S2. */
629 begin_scope (sk_template_parms, NULL);
630 ++processing_template_decl;
631 ++processing_template_parmlist;
632 note_template_header (0);
635 /* This routine is called when a specialization is declared. If it is
636 invalid to declare a specialization here, an error is reported and
637 false is returned, otherwise this routine will return true. */
640 check_specialization_scope (void)
642 tree scope = current_scope ();
646 An explicit specialization shall be declared in the namespace of
647 which the template is a member, or, for member templates, in the
648 namespace of which the enclosing class or enclosing class
649 template is a member. An explicit specialization of a member
650 function, member class or static data member of a class template
651 shall be declared in the namespace of which the class template
653 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
655 error ("explicit specialization in non-namespace scope %qD", scope);
661 In an explicit specialization declaration for a member of a class
662 template or a member template that appears in namespace scope,
663 the member template and some of its enclosing class templates may
664 remain unspecialized, except that the declaration shall not
665 explicitly specialize a class member template if its enclosing
666 class templates are not explicitly specialized as well. */
667 if (current_template_parms)
669 error ("enclosing class templates are not explicitly specialized");
676 /* We've just seen template <>. */
679 begin_specialization (void)
681 begin_scope (sk_template_spec, NULL);
682 note_template_header (1);
683 return check_specialization_scope ();
686 /* Called at then end of processing a declaration preceded by
690 end_specialization (void)
693 reset_specialization ();
696 /* Any template <>'s that we have seen thus far are not referring to a
697 function specialization. */
700 reset_specialization (void)
702 processing_specialization = 0;
703 template_header_count = 0;
706 /* We've just seen a template header. If SPECIALIZATION is nonzero,
707 it was of the form template <>. */
710 note_template_header (int specialization)
712 processing_specialization = specialization;
713 template_header_count++;
716 /* We're beginning an explicit instantiation. */
719 begin_explicit_instantiation (void)
721 gcc_assert (!processing_explicit_instantiation);
722 processing_explicit_instantiation = true;
727 end_explicit_instantiation (void)
729 gcc_assert (processing_explicit_instantiation);
730 processing_explicit_instantiation = false;
733 /* An explicit specialization or partial specialization TMPL is being
734 declared. Check that the namespace in which the specialization is
735 occurring is permissible. Returns false iff it is invalid to
736 specialize TMPL in the current namespace. */
739 check_specialization_namespace (tree tmpl)
741 tree tpl_ns = decl_namespace_context (tmpl);
745 An explicit specialization shall be declared in the namespace of
746 which the template is a member, or, for member templates, in the
747 namespace of which the enclosing class or enclosing class
748 template is a member. An explicit specialization of a member
749 function, member class or static data member of a class template
750 shall be declared in the namespace of which the class template is
752 if (current_scope() != DECL_CONTEXT (tmpl)
753 && !at_namespace_scope_p ())
755 error ("specialization of %qD must appear at namespace scope", tmpl);
758 if (is_associated_namespace (current_namespace, tpl_ns))
759 /* Same or super-using namespace. */
763 permerror (input_location, "specialization of %qD in different namespace", tmpl);
764 permerror (input_location, " from definition of %q+#D", tmpl);
769 /* SPEC is an explicit instantiation. Check that it is valid to
770 perform this explicit instantiation in the current namespace. */
773 check_explicit_instantiation_namespace (tree spec)
777 /* DR 275: An explicit instantiation shall appear in an enclosing
778 namespace of its template. */
779 ns = decl_namespace_context (spec);
780 if (!is_ancestor (current_namespace, ns))
781 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
782 "(which does not enclose namespace %qD)",
783 spec, current_namespace, ns);
786 /* The TYPE is being declared. If it is a template type, that means it
787 is a partial specialization. Do appropriate error-checking. */
790 maybe_process_partial_specialization (tree type)
794 if (type == error_mark_node)
795 return error_mark_node;
797 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
799 error ("name of class shadows template template parameter %qD",
801 return error_mark_node;
804 context = TYPE_CONTEXT (type);
806 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
808 /* This is for ordinary explicit specialization and partial
809 specialization of a template class such as:
811 template <> class C<int>;
815 template <class T> class C<T*>;
817 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
819 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
820 && !COMPLETE_TYPE_P (type))
822 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
823 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
824 if (processing_template_decl)
826 if (push_template_decl (TYPE_MAIN_DECL (type))
828 return error_mark_node;
831 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
832 error ("specialization of %qT after instantiation", type);
834 else if (CLASS_TYPE_P (type)
835 && !CLASSTYPE_USE_TEMPLATE (type)
836 && CLASSTYPE_TEMPLATE_INFO (type)
837 && context && CLASS_TYPE_P (context)
838 && CLASSTYPE_TEMPLATE_INFO (context))
840 /* This is for an explicit specialization of member class
841 template according to [temp.expl.spec/18]:
843 template <> template <class U> class C<int>::D;
845 The context `C<int>' must be an implicit instantiation.
846 Otherwise this is just a member class template declared
849 template <> class C<int> { template <class U> class D; };
850 template <> template <class U> class C<int>::D;
852 In the first case, `C<int>::D' is a specialization of `C<T>::D'
853 while in the second case, `C<int>::D' is a primary template
854 and `C<T>::D' may not exist. */
856 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
857 && !COMPLETE_TYPE_P (type))
860 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
862 if (current_namespace
863 != decl_namespace_context (tmpl))
865 permerror (input_location, "specializing %q#T in different namespace", type);
866 permerror (input_location, " from definition of %q+#D", tmpl);
869 /* Check for invalid specialization after instantiation:
871 template <> template <> class C<int>::D<int>;
872 template <> template <class U> class C<int>::D; */
874 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
875 t; t = TREE_CHAIN (t))
877 tree inst = TREE_VALUE (t);
878 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
880 /* We already have a full specialization of this partial
881 instantiation. Reassign it to the new member
882 specialization template. */
886 elt.tmpl = most_general_template (tmpl);
887 elt.args = CLASSTYPE_TI_ARGS (inst);
890 htab_remove_elt (type_specializations, &elt);
893 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
895 slot = (spec_entry **)
896 htab_find_slot (type_specializations, &elt, INSERT);
897 *slot = ggc_alloc_spec_entry ();
900 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
901 /* But if we've had an implicit instantiation, that's a
902 problem ([temp.expl.spec]/6). */
903 error ("specialization %qT after instantiation %qT",
907 /* Mark TYPE as a specialization. And as a result, we only
908 have one level of template argument for the innermost
910 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
911 CLASSTYPE_TI_ARGS (type)
912 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
915 else if (processing_specialization)
917 /* Someday C++0x may allow for enum template specialization. */
918 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
919 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
920 pedwarn (input_location, OPT_pedantic, "template specialization "
921 "of %qD not allowed by ISO C++", type);
924 error ("explicit specialization of non-template %qT", type);
925 return error_mark_node;
932 /* Returns nonzero if we can optimize the retrieval of specializations
933 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
934 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
937 optimize_specialization_lookup_p (tree tmpl)
939 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
940 && DECL_CLASS_SCOPE_P (tmpl)
941 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
943 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
944 /* The optimized lookup depends on the fact that the
945 template arguments for the member function template apply
946 purely to the containing class, which is not true if the
947 containing class is an explicit or partial
949 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
950 && !DECL_MEMBER_TEMPLATE_P (tmpl)
951 && !DECL_CONV_FN_P (tmpl)
952 /* It is possible to have a template that is not a member
953 template and is not a member of a template class:
955 template <typename T>
956 struct S { friend A::f(); };
958 Here, the friend function is a template, but the context does
959 not have template information. The optimized lookup relies
960 on having ARGS be the template arguments for both the class
961 and the function template. */
962 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
965 /* Retrieve the specialization (in the sense of [temp.spec] - a
966 specialization is either an instantiation or an explicit
967 specialization) of TMPL for the given template ARGS. If there is
968 no such specialization, return NULL_TREE. The ARGS are a vector of
969 arguments, or a vector of vectors of arguments, in the case of
970 templates with more than one level of parameters.
972 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
973 then we search for a partial specialization matching ARGS. This
974 parameter is ignored if TMPL is not a class template. */
977 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
979 if (args == error_mark_node)
982 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
984 /* There should be as many levels of arguments as there are
985 levels of parameters. */
986 gcc_assert (TMPL_ARGS_DEPTH (args)
987 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
989 if (optimize_specialization_lookup_p (tmpl))
992 tree class_specialization;
993 VEC(tree,gc) *methods;
997 /* The template arguments actually apply to the containing
998 class. Find the class specialization with those
1000 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1001 class_specialization
1002 = retrieve_specialization (class_template, args, 0);
1003 if (!class_specialization)
1005 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1006 for the specialization. */
1007 idx = class_method_index_for_fn (class_specialization, tmpl);
1010 /* Iterate through the methods with the indicated name, looking
1011 for the one that has an instance of TMPL. */
1012 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1013 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1015 tree fn = OVL_CURRENT (fns);
1016 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1017 /* using-declarations can add base methods to the method vec,
1018 and we don't want those here. */
1019 && DECL_CONTEXT (fn) == class_specialization)
1028 htab_t specializations;
1032 elt.spec = NULL_TREE;
1034 if (DECL_CLASS_TEMPLATE_P (tmpl))
1035 specializations = type_specializations;
1037 specializations = decl_specializations;
1040 hash = hash_specialization (&elt);
1041 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1049 /* Like retrieve_specialization, but for local declarations. */
1052 retrieve_local_specialization (tree tmpl)
1056 if (local_specializations == NULL)
1059 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1060 htab_hash_pointer (tmpl));
1061 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1064 /* Returns nonzero iff DECL is a specialization of TMPL. */
1067 is_specialization_of (tree decl, tree tmpl)
1071 if (TREE_CODE (decl) == FUNCTION_DECL)
1075 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1081 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1083 for (t = TREE_TYPE (decl);
1085 t = CLASSTYPE_USE_TEMPLATE (t)
1086 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1087 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1094 /* Returns nonzero iff DECL is a specialization of friend declaration
1095 FRIEND_DECL according to [temp.friend]. */
1098 is_specialization_of_friend (tree decl, tree friend_decl)
1100 bool need_template = true;
1103 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1104 || TREE_CODE (decl) == TYPE_DECL);
1106 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1107 of a template class, we want to check if DECL is a specialization
1109 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1110 && DECL_TEMPLATE_INFO (friend_decl)
1111 && !DECL_USE_TEMPLATE (friend_decl))
1113 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1114 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1115 need_template = false;
1117 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1118 && !PRIMARY_TEMPLATE_P (friend_decl))
1119 need_template = false;
1121 /* There is nothing to do if this is not a template friend. */
1122 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1125 if (is_specialization_of (decl, friend_decl))
1129 A member of a class template may be declared to be a friend of a
1130 non-template class. In this case, the corresponding member of
1131 every specialization of the class template is a friend of the
1132 class granting friendship.
1134 For example, given a template friend declaration
1136 template <class T> friend void A<T>::f();
1138 the member function below is considered a friend
1140 template <> struct A<int> {
1144 For this type of template friend, TEMPLATE_DEPTH below will be
1145 nonzero. To determine if DECL is a friend of FRIEND, we first
1146 check if the enclosing class is a specialization of another. */
1148 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1150 && DECL_CLASS_SCOPE_P (decl)
1151 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1152 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1154 /* Next, we check the members themselves. In order to handle
1155 a few tricky cases, such as when FRIEND_DECL's are
1157 template <class T> friend void A<T>::g(T t);
1158 template <class T> template <T t> friend void A<T>::h();
1162 void A<int>::g(int);
1163 template <int> void A<int>::h();
1165 we need to figure out ARGS, the template arguments from
1166 the context of DECL. This is required for template substitution
1167 of `T' in the function parameter of `g' and template parameter
1168 of `h' in the above examples. Here ARGS corresponds to `int'. */
1170 tree context = DECL_CONTEXT (decl);
1171 tree args = NULL_TREE;
1172 int current_depth = 0;
1174 while (current_depth < template_depth)
1176 if (CLASSTYPE_TEMPLATE_INFO (context))
1178 if (current_depth == 0)
1179 args = TYPE_TI_ARGS (context);
1181 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1184 context = TYPE_CONTEXT (context);
1187 if (TREE_CODE (decl) == FUNCTION_DECL)
1192 tree friend_args_type;
1193 tree decl_args_type;
1195 /* Make sure that both DECL and FRIEND_DECL are templates or
1197 is_template = DECL_TEMPLATE_INFO (decl)
1198 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1199 if (need_template ^ is_template)
1201 else if (is_template)
1203 /* If both are templates, check template parameter list. */
1205 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1207 if (!comp_template_parms
1208 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1212 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1215 decl_type = TREE_TYPE (decl);
1217 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1218 tf_none, NULL_TREE);
1219 if (friend_type == error_mark_node)
1222 /* Check if return types match. */
1223 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1226 /* Check if function parameter types match, ignoring the
1227 `this' parameter. */
1228 friend_args_type = TYPE_ARG_TYPES (friend_type);
1229 decl_args_type = TYPE_ARG_TYPES (decl_type);
1230 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1231 friend_args_type = TREE_CHAIN (friend_args_type);
1232 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1233 decl_args_type = TREE_CHAIN (decl_args_type);
1235 return compparms (decl_args_type, friend_args_type);
1239 /* DECL is a TYPE_DECL */
1241 tree decl_type = TREE_TYPE (decl);
1243 /* Make sure that both DECL and FRIEND_DECL are templates or
1246 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1247 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1249 if (need_template ^ is_template)
1251 else if (is_template)
1254 /* If both are templates, check the name of the two
1255 TEMPLATE_DECL's first because is_friend didn't. */
1256 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1257 != DECL_NAME (friend_decl))
1260 /* Now check template parameter list. */
1262 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1264 return comp_template_parms
1265 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1269 return (DECL_NAME (decl)
1270 == DECL_NAME (friend_decl));
1276 /* Register the specialization SPEC as a specialization of TMPL with
1277 the indicated ARGS. IS_FRIEND indicates whether the specialization
1278 is actually just a friend declaration. Returns SPEC, or an
1279 equivalent prior declaration, if available. */
1282 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1286 spec_entry **slot = NULL;
1289 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1291 if (TREE_CODE (spec) == FUNCTION_DECL
1292 && uses_template_parms (DECL_TI_ARGS (spec)))
1293 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1294 register it; we want the corresponding TEMPLATE_DECL instead.
1295 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1296 the more obvious `uses_template_parms (spec)' to avoid problems
1297 with default function arguments. In particular, given
1298 something like this:
1300 template <class T> void f(T t1, T t = T())
1302 the default argument expression is not substituted for in an
1303 instantiation unless and until it is actually needed. */
1306 if (optimize_specialization_lookup_p (tmpl))
1307 /* We don't put these specializations in the hash table, but we might
1308 want to give an error about a mismatch. */
1309 fn = retrieve_specialization (tmpl, args, 0);
1317 hash = hash_specialization (&elt);
1319 slot = (spec_entry **)
1320 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1327 /* We can sometimes try to re-register a specialization that we've
1328 already got. In particular, regenerate_decl_from_template calls
1329 duplicate_decls which will update the specialization list. But,
1330 we'll still get called again here anyhow. It's more convenient
1331 to simply allow this than to try to prevent it. */
1334 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1336 if (DECL_TEMPLATE_INSTANTIATION (fn))
1338 if (DECL_ODR_USED (fn)
1339 || DECL_EXPLICIT_INSTANTIATION (fn))
1341 error ("specialization of %qD after instantiation",
1343 return error_mark_node;
1348 /* This situation should occur only if the first
1349 specialization is an implicit instantiation, the
1350 second is an explicit specialization, and the
1351 implicit instantiation has not yet been used. That
1352 situation can occur if we have implicitly
1353 instantiated a member function and then specialized
1356 We can also wind up here if a friend declaration that
1357 looked like an instantiation turns out to be a
1360 template <class T> void foo(T);
1361 class S { friend void foo<>(int) };
1362 template <> void foo(int);
1364 We transform the existing DECL in place so that any
1365 pointers to it become pointers to the updated
1368 If there was a definition for the template, but not
1369 for the specialization, we want this to look as if
1370 there were no definition, and vice versa. */
1371 DECL_INITIAL (fn) = NULL_TREE;
1372 duplicate_decls (spec, fn, is_friend);
1373 /* The call to duplicate_decls will have applied
1376 An explicit specialization of a function template
1377 is inline only if it is explicitly declared to be,
1378 and independently of whether its function template
1381 to the primary function; now copy the inline bits to
1382 the various clones. */
1383 FOR_EACH_CLONE (clone, fn)
1385 DECL_DECLARED_INLINE_P (clone)
1386 = DECL_DECLARED_INLINE_P (fn);
1387 DECL_SOURCE_LOCATION (clone)
1388 = DECL_SOURCE_LOCATION (fn);
1390 check_specialization_namespace (fn);
1395 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1397 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1398 /* Dup decl failed, but this is a new definition. Set the
1399 line number so any errors match this new
1401 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1407 return duplicate_decls (spec, fn, is_friend);
1409 /* A specialization must be declared in the same namespace as the
1410 template it is specializing. */
1411 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1412 && !check_specialization_namespace (tmpl))
1413 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1415 if (!optimize_specialization_lookup_p (tmpl))
1417 gcc_assert (tmpl && args && spec);
1418 *slot = ggc_alloc_spec_entry ();
1420 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1421 && PRIMARY_TEMPLATE_P (tmpl)
1422 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1423 /* TMPL is a forward declaration of a template function; keep a list
1424 of all specializations in case we need to reassign them to a friend
1425 template later in tsubst_friend_function. */
1426 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1427 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1433 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1434 TMPL and ARGS members, ignores SPEC. */
1437 eq_specializations (const void *p1, const void *p2)
1439 const spec_entry *e1 = (const spec_entry *)p1;
1440 const spec_entry *e2 = (const spec_entry *)p2;
1442 return (e1->tmpl == e2->tmpl
1443 && comp_template_args (e1->args, e2->args));
1446 /* Returns a hash for a template TMPL and template arguments ARGS. */
1449 hash_tmpl_and_args (tree tmpl, tree args)
1451 hashval_t val = DECL_UID (tmpl);
1452 return iterative_hash_template_arg (args, val);
1455 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1459 hash_specialization (const void *p)
1461 const spec_entry *e = (const spec_entry *)p;
1462 return hash_tmpl_and_args (e->tmpl, e->args);
1465 /* Recursively calculate a hash value for a template argument ARG, for use
1466 in the hash tables of template specializations. */
1469 iterative_hash_template_arg (tree arg, hashval_t val)
1471 unsigned HOST_WIDE_INT i;
1472 enum tree_code code;
1475 if (arg == NULL_TREE)
1476 return iterative_hash_object (arg, val);
1481 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1482 /* We can get one of these when re-hashing a previous entry in the middle
1483 of substituting into a pack expansion. Just look through it. */
1484 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1486 code = TREE_CODE (arg);
1487 tclass = TREE_CODE_CLASS (code);
1489 val = iterative_hash_object (code, val);
1496 case IDENTIFIER_NODE:
1497 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1501 int i, len = TREE_VEC_LENGTH (arg);
1502 for (i = 0; i < len; ++i)
1503 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1507 case TYPE_PACK_EXPANSION:
1508 case EXPR_PACK_EXPANSION:
1509 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1511 case TYPE_ARGUMENT_PACK:
1512 case NONTYPE_ARGUMENT_PACK:
1513 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1516 for (; arg; arg = TREE_CHAIN (arg))
1517 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1521 for (; arg; arg = OVL_NEXT (arg))
1522 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1528 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1530 val = iterative_hash_template_arg (field, val);
1531 val = iterative_hash_template_arg (value, val);
1537 if (!DECL_ARTIFICIAL (arg))
1539 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1540 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1542 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1545 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1548 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1549 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1551 case TEMPLATE_PARM_INDEX:
1552 val = iterative_hash_template_arg
1553 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1554 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1555 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1558 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1559 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1560 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1563 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1565 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1569 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1570 code = TREE_CODE (TREE_OPERAND (arg, 1));
1571 val = iterative_hash_object (code, val);
1572 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1575 /* A lambda can't appear in a template arg, but don't crash on
1577 gcc_assert (seen_error ());
1581 case STATIC_CAST_EXPR:
1582 case REINTERPRET_CAST_EXPR:
1583 case CONST_CAST_EXPR:
1584 case DYNAMIC_CAST_EXPR:
1586 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1587 /* Now hash operands as usual. */
1597 if (TYPE_CANONICAL (arg))
1598 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1600 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1601 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1602 /* Otherwise just compare the types during lookup. */
1605 case tcc_declaration:
1607 return iterative_hash_expr (arg, val);
1610 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1612 unsigned n = TREE_OPERAND_LENGTH (arg);
1613 for (i = 0; i < n; ++i)
1614 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1622 /* Unregister the specialization SPEC as a specialization of TMPL.
1623 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1624 if the SPEC was listed as a specialization of TMPL.
1626 Note that SPEC has been ggc_freed, so we can't look inside it. */
1629 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1634 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1635 elt.args = TI_ARGS (tinfo);
1636 elt.spec = NULL_TREE;
1638 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1641 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1642 gcc_assert (new_spec != NULL_TREE);
1643 (*slot)->spec = new_spec;
1650 /* Compare an entry in the local specializations hash table P1 (which
1651 is really a pointer to a TREE_LIST) with P2 (which is really a
1655 eq_local_specializations (const void *p1, const void *p2)
1657 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1660 /* Hash P1, an entry in the local specializations table. */
1663 hash_local_specialization (const void* p1)
1665 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1668 /* Like register_specialization, but for local declarations. We are
1669 registering SPEC, an instantiation of TMPL. */
1672 register_local_specialization (tree spec, tree tmpl)
1676 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1677 htab_hash_pointer (tmpl), INSERT);
1678 *slot = build_tree_list (spec, tmpl);
1681 /* TYPE is a class type. Returns true if TYPE is an explicitly
1682 specialized class. */
1685 explicit_class_specialization_p (tree type)
1687 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1689 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1692 /* Print the list of functions at FNS, going through all the overloads
1693 for each element of the list. Alternatively, FNS can not be a
1694 TREE_LIST, in which case it will be printed together with all the
1697 MORE and *STR should respectively be FALSE and NULL when the function
1698 is called from the outside. They are used internally on recursive
1699 calls. print_candidates manages the two parameters and leaves NULL
1700 in *STR when it ends. */
1703 print_candidates_1 (tree fns, bool more, const char **str)
1706 char *spaces = NULL;
1708 for (fn = fns; fn; fn = OVL_NEXT (fn))
1709 if (TREE_CODE (fn) == TREE_LIST)
1711 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1712 print_candidates_1 (TREE_VALUE (fn2),
1713 TREE_CHAIN (fn2) || more, str);
1719 /* Pick the prefix string. */
1720 if (!more && !OVL_NEXT (fns))
1722 error ("candidate is: %+#D", OVL_CURRENT (fn));
1726 *str = _("candidates are:");
1727 spaces = get_spaces (*str);
1729 error ("%s %+#D", *str, OVL_CURRENT (fn));
1730 *str = spaces ? spaces : *str;
1740 /* Print the list of candidate FNS in an error message. FNS can also
1741 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1744 print_candidates (tree fns)
1746 const char *str = NULL;
1747 print_candidates_1 (fns, false, &str);
1748 gcc_assert (str == NULL);
1751 /* Returns the template (one of the functions given by TEMPLATE_ID)
1752 which can be specialized to match the indicated DECL with the
1753 explicit template args given in TEMPLATE_ID. The DECL may be
1754 NULL_TREE if none is available. In that case, the functions in
1755 TEMPLATE_ID are non-members.
1757 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1758 specialization of a member template.
1760 The TEMPLATE_COUNT is the number of references to qualifying
1761 template classes that appeared in the name of the function. See
1762 check_explicit_specialization for a more accurate description.
1764 TSK indicates what kind of template declaration (if any) is being
1765 declared. TSK_TEMPLATE indicates that the declaration given by
1766 DECL, though a FUNCTION_DECL, has template parameters, and is
1767 therefore a template function.
1769 The template args (those explicitly specified and those deduced)
1770 are output in a newly created vector *TARGS_OUT.
1772 If it is impossible to determine the result, an error message is
1773 issued. The error_mark_node is returned to indicate failure. */
1776 determine_specialization (tree template_id,
1779 int need_member_template,
1785 tree explicit_targs;
1786 tree candidates = NULL_TREE;
1787 /* A TREE_LIST of templates of which DECL may be a specialization.
1788 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1789 corresponding TREE_PURPOSE is the set of template arguments that,
1790 when used to instantiate the template, would produce a function
1791 with the signature of DECL. */
1792 tree templates = NULL_TREE;
1794 struct cp_binding_level *b;
1796 *targs_out = NULL_TREE;
1798 if (template_id == error_mark_node || decl == error_mark_node)
1799 return error_mark_node;
1801 fns = TREE_OPERAND (template_id, 0);
1802 explicit_targs = TREE_OPERAND (template_id, 1);
1804 if (fns == error_mark_node)
1805 return error_mark_node;
1807 /* Check for baselinks. */
1808 if (BASELINK_P (fns))
1809 fns = BASELINK_FUNCTIONS (fns);
1811 if (!is_overloaded_fn (fns))
1813 error ("%qD is not a function template", fns);
1814 return error_mark_node;
1817 /* Count the number of template headers specified for this
1820 for (b = current_binding_level;
1821 b->kind == sk_template_parms;
1825 for (; fns; fns = OVL_NEXT (fns))
1827 tree fn = OVL_CURRENT (fns);
1829 if (TREE_CODE (fn) == TEMPLATE_DECL)
1831 tree decl_arg_types;
1834 /* In case of explicit specialization, we need to check if
1835 the number of template headers appearing in the specialization
1836 is correct. This is usually done in check_explicit_specialization,
1837 but the check done there cannot be exhaustive when specializing
1838 member functions. Consider the following code:
1840 template <> void A<int>::f(int);
1841 template <> template <> void A<int>::f(int);
1843 Assuming that A<int> is not itself an explicit specialization
1844 already, the first line specializes "f" which is a non-template
1845 member function, whilst the second line specializes "f" which
1846 is a template member function. So both lines are syntactically
1847 correct, and check_explicit_specialization does not reject
1850 Here, we can do better, as we are matching the specialization
1851 against the declarations. We count the number of template
1852 headers, and we check if they match TEMPLATE_COUNT + 1
1853 (TEMPLATE_COUNT is the number of qualifying template classes,
1854 plus there must be another header for the member template
1857 Notice that if header_count is zero, this is not a
1858 specialization but rather a template instantiation, so there
1859 is no check we can perform here. */
1860 if (header_count && header_count != template_count + 1)
1863 /* Check that the number of template arguments at the
1864 innermost level for DECL is the same as for FN. */
1865 if (current_binding_level->kind == sk_template_parms
1866 && !current_binding_level->explicit_spec_p
1867 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1868 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1869 (current_template_parms))))
1872 /* DECL might be a specialization of FN. */
1873 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1874 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1876 /* For a non-static member function, we need to make sure
1877 that the const qualification is the same. Since
1878 get_bindings does not try to merge the "this" parameter,
1879 we must do the comparison explicitly. */
1880 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1881 && !same_type_p (TREE_VALUE (fn_arg_types),
1882 TREE_VALUE (decl_arg_types)))
1885 /* Skip the "this" parameter and, for constructors of
1886 classes with virtual bases, the VTT parameter. A
1887 full specialization of a constructor will have a VTT
1888 parameter, but a template never will. */
1890 = skip_artificial_parms_for (decl, decl_arg_types);
1892 = skip_artificial_parms_for (fn, fn_arg_types);
1894 /* Check that the number of function parameters matches.
1896 template <class T> void f(int i = 0);
1897 template <> void f<int>();
1898 The specialization f<int> is invalid but is not caught
1899 by get_bindings below. */
1900 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1903 /* Function templates cannot be specializations; there are
1904 no partial specializations of functions. Therefore, if
1905 the type of DECL does not match FN, there is no
1907 if (tsk == tsk_template)
1909 if (compparms (fn_arg_types, decl_arg_types))
1910 candidates = tree_cons (NULL_TREE, fn, candidates);
1914 /* See whether this function might be a specialization of this
1916 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1919 /* We cannot deduce template arguments that when used to
1920 specialize TMPL will produce DECL. */
1923 /* Save this template, and the arguments deduced. */
1924 templates = tree_cons (targs, fn, templates);
1926 else if (need_member_template)
1927 /* FN is an ordinary member function, and we need a
1928 specialization of a member template. */
1930 else if (TREE_CODE (fn) != FUNCTION_DECL)
1931 /* We can get IDENTIFIER_NODEs here in certain erroneous
1934 else if (!DECL_FUNCTION_MEMBER_P (fn))
1935 /* This is just an ordinary non-member function. Nothing can
1936 be a specialization of that. */
1938 else if (DECL_ARTIFICIAL (fn))
1939 /* Cannot specialize functions that are created implicitly. */
1943 tree decl_arg_types;
1945 /* This is an ordinary member function. However, since
1946 we're here, we can assume it's enclosing class is a
1947 template class. For example,
1949 template <typename T> struct S { void f(); };
1950 template <> void S<int>::f() {}
1952 Here, S<int>::f is a non-template, but S<int> is a
1953 template class. If FN has the same type as DECL, we
1954 might be in business. */
1956 if (!DECL_TEMPLATE_INFO (fn))
1957 /* Its enclosing class is an explicit specialization
1958 of a template class. This is not a candidate. */
1961 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1962 TREE_TYPE (TREE_TYPE (fn))))
1963 /* The return types differ. */
1966 /* Adjust the type of DECL in case FN is a static member. */
1967 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1968 if (DECL_STATIC_FUNCTION_P (fn)
1969 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1970 decl_arg_types = TREE_CHAIN (decl_arg_types);
1972 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1975 candidates = tree_cons (NULL_TREE, fn, candidates);
1979 if (templates && TREE_CHAIN (templates))
1985 It is possible for a specialization with a given function
1986 signature to be instantiated from more than one function
1987 template. In such cases, explicit specification of the
1988 template arguments must be used to uniquely identify the
1989 function template specialization being specialized.
1991 Note that here, there's no suggestion that we're supposed to
1992 determine which of the candidate templates is most
1993 specialized. However, we, also have:
1997 Partial ordering of overloaded function template
1998 declarations is used in the following contexts to select
1999 the function template to which a function template
2000 specialization refers:
2002 -- when an explicit specialization refers to a function
2005 So, we do use the partial ordering rules, at least for now.
2006 This extension can only serve to make invalid programs valid,
2007 so it's safe. And, there is strong anecdotal evidence that
2008 the committee intended the partial ordering rules to apply;
2009 the EDG front end has that behavior, and John Spicer claims
2010 that the committee simply forgot to delete the wording in
2011 [temp.expl.spec]. */
2012 tree tmpl = most_specialized_instantiation (templates);
2013 if (tmpl != error_mark_node)
2016 TREE_CHAIN (templates) = NULL_TREE;
2020 if (templates == NULL_TREE && candidates == NULL_TREE)
2022 error ("template-id %qD for %q+D does not match any template "
2023 "declaration", template_id, decl);
2024 if (header_count && header_count != template_count + 1)
2025 inform (input_location, "saw %d %<template<>%>, need %d for "
2026 "specializing a member function template",
2027 header_count, template_count + 1);
2028 return error_mark_node;
2030 else if ((templates && TREE_CHAIN (templates))
2031 || (candidates && TREE_CHAIN (candidates))
2032 || (templates && candidates))
2034 error ("ambiguous template specialization %qD for %q+D",
2036 candidates = chainon (candidates, templates);
2037 print_candidates (candidates);
2038 return error_mark_node;
2041 /* We have one, and exactly one, match. */
2044 tree fn = TREE_VALUE (candidates);
2045 *targs_out = copy_node (DECL_TI_ARGS (fn));
2046 /* DECL is a re-declaration or partial instantiation of a template
2048 if (TREE_CODE (fn) == TEMPLATE_DECL)
2050 /* It was a specialization of an ordinary member function in a
2052 return DECL_TI_TEMPLATE (fn);
2055 /* It was a specialization of a template. */
2056 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2057 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2059 *targs_out = copy_node (targs);
2060 SET_TMPL_ARGS_LEVEL (*targs_out,
2061 TMPL_ARGS_DEPTH (*targs_out),
2062 TREE_PURPOSE (templates));
2065 *targs_out = TREE_PURPOSE (templates);
2066 return TREE_VALUE (templates);
2069 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2070 but with the default argument values filled in from those in the
2074 copy_default_args_to_explicit_spec_1 (tree spec_types,
2077 tree new_spec_types;
2082 if (spec_types == void_list_node)
2083 return void_list_node;
2085 /* Substitute into the rest of the list. */
2087 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2088 TREE_CHAIN (tmpl_types));
2090 /* Add the default argument for this parameter. */
2091 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2092 TREE_VALUE (spec_types),
2096 /* DECL is an explicit specialization. Replicate default arguments
2097 from the template it specializes. (That way, code like:
2099 template <class T> void f(T = 3);
2100 template <> void f(double);
2103 works, as required.) An alternative approach would be to look up
2104 the correct default arguments at the call-site, but this approach
2105 is consistent with how implicit instantiations are handled. */
2108 copy_default_args_to_explicit_spec (tree decl)
2113 tree new_spec_types;
2117 tree object_type = NULL_TREE;
2118 tree in_charge = NULL_TREE;
2119 tree vtt = NULL_TREE;
2121 /* See if there's anything we need to do. */
2122 tmpl = DECL_TI_TEMPLATE (decl);
2123 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2124 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2125 if (TREE_PURPOSE (t))
2130 old_type = TREE_TYPE (decl);
2131 spec_types = TYPE_ARG_TYPES (old_type);
2133 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2135 /* Remove the this pointer, but remember the object's type for
2137 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2138 spec_types = TREE_CHAIN (spec_types);
2139 tmpl_types = TREE_CHAIN (tmpl_types);
2141 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2143 /* DECL may contain more parameters than TMPL due to the extra
2144 in-charge parameter in constructors and destructors. */
2145 in_charge = spec_types;
2146 spec_types = TREE_CHAIN (spec_types);
2148 if (DECL_HAS_VTT_PARM_P (decl))
2151 spec_types = TREE_CHAIN (spec_types);
2155 /* Compute the merged default arguments. */
2157 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2159 /* Compute the new FUNCTION_TYPE. */
2163 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2168 /* Put the in-charge parameter back. */
2169 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2170 TREE_VALUE (in_charge),
2173 new_type = build_method_type_directly (object_type,
2174 TREE_TYPE (old_type),
2178 new_type = build_function_type (TREE_TYPE (old_type),
2180 new_type = cp_build_type_attribute_variant (new_type,
2181 TYPE_ATTRIBUTES (old_type));
2182 new_type = build_exception_variant (new_type,
2183 TYPE_RAISES_EXCEPTIONS (old_type));
2184 TREE_TYPE (decl) = new_type;
2187 /* Check to see if the function just declared, as indicated in
2188 DECLARATOR, and in DECL, is a specialization of a function
2189 template. We may also discover that the declaration is an explicit
2190 instantiation at this point.
2192 Returns DECL, or an equivalent declaration that should be used
2193 instead if all goes well. Issues an error message if something is
2194 amiss. Returns error_mark_node if the error is not easily
2197 FLAGS is a bitmask consisting of the following flags:
2199 2: The function has a definition.
2200 4: The function is a friend.
2202 The TEMPLATE_COUNT is the number of references to qualifying
2203 template classes that appeared in the name of the function. For
2206 template <class T> struct S { void f(); };
2209 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2210 classes are not counted in the TEMPLATE_COUNT, so that in
2212 template <class T> struct S {};
2213 template <> struct S<int> { void f(); }
2214 template <> void S<int>::f();
2216 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2217 invalid; there should be no template <>.)
2219 If the function is a specialization, it is marked as such via
2220 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2221 is set up correctly, and it is added to the list of specializations
2222 for that template. */
2225 check_explicit_specialization (tree declarator,
2230 int have_def = flags & 2;
2231 int is_friend = flags & 4;
2232 int specialization = 0;
2233 int explicit_instantiation = 0;
2234 int member_specialization = 0;
2235 tree ctype = DECL_CLASS_CONTEXT (decl);
2236 tree dname = DECL_NAME (decl);
2241 if (!processing_specialization)
2244 tsk = tsk_excessive_parms;
2247 tsk = current_tmpl_spec_kind (template_count);
2252 if (processing_specialization)
2255 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2257 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2260 /* This could be something like:
2262 template <class T> void f(T);
2263 class S { friend void f<>(int); } */
2267 /* This case handles bogus declarations like template <>
2268 template <class T> void f<int>(); */
2270 error ("template-id %qD in declaration of primary template",
2277 case tsk_invalid_member_spec:
2278 /* The error has already been reported in
2279 check_specialization_scope. */
2280 return error_mark_node;
2282 case tsk_invalid_expl_inst:
2283 error ("template parameter list used in explicit instantiation");
2289 error ("definition provided for explicit instantiation");
2291 explicit_instantiation = 1;
2294 case tsk_excessive_parms:
2295 case tsk_insufficient_parms:
2296 if (tsk == tsk_excessive_parms)
2297 error ("too many template parameter lists in declaration of %qD",
2299 else if (template_header_count)
2300 error("too few template parameter lists in declaration of %qD", decl);
2302 error("explicit specialization of %qD must be introduced by "
2303 "%<template <>%>", decl);
2307 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2309 member_specialization = 1;
2315 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2317 /* This case handles bogus declarations like template <>
2318 template <class T> void f<int>(); */
2320 if (uses_template_parms (declarator))
2321 error ("function template partial specialization %qD "
2322 "is not allowed", declarator);
2324 error ("template-id %qD in declaration of primary template",
2329 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2330 /* This is a specialization of a member template, without
2331 specialization the containing class. Something like:
2333 template <class T> struct S {
2334 template <class U> void f (U);
2336 template <> template <class U> void S<int>::f(U) {}
2338 That's a specialization -- but of the entire template. */
2346 if (specialization || member_specialization)
2348 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2349 for (; t; t = TREE_CHAIN (t))
2350 if (TREE_PURPOSE (t))
2352 permerror (input_location,
2353 "default argument specified in explicit specialization");
2358 if (specialization || member_specialization || explicit_instantiation)
2360 tree tmpl = NULL_TREE;
2361 tree targs = NULL_TREE;
2363 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2364 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2368 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2373 /* If there is no class context, the explicit instantiation
2374 must be at namespace scope. */
2375 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2377 /* Find the namespace binding, using the declaration
2379 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2381 if (fns == error_mark_node || !is_overloaded_fn (fns))
2383 error ("%qD is not a template function", dname);
2384 fns = error_mark_node;
2388 tree fn = OVL_CURRENT (fns);
2389 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2390 CP_DECL_CONTEXT (fn)))
2391 error ("%qD is not declared in %qD",
2392 decl, current_namespace);
2396 declarator = lookup_template_function (fns, NULL_TREE);
2399 if (declarator == error_mark_node)
2400 return error_mark_node;
2402 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2404 if (!explicit_instantiation)
2405 /* A specialization in class scope. This is invalid,
2406 but the error will already have been flagged by
2407 check_specialization_scope. */
2408 return error_mark_node;
2411 /* It's not valid to write an explicit instantiation in
2414 class C { template void f(); }
2416 This case is caught by the parser. However, on
2419 template class C { void f(); };
2421 (which is invalid) we can get here. The error will be
2428 else if (ctype != NULL_TREE
2429 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2432 /* Find the list of functions in ctype that have the same
2433 name as the declared function. */
2434 tree name = TREE_OPERAND (declarator, 0);
2435 tree fns = NULL_TREE;
2438 if (constructor_name_p (name, ctype))
2440 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2442 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2443 : !CLASSTYPE_DESTRUCTORS (ctype))
2445 /* From [temp.expl.spec]:
2447 If such an explicit specialization for the member
2448 of a class template names an implicitly-declared
2449 special member function (clause _special_), the
2450 program is ill-formed.
2452 Similar language is found in [temp.explicit]. */
2453 error ("specialization of implicitly-declared special member function");
2454 return error_mark_node;
2457 name = is_constructor ? ctor_identifier : dtor_identifier;
2460 if (!DECL_CONV_FN_P (decl))
2462 idx = lookup_fnfields_1 (ctype, name);
2464 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2468 VEC(tree,gc) *methods;
2471 /* For a type-conversion operator, we cannot do a
2472 name-based lookup. We might be looking for `operator
2473 int' which will be a specialization of `operator T'.
2474 So, we find *all* the conversion operators, and then
2475 select from them. */
2478 methods = CLASSTYPE_METHOD_VEC (ctype);
2480 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2481 VEC_iterate (tree, methods, idx, ovl);
2484 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2485 /* There are no more conversion functions. */
2488 /* Glue all these conversion functions together
2489 with those we already have. */
2490 for (; ovl; ovl = OVL_NEXT (ovl))
2491 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2495 if (fns == NULL_TREE)
2497 error ("no member function %qD declared in %qT", name, ctype);
2498 return error_mark_node;
2501 TREE_OPERAND (declarator, 0) = fns;
2504 /* Figure out what exactly is being specialized at this point.
2505 Note that for an explicit instantiation, even one for a
2506 member function, we cannot tell apriori whether the
2507 instantiation is for a member template, or just a member
2508 function of a template class. Even if a member template is
2509 being instantiated, the member template arguments may be
2510 elided if they can be deduced from the rest of the
2512 tmpl = determine_specialization (declarator, decl,
2514 member_specialization,
2518 if (!tmpl || tmpl == error_mark_node)
2519 /* We couldn't figure out what this declaration was
2521 return error_mark_node;
2524 tree gen_tmpl = most_general_template (tmpl);
2526 if (explicit_instantiation)
2528 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2529 is done by do_decl_instantiation later. */
2531 int arg_depth = TMPL_ARGS_DEPTH (targs);
2532 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2534 if (arg_depth > parm_depth)
2536 /* If TMPL is not the most general template (for
2537 example, if TMPL is a friend template that is
2538 injected into namespace scope), then there will
2539 be too many levels of TARGS. Remove some of them
2544 new_targs = make_tree_vec (parm_depth);
2545 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2546 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2547 = TREE_VEC_ELT (targs, i);
2551 return instantiate_template (tmpl, targs, tf_error);
2554 /* If we thought that the DECL was a member function, but it
2555 turns out to be specializing a static member function,
2556 make DECL a static member function as well. */
2557 if (DECL_STATIC_FUNCTION_P (tmpl)
2558 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2559 revert_static_member_fn (decl);
2561 /* If this is a specialization of a member template of a
2562 template class, we want to return the TEMPLATE_DECL, not
2563 the specialization of it. */
2564 if (tsk == tsk_template)
2566 tree result = DECL_TEMPLATE_RESULT (tmpl);
2567 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2568 DECL_INITIAL (result) = NULL_TREE;
2572 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2573 DECL_SOURCE_LOCATION (result)
2574 = DECL_SOURCE_LOCATION (decl);
2575 /* We want to use the argument list specified in the
2576 definition, not in the original declaration. */
2577 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2578 for (parm = DECL_ARGUMENTS (result); parm;
2579 parm = DECL_CHAIN (parm))
2580 DECL_CONTEXT (parm) = result;
2582 return register_specialization (tmpl, gen_tmpl, targs,
2586 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2587 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2589 /* Inherit default function arguments from the template
2590 DECL is specializing. */
2591 copy_default_args_to_explicit_spec (decl);
2593 /* This specialization has the same protection as the
2594 template it specializes. */
2595 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2596 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2598 /* 7.1.1-1 [dcl.stc]
2600 A storage-class-specifier shall not be specified in an
2601 explicit specialization...
2603 The parser rejects these, so unless action is taken here,
2604 explicit function specializations will always appear with
2607 The action recommended by the C++ CWG in response to C++
2608 defect report 605 is to make the storage class and linkage
2609 of the explicit specialization match the templated function:
2611 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2613 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2615 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2616 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2618 /* This specialization has the same linkage and visibility as
2619 the function template it specializes. */
2620 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2621 if (! TREE_PUBLIC (decl))
2623 DECL_INTERFACE_KNOWN (decl) = 1;
2624 DECL_NOT_REALLY_EXTERN (decl) = 1;
2626 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2627 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2629 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2630 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2634 /* If DECL is a friend declaration, declared using an
2635 unqualified name, the namespace associated with DECL may
2636 have been set incorrectly. For example, in:
2638 template <typename T> void f(T);
2640 struct S { friend void f<int>(int); }
2643 we will have set the DECL_CONTEXT for the friend
2644 declaration to N, rather than to the global namespace. */
2645 if (DECL_NAMESPACE_SCOPE_P (decl))
2646 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2648 if (is_friend && !have_def)
2649 /* This is not really a declaration of a specialization.
2650 It's just the name of an instantiation. But, it's not
2651 a request for an instantiation, either. */
2652 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2653 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2654 /* This is indeed a specialization. In case of constructors
2655 and destructors, we need in-charge and not-in-charge
2656 versions in V3 ABI. */
2657 clone_function_decl (decl, /*update_method_vec_p=*/0);
2659 /* Register this specialization so that we can find it
2661 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2668 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2669 parameters. These are represented in the same format used for
2670 DECL_TEMPLATE_PARMS. */
2673 comp_template_parms (const_tree parms1, const_tree parms2)
2678 if (parms1 == parms2)
2681 for (p1 = parms1, p2 = parms2;
2682 p1 != NULL_TREE && p2 != NULL_TREE;
2683 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2685 tree t1 = TREE_VALUE (p1);
2686 tree t2 = TREE_VALUE (p2);
2689 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2690 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2692 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2695 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2697 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2698 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2700 /* If either of the template parameters are invalid, assume
2701 they match for the sake of error recovery. */
2702 if (parm1 == error_mark_node || parm2 == error_mark_node)
2705 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2708 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2709 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2710 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2712 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2717 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2718 /* One set of parameters has more parameters lists than the
2725 /* Determine whether PARM is a parameter pack. */
2728 template_parameter_pack_p (const_tree parm)
2730 /* Determine if we have a non-type template parameter pack. */
2731 if (TREE_CODE (parm) == PARM_DECL)
2732 return (DECL_TEMPLATE_PARM_P (parm)
2733 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2735 /* If this is a list of template parameters, we could get a
2736 TYPE_DECL or a TEMPLATE_DECL. */
2737 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2738 parm = TREE_TYPE (parm);
2740 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2741 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2742 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2745 /* Determine if T is a function parameter pack. */
2748 function_parameter_pack_p (const_tree t)
2750 if (t && TREE_CODE (t) == PARM_DECL)
2751 return FUNCTION_PARAMETER_PACK_P (t);
2755 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2756 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2759 get_function_template_decl (const_tree primary_func_tmpl_inst)
2761 if (! primary_func_tmpl_inst
2762 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2763 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2766 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2769 /* Return true iff the function parameter PARAM_DECL was expanded
2770 from the function parameter pack PACK. */
2773 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2775 if (DECL_ARTIFICIAL (param_decl)
2776 || !function_parameter_pack_p (pack))
2779 /* The parameter pack and its pack arguments have the same
2781 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2784 /* Determine whether ARGS describes a variadic template args list,
2785 i.e., one that is terminated by a template argument pack. */
2788 template_args_variadic_p (tree args)
2793 if (args == NULL_TREE)
2796 args = INNERMOST_TEMPLATE_ARGS (args);
2797 nargs = TREE_VEC_LENGTH (args);
2802 last_parm = TREE_VEC_ELT (args, nargs - 1);
2804 return ARGUMENT_PACK_P (last_parm);
2807 /* Generate a new name for the parameter pack name NAME (an
2808 IDENTIFIER_NODE) that incorporates its */
2811 make_ith_pack_parameter_name (tree name, int i)
2813 /* Munge the name to include the parameter index. */
2814 #define NUMBUF_LEN 128
2815 char numbuf[NUMBUF_LEN];
2819 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2820 newname_len = IDENTIFIER_LENGTH (name)
2821 + strlen (numbuf) + 2;
2822 newname = (char*)alloca (newname_len);
2823 snprintf (newname, newname_len,
2824 "%s#%i", IDENTIFIER_POINTER (name), i);
2825 return get_identifier (newname);
2828 /* Return true if T is a primary function
2829 or class template instantiation. */
2832 primary_template_instantiation_p (const_tree t)
2837 if (TREE_CODE (t) == FUNCTION_DECL)
2838 return DECL_LANG_SPECIFIC (t)
2839 && DECL_TEMPLATE_INSTANTIATION (t)
2840 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2841 else if (CLASS_TYPE_P (t))
2842 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2843 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2847 /* Return true if PARM is a template template parameter. */
2850 template_template_parameter_p (const_tree parm)
2852 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2855 /* Return the template parameters of T if T is a
2856 primary template instantiation, NULL otherwise. */
2859 get_primary_template_innermost_parameters (const_tree t)
2861 tree parms = NULL, template_info = NULL;
2863 if ((template_info = get_template_info (t))
2864 && primary_template_instantiation_p (t))
2865 parms = INNERMOST_TEMPLATE_PARMS
2866 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2871 /* Return the template parameters of the LEVELth level from the full list
2872 of template parameters PARMS. */
2875 get_template_parms_at_level (tree parms, int level)
2879 || TREE_CODE (parms) != TREE_LIST
2880 || level > TMPL_PARMS_DEPTH (parms))
2883 for (p = parms; p; p = TREE_CHAIN (p))
2884 if (TMPL_PARMS_DEPTH (p) == level)
2890 /* Returns the template arguments of T if T is a template instantiation,
2894 get_template_innermost_arguments (const_tree t)
2896 tree args = NULL, template_info = NULL;
2898 if ((template_info = get_template_info (t))
2899 && TI_ARGS (template_info))
2900 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2905 /* Return the argument pack elements of T if T is a template argument pack,
2909 get_template_argument_pack_elems (const_tree t)
2911 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2912 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2915 return ARGUMENT_PACK_ARGS (t);
2918 /* Structure used to track the progress of find_parameter_packs_r. */
2919 struct find_parameter_pack_data
2921 /* TREE_LIST that will contain all of the parameter packs found by
2923 tree* parameter_packs;
2925 /* Set of AST nodes that have been visited by the traversal. */
2926 struct pointer_set_t *visited;
2929 /* Identifies all of the argument packs that occur in a template
2930 argument and appends them to the TREE_LIST inside DATA, which is a
2931 find_parameter_pack_data structure. This is a subroutine of
2932 make_pack_expansion and uses_parameter_packs. */
2934 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2937 struct find_parameter_pack_data* ppd =
2938 (struct find_parameter_pack_data*)data;
2939 bool parameter_pack_p = false;
2941 /* Identify whether this is a parameter pack or not. */
2942 switch (TREE_CODE (t))
2944 case TEMPLATE_PARM_INDEX:
2945 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2946 parameter_pack_p = true;
2949 case TEMPLATE_TYPE_PARM:
2950 case TEMPLATE_TEMPLATE_PARM:
2951 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2952 parameter_pack_p = true;
2956 if (FUNCTION_PARAMETER_PACK_P (t))
2958 /* We don't want to walk into the type of a PARM_DECL,
2959 because we don't want to see the type parameter pack. */
2961 parameter_pack_p = true;
2966 /* Not a parameter pack. */
2970 if (parameter_pack_p)
2972 /* Add this parameter pack to the list. */
2973 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2977 cp_walk_tree (&TYPE_CONTEXT (t),
2978 &find_parameter_packs_r, ppd, ppd->visited);
2980 /* This switch statement will return immediately if we don't find a
2982 switch (TREE_CODE (t))
2984 case TEMPLATE_PARM_INDEX:
2987 case BOUND_TEMPLATE_TEMPLATE_PARM:
2988 /* Check the template itself. */
2989 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2990 &find_parameter_packs_r, ppd, ppd->visited);
2991 /* Check the template arguments. */
2992 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2997 case TEMPLATE_TYPE_PARM:
2998 case TEMPLATE_TEMPLATE_PARM:
3005 if (TYPE_PTRMEMFUNC_P (t))
3011 if (TYPE_TEMPLATE_INFO (t))
3012 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3013 &find_parameter_packs_r, ppd, ppd->visited);
3019 cp_walk_tree (&TREE_TYPE (t),
3020 &find_parameter_packs_r, ppd, ppd->visited);
3024 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3029 case TYPE_PACK_EXPANSION:
3030 case EXPR_PACK_EXPANSION:
3035 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3040 case IDENTIFIER_NODE:
3041 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3053 /* Determines if the expression or type T uses any parameter packs. */
3055 uses_parameter_packs (tree t)
3057 tree parameter_packs = NULL_TREE;
3058 struct find_parameter_pack_data ppd;
3059 ppd.parameter_packs = ¶meter_packs;
3060 ppd.visited = pointer_set_create ();
3061 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3062 pointer_set_destroy (ppd.visited);
3063 return parameter_packs != NULL_TREE;
3066 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3067 representation a base-class initializer into a parameter pack
3068 expansion. If all goes well, the resulting node will be an
3069 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3072 make_pack_expansion (tree arg)
3075 tree parameter_packs = NULL_TREE;
3076 bool for_types = false;
3077 struct find_parameter_pack_data ppd;
3079 if (!arg || arg == error_mark_node)
3082 if (TREE_CODE (arg) == TREE_LIST)
3084 /* The only time we will see a TREE_LIST here is for a base
3085 class initializer. In this case, the TREE_PURPOSE will be a
3086 _TYPE node (representing the base class expansion we're
3087 initializing) and the TREE_VALUE will be a TREE_LIST
3088 containing the initialization arguments.
3090 The resulting expansion looks somewhat different from most
3091 expansions. Rather than returning just one _EXPANSION, we
3092 return a TREE_LIST whose TREE_PURPOSE is a
3093 TYPE_PACK_EXPANSION containing the bases that will be
3094 initialized. The TREE_VALUE will be identical to the
3095 original TREE_VALUE, which is a list of arguments that will
3096 be passed to each base. We do not introduce any new pack
3097 expansion nodes into the TREE_VALUE (although it is possible
3098 that some already exist), because the TREE_PURPOSE and
3099 TREE_VALUE all need to be expanded together with the same
3100 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3101 resulting TREE_PURPOSE will mention the parameter packs in
3102 both the bases and the arguments to the bases. */
3105 tree parameter_packs = NULL_TREE;
3107 /* Determine which parameter packs will be used by the base
3109 ppd.visited = pointer_set_create ();
3110 ppd.parameter_packs = ¶meter_packs;
3111 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3114 if (parameter_packs == NULL_TREE)
3116 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3117 pointer_set_destroy (ppd.visited);
3118 return error_mark_node;
3121 if (TREE_VALUE (arg) != void_type_node)
3123 /* Collect the sets of parameter packs used in each of the
3124 initialization arguments. */
3125 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3127 /* Determine which parameter packs will be expanded in this
3129 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3134 pointer_set_destroy (ppd.visited);
3136 /* Create the pack expansion type for the base type. */
3137 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3138 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3139 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3141 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3142 they will rarely be compared to anything. */
3143 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3145 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3148 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3151 /* Build the PACK_EXPANSION_* node. */
3153 ? cxx_make_type (TYPE_PACK_EXPANSION)
3154 : make_node (EXPR_PACK_EXPANSION);
3155 SET_PACK_EXPANSION_PATTERN (result, arg);
3156 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3158 /* Propagate type and const-expression information. */
3159 TREE_TYPE (result) = TREE_TYPE (arg);
3160 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3163 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3164 they will rarely be compared to anything. */
3165 SET_TYPE_STRUCTURAL_EQUALITY (result);
3167 /* Determine which parameter packs will be expanded. */
3168 ppd.parameter_packs = ¶meter_packs;
3169 ppd.visited = pointer_set_create ();
3170 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3171 pointer_set_destroy (ppd.visited);
3173 /* Make sure we found some parameter packs. */
3174 if (parameter_packs == NULL_TREE)
3177 error ("expansion pattern %<%T%> contains no argument packs", arg);
3179 error ("expansion pattern %<%E%> contains no argument packs", arg);
3180 return error_mark_node;
3182 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3187 /* Checks T for any "bare" parameter packs, which have not yet been
3188 expanded, and issues an error if any are found. This operation can
3189 only be done on full expressions or types (e.g., an expression
3190 statement, "if" condition, etc.), because we could have expressions like:
3192 foo(f(g(h(args)))...)
3194 where "args" is a parameter pack. check_for_bare_parameter_packs
3195 should not be called for the subexpressions args, h(args),
3196 g(h(args)), or f(g(h(args))), because we would produce erroneous
3199 Returns TRUE and emits an error if there were bare parameter packs,
3200 returns FALSE otherwise. */
3202 check_for_bare_parameter_packs (tree t)
3204 tree parameter_packs = NULL_TREE;
3205 struct find_parameter_pack_data ppd;
3207 if (!processing_template_decl || !t || t == error_mark_node)
3210 if (TREE_CODE (t) == TYPE_DECL)
3213 ppd.parameter_packs = ¶meter_packs;
3214 ppd.visited = pointer_set_create ();
3215 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3216 pointer_set_destroy (ppd.visited);
3218 if (parameter_packs)
3220 error ("parameter packs not expanded with %<...%>:");
3221 while (parameter_packs)
3223 tree pack = TREE_VALUE (parameter_packs);
3224 tree name = NULL_TREE;
3226 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3227 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3228 name = TYPE_NAME (pack);
3229 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3230 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3232 name = DECL_NAME (pack);
3235 inform (input_location, " %qD", name);
3237 inform (input_location, " <anonymous>");
3239 parameter_packs = TREE_CHAIN (parameter_packs);
3248 /* Expand any parameter packs that occur in the template arguments in
3251 expand_template_argument_pack (tree args)
3253 tree result_args = NULL_TREE;
3254 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3255 int num_result_args = -1;
3256 int non_default_args_count = -1;
3258 /* First, determine if we need to expand anything, and the number of
3259 slots we'll need. */
3260 for (in_arg = 0; in_arg < nargs; ++in_arg)
3262 tree arg = TREE_VEC_ELT (args, in_arg);
3263 if (arg == NULL_TREE)
3265 if (ARGUMENT_PACK_P (arg))
3267 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3268 if (num_result_args < 0)
3269 num_result_args = in_arg + num_packed;
3271 num_result_args += num_packed;
3275 if (num_result_args >= 0)
3280 /* If no expansion is necessary, we're done. */
3281 if (num_result_args < 0)
3284 /* Expand arguments. */
3285 result_args = make_tree_vec (num_result_args);
3286 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3287 non_default_args_count =
3288 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3289 for (in_arg = 0; in_arg < nargs; ++in_arg)
3291 tree arg = TREE_VEC_ELT (args, in_arg);
3292 if (ARGUMENT_PACK_P (arg))
3294 tree packed = ARGUMENT_PACK_ARGS (arg);
3295 int i, num_packed = TREE_VEC_LENGTH (packed);
3296 for (i = 0; i < num_packed; ++i, ++out_arg)
3297 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3298 if (non_default_args_count > 0)
3299 non_default_args_count += num_packed;
3303 TREE_VEC_ELT (result_args, out_arg) = arg;
3307 if (non_default_args_count >= 0)
3308 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3312 /* Checks if DECL shadows a template parameter.
3314 [temp.local]: A template-parameter shall not be redeclared within its
3315 scope (including nested scopes).
3317 Emits an error and returns TRUE if the DECL shadows a parameter,
3318 returns FALSE otherwise. */
3321 check_template_shadow (tree decl)
3325 /* If we're not in a template, we can't possibly shadow a template
3327 if (!current_template_parms)
3330 /* Figure out what we're shadowing. */
3331 if (TREE_CODE (decl) == OVERLOAD)
3332 decl = OVL_CURRENT (decl);
3333 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3335 /* If there's no previous binding for this name, we're not shadowing
3336 anything, let alone a template parameter. */
3340 /* If we're not shadowing a template parameter, we're done. Note
3341 that OLDDECL might be an OVERLOAD (or perhaps even an
3342 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3344 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3347 /* We check for decl != olddecl to avoid bogus errors for using a
3348 name inside a class. We check TPFI to avoid duplicate errors for
3349 inline member templates. */
3351 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3354 error ("declaration of %q+#D", decl);
3355 error (" shadows template parm %q+#D", olddecl);
3359 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3360 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3361 template parameters. */
3364 build_template_parm_index (int index,
3371 tree t = make_node (TEMPLATE_PARM_INDEX);
3372 TEMPLATE_PARM_IDX (t) = index;
3373 TEMPLATE_PARM_LEVEL (t) = level;
3374 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3375 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3376 TEMPLATE_PARM_DECL (t) = decl;
3377 TREE_TYPE (t) = type;
3378 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3379 TREE_READONLY (t) = TREE_READONLY (decl);
3384 /* Find the canonical type parameter for the given template type
3385 parameter. Returns the canonical type parameter, which may be TYPE
3386 if no such parameter existed. */
3389 canonical_type_parameter (tree type)
3392 int idx = TEMPLATE_TYPE_IDX (type);
3393 if (!canonical_template_parms)
3394 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3396 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3397 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3399 list = VEC_index (tree, canonical_template_parms, idx);
3400 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3401 list = TREE_CHAIN (list);
3404 return TREE_VALUE (list);
3407 VEC_replace(tree, canonical_template_parms, idx,
3408 tree_cons (NULL_TREE, type,
3409 VEC_index (tree, canonical_template_parms, idx)));
3414 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3415 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3416 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3417 new one is created. */
3420 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3421 tsubst_flags_t complain)
3423 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3424 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3425 != TEMPLATE_PARM_LEVEL (index) - levels)
3426 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3428 tree orig_decl = TEMPLATE_PARM_DECL (index);
3431 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3432 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3433 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3434 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3435 DECL_ARTIFICIAL (decl) = 1;
3436 SET_DECL_TEMPLATE_PARM_P (decl);
3438 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3439 TEMPLATE_PARM_LEVEL (index) - levels,
3440 TEMPLATE_PARM_ORIG_LEVEL (index),
3441 TEMPLATE_PARM_NUM_SIBLINGS (index),
3443 TEMPLATE_PARM_DESCENDANTS (index) = t;
3444 TEMPLATE_PARM_PARAMETER_PACK (t)
3445 = TEMPLATE_PARM_PARAMETER_PACK (index);
3447 /* Template template parameters need this. */
3448 if (TREE_CODE (decl) == TEMPLATE_DECL)
3449 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3450 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3454 return TEMPLATE_PARM_DESCENDANTS (index);
3457 /* Process information from new template parameter PARM and append it
3458 to the LIST being built. This new parameter is a non-type
3459 parameter iff IS_NON_TYPE is true. This new parameter is a
3460 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3461 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3462 parameter list PARM belongs to. This is used used to create a
3463 proper canonical type for the type of PARM that is to be created,
3464 iff PARM is a type. If the size is not known, this parameter shall
3468 process_template_parm (tree list, location_t parm_loc, tree parm,
3469 bool is_non_type, bool is_parameter_pack,
3470 unsigned num_template_parms)
3477 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3478 defval = TREE_PURPOSE (parm);
3482 tree p = tree_last (list);
3484 if (p && TREE_VALUE (p) != error_mark_node)
3487 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3488 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3490 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3500 parm = TREE_VALUE (parm);
3502 SET_DECL_TEMPLATE_PARM_P (parm);
3504 if (TREE_TYPE (parm) == error_mark_node)
3506 err_parm_list = build_tree_list (defval, parm);
3507 TREE_VALUE (err_parm_list) = error_mark_node;
3508 return chainon (list, err_parm_list);
3514 The top-level cv-qualifiers on the template-parameter are
3515 ignored when determining its type. */
3516 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3517 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3519 err_parm_list = build_tree_list (defval, parm);
3520 TREE_VALUE (err_parm_list) = error_mark_node;
3521 return chainon (list, err_parm_list);
3524 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3526 /* This template parameter is not a parameter pack, but it
3527 should be. Complain about "bare" parameter packs. */
3528 check_for_bare_parameter_packs (TREE_TYPE (parm));
3530 /* Recover by calling this a parameter pack. */
3531 is_parameter_pack = true;
3535 /* A template parameter is not modifiable. */
3536 TREE_CONSTANT (parm) = 1;
3537 TREE_READONLY (parm) = 1;
3538 decl = build_decl (parm_loc,
3539 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3540 TREE_CONSTANT (decl) = 1;
3541 TREE_READONLY (decl) = 1;
3542 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3543 = build_template_parm_index (idx, processing_template_decl,
3544 processing_template_decl,
3546 decl, TREE_TYPE (parm));
3548 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3549 = is_parameter_pack;
3554 parm = TREE_VALUE (TREE_VALUE (parm));
3556 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3558 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3559 /* This is for distinguishing between real templates and template
3560 template parameters */
3561 TREE_TYPE (parm) = t;
3562 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3567 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3568 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3569 decl = build_decl (parm_loc,
3570 TYPE_DECL, parm, t);
3573 TYPE_NAME (t) = decl;
3574 TYPE_STUB_DECL (t) = decl;
3576 TEMPLATE_TYPE_PARM_INDEX (t)
3577 = build_template_parm_index (idx, processing_template_decl,
3578 processing_template_decl,
3580 decl, TREE_TYPE (parm));
3581 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3582 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3584 DECL_ARTIFICIAL (decl) = 1;
3585 SET_DECL_TEMPLATE_PARM_P (decl);
3587 parm = build_tree_list (defval, parm);
3588 return chainon (list, parm);
3591 /* The end of a template parameter list has been reached. Process the
3592 tree list into a parameter vector, converting each parameter into a more
3593 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3597 end_template_parm_list (tree parms)
3601 tree saved_parmlist = make_tree_vec (list_length (parms));
3603 current_template_parms
3604 = tree_cons (size_int (processing_template_decl),
3605 saved_parmlist, current_template_parms);
3607 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3609 next = TREE_CHAIN (parm);
3610 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3611 TREE_CHAIN (parm) = NULL_TREE;
3614 --processing_template_parmlist;
3616 return saved_parmlist;
3619 /* Create a new type almost identical to TYPE but which has the
3620 following differences:
3622 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3623 template sibling parameters of T.
3625 2/ T has a new canonical type that matches the new number
3628 3/ From now on, T is going to be what lookups referring to the
3629 name of TYPE will return. No lookup should return TYPE anymore.
3631 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3633 This is a subroutine of fixup_template_parms. */
3636 fixup_template_type_parm_type (tree type, int num_parms)
3638 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3640 /* This is the decl which name is inserted into the symbol table for
3641 the template parm type. So whenever we lookup the type name, this
3642 is the DECL we get. */
3645 /* Do not fix up the type twice. */
3646 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3649 t = copy_type (type);
3650 decl = TYPE_NAME (t);
3652 TYPE_MAIN_VARIANT (t) = t;
3653 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3654 TYPE_POINTER_TO (t) = 0;
3655 TYPE_REFERENCE_TO (t) = 0;
3657 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3658 TEMPLATE_PARM_LEVEL (orig_idx),
3659 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3662 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3663 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3664 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3666 TYPE_STUB_DECL (t) = decl;
3667 TEMPLATE_TYPE_DECL (t) = decl;
3668 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3669 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3671 /* Update the type associated to the type name stored in the symbol
3672 table. Now, whenever the type name is looked up, the resulting
3673 type is properly fixed up. */
3674 TREE_TYPE (decl) = t;
3676 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3681 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3682 identical to I, but that is fixed up as to:
3684 1/ carry the number of sibling parms (NUM_PARMS) of the template
3685 parm represented by I.
3687 2/ replace all references to template parm types declared before I
3688 (in the same template parm list as I) by references to template
3689 parm types contained in ARGS. ARGS should contain the list of
3690 template parms that have been fixed up so far, in a form suitable
3691 to be passed to tsubst.
3693 This is a subroutine of fixup_template_parms. */
3696 fixup_template_parm_index (tree i, tree args, int num_parms)
3698 tree index, decl, type;
3701 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3702 /* Do not fix up the index twice. */
3703 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3706 decl = TEMPLATE_PARM_DECL (i);
3707 type = TREE_TYPE (decl);
3709 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3710 TEMPLATE_PARM_LEVEL (i),
3711 TEMPLATE_PARM_ORIG_LEVEL (i),
3715 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3716 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3718 type = tsubst (type, args, tf_none, NULL_TREE);
3720 TREE_TYPE (decl) = type;
3721 TREE_TYPE (index) = type;
3727 This is a subroutine of fixup_template_parms.
3729 It computes the canonical type of the type of the template
3730 parameter PARM_DESC and update all references to that type so that
3731 they use the newly computed canonical type. No access check is
3732 performed during the fixup. PARM_DESC is a TREE_LIST which
3733 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3734 default argument of the template parm if any. IDX is the index of
3735 the template parameter, starting at 0. NUM_PARMS is the number of
3736 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3737 TREE_VEC containing the full set of template parameters in a form
3738 suitable to be passed to substs functions as their ARGS
3739 argument. This is what current_template_args returns for a given
3740 template. The innermost vector of args in ARGLIST is the set of
3741 template parms that have been fixed up so far. This function adds
3742 the fixed up parameter into that vector. */
3745 fixup_template_parm (tree parm_desc,
3750 tree parm = TREE_VALUE (parm_desc);
3751 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3753 push_deferring_access_checks (dk_no_check);
3755 if (TREE_CODE (parm) == TYPE_DECL)
3757 /* PARM is a template type parameter. Fix up its type, add
3758 the fixed-up template parm to the vector of fixed-up
3759 template parms so far, and substitute the fixed-up
3760 template parms into the default argument of this
3763 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3764 TREE_TYPE (parm) = t;
3766 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3768 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3770 /* PARM is a template template parameter. This is going to
3772 tree tparms, targs, innermost_args, t;
3775 /* First, fix up the parms of the template template parm
3776 because the parms are involved in defining the new canonical
3777 type of the template template parm. */
3779 /* So we need to substitute the template parm types that have
3780 been fixed up so far into the template parms of this template
3781 template parm. E.g, consider this:
3783 template<class T, template<T u> class TT> class S;
3785 In this case we want to substitute T into the
3786 template parameters of TT.
3788 So let's walk the template parms of PARM here, and
3789 tsubst ARGLIST into into each of the template
3792 /* For this substitution we need to build the full set of
3793 template parameters and use that as arguments for the
3794 tsubsting function. */
3795 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3797 /* This will contain the innermost parms of PARM into which
3798 we have substituted so far. */
3799 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3800 targs = add_to_template_args (arglist, innermost_args);
3801 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3805 parameter = TREE_VEC_ELT (tparms, j);
3807 /* INNERMOST_ARGS needs to have at least the same number
3808 of elements as the index PARAMETER, ortherwise
3809 tsubsting into PARAMETER will result in partially
3810 instantiating it, reducing its tempate parm
3811 level. Let's tactically fill INNERMOST_ARGS for that
3813 TREE_VEC_ELT (innermost_args, j) =
3814 template_parm_to_arg (parameter);
3816 fixup_template_parm (parameter, j,
3817 TREE_VEC_LENGTH (tparms),
3821 /* Now fix up the type of the template template parm. */
3823 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3824 TREE_TYPE (parm) = t;
3826 TREE_VEC_ELT (fixedup_args, idx) =
3827 template_parm_to_arg (parm_desc);
3829 else if (TREE_CODE (parm) == PARM_DECL)
3831 /* PARM is a non-type template parameter. We need to:
3833 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3834 proper number of sibling parameters.
3836 * Make lookups of the template parameter return a reference
3837 to the fixed-up index. No lookup should return references
3838 to the former index anymore.
3840 * Substitute the template parms that got fixed up so far
3842 * into the type of PARM. */
3844 tree index = DECL_INITIAL (parm);
3846 /* PUSHED_DECL is the decl added to the symbol table with
3847 the name of the parameter. E,g:
3849 template<class T, T u> //#0
3850 auto my_function(T t) -> decltype(u); //#1
3852 Here, when looking up u at //#1, we get the decl of u
3853 resulting from the declaration in #0. This is what
3854 PUSHED_DECL is. We need to replace the reference to the
3855 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3856 fixed-up TEMPLATE_PARM_INDEX. */
3857 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3859 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3860 fixup the type of PUSHED_DECL as well and luckily
3861 fixup_template_parm_index does it for us too. */
3862 tree fixed_up_index =
3863 fixup_template_parm_index (index, arglist, num_parms);
3865 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3867 /* Add this fixed up PARM to the template parms we've fixed
3868 up so far and use that to substitute the fixed-up
3869 template parms into the type of PARM. */
3870 TREE_VEC_ELT (fixedup_args, idx) =
3871 template_parm_to_arg (parm_desc);
3872 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3873 tf_none, NULL_TREE);
3876 TREE_PURPOSE (parm_desc) =
3877 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3878 arglist, tf_none, parm);
3880 pop_deferring_access_checks ();
3883 /* Walk the current template parms and properly compute the canonical
3884 types of the dependent types created during
3885 cp_parser_template_parameter_list. */
3888 fixup_template_parms (void)
3895 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3896 if (parameter_vec == NULL_TREE)
3899 num_parms = TREE_VEC_LENGTH (parameter_vec);
3901 /* This vector contains the current innermost template parms that
3902 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3903 to be passed to tsubst* functions as their ARGS argument. */
3904 fixedup_args = make_tree_vec (num_parms);
3906 /* This vector contains the full set of template parms in a form
3907 suitable to be passed to substs functions as their ARGS
3909 arglist = current_template_args ();
3910 arglist = add_outermost_template_args (arglist, fixedup_args);
3912 /* Let's do the proper fixup now. */
3913 for (i = 0; i < num_parms; ++i)
3914 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3915 i, num_parms, arglist);
3918 /* end_template_decl is called after a template declaration is seen. */
3921 end_template_decl (void)
3923 reset_specialization ();
3925 if (! processing_template_decl)
3928 /* This matches the pushlevel in begin_template_parm_list. */
3931 --processing_template_decl;
3932 current_template_parms = TREE_CHAIN (current_template_parms);
3935 /* Takes a TREE_LIST representing a template parameter and convert it
3936 into an argument suitable to be passed to the type substitution
3937 functions. Note that If the TREE_LIST contains an error_mark
3938 node, the returned argument is error_mark_node. */
3941 template_parm_to_arg (tree t)
3945 || TREE_CODE (t) != TREE_LIST)
3948 if (error_operand_p (TREE_VALUE (t)))
3949 return error_mark_node;
3953 if (TREE_CODE (t) == TYPE_DECL
3954 || TREE_CODE (t) == TEMPLATE_DECL)
3958 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3960 /* Turn this argument into a TYPE_ARGUMENT_PACK
3961 with a single element, which expands T. */
3962 tree vec = make_tree_vec (1);
3963 #ifdef ENABLE_CHECKING
3964 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3965 (vec, TREE_VEC_LENGTH (vec));
3967 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3969 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3970 SET_ARGUMENT_PACK_ARGS (t, vec);
3975 t = DECL_INITIAL (t);
3977 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3979 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3980 with a single element, which expands T. */
3981 tree vec = make_tree_vec (1);
3982 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3983 #ifdef ENABLE_CHECKING
3984 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3985 (vec, TREE_VEC_LENGTH (vec));
3987 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3989 t = make_node (NONTYPE_ARGUMENT_PACK);
3990 SET_ARGUMENT_PACK_ARGS (t, vec);
3991 TREE_TYPE (t) = type;
3997 /* Within the declaration of a template, return all levels of template
3998 parameters that apply. The template parameters are represented as
3999 a TREE_VEC, in the form documented in cp-tree.h for template
4003 current_template_args (void)
4006 tree args = NULL_TREE;
4007 int length = TMPL_PARMS_DEPTH (current_template_parms);
4010 /* If there is only one level of template parameters, we do not
4011 create a TREE_VEC of TREE_VECs. Instead, we return a single
4012 TREE_VEC containing the arguments. */
4014 args = make_tree_vec (length);
4016 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4018 tree a = copy_node (TREE_VALUE (header));
4021 TREE_TYPE (a) = NULL_TREE;
4022 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4023 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4025 #ifdef ENABLE_CHECKING
4026 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4030 TREE_VEC_ELT (args, --l) = a;
4035 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4036 /* This can happen for template parms of a template template
4039 template<template<class T, class U> class TT> struct S;
4041 Consider the level of the parms of TT; T and U both have
4042 level 2; TT has no template parm of level 1. So in this case
4043 the first element of full_template_args is NULL_TREE. If we
4044 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4045 of 2. This will make tsubst wrongly consider that T and U
4046 have level 1. Instead, let's create a dummy vector as the
4047 first element of full_template_args so that TMPL_ARG_DEPTH
4048 returns the correct depth for args. */
4049 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4053 /* Update the declared TYPE by doing any lookups which were thought to be
4054 dependent, but are not now that we know the SCOPE of the declarator. */
4057 maybe_update_decl_type (tree orig_type, tree scope)
4059 tree type = orig_type;
4061 if (type == NULL_TREE)
4064 if (TREE_CODE (orig_type) == TYPE_DECL)
4065 type = TREE_TYPE (type);
4067 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4068 && dependent_type_p (type)
4069 /* Don't bother building up the args in this case. */
4070 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4072 /* tsubst in the args corresponding to the template parameters,
4073 including auto if present. Most things will be unchanged, but
4074 make_typename_type and tsubst_qualified_id will resolve
4075 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4076 tree args = current_template_args ();
4077 tree auto_node = type_uses_auto (type);
4081 tree auto_vec = make_tree_vec (1);
4082 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4083 args = add_to_template_args (args, auto_vec);
4085 pushed = push_scope (scope);
4086 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4091 if (type == error_mark_node)
4094 if (TREE_CODE (orig_type) == TYPE_DECL)
4096 if (same_type_p (type, TREE_TYPE (orig_type)))
4099 type = TYPE_NAME (type);
4104 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4105 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4106 a member template. Used by push_template_decl below. */
4109 build_template_decl (tree decl, tree parms, bool member_template_p)
4111 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4112 DECL_TEMPLATE_PARMS (tmpl) = parms;
4113 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4114 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4119 struct template_parm_data
4121 /* The level of the template parameters we are currently
4125 /* The index of the specialization argument we are currently
4129 /* An array whose size is the number of template parameters. The
4130 elements are nonzero if the parameter has been used in any one
4131 of the arguments processed so far. */
4134 /* An array whose size is the number of template arguments. The
4135 elements are nonzero if the argument makes use of template
4136 parameters of this level. */
4137 int* arg_uses_template_parms;
4140 /* Subroutine of push_template_decl used to see if each template
4141 parameter in a partial specialization is used in the explicit
4142 argument list. If T is of the LEVEL given in DATA (which is
4143 treated as a template_parm_data*), then DATA->PARMS is marked
4147 mark_template_parm (tree t, void* data)
4151 struct template_parm_data* tpd = (struct template_parm_data*) data;
4153 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4155 level = TEMPLATE_PARM_LEVEL (t);
4156 idx = TEMPLATE_PARM_IDX (t);
4160 level = TEMPLATE_TYPE_LEVEL (t);
4161 idx = TEMPLATE_TYPE_IDX (t);
4164 if (level == tpd->level)
4166 tpd->parms[idx] = 1;
4167 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4170 /* Return zero so that for_each_template_parm will continue the
4171 traversal of the tree; we want to mark *every* template parm. */
4175 /* Process the partial specialization DECL. */
4178 process_partial_specialization (tree decl)
4180 tree type = TREE_TYPE (decl);
4181 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4182 tree specargs = CLASSTYPE_TI_ARGS (type);
4183 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4184 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4187 int nargs = TREE_VEC_LENGTH (inner_args);
4190 bool did_error_intro = false;
4191 struct template_parm_data tpd;
4192 struct template_parm_data tpd2;
4194 gcc_assert (current_template_parms);
4196 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4197 ntparms = TREE_VEC_LENGTH (inner_parms);
4199 /* We check that each of the template parameters given in the
4200 partial specialization is used in the argument list to the
4201 specialization. For example:
4203 template <class T> struct S;
4204 template <class T> struct S<T*>;
4206 The second declaration is OK because `T*' uses the template
4207 parameter T, whereas
4209 template <class T> struct S<int>;
4211 is no good. Even trickier is:
4222 The S2<T> declaration is actually invalid; it is a
4223 full-specialization. Of course,
4226 struct S2<T (*)(U)>;
4228 or some such would have been OK. */
4229 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4230 tpd.parms = XALLOCAVEC (int, ntparms);
4231 memset (tpd.parms, 0, sizeof (int) * ntparms);
4233 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4234 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4235 for (i = 0; i < nargs; ++i)
4237 tpd.current_arg = i;
4238 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4239 &mark_template_parm,
4242 /*include_nondeduced_p=*/false);
4244 for (i = 0; i < ntparms; ++i)
4245 if (tpd.parms[i] == 0)
4247 /* One of the template parms was not used in the
4249 if (!did_error_intro)
4251 error ("template parameters not used in partial specialization:");
4252 did_error_intro = true;
4255 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4258 if (did_error_intro)
4259 return error_mark_node;
4261 /* [temp.class.spec]
4263 The argument list of the specialization shall not be identical to
4264 the implicit argument list of the primary template. */
4265 if (comp_template_args
4267 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4269 error ("partial specialization %qT does not specialize any template arguments", type);
4271 /* [temp.class.spec]
4273 A partially specialized non-type argument expression shall not
4274 involve template parameters of the partial specialization except
4275 when the argument expression is a simple identifier.
4277 The type of a template parameter corresponding to a specialized
4278 non-type argument shall not be dependent on a parameter of the
4281 Also, we verify that pack expansions only occur at the
4282 end of the argument list. */
4283 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4285 for (i = 0; i < nargs; ++i)
4287 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4288 tree arg = TREE_VEC_ELT (inner_args, i);
4289 tree packed_args = NULL_TREE;
4292 if (ARGUMENT_PACK_P (arg))
4294 /* Extract the arguments from the argument pack. We'll be
4295 iterating over these in the following loop. */
4296 packed_args = ARGUMENT_PACK_ARGS (arg);
4297 len = TREE_VEC_LENGTH (packed_args);
4300 for (j = 0; j < len; j++)
4303 /* Get the Jth argument in the parameter pack. */
4304 arg = TREE_VEC_ELT (packed_args, j);
4306 if (PACK_EXPANSION_P (arg))
4308 /* Pack expansions must come at the end of the
4310 if ((packed_args && j < len - 1)
4311 || (!packed_args && i < nargs - 1))
4313 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4314 error ("parameter pack argument %qE must be at the "
4315 "end of the template argument list", arg);
4317 error ("parameter pack argument %qT must be at the "
4318 "end of the template argument list", arg);
4322 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4323 /* We only care about the pattern. */
4324 arg = PACK_EXPANSION_PATTERN (arg);
4326 if (/* These first two lines are the `non-type' bit. */
4328 && TREE_CODE (arg) != TEMPLATE_DECL
4329 /* This next line is the `argument expression is not just a
4330 simple identifier' condition and also the `specialized
4331 non-type argument' bit. */
4332 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4334 if ((!packed_args && tpd.arg_uses_template_parms[i])
4335 || (packed_args && uses_template_parms (arg)))
4336 error ("template argument %qE involves template parameter(s)",
4340 /* Look at the corresponding template parameter,
4341 marking which template parameters its type depends
4343 tree type = TREE_TYPE (parm);
4347 /* We haven't yet initialized TPD2. Do so now. */
4348 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4349 /* The number of parameters here is the number in the
4350 main template, which, as checked in the assertion
4352 tpd2.parms = XALLOCAVEC (int, nargs);
4354 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4357 /* Mark the template parameters. But this time, we're
4358 looking for the template parameters of the main
4359 template, not in the specialization. */
4360 tpd2.current_arg = i;
4361 tpd2.arg_uses_template_parms[i] = 0;
4362 memset (tpd2.parms, 0, sizeof (int) * nargs);
4363 for_each_template_parm (type,
4364 &mark_template_parm,
4367 /*include_nondeduced_p=*/false);
4369 if (tpd2.arg_uses_template_parms [i])
4371 /* The type depended on some template parameters.
4372 If they are fully specialized in the
4373 specialization, that's OK. */
4376 for (j = 0; j < nargs; ++j)
4377 if (tpd2.parms[j] != 0
4378 && tpd.arg_uses_template_parms [j])
4381 error_n (input_location, count,
4382 "type %qT of template argument %qE depends "
4383 "on a template parameter",
4384 "type %qT of template argument %qE depends "
4385 "on template parameters",
4394 /* We should only get here once. */
4395 gcc_assert (!COMPLETE_TYPE_P (type));
4397 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4398 = tree_cons (specargs, inner_parms,
4399 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4400 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4402 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4403 inst = TREE_CHAIN (inst))
4405 tree inst_type = TREE_VALUE (inst);
4406 if (COMPLETE_TYPE_P (inst_type)
4407 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4409 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4410 if (spec && TREE_TYPE (spec) == type)
4411 permerror (input_location,
4412 "partial specialization of %qT after instantiation "
4413 "of %qT", type, inst_type);
4420 /* Check that a template declaration's use of default arguments and
4421 parameter packs is not invalid. Here, PARMS are the template
4422 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4423 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4427 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4428 declaration (but not a definition); 1 indicates a declaration, 2
4429 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4430 emitted for extraneous default arguments.
4432 Returns TRUE if there were no errors found, FALSE otherwise. */
4435 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4436 int is_partial, int is_friend_decl)
4439 int last_level_to_check;
4441 bool no_errors = true;
4445 A default template-argument shall not be specified in a
4446 function template declaration or a function template definition, nor
4447 in the template-parameter-list of the definition of a member of a
4450 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4451 /* You can't have a function template declaration in a local
4452 scope, nor you can you define a member of a class template in a
4456 if (current_class_type
4457 && !TYPE_BEING_DEFINED (current_class_type)
4458 && DECL_LANG_SPECIFIC (decl)
4459 && DECL_DECLARES_FUNCTION_P (decl)
4460 /* If this is either a friend defined in the scope of the class
4461 or a member function. */
4462 && (DECL_FUNCTION_MEMBER_P (decl)
4463 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4464 : DECL_FRIEND_CONTEXT (decl)
4465 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4467 /* And, if it was a member function, it really was defined in
4468 the scope of the class. */
4469 && (!DECL_FUNCTION_MEMBER_P (decl)
4470 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4471 /* We already checked these parameters when the template was
4472 declared, so there's no need to do it again now. This function
4473 was defined in class scope, but we're processing it's body now
4474 that the class is complete. */
4477 /* Core issue 226 (C++0x only): the following only applies to class
4479 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4483 If a template-parameter has a default template-argument, all
4484 subsequent template-parameters shall have a default
4485 template-argument supplied. */
4486 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4488 tree inner_parms = TREE_VALUE (parm_level);
4489 int ntparms = TREE_VEC_LENGTH (inner_parms);
4490 int seen_def_arg_p = 0;
4493 for (i = 0; i < ntparms; ++i)
4495 tree parm = TREE_VEC_ELT (inner_parms, i);
4497 if (parm == error_mark_node)
4500 if (TREE_PURPOSE (parm))
4502 else if (seen_def_arg_p
4503 && !template_parameter_pack_p (TREE_VALUE (parm)))
4505 error ("no default argument for %qD", TREE_VALUE (parm));
4506 /* For better subsequent error-recovery, we indicate that
4507 there should have been a default argument. */
4508 TREE_PURPOSE (parm) = error_mark_node;
4514 /* Don't complain about an enclosing partial
4516 && parm_level == parms
4517 && TREE_CODE (decl) == TYPE_DECL
4519 && template_parameter_pack_p (TREE_VALUE (parm)))
4521 /* A primary class template can only have one
4522 parameter pack, at the end of the template
4525 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4526 error ("parameter pack %qE must be at the end of the"
4527 " template parameter list", TREE_VALUE (parm));
4529 error ("parameter pack %qT must be at the end of the"
4530 " template parameter list",
4531 TREE_TYPE (TREE_VALUE (parm)));
4533 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4541 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4545 /* For an ordinary class template, default template arguments are
4546 allowed at the innermost level, e.g.:
4547 template <class T = int>
4549 but, in a partial specialization, they're not allowed even
4550 there, as we have in [temp.class.spec]:
4552 The template parameter list of a specialization shall not
4553 contain default template argument values.
4555 So, for a partial specialization, or for a function template
4556 (in C++98/C++03), we look at all of them. */
4559 /* But, for a primary class template that is not a partial
4560 specialization we look at all template parameters except the
4562 parms = TREE_CHAIN (parms);
4564 /* Figure out what error message to issue. */
4565 if (is_friend_decl == 2)
4566 msg = G_("default template arguments may not be used in function template "
4567 "friend re-declaration");
4568 else if (is_friend_decl)
4569 msg = G_("default template arguments may not be used in function template "
4570 "friend declarations");
4571 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4572 msg = G_("default template arguments may not be used in function templates "
4573 "without -std=c++0x or -std=gnu++0x");
4574 else if (is_partial)
4575 msg = G_("default template arguments may not be used in "
4576 "partial specializations");
4578 msg = G_("default argument for template parameter for class enclosing %qD");
4580 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4581 /* If we're inside a class definition, there's no need to
4582 examine the parameters to the class itself. On the one
4583 hand, they will be checked when the class is defined, and,
4584 on the other, default arguments are valid in things like:
4585 template <class T = double>
4586 struct S { template <class U> void f(U); };
4587 Here the default argument for `S' has no bearing on the
4588 declaration of `f'. */
4589 last_level_to_check = template_class_depth (current_class_type) + 1;
4591 /* Check everything. */
4592 last_level_to_check = 0;
4594 for (parm_level = parms;
4595 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4596 parm_level = TREE_CHAIN (parm_level))
4598 tree inner_parms = TREE_VALUE (parm_level);
4602 ntparms = TREE_VEC_LENGTH (inner_parms);
4603 for (i = 0; i < ntparms; ++i)
4605 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4608 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4613 if (is_friend_decl == 2)
4620 /* Clear out the default argument so that we are not
4622 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4626 /* At this point, if we're still interested in issuing messages,
4627 they must apply to classes surrounding the object declared. */
4629 msg = G_("default argument for template parameter for class "
4636 /* Worker for push_template_decl_real, called via
4637 for_each_template_parm. DATA is really an int, indicating the
4638 level of the parameters we are interested in. If T is a template
4639 parameter of that level, return nonzero. */
4642 template_parm_this_level_p (tree t, void* data)
4644 int this_level = *(int *)data;
4647 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4648 level = TEMPLATE_PARM_LEVEL (t);
4650 level = TEMPLATE_TYPE_LEVEL (t);
4651 return level == this_level;
4654 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4655 parameters given by current_template_args, or reuses a
4656 previously existing one, if appropriate. Returns the DECL, or an
4657 equivalent one, if it is replaced via a call to duplicate_decls.
4659 If IS_FRIEND is true, DECL is a friend declaration. */
4662 push_template_decl_real (tree decl, bool is_friend)
4670 int new_template_p = 0;
4671 /* True if the template is a member template, in the sense of
4673 bool member_template_p = false;
4675 if (decl == error_mark_node || !current_template_parms)
4676 return error_mark_node;
4678 /* See if this is a partial specialization. */
4679 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4680 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4681 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4683 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4687 /* For a friend, we want the context of the friend function, not
4688 the type of which it is a friend. */
4689 ctx = CP_DECL_CONTEXT (decl);
4690 else if (CP_DECL_CONTEXT (decl)
4691 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4692 /* In the case of a virtual function, we want the class in which
4694 ctx = CP_DECL_CONTEXT (decl);
4696 /* Otherwise, if we're currently defining some class, the DECL
4697 is assumed to be a member of the class. */
4698 ctx = current_scope ();
4700 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4703 if (!DECL_CONTEXT (decl))
4704 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4706 /* See if this is a primary template. */
4707 if (is_friend && ctx)
4708 /* A friend template that specifies a class context, i.e.
4709 template <typename T> friend void A<T>::f();
4713 primary = template_parm_scope_p ();
4717 if (DECL_CLASS_SCOPE_P (decl))
4718 member_template_p = true;
4719 if (TREE_CODE (decl) == TYPE_DECL
4720 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4722 error ("template class without a name");
4723 return error_mark_node;
4725 else if (TREE_CODE (decl) == FUNCTION_DECL)
4727 if (DECL_DESTRUCTOR_P (decl))
4731 A destructor shall not be a member template. */
4732 error ("destructor %qD declared as member template", decl);
4733 return error_mark_node;
4735 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4736 && (!prototype_p (TREE_TYPE (decl))
4737 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4738 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4739 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4740 == void_list_node)))
4742 /* [basic.stc.dynamic.allocation]
4744 An allocation function can be a function
4745 template. ... Template allocation functions shall
4746 have two or more parameters. */
4747 error ("invalid template declaration of %qD", decl);
4748 return error_mark_node;
4751 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4752 && CLASS_TYPE_P (TREE_TYPE (decl)))
4756 error ("template declaration of %q#D", decl);
4757 return error_mark_node;
4761 /* Check to see that the rules regarding the use of default
4762 arguments are not being violated. */
4763 check_default_tmpl_args (decl, current_template_parms,
4764 primary, is_partial, /*is_friend_decl=*/0);
4766 /* Ensure that there are no parameter packs in the type of this
4767 declaration that have not been expanded. */
4768 if (TREE_CODE (decl) == FUNCTION_DECL)
4770 /* Check each of the arguments individually to see if there are
4771 any bare parameter packs. */
4772 tree type = TREE_TYPE (decl);
4773 tree arg = DECL_ARGUMENTS (decl);
4774 tree argtype = TYPE_ARG_TYPES (type);
4776 while (arg && argtype)
4778 if (!FUNCTION_PARAMETER_PACK_P (arg)
4779 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4781 /* This is a PARM_DECL that contains unexpanded parameter
4782 packs. We have already complained about this in the
4783 check_for_bare_parameter_packs call, so just replace
4784 these types with ERROR_MARK_NODE. */
4785 TREE_TYPE (arg) = error_mark_node;
4786 TREE_VALUE (argtype) = error_mark_node;
4789 arg = DECL_CHAIN (arg);
4790 argtype = TREE_CHAIN (argtype);
4793 /* Check for bare parameter packs in the return type and the
4794 exception specifiers. */
4795 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4796 /* Errors were already issued, set return type to int
4797 as the frontend doesn't expect error_mark_node as
4799 TREE_TYPE (type) = integer_type_node;
4800 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4801 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4803 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4805 TREE_TYPE (decl) = error_mark_node;
4806 return error_mark_node;
4810 return process_partial_specialization (decl);
4812 args = current_template_args ();
4815 || TREE_CODE (ctx) == FUNCTION_DECL
4816 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4817 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4819 if (DECL_LANG_SPECIFIC (decl)
4820 && DECL_TEMPLATE_INFO (decl)
4821 && DECL_TI_TEMPLATE (decl))
4822 tmpl = DECL_TI_TEMPLATE (decl);
4823 /* If DECL is a TYPE_DECL for a class-template, then there won't
4824 be DECL_LANG_SPECIFIC. The information equivalent to
4825 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4826 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4827 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4828 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4830 /* Since a template declaration already existed for this
4831 class-type, we must be redeclaring it here. Make sure
4832 that the redeclaration is valid. */
4833 redeclare_class_template (TREE_TYPE (decl),
4834 current_template_parms);
4835 /* We don't need to create a new TEMPLATE_DECL; just use the
4836 one we already had. */
4837 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4841 tmpl = build_template_decl (decl, current_template_parms,
4845 if (DECL_LANG_SPECIFIC (decl)
4846 && DECL_TEMPLATE_SPECIALIZATION (decl))
4848 /* A specialization of a member template of a template
4850 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4851 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4852 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4858 tree a, t, current, parms;
4860 tree tinfo = get_template_info (decl);
4864 error ("template definition of non-template %q#D", decl);
4865 return error_mark_node;
4868 tmpl = TI_TEMPLATE (tinfo);
4870 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4871 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4872 && DECL_TEMPLATE_SPECIALIZATION (decl)
4873 && DECL_MEMBER_TEMPLATE_P (tmpl))
4877 /* The declaration is a specialization of a member
4878 template, declared outside the class. Therefore, the
4879 innermost template arguments will be NULL, so we
4880 replace them with the arguments determined by the
4881 earlier call to check_explicit_specialization. */
4882 args = DECL_TI_ARGS (decl);
4885 = build_template_decl (decl, current_template_parms,
4887 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4888 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4889 DECL_TI_TEMPLATE (decl) = new_tmpl;
4890 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4891 DECL_TEMPLATE_INFO (new_tmpl)
4892 = build_template_info (tmpl, args);
4894 register_specialization (new_tmpl,
4895 most_general_template (tmpl),
4901 /* Make sure the template headers we got make sense. */
4903 parms = DECL_TEMPLATE_PARMS (tmpl);
4904 i = TMPL_PARMS_DEPTH (parms);
4905 if (TMPL_ARGS_DEPTH (args) != i)
4907 error ("expected %d levels of template parms for %q#D, got %d",
4908 i, decl, TMPL_ARGS_DEPTH (args));
4911 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4913 a = TMPL_ARGS_LEVEL (args, i);
4914 t = INNERMOST_TEMPLATE_PARMS (parms);
4916 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4918 if (current == decl)
4919 error ("got %d template parameters for %q#D",
4920 TREE_VEC_LENGTH (a), decl);
4922 error ("got %d template parameters for %q#T",
4923 TREE_VEC_LENGTH (a), current);
4924 error (" but %d required", TREE_VEC_LENGTH (t));
4925 return error_mark_node;
4928 if (current == decl)
4930 else if (current == NULL_TREE)
4931 /* Can happen in erroneous input. */
4934 current = (TYPE_P (current)
4935 ? TYPE_CONTEXT (current)
4936 : DECL_CONTEXT (current));
4939 /* Check that the parms are used in the appropriate qualifying scopes
4940 in the declarator. */
4941 if (!comp_template_args
4943 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4946 template arguments to %qD do not match original template %qD",
4947 decl, DECL_TEMPLATE_RESULT (tmpl));
4948 if (!uses_template_parms (TI_ARGS (tinfo)))
4949 inform (input_location, "use template<> for an explicit specialization");
4950 /* Avoid crash in import_export_decl. */
4951 DECL_INTERFACE_KNOWN (decl) = 1;
4952 return error_mark_node;
4956 DECL_TEMPLATE_RESULT (tmpl) = decl;
4957 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4959 /* Push template declarations for global functions and types. Note
4960 that we do not try to push a global template friend declared in a
4961 template class; such a thing may well depend on the template
4962 parameters of the class. */
4963 if (new_template_p && !ctx
4964 && !(is_friend && template_class_depth (current_class_type) > 0))
4966 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4967 if (tmpl == error_mark_node)
4968 return error_mark_node;
4970 /* Hide template friend classes that haven't been declared yet. */
4971 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4973 DECL_ANTICIPATED (tmpl) = 1;
4974 DECL_FRIEND_P (tmpl) = 1;
4980 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4983 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4984 if (DECL_CONV_FN_P (tmpl))
4986 int depth = TMPL_PARMS_DEPTH (parms);
4988 /* It is a conversion operator. See if the type converted to
4989 depends on innermost template operands. */
4991 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4993 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4996 /* Give template template parms a DECL_CONTEXT of the template
4997 for which they are a parameter. */
4998 parms = INNERMOST_TEMPLATE_PARMS (parms);
4999 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5001 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5002 if (TREE_CODE (parm) == TEMPLATE_DECL)
5003 DECL_CONTEXT (parm) = tmpl;
5007 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5008 back to its most general template. If TMPL is a specialization,
5009 ARGS may only have the innermost set of arguments. Add the missing
5010 argument levels if necessary. */
5011 if (DECL_TEMPLATE_INFO (tmpl))
5012 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5014 info = build_template_info (tmpl, args);
5016 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5017 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5018 else if (DECL_LANG_SPECIFIC (decl))
5019 DECL_TEMPLATE_INFO (decl) = info;
5021 return DECL_TEMPLATE_RESULT (tmpl);
5025 push_template_decl (tree decl)
5027 return push_template_decl_real (decl, false);
5030 /* Called when a class template TYPE is redeclared with the indicated
5031 template PARMS, e.g.:
5033 template <class T> struct S;
5034 template <class T> struct S {}; */
5037 redeclare_class_template (tree type, tree parms)
5043 if (!TYPE_TEMPLATE_INFO (type))
5045 error ("%qT is not a template type", type);
5049 tmpl = TYPE_TI_TEMPLATE (type);
5050 if (!PRIMARY_TEMPLATE_P (tmpl))
5051 /* The type is nested in some template class. Nothing to worry
5052 about here; there are no new template parameters for the nested
5058 error ("template specifiers not specified in declaration of %qD",
5063 parms = INNERMOST_TEMPLATE_PARMS (parms);
5064 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5066 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5068 error_n (input_location, TREE_VEC_LENGTH (parms),
5069 "redeclared with %d template parameter",
5070 "redeclared with %d template parameters",
5071 TREE_VEC_LENGTH (parms));
5072 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5073 "previous declaration %q+D used %d template parameter",
5074 "previous declaration %q+D used %d template parameters",
5075 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5079 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5086 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5087 || TREE_VEC_ELT (parms, i) == error_mark_node)
5090 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5091 if (tmpl_parm == error_mark_node)
5094 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5095 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5096 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5098 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5100 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5101 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5102 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5103 || (TREE_CODE (tmpl_parm) != PARM_DECL
5104 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5105 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5106 || (TREE_CODE (tmpl_parm) == PARM_DECL
5107 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5108 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5110 error ("template parameter %q+#D", tmpl_parm);
5111 error ("redeclared here as %q#D", parm);
5115 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5117 /* We have in [temp.param]:
5119 A template-parameter may not be given default arguments
5120 by two different declarations in the same scope. */
5121 error_at (input_location, "redefinition of default argument for %q#D", parm);
5122 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5123 "original definition appeared here");
5127 if (parm_default != NULL_TREE)
5128 /* Update the previous template parameters (which are the ones
5129 that will really count) with the new default value. */
5130 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5131 else if (tmpl_default != NULL_TREE)
5132 /* Update the new parameters, too; they'll be used as the
5133 parameters for any members. */
5134 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5140 /* Simplify EXPR if it is a non-dependent expression. Returns the
5141 (possibly simplified) expression. */
5144 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5146 if (expr == NULL_TREE)
5149 /* If we're in a template, but EXPR isn't value dependent, simplify
5150 it. We're supposed to treat:
5152 template <typename T> void f(T[1 + 1]);
5153 template <typename T> void f(T[2]);
5155 as two declarations of the same function, for example. */
5156 if (processing_template_decl
5157 && !type_dependent_expression_p (expr)
5158 && potential_constant_expression (expr)
5159 && !value_dependent_expression_p (expr))
5161 HOST_WIDE_INT saved_processing_template_decl;
5163 saved_processing_template_decl = processing_template_decl;
5164 processing_template_decl = 0;
5165 expr = tsubst_copy_and_build (expr,
5168 /*in_decl=*/NULL_TREE,
5169 /*function_p=*/false,
5170 /*integral_constant_expression_p=*/true);
5171 processing_template_decl = saved_processing_template_decl;
5177 fold_non_dependent_expr (tree expr)
5179 return fold_non_dependent_expr_sfinae (expr, tf_error);
5182 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5183 must be a function or a pointer-to-function type, as specified
5184 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5185 and check that the resulting function has external linkage. */
5188 convert_nontype_argument_function (tree type, tree expr)
5193 fn = instantiate_type (type, fns, tf_none);
5194 if (fn == error_mark_node)
5195 return error_mark_node;
5198 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5199 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5200 if (TREE_CODE (fn_no_ptr) == BASELINK)
5201 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5203 /* [temp.arg.nontype]/1
5205 A template-argument for a non-type, non-template template-parameter
5208 -- the address of an object or function with external linkage. */
5209 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5211 error ("%qE is not a valid template argument for type %qT "
5212 "because function %qD has not external linkage",
5213 expr, type, fn_no_ptr);
5220 /* Subroutine of convert_nontype_argument.
5221 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5222 Emit an error otherwise. */
5225 check_valid_ptrmem_cst_expr (tree type, tree expr,
5226 tsubst_flags_t complain)
5229 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5231 if (complain & tf_error)
5233 error ("%qE is not a valid template argument for type %qT",
5235 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5240 /* Returns TRUE iff the address of OP is value-dependent.
5242 14.6.2.4 [temp.dep.temp]:
5243 A non-integral non-type template-argument is dependent if its type is
5244 dependent or it has either of the following forms
5247 and contains a nested-name-specifier which specifies a class-name that
5248 names a dependent type.
5250 We generalize this to just say that the address of a member of a
5251 dependent class is value-dependent; the above doesn't cover the
5252 address of a static data member named with an unqualified-id. */
5255 has_value_dependent_address (tree op)
5257 /* We could use get_inner_reference here, but there's no need;
5258 this is only relevant for template non-type arguments, which
5259 can only be expressed as &id-expression. */
5262 tree ctx = CP_DECL_CONTEXT (op);
5263 if (TYPE_P (ctx) && dependent_type_p (ctx))
5270 /* Attempt to convert the non-type template parameter EXPR to the
5271 indicated TYPE. If the conversion is successful, return the
5272 converted value. If the conversion is unsuccessful, return
5273 NULL_TREE if we issued an error message, or error_mark_node if we
5274 did not. We issue error messages for out-and-out bad template
5275 parameters, but not simply because the conversion failed, since we
5276 might be just trying to do argument deduction. Both TYPE and EXPR
5277 must be non-dependent.
5279 The conversion follows the special rules described in
5280 [temp.arg.nontype], and it is much more strict than an implicit
5283 This function is called twice for each template argument (see
5284 lookup_template_class for a more accurate description of this
5285 problem). This means that we need to handle expressions which
5286 are not valid in a C++ source, but can be created from the
5287 first call (for instance, casts to perform conversions). These
5288 hacks can go away after we fix the double coercion problem. */
5291 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5295 /* Detect immediately string literals as invalid non-type argument.
5296 This special-case is not needed for correctness (we would easily
5297 catch this later), but only to provide better diagnostic for this
5298 common user mistake. As suggested by DR 100, we do not mention
5299 linkage issues in the diagnostic as this is not the point. */
5300 /* FIXME we're making this OK. */
5301 if (TREE_CODE (expr) == STRING_CST)
5303 if (complain & tf_error)
5304 error ("%qE is not a valid template argument for type %qT "
5305 "because string literals can never be used in this context",
5310 /* Add the ADDR_EXPR now for the benefit of
5311 value_dependent_expression_p. */
5312 if (TYPE_PTROBV_P (type)
5313 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5314 expr = decay_conversion (expr);
5316 /* If we are in a template, EXPR may be non-dependent, but still
5317 have a syntactic, rather than semantic, form. For example, EXPR
5318 might be a SCOPE_REF, rather than the VAR_DECL to which the
5319 SCOPE_REF refers. Preserving the qualifying scope is necessary
5320 so that access checking can be performed when the template is
5321 instantiated -- but here we need the resolved form so that we can
5322 convert the argument. */
5323 if (TYPE_REF_OBJ_P (type)
5324 && has_value_dependent_address (expr))
5325 /* If we want the address and it's value-dependent, don't fold. */;
5326 else if (!type_unknown_p (expr))
5327 expr = fold_non_dependent_expr_sfinae (expr, complain);
5328 if (error_operand_p (expr))
5329 return error_mark_node;
5330 expr_type = TREE_TYPE (expr);
5331 if (TREE_CODE (type) == REFERENCE_TYPE)
5332 expr = mark_lvalue_use (expr);
5334 expr = mark_rvalue_use (expr);
5336 /* HACK: Due to double coercion, we can get a
5337 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5338 which is the tree that we built on the first call (see
5339 below when coercing to reference to object or to reference to
5340 function). We just strip everything and get to the arg.
5341 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5343 if (TREE_CODE (expr) == NOP_EXPR)
5345 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5347 /* ??? Maybe we could use convert_from_reference here, but we
5348 would need to relax its constraints because the NOP_EXPR
5349 could actually change the type to something more cv-qualified,
5350 and this is not folded by convert_from_reference. */
5351 tree addr = TREE_OPERAND (expr, 0);
5352 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
5353 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5354 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5355 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5356 (TREE_TYPE (expr_type),
5357 TREE_TYPE (TREE_TYPE (addr))));
5359 expr = TREE_OPERAND (addr, 0);
5360 expr_type = TREE_TYPE (expr);
5363 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5364 parameter is a pointer to object, through decay and
5365 qualification conversion. Let's strip everything. */
5366 else if (TYPE_PTROBV_P (type))
5369 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5370 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5371 /* Skip the ADDR_EXPR only if it is part of the decay for
5372 an array. Otherwise, it is part of the original argument
5373 in the source code. */
5374 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5375 expr = TREE_OPERAND (expr, 0);
5376 expr_type = TREE_TYPE (expr);
5380 /* [temp.arg.nontype]/5, bullet 1
5382 For a non-type template-parameter of integral or enumeration type,
5383 integral promotions (_conv.prom_) and integral conversions
5384 (_conv.integral_) are applied. */
5385 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5387 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5388 t = maybe_constant_value (t);
5389 if (t != error_mark_node)
5392 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5393 return error_mark_node;
5395 /* Notice that there are constant expressions like '4 % 0' which
5396 do not fold into integer constants. */
5397 if (TREE_CODE (expr) != INTEGER_CST)
5399 if (complain & tf_error)
5401 int errs = errorcount, warns = warningcount;
5402 expr = cxx_constant_value (expr);
5403 if (errorcount > errs || warningcount > warns)
5404 inform (EXPR_LOC_OR_HERE (expr),
5405 "in template argument for type %qT ", type);
5406 if (expr == error_mark_node)
5408 /* else cxx_constant_value complained but gave us
5409 a real constant, so go ahead. */
5410 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5416 /* [temp.arg.nontype]/5, bullet 2
5418 For a non-type template-parameter of type pointer to object,
5419 qualification conversions (_conv.qual_) and the array-to-pointer
5420 conversion (_conv.array_) are applied. */
5421 else if (TYPE_PTROBV_P (type))
5423 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5425 A template-argument for a non-type, non-template template-parameter
5426 shall be one of: [...]
5428 -- the name of a non-type template-parameter;
5429 -- the address of an object or function with external linkage, [...]
5430 expressed as "& id-expression" where the & is optional if the name
5431 refers to a function or array, or if the corresponding
5432 template-parameter is a reference.
5434 Here, we do not care about functions, as they are invalid anyway
5435 for a parameter of type pointer-to-object. */
5437 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5438 /* Non-type template parameters are OK. */
5440 else if (TREE_CODE (expr) != ADDR_EXPR
5441 && TREE_CODE (expr_type) != ARRAY_TYPE)
5443 if (TREE_CODE (expr) == VAR_DECL)
5445 error ("%qD is not a valid template argument "
5446 "because %qD is a variable, not the address of "
5451 /* Other values, like integer constants, might be valid
5452 non-type arguments of some other type. */
5453 return error_mark_node;
5459 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5460 ? TREE_OPERAND (expr, 0) : expr);
5461 if (TREE_CODE (decl) != VAR_DECL)
5463 error ("%qE is not a valid template argument of type %qT "
5464 "because %qE is not a variable",
5468 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5470 error ("%qE is not a valid template argument of type %qT "
5471 "because %qD does not have external linkage",
5477 expr = decay_conversion (expr);
5478 if (expr == error_mark_node)
5479 return error_mark_node;
5481 expr = perform_qualification_conversions (type, expr);
5482 if (expr == error_mark_node)
5483 return error_mark_node;
5485 /* [temp.arg.nontype]/5, bullet 3
5487 For a non-type template-parameter of type reference to object, no
5488 conversions apply. The type referred to by the reference may be more
5489 cv-qualified than the (otherwise identical) type of the
5490 template-argument. The template-parameter is bound directly to the
5491 template-argument, which must be an lvalue. */
5492 else if (TYPE_REF_OBJ_P (type))
5494 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5496 return error_mark_node;
5498 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5500 error ("%qE is not a valid template argument for type %qT "
5501 "because of conflicts in cv-qualification", expr, type);
5505 if (!real_lvalue_p (expr))
5507 error ("%qE is not a valid template argument for type %qT "
5508 "because it is not an lvalue", expr, type);
5512 /* [temp.arg.nontype]/1
5514 A template-argument for a non-type, non-template template-parameter
5515 shall be one of: [...]
5517 -- the address of an object or function with external linkage. */
5518 if (TREE_CODE (expr) == INDIRECT_REF
5519 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5521 expr = TREE_OPERAND (expr, 0);
5524 error ("%q#D is not a valid template argument for type %qT "
5525 "because a reference variable does not have a constant "
5526 "address", expr, type);
5533 error ("%qE is not a valid template argument for type %qT "
5534 "because it is not an object with external linkage",
5539 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5541 error ("%qE is not a valid template argument for type %qT "
5542 "because object %qD has not external linkage",
5547 expr = build_nop (type, build_address (expr));
5549 /* [temp.arg.nontype]/5, bullet 4
5551 For a non-type template-parameter of type pointer to function, only
5552 the function-to-pointer conversion (_conv.func_) is applied. If the
5553 template-argument represents a set of overloaded functions (or a
5554 pointer to such), the matching function is selected from the set
5556 else if (TYPE_PTRFN_P (type))
5558 /* If the argument is a template-id, we might not have enough
5559 context information to decay the pointer. */
5560 if (!type_unknown_p (expr_type))
5562 expr = decay_conversion (expr);
5563 if (expr == error_mark_node)
5564 return error_mark_node;
5567 expr = convert_nontype_argument_function (type, expr);
5568 if (!expr || expr == error_mark_node)
5571 if (TREE_CODE (expr) != ADDR_EXPR)
5573 error ("%qE is not a valid template argument for type %qT", expr, type);
5574 error ("it must be the address of a function with external linkage");
5578 /* [temp.arg.nontype]/5, bullet 5
5580 For a non-type template-parameter of type reference to function, no
5581 conversions apply. If the template-argument represents a set of
5582 overloaded functions, the matching function is selected from the set
5584 else if (TYPE_REFFN_P (type))
5586 if (TREE_CODE (expr) == ADDR_EXPR)
5588 error ("%qE is not a valid template argument for type %qT "
5589 "because it is a pointer", expr, type);
5590 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5594 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5595 if (!expr || expr == error_mark_node)
5598 expr = build_nop (type, build_address (expr));
5600 /* [temp.arg.nontype]/5, bullet 6
5602 For a non-type template-parameter of type pointer to member function,
5603 no conversions apply. If the template-argument represents a set of
5604 overloaded member functions, the matching member function is selected
5605 from the set (_over.over_). */
5606 else if (TYPE_PTRMEMFUNC_P (type))
5608 expr = instantiate_type (type, expr, tf_none);
5609 if (expr == error_mark_node)
5610 return error_mark_node;
5612 /* [temp.arg.nontype] bullet 1 says the pointer to member
5613 expression must be a pointer-to-member constant. */
5614 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5615 return error_mark_node;
5617 /* There is no way to disable standard conversions in
5618 resolve_address_of_overloaded_function (called by
5619 instantiate_type). It is possible that the call succeeded by
5620 converting &B::I to &D::I (where B is a base of D), so we need
5621 to reject this conversion here.
5623 Actually, even if there was a way to disable standard conversions,
5624 it would still be better to reject them here so that we can
5625 provide a superior diagnostic. */
5626 if (!same_type_p (TREE_TYPE (expr), type))
5628 error ("%qE is not a valid template argument for type %qT "
5629 "because it is of type %qT", expr, type,
5631 /* If we are just one standard conversion off, explain. */
5632 if (can_convert (type, TREE_TYPE (expr)))
5633 inform (input_location,
5634 "standard conversions are not allowed in this context");
5638 /* [temp.arg.nontype]/5, bullet 7
5640 For a non-type template-parameter of type pointer to data member,
5641 qualification conversions (_conv.qual_) are applied. */
5642 else if (TYPE_PTRMEM_P (type))
5644 /* [temp.arg.nontype] bullet 1 says the pointer to member
5645 expression must be a pointer-to-member constant. */
5646 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5647 return error_mark_node;
5649 expr = perform_qualification_conversions (type, expr);
5650 if (expr == error_mark_node)
5653 /* A template non-type parameter must be one of the above. */
5657 /* Sanity check: did we actually convert the argument to the
5659 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5660 (type, TREE_TYPE (expr)));
5664 /* Subroutine of coerce_template_template_parms, which returns 1 if
5665 PARM_PARM and ARG_PARM match using the rule for the template
5666 parameters of template template parameters. Both PARM and ARG are
5667 template parameters; the rest of the arguments are the same as for
5668 coerce_template_template_parms.
5671 coerce_template_template_parm (tree parm,
5673 tsubst_flags_t complain,
5677 if (arg == NULL_TREE || arg == error_mark_node
5678 || parm == NULL_TREE || parm == error_mark_node)
5681 if (TREE_CODE (arg) != TREE_CODE (parm))
5684 switch (TREE_CODE (parm))
5687 /* We encounter instantiations of templates like
5688 template <template <template <class> class> class TT>
5691 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5692 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5694 if (!coerce_template_template_parms
5695 (parmparm, argparm, complain, in_decl, outer_args))
5701 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5702 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5703 /* Argument is a parameter pack but parameter is not. */
5708 /* The tsubst call is used to handle cases such as
5710 template <int> class C {};
5711 template <class T, template <T> class TT> class D {};
5714 i.e. the parameter list of TT depends on earlier parameters. */
5715 if (!uses_template_parms (TREE_TYPE (arg))
5717 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5721 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5722 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5723 /* Argument is a parameter pack but parameter is not. */
5736 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5737 template template parameters. Both PARM_PARMS and ARG_PARMS are
5738 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5741 Consider the example:
5742 template <class T> class A;
5743 template<template <class U> class TT> class B;
5745 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5746 the parameters to A, and OUTER_ARGS contains A. */
5749 coerce_template_template_parms (tree parm_parms,
5751 tsubst_flags_t complain,
5755 int nparms, nargs, i;
5759 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5760 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5762 nparms = TREE_VEC_LENGTH (parm_parms);
5763 nargs = TREE_VEC_LENGTH (arg_parms);
5765 /* Determine whether we have a parameter pack at the end of the
5766 template template parameter's template parameter list. */
5767 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5769 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5771 if (parm == error_mark_node)
5774 switch (TREE_CODE (parm))
5778 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5783 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5793 && !(variadic_p && nargs >= nparms - 1))
5796 /* Check all of the template parameters except the parameter pack at
5797 the end (if any). */
5798 for (i = 0; i < nparms - variadic_p; ++i)
5800 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5801 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5804 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5805 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5807 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5815 /* Check each of the template parameters in the template
5816 argument against the template parameter pack at the end of
5817 the template template parameter. */
5818 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5821 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5823 for (; i < nargs; ++i)
5825 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5828 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5830 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5839 /* Verifies that the deduced template arguments (in TARGS) for the
5840 template template parameters (in TPARMS) represent valid bindings,
5841 by comparing the template parameter list of each template argument
5842 to the template parameter list of its corresponding template
5843 template parameter, in accordance with DR150. This
5844 routine can only be called after all template arguments have been
5845 deduced. It will return TRUE if all of the template template
5846 parameter bindings are okay, FALSE otherwise. */
5848 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5850 int i, ntparms = TREE_VEC_LENGTH (tparms);
5853 /* We're dealing with template parms in this process. */
5854 ++processing_template_decl;
5856 targs = INNERMOST_TEMPLATE_ARGS (targs);
5858 for (i = 0; i < ntparms; ++i)
5860 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5861 tree targ = TREE_VEC_ELT (targs, i);
5863 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5865 tree packed_args = NULL_TREE;
5868 if (ARGUMENT_PACK_P (targ))
5870 /* Look inside the argument pack. */
5871 packed_args = ARGUMENT_PACK_ARGS (targ);
5872 len = TREE_VEC_LENGTH (packed_args);
5875 for (idx = 0; idx < len; ++idx)
5877 tree targ_parms = NULL_TREE;
5880 /* Extract the next argument from the argument
5882 targ = TREE_VEC_ELT (packed_args, idx);
5884 if (PACK_EXPANSION_P (targ))
5885 /* Look at the pattern of the pack expansion. */
5886 targ = PACK_EXPANSION_PATTERN (targ);
5888 /* Extract the template parameters from the template
5890 if (TREE_CODE (targ) == TEMPLATE_DECL)
5891 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5892 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5893 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5895 /* Verify that we can coerce the template template
5896 parameters from the template argument to the template
5897 parameter. This requires an exact match. */
5899 && !coerce_template_template_parms
5900 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5915 --processing_template_decl;
5919 /* Convert the indicated template ARG as necessary to match the
5920 indicated template PARM. Returns the converted ARG, or
5921 error_mark_node if the conversion was unsuccessful. Error and
5922 warning messages are issued under control of COMPLAIN. This
5923 conversion is for the Ith parameter in the parameter list. ARGS is
5924 the full set of template arguments deduced so far. */
5927 convert_template_argument (tree parm,
5930 tsubst_flags_t complain,
5936 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5938 if (TREE_CODE (arg) == TREE_LIST
5939 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5941 /* The template argument was the name of some
5942 member function. That's usually
5943 invalid, but static members are OK. In any
5944 case, grab the underlying fields/functions
5945 and issue an error later if required. */
5946 orig_arg = TREE_VALUE (arg);
5947 TREE_TYPE (arg) = unknown_type_node;
5952 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5953 requires_type = (TREE_CODE (parm) == TYPE_DECL
5954 || requires_tmpl_type);
5956 /* When determining whether an argument pack expansion is a template,
5957 look at the pattern. */
5958 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5959 arg = PACK_EXPANSION_PATTERN (arg);
5961 /* Deal with an injected-class-name used as a template template arg. */
5962 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5964 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5965 if (TREE_CODE (t) == TEMPLATE_DECL)
5967 if (cxx_dialect >= cxx0x)
5968 /* OK under DR 1004. */;
5969 else if (complain & tf_warning_or_error)
5970 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5971 " used as template template argument", TYPE_NAME (arg));
5972 else if (flag_pedantic_errors)
5980 ((TREE_CODE (arg) == TEMPLATE_DECL
5981 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5982 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5983 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5986 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5987 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5988 arg = TYPE_STUB_DECL (arg);
5990 is_type = TYPE_P (arg) || is_tmpl_type;
5992 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5993 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5995 permerror (input_location, "to refer to a type member of a template parameter, "
5996 "use %<typename %E%>", orig_arg);
5998 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5999 TREE_OPERAND (arg, 1),
6001 complain & tf_error);
6005 if (is_type != requires_type)
6009 if (complain & tf_error)
6011 error ("type/value mismatch at argument %d in template "
6012 "parameter list for %qD",
6015 error (" expected a constant of type %qT, got %qT",
6017 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6018 else if (requires_tmpl_type)
6019 error (" expected a class template, got %qE", orig_arg);
6021 error (" expected a type, got %qE", orig_arg);
6024 return error_mark_node;
6026 if (is_tmpl_type ^ requires_tmpl_type)
6028 if (in_decl && (complain & tf_error))
6030 error ("type/value mismatch at argument %d in template "
6031 "parameter list for %qD",
6034 error (" expected a type, got %qT", DECL_NAME (arg));
6036 error (" expected a class template, got %qT", orig_arg);
6038 return error_mark_node;
6043 if (requires_tmpl_type)
6045 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6046 /* The number of argument required is not known yet.
6047 Just accept it for now. */
6048 val = TREE_TYPE (arg);
6051 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6054 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6056 if (coerce_template_template_parms (parmparm, argparm,
6062 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6064 if (val != error_mark_node)
6066 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6067 val = TREE_TYPE (val);
6068 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6069 val = make_pack_expansion (val);
6074 if (in_decl && (complain & tf_error))
6076 error ("type/value mismatch at argument %d in "
6077 "template parameter list for %qD",
6079 error (" expected a template of type %qD, got %qT",
6083 val = error_mark_node;
6089 /* We only form one instance of each template specialization.
6090 Therefore, if we use a non-canonical variant (i.e., a
6091 typedef), any future messages referring to the type will use
6092 the typedef, which is confusing if those future uses do not
6093 themselves also use the typedef. */
6095 val = strip_typedefs (val);
6099 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6101 if (invalid_nontype_parm_type_p (t, complain))
6102 return error_mark_node;
6104 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6106 if (same_type_p (t, TREE_TYPE (orig_arg)))
6110 /* Not sure if this is reachable, but it doesn't hurt
6112 error ("type mismatch in nontype parameter pack");
6113 val = error_mark_node;
6116 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6117 /* We used to call digest_init here. However, digest_init
6118 will report errors, which we don't want when complain
6119 is zero. More importantly, digest_init will try too
6120 hard to convert things: for example, `0' should not be
6121 converted to pointer type at this point according to
6122 the standard. Accepting this is not merely an
6123 extension, since deciding whether or not these
6124 conversions can occur is part of determining which
6125 function template to call, or whether a given explicit
6126 argument specification is valid. */
6127 val = convert_nontype_argument (t, orig_arg, complain);
6131 if (val == NULL_TREE)
6132 val = error_mark_node;
6133 else if (val == error_mark_node && (complain & tf_error))
6134 error ("could not convert template argument %qE to %qT", orig_arg, t);
6136 if (TREE_CODE (val) == SCOPE_REF)
6138 /* Strip typedefs from the SCOPE_REF. */
6139 tree type = strip_typedefs (TREE_TYPE (val));
6140 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
6141 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6142 QUALIFIED_NAME_IS_TEMPLATE (val));
6149 /* Coerces the remaining template arguments in INNER_ARGS (from
6150 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6151 Returns the coerced argument pack. PARM_IDX is the position of this
6152 parameter in the template parameter list. ARGS is the original
6153 template argument list. */
6155 coerce_template_parameter_pack (tree parms,
6163 tsubst_flags_t complain)
6165 tree parm = TREE_VEC_ELT (parms, parm_idx);
6166 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6169 tree packed_types = NULL_TREE;
6171 if (arg_idx > nargs)
6174 packed_args = make_tree_vec (nargs - arg_idx);
6176 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6177 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6179 /* When the template parameter is a non-type template
6180 parameter pack whose type uses parameter packs, we need
6181 to look at each of the template arguments
6182 separately. Build a vector of the types for these
6183 non-type template parameters in PACKED_TYPES. */
6185 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6186 packed_types = tsubst_pack_expansion (expansion, args,
6189 if (packed_types == error_mark_node)
6190 return error_mark_node;
6192 /* Check that we have the right number of arguments. */
6194 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6195 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6198 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6199 error ("wrong number of template arguments (%d, should be %d)",
6200 nargs, needed_parms);
6201 return error_mark_node;
6204 /* If we aren't able to check the actual arguments now
6205 (because they haven't been expanded yet), we can at least
6206 verify that all of the types used for the non-type
6207 template parameter pack are, in fact, valid for non-type
6208 template parameters. */
6210 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6212 int j, len = TREE_VEC_LENGTH (packed_types);
6213 for (j = 0; j < len; ++j)
6215 tree t = TREE_VEC_ELT (packed_types, j);
6216 if (invalid_nontype_parm_type_p (t, complain))
6217 return error_mark_node;
6222 /* Convert the remaining arguments, which will be a part of the
6223 parameter pack "parm". */
6224 for (; arg_idx < nargs; ++arg_idx)
6226 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6227 tree actual_parm = TREE_VALUE (parm);
6229 if (packed_types && !PACK_EXPANSION_P (arg))
6231 /* When we have a vector of types (corresponding to the
6232 non-type template parameter pack that uses parameter
6233 packs in its type, as mention above), and the
6234 argument is not an expansion (which expands to a
6235 currently unknown number of arguments), clone the
6236 parm and give it the next type in PACKED_TYPES. */
6237 actual_parm = copy_node (actual_parm);
6238 TREE_TYPE (actual_parm) =
6239 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6242 if (arg != error_mark_node)
6243 arg = convert_template_argument (actual_parm,
6244 arg, new_args, complain, parm_idx,
6246 if (arg == error_mark_node)
6248 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6251 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6252 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6253 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6256 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6257 TREE_TYPE (argument_pack)
6258 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6259 TREE_CONSTANT (argument_pack) = 1;
6262 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6263 #ifdef ENABLE_CHECKING
6264 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6265 TREE_VEC_LENGTH (packed_args));
6267 return argument_pack;
6270 /* Convert all template arguments to their appropriate types, and
6271 return a vector containing the innermost resulting template
6272 arguments. If any error occurs, return error_mark_node. Error and
6273 warning messages are issued under control of COMPLAIN.
6275 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6276 for arguments not specified in ARGS. Otherwise, if
6277 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6278 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6279 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6283 coerce_template_parms (tree parms,
6286 tsubst_flags_t complain,
6287 bool require_all_args,
6288 bool use_default_args)
6290 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6293 tree new_inner_args;
6294 int saved_unevaluated_operand;
6295 int saved_inhibit_evaluation_warnings;
6297 /* When used as a boolean value, indicates whether this is a
6298 variadic template parameter list. Since it's an int, we can also
6299 subtract it from nparms to get the number of non-variadic
6303 if (args == error_mark_node)
6304 return error_mark_node;
6306 nparms = TREE_VEC_LENGTH (parms);
6308 /* Determine if there are any parameter packs. */
6309 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6311 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6312 if (template_parameter_pack_p (tparm))
6316 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6317 /* If there are 0 or 1 parameter packs, we need to expand any argument
6318 packs so that we can deduce a parameter pack from some non-packed args
6319 followed by an argument pack, as in variadic85.C. If there are more
6320 than that, we need to leave argument packs intact so the arguments are
6321 assigned to the right parameter packs. This should only happen when
6322 dealing with a nested class inside a partial specialization of a class
6323 template, as in variadic92.C. */
6324 if (variadic_p <= 1)
6325 inner_args = expand_template_argument_pack (inner_args);
6327 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6328 if ((nargs > nparms && !variadic_p)
6329 || (nargs < nparms - variadic_p
6331 && (!use_default_args
6332 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6333 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6335 if (complain & tf_error)
6340 error ("wrong number of template arguments "
6341 "(%d, should be %d or more)", nargs, nparms);
6344 error ("wrong number of template arguments "
6345 "(%d, should be %d)", nargs, nparms);
6348 error ("provided for %q+D", in_decl);
6351 return error_mark_node;
6354 /* We need to evaluate the template arguments, even though this
6355 template-id may be nested within a "sizeof". */
6356 saved_unevaluated_operand = cp_unevaluated_operand;
6357 cp_unevaluated_operand = 0;
6358 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6359 c_inhibit_evaluation_warnings = 0;
6360 new_inner_args = make_tree_vec (nparms);
6361 new_args = add_outermost_template_args (args, new_inner_args);
6362 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6367 /* Get the Ith template parameter. */
6368 parm = TREE_VEC_ELT (parms, parm_idx);
6370 if (parm == error_mark_node)
6372 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6376 /* Calculate the next argument. */
6377 if (arg_idx < nargs)
6378 arg = TREE_VEC_ELT (inner_args, arg_idx);
6382 if (template_parameter_pack_p (TREE_VALUE (parm))
6383 && !(arg && ARGUMENT_PACK_P (arg)))
6385 /* All remaining arguments will be placed in the
6386 template parameter pack PARM. */
6387 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6388 inner_args, arg_idx,
6392 /* Store this argument. */
6393 if (arg == error_mark_node)
6395 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6397 /* We are done with all of the arguments. */
6404 if (PACK_EXPANSION_P (arg))
6406 if (complain & tf_error)
6408 /* FIXME this restriction was removed by N2555; see
6410 /* If ARG is a pack expansion, but PARM is not a
6411 template parameter pack (if it were, we would have
6412 handled it above), we're trying to expand into a
6413 fixed-length argument list. */
6414 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6415 sorry ("cannot expand %<%E%> into a fixed-length "
6416 "argument list", arg);
6418 sorry ("cannot expand %<%T%> into a fixed-length "
6419 "argument list", arg);
6424 else if (require_all_args)
6426 /* There must be a default arg in this case. */
6427 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6429 /* The position of the first default template argument,
6430 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6432 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6433 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6438 if (arg == error_mark_node)
6440 if (complain & tf_error)
6441 error ("template argument %d is invalid", arg_idx + 1);
6444 /* This only occurs if there was an error in the template
6445 parameter list itself (which we would already have
6446 reported) that we are trying to recover from, e.g., a class
6447 template with a parameter list such as
6448 template<typename..., typename>. */
6451 arg = convert_template_argument (TREE_VALUE (parm),
6452 arg, new_args, complain,
6455 if (arg == error_mark_node)
6457 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6459 cp_unevaluated_operand = saved_unevaluated_operand;
6460 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6463 return error_mark_node;
6465 #ifdef ENABLE_CHECKING
6466 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6467 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6468 TREE_VEC_LENGTH (new_inner_args));
6471 return new_inner_args;
6474 /* Returns 1 if template args OT and NT are equivalent. */
6477 template_args_equal (tree ot, tree nt)
6481 if (nt == NULL_TREE || ot == NULL_TREE)
6484 if (TREE_CODE (nt) == TREE_VEC)
6485 /* For member templates */
6486 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6487 else if (PACK_EXPANSION_P (ot))
6488 return PACK_EXPANSION_P (nt)
6489 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6490 PACK_EXPANSION_PATTERN (nt));
6491 else if (ARGUMENT_PACK_P (ot))
6496 if (!ARGUMENT_PACK_P (nt))
6499 opack = ARGUMENT_PACK_ARGS (ot);
6500 npack = ARGUMENT_PACK_ARGS (nt);
6501 len = TREE_VEC_LENGTH (opack);
6502 if (TREE_VEC_LENGTH (npack) != len)
6504 for (i = 0; i < len; ++i)
6505 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6506 TREE_VEC_ELT (npack, i)))
6510 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6512 /* We get here probably because we are in the middle of substituting
6513 into the pattern of a pack expansion. In that case the
6514 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6515 interested in. So we want to use the initial pack argument for
6517 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6518 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6519 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6520 return template_args_equal (ot, nt);
6522 else if (TYPE_P (nt))
6523 return TYPE_P (ot) && same_type_p (ot, nt);
6524 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6527 return cp_tree_equal (ot, nt);
6530 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6531 of template arguments. Returns 0 otherwise. */
6534 comp_template_args (tree oldargs, tree newargs)
6538 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6541 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6543 tree nt = TREE_VEC_ELT (newargs, i);
6544 tree ot = TREE_VEC_ELT (oldargs, i);
6546 if (! template_args_equal (ot, nt))
6553 add_pending_template (tree d)
6555 tree ti = (TYPE_P (d)
6556 ? CLASSTYPE_TEMPLATE_INFO (d)
6557 : DECL_TEMPLATE_INFO (d));
6558 struct pending_template *pt;
6561 if (TI_PENDING_TEMPLATE_FLAG (ti))
6564 /* We are called both from instantiate_decl, where we've already had a
6565 tinst_level pushed, and instantiate_template, where we haven't.
6567 level = !current_tinst_level || current_tinst_level->decl != d;
6570 push_tinst_level (d);
6572 pt = ggc_alloc_pending_template ();
6574 pt->tinst = current_tinst_level;
6575 if (last_pending_template)
6576 last_pending_template->next = pt;
6578 pending_templates = pt;
6580 last_pending_template = pt;
6582 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6589 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6590 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6591 documentation for TEMPLATE_ID_EXPR. */
6594 lookup_template_function (tree fns, tree arglist)
6598 if (fns == error_mark_node || arglist == error_mark_node)
6599 return error_mark_node;
6601 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6602 gcc_assert (fns && (is_overloaded_fn (fns)
6603 || TREE_CODE (fns) == IDENTIFIER_NODE));
6605 if (BASELINK_P (fns))
6607 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6609 BASELINK_FUNCTIONS (fns),
6614 type = TREE_TYPE (fns);
6615 if (TREE_CODE (fns) == OVERLOAD || !type)
6616 type = unknown_type_node;
6618 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6621 /* Within the scope of a template class S<T>, the name S gets bound
6622 (in build_self_reference) to a TYPE_DECL for the class, not a
6623 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6624 or one of its enclosing classes, and that type is a template,
6625 return the associated TEMPLATE_DECL. Otherwise, the original
6628 Also handle the case when DECL is a TREE_LIST of ambiguous
6629 injected-class-names from different bases. */
6632 maybe_get_template_decl_from_type_decl (tree decl)
6634 if (decl == NULL_TREE)
6637 /* DR 176: A lookup that finds an injected-class-name (10.2
6638 [class.member.lookup]) can result in an ambiguity in certain cases
6639 (for example, if it is found in more than one base class). If all of
6640 the injected-class-names that are found refer to specializations of
6641 the same class template, and if the name is followed by a
6642 template-argument-list, the reference refers to the class template
6643 itself and not a specialization thereof, and is not ambiguous. */
6644 if (TREE_CODE (decl) == TREE_LIST)
6646 tree t, tmpl = NULL_TREE;
6647 for (t = decl; t; t = TREE_CHAIN (t))
6649 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6652 else if (tmpl != elt)
6655 if (tmpl && t == NULL_TREE)
6661 return (decl != NULL_TREE
6662 && DECL_SELF_REFERENCE_P (decl)
6663 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6664 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6667 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6668 parameters, find the desired type.
6670 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6672 IN_DECL, if non-NULL, is the template declaration we are trying to
6675 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6676 the class we are looking up.
6678 Issue error and warning messages under control of COMPLAIN.
6680 If the template class is really a local class in a template
6681 function, then the FUNCTION_CONTEXT is the function in which it is
6684 ??? Note that this function is currently called *twice* for each
6685 template-id: the first time from the parser, while creating the
6686 incomplete type (finish_template_type), and the second type during the
6687 real instantiation (instantiate_template_class). This is surely something
6688 that we want to avoid. It also causes some problems with argument
6689 coercion (see convert_nontype_argument for more information on this). */
6692 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
6693 int entering_scope, tsubst_flags_t complain)
6695 tree templ = NULL_TREE, parmlist;
6702 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6704 tree value = innermost_non_namespace_value (d1);
6705 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6710 push_decl_namespace (context);
6711 templ = lookup_name (d1);
6712 templ = maybe_get_template_decl_from_type_decl (templ);
6714 pop_decl_namespace ();
6717 context = DECL_CONTEXT (templ);
6719 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6721 tree type = TREE_TYPE (d1);
6723 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6724 an implicit typename for the second A. Deal with it. */
6725 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6726 type = TREE_TYPE (type);
6728 if (CLASSTYPE_TEMPLATE_INFO (type))
6730 templ = CLASSTYPE_TI_TEMPLATE (type);
6731 d1 = DECL_NAME (templ);
6734 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6735 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6737 templ = TYPE_TI_TEMPLATE (d1);
6738 d1 = DECL_NAME (templ);
6740 else if (TREE_CODE (d1) == TEMPLATE_DECL
6741 && DECL_TEMPLATE_RESULT (d1)
6742 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6745 d1 = DECL_NAME (templ);
6746 context = DECL_CONTEXT (templ);
6749 /* Issue an error message if we didn't find a template. */
6752 if (complain & tf_error)
6753 error ("%qT is not a template", d1);
6754 return error_mark_node;
6757 if (TREE_CODE (templ) != TEMPLATE_DECL
6758 /* Make sure it's a user visible template, if it was named by
6760 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6761 && !PRIMARY_TEMPLATE_P (templ)))
6763 if (complain & tf_error)
6765 error ("non-template type %qT used as a template", d1);
6767 error ("for template declaration %q+D", in_decl);
6769 return error_mark_node;
6772 complain &= ~tf_user;
6774 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6776 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6777 template arguments */
6783 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6785 /* Consider an example where a template template parameter declared as
6787 template <class T, class U = std::allocator<T> > class TT
6789 The template parameter level of T and U are one level larger than
6790 of TT. To proper process the default argument of U, say when an
6791 instantiation `TT<int>' is seen, we need to build the full
6792 arguments containing {int} as the innermost level. Outer levels,
6793 available when not appearing as default template argument, can be
6794 obtained from the arguments of the enclosing template.
6796 Suppose that TT is later substituted with std::vector. The above
6797 instantiation is `TT<int, std::allocator<T> >' with TT at
6798 level 1, and T at level 2, while the template arguments at level 1
6799 becomes {std::vector} and the inner level 2 is {int}. */
6801 outer = DECL_CONTEXT (templ);
6803 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6804 else if (current_template_parms)
6805 /* This is an argument of the current template, so we haven't set
6806 DECL_CONTEXT yet. */
6807 outer = current_template_args ();
6810 arglist = add_to_template_args (outer, arglist);
6812 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6814 /*require_all_args=*/true,
6815 /*use_default_args=*/true);
6816 if (arglist2 == error_mark_node
6817 || (!uses_template_parms (arglist2)
6818 && check_instantiated_args (templ, arglist2, complain)))
6819 return error_mark_node;
6821 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6826 tree template_type = TREE_TYPE (templ);
6829 tree found = NULL_TREE;
6832 int is_dependent_type;
6833 int use_partial_inst_tmpl = false;
6835 gen_tmpl = most_general_template (templ);
6836 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6837 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6838 arg_depth = TMPL_ARGS_DEPTH (arglist);
6840 if (arg_depth == 1 && parm_depth > 1)
6842 /* We've been given an incomplete set of template arguments.
6845 template <class T> struct S1 {
6846 template <class U> struct S2 {};
6847 template <class U> struct S2<U*> {};
6850 we will be called with an ARGLIST of `U*', but the
6851 TEMPLATE will be `template <class T> template
6852 <class U> struct S1<T>::S2'. We must fill in the missing
6855 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6857 arg_depth = TMPL_ARGS_DEPTH (arglist);
6860 /* Now we should have enough arguments. */
6861 gcc_assert (parm_depth == arg_depth);
6863 /* From here on, we're only interested in the most general
6866 /* Calculate the BOUND_ARGS. These will be the args that are
6867 actually tsubst'd into the definition to create the
6871 /* We have multiple levels of arguments to coerce, at once. */
6873 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6875 tree bound_args = make_tree_vec (parm_depth);
6877 for (i = saved_depth,
6878 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6879 i > 0 && t != NULL_TREE;
6880 --i, t = TREE_CHAIN (t))
6883 if (i == saved_depth)
6884 a = coerce_template_parms (TREE_VALUE (t),
6887 /*require_all_args=*/true,
6888 /*use_default_args=*/true);
6890 /* Outer levels should have already been coerced. */
6891 a = TMPL_ARGS_LEVEL (arglist, i);
6893 /* Don't process further if one of the levels fails. */
6894 if (a == error_mark_node)
6896 /* Restore the ARGLIST to its full size. */
6897 TREE_VEC_LENGTH (arglist) = saved_depth;
6898 return error_mark_node;
6901 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6903 /* We temporarily reduce the length of the ARGLIST so
6904 that coerce_template_parms will see only the arguments
6905 corresponding to the template parameters it is
6907 TREE_VEC_LENGTH (arglist)--;
6910 /* Restore the ARGLIST to its full size. */
6911 TREE_VEC_LENGTH (arglist) = saved_depth;
6913 arglist = bound_args;
6917 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6918 INNERMOST_TEMPLATE_ARGS (arglist),
6921 /*require_all_args=*/true,
6922 /*use_default_args=*/true);
6924 if (arglist == error_mark_node)
6925 /* We were unable to bind the arguments. */
6926 return error_mark_node;
6928 /* In the scope of a template class, explicit references to the
6929 template class refer to the type of the template, not any
6930 instantiation of it. For example, in:
6932 template <class T> class C { void f(C<T>); }
6934 the `C<T>' is just the same as `C'. Outside of the
6935 class, however, such a reference is an instantiation. */
6937 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6938 || currently_open_class (template_type))
6939 /* comp_template_args is expensive, check it last. */
6940 && comp_template_args (TYPE_TI_ARGS (template_type),
6942 return template_type;
6944 /* If we already have this specialization, return it. */
6945 elt.tmpl = gen_tmpl;
6947 hash = hash_specialization (&elt);
6948 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6954 is_dependent_type = uses_template_parms (arglist);
6956 /* If the deduced arguments are invalid, then the binding
6958 if (!is_dependent_type
6959 && check_instantiated_args (gen_tmpl,
6960 INNERMOST_TEMPLATE_ARGS (arglist),
6962 return error_mark_node;
6964 if (!is_dependent_type
6965 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6966 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6967 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6969 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6970 DECL_NAME (gen_tmpl),
6971 /*tag_scope=*/ts_global);
6975 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6978 context = global_namespace;
6980 /* Create the type. */
6981 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6983 if (!is_dependent_type)
6985 set_current_access_from_decl (TYPE_NAME (template_type));
6986 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
6987 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6988 arglist, complain, in_decl),
6989 SCOPED_ENUM_P (template_type), NULL);
6993 /* We don't want to call start_enum for this type, since
6994 the values for the enumeration constants may involve
6995 template parameters. And, no one should be interested
6996 in the enumeration constants for such a type. */
6997 t = cxx_make_type (ENUMERAL_TYPE);
6998 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7000 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7001 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7002 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7006 t = make_class_type (TREE_CODE (template_type));
7007 CLASSTYPE_DECLARED_CLASS (t)
7008 = CLASSTYPE_DECLARED_CLASS (template_type);
7009 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7010 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7012 /* A local class. Make sure the decl gets registered properly. */
7013 if (context == current_function_decl)
7014 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7016 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7017 /* This instantiation is another name for the primary
7018 template type. Set the TYPE_CANONICAL field
7020 TYPE_CANONICAL (t) = template_type;
7021 else if (any_template_arguments_need_structural_equality_p (arglist))
7022 /* Some of the template arguments require structural
7023 equality testing, so this template class requires
7024 structural equality testing. */
7025 SET_TYPE_STRUCTURAL_EQUALITY (t);
7028 /* If we called start_enum or pushtag above, this information
7029 will already be set up. */
7032 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7034 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7035 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7036 DECL_SOURCE_LOCATION (type_decl)
7037 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7040 type_decl = TYPE_NAME (t);
7042 TREE_PRIVATE (type_decl)
7043 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7044 TREE_PROTECTED (type_decl)
7045 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7046 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7048 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7049 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7052 /* Let's consider the explicit specialization of a member
7053 of a class template specialization that is implicitely instantiated,
7058 template<class U> struct M {}; //#0
7063 struct S<int>::M<char> //#1
7067 [temp.expl.spec]/4 says this is valid.
7069 In this case, when we write:
7072 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7075 When we encounter #1, we want to store the partial instantiation
7076 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7078 For all cases other than this "explicit specialization of member of a
7079 class template", we just want to store the most general template into
7080 the CLASSTYPE_TI_TEMPLATE of M.
7082 This case of "explicit specialization of member of a class template"
7084 1/ the enclosing class is an instantiation of, and therefore not
7085 the same as, the context of the most general template, and
7086 2/ we aren't looking at the partial instantiation itself, i.e.
7087 the innermost arguments are not the same as the innermost parms of
7088 the most general template.
7090 So it's only when 1/ and 2/ happens that we want to use the partial
7091 instantiation of the member template in lieu of its most general
7094 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7095 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7096 /* the enclosing class must be an instantiation... */
7097 && CLASS_TYPE_P (context)
7098 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7100 tree partial_inst_args;
7101 TREE_VEC_LENGTH (arglist)--;
7102 ++processing_template_decl;
7104 tsubst (INNERMOST_TEMPLATE_ARGS
7105 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7106 arglist, complain, NULL_TREE);
7107 --processing_template_decl;
7108 TREE_VEC_LENGTH (arglist)++;
7109 use_partial_inst_tmpl =
7110 /*...and we must not be looking at the partial instantiation
7112 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7116 if (!use_partial_inst_tmpl)
7117 /* This case is easy; there are no member templates involved. */
7121 /* This is a full instantiation of a member template. Find
7122 the partial instantiation of which this is an instance. */
7124 /* Temporarily reduce by one the number of levels in the ARGLIST
7125 so as to avoid comparing the last set of arguments. */
7126 TREE_VEC_LENGTH (arglist)--;
7127 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7128 TREE_VEC_LENGTH (arglist)++;
7129 found = CLASSTYPE_TI_TEMPLATE (found);
7132 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7135 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
7136 &elt, hash, INSERT);
7137 *slot = ggc_alloc_spec_entry ();
7140 /* Note this use of the partial instantiation so we can check it
7141 later in maybe_process_partial_specialization. */
7142 DECL_TEMPLATE_INSTANTIATIONS (templ)
7143 = tree_cons (arglist, t,
7144 DECL_TEMPLATE_INSTANTIATIONS (templ));
7146 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7147 /* Now that the type has been registered on the instantiations
7148 list, we set up the enumerators. Because the enumeration
7149 constants may involve the enumeration type itself, we make
7150 sure to register the type first, and then create the
7151 constants. That way, doing tsubst_expr for the enumeration
7152 constants won't result in recursive calls here; we'll find
7153 the instantiation and exit above. */
7154 tsubst_enum (template_type, t, arglist);
7156 if (is_dependent_type)
7157 /* If the type makes use of template parameters, the
7158 code that generates debugging information will crash. */
7159 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7161 /* Possibly limit visibility based on template args. */
7162 TREE_PUBLIC (type_decl) = 1;
7163 determine_visibility (type_decl);
7169 /* Wrapper for lookup_template_class_1. */
7172 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7173 int entering_scope, tsubst_flags_t complain)
7176 timevar_push (TV_TEMPLATE_INST);
7177 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7178 entering_scope, complain);
7179 timevar_pop (TV_TEMPLATE_INST);
7187 /* True when we should also visit template parameters that occur in
7188 non-deduced contexts. */
7189 bool include_nondeduced_p;
7190 struct pointer_set_t *visited;
7193 /* Called from for_each_template_parm via walk_tree. */
7196 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7199 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7200 tree_fn_t fn = pfd->fn;
7201 void *data = pfd->data;
7204 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7205 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7206 pfd->include_nondeduced_p))
7207 return error_mark_node;
7209 switch (TREE_CODE (t))
7212 if (TYPE_PTRMEMFUNC_P (t))
7218 if (!TYPE_TEMPLATE_INFO (t))
7220 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7221 fn, data, pfd->visited,
7222 pfd->include_nondeduced_p))
7223 return error_mark_node;
7227 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7228 fn, data, pfd->visited,
7229 pfd->include_nondeduced_p)
7230 || for_each_template_parm (TYPE_MAX_VALUE (t),
7231 fn, data, pfd->visited,
7232 pfd->include_nondeduced_p))
7233 return error_mark_node;
7237 /* Since we're not going to walk subtrees, we have to do this
7239 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7240 pfd->visited, pfd->include_nondeduced_p))
7241 return error_mark_node;
7245 /* Check the return type. */
7246 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7247 pfd->include_nondeduced_p))
7248 return error_mark_node;
7250 /* Check the parameter types. Since default arguments are not
7251 instantiated until they are needed, the TYPE_ARG_TYPES may
7252 contain expressions that involve template parameters. But,
7253 no-one should be looking at them yet. And, once they're
7254 instantiated, they don't contain template parameters, so
7255 there's no point in looking at them then, either. */
7259 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7260 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7261 pfd->visited, pfd->include_nondeduced_p))
7262 return error_mark_node;
7264 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7265 want walk_tree walking into them itself. */
7271 case UNDERLYING_TYPE:
7272 if (pfd->include_nondeduced_p
7273 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7275 pfd->include_nondeduced_p))
7276 return error_mark_node;
7281 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7282 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7283 pfd->visited, pfd->include_nondeduced_p))
7284 return error_mark_node;
7289 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7290 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7291 pfd->visited, pfd->include_nondeduced_p))
7292 return error_mark_node;
7293 if (DECL_CONTEXT (t)
7294 && pfd->include_nondeduced_p
7295 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7296 pfd->visited, pfd->include_nondeduced_p))
7297 return error_mark_node;
7300 case BOUND_TEMPLATE_TEMPLATE_PARM:
7301 /* Record template parameters such as `T' inside `TT<T>'. */
7302 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7303 pfd->include_nondeduced_p))
7304 return error_mark_node;
7307 case TEMPLATE_TEMPLATE_PARM:
7308 case TEMPLATE_TYPE_PARM:
7309 case TEMPLATE_PARM_INDEX:
7310 if (fn && (*fn)(t, data))
7311 return error_mark_node;
7313 return error_mark_node;
7317 /* A template template parameter is encountered. */
7318 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7319 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7320 pfd->include_nondeduced_p))
7321 return error_mark_node;
7323 /* Already substituted template template parameter */
7329 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7331 pfd->include_nondeduced_p))
7332 return error_mark_node;
7336 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7337 && pfd->include_nondeduced_p
7338 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7339 (TREE_TYPE (t)), fn, data,
7340 pfd->visited, pfd->include_nondeduced_p))
7341 return error_mark_node;
7346 /* If there's no type, then this thing must be some expression
7347 involving template parameters. */
7348 if (!fn && !TREE_TYPE (t))
7349 return error_mark_node;
7354 case REINTERPRET_CAST_EXPR:
7355 case CONST_CAST_EXPR:
7356 case STATIC_CAST_EXPR:
7357 case DYNAMIC_CAST_EXPR:
7361 case PSEUDO_DTOR_EXPR:
7363 return error_mark_node;
7370 /* We didn't find any template parameters we liked. */
7374 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7375 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7376 call FN with the parameter and the DATA.
7377 If FN returns nonzero, the iteration is terminated, and
7378 for_each_template_parm returns 1. Otherwise, the iteration
7379 continues. If FN never returns a nonzero value, the value
7380 returned by for_each_template_parm is 0. If FN is NULL, it is
7381 considered to be the function which always returns 1.
7383 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7384 parameters that occur in non-deduced contexts. When false, only
7385 visits those template parameters that can be deduced. */
7388 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7389 struct pointer_set_t *visited,
7390 bool include_nondeduced_p)
7392 struct pair_fn_data pfd;
7398 pfd.include_nondeduced_p = include_nondeduced_p;
7400 /* Walk the tree. (Conceptually, we would like to walk without
7401 duplicates, but for_each_template_parm_r recursively calls
7402 for_each_template_parm, so we would need to reorganize a fair
7403 bit to use walk_tree_without_duplicates, so we keep our own
7406 pfd.visited = visited;
7408 pfd.visited = pointer_set_create ();
7409 result = cp_walk_tree (&t,
7410 for_each_template_parm_r,
7412 pfd.visited) != NULL_TREE;
7417 pointer_set_destroy (pfd.visited);
7424 /* Returns true if T depends on any template parameter. */
7427 uses_template_parms (tree t)
7430 int saved_processing_template_decl;
7432 saved_processing_template_decl = processing_template_decl;
7433 if (!saved_processing_template_decl)
7434 processing_template_decl = 1;
7436 dependent_p = dependent_type_p (t);
7437 else if (TREE_CODE (t) == TREE_VEC)
7438 dependent_p = any_dependent_template_arguments_p (t);
7439 else if (TREE_CODE (t) == TREE_LIST)
7440 dependent_p = (uses_template_parms (TREE_VALUE (t))
7441 || uses_template_parms (TREE_CHAIN (t)));
7442 else if (TREE_CODE (t) == TYPE_DECL)
7443 dependent_p = dependent_type_p (TREE_TYPE (t));
7446 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7447 || TREE_CODE (t) == OVERLOAD
7448 || TREE_CODE (t) == BASELINK
7449 || TREE_CODE (t) == IDENTIFIER_NODE
7450 || TREE_CODE (t) == TRAIT_EXPR
7451 || TREE_CODE (t) == CONSTRUCTOR
7452 || CONSTANT_CLASS_P (t))
7453 dependent_p = (type_dependent_expression_p (t)
7454 || value_dependent_expression_p (t));
7457 gcc_assert (t == error_mark_node);
7458 dependent_p = false;
7461 processing_template_decl = saved_processing_template_decl;
7466 /* Returns true if T depends on any template parameter with level LEVEL. */
7469 uses_template_parms_level (tree t, int level)
7471 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7472 /*include_nondeduced_p=*/true);
7475 static int tinst_depth;
7476 extern int max_tinst_depth;
7477 #ifdef GATHER_STATISTICS
7480 static int tinst_level_tick;
7481 static int last_template_error_tick;
7483 /* We're starting to instantiate D; record the template instantiation context
7484 for diagnostics and to restore it later. */
7487 push_tinst_level (tree d)
7489 struct tinst_level *new_level;
7491 if (tinst_depth >= max_tinst_depth)
7493 last_template_error_tick = tinst_level_tick;
7494 if (TREE_CODE (d) == TREE_LIST)
7495 error ("template instantiation depth exceeds maximum of %d (use "
7496 "-ftemplate-depth= to increase the maximum) substituting %qS",
7497 max_tinst_depth, d);
7499 error ("template instantiation depth exceeds maximum of %d (use "
7500 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7501 max_tinst_depth, d);
7503 print_instantiation_context ();
7508 new_level = ggc_alloc_tinst_level ();
7509 new_level->decl = d;
7510 new_level->locus = input_location;
7511 new_level->in_system_header_p = in_system_header;
7512 new_level->next = current_tinst_level;
7513 current_tinst_level = new_level;
7516 #ifdef GATHER_STATISTICS
7517 if (tinst_depth > depth_reached)
7518 depth_reached = tinst_depth;
7525 /* We're done instantiating this template; return to the instantiation
7529 pop_tinst_level (void)
7531 /* Restore the filename and line number stashed away when we started
7532 this instantiation. */
7533 input_location = current_tinst_level->locus;
7534 current_tinst_level = current_tinst_level->next;
7539 /* We're instantiating a deferred template; restore the template
7540 instantiation context in which the instantiation was requested, which
7541 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7544 reopen_tinst_level (struct tinst_level *level)
7546 struct tinst_level *t;
7549 for (t = level; t; t = t->next)
7552 current_tinst_level = level;
7557 /* Returns the TINST_LEVEL which gives the original instantiation
7560 struct tinst_level *
7561 outermost_tinst_level (void)
7563 struct tinst_level *level = current_tinst_level;
7566 level = level->next;
7570 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7573 parameter_of_template_p (tree parm, tree templ)
7578 if (!parm || !templ)
7581 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7582 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7584 parms = DECL_TEMPLATE_PARMS (templ);
7585 parms = INNERMOST_TEMPLATE_PARMS (parms);
7587 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7588 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7594 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7595 vector of template arguments, as for tsubst.
7597 Returns an appropriate tsubst'd friend declaration. */
7600 tsubst_friend_function (tree decl, tree args)
7604 if (TREE_CODE (decl) == FUNCTION_DECL
7605 && DECL_TEMPLATE_INSTANTIATION (decl)
7606 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7607 /* This was a friend declared with an explicit template
7608 argument list, e.g.:
7612 to indicate that f was a template instantiation, not a new
7613 function declaration. Now, we have to figure out what
7614 instantiation of what template. */
7616 tree template_id, arglist, fns;
7619 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7621 /* Friend functions are looked up in the containing namespace scope.
7622 We must enter that scope, to avoid finding member functions of the
7623 current class with same name. */
7624 push_nested_namespace (ns);
7625 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7626 tf_warning_or_error, NULL_TREE,
7627 /*integral_constant_expression_p=*/false);
7628 pop_nested_namespace (ns);
7629 arglist = tsubst (DECL_TI_ARGS (decl), args,
7630 tf_warning_or_error, NULL_TREE);
7631 template_id = lookup_template_function (fns, arglist);
7633 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7634 tmpl = determine_specialization (template_id, new_friend,
7636 /*need_member_template=*/0,
7637 TREE_VEC_LENGTH (args),
7639 return instantiate_template (tmpl, new_args, tf_error);
7642 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7644 /* The NEW_FRIEND will look like an instantiation, to the
7645 compiler, but is not an instantiation from the point of view of
7646 the language. For example, we might have had:
7648 template <class T> struct S {
7649 template <class U> friend void f(T, U);
7652 Then, in S<int>, template <class U> void f(int, U) is not an
7653 instantiation of anything. */
7654 if (new_friend == error_mark_node)
7655 return error_mark_node;
7657 DECL_USE_TEMPLATE (new_friend) = 0;
7658 if (TREE_CODE (decl) == TEMPLATE_DECL)
7660 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7661 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7662 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7665 /* The mangled name for the NEW_FRIEND is incorrect. The function
7666 is not a template instantiation and should not be mangled like
7667 one. Therefore, we forget the mangling here; we'll recompute it
7668 later if we need it. */
7669 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7671 SET_DECL_RTL (new_friend, NULL);
7672 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7675 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7678 tree new_friend_template_info;
7679 tree new_friend_result_template_info;
7681 int new_friend_is_defn;
7683 /* We must save some information from NEW_FRIEND before calling
7684 duplicate decls since that function will free NEW_FRIEND if
7686 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7687 new_friend_is_defn =
7688 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7689 (template_for_substitution (new_friend)))
7691 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7693 /* This declaration is a `primary' template. */
7694 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7696 new_friend_result_template_info
7697 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7700 new_friend_result_template_info = NULL_TREE;
7702 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7703 if (new_friend_is_defn)
7704 DECL_INITIAL (new_friend) = error_mark_node;
7706 /* Inside pushdecl_namespace_level, we will push into the
7707 current namespace. However, the friend function should go
7708 into the namespace of the template. */
7709 ns = decl_namespace_context (new_friend);
7710 push_nested_namespace (ns);
7711 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7712 pop_nested_namespace (ns);
7714 if (old_decl == error_mark_node)
7715 return error_mark_node;
7717 if (old_decl != new_friend)
7719 /* This new friend declaration matched an existing
7720 declaration. For example, given:
7722 template <class T> void f(T);
7723 template <class U> class C {
7724 template <class T> friend void f(T) {}
7727 the friend declaration actually provides the definition
7728 of `f', once C has been instantiated for some type. So,
7729 old_decl will be the out-of-class template declaration,
7730 while new_friend is the in-class definition.
7732 But, if `f' was called before this point, the
7733 instantiation of `f' will have DECL_TI_ARGS corresponding
7734 to `T' but not to `U', references to which might appear
7735 in the definition of `f'. Previously, the most general
7736 template for an instantiation of `f' was the out-of-class
7737 version; now it is the in-class version. Therefore, we
7738 run through all specialization of `f', adding to their
7739 DECL_TI_ARGS appropriately. In particular, they need a
7740 new set of outer arguments, corresponding to the
7741 arguments for this class instantiation.
7743 The same situation can arise with something like this:
7746 template <class T> class C {
7750 when `C<int>' is instantiated. Now, `f(int)' is defined
7753 if (!new_friend_is_defn)
7754 /* On the other hand, if the in-class declaration does
7755 *not* provide a definition, then we don't want to alter
7756 existing definitions. We can just leave everything
7761 tree new_template = TI_TEMPLATE (new_friend_template_info);
7762 tree new_args = TI_ARGS (new_friend_template_info);
7764 /* Overwrite whatever template info was there before, if
7765 any, with the new template information pertaining to
7767 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7769 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7771 /* We should have called reregister_specialization in
7773 gcc_assert (retrieve_specialization (new_template,
7777 /* Instantiate it if the global has already been used. */
7778 if (DECL_ODR_USED (old_decl))
7779 instantiate_decl (old_decl, /*defer_ok=*/true,
7780 /*expl_inst_class_mem_p=*/false);
7786 /* Indicate that the old function template is a partial
7788 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7789 = new_friend_result_template_info;
7791 gcc_assert (new_template
7792 == most_general_template (new_template));
7793 gcc_assert (new_template != old_decl);
7795 /* Reassign any specializations already in the hash table
7796 to the new more general template, and add the
7797 additional template args. */
7798 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7802 tree spec = TREE_VALUE (t);
7805 elt.tmpl = old_decl;
7806 elt.args = DECL_TI_ARGS (spec);
7807 elt.spec = NULL_TREE;
7809 htab_remove_elt (decl_specializations, &elt);
7812 = add_outermost_template_args (new_args,
7813 DECL_TI_ARGS (spec));
7815 register_specialization
7816 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7819 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7823 /* The information from NEW_FRIEND has been merged into OLD_DECL
7824 by duplicate_decls. */
7825 new_friend = old_decl;
7830 tree context = DECL_CONTEXT (new_friend);
7834 template <class T> class C {
7835 template <class U> friend void C1<U>::f (); // case 1
7836 friend void C2<T>::f (); // case 2
7838 we only need to make sure CONTEXT is a complete type for
7839 case 2. To distinguish between the two cases, we note that
7840 CONTEXT of case 1 remains dependent type after tsubst while
7841 this isn't true for case 2. */
7842 ++processing_template_decl;
7843 dependent_p = dependent_type_p (context);
7844 --processing_template_decl;
7847 && !complete_type_or_else (context, NULL_TREE))
7848 return error_mark_node;
7850 if (COMPLETE_TYPE_P (context))
7852 /* Check to see that the declaration is really present, and,
7853 possibly obtain an improved declaration. */
7854 tree fn = check_classfn (context,
7855 new_friend, NULL_TREE);
7865 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7866 template arguments, as for tsubst.
7868 Returns an appropriate tsubst'd friend type or error_mark_node on
7872 tsubst_friend_class (tree friend_tmpl, tree args)
7878 context = CP_DECL_CONTEXT (friend_tmpl);
7880 if (context != global_namespace)
7882 if (TREE_CODE (context) == NAMESPACE_DECL)
7883 push_nested_namespace (context);
7885 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7888 /* Look for a class template declaration. We look for hidden names
7889 because two friend declarations of the same template are the
7890 same. For example, in:
7893 template <typename> friend class F;
7895 template <typename> struct B {
7896 template <typename> friend class F;
7899 both F templates are the same. */
7900 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7901 /*block_p=*/true, 0,
7902 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7904 /* But, if we don't find one, it might be because we're in a
7905 situation like this:
7913 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7914 for `S<int>', not the TEMPLATE_DECL. */
7915 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7917 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7918 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7921 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7923 /* The friend template has already been declared. Just
7924 check to see that the declarations match, and install any new
7925 default parameters. We must tsubst the default parameters,
7926 of course. We only need the innermost template parameters
7927 because that is all that redeclare_class_template will look
7929 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7930 > TMPL_ARGS_DEPTH (args))
7933 location_t saved_input_location;
7934 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7935 args, tf_warning_or_error);
7937 saved_input_location = input_location;
7938 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7939 redeclare_class_template (TREE_TYPE (tmpl), parms);
7940 input_location = saved_input_location;
7944 friend_type = TREE_TYPE (tmpl);
7948 /* The friend template has not already been declared. In this
7949 case, the instantiation of the template class will cause the
7950 injection of this template into the global scope. */
7951 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7952 if (tmpl == error_mark_node)
7953 return error_mark_node;
7955 /* The new TMPL is not an instantiation of anything, so we
7956 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7957 the new type because that is supposed to be the corresponding
7958 template decl, i.e., TMPL. */
7959 DECL_USE_TEMPLATE (tmpl) = 0;
7960 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7961 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7962 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7963 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7965 /* Inject this template into the global scope. */
7966 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7969 if (context != global_namespace)
7971 if (TREE_CODE (context) == NAMESPACE_DECL)
7972 pop_nested_namespace (context);
7974 pop_nested_class ();
7980 /* Returns zero if TYPE cannot be completed later due to circularity.
7981 Otherwise returns one. */
7984 can_complete_type_without_circularity (tree type)
7986 if (type == NULL_TREE || type == error_mark_node)
7988 else if (COMPLETE_TYPE_P (type))
7990 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7991 return can_complete_type_without_circularity (TREE_TYPE (type));
7992 else if (CLASS_TYPE_P (type)
7993 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7999 /* Apply any attributes which had to be deferred until instantiation
8000 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8001 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8004 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8005 tree args, tsubst_flags_t complain, tree in_decl)
8007 tree last_dep = NULL_TREE;
8011 for (t = attributes; t; t = TREE_CHAIN (t))
8012 if (ATTR_IS_DEPENDENT (t))
8015 attributes = copy_list (attributes);
8019 if (DECL_P (*decl_p))
8021 if (TREE_TYPE (*decl_p) == error_mark_node)
8023 p = &DECL_ATTRIBUTES (*decl_p);
8026 p = &TYPE_ATTRIBUTES (*decl_p);
8030 tree late_attrs = NULL_TREE;
8031 tree *q = &late_attrs;
8033 for (*p = attributes; *p; )
8036 if (ATTR_IS_DEPENDENT (t))
8038 *p = TREE_CHAIN (t);
8039 TREE_CHAIN (t) = NULL_TREE;
8040 /* If the first attribute argument is an identifier, don't
8041 pass it through tsubst. Attributes like mode, format,
8042 cleanup and several target specific attributes expect it
8045 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8046 && TREE_VALUE (TREE_VALUE (t))
8047 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8048 == IDENTIFIER_NODE))
8051 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8053 /*integral_constant_expression_p=*/false);
8054 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8056 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8061 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8062 /*integral_constant_expression_p=*/false);
8064 q = &TREE_CHAIN (t);
8067 p = &TREE_CHAIN (t);
8070 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8074 /* Perform (or defer) access check for typedefs that were referenced
8075 from within the template TMPL code.
8076 This is a subroutine of instantiate_template and instantiate_class_template.
8077 TMPL is the template to consider and TARGS is the list of arguments of
8081 perform_typedefs_access_check (tree tmpl, tree targs)
8083 location_t saved_location;
8085 qualified_typedef_usage_t *iter;
8088 || (!CLASS_TYPE_P (tmpl)
8089 && TREE_CODE (tmpl) != FUNCTION_DECL))
8092 saved_location = input_location;
8093 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8094 get_types_needing_access_check (tmpl),
8097 tree type_decl = iter->typedef_decl;
8098 tree type_scope = iter->context;
8100 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8103 if (uses_template_parms (type_decl))
8104 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8105 if (uses_template_parms (type_scope))
8106 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8108 /* Make access check error messages point to the location
8109 of the use of the typedef. */
8110 input_location = iter->locus;
8111 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8112 type_decl, type_decl);
8114 input_location = saved_location;
8118 instantiate_class_template_1 (tree type)
8120 tree templ, args, pattern, t, member;
8124 unsigned int saved_maximum_field_alignment;
8126 if (type == error_mark_node)
8127 return error_mark_node;
8129 if (COMPLETE_OR_OPEN_TYPE_P (type)
8130 || uses_template_parms (type))
8133 /* Figure out which template is being instantiated. */
8134 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8135 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8137 /* Determine what specialization of the original template to
8139 t = most_specialized_class (type, templ, tf_warning_or_error);
8140 if (t == error_mark_node)
8142 TYPE_BEING_DEFINED (type) = 1;
8143 return error_mark_node;
8147 /* This TYPE is actually an instantiation of a partial
8148 specialization. We replace the innermost set of ARGS with
8149 the arguments appropriate for substitution. For example,
8152 template <class T> struct S {};
8153 template <class T> struct S<T*> {};
8155 and supposing that we are instantiating S<int*>, ARGS will
8156 presently be {int*} -- but we need {int}. */
8157 pattern = TREE_TYPE (t);
8158 args = TREE_PURPOSE (t);
8162 pattern = TREE_TYPE (templ);
8163 args = CLASSTYPE_TI_ARGS (type);
8166 /* If the template we're instantiating is incomplete, then clearly
8167 there's nothing we can do. */
8168 if (!COMPLETE_TYPE_P (pattern))
8171 /* If we've recursively instantiated too many templates, stop. */
8172 if (! push_tinst_level (type))
8175 /* Now we're really doing the instantiation. Mark the type as in
8176 the process of being defined. */
8177 TYPE_BEING_DEFINED (type) = 1;
8179 /* We may be in the middle of deferred access check. Disable
8181 push_deferring_access_checks (dk_no_deferred);
8183 push_to_top_level ();
8184 /* Use #pragma pack from the template context. */
8185 saved_maximum_field_alignment = maximum_field_alignment;
8186 maximum_field_alignment = TYPE_PRECISION (pattern);
8188 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8190 /* Set the input location to the most specialized template definition.
8191 This is needed if tsubsting causes an error. */
8192 typedecl = TYPE_MAIN_DECL (pattern);
8193 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8194 DECL_SOURCE_LOCATION (typedecl);
8196 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
8197 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
8198 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
8199 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
8200 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
8201 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
8202 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
8203 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
8204 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
8205 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
8206 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8207 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8208 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8209 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8210 if (ANON_AGGR_TYPE_P (pattern))
8211 SET_ANON_AGGR_TYPE_P (type);
8212 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8214 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8215 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8217 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8219 pbinfo = TYPE_BINFO (pattern);
8221 /* We should never instantiate a nested class before its enclosing
8222 class; we need to look up the nested class by name before we can
8223 instantiate it, and that lookup should instantiate the enclosing
8225 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8226 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8228 base_list = NULL_TREE;
8229 if (BINFO_N_BASE_BINFOS (pbinfo))
8235 /* We must enter the scope containing the type, as that is where
8236 the accessibility of types named in dependent bases are
8238 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8240 /* Substitute into each of the bases to determine the actual
8242 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8245 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8246 tree expanded_bases = NULL_TREE;
8249 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8252 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8253 args, tf_error, NULL_TREE);
8254 if (expanded_bases == error_mark_node)
8257 len = TREE_VEC_LENGTH (expanded_bases);
8260 for (idx = 0; idx < len; idx++)
8263 /* Extract the already-expanded base class. */
8264 base = TREE_VEC_ELT (expanded_bases, idx);
8266 /* Substitute to figure out the base class. */
8267 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8270 if (base == error_mark_node)
8273 base_list = tree_cons (access, base, base_list);
8274 if (BINFO_VIRTUAL_P (pbase_binfo))
8275 TREE_TYPE (base_list) = integer_type_node;
8279 /* The list is now in reverse order; correct that. */
8280 base_list = nreverse (base_list);
8283 pop_scope (pushed_scope);
8285 /* Now call xref_basetypes to set up all the base-class
8287 xref_basetypes (type, base_list);
8289 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8290 (int) ATTR_FLAG_TYPE_IN_PLACE,
8291 args, tf_error, NULL_TREE);
8292 fixup_attribute_variants (type);
8294 /* Now that our base classes are set up, enter the scope of the
8295 class, so that name lookups into base classes, etc. will work
8296 correctly. This is precisely analogous to what we do in
8297 begin_class_definition when defining an ordinary non-template
8298 class, except we also need to push the enclosing classes. */
8299 push_nested_class (type);
8301 /* Now members are processed in the order of declaration. */
8302 for (member = CLASSTYPE_DECL_LIST (pattern);
8303 member; member = TREE_CHAIN (member))
8305 tree t = TREE_VALUE (member);
8307 if (TREE_PURPOSE (member))
8311 /* Build new CLASSTYPE_NESTED_UTDS. */
8314 bool class_template_p;
8316 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8317 && TYPE_LANG_SPECIFIC (t)
8318 && CLASSTYPE_IS_TEMPLATE (t));
8319 /* If the member is a class template, then -- even after
8320 substitution -- there may be dependent types in the
8321 template argument list for the class. We increment
8322 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8323 that function will assume that no types are dependent
8324 when outside of a template. */
8325 if (class_template_p)
8326 ++processing_template_decl;
8327 newtag = tsubst (t, args, tf_error, NULL_TREE);
8328 if (class_template_p)
8329 --processing_template_decl;
8330 if (newtag == error_mark_node)
8333 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8335 tree name = TYPE_IDENTIFIER (t);
8337 if (class_template_p)
8338 /* Unfortunately, lookup_template_class sets
8339 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8340 instantiation (i.e., for the type of a member
8341 template class nested within a template class.)
8342 This behavior is required for
8343 maybe_process_partial_specialization to work
8344 correctly, but is not accurate in this case;
8345 the TAG is not an instantiation of anything.
8346 (The corresponding TEMPLATE_DECL is an
8347 instantiation, but the TYPE is not.) */
8348 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8350 /* Now, we call pushtag to put this NEWTAG into the scope of
8351 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8352 pushtag calling push_template_decl. We don't have to do
8353 this for enums because it will already have been done in
8356 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8357 pushtag (name, newtag, /*tag_scope=*/ts_current);
8360 else if (TREE_CODE (t) == FUNCTION_DECL
8361 || DECL_FUNCTION_TEMPLATE_P (t))
8363 /* Build new TYPE_METHODS. */
8366 if (TREE_CODE (t) == TEMPLATE_DECL)
8367 ++processing_template_decl;
8368 r = tsubst (t, args, tf_error, NULL_TREE);
8369 if (TREE_CODE (t) == TEMPLATE_DECL)
8370 --processing_template_decl;
8371 set_current_access_from_decl (r);
8372 finish_member_declaration (r);
8376 /* Build new TYPE_FIELDS. */
8377 if (TREE_CODE (t) == STATIC_ASSERT)
8380 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8381 tf_warning_or_error, NULL_TREE,
8382 /*integral_constant_expression_p=*/true);
8383 finish_static_assert (condition,
8384 STATIC_ASSERT_MESSAGE (t),
8385 STATIC_ASSERT_SOURCE_LOCATION (t),
8388 else if (TREE_CODE (t) != CONST_DECL)
8392 /* The file and line for this declaration, to
8393 assist in error message reporting. Since we
8394 called push_tinst_level above, we don't need to
8396 input_location = DECL_SOURCE_LOCATION (t);
8398 if (TREE_CODE (t) == TEMPLATE_DECL)
8399 ++processing_template_decl;
8400 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8401 if (TREE_CODE (t) == TEMPLATE_DECL)
8402 --processing_template_decl;
8403 if (TREE_CODE (r) == VAR_DECL)
8407 [t]he initialization (and any associated
8408 side-effects) of a static data member does
8409 not occur unless the static data member is
8410 itself used in a way that requires the
8411 definition of the static data member to
8414 Therefore, we do not substitute into the
8415 initialized for the static data member here. */
8416 finish_static_data_member_decl
8419 /*init_const_expr_p=*/false,
8420 /*asmspec_tree=*/NULL_TREE,
8423 else if (TREE_CODE (r) == FIELD_DECL)
8425 /* Determine whether R has a valid type and can be
8426 completed later. If R is invalid, then it is
8427 replaced by error_mark_node so that it will not be
8428 added to TYPE_FIELDS. */
8429 tree rtype = TREE_TYPE (r);
8430 if (can_complete_type_without_circularity (rtype))
8431 complete_type (rtype);
8433 if (!COMPLETE_TYPE_P (rtype))
8435 cxx_incomplete_type_error (r, rtype);
8436 r = error_mark_node;
8440 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8441 such a thing will already have been added to the field
8442 list by tsubst_enum in finish_member_declaration in the
8443 CLASSTYPE_NESTED_UTDS case above. */
8444 if (!(TREE_CODE (r) == TYPE_DECL
8445 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8446 && DECL_ARTIFICIAL (r)))
8448 set_current_access_from_decl (r);
8449 finish_member_declaration (r);
8456 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8458 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8460 tree friend_type = t;
8461 bool adjust_processing_template_decl = false;
8463 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8465 /* template <class T> friend class C; */
8466 friend_type = tsubst_friend_class (friend_type, args);
8467 adjust_processing_template_decl = true;
8469 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8471 /* template <class T> friend class C::D; */
8472 friend_type = tsubst (friend_type, args,
8473 tf_warning_or_error, NULL_TREE);
8474 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8475 friend_type = TREE_TYPE (friend_type);
8476 adjust_processing_template_decl = true;
8478 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8479 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8481 /* This could be either
8485 when dependent_type_p is false or
8487 template <class U> friend class T::C;
8490 friend_type = tsubst (friend_type, args,
8491 tf_warning_or_error, NULL_TREE);
8492 /* Bump processing_template_decl for correct
8493 dependent_type_p calculation. */
8494 ++processing_template_decl;
8495 if (dependent_type_p (friend_type))
8496 adjust_processing_template_decl = true;
8497 --processing_template_decl;
8499 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8500 && hidden_name_p (TYPE_NAME (friend_type)))
8504 where C hasn't been declared yet. Let's lookup name
8505 from namespace scope directly, bypassing any name that
8506 come from dependent base class. */
8507 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8509 /* The call to xref_tag_from_type does injection for friend
8511 push_nested_namespace (ns);
8513 xref_tag_from_type (friend_type, NULL_TREE,
8514 /*tag_scope=*/ts_current);
8515 pop_nested_namespace (ns);
8517 else if (uses_template_parms (friend_type))
8518 /* friend class C<T>; */
8519 friend_type = tsubst (friend_type, args,
8520 tf_warning_or_error, NULL_TREE);
8525 where C is already declared or
8527 friend class C<int>;
8529 We don't have to do anything in these cases. */
8531 if (adjust_processing_template_decl)
8532 /* Trick make_friend_class into realizing that the friend
8533 we're adding is a template, not an ordinary class. It's
8534 important that we use make_friend_class since it will
8535 perform some error-checking and output cross-reference
8537 ++processing_template_decl;
8539 if (friend_type != error_mark_node)
8540 make_friend_class (type, friend_type, /*complain=*/false);
8542 if (adjust_processing_template_decl)
8543 --processing_template_decl;
8547 /* Build new DECL_FRIENDLIST. */
8550 /* The file and line for this declaration, to
8551 assist in error message reporting. Since we
8552 called push_tinst_level above, we don't need to
8554 input_location = DECL_SOURCE_LOCATION (t);
8556 if (TREE_CODE (t) == TEMPLATE_DECL)
8558 ++processing_template_decl;
8559 push_deferring_access_checks (dk_no_check);
8562 r = tsubst_friend_function (t, args);
8563 add_friend (type, r, /*complain=*/false);
8564 if (TREE_CODE (t) == TEMPLATE_DECL)
8566 pop_deferring_access_checks ();
8567 --processing_template_decl;
8573 if (CLASSTYPE_LAMBDA_EXPR (type))
8574 maybe_add_lambda_conv_op (type);
8576 /* Set the file and line number information to whatever is given for
8577 the class itself. This puts error messages involving generated
8578 implicit functions at a predictable point, and the same point
8579 that would be used for non-template classes. */
8580 input_location = DECL_SOURCE_LOCATION (typedecl);
8582 unreverse_member_declarations (type);
8583 finish_struct_1 (type);
8584 TYPE_BEING_DEFINED (type) = 0;
8586 /* We don't instantiate default arguments for member functions. 14.7.1:
8588 The implicit instantiation of a class template specialization causes
8589 the implicit instantiation of the declarations, but not of the
8590 definitions or default arguments, of the class member functions,
8591 member classes, static data members and member templates.... */
8593 /* Some typedefs referenced from within the template code need to be access
8594 checked at template instantiation time, i.e now. These types were
8595 added to the template at parsing time. Let's get those and perform
8596 the access checks then. */
8597 perform_typedefs_access_check (pattern, args);
8598 perform_deferred_access_checks ();
8599 pop_nested_class ();
8600 maximum_field_alignment = saved_maximum_field_alignment;
8601 pop_from_top_level ();
8602 pop_deferring_access_checks ();
8605 /* The vtable for a template class can be emitted in any translation
8606 unit in which the class is instantiated. When there is no key
8607 method, however, finish_struct_1 will already have added TYPE to
8608 the keyed_classes list. */
8609 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8610 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8615 /* Wrapper for instantiate_class_template_1. */
8618 instantiate_class_template (tree type)
8621 timevar_push (TV_TEMPLATE_INST);
8622 ret = instantiate_class_template_1 (type);
8623 timevar_pop (TV_TEMPLATE_INST);
8628 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8634 else if (TYPE_P (t))
8635 r = tsubst (t, args, complain, in_decl);
8638 if (!(complain & tf_warning))
8639 ++c_inhibit_evaluation_warnings;
8640 r = tsubst_expr (t, args, complain, in_decl,
8641 /*integral_constant_expression_p=*/true);
8642 if (!(complain & tf_warning))
8643 --c_inhibit_evaluation_warnings;
8648 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8649 NONTYPE_ARGUMENT_PACK. */
8652 make_fnparm_pack (tree spec_parm)
8654 /* Collect all of the extra "packed" parameters into an
8658 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8659 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8660 int i, len = list_length (spec_parm);
8662 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8663 parmvec = make_tree_vec (len);
8664 parmtypevec = make_tree_vec (len);
8665 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8667 TREE_VEC_ELT (parmvec, i) = spec_parm;
8668 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8671 /* Build the argument packs. */
8672 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8673 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8674 TREE_TYPE (argpack) = argtypepack;
8679 /* Substitute ARGS into T, which is an pack expansion
8680 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8681 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8682 (if only a partial substitution could be performed) or
8683 ERROR_MARK_NODE if there was an error. */
8685 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8689 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8693 htab_t saved_local_specializations = NULL;
8695 gcc_assert (PACK_EXPANSION_P (t));
8696 pattern = PACK_EXPANSION_PATTERN (t);
8698 /* Determine the argument packs that will instantiate the parameter
8699 packs used in the expansion expression. While we're at it,
8700 compute the number of arguments to be expanded and make sure it
8702 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8703 pack = TREE_CHAIN (pack))
8705 tree parm_pack = TREE_VALUE (pack);
8706 tree arg_pack = NULL_TREE;
8707 tree orig_arg = NULL_TREE;
8709 if (TREE_CODE (parm_pack) == PARM_DECL)
8711 if (!cp_unevaluated_operand)
8712 arg_pack = retrieve_local_specialization (parm_pack);
8715 /* We can't rely on local_specializations for a parameter
8716 name used later in a function declaration (such as in a
8717 late-specified return type). Even if it exists, it might
8718 have the wrong value for a recursive call. Just make a
8719 dummy decl, since it's only used for its type. */
8720 arg_pack = tsubst_decl (parm_pack, args, complain);
8721 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
8722 /* Partial instantiation of the parm_pack, we can't build
8723 up an argument pack yet. */
8724 arg_pack = NULL_TREE;
8726 arg_pack = make_fnparm_pack (arg_pack);
8731 int level, idx, levels;
8732 template_parm_level_and_index (parm_pack, &level, &idx);
8734 levels = TMPL_ARGS_DEPTH (args);
8735 if (level <= levels)
8736 arg_pack = TMPL_ARG (args, level, idx);
8739 orig_arg = arg_pack;
8740 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8741 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8743 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8744 /* This can only happen if we forget to expand an argument
8745 pack somewhere else. Just return an error, silently. */
8747 result = make_tree_vec (1);
8748 TREE_VEC_ELT (result, 0) = error_mark_node;
8752 /* For clarity in the comments below let's use the
8753 representation 'argument_pack<elements>' to denote an
8754 argument pack and its elements.
8756 In the 'if' block below, we want to detect cases where
8757 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
8758 check if ARG_PACK is an argument pack which sole element is
8759 the expansion of PARM_PACK. That argument pack is typically
8760 created by template_parm_to_arg when passed a parameter
8763 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8764 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8766 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8767 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8768 /* So we have an argument_pack<P...>. We want to test if P
8769 is actually PARM_PACK. We will not use cp_tree_equal to
8770 test P and PARM_PACK because during type fixup (by
8771 fixup_template_parm) P can be a pre-fixup version of a
8772 type and PARM_PACK be its post-fixup version.
8773 cp_tree_equal would consider them as different even
8774 though we would want to consider them compatible for our
8775 precise purpose here.
8777 Thus we are going to consider that P and PARM_PACK are
8778 compatible if they have the same DECL. */
8779 if ((/* If ARG_PACK is a type parameter pack named by the
8780 same DECL as parm_pack ... */
8782 && TYPE_P (parm_pack)
8783 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
8784 /* ... or if ARG_PACK is a non-type parameter
8785 named by the same DECL as parm_pack ... */
8786 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
8787 && TREE_CODE (parm_pack) == PARM_DECL
8788 && TEMPLATE_PARM_DECL (pattern)
8789 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
8790 && template_parameter_pack_p (pattern))
8791 /* ... then the argument pack that the parameter maps to
8792 is just an expansion of the parameter itself, such as
8793 one would find in the implicit typedef of a class
8794 inside the class itself. Consider this parameter
8795 "unsubstituted", so that we will maintain the outer
8797 arg_pack = NULL_TREE;
8803 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8805 /* It's all-or-nothing with incomplete argument packs. */
8806 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8807 return error_mark_node;
8809 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8814 else if (len != my_len)
8817 /* We got explicit args for some packs but not others;
8818 do nothing now and try again after deduction. */
8820 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8821 error ("mismatched argument pack lengths while expanding "
8825 error ("mismatched argument pack lengths while expanding "
8828 return error_mark_node;
8831 /* Keep track of the parameter packs and their corresponding
8833 packs = tree_cons (parm_pack, arg_pack, packs);
8834 TREE_TYPE (packs) = orig_arg;
8837 /* We can't substitute for this parameter pack. */
8838 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8840 unsubstituted_packs);
8843 /* We cannot expand this expansion expression, because we don't have
8844 all of the argument packs we need. Substitute into the pattern
8845 and return a PACK_EXPANSION_*. The caller will need to deal with
8847 if (unsubstituted_packs)
8850 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8851 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8852 /*integral_constant_expression_p=*/false);
8854 new_pat = tsubst (pattern, args, complain, in_decl);
8855 return make_pack_expansion (new_pat);
8858 /* We could not find any argument packs that work. */
8860 return error_mark_node;
8862 if (cp_unevaluated_operand)
8864 /* We're in a late-specified return type, so create our own local
8865 specializations table; the current table is either NULL or (in the
8866 case of recursive unification) might have bindings that we don't
8867 want to use or alter. */
8868 saved_local_specializations = local_specializations;
8869 local_specializations = htab_create (37,
8870 hash_local_specialization,
8871 eq_local_specializations,
8875 /* For each argument in each argument pack, substitute into the
8877 result = make_tree_vec (len + incomplete);
8878 for (i = 0; i < len + incomplete; ++i)
8880 /* For parameter pack, change the substitution of the parameter
8881 pack to the ith argument in its argument pack, then expand
8883 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8885 tree parm = TREE_PURPOSE (pack);
8887 if (TREE_CODE (parm) == PARM_DECL)
8889 /* Select the Ith argument from the pack. */
8890 tree arg = make_node (ARGUMENT_PACK_SELECT);
8891 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8892 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8894 register_local_specialization (arg, parm);
8900 template_parm_level_and_index (parm, &level, &idx);
8904 /* Select the Ith argument from the pack. */
8905 value = make_node (ARGUMENT_PACK_SELECT);
8906 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8907 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8910 /* Update the corresponding argument. */
8911 TMPL_ARG (args, level, idx) = value;
8915 /* Substitute into the PATTERN with the altered arguments. */
8916 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8917 TREE_VEC_ELT (result, i) =
8918 tsubst_expr (pattern, args, complain, in_decl,
8919 /*integral_constant_expression_p=*/false);
8921 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8924 /* When we have incomplete argument packs, the last "expanded"
8925 result is itself a pack expansion, which allows us
8926 to deduce more arguments. */
8927 TREE_VEC_ELT (result, i) =
8928 make_pack_expansion (TREE_VEC_ELT (result, i));
8930 if (TREE_VEC_ELT (result, i) == error_mark_node)
8932 result = error_mark_node;
8937 /* Update ARGS to restore the substitution from parameter packs to
8938 their argument packs. */
8939 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8941 tree parm = TREE_PURPOSE (pack);
8943 if (TREE_CODE (parm) == PARM_DECL)
8944 register_local_specialization (TREE_TYPE (pack), parm);
8948 template_parm_level_and_index (parm, &level, &idx);
8950 /* Update the corresponding argument. */
8951 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8952 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8955 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8959 if (saved_local_specializations)
8961 htab_delete (local_specializations);
8962 local_specializations = saved_local_specializations;
8968 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8969 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8970 parameter packs; all parms generated from a function parameter pack will
8971 have the same DECL_PARM_INDEX. */
8974 get_pattern_parm (tree parm, tree tmpl)
8976 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8979 if (DECL_ARTIFICIAL (parm))
8981 for (patparm = DECL_ARGUMENTS (pattern);
8982 patparm; patparm = DECL_CHAIN (patparm))
8983 if (DECL_ARTIFICIAL (patparm)
8984 && DECL_NAME (parm) == DECL_NAME (patparm))
8989 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8990 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8991 gcc_assert (DECL_PARM_INDEX (patparm)
8992 == DECL_PARM_INDEX (parm));
8998 /* Substitute ARGS into the vector or list of template arguments T. */
9001 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9004 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9007 if (t == error_mark_node)
9008 return error_mark_node;
9010 len = TREE_VEC_LENGTH (t);
9011 elts = XALLOCAVEC (tree, len);
9013 for (i = 0; i < len; i++)
9015 tree orig_arg = TREE_VEC_ELT (t, i);
9018 if (TREE_CODE (orig_arg) == TREE_VEC)
9019 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9020 else if (PACK_EXPANSION_P (orig_arg))
9022 /* Substitute into an expansion expression. */
9023 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9025 if (TREE_CODE (new_arg) == TREE_VEC)
9026 /* Add to the expanded length adjustment the number of
9027 expanded arguments. We subtract one from this
9028 measurement, because the argument pack expression
9029 itself is already counted as 1 in
9030 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9031 the argument pack is empty. */
9032 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9034 else if (ARGUMENT_PACK_P (orig_arg))
9036 /* Substitute into each of the arguments. */
9037 new_arg = TYPE_P (orig_arg)
9038 ? cxx_make_type (TREE_CODE (orig_arg))
9039 : make_node (TREE_CODE (orig_arg));
9041 SET_ARGUMENT_PACK_ARGS (
9043 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9044 args, complain, in_decl));
9046 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9047 new_arg = error_mark_node;
9049 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9050 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9052 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9054 if (TREE_TYPE (new_arg) == error_mark_node)
9055 new_arg = error_mark_node;
9059 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9061 if (new_arg == error_mark_node)
9062 return error_mark_node;
9065 if (new_arg != orig_arg)
9072 /* Make space for the expanded arguments coming from template
9074 t = make_tree_vec (len + expanded_len_adjust);
9075 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9076 arguments for a member template.
9077 In that case each TREE_VEC in ORIG_T represents a level of template
9078 arguments, and ORIG_T won't carry any non defaulted argument count.
9079 It will rather be the nested TREE_VECs that will carry one.
9080 In other words, ORIG_T carries a non defaulted argument count only
9081 if it doesn't contain any nested TREE_VEC. */
9082 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9084 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9085 count += expanded_len_adjust;
9086 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9088 for (i = 0, out = 0; i < len; i++)
9090 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9091 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9092 && TREE_CODE (elts[i]) == TREE_VEC)
9096 /* Now expand the template argument pack "in place". */
9097 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9098 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9102 TREE_VEC_ELT (t, out) = elts[i];
9110 /* Return the result of substituting ARGS into the template parameters
9111 given by PARMS. If there are m levels of ARGS and m + n levels of
9112 PARMS, then the result will contain n levels of PARMS. For
9113 example, if PARMS is `template <class T> template <class U>
9114 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9115 result will be `template <int*, double, class V>'. */
9118 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9123 /* When substituting into a template, we must set
9124 PROCESSING_TEMPLATE_DECL as the template parameters may be
9125 dependent if they are based on one-another, and the dependency
9126 predicates are short-circuit outside of templates. */
9127 ++processing_template_decl;
9129 for (new_parms = &r;
9130 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9131 new_parms = &(TREE_CHAIN (*new_parms)),
9132 parms = TREE_CHAIN (parms))
9135 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9138 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9142 if (parms == error_mark_node)
9145 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9147 if (tuple == error_mark_node)
9150 TREE_VEC_ELT (new_vec, i) =
9151 tsubst_template_parm (tuple, args, complain);
9155 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9156 - TMPL_ARGS_DEPTH (args)),
9157 new_vec, NULL_TREE);
9160 --processing_template_decl;
9165 /* Return the result of substituting ARGS into one template parameter
9166 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9167 parameter and which TREE_PURPOSE is the default argument of the
9168 template parameter. */
9171 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9173 tree default_value, parm_decl;
9175 if (args == NULL_TREE
9177 || t == error_mark_node)
9180 gcc_assert (TREE_CODE (t) == TREE_LIST);
9182 default_value = TREE_PURPOSE (t);
9183 parm_decl = TREE_VALUE (t);
9185 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9186 if (TREE_CODE (parm_decl) == PARM_DECL
9187 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9188 parm_decl = error_mark_node;
9189 default_value = tsubst_template_arg (default_value, args,
9190 complain, NULL_TREE);
9192 return build_tree_list (default_value, parm_decl);
9195 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9196 type T. If T is not an aggregate or enumeration type, it is
9197 handled as if by tsubst. IN_DECL is as for tsubst. If
9198 ENTERING_SCOPE is nonzero, T is the context for a template which
9199 we are presently tsubst'ing. Return the substituted value. */
9202 tsubst_aggr_type (tree t,
9204 tsubst_flags_t complain,
9211 switch (TREE_CODE (t))
9214 if (TYPE_PTRMEMFUNC_P (t))
9215 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9217 /* Else fall through. */
9220 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9225 int saved_unevaluated_operand;
9226 int saved_inhibit_evaluation_warnings;
9228 /* In "sizeof(X<I>)" we need to evaluate "I". */
9229 saved_unevaluated_operand = cp_unevaluated_operand;
9230 cp_unevaluated_operand = 0;
9231 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9232 c_inhibit_evaluation_warnings = 0;
9234 /* First, determine the context for the type we are looking
9236 context = TYPE_CONTEXT (t);
9239 context = tsubst_aggr_type (context, args, complain,
9240 in_decl, /*entering_scope=*/1);
9241 /* If context is a nested class inside a class template,
9242 it may still need to be instantiated (c++/33959). */
9243 if (TYPE_P (context))
9244 context = complete_type (context);
9247 /* Then, figure out what arguments are appropriate for the
9248 type we are trying to find. For example, given:
9250 template <class T> struct S;
9251 template <class T, class U> void f(T, U) { S<U> su; }
9253 and supposing that we are instantiating f<int, double>,
9254 then our ARGS will be {int, double}, but, when looking up
9255 S we only want {double}. */
9256 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9258 if (argvec == error_mark_node)
9259 r = error_mark_node;
9262 r = lookup_template_class (t, argvec, in_decl, context,
9263 entering_scope, complain);
9264 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9267 cp_unevaluated_operand = saved_unevaluated_operand;
9268 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9273 /* This is not a template type, so there's nothing to do. */
9277 return tsubst (t, args, complain, in_decl);
9281 /* Substitute into the default argument ARG (a default argument for
9282 FN), which has the indicated TYPE. */
9285 tsubst_default_argument (tree fn, tree type, tree arg)
9287 tree saved_class_ptr = NULL_TREE;
9288 tree saved_class_ref = NULL_TREE;
9290 /* This can happen in invalid code. */
9291 if (TREE_CODE (arg) == DEFAULT_ARG)
9294 /* This default argument came from a template. Instantiate the
9295 default argument here, not in tsubst. In the case of
9304 we must be careful to do name lookup in the scope of S<T>,
9305 rather than in the current class. */
9306 push_access_scope (fn);
9307 /* The "this" pointer is not valid in a default argument. */
9310 saved_class_ptr = current_class_ptr;
9311 cp_function_chain->x_current_class_ptr = NULL_TREE;
9312 saved_class_ref = current_class_ref;
9313 cp_function_chain->x_current_class_ref = NULL_TREE;
9316 push_deferring_access_checks(dk_no_deferred);
9317 /* The default argument expression may cause implicitly defined
9318 member functions to be synthesized, which will result in garbage
9319 collection. We must treat this situation as if we were within
9320 the body of function so as to avoid collecting live data on the
9323 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9324 tf_warning_or_error, NULL_TREE,
9325 /*integral_constant_expression_p=*/false);
9327 pop_deferring_access_checks();
9329 /* Restore the "this" pointer. */
9332 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9333 cp_function_chain->x_current_class_ref = saved_class_ref;
9336 /* Make sure the default argument is reasonable. */
9337 arg = check_default_argument (type, arg);
9339 pop_access_scope (fn);
9344 /* Substitute into all the default arguments for FN. */
9347 tsubst_default_arguments (tree fn)
9352 tmpl_args = DECL_TI_ARGS (fn);
9354 /* If this function is not yet instantiated, we certainly don't need
9355 its default arguments. */
9356 if (uses_template_parms (tmpl_args))
9358 /* Don't do this again for clones. */
9359 if (DECL_CLONED_FUNCTION_P (fn))
9362 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9364 arg = TREE_CHAIN (arg))
9365 if (TREE_PURPOSE (arg))
9366 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9368 TREE_PURPOSE (arg));
9371 /* Substitute the ARGS into the T, which is a _DECL. Return the
9372 result of the substitution. Issue error and warning messages under
9373 control of COMPLAIN. */
9376 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9378 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9379 location_t saved_loc;
9384 /* Set the filename and linenumber to improve error-reporting. */
9385 saved_loc = input_location;
9386 input_location = DECL_SOURCE_LOCATION (t);
9388 switch (TREE_CODE (t))
9392 /* We can get here when processing a member function template,
9393 member class template, or template template parameter. */
9394 tree decl = DECL_TEMPLATE_RESULT (t);
9399 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9401 /* Template template parameter is treated here. */
9402 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9403 if (new_type == error_mark_node)
9404 RETURN (error_mark_node);
9407 DECL_CHAIN (r) = NULL_TREE;
9408 TREE_TYPE (r) = new_type;
9409 DECL_TEMPLATE_RESULT (r)
9410 = build_decl (DECL_SOURCE_LOCATION (decl),
9411 TYPE_DECL, DECL_NAME (decl), new_type);
9412 DECL_TEMPLATE_PARMS (r)
9413 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9415 TYPE_NAME (new_type) = r;
9419 /* We might already have an instance of this template.
9420 The ARGS are for the surrounding class type, so the
9421 full args contain the tsubst'd args for the context,
9422 plus the innermost args from the template decl. */
9423 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9424 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9425 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9426 /* Because this is a template, the arguments will still be
9427 dependent, even after substitution. If
9428 PROCESSING_TEMPLATE_DECL is not set, the dependency
9429 predicates will short-circuit. */
9430 ++processing_template_decl;
9431 full_args = tsubst_template_args (tmpl_args, args,
9433 --processing_template_decl;
9434 if (full_args == error_mark_node)
9435 RETURN (error_mark_node);
9437 /* If this is a default template template argument,
9438 tsubst might not have changed anything. */
9439 if (full_args == tmpl_args)
9442 hash = hash_tmpl_and_args (t, full_args);
9443 spec = retrieve_specialization (t, full_args, hash);
9444 if (spec != NULL_TREE)
9450 /* Make a new template decl. It will be similar to the
9451 original, but will record the current template arguments.
9452 We also create a new function declaration, which is just
9453 like the old one, but points to this new template, rather
9454 than the old one. */
9456 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9457 DECL_CHAIN (r) = NULL_TREE;
9459 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9461 if (TREE_CODE (decl) == TYPE_DECL)
9464 ++processing_template_decl;
9465 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9466 --processing_template_decl;
9467 if (new_type == error_mark_node)
9468 RETURN (error_mark_node);
9470 TREE_TYPE (r) = new_type;
9471 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9472 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9473 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9474 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9479 ++processing_template_decl;
9480 new_decl = tsubst (decl, args, complain, in_decl);
9481 --processing_template_decl;
9482 if (new_decl == error_mark_node)
9483 RETURN (error_mark_node);
9485 DECL_TEMPLATE_RESULT (r) = new_decl;
9486 DECL_TI_TEMPLATE (new_decl) = r;
9487 TREE_TYPE (r) = TREE_TYPE (new_decl);
9488 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9489 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9492 SET_DECL_IMPLICIT_INSTANTIATION (r);
9493 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9494 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9496 /* The template parameters for this new template are all the
9497 template parameters for the old template, except the
9498 outermost level of parameters. */
9499 DECL_TEMPLATE_PARMS (r)
9500 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9503 if (PRIMARY_TEMPLATE_P (t))
9504 DECL_PRIMARY_TEMPLATE (r) = r;
9506 if (TREE_CODE (decl) != TYPE_DECL)
9507 /* Record this non-type partial instantiation. */
9508 register_specialization (r, t,
9509 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9517 tree argvec = NULL_TREE;
9525 /* Nobody should be tsubst'ing into non-template functions. */
9526 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9528 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9533 /* If T is not dependent, just return it. We have to
9534 increment PROCESSING_TEMPLATE_DECL because
9535 value_dependent_expression_p assumes that nothing is
9536 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9537 ++processing_template_decl;
9538 dependent_p = value_dependent_expression_p (t);
9539 --processing_template_decl;
9543 /* Calculate the most general template of which R is a
9544 specialization, and the complete set of arguments used to
9546 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9547 argvec = tsubst_template_args (DECL_TI_ARGS
9548 (DECL_TEMPLATE_RESULT
9549 (DECL_TI_TEMPLATE (t))),
9550 args, complain, in_decl);
9552 /* Check to see if we already have this specialization. */
9553 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9554 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9562 /* We can see more levels of arguments than parameters if
9563 there was a specialization of a member template, like
9566 template <class T> struct S { template <class U> void f(); }
9567 template <> template <class U> void S<int>::f(U);
9569 Here, we'll be substituting into the specialization,
9570 because that's where we can find the code we actually
9571 want to generate, but we'll have enough arguments for
9572 the most general template.
9574 We also deal with the peculiar case:
9576 template <class T> struct S {
9577 template <class U> friend void f();
9579 template <class U> void f() {}
9581 template void f<double>();
9583 Here, the ARGS for the instantiation of will be {int,
9584 double}. But, we only need as many ARGS as there are
9585 levels of template parameters in CODE_PATTERN. We are
9586 careful not to get fooled into reducing the ARGS in
9589 template <class T> struct S { template <class U> void f(U); }
9590 template <class T> template <> void S<T>::f(int) {}
9592 which we can spot because the pattern will be a
9593 specialization in this case. */
9594 args_depth = TMPL_ARGS_DEPTH (args);
9596 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9597 if (args_depth > parms_depth
9598 && !DECL_TEMPLATE_SPECIALIZATION (t))
9599 args = get_innermost_template_args (args, parms_depth);
9603 /* This special case arises when we have something like this:
9605 template <class T> struct S {
9606 friend void f<int>(int, double);
9609 Here, the DECL_TI_TEMPLATE for the friend declaration
9610 will be an IDENTIFIER_NODE. We are being called from
9611 tsubst_friend_function, and we want only to create a
9612 new decl (R) with appropriate types so that we can call
9613 determine_specialization. */
9614 gen_tmpl = NULL_TREE;
9617 if (DECL_CLASS_SCOPE_P (t))
9619 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9623 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9624 complain, t, /*entering_scope=*/1);
9629 ctx = DECL_CONTEXT (t);
9631 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9632 if (type == error_mark_node)
9633 RETURN (error_mark_node);
9635 /* We do NOT check for matching decls pushed separately at this
9636 point, as they may not represent instantiations of this
9637 template, and in any case are considered separate under the
9640 DECL_USE_TEMPLATE (r) = 0;
9641 TREE_TYPE (r) = type;
9642 /* Clear out the mangled name and RTL for the instantiation. */
9643 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9644 SET_DECL_RTL (r, NULL);
9645 /* Leave DECL_INITIAL set on deleted instantiations. */
9646 if (!DECL_DELETED_FN (r))
9647 DECL_INITIAL (r) = NULL_TREE;
9648 DECL_CONTEXT (r) = ctx;
9650 if (member && DECL_CONV_FN_P (r))
9651 /* Type-conversion operator. Reconstruct the name, in
9652 case it's the name of one of the template's parameters. */
9653 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9655 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9657 DECL_RESULT (r) = NULL_TREE;
9659 TREE_STATIC (r) = 0;
9660 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9661 DECL_EXTERNAL (r) = 1;
9662 /* If this is an instantiation of a function with internal
9663 linkage, we already know what object file linkage will be
9664 assigned to the instantiation. */
9665 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9666 DECL_DEFER_OUTPUT (r) = 0;
9667 DECL_CHAIN (r) = NULL_TREE;
9668 DECL_PENDING_INLINE_INFO (r) = 0;
9669 DECL_PENDING_INLINE_P (r) = 0;
9670 DECL_SAVED_TREE (r) = NULL_TREE;
9671 DECL_STRUCT_FUNCTION (r) = NULL;
9673 /* We'll re-clone as appropriate in instantiate_template. */
9674 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9676 /* If we aren't complaining now, return on error before we register
9677 the specialization so that we'll complain eventually. */
9678 if ((complain & tf_error) == 0
9679 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9680 && !grok_op_properties (r, /*complain=*/false))
9681 RETURN (error_mark_node);
9683 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9684 this in the special friend case mentioned above where
9685 GEN_TMPL is NULL. */
9688 DECL_TEMPLATE_INFO (r)
9689 = build_template_info (gen_tmpl, argvec);
9690 SET_DECL_IMPLICIT_INSTANTIATION (r);
9691 register_specialization (r, gen_tmpl, argvec, false, hash);
9693 /* We're not supposed to instantiate default arguments
9694 until they are called, for a template. But, for a
9697 template <class T> void f ()
9698 { extern void g(int i = T()); }
9700 we should do the substitution when the template is
9701 instantiated. We handle the member function case in
9702 instantiate_class_template since the default arguments
9703 might refer to other members of the class. */
9705 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9706 && !uses_template_parms (argvec))
9707 tsubst_default_arguments (r);
9710 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9712 /* Copy the list of befriending classes. */
9713 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9715 friends = &TREE_CHAIN (*friends))
9717 *friends = copy_node (*friends);
9718 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9723 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9725 maybe_retrofit_in_chrg (r);
9726 if (DECL_CONSTRUCTOR_P (r))
9727 grok_ctor_properties (ctx, r);
9728 /* If this is an instantiation of a member template, clone it.
9729 If it isn't, that'll be handled by
9730 clone_constructors_and_destructors. */
9731 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9732 clone_function_decl (r, /*update_method_vec_p=*/0);
9734 else if ((complain & tf_error) != 0
9735 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9736 && !grok_op_properties (r, /*complain=*/true))
9737 RETURN (error_mark_node);
9739 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9740 SET_DECL_FRIEND_CONTEXT (r,
9741 tsubst (DECL_FRIEND_CONTEXT (t),
9742 args, complain, in_decl));
9744 /* Possibly limit visibility based on template args. */
9745 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9746 if (DECL_VISIBILITY_SPECIFIED (t))
9748 DECL_VISIBILITY_SPECIFIED (r) = 0;
9750 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9752 determine_visibility (r);
9753 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9754 && !processing_template_decl)
9755 defaulted_late_check (r);
9757 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9758 args, complain, in_decl);
9764 tree type = NULL_TREE;
9766 tree expanded_types = NULL_TREE;
9767 tree prev_r = NULL_TREE;
9768 tree first_r = NULL_TREE;
9770 if (FUNCTION_PARAMETER_PACK_P (t))
9772 /* If there is a local specialization that isn't a
9773 parameter pack, it means that we're doing a "simple"
9774 substitution from inside tsubst_pack_expansion. Just
9775 return the local specialization (which will be a single
9777 tree spec = retrieve_local_specialization (t);
9779 && TREE_CODE (spec) == PARM_DECL
9780 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9783 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9784 the parameters in this function parameter pack. */
9785 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9787 if (TREE_CODE (expanded_types) == TREE_VEC)
9789 len = TREE_VEC_LENGTH (expanded_types);
9791 /* Zero-length parameter packs are boring. Just substitute
9794 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9799 /* All we did was update the type. Make a note of that. */
9800 type = expanded_types;
9801 expanded_types = NULL_TREE;
9805 /* Loop through all of the parameter's we'll build. When T is
9806 a function parameter pack, LEN is the number of expanded
9807 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9809 for (i = 0; i < len; ++i)
9813 if (DECL_TEMPLATE_PARM_P (t))
9814 SET_DECL_TEMPLATE_PARM_P (r);
9817 /* We're on the Ith parameter of the function parameter
9820 /* An argument of a function parameter pack is not a parameter
9822 FUNCTION_PARAMETER_PACK_P (r) = false;
9824 /* Get the Ith type. */
9825 type = TREE_VEC_ELT (expanded_types, i);
9828 /* Rename the parameter to include the index. */
9830 make_ith_pack_parameter_name (DECL_NAME (r), i);
9833 /* We're dealing with a normal parameter. */
9834 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9836 type = type_decays_to (type);
9837 TREE_TYPE (r) = type;
9838 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9840 if (DECL_INITIAL (r))
9842 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9843 DECL_INITIAL (r) = TREE_TYPE (r);
9845 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9849 DECL_CONTEXT (r) = NULL_TREE;
9851 if (!DECL_TEMPLATE_PARM_P (r))
9852 DECL_ARG_TYPE (r) = type_passed_as (type);
9854 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9855 args, complain, in_decl);
9857 /* Keep track of the first new parameter we
9858 generate. That's what will be returned to the
9863 /* Build a proper chain of parameters when substituting
9864 into a function parameter pack. */
9866 DECL_CHAIN (prev_r) = r;
9870 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9871 complain, DECL_CHAIN (t));
9873 /* FIRST_R contains the start of the chain we've built. */
9883 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9884 if (type == error_mark_node)
9885 RETURN (error_mark_node);
9886 TREE_TYPE (r) = type;
9887 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9889 /* DECL_INITIAL gives the number of bits in a bit-field. */
9891 = tsubst_expr (DECL_INITIAL (t), args,
9893 /*integral_constant_expression_p=*/true);
9894 /* We don't have to set DECL_CONTEXT here; it is set by
9895 finish_member_declaration. */
9896 DECL_CHAIN (r) = NULL_TREE;
9897 if (VOID_TYPE_P (type))
9898 error ("instantiation of %q+D as type %qT", r, type);
9900 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9901 args, complain, in_decl);
9906 /* We reach here only for member using decls. */
9907 if (DECL_DEPENDENT_P (t))
9909 r = do_class_using_decl
9910 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9911 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9913 r = error_mark_node;
9916 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9917 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9923 DECL_CHAIN (r) = NULL_TREE;
9930 tree argvec = NULL_TREE;
9931 tree gen_tmpl = NULL_TREE;
9933 tree tmpl = NULL_TREE;
9935 tree type = NULL_TREE;
9938 if (TREE_CODE (t) == TYPE_DECL
9939 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9941 /* If this is the canonical decl, we don't have to
9942 mess with instantiations, and often we can't (for
9943 typename, template type parms and such). Note that
9944 TYPE_NAME is not correct for the above test if
9945 we've copied the type for a typedef. */
9946 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9947 if (type == error_mark_node)
9948 RETURN (error_mark_node);
9949 r = TYPE_NAME (type);
9953 /* Check to see if we already have the specialization we
9956 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9958 /* T is a static data member or namespace-scope entity.
9959 We have to substitute into namespace-scope variables
9960 (even though such entities are never templates) because
9963 template <class T> void f() { extern T t; }
9965 where the entity referenced is not known until
9966 instantiation time. */
9968 ctx = DECL_CONTEXT (t);
9969 if (DECL_CLASS_SCOPE_P (t))
9971 ctx = tsubst_aggr_type (ctx, args,
9973 in_decl, /*entering_scope=*/1);
9974 /* If CTX is unchanged, then T is in fact the
9975 specialization we want. That situation occurs when
9976 referencing a static data member within in its own
9977 class. We can use pointer equality, rather than
9978 same_type_p, because DECL_CONTEXT is always
9980 if (ctx == DECL_CONTEXT (t))
9986 tmpl = DECL_TI_TEMPLATE (t);
9987 gen_tmpl = most_general_template (tmpl);
9988 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9989 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9990 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9995 /* A local variable. */
9997 /* Subsequent calls to pushdecl will fill this in. */
9999 spec = retrieve_local_specialization (t);
10001 /* If we already have the specialization we need, there is
10002 nothing more to do. */
10009 /* Create a new node for the specialization we need. */
10011 if (type == NULL_TREE)
10013 if (is_typedef_decl (t))
10014 type = DECL_ORIGINAL_TYPE (t);
10016 type = TREE_TYPE (t);
10017 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10018 type = strip_array_domain (type);
10019 type = tsubst (type, args, complain, in_decl);
10021 if (TREE_CODE (r) == VAR_DECL)
10023 /* Even if the original location is out of scope, the
10024 newly substituted one is not. */
10025 DECL_DEAD_FOR_LOCAL (r) = 0;
10026 DECL_INITIALIZED_P (r) = 0;
10027 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10028 if (type == error_mark_node)
10029 RETURN (error_mark_node);
10030 if (TREE_CODE (type) == FUNCTION_TYPE)
10032 /* It may seem that this case cannot occur, since:
10037 declares a function, not a variable. However:
10040 template <typename T> void g() { T t; }
10041 template void g<f>();
10043 is an attempt to declare a variable with function
10045 error ("variable %qD has function type",
10046 /* R is not yet sufficiently initialized, so we
10047 just use its name. */
10049 RETURN (error_mark_node);
10051 type = complete_type (type);
10052 /* Wait until cp_finish_decl to set this again, to handle
10053 circular dependency (template/instantiate6.C). */
10054 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10055 type = check_var_type (DECL_NAME (r), type);
10057 if (DECL_HAS_VALUE_EXPR_P (t))
10059 tree ve = DECL_VALUE_EXPR (t);
10060 ve = tsubst_expr (ve, args, complain, in_decl,
10061 /*constant_expression_p=*/false);
10062 SET_DECL_VALUE_EXPR (r, ve);
10065 else if (DECL_SELF_REFERENCE_P (t))
10066 SET_DECL_SELF_REFERENCE_P (r);
10067 TREE_TYPE (r) = type;
10068 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10069 DECL_CONTEXT (r) = ctx;
10070 /* Clear out the mangled name and RTL for the instantiation. */
10071 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10072 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10073 SET_DECL_RTL (r, NULL);
10074 /* The initializer must not be expanded until it is required;
10075 see [temp.inst]. */
10076 DECL_INITIAL (r) = NULL_TREE;
10077 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10078 SET_DECL_RTL (r, NULL);
10079 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10080 if (TREE_CODE (r) == VAR_DECL)
10082 /* Possibly limit visibility based on template args. */
10083 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10084 if (DECL_VISIBILITY_SPECIFIED (t))
10086 DECL_VISIBILITY_SPECIFIED (r) = 0;
10087 DECL_ATTRIBUTES (r)
10088 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10090 determine_visibility (r);
10095 /* A static data member declaration is always marked
10096 external when it is declared in-class, even if an
10097 initializer is present. We mimic the non-template
10098 processing here. */
10099 DECL_EXTERNAL (r) = 1;
10101 register_specialization (r, gen_tmpl, argvec, false, hash);
10102 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10103 SET_DECL_IMPLICIT_INSTANTIATION (r);
10105 else if (cp_unevaluated_operand)
10107 /* We're substituting this var in a decltype outside of its
10108 scope, such as for a lambda return type. Don't add it to
10109 local_specializations, do perform auto deduction. */
10110 tree auto_node = type_uses_auto (type);
10112 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10113 /*constant_expression_p=*/false);
10115 if (auto_node && init)
10117 init = resolve_nondeduced_context (init);
10118 if (describable_type (init))
10120 type = do_auto_deduction (type, init, auto_node);
10121 TREE_TYPE (r) = type;
10126 register_local_specialization (r, t);
10128 DECL_CHAIN (r) = NULL_TREE;
10130 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10132 args, complain, in_decl);
10134 /* Preserve a typedef that names a type. */
10135 if (is_typedef_decl (r))
10137 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10138 set_underlying_type (r);
10141 layout_decl (r, 0);
10146 gcc_unreachable ();
10151 /* Restore the file and line information. */
10152 input_location = saved_loc;
10157 /* Substitute into the ARG_TYPES of a function type. */
10160 tsubst_arg_types (tree arg_types,
10162 tsubst_flags_t complain,
10165 tree remaining_arg_types;
10166 tree type = NULL_TREE;
10168 tree expanded_args = NULL_TREE;
10171 if (!arg_types || arg_types == void_list_node)
10174 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10175 args, complain, in_decl);
10176 if (remaining_arg_types == error_mark_node)
10177 return error_mark_node;
10179 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10181 /* For a pack expansion, perform substitution on the
10182 entire expression. Later on, we'll handle the arguments
10184 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10185 args, complain, in_decl);
10187 if (TREE_CODE (expanded_args) == TREE_VEC)
10188 /* So that we'll spin through the parameters, one by one. */
10189 i = TREE_VEC_LENGTH (expanded_args);
10192 /* We only partially substituted into the parameter
10193 pack. Our type is TYPE_PACK_EXPANSION. */
10194 type = expanded_args;
10195 expanded_args = NULL_TREE;
10203 type = TREE_VEC_ELT (expanded_args, i);
10205 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10207 if (type == error_mark_node)
10208 return error_mark_node;
10209 if (VOID_TYPE_P (type))
10211 if (complain & tf_error)
10213 error ("invalid parameter type %qT", type);
10215 error ("in declaration %q+D", in_decl);
10217 return error_mark_node;
10220 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10221 top-level qualifiers as required. */
10222 type = TYPE_MAIN_VARIANT (type_decays_to (type));
10224 /* We do not substitute into default arguments here. The standard
10225 mandates that they be instantiated only when needed, which is
10226 done in build_over_call. */
10227 default_arg = TREE_PURPOSE (arg_types);
10229 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10231 /* We've instantiated a template before its default arguments
10232 have been parsed. This can happen for a nested template
10233 class, and is not an error unless we require the default
10234 argument in a call of this function. */
10235 remaining_arg_types =
10236 tree_cons (default_arg, type, remaining_arg_types);
10237 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10238 remaining_arg_types);
10241 remaining_arg_types =
10242 hash_tree_cons (default_arg, type, remaining_arg_types);
10245 return remaining_arg_types;
10248 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10249 *not* handle the exception-specification for FNTYPE, because the
10250 initial substitution of explicitly provided template parameters
10251 during argument deduction forbids substitution into the
10252 exception-specification:
10256 All references in the function type of the function template to the
10257 corresponding template parameters are replaced by the specified tem-
10258 plate argument values. If a substitution in a template parameter or
10259 in the function type of the function template results in an invalid
10260 type, type deduction fails. [Note: The equivalent substitution in
10261 exception specifications is done only when the function is instanti-
10262 ated, at which point a program is ill-formed if the substitution
10263 results in an invalid type.] */
10266 tsubst_function_type (tree t,
10268 tsubst_flags_t complain,
10275 /* The TYPE_CONTEXT is not used for function/method types. */
10276 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10278 /* Substitute the return type. */
10279 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10280 if (return_type == error_mark_node)
10281 return error_mark_node;
10282 /* The standard does not presently indicate that creation of a
10283 function type with an invalid return type is a deduction failure.
10284 However, that is clearly analogous to creating an array of "void"
10285 or a reference to a reference. This is core issue #486. */
10286 if (TREE_CODE (return_type) == ARRAY_TYPE
10287 || TREE_CODE (return_type) == FUNCTION_TYPE)
10289 if (complain & tf_error)
10291 if (TREE_CODE (return_type) == ARRAY_TYPE)
10292 error ("function returning an array");
10294 error ("function returning a function");
10296 return error_mark_node;
10299 /* Substitute the argument types. */
10300 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10301 complain, in_decl);
10302 if (arg_types == error_mark_node)
10303 return error_mark_node;
10305 /* Construct a new type node and return it. */
10306 if (TREE_CODE (t) == FUNCTION_TYPE)
10308 fntype = build_function_type (return_type, arg_types);
10309 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10313 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10314 if (! MAYBE_CLASS_TYPE_P (r))
10318 Type deduction may fail for any of the following
10321 -- Attempting to create "pointer to member of T" when T
10322 is not a class type. */
10323 if (complain & tf_error)
10324 error ("creating pointer to member function of non-class type %qT",
10326 return error_mark_node;
10329 fntype = build_method_type_directly (r, return_type,
10330 TREE_CHAIN (arg_types));
10332 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10337 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10338 ARGS into that specification, and return the substituted
10339 specification. If there is no specification, return NULL_TREE. */
10342 tsubst_exception_specification (tree fntype,
10344 tsubst_flags_t complain,
10350 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10351 new_specs = NULL_TREE;
10352 if (specs && TREE_PURPOSE (specs))
10354 /* A noexcept-specifier. */
10355 new_specs = tsubst_copy_and_build
10356 (TREE_PURPOSE (specs), args, complain, in_decl, /*function_p=*/false,
10357 /*integral_constant_expression_p=*/true);
10358 new_specs = build_noexcept_spec (new_specs, complain);
10362 if (! TREE_VALUE (specs))
10369 tree expanded_specs = NULL_TREE;
10371 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10373 /* Expand the pack expansion type. */
10374 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10378 if (expanded_specs == error_mark_node)
10379 return error_mark_node;
10380 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10381 len = TREE_VEC_LENGTH (expanded_specs);
10384 /* We're substituting into a member template, so
10385 we got a TYPE_PACK_EXPANSION back. Add that
10386 expansion and move on. */
10387 gcc_assert (TREE_CODE (expanded_specs)
10388 == TYPE_PACK_EXPANSION);
10389 new_specs = add_exception_specifier (new_specs,
10392 specs = TREE_CHAIN (specs);
10397 for (i = 0; i < len; ++i)
10399 if (expanded_specs)
10400 spec = TREE_VEC_ELT (expanded_specs, i);
10402 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10403 if (spec == error_mark_node)
10405 new_specs = add_exception_specifier (new_specs, spec,
10409 specs = TREE_CHAIN (specs);
10415 /* Take the tree structure T and replace template parameters used
10416 therein with the argument vector ARGS. IN_DECL is an associated
10417 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10418 Issue error and warning messages under control of COMPLAIN. Note
10419 that we must be relatively non-tolerant of extensions here, in
10420 order to preserve conformance; if we allow substitutions that
10421 should not be allowed, we may allow argument deductions that should
10422 not succeed, and therefore report ambiguous overload situations
10423 where there are none. In theory, we could allow the substitution,
10424 but indicate that it should have failed, and allow our caller to
10425 make sure that the right thing happens, but we don't try to do this
10428 This function is used for dealing with types, decls and the like;
10429 for expressions, use tsubst_expr or tsubst_copy. */
10432 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10434 enum tree_code code;
10437 if (t == NULL_TREE || t == error_mark_node
10438 || t == integer_type_node
10439 || t == void_type_node
10440 || t == char_type_node
10441 || t == unknown_type_node
10442 || TREE_CODE (t) == NAMESPACE_DECL
10443 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10447 return tsubst_decl (t, args, complain);
10449 if (args == NULL_TREE)
10452 code = TREE_CODE (t);
10454 if (code == IDENTIFIER_NODE)
10455 type = IDENTIFIER_TYPE_VALUE (t);
10457 type = TREE_TYPE (t);
10459 gcc_assert (type != unknown_type_node);
10461 /* Reuse typedefs. We need to do this to handle dependent attributes,
10462 such as attribute aligned. */
10464 && typedef_variant_p (t))
10466 tree decl = TYPE_NAME (t);
10468 if (DECL_CLASS_SCOPE_P (decl)
10469 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10470 && uses_template_parms (DECL_CONTEXT (decl)))
10472 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10473 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10474 r = retrieve_specialization (tmpl, gen_args, 0);
10476 else if (DECL_FUNCTION_SCOPE_P (decl)
10477 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10478 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10479 r = retrieve_local_specialization (decl);
10481 /* The typedef is from a non-template context. */
10487 r = cp_build_qualified_type_real
10488 (r, cp_type_quals (t) | cp_type_quals (r),
10489 complain | tf_ignore_bad_quals);
10492 /* Else we must be instantiating the typedef, so fall through. */
10496 && code != TYPENAME_TYPE
10497 && code != TEMPLATE_TYPE_PARM
10498 && code != IDENTIFIER_NODE
10499 && code != FUNCTION_TYPE
10500 && code != METHOD_TYPE)
10501 type = tsubst (type, args, complain, in_decl);
10502 if (type == error_mark_node)
10503 return error_mark_node;
10509 case ENUMERAL_TYPE:
10510 return tsubst_aggr_type (t, args, complain, in_decl,
10511 /*entering_scope=*/0);
10514 case IDENTIFIER_NODE:
10525 if (t == integer_type_node)
10528 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10529 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10533 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10535 max = tsubst_expr (omax, args, complain, in_decl,
10536 /*integral_constant_expression_p=*/false);
10538 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10540 if (TREE_CODE (max) == NOP_EXPR
10541 && TREE_SIDE_EFFECTS (omax)
10542 && !TREE_TYPE (max))
10543 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10545 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10546 with TREE_SIDE_EFFECTS that indicates this is not an integral
10547 constant expression. */
10548 if (processing_template_decl
10549 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10551 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10552 TREE_SIDE_EFFECTS (max) = 1;
10555 return compute_array_index_type (NULL_TREE, max, complain);
10558 case TEMPLATE_TYPE_PARM:
10559 case TEMPLATE_TEMPLATE_PARM:
10560 case BOUND_TEMPLATE_TEMPLATE_PARM:
10561 case TEMPLATE_PARM_INDEX:
10566 tree arg = NULL_TREE;
10570 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10571 template_parm_level_and_index (t, &level, &idx);
10573 levels = TMPL_ARGS_DEPTH (args);
10574 if (level <= levels)
10576 arg = TMPL_ARG (args, level, idx);
10578 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10579 /* See through ARGUMENT_PACK_SELECT arguments. */
10580 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10583 if (arg == error_mark_node)
10584 return error_mark_node;
10585 else if (arg != NULL_TREE)
10587 if (ARGUMENT_PACK_P (arg))
10588 /* If ARG is an argument pack, we don't actually want to
10589 perform a substitution here, because substitutions
10590 for argument packs are only done
10591 element-by-element. We can get to this point when
10592 substituting the type of a non-type template
10593 parameter pack, when that type actually contains
10594 template parameter packs from an outer template, e.g.,
10596 template<typename... Types> struct A {
10597 template<Types... Values> struct B { };
10601 if (code == TEMPLATE_TYPE_PARM)
10604 gcc_assert (TYPE_P (arg));
10606 quals = cp_type_quals (arg) | cp_type_quals (t);
10608 return cp_build_qualified_type_real
10609 (arg, quals, complain | tf_ignore_bad_quals);
10611 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10613 /* We are processing a type constructed from a
10614 template template parameter. */
10615 tree argvec = tsubst (TYPE_TI_ARGS (t),
10616 args, complain, in_decl);
10617 if (argvec == error_mark_node)
10618 return error_mark_node;
10620 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10621 are resolving nested-types in the signature of a
10622 member function templates. Otherwise ARG is a
10623 TEMPLATE_DECL and is the real template to be
10625 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10626 arg = TYPE_NAME (arg);
10628 r = lookup_template_class (arg,
10630 DECL_CONTEXT (arg),
10631 /*entering_scope=*/0,
10633 return cp_build_qualified_type_real
10634 (r, cp_type_quals (t), complain);
10637 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10638 return unshare_expr (arg);
10642 /* This can happen during the attempted tsubst'ing in
10643 unify. This means that we don't yet have any information
10644 about the template parameter in question. */
10647 /* If we get here, we must have been looking at a parm for a
10648 more deeply nested template. Make a new version of this
10649 template parameter, but with a lower level. */
10652 case TEMPLATE_TYPE_PARM:
10653 case TEMPLATE_TEMPLATE_PARM:
10654 case BOUND_TEMPLATE_TEMPLATE_PARM:
10655 if (cp_type_quals (t))
10657 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10658 r = cp_build_qualified_type_real
10659 (r, cp_type_quals (t),
10660 complain | (code == TEMPLATE_TYPE_PARM
10661 ? tf_ignore_bad_quals : 0));
10666 TEMPLATE_TYPE_PARM_INDEX (r)
10667 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10668 r, levels, args, complain);
10669 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10670 TYPE_MAIN_VARIANT (r) = r;
10671 TYPE_POINTER_TO (r) = NULL_TREE;
10672 TYPE_REFERENCE_TO (r) = NULL_TREE;
10674 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10675 /* We have reduced the level of the template
10676 template parameter, but not the levels of its
10677 template parameters, so canonical_type_parameter
10678 will not be able to find the canonical template
10679 template parameter for this level. Thus, we
10680 require structural equality checking to compare
10681 TEMPLATE_TEMPLATE_PARMs. */
10682 SET_TYPE_STRUCTURAL_EQUALITY (r);
10683 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10684 SET_TYPE_STRUCTURAL_EQUALITY (r);
10686 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10688 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10690 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10691 complain, in_decl);
10692 if (argvec == error_mark_node)
10693 return error_mark_node;
10695 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10696 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10701 case TEMPLATE_PARM_INDEX:
10702 r = reduce_template_parm_level (t, type, levels, args, complain);
10706 gcc_unreachable ();
10714 tree purpose, value, chain;
10716 if (t == void_list_node)
10719 purpose = TREE_PURPOSE (t);
10722 purpose = tsubst (purpose, args, complain, in_decl);
10723 if (purpose == error_mark_node)
10724 return error_mark_node;
10726 value = TREE_VALUE (t);
10729 value = tsubst (value, args, complain, in_decl);
10730 if (value == error_mark_node)
10731 return error_mark_node;
10733 chain = TREE_CHAIN (t);
10734 if (chain && chain != void_type_node)
10736 chain = tsubst (chain, args, complain, in_decl);
10737 if (chain == error_mark_node)
10738 return error_mark_node;
10740 if (purpose == TREE_PURPOSE (t)
10741 && value == TREE_VALUE (t)
10742 && chain == TREE_CHAIN (t))
10744 return hash_tree_cons (purpose, value, chain);
10748 /* We should never be tsubsting a binfo. */
10749 gcc_unreachable ();
10752 /* A vector of template arguments. */
10753 gcc_assert (!type);
10754 return tsubst_template_args (t, args, complain, in_decl);
10757 case REFERENCE_TYPE:
10759 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10764 Type deduction may fail for any of the following
10767 -- Attempting to create a pointer to reference type.
10768 -- Attempting to create a reference to a reference type or
10769 a reference to void.
10771 Core issue 106 says that creating a reference to a reference
10772 during instantiation is no longer a cause for failure. We
10773 only enforce this check in strict C++98 mode. */
10774 if ((TREE_CODE (type) == REFERENCE_TYPE
10775 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10776 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10778 static location_t last_loc;
10780 /* We keep track of the last time we issued this error
10781 message to avoid spewing a ton of messages during a
10782 single bad template instantiation. */
10783 if (complain & tf_error
10784 && last_loc != input_location)
10786 if (TREE_CODE (type) == VOID_TYPE)
10787 error ("forming reference to void");
10788 else if (code == POINTER_TYPE)
10789 error ("forming pointer to reference type %qT", type);
10791 error ("forming reference to reference type %qT", type);
10792 last_loc = input_location;
10795 return error_mark_node;
10797 else if (code == POINTER_TYPE)
10799 r = build_pointer_type (type);
10800 if (TREE_CODE (type) == METHOD_TYPE)
10801 r = build_ptrmemfunc_type (r);
10803 else if (TREE_CODE (type) == REFERENCE_TYPE)
10804 /* In C++0x, during template argument substitution, when there is an
10805 attempt to create a reference to a reference type, reference
10806 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10808 "If a template-argument for a template-parameter T names a type
10809 that is a reference to a type A, an attempt to create the type
10810 'lvalue reference to cv T' creates the type 'lvalue reference to
10811 A,' while an attempt to create the type type rvalue reference to
10812 cv T' creates the type T"
10814 r = cp_build_reference_type
10816 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10818 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10819 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10821 if (r != error_mark_node)
10822 /* Will this ever be needed for TYPE_..._TO values? */
10829 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10830 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10834 Type deduction may fail for any of the following
10837 -- Attempting to create "pointer to member of T" when T
10838 is not a class type. */
10839 if (complain & tf_error)
10840 error ("creating pointer to member of non-class type %qT", r);
10841 return error_mark_node;
10843 if (TREE_CODE (type) == REFERENCE_TYPE)
10845 if (complain & tf_error)
10846 error ("creating pointer to member reference type %qT", type);
10847 return error_mark_node;
10849 if (TREE_CODE (type) == VOID_TYPE)
10851 if (complain & tf_error)
10852 error ("creating pointer to member of type void");
10853 return error_mark_node;
10855 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10856 if (TREE_CODE (type) == FUNCTION_TYPE)
10858 /* The type of the implicit object parameter gets its
10859 cv-qualifiers from the FUNCTION_TYPE. */
10861 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10862 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10863 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10867 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10871 case FUNCTION_TYPE:
10876 fntype = tsubst_function_type (t, args, complain, in_decl);
10877 if (fntype == error_mark_node)
10878 return error_mark_node;
10880 /* Substitute the exception specification. */
10881 specs = tsubst_exception_specification (t, args, complain,
10883 if (specs == error_mark_node)
10884 return error_mark_node;
10886 fntype = build_exception_variant (fntype, specs);
10891 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10892 if (domain == error_mark_node)
10893 return error_mark_node;
10895 /* As an optimization, we avoid regenerating the array type if
10896 it will obviously be the same as T. */
10897 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10900 /* These checks should match the ones in grokdeclarator.
10904 The deduction may fail for any of the following reasons:
10906 -- Attempting to create an array with an element type that
10907 is void, a function type, or a reference type, or [DR337]
10908 an abstract class type. */
10909 if (TREE_CODE (type) == VOID_TYPE
10910 || TREE_CODE (type) == FUNCTION_TYPE
10911 || TREE_CODE (type) == REFERENCE_TYPE)
10913 if (complain & tf_error)
10914 error ("creating array of %qT", type);
10915 return error_mark_node;
10917 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10919 if (complain & tf_error)
10920 error ("creating array of %qT, which is an abstract class type",
10922 return error_mark_node;
10925 r = build_cplus_array_type (type, domain);
10927 if (TYPE_USER_ALIGN (t))
10929 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10930 TYPE_USER_ALIGN (r) = 1;
10936 case TYPENAME_TYPE:
10938 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10939 in_decl, /*entering_scope=*/1);
10940 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10941 complain, in_decl);
10943 if (ctx == error_mark_node || f == error_mark_node)
10944 return error_mark_node;
10946 if (!MAYBE_CLASS_TYPE_P (ctx))
10948 if (complain & tf_error)
10949 error ("%qT is not a class, struct, or union type", ctx);
10950 return error_mark_node;
10952 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10954 /* Normally, make_typename_type does not require that the CTX
10955 have complete type in order to allow things like:
10957 template <class T> struct S { typename S<T>::X Y; };
10959 But, such constructs have already been resolved by this
10960 point, so here CTX really should have complete type, unless
10961 it's a partial instantiation. */
10962 ctx = complete_type (ctx);
10963 if (!COMPLETE_TYPE_P (ctx))
10965 if (complain & tf_error)
10966 cxx_incomplete_type_error (NULL_TREE, ctx);
10967 return error_mark_node;
10971 f = make_typename_type (ctx, f, typename_type,
10972 (complain & tf_error) | tf_keep_type_decl);
10973 if (f == error_mark_node)
10975 if (TREE_CODE (f) == TYPE_DECL)
10977 complain |= tf_ignore_bad_quals;
10981 if (TREE_CODE (f) != TYPENAME_TYPE)
10983 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10985 if (complain & tf_error)
10986 error ("%qT resolves to %qT, which is not an enumeration type",
10989 return error_mark_node;
10991 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10993 if (complain & tf_error)
10994 error ("%qT resolves to %qT, which is is not a class type",
10997 return error_mark_node;
11001 return cp_build_qualified_type_real
11002 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11005 case UNBOUND_CLASS_TEMPLATE:
11007 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11008 in_decl, /*entering_scope=*/1);
11009 tree name = TYPE_IDENTIFIER (t);
11010 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11012 if (ctx == error_mark_node || name == error_mark_node)
11013 return error_mark_node;
11016 parm_list = tsubst_template_parms (parm_list, args, complain);
11017 return make_unbound_class_template (ctx, name, parm_list, complain);
11024 ++cp_unevaluated_operand;
11025 ++c_inhibit_evaluation_warnings;
11027 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11029 /*integral_constant_expression_p=*/false);
11031 --cp_unevaluated_operand;
11032 --c_inhibit_evaluation_warnings;
11034 type = finish_typeof (type);
11035 return cp_build_qualified_type_real (type,
11037 | cp_type_quals (type),
11041 case DECLTYPE_TYPE:
11045 ++cp_unevaluated_operand;
11046 ++c_inhibit_evaluation_warnings;
11048 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11050 /*integral_constant_expression_p=*/false);
11052 --cp_unevaluated_operand;
11053 --c_inhibit_evaluation_warnings;
11055 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11056 type = lambda_capture_field_type (type);
11057 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
11058 type = lambda_return_type (type);
11060 type = finish_decltype_type
11061 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11062 return cp_build_qualified_type_real (type,
11064 | cp_type_quals (type),
11068 case UNDERLYING_TYPE:
11070 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11071 complain, in_decl);
11072 return finish_underlying_type (type);
11075 case TYPE_ARGUMENT_PACK:
11076 case NONTYPE_ARGUMENT_PACK:
11078 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11080 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11084 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11086 /* For template nontype argument packs, also substitute into
11088 if (code == NONTYPE_ARGUMENT_PACK)
11089 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11107 /* We should use one of the expression tsubsts for these codes. */
11108 gcc_unreachable ();
11111 sorry ("use of %qs in template", tree_code_name [(int) code]);
11112 return error_mark_node;
11116 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11117 type of the expression on the left-hand side of the "." or "->"
11121 tsubst_baselink (tree baselink, tree object_type,
11122 tree args, tsubst_flags_t complain, tree in_decl)
11125 tree qualifying_scope;
11128 tree template_args = 0;
11129 bool template_id_p = false;
11131 /* A baselink indicates a function from a base class. Both the
11132 BASELINK_ACCESS_BINFO and the base class referenced may
11133 indicate bases of the template class, rather than the
11134 instantiated class. In addition, lookups that were not
11135 ambiguous before may be ambiguous now. Therefore, we perform
11136 the lookup again. */
11137 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11138 qualifying_scope = tsubst (qualifying_scope, args,
11139 complain, in_decl);
11140 fns = BASELINK_FUNCTIONS (baselink);
11141 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11142 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11144 template_id_p = true;
11145 template_args = TREE_OPERAND (fns, 1);
11146 fns = TREE_OPERAND (fns, 0);
11148 template_args = tsubst_template_args (template_args, args,
11149 complain, in_decl);
11151 name = DECL_NAME (get_first_fn (fns));
11152 if (IDENTIFIER_TYPENAME_P (name))
11153 name = mangle_conv_op_name_for_type (optype);
11154 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11156 return error_mark_node;
11158 /* If lookup found a single function, mark it as used at this
11159 point. (If it lookup found multiple functions the one selected
11160 later by overload resolution will be marked as used at that
11162 if (BASELINK_P (baselink))
11163 fns = BASELINK_FUNCTIONS (baselink);
11164 if (!template_id_p && !really_overloaded_fn (fns))
11165 mark_used (OVL_CURRENT (fns));
11167 /* Add back the template arguments, if present. */
11168 if (BASELINK_P (baselink) && template_id_p)
11169 BASELINK_FUNCTIONS (baselink)
11170 = build_nt (TEMPLATE_ID_EXPR,
11171 BASELINK_FUNCTIONS (baselink),
11173 /* Update the conversion operator type. */
11174 BASELINK_OPTYPE (baselink) = optype;
11177 object_type = current_class_type;
11178 return adjust_result_of_qualified_name_lookup (baselink,
11183 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11184 true if the qualified-id will be a postfix-expression in-and-of
11185 itself; false if more of the postfix-expression follows the
11186 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11190 tsubst_qualified_id (tree qualified_id, tree args,
11191 tsubst_flags_t complain, tree in_decl,
11192 bool done, bool address_p)
11198 tree template_args;
11200 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11202 /* Figure out what name to look up. */
11203 name = TREE_OPERAND (qualified_id, 1);
11204 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11206 is_template = true;
11207 template_args = TREE_OPERAND (name, 1);
11209 template_args = tsubst_template_args (template_args, args,
11210 complain, in_decl);
11211 name = TREE_OPERAND (name, 0);
11215 is_template = false;
11216 template_args = NULL_TREE;
11219 /* Substitute into the qualifying scope. When there are no ARGS, we
11220 are just trying to simplify a non-dependent expression. In that
11221 case the qualifying scope may be dependent, and, in any case,
11222 substituting will not help. */
11223 scope = TREE_OPERAND (qualified_id, 0);
11226 scope = tsubst (scope, args, complain, in_decl);
11227 expr = tsubst_copy (name, args, complain, in_decl);
11232 if (dependent_scope_p (scope))
11233 return build_qualified_name (NULL_TREE, scope, expr,
11234 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11236 if (!BASELINK_P (name) && !DECL_P (expr))
11238 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11240 /* A BIT_NOT_EXPR is used to represent a destructor. */
11241 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11243 error ("qualifying type %qT does not match destructor name ~%qT",
11244 scope, TREE_OPERAND (expr, 0));
11245 expr = error_mark_node;
11248 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11249 /*is_type_p=*/0, false);
11252 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11253 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11254 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11256 if (complain & tf_error)
11258 error ("dependent-name %qE is parsed as a non-type, but "
11259 "instantiation yields a type", qualified_id);
11260 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11262 return error_mark_node;
11268 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11270 /* Remember that there was a reference to this entity. */
11274 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11276 if (complain & tf_error)
11277 qualified_name_lookup_error (scope,
11278 TREE_OPERAND (qualified_id, 1),
11279 expr, input_location);
11280 return error_mark_node;
11284 expr = lookup_template_function (expr, template_args);
11286 if (expr == error_mark_node && complain & tf_error)
11287 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11288 expr, input_location);
11289 else if (TYPE_P (scope))
11291 expr = (adjust_result_of_qualified_name_lookup
11292 (expr, scope, current_class_type));
11293 expr = (finish_qualified_id_expr
11294 (scope, expr, done, address_p,
11295 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11296 /*template_arg_p=*/false));
11299 /* Expressions do not generally have reference type. */
11300 if (TREE_CODE (expr) != SCOPE_REF
11301 /* However, if we're about to form a pointer-to-member, we just
11302 want the referenced member referenced. */
11303 && TREE_CODE (expr) != OFFSET_REF)
11304 expr = convert_from_reference (expr);
11309 /* Like tsubst, but deals with expressions. This function just replaces
11310 template parms; to finish processing the resultant expression, use
11314 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11316 enum tree_code code;
11319 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11322 code = TREE_CODE (t);
11327 r = retrieve_local_specialization (t);
11332 /* This can happen for a parameter name used later in a function
11333 declaration (such as in a late-specified return type). Just
11334 make a dummy decl, since it's only used for its type. */
11335 gcc_assert (cp_unevaluated_operand != 0);
11336 /* We copy T because want to tsubst the PARM_DECL only,
11337 not the following PARM_DECLs that are chained to T. */
11339 r = tsubst_decl (c, args, complain);
11340 /* Give it the template pattern as its context; its true context
11341 hasn't been instantiated yet and this is good enough for
11343 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11346 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11347 r = ARGUMENT_PACK_SELECT_ARG (r);
11356 if (DECL_TEMPLATE_PARM_P (t))
11357 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11358 /* There is no need to substitute into namespace-scope
11360 if (DECL_NAMESPACE_SCOPE_P (t))
11362 /* If ARGS is NULL, then T is known to be non-dependent. */
11363 if (args == NULL_TREE)
11364 return integral_constant_value (t);
11366 /* Unfortunately, we cannot just call lookup_name here.
11369 template <int I> int f() {
11371 struct S { void g() { E e = a; } };
11374 When we instantiate f<7>::S::g(), say, lookup_name is not
11375 clever enough to find f<7>::a. */
11377 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11378 /*entering_scope=*/0);
11380 for (v = TYPE_VALUES (enum_type);
11382 v = TREE_CHAIN (v))
11383 if (TREE_PURPOSE (v) == DECL_NAME (t))
11384 return TREE_VALUE (v);
11386 /* We didn't find the name. That should never happen; if
11387 name-lookup found it during preliminary parsing, we
11388 should find it again here during instantiation. */
11389 gcc_unreachable ();
11394 if (DECL_CONTEXT (t))
11398 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11399 /*entering_scope=*/1);
11400 if (ctx != DECL_CONTEXT (t))
11402 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11405 if (complain & tf_error)
11406 error ("using invalid field %qD", t);
11407 return error_mark_node;
11416 case FUNCTION_DECL:
11417 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11418 || local_variable_p (t))
11419 t = tsubst (t, args, complain, in_decl);
11424 /* An OVERLOAD will always be a non-dependent overload set; an
11425 overload set from function scope will just be represented with an
11426 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11427 gcc_assert (!uses_template_parms (t));
11431 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11433 case TEMPLATE_DECL:
11434 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11435 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11436 args, complain, in_decl);
11437 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11438 return tsubst (t, args, complain, in_decl);
11439 else if (DECL_CLASS_SCOPE_P (t)
11440 && uses_template_parms (DECL_CONTEXT (t)))
11442 /* Template template argument like the following example need
11445 template <template <class> class TT> struct C {};
11446 template <class T> struct D {
11447 template <class U> struct E {};
11452 We are processing the template argument `E' in #1 for
11453 the template instantiation #2. Originally, `E' is a
11454 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11455 have to substitute this with one having context `D<int>'. */
11457 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11458 return lookup_field (context, DECL_NAME(t), 0, false);
11461 /* Ordinary template template argument. */
11465 case REINTERPRET_CAST_EXPR:
11466 case CONST_CAST_EXPR:
11467 case STATIC_CAST_EXPR:
11468 case DYNAMIC_CAST_EXPR:
11471 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11472 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11475 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11481 ++cp_unevaluated_operand;
11482 ++c_inhibit_evaluation_warnings;
11483 /* We only want to compute the number of arguments. */
11484 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11485 complain, in_decl);
11486 --cp_unevaluated_operand;
11487 --c_inhibit_evaluation_warnings;
11489 if (TREE_CODE (expanded) == TREE_VEC)
11490 len = TREE_VEC_LENGTH (expanded);
11492 if (expanded == error_mark_node)
11493 return error_mark_node;
11494 else if (PACK_EXPANSION_P (expanded)
11495 || (TREE_CODE (expanded) == TREE_VEC
11497 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11499 if (TREE_CODE (expanded) == TREE_VEC)
11500 expanded = TREE_VEC_ELT (expanded, len - 1);
11502 if (TYPE_P (expanded))
11503 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11504 complain & tf_error);
11506 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11507 complain & tf_error);
11510 return build_int_cst (size_type_node, len);
11516 case TRUTH_NOT_EXPR:
11519 case UNARY_PLUS_EXPR: /* Unary + */
11521 case AT_ENCODE_EXPR:
11525 case REALPART_EXPR:
11526 case IMAGPART_EXPR:
11528 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11529 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11531 case COMPONENT_REF:
11536 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11537 name = TREE_OPERAND (t, 1);
11538 if (TREE_CODE (name) == BIT_NOT_EXPR)
11540 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11541 complain, in_decl);
11542 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11544 else if (TREE_CODE (name) == SCOPE_REF
11545 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11547 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11548 complain, in_decl);
11549 name = TREE_OPERAND (name, 1);
11550 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11551 complain, in_decl);
11552 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11553 name = build_qualified_name (/*type=*/NULL_TREE,
11555 /*template_p=*/false);
11557 else if (TREE_CODE (name) == BASELINK)
11558 name = tsubst_baselink (name,
11559 non_reference (TREE_TYPE (object)),
11563 name = tsubst_copy (name, args, complain, in_decl);
11564 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11570 case TRUNC_DIV_EXPR:
11571 case CEIL_DIV_EXPR:
11572 case FLOOR_DIV_EXPR:
11573 case ROUND_DIV_EXPR:
11574 case EXACT_DIV_EXPR:
11578 case TRUNC_MOD_EXPR:
11579 case FLOOR_MOD_EXPR:
11580 case TRUTH_ANDIF_EXPR:
11581 case TRUTH_ORIF_EXPR:
11582 case TRUTH_AND_EXPR:
11583 case TRUTH_OR_EXPR:
11596 case COMPOUND_EXPR:
11599 case PREDECREMENT_EXPR:
11600 case PREINCREMENT_EXPR:
11601 case POSTDECREMENT_EXPR:
11602 case POSTINCREMENT_EXPR:
11604 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11605 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11608 return build_qualified_name (/*type=*/NULL_TREE,
11609 tsubst_copy (TREE_OPERAND (t, 0),
11610 args, complain, in_decl),
11611 tsubst_copy (TREE_OPERAND (t, 1),
11612 args, complain, in_decl),
11613 QUALIFIED_NAME_IS_TEMPLATE (t));
11618 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11619 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11620 NULL_TREE, NULL_TREE);
11624 int n = VL_EXP_OPERAND_LENGTH (t);
11625 tree result = build_vl_exp (CALL_EXPR, n);
11627 for (i = 0; i < n; i++)
11628 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11629 complain, in_decl);
11635 case PSEUDO_DTOR_EXPR:
11638 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11639 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11640 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11641 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11648 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11649 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11650 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11651 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11658 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11659 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11660 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11661 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11665 case TEMPLATE_ID_EXPR:
11667 /* Substituted template arguments */
11668 tree fn = TREE_OPERAND (t, 0);
11669 tree targs = TREE_OPERAND (t, 1);
11671 fn = tsubst_copy (fn, args, complain, in_decl);
11673 targs = tsubst_template_args (targs, args, complain, in_decl);
11675 return lookup_template_function (fn, targs);
11680 tree purpose, value, chain;
11682 if (t == void_list_node)
11685 purpose = TREE_PURPOSE (t);
11687 purpose = tsubst_copy (purpose, args, complain, in_decl);
11688 value = TREE_VALUE (t);
11690 value = tsubst_copy (value, args, complain, in_decl);
11691 chain = TREE_CHAIN (t);
11692 if (chain && chain != void_type_node)
11693 chain = tsubst_copy (chain, args, complain, in_decl);
11694 if (purpose == TREE_PURPOSE (t)
11695 && value == TREE_VALUE (t)
11696 && chain == TREE_CHAIN (t))
11698 return tree_cons (purpose, value, chain);
11703 case ENUMERAL_TYPE:
11705 case TEMPLATE_TYPE_PARM:
11706 case TEMPLATE_TEMPLATE_PARM:
11707 case BOUND_TEMPLATE_TEMPLATE_PARM:
11708 case TEMPLATE_PARM_INDEX:
11710 case REFERENCE_TYPE:
11712 case FUNCTION_TYPE:
11715 case TYPENAME_TYPE:
11716 case UNBOUND_CLASS_TEMPLATE:
11718 case DECLTYPE_TYPE:
11720 return tsubst (t, args, complain, in_decl);
11722 case IDENTIFIER_NODE:
11723 if (IDENTIFIER_TYPENAME_P (t))
11725 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11726 return mangle_conv_op_name_for_type (new_type);
11732 /* This is handled by tsubst_copy_and_build. */
11733 gcc_unreachable ();
11736 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11738 tsubst (TREE_TYPE (t), args, complain, in_decl));
11740 case CLEANUP_POINT_EXPR:
11741 /* We shouldn't have built any of these during initial template
11742 generation. Instead, they should be built during instantiation
11743 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11744 gcc_unreachable ();
11748 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11749 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11750 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11751 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11752 mark_used (TREE_OPERAND (r, 1));
11755 case EXPR_PACK_EXPANSION:
11756 error ("invalid use of pack expansion expression");
11757 return error_mark_node;
11759 case NONTYPE_ARGUMENT_PACK:
11760 error ("use %<...%> to expand argument pack");
11761 return error_mark_node;
11768 /* Instantiate any typedefs in the type. */
11769 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11770 r = fold_convert (type, t);
11771 gcc_assert (TREE_CODE (r) == code);
11776 /* These can sometimes show up in a partial instantiation, but never
11777 involve template parms. */
11778 gcc_assert (!uses_template_parms (t));
11782 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
11783 gcc_checking_assert (false);
11788 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11791 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11794 tree new_clauses = NULL, nc, oc;
11796 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11798 nc = copy_node (oc);
11799 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11802 switch (OMP_CLAUSE_CODE (nc))
11804 case OMP_CLAUSE_LASTPRIVATE:
11805 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11807 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11808 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11809 in_decl, /*integral_constant_expression_p=*/false);
11810 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11811 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11814 case OMP_CLAUSE_PRIVATE:
11815 case OMP_CLAUSE_SHARED:
11816 case OMP_CLAUSE_FIRSTPRIVATE:
11817 case OMP_CLAUSE_REDUCTION:
11818 case OMP_CLAUSE_COPYIN:
11819 case OMP_CLAUSE_COPYPRIVATE:
11820 case OMP_CLAUSE_IF:
11821 case OMP_CLAUSE_NUM_THREADS:
11822 case OMP_CLAUSE_SCHEDULE:
11823 case OMP_CLAUSE_COLLAPSE:
11824 OMP_CLAUSE_OPERAND (nc, 0)
11825 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11826 in_decl, /*integral_constant_expression_p=*/false);
11828 case OMP_CLAUSE_NOWAIT:
11829 case OMP_CLAUSE_ORDERED:
11830 case OMP_CLAUSE_DEFAULT:
11831 case OMP_CLAUSE_UNTIED:
11834 gcc_unreachable ();
11838 return finish_omp_clauses (nreverse (new_clauses));
11841 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11844 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11847 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11849 tree purpose, value, chain;
11854 if (TREE_CODE (t) != TREE_LIST)
11855 return tsubst_copy_and_build (t, args, complain, in_decl,
11856 /*function_p=*/false,
11857 /*integral_constant_expression_p=*/false);
11859 if (t == void_list_node)
11862 purpose = TREE_PURPOSE (t);
11864 purpose = RECUR (purpose);
11865 value = TREE_VALUE (t);
11866 if (value && TREE_CODE (value) != LABEL_DECL)
11867 value = RECUR (value);
11868 chain = TREE_CHAIN (t);
11869 if (chain && chain != void_type_node)
11870 chain = RECUR (chain);
11871 return tree_cons (purpose, value, chain);
11875 /* Substitute one OMP_FOR iterator. */
11878 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11879 tree condv, tree incrv, tree *clauses,
11880 tree args, tsubst_flags_t complain, tree in_decl,
11881 bool integral_constant_expression_p)
11883 #define RECUR(NODE) \
11884 tsubst_expr ((NODE), args, complain, in_decl, \
11885 integral_constant_expression_p)
11886 tree decl, init, cond, incr, auto_node;
11888 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11889 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11890 decl = RECUR (TREE_OPERAND (init, 0));
11891 init = TREE_OPERAND (init, 1);
11892 auto_node = type_uses_auto (TREE_TYPE (decl));
11893 if (auto_node && init)
11895 tree init_expr = init;
11896 if (TREE_CODE (init_expr) == DECL_EXPR)
11897 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11898 init_expr = RECUR (init_expr);
11900 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11902 gcc_assert (!type_dependent_expression_p (decl));
11904 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11906 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11907 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11908 if (TREE_CODE (incr) == MODIFY_EXPR)
11909 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11910 RECUR (TREE_OPERAND (incr, 1)),
11913 incr = RECUR (incr);
11914 TREE_VEC_ELT (declv, i) = decl;
11915 TREE_VEC_ELT (initv, i) = init;
11916 TREE_VEC_ELT (condv, i) = cond;
11917 TREE_VEC_ELT (incrv, i) = incr;
11921 if (init && TREE_CODE (init) != DECL_EXPR)
11924 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11926 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11927 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11928 && OMP_CLAUSE_DECL (c) == decl)
11930 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11931 && OMP_CLAUSE_DECL (c) == decl)
11932 error ("iteration variable %qD should not be firstprivate", decl);
11933 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11934 && OMP_CLAUSE_DECL (c) == decl)
11935 error ("iteration variable %qD should not be reduction", decl);
11939 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11940 OMP_CLAUSE_DECL (c) = decl;
11941 c = finish_omp_clauses (c);
11944 OMP_CLAUSE_CHAIN (c) = *clauses;
11949 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11950 if (COMPARISON_CLASS_P (cond))
11951 cond = build2 (TREE_CODE (cond), boolean_type_node,
11952 RECUR (TREE_OPERAND (cond, 0)),
11953 RECUR (TREE_OPERAND (cond, 1)));
11955 cond = RECUR (cond);
11956 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11957 switch (TREE_CODE (incr))
11959 case PREINCREMENT_EXPR:
11960 case PREDECREMENT_EXPR:
11961 case POSTINCREMENT_EXPR:
11962 case POSTDECREMENT_EXPR:
11963 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11964 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11967 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11968 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11970 tree rhs = TREE_OPERAND (incr, 1);
11971 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11972 RECUR (TREE_OPERAND (incr, 0)),
11973 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11974 RECUR (TREE_OPERAND (rhs, 0)),
11975 RECUR (TREE_OPERAND (rhs, 1))));
11978 incr = RECUR (incr);
11981 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11982 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11984 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11985 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11986 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11987 TREE_TYPE (decl), lhs,
11988 RECUR (TREE_OPERAND (incr, 2))));
11990 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11991 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11992 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11994 tree rhs = TREE_OPERAND (incr, 2);
11995 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11996 RECUR (TREE_OPERAND (incr, 0)),
11997 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11998 RECUR (TREE_OPERAND (rhs, 0)),
11999 RECUR (TREE_OPERAND (rhs, 1))));
12002 incr = RECUR (incr);
12005 incr = RECUR (incr);
12009 TREE_VEC_ELT (declv, i) = decl;
12010 TREE_VEC_ELT (initv, i) = init;
12011 TREE_VEC_ELT (condv, i) = cond;
12012 TREE_VEC_ELT (incrv, i) = incr;
12016 /* Like tsubst_copy for expressions, etc. but also does semantic
12020 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12021 bool integral_constant_expression_p)
12023 #define RECUR(NODE) \
12024 tsubst_expr ((NODE), args, complain, in_decl, \
12025 integral_constant_expression_p)
12029 if (t == NULL_TREE || t == error_mark_node)
12032 if (EXPR_HAS_LOCATION (t))
12033 input_location = EXPR_LOCATION (t);
12034 if (STATEMENT_CODE_P (TREE_CODE (t)))
12035 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12037 switch (TREE_CODE (t))
12039 case STATEMENT_LIST:
12041 tree_stmt_iterator i;
12042 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12043 RECUR (tsi_stmt (i));
12047 case CTOR_INITIALIZER:
12048 finish_mem_initializers (tsubst_initializer_list
12049 (TREE_OPERAND (t, 0), args));
12053 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12057 tmp = RECUR (EXPR_STMT_EXPR (t));
12058 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12059 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12061 finish_expr_stmt (tmp);
12065 do_using_directive (USING_STMT_NAMESPACE (t));
12070 tree decl, pattern_decl;
12073 pattern_decl = decl = DECL_EXPR_DECL (t);
12074 if (TREE_CODE (decl) == LABEL_DECL)
12075 finish_label_decl (DECL_NAME (decl));
12076 else if (TREE_CODE (decl) == USING_DECL)
12078 tree scope = USING_DECL_SCOPE (decl);
12079 tree name = DECL_NAME (decl);
12082 scope = tsubst (scope, args, complain, in_decl);
12083 decl = lookup_qualified_name (scope, name,
12084 /*is_type_p=*/false,
12085 /*complain=*/false);
12086 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12087 qualified_name_lookup_error (scope, name, decl, input_location);
12089 do_local_using_decl (decl, scope, name);
12093 init = DECL_INITIAL (decl);
12094 decl = tsubst (decl, args, complain, in_decl);
12095 if (decl != error_mark_node)
12097 /* By marking the declaration as instantiated, we avoid
12098 trying to instantiate it. Since instantiate_decl can't
12099 handle local variables, and since we've already done
12100 all that needs to be done, that's the right thing to
12102 if (TREE_CODE (decl) == VAR_DECL)
12103 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12104 if (TREE_CODE (decl) == VAR_DECL
12105 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12106 /* Anonymous aggregates are a special case. */
12107 finish_anon_union (decl);
12110 int const_init = false;
12111 maybe_push_decl (decl);
12112 if (TREE_CODE (decl) == VAR_DECL
12113 && DECL_PRETTY_FUNCTION_P (decl))
12115 /* For __PRETTY_FUNCTION__ we have to adjust the
12117 const char *const name
12118 = cxx_printable_name (current_function_decl, 2);
12119 init = cp_fname_init (name, &TREE_TYPE (decl));
12123 tree t = RECUR (init);
12127 /* If we had an initializer but it
12128 instantiated to nothing,
12129 value-initialize the object. This will
12130 only occur when the initializer was a
12131 pack expansion where the parameter packs
12132 used in that expansion were of length
12134 init = build_value_init (TREE_TYPE (decl),
12136 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12137 init = get_target_expr_sfinae (init, complain);
12143 if (TREE_CODE (decl) == VAR_DECL)
12144 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12146 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12151 /* A DECL_EXPR can also be used as an expression, in the condition
12152 clause of an if/for/while construct. */
12157 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12158 RECUR (FOR_INIT_STMT (t));
12159 finish_for_init_stmt (stmt);
12160 tmp = RECUR (FOR_COND (t));
12161 finish_for_cond (tmp, stmt);
12162 tmp = RECUR (FOR_EXPR (t));
12163 finish_for_expr (tmp, stmt);
12164 RECUR (FOR_BODY (t));
12165 finish_for_stmt (stmt);
12168 case RANGE_FOR_STMT:
12171 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12172 decl = RANGE_FOR_DECL (t);
12173 decl = tsubst (decl, args, complain, in_decl);
12174 maybe_push_decl (decl);
12175 expr = RECUR (RANGE_FOR_EXPR (t));
12176 stmt = cp_convert_range_for (stmt, decl, expr);
12177 RECUR (RANGE_FOR_BODY (t));
12178 finish_for_stmt (stmt);
12183 stmt = begin_while_stmt ();
12184 tmp = RECUR (WHILE_COND (t));
12185 finish_while_stmt_cond (tmp, stmt);
12186 RECUR (WHILE_BODY (t));
12187 finish_while_stmt (stmt);
12191 stmt = begin_do_stmt ();
12192 RECUR (DO_BODY (t));
12193 finish_do_body (stmt);
12194 tmp = RECUR (DO_COND (t));
12195 finish_do_stmt (tmp, stmt);
12199 stmt = begin_if_stmt ();
12200 tmp = RECUR (IF_COND (t));
12201 finish_if_stmt_cond (tmp, stmt);
12202 RECUR (THEN_CLAUSE (t));
12203 finish_then_clause (stmt);
12205 if (ELSE_CLAUSE (t))
12207 begin_else_clause (stmt);
12208 RECUR (ELSE_CLAUSE (t));
12209 finish_else_clause (stmt);
12212 finish_if_stmt (stmt);
12216 if (BIND_EXPR_BODY_BLOCK (t))
12217 stmt = begin_function_body ();
12219 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12220 ? BCS_TRY_BLOCK : 0);
12222 RECUR (BIND_EXPR_BODY (t));
12224 if (BIND_EXPR_BODY_BLOCK (t))
12225 finish_function_body (stmt);
12227 finish_compound_stmt (stmt);
12231 finish_break_stmt ();
12234 case CONTINUE_STMT:
12235 finish_continue_stmt ();
12239 stmt = begin_switch_stmt ();
12240 tmp = RECUR (SWITCH_STMT_COND (t));
12241 finish_switch_cond (tmp, stmt);
12242 RECUR (SWITCH_STMT_BODY (t));
12243 finish_switch_stmt (stmt);
12246 case CASE_LABEL_EXPR:
12247 finish_case_label (EXPR_LOCATION (t),
12248 RECUR (CASE_LOW (t)),
12249 RECUR (CASE_HIGH (t)));
12254 tree decl = LABEL_EXPR_LABEL (t);
12257 label = finish_label_stmt (DECL_NAME (decl));
12258 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12259 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12264 tmp = GOTO_DESTINATION (t);
12265 if (TREE_CODE (tmp) != LABEL_DECL)
12266 /* Computed goto's must be tsubst'd into. On the other hand,
12267 non-computed gotos must not be; the identifier in question
12268 will have no binding. */
12271 tmp = DECL_NAME (tmp);
12272 finish_goto_stmt (tmp);
12276 tmp = finish_asm_stmt
12277 (ASM_VOLATILE_P (t),
12278 RECUR (ASM_STRING (t)),
12279 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12280 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12281 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12282 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12284 tree asm_expr = tmp;
12285 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12286 asm_expr = TREE_OPERAND (asm_expr, 0);
12287 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12294 stmt = begin_try_block ();
12295 RECUR (TRY_STMTS (t));
12296 finish_cleanup_try_block (stmt);
12297 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12301 tree compound_stmt = NULL_TREE;
12303 if (FN_TRY_BLOCK_P (t))
12304 stmt = begin_function_try_block (&compound_stmt);
12306 stmt = begin_try_block ();
12308 RECUR (TRY_STMTS (t));
12310 if (FN_TRY_BLOCK_P (t))
12311 finish_function_try_block (stmt);
12313 finish_try_block (stmt);
12315 RECUR (TRY_HANDLERS (t));
12316 if (FN_TRY_BLOCK_P (t))
12317 finish_function_handler_sequence (stmt, compound_stmt);
12319 finish_handler_sequence (stmt);
12325 tree decl = HANDLER_PARMS (t);
12329 decl = tsubst (decl, args, complain, in_decl);
12330 /* Prevent instantiate_decl from trying to instantiate
12331 this variable. We've already done all that needs to be
12333 if (decl != error_mark_node)
12334 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12336 stmt = begin_handler ();
12337 finish_handler_parms (decl, stmt);
12338 RECUR (HANDLER_BODY (t));
12339 finish_handler (stmt);
12344 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12347 case STATIC_ASSERT:
12350 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12353 /*integral_constant_expression_p=*/true);
12354 finish_static_assert (condition,
12355 STATIC_ASSERT_MESSAGE (t),
12356 STATIC_ASSERT_SOURCE_LOCATION (t),
12357 /*member_p=*/false);
12362 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12363 args, complain, in_decl);
12364 stmt = begin_omp_parallel ();
12365 RECUR (OMP_PARALLEL_BODY (t));
12366 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12367 = OMP_PARALLEL_COMBINED (t);
12371 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12372 args, complain, in_decl);
12373 stmt = begin_omp_task ();
12374 RECUR (OMP_TASK_BODY (t));
12375 finish_omp_task (tmp, stmt);
12380 tree clauses, body, pre_body;
12381 tree declv, initv, condv, incrv;
12384 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12385 args, complain, in_decl);
12386 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12387 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12388 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12389 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12391 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12392 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12393 &clauses, args, complain, in_decl,
12394 integral_constant_expression_p);
12396 stmt = begin_omp_structured_block ();
12398 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12399 if (TREE_VEC_ELT (initv, i) == NULL
12400 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12401 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12402 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12404 tree init = RECUR (TREE_VEC_ELT (initv, i));
12405 gcc_assert (init == TREE_VEC_ELT (declv, i));
12406 TREE_VEC_ELT (initv, i) = NULL_TREE;
12410 tree decl_expr = TREE_VEC_ELT (initv, i);
12411 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12412 gcc_assert (init != NULL);
12413 TREE_VEC_ELT (initv, i) = RECUR (init);
12414 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12416 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12419 pre_body = push_stmt_list ();
12420 RECUR (OMP_FOR_PRE_BODY (t));
12421 pre_body = pop_stmt_list (pre_body);
12423 body = push_stmt_list ();
12424 RECUR (OMP_FOR_BODY (t));
12425 body = pop_stmt_list (body);
12427 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12428 body, pre_body, clauses);
12430 add_stmt (finish_omp_structured_block (stmt));
12436 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12437 stmt = push_stmt_list ();
12438 RECUR (OMP_BODY (t));
12439 stmt = pop_stmt_list (stmt);
12442 OMP_BODY (t) = stmt;
12443 OMP_CLAUSES (t) = tmp;
12451 stmt = push_stmt_list ();
12452 RECUR (OMP_BODY (t));
12453 stmt = pop_stmt_list (stmt);
12456 OMP_BODY (t) = stmt;
12461 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12463 tree op1 = TREE_OPERAND (t, 1);
12464 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12465 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12466 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12470 case EXPR_PACK_EXPANSION:
12471 error ("invalid use of pack expansion expression");
12472 return error_mark_node;
12474 case NONTYPE_ARGUMENT_PACK:
12475 error ("use %<...%> to expand argument pack");
12476 return error_mark_node;
12479 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12481 return tsubst_copy_and_build (t, args, complain, in_decl,
12482 /*function_p=*/false,
12483 integral_constant_expression_p);
12490 /* T is a postfix-expression that is not being used in a function
12491 call. Return the substituted version of T. */
12494 tsubst_non_call_postfix_expression (tree t, tree args,
12495 tsubst_flags_t complain,
12498 if (TREE_CODE (t) == SCOPE_REF)
12499 t = tsubst_qualified_id (t, args, complain, in_decl,
12500 /*done=*/false, /*address_p=*/false);
12502 t = tsubst_copy_and_build (t, args, complain, in_decl,
12503 /*function_p=*/false,
12504 /*integral_constant_expression_p=*/false);
12509 /* Like tsubst but deals with expressions and performs semantic
12510 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12513 tsubst_copy_and_build (tree t,
12515 tsubst_flags_t complain,
12518 bool integral_constant_expression_p)
12520 #define RECUR(NODE) \
12521 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12522 /*function_p=*/false, \
12523 integral_constant_expression_p)
12527 if (t == NULL_TREE || t == error_mark_node)
12530 switch (TREE_CODE (t))
12534 /* Fall through. */
12535 case IDENTIFIER_NODE:
12539 bool non_integral_constant_expression_p;
12540 const char *error_msg;
12542 if (IDENTIFIER_TYPENAME_P (t))
12544 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12545 t = mangle_conv_op_name_for_type (new_type);
12548 /* Look up the name. */
12549 decl = lookup_name (t);
12551 /* By convention, expressions use ERROR_MARK_NODE to indicate
12552 failure, not NULL_TREE. */
12553 if (decl == NULL_TREE)
12554 decl = error_mark_node;
12556 decl = finish_id_expression (t, decl, NULL_TREE,
12558 integral_constant_expression_p,
12559 /*allow_non_integral_constant_expression_p=*/false,
12560 &non_integral_constant_expression_p,
12561 /*template_p=*/false,
12563 /*address_p=*/false,
12564 /*template_arg_p=*/false,
12569 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12570 decl = unqualified_name_lookup_error (decl);
12574 case TEMPLATE_ID_EXPR:
12577 tree templ = RECUR (TREE_OPERAND (t, 0));
12578 tree targs = TREE_OPERAND (t, 1);
12581 targs = tsubst_template_args (targs, args, complain, in_decl);
12583 if (TREE_CODE (templ) == COMPONENT_REF)
12585 object = TREE_OPERAND (templ, 0);
12586 templ = TREE_OPERAND (templ, 1);
12589 object = NULL_TREE;
12590 templ = lookup_template_function (templ, targs);
12593 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12594 object, templ, NULL_TREE);
12596 return baselink_for_fns (templ);
12601 tree r = RECUR (TREE_OPERAND (t, 0));
12603 if (REFERENCE_REF_P (t))
12605 /* A type conversion to reference type will be enclosed in
12606 such an indirect ref, but the substitution of the cast
12607 will have also added such an indirect ref. */
12608 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12609 r = convert_from_reference (r);
12612 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12618 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12619 RECUR (TREE_OPERAND (t, 0)));
12622 case REINTERPRET_CAST_EXPR:
12623 case CONST_CAST_EXPR:
12624 case DYNAMIC_CAST_EXPR:
12625 case STATIC_CAST_EXPR:
12630 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12631 if (integral_constant_expression_p
12632 && !cast_valid_in_integral_constant_expression_p (type))
12634 if (complain & tf_error)
12635 error ("a cast to a type other than an integral or "
12636 "enumeration type cannot appear in a constant-expression");
12637 return error_mark_node;
12640 op = RECUR (TREE_OPERAND (t, 0));
12642 switch (TREE_CODE (t))
12645 return build_functional_cast (type, op, complain);
12646 case REINTERPRET_CAST_EXPR:
12647 return build_reinterpret_cast (type, op, complain);
12648 case CONST_CAST_EXPR:
12649 return build_const_cast (type, op, complain);
12650 case DYNAMIC_CAST_EXPR:
12651 return build_dynamic_cast (type, op, complain);
12652 case STATIC_CAST_EXPR:
12653 return build_static_cast (type, op, complain);
12655 gcc_unreachable ();
12659 case POSTDECREMENT_EXPR:
12660 case POSTINCREMENT_EXPR:
12661 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12662 args, complain, in_decl);
12663 return build_x_unary_op (TREE_CODE (t), op1, complain);
12665 case PREDECREMENT_EXPR:
12666 case PREINCREMENT_EXPR:
12670 case TRUTH_NOT_EXPR:
12671 case UNARY_PLUS_EXPR: /* Unary + */
12672 case REALPART_EXPR:
12673 case IMAGPART_EXPR:
12674 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12678 op1 = TREE_OPERAND (t, 0);
12679 if (TREE_CODE (op1) == LABEL_DECL)
12680 return finish_label_address_expr (DECL_NAME (op1),
12681 EXPR_LOCATION (op1));
12682 if (TREE_CODE (op1) == SCOPE_REF)
12683 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12684 /*done=*/true, /*address_p=*/true);
12686 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12688 return build_x_unary_op (ADDR_EXPR, op1, complain);
12693 case TRUNC_DIV_EXPR:
12694 case CEIL_DIV_EXPR:
12695 case FLOOR_DIV_EXPR:
12696 case ROUND_DIV_EXPR:
12697 case EXACT_DIV_EXPR:
12701 case TRUNC_MOD_EXPR:
12702 case FLOOR_MOD_EXPR:
12703 case TRUTH_ANDIF_EXPR:
12704 case TRUTH_ORIF_EXPR:
12705 case TRUTH_AND_EXPR:
12706 case TRUTH_OR_EXPR:
12721 return build_x_binary_op
12723 RECUR (TREE_OPERAND (t, 0)),
12724 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12726 : TREE_CODE (TREE_OPERAND (t, 0))),
12727 RECUR (TREE_OPERAND (t, 1)),
12728 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12730 : TREE_CODE (TREE_OPERAND (t, 1))),
12731 /*overloaded_p=*/NULL,
12735 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12736 /*address_p=*/false);
12738 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12739 args, complain, in_decl);
12740 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12743 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12744 return tsubst_copy (t, args, complain, in_decl);
12748 op1 = TREE_OPERAND (t, 0);
12751 /* When there are no ARGS, we are trying to evaluate a
12752 non-dependent expression from the parser. Trying to do
12753 the substitutions may not work. */
12755 op1 = TREE_TYPE (op1);
12759 ++cp_unevaluated_operand;
12760 ++c_inhibit_evaluation_warnings;
12761 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12762 /*function_p=*/false,
12763 /*integral_constant_expression_p=*/false);
12764 --cp_unevaluated_operand;
12765 --c_inhibit_evaluation_warnings;
12768 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12769 complain & tf_error);
12771 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12772 complain & tf_error);
12774 case AT_ENCODE_EXPR:
12776 op1 = TREE_OPERAND (t, 0);
12777 ++cp_unevaluated_operand;
12778 ++c_inhibit_evaluation_warnings;
12779 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12780 /*function_p=*/false,
12781 /*integral_constant_expression_p=*/false);
12782 --cp_unevaluated_operand;
12783 --c_inhibit_evaluation_warnings;
12784 return objc_build_encode_expr (op1);
12787 case NOEXCEPT_EXPR:
12788 op1 = TREE_OPERAND (t, 0);
12789 ++cp_unevaluated_operand;
12790 ++c_inhibit_evaluation_warnings;
12791 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12792 /*function_p=*/false,
12793 /*integral_constant_expression_p=*/false);
12794 --cp_unevaluated_operand;
12795 --c_inhibit_evaluation_warnings;
12796 return finish_noexcept_expr (op1, complain);
12800 tree r = build_x_modify_expr
12801 (RECUR (TREE_OPERAND (t, 0)),
12802 TREE_CODE (TREE_OPERAND (t, 1)),
12803 RECUR (TREE_OPERAND (t, 2)),
12805 /* TREE_NO_WARNING must be set if either the expression was
12806 parenthesized or it uses an operator such as >>= rather
12807 than plain assignment. In the former case, it was already
12808 set and must be copied. In the latter case,
12809 build_x_modify_expr sets it and it must not be reset
12811 if (TREE_NO_WARNING (t))
12812 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12817 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12818 args, complain, in_decl);
12819 /* Remember that there was a reference to this entity. */
12822 return build_x_arrow (op1);
12826 tree placement = RECUR (TREE_OPERAND (t, 0));
12827 tree init = RECUR (TREE_OPERAND (t, 3));
12828 VEC(tree,gc) *placement_vec;
12829 VEC(tree,gc) *init_vec;
12832 if (placement == NULL_TREE)
12833 placement_vec = NULL;
12836 placement_vec = make_tree_vector ();
12837 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12838 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12841 /* If there was an initializer in the original tree, but it
12842 instantiated to an empty list, then we should pass a
12843 non-NULL empty vector to tell build_new that it was an
12844 empty initializer() rather than no initializer. This can
12845 only happen when the initializer is a pack expansion whose
12846 parameter packs are of length zero. */
12847 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12851 init_vec = make_tree_vector ();
12852 if (init == void_zero_node)
12853 gcc_assert (init_vec != NULL);
12856 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12857 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12861 ret = build_new (&placement_vec,
12862 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
12863 RECUR (TREE_OPERAND (t, 2)),
12865 NEW_EXPR_USE_GLOBAL (t),
12868 if (placement_vec != NULL)
12869 release_tree_vector (placement_vec);
12870 if (init_vec != NULL)
12871 release_tree_vector (init_vec);
12877 return delete_sanity
12878 (RECUR (TREE_OPERAND (t, 0)),
12879 RECUR (TREE_OPERAND (t, 1)),
12880 DELETE_EXPR_USE_VEC (t),
12881 DELETE_EXPR_USE_GLOBAL (t),
12884 case COMPOUND_EXPR:
12885 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12886 RECUR (TREE_OPERAND (t, 1)),
12892 VEC(tree,gc) *call_args;
12893 unsigned int nargs, i;
12898 function = CALL_EXPR_FN (t);
12899 /* When we parsed the expression, we determined whether or
12900 not Koenig lookup should be performed. */
12901 koenig_p = KOENIG_LOOKUP_P (t);
12902 if (TREE_CODE (function) == SCOPE_REF)
12904 qualified_p = true;
12905 function = tsubst_qualified_id (function, args, complain, in_decl,
12907 /*address_p=*/false);
12909 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
12911 /* Do nothing; calling tsubst_copy_and_build on an identifier
12912 would incorrectly perform unqualified lookup again.
12914 Note that we can also have an IDENTIFIER_NODE if the earlier
12915 unqualified lookup found a member function; in that case
12916 koenig_p will be false and we do want to do the lookup
12917 again to find the instantiated member function.
12919 FIXME but doing that causes c++/15272, so we need to stop
12920 using IDENTIFIER_NODE in that situation. */
12921 qualified_p = false;
12925 if (TREE_CODE (function) == COMPONENT_REF)
12927 tree op = TREE_OPERAND (function, 1);
12929 qualified_p = (TREE_CODE (op) == SCOPE_REF
12930 || (BASELINK_P (op)
12931 && BASELINK_QUALIFIED_P (op)));
12934 qualified_p = false;
12936 function = tsubst_copy_and_build (function, args, complain,
12939 integral_constant_expression_p);
12941 if (BASELINK_P (function))
12942 qualified_p = true;
12945 nargs = call_expr_nargs (t);
12946 call_args = make_tree_vector ();
12947 for (i = 0; i < nargs; ++i)
12949 tree arg = CALL_EXPR_ARG (t, i);
12951 if (!PACK_EXPANSION_P (arg))
12952 VEC_safe_push (tree, gc, call_args,
12953 RECUR (CALL_EXPR_ARG (t, i)));
12956 /* Expand the pack expansion and push each entry onto
12958 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12959 if (TREE_CODE (arg) == TREE_VEC)
12961 unsigned int len, j;
12963 len = TREE_VEC_LENGTH (arg);
12964 for (j = 0; j < len; ++j)
12966 tree value = TREE_VEC_ELT (arg, j);
12967 if (value != NULL_TREE)
12968 value = convert_from_reference (value);
12969 VEC_safe_push (tree, gc, call_args, value);
12974 /* A partial substitution. Add one entry. */
12975 VEC_safe_push (tree, gc, call_args, arg);
12980 /* We do not perform argument-dependent lookup if normal
12981 lookup finds a non-function, in accordance with the
12982 expected resolution of DR 218. */
12984 && ((is_overloaded_fn (function)
12985 /* If lookup found a member function, the Koenig lookup is
12986 not appropriate, even if an unqualified-name was used
12987 to denote the function. */
12988 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12989 || TREE_CODE (function) == IDENTIFIER_NODE)
12990 /* Only do this when substitution turns a dependent call
12991 into a non-dependent call. */
12992 && type_dependent_expression_p_push (t)
12993 && !any_type_dependent_arguments_p (call_args))
12994 function = perform_koenig_lookup (function, call_args, false,
12997 if (TREE_CODE (function) == IDENTIFIER_NODE
12998 && !any_type_dependent_arguments_p (call_args))
13000 if (koenig_p && (complain & tf_warning_or_error))
13002 /* For backwards compatibility and good diagnostics, try
13003 the unqualified lookup again if we aren't in SFINAE
13005 tree unq = (tsubst_copy_and_build
13006 (function, args, complain, in_decl, true,
13007 integral_constant_expression_p));
13008 if (unq != function)
13011 if (TREE_CODE (fn) == COMPONENT_REF)
13012 fn = TREE_OPERAND (fn, 1);
13013 if (is_overloaded_fn (fn))
13014 fn = get_first_fn (fn);
13015 permerror (EXPR_LOC_OR_HERE (t),
13016 "%qD was not declared in this scope, "
13017 "and no declarations were found by "
13018 "argument-dependent lookup at the point "
13019 "of instantiation", function);
13020 if (DECL_CLASS_SCOPE_P (fn))
13022 inform (EXPR_LOC_OR_HERE (t),
13023 "declarations in dependent base %qT are "
13024 "not found by unqualified lookup",
13025 DECL_CLASS_CONTEXT (fn));
13026 if (current_class_ptr)
13027 inform (EXPR_LOC_OR_HERE (t),
13028 "use %<this->%D%> instead", function);
13030 inform (EXPR_LOC_OR_HERE (t),
13031 "use %<%T::%D%> instead",
13032 current_class_name, function);
13035 inform (0, "%q+D declared here, later in the "
13036 "translation unit", fn);
13040 if (TREE_CODE (function) == IDENTIFIER_NODE)
13042 unqualified_name_lookup_error (function);
13043 release_tree_vector (call_args);
13044 return error_mark_node;
13048 /* Remember that there was a reference to this entity. */
13049 if (DECL_P (function))
13050 mark_used (function);
13052 if (TREE_CODE (function) == OFFSET_REF)
13053 ret = build_offset_ref_call_from_tree (function, &call_args);
13054 else if (TREE_CODE (function) == COMPONENT_REF)
13056 tree instance = TREE_OPERAND (function, 0);
13057 tree fn = TREE_OPERAND (function, 1);
13059 if (processing_template_decl
13060 && (type_dependent_expression_p (instance)
13061 || (!BASELINK_P (fn)
13062 && TREE_CODE (fn) != FIELD_DECL)
13063 || type_dependent_expression_p (fn)
13064 || any_type_dependent_arguments_p (call_args)))
13065 ret = build_nt_call_vec (function, call_args);
13066 else if (!BASELINK_P (fn))
13067 ret = finish_call_expr (function, &call_args,
13068 /*disallow_virtual=*/false,
13069 /*koenig_p=*/false,
13072 ret = (build_new_method_call
13074 &call_args, NULL_TREE,
13075 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13080 ret = finish_call_expr (function, &call_args,
13081 /*disallow_virtual=*/qualified_p,
13085 release_tree_vector (call_args);
13091 return build_x_conditional_expr
13092 (RECUR (TREE_OPERAND (t, 0)),
13093 RECUR (TREE_OPERAND (t, 1)),
13094 RECUR (TREE_OPERAND (t, 2)),
13097 case PSEUDO_DTOR_EXPR:
13098 return finish_pseudo_destructor_expr
13099 (RECUR (TREE_OPERAND (t, 0)),
13100 RECUR (TREE_OPERAND (t, 1)),
13101 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13105 tree purpose, value, chain;
13107 if (t == void_list_node)
13110 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13111 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13113 /* We have pack expansions, so expand those and
13114 create a new list out of it. */
13115 tree purposevec = NULL_TREE;
13116 tree valuevec = NULL_TREE;
13120 /* Expand the argument expressions. */
13121 if (TREE_PURPOSE (t))
13122 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13123 complain, in_decl);
13124 if (TREE_VALUE (t))
13125 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13126 complain, in_decl);
13128 /* Build the rest of the list. */
13129 chain = TREE_CHAIN (t);
13130 if (chain && chain != void_type_node)
13131 chain = RECUR (chain);
13133 /* Determine the number of arguments. */
13134 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13136 len = TREE_VEC_LENGTH (purposevec);
13137 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13139 else if (TREE_CODE (valuevec) == TREE_VEC)
13140 len = TREE_VEC_LENGTH (valuevec);
13143 /* Since we only performed a partial substitution into
13144 the argument pack, we only return a single list
13146 if (purposevec == TREE_PURPOSE (t)
13147 && valuevec == TREE_VALUE (t)
13148 && chain == TREE_CHAIN (t))
13151 return tree_cons (purposevec, valuevec, chain);
13154 /* Convert the argument vectors into a TREE_LIST */
13158 /* Grab the Ith values. */
13160 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13163 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13166 /* Build the list (backwards). */
13167 chain = tree_cons (purpose, value, chain);
13173 purpose = TREE_PURPOSE (t);
13175 purpose = RECUR (purpose);
13176 value = TREE_VALUE (t);
13178 value = RECUR (value);
13179 chain = TREE_CHAIN (t);
13180 if (chain && chain != void_type_node)
13181 chain = RECUR (chain);
13182 if (purpose == TREE_PURPOSE (t)
13183 && value == TREE_VALUE (t)
13184 && chain == TREE_CHAIN (t))
13186 return tree_cons (purpose, value, chain);
13189 case COMPONENT_REF:
13195 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13196 args, complain, in_decl);
13197 /* Remember that there was a reference to this entity. */
13198 if (DECL_P (object))
13199 mark_used (object);
13200 object_type = TREE_TYPE (object);
13202 member = TREE_OPERAND (t, 1);
13203 if (BASELINK_P (member))
13204 member = tsubst_baselink (member,
13205 non_reference (TREE_TYPE (object)),
13206 args, complain, in_decl);
13208 member = tsubst_copy (member, args, complain, in_decl);
13209 if (member == error_mark_node)
13210 return error_mark_node;
13212 if (object_type && !CLASS_TYPE_P (object_type))
13214 if (SCALAR_TYPE_P (object_type))
13216 tree s = NULL_TREE;
13217 tree dtor = member;
13219 if (TREE_CODE (dtor) == SCOPE_REF)
13221 s = TREE_OPERAND (dtor, 0);
13222 dtor = TREE_OPERAND (dtor, 1);
13224 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13226 dtor = TREE_OPERAND (dtor, 0);
13228 return finish_pseudo_destructor_expr (object, s, dtor);
13232 else if (TREE_CODE (member) == SCOPE_REF
13233 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13238 /* Lookup the template functions now that we know what the
13240 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13241 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13242 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13243 /*is_type_p=*/false,
13244 /*complain=*/false);
13245 if (BASELINK_P (member))
13247 BASELINK_FUNCTIONS (member)
13248 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13250 member = (adjust_result_of_qualified_name_lookup
13251 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13256 qualified_name_lookup_error (object_type, tmpl, member,
13258 return error_mark_node;
13261 else if (TREE_CODE (member) == SCOPE_REF
13262 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13263 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13265 if (complain & tf_error)
13267 if (TYPE_P (TREE_OPERAND (member, 0)))
13268 error ("%qT is not a class or namespace",
13269 TREE_OPERAND (member, 0));
13271 error ("%qD is not a class or namespace",
13272 TREE_OPERAND (member, 0));
13274 return error_mark_node;
13276 else if (TREE_CODE (member) == FIELD_DECL)
13277 return finish_non_static_data_member (member, object, NULL_TREE);
13279 return finish_class_member_access_expr (object, member,
13280 /*template_p=*/false,
13286 (RECUR (TREE_OPERAND (t, 0)));
13290 VEC(constructor_elt,gc) *n;
13291 constructor_elt *ce;
13292 unsigned HOST_WIDE_INT idx;
13293 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13294 bool process_index_p;
13296 bool need_copy_p = false;
13299 if (type == error_mark_node)
13300 return error_mark_node;
13302 /* digest_init will do the wrong thing if we let it. */
13303 if (type && TYPE_PTRMEMFUNC_P (type))
13306 /* We do not want to process the index of aggregate
13307 initializers as they are identifier nodes which will be
13308 looked up by digest_init. */
13309 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13311 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13312 newlen = VEC_length (constructor_elt, n);
13313 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13315 if (ce->index && process_index_p)
13316 ce->index = RECUR (ce->index);
13318 if (PACK_EXPANSION_P (ce->value))
13320 /* Substitute into the pack expansion. */
13321 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13324 if (ce->value == error_mark_node
13325 || PACK_EXPANSION_P (ce->value))
13327 else if (TREE_VEC_LENGTH (ce->value) == 1)
13328 /* Just move the argument into place. */
13329 ce->value = TREE_VEC_ELT (ce->value, 0);
13332 /* Update the length of the final CONSTRUCTOR
13333 arguments vector, and note that we will need to
13335 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13336 need_copy_p = true;
13340 ce->value = RECUR (ce->value);
13345 VEC(constructor_elt,gc) *old_n = n;
13347 n = VEC_alloc (constructor_elt, gc, newlen);
13348 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13350 if (TREE_CODE (ce->value) == TREE_VEC)
13352 int i, len = TREE_VEC_LENGTH (ce->value);
13353 for (i = 0; i < len; ++i)
13354 CONSTRUCTOR_APPEND_ELT (n, 0,
13355 TREE_VEC_ELT (ce->value, i));
13358 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13362 r = build_constructor (init_list_type_node, n);
13363 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13365 if (TREE_HAS_CONSTRUCTOR (t))
13366 return finish_compound_literal (type, r, complain);
13368 TREE_TYPE (r) = type;
13374 tree operand_0 = TREE_OPERAND (t, 0);
13375 if (TYPE_P (operand_0))
13377 operand_0 = tsubst (operand_0, args, complain, in_decl);
13378 return get_typeid (operand_0);
13382 operand_0 = RECUR (operand_0);
13383 return build_typeid (operand_0);
13394 tree r = tsubst_copy (t, args, complain, in_decl);
13396 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13397 /* If the original type was a reference, we'll be wrapped in
13398 the appropriate INDIRECT_REF. */
13399 r = convert_from_reference (r);
13404 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13405 tsubst (TREE_TYPE (t), args, complain, in_decl));
13407 case OFFSETOF_EXPR:
13408 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13412 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13413 complain, in_decl);
13415 tree type2 = TRAIT_EXPR_TYPE2 (t);
13417 type2 = tsubst_copy (type2, args, complain, in_decl);
13419 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13424 tree old_stmt_expr = cur_stmt_expr;
13425 tree stmt_expr = begin_stmt_expr ();
13427 cur_stmt_expr = stmt_expr;
13428 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13429 integral_constant_expression_p);
13430 stmt_expr = finish_stmt_expr (stmt_expr, false);
13431 cur_stmt_expr = old_stmt_expr;
13433 /* If the resulting list of expression statement is empty,
13434 fold it further into void_zero_node. */
13435 if (empty_expr_stmt_p (stmt_expr))
13436 stmt_expr = void_zero_node;
13442 t = tsubst_copy (t, args, complain, in_decl);
13443 /* As in finish_id_expression, we resolve enumeration constants
13444 to their underlying values. */
13445 if (TREE_CODE (t) == CONST_DECL)
13447 used_types_insert (TREE_TYPE (t));
13448 return DECL_INITIAL (t);
13454 tree r = build_lambda_expr ();
13456 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13457 TREE_TYPE (r) = type;
13458 CLASSTYPE_LAMBDA_EXPR (type) = r;
13460 LAMBDA_EXPR_LOCATION (r)
13461 = LAMBDA_EXPR_LOCATION (t);
13462 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13463 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13464 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13465 LAMBDA_EXPR_DISCRIMINATOR (r)
13466 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13467 LAMBDA_EXPR_CAPTURE_LIST (r)
13468 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13469 LAMBDA_EXPR_THIS_CAPTURE (r)
13470 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
13471 LAMBDA_EXPR_EXTRA_SCOPE (r)
13472 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13474 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13475 determine_visibility (TYPE_NAME (type));
13476 /* Now that we know visibility, instantiate the type so we have a
13477 declaration of the op() for later calls to lambda_function. */
13478 complete_type (type);
13480 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13482 apply_lambda_return_type (r, type);
13484 return build_lambda_object (r);
13488 /* We can get here for a constant initializer of non-dependent type.
13489 FIXME stop folding in cp_parser_initializer_clause. */
13490 gcc_assert (TREE_CONSTANT (t));
13492 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
13493 TREE_CONSTANT (r) = true;
13498 /* Handle Objective-C++ constructs, if appropriate. */
13501 = objcp_tsubst_copy_and_build (t, args, complain,
13502 in_decl, /*function_p=*/false);
13506 return tsubst_copy (t, args, complain, in_decl);
13512 /* Verify that the instantiated ARGS are valid. For type arguments,
13513 make sure that the type's linkage is ok. For non-type arguments,
13514 make sure they are constants if they are integral or enumerations.
13515 Emit an error under control of COMPLAIN, and return TRUE on error. */
13518 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13520 if (ARGUMENT_PACK_P (t))
13522 tree vec = ARGUMENT_PACK_ARGS (t);
13523 int len = TREE_VEC_LENGTH (vec);
13524 bool result = false;
13527 for (i = 0; i < len; ++i)
13528 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13532 else if (TYPE_P (t))
13534 /* [basic.link]: A name with no linkage (notably, the name
13535 of a class or enumeration declared in a local scope)
13536 shall not be used to declare an entity with linkage.
13537 This implies that names with no linkage cannot be used as
13540 DR 757 relaxes this restriction for C++0x. */
13541 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13542 : no_linkage_check (t, /*relaxed_p=*/false));
13546 /* DR 488 makes use of a type with no linkage cause
13547 type deduction to fail. */
13548 if (complain & tf_error)
13550 if (TYPE_ANONYMOUS_P (nt))
13551 error ("%qT is/uses anonymous type", t);
13553 error ("template argument for %qD uses local type %qT",
13558 /* In order to avoid all sorts of complications, we do not
13559 allow variably-modified types as template arguments. */
13560 else if (variably_modified_type_p (t, NULL_TREE))
13562 if (complain & tf_error)
13563 error ("%qT is a variably modified type", t);
13567 /* A non-type argument of integral or enumerated type must be a
13569 else if (TREE_TYPE (t)
13570 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13571 && !TREE_CONSTANT (t))
13573 if (complain & tf_error)
13574 error ("integral expression %qE is not constant", t);
13581 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13583 int ix, len = DECL_NTPARMS (tmpl);
13584 bool result = false;
13586 for (ix = 0; ix != len; ix++)
13588 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13591 if (result && (complain & tf_error))
13592 error (" trying to instantiate %qD", tmpl);
13596 /* In C++0x, it's possible to have a function template whose type depends
13597 on itself recursively. This is most obvious with decltype, but can also
13598 occur with enumeration scope (c++/48969). So we need to catch infinite
13599 recursion and reject the substitution at deduction time; this function
13600 will return error_mark_node for any repeated substitution.
13602 This also catches excessive recursion such as when f<N> depends on
13603 f<N-1> across all integers, and returns error_mark_node for all the
13604 substitutions back up to the initial one.
13606 This is, of course, not reentrant. */
13609 deduction_tsubst_fntype (tree fn, tree targs)
13611 static bool excessive_deduction_depth;
13612 static int deduction_depth;
13613 location_t save_loc = input_location;
13614 struct pending_template *old_last_pend = last_pending_template;
13616 tree fntype = TREE_TYPE (fn);
13620 if (excessive_deduction_depth)
13621 return error_mark_node;
13623 tinst = build_tree_list (fn, targs);
13624 if (!push_tinst_level (tinst))
13626 excessive_deduction_depth = true;
13628 return error_mark_node;
13631 input_location = DECL_SOURCE_LOCATION (fn);
13633 push_deduction_access_scope (fn);
13634 r = tsubst (fntype, targs, tf_none, NULL_TREE);
13635 pop_deduction_access_scope (fn);
13637 input_location = save_loc;
13639 if (excessive_deduction_depth)
13641 r = error_mark_node;
13642 if (deduction_depth == 0)
13643 /* Reset once we're all the way out. */
13644 excessive_deduction_depth = false;
13647 pop_tinst_level ();
13648 /* We can't free this if a pending_template entry is pointing at it. */
13649 if (last_pending_template == old_last_pend)
13654 /* Instantiate the indicated variable or function template TMPL with
13655 the template arguments in TARG_PTR. */
13658 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
13660 tree targ_ptr = orig_args;
13664 HOST_WIDE_INT saved_processing_template_decl;
13666 if (tmpl == error_mark_node)
13667 return error_mark_node;
13669 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13671 /* If this function is a clone, handle it specially. */
13672 if (DECL_CLONED_FUNCTION_P (tmpl))
13677 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13678 DECL_CLONED_FUNCTION. */
13679 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13680 targ_ptr, complain);
13681 if (spec == error_mark_node)
13682 return error_mark_node;
13684 /* Look for the clone. */
13685 FOR_EACH_CLONE (clone, spec)
13686 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13688 /* We should always have found the clone by now. */
13689 gcc_unreachable ();
13693 /* Check to see if we already have this specialization. */
13694 gen_tmpl = most_general_template (tmpl);
13695 if (tmpl != gen_tmpl)
13696 /* The TMPL is a partial instantiation. To get a full set of
13697 arguments we must add the arguments used to perform the
13698 partial instantiation. */
13699 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13702 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13703 but it doesn't seem to be on the hot path. */
13704 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13706 gcc_assert (tmpl == gen_tmpl
13707 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13709 || fndecl == NULL_TREE);
13711 if (spec != NULL_TREE)
13714 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13716 return error_mark_node;
13718 /* We are building a FUNCTION_DECL, during which the access of its
13719 parameters and return types have to be checked. However this
13720 FUNCTION_DECL which is the desired context for access checking
13721 is not built yet. We solve this chicken-and-egg problem by
13722 deferring all checks until we have the FUNCTION_DECL. */
13723 push_deferring_access_checks (dk_deferred);
13725 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13726 (because, for example, we have encountered a non-dependent
13727 function call in the body of a template function and must now
13728 determine which of several overloaded functions will be called),
13729 within the instantiation itself we are not processing a
13731 saved_processing_template_decl = processing_template_decl;
13732 processing_template_decl = 0;
13733 /* Substitute template parameters to obtain the specialization. */
13734 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13735 targ_ptr, complain, gen_tmpl);
13736 processing_template_decl = saved_processing_template_decl;
13737 if (fndecl == error_mark_node)
13738 return error_mark_node;
13740 /* Now we know the specialization, compute access previously
13742 push_access_scope (fndecl);
13744 /* Some typedefs referenced from within the template code need to be access
13745 checked at template instantiation time, i.e now. These types were
13746 added to the template at parsing time. Let's get those and perfom
13747 the acces checks then. */
13748 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13749 perform_deferred_access_checks ();
13750 pop_access_scope (fndecl);
13751 pop_deferring_access_checks ();
13753 /* The DECL_TI_TEMPLATE should always be the immediate parent
13754 template, not the most general template. */
13755 DECL_TI_TEMPLATE (fndecl) = tmpl;
13757 /* If we've just instantiated the main entry point for a function,
13758 instantiate all the alternate entry points as well. We do this
13759 by cloning the instantiation of the main entry point, not by
13760 instantiating the template clones. */
13761 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13762 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13767 /* Wrapper for instantiate_template_1. */
13770 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13773 timevar_push (TV_TEMPLATE_INST);
13774 ret = instantiate_template_1 (tmpl, orig_args, complain);
13775 timevar_pop (TV_TEMPLATE_INST);
13779 /* We're going to do deduction substitution on the type of TMPL, a function
13780 template. In C++11 mode, push into that access scope. In C++03 mode,
13781 disable access checking. */
13784 push_deduction_access_scope (tree tmpl)
13786 if (cxx_dialect >= cxx0x)
13787 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13789 push_deferring_access_checks (dk_no_check);
13792 /* And pop back out. */
13795 pop_deduction_access_scope (tree tmpl)
13797 if (cxx_dialect >= cxx0x)
13798 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13800 pop_deferring_access_checks ();
13803 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13804 NARGS elements of the arguments that are being used when calling
13805 it. TARGS is a vector into which the deduced template arguments
13808 Return zero for success, 2 for an incomplete match that doesn't resolve
13809 all the types, and 1 for complete failure. An error message will be
13810 printed only for an incomplete match.
13812 If FN is a conversion operator, or we are trying to produce a specific
13813 specialization, RETURN_TYPE is the return type desired.
13815 The EXPLICIT_TARGS are explicit template arguments provided via a
13818 The parameter STRICT is one of:
13821 We are deducing arguments for a function call, as in
13822 [temp.deduct.call].
13825 We are deducing arguments for a conversion function, as in
13826 [temp.deduct.conv].
13829 We are deducing arguments when doing an explicit instantiation
13830 as in [temp.explicit], when determining an explicit specialization
13831 as in [temp.expl.spec], or when taking the address of a function
13832 template, as in [temp.deduct.funcaddr]. */
13835 fn_type_unification (tree fn,
13836 tree explicit_targs,
13839 unsigned int nargs,
13841 unification_kind_t strict,
13847 bool incomplete_argument_packs_p = false;
13849 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13851 fntype = TREE_TYPE (fn);
13852 if (explicit_targs)
13856 The specified template arguments must match the template
13857 parameters in kind (i.e., type, nontype, template), and there
13858 must not be more arguments than there are parameters;
13859 otherwise type deduction fails.
13861 Nontype arguments must match the types of the corresponding
13862 nontype template parameters, or must be convertible to the
13863 types of the corresponding nontype parameters as specified in
13864 _temp.arg.nontype_, otherwise type deduction fails.
13866 All references in the function type of the function template
13867 to the corresponding template parameters are replaced by the
13868 specified template argument values. If a substitution in a
13869 template parameter or in the function type of the function
13870 template results in an invalid type, type deduction fails. */
13871 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13872 int i, len = TREE_VEC_LENGTH (tparms);
13873 tree converted_args;
13874 bool incomplete = false;
13876 if (explicit_targs == error_mark_node)
13880 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13881 /*require_all_args=*/false,
13882 /*use_default_args=*/false));
13883 if (converted_args == error_mark_node)
13886 /* Substitute the explicit args into the function type. This is
13887 necessary so that, for instance, explicitly declared function
13888 arguments can match null pointed constants. If we were given
13889 an incomplete set of explicit args, we must not do semantic
13890 processing during substitution as we could create partial
13892 for (i = 0; i < len; i++)
13894 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13895 bool parameter_pack = false;
13897 /* Dig out the actual parm. */
13898 if (TREE_CODE (parm) == TYPE_DECL
13899 || TREE_CODE (parm) == TEMPLATE_DECL)
13901 parm = TREE_TYPE (parm);
13902 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13904 else if (TREE_CODE (parm) == PARM_DECL)
13906 parm = DECL_INITIAL (parm);
13907 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13910 if (parameter_pack)
13914 template_parm_level_and_index (parm, &level, &idx);
13916 /* Mark the argument pack as "incomplete". We could
13917 still deduce more arguments during unification.
13918 We remove this mark in type_unification_real. */
13919 targ = TMPL_ARG (converted_args, level, idx);
13922 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13923 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13924 = ARGUMENT_PACK_ARGS (targ);
13927 /* We have some incomplete argument packs. */
13928 incomplete_argument_packs_p = true;
13932 if (incomplete_argument_packs_p)
13933 /* Any substitution is guaranteed to be incomplete if there
13934 are incomplete argument packs, because we can still deduce
13938 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13940 processing_template_decl += incomplete;
13941 fntype = deduction_tsubst_fntype (fn, converted_args);
13942 processing_template_decl -= incomplete;
13944 if (fntype == error_mark_node)
13947 /* Place the explicitly specified arguments in TARGS. */
13948 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13949 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13952 /* Never do unification on the 'this' parameter. */
13953 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13959 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13960 new_args = XALLOCAVEC (tree, nargs + 1);
13961 new_args[0] = return_type;
13962 memcpy (new_args + 1, args, nargs * sizeof (tree));
13967 /* We allow incomplete unification without an error message here
13968 because the standard doesn't seem to explicitly prohibit it. Our
13969 callers must be ready to deal with unification failures in any
13971 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13972 targs, parms, args, nargs, /*subr=*/0,
13975 /* Now that we have bindings for all of the template arguments,
13976 ensure that the arguments deduced for the template template
13977 parameters have compatible template parameter lists. We cannot
13978 check this property before we have deduced all template
13979 arguments, because the template parameter types of a template
13980 template parameter might depend on prior template parameters
13981 deduced after the template template parameter. The following
13982 ill-formed example illustrates this issue:
13984 template<typename T, template<T> class C> void f(C<5>, T);
13986 template<int N> struct X {};
13989 f(X<5>(), 5l); // error: template argument deduction fails
13992 The template parameter list of 'C' depends on the template type
13993 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13994 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13995 time that we deduce 'C'. */
13997 && !template_template_parm_bindings_ok_p
13998 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14002 /* All is well so far. Now, check:
14006 When all template arguments have been deduced, all uses of
14007 template parameters in nondeduced contexts are replaced with
14008 the corresponding deduced argument values. If the
14009 substitution results in an invalid type, as described above,
14010 type deduction fails. */
14012 tree substed = deduction_tsubst_fntype (fn, targs);
14013 if (substed == error_mark_node)
14016 /* If we're looking for an exact match, check that what we got
14017 is indeed an exact match. It might not be if some template
14018 parameters are used in non-deduced contexts. */
14019 if (strict == DEDUCE_EXACT)
14024 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14026 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14027 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14028 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14036 /* Adjust types before performing type deduction, as described in
14037 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14038 sections are symmetric. PARM is the type of a function parameter
14039 or the return type of the conversion function. ARG is the type of
14040 the argument passed to the call, or the type of the value
14041 initialized with the result of the conversion function.
14042 ARG_EXPR is the original argument expression, which may be null. */
14045 maybe_adjust_types_for_deduction (unification_kind_t strict,
14059 /* Swap PARM and ARG throughout the remainder of this
14060 function; the handling is precisely symmetric since PARM
14061 will initialize ARG rather than vice versa. */
14069 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14070 too, but here handle it by stripping the reference from PARM
14071 rather than by adding it to ARG. */
14072 if (TREE_CODE (*parm) == REFERENCE_TYPE
14073 && TYPE_REF_IS_RVALUE (*parm)
14074 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14075 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14076 && TREE_CODE (*arg) == REFERENCE_TYPE
14077 && !TYPE_REF_IS_RVALUE (*arg))
14078 *parm = TREE_TYPE (*parm);
14079 /* Nothing else to do in this case. */
14083 gcc_unreachable ();
14086 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14088 /* [temp.deduct.call]
14090 If P is not a reference type:
14092 --If A is an array type, the pointer type produced by the
14093 array-to-pointer standard conversion (_conv.array_) is
14094 used in place of A for type deduction; otherwise,
14096 --If A is a function type, the pointer type produced by
14097 the function-to-pointer standard conversion
14098 (_conv.func_) is used in place of A for type deduction;
14101 --If A is a cv-qualified type, the top level
14102 cv-qualifiers of A's type are ignored for type
14104 if (TREE_CODE (*arg) == ARRAY_TYPE)
14105 *arg = build_pointer_type (TREE_TYPE (*arg));
14106 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14107 *arg = build_pointer_type (*arg);
14109 *arg = TYPE_MAIN_VARIANT (*arg);
14112 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14113 of the form T&&, where T is a template parameter, and the argument
14114 is an lvalue, T is deduced as A& */
14115 if (TREE_CODE (*parm) == REFERENCE_TYPE
14116 && TYPE_REF_IS_RVALUE (*parm)
14117 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14118 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14119 && (arg_expr ? real_lvalue_p (arg_expr)
14120 /* try_one_overload doesn't provide an arg_expr, but
14121 functions are always lvalues. */
14122 : TREE_CODE (*arg) == FUNCTION_TYPE))
14123 *arg = build_reference_type (*arg);
14125 /* [temp.deduct.call]
14127 If P is a cv-qualified type, the top level cv-qualifiers
14128 of P's type are ignored for type deduction. If P is a
14129 reference type, the type referred to by P is used for
14131 *parm = TYPE_MAIN_VARIANT (*parm);
14132 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14134 *parm = TREE_TYPE (*parm);
14135 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14138 /* DR 322. For conversion deduction, remove a reference type on parm
14139 too (which has been swapped into ARG). */
14140 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14141 *arg = TREE_TYPE (*arg);
14146 /* Most parms like fn_type_unification.
14148 If SUBR is 1, we're being called recursively (to unify the
14149 arguments of a function or method parameter of a function
14153 type_unification_real (tree tparms,
14157 unsigned int xnargs,
14159 unification_kind_t strict,
14162 tree parm, arg, arg_expr;
14164 int ntparms = TREE_VEC_LENGTH (tparms);
14166 int saw_undeduced = 0;
14169 unsigned int nargs;
14172 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14173 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14174 gcc_assert (ntparms > 0);
14176 /* Reset the number of non-defaulted template arguments contained
14178 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14183 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
14184 | UNIFY_ALLOW_DERIVED);
14188 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14192 sub_strict = UNIFY_ALLOW_NONE;
14196 gcc_unreachable ();
14205 while (parms && parms != void_list_node
14208 parm = TREE_VALUE (parms);
14210 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
14211 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
14212 /* For a function parameter pack that occurs at the end of the
14213 parameter-declaration-list, the type A of each remaining
14214 argument of the call is compared with the type P of the
14215 declarator-id of the function parameter pack. */
14218 parms = TREE_CHAIN (parms);
14220 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
14221 /* For a function parameter pack that does not occur at the
14222 end of the parameter-declaration-list, the type of the
14223 parameter pack is a non-deduced context. */
14230 if (arg == error_mark_node)
14232 if (arg == unknown_type_node)
14233 /* We can't deduce anything from this, but we might get all the
14234 template args from other function args. */
14237 /* Conversions will be performed on a function argument that
14238 corresponds with a function parameter that contains only
14239 non-deducible template parameters and explicitly specified
14240 template parameters. */
14241 if (!uses_template_parms (parm))
14246 type = TREE_TYPE (arg);
14250 if (same_type_p (parm, type))
14252 if (strict != DEDUCE_EXACT
14253 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
14262 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14263 if (type_unknown_p (arg))
14265 /* [temp.deduct.type]
14267 A template-argument can be deduced from a pointer to
14268 function or pointer to member function argument if
14269 the set of overloaded functions does not contain
14270 function templates and at most one of a set of
14271 overloaded functions provides a unique match. */
14272 if (resolve_overloaded_unification
14273 (tparms, targs, parm, arg, strict, sub_strict))
14279 arg = unlowered_expr_type (arg);
14280 if (arg == error_mark_node)
14285 int arg_strict = sub_strict;
14288 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14291 if (arg == init_list_type_node && arg_expr)
14293 if (unify (tparms, targs, parm, arg, arg_strict))
14300 && parms != void_list_node
14301 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14303 /* Unify the remaining arguments with the pack expansion type. */
14305 tree parmvec = make_tree_vec (1);
14307 /* Allocate a TREE_VEC and copy in all of the arguments */
14308 argvec = make_tree_vec (nargs - ia);
14309 for (i = 0; ia < nargs; ++ia, ++i)
14310 TREE_VEC_ELT (argvec, i) = args[ia];
14312 /* Copy the parameter into parmvec. */
14313 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14314 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14315 /*call_args_p=*/true, /*subr=*/subr))
14318 /* Advance to the end of the list of parameters. */
14319 parms = TREE_CHAIN (parms);
14322 /* Fail if we've reached the end of the parm list, and more args
14323 are present, and the parm list isn't variadic. */
14324 if (ia < nargs && parms == void_list_node)
14326 /* Fail if parms are left and they don't have default values. */
14327 if (parms && parms != void_list_node
14328 && TREE_PURPOSE (parms) == NULL_TREE)
14333 /* Check to see if we need another pass before we start clearing
14334 ARGUMENT_PACK_INCOMPLETE_P. */
14335 for (i = 0; i < ntparms; i++)
14337 tree targ = TREE_VEC_ELT (targs, i);
14338 tree tparm = TREE_VEC_ELT (tparms, i);
14340 if (targ || tparm == error_mark_node)
14342 tparm = TREE_VALUE (tparm);
14344 /* If this is an undeduced nontype parameter that depends on
14345 a type parameter, try another pass; its type may have been
14346 deduced from a later argument than the one from which
14347 this parameter can be deduced. */
14348 if (TREE_CODE (tparm) == PARM_DECL
14349 && uses_template_parms (TREE_TYPE (tparm))
14350 && !saw_undeduced++)
14354 for (i = 0; i < ntparms; i++)
14356 tree targ = TREE_VEC_ELT (targs, i);
14357 tree tparm = TREE_VEC_ELT (tparms, i);
14359 /* Clear the "incomplete" flags on all argument packs now so that
14360 substituting them into later default arguments works. */
14361 if (targ && ARGUMENT_PACK_P (targ))
14363 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14364 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14367 if (targ || tparm == error_mark_node)
14369 tparm = TREE_VALUE (tparm);
14371 /* Core issue #226 (C++0x) [temp.deduct]:
14373 If a template argument has not been deduced, its
14374 default template argument, if any, is used.
14376 When we are in C++98 mode, TREE_PURPOSE will either
14377 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14378 to explicitly check cxx_dialect here. */
14379 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14381 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14382 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14383 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14384 arg = convert_template_argument (parm, arg, targs, tf_none,
14386 if (arg == error_mark_node)
14390 TREE_VEC_ELT (targs, i) = arg;
14391 /* The position of the first default template argument,
14392 is also the number of non-defaulted arguments in TARGS.
14394 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14395 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14400 /* If the type parameter is a parameter pack, then it will
14401 be deduced to an empty parameter pack. */
14402 if (template_parameter_pack_p (tparm))
14406 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14408 arg = make_node (NONTYPE_ARGUMENT_PACK);
14409 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14410 TREE_CONSTANT (arg) = 1;
14413 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14415 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14417 TREE_VEC_ELT (targs, i) = arg;
14424 #ifdef ENABLE_CHECKING
14425 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14426 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14432 /* Subroutine of type_unification_real. Args are like the variables
14433 at the call site. ARG is an overloaded function (or template-id);
14434 we try deducing template args from each of the overloads, and if
14435 only one succeeds, we go with that. Modifies TARGS and returns
14436 true on success. */
14439 resolve_overloaded_unification (tree tparms,
14443 unification_kind_t strict,
14446 tree tempargs = copy_node (targs);
14448 tree goodfn = NULL_TREE;
14451 if (TREE_CODE (arg) == ADDR_EXPR)
14453 arg = TREE_OPERAND (arg, 0);
14459 if (TREE_CODE (arg) == COMPONENT_REF)
14460 /* Handle `&x' where `x' is some static or non-static member
14462 arg = TREE_OPERAND (arg, 1);
14464 if (TREE_CODE (arg) == OFFSET_REF)
14465 arg = TREE_OPERAND (arg, 1);
14467 /* Strip baselink information. */
14468 if (BASELINK_P (arg))
14469 arg = BASELINK_FUNCTIONS (arg);
14471 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14473 /* If we got some explicit template args, we need to plug them into
14474 the affected templates before we try to unify, in case the
14475 explicit args will completely resolve the templates in question. */
14477 tree expl_subargs = TREE_OPERAND (arg, 1);
14478 arg = TREE_OPERAND (arg, 0);
14480 for (; arg; arg = OVL_NEXT (arg))
14482 tree fn = OVL_CURRENT (arg);
14483 tree subargs, elem;
14485 if (TREE_CODE (fn) != TEMPLATE_DECL)
14488 ++processing_template_decl;
14489 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14490 expl_subargs, /*check_ret=*/false);
14493 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14494 if (try_one_overload (tparms, targs, tempargs, parm,
14495 elem, strict, sub_strict, addr_p)
14496 && (!goodfn || !decls_match (goodfn, elem)))
14502 --processing_template_decl;
14505 else if (TREE_CODE (arg) != OVERLOAD
14506 && TREE_CODE (arg) != FUNCTION_DECL)
14507 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14508 -- but the deduction does not succeed because the expression is
14509 not just the function on its own. */
14512 for (; arg; arg = OVL_NEXT (arg))
14513 if (try_one_overload (tparms, targs, tempargs, parm,
14514 TREE_TYPE (OVL_CURRENT (arg)),
14515 strict, sub_strict, addr_p)
14516 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
14518 goodfn = OVL_CURRENT (arg);
14522 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14523 to function or pointer to member function argument if the set of
14524 overloaded functions does not contain function templates and at most
14525 one of a set of overloaded functions provides a unique match.
14527 So if we found multiple possibilities, we return success but don't
14528 deduce anything. */
14532 int i = TREE_VEC_LENGTH (targs);
14534 if (TREE_VEC_ELT (tempargs, i))
14535 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
14543 /* Core DR 115: In contexts where deduction is done and fails, or in
14544 contexts where deduction is not done, if a template argument list is
14545 specified and it, along with any default template arguments, identifies
14546 a single function template specialization, then the template-id is an
14547 lvalue for the function template specialization. */
14550 resolve_nondeduced_context (tree orig_expr)
14552 tree expr, offset, baselink;
14555 if (!type_unknown_p (orig_expr))
14560 offset = NULL_TREE;
14561 baselink = NULL_TREE;
14563 if (TREE_CODE (expr) == ADDR_EXPR)
14565 expr = TREE_OPERAND (expr, 0);
14568 if (TREE_CODE (expr) == OFFSET_REF)
14571 expr = TREE_OPERAND (expr, 1);
14573 if (TREE_CODE (expr) == BASELINK)
14576 expr = BASELINK_FUNCTIONS (expr);
14579 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
14582 tree goodfn = NULL_TREE;
14584 /* If we got some explicit template args, we need to plug them into
14585 the affected templates before we try to unify, in case the
14586 explicit args will completely resolve the templates in question. */
14588 tree expl_subargs = TREE_OPERAND (expr, 1);
14589 tree arg = TREE_OPERAND (expr, 0);
14590 tree badfn = NULL_TREE;
14591 tree badargs = NULL_TREE;
14593 for (; arg; arg = OVL_NEXT (arg))
14595 tree fn = OVL_CURRENT (arg);
14596 tree subargs, elem;
14598 if (TREE_CODE (fn) != TEMPLATE_DECL)
14601 ++processing_template_decl;
14602 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14603 expl_subargs, /*check_ret=*/false);
14604 if (subargs && !any_dependent_template_arguments_p (subargs))
14606 elem = instantiate_template (fn, subargs, tf_none);
14607 if (elem == error_mark_node)
14612 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
14618 --processing_template_decl;
14624 expr = build_baselink (BASELINK_BINFO (baselink),
14625 BASELINK_ACCESS_BINFO (baselink),
14626 expr, BASELINK_OPTYPE (baselink));
14630 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
14631 expr = build_offset_ref (base, expr, addr);
14634 expr = cp_build_addr_expr (expr, tf_warning_or_error);
14637 else if (good == 0 && badargs)
14638 /* There were no good options and at least one bad one, so let the
14639 user know what the problem is. */
14640 instantiate_template (badfn, badargs, tf_warning_or_error);
14645 /* Subroutine of resolve_overloaded_unification; does deduction for a single
14646 overload. Fills TARGS with any deduced arguments, or error_mark_node if
14647 different overloads deduce different arguments for a given parm.
14648 ADDR_P is true if the expression for which deduction is being
14649 performed was of the form "& fn" rather than simply "fn".
14651 Returns 1 on success. */
14654 try_one_overload (tree tparms,
14659 unification_kind_t strict,
14667 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14668 to function or pointer to member function argument if the set of
14669 overloaded functions does not contain function templates and at most
14670 one of a set of overloaded functions provides a unique match.
14672 So if this is a template, just return success. */
14674 if (uses_template_parms (arg))
14677 if (TREE_CODE (arg) == METHOD_TYPE)
14678 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14680 arg = build_pointer_type (arg);
14682 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14684 /* We don't copy orig_targs for this because if we have already deduced
14685 some template args from previous args, unify would complain when we
14686 try to deduce a template parameter for the same argument, even though
14687 there isn't really a conflict. */
14688 nargs = TREE_VEC_LENGTH (targs);
14689 tempargs = make_tree_vec (nargs);
14691 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14694 /* First make sure we didn't deduce anything that conflicts with
14695 explicitly specified args. */
14696 for (i = nargs; i--; )
14698 tree elt = TREE_VEC_ELT (tempargs, i);
14699 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14703 else if (uses_template_parms (elt))
14704 /* Since we're unifying against ourselves, we will fill in
14705 template args used in the function parm list with our own
14706 template parms. Discard them. */
14707 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14708 else if (oldelt && !template_args_equal (oldelt, elt))
14712 for (i = nargs; i--; )
14714 tree elt = TREE_VEC_ELT (tempargs, i);
14717 TREE_VEC_ELT (targs, i) = elt;
14723 /* PARM is a template class (perhaps with unbound template
14724 parameters). ARG is a fully instantiated type. If ARG can be
14725 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14726 TARGS are as for unify. */
14729 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14731 tree copy_of_targs;
14733 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14734 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14735 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14738 /* We need to make a new template argument vector for the call to
14739 unify. If we used TARGS, we'd clutter it up with the result of
14740 the attempted unification, even if this class didn't work out.
14741 We also don't want to commit ourselves to all the unifications
14742 we've already done, since unification is supposed to be done on
14743 an argument-by-argument basis. In other words, consider the
14744 following pathological case:
14746 template <int I, int J, int K>
14749 template <int I, int J>
14750 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14752 template <int I, int J, int K>
14753 void f(S<I, J, K>, S<I, I, I>);
14762 Now, by the time we consider the unification involving `s2', we
14763 already know that we must have `f<0, 0, 0>'. But, even though
14764 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14765 because there are two ways to unify base classes of S<0, 1, 2>
14766 with S<I, I, I>. If we kept the already deduced knowledge, we
14767 would reject the possibility I=1. */
14768 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14770 /* If unification failed, we're done. */
14771 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14772 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14778 /* Given a template type PARM and a class type ARG, find the unique
14779 base type in ARG that is an instance of PARM. We do not examine
14780 ARG itself; only its base-classes. If there is not exactly one
14781 appropriate base class, return NULL_TREE. PARM may be the type of
14782 a partial specialization, as well as a plain template type. Used
14786 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14788 tree rval = NULL_TREE;
14791 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14793 binfo = TYPE_BINFO (complete_type (arg));
14795 /* The type could not be completed. */
14798 /* Walk in inheritance graph order. The search order is not
14799 important, and this avoids multiple walks of virtual bases. */
14800 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14802 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14806 /* If there is more than one satisfactory baseclass, then:
14810 If they yield more than one possible deduced A, the type
14814 if (rval && !same_type_p (r, rval))
14824 /* Returns the level of DECL, which declares a template parameter. */
14827 template_decl_level (tree decl)
14829 switch (TREE_CODE (decl))
14832 case TEMPLATE_DECL:
14833 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14836 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14839 gcc_unreachable ();
14844 /* Decide whether ARG can be unified with PARM, considering only the
14845 cv-qualifiers of each type, given STRICT as documented for unify.
14846 Returns nonzero iff the unification is OK on that basis. */
14849 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14851 int arg_quals = cp_type_quals (arg);
14852 int parm_quals = cp_type_quals (parm);
14854 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14855 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14857 /* Although a CVR qualifier is ignored when being applied to a
14858 substituted template parameter ([8.3.2]/1 for example), that
14859 does not allow us to unify "const T" with "int&" because both
14860 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14861 It is ok when we're allowing additional CV qualifiers
14862 at the outer level [14.8.2.1]/3,1st bullet. */
14863 if ((TREE_CODE (arg) == REFERENCE_TYPE
14864 || TREE_CODE (arg) == FUNCTION_TYPE
14865 || TREE_CODE (arg) == METHOD_TYPE)
14866 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14869 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14870 && (parm_quals & TYPE_QUAL_RESTRICT))
14874 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14875 && (arg_quals & parm_quals) != parm_quals)
14878 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14879 && (parm_quals & arg_quals) != arg_quals)
14885 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14887 template_parm_level_and_index (tree parm, int* level, int* index)
14889 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14890 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14891 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14893 *index = TEMPLATE_TYPE_IDX (parm);
14894 *level = TEMPLATE_TYPE_LEVEL (parm);
14898 *index = TEMPLATE_PARM_IDX (parm);
14899 *level = TEMPLATE_PARM_LEVEL (parm);
14903 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14904 expansion at the end of PACKED_PARMS. Returns 0 if the type
14905 deduction succeeds, 1 otherwise. STRICT is the same as in
14906 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14907 call argument list. We'll need to adjust the arguments to make them
14908 types. SUBR tells us if this is from a recursive call to
14909 type_unification_real. */
14911 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14912 tree packed_args, int strict, bool call_args_p,
14916 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14917 tree pattern = PACK_EXPANSION_PATTERN (parm);
14918 tree pack, packs = NULL_TREE;
14919 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14920 int len = TREE_VEC_LENGTH (packed_args);
14922 /* Determine the parameter packs we will be deducing from the
14923 pattern, and record their current deductions. */
14924 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14925 pack; pack = TREE_CHAIN (pack))
14927 tree parm_pack = TREE_VALUE (pack);
14930 /* Determine the index and level of this parameter pack. */
14931 template_parm_level_and_index (parm_pack, &level, &idx);
14933 /* Keep track of the parameter packs and their corresponding
14935 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14936 TREE_TYPE (packs) = make_tree_vec (len - start);
14939 /* Loop through all of the arguments that have not yet been
14940 unified and unify each with the pattern. */
14941 for (i = start; i < len; i++)
14943 tree parm = pattern;
14945 /* For each parameter pack, clear out the deduced value so that
14946 we can deduce it again. */
14947 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14950 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14952 TMPL_ARG (targs, level, idx) = NULL_TREE;
14955 /* Unify the pattern with the current argument. */
14957 tree arg = TREE_VEC_ELT (packed_args, i);
14958 tree arg_expr = NULL_TREE;
14959 int arg_strict = strict;
14960 bool skip_arg_p = false;
14966 /* This mirrors what we do in type_unification_real. */
14970 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14971 | UNIFY_ALLOW_MORE_CV_QUAL
14972 | UNIFY_ALLOW_DERIVED);
14976 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14980 sub_strict = UNIFY_ALLOW_NONE;
14984 gcc_unreachable ();
14989 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14990 if (type_unknown_p (arg))
14992 /* [temp.deduct.type] A template-argument can be
14993 deduced from a pointer to function or pointer
14994 to member function argument if the set of
14995 overloaded functions does not contain function
14996 templates and at most one of a set of
14997 overloaded functions provides a unique
15000 if (resolve_overloaded_unification
15001 (tparms, targs, parm, arg,
15002 (unification_kind_t) strict,
15012 arg = unlowered_expr_type (arg);
15013 if (arg == error_mark_node)
15018 arg_strict = sub_strict;
15022 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
15023 &parm, &arg, arg_expr);
15028 /* For deduction from an init-list we need the actual list. */
15029 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15031 if (unify (tparms, targs, parm, arg, arg_strict))
15036 /* For each parameter pack, collect the deduced value. */
15037 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15040 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15042 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15043 TMPL_ARG (targs, level, idx);
15047 /* Verify that the results of unification with the parameter packs
15048 produce results consistent with what we've seen before, and make
15049 the deduced argument packs available. */
15050 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15052 tree old_pack = TREE_VALUE (pack);
15053 tree new_args = TREE_TYPE (pack);
15054 int i, len = TREE_VEC_LENGTH (new_args);
15056 bool nondeduced_p = false;
15058 /* By default keep the original deduced argument pack.
15059 If necessary, more specific code is going to update the
15060 resulting deduced argument later down in this function. */
15061 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15062 TMPL_ARG (targs, level, idx) = old_pack;
15064 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15065 actually deduce anything. */
15066 for (i = 0; i < len && !nondeduced_p; ++i)
15067 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15068 nondeduced_p = true;
15072 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15074 /* Prepend the explicit arguments onto NEW_ARGS. */
15075 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15076 tree old_args = new_args;
15077 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
15078 int len = explicit_len + TREE_VEC_LENGTH (old_args);
15080 /* Copy the explicit arguments. */
15081 new_args = make_tree_vec (len);
15082 for (i = 0; i < explicit_len; i++)
15083 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
15085 /* Copy the deduced arguments. */
15086 for (; i < len; i++)
15087 TREE_VEC_ELT (new_args, i) =
15088 TREE_VEC_ELT (old_args, i - explicit_len);
15094 /* Build the deduced *_ARGUMENT_PACK. */
15095 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15097 result = make_node (NONTYPE_ARGUMENT_PACK);
15098 TREE_TYPE (result) =
15099 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15100 TREE_CONSTANT (result) = 1;
15103 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15105 SET_ARGUMENT_PACK_ARGS (result, new_args);
15107 /* Note the deduced argument packs for this parameter
15109 TMPL_ARG (targs, level, idx) = result;
15111 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15112 && (ARGUMENT_PACK_ARGS (old_pack)
15113 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15115 /* We only had the explicitly-provided arguments before, but
15116 now we have a complete set of arguments. */
15117 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15119 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15120 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15121 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15123 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
15125 /* Inconsistent unification of this parameter pack. */
15132 /* Deduce the value of template parameters. TPARMS is the (innermost)
15133 set of template parameters to a template. TARGS is the bindings
15134 for those template parameters, as determined thus far; TARGS may
15135 include template arguments for outer levels of template parameters
15136 as well. PARM is a parameter to a template function, or a
15137 subcomponent of that parameter; ARG is the corresponding argument.
15138 This function attempts to match PARM with ARG in a manner
15139 consistent with the existing assignments in TARGS. If more values
15140 are deduced, then TARGS is updated.
15142 Returns 0 if the type deduction succeeds, 1 otherwise. The
15143 parameter STRICT is a bitwise or of the following flags:
15146 Require an exact match between PARM and ARG.
15147 UNIFY_ALLOW_MORE_CV_QUAL:
15148 Allow the deduced ARG to be more cv-qualified (by qualification
15149 conversion) than ARG.
15150 UNIFY_ALLOW_LESS_CV_QUAL:
15151 Allow the deduced ARG to be less cv-qualified than ARG.
15152 UNIFY_ALLOW_DERIVED:
15153 Allow the deduced ARG to be a template base class of ARG,
15154 or a pointer to a template base class of the type pointed to by
15156 UNIFY_ALLOW_INTEGER:
15157 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15158 case for more information.
15159 UNIFY_ALLOW_OUTER_LEVEL:
15160 This is the outermost level of a deduction. Used to determine validity
15161 of qualification conversions. A valid qualification conversion must
15162 have const qualified pointers leading up to the inner type which
15163 requires additional CV quals, except at the outer level, where const
15164 is not required [conv.qual]. It would be normal to set this flag in
15165 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15166 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15167 This is the outermost level of a deduction, and PARM can be more CV
15168 qualified at this point.
15169 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15170 This is the outermost level of a deduction, and PARM can be less CV
15171 qualified at this point. */
15174 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
15179 int strict_in = strict;
15181 /* I don't think this will do the right thing with respect to types.
15182 But the only case I've seen it in so far has been array bounds, where
15183 signedness is the only information lost, and I think that will be
15185 while (TREE_CODE (parm) == NOP_EXPR)
15186 parm = TREE_OPERAND (parm, 0);
15188 if (arg == error_mark_node)
15190 if (arg == unknown_type_node
15191 || arg == init_list_type_node)
15192 /* We can't deduce anything from this, but we might get all the
15193 template args from other function args. */
15196 /* If PARM uses template parameters, then we can't bail out here,
15197 even if ARG == PARM, since we won't record unifications for the
15198 template parameters. We might need them if we're trying to
15199 figure out which of two things is more specialized. */
15200 if (arg == parm && !uses_template_parms (parm))
15203 /* Handle init lists early, so the rest of the function can assume
15204 we're dealing with a type. */
15205 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15209 tree orig_parm = parm;
15211 /* Replace T with std::initializer_list<T> for deduction. */
15212 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15213 && flag_deduce_init_list)
15214 parm = listify (parm);
15216 if (!is_std_init_list (parm))
15217 /* We can only deduce from an initializer list argument if the
15218 parameter is std::initializer_list; otherwise this is a
15219 non-deduced context. */
15222 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15224 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15226 int elt_strict = strict;
15228 if (elt == error_mark_node)
15231 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15233 tree type = TREE_TYPE (elt);
15234 /* It should only be possible to get here for a call. */
15235 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15236 elt_strict |= maybe_adjust_types_for_deduction
15237 (DEDUCE_CALL, &elttype, &type, elt);
15241 if (unify (tparms, targs, elttype, elt, elt_strict))
15245 /* If the std::initializer_list<T> deduction worked, replace the
15246 deduced A with std::initializer_list<A>. */
15247 if (orig_parm != parm)
15249 idx = TEMPLATE_TYPE_IDX (orig_parm);
15250 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15251 targ = listify (targ);
15252 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15257 /* Immediately reject some pairs that won't unify because of
15258 cv-qualification mismatches. */
15259 if (TREE_CODE (arg) == TREE_CODE (parm)
15261 /* It is the elements of the array which hold the cv quals of an array
15262 type, and the elements might be template type parms. We'll check
15263 when we recurse. */
15264 && TREE_CODE (arg) != ARRAY_TYPE
15265 /* We check the cv-qualifiers when unifying with template type
15266 parameters below. We want to allow ARG `const T' to unify with
15267 PARM `T' for example, when computing which of two templates
15268 is more specialized, for example. */
15269 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15270 && !check_cv_quals_for_unify (strict_in, arg, parm))
15273 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15274 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15275 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15276 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15277 strict &= ~UNIFY_ALLOW_DERIVED;
15278 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15279 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15281 switch (TREE_CODE (parm))
15283 case TYPENAME_TYPE:
15285 case UNBOUND_CLASS_TEMPLATE:
15286 /* In a type which contains a nested-name-specifier, template
15287 argument values cannot be deduced for template parameters used
15288 within the nested-name-specifier. */
15291 case TEMPLATE_TYPE_PARM:
15292 case TEMPLATE_TEMPLATE_PARM:
15293 case BOUND_TEMPLATE_TEMPLATE_PARM:
15294 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15295 if (tparm == error_mark_node)
15298 if (TEMPLATE_TYPE_LEVEL (parm)
15299 != template_decl_level (tparm))
15300 /* The PARM is not one we're trying to unify. Just check
15301 to see if it matches ARG. */
15302 return (TREE_CODE (arg) == TREE_CODE (parm)
15303 && same_type_p (parm, arg)) ? 0 : 1;
15304 idx = TEMPLATE_TYPE_IDX (parm);
15305 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15306 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15308 /* Check for mixed types and values. */
15309 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15310 && TREE_CODE (tparm) != TYPE_DECL)
15311 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15312 && TREE_CODE (tparm) != TEMPLATE_DECL))
15315 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15317 /* ARG must be constructed from a template class or a template
15318 template parameter. */
15319 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15320 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15324 tree parmvec = TYPE_TI_ARGS (parm);
15325 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15326 tree full_argvec = add_to_template_args (targs, argvec);
15328 = DECL_INNERMOST_TEMPLATE_PARMS
15329 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15331 int parm_variadic_p = 0;
15333 /* The resolution to DR150 makes clear that default
15334 arguments for an N-argument may not be used to bind T
15335 to a template template parameter with fewer than N
15336 parameters. It is not safe to permit the binding of
15337 default arguments as an extension, as that may change
15338 the meaning of a conforming program. Consider:
15340 struct Dense { static const unsigned int dim = 1; };
15342 template <template <typename> class View,
15344 void operator+(float, View<Block> const&);
15346 template <typename Block,
15347 unsigned int Dim = Block::dim>
15348 struct Lvalue_proxy { operator float() const; };
15352 Lvalue_proxy<Dense> p;
15357 Here, if Lvalue_proxy is permitted to bind to View, then
15358 the global operator+ will be used; if they are not, the
15359 Lvalue_proxy will be converted to float. */
15360 if (coerce_template_parms (parm_parms,
15362 TYPE_TI_TEMPLATE (parm),
15364 /*require_all_args=*/true,
15365 /*use_default_args=*/false)
15366 == error_mark_node)
15369 /* Deduce arguments T, i from TT<T> or TT<i>.
15370 We check each element of PARMVEC and ARGVEC individually
15371 rather than the whole TREE_VEC since they can have
15372 different number of elements. */
15374 parmvec = expand_template_argument_pack (parmvec);
15375 argvec = expand_template_argument_pack (argvec);
15377 len = TREE_VEC_LENGTH (parmvec);
15379 /* Check if the parameters end in a pack, making them
15382 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15383 parm_variadic_p = 1;
15385 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15388 for (i = 0; i < len - parm_variadic_p; ++i)
15390 if (unify (tparms, targs,
15391 TREE_VEC_ELT (parmvec, i),
15392 TREE_VEC_ELT (argvec, i),
15397 if (parm_variadic_p
15398 && unify_pack_expansion (tparms, targs,
15401 /*call_args_p=*/false,
15405 arg = TYPE_TI_TEMPLATE (arg);
15407 /* Fall through to deduce template name. */
15410 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15411 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15413 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15415 /* Simple cases: Value already set, does match or doesn't. */
15416 if (targ != NULL_TREE && template_args_equal (targ, arg))
15423 /* If PARM is `const T' and ARG is only `int', we don't have
15424 a match unless we are allowing additional qualification.
15425 If ARG is `const int' and PARM is just `T' that's OK;
15426 that binds `const int' to `T'. */
15427 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15431 /* Consider the case where ARG is `const volatile int' and
15432 PARM is `const T'. Then, T should be `volatile int'. */
15433 arg = cp_build_qualified_type_real
15434 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15435 if (arg == error_mark_node)
15438 /* Simple cases: Value already set, does match or doesn't. */
15439 if (targ != NULL_TREE && same_type_p (targ, arg))
15444 /* Make sure that ARG is not a variable-sized array. (Note
15445 that were talking about variable-sized arrays (like
15446 `int[n]'), rather than arrays of unknown size (like
15447 `int[]').) We'll get very confused by such a type since
15448 the bound of the array will not be computable in an
15449 instantiation. Besides, such types are not allowed in
15450 ISO C++, so we can do as we please here. */
15451 if (variably_modified_type_p (arg, NULL_TREE))
15454 /* Strip typedefs as in convert_template_argument. */
15455 arg = strip_typedefs (arg);
15458 /* If ARG is a parameter pack or an expansion, we cannot unify
15459 against it unless PARM is also a parameter pack. */
15460 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15461 && !template_parameter_pack_p (parm))
15464 /* If the argument deduction results is a METHOD_TYPE,
15465 then there is a problem.
15466 METHOD_TYPE doesn't map to any real C++ type the result of
15467 the deduction can not be of that type. */
15468 if (TREE_CODE (arg) == METHOD_TYPE)
15471 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15474 case TEMPLATE_PARM_INDEX:
15475 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15476 if (tparm == error_mark_node)
15479 if (TEMPLATE_PARM_LEVEL (parm)
15480 != template_decl_level (tparm))
15481 /* The PARM is not one we're trying to unify. Just check
15482 to see if it matches ARG. */
15483 return !(TREE_CODE (arg) == TREE_CODE (parm)
15484 && cp_tree_equal (parm, arg));
15486 idx = TEMPLATE_PARM_IDX (parm);
15487 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15490 return !cp_tree_equal (targ, arg);
15492 /* [temp.deduct.type] If, in the declaration of a function template
15493 with a non-type template-parameter, the non-type
15494 template-parameter is used in an expression in the function
15495 parameter-list and, if the corresponding template-argument is
15496 deduced, the template-argument type shall match the type of the
15497 template-parameter exactly, except that a template-argument
15498 deduced from an array bound may be of any integral type.
15499 The non-type parameter might use already deduced type parameters. */
15500 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
15501 if (!TREE_TYPE (arg))
15502 /* Template-parameter dependent expression. Just accept it for now.
15503 It will later be processed in convert_template_argument. */
15505 else if (same_type_p (TREE_TYPE (arg), tparm))
15507 else if ((strict & UNIFY_ALLOW_INTEGER)
15508 && (TREE_CODE (tparm) == INTEGER_TYPE
15509 || TREE_CODE (tparm) == BOOLEAN_TYPE))
15510 /* Convert the ARG to the type of PARM; the deduced non-type
15511 template argument must exactly match the types of the
15512 corresponding parameter. */
15513 arg = fold (build_nop (tparm, arg));
15514 else if (uses_template_parms (tparm))
15515 /* We haven't deduced the type of this parameter yet. Try again
15521 /* If ARG is a parameter pack or an expansion, we cannot unify
15522 against it unless PARM is also a parameter pack. */
15523 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15524 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
15527 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15532 /* A pointer-to-member constant can be unified only with
15533 another constant. */
15534 if (TREE_CODE (arg) != PTRMEM_CST)
15537 /* Just unify the class member. It would be useless (and possibly
15538 wrong, depending on the strict flags) to unify also
15539 PTRMEM_CST_CLASS, because we want to be sure that both parm and
15540 arg refer to the same variable, even if through different
15541 classes. For instance:
15543 struct A { int x; };
15546 Unification of &A::x and &B::x must succeed. */
15547 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
15548 PTRMEM_CST_MEMBER (arg), strict);
15553 if (TREE_CODE (arg) != POINTER_TYPE)
15556 /* [temp.deduct.call]
15558 A can be another pointer or pointer to member type that can
15559 be converted to the deduced A via a qualification
15560 conversion (_conv.qual_).
15562 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
15563 This will allow for additional cv-qualification of the
15564 pointed-to types if appropriate. */
15566 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
15567 /* The derived-to-base conversion only persists through one
15568 level of pointers. */
15569 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
15571 return unify (tparms, targs, TREE_TYPE (parm),
15572 TREE_TYPE (arg), strict);
15575 case REFERENCE_TYPE:
15576 if (TREE_CODE (arg) != REFERENCE_TYPE)
15578 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15579 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15582 if (TREE_CODE (arg) != ARRAY_TYPE)
15584 if ((TYPE_DOMAIN (parm) == NULL_TREE)
15585 != (TYPE_DOMAIN (arg) == NULL_TREE))
15587 if (TYPE_DOMAIN (parm) != NULL_TREE)
15594 /* Our representation of array types uses "N - 1" as the
15595 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
15596 not an integer constant. We cannot unify arbitrarily
15597 complex expressions, so we eliminate the MINUS_EXPRs
15599 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
15600 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
15603 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
15604 parm_max = TREE_OPERAND (parm_max, 0);
15606 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
15607 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
15610 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
15611 trying to unify the type of a variable with the type
15612 of a template parameter. For example:
15614 template <unsigned int N>
15615 void f (char (&) [N]);
15622 Here, the type of the ARG will be "int [g(i)]", and
15623 may be a SAVE_EXPR, etc. */
15624 if (TREE_CODE (arg_max) != MINUS_EXPR)
15626 arg_max = TREE_OPERAND (arg_max, 0);
15629 /* If only one of the bounds used a MINUS_EXPR, compensate
15630 by adding one to the other bound. */
15631 if (parm_cst && !arg_cst)
15632 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
15636 else if (arg_cst && !parm_cst)
15637 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
15642 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
15645 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15646 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15653 case ENUMERAL_TYPE:
15655 if (TREE_CODE (arg) != TREE_CODE (parm))
15658 /* We have already checked cv-qualification at the top of the
15660 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15663 /* As far as unification is concerned, this wins. Later checks
15664 will invalidate it if necessary. */
15667 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15668 /* Type INTEGER_CST can come from ordinary constant template args. */
15670 while (TREE_CODE (arg) == NOP_EXPR)
15671 arg = TREE_OPERAND (arg, 0);
15673 if (TREE_CODE (arg) != INTEGER_CST)
15675 return !tree_int_cst_equal (parm, arg);
15680 if (TREE_CODE (arg) != TREE_VEC)
15682 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15684 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15685 if (unify (tparms, targs,
15686 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15694 if (TREE_CODE (arg) != TREE_CODE (parm))
15697 if (TYPE_PTRMEMFUNC_P (parm))
15699 if (!TYPE_PTRMEMFUNC_P (arg))
15702 return unify (tparms, targs,
15703 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15704 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15708 if (CLASSTYPE_TEMPLATE_INFO (parm))
15710 tree t = NULL_TREE;
15712 if (strict_in & UNIFY_ALLOW_DERIVED)
15714 /* First, we try to unify the PARM and ARG directly. */
15715 t = try_class_unification (tparms, targs,
15720 /* Fallback to the special case allowed in
15721 [temp.deduct.call]:
15723 If P is a class, and P has the form
15724 template-id, then A can be a derived class of
15725 the deduced A. Likewise, if P is a pointer to
15726 a class of the form template-id, A can be a
15727 pointer to a derived class pointed to by the
15729 t = get_template_base (tparms, targs, parm, arg);
15735 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15736 && (CLASSTYPE_TI_TEMPLATE (parm)
15737 == CLASSTYPE_TI_TEMPLATE (arg)))
15738 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15739 Then, we should unify `int' and `U'. */
15742 /* There's no chance of unification succeeding. */
15745 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15746 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15748 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15753 case FUNCTION_TYPE:
15755 unsigned int nargs;
15760 if (TREE_CODE (arg) != TREE_CODE (parm))
15763 /* CV qualifications for methods can never be deduced, they must
15764 match exactly. We need to check them explicitly here,
15765 because type_unification_real treats them as any other
15766 cv-qualified parameter. */
15767 if (TREE_CODE (parm) == METHOD_TYPE
15768 && (!check_cv_quals_for_unify
15770 class_of_this_parm (arg),
15771 class_of_this_parm (parm))))
15774 if (unify (tparms, targs, TREE_TYPE (parm),
15775 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15778 nargs = list_length (TYPE_ARG_TYPES (arg));
15779 args = XALLOCAVEC (tree, nargs);
15780 for (a = TYPE_ARG_TYPES (arg), i = 0;
15781 a != NULL_TREE && a != void_list_node;
15782 a = TREE_CHAIN (a), ++i)
15783 args[i] = TREE_VALUE (a);
15786 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15787 args, nargs, 1, DEDUCE_EXACT,
15792 /* Unify a pointer to member with a pointer to member function, which
15793 deduces the type of the member as a function type. */
15794 if (TYPE_PTRMEMFUNC_P (arg))
15799 /* Check top-level cv qualifiers */
15800 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15803 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15804 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15807 /* Determine the type of the function we are unifying against. */
15808 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15810 build_function_type (TREE_TYPE (method_type),
15811 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15813 /* Extract the cv-qualifiers of the member function from the
15814 implicit object parameter and place them on the function
15815 type to be restored later. */
15816 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15817 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15820 if (TREE_CODE (arg) != OFFSET_TYPE)
15822 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15823 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15825 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15829 if (DECL_TEMPLATE_PARM_P (parm))
15830 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15831 if (arg != integral_constant_value (parm))
15836 case TEMPLATE_DECL:
15837 /* Matched cases are handled by the ARG == PARM test above. */
15841 /* A non-type template parameter that is a variable should be a
15842 an integral constant, in which case, it whould have been
15843 folded into its (constant) value. So we should not be getting
15844 a variable here. */
15845 gcc_unreachable ();
15847 case TYPE_ARGUMENT_PACK:
15848 case NONTYPE_ARGUMENT_PACK:
15850 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15851 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15852 int i, len = TREE_VEC_LENGTH (packed_parms);
15853 int argslen = TREE_VEC_LENGTH (packed_args);
15854 int parm_variadic_p = 0;
15856 for (i = 0; i < len; ++i)
15858 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15861 /* We can unify against something with a trailing
15863 parm_variadic_p = 1;
15865 /* Since there is something following the pack
15866 expansion, we cannot unify this template argument
15873 /* If we don't have enough arguments to satisfy the parameters
15874 (not counting the pack expression at the end), or we have
15875 too many arguments for a parameter list that doesn't end in
15876 a pack expression, we can't unify. */
15877 if (argslen < (len - parm_variadic_p)
15878 || (argslen > len && !parm_variadic_p))
15881 /* Unify all of the parameters that precede the (optional)
15882 pack expression. */
15883 for (i = 0; i < len - parm_variadic_p; ++i)
15885 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15886 TREE_VEC_ELT (packed_args, i), strict))
15890 if (parm_variadic_p)
15891 return unify_pack_expansion (tparms, targs,
15892 packed_parms, packed_args,
15893 strict, /*call_args_p=*/false,
15901 case DECLTYPE_TYPE:
15902 case UNDERLYING_TYPE:
15903 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
15904 or UNDERLYING_TYPE nodes. */
15908 /* Unification fails if we hit an error node. */
15912 /* An unresolved overload is a nondeduced context. */
15913 if (type_unknown_p (parm))
15915 gcc_assert (EXPR_P (parm));
15917 /* We must be looking at an expression. This can happen with
15921 void foo(S<I>, S<I + 2>);
15923 This is a "nondeduced context":
15927 The nondeduced contexts are:
15929 --A type that is a template-id in which one or more of
15930 the template-arguments is an expression that references
15931 a template-parameter.
15933 In these cases, we assume deduction succeeded, but don't
15934 actually infer any unifications. */
15936 if (!uses_template_parms (parm)
15937 && !template_args_equal (parm, arg))
15944 /* Note that DECL can be defined in this translation unit, if
15948 mark_definable (tree decl)
15951 DECL_NOT_REALLY_EXTERN (decl) = 1;
15952 FOR_EACH_CLONE (clone, decl)
15953 DECL_NOT_REALLY_EXTERN (clone) = 1;
15956 /* Called if RESULT is explicitly instantiated, or is a member of an
15957 explicitly instantiated class. */
15960 mark_decl_instantiated (tree result, int extern_p)
15962 SET_DECL_EXPLICIT_INSTANTIATION (result);
15964 /* If this entity has already been written out, it's too late to
15965 make any modifications. */
15966 if (TREE_ASM_WRITTEN (result))
15969 if (TREE_CODE (result) != FUNCTION_DECL)
15970 /* The TREE_PUBLIC flag for function declarations will have been
15971 set correctly by tsubst. */
15972 TREE_PUBLIC (result) = 1;
15974 /* This might have been set by an earlier implicit instantiation. */
15975 DECL_COMDAT (result) = 0;
15978 DECL_NOT_REALLY_EXTERN (result) = 0;
15981 mark_definable (result);
15982 /* Always make artificials weak. */
15983 if (DECL_ARTIFICIAL (result) && flag_weak)
15984 comdat_linkage (result);
15985 /* For WIN32 we also want to put explicit instantiations in
15986 linkonce sections. */
15987 else if (TREE_PUBLIC (result))
15988 maybe_make_one_only (result);
15991 /* If EXTERN_P, then this function will not be emitted -- unless
15992 followed by an explicit instantiation, at which point its linkage
15993 will be adjusted. If !EXTERN_P, then this function will be
15994 emitted here. In neither circumstance do we want
15995 import_export_decl to adjust the linkage. */
15996 DECL_INTERFACE_KNOWN (result) = 1;
15999 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16000 important template arguments. If any are missing, we check whether
16001 they're important by using error_mark_node for substituting into any
16002 args that were used for partial ordering (the ones between ARGS and END)
16003 and seeing if it bubbles up. */
16006 check_undeduced_parms (tree targs, tree args, tree end)
16008 bool found = false;
16010 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16011 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16014 TREE_VEC_ELT (targs, i) = error_mark_node;
16018 for (; args != end; args = TREE_CHAIN (args))
16020 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16021 if (substed == error_mark_node)
16028 /* Given two function templates PAT1 and PAT2, return:
16030 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16031 -1 if PAT2 is more specialized than PAT1.
16032 0 if neither is more specialized.
16034 LEN indicates the number of parameters we should consider
16035 (defaulted parameters should not be considered).
16037 The 1998 std underspecified function template partial ordering, and
16038 DR214 addresses the issue. We take pairs of arguments, one from
16039 each of the templates, and deduce them against each other. One of
16040 the templates will be more specialized if all the *other*
16041 template's arguments deduce against its arguments and at least one
16042 of its arguments *does* *not* deduce against the other template's
16043 corresponding argument. Deduction is done as for class templates.
16044 The arguments used in deduction have reference and top level cv
16045 qualifiers removed. Iff both arguments were originally reference
16046 types *and* deduction succeeds in both directions, the template
16047 with the more cv-qualified argument wins for that pairing (if
16048 neither is more cv-qualified, they both are equal). Unlike regular
16049 deduction, after all the arguments have been deduced in this way,
16050 we do *not* verify the deduced template argument values can be
16051 substituted into non-deduced contexts.
16053 The logic can be a bit confusing here, because we look at deduce1 and
16054 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16055 can find template arguments for pat1 to make arg1 look like arg2, that
16056 means that arg2 is at least as specialized as arg1. */
16059 more_specialized_fn (tree pat1, tree pat2, int len)
16061 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16062 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16063 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16064 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16065 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16066 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16067 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16068 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16069 tree origs1, origs2;
16070 bool lose1 = false;
16071 bool lose2 = false;
16073 /* Remove the this parameter from non-static member functions. If
16074 one is a non-static member function and the other is not a static
16075 member function, remove the first parameter from that function
16076 also. This situation occurs for operator functions where we
16077 locate both a member function (with this pointer) and non-member
16078 operator (with explicit first operand). */
16079 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16081 len--; /* LEN is the number of significant arguments for DECL1 */
16082 args1 = TREE_CHAIN (args1);
16083 if (!DECL_STATIC_FUNCTION_P (decl2))
16084 args2 = TREE_CHAIN (args2);
16086 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16088 args2 = TREE_CHAIN (args2);
16089 if (!DECL_STATIC_FUNCTION_P (decl1))
16092 args1 = TREE_CHAIN (args1);
16096 /* If only one is a conversion operator, they are unordered. */
16097 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16100 /* Consider the return type for a conversion function */
16101 if (DECL_CONV_FN_P (decl1))
16103 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16104 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16108 processing_template_decl++;
16114 /* Stop when an ellipsis is seen. */
16115 && args1 != NULL_TREE && args2 != NULL_TREE)
16117 tree arg1 = TREE_VALUE (args1);
16118 tree arg2 = TREE_VALUE (args2);
16119 int deduce1, deduce2;
16123 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16124 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16126 /* When both arguments are pack expansions, we need only
16127 unify the patterns themselves. */
16128 arg1 = PACK_EXPANSION_PATTERN (arg1);
16129 arg2 = PACK_EXPANSION_PATTERN (arg2);
16131 /* This is the last comparison we need to do. */
16135 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16137 arg1 = TREE_TYPE (arg1);
16138 quals1 = cp_type_quals (arg1);
16141 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16143 arg2 = TREE_TYPE (arg2);
16144 quals2 = cp_type_quals (arg2);
16147 if ((quals1 < 0) != (quals2 < 0))
16149 /* Only of the args is a reference, see if we should apply
16150 array/function pointer decay to it. This is not part of
16151 DR214, but is, IMHO, consistent with the deduction rules
16152 for the function call itself, and with our earlier
16153 implementation of the underspecified partial ordering
16154 rules. (nathan). */
16157 switch (TREE_CODE (arg1))
16160 arg1 = TREE_TYPE (arg1);
16162 case FUNCTION_TYPE:
16163 arg1 = build_pointer_type (arg1);
16172 switch (TREE_CODE (arg2))
16175 arg2 = TREE_TYPE (arg2);
16177 case FUNCTION_TYPE:
16178 arg2 = build_pointer_type (arg2);
16187 arg1 = TYPE_MAIN_VARIANT (arg1);
16188 arg2 = TYPE_MAIN_VARIANT (arg2);
16190 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16192 int i, len2 = list_length (args2);
16193 tree parmvec = make_tree_vec (1);
16194 tree argvec = make_tree_vec (len2);
16197 /* Setup the parameter vector, which contains only ARG1. */
16198 TREE_VEC_ELT (parmvec, 0) = arg1;
16200 /* Setup the argument vector, which contains the remaining
16202 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16203 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16205 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
16206 argvec, UNIFY_ALLOW_NONE,
16207 /*call_args_p=*/false,
16210 /* We cannot deduce in the other direction, because ARG1 is
16211 a pack expansion but ARG2 is not. */
16214 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16216 int i, len1 = list_length (args1);
16217 tree parmvec = make_tree_vec (1);
16218 tree argvec = make_tree_vec (len1);
16221 /* Setup the parameter vector, which contains only ARG1. */
16222 TREE_VEC_ELT (parmvec, 0) = arg2;
16224 /* Setup the argument vector, which contains the remaining
16226 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16227 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16229 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
16230 argvec, UNIFY_ALLOW_NONE,
16231 /*call_args_p=*/false,
16234 /* We cannot deduce in the other direction, because ARG2 is
16235 a pack expansion but ARG1 is not.*/
16241 /* The normal case, where neither argument is a pack
16243 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
16244 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
16247 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16248 arg2, then arg2 is not as specialized as arg1. */
16254 /* "If, for a given type, deduction succeeds in both directions
16255 (i.e., the types are identical after the transformations above)
16256 and if the type from the argument template is more cv-qualified
16257 than the type from the parameter template (as described above)
16258 that type is considered to be more specialized than the other. If
16259 neither type is more cv-qualified than the other then neither type
16260 is more specialized than the other." */
16262 if (deduce1 && deduce2
16263 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16265 if ((quals1 & quals2) == quals2)
16267 if ((quals1 & quals2) == quals1)
16271 if (lose1 && lose2)
16272 /* We've failed to deduce something in either direction.
16273 These must be unordered. */
16276 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16277 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16278 /* We have already processed all of the arguments in our
16279 handing of the pack expansion type. */
16282 args1 = TREE_CHAIN (args1);
16283 args2 = TREE_CHAIN (args2);
16286 /* "In most cases, all template parameters must have values in order for
16287 deduction to succeed, but for partial ordering purposes a template
16288 parameter may remain without a value provided it is not used in the
16289 types being used for partial ordering."
16291 Thus, if we are missing any of the targs1 we need to substitute into
16292 origs1, then pat2 is not as specialized as pat1. This can happen when
16293 there is a nondeduced context. */
16294 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16296 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16299 processing_template_decl--;
16301 /* All things being equal, if the next argument is a pack expansion
16302 for one function but not for the other, prefer the
16303 non-variadic function. FIXME this is bogus; see c++/41958. */
16305 && args1 && TREE_VALUE (args1)
16306 && args2 && TREE_VALUE (args2))
16308 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16309 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16312 if (lose1 == lose2)
16320 /* Determine which of two partial specializations is more specialized.
16322 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16323 to the first partial specialization. The TREE_VALUE is the
16324 innermost set of template parameters for the partial
16325 specialization. PAT2 is similar, but for the second template.
16327 Return 1 if the first partial specialization is more specialized;
16328 -1 if the second is more specialized; 0 if neither is more
16331 See [temp.class.order] for information about determining which of
16332 two templates is more specialized. */
16335 more_specialized_class (tree pat1, tree pat2)
16340 bool any_deductions = false;
16342 tmpl1 = TREE_TYPE (pat1);
16343 tmpl2 = TREE_TYPE (pat2);
16345 /* Just like what happens for functions, if we are ordering between
16346 different class template specializations, we may encounter dependent
16347 types in the arguments, and we need our dependency check functions
16348 to behave correctly. */
16349 ++processing_template_decl;
16350 targs = get_class_bindings (TREE_VALUE (pat1),
16351 CLASSTYPE_TI_ARGS (tmpl1),
16352 CLASSTYPE_TI_ARGS (tmpl2));
16356 any_deductions = true;
16359 targs = get_class_bindings (TREE_VALUE (pat2),
16360 CLASSTYPE_TI_ARGS (tmpl2),
16361 CLASSTYPE_TI_ARGS (tmpl1));
16365 any_deductions = true;
16367 --processing_template_decl;
16369 /* In the case of a tie where at least one of the class templates
16370 has a parameter pack at the end, the template with the most
16371 non-packed parameters wins. */
16374 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16375 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16377 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16378 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16379 int len1 = TREE_VEC_LENGTH (args1);
16380 int len2 = TREE_VEC_LENGTH (args2);
16382 /* We don't count the pack expansion at the end. */
16383 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16385 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16390 else if (len1 < len2)
16397 /* Return the template arguments that will produce the function signature
16398 DECL from the function template FN, with the explicit template
16399 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16400 also match. Return NULL_TREE if no satisfactory arguments could be
16404 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16406 int ntparms = DECL_NTPARMS (fn);
16407 tree targs = make_tree_vec (ntparms);
16409 tree decl_arg_types;
16411 unsigned int nargs, ix;
16414 /* Substitute the explicit template arguments into the type of DECL.
16415 The call to fn_type_unification will handle substitution into the
16417 decl_type = TREE_TYPE (decl);
16418 if (explicit_args && uses_template_parms (decl_type))
16421 tree converted_args;
16423 if (DECL_TEMPLATE_INFO (decl))
16424 tmpl = DECL_TI_TEMPLATE (decl);
16426 /* We can get here for some invalid specializations. */
16430 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16431 explicit_args, NULL_TREE,
16433 /*require_all_args=*/false,
16434 /*use_default_args=*/false);
16435 if (converted_args == error_mark_node)
16438 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16439 if (decl_type == error_mark_node)
16443 /* Never do unification on the 'this' parameter. */
16444 decl_arg_types = skip_artificial_parms_for (decl,
16445 TYPE_ARG_TYPES (decl_type));
16447 nargs = list_length (decl_arg_types);
16448 args = XALLOCAVEC (tree, nargs);
16449 for (arg = decl_arg_types, ix = 0;
16450 arg != NULL_TREE && arg != void_list_node;
16451 arg = TREE_CHAIN (arg), ++ix)
16452 args[ix] = TREE_VALUE (arg);
16454 if (fn_type_unification (fn, explicit_args, targs,
16456 (check_rettype || DECL_CONV_FN_P (fn)
16457 ? TREE_TYPE (decl_type) : NULL_TREE),
16458 DEDUCE_EXACT, LOOKUP_NORMAL))
16464 /* Return the innermost template arguments that, when applied to a
16465 template specialization whose innermost template parameters are
16466 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
16469 For example, suppose we have:
16471 template <class T, class U> struct S {};
16472 template <class T> struct S<T*, int> {};
16474 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
16475 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
16476 int}. The resulting vector will be {double}, indicating that `T'
16477 is bound to `double'. */
16480 get_class_bindings (tree tparms, tree spec_args, tree args)
16482 int i, ntparms = TREE_VEC_LENGTH (tparms);
16484 tree innermost_deduced_args;
16486 innermost_deduced_args = make_tree_vec (ntparms);
16487 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16489 deduced_args = copy_node (args);
16490 SET_TMPL_ARGS_LEVEL (deduced_args,
16491 TMPL_ARGS_DEPTH (deduced_args),
16492 innermost_deduced_args);
16495 deduced_args = innermost_deduced_args;
16497 if (unify (tparms, deduced_args,
16498 INNERMOST_TEMPLATE_ARGS (spec_args),
16499 INNERMOST_TEMPLATE_ARGS (args),
16503 for (i = 0; i < ntparms; ++i)
16504 if (! TREE_VEC_ELT (innermost_deduced_args, i))
16507 /* Verify that nondeduced template arguments agree with the type
16508 obtained from argument deduction.
16512 struct A { typedef int X; };
16513 template <class T, class U> struct C {};
16514 template <class T> struct C<T, typename T::X> {};
16516 Then with the instantiation `C<A, int>', we can deduce that
16517 `T' is `A' but unify () does not check whether `typename T::X'
16519 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
16520 if (spec_args == error_mark_node
16521 /* We only need to check the innermost arguments; the other
16522 arguments will always agree. */
16523 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
16524 INNERMOST_TEMPLATE_ARGS (args)))
16527 /* Now that we have bindings for all of the template arguments,
16528 ensure that the arguments deduced for the template template
16529 parameters have compatible template parameter lists. See the use
16530 of template_template_parm_bindings_ok_p in fn_type_unification
16531 for more information. */
16532 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
16535 return deduced_args;
16538 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
16539 Return the TREE_LIST node with the most specialized template, if
16540 any. If there is no most specialized template, the error_mark_node
16543 Note that this function does not look at, or modify, the
16544 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
16545 returned is one of the elements of INSTANTIATIONS, callers may
16546 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
16547 and retrieve it from the value returned. */
16550 most_specialized_instantiation (tree templates)
16554 ++processing_template_decl;
16557 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
16561 if (get_bindings (TREE_VALUE (champ),
16562 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16563 NULL_TREE, /*check_ret=*/false))
16566 if (get_bindings (TREE_VALUE (fn),
16567 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16568 NULL_TREE, /*check_ret=*/false))
16575 /* Equally specialized, move to next function. If there
16576 is no next function, nothing's most specialized. */
16577 fn = TREE_CHAIN (fn);
16585 /* Now verify that champ is better than everything earlier in the
16586 instantiation list. */
16587 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
16588 if (get_bindings (TREE_VALUE (champ),
16589 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16590 NULL_TREE, /*check_ret=*/false)
16591 || !get_bindings (TREE_VALUE (fn),
16592 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16593 NULL_TREE, /*check_ret=*/false))
16599 processing_template_decl--;
16602 return error_mark_node;
16607 /* If DECL is a specialization of some template, return the most
16608 general such template. Otherwise, returns NULL_TREE.
16610 For example, given:
16612 template <class T> struct S { template <class U> void f(U); };
16614 if TMPL is `template <class U> void S<int>::f(U)' this will return
16615 the full template. This function will not trace past partial
16616 specializations, however. For example, given in addition:
16618 template <class T> struct S<T*> { template <class U> void f(U); };
16620 if TMPL is `template <class U> void S<int*>::f(U)' this will return
16621 `template <class T> template <class U> S<T*>::f(U)'. */
16624 most_general_template (tree decl)
16626 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
16627 an immediate specialization. */
16628 if (TREE_CODE (decl) == FUNCTION_DECL)
16630 if (DECL_TEMPLATE_INFO (decl)) {
16631 decl = DECL_TI_TEMPLATE (decl);
16633 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
16634 template friend. */
16635 if (TREE_CODE (decl) != TEMPLATE_DECL)
16641 /* Look for more and more general templates. */
16642 while (DECL_TEMPLATE_INFO (decl))
16644 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
16645 (See cp-tree.h for details.) */
16646 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
16649 if (CLASS_TYPE_P (TREE_TYPE (decl))
16650 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
16653 /* Stop if we run into an explicitly specialized class template. */
16654 if (!DECL_NAMESPACE_SCOPE_P (decl)
16655 && DECL_CONTEXT (decl)
16656 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16659 decl = DECL_TI_TEMPLATE (decl);
16665 /* Return the most specialized of the class template partial
16666 specializations of TMPL which can produce TYPE, a specialization of
16667 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16668 a _TYPE node corresponding to the partial specialization, while the
16669 TREE_PURPOSE is the set of template arguments that must be
16670 substituted into the TREE_TYPE in order to generate TYPE.
16672 If the choice of partial specialization is ambiguous, a diagnostic
16673 is issued, and the error_mark_node is returned. If there are no
16674 partial specializations of TMPL matching TYPE, then NULL_TREE is
16678 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16680 tree list = NULL_TREE;
16686 tree outer_args = NULL_TREE;
16688 tmpl = most_general_template (tmpl);
16689 args = CLASSTYPE_TI_ARGS (type);
16691 /* For determining which partial specialization to use, only the
16692 innermost args are interesting. */
16693 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16695 outer_args = strip_innermost_template_args (args, 1);
16696 args = INNERMOST_TEMPLATE_ARGS (args);
16699 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16701 tree partial_spec_args;
16703 tree parms = TREE_VALUE (t);
16705 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16707 ++processing_template_decl;
16713 /* Discard the outer levels of args, and then substitute in the
16714 template args from the enclosing class. */
16715 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16716 partial_spec_args = tsubst_template_args
16717 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16719 /* PARMS already refers to just the innermost parms, but the
16720 template parms in partial_spec_args had their levels lowered
16721 by tsubst, so we need to do the same for the parm list. We
16722 can't just tsubst the TREE_VEC itself, as tsubst wants to
16723 treat a TREE_VEC as an argument vector. */
16724 parms = copy_node (parms);
16725 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16726 TREE_VEC_ELT (parms, i) =
16727 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16731 partial_spec_args =
16732 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16733 add_to_template_args (outer_args,
16734 partial_spec_args),
16736 /*require_all_args=*/true,
16737 /*use_default_args=*/true);
16739 --processing_template_decl;
16741 if (partial_spec_args == error_mark_node)
16742 return error_mark_node;
16744 spec_args = get_class_bindings (parms,
16750 spec_args = add_to_template_args (outer_args, spec_args);
16751 list = tree_cons (spec_args, TREE_VALUE (t), list);
16752 TREE_TYPE (list) = TREE_TYPE (t);
16759 ambiguous_p = false;
16762 t = TREE_CHAIN (t);
16763 for (; t; t = TREE_CHAIN (t))
16765 fate = more_specialized_class (champ, t);
16772 t = TREE_CHAIN (t);
16775 ambiguous_p = true;
16784 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16786 fate = more_specialized_class (champ, t);
16789 ambiguous_p = true;
16797 char *spaces = NULL;
16798 if (!(complain & tf_error))
16799 return error_mark_node;
16800 error ("ambiguous class template instantiation for %q#T", type);
16801 str = ngettext ("candidate is:", "candidates are:", list_length (list));
16802 for (t = list; t; t = TREE_CHAIN (t))
16804 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16805 spaces = spaces ? spaces : get_spaces (str);
16808 return error_mark_node;
16814 /* Explicitly instantiate DECL. */
16817 do_decl_instantiation (tree decl, tree storage)
16819 tree result = NULL_TREE;
16822 if (!decl || decl == error_mark_node)
16823 /* An error occurred, for which grokdeclarator has already issued
16824 an appropriate message. */
16826 else if (! DECL_LANG_SPECIFIC (decl))
16828 error ("explicit instantiation of non-template %q#D", decl);
16831 else if (TREE_CODE (decl) == VAR_DECL)
16833 /* There is an asymmetry here in the way VAR_DECLs and
16834 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16835 the latter, the DECL we get back will be marked as a
16836 template instantiation, and the appropriate
16837 DECL_TEMPLATE_INFO will be set up. This does not happen for
16838 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16839 should handle VAR_DECLs as it currently handles
16841 if (!DECL_CLASS_SCOPE_P (decl))
16843 error ("%qD is not a static data member of a class template", decl);
16846 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16847 if (!result || TREE_CODE (result) != VAR_DECL)
16849 error ("no matching template for %qD found", decl);
16852 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16854 error ("type %qT for explicit instantiation %qD does not match "
16855 "declared type %qT", TREE_TYPE (result), decl,
16860 else if (TREE_CODE (decl) != FUNCTION_DECL)
16862 error ("explicit instantiation of %q#D", decl);
16868 /* Check for various error cases. Note that if the explicit
16869 instantiation is valid the RESULT will currently be marked as an
16870 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16871 until we get here. */
16873 if (DECL_TEMPLATE_SPECIALIZATION (result))
16875 /* DR 259 [temp.spec].
16877 Both an explicit instantiation and a declaration of an explicit
16878 specialization shall not appear in a program unless the explicit
16879 instantiation follows a declaration of the explicit specialization.
16881 For a given set of template parameters, if an explicit
16882 instantiation of a template appears after a declaration of an
16883 explicit specialization for that template, the explicit
16884 instantiation has no effect. */
16887 else if (DECL_EXPLICIT_INSTANTIATION (result))
16891 No program shall explicitly instantiate any template more
16894 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16895 the first instantiation was `extern' and the second is not,
16896 and EXTERN_P for the opposite case. */
16897 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16898 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16899 /* If an "extern" explicit instantiation follows an ordinary
16900 explicit instantiation, the template is instantiated. */
16904 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16906 error ("no matching template for %qD found", result);
16909 else if (!DECL_TEMPLATE_INFO (result))
16911 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16915 if (storage == NULL_TREE)
16917 else if (storage == ridpointers[(int) RID_EXTERN])
16919 if (!in_system_header && (cxx_dialect == cxx98))
16920 pedwarn (input_location, OPT_pedantic,
16921 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16926 error ("storage class %qD applied to template instantiation", storage);
16928 check_explicit_instantiation_namespace (result);
16929 mark_decl_instantiated (result, extern_p);
16931 instantiate_decl (result, /*defer_ok=*/1,
16932 /*expl_inst_class_mem_p=*/false);
16936 mark_class_instantiated (tree t, int extern_p)
16938 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16939 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16940 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16941 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16944 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16945 rest_of_type_compilation (t, 1);
16949 /* Called from do_type_instantiation through binding_table_foreach to
16950 do recursive instantiation for the type bound in ENTRY. */
16952 bt_instantiate_type_proc (binding_entry entry, void *data)
16954 tree storage = *(tree *) data;
16956 if (MAYBE_CLASS_TYPE_P (entry->type)
16957 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16958 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16961 /* Called from do_type_instantiation to instantiate a member
16962 (a member function or a static member variable) of an
16963 explicitly instantiated class template. */
16965 instantiate_class_member (tree decl, int extern_p)
16967 mark_decl_instantiated (decl, extern_p);
16969 instantiate_decl (decl, /*defer_ok=*/1,
16970 /*expl_inst_class_mem_p=*/true);
16973 /* Perform an explicit instantiation of template class T. STORAGE, if
16974 non-null, is the RID for extern, inline or static. COMPLAIN is
16975 nonzero if this is called from the parser, zero if called recursively,
16976 since the standard is unclear (as detailed below). */
16979 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16984 int previous_instantiation_extern_p = 0;
16986 if (TREE_CODE (t) == TYPE_DECL)
16989 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16991 error ("explicit instantiation of non-template type %qT", t);
16997 if (!COMPLETE_TYPE_P (t))
16999 if (complain & tf_error)
17000 error ("explicit instantiation of %q#T before definition of template",
17005 if (storage != NULL_TREE)
17007 if (!in_system_header)
17009 if (storage == ridpointers[(int) RID_EXTERN])
17011 if (cxx_dialect == cxx98)
17012 pedwarn (input_location, OPT_pedantic,
17013 "ISO C++ 1998 forbids the use of %<extern%> on "
17014 "explicit instantiations");
17017 pedwarn (input_location, OPT_pedantic,
17018 "ISO C++ forbids the use of %qE"
17019 " on explicit instantiations", storage);
17022 if (storage == ridpointers[(int) RID_INLINE])
17024 else if (storage == ridpointers[(int) RID_EXTERN])
17026 else if (storage == ridpointers[(int) RID_STATIC])
17030 error ("storage class %qD applied to template instantiation",
17036 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17038 /* DR 259 [temp.spec].
17040 Both an explicit instantiation and a declaration of an explicit
17041 specialization shall not appear in a program unless the explicit
17042 instantiation follows a declaration of the explicit specialization.
17044 For a given set of template parameters, if an explicit
17045 instantiation of a template appears after a declaration of an
17046 explicit specialization for that template, the explicit
17047 instantiation has no effect. */
17050 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17054 No program shall explicitly instantiate any template more
17057 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17058 instantiation was `extern'. If EXTERN_P then the second is.
17059 These cases are OK. */
17060 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17062 if (!previous_instantiation_extern_p && !extern_p
17063 && (complain & tf_error))
17064 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17066 /* If we've already instantiated the template, just return now. */
17067 if (!CLASSTYPE_INTERFACE_ONLY (t))
17071 check_explicit_instantiation_namespace (TYPE_NAME (t));
17072 mark_class_instantiated (t, extern_p);
17080 /* In contrast to implicit instantiation, where only the
17081 declarations, and not the definitions, of members are
17082 instantiated, we have here:
17086 The explicit instantiation of a class template specialization
17087 implies the instantiation of all of its members not
17088 previously explicitly specialized in the translation unit
17089 containing the explicit instantiation.
17091 Of course, we can't instantiate member template classes, since
17092 we don't have any arguments for them. Note that the standard
17093 is unclear on whether the instantiation of the members are
17094 *explicit* instantiations or not. However, the most natural
17095 interpretation is that it should be an explicit instantiation. */
17098 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17099 if (TREE_CODE (tmp) == FUNCTION_DECL
17100 && DECL_TEMPLATE_INSTANTIATION (tmp))
17101 instantiate_class_member (tmp, extern_p);
17103 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17104 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17105 instantiate_class_member (tmp, extern_p);
17107 if (CLASSTYPE_NESTED_UTDS (t))
17108 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17109 bt_instantiate_type_proc, &storage);
17113 /* Given a function DECL, which is a specialization of TMPL, modify
17114 DECL to be a re-instantiation of TMPL with the same template
17115 arguments. TMPL should be the template into which tsubst'ing
17116 should occur for DECL, not the most general template.
17118 One reason for doing this is a scenario like this:
17121 void f(const T&, int i);
17123 void g() { f(3, 7); }
17126 void f(const T& t, const int i) { }
17128 Note that when the template is first instantiated, with
17129 instantiate_template, the resulting DECL will have no name for the
17130 first parameter, and the wrong type for the second. So, when we go
17131 to instantiate the DECL, we regenerate it. */
17134 regenerate_decl_from_template (tree decl, tree tmpl)
17136 /* The arguments used to instantiate DECL, from the most general
17141 args = DECL_TI_ARGS (decl);
17142 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17144 /* Make sure that we can see identifiers, and compute access
17146 push_access_scope (decl);
17148 if (TREE_CODE (decl) == FUNCTION_DECL)
17156 args_depth = TMPL_ARGS_DEPTH (args);
17157 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17158 if (args_depth > parms_depth)
17159 args = get_innermost_template_args (args, parms_depth);
17161 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17162 args, tf_error, NULL_TREE);
17164 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17167 /* Merge parameter declarations. */
17168 decl_parm = skip_artificial_parms_for (decl,
17169 DECL_ARGUMENTS (decl));
17171 = skip_artificial_parms_for (code_pattern,
17172 DECL_ARGUMENTS (code_pattern));
17173 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17178 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17179 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17180 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17182 parm_type = type_decays_to (parm_type);
17183 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17184 TREE_TYPE (decl_parm) = parm_type;
17185 attributes = DECL_ATTRIBUTES (pattern_parm);
17186 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17188 DECL_ATTRIBUTES (decl_parm) = attributes;
17189 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17191 decl_parm = DECL_CHAIN (decl_parm);
17192 pattern_parm = DECL_CHAIN (pattern_parm);
17194 /* Merge any parameters that match with the function parameter
17196 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17199 tree expanded_types;
17200 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17201 the parameters in this function parameter pack. */
17202 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17203 args, tf_error, NULL_TREE);
17204 len = TREE_VEC_LENGTH (expanded_types);
17205 for (i = 0; i < len; i++)
17210 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17211 /* Rename the parameter to include the index. */
17212 DECL_NAME (decl_parm) =
17213 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17214 parm_type = TREE_VEC_ELT (expanded_types, i);
17215 parm_type = type_decays_to (parm_type);
17216 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17217 TREE_TYPE (decl_parm) = parm_type;
17218 attributes = DECL_ATTRIBUTES (pattern_parm);
17219 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17221 DECL_ATTRIBUTES (decl_parm) = attributes;
17222 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17224 decl_parm = DECL_CHAIN (decl_parm);
17227 /* Merge additional specifiers from the CODE_PATTERN. */
17228 if (DECL_DECLARED_INLINE_P (code_pattern)
17229 && !DECL_DECLARED_INLINE_P (decl))
17230 DECL_DECLARED_INLINE_P (decl) = 1;
17232 else if (TREE_CODE (decl) == VAR_DECL)
17234 DECL_INITIAL (decl) =
17235 tsubst_expr (DECL_INITIAL (code_pattern), args,
17236 tf_error, DECL_TI_TEMPLATE (decl),
17237 /*integral_constant_expression_p=*/false);
17238 if (VAR_HAD_UNKNOWN_BOUND (decl))
17239 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17240 tf_error, DECL_TI_TEMPLATE (decl));
17243 gcc_unreachable ();
17245 pop_access_scope (decl);
17248 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17249 substituted to get DECL. */
17252 template_for_substitution (tree decl)
17254 tree tmpl = DECL_TI_TEMPLATE (decl);
17256 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17257 for the instantiation. This is not always the most general
17258 template. Consider, for example:
17261 struct S { template <class U> void f();
17262 template <> void f<int>(); };
17264 and an instantiation of S<double>::f<int>. We want TD to be the
17265 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17266 while (/* An instantiation cannot have a definition, so we need a
17267 more general template. */
17268 DECL_TEMPLATE_INSTANTIATION (tmpl)
17269 /* We must also deal with friend templates. Given:
17271 template <class T> struct S {
17272 template <class U> friend void f() {};
17275 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17276 so far as the language is concerned, but that's still
17277 where we get the pattern for the instantiation from. On
17278 other hand, if the definition comes outside the class, say:
17280 template <class T> struct S {
17281 template <class U> friend void f();
17283 template <class U> friend void f() {}
17285 we don't need to look any further. That's what the check for
17286 DECL_INITIAL is for. */
17287 || (TREE_CODE (decl) == FUNCTION_DECL
17288 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17289 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17291 /* The present template, TD, should not be a definition. If it
17292 were a definition, we should be using it! Note that we
17293 cannot restructure the loop to just keep going until we find
17294 a template with a definition, since that might go too far if
17295 a specialization was declared, but not defined. */
17296 gcc_assert (TREE_CODE (decl) != VAR_DECL
17297 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17299 /* Fetch the more general template. */
17300 tmpl = DECL_TI_TEMPLATE (tmpl);
17306 /* Returns true if we need to instantiate this template instance even if we
17307 know we aren't going to emit it.. */
17310 always_instantiate_p (tree decl)
17312 /* We always instantiate inline functions so that we can inline them. An
17313 explicit instantiation declaration prohibits implicit instantiation of
17314 non-inline functions. With high levels of optimization, we would
17315 normally inline non-inline functions -- but we're not allowed to do
17316 that for "extern template" functions. Therefore, we check
17317 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17318 return ((TREE_CODE (decl) == FUNCTION_DECL
17319 && DECL_DECLARED_INLINE_P (decl))
17320 /* And we need to instantiate static data members so that
17321 their initializers are available in integral constant
17323 || (TREE_CODE (decl) == VAR_DECL
17324 && decl_maybe_constant_var_p (decl)));
17327 /* Produce the definition of D, a _DECL generated from a template. If
17328 DEFER_OK is nonzero, then we don't have to actually do the
17329 instantiation now; we just have to do it sometime. Normally it is
17330 an error if this is an explicit instantiation but D is undefined.
17331 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17332 explicitly instantiated class template. */
17335 instantiate_decl (tree d, int defer_ok,
17336 bool expl_inst_class_mem_p)
17338 tree tmpl = DECL_TI_TEMPLATE (d);
17345 bool pattern_defined;
17347 location_t saved_loc = input_location;
17350 /* This function should only be used to instantiate templates for
17351 functions and static member variables. */
17352 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17353 || TREE_CODE (d) == VAR_DECL);
17355 /* Variables are never deferred; if instantiation is required, they
17356 are instantiated right away. That allows for better code in the
17357 case that an expression refers to the value of the variable --
17358 if the variable has a constant value the referring expression can
17359 take advantage of that fact. */
17360 if (TREE_CODE (d) == VAR_DECL
17361 || DECL_DECLARED_CONSTEXPR_P (d))
17364 /* Don't instantiate cloned functions. Instead, instantiate the
17365 functions they cloned. */
17366 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17367 d = DECL_CLONED_FUNCTION (d);
17369 if (DECL_TEMPLATE_INSTANTIATED (d)
17370 || DECL_TEMPLATE_SPECIALIZATION (d))
17371 /* D has already been instantiated or explicitly specialized, so
17372 there's nothing for us to do here.
17374 It might seem reasonable to check whether or not D is an explicit
17375 instantiation, and, if so, stop here. But when an explicit
17376 instantiation is deferred until the end of the compilation,
17377 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17378 the instantiation. */
17381 /* Check to see whether we know that this template will be
17382 instantiated in some other file, as with "extern template"
17384 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17386 /* In general, we do not instantiate such templates. */
17387 if (external_p && !always_instantiate_p (d))
17390 gen_tmpl = most_general_template (tmpl);
17391 gen_args = DECL_TI_ARGS (d);
17393 if (tmpl != gen_tmpl)
17394 /* We should already have the extra args. */
17395 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17396 == TMPL_ARGS_DEPTH (gen_args));
17397 /* And what's in the hash table should match D. */
17398 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17399 || spec == NULL_TREE);
17401 /* This needs to happen before any tsubsting. */
17402 if (! push_tinst_level (d))
17405 timevar_push (TV_TEMPLATE_INST);
17407 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
17408 for the instantiation. */
17409 td = template_for_substitution (d);
17410 code_pattern = DECL_TEMPLATE_RESULT (td);
17412 /* We should never be trying to instantiate a member of a class
17413 template or partial specialization. */
17414 gcc_assert (d != code_pattern);
17416 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
17417 || DECL_TEMPLATE_SPECIALIZATION (td))
17418 /* In the case of a friend template whose definition is provided
17419 outside the class, we may have too many arguments. Drop the
17420 ones we don't need. The same is true for specializations. */
17421 args = get_innermost_template_args
17422 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
17426 if (TREE_CODE (d) == FUNCTION_DECL)
17427 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
17428 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
17430 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
17432 /* We may be in the middle of deferred access check. Disable it now. */
17433 push_deferring_access_checks (dk_no_deferred);
17435 /* Unless an explicit instantiation directive has already determined
17436 the linkage of D, remember that a definition is available for
17438 if (pattern_defined
17439 && !DECL_INTERFACE_KNOWN (d)
17440 && !DECL_NOT_REALLY_EXTERN (d))
17441 mark_definable (d);
17443 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
17444 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
17445 input_location = DECL_SOURCE_LOCATION (d);
17447 /* If D is a member of an explicitly instantiated class template,
17448 and no definition is available, treat it like an implicit
17450 if (!pattern_defined && expl_inst_class_mem_p
17451 && DECL_EXPLICIT_INSTANTIATION (d))
17453 /* Leave linkage flags alone on instantiations with anonymous
17455 if (TREE_PUBLIC (d))
17457 DECL_NOT_REALLY_EXTERN (d) = 0;
17458 DECL_INTERFACE_KNOWN (d) = 0;
17460 SET_DECL_IMPLICIT_INSTANTIATION (d);
17463 /* Recheck the substitutions to obtain any warning messages
17464 about ignoring cv qualifiers. Don't do this for artificial decls,
17465 as it breaks the context-sensitive substitution for lambda op(). */
17466 if (!defer_ok && !DECL_ARTIFICIAL (d))
17468 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
17469 tree type = TREE_TYPE (gen);
17471 /* Make sure that we can see identifiers, and compute access
17472 correctly. D is already the target FUNCTION_DECL with the
17474 push_access_scope (d);
17476 if (TREE_CODE (gen) == FUNCTION_DECL)
17478 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
17479 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
17481 /* Don't simply tsubst the function type, as that will give
17482 duplicate warnings about poor parameter qualifications.
17483 The function arguments are the same as the decl_arguments
17484 without the top level cv qualifiers. */
17485 type = TREE_TYPE (type);
17487 tsubst (type, gen_args, tf_warning_or_error, d);
17489 pop_access_scope (d);
17492 /* Defer all other templates, unless we have been explicitly
17493 forbidden from doing so. */
17494 if (/* If there is no definition, we cannot instantiate the
17497 /* If it's OK to postpone instantiation, do so. */
17499 /* If this is a static data member that will be defined
17500 elsewhere, we don't want to instantiate the entire data
17501 member, but we do want to instantiate the initializer so that
17502 we can substitute that elsewhere. */
17503 || (external_p && TREE_CODE (d) == VAR_DECL))
17505 /* The definition of the static data member is now required so
17506 we must substitute the initializer. */
17507 if (TREE_CODE (d) == VAR_DECL
17508 && !DECL_INITIAL (d)
17509 && DECL_INITIAL (code_pattern))
17513 bool const_init = false;
17515 ns = decl_namespace_context (d);
17516 push_nested_namespace (ns);
17517 push_nested_class (DECL_CONTEXT (d));
17518 init = tsubst_expr (DECL_INITIAL (code_pattern),
17520 tf_warning_or_error, NULL_TREE,
17521 /*integral_constant_expression_p=*/false);
17522 /* Make sure the initializer is still constant, in case of
17523 circular dependency (template/instantiate6.C). */
17525 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17526 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
17527 /*asmspec_tree=*/NULL_TREE,
17528 LOOKUP_ONLYCONVERTING);
17529 pop_nested_class ();
17530 pop_nested_namespace (ns);
17533 /* We restore the source position here because it's used by
17534 add_pending_template. */
17535 input_location = saved_loc;
17537 if (at_eof && !pattern_defined
17538 && DECL_EXPLICIT_INSTANTIATION (d)
17539 && DECL_NOT_REALLY_EXTERN (d))
17542 The definition of a non-exported function template, a
17543 non-exported member function template, or a non-exported
17544 member function or static data member of a class template
17545 shall be present in every translation unit in which it is
17546 explicitly instantiated. */
17547 permerror (input_location, "explicit instantiation of %qD "
17548 "but no definition available", d);
17550 /* If we're in unevaluated context, we just wanted to get the
17551 constant value; this isn't an odr use, so don't queue
17552 a full instantiation. */
17553 if (cp_unevaluated_operand != 0)
17555 /* ??? Historically, we have instantiated inline functions, even
17556 when marked as "extern template". */
17557 if (!(external_p && TREE_CODE (d) == VAR_DECL))
17558 add_pending_template (d);
17561 /* Tell the repository that D is available in this translation unit
17562 -- and see if it is supposed to be instantiated here. */
17563 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
17565 /* In a PCH file, despite the fact that the repository hasn't
17566 requested instantiation in the PCH it is still possible that
17567 an instantiation will be required in a file that includes the
17570 add_pending_template (d);
17571 /* Instantiate inline functions so that the inliner can do its
17572 job, even though we'll not be emitting a copy of this
17574 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
17578 need_push = !cfun || !global_bindings_p ();
17580 push_to_top_level ();
17582 /* Mark D as instantiated so that recursive calls to
17583 instantiate_decl do not try to instantiate it again. */
17584 DECL_TEMPLATE_INSTANTIATED (d) = 1;
17586 /* Regenerate the declaration in case the template has been modified
17587 by a subsequent redeclaration. */
17588 regenerate_decl_from_template (d, td);
17590 /* We already set the file and line above. Reset them now in case
17591 they changed as a result of calling regenerate_decl_from_template. */
17592 input_location = DECL_SOURCE_LOCATION (d);
17594 if (TREE_CODE (d) == VAR_DECL)
17597 bool const_init = false;
17599 /* Clear out DECL_RTL; whatever was there before may not be right
17600 since we've reset the type of the declaration. */
17601 SET_DECL_RTL (d, NULL);
17602 DECL_IN_AGGR_P (d) = 0;
17604 /* The initializer is placed in DECL_INITIAL by
17605 regenerate_decl_from_template so we don't need to
17606 push/pop_access_scope again here. Pull it out so that
17607 cp_finish_decl can process it. */
17608 init = DECL_INITIAL (d);
17609 DECL_INITIAL (d) = NULL_TREE;
17610 DECL_INITIALIZED_P (d) = 0;
17612 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
17613 initializer. That function will defer actual emission until
17614 we have a chance to determine linkage. */
17615 DECL_EXTERNAL (d) = 0;
17617 /* Enter the scope of D so that access-checking works correctly. */
17618 push_nested_class (DECL_CONTEXT (d));
17619 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17620 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
17621 pop_nested_class ();
17623 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
17624 synthesize_method (d);
17625 else if (TREE_CODE (d) == FUNCTION_DECL)
17627 htab_t saved_local_specializations;
17632 /* Save away the current list, in case we are instantiating one
17633 template from within the body of another. */
17634 saved_local_specializations = local_specializations;
17636 /* Set up the list of local specializations. */
17637 local_specializations = htab_create (37,
17638 hash_local_specialization,
17639 eq_local_specializations,
17642 /* Set up context. */
17643 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
17645 /* Create substitution entries for the parameters. */
17646 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
17647 tmpl_parm = DECL_ARGUMENTS (subst_decl);
17648 spec_parm = DECL_ARGUMENTS (d);
17649 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
17651 register_local_specialization (spec_parm, tmpl_parm);
17652 spec_parm = skip_artificial_parms_for (d, spec_parm);
17653 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
17655 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17657 register_local_specialization (spec_parm, tmpl_parm);
17658 tmpl_parm = DECL_CHAIN (tmpl_parm);
17659 spec_parm = DECL_CHAIN (spec_parm);
17661 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17663 /* Register the (value) argument pack as a specialization of
17664 TMPL_PARM, then move on. */
17665 tree argpack = make_fnparm_pack (spec_parm);
17666 register_local_specialization (argpack, tmpl_parm);
17667 tmpl_parm = DECL_CHAIN (tmpl_parm);
17668 spec_parm = NULL_TREE;
17670 gcc_assert (!spec_parm);
17672 /* Substitute into the body of the function. */
17673 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
17674 tf_warning_or_error, tmpl,
17675 /*integral_constant_expression_p=*/false);
17677 /* Set the current input_location to the end of the function
17678 so that finish_function knows where we are. */
17679 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17681 /* We don't need the local specializations any more. */
17682 htab_delete (local_specializations);
17683 local_specializations = saved_local_specializations;
17685 /* Finish the function. */
17686 d = finish_function (0);
17687 expand_or_defer_fn (d);
17690 /* We're not deferring instantiation any more. */
17691 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17694 pop_from_top_level ();
17697 input_location = saved_loc;
17698 pop_deferring_access_checks ();
17699 pop_tinst_level ();
17701 timevar_pop (TV_TEMPLATE_INST);
17706 /* Run through the list of templates that we wish we could
17707 instantiate, and instantiate any we can. RETRIES is the
17708 number of times we retry pending template instantiation. */
17711 instantiate_pending_templates (int retries)
17714 location_t saved_loc = input_location;
17716 /* Instantiating templates may trigger vtable generation. This in turn
17717 may require further template instantiations. We place a limit here
17718 to avoid infinite loop. */
17719 if (pending_templates && retries >= max_tinst_depth)
17721 tree decl = pending_templates->tinst->decl;
17723 error ("template instantiation depth exceeds maximum of %d"
17724 " instantiating %q+D, possibly from virtual table generation"
17725 " (use -ftemplate-depth= to increase the maximum)",
17726 max_tinst_depth, decl);
17727 if (TREE_CODE (decl) == FUNCTION_DECL)
17728 /* Pretend that we defined it. */
17729 DECL_INITIAL (decl) = error_mark_node;
17735 struct pending_template **t = &pending_templates;
17736 struct pending_template *last = NULL;
17740 tree instantiation = reopen_tinst_level ((*t)->tinst);
17741 bool complete = false;
17743 if (TYPE_P (instantiation))
17747 if (!COMPLETE_TYPE_P (instantiation))
17749 instantiate_class_template (instantiation);
17750 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17751 for (fn = TYPE_METHODS (instantiation);
17753 fn = TREE_CHAIN (fn))
17754 if (! DECL_ARTIFICIAL (fn))
17755 instantiate_decl (fn,
17757 /*expl_inst_class_mem_p=*/false);
17758 if (COMPLETE_TYPE_P (instantiation))
17762 complete = COMPLETE_TYPE_P (instantiation);
17766 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17767 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17770 = instantiate_decl (instantiation,
17772 /*expl_inst_class_mem_p=*/false);
17773 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17777 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17778 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17782 /* If INSTANTIATION has been instantiated, then we don't
17783 need to consider it again in the future. */
17791 current_tinst_level = NULL;
17793 last_pending_template = last;
17795 while (reconsider);
17797 input_location = saved_loc;
17800 /* Substitute ARGVEC into T, which is a list of initializers for
17801 either base class or a non-static data member. The TREE_PURPOSEs
17802 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17803 instantiate_decl. */
17806 tsubst_initializer_list (tree t, tree argvec)
17808 tree inits = NULL_TREE;
17810 for (; t; t = TREE_CHAIN (t))
17814 tree expanded_bases = NULL_TREE;
17815 tree expanded_arguments = NULL_TREE;
17818 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17823 /* Expand the base class expansion type into separate base
17825 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17826 tf_warning_or_error,
17828 if (expanded_bases == error_mark_node)
17831 /* We'll be building separate TREE_LISTs of arguments for
17833 len = TREE_VEC_LENGTH (expanded_bases);
17834 expanded_arguments = make_tree_vec (len);
17835 for (i = 0; i < len; i++)
17836 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17838 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17839 expand each argument in the TREE_VALUE of t. */
17840 expr = make_node (EXPR_PACK_EXPANSION);
17841 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17842 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17844 if (TREE_VALUE (t) == void_type_node)
17845 /* VOID_TYPE_NODE is used to indicate
17846 value-initialization. */
17848 for (i = 0; i < len; i++)
17849 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17853 /* Substitute parameter packs into each argument in the
17855 in_base_initializer = 1;
17856 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17858 tree expanded_exprs;
17860 /* Expand the argument. */
17861 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17863 = tsubst_pack_expansion (expr, argvec,
17864 tf_warning_or_error,
17866 if (expanded_exprs == error_mark_node)
17869 /* Prepend each of the expanded expressions to the
17870 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17871 for (i = 0; i < len; i++)
17873 TREE_VEC_ELT (expanded_arguments, i) =
17874 tree_cons (NULL_TREE,
17875 TREE_VEC_ELT (expanded_exprs, i),
17876 TREE_VEC_ELT (expanded_arguments, i));
17879 in_base_initializer = 0;
17881 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17882 since we built them backwards. */
17883 for (i = 0; i < len; i++)
17885 TREE_VEC_ELT (expanded_arguments, i) =
17886 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17891 for (i = 0; i < len; ++i)
17893 if (expanded_bases)
17895 decl = TREE_VEC_ELT (expanded_bases, i);
17896 decl = expand_member_init (decl);
17897 init = TREE_VEC_ELT (expanded_arguments, i);
17901 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17902 tf_warning_or_error, NULL_TREE);
17904 decl = expand_member_init (decl);
17905 if (decl && !DECL_P (decl))
17906 in_base_initializer = 1;
17908 init = TREE_VALUE (t);
17909 if (init != void_type_node)
17910 init = tsubst_expr (init, argvec,
17911 tf_warning_or_error, NULL_TREE,
17912 /*integral_constant_expression_p=*/false);
17913 in_base_initializer = 0;
17918 init = build_tree_list (decl, init);
17919 TREE_CHAIN (init) = inits;
17927 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17930 set_current_access_from_decl (tree decl)
17932 if (TREE_PRIVATE (decl))
17933 current_access_specifier = access_private_node;
17934 else if (TREE_PROTECTED (decl))
17935 current_access_specifier = access_protected_node;
17937 current_access_specifier = access_public_node;
17940 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17941 is the instantiation (which should have been created with
17942 start_enum) and ARGS are the template arguments to use. */
17945 tsubst_enum (tree tag, tree newtag, tree args)
17949 if (SCOPED_ENUM_P (newtag))
17950 begin_scope (sk_scoped_enum, newtag);
17952 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17957 decl = TREE_VALUE (e);
17958 /* Note that in a template enum, the TREE_VALUE is the
17959 CONST_DECL, not the corresponding INTEGER_CST. */
17960 value = tsubst_expr (DECL_INITIAL (decl),
17961 args, tf_warning_or_error, NULL_TREE,
17962 /*integral_constant_expression_p=*/true);
17964 /* Give this enumeration constant the correct access. */
17965 set_current_access_from_decl (decl);
17967 /* Actually build the enumerator itself. */
17969 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
17972 if (SCOPED_ENUM_P (newtag))
17975 finish_enum_value_list (newtag);
17976 finish_enum (newtag);
17978 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17979 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17982 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17983 its type -- but without substituting the innermost set of template
17984 arguments. So, innermost set of template parameters will appear in
17988 get_mostly_instantiated_function_type (tree decl)
17996 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17997 targs = DECL_TI_ARGS (decl);
17998 tparms = DECL_TEMPLATE_PARMS (tmpl);
17999 parm_depth = TMPL_PARMS_DEPTH (tparms);
18001 /* There should be as many levels of arguments as there are levels
18003 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18005 fn_type = TREE_TYPE (tmpl);
18007 if (parm_depth == 1)
18008 /* No substitution is necessary. */
18015 /* Replace the innermost level of the TARGS with NULL_TREEs to
18016 let tsubst know not to substitute for those parameters. */
18017 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18018 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18019 SET_TMPL_ARGS_LEVEL (partial_args, i,
18020 TMPL_ARGS_LEVEL (targs, i));
18021 SET_TMPL_ARGS_LEVEL (partial_args,
18022 TMPL_ARGS_DEPTH (targs),
18023 make_tree_vec (DECL_NTPARMS (tmpl)));
18025 /* Make sure that we can see identifiers, and compute access
18027 push_access_scope (decl);
18029 ++processing_template_decl;
18030 /* Now, do the (partial) substitution to figure out the
18031 appropriate function type. */
18032 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
18033 --processing_template_decl;
18035 /* Substitute into the template parameters to obtain the real
18036 innermost set of parameters. This step is important if the
18037 innermost set of template parameters contains value
18038 parameters whose types depend on outer template parameters. */
18039 TREE_VEC_LENGTH (partial_args)--;
18040 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
18042 pop_access_scope (decl);
18048 /* Return truthvalue if we're processing a template different from
18049 the last one involved in diagnostics. */
18051 problematic_instantiation_changed (void)
18053 return last_template_error_tick != tinst_level_tick;
18056 /* Remember current template involved in diagnostics. */
18058 record_last_problematic_instantiation (void)
18060 last_template_error_tick = tinst_level_tick;
18063 struct tinst_level *
18064 current_instantiation (void)
18066 return current_tinst_level;
18069 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18070 type. Return zero for ok, nonzero for disallowed. Issue error and
18071 warning messages under control of COMPLAIN. */
18074 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18076 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18078 else if (POINTER_TYPE_P (type))
18080 else if (TYPE_PTR_TO_MEMBER_P (type))
18082 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18084 else if (TREE_CODE (type) == TYPENAME_TYPE)
18086 else if (TREE_CODE (type) == DECLTYPE_TYPE)
18089 if (complain & tf_error)
18090 error ("%q#T is not a valid type for a template constant parameter", type);
18094 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18095 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18098 dependent_type_p_r (tree type)
18104 A type is dependent if it is:
18106 -- a template parameter. Template template parameters are types
18107 for us (since TYPE_P holds true for them) so we handle
18109 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18110 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18112 /* -- a qualified-id with a nested-name-specifier which contains a
18113 class-name that names a dependent type or whose unqualified-id
18114 names a dependent type. */
18115 if (TREE_CODE (type) == TYPENAME_TYPE)
18117 /* -- a cv-qualified type where the cv-unqualified type is
18119 type = TYPE_MAIN_VARIANT (type);
18120 /* -- a compound type constructed from any dependent type. */
18121 if (TYPE_PTR_TO_MEMBER_P (type))
18122 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18123 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18125 else if (TREE_CODE (type) == POINTER_TYPE
18126 || TREE_CODE (type) == REFERENCE_TYPE)
18127 return dependent_type_p (TREE_TYPE (type));
18128 else if (TREE_CODE (type) == FUNCTION_TYPE
18129 || TREE_CODE (type) == METHOD_TYPE)
18133 if (dependent_type_p (TREE_TYPE (type)))
18135 for (arg_type = TYPE_ARG_TYPES (type);
18137 arg_type = TREE_CHAIN (arg_type))
18138 if (dependent_type_p (TREE_VALUE (arg_type)))
18142 /* -- an array type constructed from any dependent type or whose
18143 size is specified by a constant expression that is
18146 We checked for type- and value-dependence of the bounds in
18147 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18148 if (TREE_CODE (type) == ARRAY_TYPE)
18150 if (TYPE_DOMAIN (type)
18151 && dependent_type_p (TYPE_DOMAIN (type)))
18153 return dependent_type_p (TREE_TYPE (type));
18156 /* -- a template-id in which either the template name is a template
18158 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18160 /* ... or any of the template arguments is a dependent type or
18161 an expression that is type-dependent or value-dependent. */
18162 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18163 && (any_dependent_template_arguments_p
18164 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18167 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18168 dependent; if the argument of the `typeof' expression is not
18169 type-dependent, then it should already been have resolved. */
18170 if (TREE_CODE (type) == TYPEOF_TYPE
18171 || TREE_CODE (type) == DECLTYPE_TYPE
18172 || TREE_CODE (type) == UNDERLYING_TYPE)
18175 /* A template argument pack is dependent if any of its packed
18177 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18179 tree args = ARGUMENT_PACK_ARGS (type);
18180 int i, len = TREE_VEC_LENGTH (args);
18181 for (i = 0; i < len; ++i)
18182 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18186 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18187 be template parameters. */
18188 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18191 /* The standard does not specifically mention types that are local
18192 to template functions or local classes, but they should be
18193 considered dependent too. For example:
18195 template <int I> void f() {
18200 The size of `E' cannot be known until the value of `I' has been
18201 determined. Therefore, `E' must be considered dependent. */
18202 scope = TYPE_CONTEXT (type);
18203 if (scope && TYPE_P (scope))
18204 return dependent_type_p (scope);
18205 /* Don't use type_dependent_expression_p here, as it can lead
18206 to infinite recursion trying to determine whether a lambda
18207 nested in a lambda is dependent (c++/47687). */
18208 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
18209 && DECL_LANG_SPECIFIC (scope)
18210 && DECL_TEMPLATE_INFO (scope)
18211 && (any_dependent_template_arguments_p
18212 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
18215 /* Other types are non-dependent. */
18219 /* Returns TRUE if TYPE is dependent, in the sense of
18220 [temp.dep.type]. Note that a NULL type is considered dependent. */
18223 dependent_type_p (tree type)
18225 /* If there are no template parameters in scope, then there can't be
18226 any dependent types. */
18227 if (!processing_template_decl)
18229 /* If we are not processing a template, then nobody should be
18230 providing us with a dependent type. */
18232 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18236 /* If the type is NULL, we have not computed a type for the entity
18237 in question; in that case, the type is dependent. */
18241 /* Erroneous types can be considered non-dependent. */
18242 if (type == error_mark_node)
18245 /* If we have not already computed the appropriate value for TYPE,
18247 if (!TYPE_DEPENDENT_P_VALID (type))
18249 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18250 TYPE_DEPENDENT_P_VALID (type) = 1;
18253 return TYPE_DEPENDENT_P (type);
18256 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18257 lookup. In other words, a dependent type that is not the current
18261 dependent_scope_p (tree scope)
18263 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18264 && !currently_open_class (scope));
18267 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18268 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18271 /* Note that this predicate is not appropriate for general expressions;
18272 only constant expressions (that satisfy potential_constant_expression)
18273 can be tested for value dependence.
18275 We should really also have a predicate for "instantiation-dependent".
18277 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18278 (what about instantiation-dependent constant-expressions?)
18279 is_late_template_attribute: defer if instantiation-dependent.
18280 compute_array_index_type: proceed if constant and not t- or v-dependent
18281 if instantiation-dependent, need to remember full expression
18282 uses_template_parms: FIXME - need to audit callers
18283 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18284 dependent_type_p [array_type]: dependent if index type is dependent
18286 static_assert - instantiation-dependent */
18289 value_dependent_expression_p (tree expression)
18291 if (!processing_template_decl)
18294 /* A name declared with a dependent type. */
18295 if (DECL_P (expression) && type_dependent_expression_p (expression))
18298 switch (TREE_CODE (expression))
18300 case IDENTIFIER_NODE:
18301 /* A name that has not been looked up -- must be dependent. */
18304 case TEMPLATE_PARM_INDEX:
18305 /* A non-type template parm. */
18309 /* A non-type template parm. */
18310 if (DECL_TEMPLATE_PARM_P (expression))
18312 return value_dependent_expression_p (DECL_INITIAL (expression));
18315 /* A constant with literal type and is initialized
18316 with an expression that is value-dependent. */
18317 if (DECL_INITIAL (expression)
18318 && decl_constant_var_p (expression)
18319 && value_dependent_expression_p (DECL_INITIAL (expression)))
18323 case DYNAMIC_CAST_EXPR:
18324 case STATIC_CAST_EXPR:
18325 case CONST_CAST_EXPR:
18326 case REINTERPRET_CAST_EXPR:
18328 /* These expressions are value-dependent if the type to which
18329 the cast occurs is dependent or the expression being casted
18330 is value-dependent. */
18332 tree type = TREE_TYPE (expression);
18334 if (dependent_type_p (type))
18337 /* A functional cast has a list of operands. */
18338 expression = TREE_OPERAND (expression, 0);
18341 /* If there are no operands, it must be an expression such
18342 as "int()". This should not happen for aggregate types
18343 because it would form non-constant expressions. */
18344 gcc_assert (cxx_dialect >= cxx0x
18345 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18350 if (TREE_CODE (expression) == TREE_LIST)
18351 return any_value_dependent_elements_p (expression);
18353 return value_dependent_expression_p (expression);
18359 /* A `sizeof' expression is value-dependent if the operand is
18360 type-dependent or is a pack expansion. */
18361 expression = TREE_OPERAND (expression, 0);
18362 if (PACK_EXPANSION_P (expression))
18364 else if (TYPE_P (expression))
18365 return dependent_type_p (expression);
18366 return type_dependent_expression_p (expression);
18368 case AT_ENCODE_EXPR:
18369 /* An 'encode' expression is value-dependent if the operand is
18371 expression = TREE_OPERAND (expression, 0);
18372 return dependent_type_p (expression);
18374 case NOEXCEPT_EXPR:
18375 expression = TREE_OPERAND (expression, 0);
18376 return type_dependent_expression_p (expression);
18380 tree name = TREE_OPERAND (expression, 1);
18381 return value_dependent_expression_p (name);
18384 case COMPONENT_REF:
18385 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18386 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18388 case NONTYPE_ARGUMENT_PACK:
18389 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18390 is value-dependent. */
18392 tree values = ARGUMENT_PACK_ARGS (expression);
18393 int i, len = TREE_VEC_LENGTH (values);
18395 for (i = 0; i < len; ++i)
18396 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
18404 tree type2 = TRAIT_EXPR_TYPE2 (expression);
18405 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
18406 || (type2 ? dependent_type_p (type2) : false));
18410 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18411 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
18414 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18415 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
18419 tree op = TREE_OPERAND (expression, 0);
18420 return (value_dependent_expression_p (op)
18421 || has_value_dependent_address (op));
18426 tree fn = get_callee_fndecl (expression);
18428 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
18430 nargs = call_expr_nargs (expression);
18431 for (i = 0; i < nargs; ++i)
18433 tree op = CALL_EXPR_ARG (expression, i);
18434 /* In a call to a constexpr member function, look through the
18435 implicit ADDR_EXPR on the object argument so that it doesn't
18436 cause the call to be considered value-dependent. We also
18437 look through it in potential_constant_expression. */
18438 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
18439 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
18440 && TREE_CODE (op) == ADDR_EXPR)
18441 op = TREE_OPERAND (op, 0);
18442 if (value_dependent_expression_p (op))
18448 case TEMPLATE_ID_EXPR:
18449 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
18451 return type_dependent_expression_p (expression);
18457 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
18458 if (value_dependent_expression_p (val))
18464 /* A constant expression is value-dependent if any subexpression is
18465 value-dependent. */
18466 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
18468 case tcc_reference:
18470 case tcc_comparison:
18472 case tcc_expression:
18475 int i, len = cp_tree_operand_length (expression);
18477 for (i = 0; i < len; i++)
18479 tree t = TREE_OPERAND (expression, i);
18481 /* In some cases, some of the operands may be missing.l
18482 (For example, in the case of PREDECREMENT_EXPR, the
18483 amount to increment by may be missing.) That doesn't
18484 make the expression dependent. */
18485 if (t && value_dependent_expression_p (t))
18496 /* The expression is not value-dependent. */
18500 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
18501 [temp.dep.expr]. Note that an expression with no type is
18502 considered dependent. Other parts of the compiler arrange for an
18503 expression with type-dependent subexpressions to have no type, so
18504 this function doesn't have to be fully recursive. */
18507 type_dependent_expression_p (tree expression)
18509 if (!processing_template_decl)
18512 if (expression == error_mark_node)
18515 /* An unresolved name is always dependent. */
18516 if (TREE_CODE (expression) == IDENTIFIER_NODE
18517 || TREE_CODE (expression) == USING_DECL)
18520 /* Some expression forms are never type-dependent. */
18521 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
18522 || TREE_CODE (expression) == SIZEOF_EXPR
18523 || TREE_CODE (expression) == ALIGNOF_EXPR
18524 || TREE_CODE (expression) == AT_ENCODE_EXPR
18525 || TREE_CODE (expression) == NOEXCEPT_EXPR
18526 || TREE_CODE (expression) == TRAIT_EXPR
18527 || TREE_CODE (expression) == TYPEID_EXPR
18528 || TREE_CODE (expression) == DELETE_EXPR
18529 || TREE_CODE (expression) == VEC_DELETE_EXPR
18530 || TREE_CODE (expression) == THROW_EXPR)
18533 /* The types of these expressions depends only on the type to which
18534 the cast occurs. */
18535 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
18536 || TREE_CODE (expression) == STATIC_CAST_EXPR
18537 || TREE_CODE (expression) == CONST_CAST_EXPR
18538 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
18539 || TREE_CODE (expression) == CAST_EXPR)
18540 return dependent_type_p (TREE_TYPE (expression));
18542 /* The types of these expressions depends only on the type created
18543 by the expression. */
18544 if (TREE_CODE (expression) == NEW_EXPR
18545 || TREE_CODE (expression) == VEC_NEW_EXPR)
18547 /* For NEW_EXPR tree nodes created inside a template, either
18548 the object type itself or a TREE_LIST may appear as the
18550 tree type = TREE_OPERAND (expression, 1);
18551 if (TREE_CODE (type) == TREE_LIST)
18552 /* This is an array type. We need to check array dimensions
18554 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
18555 || value_dependent_expression_p
18556 (TREE_OPERAND (TREE_VALUE (type), 1));
18558 return dependent_type_p (type);
18561 if (TREE_CODE (expression) == SCOPE_REF)
18563 tree scope = TREE_OPERAND (expression, 0);
18564 tree name = TREE_OPERAND (expression, 1);
18566 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
18567 contains an identifier associated by name lookup with one or more
18568 declarations declared with a dependent type, or...a
18569 nested-name-specifier or qualified-id that names a member of an
18570 unknown specialization. */
18571 return (type_dependent_expression_p (name)
18572 || dependent_scope_p (scope));
18575 if (TREE_CODE (expression) == FUNCTION_DECL
18576 && DECL_LANG_SPECIFIC (expression)
18577 && DECL_TEMPLATE_INFO (expression)
18578 && (any_dependent_template_arguments_p
18579 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
18582 if (TREE_CODE (expression) == TEMPLATE_DECL
18583 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
18586 if (TREE_CODE (expression) == STMT_EXPR)
18587 expression = stmt_expr_value_expr (expression);
18589 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
18594 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
18596 if (type_dependent_expression_p (elt))
18602 /* A static data member of the current instantiation with incomplete
18603 array type is type-dependent, as the definition and specializations
18604 can have different bounds. */
18605 if (TREE_CODE (expression) == VAR_DECL
18606 && DECL_CLASS_SCOPE_P (expression)
18607 && dependent_type_p (DECL_CONTEXT (expression))
18608 && VAR_HAD_UNKNOWN_BOUND (expression))
18611 if (TREE_TYPE (expression) == unknown_type_node)
18613 if (TREE_CODE (expression) == ADDR_EXPR)
18614 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
18615 if (TREE_CODE (expression) == COMPONENT_REF
18616 || TREE_CODE (expression) == OFFSET_REF)
18618 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
18620 expression = TREE_OPERAND (expression, 1);
18621 if (TREE_CODE (expression) == IDENTIFIER_NODE)
18624 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
18625 if (TREE_CODE (expression) == SCOPE_REF)
18628 if (TREE_CODE (expression) == BASELINK)
18629 expression = BASELINK_FUNCTIONS (expression);
18631 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
18633 if (any_dependent_template_arguments_p
18634 (TREE_OPERAND (expression, 1)))
18636 expression = TREE_OPERAND (expression, 0);
18638 gcc_assert (TREE_CODE (expression) == OVERLOAD
18639 || TREE_CODE (expression) == FUNCTION_DECL);
18643 if (type_dependent_expression_p (OVL_CURRENT (expression)))
18645 expression = OVL_NEXT (expression);
18650 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
18652 return (dependent_type_p (TREE_TYPE (expression)));
18655 /* Like type_dependent_expression_p, but it also works while not processing
18656 a template definition, i.e. during substitution or mangling. */
18659 type_dependent_expression_p_push (tree expr)
18662 ++processing_template_decl;
18663 b = type_dependent_expression_p (expr);
18664 --processing_template_decl;
18668 /* Returns TRUE if ARGS contains a type-dependent expression. */
18671 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
18676 FOR_EACH_VEC_ELT (tree, args, i, arg)
18678 if (type_dependent_expression_p (arg))
18684 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18685 expressions) contains any type-dependent expressions. */
18688 any_type_dependent_elements_p (const_tree list)
18690 for (; list; list = TREE_CHAIN (list))
18691 if (value_dependent_expression_p (TREE_VALUE (list)))
18697 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18698 expressions) contains any value-dependent expressions. */
18701 any_value_dependent_elements_p (const_tree list)
18703 for (; list; list = TREE_CHAIN (list))
18704 if (value_dependent_expression_p (TREE_VALUE (list)))
18710 /* Returns TRUE if the ARG (a template argument) is dependent. */
18713 dependent_template_arg_p (tree arg)
18715 if (!processing_template_decl)
18718 /* Assume a template argument that was wrongly written by the user
18719 is dependent. This is consistent with what
18720 any_dependent_template_arguments_p [that calls this function]
18722 if (arg == error_mark_node)
18725 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
18726 arg = ARGUMENT_PACK_SELECT_ARG (arg);
18728 if (TREE_CODE (arg) == TEMPLATE_DECL
18729 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18730 return dependent_template_p (arg);
18731 else if (ARGUMENT_PACK_P (arg))
18733 tree args = ARGUMENT_PACK_ARGS (arg);
18734 int i, len = TREE_VEC_LENGTH (args);
18735 for (i = 0; i < len; ++i)
18737 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18743 else if (TYPE_P (arg))
18744 return dependent_type_p (arg);
18746 return (type_dependent_expression_p (arg)
18747 || value_dependent_expression_p (arg));
18750 /* Returns true if ARGS (a collection of template arguments) contains
18751 any types that require structural equality testing. */
18754 any_template_arguments_need_structural_equality_p (tree args)
18761 if (args == error_mark_node)
18764 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18766 tree level = TMPL_ARGS_LEVEL (args, i + 1);
18767 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18769 tree arg = TREE_VEC_ELT (level, j);
18770 tree packed_args = NULL_TREE;
18773 if (ARGUMENT_PACK_P (arg))
18775 /* Look inside the argument pack. */
18776 packed_args = ARGUMENT_PACK_ARGS (arg);
18777 len = TREE_VEC_LENGTH (packed_args);
18780 for (k = 0; k < len; ++k)
18783 arg = TREE_VEC_ELT (packed_args, k);
18785 if (error_operand_p (arg))
18787 else if (TREE_CODE (arg) == TEMPLATE_DECL
18788 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18790 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18792 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18793 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18802 /* Returns true if ARGS (a collection of template arguments) contains
18803 any dependent arguments. */
18806 any_dependent_template_arguments_p (const_tree args)
18813 if (args == error_mark_node)
18816 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18818 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18819 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18820 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18827 /* Returns TRUE if the template TMPL is dependent. */
18830 dependent_template_p (tree tmpl)
18832 if (TREE_CODE (tmpl) == OVERLOAD)
18836 if (dependent_template_p (OVL_CURRENT (tmpl)))
18838 tmpl = OVL_NEXT (tmpl);
18843 /* Template template parameters are dependent. */
18844 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18845 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18847 /* So are names that have not been looked up. */
18848 if (TREE_CODE (tmpl) == SCOPE_REF
18849 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18851 /* So are member templates of dependent classes. */
18852 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18853 return dependent_type_p (DECL_CONTEXT (tmpl));
18857 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18860 dependent_template_id_p (tree tmpl, tree args)
18862 return (dependent_template_p (tmpl)
18863 || any_dependent_template_arguments_p (args));
18866 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18870 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18874 if (!processing_template_decl)
18877 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18879 tree decl = TREE_VEC_ELT (declv, i);
18880 tree init = TREE_VEC_ELT (initv, i);
18881 tree cond = TREE_VEC_ELT (condv, i);
18882 tree incr = TREE_VEC_ELT (incrv, i);
18884 if (type_dependent_expression_p (decl))
18887 if (init && type_dependent_expression_p (init))
18890 if (type_dependent_expression_p (cond))
18893 if (COMPARISON_CLASS_P (cond)
18894 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18895 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18898 if (TREE_CODE (incr) == MODOP_EXPR)
18900 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18901 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18904 else if (type_dependent_expression_p (incr))
18906 else if (TREE_CODE (incr) == MODIFY_EXPR)
18908 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18910 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
18912 tree t = TREE_OPERAND (incr, 1);
18913 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
18914 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
18923 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
18924 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
18925 no such TYPE can be found. Note that this function peers inside
18926 uninstantiated templates and therefore should be used only in
18927 extremely limited situations. ONLY_CURRENT_P restricts this
18928 peering to the currently open classes hierarchy (which is required
18929 when comparing types). */
18932 resolve_typename_type (tree type, bool only_current_p)
18941 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
18943 scope = TYPE_CONTEXT (type);
18944 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
18945 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
18946 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
18947 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
18948 identifier of the TYPENAME_TYPE anymore.
18949 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
18950 TYPENAME_TYPE instead, we avoid messing up with a possible
18951 typedef variant case. */
18952 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
18954 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
18955 it first before we can figure out what NAME refers to. */
18956 if (TREE_CODE (scope) == TYPENAME_TYPE)
18957 scope = resolve_typename_type (scope, only_current_p);
18958 /* If we don't know what SCOPE refers to, then we cannot resolve the
18960 if (TREE_CODE (scope) == TYPENAME_TYPE)
18962 /* If the SCOPE is a template type parameter, we have no way of
18963 resolving the name. */
18964 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
18966 /* If the SCOPE is not the current instantiation, there's no reason
18967 to look inside it. */
18968 if (only_current_p && !currently_open_class (scope))
18970 /* If this is a typedef, we don't want to look inside (c++/11987). */
18971 if (typedef_variant_p (type))
18973 /* If SCOPE isn't the template itself, it will not have a valid
18974 TYPE_FIELDS list. */
18975 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
18976 /* scope is either the template itself or a compatible instantiation
18977 like X<T>, so look up the name in the original template. */
18978 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
18980 /* scope is a partial instantiation, so we can't do the lookup or we
18981 will lose the template arguments. */
18983 /* Enter the SCOPE so that name lookup will be resolved as if we
18984 were in the class definition. In particular, SCOPE will no
18985 longer be considered a dependent type. */
18986 pushed_scope = push_scope (scope);
18987 /* Look up the declaration. */
18988 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
18990 result = NULL_TREE;
18992 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
18993 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
18996 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
18997 && TREE_CODE (decl) == TYPE_DECL)
18999 result = TREE_TYPE (decl);
19000 if (result == error_mark_node)
19001 result = NULL_TREE;
19003 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19004 && DECL_CLASS_TEMPLATE_P (decl))
19008 /* Obtain the template and the arguments. */
19009 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19010 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19011 /* Instantiate the template. */
19012 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
19013 /*entering_scope=*/0,
19014 tf_error | tf_user);
19015 if (result == error_mark_node)
19016 result = NULL_TREE;
19019 /* Leave the SCOPE. */
19021 pop_scope (pushed_scope);
19023 /* If we failed to resolve it, return the original typename. */
19027 /* If lookup found a typename type, resolve that too. */
19028 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
19030 /* Ill-formed programs can cause infinite recursion here, so we
19031 must catch that. */
19032 TYPENAME_IS_RESOLVING_P (type) = 1;
19033 result = resolve_typename_type (result, only_current_p);
19034 TYPENAME_IS_RESOLVING_P (type) = 0;
19037 /* Qualify the resulting type. */
19038 quals = cp_type_quals (type);
19040 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
19045 /* EXPR is an expression which is not type-dependent. Return a proxy
19046 for EXPR that can be used to compute the types of larger
19047 expressions containing EXPR. */
19050 build_non_dependent_expr (tree expr)
19054 #ifdef ENABLE_CHECKING
19055 /* Try to get a constant value for all non-type-dependent expressions in
19056 order to expose bugs in *_dependent_expression_p and constexpr. */
19057 if (cxx_dialect >= cxx0x)
19058 maybe_constant_value (fold_non_dependent_expr (expr));
19061 /* Preserve OVERLOADs; the functions must be available to resolve
19064 if (TREE_CODE (inner_expr) == STMT_EXPR)
19065 inner_expr = stmt_expr_value_expr (inner_expr);
19066 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19067 inner_expr = TREE_OPERAND (inner_expr, 0);
19068 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19069 inner_expr = TREE_OPERAND (inner_expr, 1);
19070 if (is_overloaded_fn (inner_expr)
19071 || TREE_CODE (inner_expr) == OFFSET_REF)
19073 /* There is no need to return a proxy for a variable. */
19074 if (TREE_CODE (expr) == VAR_DECL)
19076 /* Preserve string constants; conversions from string constants to
19077 "char *" are allowed, even though normally a "const char *"
19078 cannot be used to initialize a "char *". */
19079 if (TREE_CODE (expr) == STRING_CST)
19081 /* Preserve arithmetic constants, as an optimization -- there is no
19082 reason to create a new node. */
19083 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19085 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19086 There is at least one place where we want to know that a
19087 particular expression is a throw-expression: when checking a ?:
19088 expression, there are special rules if the second or third
19089 argument is a throw-expression. */
19090 if (TREE_CODE (expr) == THROW_EXPR)
19093 if (TREE_CODE (expr) == COND_EXPR)
19094 return build3 (COND_EXPR,
19096 TREE_OPERAND (expr, 0),
19097 (TREE_OPERAND (expr, 1)
19098 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19099 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19100 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19101 if (TREE_CODE (expr) == COMPOUND_EXPR
19102 && !COMPOUND_EXPR_OVERLOADED (expr))
19103 return build2 (COMPOUND_EXPR,
19105 TREE_OPERAND (expr, 0),
19106 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19108 /* If the type is unknown, it can't really be non-dependent */
19109 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19111 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19112 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19115 /* ARGS is a vector of expressions as arguments to a function call.
19116 Replace the arguments with equivalent non-dependent expressions.
19117 This modifies ARGS in place. */
19120 make_args_non_dependent (VEC(tree,gc) *args)
19125 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19127 tree newarg = build_non_dependent_expr (arg);
19129 VEC_replace (tree, args, ix, newarg);
19133 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19134 with a level one deeper than the actual template parms. */
19139 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19140 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19141 TYPE_DECL, get_identifier ("auto"), au);
19142 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19143 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19144 (0, processing_template_decl + 1, processing_template_decl + 1,
19145 0, TYPE_NAME (au), NULL_TREE);
19146 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19147 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19148 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19153 /* Given type ARG, return std::initializer_list<ARG>. */
19158 tree std_init_list = namespace_binding
19159 (get_identifier ("initializer_list"), std_node);
19161 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19163 error ("deducing from brace-enclosed initializer list requires "
19164 "#include <initializer_list>");
19165 return error_mark_node;
19167 argvec = make_tree_vec (1);
19168 TREE_VEC_ELT (argvec, 0) = arg;
19169 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19170 NULL_TREE, 0, tf_warning_or_error);
19173 /* Replace auto in TYPE with std::initializer_list<auto>. */
19176 listify_autos (tree type, tree auto_node)
19178 tree init_auto = listify (auto_node);
19179 tree argvec = make_tree_vec (1);
19180 TREE_VEC_ELT (argvec, 0) = init_auto;
19181 if (processing_template_decl)
19182 argvec = add_to_template_args (current_template_args (), argvec);
19183 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19186 /* walk_tree helper for do_auto_deduction. */
19189 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19192 /* Is this a variable with the type we're looking for? */
19194 && TREE_TYPE (*tp) == type)
19200 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19201 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19204 do_auto_deduction (tree type, tree init, tree auto_node)
19206 tree parms, tparms, targs;
19211 /* The name of the object being declared shall not appear in the
19212 initializer expression. */
19213 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19216 error ("variable %q#D with %<auto%> type used in its own "
19217 "initializer", decl);
19218 return error_mark_node;
19221 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19222 with either a new invented type template parameter U or, if the
19223 initializer is a braced-init-list (8.5.4), with
19224 std::initializer_list<U>. */
19225 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19226 type = listify_autos (type, auto_node);
19228 init = resolve_nondeduced_context (init);
19230 parms = build_tree_list (NULL_TREE, type);
19232 tparms = make_tree_vec (1);
19233 targs = make_tree_vec (1);
19234 TREE_VEC_ELT (tparms, 0)
19235 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19236 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19237 DEDUCE_CALL, LOOKUP_NORMAL);
19240 if (type && type != error_mark_node)
19241 /* If type is error_mark_node a diagnostic must have been
19242 emitted by now. Also, having a mention to '<type error>'
19243 in the diagnostic is not really useful to the user. */
19244 error ("unable to deduce %qT from %qE", type, init);
19245 return error_mark_node;
19248 /* If the list of declarators contains more than one declarator, the type
19249 of each declared variable is determined as described above. If the
19250 type deduced for the template parameter U is not the same in each
19251 deduction, the program is ill-formed. */
19252 if (TREE_TYPE (auto_node)
19253 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19255 error ("inconsistent deduction for %qT: %qT and then %qT",
19256 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19257 return error_mark_node;
19259 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19261 if (processing_template_decl)
19262 targs = add_to_template_args (current_template_args (), targs);
19263 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19266 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19270 splice_late_return_type (tree type, tree late_return_type)
19274 if (late_return_type == NULL_TREE)
19276 argvec = make_tree_vec (1);
19277 TREE_VEC_ELT (argvec, 0) = late_return_type;
19278 if (processing_template_parmlist)
19279 /* For a late-specified return type in a template type-parameter, we
19280 need to add a dummy argument level for its parmlist. */
19281 argvec = add_to_template_args
19282 (make_tree_vec (processing_template_parmlist), argvec);
19283 if (current_template_parms)
19284 argvec = add_to_template_args (current_template_args (), argvec);
19285 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19288 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19291 is_auto (const_tree type)
19293 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19294 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
19300 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
19301 appear as a type-specifier for the declaration in question, we don't
19302 have to look through the whole type. */
19305 type_uses_auto (tree type)
19307 enum tree_code code;
19308 if (is_auto (type))
19311 code = TREE_CODE (type);
19313 if (code == POINTER_TYPE || code == REFERENCE_TYPE
19314 || code == OFFSET_TYPE || code == FUNCTION_TYPE
19315 || code == METHOD_TYPE || code == ARRAY_TYPE)
19316 return type_uses_auto (TREE_TYPE (type));
19318 if (TYPE_PTRMEMFUNC_P (type))
19319 return type_uses_auto (TREE_TYPE (TREE_TYPE
19320 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
19325 /* For a given template T, return the vector of typedefs referenced
19326 in T for which access check is needed at T instantiation time.
19327 T is either a FUNCTION_DECL or a RECORD_TYPE.
19328 Those typedefs were added to T by the function
19329 append_type_to_template_for_access_check. */
19331 VEC(qualified_typedef_usage_t,gc)*
19332 get_types_needing_access_check (tree t)
19335 VEC(qualified_typedef_usage_t,gc) *result = NULL;
19337 if (!t || t == error_mark_node)
19340 if (!(ti = get_template_info (t)))
19343 if (CLASS_TYPE_P (t)
19344 || TREE_CODE (t) == FUNCTION_DECL)
19346 if (!TI_TEMPLATE (ti))
19349 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19355 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19356 tied to T. That list of typedefs will be access checked at
19357 T instantiation time.
19358 T is either a FUNCTION_DECL or a RECORD_TYPE.
19359 TYPE_DECL is a TYPE_DECL node representing a typedef.
19360 SCOPE is the scope through which TYPE_DECL is accessed.
19361 LOCATION is the location of the usage point of TYPE_DECL.
19363 This function is a subroutine of
19364 append_type_to_template_for_access_check. */
19367 append_type_to_template_for_access_check_1 (tree t,
19370 location_t location)
19372 qualified_typedef_usage_t typedef_usage;
19375 if (!t || t == error_mark_node)
19378 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19379 || CLASS_TYPE_P (t))
19381 && TREE_CODE (type_decl) == TYPE_DECL
19384 if (!(ti = get_template_info (t)))
19387 gcc_assert (TI_TEMPLATE (ti));
19389 typedef_usage.typedef_decl = type_decl;
19390 typedef_usage.context = scope;
19391 typedef_usage.locus = location;
19393 VEC_safe_push (qualified_typedef_usage_t, gc,
19394 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
19398 /* Append TYPE_DECL to the template TEMPL.
19399 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
19400 At TEMPL instanciation time, TYPE_DECL will be checked to see
19401 if it can be accessed through SCOPE.
19402 LOCATION is the location of the usage point of TYPE_DECL.
19404 e.g. consider the following code snippet:
19411 template<class U> struct S
19413 C::myint mi; // <-- usage point of the typedef C::myint
19418 At S<char> instantiation time, we need to check the access of C::myint
19419 In other words, we need to check the access of the myint typedef through
19420 the C scope. For that purpose, this function will add the myint typedef
19421 and the scope C through which its being accessed to a list of typedefs
19422 tied to the template S. That list will be walked at template instantiation
19423 time and access check performed on each typedefs it contains.
19424 Note that this particular code snippet should yield an error because
19425 myint is private to C. */
19428 append_type_to_template_for_access_check (tree templ,
19431 location_t location)
19433 qualified_typedef_usage_t *iter;
19436 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
19438 /* Make sure we don't append the type to the template twice. */
19439 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
19440 get_types_needing_access_check (templ),
19442 if (iter->typedef_decl == type_decl && scope == iter->context)
19445 append_type_to_template_for_access_check_1 (templ, type_decl,
19449 /* Set up the hash tables for template instantiations. */
19452 init_template_processing (void)
19454 decl_specializations = htab_create_ggc (37,
19455 hash_specialization,
19456 eq_specializations,
19458 type_specializations = htab_create_ggc (37,
19459 hash_specialization,
19460 eq_specializations,
19464 /* Print stats about the template hash tables for -fstats. */
19467 print_template_statistics (void)
19469 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
19470 "%f collisions\n", (long) htab_size (decl_specializations),
19471 (long) htab_elements (decl_specializations),
19472 htab_collisions (decl_specializations));
19473 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
19474 "%f collisions\n", (long) htab_size (type_specializations),
19475 (long) htab_elements (type_specializations),
19476 htab_collisions (type_specializations));
19479 #include "gt-cp-pt.h"