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 /* If the instantiation in question still has unbound template parms,
7494 we don't really care if we can't instantiate it, so just return.
7495 This happens with base instantiation for implicit `typename'. */
7496 if (uses_template_parms (d))
7499 last_template_error_tick = tinst_level_tick;
7500 error ("template instantiation depth exceeds maximum of %d (use "
7501 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7502 max_tinst_depth, d);
7504 print_instantiation_context ();
7509 new_level = ggc_alloc_tinst_level ();
7510 new_level->decl = d;
7511 new_level->locus = input_location;
7512 new_level->in_system_header_p = in_system_header;
7513 new_level->next = current_tinst_level;
7514 current_tinst_level = new_level;
7517 #ifdef GATHER_STATISTICS
7518 if (tinst_depth > depth_reached)
7519 depth_reached = tinst_depth;
7526 /* We're done instantiating this template; return to the instantiation
7530 pop_tinst_level (void)
7532 /* Restore the filename and line number stashed away when we started
7533 this instantiation. */
7534 input_location = current_tinst_level->locus;
7535 current_tinst_level = current_tinst_level->next;
7540 /* We're instantiating a deferred template; restore the template
7541 instantiation context in which the instantiation was requested, which
7542 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7545 reopen_tinst_level (struct tinst_level *level)
7547 struct tinst_level *t;
7550 for (t = level; t; t = t->next)
7553 current_tinst_level = level;
7558 /* Returns the TINST_LEVEL which gives the original instantiation
7561 struct tinst_level *
7562 outermost_tinst_level (void)
7564 struct tinst_level *level = current_tinst_level;
7567 level = level->next;
7571 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7574 parameter_of_template_p (tree parm, tree templ)
7579 if (!parm || !templ)
7582 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7583 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7585 parms = DECL_TEMPLATE_PARMS (templ);
7586 parms = INNERMOST_TEMPLATE_PARMS (parms);
7588 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7589 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7595 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7596 vector of template arguments, as for tsubst.
7598 Returns an appropriate tsubst'd friend declaration. */
7601 tsubst_friend_function (tree decl, tree args)
7605 if (TREE_CODE (decl) == FUNCTION_DECL
7606 && DECL_TEMPLATE_INSTANTIATION (decl)
7607 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7608 /* This was a friend declared with an explicit template
7609 argument list, e.g.:
7613 to indicate that f was a template instantiation, not a new
7614 function declaration. Now, we have to figure out what
7615 instantiation of what template. */
7617 tree template_id, arglist, fns;
7620 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7622 /* Friend functions are looked up in the containing namespace scope.
7623 We must enter that scope, to avoid finding member functions of the
7624 current class with same name. */
7625 push_nested_namespace (ns);
7626 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7627 tf_warning_or_error, NULL_TREE,
7628 /*integral_constant_expression_p=*/false);
7629 pop_nested_namespace (ns);
7630 arglist = tsubst (DECL_TI_ARGS (decl), args,
7631 tf_warning_or_error, NULL_TREE);
7632 template_id = lookup_template_function (fns, arglist);
7634 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7635 tmpl = determine_specialization (template_id, new_friend,
7637 /*need_member_template=*/0,
7638 TREE_VEC_LENGTH (args),
7640 return instantiate_template (tmpl, new_args, tf_error);
7643 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7645 /* The NEW_FRIEND will look like an instantiation, to the
7646 compiler, but is not an instantiation from the point of view of
7647 the language. For example, we might have had:
7649 template <class T> struct S {
7650 template <class U> friend void f(T, U);
7653 Then, in S<int>, template <class U> void f(int, U) is not an
7654 instantiation of anything. */
7655 if (new_friend == error_mark_node)
7656 return error_mark_node;
7658 DECL_USE_TEMPLATE (new_friend) = 0;
7659 if (TREE_CODE (decl) == TEMPLATE_DECL)
7661 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7662 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7663 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7666 /* The mangled name for the NEW_FRIEND is incorrect. The function
7667 is not a template instantiation and should not be mangled like
7668 one. Therefore, we forget the mangling here; we'll recompute it
7669 later if we need it. */
7670 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7672 SET_DECL_RTL (new_friend, NULL);
7673 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7676 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7679 tree new_friend_template_info;
7680 tree new_friend_result_template_info;
7682 int new_friend_is_defn;
7684 /* We must save some information from NEW_FRIEND before calling
7685 duplicate decls since that function will free NEW_FRIEND if
7687 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7688 new_friend_is_defn =
7689 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7690 (template_for_substitution (new_friend)))
7692 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7694 /* This declaration is a `primary' template. */
7695 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7697 new_friend_result_template_info
7698 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7701 new_friend_result_template_info = NULL_TREE;
7703 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7704 if (new_friend_is_defn)
7705 DECL_INITIAL (new_friend) = error_mark_node;
7707 /* Inside pushdecl_namespace_level, we will push into the
7708 current namespace. However, the friend function should go
7709 into the namespace of the template. */
7710 ns = decl_namespace_context (new_friend);
7711 push_nested_namespace (ns);
7712 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7713 pop_nested_namespace (ns);
7715 if (old_decl == error_mark_node)
7716 return error_mark_node;
7718 if (old_decl != new_friend)
7720 /* This new friend declaration matched an existing
7721 declaration. For example, given:
7723 template <class T> void f(T);
7724 template <class U> class C {
7725 template <class T> friend void f(T) {}
7728 the friend declaration actually provides the definition
7729 of `f', once C has been instantiated for some type. So,
7730 old_decl will be the out-of-class template declaration,
7731 while new_friend is the in-class definition.
7733 But, if `f' was called before this point, the
7734 instantiation of `f' will have DECL_TI_ARGS corresponding
7735 to `T' but not to `U', references to which might appear
7736 in the definition of `f'. Previously, the most general
7737 template for an instantiation of `f' was the out-of-class
7738 version; now it is the in-class version. Therefore, we
7739 run through all specialization of `f', adding to their
7740 DECL_TI_ARGS appropriately. In particular, they need a
7741 new set of outer arguments, corresponding to the
7742 arguments for this class instantiation.
7744 The same situation can arise with something like this:
7747 template <class T> class C {
7751 when `C<int>' is instantiated. Now, `f(int)' is defined
7754 if (!new_friend_is_defn)
7755 /* On the other hand, if the in-class declaration does
7756 *not* provide a definition, then we don't want to alter
7757 existing definitions. We can just leave everything
7762 tree new_template = TI_TEMPLATE (new_friend_template_info);
7763 tree new_args = TI_ARGS (new_friend_template_info);
7765 /* Overwrite whatever template info was there before, if
7766 any, with the new template information pertaining to
7768 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7770 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7772 /* We should have called reregister_specialization in
7774 gcc_assert (retrieve_specialization (new_template,
7778 /* Instantiate it if the global has already been used. */
7779 if (DECL_ODR_USED (old_decl))
7780 instantiate_decl (old_decl, /*defer_ok=*/true,
7781 /*expl_inst_class_mem_p=*/false);
7787 /* Indicate that the old function template is a partial
7789 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7790 = new_friend_result_template_info;
7792 gcc_assert (new_template
7793 == most_general_template (new_template));
7794 gcc_assert (new_template != old_decl);
7796 /* Reassign any specializations already in the hash table
7797 to the new more general template, and add the
7798 additional template args. */
7799 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7803 tree spec = TREE_VALUE (t);
7806 elt.tmpl = old_decl;
7807 elt.args = DECL_TI_ARGS (spec);
7808 elt.spec = NULL_TREE;
7810 htab_remove_elt (decl_specializations, &elt);
7813 = add_outermost_template_args (new_args,
7814 DECL_TI_ARGS (spec));
7816 register_specialization
7817 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7820 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7824 /* The information from NEW_FRIEND has been merged into OLD_DECL
7825 by duplicate_decls. */
7826 new_friend = old_decl;
7831 tree context = DECL_CONTEXT (new_friend);
7835 template <class T> class C {
7836 template <class U> friend void C1<U>::f (); // case 1
7837 friend void C2<T>::f (); // case 2
7839 we only need to make sure CONTEXT is a complete type for
7840 case 2. To distinguish between the two cases, we note that
7841 CONTEXT of case 1 remains dependent type after tsubst while
7842 this isn't true for case 2. */
7843 ++processing_template_decl;
7844 dependent_p = dependent_type_p (context);
7845 --processing_template_decl;
7848 && !complete_type_or_else (context, NULL_TREE))
7849 return error_mark_node;
7851 if (COMPLETE_TYPE_P (context))
7853 /* Check to see that the declaration is really present, and,
7854 possibly obtain an improved declaration. */
7855 tree fn = check_classfn (context,
7856 new_friend, NULL_TREE);
7866 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7867 template arguments, as for tsubst.
7869 Returns an appropriate tsubst'd friend type or error_mark_node on
7873 tsubst_friend_class (tree friend_tmpl, tree args)
7879 context = CP_DECL_CONTEXT (friend_tmpl);
7881 if (context != global_namespace)
7883 if (TREE_CODE (context) == NAMESPACE_DECL)
7884 push_nested_namespace (context);
7886 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7889 /* Look for a class template declaration. We look for hidden names
7890 because two friend declarations of the same template are the
7891 same. For example, in:
7894 template <typename> friend class F;
7896 template <typename> struct B {
7897 template <typename> friend class F;
7900 both F templates are the same. */
7901 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7902 /*block_p=*/true, 0,
7903 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7905 /* But, if we don't find one, it might be because we're in a
7906 situation like this:
7914 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7915 for `S<int>', not the TEMPLATE_DECL. */
7916 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7918 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7919 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7922 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7924 /* The friend template has already been declared. Just
7925 check to see that the declarations match, and install any new
7926 default parameters. We must tsubst the default parameters,
7927 of course. We only need the innermost template parameters
7928 because that is all that redeclare_class_template will look
7930 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7931 > TMPL_ARGS_DEPTH (args))
7934 location_t saved_input_location;
7935 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7936 args, tf_warning_or_error);
7938 saved_input_location = input_location;
7939 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7940 redeclare_class_template (TREE_TYPE (tmpl), parms);
7941 input_location = saved_input_location;
7945 friend_type = TREE_TYPE (tmpl);
7949 /* The friend template has not already been declared. In this
7950 case, the instantiation of the template class will cause the
7951 injection of this template into the global scope. */
7952 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7953 if (tmpl == error_mark_node)
7954 return error_mark_node;
7956 /* The new TMPL is not an instantiation of anything, so we
7957 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7958 the new type because that is supposed to be the corresponding
7959 template decl, i.e., TMPL. */
7960 DECL_USE_TEMPLATE (tmpl) = 0;
7961 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7962 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7963 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7964 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7966 /* Inject this template into the global scope. */
7967 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7970 if (context != global_namespace)
7972 if (TREE_CODE (context) == NAMESPACE_DECL)
7973 pop_nested_namespace (context);
7975 pop_nested_class ();
7981 /* Returns zero if TYPE cannot be completed later due to circularity.
7982 Otherwise returns one. */
7985 can_complete_type_without_circularity (tree type)
7987 if (type == NULL_TREE || type == error_mark_node)
7989 else if (COMPLETE_TYPE_P (type))
7991 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7992 return can_complete_type_without_circularity (TREE_TYPE (type));
7993 else if (CLASS_TYPE_P (type)
7994 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8000 /* Apply any attributes which had to be deferred until instantiation
8001 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8002 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8005 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8006 tree args, tsubst_flags_t complain, tree in_decl)
8008 tree last_dep = NULL_TREE;
8012 for (t = attributes; t; t = TREE_CHAIN (t))
8013 if (ATTR_IS_DEPENDENT (t))
8016 attributes = copy_list (attributes);
8020 if (DECL_P (*decl_p))
8022 if (TREE_TYPE (*decl_p) == error_mark_node)
8024 p = &DECL_ATTRIBUTES (*decl_p);
8027 p = &TYPE_ATTRIBUTES (*decl_p);
8031 tree late_attrs = NULL_TREE;
8032 tree *q = &late_attrs;
8034 for (*p = attributes; *p; )
8037 if (ATTR_IS_DEPENDENT (t))
8039 *p = TREE_CHAIN (t);
8040 TREE_CHAIN (t) = NULL_TREE;
8041 /* If the first attribute argument is an identifier, don't
8042 pass it through tsubst. Attributes like mode, format,
8043 cleanup and several target specific attributes expect it
8046 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8047 && TREE_VALUE (TREE_VALUE (t))
8048 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8049 == IDENTIFIER_NODE))
8052 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8054 /*integral_constant_expression_p=*/false);
8055 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8057 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8062 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8063 /*integral_constant_expression_p=*/false);
8065 q = &TREE_CHAIN (t);
8068 p = &TREE_CHAIN (t);
8071 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8075 /* Perform (or defer) access check for typedefs that were referenced
8076 from within the template TMPL code.
8077 This is a subroutine of instantiate_template and instantiate_class_template.
8078 TMPL is the template to consider and TARGS is the list of arguments of
8082 perform_typedefs_access_check (tree tmpl, tree targs)
8084 location_t saved_location;
8086 qualified_typedef_usage_t *iter;
8089 || (!CLASS_TYPE_P (tmpl)
8090 && TREE_CODE (tmpl) != FUNCTION_DECL))
8093 saved_location = input_location;
8094 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8095 get_types_needing_access_check (tmpl),
8098 tree type_decl = iter->typedef_decl;
8099 tree type_scope = iter->context;
8101 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8104 if (uses_template_parms (type_decl))
8105 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8106 if (uses_template_parms (type_scope))
8107 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8109 /* Make access check error messages point to the location
8110 of the use of the typedef. */
8111 input_location = iter->locus;
8112 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8113 type_decl, type_decl);
8115 input_location = saved_location;
8119 instantiate_class_template_1 (tree type)
8121 tree templ, args, pattern, t, member;
8125 unsigned int saved_maximum_field_alignment;
8127 if (type == error_mark_node)
8128 return error_mark_node;
8130 if (COMPLETE_OR_OPEN_TYPE_P (type)
8131 || uses_template_parms (type))
8134 /* Figure out which template is being instantiated. */
8135 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8136 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8138 /* Determine what specialization of the original template to
8140 t = most_specialized_class (type, templ, tf_warning_or_error);
8141 if (t == error_mark_node)
8143 TYPE_BEING_DEFINED (type) = 1;
8144 return error_mark_node;
8148 /* This TYPE is actually an instantiation of a partial
8149 specialization. We replace the innermost set of ARGS with
8150 the arguments appropriate for substitution. For example,
8153 template <class T> struct S {};
8154 template <class T> struct S<T*> {};
8156 and supposing that we are instantiating S<int*>, ARGS will
8157 presently be {int*} -- but we need {int}. */
8158 pattern = TREE_TYPE (t);
8159 args = TREE_PURPOSE (t);
8163 pattern = TREE_TYPE (templ);
8164 args = CLASSTYPE_TI_ARGS (type);
8167 /* If the template we're instantiating is incomplete, then clearly
8168 there's nothing we can do. */
8169 if (!COMPLETE_TYPE_P (pattern))
8172 /* If we've recursively instantiated too many templates, stop. */
8173 if (! push_tinst_level (type))
8176 /* Now we're really doing the instantiation. Mark the type as in
8177 the process of being defined. */
8178 TYPE_BEING_DEFINED (type) = 1;
8180 /* We may be in the middle of deferred access check. Disable
8182 push_deferring_access_checks (dk_no_deferred);
8184 push_to_top_level ();
8185 /* Use #pragma pack from the template context. */
8186 saved_maximum_field_alignment = maximum_field_alignment;
8187 maximum_field_alignment = TYPE_PRECISION (pattern);
8189 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8191 /* Set the input location to the most specialized template definition.
8192 This is needed if tsubsting causes an error. */
8193 typedecl = TYPE_MAIN_DECL (pattern);
8194 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8195 DECL_SOURCE_LOCATION (typedecl);
8197 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
8198 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
8199 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
8200 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
8201 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
8202 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
8203 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
8204 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
8205 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
8206 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
8207 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8208 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8209 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8210 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8211 if (ANON_AGGR_TYPE_P (pattern))
8212 SET_ANON_AGGR_TYPE_P (type);
8213 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8215 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8216 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8218 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8220 pbinfo = TYPE_BINFO (pattern);
8222 /* We should never instantiate a nested class before its enclosing
8223 class; we need to look up the nested class by name before we can
8224 instantiate it, and that lookup should instantiate the enclosing
8226 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8227 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8229 base_list = NULL_TREE;
8230 if (BINFO_N_BASE_BINFOS (pbinfo))
8236 /* We must enter the scope containing the type, as that is where
8237 the accessibility of types named in dependent bases are
8239 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8241 /* Substitute into each of the bases to determine the actual
8243 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8246 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8247 tree expanded_bases = NULL_TREE;
8250 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8253 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8254 args, tf_error, NULL_TREE);
8255 if (expanded_bases == error_mark_node)
8258 len = TREE_VEC_LENGTH (expanded_bases);
8261 for (idx = 0; idx < len; idx++)
8264 /* Extract the already-expanded base class. */
8265 base = TREE_VEC_ELT (expanded_bases, idx);
8267 /* Substitute to figure out the base class. */
8268 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8271 if (base == error_mark_node)
8274 base_list = tree_cons (access, base, base_list);
8275 if (BINFO_VIRTUAL_P (pbase_binfo))
8276 TREE_TYPE (base_list) = integer_type_node;
8280 /* The list is now in reverse order; correct that. */
8281 base_list = nreverse (base_list);
8284 pop_scope (pushed_scope);
8286 /* Now call xref_basetypes to set up all the base-class
8288 xref_basetypes (type, base_list);
8290 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8291 (int) ATTR_FLAG_TYPE_IN_PLACE,
8292 args, tf_error, NULL_TREE);
8293 fixup_attribute_variants (type);
8295 /* Now that our base classes are set up, enter the scope of the
8296 class, so that name lookups into base classes, etc. will work
8297 correctly. This is precisely analogous to what we do in
8298 begin_class_definition when defining an ordinary non-template
8299 class, except we also need to push the enclosing classes. */
8300 push_nested_class (type);
8302 /* Now members are processed in the order of declaration. */
8303 for (member = CLASSTYPE_DECL_LIST (pattern);
8304 member; member = TREE_CHAIN (member))
8306 tree t = TREE_VALUE (member);
8308 if (TREE_PURPOSE (member))
8312 /* Build new CLASSTYPE_NESTED_UTDS. */
8315 bool class_template_p;
8317 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8318 && TYPE_LANG_SPECIFIC (t)
8319 && CLASSTYPE_IS_TEMPLATE (t));
8320 /* If the member is a class template, then -- even after
8321 substitution -- there may be dependent types in the
8322 template argument list for the class. We increment
8323 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8324 that function will assume that no types are dependent
8325 when outside of a template. */
8326 if (class_template_p)
8327 ++processing_template_decl;
8328 newtag = tsubst (t, args, tf_error, NULL_TREE);
8329 if (class_template_p)
8330 --processing_template_decl;
8331 if (newtag == error_mark_node)
8334 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8336 tree name = TYPE_IDENTIFIER (t);
8338 if (class_template_p)
8339 /* Unfortunately, lookup_template_class sets
8340 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8341 instantiation (i.e., for the type of a member
8342 template class nested within a template class.)
8343 This behavior is required for
8344 maybe_process_partial_specialization to work
8345 correctly, but is not accurate in this case;
8346 the TAG is not an instantiation of anything.
8347 (The corresponding TEMPLATE_DECL is an
8348 instantiation, but the TYPE is not.) */
8349 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8351 /* Now, we call pushtag to put this NEWTAG into the scope of
8352 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8353 pushtag calling push_template_decl. We don't have to do
8354 this for enums because it will already have been done in
8357 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8358 pushtag (name, newtag, /*tag_scope=*/ts_current);
8361 else if (TREE_CODE (t) == FUNCTION_DECL
8362 || DECL_FUNCTION_TEMPLATE_P (t))
8364 /* Build new TYPE_METHODS. */
8367 if (TREE_CODE (t) == TEMPLATE_DECL)
8368 ++processing_template_decl;
8369 r = tsubst (t, args, tf_error, NULL_TREE);
8370 if (TREE_CODE (t) == TEMPLATE_DECL)
8371 --processing_template_decl;
8372 set_current_access_from_decl (r);
8373 finish_member_declaration (r);
8377 /* Build new TYPE_FIELDS. */
8378 if (TREE_CODE (t) == STATIC_ASSERT)
8381 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8382 tf_warning_or_error, NULL_TREE,
8383 /*integral_constant_expression_p=*/true);
8384 finish_static_assert (condition,
8385 STATIC_ASSERT_MESSAGE (t),
8386 STATIC_ASSERT_SOURCE_LOCATION (t),
8389 else if (TREE_CODE (t) != CONST_DECL)
8393 /* The file and line for this declaration, to
8394 assist in error message reporting. Since we
8395 called push_tinst_level above, we don't need to
8397 input_location = DECL_SOURCE_LOCATION (t);
8399 if (TREE_CODE (t) == TEMPLATE_DECL)
8400 ++processing_template_decl;
8401 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8402 if (TREE_CODE (t) == TEMPLATE_DECL)
8403 --processing_template_decl;
8404 if (TREE_CODE (r) == VAR_DECL)
8408 [t]he initialization (and any associated
8409 side-effects) of a static data member does
8410 not occur unless the static data member is
8411 itself used in a way that requires the
8412 definition of the static data member to
8415 Therefore, we do not substitute into the
8416 initialized for the static data member here. */
8417 finish_static_data_member_decl
8420 /*init_const_expr_p=*/false,
8421 /*asmspec_tree=*/NULL_TREE,
8424 else if (TREE_CODE (r) == FIELD_DECL)
8426 /* Determine whether R has a valid type and can be
8427 completed later. If R is invalid, then it is
8428 replaced by error_mark_node so that it will not be
8429 added to TYPE_FIELDS. */
8430 tree rtype = TREE_TYPE (r);
8431 if (can_complete_type_without_circularity (rtype))
8432 complete_type (rtype);
8434 if (!COMPLETE_TYPE_P (rtype))
8436 cxx_incomplete_type_error (r, rtype);
8437 r = error_mark_node;
8441 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8442 such a thing will already have been added to the field
8443 list by tsubst_enum in finish_member_declaration in the
8444 CLASSTYPE_NESTED_UTDS case above. */
8445 if (!(TREE_CODE (r) == TYPE_DECL
8446 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8447 && DECL_ARTIFICIAL (r)))
8449 set_current_access_from_decl (r);
8450 finish_member_declaration (r);
8457 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8459 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8461 tree friend_type = t;
8462 bool adjust_processing_template_decl = false;
8464 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8466 /* template <class T> friend class C; */
8467 friend_type = tsubst_friend_class (friend_type, args);
8468 adjust_processing_template_decl = true;
8470 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8472 /* template <class T> friend class C::D; */
8473 friend_type = tsubst (friend_type, args,
8474 tf_warning_or_error, NULL_TREE);
8475 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8476 friend_type = TREE_TYPE (friend_type);
8477 adjust_processing_template_decl = true;
8479 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8480 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8482 /* This could be either
8486 when dependent_type_p is false or
8488 template <class U> friend class T::C;
8491 friend_type = tsubst (friend_type, args,
8492 tf_warning_or_error, NULL_TREE);
8493 /* Bump processing_template_decl for correct
8494 dependent_type_p calculation. */
8495 ++processing_template_decl;
8496 if (dependent_type_p (friend_type))
8497 adjust_processing_template_decl = true;
8498 --processing_template_decl;
8500 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8501 && hidden_name_p (TYPE_NAME (friend_type)))
8505 where C hasn't been declared yet. Let's lookup name
8506 from namespace scope directly, bypassing any name that
8507 come from dependent base class. */
8508 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8510 /* The call to xref_tag_from_type does injection for friend
8512 push_nested_namespace (ns);
8514 xref_tag_from_type (friend_type, NULL_TREE,
8515 /*tag_scope=*/ts_current);
8516 pop_nested_namespace (ns);
8518 else if (uses_template_parms (friend_type))
8519 /* friend class C<T>; */
8520 friend_type = tsubst (friend_type, args,
8521 tf_warning_or_error, NULL_TREE);
8526 where C is already declared or
8528 friend class C<int>;
8530 We don't have to do anything in these cases. */
8532 if (adjust_processing_template_decl)
8533 /* Trick make_friend_class into realizing that the friend
8534 we're adding is a template, not an ordinary class. It's
8535 important that we use make_friend_class since it will
8536 perform some error-checking and output cross-reference
8538 ++processing_template_decl;
8540 if (friend_type != error_mark_node)
8541 make_friend_class (type, friend_type, /*complain=*/false);
8543 if (adjust_processing_template_decl)
8544 --processing_template_decl;
8548 /* Build new DECL_FRIENDLIST. */
8551 /* The file and line for this declaration, to
8552 assist in error message reporting. Since we
8553 called push_tinst_level above, we don't need to
8555 input_location = DECL_SOURCE_LOCATION (t);
8557 if (TREE_CODE (t) == TEMPLATE_DECL)
8559 ++processing_template_decl;
8560 push_deferring_access_checks (dk_no_check);
8563 r = tsubst_friend_function (t, args);
8564 add_friend (type, r, /*complain=*/false);
8565 if (TREE_CODE (t) == TEMPLATE_DECL)
8567 pop_deferring_access_checks ();
8568 --processing_template_decl;
8574 if (CLASSTYPE_LAMBDA_EXPR (type))
8575 maybe_add_lambda_conv_op (type);
8577 /* Set the file and line number information to whatever is given for
8578 the class itself. This puts error messages involving generated
8579 implicit functions at a predictable point, and the same point
8580 that would be used for non-template classes. */
8581 input_location = DECL_SOURCE_LOCATION (typedecl);
8583 unreverse_member_declarations (type);
8584 finish_struct_1 (type);
8585 TYPE_BEING_DEFINED (type) = 0;
8587 /* We don't instantiate default arguments for member functions. 14.7.1:
8589 The implicit instantiation of a class template specialization causes
8590 the implicit instantiation of the declarations, but not of the
8591 definitions or default arguments, of the class member functions,
8592 member classes, static data members and member templates.... */
8594 /* Some typedefs referenced from within the template code need to be access
8595 checked at template instantiation time, i.e now. These types were
8596 added to the template at parsing time. Let's get those and perform
8597 the access checks then. */
8598 perform_typedefs_access_check (pattern, args);
8599 perform_deferred_access_checks ();
8600 pop_nested_class ();
8601 maximum_field_alignment = saved_maximum_field_alignment;
8602 pop_from_top_level ();
8603 pop_deferring_access_checks ();
8606 /* The vtable for a template class can be emitted in any translation
8607 unit in which the class is instantiated. When there is no key
8608 method, however, finish_struct_1 will already have added TYPE to
8609 the keyed_classes list. */
8610 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8611 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8616 /* Wrapper for instantiate_class_template_1. */
8619 instantiate_class_template (tree type)
8622 timevar_push (TV_TEMPLATE_INST);
8623 ret = instantiate_class_template_1 (type);
8624 timevar_pop (TV_TEMPLATE_INST);
8629 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8635 else if (TYPE_P (t))
8636 r = tsubst (t, args, complain, in_decl);
8639 if (!(complain & tf_warning))
8640 ++c_inhibit_evaluation_warnings;
8641 r = tsubst_expr (t, args, complain, in_decl,
8642 /*integral_constant_expression_p=*/true);
8643 if (!(complain & tf_warning))
8644 --c_inhibit_evaluation_warnings;
8649 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8650 NONTYPE_ARGUMENT_PACK. */
8653 make_fnparm_pack (tree spec_parm)
8655 /* Collect all of the extra "packed" parameters into an
8659 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8660 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8661 int i, len = list_length (spec_parm);
8663 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8664 parmvec = make_tree_vec (len);
8665 parmtypevec = make_tree_vec (len);
8666 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8668 TREE_VEC_ELT (parmvec, i) = spec_parm;
8669 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8672 /* Build the argument packs. */
8673 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8674 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8675 TREE_TYPE (argpack) = argtypepack;
8680 /* Substitute ARGS into T, which is an pack expansion
8681 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8682 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8683 (if only a partial substitution could be performed) or
8684 ERROR_MARK_NODE if there was an error. */
8686 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8690 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8694 htab_t saved_local_specializations = NULL;
8696 gcc_assert (PACK_EXPANSION_P (t));
8697 pattern = PACK_EXPANSION_PATTERN (t);
8699 /* Determine the argument packs that will instantiate the parameter
8700 packs used in the expansion expression. While we're at it,
8701 compute the number of arguments to be expanded and make sure it
8703 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8704 pack = TREE_CHAIN (pack))
8706 tree parm_pack = TREE_VALUE (pack);
8707 tree arg_pack = NULL_TREE;
8708 tree orig_arg = NULL_TREE;
8710 if (TREE_CODE (parm_pack) == PARM_DECL)
8712 if (!cp_unevaluated_operand)
8713 arg_pack = retrieve_local_specialization (parm_pack);
8716 /* We can't rely on local_specializations for a parameter
8717 name used later in a function declaration (such as in a
8718 late-specified return type). Even if it exists, it might
8719 have the wrong value for a recursive call. Just make a
8720 dummy decl, since it's only used for its type. */
8721 arg_pack = tsubst_decl (parm_pack, args, complain);
8722 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
8723 /* Partial instantiation of the parm_pack, we can't build
8724 up an argument pack yet. */
8725 arg_pack = NULL_TREE;
8727 arg_pack = make_fnparm_pack (arg_pack);
8732 int level, idx, levels;
8733 template_parm_level_and_index (parm_pack, &level, &idx);
8735 levels = TMPL_ARGS_DEPTH (args);
8736 if (level <= levels)
8737 arg_pack = TMPL_ARG (args, level, idx);
8740 orig_arg = arg_pack;
8741 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8742 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8744 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8745 /* This can only happen if we forget to expand an argument
8746 pack somewhere else. Just return an error, silently. */
8748 result = make_tree_vec (1);
8749 TREE_VEC_ELT (result, 0) = error_mark_node;
8753 /* For clarity in the comments below let's use the
8754 representation 'argument_pack<elements>' to denote an
8755 argument pack and its elements.
8757 In the 'if' block below, we want to detect cases where
8758 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
8759 check if ARG_PACK is an argument pack which sole element is
8760 the expansion of PARM_PACK. That argument pack is typically
8761 created by template_parm_to_arg when passed a parameter
8764 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8765 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8767 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8768 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8769 /* So we have an argument_pack<P...>. We want to test if P
8770 is actually PARM_PACK. We will not use cp_tree_equal to
8771 test P and PARM_PACK because during type fixup (by
8772 fixup_template_parm) P can be a pre-fixup version of a
8773 type and PARM_PACK be its post-fixup version.
8774 cp_tree_equal would consider them as different even
8775 though we would want to consider them compatible for our
8776 precise purpose here.
8778 Thus we are going to consider that P and PARM_PACK are
8779 compatible if they have the same DECL. */
8780 if ((/* If ARG_PACK is a type parameter pack named by the
8781 same DECL as parm_pack ... */
8783 && TYPE_P (parm_pack)
8784 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
8785 /* ... or if ARG_PACK is a non-type parameter
8786 named by the same DECL as parm_pack ... */
8787 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
8788 && TREE_CODE (parm_pack) == PARM_DECL
8789 && TEMPLATE_PARM_DECL (pattern)
8790 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
8791 && template_parameter_pack_p (pattern))
8792 /* ... then the argument pack that the parameter maps to
8793 is just an expansion of the parameter itself, such as
8794 one would find in the implicit typedef of a class
8795 inside the class itself. Consider this parameter
8796 "unsubstituted", so that we will maintain the outer
8798 arg_pack = NULL_TREE;
8804 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8806 /* It's all-or-nothing with incomplete argument packs. */
8807 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8808 return error_mark_node;
8810 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8815 else if (len != my_len)
8818 /* We got explicit args for some packs but not others;
8819 do nothing now and try again after deduction. */
8821 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8822 error ("mismatched argument pack lengths while expanding "
8826 error ("mismatched argument pack lengths while expanding "
8829 return error_mark_node;
8832 /* Keep track of the parameter packs and their corresponding
8834 packs = tree_cons (parm_pack, arg_pack, packs);
8835 TREE_TYPE (packs) = orig_arg;
8838 /* We can't substitute for this parameter pack. */
8839 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8841 unsubstituted_packs);
8844 /* We cannot expand this expansion expression, because we don't have
8845 all of the argument packs we need. Substitute into the pattern
8846 and return a PACK_EXPANSION_*. The caller will need to deal with
8848 if (unsubstituted_packs)
8851 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8852 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8853 /*integral_constant_expression_p=*/false);
8855 new_pat = tsubst (pattern, args, complain, in_decl);
8856 return make_pack_expansion (new_pat);
8859 /* We could not find any argument packs that work. */
8861 return error_mark_node;
8863 if (cp_unevaluated_operand)
8865 /* We're in a late-specified return type, so create our own local
8866 specializations table; the current table is either NULL or (in the
8867 case of recursive unification) might have bindings that we don't
8868 want to use or alter. */
8869 saved_local_specializations = local_specializations;
8870 local_specializations = htab_create (37,
8871 hash_local_specialization,
8872 eq_local_specializations,
8876 /* For each argument in each argument pack, substitute into the
8878 result = make_tree_vec (len + incomplete);
8879 for (i = 0; i < len + incomplete; ++i)
8881 /* For parameter pack, change the substitution of the parameter
8882 pack to the ith argument in its argument pack, then expand
8884 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8886 tree parm = TREE_PURPOSE (pack);
8888 if (TREE_CODE (parm) == PARM_DECL)
8890 /* Select the Ith argument from the pack. */
8891 tree arg = make_node (ARGUMENT_PACK_SELECT);
8892 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8893 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8895 register_local_specialization (arg, parm);
8901 template_parm_level_and_index (parm, &level, &idx);
8905 /* Select the Ith argument from the pack. */
8906 value = make_node (ARGUMENT_PACK_SELECT);
8907 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8908 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8911 /* Update the corresponding argument. */
8912 TMPL_ARG (args, level, idx) = value;
8916 /* Substitute into the PATTERN with the altered arguments. */
8917 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8918 TREE_VEC_ELT (result, i) =
8919 tsubst_expr (pattern, args, complain, in_decl,
8920 /*integral_constant_expression_p=*/false);
8922 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8925 /* When we have incomplete argument packs, the last "expanded"
8926 result is itself a pack expansion, which allows us
8927 to deduce more arguments. */
8928 TREE_VEC_ELT (result, i) =
8929 make_pack_expansion (TREE_VEC_ELT (result, i));
8931 if (TREE_VEC_ELT (result, i) == error_mark_node)
8933 result = error_mark_node;
8938 /* Update ARGS to restore the substitution from parameter packs to
8939 their argument packs. */
8940 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8942 tree parm = TREE_PURPOSE (pack);
8944 if (TREE_CODE (parm) == PARM_DECL)
8945 register_local_specialization (TREE_TYPE (pack), parm);
8949 template_parm_level_and_index (parm, &level, &idx);
8951 /* Update the corresponding argument. */
8952 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8953 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8956 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8960 if (saved_local_specializations)
8962 htab_delete (local_specializations);
8963 local_specializations = saved_local_specializations;
8969 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8970 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8971 parameter packs; all parms generated from a function parameter pack will
8972 have the same DECL_PARM_INDEX. */
8975 get_pattern_parm (tree parm, tree tmpl)
8977 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8980 if (DECL_ARTIFICIAL (parm))
8982 for (patparm = DECL_ARGUMENTS (pattern);
8983 patparm; patparm = DECL_CHAIN (patparm))
8984 if (DECL_ARTIFICIAL (patparm)
8985 && DECL_NAME (parm) == DECL_NAME (patparm))
8990 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8991 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8992 gcc_assert (DECL_PARM_INDEX (patparm)
8993 == DECL_PARM_INDEX (parm));
8999 /* Substitute ARGS into the vector or list of template arguments T. */
9002 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9005 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9008 if (t == error_mark_node)
9009 return error_mark_node;
9011 len = TREE_VEC_LENGTH (t);
9012 elts = XALLOCAVEC (tree, len);
9014 for (i = 0; i < len; i++)
9016 tree orig_arg = TREE_VEC_ELT (t, i);
9019 if (TREE_CODE (orig_arg) == TREE_VEC)
9020 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9021 else if (PACK_EXPANSION_P (orig_arg))
9023 /* Substitute into an expansion expression. */
9024 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9026 if (TREE_CODE (new_arg) == TREE_VEC)
9027 /* Add to the expanded length adjustment the number of
9028 expanded arguments. We subtract one from this
9029 measurement, because the argument pack expression
9030 itself is already counted as 1 in
9031 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9032 the argument pack is empty. */
9033 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9035 else if (ARGUMENT_PACK_P (orig_arg))
9037 /* Substitute into each of the arguments. */
9038 new_arg = TYPE_P (orig_arg)
9039 ? cxx_make_type (TREE_CODE (orig_arg))
9040 : make_node (TREE_CODE (orig_arg));
9042 SET_ARGUMENT_PACK_ARGS (
9044 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9045 args, complain, in_decl));
9047 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9048 new_arg = error_mark_node;
9050 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9051 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9053 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9055 if (TREE_TYPE (new_arg) == error_mark_node)
9056 new_arg = error_mark_node;
9060 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9062 if (new_arg == error_mark_node)
9063 return error_mark_node;
9066 if (new_arg != orig_arg)
9073 /* Make space for the expanded arguments coming from template
9075 t = make_tree_vec (len + expanded_len_adjust);
9076 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9077 arguments for a member template.
9078 In that case each TREE_VEC in ORIG_T represents a level of template
9079 arguments, and ORIG_T won't carry any non defaulted argument count.
9080 It will rather be the nested TREE_VECs that will carry one.
9081 In other words, ORIG_T carries a non defaulted argument count only
9082 if it doesn't contain any nested TREE_VEC. */
9083 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9085 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9086 count += expanded_len_adjust;
9087 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9089 for (i = 0, out = 0; i < len; i++)
9091 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9092 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9093 && TREE_CODE (elts[i]) == TREE_VEC)
9097 /* Now expand the template argument pack "in place". */
9098 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9099 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9103 TREE_VEC_ELT (t, out) = elts[i];
9111 /* Return the result of substituting ARGS into the template parameters
9112 given by PARMS. If there are m levels of ARGS and m + n levels of
9113 PARMS, then the result will contain n levels of PARMS. For
9114 example, if PARMS is `template <class T> template <class U>
9115 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9116 result will be `template <int*, double, class V>'. */
9119 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9124 /* When substituting into a template, we must set
9125 PROCESSING_TEMPLATE_DECL as the template parameters may be
9126 dependent if they are based on one-another, and the dependency
9127 predicates are short-circuit outside of templates. */
9128 ++processing_template_decl;
9130 for (new_parms = &r;
9131 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9132 new_parms = &(TREE_CHAIN (*new_parms)),
9133 parms = TREE_CHAIN (parms))
9136 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9139 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9143 if (parms == error_mark_node)
9146 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9148 if (tuple == error_mark_node)
9151 TREE_VEC_ELT (new_vec, i) =
9152 tsubst_template_parm (tuple, args, complain);
9156 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9157 - TMPL_ARGS_DEPTH (args)),
9158 new_vec, NULL_TREE);
9161 --processing_template_decl;
9166 /* Return the result of substituting ARGS into one template parameter
9167 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9168 parameter and which TREE_PURPOSE is the default argument of the
9169 template parameter. */
9172 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9174 tree default_value, parm_decl;
9176 if (args == NULL_TREE
9178 || t == error_mark_node)
9181 gcc_assert (TREE_CODE (t) == TREE_LIST);
9183 default_value = TREE_PURPOSE (t);
9184 parm_decl = TREE_VALUE (t);
9186 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9187 if (TREE_CODE (parm_decl) == PARM_DECL
9188 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9189 parm_decl = error_mark_node;
9190 default_value = tsubst_template_arg (default_value, args,
9191 complain, NULL_TREE);
9193 return build_tree_list (default_value, parm_decl);
9196 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9197 type T. If T is not an aggregate or enumeration type, it is
9198 handled as if by tsubst. IN_DECL is as for tsubst. If
9199 ENTERING_SCOPE is nonzero, T is the context for a template which
9200 we are presently tsubst'ing. Return the substituted value. */
9203 tsubst_aggr_type (tree t,
9205 tsubst_flags_t complain,
9212 switch (TREE_CODE (t))
9215 if (TYPE_PTRMEMFUNC_P (t))
9216 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9218 /* Else fall through. */
9221 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9226 int saved_unevaluated_operand;
9227 int saved_inhibit_evaluation_warnings;
9229 /* In "sizeof(X<I>)" we need to evaluate "I". */
9230 saved_unevaluated_operand = cp_unevaluated_operand;
9231 cp_unevaluated_operand = 0;
9232 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9233 c_inhibit_evaluation_warnings = 0;
9235 /* First, determine the context for the type we are looking
9237 context = TYPE_CONTEXT (t);
9240 context = tsubst_aggr_type (context, args, complain,
9241 in_decl, /*entering_scope=*/1);
9242 /* If context is a nested class inside a class template,
9243 it may still need to be instantiated (c++/33959). */
9244 if (TYPE_P (context))
9245 context = complete_type (context);
9248 /* Then, figure out what arguments are appropriate for the
9249 type we are trying to find. For example, given:
9251 template <class T> struct S;
9252 template <class T, class U> void f(T, U) { S<U> su; }
9254 and supposing that we are instantiating f<int, double>,
9255 then our ARGS will be {int, double}, but, when looking up
9256 S we only want {double}. */
9257 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9259 if (argvec == error_mark_node)
9260 r = error_mark_node;
9263 r = lookup_template_class (t, argvec, in_decl, context,
9264 entering_scope, complain);
9265 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9268 cp_unevaluated_operand = saved_unevaluated_operand;
9269 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9274 /* This is not a template type, so there's nothing to do. */
9278 return tsubst (t, args, complain, in_decl);
9282 /* Substitute into the default argument ARG (a default argument for
9283 FN), which has the indicated TYPE. */
9286 tsubst_default_argument (tree fn, tree type, tree arg)
9288 tree saved_class_ptr = NULL_TREE;
9289 tree saved_class_ref = NULL_TREE;
9291 /* This can happen in invalid code. */
9292 if (TREE_CODE (arg) == DEFAULT_ARG)
9295 /* This default argument came from a template. Instantiate the
9296 default argument here, not in tsubst. In the case of
9305 we must be careful to do name lookup in the scope of S<T>,
9306 rather than in the current class. */
9307 push_access_scope (fn);
9308 /* The "this" pointer is not valid in a default argument. */
9311 saved_class_ptr = current_class_ptr;
9312 cp_function_chain->x_current_class_ptr = NULL_TREE;
9313 saved_class_ref = current_class_ref;
9314 cp_function_chain->x_current_class_ref = NULL_TREE;
9317 push_deferring_access_checks(dk_no_deferred);
9318 /* The default argument expression may cause implicitly defined
9319 member functions to be synthesized, which will result in garbage
9320 collection. We must treat this situation as if we were within
9321 the body of function so as to avoid collecting live data on the
9324 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9325 tf_warning_or_error, NULL_TREE,
9326 /*integral_constant_expression_p=*/false);
9328 pop_deferring_access_checks();
9330 /* Restore the "this" pointer. */
9333 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9334 cp_function_chain->x_current_class_ref = saved_class_ref;
9337 /* Make sure the default argument is reasonable. */
9338 arg = check_default_argument (type, arg);
9340 pop_access_scope (fn);
9345 /* Substitute into all the default arguments for FN. */
9348 tsubst_default_arguments (tree fn)
9353 tmpl_args = DECL_TI_ARGS (fn);
9355 /* If this function is not yet instantiated, we certainly don't need
9356 its default arguments. */
9357 if (uses_template_parms (tmpl_args))
9359 /* Don't do this again for clones. */
9360 if (DECL_CLONED_FUNCTION_P (fn))
9363 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9365 arg = TREE_CHAIN (arg))
9366 if (TREE_PURPOSE (arg))
9367 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9369 TREE_PURPOSE (arg));
9372 /* Substitute the ARGS into the T, which is a _DECL. Return the
9373 result of the substitution. Issue error and warning messages under
9374 control of COMPLAIN. */
9377 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9379 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9380 location_t saved_loc;
9385 /* Set the filename and linenumber to improve error-reporting. */
9386 saved_loc = input_location;
9387 input_location = DECL_SOURCE_LOCATION (t);
9389 switch (TREE_CODE (t))
9393 /* We can get here when processing a member function template,
9394 member class template, or template template parameter. */
9395 tree decl = DECL_TEMPLATE_RESULT (t);
9400 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9402 /* Template template parameter is treated here. */
9403 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9404 if (new_type == error_mark_node)
9405 RETURN (error_mark_node);
9408 DECL_CHAIN (r) = NULL_TREE;
9409 TREE_TYPE (r) = new_type;
9410 DECL_TEMPLATE_RESULT (r)
9411 = build_decl (DECL_SOURCE_LOCATION (decl),
9412 TYPE_DECL, DECL_NAME (decl), new_type);
9413 DECL_TEMPLATE_PARMS (r)
9414 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9416 TYPE_NAME (new_type) = r;
9420 /* We might already have an instance of this template.
9421 The ARGS are for the surrounding class type, so the
9422 full args contain the tsubst'd args for the context,
9423 plus the innermost args from the template decl. */
9424 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9425 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9426 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9427 /* Because this is a template, the arguments will still be
9428 dependent, even after substitution. If
9429 PROCESSING_TEMPLATE_DECL is not set, the dependency
9430 predicates will short-circuit. */
9431 ++processing_template_decl;
9432 full_args = tsubst_template_args (tmpl_args, args,
9434 --processing_template_decl;
9435 if (full_args == error_mark_node)
9436 RETURN (error_mark_node);
9438 /* If this is a default template template argument,
9439 tsubst might not have changed anything. */
9440 if (full_args == tmpl_args)
9443 hash = hash_tmpl_and_args (t, full_args);
9444 spec = retrieve_specialization (t, full_args, hash);
9445 if (spec != NULL_TREE)
9451 /* Make a new template decl. It will be similar to the
9452 original, but will record the current template arguments.
9453 We also create a new function declaration, which is just
9454 like the old one, but points to this new template, rather
9455 than the old one. */
9457 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9458 DECL_CHAIN (r) = NULL_TREE;
9460 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9462 if (TREE_CODE (decl) == TYPE_DECL)
9465 ++processing_template_decl;
9466 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9467 --processing_template_decl;
9468 if (new_type == error_mark_node)
9469 RETURN (error_mark_node);
9471 TREE_TYPE (r) = new_type;
9472 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9473 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9474 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9475 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9480 ++processing_template_decl;
9481 new_decl = tsubst (decl, args, complain, in_decl);
9482 --processing_template_decl;
9483 if (new_decl == error_mark_node)
9484 RETURN (error_mark_node);
9486 DECL_TEMPLATE_RESULT (r) = new_decl;
9487 DECL_TI_TEMPLATE (new_decl) = r;
9488 TREE_TYPE (r) = TREE_TYPE (new_decl);
9489 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9490 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9493 SET_DECL_IMPLICIT_INSTANTIATION (r);
9494 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9495 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9497 /* The template parameters for this new template are all the
9498 template parameters for the old template, except the
9499 outermost level of parameters. */
9500 DECL_TEMPLATE_PARMS (r)
9501 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9504 if (PRIMARY_TEMPLATE_P (t))
9505 DECL_PRIMARY_TEMPLATE (r) = r;
9507 if (TREE_CODE (decl) != TYPE_DECL)
9508 /* Record this non-type partial instantiation. */
9509 register_specialization (r, t,
9510 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9518 tree argvec = NULL_TREE;
9526 /* Nobody should be tsubst'ing into non-template functions. */
9527 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9529 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9534 /* If T is not dependent, just return it. We have to
9535 increment PROCESSING_TEMPLATE_DECL because
9536 value_dependent_expression_p assumes that nothing is
9537 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9538 ++processing_template_decl;
9539 dependent_p = value_dependent_expression_p (t);
9540 --processing_template_decl;
9544 /* Calculate the most general template of which R is a
9545 specialization, and the complete set of arguments used to
9547 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9548 argvec = tsubst_template_args (DECL_TI_ARGS
9549 (DECL_TEMPLATE_RESULT
9550 (DECL_TI_TEMPLATE (t))),
9551 args, complain, in_decl);
9553 /* Check to see if we already have this specialization. */
9554 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9555 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9563 /* We can see more levels of arguments than parameters if
9564 there was a specialization of a member template, like
9567 template <class T> struct S { template <class U> void f(); }
9568 template <> template <class U> void S<int>::f(U);
9570 Here, we'll be substituting into the specialization,
9571 because that's where we can find the code we actually
9572 want to generate, but we'll have enough arguments for
9573 the most general template.
9575 We also deal with the peculiar case:
9577 template <class T> struct S {
9578 template <class U> friend void f();
9580 template <class U> void f() {}
9582 template void f<double>();
9584 Here, the ARGS for the instantiation of will be {int,
9585 double}. But, we only need as many ARGS as there are
9586 levels of template parameters in CODE_PATTERN. We are
9587 careful not to get fooled into reducing the ARGS in
9590 template <class T> struct S { template <class U> void f(U); }
9591 template <class T> template <> void S<T>::f(int) {}
9593 which we can spot because the pattern will be a
9594 specialization in this case. */
9595 args_depth = TMPL_ARGS_DEPTH (args);
9597 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9598 if (args_depth > parms_depth
9599 && !DECL_TEMPLATE_SPECIALIZATION (t))
9600 args = get_innermost_template_args (args, parms_depth);
9604 /* This special case arises when we have something like this:
9606 template <class T> struct S {
9607 friend void f<int>(int, double);
9610 Here, the DECL_TI_TEMPLATE for the friend declaration
9611 will be an IDENTIFIER_NODE. We are being called from
9612 tsubst_friend_function, and we want only to create a
9613 new decl (R) with appropriate types so that we can call
9614 determine_specialization. */
9615 gen_tmpl = NULL_TREE;
9618 if (DECL_CLASS_SCOPE_P (t))
9620 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9624 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9625 complain, t, /*entering_scope=*/1);
9630 ctx = DECL_CONTEXT (t);
9632 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9633 if (type == error_mark_node)
9634 RETURN (error_mark_node);
9636 /* We do NOT check for matching decls pushed separately at this
9637 point, as they may not represent instantiations of this
9638 template, and in any case are considered separate under the
9641 DECL_USE_TEMPLATE (r) = 0;
9642 TREE_TYPE (r) = type;
9643 /* Clear out the mangled name and RTL for the instantiation. */
9644 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9645 SET_DECL_RTL (r, NULL);
9646 /* Leave DECL_INITIAL set on deleted instantiations. */
9647 if (!DECL_DELETED_FN (r))
9648 DECL_INITIAL (r) = NULL_TREE;
9649 DECL_CONTEXT (r) = ctx;
9651 if (member && DECL_CONV_FN_P (r))
9652 /* Type-conversion operator. Reconstruct the name, in
9653 case it's the name of one of the template's parameters. */
9654 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9656 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9658 DECL_RESULT (r) = NULL_TREE;
9660 TREE_STATIC (r) = 0;
9661 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9662 DECL_EXTERNAL (r) = 1;
9663 /* If this is an instantiation of a function with internal
9664 linkage, we already know what object file linkage will be
9665 assigned to the instantiation. */
9666 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9667 DECL_DEFER_OUTPUT (r) = 0;
9668 DECL_CHAIN (r) = NULL_TREE;
9669 DECL_PENDING_INLINE_INFO (r) = 0;
9670 DECL_PENDING_INLINE_P (r) = 0;
9671 DECL_SAVED_TREE (r) = NULL_TREE;
9672 DECL_STRUCT_FUNCTION (r) = NULL;
9674 /* We'll re-clone as appropriate in instantiate_template. */
9675 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9677 /* If we aren't complaining now, return on error before we register
9678 the specialization so that we'll complain eventually. */
9679 if ((complain & tf_error) == 0
9680 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9681 && !grok_op_properties (r, /*complain=*/false))
9682 RETURN (error_mark_node);
9684 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9685 this in the special friend case mentioned above where
9686 GEN_TMPL is NULL. */
9689 DECL_TEMPLATE_INFO (r)
9690 = build_template_info (gen_tmpl, argvec);
9691 SET_DECL_IMPLICIT_INSTANTIATION (r);
9692 register_specialization (r, gen_tmpl, argvec, false, hash);
9694 /* We're not supposed to instantiate default arguments
9695 until they are called, for a template. But, for a
9698 template <class T> void f ()
9699 { extern void g(int i = T()); }
9701 we should do the substitution when the template is
9702 instantiated. We handle the member function case in
9703 instantiate_class_template since the default arguments
9704 might refer to other members of the class. */
9706 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9707 && !uses_template_parms (argvec))
9708 tsubst_default_arguments (r);
9711 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9713 /* Copy the list of befriending classes. */
9714 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9716 friends = &TREE_CHAIN (*friends))
9718 *friends = copy_node (*friends);
9719 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9724 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9726 maybe_retrofit_in_chrg (r);
9727 if (DECL_CONSTRUCTOR_P (r))
9728 grok_ctor_properties (ctx, r);
9729 /* If this is an instantiation of a member template, clone it.
9730 If it isn't, that'll be handled by
9731 clone_constructors_and_destructors. */
9732 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9733 clone_function_decl (r, /*update_method_vec_p=*/0);
9735 else if ((complain & tf_error) != 0
9736 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9737 && !grok_op_properties (r, /*complain=*/true))
9738 RETURN (error_mark_node);
9740 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9741 SET_DECL_FRIEND_CONTEXT (r,
9742 tsubst (DECL_FRIEND_CONTEXT (t),
9743 args, complain, in_decl));
9745 /* Possibly limit visibility based on template args. */
9746 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9747 if (DECL_VISIBILITY_SPECIFIED (t))
9749 DECL_VISIBILITY_SPECIFIED (r) = 0;
9751 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9753 determine_visibility (r);
9754 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9755 && !processing_template_decl)
9756 defaulted_late_check (r);
9758 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9759 args, complain, in_decl);
9765 tree type = NULL_TREE;
9767 tree expanded_types = NULL_TREE;
9768 tree prev_r = NULL_TREE;
9769 tree first_r = NULL_TREE;
9771 if (FUNCTION_PARAMETER_PACK_P (t))
9773 /* If there is a local specialization that isn't a
9774 parameter pack, it means that we're doing a "simple"
9775 substitution from inside tsubst_pack_expansion. Just
9776 return the local specialization (which will be a single
9778 tree spec = retrieve_local_specialization (t);
9780 && TREE_CODE (spec) == PARM_DECL
9781 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9784 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9785 the parameters in this function parameter pack. */
9786 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9788 if (TREE_CODE (expanded_types) == TREE_VEC)
9790 len = TREE_VEC_LENGTH (expanded_types);
9792 /* Zero-length parameter packs are boring. Just substitute
9795 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9800 /* All we did was update the type. Make a note of that. */
9801 type = expanded_types;
9802 expanded_types = NULL_TREE;
9806 /* Loop through all of the parameter's we'll build. When T is
9807 a function parameter pack, LEN is the number of expanded
9808 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9810 for (i = 0; i < len; ++i)
9814 if (DECL_TEMPLATE_PARM_P (t))
9815 SET_DECL_TEMPLATE_PARM_P (r);
9818 /* We're on the Ith parameter of the function parameter
9821 /* An argument of a function parameter pack is not a parameter
9823 FUNCTION_PARAMETER_PACK_P (r) = false;
9825 /* Get the Ith type. */
9826 type = TREE_VEC_ELT (expanded_types, i);
9829 /* Rename the parameter to include the index. */
9831 make_ith_pack_parameter_name (DECL_NAME (r), i);
9834 /* We're dealing with a normal parameter. */
9835 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9837 type = type_decays_to (type);
9838 TREE_TYPE (r) = type;
9839 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9841 if (DECL_INITIAL (r))
9843 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9844 DECL_INITIAL (r) = TREE_TYPE (r);
9846 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9850 DECL_CONTEXT (r) = NULL_TREE;
9852 if (!DECL_TEMPLATE_PARM_P (r))
9853 DECL_ARG_TYPE (r) = type_passed_as (type);
9855 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9856 args, complain, in_decl);
9858 /* Keep track of the first new parameter we
9859 generate. That's what will be returned to the
9864 /* Build a proper chain of parameters when substituting
9865 into a function parameter pack. */
9867 DECL_CHAIN (prev_r) = r;
9871 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9872 complain, DECL_CHAIN (t));
9874 /* FIRST_R contains the start of the chain we've built. */
9884 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9885 if (type == error_mark_node)
9886 RETURN (error_mark_node);
9887 TREE_TYPE (r) = type;
9888 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9890 /* DECL_INITIAL gives the number of bits in a bit-field. */
9892 = tsubst_expr (DECL_INITIAL (t), args,
9894 /*integral_constant_expression_p=*/true);
9895 /* We don't have to set DECL_CONTEXT here; it is set by
9896 finish_member_declaration. */
9897 DECL_CHAIN (r) = NULL_TREE;
9898 if (VOID_TYPE_P (type))
9899 error ("instantiation of %q+D as type %qT", r, type);
9901 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9902 args, complain, in_decl);
9907 /* We reach here only for member using decls. */
9908 if (DECL_DEPENDENT_P (t))
9910 r = do_class_using_decl
9911 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9912 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9914 r = error_mark_node;
9917 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9918 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9924 DECL_CHAIN (r) = NULL_TREE;
9931 tree argvec = NULL_TREE;
9932 tree gen_tmpl = NULL_TREE;
9934 tree tmpl = NULL_TREE;
9936 tree type = NULL_TREE;
9939 if (TREE_CODE (t) == TYPE_DECL
9940 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9942 /* If this is the canonical decl, we don't have to
9943 mess with instantiations, and often we can't (for
9944 typename, template type parms and such). Note that
9945 TYPE_NAME is not correct for the above test if
9946 we've copied the type for a typedef. */
9947 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9948 if (type == error_mark_node)
9949 RETURN (error_mark_node);
9950 r = TYPE_NAME (type);
9954 /* Check to see if we already have the specialization we
9957 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9959 /* T is a static data member or namespace-scope entity.
9960 We have to substitute into namespace-scope variables
9961 (even though such entities are never templates) because
9964 template <class T> void f() { extern T t; }
9966 where the entity referenced is not known until
9967 instantiation time. */
9969 ctx = DECL_CONTEXT (t);
9970 if (DECL_CLASS_SCOPE_P (t))
9972 ctx = tsubst_aggr_type (ctx, args,
9974 in_decl, /*entering_scope=*/1);
9975 /* If CTX is unchanged, then T is in fact the
9976 specialization we want. That situation occurs when
9977 referencing a static data member within in its own
9978 class. We can use pointer equality, rather than
9979 same_type_p, because DECL_CONTEXT is always
9981 if (ctx == DECL_CONTEXT (t))
9987 tmpl = DECL_TI_TEMPLATE (t);
9988 gen_tmpl = most_general_template (tmpl);
9989 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9990 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9991 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9996 /* A local variable. */
9998 /* Subsequent calls to pushdecl will fill this in. */
10000 spec = retrieve_local_specialization (t);
10002 /* If we already have the specialization we need, there is
10003 nothing more to do. */
10010 /* Create a new node for the specialization we need. */
10012 if (type == NULL_TREE)
10014 if (is_typedef_decl (t))
10015 type = DECL_ORIGINAL_TYPE (t);
10017 type = TREE_TYPE (t);
10018 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10019 type = strip_array_domain (type);
10020 type = tsubst (type, args, complain, in_decl);
10022 if (TREE_CODE (r) == VAR_DECL)
10024 /* Even if the original location is out of scope, the
10025 newly substituted one is not. */
10026 DECL_DEAD_FOR_LOCAL (r) = 0;
10027 DECL_INITIALIZED_P (r) = 0;
10028 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10029 if (type == error_mark_node)
10030 RETURN (error_mark_node);
10031 if (TREE_CODE (type) == FUNCTION_TYPE)
10033 /* It may seem that this case cannot occur, since:
10038 declares a function, not a variable. However:
10041 template <typename T> void g() { T t; }
10042 template void g<f>();
10044 is an attempt to declare a variable with function
10046 error ("variable %qD has function type",
10047 /* R is not yet sufficiently initialized, so we
10048 just use its name. */
10050 RETURN (error_mark_node);
10052 type = complete_type (type);
10053 /* Wait until cp_finish_decl to set this again, to handle
10054 circular dependency (template/instantiate6.C). */
10055 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10056 type = check_var_type (DECL_NAME (r), type);
10058 if (DECL_HAS_VALUE_EXPR_P (t))
10060 tree ve = DECL_VALUE_EXPR (t);
10061 ve = tsubst_expr (ve, args, complain, in_decl,
10062 /*constant_expression_p=*/false);
10063 SET_DECL_VALUE_EXPR (r, ve);
10066 else if (DECL_SELF_REFERENCE_P (t))
10067 SET_DECL_SELF_REFERENCE_P (r);
10068 TREE_TYPE (r) = type;
10069 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10070 DECL_CONTEXT (r) = ctx;
10071 /* Clear out the mangled name and RTL for the instantiation. */
10072 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10073 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10074 SET_DECL_RTL (r, NULL);
10075 /* The initializer must not be expanded until it is required;
10076 see [temp.inst]. */
10077 DECL_INITIAL (r) = NULL_TREE;
10078 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10079 SET_DECL_RTL (r, NULL);
10080 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10081 if (TREE_CODE (r) == VAR_DECL)
10083 /* Possibly limit visibility based on template args. */
10084 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10085 if (DECL_VISIBILITY_SPECIFIED (t))
10087 DECL_VISIBILITY_SPECIFIED (r) = 0;
10088 DECL_ATTRIBUTES (r)
10089 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10091 determine_visibility (r);
10096 /* A static data member declaration is always marked
10097 external when it is declared in-class, even if an
10098 initializer is present. We mimic the non-template
10099 processing here. */
10100 DECL_EXTERNAL (r) = 1;
10102 register_specialization (r, gen_tmpl, argvec, false, hash);
10103 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10104 SET_DECL_IMPLICIT_INSTANTIATION (r);
10106 else if (cp_unevaluated_operand)
10108 /* We're substituting this var in a decltype outside of its
10109 scope, such as for a lambda return type. Don't add it to
10110 local_specializations, do perform auto deduction. */
10111 tree auto_node = type_uses_auto (type);
10113 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10114 /*constant_expression_p=*/false);
10116 if (auto_node && init)
10118 init = resolve_nondeduced_context (init);
10119 if (describable_type (init))
10121 type = do_auto_deduction (type, init, auto_node);
10122 TREE_TYPE (r) = type;
10127 register_local_specialization (r, t);
10129 DECL_CHAIN (r) = NULL_TREE;
10131 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10133 args, complain, in_decl);
10135 /* Preserve a typedef that names a type. */
10136 if (is_typedef_decl (r))
10138 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10139 set_underlying_type (r);
10142 layout_decl (r, 0);
10147 gcc_unreachable ();
10152 /* Restore the file and line information. */
10153 input_location = saved_loc;
10158 /* Substitute into the ARG_TYPES of a function type. */
10161 tsubst_arg_types (tree arg_types,
10163 tsubst_flags_t complain,
10166 tree remaining_arg_types;
10167 tree type = NULL_TREE;
10169 tree expanded_args = NULL_TREE;
10172 if (!arg_types || arg_types == void_list_node)
10175 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10176 args, complain, in_decl);
10177 if (remaining_arg_types == error_mark_node)
10178 return error_mark_node;
10180 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10182 /* For a pack expansion, perform substitution on the
10183 entire expression. Later on, we'll handle the arguments
10185 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10186 args, complain, in_decl);
10188 if (TREE_CODE (expanded_args) == TREE_VEC)
10189 /* So that we'll spin through the parameters, one by one. */
10190 i = TREE_VEC_LENGTH (expanded_args);
10193 /* We only partially substituted into the parameter
10194 pack. Our type is TYPE_PACK_EXPANSION. */
10195 type = expanded_args;
10196 expanded_args = NULL_TREE;
10204 type = TREE_VEC_ELT (expanded_args, i);
10206 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10208 if (type == error_mark_node)
10209 return error_mark_node;
10210 if (VOID_TYPE_P (type))
10212 if (complain & tf_error)
10214 error ("invalid parameter type %qT", type);
10216 error ("in declaration %q+D", in_decl);
10218 return error_mark_node;
10221 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10222 top-level qualifiers as required. */
10223 type = TYPE_MAIN_VARIANT (type_decays_to (type));
10225 /* We do not substitute into default arguments here. The standard
10226 mandates that they be instantiated only when needed, which is
10227 done in build_over_call. */
10228 default_arg = TREE_PURPOSE (arg_types);
10230 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10232 /* We've instantiated a template before its default arguments
10233 have been parsed. This can happen for a nested template
10234 class, and is not an error unless we require the default
10235 argument in a call of this function. */
10236 remaining_arg_types =
10237 tree_cons (default_arg, type, remaining_arg_types);
10238 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10239 remaining_arg_types);
10242 remaining_arg_types =
10243 hash_tree_cons (default_arg, type, remaining_arg_types);
10246 return remaining_arg_types;
10249 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10250 *not* handle the exception-specification for FNTYPE, because the
10251 initial substitution of explicitly provided template parameters
10252 during argument deduction forbids substitution into the
10253 exception-specification:
10257 All references in the function type of the function template to the
10258 corresponding template parameters are replaced by the specified tem-
10259 plate argument values. If a substitution in a template parameter or
10260 in the function type of the function template results in an invalid
10261 type, type deduction fails. [Note: The equivalent substitution in
10262 exception specifications is done only when the function is instanti-
10263 ated, at which point a program is ill-formed if the substitution
10264 results in an invalid type.] */
10267 tsubst_function_type (tree t,
10269 tsubst_flags_t complain,
10276 /* The TYPE_CONTEXT is not used for function/method types. */
10277 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10279 /* Substitute the return type. */
10280 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10281 if (return_type == error_mark_node)
10282 return error_mark_node;
10283 /* The standard does not presently indicate that creation of a
10284 function type with an invalid return type is a deduction failure.
10285 However, that is clearly analogous to creating an array of "void"
10286 or a reference to a reference. This is core issue #486. */
10287 if (TREE_CODE (return_type) == ARRAY_TYPE
10288 || TREE_CODE (return_type) == FUNCTION_TYPE)
10290 if (complain & tf_error)
10292 if (TREE_CODE (return_type) == ARRAY_TYPE)
10293 error ("function returning an array");
10295 error ("function returning a function");
10297 return error_mark_node;
10300 /* Substitute the argument types. */
10301 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10302 complain, in_decl);
10303 if (arg_types == error_mark_node)
10304 return error_mark_node;
10306 /* Construct a new type node and return it. */
10307 if (TREE_CODE (t) == FUNCTION_TYPE)
10309 fntype = build_function_type (return_type, arg_types);
10310 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10314 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10315 if (! MAYBE_CLASS_TYPE_P (r))
10319 Type deduction may fail for any of the following
10322 -- Attempting to create "pointer to member of T" when T
10323 is not a class type. */
10324 if (complain & tf_error)
10325 error ("creating pointer to member function of non-class type %qT",
10327 return error_mark_node;
10330 fntype = build_method_type_directly (r, return_type,
10331 TREE_CHAIN (arg_types));
10333 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10338 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10339 ARGS into that specification, and return the substituted
10340 specification. If there is no specification, return NULL_TREE. */
10343 tsubst_exception_specification (tree fntype,
10345 tsubst_flags_t complain,
10351 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10352 new_specs = NULL_TREE;
10353 if (specs && TREE_PURPOSE (specs))
10355 /* A noexcept-specifier. */
10356 new_specs = tsubst_copy_and_build
10357 (TREE_PURPOSE (specs), args, complain, in_decl, /*function_p=*/false,
10358 /*integral_constant_expression_p=*/true);
10359 new_specs = build_noexcept_spec (new_specs, complain);
10363 if (! TREE_VALUE (specs))
10370 tree expanded_specs = NULL_TREE;
10372 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10374 /* Expand the pack expansion type. */
10375 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10379 if (expanded_specs == error_mark_node)
10380 return error_mark_node;
10381 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10382 len = TREE_VEC_LENGTH (expanded_specs);
10385 /* We're substituting into a member template, so
10386 we got a TYPE_PACK_EXPANSION back. Add that
10387 expansion and move on. */
10388 gcc_assert (TREE_CODE (expanded_specs)
10389 == TYPE_PACK_EXPANSION);
10390 new_specs = add_exception_specifier (new_specs,
10393 specs = TREE_CHAIN (specs);
10398 for (i = 0; i < len; ++i)
10400 if (expanded_specs)
10401 spec = TREE_VEC_ELT (expanded_specs, i);
10403 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10404 if (spec == error_mark_node)
10406 new_specs = add_exception_specifier (new_specs, spec,
10410 specs = TREE_CHAIN (specs);
10416 /* Take the tree structure T and replace template parameters used
10417 therein with the argument vector ARGS. IN_DECL is an associated
10418 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10419 Issue error and warning messages under control of COMPLAIN. Note
10420 that we must be relatively non-tolerant of extensions here, in
10421 order to preserve conformance; if we allow substitutions that
10422 should not be allowed, we may allow argument deductions that should
10423 not succeed, and therefore report ambiguous overload situations
10424 where there are none. In theory, we could allow the substitution,
10425 but indicate that it should have failed, and allow our caller to
10426 make sure that the right thing happens, but we don't try to do this
10429 This function is used for dealing with types, decls and the like;
10430 for expressions, use tsubst_expr or tsubst_copy. */
10433 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10435 enum tree_code code;
10438 if (t == NULL_TREE || t == error_mark_node
10439 || t == integer_type_node
10440 || t == void_type_node
10441 || t == char_type_node
10442 || t == unknown_type_node
10443 || TREE_CODE (t) == NAMESPACE_DECL
10444 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10448 return tsubst_decl (t, args, complain);
10450 if (args == NULL_TREE)
10453 code = TREE_CODE (t);
10455 if (code == IDENTIFIER_NODE)
10456 type = IDENTIFIER_TYPE_VALUE (t);
10458 type = TREE_TYPE (t);
10460 gcc_assert (type != unknown_type_node);
10462 /* Reuse typedefs. We need to do this to handle dependent attributes,
10463 such as attribute aligned. */
10465 && typedef_variant_p (t))
10467 tree decl = TYPE_NAME (t);
10469 if (DECL_CLASS_SCOPE_P (decl)
10470 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10471 && uses_template_parms (DECL_CONTEXT (decl)))
10473 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10474 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10475 r = retrieve_specialization (tmpl, gen_args, 0);
10477 else if (DECL_FUNCTION_SCOPE_P (decl)
10478 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10479 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10480 r = retrieve_local_specialization (decl);
10482 /* The typedef is from a non-template context. */
10488 r = cp_build_qualified_type_real
10489 (r, cp_type_quals (t) | cp_type_quals (r),
10490 complain | tf_ignore_bad_quals);
10493 /* Else we must be instantiating the typedef, so fall through. */
10497 && code != TYPENAME_TYPE
10498 && code != TEMPLATE_TYPE_PARM
10499 && code != IDENTIFIER_NODE
10500 && code != FUNCTION_TYPE
10501 && code != METHOD_TYPE)
10502 type = tsubst (type, args, complain, in_decl);
10503 if (type == error_mark_node)
10504 return error_mark_node;
10510 case ENUMERAL_TYPE:
10511 return tsubst_aggr_type (t, args, complain, in_decl,
10512 /*entering_scope=*/0);
10515 case IDENTIFIER_NODE:
10526 if (t == integer_type_node)
10529 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10530 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10534 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10536 max = tsubst_expr (omax, args, complain, in_decl,
10537 /*integral_constant_expression_p=*/false);
10539 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10541 if (TREE_CODE (max) == NOP_EXPR
10542 && TREE_SIDE_EFFECTS (omax)
10543 && !TREE_TYPE (max))
10544 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10546 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10547 with TREE_SIDE_EFFECTS that indicates this is not an integral
10548 constant expression. */
10549 if (processing_template_decl
10550 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10552 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10553 TREE_SIDE_EFFECTS (max) = 1;
10556 return compute_array_index_type (NULL_TREE, max, complain);
10559 case TEMPLATE_TYPE_PARM:
10560 case TEMPLATE_TEMPLATE_PARM:
10561 case BOUND_TEMPLATE_TEMPLATE_PARM:
10562 case TEMPLATE_PARM_INDEX:
10567 tree arg = NULL_TREE;
10571 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10572 template_parm_level_and_index (t, &level, &idx);
10574 levels = TMPL_ARGS_DEPTH (args);
10575 if (level <= levels)
10577 arg = TMPL_ARG (args, level, idx);
10579 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10580 /* See through ARGUMENT_PACK_SELECT arguments. */
10581 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10584 if (arg == error_mark_node)
10585 return error_mark_node;
10586 else if (arg != NULL_TREE)
10588 if (ARGUMENT_PACK_P (arg))
10589 /* If ARG is an argument pack, we don't actually want to
10590 perform a substitution here, because substitutions
10591 for argument packs are only done
10592 element-by-element. We can get to this point when
10593 substituting the type of a non-type template
10594 parameter pack, when that type actually contains
10595 template parameter packs from an outer template, e.g.,
10597 template<typename... Types> struct A {
10598 template<Types... Values> struct B { };
10602 if (code == TEMPLATE_TYPE_PARM)
10605 gcc_assert (TYPE_P (arg));
10607 quals = cp_type_quals (arg) | cp_type_quals (t);
10609 return cp_build_qualified_type_real
10610 (arg, quals, complain | tf_ignore_bad_quals);
10612 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10614 /* We are processing a type constructed from a
10615 template template parameter. */
10616 tree argvec = tsubst (TYPE_TI_ARGS (t),
10617 args, complain, in_decl);
10618 if (argvec == error_mark_node)
10619 return error_mark_node;
10621 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10622 are resolving nested-types in the signature of a
10623 member function templates. Otherwise ARG is a
10624 TEMPLATE_DECL and is the real template to be
10626 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10627 arg = TYPE_NAME (arg);
10629 r = lookup_template_class (arg,
10631 DECL_CONTEXT (arg),
10632 /*entering_scope=*/0,
10634 return cp_build_qualified_type_real
10635 (r, cp_type_quals (t), complain);
10638 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10639 return unshare_expr (arg);
10643 /* This can happen during the attempted tsubst'ing in
10644 unify. This means that we don't yet have any information
10645 about the template parameter in question. */
10648 /* If we get here, we must have been looking at a parm for a
10649 more deeply nested template. Make a new version of this
10650 template parameter, but with a lower level. */
10653 case TEMPLATE_TYPE_PARM:
10654 case TEMPLATE_TEMPLATE_PARM:
10655 case BOUND_TEMPLATE_TEMPLATE_PARM:
10656 if (cp_type_quals (t))
10658 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10659 r = cp_build_qualified_type_real
10660 (r, cp_type_quals (t),
10661 complain | (code == TEMPLATE_TYPE_PARM
10662 ? tf_ignore_bad_quals : 0));
10667 TEMPLATE_TYPE_PARM_INDEX (r)
10668 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10669 r, levels, args, complain);
10670 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10671 TYPE_MAIN_VARIANT (r) = r;
10672 TYPE_POINTER_TO (r) = NULL_TREE;
10673 TYPE_REFERENCE_TO (r) = NULL_TREE;
10675 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10676 /* We have reduced the level of the template
10677 template parameter, but not the levels of its
10678 template parameters, so canonical_type_parameter
10679 will not be able to find the canonical template
10680 template parameter for this level. Thus, we
10681 require structural equality checking to compare
10682 TEMPLATE_TEMPLATE_PARMs. */
10683 SET_TYPE_STRUCTURAL_EQUALITY (r);
10684 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10685 SET_TYPE_STRUCTURAL_EQUALITY (r);
10687 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10689 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10691 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10692 complain, in_decl);
10693 if (argvec == error_mark_node)
10694 return error_mark_node;
10696 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10697 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10702 case TEMPLATE_PARM_INDEX:
10703 r = reduce_template_parm_level (t, type, levels, args, complain);
10707 gcc_unreachable ();
10715 tree purpose, value, chain;
10717 if (t == void_list_node)
10720 purpose = TREE_PURPOSE (t);
10723 purpose = tsubst (purpose, args, complain, in_decl);
10724 if (purpose == error_mark_node)
10725 return error_mark_node;
10727 value = TREE_VALUE (t);
10730 value = tsubst (value, args, complain, in_decl);
10731 if (value == error_mark_node)
10732 return error_mark_node;
10734 chain = TREE_CHAIN (t);
10735 if (chain && chain != void_type_node)
10737 chain = tsubst (chain, args, complain, in_decl);
10738 if (chain == error_mark_node)
10739 return error_mark_node;
10741 if (purpose == TREE_PURPOSE (t)
10742 && value == TREE_VALUE (t)
10743 && chain == TREE_CHAIN (t))
10745 return hash_tree_cons (purpose, value, chain);
10749 /* We should never be tsubsting a binfo. */
10750 gcc_unreachable ();
10753 /* A vector of template arguments. */
10754 gcc_assert (!type);
10755 return tsubst_template_args (t, args, complain, in_decl);
10758 case REFERENCE_TYPE:
10760 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10765 Type deduction may fail for any of the following
10768 -- Attempting to create a pointer to reference type.
10769 -- Attempting to create a reference to a reference type or
10770 a reference to void.
10772 Core issue 106 says that creating a reference to a reference
10773 during instantiation is no longer a cause for failure. We
10774 only enforce this check in strict C++98 mode. */
10775 if ((TREE_CODE (type) == REFERENCE_TYPE
10776 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10777 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10779 static location_t last_loc;
10781 /* We keep track of the last time we issued this error
10782 message to avoid spewing a ton of messages during a
10783 single bad template instantiation. */
10784 if (complain & tf_error
10785 && last_loc != input_location)
10787 if (TREE_CODE (type) == VOID_TYPE)
10788 error ("forming reference to void");
10789 else if (code == POINTER_TYPE)
10790 error ("forming pointer to reference type %qT", type);
10792 error ("forming reference to reference type %qT", type);
10793 last_loc = input_location;
10796 return error_mark_node;
10798 else if (code == POINTER_TYPE)
10800 r = build_pointer_type (type);
10801 if (TREE_CODE (type) == METHOD_TYPE)
10802 r = build_ptrmemfunc_type (r);
10804 else if (TREE_CODE (type) == REFERENCE_TYPE)
10805 /* In C++0x, during template argument substitution, when there is an
10806 attempt to create a reference to a reference type, reference
10807 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10809 "If a template-argument for a template-parameter T names a type
10810 that is a reference to a type A, an attempt to create the type
10811 'lvalue reference to cv T' creates the type 'lvalue reference to
10812 A,' while an attempt to create the type type rvalue reference to
10813 cv T' creates the type T"
10815 r = cp_build_reference_type
10817 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10819 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10820 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10822 if (r != error_mark_node)
10823 /* Will this ever be needed for TYPE_..._TO values? */
10830 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10831 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10835 Type deduction may fail for any of the following
10838 -- Attempting to create "pointer to member of T" when T
10839 is not a class type. */
10840 if (complain & tf_error)
10841 error ("creating pointer to member of non-class type %qT", r);
10842 return error_mark_node;
10844 if (TREE_CODE (type) == REFERENCE_TYPE)
10846 if (complain & tf_error)
10847 error ("creating pointer to member reference type %qT", type);
10848 return error_mark_node;
10850 if (TREE_CODE (type) == VOID_TYPE)
10852 if (complain & tf_error)
10853 error ("creating pointer to member of type void");
10854 return error_mark_node;
10856 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10857 if (TREE_CODE (type) == FUNCTION_TYPE)
10859 /* The type of the implicit object parameter gets its
10860 cv-qualifiers from the FUNCTION_TYPE. */
10862 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10863 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10864 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10868 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10872 case FUNCTION_TYPE:
10877 fntype = tsubst_function_type (t, args, complain, in_decl);
10878 if (fntype == error_mark_node)
10879 return error_mark_node;
10881 /* Substitute the exception specification. */
10882 specs = tsubst_exception_specification (t, args, complain,
10884 if (specs == error_mark_node)
10885 return error_mark_node;
10887 fntype = build_exception_variant (fntype, specs);
10892 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10893 if (domain == error_mark_node)
10894 return error_mark_node;
10896 /* As an optimization, we avoid regenerating the array type if
10897 it will obviously be the same as T. */
10898 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10901 /* These checks should match the ones in grokdeclarator.
10905 The deduction may fail for any of the following reasons:
10907 -- Attempting to create an array with an element type that
10908 is void, a function type, or a reference type, or [DR337]
10909 an abstract class type. */
10910 if (TREE_CODE (type) == VOID_TYPE
10911 || TREE_CODE (type) == FUNCTION_TYPE
10912 || TREE_CODE (type) == REFERENCE_TYPE)
10914 if (complain & tf_error)
10915 error ("creating array of %qT", type);
10916 return error_mark_node;
10918 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10920 if (complain & tf_error)
10921 error ("creating array of %qT, which is an abstract class type",
10923 return error_mark_node;
10926 r = build_cplus_array_type (type, domain);
10928 if (TYPE_USER_ALIGN (t))
10930 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10931 TYPE_USER_ALIGN (r) = 1;
10937 case TYPENAME_TYPE:
10939 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10940 in_decl, /*entering_scope=*/1);
10941 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10942 complain, in_decl);
10944 if (ctx == error_mark_node || f == error_mark_node)
10945 return error_mark_node;
10947 if (!MAYBE_CLASS_TYPE_P (ctx))
10949 if (complain & tf_error)
10950 error ("%qT is not a class, struct, or union type", ctx);
10951 return error_mark_node;
10953 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10955 /* Normally, make_typename_type does not require that the CTX
10956 have complete type in order to allow things like:
10958 template <class T> struct S { typename S<T>::X Y; };
10960 But, such constructs have already been resolved by this
10961 point, so here CTX really should have complete type, unless
10962 it's a partial instantiation. */
10963 ctx = complete_type (ctx);
10964 if (!COMPLETE_TYPE_P (ctx))
10966 if (complain & tf_error)
10967 cxx_incomplete_type_error (NULL_TREE, ctx);
10968 return error_mark_node;
10972 f = make_typename_type (ctx, f, typename_type,
10973 (complain & tf_error) | tf_keep_type_decl);
10974 if (f == error_mark_node)
10976 if (TREE_CODE (f) == TYPE_DECL)
10978 complain |= tf_ignore_bad_quals;
10982 if (TREE_CODE (f) != TYPENAME_TYPE)
10984 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10986 if (complain & tf_error)
10987 error ("%qT resolves to %qT, which is not an enumeration type",
10990 return error_mark_node;
10992 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10994 if (complain & tf_error)
10995 error ("%qT resolves to %qT, which is is not a class type",
10998 return error_mark_node;
11002 return cp_build_qualified_type_real
11003 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11006 case UNBOUND_CLASS_TEMPLATE:
11008 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11009 in_decl, /*entering_scope=*/1);
11010 tree name = TYPE_IDENTIFIER (t);
11011 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11013 if (ctx == error_mark_node || name == error_mark_node)
11014 return error_mark_node;
11017 parm_list = tsubst_template_parms (parm_list, args, complain);
11018 return make_unbound_class_template (ctx, name, parm_list, complain);
11025 ++cp_unevaluated_operand;
11026 ++c_inhibit_evaluation_warnings;
11028 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11030 /*integral_constant_expression_p=*/false);
11032 --cp_unevaluated_operand;
11033 --c_inhibit_evaluation_warnings;
11035 type = finish_typeof (type);
11036 return cp_build_qualified_type_real (type,
11038 | cp_type_quals (type),
11042 case DECLTYPE_TYPE:
11046 ++cp_unevaluated_operand;
11047 ++c_inhibit_evaluation_warnings;
11049 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11051 /*integral_constant_expression_p=*/false);
11053 --cp_unevaluated_operand;
11054 --c_inhibit_evaluation_warnings;
11056 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11057 type = lambda_capture_field_type (type);
11058 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
11059 type = lambda_return_type (type);
11061 type = finish_decltype_type
11062 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11063 return cp_build_qualified_type_real (type,
11065 | cp_type_quals (type),
11069 case UNDERLYING_TYPE:
11071 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11072 complain, in_decl);
11073 return finish_underlying_type (type);
11076 case TYPE_ARGUMENT_PACK:
11077 case NONTYPE_ARGUMENT_PACK:
11079 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11081 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11085 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11087 /* For template nontype argument packs, also substitute into
11089 if (code == NONTYPE_ARGUMENT_PACK)
11090 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11108 /* We should use one of the expression tsubsts for these codes. */
11109 gcc_unreachable ();
11112 sorry ("use of %qs in template", tree_code_name [(int) code]);
11113 return error_mark_node;
11117 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11118 type of the expression on the left-hand side of the "." or "->"
11122 tsubst_baselink (tree baselink, tree object_type,
11123 tree args, tsubst_flags_t complain, tree in_decl)
11126 tree qualifying_scope;
11129 tree template_args = 0;
11130 bool template_id_p = false;
11132 /* A baselink indicates a function from a base class. Both the
11133 BASELINK_ACCESS_BINFO and the base class referenced may
11134 indicate bases of the template class, rather than the
11135 instantiated class. In addition, lookups that were not
11136 ambiguous before may be ambiguous now. Therefore, we perform
11137 the lookup again. */
11138 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11139 qualifying_scope = tsubst (qualifying_scope, args,
11140 complain, in_decl);
11141 fns = BASELINK_FUNCTIONS (baselink);
11142 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11143 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11145 template_id_p = true;
11146 template_args = TREE_OPERAND (fns, 1);
11147 fns = TREE_OPERAND (fns, 0);
11149 template_args = tsubst_template_args (template_args, args,
11150 complain, in_decl);
11152 name = DECL_NAME (get_first_fn (fns));
11153 if (IDENTIFIER_TYPENAME_P (name))
11154 name = mangle_conv_op_name_for_type (optype);
11155 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11157 return error_mark_node;
11159 /* If lookup found a single function, mark it as used at this
11160 point. (If it lookup found multiple functions the one selected
11161 later by overload resolution will be marked as used at that
11163 if (BASELINK_P (baselink))
11164 fns = BASELINK_FUNCTIONS (baselink);
11165 if (!template_id_p && !really_overloaded_fn (fns))
11166 mark_used (OVL_CURRENT (fns));
11168 /* Add back the template arguments, if present. */
11169 if (BASELINK_P (baselink) && template_id_p)
11170 BASELINK_FUNCTIONS (baselink)
11171 = build_nt (TEMPLATE_ID_EXPR,
11172 BASELINK_FUNCTIONS (baselink),
11174 /* Update the conversion operator type. */
11175 BASELINK_OPTYPE (baselink) = optype;
11178 object_type = current_class_type;
11179 return adjust_result_of_qualified_name_lookup (baselink,
11184 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11185 true if the qualified-id will be a postfix-expression in-and-of
11186 itself; false if more of the postfix-expression follows the
11187 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11191 tsubst_qualified_id (tree qualified_id, tree args,
11192 tsubst_flags_t complain, tree in_decl,
11193 bool done, bool address_p)
11199 tree template_args;
11201 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11203 /* Figure out what name to look up. */
11204 name = TREE_OPERAND (qualified_id, 1);
11205 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11207 is_template = true;
11208 template_args = TREE_OPERAND (name, 1);
11210 template_args = tsubst_template_args (template_args, args,
11211 complain, in_decl);
11212 name = TREE_OPERAND (name, 0);
11216 is_template = false;
11217 template_args = NULL_TREE;
11220 /* Substitute into the qualifying scope. When there are no ARGS, we
11221 are just trying to simplify a non-dependent expression. In that
11222 case the qualifying scope may be dependent, and, in any case,
11223 substituting will not help. */
11224 scope = TREE_OPERAND (qualified_id, 0);
11227 scope = tsubst (scope, args, complain, in_decl);
11228 expr = tsubst_copy (name, args, complain, in_decl);
11233 if (dependent_scope_p (scope))
11234 return build_qualified_name (NULL_TREE, scope, expr,
11235 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11237 if (!BASELINK_P (name) && !DECL_P (expr))
11239 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11241 /* A BIT_NOT_EXPR is used to represent a destructor. */
11242 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11244 error ("qualifying type %qT does not match destructor name ~%qT",
11245 scope, TREE_OPERAND (expr, 0));
11246 expr = error_mark_node;
11249 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11250 /*is_type_p=*/0, false);
11253 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11254 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11255 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11257 if (complain & tf_error)
11259 error ("dependent-name %qE is parsed as a non-type, but "
11260 "instantiation yields a type", qualified_id);
11261 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11263 return error_mark_node;
11269 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11271 /* Remember that there was a reference to this entity. */
11275 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11277 if (complain & tf_error)
11278 qualified_name_lookup_error (scope,
11279 TREE_OPERAND (qualified_id, 1),
11280 expr, input_location);
11281 return error_mark_node;
11285 expr = lookup_template_function (expr, template_args);
11287 if (expr == error_mark_node && complain & tf_error)
11288 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11289 expr, input_location);
11290 else if (TYPE_P (scope))
11292 expr = (adjust_result_of_qualified_name_lookup
11293 (expr, scope, current_class_type));
11294 expr = (finish_qualified_id_expr
11295 (scope, expr, done, address_p,
11296 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11297 /*template_arg_p=*/false));
11300 /* Expressions do not generally have reference type. */
11301 if (TREE_CODE (expr) != SCOPE_REF
11302 /* However, if we're about to form a pointer-to-member, we just
11303 want the referenced member referenced. */
11304 && TREE_CODE (expr) != OFFSET_REF)
11305 expr = convert_from_reference (expr);
11310 /* Like tsubst, but deals with expressions. This function just replaces
11311 template parms; to finish processing the resultant expression, use
11315 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11317 enum tree_code code;
11320 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11323 code = TREE_CODE (t);
11328 r = retrieve_local_specialization (t);
11333 /* This can happen for a parameter name used later in a function
11334 declaration (such as in a late-specified return type). Just
11335 make a dummy decl, since it's only used for its type. */
11336 gcc_assert (cp_unevaluated_operand != 0);
11337 /* We copy T because want to tsubst the PARM_DECL only,
11338 not the following PARM_DECLs that are chained to T. */
11340 r = tsubst_decl (c, args, complain);
11341 /* Give it the template pattern as its context; its true context
11342 hasn't been instantiated yet and this is good enough for
11344 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11347 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11348 r = ARGUMENT_PACK_SELECT_ARG (r);
11357 if (DECL_TEMPLATE_PARM_P (t))
11358 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11359 /* There is no need to substitute into namespace-scope
11361 if (DECL_NAMESPACE_SCOPE_P (t))
11363 /* If ARGS is NULL, then T is known to be non-dependent. */
11364 if (args == NULL_TREE)
11365 return integral_constant_value (t);
11367 /* Unfortunately, we cannot just call lookup_name here.
11370 template <int I> int f() {
11372 struct S { void g() { E e = a; } };
11375 When we instantiate f<7>::S::g(), say, lookup_name is not
11376 clever enough to find f<7>::a. */
11378 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11379 /*entering_scope=*/0);
11381 for (v = TYPE_VALUES (enum_type);
11383 v = TREE_CHAIN (v))
11384 if (TREE_PURPOSE (v) == DECL_NAME (t))
11385 return TREE_VALUE (v);
11387 /* We didn't find the name. That should never happen; if
11388 name-lookup found it during preliminary parsing, we
11389 should find it again here during instantiation. */
11390 gcc_unreachable ();
11395 if (DECL_CONTEXT (t))
11399 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11400 /*entering_scope=*/1);
11401 if (ctx != DECL_CONTEXT (t))
11403 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11406 if (complain & tf_error)
11407 error ("using invalid field %qD", t);
11408 return error_mark_node;
11417 case FUNCTION_DECL:
11418 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11419 || local_variable_p (t))
11420 t = tsubst (t, args, complain, in_decl);
11425 /* An OVERLOAD will always be a non-dependent overload set; an
11426 overload set from function scope will just be represented with an
11427 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11428 gcc_assert (!uses_template_parms (t));
11432 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11434 case TEMPLATE_DECL:
11435 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11436 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11437 args, complain, in_decl);
11438 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11439 return tsubst (t, args, complain, in_decl);
11440 else if (DECL_CLASS_SCOPE_P (t)
11441 && uses_template_parms (DECL_CONTEXT (t)))
11443 /* Template template argument like the following example need
11446 template <template <class> class TT> struct C {};
11447 template <class T> struct D {
11448 template <class U> struct E {};
11453 We are processing the template argument `E' in #1 for
11454 the template instantiation #2. Originally, `E' is a
11455 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11456 have to substitute this with one having context `D<int>'. */
11458 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11459 return lookup_field (context, DECL_NAME(t), 0, false);
11462 /* Ordinary template template argument. */
11466 case REINTERPRET_CAST_EXPR:
11467 case CONST_CAST_EXPR:
11468 case STATIC_CAST_EXPR:
11469 case DYNAMIC_CAST_EXPR:
11472 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11473 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11476 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11482 ++cp_unevaluated_operand;
11483 ++c_inhibit_evaluation_warnings;
11484 /* We only want to compute the number of arguments. */
11485 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11486 complain, in_decl);
11487 --cp_unevaluated_operand;
11488 --c_inhibit_evaluation_warnings;
11490 if (TREE_CODE (expanded) == TREE_VEC)
11491 len = TREE_VEC_LENGTH (expanded);
11493 if (expanded == error_mark_node)
11494 return error_mark_node;
11495 else if (PACK_EXPANSION_P (expanded)
11496 || (TREE_CODE (expanded) == TREE_VEC
11498 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11500 if (TREE_CODE (expanded) == TREE_VEC)
11501 expanded = TREE_VEC_ELT (expanded, len - 1);
11503 if (TYPE_P (expanded))
11504 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11505 complain & tf_error);
11507 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11508 complain & tf_error);
11511 return build_int_cst (size_type_node, len);
11517 case TRUTH_NOT_EXPR:
11520 case UNARY_PLUS_EXPR: /* Unary + */
11522 case AT_ENCODE_EXPR:
11526 case REALPART_EXPR:
11527 case IMAGPART_EXPR:
11529 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11530 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11532 case COMPONENT_REF:
11537 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11538 name = TREE_OPERAND (t, 1);
11539 if (TREE_CODE (name) == BIT_NOT_EXPR)
11541 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11542 complain, in_decl);
11543 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11545 else if (TREE_CODE (name) == SCOPE_REF
11546 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11548 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11549 complain, in_decl);
11550 name = TREE_OPERAND (name, 1);
11551 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11552 complain, in_decl);
11553 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11554 name = build_qualified_name (/*type=*/NULL_TREE,
11556 /*template_p=*/false);
11558 else if (TREE_CODE (name) == BASELINK)
11559 name = tsubst_baselink (name,
11560 non_reference (TREE_TYPE (object)),
11564 name = tsubst_copy (name, args, complain, in_decl);
11565 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11571 case TRUNC_DIV_EXPR:
11572 case CEIL_DIV_EXPR:
11573 case FLOOR_DIV_EXPR:
11574 case ROUND_DIV_EXPR:
11575 case EXACT_DIV_EXPR:
11579 case TRUNC_MOD_EXPR:
11580 case FLOOR_MOD_EXPR:
11581 case TRUTH_ANDIF_EXPR:
11582 case TRUTH_ORIF_EXPR:
11583 case TRUTH_AND_EXPR:
11584 case TRUTH_OR_EXPR:
11597 case COMPOUND_EXPR:
11600 case PREDECREMENT_EXPR:
11601 case PREINCREMENT_EXPR:
11602 case POSTDECREMENT_EXPR:
11603 case POSTINCREMENT_EXPR:
11605 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11606 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11609 return build_qualified_name (/*type=*/NULL_TREE,
11610 tsubst_copy (TREE_OPERAND (t, 0),
11611 args, complain, in_decl),
11612 tsubst_copy (TREE_OPERAND (t, 1),
11613 args, complain, in_decl),
11614 QUALIFIED_NAME_IS_TEMPLATE (t));
11619 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11620 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11621 NULL_TREE, NULL_TREE);
11625 int n = VL_EXP_OPERAND_LENGTH (t);
11626 tree result = build_vl_exp (CALL_EXPR, n);
11628 for (i = 0; i < n; i++)
11629 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11630 complain, in_decl);
11636 case PSEUDO_DTOR_EXPR:
11639 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11640 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11641 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11642 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11649 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11650 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11651 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11652 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11659 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11660 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11661 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11662 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11666 case TEMPLATE_ID_EXPR:
11668 /* Substituted template arguments */
11669 tree fn = TREE_OPERAND (t, 0);
11670 tree targs = TREE_OPERAND (t, 1);
11672 fn = tsubst_copy (fn, args, complain, in_decl);
11674 targs = tsubst_template_args (targs, args, complain, in_decl);
11676 return lookup_template_function (fn, targs);
11681 tree purpose, value, chain;
11683 if (t == void_list_node)
11686 purpose = TREE_PURPOSE (t);
11688 purpose = tsubst_copy (purpose, args, complain, in_decl);
11689 value = TREE_VALUE (t);
11691 value = tsubst_copy (value, args, complain, in_decl);
11692 chain = TREE_CHAIN (t);
11693 if (chain && chain != void_type_node)
11694 chain = tsubst_copy (chain, args, complain, in_decl);
11695 if (purpose == TREE_PURPOSE (t)
11696 && value == TREE_VALUE (t)
11697 && chain == TREE_CHAIN (t))
11699 return tree_cons (purpose, value, chain);
11704 case ENUMERAL_TYPE:
11706 case TEMPLATE_TYPE_PARM:
11707 case TEMPLATE_TEMPLATE_PARM:
11708 case BOUND_TEMPLATE_TEMPLATE_PARM:
11709 case TEMPLATE_PARM_INDEX:
11711 case REFERENCE_TYPE:
11713 case FUNCTION_TYPE:
11716 case TYPENAME_TYPE:
11717 case UNBOUND_CLASS_TEMPLATE:
11719 case DECLTYPE_TYPE:
11721 return tsubst (t, args, complain, in_decl);
11723 case IDENTIFIER_NODE:
11724 if (IDENTIFIER_TYPENAME_P (t))
11726 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11727 return mangle_conv_op_name_for_type (new_type);
11733 /* This is handled by tsubst_copy_and_build. */
11734 gcc_unreachable ();
11737 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11739 tsubst (TREE_TYPE (t), args, complain, in_decl));
11741 case CLEANUP_POINT_EXPR:
11742 /* We shouldn't have built any of these during initial template
11743 generation. Instead, they should be built during instantiation
11744 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11745 gcc_unreachable ();
11749 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11750 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11751 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11752 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11753 mark_used (TREE_OPERAND (r, 1));
11756 case EXPR_PACK_EXPANSION:
11757 error ("invalid use of pack expansion expression");
11758 return error_mark_node;
11760 case NONTYPE_ARGUMENT_PACK:
11761 error ("use %<...%> to expand argument pack");
11762 return error_mark_node;
11769 /* Instantiate any typedefs in the type. */
11770 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11771 r = fold_convert (type, t);
11772 gcc_assert (TREE_CODE (r) == code);
11777 /* These can sometimes show up in a partial instantiation, but never
11778 involve template parms. */
11779 gcc_assert (!uses_template_parms (t));
11783 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
11784 gcc_checking_assert (false);
11789 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11792 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11795 tree new_clauses = NULL, nc, oc;
11797 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11799 nc = copy_node (oc);
11800 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11803 switch (OMP_CLAUSE_CODE (nc))
11805 case OMP_CLAUSE_LASTPRIVATE:
11806 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11808 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11809 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11810 in_decl, /*integral_constant_expression_p=*/false);
11811 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11812 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11815 case OMP_CLAUSE_PRIVATE:
11816 case OMP_CLAUSE_SHARED:
11817 case OMP_CLAUSE_FIRSTPRIVATE:
11818 case OMP_CLAUSE_REDUCTION:
11819 case OMP_CLAUSE_COPYIN:
11820 case OMP_CLAUSE_COPYPRIVATE:
11821 case OMP_CLAUSE_IF:
11822 case OMP_CLAUSE_NUM_THREADS:
11823 case OMP_CLAUSE_SCHEDULE:
11824 case OMP_CLAUSE_COLLAPSE:
11825 OMP_CLAUSE_OPERAND (nc, 0)
11826 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11827 in_decl, /*integral_constant_expression_p=*/false);
11829 case OMP_CLAUSE_NOWAIT:
11830 case OMP_CLAUSE_ORDERED:
11831 case OMP_CLAUSE_DEFAULT:
11832 case OMP_CLAUSE_UNTIED:
11835 gcc_unreachable ();
11839 return finish_omp_clauses (nreverse (new_clauses));
11842 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11845 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11848 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11850 tree purpose, value, chain;
11855 if (TREE_CODE (t) != TREE_LIST)
11856 return tsubst_copy_and_build (t, args, complain, in_decl,
11857 /*function_p=*/false,
11858 /*integral_constant_expression_p=*/false);
11860 if (t == void_list_node)
11863 purpose = TREE_PURPOSE (t);
11865 purpose = RECUR (purpose);
11866 value = TREE_VALUE (t);
11867 if (value && TREE_CODE (value) != LABEL_DECL)
11868 value = RECUR (value);
11869 chain = TREE_CHAIN (t);
11870 if (chain && chain != void_type_node)
11871 chain = RECUR (chain);
11872 return tree_cons (purpose, value, chain);
11876 /* Substitute one OMP_FOR iterator. */
11879 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11880 tree condv, tree incrv, tree *clauses,
11881 tree args, tsubst_flags_t complain, tree in_decl,
11882 bool integral_constant_expression_p)
11884 #define RECUR(NODE) \
11885 tsubst_expr ((NODE), args, complain, in_decl, \
11886 integral_constant_expression_p)
11887 tree decl, init, cond, incr, auto_node;
11889 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11890 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11891 decl = RECUR (TREE_OPERAND (init, 0));
11892 init = TREE_OPERAND (init, 1);
11893 auto_node = type_uses_auto (TREE_TYPE (decl));
11894 if (auto_node && init)
11896 tree init_expr = init;
11897 if (TREE_CODE (init_expr) == DECL_EXPR)
11898 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11899 init_expr = RECUR (init_expr);
11901 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11903 gcc_assert (!type_dependent_expression_p (decl));
11905 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11907 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11908 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11909 if (TREE_CODE (incr) == MODIFY_EXPR)
11910 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11911 RECUR (TREE_OPERAND (incr, 1)),
11914 incr = RECUR (incr);
11915 TREE_VEC_ELT (declv, i) = decl;
11916 TREE_VEC_ELT (initv, i) = init;
11917 TREE_VEC_ELT (condv, i) = cond;
11918 TREE_VEC_ELT (incrv, i) = incr;
11922 if (init && TREE_CODE (init) != DECL_EXPR)
11925 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11927 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11928 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11929 && OMP_CLAUSE_DECL (c) == decl)
11931 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11932 && OMP_CLAUSE_DECL (c) == decl)
11933 error ("iteration variable %qD should not be firstprivate", decl);
11934 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11935 && OMP_CLAUSE_DECL (c) == decl)
11936 error ("iteration variable %qD should not be reduction", decl);
11940 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11941 OMP_CLAUSE_DECL (c) = decl;
11942 c = finish_omp_clauses (c);
11945 OMP_CLAUSE_CHAIN (c) = *clauses;
11950 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11951 if (COMPARISON_CLASS_P (cond))
11952 cond = build2 (TREE_CODE (cond), boolean_type_node,
11953 RECUR (TREE_OPERAND (cond, 0)),
11954 RECUR (TREE_OPERAND (cond, 1)));
11956 cond = RECUR (cond);
11957 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11958 switch (TREE_CODE (incr))
11960 case PREINCREMENT_EXPR:
11961 case PREDECREMENT_EXPR:
11962 case POSTINCREMENT_EXPR:
11963 case POSTDECREMENT_EXPR:
11964 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11965 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11968 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11969 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11971 tree rhs = TREE_OPERAND (incr, 1);
11972 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11973 RECUR (TREE_OPERAND (incr, 0)),
11974 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11975 RECUR (TREE_OPERAND (rhs, 0)),
11976 RECUR (TREE_OPERAND (rhs, 1))));
11979 incr = RECUR (incr);
11982 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11983 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11985 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11986 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11987 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11988 TREE_TYPE (decl), lhs,
11989 RECUR (TREE_OPERAND (incr, 2))));
11991 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11992 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11993 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11995 tree rhs = TREE_OPERAND (incr, 2);
11996 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11997 RECUR (TREE_OPERAND (incr, 0)),
11998 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11999 RECUR (TREE_OPERAND (rhs, 0)),
12000 RECUR (TREE_OPERAND (rhs, 1))));
12003 incr = RECUR (incr);
12006 incr = RECUR (incr);
12010 TREE_VEC_ELT (declv, i) = decl;
12011 TREE_VEC_ELT (initv, i) = init;
12012 TREE_VEC_ELT (condv, i) = cond;
12013 TREE_VEC_ELT (incrv, i) = incr;
12017 /* Like tsubst_copy for expressions, etc. but also does semantic
12021 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12022 bool integral_constant_expression_p)
12024 #define RECUR(NODE) \
12025 tsubst_expr ((NODE), args, complain, in_decl, \
12026 integral_constant_expression_p)
12030 if (t == NULL_TREE || t == error_mark_node)
12033 if (EXPR_HAS_LOCATION (t))
12034 input_location = EXPR_LOCATION (t);
12035 if (STATEMENT_CODE_P (TREE_CODE (t)))
12036 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12038 switch (TREE_CODE (t))
12040 case STATEMENT_LIST:
12042 tree_stmt_iterator i;
12043 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12044 RECUR (tsi_stmt (i));
12048 case CTOR_INITIALIZER:
12049 finish_mem_initializers (tsubst_initializer_list
12050 (TREE_OPERAND (t, 0), args));
12054 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12058 tmp = RECUR (EXPR_STMT_EXPR (t));
12059 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12060 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12062 finish_expr_stmt (tmp);
12066 do_using_directive (USING_STMT_NAMESPACE (t));
12071 tree decl, pattern_decl;
12074 pattern_decl = decl = DECL_EXPR_DECL (t);
12075 if (TREE_CODE (decl) == LABEL_DECL)
12076 finish_label_decl (DECL_NAME (decl));
12077 else if (TREE_CODE (decl) == USING_DECL)
12079 tree scope = USING_DECL_SCOPE (decl);
12080 tree name = DECL_NAME (decl);
12083 scope = tsubst (scope, args, complain, in_decl);
12084 decl = lookup_qualified_name (scope, name,
12085 /*is_type_p=*/false,
12086 /*complain=*/false);
12087 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12088 qualified_name_lookup_error (scope, name, decl, input_location);
12090 do_local_using_decl (decl, scope, name);
12094 init = DECL_INITIAL (decl);
12095 decl = tsubst (decl, args, complain, in_decl);
12096 if (decl != error_mark_node)
12098 /* By marking the declaration as instantiated, we avoid
12099 trying to instantiate it. Since instantiate_decl can't
12100 handle local variables, and since we've already done
12101 all that needs to be done, that's the right thing to
12103 if (TREE_CODE (decl) == VAR_DECL)
12104 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12105 if (TREE_CODE (decl) == VAR_DECL
12106 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12107 /* Anonymous aggregates are a special case. */
12108 finish_anon_union (decl);
12111 int const_init = false;
12112 maybe_push_decl (decl);
12113 if (TREE_CODE (decl) == VAR_DECL
12114 && DECL_PRETTY_FUNCTION_P (decl))
12116 /* For __PRETTY_FUNCTION__ we have to adjust the
12118 const char *const name
12119 = cxx_printable_name (current_function_decl, 2);
12120 init = cp_fname_init (name, &TREE_TYPE (decl));
12124 tree t = RECUR (init);
12128 /* If we had an initializer but it
12129 instantiated to nothing,
12130 value-initialize the object. This will
12131 only occur when the initializer was a
12132 pack expansion where the parameter packs
12133 used in that expansion were of length
12135 init = build_value_init (TREE_TYPE (decl),
12137 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12138 init = get_target_expr_sfinae (init, complain);
12144 if (TREE_CODE (decl) == VAR_DECL)
12145 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12147 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12152 /* A DECL_EXPR can also be used as an expression, in the condition
12153 clause of an if/for/while construct. */
12158 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12159 RECUR (FOR_INIT_STMT (t));
12160 finish_for_init_stmt (stmt);
12161 tmp = RECUR (FOR_COND (t));
12162 finish_for_cond (tmp, stmt);
12163 tmp = RECUR (FOR_EXPR (t));
12164 finish_for_expr (tmp, stmt);
12165 RECUR (FOR_BODY (t));
12166 finish_for_stmt (stmt);
12169 case RANGE_FOR_STMT:
12172 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12173 decl = RANGE_FOR_DECL (t);
12174 decl = tsubst (decl, args, complain, in_decl);
12175 maybe_push_decl (decl);
12176 expr = RECUR (RANGE_FOR_EXPR (t));
12177 stmt = cp_convert_range_for (stmt, decl, expr);
12178 RECUR (RANGE_FOR_BODY (t));
12179 finish_for_stmt (stmt);
12184 stmt = begin_while_stmt ();
12185 tmp = RECUR (WHILE_COND (t));
12186 finish_while_stmt_cond (tmp, stmt);
12187 RECUR (WHILE_BODY (t));
12188 finish_while_stmt (stmt);
12192 stmt = begin_do_stmt ();
12193 RECUR (DO_BODY (t));
12194 finish_do_body (stmt);
12195 tmp = RECUR (DO_COND (t));
12196 finish_do_stmt (tmp, stmt);
12200 stmt = begin_if_stmt ();
12201 tmp = RECUR (IF_COND (t));
12202 finish_if_stmt_cond (tmp, stmt);
12203 RECUR (THEN_CLAUSE (t));
12204 finish_then_clause (stmt);
12206 if (ELSE_CLAUSE (t))
12208 begin_else_clause (stmt);
12209 RECUR (ELSE_CLAUSE (t));
12210 finish_else_clause (stmt);
12213 finish_if_stmt (stmt);
12217 if (BIND_EXPR_BODY_BLOCK (t))
12218 stmt = begin_function_body ();
12220 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12221 ? BCS_TRY_BLOCK : 0);
12223 RECUR (BIND_EXPR_BODY (t));
12225 if (BIND_EXPR_BODY_BLOCK (t))
12226 finish_function_body (stmt);
12228 finish_compound_stmt (stmt);
12232 finish_break_stmt ();
12235 case CONTINUE_STMT:
12236 finish_continue_stmt ();
12240 stmt = begin_switch_stmt ();
12241 tmp = RECUR (SWITCH_STMT_COND (t));
12242 finish_switch_cond (tmp, stmt);
12243 RECUR (SWITCH_STMT_BODY (t));
12244 finish_switch_stmt (stmt);
12247 case CASE_LABEL_EXPR:
12248 finish_case_label (EXPR_LOCATION (t),
12249 RECUR (CASE_LOW (t)),
12250 RECUR (CASE_HIGH (t)));
12255 tree decl = LABEL_EXPR_LABEL (t);
12258 label = finish_label_stmt (DECL_NAME (decl));
12259 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12260 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12265 tmp = GOTO_DESTINATION (t);
12266 if (TREE_CODE (tmp) != LABEL_DECL)
12267 /* Computed goto's must be tsubst'd into. On the other hand,
12268 non-computed gotos must not be; the identifier in question
12269 will have no binding. */
12272 tmp = DECL_NAME (tmp);
12273 finish_goto_stmt (tmp);
12277 tmp = finish_asm_stmt
12278 (ASM_VOLATILE_P (t),
12279 RECUR (ASM_STRING (t)),
12280 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12281 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12282 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12283 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12285 tree asm_expr = tmp;
12286 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12287 asm_expr = TREE_OPERAND (asm_expr, 0);
12288 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12295 stmt = begin_try_block ();
12296 RECUR (TRY_STMTS (t));
12297 finish_cleanup_try_block (stmt);
12298 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12302 tree compound_stmt = NULL_TREE;
12304 if (FN_TRY_BLOCK_P (t))
12305 stmt = begin_function_try_block (&compound_stmt);
12307 stmt = begin_try_block ();
12309 RECUR (TRY_STMTS (t));
12311 if (FN_TRY_BLOCK_P (t))
12312 finish_function_try_block (stmt);
12314 finish_try_block (stmt);
12316 RECUR (TRY_HANDLERS (t));
12317 if (FN_TRY_BLOCK_P (t))
12318 finish_function_handler_sequence (stmt, compound_stmt);
12320 finish_handler_sequence (stmt);
12326 tree decl = HANDLER_PARMS (t);
12330 decl = tsubst (decl, args, complain, in_decl);
12331 /* Prevent instantiate_decl from trying to instantiate
12332 this variable. We've already done all that needs to be
12334 if (decl != error_mark_node)
12335 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12337 stmt = begin_handler ();
12338 finish_handler_parms (decl, stmt);
12339 RECUR (HANDLER_BODY (t));
12340 finish_handler (stmt);
12345 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12348 case STATIC_ASSERT:
12351 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12354 /*integral_constant_expression_p=*/true);
12355 finish_static_assert (condition,
12356 STATIC_ASSERT_MESSAGE (t),
12357 STATIC_ASSERT_SOURCE_LOCATION (t),
12358 /*member_p=*/false);
12363 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12364 args, complain, in_decl);
12365 stmt = begin_omp_parallel ();
12366 RECUR (OMP_PARALLEL_BODY (t));
12367 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12368 = OMP_PARALLEL_COMBINED (t);
12372 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12373 args, complain, in_decl);
12374 stmt = begin_omp_task ();
12375 RECUR (OMP_TASK_BODY (t));
12376 finish_omp_task (tmp, stmt);
12381 tree clauses, body, pre_body;
12382 tree declv, initv, condv, incrv;
12385 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12386 args, complain, in_decl);
12387 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12388 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12389 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12390 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12392 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12393 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12394 &clauses, args, complain, in_decl,
12395 integral_constant_expression_p);
12397 stmt = begin_omp_structured_block ();
12399 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12400 if (TREE_VEC_ELT (initv, i) == NULL
12401 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12402 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12403 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12405 tree init = RECUR (TREE_VEC_ELT (initv, i));
12406 gcc_assert (init == TREE_VEC_ELT (declv, i));
12407 TREE_VEC_ELT (initv, i) = NULL_TREE;
12411 tree decl_expr = TREE_VEC_ELT (initv, i);
12412 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12413 gcc_assert (init != NULL);
12414 TREE_VEC_ELT (initv, i) = RECUR (init);
12415 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12417 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12420 pre_body = push_stmt_list ();
12421 RECUR (OMP_FOR_PRE_BODY (t));
12422 pre_body = pop_stmt_list (pre_body);
12424 body = push_stmt_list ();
12425 RECUR (OMP_FOR_BODY (t));
12426 body = pop_stmt_list (body);
12428 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12429 body, pre_body, clauses);
12431 add_stmt (finish_omp_structured_block (stmt));
12437 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12438 stmt = push_stmt_list ();
12439 RECUR (OMP_BODY (t));
12440 stmt = pop_stmt_list (stmt);
12443 OMP_BODY (t) = stmt;
12444 OMP_CLAUSES (t) = tmp;
12452 stmt = push_stmt_list ();
12453 RECUR (OMP_BODY (t));
12454 stmt = pop_stmt_list (stmt);
12457 OMP_BODY (t) = stmt;
12462 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12464 tree op1 = TREE_OPERAND (t, 1);
12465 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12466 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12467 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12471 case EXPR_PACK_EXPANSION:
12472 error ("invalid use of pack expansion expression");
12473 return error_mark_node;
12475 case NONTYPE_ARGUMENT_PACK:
12476 error ("use %<...%> to expand argument pack");
12477 return error_mark_node;
12480 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12482 return tsubst_copy_and_build (t, args, complain, in_decl,
12483 /*function_p=*/false,
12484 integral_constant_expression_p);
12491 /* T is a postfix-expression that is not being used in a function
12492 call. Return the substituted version of T. */
12495 tsubst_non_call_postfix_expression (tree t, tree args,
12496 tsubst_flags_t complain,
12499 if (TREE_CODE (t) == SCOPE_REF)
12500 t = tsubst_qualified_id (t, args, complain, in_decl,
12501 /*done=*/false, /*address_p=*/false);
12503 t = tsubst_copy_and_build (t, args, complain, in_decl,
12504 /*function_p=*/false,
12505 /*integral_constant_expression_p=*/false);
12510 /* Like tsubst but deals with expressions and performs semantic
12511 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12514 tsubst_copy_and_build (tree t,
12516 tsubst_flags_t complain,
12519 bool integral_constant_expression_p)
12521 #define RECUR(NODE) \
12522 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12523 /*function_p=*/false, \
12524 integral_constant_expression_p)
12528 if (t == NULL_TREE || t == error_mark_node)
12531 switch (TREE_CODE (t))
12535 /* Fall through. */
12536 case IDENTIFIER_NODE:
12540 bool non_integral_constant_expression_p;
12541 const char *error_msg;
12543 if (IDENTIFIER_TYPENAME_P (t))
12545 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12546 t = mangle_conv_op_name_for_type (new_type);
12549 /* Look up the name. */
12550 decl = lookup_name (t);
12552 /* By convention, expressions use ERROR_MARK_NODE to indicate
12553 failure, not NULL_TREE. */
12554 if (decl == NULL_TREE)
12555 decl = error_mark_node;
12557 decl = finish_id_expression (t, decl, NULL_TREE,
12559 integral_constant_expression_p,
12560 /*allow_non_integral_constant_expression_p=*/false,
12561 &non_integral_constant_expression_p,
12562 /*template_p=*/false,
12564 /*address_p=*/false,
12565 /*template_arg_p=*/false,
12570 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12571 decl = unqualified_name_lookup_error (decl);
12575 case TEMPLATE_ID_EXPR:
12578 tree templ = RECUR (TREE_OPERAND (t, 0));
12579 tree targs = TREE_OPERAND (t, 1);
12582 targs = tsubst_template_args (targs, args, complain, in_decl);
12584 if (TREE_CODE (templ) == COMPONENT_REF)
12586 object = TREE_OPERAND (templ, 0);
12587 templ = TREE_OPERAND (templ, 1);
12590 object = NULL_TREE;
12591 templ = lookup_template_function (templ, targs);
12594 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12595 object, templ, NULL_TREE);
12597 return baselink_for_fns (templ);
12602 tree r = RECUR (TREE_OPERAND (t, 0));
12604 if (REFERENCE_REF_P (t))
12606 /* A type conversion to reference type will be enclosed in
12607 such an indirect ref, but the substitution of the cast
12608 will have also added such an indirect ref. */
12609 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12610 r = convert_from_reference (r);
12613 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12619 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12620 RECUR (TREE_OPERAND (t, 0)));
12623 case REINTERPRET_CAST_EXPR:
12624 case CONST_CAST_EXPR:
12625 case DYNAMIC_CAST_EXPR:
12626 case STATIC_CAST_EXPR:
12631 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12632 if (integral_constant_expression_p
12633 && !cast_valid_in_integral_constant_expression_p (type))
12635 if (complain & tf_error)
12636 error ("a cast to a type other than an integral or "
12637 "enumeration type cannot appear in a constant-expression");
12638 return error_mark_node;
12641 op = RECUR (TREE_OPERAND (t, 0));
12643 switch (TREE_CODE (t))
12646 return build_functional_cast (type, op, complain);
12647 case REINTERPRET_CAST_EXPR:
12648 return build_reinterpret_cast (type, op, complain);
12649 case CONST_CAST_EXPR:
12650 return build_const_cast (type, op, complain);
12651 case DYNAMIC_CAST_EXPR:
12652 return build_dynamic_cast (type, op, complain);
12653 case STATIC_CAST_EXPR:
12654 return build_static_cast (type, op, complain);
12656 gcc_unreachable ();
12660 case POSTDECREMENT_EXPR:
12661 case POSTINCREMENT_EXPR:
12662 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12663 args, complain, in_decl);
12664 return build_x_unary_op (TREE_CODE (t), op1, complain);
12666 case PREDECREMENT_EXPR:
12667 case PREINCREMENT_EXPR:
12671 case TRUTH_NOT_EXPR:
12672 case UNARY_PLUS_EXPR: /* Unary + */
12673 case REALPART_EXPR:
12674 case IMAGPART_EXPR:
12675 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12679 op1 = TREE_OPERAND (t, 0);
12680 if (TREE_CODE (op1) == LABEL_DECL)
12681 return finish_label_address_expr (DECL_NAME (op1),
12682 EXPR_LOCATION (op1));
12683 if (TREE_CODE (op1) == SCOPE_REF)
12684 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12685 /*done=*/true, /*address_p=*/true);
12687 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12689 return build_x_unary_op (ADDR_EXPR, op1, complain);
12694 case TRUNC_DIV_EXPR:
12695 case CEIL_DIV_EXPR:
12696 case FLOOR_DIV_EXPR:
12697 case ROUND_DIV_EXPR:
12698 case EXACT_DIV_EXPR:
12702 case TRUNC_MOD_EXPR:
12703 case FLOOR_MOD_EXPR:
12704 case TRUTH_ANDIF_EXPR:
12705 case TRUTH_ORIF_EXPR:
12706 case TRUTH_AND_EXPR:
12707 case TRUTH_OR_EXPR:
12722 return build_x_binary_op
12724 RECUR (TREE_OPERAND (t, 0)),
12725 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12727 : TREE_CODE (TREE_OPERAND (t, 0))),
12728 RECUR (TREE_OPERAND (t, 1)),
12729 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12731 : TREE_CODE (TREE_OPERAND (t, 1))),
12732 /*overloaded_p=*/NULL,
12736 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12737 /*address_p=*/false);
12739 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12740 args, complain, in_decl);
12741 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12744 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12745 return tsubst_copy (t, args, complain, in_decl);
12749 op1 = TREE_OPERAND (t, 0);
12752 /* When there are no ARGS, we are trying to evaluate a
12753 non-dependent expression from the parser. Trying to do
12754 the substitutions may not work. */
12756 op1 = TREE_TYPE (op1);
12760 ++cp_unevaluated_operand;
12761 ++c_inhibit_evaluation_warnings;
12762 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12763 /*function_p=*/false,
12764 /*integral_constant_expression_p=*/false);
12765 --cp_unevaluated_operand;
12766 --c_inhibit_evaluation_warnings;
12769 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12770 complain & tf_error);
12772 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12773 complain & tf_error);
12775 case AT_ENCODE_EXPR:
12777 op1 = TREE_OPERAND (t, 0);
12778 ++cp_unevaluated_operand;
12779 ++c_inhibit_evaluation_warnings;
12780 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12781 /*function_p=*/false,
12782 /*integral_constant_expression_p=*/false);
12783 --cp_unevaluated_operand;
12784 --c_inhibit_evaluation_warnings;
12785 return objc_build_encode_expr (op1);
12788 case NOEXCEPT_EXPR:
12789 op1 = TREE_OPERAND (t, 0);
12790 ++cp_unevaluated_operand;
12791 ++c_inhibit_evaluation_warnings;
12792 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12793 /*function_p=*/false,
12794 /*integral_constant_expression_p=*/false);
12795 --cp_unevaluated_operand;
12796 --c_inhibit_evaluation_warnings;
12797 return finish_noexcept_expr (op1, complain);
12801 tree r = build_x_modify_expr
12802 (RECUR (TREE_OPERAND (t, 0)),
12803 TREE_CODE (TREE_OPERAND (t, 1)),
12804 RECUR (TREE_OPERAND (t, 2)),
12806 /* TREE_NO_WARNING must be set if either the expression was
12807 parenthesized or it uses an operator such as >>= rather
12808 than plain assignment. In the former case, it was already
12809 set and must be copied. In the latter case,
12810 build_x_modify_expr sets it and it must not be reset
12812 if (TREE_NO_WARNING (t))
12813 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12818 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12819 args, complain, in_decl);
12820 /* Remember that there was a reference to this entity. */
12823 return build_x_arrow (op1);
12827 tree placement = RECUR (TREE_OPERAND (t, 0));
12828 tree init = RECUR (TREE_OPERAND (t, 3));
12829 VEC(tree,gc) *placement_vec;
12830 VEC(tree,gc) *init_vec;
12833 if (placement == NULL_TREE)
12834 placement_vec = NULL;
12837 placement_vec = make_tree_vector ();
12838 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12839 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12842 /* If there was an initializer in the original tree, but it
12843 instantiated to an empty list, then we should pass a
12844 non-NULL empty vector to tell build_new that it was an
12845 empty initializer() rather than no initializer. This can
12846 only happen when the initializer is a pack expansion whose
12847 parameter packs are of length zero. */
12848 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12852 init_vec = make_tree_vector ();
12853 if (init == void_zero_node)
12854 gcc_assert (init_vec != NULL);
12857 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12858 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12862 ret = build_new (&placement_vec,
12863 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
12864 RECUR (TREE_OPERAND (t, 2)),
12866 NEW_EXPR_USE_GLOBAL (t),
12869 if (placement_vec != NULL)
12870 release_tree_vector (placement_vec);
12871 if (init_vec != NULL)
12872 release_tree_vector (init_vec);
12878 return delete_sanity
12879 (RECUR (TREE_OPERAND (t, 0)),
12880 RECUR (TREE_OPERAND (t, 1)),
12881 DELETE_EXPR_USE_VEC (t),
12882 DELETE_EXPR_USE_GLOBAL (t),
12885 case COMPOUND_EXPR:
12886 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12887 RECUR (TREE_OPERAND (t, 1)),
12893 VEC(tree,gc) *call_args;
12894 unsigned int nargs, i;
12899 function = CALL_EXPR_FN (t);
12900 /* When we parsed the expression, we determined whether or
12901 not Koenig lookup should be performed. */
12902 koenig_p = KOENIG_LOOKUP_P (t);
12903 if (TREE_CODE (function) == SCOPE_REF)
12905 qualified_p = true;
12906 function = tsubst_qualified_id (function, args, complain, in_decl,
12908 /*address_p=*/false);
12910 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
12912 /* Do nothing; calling tsubst_copy_and_build on an identifier
12913 would incorrectly perform unqualified lookup again.
12915 Note that we can also have an IDENTIFIER_NODE if the earlier
12916 unqualified lookup found a member function; in that case
12917 koenig_p will be false and we do want to do the lookup
12918 again to find the instantiated member function.
12920 FIXME but doing that causes c++/15272, so we need to stop
12921 using IDENTIFIER_NODE in that situation. */
12922 qualified_p = false;
12926 if (TREE_CODE (function) == COMPONENT_REF)
12928 tree op = TREE_OPERAND (function, 1);
12930 qualified_p = (TREE_CODE (op) == SCOPE_REF
12931 || (BASELINK_P (op)
12932 && BASELINK_QUALIFIED_P (op)));
12935 qualified_p = false;
12937 function = tsubst_copy_and_build (function, args, complain,
12940 integral_constant_expression_p);
12942 if (BASELINK_P (function))
12943 qualified_p = true;
12946 nargs = call_expr_nargs (t);
12947 call_args = make_tree_vector ();
12948 for (i = 0; i < nargs; ++i)
12950 tree arg = CALL_EXPR_ARG (t, i);
12952 if (!PACK_EXPANSION_P (arg))
12953 VEC_safe_push (tree, gc, call_args,
12954 RECUR (CALL_EXPR_ARG (t, i)));
12957 /* Expand the pack expansion and push each entry onto
12959 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12960 if (TREE_CODE (arg) == TREE_VEC)
12962 unsigned int len, j;
12964 len = TREE_VEC_LENGTH (arg);
12965 for (j = 0; j < len; ++j)
12967 tree value = TREE_VEC_ELT (arg, j);
12968 if (value != NULL_TREE)
12969 value = convert_from_reference (value);
12970 VEC_safe_push (tree, gc, call_args, value);
12975 /* A partial substitution. Add one entry. */
12976 VEC_safe_push (tree, gc, call_args, arg);
12981 /* We do not perform argument-dependent lookup if normal
12982 lookup finds a non-function, in accordance with the
12983 expected resolution of DR 218. */
12985 && ((is_overloaded_fn (function)
12986 /* If lookup found a member function, the Koenig lookup is
12987 not appropriate, even if an unqualified-name was used
12988 to denote the function. */
12989 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12990 || TREE_CODE (function) == IDENTIFIER_NODE)
12991 /* Only do this when substitution turns a dependent call
12992 into a non-dependent call. */
12993 && type_dependent_expression_p_push (t)
12994 && !any_type_dependent_arguments_p (call_args))
12995 function = perform_koenig_lookup (function, call_args, false,
12998 if (TREE_CODE (function) == IDENTIFIER_NODE
12999 && !any_type_dependent_arguments_p (call_args))
13001 if (koenig_p && (complain & tf_warning_or_error))
13003 /* For backwards compatibility and good diagnostics, try
13004 the unqualified lookup again if we aren't in SFINAE
13006 tree unq = (tsubst_copy_and_build
13007 (function, args, complain, in_decl, true,
13008 integral_constant_expression_p));
13009 if (unq != function)
13012 if (TREE_CODE (fn) == COMPONENT_REF)
13013 fn = TREE_OPERAND (fn, 1);
13014 if (is_overloaded_fn (fn))
13015 fn = get_first_fn (fn);
13016 permerror (EXPR_LOC_OR_HERE (t),
13017 "%qD was not declared in this scope, "
13018 "and no declarations were found by "
13019 "argument-dependent lookup at the point "
13020 "of instantiation", function);
13021 if (DECL_CLASS_SCOPE_P (fn))
13023 inform (EXPR_LOC_OR_HERE (t),
13024 "declarations in dependent base %qT are "
13025 "not found by unqualified lookup",
13026 DECL_CLASS_CONTEXT (fn));
13027 if (current_class_ptr)
13028 inform (EXPR_LOC_OR_HERE (t),
13029 "use %<this->%D%> instead", function);
13031 inform (EXPR_LOC_OR_HERE (t),
13032 "use %<%T::%D%> instead",
13033 current_class_name, function);
13036 inform (0, "%q+D declared here, later in the "
13037 "translation unit", fn);
13041 if (TREE_CODE (function) == IDENTIFIER_NODE)
13043 unqualified_name_lookup_error (function);
13044 release_tree_vector (call_args);
13045 return error_mark_node;
13049 /* Remember that there was a reference to this entity. */
13050 if (DECL_P (function))
13051 mark_used (function);
13053 if (TREE_CODE (function) == OFFSET_REF)
13054 ret = build_offset_ref_call_from_tree (function, &call_args);
13055 else if (TREE_CODE (function) == COMPONENT_REF)
13057 tree instance = TREE_OPERAND (function, 0);
13058 tree fn = TREE_OPERAND (function, 1);
13060 if (processing_template_decl
13061 && (type_dependent_expression_p (instance)
13062 || (!BASELINK_P (fn)
13063 && TREE_CODE (fn) != FIELD_DECL)
13064 || type_dependent_expression_p (fn)
13065 || any_type_dependent_arguments_p (call_args)))
13066 ret = build_nt_call_vec (function, call_args);
13067 else if (!BASELINK_P (fn))
13068 ret = finish_call_expr (function, &call_args,
13069 /*disallow_virtual=*/false,
13070 /*koenig_p=*/false,
13073 ret = (build_new_method_call
13075 &call_args, NULL_TREE,
13076 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13081 ret = finish_call_expr (function, &call_args,
13082 /*disallow_virtual=*/qualified_p,
13086 release_tree_vector (call_args);
13092 return build_x_conditional_expr
13093 (RECUR (TREE_OPERAND (t, 0)),
13094 RECUR (TREE_OPERAND (t, 1)),
13095 RECUR (TREE_OPERAND (t, 2)),
13098 case PSEUDO_DTOR_EXPR:
13099 return finish_pseudo_destructor_expr
13100 (RECUR (TREE_OPERAND (t, 0)),
13101 RECUR (TREE_OPERAND (t, 1)),
13102 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13106 tree purpose, value, chain;
13108 if (t == void_list_node)
13111 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13112 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13114 /* We have pack expansions, so expand those and
13115 create a new list out of it. */
13116 tree purposevec = NULL_TREE;
13117 tree valuevec = NULL_TREE;
13121 /* Expand the argument expressions. */
13122 if (TREE_PURPOSE (t))
13123 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13124 complain, in_decl);
13125 if (TREE_VALUE (t))
13126 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13127 complain, in_decl);
13129 /* Build the rest of the list. */
13130 chain = TREE_CHAIN (t);
13131 if (chain && chain != void_type_node)
13132 chain = RECUR (chain);
13134 /* Determine the number of arguments. */
13135 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13137 len = TREE_VEC_LENGTH (purposevec);
13138 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13140 else if (TREE_CODE (valuevec) == TREE_VEC)
13141 len = TREE_VEC_LENGTH (valuevec);
13144 /* Since we only performed a partial substitution into
13145 the argument pack, we only return a single list
13147 if (purposevec == TREE_PURPOSE (t)
13148 && valuevec == TREE_VALUE (t)
13149 && chain == TREE_CHAIN (t))
13152 return tree_cons (purposevec, valuevec, chain);
13155 /* Convert the argument vectors into a TREE_LIST */
13159 /* Grab the Ith values. */
13161 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13164 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13167 /* Build the list (backwards). */
13168 chain = tree_cons (purpose, value, chain);
13174 purpose = TREE_PURPOSE (t);
13176 purpose = RECUR (purpose);
13177 value = TREE_VALUE (t);
13179 value = RECUR (value);
13180 chain = TREE_CHAIN (t);
13181 if (chain && chain != void_type_node)
13182 chain = RECUR (chain);
13183 if (purpose == TREE_PURPOSE (t)
13184 && value == TREE_VALUE (t)
13185 && chain == TREE_CHAIN (t))
13187 return tree_cons (purpose, value, chain);
13190 case COMPONENT_REF:
13196 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13197 args, complain, in_decl);
13198 /* Remember that there was a reference to this entity. */
13199 if (DECL_P (object))
13200 mark_used (object);
13201 object_type = TREE_TYPE (object);
13203 member = TREE_OPERAND (t, 1);
13204 if (BASELINK_P (member))
13205 member = tsubst_baselink (member,
13206 non_reference (TREE_TYPE (object)),
13207 args, complain, in_decl);
13209 member = tsubst_copy (member, args, complain, in_decl);
13210 if (member == error_mark_node)
13211 return error_mark_node;
13213 if (object_type && !CLASS_TYPE_P (object_type))
13215 if (SCALAR_TYPE_P (object_type))
13217 tree s = NULL_TREE;
13218 tree dtor = member;
13220 if (TREE_CODE (dtor) == SCOPE_REF)
13222 s = TREE_OPERAND (dtor, 0);
13223 dtor = TREE_OPERAND (dtor, 1);
13225 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13227 dtor = TREE_OPERAND (dtor, 0);
13229 return finish_pseudo_destructor_expr (object, s, dtor);
13233 else if (TREE_CODE (member) == SCOPE_REF
13234 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13239 /* Lookup the template functions now that we know what the
13241 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13242 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13243 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13244 /*is_type_p=*/false,
13245 /*complain=*/false);
13246 if (BASELINK_P (member))
13248 BASELINK_FUNCTIONS (member)
13249 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13251 member = (adjust_result_of_qualified_name_lookup
13252 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13257 qualified_name_lookup_error (object_type, tmpl, member,
13259 return error_mark_node;
13262 else if (TREE_CODE (member) == SCOPE_REF
13263 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13264 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13266 if (complain & tf_error)
13268 if (TYPE_P (TREE_OPERAND (member, 0)))
13269 error ("%qT is not a class or namespace",
13270 TREE_OPERAND (member, 0));
13272 error ("%qD is not a class or namespace",
13273 TREE_OPERAND (member, 0));
13275 return error_mark_node;
13277 else if (TREE_CODE (member) == FIELD_DECL)
13278 return finish_non_static_data_member (member, object, NULL_TREE);
13280 return finish_class_member_access_expr (object, member,
13281 /*template_p=*/false,
13287 (RECUR (TREE_OPERAND (t, 0)));
13291 VEC(constructor_elt,gc) *n;
13292 constructor_elt *ce;
13293 unsigned HOST_WIDE_INT idx;
13294 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13295 bool process_index_p;
13297 bool need_copy_p = false;
13300 if (type == error_mark_node)
13301 return error_mark_node;
13303 /* digest_init will do the wrong thing if we let it. */
13304 if (type && TYPE_PTRMEMFUNC_P (type))
13307 /* We do not want to process the index of aggregate
13308 initializers as they are identifier nodes which will be
13309 looked up by digest_init. */
13310 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13312 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13313 newlen = VEC_length (constructor_elt, n);
13314 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13316 if (ce->index && process_index_p)
13317 ce->index = RECUR (ce->index);
13319 if (PACK_EXPANSION_P (ce->value))
13321 /* Substitute into the pack expansion. */
13322 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13325 if (ce->value == error_mark_node
13326 || PACK_EXPANSION_P (ce->value))
13328 else if (TREE_VEC_LENGTH (ce->value) == 1)
13329 /* Just move the argument into place. */
13330 ce->value = TREE_VEC_ELT (ce->value, 0);
13333 /* Update the length of the final CONSTRUCTOR
13334 arguments vector, and note that we will need to
13336 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13337 need_copy_p = true;
13341 ce->value = RECUR (ce->value);
13346 VEC(constructor_elt,gc) *old_n = n;
13348 n = VEC_alloc (constructor_elt, gc, newlen);
13349 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13351 if (TREE_CODE (ce->value) == TREE_VEC)
13353 int i, len = TREE_VEC_LENGTH (ce->value);
13354 for (i = 0; i < len; ++i)
13355 CONSTRUCTOR_APPEND_ELT (n, 0,
13356 TREE_VEC_ELT (ce->value, i));
13359 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13363 r = build_constructor (init_list_type_node, n);
13364 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13366 if (TREE_HAS_CONSTRUCTOR (t))
13367 return finish_compound_literal (type, r, complain);
13369 TREE_TYPE (r) = type;
13375 tree operand_0 = TREE_OPERAND (t, 0);
13376 if (TYPE_P (operand_0))
13378 operand_0 = tsubst (operand_0, args, complain, in_decl);
13379 return get_typeid (operand_0);
13383 operand_0 = RECUR (operand_0);
13384 return build_typeid (operand_0);
13395 tree r = tsubst_copy (t, args, complain, in_decl);
13397 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13398 /* If the original type was a reference, we'll be wrapped in
13399 the appropriate INDIRECT_REF. */
13400 r = convert_from_reference (r);
13405 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13406 tsubst (TREE_TYPE (t), args, complain, in_decl));
13408 case OFFSETOF_EXPR:
13409 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13413 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13414 complain, in_decl);
13416 tree type2 = TRAIT_EXPR_TYPE2 (t);
13418 type2 = tsubst_copy (type2, args, complain, in_decl);
13420 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13425 tree old_stmt_expr = cur_stmt_expr;
13426 tree stmt_expr = begin_stmt_expr ();
13428 cur_stmt_expr = stmt_expr;
13429 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13430 integral_constant_expression_p);
13431 stmt_expr = finish_stmt_expr (stmt_expr, false);
13432 cur_stmt_expr = old_stmt_expr;
13434 /* If the resulting list of expression statement is empty,
13435 fold it further into void_zero_node. */
13436 if (empty_expr_stmt_p (stmt_expr))
13437 stmt_expr = void_zero_node;
13443 t = tsubst_copy (t, args, complain, in_decl);
13444 /* As in finish_id_expression, we resolve enumeration constants
13445 to their underlying values. */
13446 if (TREE_CODE (t) == CONST_DECL)
13448 used_types_insert (TREE_TYPE (t));
13449 return DECL_INITIAL (t);
13455 tree r = build_lambda_expr ();
13457 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13458 TREE_TYPE (r) = type;
13459 CLASSTYPE_LAMBDA_EXPR (type) = r;
13461 LAMBDA_EXPR_LOCATION (r)
13462 = LAMBDA_EXPR_LOCATION (t);
13463 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13464 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13465 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13466 LAMBDA_EXPR_DISCRIMINATOR (r)
13467 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13468 LAMBDA_EXPR_CAPTURE_LIST (r)
13469 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13470 LAMBDA_EXPR_THIS_CAPTURE (r)
13471 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
13472 LAMBDA_EXPR_EXTRA_SCOPE (r)
13473 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13475 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13476 determine_visibility (TYPE_NAME (type));
13477 /* Now that we know visibility, instantiate the type so we have a
13478 declaration of the op() for later calls to lambda_function. */
13479 complete_type (type);
13481 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13483 apply_lambda_return_type (r, type);
13485 return build_lambda_object (r);
13489 /* We can get here for a constant initializer of non-dependent type.
13490 FIXME stop folding in cp_parser_initializer_clause. */
13491 gcc_assert (TREE_CONSTANT (t));
13493 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
13494 TREE_CONSTANT (r) = true;
13499 /* Handle Objective-C++ constructs, if appropriate. */
13502 = objcp_tsubst_copy_and_build (t, args, complain,
13503 in_decl, /*function_p=*/false);
13507 return tsubst_copy (t, args, complain, in_decl);
13513 /* Verify that the instantiated ARGS are valid. For type arguments,
13514 make sure that the type's linkage is ok. For non-type arguments,
13515 make sure they are constants if they are integral or enumerations.
13516 Emit an error under control of COMPLAIN, and return TRUE on error. */
13519 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13521 if (ARGUMENT_PACK_P (t))
13523 tree vec = ARGUMENT_PACK_ARGS (t);
13524 int len = TREE_VEC_LENGTH (vec);
13525 bool result = false;
13528 for (i = 0; i < len; ++i)
13529 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13533 else if (TYPE_P (t))
13535 /* [basic.link]: A name with no linkage (notably, the name
13536 of a class or enumeration declared in a local scope)
13537 shall not be used to declare an entity with linkage.
13538 This implies that names with no linkage cannot be used as
13541 DR 757 relaxes this restriction for C++0x. */
13542 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13543 : no_linkage_check (t, /*relaxed_p=*/false));
13547 /* DR 488 makes use of a type with no linkage cause
13548 type deduction to fail. */
13549 if (complain & tf_error)
13551 if (TYPE_ANONYMOUS_P (nt))
13552 error ("%qT is/uses anonymous type", t);
13554 error ("template argument for %qD uses local type %qT",
13559 /* In order to avoid all sorts of complications, we do not
13560 allow variably-modified types as template arguments. */
13561 else if (variably_modified_type_p (t, NULL_TREE))
13563 if (complain & tf_error)
13564 error ("%qT is a variably modified type", t);
13568 /* A non-type argument of integral or enumerated type must be a
13570 else if (TREE_TYPE (t)
13571 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13572 && !TREE_CONSTANT (t))
13574 if (complain & tf_error)
13575 error ("integral expression %qE is not constant", t);
13582 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13584 int ix, len = DECL_NTPARMS (tmpl);
13585 bool result = false;
13587 for (ix = 0; ix != len; ix++)
13589 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13592 if (result && (complain & tf_error))
13593 error (" trying to instantiate %qD", tmpl);
13597 DEF_VEC_O (spec_entry);
13598 DEF_VEC_ALLOC_O (spec_entry,gc);
13599 static GTY(()) VEC(spec_entry,gc) *current_deduction_vec;
13600 static GTY((param_is (spec_entry))) htab_t current_deduction_htab;
13602 /* In C++0x, it's possible to have a function template whose type depends
13603 on itself recursively. This is most obvious with decltype, but can also
13604 occur with enumeration scope (c++/48969). So we need to catch infinite
13605 recursion and reject the substitution at deduction time; this function
13606 will return error_mark_node for any repeated substitution.
13608 This also catches excessive recursion such as when f<N> depends on
13609 f<N-1> across all integers, and returns error_mark_node for all the
13610 substitutions back up to the initial one.
13612 This is, of course, not reentrant.
13614 Use of a VEC here is O(n^2) in the depth of function template argument
13615 deduction substitution, but using a hash table creates a lot of constant
13616 overhead for the typical case of very low depth. So to make the typical
13617 case fast we start out with a VEC and switch to a hash table only if
13618 depth gets to be significant; in one metaprogramming testcase, even at
13619 depth 80 the overhead of the VEC relative to a hash table was only about
13620 0.5% of compile time. */
13623 deduction_tsubst_fntype (tree fn, tree targs)
13625 static bool excessive_deduction_depth;
13634 tree fntype = TREE_TYPE (fn);
13636 /* We don't need to worry about this in C++98. */
13637 if (cxx_dialect < cxx0x)
13639 push_deduction_access_scope (fn);
13640 r = tsubst (fntype, targs, tf_none, NULL_TREE);
13641 pop_deduction_access_scope (fn);
13645 /* If we're seeing a lot of recursion, switch over to a hash table. The
13646 constant 40 is fairly arbitrary. */
13647 if (!current_deduction_htab
13648 && VEC_length (spec_entry, current_deduction_vec) > 40)
13650 current_deduction_htab = htab_create_ggc (40*2, hash_specialization,
13651 eq_specializations, ggc_free);
13652 FOR_EACH_VEC_ELT (spec_entry, current_deduction_vec, i, p)
13654 slot = (spec_entry **) htab_find_slot (current_deduction_htab,
13656 *slot = ggc_alloc_spec_entry ();
13659 VEC_free (spec_entry, gc, current_deduction_vec);
13662 /* Now check everything in the vector, if any. */
13663 FOR_EACH_VEC_ELT (spec_entry, current_deduction_vec, i, p)
13664 if (p->tmpl == fn && comp_template_args (p->args, targs))
13666 p->spec = error_mark_node;
13667 return error_mark_node;
13672 elt.spec = NULL_TREE;
13674 /* If we've created a hash table, look there. */
13675 if (current_deduction_htab)
13677 if (htab_elements (current_deduction_htab)
13678 > (unsigned) max_tinst_depth)
13680 /* Trying to recurse across all integers or some such. */
13681 excessive_deduction_depth = true;
13682 return error_mark_node;
13685 hash = hash_specialization (&elt);
13686 slot = (spec_entry **)
13687 htab_find_slot_with_hash (current_deduction_htab, &elt, hash, INSERT);
13690 /* We already have an entry for this. */
13691 (*slot)->spec = error_mark_node;
13692 return error_mark_node;
13696 /* Create a new entry. */
13697 *slot = ggc_alloc_spec_entry ();
13703 /* No hash table, so add it to the VEC. */
13705 VEC_safe_push (spec_entry, gc, current_deduction_vec, &elt);
13708 push_deduction_access_scope (fn);
13709 r = tsubst (fntype, targs, tf_none, NULL_TREE);
13710 pop_deduction_access_scope (fn);
13712 /* After doing the substitution, make sure we didn't hit it again. Note
13713 that we might have switched to a hash table during tsubst. */
13714 if (current_deduction_htab)
13717 hash = hash_specialization (&elt);
13718 slot = (spec_entry **)
13719 htab_find_slot_with_hash (current_deduction_htab, &elt, hash,
13721 if ((*slot)->spec == error_mark_node)
13722 r = error_mark_node;
13723 htab_clear_slot (current_deduction_htab, (void**)slot);
13727 if (VEC_last (spec_entry, current_deduction_vec)->spec
13728 == error_mark_node)
13729 r = error_mark_node;
13730 VEC_pop (spec_entry, current_deduction_vec);
13732 if (excessive_deduction_depth)
13734 r = error_mark_node;
13735 if (htab_elements (current_deduction_htab) == 0)
13736 /* Reset once we're all the way out. */
13737 excessive_deduction_depth = false;
13742 /* Instantiate the indicated variable or function template TMPL with
13743 the template arguments in TARG_PTR. */
13746 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
13748 tree targ_ptr = orig_args;
13752 HOST_WIDE_INT saved_processing_template_decl;
13754 if (tmpl == error_mark_node)
13755 return error_mark_node;
13757 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13759 /* If this function is a clone, handle it specially. */
13760 if (DECL_CLONED_FUNCTION_P (tmpl))
13765 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13766 DECL_CLONED_FUNCTION. */
13767 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13768 targ_ptr, complain);
13769 if (spec == error_mark_node)
13770 return error_mark_node;
13772 /* Look for the clone. */
13773 FOR_EACH_CLONE (clone, spec)
13774 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13776 /* We should always have found the clone by now. */
13777 gcc_unreachable ();
13781 /* Check to see if we already have this specialization. */
13782 gen_tmpl = most_general_template (tmpl);
13783 if (tmpl != gen_tmpl)
13784 /* The TMPL is a partial instantiation. To get a full set of
13785 arguments we must add the arguments used to perform the
13786 partial instantiation. */
13787 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13790 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13791 but it doesn't seem to be on the hot path. */
13792 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13794 gcc_assert (tmpl == gen_tmpl
13795 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13797 || fndecl == NULL_TREE);
13799 if (spec != NULL_TREE)
13802 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13804 return error_mark_node;
13806 /* We are building a FUNCTION_DECL, during which the access of its
13807 parameters and return types have to be checked. However this
13808 FUNCTION_DECL which is the desired context for access checking
13809 is not built yet. We solve this chicken-and-egg problem by
13810 deferring all checks until we have the FUNCTION_DECL. */
13811 push_deferring_access_checks (dk_deferred);
13813 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13814 (because, for example, we have encountered a non-dependent
13815 function call in the body of a template function and must now
13816 determine which of several overloaded functions will be called),
13817 within the instantiation itself we are not processing a
13819 saved_processing_template_decl = processing_template_decl;
13820 processing_template_decl = 0;
13821 /* Substitute template parameters to obtain the specialization. */
13822 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13823 targ_ptr, complain, gen_tmpl);
13824 processing_template_decl = saved_processing_template_decl;
13825 if (fndecl == error_mark_node)
13826 return error_mark_node;
13828 /* Now we know the specialization, compute access previously
13830 push_access_scope (fndecl);
13832 /* Some typedefs referenced from within the template code need to be access
13833 checked at template instantiation time, i.e now. These types were
13834 added to the template at parsing time. Let's get those and perfom
13835 the acces checks then. */
13836 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13837 perform_deferred_access_checks ();
13838 pop_access_scope (fndecl);
13839 pop_deferring_access_checks ();
13841 /* The DECL_TI_TEMPLATE should always be the immediate parent
13842 template, not the most general template. */
13843 DECL_TI_TEMPLATE (fndecl) = tmpl;
13845 /* If we've just instantiated the main entry point for a function,
13846 instantiate all the alternate entry points as well. We do this
13847 by cloning the instantiation of the main entry point, not by
13848 instantiating the template clones. */
13849 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13850 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13855 /* Wrapper for instantiate_template_1. */
13858 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13861 timevar_push (TV_TEMPLATE_INST);
13862 ret = instantiate_template_1 (tmpl, orig_args, complain);
13863 timevar_pop (TV_TEMPLATE_INST);
13867 /* We're going to do deduction substitution on the type of TMPL, a function
13868 template. In C++11 mode, push into that access scope. In C++03 mode,
13869 disable access checking. */
13872 push_deduction_access_scope (tree tmpl)
13874 if (cxx_dialect >= cxx0x)
13875 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13877 push_deferring_access_checks (dk_no_check);
13880 /* And pop back out. */
13883 pop_deduction_access_scope (tree tmpl)
13885 if (cxx_dialect >= cxx0x)
13886 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13888 pop_deferring_access_checks ();
13891 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13892 NARGS elements of the arguments that are being used when calling
13893 it. TARGS is a vector into which the deduced template arguments
13896 Return zero for success, 2 for an incomplete match that doesn't resolve
13897 all the types, and 1 for complete failure. An error message will be
13898 printed only for an incomplete match.
13900 If FN is a conversion operator, or we are trying to produce a specific
13901 specialization, RETURN_TYPE is the return type desired.
13903 The EXPLICIT_TARGS are explicit template arguments provided via a
13906 The parameter STRICT is one of:
13909 We are deducing arguments for a function call, as in
13910 [temp.deduct.call].
13913 We are deducing arguments for a conversion function, as in
13914 [temp.deduct.conv].
13917 We are deducing arguments when doing an explicit instantiation
13918 as in [temp.explicit], when determining an explicit specialization
13919 as in [temp.expl.spec], or when taking the address of a function
13920 template, as in [temp.deduct.funcaddr]. */
13923 fn_type_unification (tree fn,
13924 tree explicit_targs,
13927 unsigned int nargs,
13929 unification_kind_t strict,
13935 bool incomplete_argument_packs_p = false;
13937 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13939 fntype = TREE_TYPE (fn);
13940 if (explicit_targs)
13944 The specified template arguments must match the template
13945 parameters in kind (i.e., type, nontype, template), and there
13946 must not be more arguments than there are parameters;
13947 otherwise type deduction fails.
13949 Nontype arguments must match the types of the corresponding
13950 nontype template parameters, or must be convertible to the
13951 types of the corresponding nontype parameters as specified in
13952 _temp.arg.nontype_, otherwise type deduction fails.
13954 All references in the function type of the function template
13955 to the corresponding template parameters are replaced by the
13956 specified template argument values. If a substitution in a
13957 template parameter or in the function type of the function
13958 template results in an invalid type, type deduction fails. */
13959 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13960 int i, len = TREE_VEC_LENGTH (tparms);
13961 tree converted_args;
13962 bool incomplete = false;
13964 if (explicit_targs == error_mark_node)
13968 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13969 /*require_all_args=*/false,
13970 /*use_default_args=*/false));
13971 if (converted_args == error_mark_node)
13974 /* Substitute the explicit args into the function type. This is
13975 necessary so that, for instance, explicitly declared function
13976 arguments can match null pointed constants. If we were given
13977 an incomplete set of explicit args, we must not do semantic
13978 processing during substitution as we could create partial
13980 for (i = 0; i < len; i++)
13982 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13983 bool parameter_pack = false;
13985 /* Dig out the actual parm. */
13986 if (TREE_CODE (parm) == TYPE_DECL
13987 || TREE_CODE (parm) == TEMPLATE_DECL)
13989 parm = TREE_TYPE (parm);
13990 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13992 else if (TREE_CODE (parm) == PARM_DECL)
13994 parm = DECL_INITIAL (parm);
13995 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13998 if (parameter_pack)
14002 template_parm_level_and_index (parm, &level, &idx);
14004 /* Mark the argument pack as "incomplete". We could
14005 still deduce more arguments during unification.
14006 We remove this mark in type_unification_real. */
14007 targ = TMPL_ARG (converted_args, level, idx);
14010 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14011 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14012 = ARGUMENT_PACK_ARGS (targ);
14015 /* We have some incomplete argument packs. */
14016 incomplete_argument_packs_p = true;
14020 if (incomplete_argument_packs_p)
14021 /* Any substitution is guaranteed to be incomplete if there
14022 are incomplete argument packs, because we can still deduce
14026 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
14028 processing_template_decl += incomplete;
14029 fntype = deduction_tsubst_fntype (fn, converted_args);
14030 processing_template_decl -= incomplete;
14032 if (fntype == error_mark_node)
14035 /* Place the explicitly specified arguments in TARGS. */
14036 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14037 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14040 /* Never do unification on the 'this' parameter. */
14041 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14047 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14048 new_args = XALLOCAVEC (tree, nargs + 1);
14049 new_args[0] = return_type;
14050 memcpy (new_args + 1, args, nargs * sizeof (tree));
14055 /* We allow incomplete unification without an error message here
14056 because the standard doesn't seem to explicitly prohibit it. Our
14057 callers must be ready to deal with unification failures in any
14059 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14060 targs, parms, args, nargs, /*subr=*/0,
14063 /* Now that we have bindings for all of the template arguments,
14064 ensure that the arguments deduced for the template template
14065 parameters have compatible template parameter lists. We cannot
14066 check this property before we have deduced all template
14067 arguments, because the template parameter types of a template
14068 template parameter might depend on prior template parameters
14069 deduced after the template template parameter. The following
14070 ill-formed example illustrates this issue:
14072 template<typename T, template<T> class C> void f(C<5>, T);
14074 template<int N> struct X {};
14077 f(X<5>(), 5l); // error: template argument deduction fails
14080 The template parameter list of 'C' depends on the template type
14081 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14082 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14083 time that we deduce 'C'. */
14085 && !template_template_parm_bindings_ok_p
14086 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14090 /* All is well so far. Now, check:
14094 When all template arguments have been deduced, all uses of
14095 template parameters in nondeduced contexts are replaced with
14096 the corresponding deduced argument values. If the
14097 substitution results in an invalid type, as described above,
14098 type deduction fails. */
14100 tree substed = deduction_tsubst_fntype (fn, targs);
14101 if (substed == error_mark_node)
14104 /* If we're looking for an exact match, check that what we got
14105 is indeed an exact match. It might not be if some template
14106 parameters are used in non-deduced contexts. */
14107 if (strict == DEDUCE_EXACT)
14112 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14114 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14115 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14116 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14124 /* Adjust types before performing type deduction, as described in
14125 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14126 sections are symmetric. PARM is the type of a function parameter
14127 or the return type of the conversion function. ARG is the type of
14128 the argument passed to the call, or the type of the value
14129 initialized with the result of the conversion function.
14130 ARG_EXPR is the original argument expression, which may be null. */
14133 maybe_adjust_types_for_deduction (unification_kind_t strict,
14147 /* Swap PARM and ARG throughout the remainder of this
14148 function; the handling is precisely symmetric since PARM
14149 will initialize ARG rather than vice versa. */
14157 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14158 too, but here handle it by stripping the reference from PARM
14159 rather than by adding it to ARG. */
14160 if (TREE_CODE (*parm) == REFERENCE_TYPE
14161 && TYPE_REF_IS_RVALUE (*parm)
14162 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14163 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14164 && TREE_CODE (*arg) == REFERENCE_TYPE
14165 && !TYPE_REF_IS_RVALUE (*arg))
14166 *parm = TREE_TYPE (*parm);
14167 /* Nothing else to do in this case. */
14171 gcc_unreachable ();
14174 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14176 /* [temp.deduct.call]
14178 If P is not a reference type:
14180 --If A is an array type, the pointer type produced by the
14181 array-to-pointer standard conversion (_conv.array_) is
14182 used in place of A for type deduction; otherwise,
14184 --If A is a function type, the pointer type produced by
14185 the function-to-pointer standard conversion
14186 (_conv.func_) is used in place of A for type deduction;
14189 --If A is a cv-qualified type, the top level
14190 cv-qualifiers of A's type are ignored for type
14192 if (TREE_CODE (*arg) == ARRAY_TYPE)
14193 *arg = build_pointer_type (TREE_TYPE (*arg));
14194 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14195 *arg = build_pointer_type (*arg);
14197 *arg = TYPE_MAIN_VARIANT (*arg);
14200 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14201 of the form T&&, where T is a template parameter, and the argument
14202 is an lvalue, T is deduced as A& */
14203 if (TREE_CODE (*parm) == REFERENCE_TYPE
14204 && TYPE_REF_IS_RVALUE (*parm)
14205 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14206 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14207 && (arg_expr ? real_lvalue_p (arg_expr)
14208 /* try_one_overload doesn't provide an arg_expr, but
14209 functions are always lvalues. */
14210 : TREE_CODE (*arg) == FUNCTION_TYPE))
14211 *arg = build_reference_type (*arg);
14213 /* [temp.deduct.call]
14215 If P is a cv-qualified type, the top level cv-qualifiers
14216 of P's type are ignored for type deduction. If P is a
14217 reference type, the type referred to by P is used for
14219 *parm = TYPE_MAIN_VARIANT (*parm);
14220 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14222 *parm = TREE_TYPE (*parm);
14223 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14226 /* DR 322. For conversion deduction, remove a reference type on parm
14227 too (which has been swapped into ARG). */
14228 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14229 *arg = TREE_TYPE (*arg);
14234 /* Most parms like fn_type_unification.
14236 If SUBR is 1, we're being called recursively (to unify the
14237 arguments of a function or method parameter of a function
14241 type_unification_real (tree tparms,
14245 unsigned int xnargs,
14247 unification_kind_t strict,
14250 tree parm, arg, arg_expr;
14252 int ntparms = TREE_VEC_LENGTH (tparms);
14254 int saw_undeduced = 0;
14257 unsigned int nargs;
14260 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14261 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14262 gcc_assert (ntparms > 0);
14264 /* Reset the number of non-defaulted template arguments contained
14266 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14271 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
14272 | UNIFY_ALLOW_DERIVED);
14276 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14280 sub_strict = UNIFY_ALLOW_NONE;
14284 gcc_unreachable ();
14293 while (parms && parms != void_list_node
14296 parm = TREE_VALUE (parms);
14298 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
14299 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
14300 /* For a function parameter pack that occurs at the end of the
14301 parameter-declaration-list, the type A of each remaining
14302 argument of the call is compared with the type P of the
14303 declarator-id of the function parameter pack. */
14306 parms = TREE_CHAIN (parms);
14308 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
14309 /* For a function parameter pack that does not occur at the
14310 end of the parameter-declaration-list, the type of the
14311 parameter pack is a non-deduced context. */
14318 if (arg == error_mark_node)
14320 if (arg == unknown_type_node)
14321 /* We can't deduce anything from this, but we might get all the
14322 template args from other function args. */
14325 /* Conversions will be performed on a function argument that
14326 corresponds with a function parameter that contains only
14327 non-deducible template parameters and explicitly specified
14328 template parameters. */
14329 if (!uses_template_parms (parm))
14334 type = TREE_TYPE (arg);
14338 if (same_type_p (parm, type))
14340 if (strict != DEDUCE_EXACT
14341 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
14350 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14351 if (type_unknown_p (arg))
14353 /* [temp.deduct.type]
14355 A template-argument can be deduced from a pointer to
14356 function or pointer to member function argument if
14357 the set of overloaded functions does not contain
14358 function templates and at most one of a set of
14359 overloaded functions provides a unique match. */
14360 if (resolve_overloaded_unification
14361 (tparms, targs, parm, arg, strict, sub_strict))
14367 arg = unlowered_expr_type (arg);
14368 if (arg == error_mark_node)
14373 int arg_strict = sub_strict;
14376 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14379 if (arg == init_list_type_node && arg_expr)
14381 if (unify (tparms, targs, parm, arg, arg_strict))
14388 && parms != void_list_node
14389 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14391 /* Unify the remaining arguments with the pack expansion type. */
14393 tree parmvec = make_tree_vec (1);
14395 /* Allocate a TREE_VEC and copy in all of the arguments */
14396 argvec = make_tree_vec (nargs - ia);
14397 for (i = 0; ia < nargs; ++ia, ++i)
14398 TREE_VEC_ELT (argvec, i) = args[ia];
14400 /* Copy the parameter into parmvec. */
14401 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14402 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14403 /*call_args_p=*/true, /*subr=*/subr))
14406 /* Advance to the end of the list of parameters. */
14407 parms = TREE_CHAIN (parms);
14410 /* Fail if we've reached the end of the parm list, and more args
14411 are present, and the parm list isn't variadic. */
14412 if (ia < nargs && parms == void_list_node)
14414 /* Fail if parms are left and they don't have default values. */
14415 if (parms && parms != void_list_node
14416 && TREE_PURPOSE (parms) == NULL_TREE)
14421 /* Check to see if we need another pass before we start clearing
14422 ARGUMENT_PACK_INCOMPLETE_P. */
14423 for (i = 0; i < ntparms; i++)
14425 tree targ = TREE_VEC_ELT (targs, i);
14426 tree tparm = TREE_VEC_ELT (tparms, i);
14428 if (targ || tparm == error_mark_node)
14430 tparm = TREE_VALUE (tparm);
14432 /* If this is an undeduced nontype parameter that depends on
14433 a type parameter, try another pass; its type may have been
14434 deduced from a later argument than the one from which
14435 this parameter can be deduced. */
14436 if (TREE_CODE (tparm) == PARM_DECL
14437 && uses_template_parms (TREE_TYPE (tparm))
14438 && !saw_undeduced++)
14442 for (i = 0; i < ntparms; i++)
14444 tree targ = TREE_VEC_ELT (targs, i);
14445 tree tparm = TREE_VEC_ELT (tparms, i);
14447 /* Clear the "incomplete" flags on all argument packs now so that
14448 substituting them into later default arguments works. */
14449 if (targ && ARGUMENT_PACK_P (targ))
14451 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14452 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14455 if (targ || tparm == error_mark_node)
14457 tparm = TREE_VALUE (tparm);
14459 /* Core issue #226 (C++0x) [temp.deduct]:
14461 If a template argument has not been deduced, its
14462 default template argument, if any, is used.
14464 When we are in C++98 mode, TREE_PURPOSE will either
14465 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14466 to explicitly check cxx_dialect here. */
14467 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14469 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14470 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14471 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14472 arg = convert_template_argument (parm, arg, targs, tf_none,
14474 if (arg == error_mark_node)
14478 TREE_VEC_ELT (targs, i) = arg;
14479 /* The position of the first default template argument,
14480 is also the number of non-defaulted arguments in TARGS.
14482 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14483 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14488 /* If the type parameter is a parameter pack, then it will
14489 be deduced to an empty parameter pack. */
14490 if (template_parameter_pack_p (tparm))
14494 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14496 arg = make_node (NONTYPE_ARGUMENT_PACK);
14497 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14498 TREE_CONSTANT (arg) = 1;
14501 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14503 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14505 TREE_VEC_ELT (targs, i) = arg;
14512 #ifdef ENABLE_CHECKING
14513 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14514 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14520 /* Subroutine of type_unification_real. Args are like the variables
14521 at the call site. ARG is an overloaded function (or template-id);
14522 we try deducing template args from each of the overloads, and if
14523 only one succeeds, we go with that. Modifies TARGS and returns
14524 true on success. */
14527 resolve_overloaded_unification (tree tparms,
14531 unification_kind_t strict,
14534 tree tempargs = copy_node (targs);
14536 tree goodfn = NULL_TREE;
14539 if (TREE_CODE (arg) == ADDR_EXPR)
14541 arg = TREE_OPERAND (arg, 0);
14547 if (TREE_CODE (arg) == COMPONENT_REF)
14548 /* Handle `&x' where `x' is some static or non-static member
14550 arg = TREE_OPERAND (arg, 1);
14552 if (TREE_CODE (arg) == OFFSET_REF)
14553 arg = TREE_OPERAND (arg, 1);
14555 /* Strip baselink information. */
14556 if (BASELINK_P (arg))
14557 arg = BASELINK_FUNCTIONS (arg);
14559 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14561 /* If we got some explicit template args, we need to plug them into
14562 the affected templates before we try to unify, in case the
14563 explicit args will completely resolve the templates in question. */
14565 tree expl_subargs = TREE_OPERAND (arg, 1);
14566 arg = TREE_OPERAND (arg, 0);
14568 for (; arg; arg = OVL_NEXT (arg))
14570 tree fn = OVL_CURRENT (arg);
14571 tree subargs, elem;
14573 if (TREE_CODE (fn) != TEMPLATE_DECL)
14576 ++processing_template_decl;
14577 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14578 expl_subargs, /*check_ret=*/false);
14581 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14582 if (try_one_overload (tparms, targs, tempargs, parm,
14583 elem, strict, sub_strict, addr_p)
14584 && (!goodfn || !decls_match (goodfn, elem)))
14590 --processing_template_decl;
14593 else if (TREE_CODE (arg) != OVERLOAD
14594 && TREE_CODE (arg) != FUNCTION_DECL)
14595 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14596 -- but the deduction does not succeed because the expression is
14597 not just the function on its own. */
14600 for (; arg; arg = OVL_NEXT (arg))
14601 if (try_one_overload (tparms, targs, tempargs, parm,
14602 TREE_TYPE (OVL_CURRENT (arg)),
14603 strict, sub_strict, addr_p)
14604 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
14606 goodfn = OVL_CURRENT (arg);
14610 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14611 to function or pointer to member function argument if the set of
14612 overloaded functions does not contain function templates and at most
14613 one of a set of overloaded functions provides a unique match.
14615 So if we found multiple possibilities, we return success but don't
14616 deduce anything. */
14620 int i = TREE_VEC_LENGTH (targs);
14622 if (TREE_VEC_ELT (tempargs, i))
14623 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
14631 /* Core DR 115: In contexts where deduction is done and fails, or in
14632 contexts where deduction is not done, if a template argument list is
14633 specified and it, along with any default template arguments, identifies
14634 a single function template specialization, then the template-id is an
14635 lvalue for the function template specialization. */
14638 resolve_nondeduced_context (tree orig_expr)
14640 tree expr, offset, baselink;
14643 if (!type_unknown_p (orig_expr))
14648 offset = NULL_TREE;
14649 baselink = NULL_TREE;
14651 if (TREE_CODE (expr) == ADDR_EXPR)
14653 expr = TREE_OPERAND (expr, 0);
14656 if (TREE_CODE (expr) == OFFSET_REF)
14659 expr = TREE_OPERAND (expr, 1);
14661 if (TREE_CODE (expr) == BASELINK)
14664 expr = BASELINK_FUNCTIONS (expr);
14667 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
14670 tree goodfn = NULL_TREE;
14672 /* If we got some explicit template args, we need to plug them into
14673 the affected templates before we try to unify, in case the
14674 explicit args will completely resolve the templates in question. */
14676 tree expl_subargs = TREE_OPERAND (expr, 1);
14677 tree arg = TREE_OPERAND (expr, 0);
14678 tree badfn = NULL_TREE;
14679 tree badargs = NULL_TREE;
14681 for (; arg; arg = OVL_NEXT (arg))
14683 tree fn = OVL_CURRENT (arg);
14684 tree subargs, elem;
14686 if (TREE_CODE (fn) != TEMPLATE_DECL)
14689 ++processing_template_decl;
14690 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14691 expl_subargs, /*check_ret=*/false);
14692 if (subargs && !any_dependent_template_arguments_p (subargs))
14694 elem = instantiate_template (fn, subargs, tf_none);
14695 if (elem == error_mark_node)
14700 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
14706 --processing_template_decl;
14712 expr = build_baselink (BASELINK_BINFO (baselink),
14713 BASELINK_ACCESS_BINFO (baselink),
14714 expr, BASELINK_OPTYPE (baselink));
14718 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
14719 expr = build_offset_ref (base, expr, addr);
14722 expr = cp_build_addr_expr (expr, tf_warning_or_error);
14725 else if (good == 0 && badargs)
14726 /* There were no good options and at least one bad one, so let the
14727 user know what the problem is. */
14728 instantiate_template (badfn, badargs, tf_warning_or_error);
14733 /* Subroutine of resolve_overloaded_unification; does deduction for a single
14734 overload. Fills TARGS with any deduced arguments, or error_mark_node if
14735 different overloads deduce different arguments for a given parm.
14736 ADDR_P is true if the expression for which deduction is being
14737 performed was of the form "& fn" rather than simply "fn".
14739 Returns 1 on success. */
14742 try_one_overload (tree tparms,
14747 unification_kind_t strict,
14755 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14756 to function or pointer to member function argument if the set of
14757 overloaded functions does not contain function templates and at most
14758 one of a set of overloaded functions provides a unique match.
14760 So if this is a template, just return success. */
14762 if (uses_template_parms (arg))
14765 if (TREE_CODE (arg) == METHOD_TYPE)
14766 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14768 arg = build_pointer_type (arg);
14770 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14772 /* We don't copy orig_targs for this because if we have already deduced
14773 some template args from previous args, unify would complain when we
14774 try to deduce a template parameter for the same argument, even though
14775 there isn't really a conflict. */
14776 nargs = TREE_VEC_LENGTH (targs);
14777 tempargs = make_tree_vec (nargs);
14779 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14782 /* First make sure we didn't deduce anything that conflicts with
14783 explicitly specified args. */
14784 for (i = nargs; i--; )
14786 tree elt = TREE_VEC_ELT (tempargs, i);
14787 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14791 else if (uses_template_parms (elt))
14792 /* Since we're unifying against ourselves, we will fill in
14793 template args used in the function parm list with our own
14794 template parms. Discard them. */
14795 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14796 else if (oldelt && !template_args_equal (oldelt, elt))
14800 for (i = nargs; i--; )
14802 tree elt = TREE_VEC_ELT (tempargs, i);
14805 TREE_VEC_ELT (targs, i) = elt;
14811 /* PARM is a template class (perhaps with unbound template
14812 parameters). ARG is a fully instantiated type. If ARG can be
14813 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14814 TARGS are as for unify. */
14817 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14819 tree copy_of_targs;
14821 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14822 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14823 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14826 /* We need to make a new template argument vector for the call to
14827 unify. If we used TARGS, we'd clutter it up with the result of
14828 the attempted unification, even if this class didn't work out.
14829 We also don't want to commit ourselves to all the unifications
14830 we've already done, since unification is supposed to be done on
14831 an argument-by-argument basis. In other words, consider the
14832 following pathological case:
14834 template <int I, int J, int K>
14837 template <int I, int J>
14838 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14840 template <int I, int J, int K>
14841 void f(S<I, J, K>, S<I, I, I>);
14850 Now, by the time we consider the unification involving `s2', we
14851 already know that we must have `f<0, 0, 0>'. But, even though
14852 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14853 because there are two ways to unify base classes of S<0, 1, 2>
14854 with S<I, I, I>. If we kept the already deduced knowledge, we
14855 would reject the possibility I=1. */
14856 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14858 /* If unification failed, we're done. */
14859 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14860 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14866 /* Given a template type PARM and a class type ARG, find the unique
14867 base type in ARG that is an instance of PARM. We do not examine
14868 ARG itself; only its base-classes. If there is not exactly one
14869 appropriate base class, return NULL_TREE. PARM may be the type of
14870 a partial specialization, as well as a plain template type. Used
14874 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14876 tree rval = NULL_TREE;
14879 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14881 binfo = TYPE_BINFO (complete_type (arg));
14883 /* The type could not be completed. */
14886 /* Walk in inheritance graph order. The search order is not
14887 important, and this avoids multiple walks of virtual bases. */
14888 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14890 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14894 /* If there is more than one satisfactory baseclass, then:
14898 If they yield more than one possible deduced A, the type
14902 if (rval && !same_type_p (r, rval))
14912 /* Returns the level of DECL, which declares a template parameter. */
14915 template_decl_level (tree decl)
14917 switch (TREE_CODE (decl))
14920 case TEMPLATE_DECL:
14921 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14924 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14927 gcc_unreachable ();
14932 /* Decide whether ARG can be unified with PARM, considering only the
14933 cv-qualifiers of each type, given STRICT as documented for unify.
14934 Returns nonzero iff the unification is OK on that basis. */
14937 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14939 int arg_quals = cp_type_quals (arg);
14940 int parm_quals = cp_type_quals (parm);
14942 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14943 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14945 /* Although a CVR qualifier is ignored when being applied to a
14946 substituted template parameter ([8.3.2]/1 for example), that
14947 does not allow us to unify "const T" with "int&" because both
14948 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14949 It is ok when we're allowing additional CV qualifiers
14950 at the outer level [14.8.2.1]/3,1st bullet. */
14951 if ((TREE_CODE (arg) == REFERENCE_TYPE
14952 || TREE_CODE (arg) == FUNCTION_TYPE
14953 || TREE_CODE (arg) == METHOD_TYPE)
14954 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14957 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14958 && (parm_quals & TYPE_QUAL_RESTRICT))
14962 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14963 && (arg_quals & parm_quals) != parm_quals)
14966 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14967 && (parm_quals & arg_quals) != arg_quals)
14973 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14975 template_parm_level_and_index (tree parm, int* level, int* index)
14977 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14978 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14979 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14981 *index = TEMPLATE_TYPE_IDX (parm);
14982 *level = TEMPLATE_TYPE_LEVEL (parm);
14986 *index = TEMPLATE_PARM_IDX (parm);
14987 *level = TEMPLATE_PARM_LEVEL (parm);
14991 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14992 expansion at the end of PACKED_PARMS. Returns 0 if the type
14993 deduction succeeds, 1 otherwise. STRICT is the same as in
14994 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14995 call argument list. We'll need to adjust the arguments to make them
14996 types. SUBR tells us if this is from a recursive call to
14997 type_unification_real. */
14999 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15000 tree packed_args, int strict, bool call_args_p,
15004 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15005 tree pattern = PACK_EXPANSION_PATTERN (parm);
15006 tree pack, packs = NULL_TREE;
15007 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15008 int len = TREE_VEC_LENGTH (packed_args);
15010 /* Determine the parameter packs we will be deducing from the
15011 pattern, and record their current deductions. */
15012 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15013 pack; pack = TREE_CHAIN (pack))
15015 tree parm_pack = TREE_VALUE (pack);
15018 /* Determine the index and level of this parameter pack. */
15019 template_parm_level_and_index (parm_pack, &level, &idx);
15021 /* Keep track of the parameter packs and their corresponding
15023 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15024 TREE_TYPE (packs) = make_tree_vec (len - start);
15027 /* Loop through all of the arguments that have not yet been
15028 unified and unify each with the pattern. */
15029 for (i = start; i < len; i++)
15031 tree parm = pattern;
15033 /* For each parameter pack, clear out the deduced value so that
15034 we can deduce it again. */
15035 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15038 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15040 TMPL_ARG (targs, level, idx) = NULL_TREE;
15043 /* Unify the pattern with the current argument. */
15045 tree arg = TREE_VEC_ELT (packed_args, i);
15046 tree arg_expr = NULL_TREE;
15047 int arg_strict = strict;
15048 bool skip_arg_p = false;
15054 /* This mirrors what we do in type_unification_real. */
15058 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
15059 | UNIFY_ALLOW_MORE_CV_QUAL
15060 | UNIFY_ALLOW_DERIVED);
15064 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15068 sub_strict = UNIFY_ALLOW_NONE;
15072 gcc_unreachable ();
15077 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15078 if (type_unknown_p (arg))
15080 /* [temp.deduct.type] A template-argument can be
15081 deduced from a pointer to function or pointer
15082 to member function argument if the set of
15083 overloaded functions does not contain function
15084 templates and at most one of a set of
15085 overloaded functions provides a unique
15088 if (resolve_overloaded_unification
15089 (tparms, targs, parm, arg,
15090 (unification_kind_t) strict,
15100 arg = unlowered_expr_type (arg);
15101 if (arg == error_mark_node)
15106 arg_strict = sub_strict;
15110 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
15111 &parm, &arg, arg_expr);
15116 /* For deduction from an init-list we need the actual list. */
15117 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15119 if (unify (tparms, targs, parm, arg, arg_strict))
15124 /* For each parameter pack, collect the deduced value. */
15125 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15128 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15130 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15131 TMPL_ARG (targs, level, idx);
15135 /* Verify that the results of unification with the parameter packs
15136 produce results consistent with what we've seen before, and make
15137 the deduced argument packs available. */
15138 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15140 tree old_pack = TREE_VALUE (pack);
15141 tree new_args = TREE_TYPE (pack);
15142 int i, len = TREE_VEC_LENGTH (new_args);
15144 bool nondeduced_p = false;
15146 /* By default keep the original deduced argument pack.
15147 If necessary, more specific code is going to update the
15148 resulting deduced argument later down in this function. */
15149 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15150 TMPL_ARG (targs, level, idx) = old_pack;
15152 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15153 actually deduce anything. */
15154 for (i = 0; i < len && !nondeduced_p; ++i)
15155 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15156 nondeduced_p = true;
15160 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15162 /* Prepend the explicit arguments onto NEW_ARGS. */
15163 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15164 tree old_args = new_args;
15165 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
15166 int len = explicit_len + TREE_VEC_LENGTH (old_args);
15168 /* Copy the explicit arguments. */
15169 new_args = make_tree_vec (len);
15170 for (i = 0; i < explicit_len; i++)
15171 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
15173 /* Copy the deduced arguments. */
15174 for (; i < len; i++)
15175 TREE_VEC_ELT (new_args, i) =
15176 TREE_VEC_ELT (old_args, i - explicit_len);
15182 /* Build the deduced *_ARGUMENT_PACK. */
15183 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15185 result = make_node (NONTYPE_ARGUMENT_PACK);
15186 TREE_TYPE (result) =
15187 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15188 TREE_CONSTANT (result) = 1;
15191 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15193 SET_ARGUMENT_PACK_ARGS (result, new_args);
15195 /* Note the deduced argument packs for this parameter
15197 TMPL_ARG (targs, level, idx) = result;
15199 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15200 && (ARGUMENT_PACK_ARGS (old_pack)
15201 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15203 /* We only had the explicitly-provided arguments before, but
15204 now we have a complete set of arguments. */
15205 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15207 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15208 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15209 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15211 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
15213 /* Inconsistent unification of this parameter pack. */
15220 /* Deduce the value of template parameters. TPARMS is the (innermost)
15221 set of template parameters to a template. TARGS is the bindings
15222 for those template parameters, as determined thus far; TARGS may
15223 include template arguments for outer levels of template parameters
15224 as well. PARM is a parameter to a template function, or a
15225 subcomponent of that parameter; ARG is the corresponding argument.
15226 This function attempts to match PARM with ARG in a manner
15227 consistent with the existing assignments in TARGS. If more values
15228 are deduced, then TARGS is updated.
15230 Returns 0 if the type deduction succeeds, 1 otherwise. The
15231 parameter STRICT is a bitwise or of the following flags:
15234 Require an exact match between PARM and ARG.
15235 UNIFY_ALLOW_MORE_CV_QUAL:
15236 Allow the deduced ARG to be more cv-qualified (by qualification
15237 conversion) than ARG.
15238 UNIFY_ALLOW_LESS_CV_QUAL:
15239 Allow the deduced ARG to be less cv-qualified than ARG.
15240 UNIFY_ALLOW_DERIVED:
15241 Allow the deduced ARG to be a template base class of ARG,
15242 or a pointer to a template base class of the type pointed to by
15244 UNIFY_ALLOW_INTEGER:
15245 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15246 case for more information.
15247 UNIFY_ALLOW_OUTER_LEVEL:
15248 This is the outermost level of a deduction. Used to determine validity
15249 of qualification conversions. A valid qualification conversion must
15250 have const qualified pointers leading up to the inner type which
15251 requires additional CV quals, except at the outer level, where const
15252 is not required [conv.qual]. It would be normal to set this flag in
15253 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15254 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15255 This is the outermost level of a deduction, and PARM can be more CV
15256 qualified at this point.
15257 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15258 This is the outermost level of a deduction, and PARM can be less CV
15259 qualified at this point. */
15262 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
15267 int strict_in = strict;
15269 /* I don't think this will do the right thing with respect to types.
15270 But the only case I've seen it in so far has been array bounds, where
15271 signedness is the only information lost, and I think that will be
15273 while (TREE_CODE (parm) == NOP_EXPR)
15274 parm = TREE_OPERAND (parm, 0);
15276 if (arg == error_mark_node)
15278 if (arg == unknown_type_node
15279 || arg == init_list_type_node)
15280 /* We can't deduce anything from this, but we might get all the
15281 template args from other function args. */
15284 /* If PARM uses template parameters, then we can't bail out here,
15285 even if ARG == PARM, since we won't record unifications for the
15286 template parameters. We might need them if we're trying to
15287 figure out which of two things is more specialized. */
15288 if (arg == parm && !uses_template_parms (parm))
15291 /* Handle init lists early, so the rest of the function can assume
15292 we're dealing with a type. */
15293 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15297 tree orig_parm = parm;
15299 /* Replace T with std::initializer_list<T> for deduction. */
15300 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15301 && flag_deduce_init_list)
15302 parm = listify (parm);
15304 if (!is_std_init_list (parm))
15305 /* We can only deduce from an initializer list argument if the
15306 parameter is std::initializer_list; otherwise this is a
15307 non-deduced context. */
15310 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15312 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15314 int elt_strict = strict;
15316 if (elt == error_mark_node)
15319 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15321 tree type = TREE_TYPE (elt);
15322 /* It should only be possible to get here for a call. */
15323 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15324 elt_strict |= maybe_adjust_types_for_deduction
15325 (DEDUCE_CALL, &elttype, &type, elt);
15329 if (unify (tparms, targs, elttype, elt, elt_strict))
15333 /* If the std::initializer_list<T> deduction worked, replace the
15334 deduced A with std::initializer_list<A>. */
15335 if (orig_parm != parm)
15337 idx = TEMPLATE_TYPE_IDX (orig_parm);
15338 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15339 targ = listify (targ);
15340 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15345 /* Immediately reject some pairs that won't unify because of
15346 cv-qualification mismatches. */
15347 if (TREE_CODE (arg) == TREE_CODE (parm)
15349 /* It is the elements of the array which hold the cv quals of an array
15350 type, and the elements might be template type parms. We'll check
15351 when we recurse. */
15352 && TREE_CODE (arg) != ARRAY_TYPE
15353 /* We check the cv-qualifiers when unifying with template type
15354 parameters below. We want to allow ARG `const T' to unify with
15355 PARM `T' for example, when computing which of two templates
15356 is more specialized, for example. */
15357 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15358 && !check_cv_quals_for_unify (strict_in, arg, parm))
15361 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15362 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15363 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15364 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15365 strict &= ~UNIFY_ALLOW_DERIVED;
15366 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15367 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15369 switch (TREE_CODE (parm))
15371 case TYPENAME_TYPE:
15373 case UNBOUND_CLASS_TEMPLATE:
15374 /* In a type which contains a nested-name-specifier, template
15375 argument values cannot be deduced for template parameters used
15376 within the nested-name-specifier. */
15379 case TEMPLATE_TYPE_PARM:
15380 case TEMPLATE_TEMPLATE_PARM:
15381 case BOUND_TEMPLATE_TEMPLATE_PARM:
15382 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15383 if (tparm == error_mark_node)
15386 if (TEMPLATE_TYPE_LEVEL (parm)
15387 != template_decl_level (tparm))
15388 /* The PARM is not one we're trying to unify. Just check
15389 to see if it matches ARG. */
15390 return (TREE_CODE (arg) == TREE_CODE (parm)
15391 && same_type_p (parm, arg)) ? 0 : 1;
15392 idx = TEMPLATE_TYPE_IDX (parm);
15393 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15394 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15396 /* Check for mixed types and values. */
15397 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15398 && TREE_CODE (tparm) != TYPE_DECL)
15399 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15400 && TREE_CODE (tparm) != TEMPLATE_DECL))
15403 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15405 /* ARG must be constructed from a template class or a template
15406 template parameter. */
15407 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15408 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15412 tree parmvec = TYPE_TI_ARGS (parm);
15413 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15414 tree full_argvec = add_to_template_args (targs, argvec);
15416 = DECL_INNERMOST_TEMPLATE_PARMS
15417 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15419 int parm_variadic_p = 0;
15421 /* The resolution to DR150 makes clear that default
15422 arguments for an N-argument may not be used to bind T
15423 to a template template parameter with fewer than N
15424 parameters. It is not safe to permit the binding of
15425 default arguments as an extension, as that may change
15426 the meaning of a conforming program. Consider:
15428 struct Dense { static const unsigned int dim = 1; };
15430 template <template <typename> class View,
15432 void operator+(float, View<Block> const&);
15434 template <typename Block,
15435 unsigned int Dim = Block::dim>
15436 struct Lvalue_proxy { operator float() const; };
15440 Lvalue_proxy<Dense> p;
15445 Here, if Lvalue_proxy is permitted to bind to View, then
15446 the global operator+ will be used; if they are not, the
15447 Lvalue_proxy will be converted to float. */
15448 if (coerce_template_parms (parm_parms,
15450 TYPE_TI_TEMPLATE (parm),
15452 /*require_all_args=*/true,
15453 /*use_default_args=*/false)
15454 == error_mark_node)
15457 /* Deduce arguments T, i from TT<T> or TT<i>.
15458 We check each element of PARMVEC and ARGVEC individually
15459 rather than the whole TREE_VEC since they can have
15460 different number of elements. */
15462 parmvec = expand_template_argument_pack (parmvec);
15463 argvec = expand_template_argument_pack (argvec);
15465 len = TREE_VEC_LENGTH (parmvec);
15467 /* Check if the parameters end in a pack, making them
15470 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15471 parm_variadic_p = 1;
15473 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15476 for (i = 0; i < len - parm_variadic_p; ++i)
15478 if (unify (tparms, targs,
15479 TREE_VEC_ELT (parmvec, i),
15480 TREE_VEC_ELT (argvec, i),
15485 if (parm_variadic_p
15486 && unify_pack_expansion (tparms, targs,
15489 /*call_args_p=*/false,
15493 arg = TYPE_TI_TEMPLATE (arg);
15495 /* Fall through to deduce template name. */
15498 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15499 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15501 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15503 /* Simple cases: Value already set, does match or doesn't. */
15504 if (targ != NULL_TREE && template_args_equal (targ, arg))
15511 /* If PARM is `const T' and ARG is only `int', we don't have
15512 a match unless we are allowing additional qualification.
15513 If ARG is `const int' and PARM is just `T' that's OK;
15514 that binds `const int' to `T'. */
15515 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15519 /* Consider the case where ARG is `const volatile int' and
15520 PARM is `const T'. Then, T should be `volatile int'. */
15521 arg = cp_build_qualified_type_real
15522 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15523 if (arg == error_mark_node)
15526 /* Simple cases: Value already set, does match or doesn't. */
15527 if (targ != NULL_TREE && same_type_p (targ, arg))
15532 /* Make sure that ARG is not a variable-sized array. (Note
15533 that were talking about variable-sized arrays (like
15534 `int[n]'), rather than arrays of unknown size (like
15535 `int[]').) We'll get very confused by such a type since
15536 the bound of the array will not be computable in an
15537 instantiation. Besides, such types are not allowed in
15538 ISO C++, so we can do as we please here. */
15539 if (variably_modified_type_p (arg, NULL_TREE))
15542 /* Strip typedefs as in convert_template_argument. */
15543 arg = strip_typedefs (arg);
15546 /* If ARG is a parameter pack or an expansion, we cannot unify
15547 against it unless PARM is also a parameter pack. */
15548 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15549 && !template_parameter_pack_p (parm))
15552 /* If the argument deduction results is a METHOD_TYPE,
15553 then there is a problem.
15554 METHOD_TYPE doesn't map to any real C++ type the result of
15555 the deduction can not be of that type. */
15556 if (TREE_CODE (arg) == METHOD_TYPE)
15559 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15562 case TEMPLATE_PARM_INDEX:
15563 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15564 if (tparm == error_mark_node)
15567 if (TEMPLATE_PARM_LEVEL (parm)
15568 != template_decl_level (tparm))
15569 /* The PARM is not one we're trying to unify. Just check
15570 to see if it matches ARG. */
15571 return !(TREE_CODE (arg) == TREE_CODE (parm)
15572 && cp_tree_equal (parm, arg));
15574 idx = TEMPLATE_PARM_IDX (parm);
15575 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15578 return !cp_tree_equal (targ, arg);
15580 /* [temp.deduct.type] If, in the declaration of a function template
15581 with a non-type template-parameter, the non-type
15582 template-parameter is used in an expression in the function
15583 parameter-list and, if the corresponding template-argument is
15584 deduced, the template-argument type shall match the type of the
15585 template-parameter exactly, except that a template-argument
15586 deduced from an array bound may be of any integral type.
15587 The non-type parameter might use already deduced type parameters. */
15588 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
15589 if (!TREE_TYPE (arg))
15590 /* Template-parameter dependent expression. Just accept it for now.
15591 It will later be processed in convert_template_argument. */
15593 else if (same_type_p (TREE_TYPE (arg), tparm))
15595 else if ((strict & UNIFY_ALLOW_INTEGER)
15596 && (TREE_CODE (tparm) == INTEGER_TYPE
15597 || TREE_CODE (tparm) == BOOLEAN_TYPE))
15598 /* Convert the ARG to the type of PARM; the deduced non-type
15599 template argument must exactly match the types of the
15600 corresponding parameter. */
15601 arg = fold (build_nop (tparm, arg));
15602 else if (uses_template_parms (tparm))
15603 /* We haven't deduced the type of this parameter yet. Try again
15609 /* If ARG is a parameter pack or an expansion, we cannot unify
15610 against it unless PARM is also a parameter pack. */
15611 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15612 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
15615 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15620 /* A pointer-to-member constant can be unified only with
15621 another constant. */
15622 if (TREE_CODE (arg) != PTRMEM_CST)
15625 /* Just unify the class member. It would be useless (and possibly
15626 wrong, depending on the strict flags) to unify also
15627 PTRMEM_CST_CLASS, because we want to be sure that both parm and
15628 arg refer to the same variable, even if through different
15629 classes. For instance:
15631 struct A { int x; };
15634 Unification of &A::x and &B::x must succeed. */
15635 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
15636 PTRMEM_CST_MEMBER (arg), strict);
15641 if (TREE_CODE (arg) != POINTER_TYPE)
15644 /* [temp.deduct.call]
15646 A can be another pointer or pointer to member type that can
15647 be converted to the deduced A via a qualification
15648 conversion (_conv.qual_).
15650 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
15651 This will allow for additional cv-qualification of the
15652 pointed-to types if appropriate. */
15654 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
15655 /* The derived-to-base conversion only persists through one
15656 level of pointers. */
15657 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
15659 return unify (tparms, targs, TREE_TYPE (parm),
15660 TREE_TYPE (arg), strict);
15663 case REFERENCE_TYPE:
15664 if (TREE_CODE (arg) != REFERENCE_TYPE)
15666 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15667 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15670 if (TREE_CODE (arg) != ARRAY_TYPE)
15672 if ((TYPE_DOMAIN (parm) == NULL_TREE)
15673 != (TYPE_DOMAIN (arg) == NULL_TREE))
15675 if (TYPE_DOMAIN (parm) != NULL_TREE)
15682 /* Our representation of array types uses "N - 1" as the
15683 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
15684 not an integer constant. We cannot unify arbitrarily
15685 complex expressions, so we eliminate the MINUS_EXPRs
15687 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
15688 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
15691 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
15692 parm_max = TREE_OPERAND (parm_max, 0);
15694 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
15695 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
15698 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
15699 trying to unify the type of a variable with the type
15700 of a template parameter. For example:
15702 template <unsigned int N>
15703 void f (char (&) [N]);
15710 Here, the type of the ARG will be "int [g(i)]", and
15711 may be a SAVE_EXPR, etc. */
15712 if (TREE_CODE (arg_max) != MINUS_EXPR)
15714 arg_max = TREE_OPERAND (arg_max, 0);
15717 /* If only one of the bounds used a MINUS_EXPR, compensate
15718 by adding one to the other bound. */
15719 if (parm_cst && !arg_cst)
15720 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
15724 else if (arg_cst && !parm_cst)
15725 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
15730 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
15733 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15734 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15741 case ENUMERAL_TYPE:
15743 if (TREE_CODE (arg) != TREE_CODE (parm))
15746 /* We have already checked cv-qualification at the top of the
15748 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15751 /* As far as unification is concerned, this wins. Later checks
15752 will invalidate it if necessary. */
15755 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15756 /* Type INTEGER_CST can come from ordinary constant template args. */
15758 while (TREE_CODE (arg) == NOP_EXPR)
15759 arg = TREE_OPERAND (arg, 0);
15761 if (TREE_CODE (arg) != INTEGER_CST)
15763 return !tree_int_cst_equal (parm, arg);
15768 if (TREE_CODE (arg) != TREE_VEC)
15770 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15772 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15773 if (unify (tparms, targs,
15774 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15782 if (TREE_CODE (arg) != TREE_CODE (parm))
15785 if (TYPE_PTRMEMFUNC_P (parm))
15787 if (!TYPE_PTRMEMFUNC_P (arg))
15790 return unify (tparms, targs,
15791 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15792 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15796 if (CLASSTYPE_TEMPLATE_INFO (parm))
15798 tree t = NULL_TREE;
15800 if (strict_in & UNIFY_ALLOW_DERIVED)
15802 /* First, we try to unify the PARM and ARG directly. */
15803 t = try_class_unification (tparms, targs,
15808 /* Fallback to the special case allowed in
15809 [temp.deduct.call]:
15811 If P is a class, and P has the form
15812 template-id, then A can be a derived class of
15813 the deduced A. Likewise, if P is a pointer to
15814 a class of the form template-id, A can be a
15815 pointer to a derived class pointed to by the
15817 t = get_template_base (tparms, targs, parm, arg);
15823 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15824 && (CLASSTYPE_TI_TEMPLATE (parm)
15825 == CLASSTYPE_TI_TEMPLATE (arg)))
15826 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15827 Then, we should unify `int' and `U'. */
15830 /* There's no chance of unification succeeding. */
15833 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15834 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15836 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15841 case FUNCTION_TYPE:
15843 unsigned int nargs;
15848 if (TREE_CODE (arg) != TREE_CODE (parm))
15851 /* CV qualifications for methods can never be deduced, they must
15852 match exactly. We need to check them explicitly here,
15853 because type_unification_real treats them as any other
15854 cv-qualified parameter. */
15855 if (TREE_CODE (parm) == METHOD_TYPE
15856 && (!check_cv_quals_for_unify
15858 class_of_this_parm (arg),
15859 class_of_this_parm (parm))))
15862 if (unify (tparms, targs, TREE_TYPE (parm),
15863 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15866 nargs = list_length (TYPE_ARG_TYPES (arg));
15867 args = XALLOCAVEC (tree, nargs);
15868 for (a = TYPE_ARG_TYPES (arg), i = 0;
15869 a != NULL_TREE && a != void_list_node;
15870 a = TREE_CHAIN (a), ++i)
15871 args[i] = TREE_VALUE (a);
15874 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15875 args, nargs, 1, DEDUCE_EXACT,
15880 /* Unify a pointer to member with a pointer to member function, which
15881 deduces the type of the member as a function type. */
15882 if (TYPE_PTRMEMFUNC_P (arg))
15887 /* Check top-level cv qualifiers */
15888 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15891 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15892 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15895 /* Determine the type of the function we are unifying against. */
15896 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15898 build_function_type (TREE_TYPE (method_type),
15899 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15901 /* Extract the cv-qualifiers of the member function from the
15902 implicit object parameter and place them on the function
15903 type to be restored later. */
15904 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15905 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15908 if (TREE_CODE (arg) != OFFSET_TYPE)
15910 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15911 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15913 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15917 if (DECL_TEMPLATE_PARM_P (parm))
15918 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15919 if (arg != integral_constant_value (parm))
15924 case TEMPLATE_DECL:
15925 /* Matched cases are handled by the ARG == PARM test above. */
15929 /* A non-type template parameter that is a variable should be a
15930 an integral constant, in which case, it whould have been
15931 folded into its (constant) value. So we should not be getting
15932 a variable here. */
15933 gcc_unreachable ();
15935 case TYPE_ARGUMENT_PACK:
15936 case NONTYPE_ARGUMENT_PACK:
15938 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15939 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15940 int i, len = TREE_VEC_LENGTH (packed_parms);
15941 int argslen = TREE_VEC_LENGTH (packed_args);
15942 int parm_variadic_p = 0;
15944 for (i = 0; i < len; ++i)
15946 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15949 /* We can unify against something with a trailing
15951 parm_variadic_p = 1;
15953 /* Since there is something following the pack
15954 expansion, we cannot unify this template argument
15961 /* If we don't have enough arguments to satisfy the parameters
15962 (not counting the pack expression at the end), or we have
15963 too many arguments for a parameter list that doesn't end in
15964 a pack expression, we can't unify. */
15965 if (argslen < (len - parm_variadic_p)
15966 || (argslen > len && !parm_variadic_p))
15969 /* Unify all of the parameters that precede the (optional)
15970 pack expression. */
15971 for (i = 0; i < len - parm_variadic_p; ++i)
15973 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15974 TREE_VEC_ELT (packed_args, i), strict))
15978 if (parm_variadic_p)
15979 return unify_pack_expansion (tparms, targs,
15980 packed_parms, packed_args,
15981 strict, /*call_args_p=*/false,
15989 case DECLTYPE_TYPE:
15990 case UNDERLYING_TYPE:
15991 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
15992 or UNDERLYING_TYPE nodes. */
15996 /* Unification fails if we hit an error node. */
16000 /* An unresolved overload is a nondeduced context. */
16001 if (type_unknown_p (parm))
16003 gcc_assert (EXPR_P (parm));
16005 /* We must be looking at an expression. This can happen with
16009 void foo(S<I>, S<I + 2>);
16011 This is a "nondeduced context":
16015 The nondeduced contexts are:
16017 --A type that is a template-id in which one or more of
16018 the template-arguments is an expression that references
16019 a template-parameter.
16021 In these cases, we assume deduction succeeded, but don't
16022 actually infer any unifications. */
16024 if (!uses_template_parms (parm)
16025 && !template_args_equal (parm, arg))
16032 /* Note that DECL can be defined in this translation unit, if
16036 mark_definable (tree decl)
16039 DECL_NOT_REALLY_EXTERN (decl) = 1;
16040 FOR_EACH_CLONE (clone, decl)
16041 DECL_NOT_REALLY_EXTERN (clone) = 1;
16044 /* Called if RESULT is explicitly instantiated, or is a member of an
16045 explicitly instantiated class. */
16048 mark_decl_instantiated (tree result, int extern_p)
16050 SET_DECL_EXPLICIT_INSTANTIATION (result);
16052 /* If this entity has already been written out, it's too late to
16053 make any modifications. */
16054 if (TREE_ASM_WRITTEN (result))
16057 if (TREE_CODE (result) != FUNCTION_DECL)
16058 /* The TREE_PUBLIC flag for function declarations will have been
16059 set correctly by tsubst. */
16060 TREE_PUBLIC (result) = 1;
16062 /* This might have been set by an earlier implicit instantiation. */
16063 DECL_COMDAT (result) = 0;
16066 DECL_NOT_REALLY_EXTERN (result) = 0;
16069 mark_definable (result);
16070 /* Always make artificials weak. */
16071 if (DECL_ARTIFICIAL (result) && flag_weak)
16072 comdat_linkage (result);
16073 /* For WIN32 we also want to put explicit instantiations in
16074 linkonce sections. */
16075 else if (TREE_PUBLIC (result))
16076 maybe_make_one_only (result);
16079 /* If EXTERN_P, then this function will not be emitted -- unless
16080 followed by an explicit instantiation, at which point its linkage
16081 will be adjusted. If !EXTERN_P, then this function will be
16082 emitted here. In neither circumstance do we want
16083 import_export_decl to adjust the linkage. */
16084 DECL_INTERFACE_KNOWN (result) = 1;
16087 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16088 important template arguments. If any are missing, we check whether
16089 they're important by using error_mark_node for substituting into any
16090 args that were used for partial ordering (the ones between ARGS and END)
16091 and seeing if it bubbles up. */
16094 check_undeduced_parms (tree targs, tree args, tree end)
16096 bool found = false;
16098 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16099 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16102 TREE_VEC_ELT (targs, i) = error_mark_node;
16106 for (; args != end; args = TREE_CHAIN (args))
16108 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16109 if (substed == error_mark_node)
16116 /* Given two function templates PAT1 and PAT2, return:
16118 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16119 -1 if PAT2 is more specialized than PAT1.
16120 0 if neither is more specialized.
16122 LEN indicates the number of parameters we should consider
16123 (defaulted parameters should not be considered).
16125 The 1998 std underspecified function template partial ordering, and
16126 DR214 addresses the issue. We take pairs of arguments, one from
16127 each of the templates, and deduce them against each other. One of
16128 the templates will be more specialized if all the *other*
16129 template's arguments deduce against its arguments and at least one
16130 of its arguments *does* *not* deduce against the other template's
16131 corresponding argument. Deduction is done as for class templates.
16132 The arguments used in deduction have reference and top level cv
16133 qualifiers removed. Iff both arguments were originally reference
16134 types *and* deduction succeeds in both directions, the template
16135 with the more cv-qualified argument wins for that pairing (if
16136 neither is more cv-qualified, they both are equal). Unlike regular
16137 deduction, after all the arguments have been deduced in this way,
16138 we do *not* verify the deduced template argument values can be
16139 substituted into non-deduced contexts.
16141 The logic can be a bit confusing here, because we look at deduce1 and
16142 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16143 can find template arguments for pat1 to make arg1 look like arg2, that
16144 means that arg2 is at least as specialized as arg1. */
16147 more_specialized_fn (tree pat1, tree pat2, int len)
16149 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16150 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16151 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16152 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16153 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16154 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16155 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16156 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16157 tree origs1, origs2;
16158 bool lose1 = false;
16159 bool lose2 = false;
16161 /* Remove the this parameter from non-static member functions. If
16162 one is a non-static member function and the other is not a static
16163 member function, remove the first parameter from that function
16164 also. This situation occurs for operator functions where we
16165 locate both a member function (with this pointer) and non-member
16166 operator (with explicit first operand). */
16167 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16169 len--; /* LEN is the number of significant arguments for DECL1 */
16170 args1 = TREE_CHAIN (args1);
16171 if (!DECL_STATIC_FUNCTION_P (decl2))
16172 args2 = TREE_CHAIN (args2);
16174 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16176 args2 = TREE_CHAIN (args2);
16177 if (!DECL_STATIC_FUNCTION_P (decl1))
16180 args1 = TREE_CHAIN (args1);
16184 /* If only one is a conversion operator, they are unordered. */
16185 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16188 /* Consider the return type for a conversion function */
16189 if (DECL_CONV_FN_P (decl1))
16191 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16192 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16196 processing_template_decl++;
16202 /* Stop when an ellipsis is seen. */
16203 && args1 != NULL_TREE && args2 != NULL_TREE)
16205 tree arg1 = TREE_VALUE (args1);
16206 tree arg2 = TREE_VALUE (args2);
16207 int deduce1, deduce2;
16211 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16212 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16214 /* When both arguments are pack expansions, we need only
16215 unify the patterns themselves. */
16216 arg1 = PACK_EXPANSION_PATTERN (arg1);
16217 arg2 = PACK_EXPANSION_PATTERN (arg2);
16219 /* This is the last comparison we need to do. */
16223 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16225 arg1 = TREE_TYPE (arg1);
16226 quals1 = cp_type_quals (arg1);
16229 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16231 arg2 = TREE_TYPE (arg2);
16232 quals2 = cp_type_quals (arg2);
16235 if ((quals1 < 0) != (quals2 < 0))
16237 /* Only of the args is a reference, see if we should apply
16238 array/function pointer decay to it. This is not part of
16239 DR214, but is, IMHO, consistent with the deduction rules
16240 for the function call itself, and with our earlier
16241 implementation of the underspecified partial ordering
16242 rules. (nathan). */
16245 switch (TREE_CODE (arg1))
16248 arg1 = TREE_TYPE (arg1);
16250 case FUNCTION_TYPE:
16251 arg1 = build_pointer_type (arg1);
16260 switch (TREE_CODE (arg2))
16263 arg2 = TREE_TYPE (arg2);
16265 case FUNCTION_TYPE:
16266 arg2 = build_pointer_type (arg2);
16275 arg1 = TYPE_MAIN_VARIANT (arg1);
16276 arg2 = TYPE_MAIN_VARIANT (arg2);
16278 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16280 int i, len2 = list_length (args2);
16281 tree parmvec = make_tree_vec (1);
16282 tree argvec = make_tree_vec (len2);
16285 /* Setup the parameter vector, which contains only ARG1. */
16286 TREE_VEC_ELT (parmvec, 0) = arg1;
16288 /* Setup the argument vector, which contains the remaining
16290 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16291 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16293 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
16294 argvec, UNIFY_ALLOW_NONE,
16295 /*call_args_p=*/false,
16298 /* We cannot deduce in the other direction, because ARG1 is
16299 a pack expansion but ARG2 is not. */
16302 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16304 int i, len1 = list_length (args1);
16305 tree parmvec = make_tree_vec (1);
16306 tree argvec = make_tree_vec (len1);
16309 /* Setup the parameter vector, which contains only ARG1. */
16310 TREE_VEC_ELT (parmvec, 0) = arg2;
16312 /* Setup the argument vector, which contains the remaining
16314 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16315 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16317 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
16318 argvec, UNIFY_ALLOW_NONE,
16319 /*call_args_p=*/false,
16322 /* We cannot deduce in the other direction, because ARG2 is
16323 a pack expansion but ARG1 is not.*/
16329 /* The normal case, where neither argument is a pack
16331 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
16332 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
16335 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16336 arg2, then arg2 is not as specialized as arg1. */
16342 /* "If, for a given type, deduction succeeds in both directions
16343 (i.e., the types are identical after the transformations above)
16344 and if the type from the argument template is more cv-qualified
16345 than the type from the parameter template (as described above)
16346 that type is considered to be more specialized than the other. If
16347 neither type is more cv-qualified than the other then neither type
16348 is more specialized than the other." */
16350 if (deduce1 && deduce2
16351 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16353 if ((quals1 & quals2) == quals2)
16355 if ((quals1 & quals2) == quals1)
16359 if (lose1 && lose2)
16360 /* We've failed to deduce something in either direction.
16361 These must be unordered. */
16364 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16365 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16366 /* We have already processed all of the arguments in our
16367 handing of the pack expansion type. */
16370 args1 = TREE_CHAIN (args1);
16371 args2 = TREE_CHAIN (args2);
16374 /* "In most cases, all template parameters must have values in order for
16375 deduction to succeed, but for partial ordering purposes a template
16376 parameter may remain without a value provided it is not used in the
16377 types being used for partial ordering."
16379 Thus, if we are missing any of the targs1 we need to substitute into
16380 origs1, then pat2 is not as specialized as pat1. This can happen when
16381 there is a nondeduced context. */
16382 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16384 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16387 processing_template_decl--;
16389 /* All things being equal, if the next argument is a pack expansion
16390 for one function but not for the other, prefer the
16391 non-variadic function. FIXME this is bogus; see c++/41958. */
16393 && args1 && TREE_VALUE (args1)
16394 && args2 && TREE_VALUE (args2))
16396 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16397 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16400 if (lose1 == lose2)
16408 /* Determine which of two partial specializations is more specialized.
16410 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16411 to the first partial specialization. The TREE_VALUE is the
16412 innermost set of template parameters for the partial
16413 specialization. PAT2 is similar, but for the second template.
16415 Return 1 if the first partial specialization is more specialized;
16416 -1 if the second is more specialized; 0 if neither is more
16419 See [temp.class.order] for information about determining which of
16420 two templates is more specialized. */
16423 more_specialized_class (tree pat1, tree pat2)
16428 bool any_deductions = false;
16430 tmpl1 = TREE_TYPE (pat1);
16431 tmpl2 = TREE_TYPE (pat2);
16433 /* Just like what happens for functions, if we are ordering between
16434 different class template specializations, we may encounter dependent
16435 types in the arguments, and we need our dependency check functions
16436 to behave correctly. */
16437 ++processing_template_decl;
16438 targs = get_class_bindings (TREE_VALUE (pat1),
16439 CLASSTYPE_TI_ARGS (tmpl1),
16440 CLASSTYPE_TI_ARGS (tmpl2));
16444 any_deductions = true;
16447 targs = get_class_bindings (TREE_VALUE (pat2),
16448 CLASSTYPE_TI_ARGS (tmpl2),
16449 CLASSTYPE_TI_ARGS (tmpl1));
16453 any_deductions = true;
16455 --processing_template_decl;
16457 /* In the case of a tie where at least one of the class templates
16458 has a parameter pack at the end, the template with the most
16459 non-packed parameters wins. */
16462 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16463 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16465 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16466 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16467 int len1 = TREE_VEC_LENGTH (args1);
16468 int len2 = TREE_VEC_LENGTH (args2);
16470 /* We don't count the pack expansion at the end. */
16471 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16473 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16478 else if (len1 < len2)
16485 /* Return the template arguments that will produce the function signature
16486 DECL from the function template FN, with the explicit template
16487 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16488 also match. Return NULL_TREE if no satisfactory arguments could be
16492 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16494 int ntparms = DECL_NTPARMS (fn);
16495 tree targs = make_tree_vec (ntparms);
16497 tree decl_arg_types;
16499 unsigned int nargs, ix;
16502 /* Substitute the explicit template arguments into the type of DECL.
16503 The call to fn_type_unification will handle substitution into the
16505 decl_type = TREE_TYPE (decl);
16506 if (explicit_args && uses_template_parms (decl_type))
16509 tree converted_args;
16511 if (DECL_TEMPLATE_INFO (decl))
16512 tmpl = DECL_TI_TEMPLATE (decl);
16514 /* We can get here for some invalid specializations. */
16518 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16519 explicit_args, NULL_TREE,
16521 /*require_all_args=*/false,
16522 /*use_default_args=*/false);
16523 if (converted_args == error_mark_node)
16526 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16527 if (decl_type == error_mark_node)
16531 /* Never do unification on the 'this' parameter. */
16532 decl_arg_types = skip_artificial_parms_for (decl,
16533 TYPE_ARG_TYPES (decl_type));
16535 nargs = list_length (decl_arg_types);
16536 args = XALLOCAVEC (tree, nargs);
16537 for (arg = decl_arg_types, ix = 0;
16538 arg != NULL_TREE && arg != void_list_node;
16539 arg = TREE_CHAIN (arg), ++ix)
16540 args[ix] = TREE_VALUE (arg);
16542 if (fn_type_unification (fn, explicit_args, targs,
16544 (check_rettype || DECL_CONV_FN_P (fn)
16545 ? TREE_TYPE (decl_type) : NULL_TREE),
16546 DEDUCE_EXACT, LOOKUP_NORMAL))
16552 /* Return the innermost template arguments that, when applied to a
16553 template specialization whose innermost template parameters are
16554 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
16557 For example, suppose we have:
16559 template <class T, class U> struct S {};
16560 template <class T> struct S<T*, int> {};
16562 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
16563 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
16564 int}. The resulting vector will be {double}, indicating that `T'
16565 is bound to `double'. */
16568 get_class_bindings (tree tparms, tree spec_args, tree args)
16570 int i, ntparms = TREE_VEC_LENGTH (tparms);
16572 tree innermost_deduced_args;
16574 innermost_deduced_args = make_tree_vec (ntparms);
16575 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16577 deduced_args = copy_node (args);
16578 SET_TMPL_ARGS_LEVEL (deduced_args,
16579 TMPL_ARGS_DEPTH (deduced_args),
16580 innermost_deduced_args);
16583 deduced_args = innermost_deduced_args;
16585 if (unify (tparms, deduced_args,
16586 INNERMOST_TEMPLATE_ARGS (spec_args),
16587 INNERMOST_TEMPLATE_ARGS (args),
16591 for (i = 0; i < ntparms; ++i)
16592 if (! TREE_VEC_ELT (innermost_deduced_args, i))
16595 /* Verify that nondeduced template arguments agree with the type
16596 obtained from argument deduction.
16600 struct A { typedef int X; };
16601 template <class T, class U> struct C {};
16602 template <class T> struct C<T, typename T::X> {};
16604 Then with the instantiation `C<A, int>', we can deduce that
16605 `T' is `A' but unify () does not check whether `typename T::X'
16607 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
16608 if (spec_args == error_mark_node
16609 /* We only need to check the innermost arguments; the other
16610 arguments will always agree. */
16611 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
16612 INNERMOST_TEMPLATE_ARGS (args)))
16615 /* Now that we have bindings for all of the template arguments,
16616 ensure that the arguments deduced for the template template
16617 parameters have compatible template parameter lists. See the use
16618 of template_template_parm_bindings_ok_p in fn_type_unification
16619 for more information. */
16620 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
16623 return deduced_args;
16626 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
16627 Return the TREE_LIST node with the most specialized template, if
16628 any. If there is no most specialized template, the error_mark_node
16631 Note that this function does not look at, or modify, the
16632 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
16633 returned is one of the elements of INSTANTIATIONS, callers may
16634 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
16635 and retrieve it from the value returned. */
16638 most_specialized_instantiation (tree templates)
16642 ++processing_template_decl;
16645 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
16649 if (get_bindings (TREE_VALUE (champ),
16650 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16651 NULL_TREE, /*check_ret=*/false))
16654 if (get_bindings (TREE_VALUE (fn),
16655 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16656 NULL_TREE, /*check_ret=*/false))
16663 /* Equally specialized, move to next function. If there
16664 is no next function, nothing's most specialized. */
16665 fn = TREE_CHAIN (fn);
16673 /* Now verify that champ is better than everything earlier in the
16674 instantiation list. */
16675 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
16676 if (get_bindings (TREE_VALUE (champ),
16677 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16678 NULL_TREE, /*check_ret=*/false)
16679 || !get_bindings (TREE_VALUE (fn),
16680 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16681 NULL_TREE, /*check_ret=*/false))
16687 processing_template_decl--;
16690 return error_mark_node;
16695 /* If DECL is a specialization of some template, return the most
16696 general such template. Otherwise, returns NULL_TREE.
16698 For example, given:
16700 template <class T> struct S { template <class U> void f(U); };
16702 if TMPL is `template <class U> void S<int>::f(U)' this will return
16703 the full template. This function will not trace past partial
16704 specializations, however. For example, given in addition:
16706 template <class T> struct S<T*> { template <class U> void f(U); };
16708 if TMPL is `template <class U> void S<int*>::f(U)' this will return
16709 `template <class T> template <class U> S<T*>::f(U)'. */
16712 most_general_template (tree decl)
16714 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
16715 an immediate specialization. */
16716 if (TREE_CODE (decl) == FUNCTION_DECL)
16718 if (DECL_TEMPLATE_INFO (decl)) {
16719 decl = DECL_TI_TEMPLATE (decl);
16721 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
16722 template friend. */
16723 if (TREE_CODE (decl) != TEMPLATE_DECL)
16729 /* Look for more and more general templates. */
16730 while (DECL_TEMPLATE_INFO (decl))
16732 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
16733 (See cp-tree.h for details.) */
16734 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
16737 if (CLASS_TYPE_P (TREE_TYPE (decl))
16738 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
16741 /* Stop if we run into an explicitly specialized class template. */
16742 if (!DECL_NAMESPACE_SCOPE_P (decl)
16743 && DECL_CONTEXT (decl)
16744 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16747 decl = DECL_TI_TEMPLATE (decl);
16753 /* Return the most specialized of the class template partial
16754 specializations of TMPL which can produce TYPE, a specialization of
16755 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16756 a _TYPE node corresponding to the partial specialization, while the
16757 TREE_PURPOSE is the set of template arguments that must be
16758 substituted into the TREE_TYPE in order to generate TYPE.
16760 If the choice of partial specialization is ambiguous, a diagnostic
16761 is issued, and the error_mark_node is returned. If there are no
16762 partial specializations of TMPL matching TYPE, then NULL_TREE is
16766 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16768 tree list = NULL_TREE;
16774 tree outer_args = NULL_TREE;
16776 tmpl = most_general_template (tmpl);
16777 args = CLASSTYPE_TI_ARGS (type);
16779 /* For determining which partial specialization to use, only the
16780 innermost args are interesting. */
16781 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16783 outer_args = strip_innermost_template_args (args, 1);
16784 args = INNERMOST_TEMPLATE_ARGS (args);
16787 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16789 tree partial_spec_args;
16791 tree parms = TREE_VALUE (t);
16793 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16795 ++processing_template_decl;
16801 /* Discard the outer levels of args, and then substitute in the
16802 template args from the enclosing class. */
16803 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16804 partial_spec_args = tsubst_template_args
16805 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16807 /* PARMS already refers to just the innermost parms, but the
16808 template parms in partial_spec_args had their levels lowered
16809 by tsubst, so we need to do the same for the parm list. We
16810 can't just tsubst the TREE_VEC itself, as tsubst wants to
16811 treat a TREE_VEC as an argument vector. */
16812 parms = copy_node (parms);
16813 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16814 TREE_VEC_ELT (parms, i) =
16815 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16819 partial_spec_args =
16820 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16821 add_to_template_args (outer_args,
16822 partial_spec_args),
16824 /*require_all_args=*/true,
16825 /*use_default_args=*/true);
16827 --processing_template_decl;
16829 if (partial_spec_args == error_mark_node)
16830 return error_mark_node;
16832 spec_args = get_class_bindings (parms,
16838 spec_args = add_to_template_args (outer_args, spec_args);
16839 list = tree_cons (spec_args, TREE_VALUE (t), list);
16840 TREE_TYPE (list) = TREE_TYPE (t);
16847 ambiguous_p = false;
16850 t = TREE_CHAIN (t);
16851 for (; t; t = TREE_CHAIN (t))
16853 fate = more_specialized_class (champ, t);
16860 t = TREE_CHAIN (t);
16863 ambiguous_p = true;
16872 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16874 fate = more_specialized_class (champ, t);
16877 ambiguous_p = true;
16885 char *spaces = NULL;
16886 if (!(complain & tf_error))
16887 return error_mark_node;
16888 error ("ambiguous class template instantiation for %q#T", type);
16889 str = ngettext ("candidate is:", "candidates are:", list_length (list));
16890 for (t = list; t; t = TREE_CHAIN (t))
16892 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16893 spaces = spaces ? spaces : get_spaces (str);
16896 return error_mark_node;
16902 /* Explicitly instantiate DECL. */
16905 do_decl_instantiation (tree decl, tree storage)
16907 tree result = NULL_TREE;
16910 if (!decl || decl == error_mark_node)
16911 /* An error occurred, for which grokdeclarator has already issued
16912 an appropriate message. */
16914 else if (! DECL_LANG_SPECIFIC (decl))
16916 error ("explicit instantiation of non-template %q#D", decl);
16919 else if (TREE_CODE (decl) == VAR_DECL)
16921 /* There is an asymmetry here in the way VAR_DECLs and
16922 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16923 the latter, the DECL we get back will be marked as a
16924 template instantiation, and the appropriate
16925 DECL_TEMPLATE_INFO will be set up. This does not happen for
16926 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16927 should handle VAR_DECLs as it currently handles
16929 if (!DECL_CLASS_SCOPE_P (decl))
16931 error ("%qD is not a static data member of a class template", decl);
16934 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16935 if (!result || TREE_CODE (result) != VAR_DECL)
16937 error ("no matching template for %qD found", decl);
16940 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16942 error ("type %qT for explicit instantiation %qD does not match "
16943 "declared type %qT", TREE_TYPE (result), decl,
16948 else if (TREE_CODE (decl) != FUNCTION_DECL)
16950 error ("explicit instantiation of %q#D", decl);
16956 /* Check for various error cases. Note that if the explicit
16957 instantiation is valid the RESULT will currently be marked as an
16958 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16959 until we get here. */
16961 if (DECL_TEMPLATE_SPECIALIZATION (result))
16963 /* DR 259 [temp.spec].
16965 Both an explicit instantiation and a declaration of an explicit
16966 specialization shall not appear in a program unless the explicit
16967 instantiation follows a declaration of the explicit specialization.
16969 For a given set of template parameters, if an explicit
16970 instantiation of a template appears after a declaration of an
16971 explicit specialization for that template, the explicit
16972 instantiation has no effect. */
16975 else if (DECL_EXPLICIT_INSTANTIATION (result))
16979 No program shall explicitly instantiate any template more
16982 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16983 the first instantiation was `extern' and the second is not,
16984 and EXTERN_P for the opposite case. */
16985 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16986 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16987 /* If an "extern" explicit instantiation follows an ordinary
16988 explicit instantiation, the template is instantiated. */
16992 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16994 error ("no matching template for %qD found", result);
16997 else if (!DECL_TEMPLATE_INFO (result))
16999 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17003 if (storage == NULL_TREE)
17005 else if (storage == ridpointers[(int) RID_EXTERN])
17007 if (!in_system_header && (cxx_dialect == cxx98))
17008 pedwarn (input_location, OPT_pedantic,
17009 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17014 error ("storage class %qD applied to template instantiation", storage);
17016 check_explicit_instantiation_namespace (result);
17017 mark_decl_instantiated (result, extern_p);
17019 instantiate_decl (result, /*defer_ok=*/1,
17020 /*expl_inst_class_mem_p=*/false);
17024 mark_class_instantiated (tree t, int extern_p)
17026 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17027 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17028 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17029 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17032 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17033 rest_of_type_compilation (t, 1);
17037 /* Called from do_type_instantiation through binding_table_foreach to
17038 do recursive instantiation for the type bound in ENTRY. */
17040 bt_instantiate_type_proc (binding_entry entry, void *data)
17042 tree storage = *(tree *) data;
17044 if (MAYBE_CLASS_TYPE_P (entry->type)
17045 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17046 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17049 /* Called from do_type_instantiation to instantiate a member
17050 (a member function or a static member variable) of an
17051 explicitly instantiated class template. */
17053 instantiate_class_member (tree decl, int extern_p)
17055 mark_decl_instantiated (decl, extern_p);
17057 instantiate_decl (decl, /*defer_ok=*/1,
17058 /*expl_inst_class_mem_p=*/true);
17061 /* Perform an explicit instantiation of template class T. STORAGE, if
17062 non-null, is the RID for extern, inline or static. COMPLAIN is
17063 nonzero if this is called from the parser, zero if called recursively,
17064 since the standard is unclear (as detailed below). */
17067 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17072 int previous_instantiation_extern_p = 0;
17074 if (TREE_CODE (t) == TYPE_DECL)
17077 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17079 error ("explicit instantiation of non-template type %qT", t);
17085 if (!COMPLETE_TYPE_P (t))
17087 if (complain & tf_error)
17088 error ("explicit instantiation of %q#T before definition of template",
17093 if (storage != NULL_TREE)
17095 if (!in_system_header)
17097 if (storage == ridpointers[(int) RID_EXTERN])
17099 if (cxx_dialect == cxx98)
17100 pedwarn (input_location, OPT_pedantic,
17101 "ISO C++ 1998 forbids the use of %<extern%> on "
17102 "explicit instantiations");
17105 pedwarn (input_location, OPT_pedantic,
17106 "ISO C++ forbids the use of %qE"
17107 " on explicit instantiations", storage);
17110 if (storage == ridpointers[(int) RID_INLINE])
17112 else if (storage == ridpointers[(int) RID_EXTERN])
17114 else if (storage == ridpointers[(int) RID_STATIC])
17118 error ("storage class %qD applied to template instantiation",
17124 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17126 /* DR 259 [temp.spec].
17128 Both an explicit instantiation and a declaration of an explicit
17129 specialization shall not appear in a program unless the explicit
17130 instantiation follows a declaration of the explicit specialization.
17132 For a given set of template parameters, if an explicit
17133 instantiation of a template appears after a declaration of an
17134 explicit specialization for that template, the explicit
17135 instantiation has no effect. */
17138 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17142 No program shall explicitly instantiate any template more
17145 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17146 instantiation was `extern'. If EXTERN_P then the second is.
17147 These cases are OK. */
17148 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17150 if (!previous_instantiation_extern_p && !extern_p
17151 && (complain & tf_error))
17152 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17154 /* If we've already instantiated the template, just return now. */
17155 if (!CLASSTYPE_INTERFACE_ONLY (t))
17159 check_explicit_instantiation_namespace (TYPE_NAME (t));
17160 mark_class_instantiated (t, extern_p);
17168 /* In contrast to implicit instantiation, where only the
17169 declarations, and not the definitions, of members are
17170 instantiated, we have here:
17174 The explicit instantiation of a class template specialization
17175 implies the instantiation of all of its members not
17176 previously explicitly specialized in the translation unit
17177 containing the explicit instantiation.
17179 Of course, we can't instantiate member template classes, since
17180 we don't have any arguments for them. Note that the standard
17181 is unclear on whether the instantiation of the members are
17182 *explicit* instantiations or not. However, the most natural
17183 interpretation is that it should be an explicit instantiation. */
17186 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17187 if (TREE_CODE (tmp) == FUNCTION_DECL
17188 && DECL_TEMPLATE_INSTANTIATION (tmp))
17189 instantiate_class_member (tmp, extern_p);
17191 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17192 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17193 instantiate_class_member (tmp, extern_p);
17195 if (CLASSTYPE_NESTED_UTDS (t))
17196 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17197 bt_instantiate_type_proc, &storage);
17201 /* Given a function DECL, which is a specialization of TMPL, modify
17202 DECL to be a re-instantiation of TMPL with the same template
17203 arguments. TMPL should be the template into which tsubst'ing
17204 should occur for DECL, not the most general template.
17206 One reason for doing this is a scenario like this:
17209 void f(const T&, int i);
17211 void g() { f(3, 7); }
17214 void f(const T& t, const int i) { }
17216 Note that when the template is first instantiated, with
17217 instantiate_template, the resulting DECL will have no name for the
17218 first parameter, and the wrong type for the second. So, when we go
17219 to instantiate the DECL, we regenerate it. */
17222 regenerate_decl_from_template (tree decl, tree tmpl)
17224 /* The arguments used to instantiate DECL, from the most general
17229 args = DECL_TI_ARGS (decl);
17230 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17232 /* Make sure that we can see identifiers, and compute access
17234 push_access_scope (decl);
17236 if (TREE_CODE (decl) == FUNCTION_DECL)
17244 args_depth = TMPL_ARGS_DEPTH (args);
17245 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17246 if (args_depth > parms_depth)
17247 args = get_innermost_template_args (args, parms_depth);
17249 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17250 args, tf_error, NULL_TREE);
17252 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17255 /* Merge parameter declarations. */
17256 decl_parm = skip_artificial_parms_for (decl,
17257 DECL_ARGUMENTS (decl));
17259 = skip_artificial_parms_for (code_pattern,
17260 DECL_ARGUMENTS (code_pattern));
17261 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17266 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17267 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17268 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17270 parm_type = type_decays_to (parm_type);
17271 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17272 TREE_TYPE (decl_parm) = parm_type;
17273 attributes = DECL_ATTRIBUTES (pattern_parm);
17274 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17276 DECL_ATTRIBUTES (decl_parm) = attributes;
17277 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17279 decl_parm = DECL_CHAIN (decl_parm);
17280 pattern_parm = DECL_CHAIN (pattern_parm);
17282 /* Merge any parameters that match with the function parameter
17284 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17287 tree expanded_types;
17288 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17289 the parameters in this function parameter pack. */
17290 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17291 args, tf_error, NULL_TREE);
17292 len = TREE_VEC_LENGTH (expanded_types);
17293 for (i = 0; i < len; i++)
17298 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17299 /* Rename the parameter to include the index. */
17300 DECL_NAME (decl_parm) =
17301 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17302 parm_type = TREE_VEC_ELT (expanded_types, i);
17303 parm_type = type_decays_to (parm_type);
17304 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17305 TREE_TYPE (decl_parm) = parm_type;
17306 attributes = DECL_ATTRIBUTES (pattern_parm);
17307 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17309 DECL_ATTRIBUTES (decl_parm) = attributes;
17310 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17312 decl_parm = DECL_CHAIN (decl_parm);
17315 /* Merge additional specifiers from the CODE_PATTERN. */
17316 if (DECL_DECLARED_INLINE_P (code_pattern)
17317 && !DECL_DECLARED_INLINE_P (decl))
17318 DECL_DECLARED_INLINE_P (decl) = 1;
17320 else if (TREE_CODE (decl) == VAR_DECL)
17322 DECL_INITIAL (decl) =
17323 tsubst_expr (DECL_INITIAL (code_pattern), args,
17324 tf_error, DECL_TI_TEMPLATE (decl),
17325 /*integral_constant_expression_p=*/false);
17326 if (VAR_HAD_UNKNOWN_BOUND (decl))
17327 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17328 tf_error, DECL_TI_TEMPLATE (decl));
17331 gcc_unreachable ();
17333 pop_access_scope (decl);
17336 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17337 substituted to get DECL. */
17340 template_for_substitution (tree decl)
17342 tree tmpl = DECL_TI_TEMPLATE (decl);
17344 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17345 for the instantiation. This is not always the most general
17346 template. Consider, for example:
17349 struct S { template <class U> void f();
17350 template <> void f<int>(); };
17352 and an instantiation of S<double>::f<int>. We want TD to be the
17353 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17354 while (/* An instantiation cannot have a definition, so we need a
17355 more general template. */
17356 DECL_TEMPLATE_INSTANTIATION (tmpl)
17357 /* We must also deal with friend templates. Given:
17359 template <class T> struct S {
17360 template <class U> friend void f() {};
17363 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17364 so far as the language is concerned, but that's still
17365 where we get the pattern for the instantiation from. On
17366 other hand, if the definition comes outside the class, say:
17368 template <class T> struct S {
17369 template <class U> friend void f();
17371 template <class U> friend void f() {}
17373 we don't need to look any further. That's what the check for
17374 DECL_INITIAL is for. */
17375 || (TREE_CODE (decl) == FUNCTION_DECL
17376 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17377 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17379 /* The present template, TD, should not be a definition. If it
17380 were a definition, we should be using it! Note that we
17381 cannot restructure the loop to just keep going until we find
17382 a template with a definition, since that might go too far if
17383 a specialization was declared, but not defined. */
17384 gcc_assert (TREE_CODE (decl) != VAR_DECL
17385 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17387 /* Fetch the more general template. */
17388 tmpl = DECL_TI_TEMPLATE (tmpl);
17394 /* Returns true if we need to instantiate this template instance even if we
17395 know we aren't going to emit it.. */
17398 always_instantiate_p (tree decl)
17400 /* We always instantiate inline functions so that we can inline them. An
17401 explicit instantiation declaration prohibits implicit instantiation of
17402 non-inline functions. With high levels of optimization, we would
17403 normally inline non-inline functions -- but we're not allowed to do
17404 that for "extern template" functions. Therefore, we check
17405 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17406 return ((TREE_CODE (decl) == FUNCTION_DECL
17407 && DECL_DECLARED_INLINE_P (decl))
17408 /* And we need to instantiate static data members so that
17409 their initializers are available in integral constant
17411 || (TREE_CODE (decl) == VAR_DECL
17412 && decl_maybe_constant_var_p (decl)));
17415 /* Produce the definition of D, a _DECL generated from a template. If
17416 DEFER_OK is nonzero, then we don't have to actually do the
17417 instantiation now; we just have to do it sometime. Normally it is
17418 an error if this is an explicit instantiation but D is undefined.
17419 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17420 explicitly instantiated class template. */
17423 instantiate_decl (tree d, int defer_ok,
17424 bool expl_inst_class_mem_p)
17426 tree tmpl = DECL_TI_TEMPLATE (d);
17433 bool pattern_defined;
17435 location_t saved_loc = input_location;
17438 /* This function should only be used to instantiate templates for
17439 functions and static member variables. */
17440 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17441 || TREE_CODE (d) == VAR_DECL);
17443 /* Variables are never deferred; if instantiation is required, they
17444 are instantiated right away. That allows for better code in the
17445 case that an expression refers to the value of the variable --
17446 if the variable has a constant value the referring expression can
17447 take advantage of that fact. */
17448 if (TREE_CODE (d) == VAR_DECL
17449 || DECL_DECLARED_CONSTEXPR_P (d))
17452 /* Don't instantiate cloned functions. Instead, instantiate the
17453 functions they cloned. */
17454 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17455 d = DECL_CLONED_FUNCTION (d);
17457 if (DECL_TEMPLATE_INSTANTIATED (d)
17458 || DECL_TEMPLATE_SPECIALIZATION (d))
17459 /* D has already been instantiated or explicitly specialized, so
17460 there's nothing for us to do here.
17462 It might seem reasonable to check whether or not D is an explicit
17463 instantiation, and, if so, stop here. But when an explicit
17464 instantiation is deferred until the end of the compilation,
17465 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17466 the instantiation. */
17469 /* Check to see whether we know that this template will be
17470 instantiated in some other file, as with "extern template"
17472 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17474 /* In general, we do not instantiate such templates. */
17475 if (external_p && !always_instantiate_p (d))
17478 gen_tmpl = most_general_template (tmpl);
17479 gen_args = DECL_TI_ARGS (d);
17481 if (tmpl != gen_tmpl)
17482 /* We should already have the extra args. */
17483 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17484 == TMPL_ARGS_DEPTH (gen_args));
17485 /* And what's in the hash table should match D. */
17486 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17487 || spec == NULL_TREE);
17489 /* This needs to happen before any tsubsting. */
17490 if (! push_tinst_level (d))
17493 timevar_push (TV_TEMPLATE_INST);
17495 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
17496 for the instantiation. */
17497 td = template_for_substitution (d);
17498 code_pattern = DECL_TEMPLATE_RESULT (td);
17500 /* We should never be trying to instantiate a member of a class
17501 template or partial specialization. */
17502 gcc_assert (d != code_pattern);
17504 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
17505 || DECL_TEMPLATE_SPECIALIZATION (td))
17506 /* In the case of a friend template whose definition is provided
17507 outside the class, we may have too many arguments. Drop the
17508 ones we don't need. The same is true for specializations. */
17509 args = get_innermost_template_args
17510 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
17514 if (TREE_CODE (d) == FUNCTION_DECL)
17515 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
17516 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
17518 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
17520 /* We may be in the middle of deferred access check. Disable it now. */
17521 push_deferring_access_checks (dk_no_deferred);
17523 /* Unless an explicit instantiation directive has already determined
17524 the linkage of D, remember that a definition is available for
17526 if (pattern_defined
17527 && !DECL_INTERFACE_KNOWN (d)
17528 && !DECL_NOT_REALLY_EXTERN (d))
17529 mark_definable (d);
17531 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
17532 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
17533 input_location = DECL_SOURCE_LOCATION (d);
17535 /* If D is a member of an explicitly instantiated class template,
17536 and no definition is available, treat it like an implicit
17538 if (!pattern_defined && expl_inst_class_mem_p
17539 && DECL_EXPLICIT_INSTANTIATION (d))
17541 /* Leave linkage flags alone on instantiations with anonymous
17543 if (TREE_PUBLIC (d))
17545 DECL_NOT_REALLY_EXTERN (d) = 0;
17546 DECL_INTERFACE_KNOWN (d) = 0;
17548 SET_DECL_IMPLICIT_INSTANTIATION (d);
17551 /* Recheck the substitutions to obtain any warning messages
17552 about ignoring cv qualifiers. Don't do this for artificial decls,
17553 as it breaks the context-sensitive substitution for lambda op(). */
17554 if (!defer_ok && !DECL_ARTIFICIAL (d))
17556 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
17557 tree type = TREE_TYPE (gen);
17559 /* Make sure that we can see identifiers, and compute access
17560 correctly. D is already the target FUNCTION_DECL with the
17562 push_access_scope (d);
17564 if (TREE_CODE (gen) == FUNCTION_DECL)
17566 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
17567 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
17569 /* Don't simply tsubst the function type, as that will give
17570 duplicate warnings about poor parameter qualifications.
17571 The function arguments are the same as the decl_arguments
17572 without the top level cv qualifiers. */
17573 type = TREE_TYPE (type);
17575 tsubst (type, gen_args, tf_warning_or_error, d);
17577 pop_access_scope (d);
17580 /* Defer all other templates, unless we have been explicitly
17581 forbidden from doing so. */
17582 if (/* If there is no definition, we cannot instantiate the
17585 /* If it's OK to postpone instantiation, do so. */
17587 /* If this is a static data member that will be defined
17588 elsewhere, we don't want to instantiate the entire data
17589 member, but we do want to instantiate the initializer so that
17590 we can substitute that elsewhere. */
17591 || (external_p && TREE_CODE (d) == VAR_DECL))
17593 /* The definition of the static data member is now required so
17594 we must substitute the initializer. */
17595 if (TREE_CODE (d) == VAR_DECL
17596 && !DECL_INITIAL (d)
17597 && DECL_INITIAL (code_pattern))
17601 bool const_init = false;
17603 ns = decl_namespace_context (d);
17604 push_nested_namespace (ns);
17605 push_nested_class (DECL_CONTEXT (d));
17606 init = tsubst_expr (DECL_INITIAL (code_pattern),
17608 tf_warning_or_error, NULL_TREE,
17609 /*integral_constant_expression_p=*/false);
17610 /* Make sure the initializer is still constant, in case of
17611 circular dependency (template/instantiate6.C). */
17613 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17614 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
17615 /*asmspec_tree=*/NULL_TREE,
17616 LOOKUP_ONLYCONVERTING);
17617 pop_nested_class ();
17618 pop_nested_namespace (ns);
17621 /* We restore the source position here because it's used by
17622 add_pending_template. */
17623 input_location = saved_loc;
17625 if (at_eof && !pattern_defined
17626 && DECL_EXPLICIT_INSTANTIATION (d)
17627 && DECL_NOT_REALLY_EXTERN (d))
17630 The definition of a non-exported function template, a
17631 non-exported member function template, or a non-exported
17632 member function or static data member of a class template
17633 shall be present in every translation unit in which it is
17634 explicitly instantiated. */
17635 permerror (input_location, "explicit instantiation of %qD "
17636 "but no definition available", d);
17638 /* If we're in unevaluated context, we just wanted to get the
17639 constant value; this isn't an odr use, so don't queue
17640 a full instantiation. */
17641 if (cp_unevaluated_operand != 0)
17643 /* ??? Historically, we have instantiated inline functions, even
17644 when marked as "extern template". */
17645 if (!(external_p && TREE_CODE (d) == VAR_DECL))
17646 add_pending_template (d);
17649 /* Tell the repository that D is available in this translation unit
17650 -- and see if it is supposed to be instantiated here. */
17651 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
17653 /* In a PCH file, despite the fact that the repository hasn't
17654 requested instantiation in the PCH it is still possible that
17655 an instantiation will be required in a file that includes the
17658 add_pending_template (d);
17659 /* Instantiate inline functions so that the inliner can do its
17660 job, even though we'll not be emitting a copy of this
17662 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
17666 need_push = !cfun || !global_bindings_p ();
17668 push_to_top_level ();
17670 /* Mark D as instantiated so that recursive calls to
17671 instantiate_decl do not try to instantiate it again. */
17672 DECL_TEMPLATE_INSTANTIATED (d) = 1;
17674 /* Regenerate the declaration in case the template has been modified
17675 by a subsequent redeclaration. */
17676 regenerate_decl_from_template (d, td);
17678 /* We already set the file and line above. Reset them now in case
17679 they changed as a result of calling regenerate_decl_from_template. */
17680 input_location = DECL_SOURCE_LOCATION (d);
17682 if (TREE_CODE (d) == VAR_DECL)
17685 bool const_init = false;
17687 /* Clear out DECL_RTL; whatever was there before may not be right
17688 since we've reset the type of the declaration. */
17689 SET_DECL_RTL (d, NULL);
17690 DECL_IN_AGGR_P (d) = 0;
17692 /* The initializer is placed in DECL_INITIAL by
17693 regenerate_decl_from_template so we don't need to
17694 push/pop_access_scope again here. Pull it out so that
17695 cp_finish_decl can process it. */
17696 init = DECL_INITIAL (d);
17697 DECL_INITIAL (d) = NULL_TREE;
17698 DECL_INITIALIZED_P (d) = 0;
17700 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
17701 initializer. That function will defer actual emission until
17702 we have a chance to determine linkage. */
17703 DECL_EXTERNAL (d) = 0;
17705 /* Enter the scope of D so that access-checking works correctly. */
17706 push_nested_class (DECL_CONTEXT (d));
17707 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17708 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
17709 pop_nested_class ();
17711 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
17712 synthesize_method (d);
17713 else if (TREE_CODE (d) == FUNCTION_DECL)
17715 htab_t saved_local_specializations;
17720 /* Save away the current list, in case we are instantiating one
17721 template from within the body of another. */
17722 saved_local_specializations = local_specializations;
17724 /* Set up the list of local specializations. */
17725 local_specializations = htab_create (37,
17726 hash_local_specialization,
17727 eq_local_specializations,
17730 /* Set up context. */
17731 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
17733 /* Create substitution entries for the parameters. */
17734 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
17735 tmpl_parm = DECL_ARGUMENTS (subst_decl);
17736 spec_parm = DECL_ARGUMENTS (d);
17737 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
17739 register_local_specialization (spec_parm, tmpl_parm);
17740 spec_parm = skip_artificial_parms_for (d, spec_parm);
17741 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
17743 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17745 register_local_specialization (spec_parm, tmpl_parm);
17746 tmpl_parm = DECL_CHAIN (tmpl_parm);
17747 spec_parm = DECL_CHAIN (spec_parm);
17749 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17751 /* Register the (value) argument pack as a specialization of
17752 TMPL_PARM, then move on. */
17753 tree argpack = make_fnparm_pack (spec_parm);
17754 register_local_specialization (argpack, tmpl_parm);
17755 tmpl_parm = DECL_CHAIN (tmpl_parm);
17756 spec_parm = NULL_TREE;
17758 gcc_assert (!spec_parm);
17760 /* Substitute into the body of the function. */
17761 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
17762 tf_warning_or_error, tmpl,
17763 /*integral_constant_expression_p=*/false);
17765 /* Set the current input_location to the end of the function
17766 so that finish_function knows where we are. */
17767 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17769 /* We don't need the local specializations any more. */
17770 htab_delete (local_specializations);
17771 local_specializations = saved_local_specializations;
17773 /* Finish the function. */
17774 d = finish_function (0);
17775 expand_or_defer_fn (d);
17778 /* We're not deferring instantiation any more. */
17779 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17782 pop_from_top_level ();
17785 input_location = saved_loc;
17786 pop_deferring_access_checks ();
17787 pop_tinst_level ();
17789 timevar_pop (TV_TEMPLATE_INST);
17794 /* Run through the list of templates that we wish we could
17795 instantiate, and instantiate any we can. RETRIES is the
17796 number of times we retry pending template instantiation. */
17799 instantiate_pending_templates (int retries)
17802 location_t saved_loc = input_location;
17804 /* Instantiating templates may trigger vtable generation. This in turn
17805 may require further template instantiations. We place a limit here
17806 to avoid infinite loop. */
17807 if (pending_templates && retries >= max_tinst_depth)
17809 tree decl = pending_templates->tinst->decl;
17811 error ("template instantiation depth exceeds maximum of %d"
17812 " instantiating %q+D, possibly from virtual table generation"
17813 " (use -ftemplate-depth= to increase the maximum)",
17814 max_tinst_depth, decl);
17815 if (TREE_CODE (decl) == FUNCTION_DECL)
17816 /* Pretend that we defined it. */
17817 DECL_INITIAL (decl) = error_mark_node;
17823 struct pending_template **t = &pending_templates;
17824 struct pending_template *last = NULL;
17828 tree instantiation = reopen_tinst_level ((*t)->tinst);
17829 bool complete = false;
17831 if (TYPE_P (instantiation))
17835 if (!COMPLETE_TYPE_P (instantiation))
17837 instantiate_class_template (instantiation);
17838 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17839 for (fn = TYPE_METHODS (instantiation);
17841 fn = TREE_CHAIN (fn))
17842 if (! DECL_ARTIFICIAL (fn))
17843 instantiate_decl (fn,
17845 /*expl_inst_class_mem_p=*/false);
17846 if (COMPLETE_TYPE_P (instantiation))
17850 complete = COMPLETE_TYPE_P (instantiation);
17854 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17855 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17858 = instantiate_decl (instantiation,
17860 /*expl_inst_class_mem_p=*/false);
17861 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17865 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17866 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17870 /* If INSTANTIATION has been instantiated, then we don't
17871 need to consider it again in the future. */
17879 current_tinst_level = NULL;
17881 last_pending_template = last;
17883 while (reconsider);
17885 input_location = saved_loc;
17888 /* Substitute ARGVEC into T, which is a list of initializers for
17889 either base class or a non-static data member. The TREE_PURPOSEs
17890 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17891 instantiate_decl. */
17894 tsubst_initializer_list (tree t, tree argvec)
17896 tree inits = NULL_TREE;
17898 for (; t; t = TREE_CHAIN (t))
17902 tree expanded_bases = NULL_TREE;
17903 tree expanded_arguments = NULL_TREE;
17906 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17911 /* Expand the base class expansion type into separate base
17913 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17914 tf_warning_or_error,
17916 if (expanded_bases == error_mark_node)
17919 /* We'll be building separate TREE_LISTs of arguments for
17921 len = TREE_VEC_LENGTH (expanded_bases);
17922 expanded_arguments = make_tree_vec (len);
17923 for (i = 0; i < len; i++)
17924 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17926 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17927 expand each argument in the TREE_VALUE of t. */
17928 expr = make_node (EXPR_PACK_EXPANSION);
17929 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17930 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17932 if (TREE_VALUE (t) == void_type_node)
17933 /* VOID_TYPE_NODE is used to indicate
17934 value-initialization. */
17936 for (i = 0; i < len; i++)
17937 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17941 /* Substitute parameter packs into each argument in the
17943 in_base_initializer = 1;
17944 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17946 tree expanded_exprs;
17948 /* Expand the argument. */
17949 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17951 = tsubst_pack_expansion (expr, argvec,
17952 tf_warning_or_error,
17954 if (expanded_exprs == error_mark_node)
17957 /* Prepend each of the expanded expressions to the
17958 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17959 for (i = 0; i < len; i++)
17961 TREE_VEC_ELT (expanded_arguments, i) =
17962 tree_cons (NULL_TREE,
17963 TREE_VEC_ELT (expanded_exprs, i),
17964 TREE_VEC_ELT (expanded_arguments, i));
17967 in_base_initializer = 0;
17969 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17970 since we built them backwards. */
17971 for (i = 0; i < len; i++)
17973 TREE_VEC_ELT (expanded_arguments, i) =
17974 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17979 for (i = 0; i < len; ++i)
17981 if (expanded_bases)
17983 decl = TREE_VEC_ELT (expanded_bases, i);
17984 decl = expand_member_init (decl);
17985 init = TREE_VEC_ELT (expanded_arguments, i);
17989 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17990 tf_warning_or_error, NULL_TREE);
17992 decl = expand_member_init (decl);
17993 if (decl && !DECL_P (decl))
17994 in_base_initializer = 1;
17996 init = TREE_VALUE (t);
17997 if (init != void_type_node)
17998 init = tsubst_expr (init, argvec,
17999 tf_warning_or_error, NULL_TREE,
18000 /*integral_constant_expression_p=*/false);
18001 in_base_initializer = 0;
18006 init = build_tree_list (decl, init);
18007 TREE_CHAIN (init) = inits;
18015 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18018 set_current_access_from_decl (tree decl)
18020 if (TREE_PRIVATE (decl))
18021 current_access_specifier = access_private_node;
18022 else if (TREE_PROTECTED (decl))
18023 current_access_specifier = access_protected_node;
18025 current_access_specifier = access_public_node;
18028 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18029 is the instantiation (which should have been created with
18030 start_enum) and ARGS are the template arguments to use. */
18033 tsubst_enum (tree tag, tree newtag, tree args)
18037 if (SCOPED_ENUM_P (newtag))
18038 begin_scope (sk_scoped_enum, newtag);
18040 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18045 decl = TREE_VALUE (e);
18046 /* Note that in a template enum, the TREE_VALUE is the
18047 CONST_DECL, not the corresponding INTEGER_CST. */
18048 value = tsubst_expr (DECL_INITIAL (decl),
18049 args, tf_warning_or_error, NULL_TREE,
18050 /*integral_constant_expression_p=*/true);
18052 /* Give this enumeration constant the correct access. */
18053 set_current_access_from_decl (decl);
18055 /* Actually build the enumerator itself. */
18057 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
18060 if (SCOPED_ENUM_P (newtag))
18063 finish_enum_value_list (newtag);
18064 finish_enum (newtag);
18066 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
18067 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
18070 /* DECL is a FUNCTION_DECL that is a template specialization. Return
18071 its type -- but without substituting the innermost set of template
18072 arguments. So, innermost set of template parameters will appear in
18076 get_mostly_instantiated_function_type (tree decl)
18084 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
18085 targs = DECL_TI_ARGS (decl);
18086 tparms = DECL_TEMPLATE_PARMS (tmpl);
18087 parm_depth = TMPL_PARMS_DEPTH (tparms);
18089 /* There should be as many levels of arguments as there are levels
18091 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18093 fn_type = TREE_TYPE (tmpl);
18095 if (parm_depth == 1)
18096 /* No substitution is necessary. */
18103 /* Replace the innermost level of the TARGS with NULL_TREEs to
18104 let tsubst know not to substitute for those parameters. */
18105 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18106 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18107 SET_TMPL_ARGS_LEVEL (partial_args, i,
18108 TMPL_ARGS_LEVEL (targs, i));
18109 SET_TMPL_ARGS_LEVEL (partial_args,
18110 TMPL_ARGS_DEPTH (targs),
18111 make_tree_vec (DECL_NTPARMS (tmpl)));
18113 /* Make sure that we can see identifiers, and compute access
18115 push_access_scope (decl);
18117 ++processing_template_decl;
18118 /* Now, do the (partial) substitution to figure out the
18119 appropriate function type. */
18120 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
18121 --processing_template_decl;
18123 /* Substitute into the template parameters to obtain the real
18124 innermost set of parameters. This step is important if the
18125 innermost set of template parameters contains value
18126 parameters whose types depend on outer template parameters. */
18127 TREE_VEC_LENGTH (partial_args)--;
18128 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
18130 pop_access_scope (decl);
18136 /* Return truthvalue if we're processing a template different from
18137 the last one involved in diagnostics. */
18139 problematic_instantiation_changed (void)
18141 return last_template_error_tick != tinst_level_tick;
18144 /* Remember current template involved in diagnostics. */
18146 record_last_problematic_instantiation (void)
18148 last_template_error_tick = tinst_level_tick;
18151 struct tinst_level *
18152 current_instantiation (void)
18154 return current_tinst_level;
18157 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18158 type. Return zero for ok, nonzero for disallowed. Issue error and
18159 warning messages under control of COMPLAIN. */
18162 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18164 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18166 else if (POINTER_TYPE_P (type))
18168 else if (TYPE_PTR_TO_MEMBER_P (type))
18170 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18172 else if (TREE_CODE (type) == TYPENAME_TYPE)
18174 else if (TREE_CODE (type) == DECLTYPE_TYPE)
18177 if (complain & tf_error)
18178 error ("%q#T is not a valid type for a template constant parameter", type);
18182 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18183 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18186 dependent_type_p_r (tree type)
18192 A type is dependent if it is:
18194 -- a template parameter. Template template parameters are types
18195 for us (since TYPE_P holds true for them) so we handle
18197 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18198 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18200 /* -- a qualified-id with a nested-name-specifier which contains a
18201 class-name that names a dependent type or whose unqualified-id
18202 names a dependent type. */
18203 if (TREE_CODE (type) == TYPENAME_TYPE)
18205 /* -- a cv-qualified type where the cv-unqualified type is
18207 type = TYPE_MAIN_VARIANT (type);
18208 /* -- a compound type constructed from any dependent type. */
18209 if (TYPE_PTR_TO_MEMBER_P (type))
18210 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18211 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18213 else if (TREE_CODE (type) == POINTER_TYPE
18214 || TREE_CODE (type) == REFERENCE_TYPE)
18215 return dependent_type_p (TREE_TYPE (type));
18216 else if (TREE_CODE (type) == FUNCTION_TYPE
18217 || TREE_CODE (type) == METHOD_TYPE)
18221 if (dependent_type_p (TREE_TYPE (type)))
18223 for (arg_type = TYPE_ARG_TYPES (type);
18225 arg_type = TREE_CHAIN (arg_type))
18226 if (dependent_type_p (TREE_VALUE (arg_type)))
18230 /* -- an array type constructed from any dependent type or whose
18231 size is specified by a constant expression that is
18234 We checked for type- and value-dependence of the bounds in
18235 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18236 if (TREE_CODE (type) == ARRAY_TYPE)
18238 if (TYPE_DOMAIN (type)
18239 && dependent_type_p (TYPE_DOMAIN (type)))
18241 return dependent_type_p (TREE_TYPE (type));
18244 /* -- a template-id in which either the template name is a template
18246 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18248 /* ... or any of the template arguments is a dependent type or
18249 an expression that is type-dependent or value-dependent. */
18250 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18251 && (any_dependent_template_arguments_p
18252 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18255 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18256 dependent; if the argument of the `typeof' expression is not
18257 type-dependent, then it should already been have resolved. */
18258 if (TREE_CODE (type) == TYPEOF_TYPE
18259 || TREE_CODE (type) == DECLTYPE_TYPE
18260 || TREE_CODE (type) == UNDERLYING_TYPE)
18263 /* A template argument pack is dependent if any of its packed
18265 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18267 tree args = ARGUMENT_PACK_ARGS (type);
18268 int i, len = TREE_VEC_LENGTH (args);
18269 for (i = 0; i < len; ++i)
18270 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18274 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18275 be template parameters. */
18276 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18279 /* The standard does not specifically mention types that are local
18280 to template functions or local classes, but they should be
18281 considered dependent too. For example:
18283 template <int I> void f() {
18288 The size of `E' cannot be known until the value of `I' has been
18289 determined. Therefore, `E' must be considered dependent. */
18290 scope = TYPE_CONTEXT (type);
18291 if (scope && TYPE_P (scope))
18292 return dependent_type_p (scope);
18293 /* Don't use type_dependent_expression_p here, as it can lead
18294 to infinite recursion trying to determine whether a lambda
18295 nested in a lambda is dependent (c++/47687). */
18296 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
18297 && DECL_LANG_SPECIFIC (scope)
18298 && DECL_TEMPLATE_INFO (scope)
18299 && (any_dependent_template_arguments_p
18300 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
18303 /* Other types are non-dependent. */
18307 /* Returns TRUE if TYPE is dependent, in the sense of
18308 [temp.dep.type]. Note that a NULL type is considered dependent. */
18311 dependent_type_p (tree type)
18313 /* If there are no template parameters in scope, then there can't be
18314 any dependent types. */
18315 if (!processing_template_decl)
18317 /* If we are not processing a template, then nobody should be
18318 providing us with a dependent type. */
18320 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18324 /* If the type is NULL, we have not computed a type for the entity
18325 in question; in that case, the type is dependent. */
18329 /* Erroneous types can be considered non-dependent. */
18330 if (type == error_mark_node)
18333 /* If we have not already computed the appropriate value for TYPE,
18335 if (!TYPE_DEPENDENT_P_VALID (type))
18337 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18338 TYPE_DEPENDENT_P_VALID (type) = 1;
18341 return TYPE_DEPENDENT_P (type);
18344 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18345 lookup. In other words, a dependent type that is not the current
18349 dependent_scope_p (tree scope)
18351 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18352 && !currently_open_class (scope));
18355 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18356 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18359 /* Note that this predicate is not appropriate for general expressions;
18360 only constant expressions (that satisfy potential_constant_expression)
18361 can be tested for value dependence.
18363 We should really also have a predicate for "instantiation-dependent".
18365 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18366 (what about instantiation-dependent constant-expressions?)
18367 is_late_template_attribute: defer if instantiation-dependent.
18368 compute_array_index_type: proceed if constant and not t- or v-dependent
18369 if instantiation-dependent, need to remember full expression
18370 uses_template_parms: FIXME - need to audit callers
18371 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18372 dependent_type_p [array_type]: dependent if index type is dependent
18374 static_assert - instantiation-dependent */
18377 value_dependent_expression_p (tree expression)
18379 if (!processing_template_decl)
18382 /* A name declared with a dependent type. */
18383 if (DECL_P (expression) && type_dependent_expression_p (expression))
18386 switch (TREE_CODE (expression))
18388 case IDENTIFIER_NODE:
18389 /* A name that has not been looked up -- must be dependent. */
18392 case TEMPLATE_PARM_INDEX:
18393 /* A non-type template parm. */
18397 /* A non-type template parm. */
18398 if (DECL_TEMPLATE_PARM_P (expression))
18400 return value_dependent_expression_p (DECL_INITIAL (expression));
18403 /* A constant with literal type and is initialized
18404 with an expression that is value-dependent. */
18405 if (DECL_INITIAL (expression)
18406 && decl_constant_var_p (expression)
18407 && value_dependent_expression_p (DECL_INITIAL (expression)))
18411 case DYNAMIC_CAST_EXPR:
18412 case STATIC_CAST_EXPR:
18413 case CONST_CAST_EXPR:
18414 case REINTERPRET_CAST_EXPR:
18416 /* These expressions are value-dependent if the type to which
18417 the cast occurs is dependent or the expression being casted
18418 is value-dependent. */
18420 tree type = TREE_TYPE (expression);
18422 if (dependent_type_p (type))
18425 /* A functional cast has a list of operands. */
18426 expression = TREE_OPERAND (expression, 0);
18429 /* If there are no operands, it must be an expression such
18430 as "int()". This should not happen for aggregate types
18431 because it would form non-constant expressions. */
18432 gcc_assert (cxx_dialect >= cxx0x
18433 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18438 if (TREE_CODE (expression) == TREE_LIST)
18439 return any_value_dependent_elements_p (expression);
18441 return value_dependent_expression_p (expression);
18447 /* A `sizeof' expression is value-dependent if the operand is
18448 type-dependent or is a pack expansion. */
18449 expression = TREE_OPERAND (expression, 0);
18450 if (PACK_EXPANSION_P (expression))
18452 else if (TYPE_P (expression))
18453 return dependent_type_p (expression);
18454 return type_dependent_expression_p (expression);
18456 case AT_ENCODE_EXPR:
18457 /* An 'encode' expression is value-dependent if the operand is
18459 expression = TREE_OPERAND (expression, 0);
18460 return dependent_type_p (expression);
18462 case NOEXCEPT_EXPR:
18463 expression = TREE_OPERAND (expression, 0);
18464 return type_dependent_expression_p (expression);
18468 tree name = TREE_OPERAND (expression, 1);
18469 return value_dependent_expression_p (name);
18472 case COMPONENT_REF:
18473 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18474 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18476 case NONTYPE_ARGUMENT_PACK:
18477 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18478 is value-dependent. */
18480 tree values = ARGUMENT_PACK_ARGS (expression);
18481 int i, len = TREE_VEC_LENGTH (values);
18483 for (i = 0; i < len; ++i)
18484 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
18492 tree type2 = TRAIT_EXPR_TYPE2 (expression);
18493 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
18494 || (type2 ? dependent_type_p (type2) : false));
18498 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18499 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
18502 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18503 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
18507 tree op = TREE_OPERAND (expression, 0);
18508 return (value_dependent_expression_p (op)
18509 || has_value_dependent_address (op));
18514 tree fn = get_callee_fndecl (expression);
18516 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
18518 nargs = call_expr_nargs (expression);
18519 for (i = 0; i < nargs; ++i)
18521 tree op = CALL_EXPR_ARG (expression, i);
18522 /* In a call to a constexpr member function, look through the
18523 implicit ADDR_EXPR on the object argument so that it doesn't
18524 cause the call to be considered value-dependent. We also
18525 look through it in potential_constant_expression. */
18526 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
18527 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
18528 && TREE_CODE (op) == ADDR_EXPR)
18529 op = TREE_OPERAND (op, 0);
18530 if (value_dependent_expression_p (op))
18536 case TEMPLATE_ID_EXPR:
18537 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
18539 return type_dependent_expression_p (expression);
18545 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
18546 if (value_dependent_expression_p (val))
18552 /* A constant expression is value-dependent if any subexpression is
18553 value-dependent. */
18554 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
18556 case tcc_reference:
18558 case tcc_comparison:
18560 case tcc_expression:
18563 int i, len = cp_tree_operand_length (expression);
18565 for (i = 0; i < len; i++)
18567 tree t = TREE_OPERAND (expression, i);
18569 /* In some cases, some of the operands may be missing.l
18570 (For example, in the case of PREDECREMENT_EXPR, the
18571 amount to increment by may be missing.) That doesn't
18572 make the expression dependent. */
18573 if (t && value_dependent_expression_p (t))
18584 /* The expression is not value-dependent. */
18588 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
18589 [temp.dep.expr]. Note that an expression with no type is
18590 considered dependent. Other parts of the compiler arrange for an
18591 expression with type-dependent subexpressions to have no type, so
18592 this function doesn't have to be fully recursive. */
18595 type_dependent_expression_p (tree expression)
18597 if (!processing_template_decl)
18600 if (expression == error_mark_node)
18603 /* An unresolved name is always dependent. */
18604 if (TREE_CODE (expression) == IDENTIFIER_NODE
18605 || TREE_CODE (expression) == USING_DECL)
18608 /* Some expression forms are never type-dependent. */
18609 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
18610 || TREE_CODE (expression) == SIZEOF_EXPR
18611 || TREE_CODE (expression) == ALIGNOF_EXPR
18612 || TREE_CODE (expression) == AT_ENCODE_EXPR
18613 || TREE_CODE (expression) == NOEXCEPT_EXPR
18614 || TREE_CODE (expression) == TRAIT_EXPR
18615 || TREE_CODE (expression) == TYPEID_EXPR
18616 || TREE_CODE (expression) == DELETE_EXPR
18617 || TREE_CODE (expression) == VEC_DELETE_EXPR
18618 || TREE_CODE (expression) == THROW_EXPR)
18621 /* The types of these expressions depends only on the type to which
18622 the cast occurs. */
18623 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
18624 || TREE_CODE (expression) == STATIC_CAST_EXPR
18625 || TREE_CODE (expression) == CONST_CAST_EXPR
18626 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
18627 || TREE_CODE (expression) == CAST_EXPR)
18628 return dependent_type_p (TREE_TYPE (expression));
18630 /* The types of these expressions depends only on the type created
18631 by the expression. */
18632 if (TREE_CODE (expression) == NEW_EXPR
18633 || TREE_CODE (expression) == VEC_NEW_EXPR)
18635 /* For NEW_EXPR tree nodes created inside a template, either
18636 the object type itself or a TREE_LIST may appear as the
18638 tree type = TREE_OPERAND (expression, 1);
18639 if (TREE_CODE (type) == TREE_LIST)
18640 /* This is an array type. We need to check array dimensions
18642 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
18643 || value_dependent_expression_p
18644 (TREE_OPERAND (TREE_VALUE (type), 1));
18646 return dependent_type_p (type);
18649 if (TREE_CODE (expression) == SCOPE_REF)
18651 tree scope = TREE_OPERAND (expression, 0);
18652 tree name = TREE_OPERAND (expression, 1);
18654 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
18655 contains an identifier associated by name lookup with one or more
18656 declarations declared with a dependent type, or...a
18657 nested-name-specifier or qualified-id that names a member of an
18658 unknown specialization. */
18659 return (type_dependent_expression_p (name)
18660 || dependent_scope_p (scope));
18663 if (TREE_CODE (expression) == FUNCTION_DECL
18664 && DECL_LANG_SPECIFIC (expression)
18665 && DECL_TEMPLATE_INFO (expression)
18666 && (any_dependent_template_arguments_p
18667 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
18670 if (TREE_CODE (expression) == TEMPLATE_DECL
18671 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
18674 if (TREE_CODE (expression) == STMT_EXPR)
18675 expression = stmt_expr_value_expr (expression);
18677 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
18682 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
18684 if (type_dependent_expression_p (elt))
18690 /* A static data member of the current instantiation with incomplete
18691 array type is type-dependent, as the definition and specializations
18692 can have different bounds. */
18693 if (TREE_CODE (expression) == VAR_DECL
18694 && DECL_CLASS_SCOPE_P (expression)
18695 && dependent_type_p (DECL_CONTEXT (expression))
18696 && VAR_HAD_UNKNOWN_BOUND (expression))
18699 if (TREE_TYPE (expression) == unknown_type_node)
18701 if (TREE_CODE (expression) == ADDR_EXPR)
18702 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
18703 if (TREE_CODE (expression) == COMPONENT_REF
18704 || TREE_CODE (expression) == OFFSET_REF)
18706 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
18708 expression = TREE_OPERAND (expression, 1);
18709 if (TREE_CODE (expression) == IDENTIFIER_NODE)
18712 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
18713 if (TREE_CODE (expression) == SCOPE_REF)
18716 if (TREE_CODE (expression) == BASELINK)
18717 expression = BASELINK_FUNCTIONS (expression);
18719 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
18721 if (any_dependent_template_arguments_p
18722 (TREE_OPERAND (expression, 1)))
18724 expression = TREE_OPERAND (expression, 0);
18726 gcc_assert (TREE_CODE (expression) == OVERLOAD
18727 || TREE_CODE (expression) == FUNCTION_DECL);
18731 if (type_dependent_expression_p (OVL_CURRENT (expression)))
18733 expression = OVL_NEXT (expression);
18738 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
18740 return (dependent_type_p (TREE_TYPE (expression)));
18743 /* Like type_dependent_expression_p, but it also works while not processing
18744 a template definition, i.e. during substitution or mangling. */
18747 type_dependent_expression_p_push (tree expr)
18750 ++processing_template_decl;
18751 b = type_dependent_expression_p (expr);
18752 --processing_template_decl;
18756 /* Returns TRUE if ARGS contains a type-dependent expression. */
18759 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
18764 FOR_EACH_VEC_ELT (tree, args, i, arg)
18766 if (type_dependent_expression_p (arg))
18772 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18773 expressions) contains any type-dependent expressions. */
18776 any_type_dependent_elements_p (const_tree list)
18778 for (; list; list = TREE_CHAIN (list))
18779 if (value_dependent_expression_p (TREE_VALUE (list)))
18785 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18786 expressions) contains any value-dependent expressions. */
18789 any_value_dependent_elements_p (const_tree list)
18791 for (; list; list = TREE_CHAIN (list))
18792 if (value_dependent_expression_p (TREE_VALUE (list)))
18798 /* Returns TRUE if the ARG (a template argument) is dependent. */
18801 dependent_template_arg_p (tree arg)
18803 if (!processing_template_decl)
18806 /* Assume a template argument that was wrongly written by the user
18807 is dependent. This is consistent with what
18808 any_dependent_template_arguments_p [that calls this function]
18810 if (arg == error_mark_node)
18813 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
18814 arg = ARGUMENT_PACK_SELECT_ARG (arg);
18816 if (TREE_CODE (arg) == TEMPLATE_DECL
18817 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18818 return dependent_template_p (arg);
18819 else if (ARGUMENT_PACK_P (arg))
18821 tree args = ARGUMENT_PACK_ARGS (arg);
18822 int i, len = TREE_VEC_LENGTH (args);
18823 for (i = 0; i < len; ++i)
18825 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18831 else if (TYPE_P (arg))
18832 return dependent_type_p (arg);
18834 return (type_dependent_expression_p (arg)
18835 || value_dependent_expression_p (arg));
18838 /* Returns true if ARGS (a collection of template arguments) contains
18839 any types that require structural equality testing. */
18842 any_template_arguments_need_structural_equality_p (tree args)
18849 if (args == error_mark_node)
18852 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18854 tree level = TMPL_ARGS_LEVEL (args, i + 1);
18855 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18857 tree arg = TREE_VEC_ELT (level, j);
18858 tree packed_args = NULL_TREE;
18861 if (ARGUMENT_PACK_P (arg))
18863 /* Look inside the argument pack. */
18864 packed_args = ARGUMENT_PACK_ARGS (arg);
18865 len = TREE_VEC_LENGTH (packed_args);
18868 for (k = 0; k < len; ++k)
18871 arg = TREE_VEC_ELT (packed_args, k);
18873 if (error_operand_p (arg))
18875 else if (TREE_CODE (arg) == TEMPLATE_DECL
18876 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18878 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18880 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18881 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18890 /* Returns true if ARGS (a collection of template arguments) contains
18891 any dependent arguments. */
18894 any_dependent_template_arguments_p (const_tree args)
18901 if (args == error_mark_node)
18904 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18906 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18907 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18908 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18915 /* Returns TRUE if the template TMPL is dependent. */
18918 dependent_template_p (tree tmpl)
18920 if (TREE_CODE (tmpl) == OVERLOAD)
18924 if (dependent_template_p (OVL_CURRENT (tmpl)))
18926 tmpl = OVL_NEXT (tmpl);
18931 /* Template template parameters are dependent. */
18932 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18933 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18935 /* So are names that have not been looked up. */
18936 if (TREE_CODE (tmpl) == SCOPE_REF
18937 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18939 /* So are member templates of dependent classes. */
18940 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18941 return dependent_type_p (DECL_CONTEXT (tmpl));
18945 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18948 dependent_template_id_p (tree tmpl, tree args)
18950 return (dependent_template_p (tmpl)
18951 || any_dependent_template_arguments_p (args));
18954 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18958 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18962 if (!processing_template_decl)
18965 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18967 tree decl = TREE_VEC_ELT (declv, i);
18968 tree init = TREE_VEC_ELT (initv, i);
18969 tree cond = TREE_VEC_ELT (condv, i);
18970 tree incr = TREE_VEC_ELT (incrv, i);
18972 if (type_dependent_expression_p (decl))
18975 if (init && type_dependent_expression_p (init))
18978 if (type_dependent_expression_p (cond))
18981 if (COMPARISON_CLASS_P (cond)
18982 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18983 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18986 if (TREE_CODE (incr) == MODOP_EXPR)
18988 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18989 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18992 else if (type_dependent_expression_p (incr))
18994 else if (TREE_CODE (incr) == MODIFY_EXPR)
18996 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18998 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19000 tree t = TREE_OPERAND (incr, 1);
19001 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19002 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19011 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19012 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19013 no such TYPE can be found. Note that this function peers inside
19014 uninstantiated templates and therefore should be used only in
19015 extremely limited situations. ONLY_CURRENT_P restricts this
19016 peering to the currently open classes hierarchy (which is required
19017 when comparing types). */
19020 resolve_typename_type (tree type, bool only_current_p)
19029 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19031 scope = TYPE_CONTEXT (type);
19032 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19033 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19034 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19035 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19036 identifier of the TYPENAME_TYPE anymore.
19037 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19038 TYPENAME_TYPE instead, we avoid messing up with a possible
19039 typedef variant case. */
19040 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
19042 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
19043 it first before we can figure out what NAME refers to. */
19044 if (TREE_CODE (scope) == TYPENAME_TYPE)
19045 scope = resolve_typename_type (scope, only_current_p);
19046 /* If we don't know what SCOPE refers to, then we cannot resolve the
19048 if (TREE_CODE (scope) == TYPENAME_TYPE)
19050 /* If the SCOPE is a template type parameter, we have no way of
19051 resolving the name. */
19052 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
19054 /* If the SCOPE is not the current instantiation, there's no reason
19055 to look inside it. */
19056 if (only_current_p && !currently_open_class (scope))
19058 /* If this is a typedef, we don't want to look inside (c++/11987). */
19059 if (typedef_variant_p (type))
19061 /* If SCOPE isn't the template itself, it will not have a valid
19062 TYPE_FIELDS list. */
19063 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
19064 /* scope is either the template itself or a compatible instantiation
19065 like X<T>, so look up the name in the original template. */
19066 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
19068 /* scope is a partial instantiation, so we can't do the lookup or we
19069 will lose the template arguments. */
19071 /* Enter the SCOPE so that name lookup will be resolved as if we
19072 were in the class definition. In particular, SCOPE will no
19073 longer be considered a dependent type. */
19074 pushed_scope = push_scope (scope);
19075 /* Look up the declaration. */
19076 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
19078 result = NULL_TREE;
19080 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
19081 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
19084 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
19085 && TREE_CODE (decl) == TYPE_DECL)
19087 result = TREE_TYPE (decl);
19088 if (result == error_mark_node)
19089 result = NULL_TREE;
19091 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19092 && DECL_CLASS_TEMPLATE_P (decl))
19096 /* Obtain the template and the arguments. */
19097 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19098 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19099 /* Instantiate the template. */
19100 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
19101 /*entering_scope=*/0,
19102 tf_error | tf_user);
19103 if (result == error_mark_node)
19104 result = NULL_TREE;
19107 /* Leave the SCOPE. */
19109 pop_scope (pushed_scope);
19111 /* If we failed to resolve it, return the original typename. */
19115 /* If lookup found a typename type, resolve that too. */
19116 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
19118 /* Ill-formed programs can cause infinite recursion here, so we
19119 must catch that. */
19120 TYPENAME_IS_RESOLVING_P (type) = 1;
19121 result = resolve_typename_type (result, only_current_p);
19122 TYPENAME_IS_RESOLVING_P (type) = 0;
19125 /* Qualify the resulting type. */
19126 quals = cp_type_quals (type);
19128 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
19133 /* EXPR is an expression which is not type-dependent. Return a proxy
19134 for EXPR that can be used to compute the types of larger
19135 expressions containing EXPR. */
19138 build_non_dependent_expr (tree expr)
19142 #ifdef ENABLE_CHECKING
19143 /* Try to get a constant value for all non-type-dependent expressions in
19144 order to expose bugs in *_dependent_expression_p and constexpr. */
19145 if (cxx_dialect >= cxx0x)
19146 maybe_constant_value (fold_non_dependent_expr (expr));
19149 /* Preserve OVERLOADs; the functions must be available to resolve
19152 if (TREE_CODE (inner_expr) == STMT_EXPR)
19153 inner_expr = stmt_expr_value_expr (inner_expr);
19154 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19155 inner_expr = TREE_OPERAND (inner_expr, 0);
19156 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19157 inner_expr = TREE_OPERAND (inner_expr, 1);
19158 if (is_overloaded_fn (inner_expr)
19159 || TREE_CODE (inner_expr) == OFFSET_REF)
19161 /* There is no need to return a proxy for a variable. */
19162 if (TREE_CODE (expr) == VAR_DECL)
19164 /* Preserve string constants; conversions from string constants to
19165 "char *" are allowed, even though normally a "const char *"
19166 cannot be used to initialize a "char *". */
19167 if (TREE_CODE (expr) == STRING_CST)
19169 /* Preserve arithmetic constants, as an optimization -- there is no
19170 reason to create a new node. */
19171 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19173 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19174 There is at least one place where we want to know that a
19175 particular expression is a throw-expression: when checking a ?:
19176 expression, there are special rules if the second or third
19177 argument is a throw-expression. */
19178 if (TREE_CODE (expr) == THROW_EXPR)
19181 if (TREE_CODE (expr) == COND_EXPR)
19182 return build3 (COND_EXPR,
19184 TREE_OPERAND (expr, 0),
19185 (TREE_OPERAND (expr, 1)
19186 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19187 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19188 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19189 if (TREE_CODE (expr) == COMPOUND_EXPR
19190 && !COMPOUND_EXPR_OVERLOADED (expr))
19191 return build2 (COMPOUND_EXPR,
19193 TREE_OPERAND (expr, 0),
19194 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19196 /* If the type is unknown, it can't really be non-dependent */
19197 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19199 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19200 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19203 /* ARGS is a vector of expressions as arguments to a function call.
19204 Replace the arguments with equivalent non-dependent expressions.
19205 This modifies ARGS in place. */
19208 make_args_non_dependent (VEC(tree,gc) *args)
19213 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19215 tree newarg = build_non_dependent_expr (arg);
19217 VEC_replace (tree, args, ix, newarg);
19221 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19222 with a level one deeper than the actual template parms. */
19227 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19228 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19229 TYPE_DECL, get_identifier ("auto"), au);
19230 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19231 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19232 (0, processing_template_decl + 1, processing_template_decl + 1,
19233 0, TYPE_NAME (au), NULL_TREE);
19234 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19235 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19236 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19241 /* Given type ARG, return std::initializer_list<ARG>. */
19246 tree std_init_list = namespace_binding
19247 (get_identifier ("initializer_list"), std_node);
19249 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19251 error ("deducing from brace-enclosed initializer list requires "
19252 "#include <initializer_list>");
19253 return error_mark_node;
19255 argvec = make_tree_vec (1);
19256 TREE_VEC_ELT (argvec, 0) = arg;
19257 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19258 NULL_TREE, 0, tf_warning_or_error);
19261 /* Replace auto in TYPE with std::initializer_list<auto>. */
19264 listify_autos (tree type, tree auto_node)
19266 tree init_auto = listify (auto_node);
19267 tree argvec = make_tree_vec (1);
19268 TREE_VEC_ELT (argvec, 0) = init_auto;
19269 if (processing_template_decl)
19270 argvec = add_to_template_args (current_template_args (), argvec);
19271 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19274 /* walk_tree helper for do_auto_deduction. */
19277 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19280 /* Is this a variable with the type we're looking for? */
19282 && TREE_TYPE (*tp) == type)
19288 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19289 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19292 do_auto_deduction (tree type, tree init, tree auto_node)
19294 tree parms, tparms, targs;
19299 /* The name of the object being declared shall not appear in the
19300 initializer expression. */
19301 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19304 error ("variable %q#D with %<auto%> type used in its own "
19305 "initializer", decl);
19306 return error_mark_node;
19309 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19310 with either a new invented type template parameter U or, if the
19311 initializer is a braced-init-list (8.5.4), with
19312 std::initializer_list<U>. */
19313 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19314 type = listify_autos (type, auto_node);
19316 init = resolve_nondeduced_context (init);
19318 parms = build_tree_list (NULL_TREE, type);
19320 tparms = make_tree_vec (1);
19321 targs = make_tree_vec (1);
19322 TREE_VEC_ELT (tparms, 0)
19323 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19324 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19325 DEDUCE_CALL, LOOKUP_NORMAL);
19328 if (type && type != error_mark_node)
19329 /* If type is error_mark_node a diagnostic must have been
19330 emitted by now. Also, having a mention to '<type error>'
19331 in the diagnostic is not really useful to the user. */
19332 error ("unable to deduce %qT from %qE", type, init);
19333 return error_mark_node;
19336 /* If the list of declarators contains more than one declarator, the type
19337 of each declared variable is determined as described above. If the
19338 type deduced for the template parameter U is not the same in each
19339 deduction, the program is ill-formed. */
19340 if (TREE_TYPE (auto_node)
19341 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19343 error ("inconsistent deduction for %qT: %qT and then %qT",
19344 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19345 return error_mark_node;
19347 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19349 if (processing_template_decl)
19350 targs = add_to_template_args (current_template_args (), targs);
19351 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19354 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19358 splice_late_return_type (tree type, tree late_return_type)
19362 if (late_return_type == NULL_TREE)
19364 argvec = make_tree_vec (1);
19365 TREE_VEC_ELT (argvec, 0) = late_return_type;
19366 if (processing_template_parmlist)
19367 /* For a late-specified return type in a template type-parameter, we
19368 need to add a dummy argument level for its parmlist. */
19369 argvec = add_to_template_args
19370 (make_tree_vec (processing_template_parmlist), argvec);
19371 if (current_template_parms)
19372 argvec = add_to_template_args (current_template_args (), argvec);
19373 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19376 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19379 is_auto (const_tree type)
19381 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19382 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
19388 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
19389 appear as a type-specifier for the declaration in question, we don't
19390 have to look through the whole type. */
19393 type_uses_auto (tree type)
19395 enum tree_code code;
19396 if (is_auto (type))
19399 code = TREE_CODE (type);
19401 if (code == POINTER_TYPE || code == REFERENCE_TYPE
19402 || code == OFFSET_TYPE || code == FUNCTION_TYPE
19403 || code == METHOD_TYPE || code == ARRAY_TYPE)
19404 return type_uses_auto (TREE_TYPE (type));
19406 if (TYPE_PTRMEMFUNC_P (type))
19407 return type_uses_auto (TREE_TYPE (TREE_TYPE
19408 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
19413 /* For a given template T, return the vector of typedefs referenced
19414 in T for which access check is needed at T instantiation time.
19415 T is either a FUNCTION_DECL or a RECORD_TYPE.
19416 Those typedefs were added to T by the function
19417 append_type_to_template_for_access_check. */
19419 VEC(qualified_typedef_usage_t,gc)*
19420 get_types_needing_access_check (tree t)
19423 VEC(qualified_typedef_usage_t,gc) *result = NULL;
19425 if (!t || t == error_mark_node)
19428 if (!(ti = get_template_info (t)))
19431 if (CLASS_TYPE_P (t)
19432 || TREE_CODE (t) == FUNCTION_DECL)
19434 if (!TI_TEMPLATE (ti))
19437 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19443 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19444 tied to T. That list of typedefs will be access checked at
19445 T instantiation time.
19446 T is either a FUNCTION_DECL or a RECORD_TYPE.
19447 TYPE_DECL is a TYPE_DECL node representing a typedef.
19448 SCOPE is the scope through which TYPE_DECL is accessed.
19449 LOCATION is the location of the usage point of TYPE_DECL.
19451 This function is a subroutine of
19452 append_type_to_template_for_access_check. */
19455 append_type_to_template_for_access_check_1 (tree t,
19458 location_t location)
19460 qualified_typedef_usage_t typedef_usage;
19463 if (!t || t == error_mark_node)
19466 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19467 || CLASS_TYPE_P (t))
19469 && TREE_CODE (type_decl) == TYPE_DECL
19472 if (!(ti = get_template_info (t)))
19475 gcc_assert (TI_TEMPLATE (ti));
19477 typedef_usage.typedef_decl = type_decl;
19478 typedef_usage.context = scope;
19479 typedef_usage.locus = location;
19481 VEC_safe_push (qualified_typedef_usage_t, gc,
19482 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
19486 /* Append TYPE_DECL to the template TEMPL.
19487 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
19488 At TEMPL instanciation time, TYPE_DECL will be checked to see
19489 if it can be accessed through SCOPE.
19490 LOCATION is the location of the usage point of TYPE_DECL.
19492 e.g. consider the following code snippet:
19499 template<class U> struct S
19501 C::myint mi; // <-- usage point of the typedef C::myint
19506 At S<char> instantiation time, we need to check the access of C::myint
19507 In other words, we need to check the access of the myint typedef through
19508 the C scope. For that purpose, this function will add the myint typedef
19509 and the scope C through which its being accessed to a list of typedefs
19510 tied to the template S. That list will be walked at template instantiation
19511 time and access check performed on each typedefs it contains.
19512 Note that this particular code snippet should yield an error because
19513 myint is private to C. */
19516 append_type_to_template_for_access_check (tree templ,
19519 location_t location)
19521 qualified_typedef_usage_t *iter;
19524 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
19526 /* Make sure we don't append the type to the template twice. */
19527 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
19528 get_types_needing_access_check (templ),
19530 if (iter->typedef_decl == type_decl && scope == iter->context)
19533 append_type_to_template_for_access_check_1 (templ, type_decl,
19537 /* Set up the hash tables for template instantiations. */
19540 init_template_processing (void)
19542 decl_specializations = htab_create_ggc (37,
19543 hash_specialization,
19544 eq_specializations,
19546 type_specializations = htab_create_ggc (37,
19547 hash_specialization,
19548 eq_specializations,
19552 /* Print stats about the template hash tables for -fstats. */
19555 print_template_statistics (void)
19557 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
19558 "%f collisions\n", (long) htab_size (decl_specializations),
19559 (long) htab_elements (decl_specializations),
19560 htab_collisions (decl_specializations));
19561 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
19562 "%f collisions\n", (long) htab_size (type_specializations),
19563 (long) htab_elements (type_specializations),
19564 htab_collisions (type_specializations));
19565 if (current_deduction_htab)
19566 fprintf (stderr, "current_deduction_htab: size %ld, %ld elements, "
19567 "%f collisions\n", (long) htab_size (current_deduction_htab),
19568 (long) htab_elements (current_deduction_htab),
19569 htab_collisions (current_deduction_htab));
19572 #include "gt-cp-pt.h"