1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 static void push_access_scope (tree);
113 static void pop_access_scope (tree);
114 static void push_deduction_access_scope (tree);
115 static void pop_deduction_access_scope (tree);
116 static bool resolve_overloaded_unification (tree, tree, tree, tree,
117 unification_kind_t, int);
118 static int try_one_overload (tree, tree, tree, tree, tree,
119 unification_kind_t, int, bool);
120 static int unify (tree, tree, tree, tree, int);
121 static void add_pending_template (tree);
122 static tree reopen_tinst_level (struct tinst_level *);
123 static tree tsubst_initializer_list (tree, tree);
124 static tree get_class_bindings (tree, tree, tree);
125 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
127 static void tsubst_enum (tree, tree, tree);
128 static tree add_to_template_args (tree, tree);
129 static tree add_outermost_template_args (tree, tree);
130 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
131 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
133 static int type_unification_real (tree, tree, tree, const tree *,
134 unsigned int, int, unification_kind_t, int);
135 static void note_template_header (int);
136 static tree convert_nontype_argument_function (tree, tree);
137 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
138 static tree convert_template_argument (tree, tree, tree,
139 tsubst_flags_t, int, tree);
140 static int for_each_template_parm (tree, tree_fn_t, void*,
141 struct pointer_set_t*, bool);
142 static tree expand_template_argument_pack (tree);
143 static tree build_template_parm_index (int, int, int, int, tree, tree);
144 static bool inline_needs_template_parms (tree);
145 static void push_inline_template_parms_recursive (tree, int);
146 static tree retrieve_local_specialization (tree);
147 static void register_local_specialization (tree, tree);
148 static hashval_t hash_specialization (const void *p);
149 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
150 static int mark_template_parm (tree, void *);
151 static int template_parm_this_level_p (tree, void *);
152 static tree tsubst_friend_function (tree, tree);
153 static tree tsubst_friend_class (tree, tree);
154 static int can_complete_type_without_circularity (tree);
155 static tree get_bindings (tree, tree, tree, bool);
156 static int template_decl_level (tree);
157 static int check_cv_quals_for_unify (int, tree, tree);
158 static void template_parm_level_and_index (tree, int*, int*);
159 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
160 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
161 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
163 static void regenerate_decl_from_template (tree, tree);
164 static tree most_specialized_class (tree, tree, tsubst_flags_t);
165 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
166 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
167 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
168 static bool check_specialization_scope (void);
169 static tree process_partial_specialization (tree);
170 static void set_current_access_from_decl (tree);
171 static tree get_template_base (tree, tree, tree, tree);
172 static tree try_class_unification (tree, tree, tree, tree);
173 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
175 static bool template_template_parm_bindings_ok_p (tree, tree);
176 static int template_args_equal (tree, tree);
177 static void tsubst_default_arguments (tree);
178 static tree for_each_template_parm_r (tree *, int *, void *);
179 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
180 static void copy_default_args_to_explicit_spec (tree);
181 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
182 static int eq_local_specializations (const void *, const void *);
183 static bool dependent_template_arg_p (tree);
184 static bool any_template_arguments_need_structural_equality_p (tree);
185 static bool dependent_type_p_r (tree);
186 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
187 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
188 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_decl (tree, tree, tsubst_flags_t);
190 static void perform_typedefs_access_check (tree tmpl, tree targs);
191 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
193 static tree listify (tree);
194 static tree listify_autos (tree, tree);
195 static tree template_parm_to_arg (tree t);
196 static tree current_template_args (void);
197 static tree fixup_template_type_parm_type (tree, int);
198 static tree fixup_template_parm_index (tree, tree, int);
199 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
201 /* Make the current scope suitable for access checking when we are
202 processing T. T can be FUNCTION_DECL for instantiated function
203 template, or VAR_DECL for static member variable (need by
204 instantiate_decl). */
207 push_access_scope (tree t)
209 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
210 || TREE_CODE (t) == VAR_DECL);
212 if (DECL_FRIEND_CONTEXT (t))
213 push_nested_class (DECL_FRIEND_CONTEXT (t));
214 else if (DECL_CLASS_SCOPE_P (t))
215 push_nested_class (DECL_CONTEXT (t));
217 pushclass (NULL_TREE);
219 if (TREE_CODE (t) == FUNCTION_DECL)
221 saved_access_scope = tree_cons
222 (NULL_TREE, current_function_decl, saved_access_scope);
223 current_function_decl = t;
227 /* Restore the scope set up by push_access_scope. T is the node we
231 pop_access_scope (tree t)
233 if (TREE_CODE (t) == FUNCTION_DECL)
235 current_function_decl = TREE_VALUE (saved_access_scope);
236 saved_access_scope = TREE_CHAIN (saved_access_scope);
239 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
245 /* Do any processing required when DECL (a member template
246 declaration) is finished. Returns the TEMPLATE_DECL corresponding
247 to DECL, unless it is a specialization, in which case the DECL
248 itself is returned. */
251 finish_member_template_decl (tree decl)
253 if (decl == error_mark_node)
254 return error_mark_node;
256 gcc_assert (DECL_P (decl));
258 if (TREE_CODE (decl) == TYPE_DECL)
262 type = TREE_TYPE (decl);
263 if (type == error_mark_node)
264 return error_mark_node;
265 if (MAYBE_CLASS_TYPE_P (type)
266 && CLASSTYPE_TEMPLATE_INFO (type)
267 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
269 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
270 check_member_template (tmpl);
275 else if (TREE_CODE (decl) == FIELD_DECL)
276 error ("data member %qD cannot be a member template", decl);
277 else if (DECL_TEMPLATE_INFO (decl))
279 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
281 check_member_template (DECL_TI_TEMPLATE (decl));
282 return DECL_TI_TEMPLATE (decl);
288 error ("invalid member template declaration %qD", decl);
290 return error_mark_node;
293 /* Create a template info node. */
296 build_template_info (tree template_decl, tree template_args)
298 tree result = make_node (TEMPLATE_INFO);
299 TI_TEMPLATE (result) = template_decl;
300 TI_ARGS (result) = template_args;
304 /* Return the template info node corresponding to T, whatever T is. */
307 get_template_info (const_tree t)
309 tree tinfo = NULL_TREE;
311 if (!t || t == error_mark_node)
314 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
315 tinfo = DECL_TEMPLATE_INFO (t);
317 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
320 if (TAGGED_TYPE_P (t))
321 tinfo = TYPE_TEMPLATE_INFO (t);
322 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
323 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
328 /* Returns the template nesting level of the indicated class TYPE.
338 A<T>::B<U> has depth two, while A<T> has depth one.
339 Both A<T>::B<int> and A<int>::B<U> have depth one, if
340 they are instantiations, not specializations.
342 This function is guaranteed to return 0 if passed NULL_TREE so
343 that, for example, `template_class_depth (current_class_type)' is
347 template_class_depth (tree type)
352 type && TREE_CODE (type) != NAMESPACE_DECL;
353 type = (TREE_CODE (type) == FUNCTION_DECL)
354 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
356 tree tinfo = get_template_info (type);
358 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
359 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
366 /* Subroutine of maybe_begin_member_template_processing.
367 Returns true if processing DECL needs us to push template parms. */
370 inline_needs_template_parms (tree decl)
372 if (! DECL_TEMPLATE_INFO (decl))
375 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
376 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
379 /* Subroutine of maybe_begin_member_template_processing.
380 Push the template parms in PARMS, starting from LEVELS steps into the
381 chain, and ending at the beginning, since template parms are listed
385 push_inline_template_parms_recursive (tree parmlist, int levels)
387 tree parms = TREE_VALUE (parmlist);
391 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
393 ++processing_template_decl;
394 current_template_parms
395 = tree_cons (size_int (processing_template_decl),
396 parms, current_template_parms);
397 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
399 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
401 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
403 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
405 if (parm == error_mark_node)
408 gcc_assert (DECL_P (parm));
410 switch (TREE_CODE (parm))
419 /* Make a CONST_DECL as is done in process_template_parm.
420 It is ugly that we recreate this here; the original
421 version built in process_template_parm is no longer
423 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
424 CONST_DECL, DECL_NAME (parm),
426 DECL_ARTIFICIAL (decl) = 1;
427 TREE_CONSTANT (decl) = 1;
428 TREE_READONLY (decl) = 1;
429 DECL_INITIAL (decl) = DECL_INITIAL (parm);
430 SET_DECL_TEMPLATE_PARM_P (decl);
441 /* Restore the template parameter context for a member template or
442 a friend template defined in a class definition. */
445 maybe_begin_member_template_processing (tree decl)
450 if (inline_needs_template_parms (decl))
452 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
453 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
455 if (DECL_TEMPLATE_SPECIALIZATION (decl))
458 parms = TREE_CHAIN (parms);
461 push_inline_template_parms_recursive (parms, levels);
464 /* Remember how many levels of template parameters we pushed so that
465 we can pop them later. */
466 VEC_safe_push (int, heap, inline_parm_levels, levels);
469 /* Undo the effects of maybe_begin_member_template_processing. */
472 maybe_end_member_template_processing (void)
477 if (VEC_length (int, inline_parm_levels) == 0)
480 last = VEC_pop (int, inline_parm_levels);
481 for (i = 0; i < last; ++i)
483 --processing_template_decl;
484 current_template_parms = TREE_CHAIN (current_template_parms);
489 /* Return a new template argument vector which contains all of ARGS,
490 but has as its innermost set of arguments the EXTRA_ARGS. */
493 add_to_template_args (tree args, tree extra_args)
500 if (args == NULL_TREE || extra_args == error_mark_node)
503 extra_depth = TMPL_ARGS_DEPTH (extra_args);
504 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
506 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
507 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
509 for (j = 1; j <= extra_depth; ++j, ++i)
510 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
515 /* Like add_to_template_args, but only the outermost ARGS are added to
516 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
517 (EXTRA_ARGS) levels are added. This function is used to combine
518 the template arguments from a partial instantiation with the
519 template arguments used to attain the full instantiation from the
520 partial instantiation. */
523 add_outermost_template_args (tree args, tree extra_args)
527 /* If there are more levels of EXTRA_ARGS than there are ARGS,
528 something very fishy is going on. */
529 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
531 /* If *all* the new arguments will be the EXTRA_ARGS, just return
533 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
536 /* For the moment, we make ARGS look like it contains fewer levels. */
537 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
539 new_args = add_to_template_args (args, extra_args);
541 /* Now, we restore ARGS to its full dimensions. */
542 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
547 /* Return the N levels of innermost template arguments from the ARGS. */
550 get_innermost_template_args (tree args, int n)
558 /* If N is 1, just return the innermost set of template arguments. */
560 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
562 /* If we're not removing anything, just return the arguments we were
564 extra_levels = TMPL_ARGS_DEPTH (args) - n;
565 gcc_assert (extra_levels >= 0);
566 if (extra_levels == 0)
569 /* Make a new set of arguments, not containing the outer arguments. */
570 new_args = make_tree_vec (n);
571 for (i = 1; i <= n; ++i)
572 SET_TMPL_ARGS_LEVEL (new_args, i,
573 TMPL_ARGS_LEVEL (args, i + extra_levels));
578 /* The inverse of get_innermost_template_args: Return all but the innermost
579 EXTRA_LEVELS levels of template arguments from the ARGS. */
582 strip_innermost_template_args (tree args, int extra_levels)
585 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
590 /* If N is 1, just return the outermost set of template arguments. */
592 return TMPL_ARGS_LEVEL (args, 1);
594 /* If we're not removing anything, just return the arguments we were
596 gcc_assert (extra_levels >= 0);
597 if (extra_levels == 0)
600 /* Make a new set of arguments, not containing the inner arguments. */
601 new_args = make_tree_vec (n);
602 for (i = 1; i <= n; ++i)
603 SET_TMPL_ARGS_LEVEL (new_args, i,
604 TMPL_ARGS_LEVEL (args, i));
609 /* We've got a template header coming up; push to a new level for storing
613 begin_template_parm_list (void)
615 /* We use a non-tag-transparent scope here, which causes pushtag to
616 put tags in this scope, rather than in the enclosing class or
617 namespace scope. This is the right thing, since we want
618 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
619 global template class, push_template_decl handles putting the
620 TEMPLATE_DECL into top-level scope. For a nested template class,
623 template <class T> struct S1 {
624 template <class T> struct S2 {};
627 pushtag contains special code to call pushdecl_with_scope on the
628 TEMPLATE_DECL for S2. */
629 begin_scope (sk_template_parms, NULL);
630 ++processing_template_decl;
631 ++processing_template_parmlist;
632 note_template_header (0);
635 /* This routine is called when a specialization is declared. If it is
636 invalid to declare a specialization here, an error is reported and
637 false is returned, otherwise this routine will return true. */
640 check_specialization_scope (void)
642 tree scope = current_scope ();
646 An explicit specialization shall be declared in the namespace of
647 which the template is a member, or, for member templates, in the
648 namespace of which the enclosing class or enclosing class
649 template is a member. An explicit specialization of a member
650 function, member class or static data member of a class template
651 shall be declared in the namespace of which the class template
653 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
655 error ("explicit specialization in non-namespace scope %qD", scope);
661 In an explicit specialization declaration for a member of a class
662 template or a member template that appears in namespace scope,
663 the member template and some of its enclosing class templates may
664 remain unspecialized, except that the declaration shall not
665 explicitly specialize a class member template if its enclosing
666 class templates are not explicitly specialized as well. */
667 if (current_template_parms)
669 error ("enclosing class templates are not explicitly specialized");
676 /* We've just seen template <>. */
679 begin_specialization (void)
681 begin_scope (sk_template_spec, NULL);
682 note_template_header (1);
683 return check_specialization_scope ();
686 /* Called at then end of processing a declaration preceded by
690 end_specialization (void)
693 reset_specialization ();
696 /* Any template <>'s that we have seen thus far are not referring to a
697 function specialization. */
700 reset_specialization (void)
702 processing_specialization = 0;
703 template_header_count = 0;
706 /* We've just seen a template header. If SPECIALIZATION is nonzero,
707 it was of the form template <>. */
710 note_template_header (int specialization)
712 processing_specialization = specialization;
713 template_header_count++;
716 /* We're beginning an explicit instantiation. */
719 begin_explicit_instantiation (void)
721 gcc_assert (!processing_explicit_instantiation);
722 processing_explicit_instantiation = true;
727 end_explicit_instantiation (void)
729 gcc_assert (processing_explicit_instantiation);
730 processing_explicit_instantiation = false;
733 /* An explicit specialization or partial specialization TMPL is being
734 declared. Check that the namespace in which the specialization is
735 occurring is permissible. Returns false iff it is invalid to
736 specialize TMPL in the current namespace. */
739 check_specialization_namespace (tree tmpl)
741 tree tpl_ns = decl_namespace_context (tmpl);
745 An explicit specialization shall be declared in the namespace of
746 which the template is a member, or, for member templates, in the
747 namespace of which the enclosing class or enclosing class
748 template is a member. An explicit specialization of a member
749 function, member class or static data member of a class template
750 shall be declared in the namespace of which the class template is
752 if (current_scope() != DECL_CONTEXT (tmpl)
753 && !at_namespace_scope_p ())
755 error ("specialization of %qD must appear at namespace scope", tmpl);
758 if (is_associated_namespace (current_namespace, tpl_ns))
759 /* Same or super-using namespace. */
763 permerror (input_location, "specialization of %qD in different namespace", tmpl);
764 permerror (input_location, " from definition of %q+#D", tmpl);
769 /* SPEC is an explicit instantiation. Check that it is valid to
770 perform this explicit instantiation in the current namespace. */
773 check_explicit_instantiation_namespace (tree spec)
777 /* DR 275: An explicit instantiation shall appear in an enclosing
778 namespace of its template. */
779 ns = decl_namespace_context (spec);
780 if (!is_ancestor (current_namespace, ns))
781 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
782 "(which does not enclose namespace %qD)",
783 spec, current_namespace, ns);
786 /* The TYPE is being declared. If it is a template type, that means it
787 is a partial specialization. Do appropriate error-checking. */
790 maybe_process_partial_specialization (tree type)
794 if (type == error_mark_node)
795 return error_mark_node;
797 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
799 error ("name of class shadows template template parameter %qD",
801 return error_mark_node;
804 context = TYPE_CONTEXT (type);
806 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
808 /* This is for ordinary explicit specialization and partial
809 specialization of a template class such as:
811 template <> class C<int>;
815 template <class T> class C<T*>;
817 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
819 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
820 && !COMPLETE_TYPE_P (type))
822 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
823 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
824 if (processing_template_decl)
826 if (push_template_decl (TYPE_MAIN_DECL (type))
828 return error_mark_node;
831 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
832 error ("specialization of %qT after instantiation", type);
834 else if (CLASS_TYPE_P (type)
835 && !CLASSTYPE_USE_TEMPLATE (type)
836 && CLASSTYPE_TEMPLATE_INFO (type)
837 && context && CLASS_TYPE_P (context)
838 && CLASSTYPE_TEMPLATE_INFO (context))
840 /* This is for an explicit specialization of member class
841 template according to [temp.expl.spec/18]:
843 template <> template <class U> class C<int>::D;
845 The context `C<int>' must be an implicit instantiation.
846 Otherwise this is just a member class template declared
849 template <> class C<int> { template <class U> class D; };
850 template <> template <class U> class C<int>::D;
852 In the first case, `C<int>::D' is a specialization of `C<T>::D'
853 while in the second case, `C<int>::D' is a primary template
854 and `C<T>::D' may not exist. */
856 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
857 && !COMPLETE_TYPE_P (type))
860 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
862 if (current_namespace
863 != decl_namespace_context (tmpl))
865 permerror (input_location, "specializing %q#T in different namespace", type);
866 permerror (input_location, " from definition of %q+#D", tmpl);
869 /* Check for invalid specialization after instantiation:
871 template <> template <> class C<int>::D<int>;
872 template <> template <class U> class C<int>::D; */
874 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
875 t; t = TREE_CHAIN (t))
877 tree inst = TREE_VALUE (t);
878 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
880 /* We already have a full specialization of this partial
881 instantiation. Reassign it to the new member
882 specialization template. */
886 elt.tmpl = most_general_template (tmpl);
887 elt.args = CLASSTYPE_TI_ARGS (inst);
890 htab_remove_elt (type_specializations, &elt);
893 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
895 slot = (spec_entry **)
896 htab_find_slot (type_specializations, &elt, INSERT);
897 *slot = ggc_alloc_spec_entry ();
900 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
901 /* But if we've had an implicit instantiation, that's a
902 problem ([temp.expl.spec]/6). */
903 error ("specialization %qT after instantiation %qT",
907 /* Mark TYPE as a specialization. And as a result, we only
908 have one level of template argument for the innermost
910 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
911 CLASSTYPE_TI_ARGS (type)
912 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
915 else if (processing_specialization)
917 /* Someday C++0x may allow for enum template specialization. */
918 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
919 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
920 pedwarn (input_location, OPT_pedantic, "template specialization "
921 "of %qD not allowed by ISO C++", type);
924 error ("explicit specialization of non-template %qT", type);
925 return error_mark_node;
932 /* Returns nonzero if we can optimize the retrieval of specializations
933 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
934 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
937 optimize_specialization_lookup_p (tree tmpl)
939 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
940 && DECL_CLASS_SCOPE_P (tmpl)
941 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
943 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
944 /* The optimized lookup depends on the fact that the
945 template arguments for the member function template apply
946 purely to the containing class, which is not true if the
947 containing class is an explicit or partial
949 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
950 && !DECL_MEMBER_TEMPLATE_P (tmpl)
951 && !DECL_CONV_FN_P (tmpl)
952 /* It is possible to have a template that is not a member
953 template and is not a member of a template class:
955 template <typename T>
956 struct S { friend A::f(); };
958 Here, the friend function is a template, but the context does
959 not have template information. The optimized lookup relies
960 on having ARGS be the template arguments for both the class
961 and the function template. */
962 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
965 /* Retrieve the specialization (in the sense of [temp.spec] - a
966 specialization is either an instantiation or an explicit
967 specialization) of TMPL for the given template ARGS. If there is
968 no such specialization, return NULL_TREE. The ARGS are a vector of
969 arguments, or a vector of vectors of arguments, in the case of
970 templates with more than one level of parameters.
972 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
973 then we search for a partial specialization matching ARGS. This
974 parameter is ignored if TMPL is not a class template. */
977 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
979 if (args == error_mark_node)
982 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
984 /* There should be as many levels of arguments as there are
985 levels of parameters. */
986 gcc_assert (TMPL_ARGS_DEPTH (args)
987 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
989 if (optimize_specialization_lookup_p (tmpl))
992 tree class_specialization;
993 VEC(tree,gc) *methods;
997 /* The template arguments actually apply to the containing
998 class. Find the class specialization with those
1000 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1001 class_specialization
1002 = retrieve_specialization (class_template, args, 0);
1003 if (!class_specialization)
1005 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1006 for the specialization. */
1007 idx = class_method_index_for_fn (class_specialization, tmpl);
1010 /* Iterate through the methods with the indicated name, looking
1011 for the one that has an instance of TMPL. */
1012 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1013 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1015 tree fn = OVL_CURRENT (fns);
1016 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1017 /* using-declarations can add base methods to the method vec,
1018 and we don't want those here. */
1019 && DECL_CONTEXT (fn) == class_specialization)
1028 htab_t specializations;
1032 elt.spec = NULL_TREE;
1034 if (DECL_CLASS_TEMPLATE_P (tmpl))
1035 specializations = type_specializations;
1037 specializations = decl_specializations;
1040 hash = hash_specialization (&elt);
1041 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1049 /* Like retrieve_specialization, but for local declarations. */
1052 retrieve_local_specialization (tree tmpl)
1056 if (local_specializations == NULL)
1059 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1060 htab_hash_pointer (tmpl));
1061 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1064 /* Returns nonzero iff DECL is a specialization of TMPL. */
1067 is_specialization_of (tree decl, tree tmpl)
1071 if (TREE_CODE (decl) == FUNCTION_DECL)
1075 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1081 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1083 for (t = TREE_TYPE (decl);
1085 t = CLASSTYPE_USE_TEMPLATE (t)
1086 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1087 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1094 /* Returns nonzero iff DECL is a specialization of friend declaration
1095 FRIEND_DECL according to [temp.friend]. */
1098 is_specialization_of_friend (tree decl, tree friend_decl)
1100 bool need_template = true;
1103 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1104 || TREE_CODE (decl) == TYPE_DECL);
1106 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1107 of a template class, we want to check if DECL is a specialization
1109 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1110 && DECL_TEMPLATE_INFO (friend_decl)
1111 && !DECL_USE_TEMPLATE (friend_decl))
1113 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1114 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1115 need_template = false;
1117 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1118 && !PRIMARY_TEMPLATE_P (friend_decl))
1119 need_template = false;
1121 /* There is nothing to do if this is not a template friend. */
1122 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1125 if (is_specialization_of (decl, friend_decl))
1129 A member of a class template may be declared to be a friend of a
1130 non-template class. In this case, the corresponding member of
1131 every specialization of the class template is a friend of the
1132 class granting friendship.
1134 For example, given a template friend declaration
1136 template <class T> friend void A<T>::f();
1138 the member function below is considered a friend
1140 template <> struct A<int> {
1144 For this type of template friend, TEMPLATE_DEPTH below will be
1145 nonzero. To determine if DECL is a friend of FRIEND, we first
1146 check if the enclosing class is a specialization of another. */
1148 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1150 && DECL_CLASS_SCOPE_P (decl)
1151 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1152 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1154 /* Next, we check the members themselves. In order to handle
1155 a few tricky cases, such as when FRIEND_DECL's are
1157 template <class T> friend void A<T>::g(T t);
1158 template <class T> template <T t> friend void A<T>::h();
1162 void A<int>::g(int);
1163 template <int> void A<int>::h();
1165 we need to figure out ARGS, the template arguments from
1166 the context of DECL. This is required for template substitution
1167 of `T' in the function parameter of `g' and template parameter
1168 of `h' in the above examples. Here ARGS corresponds to `int'. */
1170 tree context = DECL_CONTEXT (decl);
1171 tree args = NULL_TREE;
1172 int current_depth = 0;
1174 while (current_depth < template_depth)
1176 if (CLASSTYPE_TEMPLATE_INFO (context))
1178 if (current_depth == 0)
1179 args = TYPE_TI_ARGS (context);
1181 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1184 context = TYPE_CONTEXT (context);
1187 if (TREE_CODE (decl) == FUNCTION_DECL)
1192 tree friend_args_type;
1193 tree decl_args_type;
1195 /* Make sure that both DECL and FRIEND_DECL are templates or
1197 is_template = DECL_TEMPLATE_INFO (decl)
1198 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1199 if (need_template ^ is_template)
1201 else if (is_template)
1203 /* If both are templates, check template parameter list. */
1205 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1207 if (!comp_template_parms
1208 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1212 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1215 decl_type = TREE_TYPE (decl);
1217 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1218 tf_none, NULL_TREE);
1219 if (friend_type == error_mark_node)
1222 /* Check if return types match. */
1223 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1226 /* Check if function parameter types match, ignoring the
1227 `this' parameter. */
1228 friend_args_type = TYPE_ARG_TYPES (friend_type);
1229 decl_args_type = TYPE_ARG_TYPES (decl_type);
1230 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1231 friend_args_type = TREE_CHAIN (friend_args_type);
1232 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1233 decl_args_type = TREE_CHAIN (decl_args_type);
1235 return compparms (decl_args_type, friend_args_type);
1239 /* DECL is a TYPE_DECL */
1241 tree decl_type = TREE_TYPE (decl);
1243 /* Make sure that both DECL and FRIEND_DECL are templates or
1246 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1247 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1249 if (need_template ^ is_template)
1251 else if (is_template)
1254 /* If both are templates, check the name of the two
1255 TEMPLATE_DECL's first because is_friend didn't. */
1256 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1257 != DECL_NAME (friend_decl))
1260 /* Now check template parameter list. */
1262 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1264 return comp_template_parms
1265 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1269 return (DECL_NAME (decl)
1270 == DECL_NAME (friend_decl));
1276 /* Register the specialization SPEC as a specialization of TMPL with
1277 the indicated ARGS. IS_FRIEND indicates whether the specialization
1278 is actually just a friend declaration. Returns SPEC, or an
1279 equivalent prior declaration, if available. */
1282 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1286 spec_entry **slot = NULL;
1289 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1291 if (TREE_CODE (spec) == FUNCTION_DECL
1292 && uses_template_parms (DECL_TI_ARGS (spec)))
1293 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1294 register it; we want the corresponding TEMPLATE_DECL instead.
1295 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1296 the more obvious `uses_template_parms (spec)' to avoid problems
1297 with default function arguments. In particular, given
1298 something like this:
1300 template <class T> void f(T t1, T t = T())
1302 the default argument expression is not substituted for in an
1303 instantiation unless and until it is actually needed. */
1306 if (optimize_specialization_lookup_p (tmpl))
1307 /* We don't put these specializations in the hash table, but we might
1308 want to give an error about a mismatch. */
1309 fn = retrieve_specialization (tmpl, args, 0);
1317 hash = hash_specialization (&elt);
1319 slot = (spec_entry **)
1320 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1327 /* We can sometimes try to re-register a specialization that we've
1328 already got. In particular, regenerate_decl_from_template calls
1329 duplicate_decls which will update the specialization list. But,
1330 we'll still get called again here anyhow. It's more convenient
1331 to simply allow this than to try to prevent it. */
1334 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1336 if (DECL_TEMPLATE_INSTANTIATION (fn))
1338 if (DECL_ODR_USED (fn)
1339 || DECL_EXPLICIT_INSTANTIATION (fn))
1341 error ("specialization of %qD after instantiation",
1343 return error_mark_node;
1348 /* This situation should occur only if the first
1349 specialization is an implicit instantiation, the
1350 second is an explicit specialization, and the
1351 implicit instantiation has not yet been used. That
1352 situation can occur if we have implicitly
1353 instantiated a member function and then specialized
1356 We can also wind up here if a friend declaration that
1357 looked like an instantiation turns out to be a
1360 template <class T> void foo(T);
1361 class S { friend void foo<>(int) };
1362 template <> void foo(int);
1364 We transform the existing DECL in place so that any
1365 pointers to it become pointers to the updated
1368 If there was a definition for the template, but not
1369 for the specialization, we want this to look as if
1370 there were no definition, and vice versa. */
1371 DECL_INITIAL (fn) = NULL_TREE;
1372 duplicate_decls (spec, fn, is_friend);
1373 /* The call to duplicate_decls will have applied
1376 An explicit specialization of a function template
1377 is inline only if it is explicitly declared to be,
1378 and independently of whether its function template
1381 to the primary function; now copy the inline bits to
1382 the various clones. */
1383 FOR_EACH_CLONE (clone, fn)
1385 DECL_DECLARED_INLINE_P (clone)
1386 = DECL_DECLARED_INLINE_P (fn);
1387 DECL_SOURCE_LOCATION (clone)
1388 = DECL_SOURCE_LOCATION (fn);
1390 check_specialization_namespace (fn);
1395 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1397 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1398 /* Dup decl failed, but this is a new definition. Set the
1399 line number so any errors match this new
1401 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1407 return duplicate_decls (spec, fn, is_friend);
1409 /* A specialization must be declared in the same namespace as the
1410 template it is specializing. */
1411 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1412 && !check_specialization_namespace (tmpl))
1413 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1415 if (!optimize_specialization_lookup_p (tmpl))
1417 gcc_assert (tmpl && args && spec);
1418 *slot = ggc_alloc_spec_entry ();
1420 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1421 && PRIMARY_TEMPLATE_P (tmpl)
1422 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1423 /* TMPL is a forward declaration of a template function; keep a list
1424 of all specializations in case we need to reassign them to a friend
1425 template later in tsubst_friend_function. */
1426 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1427 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1433 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1434 TMPL and ARGS members, ignores SPEC. */
1437 eq_specializations (const void *p1, const void *p2)
1439 const spec_entry *e1 = (const spec_entry *)p1;
1440 const spec_entry *e2 = (const spec_entry *)p2;
1442 return (e1->tmpl == e2->tmpl
1443 && comp_template_args (e1->args, e2->args));
1446 /* Returns a hash for a template TMPL and template arguments ARGS. */
1449 hash_tmpl_and_args (tree tmpl, tree args)
1451 hashval_t val = DECL_UID (tmpl);
1452 return iterative_hash_template_arg (args, val);
1455 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1459 hash_specialization (const void *p)
1461 const spec_entry *e = (const spec_entry *)p;
1462 return hash_tmpl_and_args (e->tmpl, e->args);
1465 /* Recursively calculate a hash value for a template argument ARG, for use
1466 in the hash tables of template specializations. */
1469 iterative_hash_template_arg (tree arg, hashval_t val)
1471 unsigned HOST_WIDE_INT i;
1472 enum tree_code code;
1475 if (arg == NULL_TREE)
1476 return iterative_hash_object (arg, val);
1481 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1482 /* We can get one of these when re-hashing a previous entry in the middle
1483 of substituting into a pack expansion. Just look through it. */
1484 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1486 code = TREE_CODE (arg);
1487 tclass = TREE_CODE_CLASS (code);
1489 val = iterative_hash_object (code, val);
1496 case IDENTIFIER_NODE:
1497 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1501 int i, len = TREE_VEC_LENGTH (arg);
1502 for (i = 0; i < len; ++i)
1503 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1507 case TYPE_PACK_EXPANSION:
1508 case EXPR_PACK_EXPANSION:
1509 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1511 case TYPE_ARGUMENT_PACK:
1512 case NONTYPE_ARGUMENT_PACK:
1513 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1516 for (; arg; arg = TREE_CHAIN (arg))
1517 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1521 for (; arg; arg = OVL_NEXT (arg))
1522 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1528 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1530 val = iterative_hash_template_arg (field, val);
1531 val = iterative_hash_template_arg (value, val);
1537 if (!DECL_ARTIFICIAL (arg))
1539 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1540 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1542 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1545 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1548 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1549 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1551 case TEMPLATE_PARM_INDEX:
1552 val = iterative_hash_template_arg
1553 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1554 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1555 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1558 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1559 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1560 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1563 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1565 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1569 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1570 code = TREE_CODE (TREE_OPERAND (arg, 1));
1571 val = iterative_hash_object (code, val);
1572 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1575 /* A lambda can't appear in a template arg, but don't crash on
1577 gcc_assert (seen_error ());
1581 case STATIC_CAST_EXPR:
1582 case REINTERPRET_CAST_EXPR:
1583 case CONST_CAST_EXPR:
1584 case DYNAMIC_CAST_EXPR:
1586 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1587 /* Now hash operands as usual. */
1597 if (TYPE_CANONICAL (arg))
1598 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1600 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1601 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1602 /* Otherwise just compare the types during lookup. */
1605 case tcc_declaration:
1607 return iterative_hash_expr (arg, val);
1610 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1612 unsigned n = TREE_OPERAND_LENGTH (arg);
1613 for (i = 0; i < n; ++i)
1614 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1622 /* Unregister the specialization SPEC as a specialization of TMPL.
1623 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1624 if the SPEC was listed as a specialization of TMPL.
1626 Note that SPEC has been ggc_freed, so we can't look inside it. */
1629 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1634 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1635 elt.args = TI_ARGS (tinfo);
1636 elt.spec = NULL_TREE;
1638 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1641 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1642 gcc_assert (new_spec != NULL_TREE);
1643 (*slot)->spec = new_spec;
1650 /* Compare an entry in the local specializations hash table P1 (which
1651 is really a pointer to a TREE_LIST) with P2 (which is really a
1655 eq_local_specializations (const void *p1, const void *p2)
1657 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1660 /* Hash P1, an entry in the local specializations table. */
1663 hash_local_specialization (const void* p1)
1665 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1668 /* Like register_specialization, but for local declarations. We are
1669 registering SPEC, an instantiation of TMPL. */
1672 register_local_specialization (tree spec, tree tmpl)
1676 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1677 htab_hash_pointer (tmpl), INSERT);
1678 *slot = build_tree_list (spec, tmpl);
1681 /* TYPE is a class type. Returns true if TYPE is an explicitly
1682 specialized class. */
1685 explicit_class_specialization_p (tree type)
1687 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1689 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1692 /* Print the list of functions at FNS, going through all the overloads
1693 for each element of the list. Alternatively, FNS can not be a
1694 TREE_LIST, in which case it will be printed together with all the
1697 MORE and *STR should respectively be FALSE and NULL when the function
1698 is called from the outside. They are used internally on recursive
1699 calls. print_candidates manages the two parameters and leaves NULL
1700 in *STR when it ends. */
1703 print_candidates_1 (tree fns, bool more, const char **str)
1706 char *spaces = NULL;
1708 for (fn = fns; fn; fn = OVL_NEXT (fn))
1709 if (TREE_CODE (fn) == TREE_LIST)
1711 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1712 print_candidates_1 (TREE_VALUE (fn2),
1713 TREE_CHAIN (fn2) || more, str);
1719 /* Pick the prefix string. */
1720 if (!more && !OVL_NEXT (fns))
1722 error ("candidate is: %+#D", OVL_CURRENT (fn));
1726 *str = _("candidates are:");
1727 spaces = get_spaces (*str);
1729 error ("%s %+#D", *str, OVL_CURRENT (fn));
1730 *str = spaces ? spaces : *str;
1740 /* Print the list of candidate FNS in an error message. FNS can also
1741 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1744 print_candidates (tree fns)
1746 const char *str = NULL;
1747 print_candidates_1 (fns, false, &str);
1748 gcc_assert (str == NULL);
1751 /* Returns the template (one of the functions given by TEMPLATE_ID)
1752 which can be specialized to match the indicated DECL with the
1753 explicit template args given in TEMPLATE_ID. The DECL may be
1754 NULL_TREE if none is available. In that case, the functions in
1755 TEMPLATE_ID are non-members.
1757 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1758 specialization of a member template.
1760 The TEMPLATE_COUNT is the number of references to qualifying
1761 template classes that appeared in the name of the function. See
1762 check_explicit_specialization for a more accurate description.
1764 TSK indicates what kind of template declaration (if any) is being
1765 declared. TSK_TEMPLATE indicates that the declaration given by
1766 DECL, though a FUNCTION_DECL, has template parameters, and is
1767 therefore a template function.
1769 The template args (those explicitly specified and those deduced)
1770 are output in a newly created vector *TARGS_OUT.
1772 If it is impossible to determine the result, an error message is
1773 issued. The error_mark_node is returned to indicate failure. */
1776 determine_specialization (tree template_id,
1779 int need_member_template,
1785 tree explicit_targs;
1786 tree candidates = NULL_TREE;
1787 /* A TREE_LIST of templates of which DECL may be a specialization.
1788 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1789 corresponding TREE_PURPOSE is the set of template arguments that,
1790 when used to instantiate the template, would produce a function
1791 with the signature of DECL. */
1792 tree templates = NULL_TREE;
1794 struct cp_binding_level *b;
1796 *targs_out = NULL_TREE;
1798 if (template_id == error_mark_node || decl == error_mark_node)
1799 return error_mark_node;
1801 fns = TREE_OPERAND (template_id, 0);
1802 explicit_targs = TREE_OPERAND (template_id, 1);
1804 if (fns == error_mark_node)
1805 return error_mark_node;
1807 /* Check for baselinks. */
1808 if (BASELINK_P (fns))
1809 fns = BASELINK_FUNCTIONS (fns);
1811 if (!is_overloaded_fn (fns))
1813 error ("%qD is not a function template", fns);
1814 return error_mark_node;
1817 /* Count the number of template headers specified for this
1820 for (b = current_binding_level;
1821 b->kind == sk_template_parms;
1825 for (; fns; fns = OVL_NEXT (fns))
1827 tree fn = OVL_CURRENT (fns);
1829 if (TREE_CODE (fn) == TEMPLATE_DECL)
1831 tree decl_arg_types;
1834 /* In case of explicit specialization, we need to check if
1835 the number of template headers appearing in the specialization
1836 is correct. This is usually done in check_explicit_specialization,
1837 but the check done there cannot be exhaustive when specializing
1838 member functions. Consider the following code:
1840 template <> void A<int>::f(int);
1841 template <> template <> void A<int>::f(int);
1843 Assuming that A<int> is not itself an explicit specialization
1844 already, the first line specializes "f" which is a non-template
1845 member function, whilst the second line specializes "f" which
1846 is a template member function. So both lines are syntactically
1847 correct, and check_explicit_specialization does not reject
1850 Here, we can do better, as we are matching the specialization
1851 against the declarations. We count the number of template
1852 headers, and we check if they match TEMPLATE_COUNT + 1
1853 (TEMPLATE_COUNT is the number of qualifying template classes,
1854 plus there must be another header for the member template
1857 Notice that if header_count is zero, this is not a
1858 specialization but rather a template instantiation, so there
1859 is no check we can perform here. */
1860 if (header_count && header_count != template_count + 1)
1863 /* Check that the number of template arguments at the
1864 innermost level for DECL is the same as for FN. */
1865 if (current_binding_level->kind == sk_template_parms
1866 && !current_binding_level->explicit_spec_p
1867 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1868 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1869 (current_template_parms))))
1872 /* DECL might be a specialization of FN. */
1873 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1874 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1876 /* For a non-static member function, we need to make sure
1877 that the const qualification is the same. Since
1878 get_bindings does not try to merge the "this" parameter,
1879 we must do the comparison explicitly. */
1880 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1881 && !same_type_p (TREE_VALUE (fn_arg_types),
1882 TREE_VALUE (decl_arg_types)))
1885 /* Skip the "this" parameter and, for constructors of
1886 classes with virtual bases, the VTT parameter. A
1887 full specialization of a constructor will have a VTT
1888 parameter, but a template never will. */
1890 = skip_artificial_parms_for (decl, decl_arg_types);
1892 = skip_artificial_parms_for (fn, fn_arg_types);
1894 /* Check that the number of function parameters matches.
1896 template <class T> void f(int i = 0);
1897 template <> void f<int>();
1898 The specialization f<int> is invalid but is not caught
1899 by get_bindings below. */
1900 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1903 /* Function templates cannot be specializations; there are
1904 no partial specializations of functions. Therefore, if
1905 the type of DECL does not match FN, there is no
1907 if (tsk == tsk_template)
1909 if (compparms (fn_arg_types, decl_arg_types))
1910 candidates = tree_cons (NULL_TREE, fn, candidates);
1914 /* See whether this function might be a specialization of this
1916 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1919 /* We cannot deduce template arguments that when used to
1920 specialize TMPL will produce DECL. */
1923 /* Save this template, and the arguments deduced. */
1924 templates = tree_cons (targs, fn, templates);
1926 else if (need_member_template)
1927 /* FN is an ordinary member function, and we need a
1928 specialization of a member template. */
1930 else if (TREE_CODE (fn) != FUNCTION_DECL)
1931 /* We can get IDENTIFIER_NODEs here in certain erroneous
1934 else if (!DECL_FUNCTION_MEMBER_P (fn))
1935 /* This is just an ordinary non-member function. Nothing can
1936 be a specialization of that. */
1938 else if (DECL_ARTIFICIAL (fn))
1939 /* Cannot specialize functions that are created implicitly. */
1943 tree decl_arg_types;
1945 /* This is an ordinary member function. However, since
1946 we're here, we can assume it's enclosing class is a
1947 template class. For example,
1949 template <typename T> struct S { void f(); };
1950 template <> void S<int>::f() {}
1952 Here, S<int>::f is a non-template, but S<int> is a
1953 template class. If FN has the same type as DECL, we
1954 might be in business. */
1956 if (!DECL_TEMPLATE_INFO (fn))
1957 /* Its enclosing class is an explicit specialization
1958 of a template class. This is not a candidate. */
1961 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1962 TREE_TYPE (TREE_TYPE (fn))))
1963 /* The return types differ. */
1966 /* Adjust the type of DECL in case FN is a static member. */
1967 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1968 if (DECL_STATIC_FUNCTION_P (fn)
1969 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1970 decl_arg_types = TREE_CHAIN (decl_arg_types);
1972 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1975 candidates = tree_cons (NULL_TREE, fn, candidates);
1979 if (templates && TREE_CHAIN (templates))
1985 It is possible for a specialization with a given function
1986 signature to be instantiated from more than one function
1987 template. In such cases, explicit specification of the
1988 template arguments must be used to uniquely identify the
1989 function template specialization being specialized.
1991 Note that here, there's no suggestion that we're supposed to
1992 determine which of the candidate templates is most
1993 specialized. However, we, also have:
1997 Partial ordering of overloaded function template
1998 declarations is used in the following contexts to select
1999 the function template to which a function template
2000 specialization refers:
2002 -- when an explicit specialization refers to a function
2005 So, we do use the partial ordering rules, at least for now.
2006 This extension can only serve to make invalid programs valid,
2007 so it's safe. And, there is strong anecdotal evidence that
2008 the committee intended the partial ordering rules to apply;
2009 the EDG front end has that behavior, and John Spicer claims
2010 that the committee simply forgot to delete the wording in
2011 [temp.expl.spec]. */
2012 tree tmpl = most_specialized_instantiation (templates);
2013 if (tmpl != error_mark_node)
2016 TREE_CHAIN (templates) = NULL_TREE;
2020 if (templates == NULL_TREE && candidates == NULL_TREE)
2022 error ("template-id %qD for %q+D does not match any template "
2023 "declaration", template_id, decl);
2024 if (header_count && header_count != template_count + 1)
2025 inform (input_location, "saw %d %<template<>%>, need %d for "
2026 "specializing a member function template",
2027 header_count, template_count + 1);
2028 return error_mark_node;
2030 else if ((templates && TREE_CHAIN (templates))
2031 || (candidates && TREE_CHAIN (candidates))
2032 || (templates && candidates))
2034 error ("ambiguous template specialization %qD for %q+D",
2036 candidates = chainon (candidates, templates);
2037 print_candidates (candidates);
2038 return error_mark_node;
2041 /* We have one, and exactly one, match. */
2044 tree fn = TREE_VALUE (candidates);
2045 *targs_out = copy_node (DECL_TI_ARGS (fn));
2046 /* DECL is a re-declaration or partial instantiation of a template
2048 if (TREE_CODE (fn) == TEMPLATE_DECL)
2050 /* It was a specialization of an ordinary member function in a
2052 return DECL_TI_TEMPLATE (fn);
2055 /* It was a specialization of a template. */
2056 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2057 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2059 *targs_out = copy_node (targs);
2060 SET_TMPL_ARGS_LEVEL (*targs_out,
2061 TMPL_ARGS_DEPTH (*targs_out),
2062 TREE_PURPOSE (templates));
2065 *targs_out = TREE_PURPOSE (templates);
2066 return TREE_VALUE (templates);
2069 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2070 but with the default argument values filled in from those in the
2074 copy_default_args_to_explicit_spec_1 (tree spec_types,
2077 tree new_spec_types;
2082 if (spec_types == void_list_node)
2083 return void_list_node;
2085 /* Substitute into the rest of the list. */
2087 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2088 TREE_CHAIN (tmpl_types));
2090 /* Add the default argument for this parameter. */
2091 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2092 TREE_VALUE (spec_types),
2096 /* DECL is an explicit specialization. Replicate default arguments
2097 from the template it specializes. (That way, code like:
2099 template <class T> void f(T = 3);
2100 template <> void f(double);
2103 works, as required.) An alternative approach would be to look up
2104 the correct default arguments at the call-site, but this approach
2105 is consistent with how implicit instantiations are handled. */
2108 copy_default_args_to_explicit_spec (tree decl)
2113 tree new_spec_types;
2117 tree object_type = NULL_TREE;
2118 tree in_charge = NULL_TREE;
2119 tree vtt = NULL_TREE;
2121 /* See if there's anything we need to do. */
2122 tmpl = DECL_TI_TEMPLATE (decl);
2123 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2124 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2125 if (TREE_PURPOSE (t))
2130 old_type = TREE_TYPE (decl);
2131 spec_types = TYPE_ARG_TYPES (old_type);
2133 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2135 /* Remove the this pointer, but remember the object's type for
2137 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2138 spec_types = TREE_CHAIN (spec_types);
2139 tmpl_types = TREE_CHAIN (tmpl_types);
2141 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2143 /* DECL may contain more parameters than TMPL due to the extra
2144 in-charge parameter in constructors and destructors. */
2145 in_charge = spec_types;
2146 spec_types = TREE_CHAIN (spec_types);
2148 if (DECL_HAS_VTT_PARM_P (decl))
2151 spec_types = TREE_CHAIN (spec_types);
2155 /* Compute the merged default arguments. */
2157 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2159 /* Compute the new FUNCTION_TYPE. */
2163 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2168 /* Put the in-charge parameter back. */
2169 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2170 TREE_VALUE (in_charge),
2173 new_type = build_method_type_directly (object_type,
2174 TREE_TYPE (old_type),
2178 new_type = build_function_type (TREE_TYPE (old_type),
2180 new_type = cp_build_type_attribute_variant (new_type,
2181 TYPE_ATTRIBUTES (old_type));
2182 new_type = build_exception_variant (new_type,
2183 TYPE_RAISES_EXCEPTIONS (old_type));
2184 TREE_TYPE (decl) = new_type;
2187 /* Check to see if the function just declared, as indicated in
2188 DECLARATOR, and in DECL, is a specialization of a function
2189 template. We may also discover that the declaration is an explicit
2190 instantiation at this point.
2192 Returns DECL, or an equivalent declaration that should be used
2193 instead if all goes well. Issues an error message if something is
2194 amiss. Returns error_mark_node if the error is not easily
2197 FLAGS is a bitmask consisting of the following flags:
2199 2: The function has a definition.
2200 4: The function is a friend.
2202 The TEMPLATE_COUNT is the number of references to qualifying
2203 template classes that appeared in the name of the function. For
2206 template <class T> struct S { void f(); };
2209 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2210 classes are not counted in the TEMPLATE_COUNT, so that in
2212 template <class T> struct S {};
2213 template <> struct S<int> { void f(); }
2214 template <> void S<int>::f();
2216 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2217 invalid; there should be no template <>.)
2219 If the function is a specialization, it is marked as such via
2220 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2221 is set up correctly, and it is added to the list of specializations
2222 for that template. */
2225 check_explicit_specialization (tree declarator,
2230 int have_def = flags & 2;
2231 int is_friend = flags & 4;
2232 int specialization = 0;
2233 int explicit_instantiation = 0;
2234 int member_specialization = 0;
2235 tree ctype = DECL_CLASS_CONTEXT (decl);
2236 tree dname = DECL_NAME (decl);
2241 if (!processing_specialization)
2244 tsk = tsk_excessive_parms;
2247 tsk = current_tmpl_spec_kind (template_count);
2252 if (processing_specialization)
2255 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2257 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2260 /* This could be something like:
2262 template <class T> void f(T);
2263 class S { friend void f<>(int); } */
2267 /* This case handles bogus declarations like template <>
2268 template <class T> void f<int>(); */
2270 error ("template-id %qD in declaration of primary template",
2277 case tsk_invalid_member_spec:
2278 /* The error has already been reported in
2279 check_specialization_scope. */
2280 return error_mark_node;
2282 case tsk_invalid_expl_inst:
2283 error ("template parameter list used in explicit instantiation");
2289 error ("definition provided for explicit instantiation");
2291 explicit_instantiation = 1;
2294 case tsk_excessive_parms:
2295 case tsk_insufficient_parms:
2296 if (tsk == tsk_excessive_parms)
2297 error ("too many template parameter lists in declaration of %qD",
2299 else if (template_header_count)
2300 error("too few template parameter lists in declaration of %qD", decl);
2302 error("explicit specialization of %qD must be introduced by "
2303 "%<template <>%>", decl);
2307 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2309 member_specialization = 1;
2315 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2317 /* This case handles bogus declarations like template <>
2318 template <class T> void f<int>(); */
2320 if (uses_template_parms (declarator))
2321 error ("function template partial specialization %qD "
2322 "is not allowed", declarator);
2324 error ("template-id %qD in declaration of primary template",
2329 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2330 /* This is a specialization of a member template, without
2331 specialization the containing class. Something like:
2333 template <class T> struct S {
2334 template <class U> void f (U);
2336 template <> template <class U> void S<int>::f(U) {}
2338 That's a specialization -- but of the entire template. */
2346 if (specialization || member_specialization)
2348 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2349 for (; t; t = TREE_CHAIN (t))
2350 if (TREE_PURPOSE (t))
2352 permerror (input_location,
2353 "default argument specified in explicit specialization");
2358 if (specialization || member_specialization || explicit_instantiation)
2360 tree tmpl = NULL_TREE;
2361 tree targs = NULL_TREE;
2363 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2364 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2368 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2373 /* If there is no class context, the explicit instantiation
2374 must be at namespace scope. */
2375 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2377 /* Find the namespace binding, using the declaration
2379 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2381 if (fns == error_mark_node || !is_overloaded_fn (fns))
2383 error ("%qD is not a template function", dname);
2384 fns = error_mark_node;
2388 tree fn = OVL_CURRENT (fns);
2389 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2390 CP_DECL_CONTEXT (fn)))
2391 error ("%qD is not declared in %qD",
2392 decl, current_namespace);
2396 declarator = lookup_template_function (fns, NULL_TREE);
2399 if (declarator == error_mark_node)
2400 return error_mark_node;
2402 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2404 if (!explicit_instantiation)
2405 /* A specialization in class scope. This is invalid,
2406 but the error will already have been flagged by
2407 check_specialization_scope. */
2408 return error_mark_node;
2411 /* It's not valid to write an explicit instantiation in
2414 class C { template void f(); }
2416 This case is caught by the parser. However, on
2419 template class C { void f(); };
2421 (which is invalid) we can get here. The error will be
2428 else if (ctype != NULL_TREE
2429 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2432 /* Find the list of functions in ctype that have the same
2433 name as the declared function. */
2434 tree name = TREE_OPERAND (declarator, 0);
2435 tree fns = NULL_TREE;
2438 if (constructor_name_p (name, ctype))
2440 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2442 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2443 : !CLASSTYPE_DESTRUCTORS (ctype))
2445 /* From [temp.expl.spec]:
2447 If such an explicit specialization for the member
2448 of a class template names an implicitly-declared
2449 special member function (clause _special_), the
2450 program is ill-formed.
2452 Similar language is found in [temp.explicit]. */
2453 error ("specialization of implicitly-declared special member function");
2454 return error_mark_node;
2457 name = is_constructor ? ctor_identifier : dtor_identifier;
2460 if (!DECL_CONV_FN_P (decl))
2462 idx = lookup_fnfields_1 (ctype, name);
2464 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2468 VEC(tree,gc) *methods;
2471 /* For a type-conversion operator, we cannot do a
2472 name-based lookup. We might be looking for `operator
2473 int' which will be a specialization of `operator T'.
2474 So, we find *all* the conversion operators, and then
2475 select from them. */
2478 methods = CLASSTYPE_METHOD_VEC (ctype);
2480 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2481 VEC_iterate (tree, methods, idx, ovl);
2484 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2485 /* There are no more conversion functions. */
2488 /* Glue all these conversion functions together
2489 with those we already have. */
2490 for (; ovl; ovl = OVL_NEXT (ovl))
2491 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2495 if (fns == NULL_TREE)
2497 error ("no member function %qD declared in %qT", name, ctype);
2498 return error_mark_node;
2501 TREE_OPERAND (declarator, 0) = fns;
2504 /* Figure out what exactly is being specialized at this point.
2505 Note that for an explicit instantiation, even one for a
2506 member function, we cannot tell apriori whether the
2507 instantiation is for a member template, or just a member
2508 function of a template class. Even if a member template is
2509 being instantiated, the member template arguments may be
2510 elided if they can be deduced from the rest of the
2512 tmpl = determine_specialization (declarator, decl,
2514 member_specialization,
2518 if (!tmpl || tmpl == error_mark_node)
2519 /* We couldn't figure out what this declaration was
2521 return error_mark_node;
2524 tree gen_tmpl = most_general_template (tmpl);
2526 if (explicit_instantiation)
2528 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2529 is done by do_decl_instantiation later. */
2531 int arg_depth = TMPL_ARGS_DEPTH (targs);
2532 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2534 if (arg_depth > parm_depth)
2536 /* If TMPL is not the most general template (for
2537 example, if TMPL is a friend template that is
2538 injected into namespace scope), then there will
2539 be too many levels of TARGS. Remove some of them
2544 new_targs = make_tree_vec (parm_depth);
2545 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2546 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2547 = TREE_VEC_ELT (targs, i);
2551 return instantiate_template (tmpl, targs, tf_error);
2554 /* If we thought that the DECL was a member function, but it
2555 turns out to be specializing a static member function,
2556 make DECL a static member function as well. */
2557 if (DECL_STATIC_FUNCTION_P (tmpl)
2558 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2559 revert_static_member_fn (decl);
2561 /* If this is a specialization of a member template of a
2562 template class, we want to return the TEMPLATE_DECL, not
2563 the specialization of it. */
2564 if (tsk == tsk_template)
2566 tree result = DECL_TEMPLATE_RESULT (tmpl);
2567 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2568 DECL_INITIAL (result) = NULL_TREE;
2572 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2573 DECL_SOURCE_LOCATION (result)
2574 = DECL_SOURCE_LOCATION (decl);
2575 /* We want to use the argument list specified in the
2576 definition, not in the original declaration. */
2577 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2578 for (parm = DECL_ARGUMENTS (result); parm;
2579 parm = DECL_CHAIN (parm))
2580 DECL_CONTEXT (parm) = result;
2582 return register_specialization (tmpl, gen_tmpl, targs,
2586 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2587 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2589 /* Inherit default function arguments from the template
2590 DECL is specializing. */
2591 copy_default_args_to_explicit_spec (decl);
2593 /* This specialization has the same protection as the
2594 template it specializes. */
2595 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2596 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2598 /* 7.1.1-1 [dcl.stc]
2600 A storage-class-specifier shall not be specified in an
2601 explicit specialization...
2603 The parser rejects these, so unless action is taken here,
2604 explicit function specializations will always appear with
2607 The action recommended by the C++ CWG in response to C++
2608 defect report 605 is to make the storage class and linkage
2609 of the explicit specialization match the templated function:
2611 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2613 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2615 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2616 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2618 /* This specialization has the same linkage and visibility as
2619 the function template it specializes. */
2620 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2621 if (! TREE_PUBLIC (decl))
2623 DECL_INTERFACE_KNOWN (decl) = 1;
2624 DECL_NOT_REALLY_EXTERN (decl) = 1;
2626 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2627 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2629 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2630 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2634 /* If DECL is a friend declaration, declared using an
2635 unqualified name, the namespace associated with DECL may
2636 have been set incorrectly. For example, in:
2638 template <typename T> void f(T);
2640 struct S { friend void f<int>(int); }
2643 we will have set the DECL_CONTEXT for the friend
2644 declaration to N, rather than to the global namespace. */
2645 if (DECL_NAMESPACE_SCOPE_P (decl))
2646 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2648 if (is_friend && !have_def)
2649 /* This is not really a declaration of a specialization.
2650 It's just the name of an instantiation. But, it's not
2651 a request for an instantiation, either. */
2652 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2653 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2654 /* This is indeed a specialization. In case of constructors
2655 and destructors, we need in-charge and not-in-charge
2656 versions in V3 ABI. */
2657 clone_function_decl (decl, /*update_method_vec_p=*/0);
2659 /* Register this specialization so that we can find it
2661 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2668 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2669 parameters. These are represented in the same format used for
2670 DECL_TEMPLATE_PARMS. */
2673 comp_template_parms (const_tree parms1, const_tree parms2)
2678 if (parms1 == parms2)
2681 for (p1 = parms1, p2 = parms2;
2682 p1 != NULL_TREE && p2 != NULL_TREE;
2683 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2685 tree t1 = TREE_VALUE (p1);
2686 tree t2 = TREE_VALUE (p2);
2689 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2690 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2692 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2695 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2697 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2698 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2700 /* If either of the template parameters are invalid, assume
2701 they match for the sake of error recovery. */
2702 if (parm1 == error_mark_node || parm2 == error_mark_node)
2705 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2708 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2709 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2710 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2712 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2717 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2718 /* One set of parameters has more parameters lists than the
2725 /* Determine whether PARM is a parameter pack. */
2728 template_parameter_pack_p (const_tree parm)
2730 /* Determine if we have a non-type template parameter pack. */
2731 if (TREE_CODE (parm) == PARM_DECL)
2732 return (DECL_TEMPLATE_PARM_P (parm)
2733 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2735 /* If this is a list of template parameters, we could get a
2736 TYPE_DECL or a TEMPLATE_DECL. */
2737 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2738 parm = TREE_TYPE (parm);
2740 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2741 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2742 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2745 /* Determine if T is a function parameter pack. */
2748 function_parameter_pack_p (const_tree t)
2750 if (t && TREE_CODE (t) == PARM_DECL)
2751 return FUNCTION_PARAMETER_PACK_P (t);
2755 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2756 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2759 get_function_template_decl (const_tree primary_func_tmpl_inst)
2761 if (! primary_func_tmpl_inst
2762 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2763 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2766 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2769 /* Return true iff the function parameter PARAM_DECL was expanded
2770 from the function parameter pack PACK. */
2773 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2775 if (DECL_ARTIFICIAL (param_decl)
2776 || !function_parameter_pack_p (pack))
2779 /* The parameter pack and its pack arguments have the same
2781 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2784 /* Determine whether ARGS describes a variadic template args list,
2785 i.e., one that is terminated by a template argument pack. */
2788 template_args_variadic_p (tree args)
2793 if (args == NULL_TREE)
2796 args = INNERMOST_TEMPLATE_ARGS (args);
2797 nargs = TREE_VEC_LENGTH (args);
2802 last_parm = TREE_VEC_ELT (args, nargs - 1);
2804 return ARGUMENT_PACK_P (last_parm);
2807 /* Generate a new name for the parameter pack name NAME (an
2808 IDENTIFIER_NODE) that incorporates its */
2811 make_ith_pack_parameter_name (tree name, int i)
2813 /* Munge the name to include the parameter index. */
2814 #define NUMBUF_LEN 128
2815 char numbuf[NUMBUF_LEN];
2819 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2820 newname_len = IDENTIFIER_LENGTH (name)
2821 + strlen (numbuf) + 2;
2822 newname = (char*)alloca (newname_len);
2823 snprintf (newname, newname_len,
2824 "%s#%i", IDENTIFIER_POINTER (name), i);
2825 return get_identifier (newname);
2828 /* Return true if T is a primary function
2829 or class template instantiation. */
2832 primary_template_instantiation_p (const_tree t)
2837 if (TREE_CODE (t) == FUNCTION_DECL)
2838 return DECL_LANG_SPECIFIC (t)
2839 && DECL_TEMPLATE_INSTANTIATION (t)
2840 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2841 else if (CLASS_TYPE_P (t))
2842 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2843 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2847 /* Return true if PARM is a template template parameter. */
2850 template_template_parameter_p (const_tree parm)
2852 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2855 /* Return the template parameters of T if T is a
2856 primary template instantiation, NULL otherwise. */
2859 get_primary_template_innermost_parameters (const_tree t)
2861 tree parms = NULL, template_info = NULL;
2863 if ((template_info = get_template_info (t))
2864 && primary_template_instantiation_p (t))
2865 parms = INNERMOST_TEMPLATE_PARMS
2866 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2871 /* Return the template parameters of the LEVELth level from the full list
2872 of template parameters PARMS. */
2875 get_template_parms_at_level (tree parms, int level)
2879 || TREE_CODE (parms) != TREE_LIST
2880 || level > TMPL_PARMS_DEPTH (parms))
2883 for (p = parms; p; p = TREE_CHAIN (p))
2884 if (TMPL_PARMS_DEPTH (p) == level)
2890 /* Returns the template arguments of T if T is a template instantiation,
2894 get_template_innermost_arguments (const_tree t)
2896 tree args = NULL, template_info = NULL;
2898 if ((template_info = get_template_info (t))
2899 && TI_ARGS (template_info))
2900 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2905 /* Return the argument pack elements of T if T is a template argument pack,
2909 get_template_argument_pack_elems (const_tree t)
2911 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2912 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2915 return ARGUMENT_PACK_ARGS (t);
2918 /* Structure used to track the progress of find_parameter_packs_r. */
2919 struct find_parameter_pack_data
2921 /* TREE_LIST that will contain all of the parameter packs found by
2923 tree* parameter_packs;
2925 /* Set of AST nodes that have been visited by the traversal. */
2926 struct pointer_set_t *visited;
2929 /* Identifies all of the argument packs that occur in a template
2930 argument and appends them to the TREE_LIST inside DATA, which is a
2931 find_parameter_pack_data structure. This is a subroutine of
2932 make_pack_expansion and uses_parameter_packs. */
2934 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2937 struct find_parameter_pack_data* ppd =
2938 (struct find_parameter_pack_data*)data;
2939 bool parameter_pack_p = false;
2941 /* Identify whether this is a parameter pack or not. */
2942 switch (TREE_CODE (t))
2944 case TEMPLATE_PARM_INDEX:
2945 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2946 parameter_pack_p = true;
2949 case TEMPLATE_TYPE_PARM:
2950 case TEMPLATE_TEMPLATE_PARM:
2951 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2952 parameter_pack_p = true;
2956 if (FUNCTION_PARAMETER_PACK_P (t))
2958 /* We don't want to walk into the type of a PARM_DECL,
2959 because we don't want to see the type parameter pack. */
2961 parameter_pack_p = true;
2966 /* Not a parameter pack. */
2970 if (parameter_pack_p)
2972 /* Add this parameter pack to the list. */
2973 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2977 cp_walk_tree (&TYPE_CONTEXT (t),
2978 &find_parameter_packs_r, ppd, ppd->visited);
2980 /* This switch statement will return immediately if we don't find a
2982 switch (TREE_CODE (t))
2984 case TEMPLATE_PARM_INDEX:
2987 case BOUND_TEMPLATE_TEMPLATE_PARM:
2988 /* Check the template itself. */
2989 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2990 &find_parameter_packs_r, ppd, ppd->visited);
2991 /* Check the template arguments. */
2992 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2997 case TEMPLATE_TYPE_PARM:
2998 case TEMPLATE_TEMPLATE_PARM:
3005 if (TYPE_PTRMEMFUNC_P (t))
3011 if (TYPE_TEMPLATE_INFO (t))
3012 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3013 &find_parameter_packs_r, ppd, ppd->visited);
3019 cp_walk_tree (&TREE_TYPE (t),
3020 &find_parameter_packs_r, ppd, ppd->visited);
3024 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3029 case TYPE_PACK_EXPANSION:
3030 case EXPR_PACK_EXPANSION:
3035 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3040 case IDENTIFIER_NODE:
3041 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3053 /* Determines if the expression or type T uses any parameter packs. */
3055 uses_parameter_packs (tree t)
3057 tree parameter_packs = NULL_TREE;
3058 struct find_parameter_pack_data ppd;
3059 ppd.parameter_packs = ¶meter_packs;
3060 ppd.visited = pointer_set_create ();
3061 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3062 pointer_set_destroy (ppd.visited);
3063 return parameter_packs != NULL_TREE;
3066 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3067 representation a base-class initializer into a parameter pack
3068 expansion. If all goes well, the resulting node will be an
3069 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3072 make_pack_expansion (tree arg)
3075 tree parameter_packs = NULL_TREE;
3076 bool for_types = false;
3077 struct find_parameter_pack_data ppd;
3079 if (!arg || arg == error_mark_node)
3082 if (TREE_CODE (arg) == TREE_LIST)
3084 /* The only time we will see a TREE_LIST here is for a base
3085 class initializer. In this case, the TREE_PURPOSE will be a
3086 _TYPE node (representing the base class expansion we're
3087 initializing) and the TREE_VALUE will be a TREE_LIST
3088 containing the initialization arguments.
3090 The resulting expansion looks somewhat different from most
3091 expansions. Rather than returning just one _EXPANSION, we
3092 return a TREE_LIST whose TREE_PURPOSE is a
3093 TYPE_PACK_EXPANSION containing the bases that will be
3094 initialized. The TREE_VALUE will be identical to the
3095 original TREE_VALUE, which is a list of arguments that will
3096 be passed to each base. We do not introduce any new pack
3097 expansion nodes into the TREE_VALUE (although it is possible
3098 that some already exist), because the TREE_PURPOSE and
3099 TREE_VALUE all need to be expanded together with the same
3100 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3101 resulting TREE_PURPOSE will mention the parameter packs in
3102 both the bases and the arguments to the bases. */
3105 tree parameter_packs = NULL_TREE;
3107 /* Determine which parameter packs will be used by the base
3109 ppd.visited = pointer_set_create ();
3110 ppd.parameter_packs = ¶meter_packs;
3111 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3114 if (parameter_packs == NULL_TREE)
3116 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3117 pointer_set_destroy (ppd.visited);
3118 return error_mark_node;
3121 if (TREE_VALUE (arg) != void_type_node)
3123 /* Collect the sets of parameter packs used in each of the
3124 initialization arguments. */
3125 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3127 /* Determine which parameter packs will be expanded in this
3129 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3134 pointer_set_destroy (ppd.visited);
3136 /* Create the pack expansion type for the base type. */
3137 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3138 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3139 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3141 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3142 they will rarely be compared to anything. */
3143 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3145 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3148 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3151 /* Build the PACK_EXPANSION_* node. */
3153 ? cxx_make_type (TYPE_PACK_EXPANSION)
3154 : make_node (EXPR_PACK_EXPANSION);
3155 SET_PACK_EXPANSION_PATTERN (result, arg);
3156 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3158 /* Propagate type and const-expression information. */
3159 TREE_TYPE (result) = TREE_TYPE (arg);
3160 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3163 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3164 they will rarely be compared to anything. */
3165 SET_TYPE_STRUCTURAL_EQUALITY (result);
3167 /* Determine which parameter packs will be expanded. */
3168 ppd.parameter_packs = ¶meter_packs;
3169 ppd.visited = pointer_set_create ();
3170 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3171 pointer_set_destroy (ppd.visited);
3173 /* Make sure we found some parameter packs. */
3174 if (parameter_packs == NULL_TREE)
3177 error ("expansion pattern %<%T%> contains no argument packs", arg);
3179 error ("expansion pattern %<%E%> contains no argument packs", arg);
3180 return error_mark_node;
3182 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3187 /* Checks T for any "bare" parameter packs, which have not yet been
3188 expanded, and issues an error if any are found. This operation can
3189 only be done on full expressions or types (e.g., an expression
3190 statement, "if" condition, etc.), because we could have expressions like:
3192 foo(f(g(h(args)))...)
3194 where "args" is a parameter pack. check_for_bare_parameter_packs
3195 should not be called for the subexpressions args, h(args),
3196 g(h(args)), or f(g(h(args))), because we would produce erroneous
3199 Returns TRUE and emits an error if there were bare parameter packs,
3200 returns FALSE otherwise. */
3202 check_for_bare_parameter_packs (tree t)
3204 tree parameter_packs = NULL_TREE;
3205 struct find_parameter_pack_data ppd;
3207 if (!processing_template_decl || !t || t == error_mark_node)
3210 if (TREE_CODE (t) == TYPE_DECL)
3213 ppd.parameter_packs = ¶meter_packs;
3214 ppd.visited = pointer_set_create ();
3215 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3216 pointer_set_destroy (ppd.visited);
3218 if (parameter_packs)
3220 error ("parameter packs not expanded with %<...%>:");
3221 while (parameter_packs)
3223 tree pack = TREE_VALUE (parameter_packs);
3224 tree name = NULL_TREE;
3226 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3227 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3228 name = TYPE_NAME (pack);
3229 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3230 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3232 name = DECL_NAME (pack);
3235 inform (input_location, " %qD", name);
3237 inform (input_location, " <anonymous>");
3239 parameter_packs = TREE_CHAIN (parameter_packs);
3248 /* Expand any parameter packs that occur in the template arguments in
3251 expand_template_argument_pack (tree args)
3253 tree result_args = NULL_TREE;
3254 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3255 int num_result_args = -1;
3256 int non_default_args_count = -1;
3258 /* First, determine if we need to expand anything, and the number of
3259 slots we'll need. */
3260 for (in_arg = 0; in_arg < nargs; ++in_arg)
3262 tree arg = TREE_VEC_ELT (args, in_arg);
3263 if (arg == NULL_TREE)
3265 if (ARGUMENT_PACK_P (arg))
3267 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3268 if (num_result_args < 0)
3269 num_result_args = in_arg + num_packed;
3271 num_result_args += num_packed;
3275 if (num_result_args >= 0)
3280 /* If no expansion is necessary, we're done. */
3281 if (num_result_args < 0)
3284 /* Expand arguments. */
3285 result_args = make_tree_vec (num_result_args);
3286 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3287 non_default_args_count =
3288 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3289 for (in_arg = 0; in_arg < nargs; ++in_arg)
3291 tree arg = TREE_VEC_ELT (args, in_arg);
3292 if (ARGUMENT_PACK_P (arg))
3294 tree packed = ARGUMENT_PACK_ARGS (arg);
3295 int i, num_packed = TREE_VEC_LENGTH (packed);
3296 for (i = 0; i < num_packed; ++i, ++out_arg)
3297 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3298 if (non_default_args_count > 0)
3299 non_default_args_count += num_packed;
3303 TREE_VEC_ELT (result_args, out_arg) = arg;
3307 if (non_default_args_count >= 0)
3308 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3312 /* Checks if DECL shadows a template parameter.
3314 [temp.local]: A template-parameter shall not be redeclared within its
3315 scope (including nested scopes).
3317 Emits an error and returns TRUE if the DECL shadows a parameter,
3318 returns FALSE otherwise. */
3321 check_template_shadow (tree decl)
3325 /* If we're not in a template, we can't possibly shadow a template
3327 if (!current_template_parms)
3330 /* Figure out what we're shadowing. */
3331 if (TREE_CODE (decl) == OVERLOAD)
3332 decl = OVL_CURRENT (decl);
3333 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3335 /* If there's no previous binding for this name, we're not shadowing
3336 anything, let alone a template parameter. */
3340 /* If we're not shadowing a template parameter, we're done. Note
3341 that OLDDECL might be an OVERLOAD (or perhaps even an
3342 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3344 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3347 /* We check for decl != olddecl to avoid bogus errors for using a
3348 name inside a class. We check TPFI to avoid duplicate errors for
3349 inline member templates. */
3351 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3354 error ("declaration of %q+#D", decl);
3355 error (" shadows template parm %q+#D", olddecl);
3359 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3360 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3361 template parameters. */
3364 build_template_parm_index (int index,
3371 tree t = make_node (TEMPLATE_PARM_INDEX);
3372 TEMPLATE_PARM_IDX (t) = index;
3373 TEMPLATE_PARM_LEVEL (t) = level;
3374 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3375 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3376 TEMPLATE_PARM_DECL (t) = decl;
3377 TREE_TYPE (t) = type;
3378 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3379 TREE_READONLY (t) = TREE_READONLY (decl);
3384 /* Find the canonical type parameter for the given template type
3385 parameter. Returns the canonical type parameter, which may be TYPE
3386 if no such parameter existed. */
3389 canonical_type_parameter (tree type)
3392 int idx = TEMPLATE_TYPE_IDX (type);
3393 if (!canonical_template_parms)
3394 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3396 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3397 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3399 list = VEC_index (tree, canonical_template_parms, idx);
3400 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3401 list = TREE_CHAIN (list);
3404 return TREE_VALUE (list);
3407 VEC_replace(tree, canonical_template_parms, idx,
3408 tree_cons (NULL_TREE, type,
3409 VEC_index (tree, canonical_template_parms, idx)));
3414 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3415 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3416 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3417 new one is created. */
3420 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3421 tsubst_flags_t complain)
3423 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3424 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3425 != TEMPLATE_PARM_LEVEL (index) - levels)
3426 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3428 tree orig_decl = TEMPLATE_PARM_DECL (index);
3431 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3432 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3433 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3434 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3435 DECL_ARTIFICIAL (decl) = 1;
3436 SET_DECL_TEMPLATE_PARM_P (decl);
3438 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3439 TEMPLATE_PARM_LEVEL (index) - levels,
3440 TEMPLATE_PARM_ORIG_LEVEL (index),
3441 TEMPLATE_PARM_NUM_SIBLINGS (index),
3443 TEMPLATE_PARM_DESCENDANTS (index) = t;
3444 TEMPLATE_PARM_PARAMETER_PACK (t)
3445 = TEMPLATE_PARM_PARAMETER_PACK (index);
3447 /* Template template parameters need this. */
3448 if (TREE_CODE (decl) == TEMPLATE_DECL)
3449 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3450 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3454 return TEMPLATE_PARM_DESCENDANTS (index);
3457 /* Process information from new template parameter PARM and append it
3458 to the LIST being built. This new parameter is a non-type
3459 parameter iff IS_NON_TYPE is true. This new parameter is a
3460 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3461 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3462 parameter list PARM belongs to. This is used used to create a
3463 proper canonical type for the type of PARM that is to be created,
3464 iff PARM is a type. If the size is not known, this parameter shall
3468 process_template_parm (tree list, location_t parm_loc, tree parm,
3469 bool is_non_type, bool is_parameter_pack,
3470 unsigned num_template_parms)
3477 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3478 defval = TREE_PURPOSE (parm);
3482 tree p = tree_last (list);
3484 if (p && TREE_VALUE (p) != error_mark_node)
3487 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3488 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3490 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3500 parm = TREE_VALUE (parm);
3502 SET_DECL_TEMPLATE_PARM_P (parm);
3504 if (TREE_TYPE (parm) == error_mark_node)
3506 err_parm_list = build_tree_list (defval, parm);
3507 TREE_VALUE (err_parm_list) = error_mark_node;
3508 return chainon (list, err_parm_list);
3514 The top-level cv-qualifiers on the template-parameter are
3515 ignored when determining its type. */
3516 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3517 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3519 err_parm_list = build_tree_list (defval, parm);
3520 TREE_VALUE (err_parm_list) = error_mark_node;
3521 return chainon (list, err_parm_list);
3524 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3526 /* This template parameter is not a parameter pack, but it
3527 should be. Complain about "bare" parameter packs. */
3528 check_for_bare_parameter_packs (TREE_TYPE (parm));
3530 /* Recover by calling this a parameter pack. */
3531 is_parameter_pack = true;
3535 /* A template parameter is not modifiable. */
3536 TREE_CONSTANT (parm) = 1;
3537 TREE_READONLY (parm) = 1;
3538 decl = build_decl (parm_loc,
3539 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3540 TREE_CONSTANT (decl) = 1;
3541 TREE_READONLY (decl) = 1;
3542 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3543 = build_template_parm_index (idx, processing_template_decl,
3544 processing_template_decl,
3546 decl, TREE_TYPE (parm));
3548 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3549 = is_parameter_pack;
3554 parm = TREE_VALUE (TREE_VALUE (parm));
3556 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3558 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3559 /* This is for distinguishing between real templates and template
3560 template parameters */
3561 TREE_TYPE (parm) = t;
3562 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3567 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3568 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3569 decl = build_decl (parm_loc,
3570 TYPE_DECL, parm, t);
3573 TYPE_NAME (t) = decl;
3574 TYPE_STUB_DECL (t) = decl;
3576 TEMPLATE_TYPE_PARM_INDEX (t)
3577 = build_template_parm_index (idx, processing_template_decl,
3578 processing_template_decl,
3580 decl, TREE_TYPE (parm));
3581 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3582 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3584 DECL_ARTIFICIAL (decl) = 1;
3585 SET_DECL_TEMPLATE_PARM_P (decl);
3587 parm = build_tree_list (defval, parm);
3588 return chainon (list, parm);
3591 /* The end of a template parameter list has been reached. Process the
3592 tree list into a parameter vector, converting each parameter into a more
3593 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3597 end_template_parm_list (tree parms)
3601 tree saved_parmlist = make_tree_vec (list_length (parms));
3603 current_template_parms
3604 = tree_cons (size_int (processing_template_decl),
3605 saved_parmlist, current_template_parms);
3607 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3609 next = TREE_CHAIN (parm);
3610 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3611 TREE_CHAIN (parm) = NULL_TREE;
3614 --processing_template_parmlist;
3616 return saved_parmlist;
3619 /* Create a new type almost identical to TYPE but which has the
3620 following differences:
3622 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3623 template sibling parameters of T.
3625 2/ T has a new canonical type that matches the new number
3628 3/ From now on, T is going to be what lookups referring to the
3629 name of TYPE will return. No lookup should return TYPE anymore.
3631 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3633 This is a subroutine of fixup_template_parms. */
3636 fixup_template_type_parm_type (tree type, int num_parms)
3638 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3640 /* This is the decl which name is inserted into the symbol table for
3641 the template parm type. So whenever we lookup the type name, this
3642 is the DECL we get. */
3645 /* Do not fix up the type twice. */
3646 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3649 t = copy_type (type);
3650 decl = TYPE_NAME (t);
3652 TYPE_MAIN_VARIANT (t) = t;
3653 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3654 TYPE_POINTER_TO (t) = 0;
3655 TYPE_REFERENCE_TO (t) = 0;
3657 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3658 TEMPLATE_PARM_LEVEL (orig_idx),
3659 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3662 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3663 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3664 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3666 TYPE_STUB_DECL (t) = decl;
3667 TEMPLATE_TYPE_DECL (t) = decl;
3668 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3669 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3671 /* Update the type associated to the type name stored in the symbol
3672 table. Now, whenever the type name is looked up, the resulting
3673 type is properly fixed up. */
3674 TREE_TYPE (decl) = t;
3676 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3681 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3682 identical to I, but that is fixed up as to:
3684 1/ carry the number of sibling parms (NUM_PARMS) of the template
3685 parm represented by I.
3687 2/ replace all references to template parm types declared before I
3688 (in the same template parm list as I) by references to template
3689 parm types contained in ARGS. ARGS should contain the list of
3690 template parms that have been fixed up so far, in a form suitable
3691 to be passed to tsubst.
3693 This is a subroutine of fixup_template_parms. */
3696 fixup_template_parm_index (tree i, tree args, int num_parms)
3698 tree index, decl, type;
3701 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3702 /* Do not fix up the index twice. */
3703 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3706 decl = TEMPLATE_PARM_DECL (i);
3707 type = TREE_TYPE (decl);
3709 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3710 TEMPLATE_PARM_LEVEL (i),
3711 TEMPLATE_PARM_ORIG_LEVEL (i),
3715 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3716 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3718 type = tsubst (type, args, tf_none, NULL_TREE);
3720 TREE_TYPE (decl) = type;
3721 TREE_TYPE (index) = type;
3727 This is a subroutine of fixup_template_parms.
3729 It computes the canonical type of the type of the template
3730 parameter PARM_DESC and update all references to that type so that
3731 they use the newly computed canonical type. No access check is
3732 performed during the fixup. PARM_DESC is a TREE_LIST which
3733 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3734 default argument of the template parm if any. IDX is the index of
3735 the template parameter, starting at 0. NUM_PARMS is the number of
3736 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3737 TREE_VEC containing the full set of template parameters in a form
3738 suitable to be passed to substs functions as their ARGS
3739 argument. This is what current_template_args returns for a given
3740 template. The innermost vector of args in ARGLIST is the set of
3741 template parms that have been fixed up so far. This function adds
3742 the fixed up parameter into that vector. */
3745 fixup_template_parm (tree parm_desc,
3750 tree parm = TREE_VALUE (parm_desc);
3751 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3753 push_deferring_access_checks (dk_no_check);
3755 if (TREE_CODE (parm) == TYPE_DECL)
3757 /* PARM is a template type parameter. Fix up its type, add
3758 the fixed-up template parm to the vector of fixed-up
3759 template parms so far, and substitute the fixed-up
3760 template parms into the default argument of this
3763 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3764 TREE_TYPE (parm) = t;
3766 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3768 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3770 /* PARM is a template template parameter. This is going to
3772 tree tparms, targs, innermost_args, t;
3775 /* First, fix up the parms of the template template parm
3776 because the parms are involved in defining the new canonical
3777 type of the template template parm. */
3779 /* So we need to substitute the template parm types that have
3780 been fixed up so far into the template parms of this template
3781 template parm. E.g, consider this:
3783 template<class T, template<T u> class TT> class S;
3785 In this case we want to substitute T into the
3786 template parameters of TT.
3788 So let's walk the template parms of PARM here, and
3789 tsubst ARGLIST into into each of the template
3792 /* For this substitution we need to build the full set of
3793 template parameters and use that as arguments for the
3794 tsubsting function. */
3795 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3797 /* This will contain the innermost parms of PARM into which
3798 we have substituted so far. */
3799 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3800 targs = add_to_template_args (arglist, innermost_args);
3801 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3805 parameter = TREE_VEC_ELT (tparms, j);
3807 /* INNERMOST_ARGS needs to have at least the same number
3808 of elements as the index PARAMETER, ortherwise
3809 tsubsting into PARAMETER will result in partially
3810 instantiating it, reducing its tempate parm
3811 level. Let's tactically fill INNERMOST_ARGS for that
3813 TREE_VEC_ELT (innermost_args, j) =
3814 template_parm_to_arg (parameter);
3816 fixup_template_parm (parameter, j,
3817 TREE_VEC_LENGTH (tparms),
3821 /* Now fix up the type of the template template parm. */
3823 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3824 TREE_TYPE (parm) = t;
3826 TREE_VEC_ELT (fixedup_args, idx) =
3827 template_parm_to_arg (parm_desc);
3829 else if (TREE_CODE (parm) == PARM_DECL)
3831 /* PARM is a non-type template parameter. We need to:
3833 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3834 proper number of sibling parameters.
3836 * Make lookups of the template parameter return a reference
3837 to the fixed-up index. No lookup should return references
3838 to the former index anymore.
3840 * Substitute the template parms that got fixed up so far
3842 * into the type of PARM. */
3844 tree index = DECL_INITIAL (parm);
3846 /* PUSHED_DECL is the decl added to the symbol table with
3847 the name of the parameter. E,g:
3849 template<class T, T u> //#0
3850 auto my_function(T t) -> decltype(u); //#1
3852 Here, when looking up u at //#1, we get the decl of u
3853 resulting from the declaration in #0. This is what
3854 PUSHED_DECL is. We need to replace the reference to the
3855 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3856 fixed-up TEMPLATE_PARM_INDEX. */
3857 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3859 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3860 fixup the type of PUSHED_DECL as well and luckily
3861 fixup_template_parm_index does it for us too. */
3862 tree fixed_up_index =
3863 fixup_template_parm_index (index, arglist, num_parms);
3865 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3867 /* Add this fixed up PARM to the template parms we've fixed
3868 up so far and use that to substitute the fixed-up
3869 template parms into the type of PARM. */
3870 TREE_VEC_ELT (fixedup_args, idx) =
3871 template_parm_to_arg (parm_desc);
3872 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3873 tf_none, NULL_TREE);
3876 TREE_PURPOSE (parm_desc) =
3877 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3878 arglist, tf_none, parm);
3880 pop_deferring_access_checks ();
3883 /* Walk the current template parms and properly compute the canonical
3884 types of the dependent types created during
3885 cp_parser_template_parameter_list. */
3888 fixup_template_parms (void)
3895 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3896 if (parameter_vec == NULL_TREE)
3899 num_parms = TREE_VEC_LENGTH (parameter_vec);
3901 /* This vector contains the current innermost template parms that
3902 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3903 to be passed to tsubst* functions as their ARGS argument. */
3904 fixedup_args = make_tree_vec (num_parms);
3906 /* This vector contains the full set of template parms in a form
3907 suitable to be passed to substs functions as their ARGS
3909 arglist = current_template_args ();
3910 arglist = add_outermost_template_args (arglist, fixedup_args);
3912 /* Let's do the proper fixup now. */
3913 for (i = 0; i < num_parms; ++i)
3914 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3915 i, num_parms, arglist);
3918 /* end_template_decl is called after a template declaration is seen. */
3921 end_template_decl (void)
3923 reset_specialization ();
3925 if (! processing_template_decl)
3928 /* This matches the pushlevel in begin_template_parm_list. */
3931 --processing_template_decl;
3932 current_template_parms = TREE_CHAIN (current_template_parms);
3935 /* Takes a TREE_LIST representing a template parameter and convert it
3936 into an argument suitable to be passed to the type substitution
3937 functions. Note that If the TREE_LIST contains an error_mark
3938 node, the returned argument is error_mark_node. */
3941 template_parm_to_arg (tree t)
3945 || TREE_CODE (t) != TREE_LIST)
3948 if (error_operand_p (TREE_VALUE (t)))
3949 return error_mark_node;
3953 if (TREE_CODE (t) == TYPE_DECL
3954 || TREE_CODE (t) == TEMPLATE_DECL)
3958 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3960 /* Turn this argument into a TYPE_ARGUMENT_PACK
3961 with a single element, which expands T. */
3962 tree vec = make_tree_vec (1);
3963 #ifdef ENABLE_CHECKING
3964 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3965 (vec, TREE_VEC_LENGTH (vec));
3967 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3969 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3970 SET_ARGUMENT_PACK_ARGS (t, vec);
3975 t = DECL_INITIAL (t);
3977 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3979 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3980 with a single element, which expands T. */
3981 tree vec = make_tree_vec (1);
3982 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3983 #ifdef ENABLE_CHECKING
3984 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3985 (vec, TREE_VEC_LENGTH (vec));
3987 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3989 t = make_node (NONTYPE_ARGUMENT_PACK);
3990 SET_ARGUMENT_PACK_ARGS (t, vec);
3991 TREE_TYPE (t) = type;
3997 /* Within the declaration of a template, return all levels of template
3998 parameters that apply. The template parameters are represented as
3999 a TREE_VEC, in the form documented in cp-tree.h for template
4003 current_template_args (void)
4006 tree args = NULL_TREE;
4007 int length = TMPL_PARMS_DEPTH (current_template_parms);
4010 /* If there is only one level of template parameters, we do not
4011 create a TREE_VEC of TREE_VECs. Instead, we return a single
4012 TREE_VEC containing the arguments. */
4014 args = make_tree_vec (length);
4016 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4018 tree a = copy_node (TREE_VALUE (header));
4021 TREE_TYPE (a) = NULL_TREE;
4022 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4023 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4025 #ifdef ENABLE_CHECKING
4026 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4030 TREE_VEC_ELT (args, --l) = a;
4035 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4036 /* This can happen for template parms of a template template
4039 template<template<class T, class U> class TT> struct S;
4041 Consider the level of the parms of TT; T and U both have
4042 level 2; TT has no template parm of level 1. So in this case
4043 the first element of full_template_args is NULL_TREE. If we
4044 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4045 of 2. This will make tsubst wrongly consider that T and U
4046 have level 1. Instead, let's create a dummy vector as the
4047 first element of full_template_args so that TMPL_ARG_DEPTH
4048 returns the correct depth for args. */
4049 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4053 /* Update the declared TYPE by doing any lookups which were thought to be
4054 dependent, but are not now that we know the SCOPE of the declarator. */
4057 maybe_update_decl_type (tree orig_type, tree scope)
4059 tree type = orig_type;
4061 if (type == NULL_TREE)
4064 if (TREE_CODE (orig_type) == TYPE_DECL)
4065 type = TREE_TYPE (type);
4067 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4068 && dependent_type_p (type)
4069 /* Don't bother building up the args in this case. */
4070 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4072 /* tsubst in the args corresponding to the template parameters,
4073 including auto if present. Most things will be unchanged, but
4074 make_typename_type and tsubst_qualified_id will resolve
4075 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4076 tree args = current_template_args ();
4077 tree auto_node = type_uses_auto (type);
4081 tree auto_vec = make_tree_vec (1);
4082 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4083 args = add_to_template_args (args, auto_vec);
4085 pushed = push_scope (scope);
4086 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4091 if (type == error_mark_node)
4094 if (TREE_CODE (orig_type) == TYPE_DECL)
4096 if (same_type_p (type, TREE_TYPE (orig_type)))
4099 type = TYPE_NAME (type);
4104 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4105 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4106 a member template. Used by push_template_decl below. */
4109 build_template_decl (tree decl, tree parms, bool member_template_p)
4111 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4112 DECL_TEMPLATE_PARMS (tmpl) = parms;
4113 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4114 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4119 struct template_parm_data
4121 /* The level of the template parameters we are currently
4125 /* The index of the specialization argument we are currently
4129 /* An array whose size is the number of template parameters. The
4130 elements are nonzero if the parameter has been used in any one
4131 of the arguments processed so far. */
4134 /* An array whose size is the number of template arguments. The
4135 elements are nonzero if the argument makes use of template
4136 parameters of this level. */
4137 int* arg_uses_template_parms;
4140 /* Subroutine of push_template_decl used to see if each template
4141 parameter in a partial specialization is used in the explicit
4142 argument list. If T is of the LEVEL given in DATA (which is
4143 treated as a template_parm_data*), then DATA->PARMS is marked
4147 mark_template_parm (tree t, void* data)
4151 struct template_parm_data* tpd = (struct template_parm_data*) data;
4153 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4155 level = TEMPLATE_PARM_LEVEL (t);
4156 idx = TEMPLATE_PARM_IDX (t);
4160 level = TEMPLATE_TYPE_LEVEL (t);
4161 idx = TEMPLATE_TYPE_IDX (t);
4164 if (level == tpd->level)
4166 tpd->parms[idx] = 1;
4167 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4170 /* Return zero so that for_each_template_parm will continue the
4171 traversal of the tree; we want to mark *every* template parm. */
4175 /* Process the partial specialization DECL. */
4178 process_partial_specialization (tree decl)
4180 tree type = TREE_TYPE (decl);
4181 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4182 tree specargs = CLASSTYPE_TI_ARGS (type);
4183 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4184 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4187 int nargs = TREE_VEC_LENGTH (inner_args);
4190 bool did_error_intro = false;
4191 struct template_parm_data tpd;
4192 struct template_parm_data tpd2;
4194 gcc_assert (current_template_parms);
4196 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4197 ntparms = TREE_VEC_LENGTH (inner_parms);
4199 /* We check that each of the template parameters given in the
4200 partial specialization is used in the argument list to the
4201 specialization. For example:
4203 template <class T> struct S;
4204 template <class T> struct S<T*>;
4206 The second declaration is OK because `T*' uses the template
4207 parameter T, whereas
4209 template <class T> struct S<int>;
4211 is no good. Even trickier is:
4222 The S2<T> declaration is actually invalid; it is a
4223 full-specialization. Of course,
4226 struct S2<T (*)(U)>;
4228 or some such would have been OK. */
4229 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4230 tpd.parms = XALLOCAVEC (int, ntparms);
4231 memset (tpd.parms, 0, sizeof (int) * ntparms);
4233 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4234 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4235 for (i = 0; i < nargs; ++i)
4237 tpd.current_arg = i;
4238 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4239 &mark_template_parm,
4242 /*include_nondeduced_p=*/false);
4244 for (i = 0; i < ntparms; ++i)
4245 if (tpd.parms[i] == 0)
4247 /* One of the template parms was not used in the
4249 if (!did_error_intro)
4251 error ("template parameters not used in partial specialization:");
4252 did_error_intro = true;
4255 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4258 if (did_error_intro)
4259 return error_mark_node;
4261 /* [temp.class.spec]
4263 The argument list of the specialization shall not be identical to
4264 the implicit argument list of the primary template. */
4265 if (comp_template_args
4267 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4269 error ("partial specialization %qT does not specialize any template arguments", type);
4271 /* [temp.class.spec]
4273 A partially specialized non-type argument expression shall not
4274 involve template parameters of the partial specialization except
4275 when the argument expression is a simple identifier.
4277 The type of a template parameter corresponding to a specialized
4278 non-type argument shall not be dependent on a parameter of the
4281 Also, we verify that pack expansions only occur at the
4282 end of the argument list. */
4283 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4285 for (i = 0; i < nargs; ++i)
4287 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4288 tree arg = TREE_VEC_ELT (inner_args, i);
4289 tree packed_args = NULL_TREE;
4292 if (ARGUMENT_PACK_P (arg))
4294 /* Extract the arguments from the argument pack. We'll be
4295 iterating over these in the following loop. */
4296 packed_args = ARGUMENT_PACK_ARGS (arg);
4297 len = TREE_VEC_LENGTH (packed_args);
4300 for (j = 0; j < len; j++)
4303 /* Get the Jth argument in the parameter pack. */
4304 arg = TREE_VEC_ELT (packed_args, j);
4306 if (PACK_EXPANSION_P (arg))
4308 /* Pack expansions must come at the end of the
4310 if ((packed_args && j < len - 1)
4311 || (!packed_args && i < nargs - 1))
4313 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4314 error ("parameter pack argument %qE must be at the "
4315 "end of the template argument list", arg);
4317 error ("parameter pack argument %qT must be at the "
4318 "end of the template argument list", arg);
4322 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4323 /* We only care about the pattern. */
4324 arg = PACK_EXPANSION_PATTERN (arg);
4326 if (/* These first two lines are the `non-type' bit. */
4328 && TREE_CODE (arg) != TEMPLATE_DECL
4329 /* This next line is the `argument expression is not just a
4330 simple identifier' condition and also the `specialized
4331 non-type argument' bit. */
4332 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4334 if ((!packed_args && tpd.arg_uses_template_parms[i])
4335 || (packed_args && uses_template_parms (arg)))
4336 error ("template argument %qE involves template parameter(s)",
4340 /* Look at the corresponding template parameter,
4341 marking which template parameters its type depends
4343 tree type = TREE_TYPE (parm);
4347 /* We haven't yet initialized TPD2. Do so now. */
4348 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4349 /* The number of parameters here is the number in the
4350 main template, which, as checked in the assertion
4352 tpd2.parms = XALLOCAVEC (int, nargs);
4354 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4357 /* Mark the template parameters. But this time, we're
4358 looking for the template parameters of the main
4359 template, not in the specialization. */
4360 tpd2.current_arg = i;
4361 tpd2.arg_uses_template_parms[i] = 0;
4362 memset (tpd2.parms, 0, sizeof (int) * nargs);
4363 for_each_template_parm (type,
4364 &mark_template_parm,
4367 /*include_nondeduced_p=*/false);
4369 if (tpd2.arg_uses_template_parms [i])
4371 /* The type depended on some template parameters.
4372 If they are fully specialized in the
4373 specialization, that's OK. */
4376 for (j = 0; j < nargs; ++j)
4377 if (tpd2.parms[j] != 0
4378 && tpd.arg_uses_template_parms [j])
4381 error_n (input_location, count,
4382 "type %qT of template argument %qE depends "
4383 "on a template parameter",
4384 "type %qT of template argument %qE depends "
4385 "on template parameters",
4394 /* We should only get here once. */
4395 gcc_assert (!COMPLETE_TYPE_P (type));
4397 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4398 = tree_cons (specargs, inner_parms,
4399 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4400 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4402 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4403 inst = TREE_CHAIN (inst))
4405 tree inst_type = TREE_VALUE (inst);
4406 if (COMPLETE_TYPE_P (inst_type)
4407 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4409 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4410 if (spec && TREE_TYPE (spec) == type)
4411 permerror (input_location,
4412 "partial specialization of %qT after instantiation "
4413 "of %qT", type, inst_type);
4420 /* Check that a template declaration's use of default arguments and
4421 parameter packs is not invalid. Here, PARMS are the template
4422 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4423 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4427 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4428 declaration (but not a definition); 1 indicates a declaration, 2
4429 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4430 emitted for extraneous default arguments.
4432 Returns TRUE if there were no errors found, FALSE otherwise. */
4435 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4436 int is_partial, int is_friend_decl)
4439 int last_level_to_check;
4441 bool no_errors = true;
4445 A default template-argument shall not be specified in a
4446 function template declaration or a function template definition, nor
4447 in the template-parameter-list of the definition of a member of a
4450 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4451 /* You can't have a function template declaration in a local
4452 scope, nor you can you define a member of a class template in a
4456 if (current_class_type
4457 && !TYPE_BEING_DEFINED (current_class_type)
4458 && DECL_LANG_SPECIFIC (decl)
4459 && DECL_DECLARES_FUNCTION_P (decl)
4460 /* If this is either a friend defined in the scope of the class
4461 or a member function. */
4462 && (DECL_FUNCTION_MEMBER_P (decl)
4463 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4464 : DECL_FRIEND_CONTEXT (decl)
4465 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4467 /* And, if it was a member function, it really was defined in
4468 the scope of the class. */
4469 && (!DECL_FUNCTION_MEMBER_P (decl)
4470 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4471 /* We already checked these parameters when the template was
4472 declared, so there's no need to do it again now. This function
4473 was defined in class scope, but we're processing it's body now
4474 that the class is complete. */
4477 /* Core issue 226 (C++0x only): the following only applies to class
4479 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4483 If a template-parameter has a default template-argument, all
4484 subsequent template-parameters shall have a default
4485 template-argument supplied. */
4486 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4488 tree inner_parms = TREE_VALUE (parm_level);
4489 int ntparms = TREE_VEC_LENGTH (inner_parms);
4490 int seen_def_arg_p = 0;
4493 for (i = 0; i < ntparms; ++i)
4495 tree parm = TREE_VEC_ELT (inner_parms, i);
4497 if (parm == error_mark_node)
4500 if (TREE_PURPOSE (parm))
4502 else if (seen_def_arg_p
4503 && !template_parameter_pack_p (TREE_VALUE (parm)))
4505 error ("no default argument for %qD", TREE_VALUE (parm));
4506 /* For better subsequent error-recovery, we indicate that
4507 there should have been a default argument. */
4508 TREE_PURPOSE (parm) = error_mark_node;
4514 /* Don't complain about an enclosing partial
4516 && parm_level == parms
4517 && TREE_CODE (decl) == TYPE_DECL
4519 && template_parameter_pack_p (TREE_VALUE (parm)))
4521 /* A primary class template can only have one
4522 parameter pack, at the end of the template
4525 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4526 error ("parameter pack %qE must be at the end of the"
4527 " template parameter list", TREE_VALUE (parm));
4529 error ("parameter pack %qT must be at the end of the"
4530 " template parameter list",
4531 TREE_TYPE (TREE_VALUE (parm)));
4533 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4541 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4545 /* For an ordinary class template, default template arguments are
4546 allowed at the innermost level, e.g.:
4547 template <class T = int>
4549 but, in a partial specialization, they're not allowed even
4550 there, as we have in [temp.class.spec]:
4552 The template parameter list of a specialization shall not
4553 contain default template argument values.
4555 So, for a partial specialization, or for a function template
4556 (in C++98/C++03), we look at all of them. */
4559 /* But, for a primary class template that is not a partial
4560 specialization we look at all template parameters except the
4562 parms = TREE_CHAIN (parms);
4564 /* Figure out what error message to issue. */
4565 if (is_friend_decl == 2)
4566 msg = G_("default template arguments may not be used in function template "
4567 "friend re-declaration");
4568 else if (is_friend_decl)
4569 msg = G_("default template arguments may not be used in function template "
4570 "friend declarations");
4571 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4572 msg = G_("default template arguments may not be used in function templates "
4573 "without -std=c++0x or -std=gnu++0x");
4574 else if (is_partial)
4575 msg = G_("default template arguments may not be used in "
4576 "partial specializations");
4578 msg = G_("default argument for template parameter for class enclosing %qD");
4580 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4581 /* If we're inside a class definition, there's no need to
4582 examine the parameters to the class itself. On the one
4583 hand, they will be checked when the class is defined, and,
4584 on the other, default arguments are valid in things like:
4585 template <class T = double>
4586 struct S { template <class U> void f(U); };
4587 Here the default argument for `S' has no bearing on the
4588 declaration of `f'. */
4589 last_level_to_check = template_class_depth (current_class_type) + 1;
4591 /* Check everything. */
4592 last_level_to_check = 0;
4594 for (parm_level = parms;
4595 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4596 parm_level = TREE_CHAIN (parm_level))
4598 tree inner_parms = TREE_VALUE (parm_level);
4602 ntparms = TREE_VEC_LENGTH (inner_parms);
4603 for (i = 0; i < ntparms; ++i)
4605 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4608 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4613 if (is_friend_decl == 2)
4620 /* Clear out the default argument so that we are not
4622 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4626 /* At this point, if we're still interested in issuing messages,
4627 they must apply to classes surrounding the object declared. */
4629 msg = G_("default argument for template parameter for class "
4636 /* Worker for push_template_decl_real, called via
4637 for_each_template_parm. DATA is really an int, indicating the
4638 level of the parameters we are interested in. If T is a template
4639 parameter of that level, return nonzero. */
4642 template_parm_this_level_p (tree t, void* data)
4644 int this_level = *(int *)data;
4647 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4648 level = TEMPLATE_PARM_LEVEL (t);
4650 level = TEMPLATE_TYPE_LEVEL (t);
4651 return level == this_level;
4654 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4655 parameters given by current_template_args, or reuses a
4656 previously existing one, if appropriate. Returns the DECL, or an
4657 equivalent one, if it is replaced via a call to duplicate_decls.
4659 If IS_FRIEND is true, DECL is a friend declaration. */
4662 push_template_decl_real (tree decl, bool is_friend)
4670 int new_template_p = 0;
4671 /* True if the template is a member template, in the sense of
4673 bool member_template_p = false;
4675 if (decl == error_mark_node || !current_template_parms)
4676 return error_mark_node;
4678 /* See if this is a partial specialization. */
4679 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4680 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4681 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4683 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4687 /* For a friend, we want the context of the friend function, not
4688 the type of which it is a friend. */
4689 ctx = CP_DECL_CONTEXT (decl);
4690 else if (CP_DECL_CONTEXT (decl)
4691 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4692 /* In the case of a virtual function, we want the class in which
4694 ctx = CP_DECL_CONTEXT (decl);
4696 /* Otherwise, if we're currently defining some class, the DECL
4697 is assumed to be a member of the class. */
4698 ctx = current_scope ();
4700 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4703 if (!DECL_CONTEXT (decl))
4704 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4706 /* See if this is a primary template. */
4707 if (is_friend && ctx)
4708 /* A friend template that specifies a class context, i.e.
4709 template <typename T> friend void A<T>::f();
4713 primary = template_parm_scope_p ();
4717 if (DECL_CLASS_SCOPE_P (decl))
4718 member_template_p = true;
4719 if (TREE_CODE (decl) == TYPE_DECL
4720 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4722 error ("template class without a name");
4723 return error_mark_node;
4725 else if (TREE_CODE (decl) == FUNCTION_DECL)
4727 if (DECL_DESTRUCTOR_P (decl))
4731 A destructor shall not be a member template. */
4732 error ("destructor %qD declared as member template", decl);
4733 return error_mark_node;
4735 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4736 && (!prototype_p (TREE_TYPE (decl))
4737 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4738 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4739 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4740 == void_list_node)))
4742 /* [basic.stc.dynamic.allocation]
4744 An allocation function can be a function
4745 template. ... Template allocation functions shall
4746 have two or more parameters. */
4747 error ("invalid template declaration of %qD", decl);
4748 return error_mark_node;
4751 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4752 && CLASS_TYPE_P (TREE_TYPE (decl)))
4756 error ("template declaration of %q#D", decl);
4757 return error_mark_node;
4761 /* Check to see that the rules regarding the use of default
4762 arguments are not being violated. */
4763 check_default_tmpl_args (decl, current_template_parms,
4764 primary, is_partial, /*is_friend_decl=*/0);
4766 /* Ensure that there are no parameter packs in the type of this
4767 declaration that have not been expanded. */
4768 if (TREE_CODE (decl) == FUNCTION_DECL)
4770 /* Check each of the arguments individually to see if there are
4771 any bare parameter packs. */
4772 tree type = TREE_TYPE (decl);
4773 tree arg = DECL_ARGUMENTS (decl);
4774 tree argtype = TYPE_ARG_TYPES (type);
4776 while (arg && argtype)
4778 if (!FUNCTION_PARAMETER_PACK_P (arg)
4779 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4781 /* This is a PARM_DECL that contains unexpanded parameter
4782 packs. We have already complained about this in the
4783 check_for_bare_parameter_packs call, so just replace
4784 these types with ERROR_MARK_NODE. */
4785 TREE_TYPE (arg) = error_mark_node;
4786 TREE_VALUE (argtype) = error_mark_node;
4789 arg = DECL_CHAIN (arg);
4790 argtype = TREE_CHAIN (argtype);
4793 /* Check for bare parameter packs in the return type and the
4794 exception specifiers. */
4795 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4796 /* Errors were already issued, set return type to int
4797 as the frontend doesn't expect error_mark_node as
4799 TREE_TYPE (type) = integer_type_node;
4800 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4801 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4803 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4805 TREE_TYPE (decl) = error_mark_node;
4806 return error_mark_node;
4810 return process_partial_specialization (decl);
4812 args = current_template_args ();
4815 || TREE_CODE (ctx) == FUNCTION_DECL
4816 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4817 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4819 if (DECL_LANG_SPECIFIC (decl)
4820 && DECL_TEMPLATE_INFO (decl)
4821 && DECL_TI_TEMPLATE (decl))
4822 tmpl = DECL_TI_TEMPLATE (decl);
4823 /* If DECL is a TYPE_DECL for a class-template, then there won't
4824 be DECL_LANG_SPECIFIC. The information equivalent to
4825 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4826 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4827 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4828 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4830 /* Since a template declaration already existed for this
4831 class-type, we must be redeclaring it here. Make sure
4832 that the redeclaration is valid. */
4833 redeclare_class_template (TREE_TYPE (decl),
4834 current_template_parms);
4835 /* We don't need to create a new TEMPLATE_DECL; just use the
4836 one we already had. */
4837 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4841 tmpl = build_template_decl (decl, current_template_parms,
4845 if (DECL_LANG_SPECIFIC (decl)
4846 && DECL_TEMPLATE_SPECIALIZATION (decl))
4848 /* A specialization of a member template of a template
4850 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4851 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4852 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4858 tree a, t, current, parms;
4860 tree tinfo = get_template_info (decl);
4864 error ("template definition of non-template %q#D", decl);
4865 return error_mark_node;
4868 tmpl = TI_TEMPLATE (tinfo);
4870 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4871 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4872 && DECL_TEMPLATE_SPECIALIZATION (decl)
4873 && DECL_MEMBER_TEMPLATE_P (tmpl))
4877 /* The declaration is a specialization of a member
4878 template, declared outside the class. Therefore, the
4879 innermost template arguments will be NULL, so we
4880 replace them with the arguments determined by the
4881 earlier call to check_explicit_specialization. */
4882 args = DECL_TI_ARGS (decl);
4885 = build_template_decl (decl, current_template_parms,
4887 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4888 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4889 DECL_TI_TEMPLATE (decl) = new_tmpl;
4890 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4891 DECL_TEMPLATE_INFO (new_tmpl)
4892 = build_template_info (tmpl, args);
4894 register_specialization (new_tmpl,
4895 most_general_template (tmpl),
4901 /* Make sure the template headers we got make sense. */
4903 parms = DECL_TEMPLATE_PARMS (tmpl);
4904 i = TMPL_PARMS_DEPTH (parms);
4905 if (TMPL_ARGS_DEPTH (args) != i)
4907 error ("expected %d levels of template parms for %q#D, got %d",
4908 i, decl, TMPL_ARGS_DEPTH (args));
4911 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4913 a = TMPL_ARGS_LEVEL (args, i);
4914 t = INNERMOST_TEMPLATE_PARMS (parms);
4916 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4918 if (current == decl)
4919 error ("got %d template parameters for %q#D",
4920 TREE_VEC_LENGTH (a), decl);
4922 error ("got %d template parameters for %q#T",
4923 TREE_VEC_LENGTH (a), current);
4924 error (" but %d required", TREE_VEC_LENGTH (t));
4925 return error_mark_node;
4928 if (current == decl)
4930 else if (current == NULL_TREE)
4931 /* Can happen in erroneous input. */
4934 current = (TYPE_P (current)
4935 ? TYPE_CONTEXT (current)
4936 : DECL_CONTEXT (current));
4939 /* Check that the parms are used in the appropriate qualifying scopes
4940 in the declarator. */
4941 if (!comp_template_args
4943 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4946 template arguments to %qD do not match original template %qD",
4947 decl, DECL_TEMPLATE_RESULT (tmpl));
4948 if (!uses_template_parms (TI_ARGS (tinfo)))
4949 inform (input_location, "use template<> for an explicit specialization");
4950 /* Avoid crash in import_export_decl. */
4951 DECL_INTERFACE_KNOWN (decl) = 1;
4952 return error_mark_node;
4956 DECL_TEMPLATE_RESULT (tmpl) = decl;
4957 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4959 /* Push template declarations for global functions and types. Note
4960 that we do not try to push a global template friend declared in a
4961 template class; such a thing may well depend on the template
4962 parameters of the class. */
4963 if (new_template_p && !ctx
4964 && !(is_friend && template_class_depth (current_class_type) > 0))
4966 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4967 if (tmpl == error_mark_node)
4968 return error_mark_node;
4970 /* Hide template friend classes that haven't been declared yet. */
4971 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4973 DECL_ANTICIPATED (tmpl) = 1;
4974 DECL_FRIEND_P (tmpl) = 1;
4980 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4983 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4984 if (DECL_CONV_FN_P (tmpl))
4986 int depth = TMPL_PARMS_DEPTH (parms);
4988 /* It is a conversion operator. See if the type converted to
4989 depends on innermost template operands. */
4991 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4993 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4996 /* Give template template parms a DECL_CONTEXT of the template
4997 for which they are a parameter. */
4998 parms = INNERMOST_TEMPLATE_PARMS (parms);
4999 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5001 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5002 if (TREE_CODE (parm) == TEMPLATE_DECL)
5003 DECL_CONTEXT (parm) = tmpl;
5007 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5008 back to its most general template. If TMPL is a specialization,
5009 ARGS may only have the innermost set of arguments. Add the missing
5010 argument levels if necessary. */
5011 if (DECL_TEMPLATE_INFO (tmpl))
5012 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5014 info = build_template_info (tmpl, args);
5016 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5017 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5018 else if (DECL_LANG_SPECIFIC (decl))
5019 DECL_TEMPLATE_INFO (decl) = info;
5021 return DECL_TEMPLATE_RESULT (tmpl);
5025 push_template_decl (tree decl)
5027 return push_template_decl_real (decl, false);
5030 /* Called when a class template TYPE is redeclared with the indicated
5031 template PARMS, e.g.:
5033 template <class T> struct S;
5034 template <class T> struct S {}; */
5037 redeclare_class_template (tree type, tree parms)
5043 if (!TYPE_TEMPLATE_INFO (type))
5045 error ("%qT is not a template type", type);
5049 tmpl = TYPE_TI_TEMPLATE (type);
5050 if (!PRIMARY_TEMPLATE_P (tmpl))
5051 /* The type is nested in some template class. Nothing to worry
5052 about here; there are no new template parameters for the nested
5058 error ("template specifiers not specified in declaration of %qD",
5063 parms = INNERMOST_TEMPLATE_PARMS (parms);
5064 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5066 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5068 error_n (input_location, TREE_VEC_LENGTH (parms),
5069 "redeclared with %d template parameter",
5070 "redeclared with %d template parameters",
5071 TREE_VEC_LENGTH (parms));
5072 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5073 "previous declaration %q+D used %d template parameter",
5074 "previous declaration %q+D used %d template parameters",
5075 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5079 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5086 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5087 || TREE_VEC_ELT (parms, i) == error_mark_node)
5090 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5091 if (tmpl_parm == error_mark_node)
5094 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5095 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5096 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5098 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5100 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5101 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5102 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5103 || (TREE_CODE (tmpl_parm) != PARM_DECL
5104 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5105 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5106 || (TREE_CODE (tmpl_parm) == PARM_DECL
5107 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5108 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5110 error ("template parameter %q+#D", tmpl_parm);
5111 error ("redeclared here as %q#D", parm);
5115 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5117 /* We have in [temp.param]:
5119 A template-parameter may not be given default arguments
5120 by two different declarations in the same scope. */
5121 error_at (input_location, "redefinition of default argument for %q#D", parm);
5122 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5123 "original definition appeared here");
5127 if (parm_default != NULL_TREE)
5128 /* Update the previous template parameters (which are the ones
5129 that will really count) with the new default value. */
5130 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5131 else if (tmpl_default != NULL_TREE)
5132 /* Update the new parameters, too; they'll be used as the
5133 parameters for any members. */
5134 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5140 /* Simplify EXPR if it is a non-dependent expression. Returns the
5141 (possibly simplified) expression. */
5144 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5146 if (expr == NULL_TREE)
5149 /* If we're in a template, but EXPR isn't value dependent, simplify
5150 it. We're supposed to treat:
5152 template <typename T> void f(T[1 + 1]);
5153 template <typename T> void f(T[2]);
5155 as two declarations of the same function, for example. */
5156 if (processing_template_decl
5157 && !type_dependent_expression_p (expr)
5158 && potential_constant_expression (expr)
5159 && !value_dependent_expression_p (expr))
5161 HOST_WIDE_INT saved_processing_template_decl;
5163 saved_processing_template_decl = processing_template_decl;
5164 processing_template_decl = 0;
5165 expr = tsubst_copy_and_build (expr,
5168 /*in_decl=*/NULL_TREE,
5169 /*function_p=*/false,
5170 /*integral_constant_expression_p=*/true);
5171 processing_template_decl = saved_processing_template_decl;
5177 fold_non_dependent_expr (tree expr)
5179 return fold_non_dependent_expr_sfinae (expr, tf_error);
5182 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5183 must be a function or a pointer-to-function type, as specified
5184 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5185 and check that the resulting function has external linkage. */
5188 convert_nontype_argument_function (tree type, tree expr)
5193 fn = instantiate_type (type, fns, tf_none);
5194 if (fn == error_mark_node)
5195 return error_mark_node;
5198 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5199 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5200 if (TREE_CODE (fn_no_ptr) == BASELINK)
5201 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5203 /* [temp.arg.nontype]/1
5205 A template-argument for a non-type, non-template template-parameter
5208 -- the address of an object or function with external linkage. */
5209 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5211 error ("%qE is not a valid template argument for type %qT "
5212 "because function %qD has not external linkage",
5213 expr, type, fn_no_ptr);
5220 /* Subroutine of convert_nontype_argument.
5221 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5222 Emit an error otherwise. */
5225 check_valid_ptrmem_cst_expr (tree type, tree expr,
5226 tsubst_flags_t complain)
5229 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5231 if (complain & tf_error)
5233 error ("%qE is not a valid template argument for type %qT",
5235 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5240 /* Returns TRUE iff the address of OP is value-dependent.
5242 14.6.2.4 [temp.dep.temp]:
5243 A non-integral non-type template-argument is dependent if its type is
5244 dependent or it has either of the following forms
5247 and contains a nested-name-specifier which specifies a class-name that
5248 names a dependent type.
5250 We generalize this to just say that the address of a member of a
5251 dependent class is value-dependent; the above doesn't cover the
5252 address of a static data member named with an unqualified-id. */
5255 has_value_dependent_address (tree op)
5257 /* We could use get_inner_reference here, but there's no need;
5258 this is only relevant for template non-type arguments, which
5259 can only be expressed as &id-expression. */
5262 tree ctx = CP_DECL_CONTEXT (op);
5263 if (TYPE_P (ctx) && dependent_type_p (ctx))
5270 /* Attempt to convert the non-type template parameter EXPR to the
5271 indicated TYPE. If the conversion is successful, return the
5272 converted value. If the conversion is unsuccessful, return
5273 NULL_TREE if we issued an error message, or error_mark_node if we
5274 did not. We issue error messages for out-and-out bad template
5275 parameters, but not simply because the conversion failed, since we
5276 might be just trying to do argument deduction. Both TYPE and EXPR
5277 must be non-dependent.
5279 The conversion follows the special rules described in
5280 [temp.arg.nontype], and it is much more strict than an implicit
5283 This function is called twice for each template argument (see
5284 lookup_template_class for a more accurate description of this
5285 problem). This means that we need to handle expressions which
5286 are not valid in a C++ source, but can be created from the
5287 first call (for instance, casts to perform conversions). These
5288 hacks can go away after we fix the double coercion problem. */
5291 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5295 /* Detect immediately string literals as invalid non-type argument.
5296 This special-case is not needed for correctness (we would easily
5297 catch this later), but only to provide better diagnostic for this
5298 common user mistake. As suggested by DR 100, we do not mention
5299 linkage issues in the diagnostic as this is not the point. */
5300 /* FIXME we're making this OK. */
5301 if (TREE_CODE (expr) == STRING_CST)
5303 if (complain & tf_error)
5304 error ("%qE is not a valid template argument for type %qT "
5305 "because string literals can never be used in this context",
5310 /* Add the ADDR_EXPR now for the benefit of
5311 value_dependent_expression_p. */
5312 if (TYPE_PTROBV_P (type)
5313 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5314 expr = decay_conversion (expr);
5316 /* If we are in a template, EXPR may be non-dependent, but still
5317 have a syntactic, rather than semantic, form. For example, EXPR
5318 might be a SCOPE_REF, rather than the VAR_DECL to which the
5319 SCOPE_REF refers. Preserving the qualifying scope is necessary
5320 so that access checking can be performed when the template is
5321 instantiated -- but here we need the resolved form so that we can
5322 convert the argument. */
5323 if (TYPE_REF_OBJ_P (type)
5324 && has_value_dependent_address (expr))
5325 /* If we want the address and it's value-dependent, don't fold. */;
5326 else if (!type_unknown_p (expr))
5327 expr = fold_non_dependent_expr_sfinae (expr, complain);
5328 if (error_operand_p (expr))
5329 return error_mark_node;
5330 expr_type = TREE_TYPE (expr);
5331 if (TREE_CODE (type) == REFERENCE_TYPE)
5332 expr = mark_lvalue_use (expr);
5334 expr = mark_rvalue_use (expr);
5336 /* HACK: Due to double coercion, we can get a
5337 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5338 which is the tree that we built on the first call (see
5339 below when coercing to reference to object or to reference to
5340 function). We just strip everything and get to the arg.
5341 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5343 if (TREE_CODE (expr) == NOP_EXPR)
5345 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5347 /* ??? Maybe we could use convert_from_reference here, but we
5348 would need to relax its constraints because the NOP_EXPR
5349 could actually change the type to something more cv-qualified,
5350 and this is not folded by convert_from_reference. */
5351 tree addr = TREE_OPERAND (expr, 0);
5352 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
5353 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5354 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5355 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5356 (TREE_TYPE (expr_type),
5357 TREE_TYPE (TREE_TYPE (addr))));
5359 expr = TREE_OPERAND (addr, 0);
5360 expr_type = TREE_TYPE (expr);
5363 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5364 parameter is a pointer to object, through decay and
5365 qualification conversion. Let's strip everything. */
5366 else if (TYPE_PTROBV_P (type))
5369 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5370 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5371 /* Skip the ADDR_EXPR only if it is part of the decay for
5372 an array. Otherwise, it is part of the original argument
5373 in the source code. */
5374 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5375 expr = TREE_OPERAND (expr, 0);
5376 expr_type = TREE_TYPE (expr);
5380 /* [temp.arg.nontype]/5, bullet 1
5382 For a non-type template-parameter of integral or enumeration type,
5383 integral promotions (_conv.prom_) and integral conversions
5384 (_conv.integral_) are applied. */
5385 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5387 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5388 t = maybe_constant_value (t);
5389 if (t != error_mark_node)
5392 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5393 return error_mark_node;
5395 /* Notice that there are constant expressions like '4 % 0' which
5396 do not fold into integer constants. */
5397 if (TREE_CODE (expr) != INTEGER_CST)
5399 if (complain & tf_error)
5401 int errs = errorcount, warns = warningcount;
5402 expr = cxx_constant_value (expr);
5403 if (errorcount > errs || warningcount > warns)
5404 inform (EXPR_LOC_OR_HERE (expr),
5405 "in template argument for type %qT ", type);
5406 if (expr == error_mark_node)
5408 /* else cxx_constant_value complained but gave us
5409 a real constant, so go ahead. */
5410 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5416 /* [temp.arg.nontype]/5, bullet 2
5418 For a non-type template-parameter of type pointer to object,
5419 qualification conversions (_conv.qual_) and the array-to-pointer
5420 conversion (_conv.array_) are applied. */
5421 else if (TYPE_PTROBV_P (type))
5423 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5425 A template-argument for a non-type, non-template template-parameter
5426 shall be one of: [...]
5428 -- the name of a non-type template-parameter;
5429 -- the address of an object or function with external linkage, [...]
5430 expressed as "& id-expression" where the & is optional if the name
5431 refers to a function or array, or if the corresponding
5432 template-parameter is a reference.
5434 Here, we do not care about functions, as they are invalid anyway
5435 for a parameter of type pointer-to-object. */
5437 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5438 /* Non-type template parameters are OK. */
5440 else if (TREE_CODE (expr) != ADDR_EXPR
5441 && TREE_CODE (expr_type) != ARRAY_TYPE)
5443 if (TREE_CODE (expr) == VAR_DECL)
5445 error ("%qD is not a valid template argument "
5446 "because %qD is a variable, not the address of "
5451 /* Other values, like integer constants, might be valid
5452 non-type arguments of some other type. */
5453 return error_mark_node;
5459 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5460 ? TREE_OPERAND (expr, 0) : expr);
5461 if (TREE_CODE (decl) != VAR_DECL)
5463 error ("%qE is not a valid template argument of type %qT "
5464 "because %qE is not a variable",
5468 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5470 error ("%qE is not a valid template argument of type %qT "
5471 "because %qD does not have external linkage",
5477 expr = decay_conversion (expr);
5478 if (expr == error_mark_node)
5479 return error_mark_node;
5481 expr = perform_qualification_conversions (type, expr);
5482 if (expr == error_mark_node)
5483 return error_mark_node;
5485 /* [temp.arg.nontype]/5, bullet 3
5487 For a non-type template-parameter of type reference to object, no
5488 conversions apply. The type referred to by the reference may be more
5489 cv-qualified than the (otherwise identical) type of the
5490 template-argument. The template-parameter is bound directly to the
5491 template-argument, which must be an lvalue. */
5492 else if (TYPE_REF_OBJ_P (type))
5494 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5496 return error_mark_node;
5498 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5500 error ("%qE is not a valid template argument for type %qT "
5501 "because of conflicts in cv-qualification", expr, type);
5505 if (!real_lvalue_p (expr))
5507 error ("%qE is not a valid template argument for type %qT "
5508 "because it is not an lvalue", expr, type);
5512 /* [temp.arg.nontype]/1
5514 A template-argument for a non-type, non-template template-parameter
5515 shall be one of: [...]
5517 -- the address of an object or function with external linkage. */
5518 if (TREE_CODE (expr) == INDIRECT_REF
5519 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5521 expr = TREE_OPERAND (expr, 0);
5524 error ("%q#D is not a valid template argument for type %qT "
5525 "because a reference variable does not have a constant "
5526 "address", expr, type);
5533 error ("%qE is not a valid template argument for type %qT "
5534 "because it is not an object with external linkage",
5539 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5541 error ("%qE is not a valid template argument for type %qT "
5542 "because object %qD has not external linkage",
5547 expr = build_nop (type, build_address (expr));
5549 /* [temp.arg.nontype]/5, bullet 4
5551 For a non-type template-parameter of type pointer to function, only
5552 the function-to-pointer conversion (_conv.func_) is applied. If the
5553 template-argument represents a set of overloaded functions (or a
5554 pointer to such), the matching function is selected from the set
5556 else if (TYPE_PTRFN_P (type))
5558 /* If the argument is a template-id, we might not have enough
5559 context information to decay the pointer. */
5560 if (!type_unknown_p (expr_type))
5562 expr = decay_conversion (expr);
5563 if (expr == error_mark_node)
5564 return error_mark_node;
5567 expr = convert_nontype_argument_function (type, expr);
5568 if (!expr || expr == error_mark_node)
5571 if (TREE_CODE (expr) != ADDR_EXPR)
5573 error ("%qE is not a valid template argument for type %qT", expr, type);
5574 error ("it must be the address of a function with external linkage");
5578 /* [temp.arg.nontype]/5, bullet 5
5580 For a non-type template-parameter of type reference to function, no
5581 conversions apply. If the template-argument represents a set of
5582 overloaded functions, the matching function is selected from the set
5584 else if (TYPE_REFFN_P (type))
5586 if (TREE_CODE (expr) == ADDR_EXPR)
5588 error ("%qE is not a valid template argument for type %qT "
5589 "because it is a pointer", expr, type);
5590 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5594 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5595 if (!expr || expr == error_mark_node)
5598 expr = build_nop (type, build_address (expr));
5600 /* [temp.arg.nontype]/5, bullet 6
5602 For a non-type template-parameter of type pointer to member function,
5603 no conversions apply. If the template-argument represents a set of
5604 overloaded member functions, the matching member function is selected
5605 from the set (_over.over_). */
5606 else if (TYPE_PTRMEMFUNC_P (type))
5608 expr = instantiate_type (type, expr, tf_none);
5609 if (expr == error_mark_node)
5610 return error_mark_node;
5612 /* [temp.arg.nontype] bullet 1 says the pointer to member
5613 expression must be a pointer-to-member constant. */
5614 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5615 return error_mark_node;
5617 /* There is no way to disable standard conversions in
5618 resolve_address_of_overloaded_function (called by
5619 instantiate_type). It is possible that the call succeeded by
5620 converting &B::I to &D::I (where B is a base of D), so we need
5621 to reject this conversion here.
5623 Actually, even if there was a way to disable standard conversions,
5624 it would still be better to reject them here so that we can
5625 provide a superior diagnostic. */
5626 if (!same_type_p (TREE_TYPE (expr), type))
5628 error ("%qE is not a valid template argument for type %qT "
5629 "because it is of type %qT", expr, type,
5631 /* If we are just one standard conversion off, explain. */
5632 if (can_convert (type, TREE_TYPE (expr)))
5633 inform (input_location,
5634 "standard conversions are not allowed in this context");
5638 /* [temp.arg.nontype]/5, bullet 7
5640 For a non-type template-parameter of type pointer to data member,
5641 qualification conversions (_conv.qual_) are applied. */
5642 else if (TYPE_PTRMEM_P (type))
5644 /* [temp.arg.nontype] bullet 1 says the pointer to member
5645 expression must be a pointer-to-member constant. */
5646 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5647 return error_mark_node;
5649 expr = perform_qualification_conversions (type, expr);
5650 if (expr == error_mark_node)
5653 /* A template non-type parameter must be one of the above. */
5657 /* Sanity check: did we actually convert the argument to the
5659 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5660 (type, TREE_TYPE (expr)));
5664 /* Subroutine of coerce_template_template_parms, which returns 1 if
5665 PARM_PARM and ARG_PARM match using the rule for the template
5666 parameters of template template parameters. Both PARM and ARG are
5667 template parameters; the rest of the arguments are the same as for
5668 coerce_template_template_parms.
5671 coerce_template_template_parm (tree parm,
5673 tsubst_flags_t complain,
5677 if (arg == NULL_TREE || arg == error_mark_node
5678 || parm == NULL_TREE || parm == error_mark_node)
5681 if (TREE_CODE (arg) != TREE_CODE (parm))
5684 switch (TREE_CODE (parm))
5687 /* We encounter instantiations of templates like
5688 template <template <template <class> class> class TT>
5691 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5692 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5694 if (!coerce_template_template_parms
5695 (parmparm, argparm, complain, in_decl, outer_args))
5701 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5702 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5703 /* Argument is a parameter pack but parameter is not. */
5708 /* The tsubst call is used to handle cases such as
5710 template <int> class C {};
5711 template <class T, template <T> class TT> class D {};
5714 i.e. the parameter list of TT depends on earlier parameters. */
5715 if (!uses_template_parms (TREE_TYPE (arg))
5717 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5721 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5722 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5723 /* Argument is a parameter pack but parameter is not. */
5736 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5737 template template parameters. Both PARM_PARMS and ARG_PARMS are
5738 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5741 Consider the example:
5742 template <class T> class A;
5743 template<template <class U> class TT> class B;
5745 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5746 the parameters to A, and OUTER_ARGS contains A. */
5749 coerce_template_template_parms (tree parm_parms,
5751 tsubst_flags_t complain,
5755 int nparms, nargs, i;
5759 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5760 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5762 nparms = TREE_VEC_LENGTH (parm_parms);
5763 nargs = TREE_VEC_LENGTH (arg_parms);
5765 /* Determine whether we have a parameter pack at the end of the
5766 template template parameter's template parameter list. */
5767 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5769 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5771 if (parm == error_mark_node)
5774 switch (TREE_CODE (parm))
5778 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5783 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5793 && !(variadic_p && nargs >= nparms - 1))
5796 /* Check all of the template parameters except the parameter pack at
5797 the end (if any). */
5798 for (i = 0; i < nparms - variadic_p; ++i)
5800 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5801 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5804 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5805 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5807 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5815 /* Check each of the template parameters in the template
5816 argument against the template parameter pack at the end of
5817 the template template parameter. */
5818 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5821 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5823 for (; i < nargs; ++i)
5825 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5828 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5830 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5839 /* Verifies that the deduced template arguments (in TARGS) for the
5840 template template parameters (in TPARMS) represent valid bindings,
5841 by comparing the template parameter list of each template argument
5842 to the template parameter list of its corresponding template
5843 template parameter, in accordance with DR150. This
5844 routine can only be called after all template arguments have been
5845 deduced. It will return TRUE if all of the template template
5846 parameter bindings are okay, FALSE otherwise. */
5848 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5850 int i, ntparms = TREE_VEC_LENGTH (tparms);
5853 /* We're dealing with template parms in this process. */
5854 ++processing_template_decl;
5856 targs = INNERMOST_TEMPLATE_ARGS (targs);
5858 for (i = 0; i < ntparms; ++i)
5860 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5861 tree targ = TREE_VEC_ELT (targs, i);
5863 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5865 tree packed_args = NULL_TREE;
5868 if (ARGUMENT_PACK_P (targ))
5870 /* Look inside the argument pack. */
5871 packed_args = ARGUMENT_PACK_ARGS (targ);
5872 len = TREE_VEC_LENGTH (packed_args);
5875 for (idx = 0; idx < len; ++idx)
5877 tree targ_parms = NULL_TREE;
5880 /* Extract the next argument from the argument
5882 targ = TREE_VEC_ELT (packed_args, idx);
5884 if (PACK_EXPANSION_P (targ))
5885 /* Look at the pattern of the pack expansion. */
5886 targ = PACK_EXPANSION_PATTERN (targ);
5888 /* Extract the template parameters from the template
5890 if (TREE_CODE (targ) == TEMPLATE_DECL)
5891 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5892 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5893 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5895 /* Verify that we can coerce the template template
5896 parameters from the template argument to the template
5897 parameter. This requires an exact match. */
5899 && !coerce_template_template_parms
5900 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5915 --processing_template_decl;
5919 /* Convert the indicated template ARG as necessary to match the
5920 indicated template PARM. Returns the converted ARG, or
5921 error_mark_node if the conversion was unsuccessful. Error and
5922 warning messages are issued under control of COMPLAIN. This
5923 conversion is for the Ith parameter in the parameter list. ARGS is
5924 the full set of template arguments deduced so far. */
5927 convert_template_argument (tree parm,
5930 tsubst_flags_t complain,
5936 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5938 if (TREE_CODE (arg) == TREE_LIST
5939 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5941 /* The template argument was the name of some
5942 member function. That's usually
5943 invalid, but static members are OK. In any
5944 case, grab the underlying fields/functions
5945 and issue an error later if required. */
5946 orig_arg = TREE_VALUE (arg);
5947 TREE_TYPE (arg) = unknown_type_node;
5952 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5953 requires_type = (TREE_CODE (parm) == TYPE_DECL
5954 || requires_tmpl_type);
5956 /* When determining whether an argument pack expansion is a template,
5957 look at the pattern. */
5958 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5959 arg = PACK_EXPANSION_PATTERN (arg);
5961 /* Deal with an injected-class-name used as a template template arg. */
5962 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5964 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5965 if (TREE_CODE (t) == TEMPLATE_DECL)
5967 if (cxx_dialect >= cxx0x)
5968 /* OK under DR 1004. */;
5969 else if (complain & tf_warning_or_error)
5970 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5971 " used as template template argument", TYPE_NAME (arg));
5972 else if (flag_pedantic_errors)
5980 ((TREE_CODE (arg) == TEMPLATE_DECL
5981 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5982 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5983 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5986 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5987 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5988 arg = TYPE_STUB_DECL (arg);
5990 is_type = TYPE_P (arg) || is_tmpl_type;
5992 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5993 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5995 permerror (input_location, "to refer to a type member of a template parameter, "
5996 "use %<typename %E%>", orig_arg);
5998 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5999 TREE_OPERAND (arg, 1),
6001 complain & tf_error);
6005 if (is_type != requires_type)
6009 if (complain & tf_error)
6011 error ("type/value mismatch at argument %d in template "
6012 "parameter list for %qD",
6015 error (" expected a constant of type %qT, got %qT",
6017 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6018 else if (requires_tmpl_type)
6019 error (" expected a class template, got %qE", orig_arg);
6021 error (" expected a type, got %qE", orig_arg);
6024 return error_mark_node;
6026 if (is_tmpl_type ^ requires_tmpl_type)
6028 if (in_decl && (complain & tf_error))
6030 error ("type/value mismatch at argument %d in template "
6031 "parameter list for %qD",
6034 error (" expected a type, got %qT", DECL_NAME (arg));
6036 error (" expected a class template, got %qT", orig_arg);
6038 return error_mark_node;
6043 if (requires_tmpl_type)
6045 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6046 /* The number of argument required is not known yet.
6047 Just accept it for now. */
6048 val = TREE_TYPE (arg);
6051 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6054 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6056 if (coerce_template_template_parms (parmparm, argparm,
6062 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6064 if (val != error_mark_node)
6066 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6067 val = TREE_TYPE (val);
6068 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6069 val = make_pack_expansion (val);
6074 if (in_decl && (complain & tf_error))
6076 error ("type/value mismatch at argument %d in "
6077 "template parameter list for %qD",
6079 error (" expected a template of type %qD, got %qT",
6083 val = error_mark_node;
6089 /* We only form one instance of each template specialization.
6090 Therefore, if we use a non-canonical variant (i.e., a
6091 typedef), any future messages referring to the type will use
6092 the typedef, which is confusing if those future uses do not
6093 themselves also use the typedef. */
6095 val = strip_typedefs (val);
6099 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6101 if (invalid_nontype_parm_type_p (t, complain))
6102 return error_mark_node;
6104 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6106 if (same_type_p (t, TREE_TYPE (orig_arg)))
6110 /* Not sure if this is reachable, but it doesn't hurt
6112 error ("type mismatch in nontype parameter pack");
6113 val = error_mark_node;
6116 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6117 /* We used to call digest_init here. However, digest_init
6118 will report errors, which we don't want when complain
6119 is zero. More importantly, digest_init will try too
6120 hard to convert things: for example, `0' should not be
6121 converted to pointer type at this point according to
6122 the standard. Accepting this is not merely an
6123 extension, since deciding whether or not these
6124 conversions can occur is part of determining which
6125 function template to call, or whether a given explicit
6126 argument specification is valid. */
6127 val = convert_nontype_argument (t, orig_arg, complain);
6131 if (val == NULL_TREE)
6132 val = error_mark_node;
6133 else if (val == error_mark_node && (complain & tf_error))
6134 error ("could not convert template argument %qE to %qT", orig_arg, t);
6136 if (TREE_CODE (val) == SCOPE_REF)
6138 /* Strip typedefs from the SCOPE_REF. */
6139 tree type = strip_typedefs (TREE_TYPE (val));
6140 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
6141 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6142 QUALIFIED_NAME_IS_TEMPLATE (val));
6149 /* Coerces the remaining template arguments in INNER_ARGS (from
6150 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6151 Returns the coerced argument pack. PARM_IDX is the position of this
6152 parameter in the template parameter list. ARGS is the original
6153 template argument list. */
6155 coerce_template_parameter_pack (tree parms,
6163 tsubst_flags_t complain)
6165 tree parm = TREE_VEC_ELT (parms, parm_idx);
6166 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6169 tree packed_types = NULL_TREE;
6171 if (arg_idx > nargs)
6174 packed_args = make_tree_vec (nargs - arg_idx);
6176 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6177 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6179 /* When the template parameter is a non-type template
6180 parameter pack whose type uses parameter packs, we need
6181 to look at each of the template arguments
6182 separately. Build a vector of the types for these
6183 non-type template parameters in PACKED_TYPES. */
6185 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6186 packed_types = tsubst_pack_expansion (expansion, args,
6189 if (packed_types == error_mark_node)
6190 return error_mark_node;
6192 /* Check that we have the right number of arguments. */
6194 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6195 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6198 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6199 error ("wrong number of template arguments (%d, should be %d)",
6200 nargs, needed_parms);
6201 return error_mark_node;
6204 /* If we aren't able to check the actual arguments now
6205 (because they haven't been expanded yet), we can at least
6206 verify that all of the types used for the non-type
6207 template parameter pack are, in fact, valid for non-type
6208 template parameters. */
6210 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6212 int j, len = TREE_VEC_LENGTH (packed_types);
6213 for (j = 0; j < len; ++j)
6215 tree t = TREE_VEC_ELT (packed_types, j);
6216 if (invalid_nontype_parm_type_p (t, complain))
6217 return error_mark_node;
6222 /* Convert the remaining arguments, which will be a part of the
6223 parameter pack "parm". */
6224 for (; arg_idx < nargs; ++arg_idx)
6226 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6227 tree actual_parm = TREE_VALUE (parm);
6229 if (packed_types && !PACK_EXPANSION_P (arg))
6231 /* When we have a vector of types (corresponding to the
6232 non-type template parameter pack that uses parameter
6233 packs in its type, as mention above), and the
6234 argument is not an expansion (which expands to a
6235 currently unknown number of arguments), clone the
6236 parm and give it the next type in PACKED_TYPES. */
6237 actual_parm = copy_node (actual_parm);
6238 TREE_TYPE (actual_parm) =
6239 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6242 if (arg != error_mark_node)
6243 arg = convert_template_argument (actual_parm,
6244 arg, new_args, complain, parm_idx,
6246 if (arg == error_mark_node)
6248 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6251 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6252 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6253 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6256 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6257 TREE_TYPE (argument_pack)
6258 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6259 TREE_CONSTANT (argument_pack) = 1;
6262 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6263 #ifdef ENABLE_CHECKING
6264 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6265 TREE_VEC_LENGTH (packed_args));
6267 return argument_pack;
6270 /* Convert all template arguments to their appropriate types, and
6271 return a vector containing the innermost resulting template
6272 arguments. If any error occurs, return error_mark_node. Error and
6273 warning messages are issued under control of COMPLAIN.
6275 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6276 for arguments not specified in ARGS. Otherwise, if
6277 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6278 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6279 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6283 coerce_template_parms (tree parms,
6286 tsubst_flags_t complain,
6287 bool require_all_args,
6288 bool use_default_args)
6290 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6293 tree new_inner_args;
6294 int saved_unevaluated_operand;
6295 int saved_inhibit_evaluation_warnings;
6297 /* When used as a boolean value, indicates whether this is a
6298 variadic template parameter list. Since it's an int, we can also
6299 subtract it from nparms to get the number of non-variadic
6303 if (args == error_mark_node)
6304 return error_mark_node;
6306 nparms = TREE_VEC_LENGTH (parms);
6308 /* Determine if there are any parameter packs. */
6309 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6311 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6312 if (template_parameter_pack_p (tparm))
6316 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6317 /* If there are 0 or 1 parameter packs, we need to expand any argument
6318 packs so that we can deduce a parameter pack from some non-packed args
6319 followed by an argument pack, as in variadic85.C. If there are more
6320 than that, we need to leave argument packs intact so the arguments are
6321 assigned to the right parameter packs. This should only happen when
6322 dealing with a nested class inside a partial specialization of a class
6323 template, as in variadic92.C. */
6324 if (variadic_p <= 1)
6325 inner_args = expand_template_argument_pack (inner_args);
6327 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6328 if ((nargs > nparms && !variadic_p)
6329 || (nargs < nparms - variadic_p
6331 && (!use_default_args
6332 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6333 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6335 if (complain & tf_error)
6340 error ("wrong number of template arguments "
6341 "(%d, should be %d or more)", nargs, nparms);
6344 error ("wrong number of template arguments "
6345 "(%d, should be %d)", nargs, nparms);
6348 error ("provided for %q+D", in_decl);
6351 return error_mark_node;
6354 /* We need to evaluate the template arguments, even though this
6355 template-id may be nested within a "sizeof". */
6356 saved_unevaluated_operand = cp_unevaluated_operand;
6357 cp_unevaluated_operand = 0;
6358 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6359 c_inhibit_evaluation_warnings = 0;
6360 new_inner_args = make_tree_vec (nparms);
6361 new_args = add_outermost_template_args (args, new_inner_args);
6362 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6367 /* Get the Ith template parameter. */
6368 parm = TREE_VEC_ELT (parms, parm_idx);
6370 if (parm == error_mark_node)
6372 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6376 /* Calculate the next argument. */
6377 if (arg_idx < nargs)
6378 arg = TREE_VEC_ELT (inner_args, arg_idx);
6382 if (template_parameter_pack_p (TREE_VALUE (parm))
6383 && !(arg && ARGUMENT_PACK_P (arg)))
6385 /* All remaining arguments will be placed in the
6386 template parameter pack PARM. */
6387 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6388 inner_args, arg_idx,
6392 /* Store this argument. */
6393 if (arg == error_mark_node)
6395 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6397 /* We are done with all of the arguments. */
6404 if (PACK_EXPANSION_P (arg))
6406 if (complain & tf_error)
6408 /* FIXME this restriction was removed by N2555; see
6410 /* If ARG is a pack expansion, but PARM is not a
6411 template parameter pack (if it were, we would have
6412 handled it above), we're trying to expand into a
6413 fixed-length argument list. */
6414 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6415 sorry ("cannot expand %<%E%> into a fixed-length "
6416 "argument list", arg);
6418 sorry ("cannot expand %<%T%> into a fixed-length "
6419 "argument list", arg);
6424 else if (require_all_args)
6426 /* There must be a default arg in this case. */
6427 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6429 /* The position of the first default template argument,
6430 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6432 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6433 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6438 if (arg == error_mark_node)
6440 if (complain & tf_error)
6441 error ("template argument %d is invalid", arg_idx + 1);
6444 /* This only occurs if there was an error in the template
6445 parameter list itself (which we would already have
6446 reported) that we are trying to recover from, e.g., a class
6447 template with a parameter list such as
6448 template<typename..., typename>. */
6451 arg = convert_template_argument (TREE_VALUE (parm),
6452 arg, new_args, complain,
6455 if (arg == error_mark_node)
6457 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6459 cp_unevaluated_operand = saved_unevaluated_operand;
6460 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6463 return error_mark_node;
6465 #ifdef ENABLE_CHECKING
6466 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6467 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6468 TREE_VEC_LENGTH (new_inner_args));
6471 return new_inner_args;
6474 /* Returns 1 if template args OT and NT are equivalent. */
6477 template_args_equal (tree ot, tree nt)
6481 if (nt == NULL_TREE || ot == NULL_TREE)
6484 if (TREE_CODE (nt) == TREE_VEC)
6485 /* For member templates */
6486 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6487 else if (PACK_EXPANSION_P (ot))
6488 return PACK_EXPANSION_P (nt)
6489 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6490 PACK_EXPANSION_PATTERN (nt));
6491 else if (ARGUMENT_PACK_P (ot))
6496 if (!ARGUMENT_PACK_P (nt))
6499 opack = ARGUMENT_PACK_ARGS (ot);
6500 npack = ARGUMENT_PACK_ARGS (nt);
6501 len = TREE_VEC_LENGTH (opack);
6502 if (TREE_VEC_LENGTH (npack) != len)
6504 for (i = 0; i < len; ++i)
6505 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6506 TREE_VEC_ELT (npack, i)))
6510 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6512 /* We get here probably because we are in the middle of substituting
6513 into the pattern of a pack expansion. In that case the
6514 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6515 interested in. So we want to use the initial pack argument for
6517 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6518 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6519 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6520 return template_args_equal (ot, nt);
6522 else if (TYPE_P (nt))
6523 return TYPE_P (ot) && same_type_p (ot, nt);
6524 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6527 return cp_tree_equal (ot, nt);
6530 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6531 of template arguments. Returns 0 otherwise. */
6534 comp_template_args (tree oldargs, tree newargs)
6538 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6541 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6543 tree nt = TREE_VEC_ELT (newargs, i);
6544 tree ot = TREE_VEC_ELT (oldargs, i);
6546 if (! template_args_equal (ot, nt))
6553 add_pending_template (tree d)
6555 tree ti = (TYPE_P (d)
6556 ? CLASSTYPE_TEMPLATE_INFO (d)
6557 : DECL_TEMPLATE_INFO (d));
6558 struct pending_template *pt;
6561 if (TI_PENDING_TEMPLATE_FLAG (ti))
6564 /* We are called both from instantiate_decl, where we've already had a
6565 tinst_level pushed, and instantiate_template, where we haven't.
6567 level = !current_tinst_level || current_tinst_level->decl != d;
6570 push_tinst_level (d);
6572 pt = ggc_alloc_pending_template ();
6574 pt->tinst = current_tinst_level;
6575 if (last_pending_template)
6576 last_pending_template->next = pt;
6578 pending_templates = pt;
6580 last_pending_template = pt;
6582 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6589 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6590 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6591 documentation for TEMPLATE_ID_EXPR. */
6594 lookup_template_function (tree fns, tree arglist)
6598 if (fns == error_mark_node || arglist == error_mark_node)
6599 return error_mark_node;
6601 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6602 gcc_assert (fns && (is_overloaded_fn (fns)
6603 || TREE_CODE (fns) == IDENTIFIER_NODE));
6605 if (BASELINK_P (fns))
6607 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6609 BASELINK_FUNCTIONS (fns),
6614 type = TREE_TYPE (fns);
6615 if (TREE_CODE (fns) == OVERLOAD || !type)
6616 type = unknown_type_node;
6618 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6621 /* Within the scope of a template class S<T>, the name S gets bound
6622 (in build_self_reference) to a TYPE_DECL for the class, not a
6623 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6624 or one of its enclosing classes, and that type is a template,
6625 return the associated TEMPLATE_DECL. Otherwise, the original
6628 Also handle the case when DECL is a TREE_LIST of ambiguous
6629 injected-class-names from different bases. */
6632 maybe_get_template_decl_from_type_decl (tree decl)
6634 if (decl == NULL_TREE)
6637 /* DR 176: A lookup that finds an injected-class-name (10.2
6638 [class.member.lookup]) can result in an ambiguity in certain cases
6639 (for example, if it is found in more than one base class). If all of
6640 the injected-class-names that are found refer to specializations of
6641 the same class template, and if the name is followed by a
6642 template-argument-list, the reference refers to the class template
6643 itself and not a specialization thereof, and is not ambiguous. */
6644 if (TREE_CODE (decl) == TREE_LIST)
6646 tree t, tmpl = NULL_TREE;
6647 for (t = decl; t; t = TREE_CHAIN (t))
6649 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6652 else if (tmpl != elt)
6655 if (tmpl && t == NULL_TREE)
6661 return (decl != NULL_TREE
6662 && DECL_SELF_REFERENCE_P (decl)
6663 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6664 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6667 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6668 parameters, find the desired type.
6670 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6672 IN_DECL, if non-NULL, is the template declaration we are trying to
6675 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6676 the class we are looking up.
6678 Issue error and warning messages under control of COMPLAIN.
6680 If the template class is really a local class in a template
6681 function, then the FUNCTION_CONTEXT is the function in which it is
6684 ??? Note that this function is currently called *twice* for each
6685 template-id: the first time from the parser, while creating the
6686 incomplete type (finish_template_type), and the second type during the
6687 real instantiation (instantiate_template_class). This is surely something
6688 that we want to avoid. It also causes some problems with argument
6689 coercion (see convert_nontype_argument for more information on this). */
6692 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
6693 int entering_scope, tsubst_flags_t complain)
6695 tree templ = NULL_TREE, parmlist;
6702 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6704 tree value = innermost_non_namespace_value (d1);
6705 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6710 push_decl_namespace (context);
6711 templ = lookup_name (d1);
6712 templ = maybe_get_template_decl_from_type_decl (templ);
6714 pop_decl_namespace ();
6717 context = DECL_CONTEXT (templ);
6719 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6721 tree type = TREE_TYPE (d1);
6723 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6724 an implicit typename for the second A. Deal with it. */
6725 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6726 type = TREE_TYPE (type);
6728 if (CLASSTYPE_TEMPLATE_INFO (type))
6730 templ = CLASSTYPE_TI_TEMPLATE (type);
6731 d1 = DECL_NAME (templ);
6734 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6735 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6737 templ = TYPE_TI_TEMPLATE (d1);
6738 d1 = DECL_NAME (templ);
6740 else if (TREE_CODE (d1) == TEMPLATE_DECL
6741 && DECL_TEMPLATE_RESULT (d1)
6742 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6745 d1 = DECL_NAME (templ);
6746 context = DECL_CONTEXT (templ);
6749 /* Issue an error message if we didn't find a template. */
6752 if (complain & tf_error)
6753 error ("%qT is not a template", d1);
6754 return error_mark_node;
6757 if (TREE_CODE (templ) != TEMPLATE_DECL
6758 /* Make sure it's a user visible template, if it was named by
6760 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6761 && !PRIMARY_TEMPLATE_P (templ)))
6763 if (complain & tf_error)
6765 error ("non-template type %qT used as a template", d1);
6767 error ("for template declaration %q+D", in_decl);
6769 return error_mark_node;
6772 complain &= ~tf_user;
6774 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6776 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6777 template arguments */
6783 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6785 /* Consider an example where a template template parameter declared as
6787 template <class T, class U = std::allocator<T> > class TT
6789 The template parameter level of T and U are one level larger than
6790 of TT. To proper process the default argument of U, say when an
6791 instantiation `TT<int>' is seen, we need to build the full
6792 arguments containing {int} as the innermost level. Outer levels,
6793 available when not appearing as default template argument, can be
6794 obtained from the arguments of the enclosing template.
6796 Suppose that TT is later substituted with std::vector. The above
6797 instantiation is `TT<int, std::allocator<T> >' with TT at
6798 level 1, and T at level 2, while the template arguments at level 1
6799 becomes {std::vector} and the inner level 2 is {int}. */
6801 outer = DECL_CONTEXT (templ);
6803 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6804 else if (current_template_parms)
6805 /* This is an argument of the current template, so we haven't set
6806 DECL_CONTEXT yet. */
6807 outer = current_template_args ();
6810 arglist = add_to_template_args (outer, arglist);
6812 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6814 /*require_all_args=*/true,
6815 /*use_default_args=*/true);
6816 if (arglist2 == error_mark_node
6817 || (!uses_template_parms (arglist2)
6818 && check_instantiated_args (templ, arglist2, complain)))
6819 return error_mark_node;
6821 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6826 tree template_type = TREE_TYPE (templ);
6829 tree found = NULL_TREE;
6832 int is_dependent_type;
6833 int use_partial_inst_tmpl = false;
6835 gen_tmpl = most_general_template (templ);
6836 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6837 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6838 arg_depth = TMPL_ARGS_DEPTH (arglist);
6840 if (arg_depth == 1 && parm_depth > 1)
6842 /* We've been given an incomplete set of template arguments.
6845 template <class T> struct S1 {
6846 template <class U> struct S2 {};
6847 template <class U> struct S2<U*> {};
6850 we will be called with an ARGLIST of `U*', but the
6851 TEMPLATE will be `template <class T> template
6852 <class U> struct S1<T>::S2'. We must fill in the missing
6855 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6857 arg_depth = TMPL_ARGS_DEPTH (arglist);
6860 /* Now we should have enough arguments. */
6861 gcc_assert (parm_depth == arg_depth);
6863 /* From here on, we're only interested in the most general
6866 /* Calculate the BOUND_ARGS. These will be the args that are
6867 actually tsubst'd into the definition to create the
6871 /* We have multiple levels of arguments to coerce, at once. */
6873 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6875 tree bound_args = make_tree_vec (parm_depth);
6877 for (i = saved_depth,
6878 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6879 i > 0 && t != NULL_TREE;
6880 --i, t = TREE_CHAIN (t))
6883 if (i == saved_depth)
6884 a = coerce_template_parms (TREE_VALUE (t),
6887 /*require_all_args=*/true,
6888 /*use_default_args=*/true);
6890 /* Outer levels should have already been coerced. */
6891 a = TMPL_ARGS_LEVEL (arglist, i);
6893 /* Don't process further if one of the levels fails. */
6894 if (a == error_mark_node)
6896 /* Restore the ARGLIST to its full size. */
6897 TREE_VEC_LENGTH (arglist) = saved_depth;
6898 return error_mark_node;
6901 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6903 /* We temporarily reduce the length of the ARGLIST so
6904 that coerce_template_parms will see only the arguments
6905 corresponding to the template parameters it is
6907 TREE_VEC_LENGTH (arglist)--;
6910 /* Restore the ARGLIST to its full size. */
6911 TREE_VEC_LENGTH (arglist) = saved_depth;
6913 arglist = bound_args;
6917 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6918 INNERMOST_TEMPLATE_ARGS (arglist),
6921 /*require_all_args=*/true,
6922 /*use_default_args=*/true);
6924 if (arglist == error_mark_node)
6925 /* We were unable to bind the arguments. */
6926 return error_mark_node;
6928 /* In the scope of a template class, explicit references to the
6929 template class refer to the type of the template, not any
6930 instantiation of it. For example, in:
6932 template <class T> class C { void f(C<T>); }
6934 the `C<T>' is just the same as `C'. Outside of the
6935 class, however, such a reference is an instantiation. */
6937 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6938 || currently_open_class (template_type))
6939 /* comp_template_args is expensive, check it last. */
6940 && comp_template_args (TYPE_TI_ARGS (template_type),
6942 return template_type;
6944 /* If we already have this specialization, return it. */
6945 elt.tmpl = gen_tmpl;
6947 hash = hash_specialization (&elt);
6948 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6954 is_dependent_type = uses_template_parms (arglist);
6956 /* If the deduced arguments are invalid, then the binding
6958 if (!is_dependent_type
6959 && check_instantiated_args (gen_tmpl,
6960 INNERMOST_TEMPLATE_ARGS (arglist),
6962 return error_mark_node;
6964 if (!is_dependent_type
6965 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6966 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6967 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6969 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6970 DECL_NAME (gen_tmpl),
6971 /*tag_scope=*/ts_global);
6975 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6978 context = global_namespace;
6980 /* Create the type. */
6981 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6983 if (!is_dependent_type)
6985 set_current_access_from_decl (TYPE_NAME (template_type));
6986 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
6987 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6988 arglist, complain, in_decl),
6989 SCOPED_ENUM_P (template_type), NULL);
6993 /* We don't want to call start_enum for this type, since
6994 the values for the enumeration constants may involve
6995 template parameters. And, no one should be interested
6996 in the enumeration constants for such a type. */
6997 t = cxx_make_type (ENUMERAL_TYPE);
6998 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7000 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7001 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7002 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7006 t = make_class_type (TREE_CODE (template_type));
7007 CLASSTYPE_DECLARED_CLASS (t)
7008 = CLASSTYPE_DECLARED_CLASS (template_type);
7009 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7010 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7012 /* A local class. Make sure the decl gets registered properly. */
7013 if (context == current_function_decl)
7014 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7016 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7017 /* This instantiation is another name for the primary
7018 template type. Set the TYPE_CANONICAL field
7020 TYPE_CANONICAL (t) = template_type;
7021 else if (any_template_arguments_need_structural_equality_p (arglist))
7022 /* Some of the template arguments require structural
7023 equality testing, so this template class requires
7024 structural equality testing. */
7025 SET_TYPE_STRUCTURAL_EQUALITY (t);
7028 /* If we called start_enum or pushtag above, this information
7029 will already be set up. */
7032 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7034 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7035 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7036 DECL_SOURCE_LOCATION (type_decl)
7037 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7040 type_decl = TYPE_NAME (t);
7042 TREE_PRIVATE (type_decl)
7043 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7044 TREE_PROTECTED (type_decl)
7045 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7046 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7048 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7049 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7052 /* Let's consider the explicit specialization of a member
7053 of a class template specialization that is implicitely instantiated,
7058 template<class U> struct M {}; //#0
7063 struct S<int>::M<char> //#1
7067 [temp.expl.spec]/4 says this is valid.
7069 In this case, when we write:
7072 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7075 When we encounter #1, we want to store the partial instantiation
7076 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7078 For all cases other than this "explicit specialization of member of a
7079 class template", we just want to store the most general template into
7080 the CLASSTYPE_TI_TEMPLATE of M.
7082 This case of "explicit specialization of member of a class template"
7084 1/ the enclosing class is an instantiation of, and therefore not
7085 the same as, the context of the most general template, and
7086 2/ we aren't looking at the partial instantiation itself, i.e.
7087 the innermost arguments are not the same as the innermost parms of
7088 the most general template.
7090 So it's only when 1/ and 2/ happens that we want to use the partial
7091 instantiation of the member template in lieu of its most general
7094 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7095 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7096 /* the enclosing class must be an instantiation... */
7097 && CLASS_TYPE_P (context)
7098 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7100 tree partial_inst_args;
7101 TREE_VEC_LENGTH (arglist)--;
7102 ++processing_template_decl;
7104 tsubst (INNERMOST_TEMPLATE_ARGS
7105 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7106 arglist, complain, NULL_TREE);
7107 --processing_template_decl;
7108 TREE_VEC_LENGTH (arglist)++;
7109 use_partial_inst_tmpl =
7110 /*...and we must not be looking at the partial instantiation
7112 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7116 if (!use_partial_inst_tmpl)
7117 /* This case is easy; there are no member templates involved. */
7121 /* This is a full instantiation of a member template. Find
7122 the partial instantiation of which this is an instance. */
7124 /* Temporarily reduce by one the number of levels in the ARGLIST
7125 so as to avoid comparing the last set of arguments. */
7126 TREE_VEC_LENGTH (arglist)--;
7127 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7128 TREE_VEC_LENGTH (arglist)++;
7129 found = CLASSTYPE_TI_TEMPLATE (found);
7132 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7135 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
7136 &elt, hash, INSERT);
7137 *slot = ggc_alloc_spec_entry ();
7140 /* Note this use of the partial instantiation so we can check it
7141 later in maybe_process_partial_specialization. */
7142 DECL_TEMPLATE_INSTANTIATIONS (templ)
7143 = tree_cons (arglist, t,
7144 DECL_TEMPLATE_INSTANTIATIONS (templ));
7146 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7147 /* Now that the type has been registered on the instantiations
7148 list, we set up the enumerators. Because the enumeration
7149 constants may involve the enumeration type itself, we make
7150 sure to register the type first, and then create the
7151 constants. That way, doing tsubst_expr for the enumeration
7152 constants won't result in recursive calls here; we'll find
7153 the instantiation and exit above. */
7154 tsubst_enum (template_type, t, arglist);
7156 if (is_dependent_type)
7157 /* If the type makes use of template parameters, the
7158 code that generates debugging information will crash. */
7159 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7161 /* Possibly limit visibility based on template args. */
7162 TREE_PUBLIC (type_decl) = 1;
7163 determine_visibility (type_decl);
7169 /* Wrapper for lookup_template_class_1. */
7172 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7173 int entering_scope, tsubst_flags_t complain)
7176 timevar_push (TV_TEMPLATE_INST);
7177 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7178 entering_scope, complain);
7179 timevar_pop (TV_TEMPLATE_INST);
7187 /* True when we should also visit template parameters that occur in
7188 non-deduced contexts. */
7189 bool include_nondeduced_p;
7190 struct pointer_set_t *visited;
7193 /* Called from for_each_template_parm via walk_tree. */
7196 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7199 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7200 tree_fn_t fn = pfd->fn;
7201 void *data = pfd->data;
7204 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7205 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7206 pfd->include_nondeduced_p))
7207 return error_mark_node;
7209 switch (TREE_CODE (t))
7212 if (TYPE_PTRMEMFUNC_P (t))
7218 if (!TYPE_TEMPLATE_INFO (t))
7220 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7221 fn, data, pfd->visited,
7222 pfd->include_nondeduced_p))
7223 return error_mark_node;
7227 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7228 fn, data, pfd->visited,
7229 pfd->include_nondeduced_p)
7230 || for_each_template_parm (TYPE_MAX_VALUE (t),
7231 fn, data, pfd->visited,
7232 pfd->include_nondeduced_p))
7233 return error_mark_node;
7237 /* Since we're not going to walk subtrees, we have to do this
7239 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7240 pfd->visited, pfd->include_nondeduced_p))
7241 return error_mark_node;
7245 /* Check the return type. */
7246 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7247 pfd->include_nondeduced_p))
7248 return error_mark_node;
7250 /* Check the parameter types. Since default arguments are not
7251 instantiated until they are needed, the TYPE_ARG_TYPES may
7252 contain expressions that involve template parameters. But,
7253 no-one should be looking at them yet. And, once they're
7254 instantiated, they don't contain template parameters, so
7255 there's no point in looking at them then, either. */
7259 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7260 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7261 pfd->visited, pfd->include_nondeduced_p))
7262 return error_mark_node;
7264 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7265 want walk_tree walking into them itself. */
7271 case UNDERLYING_TYPE:
7272 if (pfd->include_nondeduced_p
7273 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7275 pfd->include_nondeduced_p))
7276 return error_mark_node;
7281 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7282 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7283 pfd->visited, pfd->include_nondeduced_p))
7284 return error_mark_node;
7289 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7290 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7291 pfd->visited, pfd->include_nondeduced_p))
7292 return error_mark_node;
7293 if (DECL_CONTEXT (t)
7294 && pfd->include_nondeduced_p
7295 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7296 pfd->visited, pfd->include_nondeduced_p))
7297 return error_mark_node;
7300 case BOUND_TEMPLATE_TEMPLATE_PARM:
7301 /* Record template parameters such as `T' inside `TT<T>'. */
7302 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7303 pfd->include_nondeduced_p))
7304 return error_mark_node;
7307 case TEMPLATE_TEMPLATE_PARM:
7308 case TEMPLATE_TYPE_PARM:
7309 case TEMPLATE_PARM_INDEX:
7310 if (fn && (*fn)(t, data))
7311 return error_mark_node;
7313 return error_mark_node;
7317 /* A template template parameter is encountered. */
7318 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7319 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7320 pfd->include_nondeduced_p))
7321 return error_mark_node;
7323 /* Already substituted template template parameter */
7329 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7331 pfd->include_nondeduced_p))
7332 return error_mark_node;
7336 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7337 && pfd->include_nondeduced_p
7338 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7339 (TREE_TYPE (t)), fn, data,
7340 pfd->visited, pfd->include_nondeduced_p))
7341 return error_mark_node;
7346 /* If there's no type, then this thing must be some expression
7347 involving template parameters. */
7348 if (!fn && !TREE_TYPE (t))
7349 return error_mark_node;
7354 case REINTERPRET_CAST_EXPR:
7355 case CONST_CAST_EXPR:
7356 case STATIC_CAST_EXPR:
7357 case DYNAMIC_CAST_EXPR:
7361 case PSEUDO_DTOR_EXPR:
7363 return error_mark_node;
7370 /* We didn't find any template parameters we liked. */
7374 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7375 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7376 call FN with the parameter and the DATA.
7377 If FN returns nonzero, the iteration is terminated, and
7378 for_each_template_parm returns 1. Otherwise, the iteration
7379 continues. If FN never returns a nonzero value, the value
7380 returned by for_each_template_parm is 0. If FN is NULL, it is
7381 considered to be the function which always returns 1.
7383 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7384 parameters that occur in non-deduced contexts. When false, only
7385 visits those template parameters that can be deduced. */
7388 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7389 struct pointer_set_t *visited,
7390 bool include_nondeduced_p)
7392 struct pair_fn_data pfd;
7398 pfd.include_nondeduced_p = include_nondeduced_p;
7400 /* Walk the tree. (Conceptually, we would like to walk without
7401 duplicates, but for_each_template_parm_r recursively calls
7402 for_each_template_parm, so we would need to reorganize a fair
7403 bit to use walk_tree_without_duplicates, so we keep our own
7406 pfd.visited = visited;
7408 pfd.visited = pointer_set_create ();
7409 result = cp_walk_tree (&t,
7410 for_each_template_parm_r,
7412 pfd.visited) != NULL_TREE;
7417 pointer_set_destroy (pfd.visited);
7424 /* Returns true if T depends on any template parameter. */
7427 uses_template_parms (tree t)
7430 int saved_processing_template_decl;
7432 saved_processing_template_decl = processing_template_decl;
7433 if (!saved_processing_template_decl)
7434 processing_template_decl = 1;
7436 dependent_p = dependent_type_p (t);
7437 else if (TREE_CODE (t) == TREE_VEC)
7438 dependent_p = any_dependent_template_arguments_p (t);
7439 else if (TREE_CODE (t) == TREE_LIST)
7440 dependent_p = (uses_template_parms (TREE_VALUE (t))
7441 || uses_template_parms (TREE_CHAIN (t)));
7442 else if (TREE_CODE (t) == TYPE_DECL)
7443 dependent_p = dependent_type_p (TREE_TYPE (t));
7446 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7447 || TREE_CODE (t) == OVERLOAD
7448 || TREE_CODE (t) == BASELINK
7449 || TREE_CODE (t) == IDENTIFIER_NODE
7450 || TREE_CODE (t) == TRAIT_EXPR
7451 || TREE_CODE (t) == CONSTRUCTOR
7452 || CONSTANT_CLASS_P (t))
7453 dependent_p = (type_dependent_expression_p (t)
7454 || value_dependent_expression_p (t));
7457 gcc_assert (t == error_mark_node);
7458 dependent_p = false;
7461 processing_template_decl = saved_processing_template_decl;
7466 /* Returns true if T depends on any template parameter with level LEVEL. */
7469 uses_template_parms_level (tree t, int level)
7471 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7472 /*include_nondeduced_p=*/true);
7475 static int tinst_depth;
7476 extern int max_tinst_depth;
7477 #ifdef GATHER_STATISTICS
7480 static int tinst_level_tick;
7481 static int last_template_error_tick;
7483 /* We're starting to instantiate D; record the template instantiation context
7484 for diagnostics and to restore it later. */
7487 push_tinst_level (tree d)
7489 struct tinst_level *new_level;
7491 if (tinst_depth >= max_tinst_depth)
7493 last_template_error_tick = tinst_level_tick;
7494 if (TREE_CODE (d) == TREE_LIST)
7495 error ("template instantiation depth exceeds maximum of %d (use "
7496 "-ftemplate-depth= to increase the maximum) substituting %qS",
7497 max_tinst_depth, d);
7499 error ("template instantiation depth exceeds maximum of %d (use "
7500 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7501 max_tinst_depth, d);
7503 print_instantiation_context ();
7508 new_level = ggc_alloc_tinst_level ();
7509 new_level->decl = d;
7510 new_level->locus = input_location;
7511 new_level->in_system_header_p = in_system_header;
7512 new_level->next = current_tinst_level;
7513 current_tinst_level = new_level;
7516 #ifdef GATHER_STATISTICS
7517 if (tinst_depth > depth_reached)
7518 depth_reached = tinst_depth;
7525 /* We're done instantiating this template; return to the instantiation
7529 pop_tinst_level (void)
7531 /* Restore the filename and line number stashed away when we started
7532 this instantiation. */
7533 input_location = current_tinst_level->locus;
7534 current_tinst_level = current_tinst_level->next;
7539 /* We're instantiating a deferred template; restore the template
7540 instantiation context in which the instantiation was requested, which
7541 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7544 reopen_tinst_level (struct tinst_level *level)
7546 struct tinst_level *t;
7549 for (t = level; t; t = t->next)
7552 current_tinst_level = level;
7557 /* Returns the TINST_LEVEL which gives the original instantiation
7560 struct tinst_level *
7561 outermost_tinst_level (void)
7563 struct tinst_level *level = current_tinst_level;
7566 level = level->next;
7570 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7573 parameter_of_template_p (tree parm, tree templ)
7578 if (!parm || !templ)
7581 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7582 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7584 parms = DECL_TEMPLATE_PARMS (templ);
7585 parms = INNERMOST_TEMPLATE_PARMS (parms);
7587 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7588 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7594 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7595 vector of template arguments, as for tsubst.
7597 Returns an appropriate tsubst'd friend declaration. */
7600 tsubst_friend_function (tree decl, tree args)
7604 if (TREE_CODE (decl) == FUNCTION_DECL
7605 && DECL_TEMPLATE_INSTANTIATION (decl)
7606 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7607 /* This was a friend declared with an explicit template
7608 argument list, e.g.:
7612 to indicate that f was a template instantiation, not a new
7613 function declaration. Now, we have to figure out what
7614 instantiation of what template. */
7616 tree template_id, arglist, fns;
7619 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7621 /* Friend functions are looked up in the containing namespace scope.
7622 We must enter that scope, to avoid finding member functions of the
7623 current class with same name. */
7624 push_nested_namespace (ns);
7625 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7626 tf_warning_or_error, NULL_TREE,
7627 /*integral_constant_expression_p=*/false);
7628 pop_nested_namespace (ns);
7629 arglist = tsubst (DECL_TI_ARGS (decl), args,
7630 tf_warning_or_error, NULL_TREE);
7631 template_id = lookup_template_function (fns, arglist);
7633 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7634 tmpl = determine_specialization (template_id, new_friend,
7636 /*need_member_template=*/0,
7637 TREE_VEC_LENGTH (args),
7639 return instantiate_template (tmpl, new_args, tf_error);
7642 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7644 /* The NEW_FRIEND will look like an instantiation, to the
7645 compiler, but is not an instantiation from the point of view of
7646 the language. For example, we might have had:
7648 template <class T> struct S {
7649 template <class U> friend void f(T, U);
7652 Then, in S<int>, template <class U> void f(int, U) is not an
7653 instantiation of anything. */
7654 if (new_friend == error_mark_node)
7655 return error_mark_node;
7657 DECL_USE_TEMPLATE (new_friend) = 0;
7658 if (TREE_CODE (decl) == TEMPLATE_DECL)
7660 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7661 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7662 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7665 /* The mangled name for the NEW_FRIEND is incorrect. The function
7666 is not a template instantiation and should not be mangled like
7667 one. Therefore, we forget the mangling here; we'll recompute it
7668 later if we need it. */
7669 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7671 SET_DECL_RTL (new_friend, NULL);
7672 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7675 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7678 tree new_friend_template_info;
7679 tree new_friend_result_template_info;
7681 int new_friend_is_defn;
7683 /* We must save some information from NEW_FRIEND before calling
7684 duplicate decls since that function will free NEW_FRIEND if
7686 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7687 new_friend_is_defn =
7688 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7689 (template_for_substitution (new_friend)))
7691 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7693 /* This declaration is a `primary' template. */
7694 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7696 new_friend_result_template_info
7697 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7700 new_friend_result_template_info = NULL_TREE;
7702 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7703 if (new_friend_is_defn)
7704 DECL_INITIAL (new_friend) = error_mark_node;
7706 /* Inside pushdecl_namespace_level, we will push into the
7707 current namespace. However, the friend function should go
7708 into the namespace of the template. */
7709 ns = decl_namespace_context (new_friend);
7710 push_nested_namespace (ns);
7711 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7712 pop_nested_namespace (ns);
7714 if (old_decl == error_mark_node)
7715 return error_mark_node;
7717 if (old_decl != new_friend)
7719 /* This new friend declaration matched an existing
7720 declaration. For example, given:
7722 template <class T> void f(T);
7723 template <class U> class C {
7724 template <class T> friend void f(T) {}
7727 the friend declaration actually provides the definition
7728 of `f', once C has been instantiated for some type. So,
7729 old_decl will be the out-of-class template declaration,
7730 while new_friend is the in-class definition.
7732 But, if `f' was called before this point, the
7733 instantiation of `f' will have DECL_TI_ARGS corresponding
7734 to `T' but not to `U', references to which might appear
7735 in the definition of `f'. Previously, the most general
7736 template for an instantiation of `f' was the out-of-class
7737 version; now it is the in-class version. Therefore, we
7738 run through all specialization of `f', adding to their
7739 DECL_TI_ARGS appropriately. In particular, they need a
7740 new set of outer arguments, corresponding to the
7741 arguments for this class instantiation.
7743 The same situation can arise with something like this:
7746 template <class T> class C {
7750 when `C<int>' is instantiated. Now, `f(int)' is defined
7753 if (!new_friend_is_defn)
7754 /* On the other hand, if the in-class declaration does
7755 *not* provide a definition, then we don't want to alter
7756 existing definitions. We can just leave everything
7761 tree new_template = TI_TEMPLATE (new_friend_template_info);
7762 tree new_args = TI_ARGS (new_friend_template_info);
7764 /* Overwrite whatever template info was there before, if
7765 any, with the new template information pertaining to
7767 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7769 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7771 /* We should have called reregister_specialization in
7773 gcc_assert (retrieve_specialization (new_template,
7777 /* Instantiate it if the global has already been used. */
7778 if (DECL_ODR_USED (old_decl))
7779 instantiate_decl (old_decl, /*defer_ok=*/true,
7780 /*expl_inst_class_mem_p=*/false);
7786 /* Indicate that the old function template is a partial
7788 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7789 = new_friend_result_template_info;
7791 gcc_assert (new_template
7792 == most_general_template (new_template));
7793 gcc_assert (new_template != old_decl);
7795 /* Reassign any specializations already in the hash table
7796 to the new more general template, and add the
7797 additional template args. */
7798 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7802 tree spec = TREE_VALUE (t);
7805 elt.tmpl = old_decl;
7806 elt.args = DECL_TI_ARGS (spec);
7807 elt.spec = NULL_TREE;
7809 htab_remove_elt (decl_specializations, &elt);
7812 = add_outermost_template_args (new_args,
7813 DECL_TI_ARGS (spec));
7815 register_specialization
7816 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7819 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7823 /* The information from NEW_FRIEND has been merged into OLD_DECL
7824 by duplicate_decls. */
7825 new_friend = old_decl;
7830 tree context = DECL_CONTEXT (new_friend);
7834 template <class T> class C {
7835 template <class U> friend void C1<U>::f (); // case 1
7836 friend void C2<T>::f (); // case 2
7838 we only need to make sure CONTEXT is a complete type for
7839 case 2. To distinguish between the two cases, we note that
7840 CONTEXT of case 1 remains dependent type after tsubst while
7841 this isn't true for case 2. */
7842 ++processing_template_decl;
7843 dependent_p = dependent_type_p (context);
7844 --processing_template_decl;
7847 && !complete_type_or_else (context, NULL_TREE))
7848 return error_mark_node;
7850 if (COMPLETE_TYPE_P (context))
7852 /* Check to see that the declaration is really present, and,
7853 possibly obtain an improved declaration. */
7854 tree fn = check_classfn (context,
7855 new_friend, NULL_TREE);
7865 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7866 template arguments, as for tsubst.
7868 Returns an appropriate tsubst'd friend type or error_mark_node on
7872 tsubst_friend_class (tree friend_tmpl, tree args)
7878 context = CP_DECL_CONTEXT (friend_tmpl);
7880 if (context != global_namespace)
7882 if (TREE_CODE (context) == NAMESPACE_DECL)
7883 push_nested_namespace (context);
7885 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7888 /* Look for a class template declaration. We look for hidden names
7889 because two friend declarations of the same template are the
7890 same. For example, in:
7893 template <typename> friend class F;
7895 template <typename> struct B {
7896 template <typename> friend class F;
7899 both F templates are the same. */
7900 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7901 /*block_p=*/true, 0,
7902 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7904 /* But, if we don't find one, it might be because we're in a
7905 situation like this:
7913 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7914 for `S<int>', not the TEMPLATE_DECL. */
7915 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7917 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7918 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7921 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7923 /* The friend template has already been declared. Just
7924 check to see that the declarations match, and install any new
7925 default parameters. We must tsubst the default parameters,
7926 of course. We only need the innermost template parameters
7927 because that is all that redeclare_class_template will look
7929 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7930 > TMPL_ARGS_DEPTH (args))
7933 location_t saved_input_location;
7934 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7935 args, tf_warning_or_error);
7937 saved_input_location = input_location;
7938 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7939 redeclare_class_template (TREE_TYPE (tmpl), parms);
7940 input_location = saved_input_location;
7944 friend_type = TREE_TYPE (tmpl);
7948 /* The friend template has not already been declared. In this
7949 case, the instantiation of the template class will cause the
7950 injection of this template into the global scope. */
7951 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7952 if (tmpl == error_mark_node)
7953 return error_mark_node;
7955 /* The new TMPL is not an instantiation of anything, so we
7956 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7957 the new type because that is supposed to be the corresponding
7958 template decl, i.e., TMPL. */
7959 DECL_USE_TEMPLATE (tmpl) = 0;
7960 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7961 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7962 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7963 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7965 /* Inject this template into the global scope. */
7966 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7969 if (context != global_namespace)
7971 if (TREE_CODE (context) == NAMESPACE_DECL)
7972 pop_nested_namespace (context);
7974 pop_nested_class ();
7980 /* Returns zero if TYPE cannot be completed later due to circularity.
7981 Otherwise returns one. */
7984 can_complete_type_without_circularity (tree type)
7986 if (type == NULL_TREE || type == error_mark_node)
7988 else if (COMPLETE_TYPE_P (type))
7990 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7991 return can_complete_type_without_circularity (TREE_TYPE (type));
7992 else if (CLASS_TYPE_P (type)
7993 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7999 /* Apply any attributes which had to be deferred until instantiation
8000 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8001 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8004 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8005 tree args, tsubst_flags_t complain, tree in_decl)
8007 tree last_dep = NULL_TREE;
8011 for (t = attributes; t; t = TREE_CHAIN (t))
8012 if (ATTR_IS_DEPENDENT (t))
8015 attributes = copy_list (attributes);
8019 if (DECL_P (*decl_p))
8021 if (TREE_TYPE (*decl_p) == error_mark_node)
8023 p = &DECL_ATTRIBUTES (*decl_p);
8026 p = &TYPE_ATTRIBUTES (*decl_p);
8030 tree late_attrs = NULL_TREE;
8031 tree *q = &late_attrs;
8033 for (*p = attributes; *p; )
8036 if (ATTR_IS_DEPENDENT (t))
8038 *p = TREE_CHAIN (t);
8039 TREE_CHAIN (t) = NULL_TREE;
8040 /* If the first attribute argument is an identifier, don't
8041 pass it through tsubst. Attributes like mode, format,
8042 cleanup and several target specific attributes expect it
8045 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8046 && TREE_VALUE (TREE_VALUE (t))
8047 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8048 == IDENTIFIER_NODE))
8051 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8053 /*integral_constant_expression_p=*/false);
8054 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8056 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8061 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8062 /*integral_constant_expression_p=*/false);
8064 q = &TREE_CHAIN (t);
8067 p = &TREE_CHAIN (t);
8070 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8074 /* Perform (or defer) access check for typedefs that were referenced
8075 from within the template TMPL code.
8076 This is a subroutine of instantiate_template and instantiate_class_template.
8077 TMPL is the template to consider and TARGS is the list of arguments of
8081 perform_typedefs_access_check (tree tmpl, tree targs)
8083 location_t saved_location;
8085 qualified_typedef_usage_t *iter;
8088 || (!CLASS_TYPE_P (tmpl)
8089 && TREE_CODE (tmpl) != FUNCTION_DECL))
8092 saved_location = input_location;
8093 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8094 get_types_needing_access_check (tmpl),
8097 tree type_decl = iter->typedef_decl;
8098 tree type_scope = iter->context;
8100 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8103 if (uses_template_parms (type_decl))
8104 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8105 if (uses_template_parms (type_scope))
8106 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8108 /* Make access check error messages point to the location
8109 of the use of the typedef. */
8110 input_location = iter->locus;
8111 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8112 type_decl, type_decl);
8114 input_location = saved_location;
8118 instantiate_class_template_1 (tree type)
8120 tree templ, args, pattern, t, member;
8124 unsigned int saved_maximum_field_alignment;
8126 if (type == error_mark_node)
8127 return error_mark_node;
8129 if (COMPLETE_OR_OPEN_TYPE_P (type)
8130 || uses_template_parms (type))
8133 /* Figure out which template is being instantiated. */
8134 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8135 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8137 /* Determine what specialization of the original template to
8139 t = most_specialized_class (type, templ, tf_warning_or_error);
8140 if (t == error_mark_node)
8142 TYPE_BEING_DEFINED (type) = 1;
8143 return error_mark_node;
8147 /* This TYPE is actually an instantiation of a partial
8148 specialization. We replace the innermost set of ARGS with
8149 the arguments appropriate for substitution. For example,
8152 template <class T> struct S {};
8153 template <class T> struct S<T*> {};
8155 and supposing that we are instantiating S<int*>, ARGS will
8156 presently be {int*} -- but we need {int}. */
8157 pattern = TREE_TYPE (t);
8158 args = TREE_PURPOSE (t);
8162 pattern = TREE_TYPE (templ);
8163 args = CLASSTYPE_TI_ARGS (type);
8166 /* If the template we're instantiating is incomplete, then clearly
8167 there's nothing we can do. */
8168 if (!COMPLETE_TYPE_P (pattern))
8171 /* If we've recursively instantiated too many templates, stop. */
8172 if (! push_tinst_level (type))
8175 /* Now we're really doing the instantiation. Mark the type as in
8176 the process of being defined. */
8177 TYPE_BEING_DEFINED (type) = 1;
8179 /* We may be in the middle of deferred access check. Disable
8181 push_deferring_access_checks (dk_no_deferred);
8183 push_to_top_level ();
8184 /* Use #pragma pack from the template context. */
8185 saved_maximum_field_alignment = maximum_field_alignment;
8186 maximum_field_alignment = TYPE_PRECISION (pattern);
8188 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8190 /* Set the input location to the most specialized template definition.
8191 This is needed if tsubsting causes an error. */
8192 typedecl = TYPE_MAIN_DECL (pattern);
8193 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8194 DECL_SOURCE_LOCATION (typedecl);
8196 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
8197 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
8198 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
8199 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
8200 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
8201 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
8202 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
8203 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
8204 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
8205 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
8206 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8207 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8208 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8209 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8210 if (ANON_AGGR_TYPE_P (pattern))
8211 SET_ANON_AGGR_TYPE_P (type);
8212 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8214 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8215 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8217 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8219 pbinfo = TYPE_BINFO (pattern);
8221 /* We should never instantiate a nested class before its enclosing
8222 class; we need to look up the nested class by name before we can
8223 instantiate it, and that lookup should instantiate the enclosing
8225 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8226 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8228 base_list = NULL_TREE;
8229 if (BINFO_N_BASE_BINFOS (pbinfo))
8235 /* We must enter the scope containing the type, as that is where
8236 the accessibility of types named in dependent bases are
8238 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8240 /* Substitute into each of the bases to determine the actual
8242 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8245 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8246 tree expanded_bases = NULL_TREE;
8249 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8252 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8253 args, tf_error, NULL_TREE);
8254 if (expanded_bases == error_mark_node)
8257 len = TREE_VEC_LENGTH (expanded_bases);
8260 for (idx = 0; idx < len; idx++)
8263 /* Extract the already-expanded base class. */
8264 base = TREE_VEC_ELT (expanded_bases, idx);
8266 /* Substitute to figure out the base class. */
8267 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8270 if (base == error_mark_node)
8273 base_list = tree_cons (access, base, base_list);
8274 if (BINFO_VIRTUAL_P (pbase_binfo))
8275 TREE_TYPE (base_list) = integer_type_node;
8279 /* The list is now in reverse order; correct that. */
8280 base_list = nreverse (base_list);
8283 pop_scope (pushed_scope);
8285 /* Now call xref_basetypes to set up all the base-class
8287 xref_basetypes (type, base_list);
8289 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8290 (int) ATTR_FLAG_TYPE_IN_PLACE,
8291 args, tf_error, NULL_TREE);
8292 fixup_attribute_variants (type);
8294 /* Now that our base classes are set up, enter the scope of the
8295 class, so that name lookups into base classes, etc. will work
8296 correctly. This is precisely analogous to what we do in
8297 begin_class_definition when defining an ordinary non-template
8298 class, except we also need to push the enclosing classes. */
8299 push_nested_class (type);
8301 /* Now members are processed in the order of declaration. */
8302 for (member = CLASSTYPE_DECL_LIST (pattern);
8303 member; member = TREE_CHAIN (member))
8305 tree t = TREE_VALUE (member);
8307 if (TREE_PURPOSE (member))
8311 /* Build new CLASSTYPE_NESTED_UTDS. */
8314 bool class_template_p;
8316 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8317 && TYPE_LANG_SPECIFIC (t)
8318 && CLASSTYPE_IS_TEMPLATE (t));
8319 /* If the member is a class template, then -- even after
8320 substitution -- there may be dependent types in the
8321 template argument list for the class. We increment
8322 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8323 that function will assume that no types are dependent
8324 when outside of a template. */
8325 if (class_template_p)
8326 ++processing_template_decl;
8327 newtag = tsubst (t, args, tf_error, NULL_TREE);
8328 if (class_template_p)
8329 --processing_template_decl;
8330 if (newtag == error_mark_node)
8333 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8335 tree name = TYPE_IDENTIFIER (t);
8337 if (class_template_p)
8338 /* Unfortunately, lookup_template_class sets
8339 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8340 instantiation (i.e., for the type of a member
8341 template class nested within a template class.)
8342 This behavior is required for
8343 maybe_process_partial_specialization to work
8344 correctly, but is not accurate in this case;
8345 the TAG is not an instantiation of anything.
8346 (The corresponding TEMPLATE_DECL is an
8347 instantiation, but the TYPE is not.) */
8348 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8350 /* Now, we call pushtag to put this NEWTAG into the scope of
8351 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8352 pushtag calling push_template_decl. We don't have to do
8353 this for enums because it will already have been done in
8356 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8357 pushtag (name, newtag, /*tag_scope=*/ts_current);
8360 else if (TREE_CODE (t) == FUNCTION_DECL
8361 || DECL_FUNCTION_TEMPLATE_P (t))
8363 /* Build new TYPE_METHODS. */
8366 if (TREE_CODE (t) == TEMPLATE_DECL)
8367 ++processing_template_decl;
8368 r = tsubst (t, args, tf_error, NULL_TREE);
8369 if (TREE_CODE (t) == TEMPLATE_DECL)
8370 --processing_template_decl;
8371 set_current_access_from_decl (r);
8372 finish_member_declaration (r);
8376 /* Build new TYPE_FIELDS. */
8377 if (TREE_CODE (t) == STATIC_ASSERT)
8380 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8381 tf_warning_or_error, NULL_TREE,
8382 /*integral_constant_expression_p=*/true);
8383 finish_static_assert (condition,
8384 STATIC_ASSERT_MESSAGE (t),
8385 STATIC_ASSERT_SOURCE_LOCATION (t),
8388 else if (TREE_CODE (t) != CONST_DECL)
8392 /* The file and line for this declaration, to
8393 assist in error message reporting. Since we
8394 called push_tinst_level above, we don't need to
8396 input_location = DECL_SOURCE_LOCATION (t);
8398 if (TREE_CODE (t) == TEMPLATE_DECL)
8399 ++processing_template_decl;
8400 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8401 if (TREE_CODE (t) == TEMPLATE_DECL)
8402 --processing_template_decl;
8403 if (TREE_CODE (r) == VAR_DECL)
8407 [t]he initialization (and any associated
8408 side-effects) of a static data member does
8409 not occur unless the static data member is
8410 itself used in a way that requires the
8411 definition of the static data member to
8414 Therefore, we do not substitute into the
8415 initialized for the static data member here. */
8416 finish_static_data_member_decl
8419 /*init_const_expr_p=*/false,
8420 /*asmspec_tree=*/NULL_TREE,
8423 else if (TREE_CODE (r) == FIELD_DECL)
8425 /* Determine whether R has a valid type and can be
8426 completed later. If R is invalid, then it is
8427 replaced by error_mark_node so that it will not be
8428 added to TYPE_FIELDS. */
8429 tree rtype = TREE_TYPE (r);
8430 if (can_complete_type_without_circularity (rtype))
8431 complete_type (rtype);
8433 if (!COMPLETE_TYPE_P (rtype))
8435 cxx_incomplete_type_error (r, rtype);
8436 r = error_mark_node;
8440 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8441 such a thing will already have been added to the field
8442 list by tsubst_enum in finish_member_declaration in the
8443 CLASSTYPE_NESTED_UTDS case above. */
8444 if (!(TREE_CODE (r) == TYPE_DECL
8445 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8446 && DECL_ARTIFICIAL (r)))
8448 set_current_access_from_decl (r);
8449 finish_member_declaration (r);
8456 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8458 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8460 tree friend_type = t;
8461 bool adjust_processing_template_decl = false;
8463 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8465 /* template <class T> friend class C; */
8466 friend_type = tsubst_friend_class (friend_type, args);
8467 adjust_processing_template_decl = true;
8469 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8471 /* template <class T> friend class C::D; */
8472 friend_type = tsubst (friend_type, args,
8473 tf_warning_or_error, NULL_TREE);
8474 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8475 friend_type = TREE_TYPE (friend_type);
8476 adjust_processing_template_decl = true;
8478 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8479 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8481 /* This could be either
8485 when dependent_type_p is false or
8487 template <class U> friend class T::C;
8490 friend_type = tsubst (friend_type, args,
8491 tf_warning_or_error, NULL_TREE);
8492 /* Bump processing_template_decl for correct
8493 dependent_type_p calculation. */
8494 ++processing_template_decl;
8495 if (dependent_type_p (friend_type))
8496 adjust_processing_template_decl = true;
8497 --processing_template_decl;
8499 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8500 && hidden_name_p (TYPE_NAME (friend_type)))
8504 where C hasn't been declared yet. Let's lookup name
8505 from namespace scope directly, bypassing any name that
8506 come from dependent base class. */
8507 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8509 /* The call to xref_tag_from_type does injection for friend
8511 push_nested_namespace (ns);
8513 xref_tag_from_type (friend_type, NULL_TREE,
8514 /*tag_scope=*/ts_current);
8515 pop_nested_namespace (ns);
8517 else if (uses_template_parms (friend_type))
8518 /* friend class C<T>; */
8519 friend_type = tsubst (friend_type, args,
8520 tf_warning_or_error, NULL_TREE);
8525 where C is already declared or
8527 friend class C<int>;
8529 We don't have to do anything in these cases. */
8531 if (adjust_processing_template_decl)
8532 /* Trick make_friend_class into realizing that the friend
8533 we're adding is a template, not an ordinary class. It's
8534 important that we use make_friend_class since it will
8535 perform some error-checking and output cross-reference
8537 ++processing_template_decl;
8539 if (friend_type != error_mark_node)
8540 make_friend_class (type, friend_type, /*complain=*/false);
8542 if (adjust_processing_template_decl)
8543 --processing_template_decl;
8547 /* Build new DECL_FRIENDLIST. */
8550 /* The file and line for this declaration, to
8551 assist in error message reporting. Since we
8552 called push_tinst_level above, we don't need to
8554 input_location = DECL_SOURCE_LOCATION (t);
8556 if (TREE_CODE (t) == TEMPLATE_DECL)
8558 ++processing_template_decl;
8559 push_deferring_access_checks (dk_no_check);
8562 r = tsubst_friend_function (t, args);
8563 add_friend (type, r, /*complain=*/false);
8564 if (TREE_CODE (t) == TEMPLATE_DECL)
8566 pop_deferring_access_checks ();
8567 --processing_template_decl;
8573 if (CLASSTYPE_LAMBDA_EXPR (type))
8574 maybe_add_lambda_conv_op (type);
8576 /* Set the file and line number information to whatever is given for
8577 the class itself. This puts error messages involving generated
8578 implicit functions at a predictable point, and the same point
8579 that would be used for non-template classes. */
8580 input_location = DECL_SOURCE_LOCATION (typedecl);
8582 unreverse_member_declarations (type);
8583 finish_struct_1 (type);
8584 TYPE_BEING_DEFINED (type) = 0;
8586 /* We don't instantiate default arguments for member functions. 14.7.1:
8588 The implicit instantiation of a class template specialization causes
8589 the implicit instantiation of the declarations, but not of the
8590 definitions or default arguments, of the class member functions,
8591 member classes, static data members and member templates.... */
8593 /* Some typedefs referenced from within the template code need to be access
8594 checked at template instantiation time, i.e now. These types were
8595 added to the template at parsing time. Let's get those and perform
8596 the access checks then. */
8597 perform_typedefs_access_check (pattern, args);
8598 perform_deferred_access_checks ();
8599 pop_nested_class ();
8600 maximum_field_alignment = saved_maximum_field_alignment;
8601 pop_from_top_level ();
8602 pop_deferring_access_checks ();
8605 /* The vtable for a template class can be emitted in any translation
8606 unit in which the class is instantiated. When there is no key
8607 method, however, finish_struct_1 will already have added TYPE to
8608 the keyed_classes list. */
8609 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8610 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8615 /* Wrapper for instantiate_class_template_1. */
8618 instantiate_class_template (tree type)
8621 timevar_push (TV_TEMPLATE_INST);
8622 ret = instantiate_class_template_1 (type);
8623 timevar_pop (TV_TEMPLATE_INST);
8628 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8634 else if (TYPE_P (t))
8635 r = tsubst (t, args, complain, in_decl);
8638 if (!(complain & tf_warning))
8639 ++c_inhibit_evaluation_warnings;
8640 r = tsubst_expr (t, args, complain, in_decl,
8641 /*integral_constant_expression_p=*/true);
8642 if (!(complain & tf_warning))
8643 --c_inhibit_evaluation_warnings;
8648 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8649 NONTYPE_ARGUMENT_PACK. */
8652 make_fnparm_pack (tree spec_parm)
8654 /* Collect all of the extra "packed" parameters into an
8658 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8659 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8660 int i, len = list_length (spec_parm);
8662 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8663 parmvec = make_tree_vec (len);
8664 parmtypevec = make_tree_vec (len);
8665 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8667 TREE_VEC_ELT (parmvec, i) = spec_parm;
8668 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8671 /* Build the argument packs. */
8672 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8673 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8674 TREE_TYPE (argpack) = argtypepack;
8679 /* Substitute ARGS into T, which is an pack expansion
8680 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8681 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8682 (if only a partial substitution could be performed) or
8683 ERROR_MARK_NODE if there was an error. */
8685 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8689 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8693 htab_t saved_local_specializations = NULL;
8695 gcc_assert (PACK_EXPANSION_P (t));
8696 pattern = PACK_EXPANSION_PATTERN (t);
8698 /* Determine the argument packs that will instantiate the parameter
8699 packs used in the expansion expression. While we're at it,
8700 compute the number of arguments to be expanded and make sure it
8702 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8703 pack = TREE_CHAIN (pack))
8705 tree parm_pack = TREE_VALUE (pack);
8706 tree arg_pack = NULL_TREE;
8707 tree orig_arg = NULL_TREE;
8709 if (TREE_CODE (parm_pack) == PARM_DECL)
8711 if (!cp_unevaluated_operand)
8712 arg_pack = retrieve_local_specialization (parm_pack);
8715 /* We can't rely on local_specializations for a parameter
8716 name used later in a function declaration (such as in a
8717 late-specified return type). Even if it exists, it might
8718 have the wrong value for a recursive call. Just make a
8719 dummy decl, since it's only used for its type. */
8720 arg_pack = tsubst_decl (parm_pack, args, complain);
8721 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
8722 /* Partial instantiation of the parm_pack, we can't build
8723 up an argument pack yet. */
8724 arg_pack = NULL_TREE;
8726 arg_pack = make_fnparm_pack (arg_pack);
8731 int level, idx, levels;
8732 template_parm_level_and_index (parm_pack, &level, &idx);
8734 levels = TMPL_ARGS_DEPTH (args);
8735 if (level <= levels)
8736 arg_pack = TMPL_ARG (args, level, idx);
8739 orig_arg = arg_pack;
8740 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8741 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8743 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8744 /* This can only happen if we forget to expand an argument
8745 pack somewhere else. Just return an error, silently. */
8747 result = make_tree_vec (1);
8748 TREE_VEC_ELT (result, 0) = error_mark_node;
8752 /* For clarity in the comments below let's use the
8753 representation 'argument_pack<elements>' to denote an
8754 argument pack and its elements.
8756 In the 'if' block below, we want to detect cases where
8757 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
8758 check if ARG_PACK is an argument pack which sole element is
8759 the expansion of PARM_PACK. That argument pack is typically
8760 created by template_parm_to_arg when passed a parameter
8763 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8764 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8766 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8767 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8768 /* So we have an argument_pack<P...>. We want to test if P
8769 is actually PARM_PACK. We will not use cp_tree_equal to
8770 test P and PARM_PACK because during type fixup (by
8771 fixup_template_parm) P can be a pre-fixup version of a
8772 type and PARM_PACK be its post-fixup version.
8773 cp_tree_equal would consider them as different even
8774 though we would want to consider them compatible for our
8775 precise purpose here.
8777 Thus we are going to consider that P and PARM_PACK are
8778 compatible if they have the same DECL. */
8779 if ((/* If ARG_PACK is a type parameter pack named by the
8780 same DECL as parm_pack ... */
8782 && TYPE_P (parm_pack)
8783 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
8784 /* ... or if ARG_PACK is a non-type parameter
8785 named by the same DECL as parm_pack ... */
8786 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
8787 && TREE_CODE (parm_pack) == PARM_DECL
8788 && TEMPLATE_PARM_DECL (pattern)
8789 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
8790 && template_parameter_pack_p (pattern))
8791 /* ... then the argument pack that the parameter maps to
8792 is just an expansion of the parameter itself, such as
8793 one would find in the implicit typedef of a class
8794 inside the class itself. Consider this parameter
8795 "unsubstituted", so that we will maintain the outer
8797 arg_pack = NULL_TREE;
8803 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8805 /* It's all-or-nothing with incomplete argument packs. */
8806 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8807 return error_mark_node;
8809 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8814 else if (len != my_len)
8817 /* We got explicit args for some packs but not others;
8818 do nothing now and try again after deduction. */
8820 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8821 error ("mismatched argument pack lengths while expanding "
8825 error ("mismatched argument pack lengths while expanding "
8828 return error_mark_node;
8831 /* Keep track of the parameter packs and their corresponding
8833 packs = tree_cons (parm_pack, arg_pack, packs);
8834 TREE_TYPE (packs) = orig_arg;
8837 /* We can't substitute for this parameter pack. */
8838 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8840 unsubstituted_packs);
8843 /* We cannot expand this expansion expression, because we don't have
8844 all of the argument packs we need. Substitute into the pattern
8845 and return a PACK_EXPANSION_*. The caller will need to deal with
8847 if (unsubstituted_packs)
8850 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8851 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8852 /*integral_constant_expression_p=*/false);
8854 new_pat = tsubst (pattern, args, complain, in_decl);
8855 return make_pack_expansion (new_pat);
8858 /* We could not find any argument packs that work. */
8860 return error_mark_node;
8862 if (cp_unevaluated_operand)
8864 /* We're in a late-specified return type, so create our own local
8865 specializations table; the current table is either NULL or (in the
8866 case of recursive unification) might have bindings that we don't
8867 want to use or alter. */
8868 saved_local_specializations = local_specializations;
8869 local_specializations = htab_create (37,
8870 hash_local_specialization,
8871 eq_local_specializations,
8875 /* For each argument in each argument pack, substitute into the
8877 result = make_tree_vec (len + incomplete);
8878 for (i = 0; i < len + incomplete; ++i)
8880 /* For parameter pack, change the substitution of the parameter
8881 pack to the ith argument in its argument pack, then expand
8883 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8885 tree parm = TREE_PURPOSE (pack);
8887 if (TREE_CODE (parm) == PARM_DECL)
8889 /* Select the Ith argument from the pack. */
8890 tree arg = make_node (ARGUMENT_PACK_SELECT);
8891 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8892 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8894 register_local_specialization (arg, parm);
8900 template_parm_level_and_index (parm, &level, &idx);
8904 /* Select the Ith argument from the pack. */
8905 value = make_node (ARGUMENT_PACK_SELECT);
8906 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8907 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8910 /* Update the corresponding argument. */
8911 TMPL_ARG (args, level, idx) = value;
8915 /* Substitute into the PATTERN with the altered arguments. */
8916 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8917 TREE_VEC_ELT (result, i) =
8918 tsubst_expr (pattern, args, complain, in_decl,
8919 /*integral_constant_expression_p=*/false);
8921 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8924 /* When we have incomplete argument packs, the last "expanded"
8925 result is itself a pack expansion, which allows us
8926 to deduce more arguments. */
8927 TREE_VEC_ELT (result, i) =
8928 make_pack_expansion (TREE_VEC_ELT (result, i));
8930 if (TREE_VEC_ELT (result, i) == error_mark_node)
8932 result = error_mark_node;
8937 /* Update ARGS to restore the substitution from parameter packs to
8938 their argument packs. */
8939 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8941 tree parm = TREE_PURPOSE (pack);
8943 if (TREE_CODE (parm) == PARM_DECL)
8944 register_local_specialization (TREE_TYPE (pack), parm);
8948 template_parm_level_and_index (parm, &level, &idx);
8950 /* Update the corresponding argument. */
8951 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8952 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8955 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8959 if (saved_local_specializations)
8961 htab_delete (local_specializations);
8962 local_specializations = saved_local_specializations;
8968 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8969 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8970 parameter packs; all parms generated from a function parameter pack will
8971 have the same DECL_PARM_INDEX. */
8974 get_pattern_parm (tree parm, tree tmpl)
8976 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8979 if (DECL_ARTIFICIAL (parm))
8981 for (patparm = DECL_ARGUMENTS (pattern);
8982 patparm; patparm = DECL_CHAIN (patparm))
8983 if (DECL_ARTIFICIAL (patparm)
8984 && DECL_NAME (parm) == DECL_NAME (patparm))
8989 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8990 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8991 gcc_assert (DECL_PARM_INDEX (patparm)
8992 == DECL_PARM_INDEX (parm));
8998 /* Substitute ARGS into the vector or list of template arguments T. */
9001 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9004 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9007 if (t == error_mark_node)
9008 return error_mark_node;
9010 len = TREE_VEC_LENGTH (t);
9011 elts = XALLOCAVEC (tree, len);
9013 for (i = 0; i < len; i++)
9015 tree orig_arg = TREE_VEC_ELT (t, i);
9018 if (TREE_CODE (orig_arg) == TREE_VEC)
9019 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9020 else if (PACK_EXPANSION_P (orig_arg))
9022 /* Substitute into an expansion expression. */
9023 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9025 if (TREE_CODE (new_arg) == TREE_VEC)
9026 /* Add to the expanded length adjustment the number of
9027 expanded arguments. We subtract one from this
9028 measurement, because the argument pack expression
9029 itself is already counted as 1 in
9030 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9031 the argument pack is empty. */
9032 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9034 else if (ARGUMENT_PACK_P (orig_arg))
9036 /* Substitute into each of the arguments. */
9037 new_arg = TYPE_P (orig_arg)
9038 ? cxx_make_type (TREE_CODE (orig_arg))
9039 : make_node (TREE_CODE (orig_arg));
9041 SET_ARGUMENT_PACK_ARGS (
9043 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9044 args, complain, in_decl));
9046 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9047 new_arg = error_mark_node;
9049 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9050 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9052 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9054 if (TREE_TYPE (new_arg) == error_mark_node)
9055 new_arg = error_mark_node;
9059 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9061 if (new_arg == error_mark_node)
9062 return error_mark_node;
9065 if (new_arg != orig_arg)
9072 /* Make space for the expanded arguments coming from template
9074 t = make_tree_vec (len + expanded_len_adjust);
9075 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9076 arguments for a member template.
9077 In that case each TREE_VEC in ORIG_T represents a level of template
9078 arguments, and ORIG_T won't carry any non defaulted argument count.
9079 It will rather be the nested TREE_VECs that will carry one.
9080 In other words, ORIG_T carries a non defaulted argument count only
9081 if it doesn't contain any nested TREE_VEC. */
9082 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9084 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9085 count += expanded_len_adjust;
9086 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9088 for (i = 0, out = 0; i < len; i++)
9090 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9091 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9092 && TREE_CODE (elts[i]) == TREE_VEC)
9096 /* Now expand the template argument pack "in place". */
9097 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9098 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9102 TREE_VEC_ELT (t, out) = elts[i];
9110 /* Return the result of substituting ARGS into the template parameters
9111 given by PARMS. If there are m levels of ARGS and m + n levels of
9112 PARMS, then the result will contain n levels of PARMS. For
9113 example, if PARMS is `template <class T> template <class U>
9114 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9115 result will be `template <int*, double, class V>'. */
9118 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9123 /* When substituting into a template, we must set
9124 PROCESSING_TEMPLATE_DECL as the template parameters may be
9125 dependent if they are based on one-another, and the dependency
9126 predicates are short-circuit outside of templates. */
9127 ++processing_template_decl;
9129 for (new_parms = &r;
9130 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9131 new_parms = &(TREE_CHAIN (*new_parms)),
9132 parms = TREE_CHAIN (parms))
9135 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9138 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9142 if (parms == error_mark_node)
9145 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9147 if (tuple == error_mark_node)
9150 TREE_VEC_ELT (new_vec, i) =
9151 tsubst_template_parm (tuple, args, complain);
9155 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9156 - TMPL_ARGS_DEPTH (args)),
9157 new_vec, NULL_TREE);
9160 --processing_template_decl;
9165 /* Return the result of substituting ARGS into one template parameter
9166 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9167 parameter and which TREE_PURPOSE is the default argument of the
9168 template parameter. */
9171 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9173 tree default_value, parm_decl;
9175 if (args == NULL_TREE
9177 || t == error_mark_node)
9180 gcc_assert (TREE_CODE (t) == TREE_LIST);
9182 default_value = TREE_PURPOSE (t);
9183 parm_decl = TREE_VALUE (t);
9185 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9186 if (TREE_CODE (parm_decl) == PARM_DECL
9187 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9188 parm_decl = error_mark_node;
9189 default_value = tsubst_template_arg (default_value, args,
9190 complain, NULL_TREE);
9192 return build_tree_list (default_value, parm_decl);
9195 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9196 type T. If T is not an aggregate or enumeration type, it is
9197 handled as if by tsubst. IN_DECL is as for tsubst. If
9198 ENTERING_SCOPE is nonzero, T is the context for a template which
9199 we are presently tsubst'ing. Return the substituted value. */
9202 tsubst_aggr_type (tree t,
9204 tsubst_flags_t complain,
9211 switch (TREE_CODE (t))
9214 if (TYPE_PTRMEMFUNC_P (t))
9215 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9217 /* Else fall through. */
9220 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9225 int saved_unevaluated_operand;
9226 int saved_inhibit_evaluation_warnings;
9228 /* In "sizeof(X<I>)" we need to evaluate "I". */
9229 saved_unevaluated_operand = cp_unevaluated_operand;
9230 cp_unevaluated_operand = 0;
9231 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9232 c_inhibit_evaluation_warnings = 0;
9234 /* First, determine the context for the type we are looking
9236 context = TYPE_CONTEXT (t);
9239 context = tsubst_aggr_type (context, args, complain,
9240 in_decl, /*entering_scope=*/1);
9241 /* If context is a nested class inside a class template,
9242 it may still need to be instantiated (c++/33959). */
9243 if (TYPE_P (context))
9244 context = complete_type (context);
9247 /* Then, figure out what arguments are appropriate for the
9248 type we are trying to find. For example, given:
9250 template <class T> struct S;
9251 template <class T, class U> void f(T, U) { S<U> su; }
9253 and supposing that we are instantiating f<int, double>,
9254 then our ARGS will be {int, double}, but, when looking up
9255 S we only want {double}. */
9256 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9258 if (argvec == error_mark_node)
9259 r = error_mark_node;
9262 r = lookup_template_class (t, argvec, in_decl, context,
9263 entering_scope, complain);
9264 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9267 cp_unevaluated_operand = saved_unevaluated_operand;
9268 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9273 /* This is not a template type, so there's nothing to do. */
9277 return tsubst (t, args, complain, in_decl);
9281 /* Substitute into the default argument ARG (a default argument for
9282 FN), which has the indicated TYPE. */
9285 tsubst_default_argument (tree fn, tree type, tree arg)
9287 tree saved_class_ptr = NULL_TREE;
9288 tree saved_class_ref = NULL_TREE;
9290 /* This can happen in invalid code. */
9291 if (TREE_CODE (arg) == DEFAULT_ARG)
9294 /* This default argument came from a template. Instantiate the
9295 default argument here, not in tsubst. In the case of
9304 we must be careful to do name lookup in the scope of S<T>,
9305 rather than in the current class. */
9306 push_access_scope (fn);
9307 /* The "this" pointer is not valid in a default argument. */
9310 saved_class_ptr = current_class_ptr;
9311 cp_function_chain->x_current_class_ptr = NULL_TREE;
9312 saved_class_ref = current_class_ref;
9313 cp_function_chain->x_current_class_ref = NULL_TREE;
9316 push_deferring_access_checks(dk_no_deferred);
9317 /* The default argument expression may cause implicitly defined
9318 member functions to be synthesized, which will result in garbage
9319 collection. We must treat this situation as if we were within
9320 the body of function so as to avoid collecting live data on the
9323 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9324 tf_warning_or_error, NULL_TREE,
9325 /*integral_constant_expression_p=*/false);
9327 pop_deferring_access_checks();
9329 /* Restore the "this" pointer. */
9332 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9333 cp_function_chain->x_current_class_ref = saved_class_ref;
9336 /* Make sure the default argument is reasonable. */
9337 arg = check_default_argument (type, arg);
9339 pop_access_scope (fn);
9344 /* Substitute into all the default arguments for FN. */
9347 tsubst_default_arguments (tree fn)
9352 tmpl_args = DECL_TI_ARGS (fn);
9354 /* If this function is not yet instantiated, we certainly don't need
9355 its default arguments. */
9356 if (uses_template_parms (tmpl_args))
9358 /* Don't do this again for clones. */
9359 if (DECL_CLONED_FUNCTION_P (fn))
9362 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9364 arg = TREE_CHAIN (arg))
9365 if (TREE_PURPOSE (arg))
9366 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9368 TREE_PURPOSE (arg));
9371 /* Substitute the ARGS into the T, which is a _DECL. Return the
9372 result of the substitution. Issue error and warning messages under
9373 control of COMPLAIN. */
9376 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9378 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9379 location_t saved_loc;
9384 /* Set the filename and linenumber to improve error-reporting. */
9385 saved_loc = input_location;
9386 input_location = DECL_SOURCE_LOCATION (t);
9388 switch (TREE_CODE (t))
9392 /* We can get here when processing a member function template,
9393 member class template, or template template parameter. */
9394 tree decl = DECL_TEMPLATE_RESULT (t);
9399 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9401 /* Template template parameter is treated here. */
9402 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9403 if (new_type == error_mark_node)
9404 RETURN (error_mark_node);
9407 DECL_CHAIN (r) = NULL_TREE;
9408 TREE_TYPE (r) = new_type;
9409 DECL_TEMPLATE_RESULT (r)
9410 = build_decl (DECL_SOURCE_LOCATION (decl),
9411 TYPE_DECL, DECL_NAME (decl), new_type);
9412 DECL_TEMPLATE_PARMS (r)
9413 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9415 TYPE_NAME (new_type) = r;
9419 /* We might already have an instance of this template.
9420 The ARGS are for the surrounding class type, so the
9421 full args contain the tsubst'd args for the context,
9422 plus the innermost args from the template decl. */
9423 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9424 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9425 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9426 /* Because this is a template, the arguments will still be
9427 dependent, even after substitution. If
9428 PROCESSING_TEMPLATE_DECL is not set, the dependency
9429 predicates will short-circuit. */
9430 ++processing_template_decl;
9431 full_args = tsubst_template_args (tmpl_args, args,
9433 --processing_template_decl;
9434 if (full_args == error_mark_node)
9435 RETURN (error_mark_node);
9437 /* If this is a default template template argument,
9438 tsubst might not have changed anything. */
9439 if (full_args == tmpl_args)
9442 hash = hash_tmpl_and_args (t, full_args);
9443 spec = retrieve_specialization (t, full_args, hash);
9444 if (spec != NULL_TREE)
9450 /* Make a new template decl. It will be similar to the
9451 original, but will record the current template arguments.
9452 We also create a new function declaration, which is just
9453 like the old one, but points to this new template, rather
9454 than the old one. */
9456 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9457 DECL_CHAIN (r) = NULL_TREE;
9459 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9461 if (TREE_CODE (decl) == TYPE_DECL)
9464 ++processing_template_decl;
9465 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9466 --processing_template_decl;
9467 if (new_type == error_mark_node)
9468 RETURN (error_mark_node);
9470 TREE_TYPE (r) = new_type;
9471 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9472 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9473 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9474 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9479 ++processing_template_decl;
9480 new_decl = tsubst (decl, args, complain, in_decl);
9481 --processing_template_decl;
9482 if (new_decl == error_mark_node)
9483 RETURN (error_mark_node);
9485 DECL_TEMPLATE_RESULT (r) = new_decl;
9486 DECL_TI_TEMPLATE (new_decl) = r;
9487 TREE_TYPE (r) = TREE_TYPE (new_decl);
9488 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9489 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9492 SET_DECL_IMPLICIT_INSTANTIATION (r);
9493 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9494 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9496 /* The template parameters for this new template are all the
9497 template parameters for the old template, except the
9498 outermost level of parameters. */
9499 DECL_TEMPLATE_PARMS (r)
9500 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9503 if (PRIMARY_TEMPLATE_P (t))
9504 DECL_PRIMARY_TEMPLATE (r) = r;
9506 if (TREE_CODE (decl) != TYPE_DECL)
9507 /* Record this non-type partial instantiation. */
9508 register_specialization (r, t,
9509 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9517 tree argvec = NULL_TREE;
9525 /* Nobody should be tsubst'ing into non-template functions. */
9526 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9528 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9533 /* If T is not dependent, just return it. We have to
9534 increment PROCESSING_TEMPLATE_DECL because
9535 value_dependent_expression_p assumes that nothing is
9536 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9537 ++processing_template_decl;
9538 dependent_p = value_dependent_expression_p (t);
9539 --processing_template_decl;
9543 /* Calculate the most general template of which R is a
9544 specialization, and the complete set of arguments used to
9546 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9547 argvec = tsubst_template_args (DECL_TI_ARGS
9548 (DECL_TEMPLATE_RESULT
9549 (DECL_TI_TEMPLATE (t))),
9550 args, complain, in_decl);
9551 if (argvec == error_mark_node)
9552 RETURN (error_mark_node);
9554 /* Check to see if we already have this specialization. */
9555 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9556 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9564 /* We can see more levels of arguments than parameters if
9565 there was a specialization of a member template, like
9568 template <class T> struct S { template <class U> void f(); }
9569 template <> template <class U> void S<int>::f(U);
9571 Here, we'll be substituting into the specialization,
9572 because that's where we can find the code we actually
9573 want to generate, but we'll have enough arguments for
9574 the most general template.
9576 We also deal with the peculiar case:
9578 template <class T> struct S {
9579 template <class U> friend void f();
9581 template <class U> void f() {}
9583 template void f<double>();
9585 Here, the ARGS for the instantiation of will be {int,
9586 double}. But, we only need as many ARGS as there are
9587 levels of template parameters in CODE_PATTERN. We are
9588 careful not to get fooled into reducing the ARGS in
9591 template <class T> struct S { template <class U> void f(U); }
9592 template <class T> template <> void S<T>::f(int) {}
9594 which we can spot because the pattern will be a
9595 specialization in this case. */
9596 args_depth = TMPL_ARGS_DEPTH (args);
9598 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9599 if (args_depth > parms_depth
9600 && !DECL_TEMPLATE_SPECIALIZATION (t))
9601 args = get_innermost_template_args (args, parms_depth);
9605 /* This special case arises when we have something like this:
9607 template <class T> struct S {
9608 friend void f<int>(int, double);
9611 Here, the DECL_TI_TEMPLATE for the friend declaration
9612 will be an IDENTIFIER_NODE. We are being called from
9613 tsubst_friend_function, and we want only to create a
9614 new decl (R) with appropriate types so that we can call
9615 determine_specialization. */
9616 gen_tmpl = NULL_TREE;
9619 if (DECL_CLASS_SCOPE_P (t))
9621 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9625 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9626 complain, t, /*entering_scope=*/1);
9631 ctx = DECL_CONTEXT (t);
9633 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9634 if (type == error_mark_node)
9635 RETURN (error_mark_node);
9637 /* We do NOT check for matching decls pushed separately at this
9638 point, as they may not represent instantiations of this
9639 template, and in any case are considered separate under the
9642 DECL_USE_TEMPLATE (r) = 0;
9643 TREE_TYPE (r) = type;
9644 /* Clear out the mangled name and RTL for the instantiation. */
9645 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9646 SET_DECL_RTL (r, NULL);
9647 /* Leave DECL_INITIAL set on deleted instantiations. */
9648 if (!DECL_DELETED_FN (r))
9649 DECL_INITIAL (r) = NULL_TREE;
9650 DECL_CONTEXT (r) = ctx;
9652 if (member && DECL_CONV_FN_P (r))
9653 /* Type-conversion operator. Reconstruct the name, in
9654 case it's the name of one of the template's parameters. */
9655 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9657 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9659 DECL_RESULT (r) = NULL_TREE;
9661 TREE_STATIC (r) = 0;
9662 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9663 DECL_EXTERNAL (r) = 1;
9664 /* If this is an instantiation of a function with internal
9665 linkage, we already know what object file linkage will be
9666 assigned to the instantiation. */
9667 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9668 DECL_DEFER_OUTPUT (r) = 0;
9669 DECL_CHAIN (r) = NULL_TREE;
9670 DECL_PENDING_INLINE_INFO (r) = 0;
9671 DECL_PENDING_INLINE_P (r) = 0;
9672 DECL_SAVED_TREE (r) = NULL_TREE;
9673 DECL_STRUCT_FUNCTION (r) = NULL;
9675 /* We'll re-clone as appropriate in instantiate_template. */
9676 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9678 /* If we aren't complaining now, return on error before we register
9679 the specialization so that we'll complain eventually. */
9680 if ((complain & tf_error) == 0
9681 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9682 && !grok_op_properties (r, /*complain=*/false))
9683 RETURN (error_mark_node);
9685 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9686 this in the special friend case mentioned above where
9687 GEN_TMPL is NULL. */
9690 DECL_TEMPLATE_INFO (r)
9691 = build_template_info (gen_tmpl, argvec);
9692 SET_DECL_IMPLICIT_INSTANTIATION (r);
9693 register_specialization (r, gen_tmpl, argvec, false, hash);
9695 /* We're not supposed to instantiate default arguments
9696 until they are called, for a template. But, for a
9699 template <class T> void f ()
9700 { extern void g(int i = T()); }
9702 we should do the substitution when the template is
9703 instantiated. We handle the member function case in
9704 instantiate_class_template since the default arguments
9705 might refer to other members of the class. */
9707 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9708 && !uses_template_parms (argvec))
9709 tsubst_default_arguments (r);
9712 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9714 /* Copy the list of befriending classes. */
9715 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9717 friends = &TREE_CHAIN (*friends))
9719 *friends = copy_node (*friends);
9720 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9725 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9727 maybe_retrofit_in_chrg (r);
9728 if (DECL_CONSTRUCTOR_P (r))
9729 grok_ctor_properties (ctx, r);
9730 /* If this is an instantiation of a member template, clone it.
9731 If it isn't, that'll be handled by
9732 clone_constructors_and_destructors. */
9733 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9734 clone_function_decl (r, /*update_method_vec_p=*/0);
9736 else if ((complain & tf_error) != 0
9737 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9738 && !grok_op_properties (r, /*complain=*/true))
9739 RETURN (error_mark_node);
9741 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9742 SET_DECL_FRIEND_CONTEXT (r,
9743 tsubst (DECL_FRIEND_CONTEXT (t),
9744 args, complain, in_decl));
9746 /* Possibly limit visibility based on template args. */
9747 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9748 if (DECL_VISIBILITY_SPECIFIED (t))
9750 DECL_VISIBILITY_SPECIFIED (r) = 0;
9752 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9754 determine_visibility (r);
9755 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9756 && !processing_template_decl)
9757 defaulted_late_check (r);
9759 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9760 args, complain, in_decl);
9766 tree type = NULL_TREE;
9768 tree expanded_types = NULL_TREE;
9769 tree prev_r = NULL_TREE;
9770 tree first_r = NULL_TREE;
9772 if (FUNCTION_PARAMETER_PACK_P (t))
9774 /* If there is a local specialization that isn't a
9775 parameter pack, it means that we're doing a "simple"
9776 substitution from inside tsubst_pack_expansion. Just
9777 return the local specialization (which will be a single
9779 tree spec = retrieve_local_specialization (t);
9781 && TREE_CODE (spec) == PARM_DECL
9782 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9785 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9786 the parameters in this function parameter pack. */
9787 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9789 if (TREE_CODE (expanded_types) == TREE_VEC)
9791 len = TREE_VEC_LENGTH (expanded_types);
9793 /* Zero-length parameter packs are boring. Just substitute
9796 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9801 /* All we did was update the type. Make a note of that. */
9802 type = expanded_types;
9803 expanded_types = NULL_TREE;
9807 /* Loop through all of the parameter's we'll build. When T is
9808 a function parameter pack, LEN is the number of expanded
9809 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9811 for (i = 0; i < len; ++i)
9815 if (DECL_TEMPLATE_PARM_P (t))
9816 SET_DECL_TEMPLATE_PARM_P (r);
9819 /* We're on the Ith parameter of the function parameter
9822 /* An argument of a function parameter pack is not a parameter
9824 FUNCTION_PARAMETER_PACK_P (r) = false;
9826 /* Get the Ith type. */
9827 type = TREE_VEC_ELT (expanded_types, i);
9830 /* Rename the parameter to include the index. */
9832 make_ith_pack_parameter_name (DECL_NAME (r), i);
9835 /* We're dealing with a normal parameter. */
9836 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9838 type = type_decays_to (type);
9839 TREE_TYPE (r) = type;
9840 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9842 if (DECL_INITIAL (r))
9844 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9845 DECL_INITIAL (r) = TREE_TYPE (r);
9847 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9851 DECL_CONTEXT (r) = NULL_TREE;
9853 if (!DECL_TEMPLATE_PARM_P (r))
9854 DECL_ARG_TYPE (r) = type_passed_as (type);
9856 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9857 args, complain, in_decl);
9859 /* Keep track of the first new parameter we
9860 generate. That's what will be returned to the
9865 /* Build a proper chain of parameters when substituting
9866 into a function parameter pack. */
9868 DECL_CHAIN (prev_r) = r;
9872 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9873 complain, DECL_CHAIN (t));
9875 /* FIRST_R contains the start of the chain we've built. */
9885 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9886 if (type == error_mark_node)
9887 RETURN (error_mark_node);
9888 TREE_TYPE (r) = type;
9889 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9891 /* DECL_INITIAL gives the number of bits in a bit-field. */
9893 = tsubst_expr (DECL_INITIAL (t), args,
9895 /*integral_constant_expression_p=*/true);
9896 /* We don't have to set DECL_CONTEXT here; it is set by
9897 finish_member_declaration. */
9898 DECL_CHAIN (r) = NULL_TREE;
9899 if (VOID_TYPE_P (type))
9900 error ("instantiation of %q+D as type %qT", r, type);
9902 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9903 args, complain, in_decl);
9908 /* We reach here only for member using decls. */
9909 if (DECL_DEPENDENT_P (t))
9911 r = do_class_using_decl
9912 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9913 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9915 r = error_mark_node;
9918 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9919 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9925 DECL_CHAIN (r) = NULL_TREE;
9932 tree argvec = NULL_TREE;
9933 tree gen_tmpl = NULL_TREE;
9935 tree tmpl = NULL_TREE;
9937 tree type = NULL_TREE;
9940 if (TREE_CODE (t) == TYPE_DECL
9941 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9943 /* If this is the canonical decl, we don't have to
9944 mess with instantiations, and often we can't (for
9945 typename, template type parms and such). Note that
9946 TYPE_NAME is not correct for the above test if
9947 we've copied the type for a typedef. */
9948 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9949 if (type == error_mark_node)
9950 RETURN (error_mark_node);
9951 r = TYPE_NAME (type);
9955 /* Check to see if we already have the specialization we
9958 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9960 /* T is a static data member or namespace-scope entity.
9961 We have to substitute into namespace-scope variables
9962 (even though such entities are never templates) because
9965 template <class T> void f() { extern T t; }
9967 where the entity referenced is not known until
9968 instantiation time. */
9970 ctx = DECL_CONTEXT (t);
9971 if (DECL_CLASS_SCOPE_P (t))
9973 ctx = tsubst_aggr_type (ctx, args,
9975 in_decl, /*entering_scope=*/1);
9976 /* If CTX is unchanged, then T is in fact the
9977 specialization we want. That situation occurs when
9978 referencing a static data member within in its own
9979 class. We can use pointer equality, rather than
9980 same_type_p, because DECL_CONTEXT is always
9982 if (ctx == DECL_CONTEXT (t))
9988 tmpl = DECL_TI_TEMPLATE (t);
9989 gen_tmpl = most_general_template (tmpl);
9990 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9991 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9992 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9997 /* A local variable. */
9999 /* Subsequent calls to pushdecl will fill this in. */
10001 spec = retrieve_local_specialization (t);
10003 /* If we already have the specialization we need, there is
10004 nothing more to do. */
10011 /* Create a new node for the specialization we need. */
10013 if (type == NULL_TREE)
10015 if (is_typedef_decl (t))
10016 type = DECL_ORIGINAL_TYPE (t);
10018 type = TREE_TYPE (t);
10019 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10020 type = strip_array_domain (type);
10021 type = tsubst (type, args, complain, in_decl);
10023 if (TREE_CODE (r) == VAR_DECL)
10025 /* Even if the original location is out of scope, the
10026 newly substituted one is not. */
10027 DECL_DEAD_FOR_LOCAL (r) = 0;
10028 DECL_INITIALIZED_P (r) = 0;
10029 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10030 if (type == error_mark_node)
10031 RETURN (error_mark_node);
10032 if (TREE_CODE (type) == FUNCTION_TYPE)
10034 /* It may seem that this case cannot occur, since:
10039 declares a function, not a variable. However:
10042 template <typename T> void g() { T t; }
10043 template void g<f>();
10045 is an attempt to declare a variable with function
10047 error ("variable %qD has function type",
10048 /* R is not yet sufficiently initialized, so we
10049 just use its name. */
10051 RETURN (error_mark_node);
10053 type = complete_type (type);
10054 /* Wait until cp_finish_decl to set this again, to handle
10055 circular dependency (template/instantiate6.C). */
10056 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10057 type = check_var_type (DECL_NAME (r), type);
10059 if (DECL_HAS_VALUE_EXPR_P (t))
10061 tree ve = DECL_VALUE_EXPR (t);
10062 ve = tsubst_expr (ve, args, complain, in_decl,
10063 /*constant_expression_p=*/false);
10064 SET_DECL_VALUE_EXPR (r, ve);
10067 else if (DECL_SELF_REFERENCE_P (t))
10068 SET_DECL_SELF_REFERENCE_P (r);
10069 TREE_TYPE (r) = type;
10070 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10071 DECL_CONTEXT (r) = ctx;
10072 /* Clear out the mangled name and RTL for the instantiation. */
10073 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10074 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10075 SET_DECL_RTL (r, NULL);
10076 /* The initializer must not be expanded until it is required;
10077 see [temp.inst]. */
10078 DECL_INITIAL (r) = NULL_TREE;
10079 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10080 SET_DECL_RTL (r, NULL);
10081 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10082 if (TREE_CODE (r) == VAR_DECL)
10084 /* Possibly limit visibility based on template args. */
10085 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10086 if (DECL_VISIBILITY_SPECIFIED (t))
10088 DECL_VISIBILITY_SPECIFIED (r) = 0;
10089 DECL_ATTRIBUTES (r)
10090 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10092 determine_visibility (r);
10097 /* A static data member declaration is always marked
10098 external when it is declared in-class, even if an
10099 initializer is present. We mimic the non-template
10100 processing here. */
10101 DECL_EXTERNAL (r) = 1;
10103 register_specialization (r, gen_tmpl, argvec, false, hash);
10104 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10105 SET_DECL_IMPLICIT_INSTANTIATION (r);
10107 else if (cp_unevaluated_operand)
10109 /* We're substituting this var in a decltype outside of its
10110 scope, such as for a lambda return type. Don't add it to
10111 local_specializations, do perform auto deduction. */
10112 tree auto_node = type_uses_auto (type);
10114 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10115 /*constant_expression_p=*/false);
10117 if (auto_node && init)
10119 init = resolve_nondeduced_context (init);
10120 if (describable_type (init))
10122 type = do_auto_deduction (type, init, auto_node);
10123 TREE_TYPE (r) = type;
10128 register_local_specialization (r, t);
10130 DECL_CHAIN (r) = NULL_TREE;
10132 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10134 args, complain, in_decl);
10136 /* Preserve a typedef that names a type. */
10137 if (is_typedef_decl (r))
10139 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10140 set_underlying_type (r);
10143 layout_decl (r, 0);
10148 gcc_unreachable ();
10153 /* Restore the file and line information. */
10154 input_location = saved_loc;
10159 /* Substitute into the ARG_TYPES of a function type. */
10162 tsubst_arg_types (tree arg_types,
10164 tsubst_flags_t complain,
10167 tree remaining_arg_types;
10168 tree type = NULL_TREE;
10170 tree expanded_args = NULL_TREE;
10173 if (!arg_types || arg_types == void_list_node)
10176 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10177 args, complain, in_decl);
10178 if (remaining_arg_types == error_mark_node)
10179 return error_mark_node;
10181 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10183 /* For a pack expansion, perform substitution on the
10184 entire expression. Later on, we'll handle the arguments
10186 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10187 args, complain, in_decl);
10189 if (TREE_CODE (expanded_args) == TREE_VEC)
10190 /* So that we'll spin through the parameters, one by one. */
10191 i = TREE_VEC_LENGTH (expanded_args);
10194 /* We only partially substituted into the parameter
10195 pack. Our type is TYPE_PACK_EXPANSION. */
10196 type = expanded_args;
10197 expanded_args = NULL_TREE;
10205 type = TREE_VEC_ELT (expanded_args, i);
10207 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10209 if (type == error_mark_node)
10210 return error_mark_node;
10211 if (VOID_TYPE_P (type))
10213 if (complain & tf_error)
10215 error ("invalid parameter type %qT", type);
10217 error ("in declaration %q+D", in_decl);
10219 return error_mark_node;
10222 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10223 top-level qualifiers as required. */
10224 type = TYPE_MAIN_VARIANT (type_decays_to (type));
10226 /* We do not substitute into default arguments here. The standard
10227 mandates that they be instantiated only when needed, which is
10228 done in build_over_call. */
10229 default_arg = TREE_PURPOSE (arg_types);
10231 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10233 /* We've instantiated a template before its default arguments
10234 have been parsed. This can happen for a nested template
10235 class, and is not an error unless we require the default
10236 argument in a call of this function. */
10237 remaining_arg_types =
10238 tree_cons (default_arg, type, remaining_arg_types);
10239 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10240 remaining_arg_types);
10243 remaining_arg_types =
10244 hash_tree_cons (default_arg, type, remaining_arg_types);
10247 return remaining_arg_types;
10250 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10251 *not* handle the exception-specification for FNTYPE, because the
10252 initial substitution of explicitly provided template parameters
10253 during argument deduction forbids substitution into the
10254 exception-specification:
10258 All references in the function type of the function template to the
10259 corresponding template parameters are replaced by the specified tem-
10260 plate argument values. If a substitution in a template parameter or
10261 in the function type of the function template results in an invalid
10262 type, type deduction fails. [Note: The equivalent substitution in
10263 exception specifications is done only when the function is instanti-
10264 ated, at which point a program is ill-formed if the substitution
10265 results in an invalid type.] */
10268 tsubst_function_type (tree t,
10270 tsubst_flags_t complain,
10277 /* The TYPE_CONTEXT is not used for function/method types. */
10278 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10280 /* Substitute the return type. */
10281 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10282 if (return_type == error_mark_node)
10283 return error_mark_node;
10284 /* The standard does not presently indicate that creation of a
10285 function type with an invalid return type is a deduction failure.
10286 However, that is clearly analogous to creating an array of "void"
10287 or a reference to a reference. This is core issue #486. */
10288 if (TREE_CODE (return_type) == ARRAY_TYPE
10289 || TREE_CODE (return_type) == FUNCTION_TYPE)
10291 if (complain & tf_error)
10293 if (TREE_CODE (return_type) == ARRAY_TYPE)
10294 error ("function returning an array");
10296 error ("function returning a function");
10298 return error_mark_node;
10301 /* Substitute the argument types. */
10302 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10303 complain, in_decl);
10304 if (arg_types == error_mark_node)
10305 return error_mark_node;
10307 /* Construct a new type node and return it. */
10308 if (TREE_CODE (t) == FUNCTION_TYPE)
10310 fntype = build_function_type (return_type, arg_types);
10311 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10315 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10316 if (! MAYBE_CLASS_TYPE_P (r))
10320 Type deduction may fail for any of the following
10323 -- Attempting to create "pointer to member of T" when T
10324 is not a class type. */
10325 if (complain & tf_error)
10326 error ("creating pointer to member function of non-class type %qT",
10328 return error_mark_node;
10331 fntype = build_method_type_directly (r, return_type,
10332 TREE_CHAIN (arg_types));
10334 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10339 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10340 ARGS into that specification, and return the substituted
10341 specification. If there is no specification, return NULL_TREE. */
10344 tsubst_exception_specification (tree fntype,
10346 tsubst_flags_t complain,
10353 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10354 new_specs = NULL_TREE;
10355 if (specs && TREE_PURPOSE (specs))
10357 /* A noexcept-specifier. */
10358 tree expr = TREE_PURPOSE (specs);
10359 if (expr == boolean_true_node || expr == boolean_false_node)
10363 /* Defer instantiation of noexcept-specifiers to avoid
10364 excessive instantiations (c++/49107). */
10365 new_specs = make_node (DEFERRED_NOEXCEPT);
10366 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
10368 /* We already partially instantiated this member template,
10369 so combine the new args with the old. */
10370 DEFERRED_NOEXCEPT_PATTERN (new_specs)
10371 = DEFERRED_NOEXCEPT_PATTERN (expr);
10372 DEFERRED_NOEXCEPT_ARGS (new_specs)
10373 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
10377 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
10378 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
10382 new_specs = tsubst_copy_and_build
10383 (expr, args, complain, in_decl, /*function_p=*/false,
10384 /*integral_constant_expression_p=*/true);
10385 new_specs = build_noexcept_spec (new_specs, complain);
10389 if (! TREE_VALUE (specs))
10396 tree expanded_specs = NULL_TREE;
10398 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10400 /* Expand the pack expansion type. */
10401 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10405 if (expanded_specs == error_mark_node)
10406 return error_mark_node;
10407 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10408 len = TREE_VEC_LENGTH (expanded_specs);
10411 /* We're substituting into a member template, so
10412 we got a TYPE_PACK_EXPANSION back. Add that
10413 expansion and move on. */
10414 gcc_assert (TREE_CODE (expanded_specs)
10415 == TYPE_PACK_EXPANSION);
10416 new_specs = add_exception_specifier (new_specs,
10419 specs = TREE_CHAIN (specs);
10424 for (i = 0; i < len; ++i)
10426 if (expanded_specs)
10427 spec = TREE_VEC_ELT (expanded_specs, i);
10429 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10430 if (spec == error_mark_node)
10432 new_specs = add_exception_specifier (new_specs, spec,
10436 specs = TREE_CHAIN (specs);
10442 /* Take the tree structure T and replace template parameters used
10443 therein with the argument vector ARGS. IN_DECL is an associated
10444 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10445 Issue error and warning messages under control of COMPLAIN. Note
10446 that we must be relatively non-tolerant of extensions here, in
10447 order to preserve conformance; if we allow substitutions that
10448 should not be allowed, we may allow argument deductions that should
10449 not succeed, and therefore report ambiguous overload situations
10450 where there are none. In theory, we could allow the substitution,
10451 but indicate that it should have failed, and allow our caller to
10452 make sure that the right thing happens, but we don't try to do this
10455 This function is used for dealing with types, decls and the like;
10456 for expressions, use tsubst_expr or tsubst_copy. */
10459 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10461 enum tree_code code;
10464 if (t == NULL_TREE || t == error_mark_node
10465 || t == integer_type_node
10466 || t == void_type_node
10467 || t == char_type_node
10468 || t == unknown_type_node
10469 || TREE_CODE (t) == NAMESPACE_DECL
10470 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10474 return tsubst_decl (t, args, complain);
10476 if (args == NULL_TREE)
10479 code = TREE_CODE (t);
10481 if (code == IDENTIFIER_NODE)
10482 type = IDENTIFIER_TYPE_VALUE (t);
10484 type = TREE_TYPE (t);
10486 gcc_assert (type != unknown_type_node);
10488 /* Reuse typedefs. We need to do this to handle dependent attributes,
10489 such as attribute aligned. */
10491 && typedef_variant_p (t))
10493 tree decl = TYPE_NAME (t);
10495 if (DECL_CLASS_SCOPE_P (decl)
10496 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10497 && uses_template_parms (DECL_CONTEXT (decl)))
10499 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10500 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10501 r = retrieve_specialization (tmpl, gen_args, 0);
10503 else if (DECL_FUNCTION_SCOPE_P (decl)
10504 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10505 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10506 r = retrieve_local_specialization (decl);
10508 /* The typedef is from a non-template context. */
10514 r = cp_build_qualified_type_real
10515 (r, cp_type_quals (t) | cp_type_quals (r),
10516 complain | tf_ignore_bad_quals);
10519 /* Else we must be instantiating the typedef, so fall through. */
10523 && code != TYPENAME_TYPE
10524 && code != TEMPLATE_TYPE_PARM
10525 && code != IDENTIFIER_NODE
10526 && code != FUNCTION_TYPE
10527 && code != METHOD_TYPE)
10528 type = tsubst (type, args, complain, in_decl);
10529 if (type == error_mark_node)
10530 return error_mark_node;
10536 case ENUMERAL_TYPE:
10537 return tsubst_aggr_type (t, args, complain, in_decl,
10538 /*entering_scope=*/0);
10541 case IDENTIFIER_NODE:
10552 if (t == integer_type_node)
10555 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10556 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10560 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10562 max = tsubst_expr (omax, args, complain, in_decl,
10563 /*integral_constant_expression_p=*/false);
10565 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10567 if (TREE_CODE (max) == NOP_EXPR
10568 && TREE_SIDE_EFFECTS (omax)
10569 && !TREE_TYPE (max))
10570 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10572 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10573 with TREE_SIDE_EFFECTS that indicates this is not an integral
10574 constant expression. */
10575 if (processing_template_decl
10576 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10578 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10579 TREE_SIDE_EFFECTS (max) = 1;
10582 return compute_array_index_type (NULL_TREE, max, complain);
10585 case TEMPLATE_TYPE_PARM:
10586 case TEMPLATE_TEMPLATE_PARM:
10587 case BOUND_TEMPLATE_TEMPLATE_PARM:
10588 case TEMPLATE_PARM_INDEX:
10593 tree arg = NULL_TREE;
10597 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10598 template_parm_level_and_index (t, &level, &idx);
10600 levels = TMPL_ARGS_DEPTH (args);
10601 if (level <= levels)
10603 arg = TMPL_ARG (args, level, idx);
10605 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10606 /* See through ARGUMENT_PACK_SELECT arguments. */
10607 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10610 if (arg == error_mark_node)
10611 return error_mark_node;
10612 else if (arg != NULL_TREE)
10614 if (ARGUMENT_PACK_P (arg))
10615 /* If ARG is an argument pack, we don't actually want to
10616 perform a substitution here, because substitutions
10617 for argument packs are only done
10618 element-by-element. We can get to this point when
10619 substituting the type of a non-type template
10620 parameter pack, when that type actually contains
10621 template parameter packs from an outer template, e.g.,
10623 template<typename... Types> struct A {
10624 template<Types... Values> struct B { };
10628 if (code == TEMPLATE_TYPE_PARM)
10631 gcc_assert (TYPE_P (arg));
10633 quals = cp_type_quals (arg) | cp_type_quals (t);
10635 return cp_build_qualified_type_real
10636 (arg, quals, complain | tf_ignore_bad_quals);
10638 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10640 /* We are processing a type constructed from a
10641 template template parameter. */
10642 tree argvec = tsubst (TYPE_TI_ARGS (t),
10643 args, complain, in_decl);
10644 if (argvec == error_mark_node)
10645 return error_mark_node;
10647 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10648 are resolving nested-types in the signature of a
10649 member function templates. Otherwise ARG is a
10650 TEMPLATE_DECL and is the real template to be
10652 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10653 arg = TYPE_NAME (arg);
10655 r = lookup_template_class (arg,
10657 DECL_CONTEXT (arg),
10658 /*entering_scope=*/0,
10660 return cp_build_qualified_type_real
10661 (r, cp_type_quals (t), complain);
10664 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10665 return unshare_expr (arg);
10669 /* This can happen during the attempted tsubst'ing in
10670 unify. This means that we don't yet have any information
10671 about the template parameter in question. */
10674 /* If we get here, we must have been looking at a parm for a
10675 more deeply nested template. Make a new version of this
10676 template parameter, but with a lower level. */
10679 case TEMPLATE_TYPE_PARM:
10680 case TEMPLATE_TEMPLATE_PARM:
10681 case BOUND_TEMPLATE_TEMPLATE_PARM:
10682 if (cp_type_quals (t))
10684 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10685 r = cp_build_qualified_type_real
10686 (r, cp_type_quals (t),
10687 complain | (code == TEMPLATE_TYPE_PARM
10688 ? tf_ignore_bad_quals : 0));
10693 TEMPLATE_TYPE_PARM_INDEX (r)
10694 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10695 r, levels, args, complain);
10696 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10697 TYPE_MAIN_VARIANT (r) = r;
10698 TYPE_POINTER_TO (r) = NULL_TREE;
10699 TYPE_REFERENCE_TO (r) = NULL_TREE;
10701 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10702 /* We have reduced the level of the template
10703 template parameter, but not the levels of its
10704 template parameters, so canonical_type_parameter
10705 will not be able to find the canonical template
10706 template parameter for this level. Thus, we
10707 require structural equality checking to compare
10708 TEMPLATE_TEMPLATE_PARMs. */
10709 SET_TYPE_STRUCTURAL_EQUALITY (r);
10710 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10711 SET_TYPE_STRUCTURAL_EQUALITY (r);
10713 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10715 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10717 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10718 complain, in_decl);
10719 if (argvec == error_mark_node)
10720 return error_mark_node;
10722 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10723 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10728 case TEMPLATE_PARM_INDEX:
10729 r = reduce_template_parm_level (t, type, levels, args, complain);
10733 gcc_unreachable ();
10741 tree purpose, value, chain;
10743 if (t == void_list_node)
10746 purpose = TREE_PURPOSE (t);
10749 purpose = tsubst (purpose, args, complain, in_decl);
10750 if (purpose == error_mark_node)
10751 return error_mark_node;
10753 value = TREE_VALUE (t);
10756 value = tsubst (value, args, complain, in_decl);
10757 if (value == error_mark_node)
10758 return error_mark_node;
10760 chain = TREE_CHAIN (t);
10761 if (chain && chain != void_type_node)
10763 chain = tsubst (chain, args, complain, in_decl);
10764 if (chain == error_mark_node)
10765 return error_mark_node;
10767 if (purpose == TREE_PURPOSE (t)
10768 && value == TREE_VALUE (t)
10769 && chain == TREE_CHAIN (t))
10771 return hash_tree_cons (purpose, value, chain);
10775 /* We should never be tsubsting a binfo. */
10776 gcc_unreachable ();
10779 /* A vector of template arguments. */
10780 gcc_assert (!type);
10781 return tsubst_template_args (t, args, complain, in_decl);
10784 case REFERENCE_TYPE:
10786 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10791 Type deduction may fail for any of the following
10794 -- Attempting to create a pointer to reference type.
10795 -- Attempting to create a reference to a reference type or
10796 a reference to void.
10798 Core issue 106 says that creating a reference to a reference
10799 during instantiation is no longer a cause for failure. We
10800 only enforce this check in strict C++98 mode. */
10801 if ((TREE_CODE (type) == REFERENCE_TYPE
10802 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10803 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10805 static location_t last_loc;
10807 /* We keep track of the last time we issued this error
10808 message to avoid spewing a ton of messages during a
10809 single bad template instantiation. */
10810 if (complain & tf_error
10811 && last_loc != input_location)
10813 if (TREE_CODE (type) == VOID_TYPE)
10814 error ("forming reference to void");
10815 else if (code == POINTER_TYPE)
10816 error ("forming pointer to reference type %qT", type);
10818 error ("forming reference to reference type %qT", type);
10819 last_loc = input_location;
10822 return error_mark_node;
10824 else if (code == POINTER_TYPE)
10826 r = build_pointer_type (type);
10827 if (TREE_CODE (type) == METHOD_TYPE)
10828 r = build_ptrmemfunc_type (r);
10830 else if (TREE_CODE (type) == REFERENCE_TYPE)
10831 /* In C++0x, during template argument substitution, when there is an
10832 attempt to create a reference to a reference type, reference
10833 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10835 "If a template-argument for a template-parameter T names a type
10836 that is a reference to a type A, an attempt to create the type
10837 'lvalue reference to cv T' creates the type 'lvalue reference to
10838 A,' while an attempt to create the type type rvalue reference to
10839 cv T' creates the type T"
10841 r = cp_build_reference_type
10843 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10845 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10846 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10848 if (r != error_mark_node)
10849 /* Will this ever be needed for TYPE_..._TO values? */
10856 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10857 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10861 Type deduction may fail for any of the following
10864 -- Attempting to create "pointer to member of T" when T
10865 is not a class type. */
10866 if (complain & tf_error)
10867 error ("creating pointer to member of non-class type %qT", r);
10868 return error_mark_node;
10870 if (TREE_CODE (type) == REFERENCE_TYPE)
10872 if (complain & tf_error)
10873 error ("creating pointer to member reference type %qT", type);
10874 return error_mark_node;
10876 if (TREE_CODE (type) == VOID_TYPE)
10878 if (complain & tf_error)
10879 error ("creating pointer to member of type void");
10880 return error_mark_node;
10882 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10883 if (TREE_CODE (type) == FUNCTION_TYPE)
10885 /* The type of the implicit object parameter gets its
10886 cv-qualifiers from the FUNCTION_TYPE. */
10888 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10889 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10890 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10894 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10898 case FUNCTION_TYPE:
10903 fntype = tsubst_function_type (t, args, complain, in_decl);
10904 if (fntype == error_mark_node)
10905 return error_mark_node;
10907 /* Substitute the exception specification. */
10908 specs = tsubst_exception_specification (t, args, complain,
10909 in_decl, /*defer_ok*/true);
10910 if (specs == error_mark_node)
10911 return error_mark_node;
10913 fntype = build_exception_variant (fntype, specs);
10918 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10919 if (domain == error_mark_node)
10920 return error_mark_node;
10922 /* As an optimization, we avoid regenerating the array type if
10923 it will obviously be the same as T. */
10924 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10927 /* These checks should match the ones in grokdeclarator.
10931 The deduction may fail for any of the following reasons:
10933 -- Attempting to create an array with an element type that
10934 is void, a function type, or a reference type, or [DR337]
10935 an abstract class type. */
10936 if (TREE_CODE (type) == VOID_TYPE
10937 || TREE_CODE (type) == FUNCTION_TYPE
10938 || TREE_CODE (type) == REFERENCE_TYPE)
10940 if (complain & tf_error)
10941 error ("creating array of %qT", type);
10942 return error_mark_node;
10944 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10946 if (complain & tf_error)
10947 error ("creating array of %qT, which is an abstract class type",
10949 return error_mark_node;
10952 r = build_cplus_array_type (type, domain);
10954 if (TYPE_USER_ALIGN (t))
10956 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10957 TYPE_USER_ALIGN (r) = 1;
10963 case TYPENAME_TYPE:
10965 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10966 in_decl, /*entering_scope=*/1);
10967 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10968 complain, in_decl);
10970 if (ctx == error_mark_node || f == error_mark_node)
10971 return error_mark_node;
10973 if (!MAYBE_CLASS_TYPE_P (ctx))
10975 if (complain & tf_error)
10976 error ("%qT is not a class, struct, or union type", ctx);
10977 return error_mark_node;
10979 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10981 /* Normally, make_typename_type does not require that the CTX
10982 have complete type in order to allow things like:
10984 template <class T> struct S { typename S<T>::X Y; };
10986 But, such constructs have already been resolved by this
10987 point, so here CTX really should have complete type, unless
10988 it's a partial instantiation. */
10989 ctx = complete_type (ctx);
10990 if (!COMPLETE_TYPE_P (ctx))
10992 if (complain & tf_error)
10993 cxx_incomplete_type_error (NULL_TREE, ctx);
10994 return error_mark_node;
10998 f = make_typename_type (ctx, f, typename_type,
10999 (complain & tf_error) | tf_keep_type_decl);
11000 if (f == error_mark_node)
11002 if (TREE_CODE (f) == TYPE_DECL)
11004 complain |= tf_ignore_bad_quals;
11008 if (TREE_CODE (f) != TYPENAME_TYPE)
11010 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11012 if (complain & tf_error)
11013 error ("%qT resolves to %qT, which is not an enumeration type",
11016 return error_mark_node;
11018 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11020 if (complain & tf_error)
11021 error ("%qT resolves to %qT, which is is not a class type",
11024 return error_mark_node;
11028 return cp_build_qualified_type_real
11029 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11032 case UNBOUND_CLASS_TEMPLATE:
11034 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11035 in_decl, /*entering_scope=*/1);
11036 tree name = TYPE_IDENTIFIER (t);
11037 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11039 if (ctx == error_mark_node || name == error_mark_node)
11040 return error_mark_node;
11043 parm_list = tsubst_template_parms (parm_list, args, complain);
11044 return make_unbound_class_template (ctx, name, parm_list, complain);
11051 ++cp_unevaluated_operand;
11052 ++c_inhibit_evaluation_warnings;
11054 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11056 /*integral_constant_expression_p=*/false);
11058 --cp_unevaluated_operand;
11059 --c_inhibit_evaluation_warnings;
11061 type = finish_typeof (type);
11062 return cp_build_qualified_type_real (type,
11064 | cp_type_quals (type),
11068 case DECLTYPE_TYPE:
11072 ++cp_unevaluated_operand;
11073 ++c_inhibit_evaluation_warnings;
11075 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11077 /*integral_constant_expression_p=*/false);
11079 --cp_unevaluated_operand;
11080 --c_inhibit_evaluation_warnings;
11082 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11083 type = lambda_capture_field_type (type);
11084 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
11085 type = lambda_return_type (type);
11087 type = finish_decltype_type
11088 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11089 return cp_build_qualified_type_real (type,
11091 | cp_type_quals (type),
11095 case UNDERLYING_TYPE:
11097 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11098 complain, in_decl);
11099 return finish_underlying_type (type);
11102 case TYPE_ARGUMENT_PACK:
11103 case NONTYPE_ARGUMENT_PACK:
11105 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11107 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11111 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11113 /* For template nontype argument packs, also substitute into
11115 if (code == NONTYPE_ARGUMENT_PACK)
11116 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11134 /* We should use one of the expression tsubsts for these codes. */
11135 gcc_unreachable ();
11138 sorry ("use of %qs in template", tree_code_name [(int) code]);
11139 return error_mark_node;
11143 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11144 type of the expression on the left-hand side of the "." or "->"
11148 tsubst_baselink (tree baselink, tree object_type,
11149 tree args, tsubst_flags_t complain, tree in_decl)
11152 tree qualifying_scope;
11155 tree template_args = 0;
11156 bool template_id_p = false;
11158 /* A baselink indicates a function from a base class. Both the
11159 BASELINK_ACCESS_BINFO and the base class referenced may
11160 indicate bases of the template class, rather than the
11161 instantiated class. In addition, lookups that were not
11162 ambiguous before may be ambiguous now. Therefore, we perform
11163 the lookup again. */
11164 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11165 qualifying_scope = tsubst (qualifying_scope, args,
11166 complain, in_decl);
11167 fns = BASELINK_FUNCTIONS (baselink);
11168 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11169 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11171 template_id_p = true;
11172 template_args = TREE_OPERAND (fns, 1);
11173 fns = TREE_OPERAND (fns, 0);
11175 template_args = tsubst_template_args (template_args, args,
11176 complain, in_decl);
11178 name = DECL_NAME (get_first_fn (fns));
11179 if (IDENTIFIER_TYPENAME_P (name))
11180 name = mangle_conv_op_name_for_type (optype);
11181 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11183 return error_mark_node;
11185 /* If lookup found a single function, mark it as used at this
11186 point. (If it lookup found multiple functions the one selected
11187 later by overload resolution will be marked as used at that
11189 if (BASELINK_P (baselink))
11190 fns = BASELINK_FUNCTIONS (baselink);
11191 if (!template_id_p && !really_overloaded_fn (fns))
11192 mark_used (OVL_CURRENT (fns));
11194 /* Add back the template arguments, if present. */
11195 if (BASELINK_P (baselink) && template_id_p)
11196 BASELINK_FUNCTIONS (baselink)
11197 = build_nt (TEMPLATE_ID_EXPR,
11198 BASELINK_FUNCTIONS (baselink),
11200 /* Update the conversion operator type. */
11201 BASELINK_OPTYPE (baselink) = optype;
11204 object_type = current_class_type;
11205 return adjust_result_of_qualified_name_lookup (baselink,
11210 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11211 true if the qualified-id will be a postfix-expression in-and-of
11212 itself; false if more of the postfix-expression follows the
11213 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11217 tsubst_qualified_id (tree qualified_id, tree args,
11218 tsubst_flags_t complain, tree in_decl,
11219 bool done, bool address_p)
11225 tree template_args;
11227 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11229 /* Figure out what name to look up. */
11230 name = TREE_OPERAND (qualified_id, 1);
11231 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11233 is_template = true;
11234 template_args = TREE_OPERAND (name, 1);
11236 template_args = tsubst_template_args (template_args, args,
11237 complain, in_decl);
11238 name = TREE_OPERAND (name, 0);
11242 is_template = false;
11243 template_args = NULL_TREE;
11246 /* Substitute into the qualifying scope. When there are no ARGS, we
11247 are just trying to simplify a non-dependent expression. In that
11248 case the qualifying scope may be dependent, and, in any case,
11249 substituting will not help. */
11250 scope = TREE_OPERAND (qualified_id, 0);
11253 scope = tsubst (scope, args, complain, in_decl);
11254 expr = tsubst_copy (name, args, complain, in_decl);
11259 if (dependent_scope_p (scope))
11260 return build_qualified_name (NULL_TREE, scope, expr,
11261 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11263 if (!BASELINK_P (name) && !DECL_P (expr))
11265 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11267 /* A BIT_NOT_EXPR is used to represent a destructor. */
11268 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11270 error ("qualifying type %qT does not match destructor name ~%qT",
11271 scope, TREE_OPERAND (expr, 0));
11272 expr = error_mark_node;
11275 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11276 /*is_type_p=*/0, false);
11279 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11280 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11281 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11283 if (complain & tf_error)
11285 error ("dependent-name %qE is parsed as a non-type, but "
11286 "instantiation yields a type", qualified_id);
11287 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11289 return error_mark_node;
11295 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11297 /* Remember that there was a reference to this entity. */
11301 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11303 if (complain & tf_error)
11304 qualified_name_lookup_error (scope,
11305 TREE_OPERAND (qualified_id, 1),
11306 expr, input_location);
11307 return error_mark_node;
11311 expr = lookup_template_function (expr, template_args);
11313 if (expr == error_mark_node && complain & tf_error)
11314 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11315 expr, input_location);
11316 else if (TYPE_P (scope))
11318 expr = (adjust_result_of_qualified_name_lookup
11319 (expr, scope, current_class_type));
11320 expr = (finish_qualified_id_expr
11321 (scope, expr, done, address_p,
11322 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11323 /*template_arg_p=*/false));
11326 /* Expressions do not generally have reference type. */
11327 if (TREE_CODE (expr) != SCOPE_REF
11328 /* However, if we're about to form a pointer-to-member, we just
11329 want the referenced member referenced. */
11330 && TREE_CODE (expr) != OFFSET_REF)
11331 expr = convert_from_reference (expr);
11336 /* Like tsubst, but deals with expressions. This function just replaces
11337 template parms; to finish processing the resultant expression, use
11341 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11343 enum tree_code code;
11346 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11349 code = TREE_CODE (t);
11354 r = retrieve_local_specialization (t);
11359 /* This can happen for a parameter name used later in a function
11360 declaration (such as in a late-specified return type). Just
11361 make a dummy decl, since it's only used for its type. */
11362 gcc_assert (cp_unevaluated_operand != 0);
11363 /* We copy T because want to tsubst the PARM_DECL only,
11364 not the following PARM_DECLs that are chained to T. */
11366 r = tsubst_decl (c, args, complain);
11367 /* Give it the template pattern as its context; its true context
11368 hasn't been instantiated yet and this is good enough for
11370 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11373 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11374 r = ARGUMENT_PACK_SELECT_ARG (r);
11383 if (DECL_TEMPLATE_PARM_P (t))
11384 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11385 /* There is no need to substitute into namespace-scope
11387 if (DECL_NAMESPACE_SCOPE_P (t))
11389 /* If ARGS is NULL, then T is known to be non-dependent. */
11390 if (args == NULL_TREE)
11391 return integral_constant_value (t);
11393 /* Unfortunately, we cannot just call lookup_name here.
11396 template <int I> int f() {
11398 struct S { void g() { E e = a; } };
11401 When we instantiate f<7>::S::g(), say, lookup_name is not
11402 clever enough to find f<7>::a. */
11404 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11405 /*entering_scope=*/0);
11407 for (v = TYPE_VALUES (enum_type);
11409 v = TREE_CHAIN (v))
11410 if (TREE_PURPOSE (v) == DECL_NAME (t))
11411 return TREE_VALUE (v);
11413 /* We didn't find the name. That should never happen; if
11414 name-lookup found it during preliminary parsing, we
11415 should find it again here during instantiation. */
11416 gcc_unreachable ();
11421 if (DECL_CONTEXT (t))
11425 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11426 /*entering_scope=*/1);
11427 if (ctx != DECL_CONTEXT (t))
11429 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11432 if (complain & tf_error)
11433 error ("using invalid field %qD", t);
11434 return error_mark_node;
11443 case FUNCTION_DECL:
11444 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11445 || local_variable_p (t))
11446 t = tsubst (t, args, complain, in_decl);
11451 /* An OVERLOAD will always be a non-dependent overload set; an
11452 overload set from function scope will just be represented with an
11453 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11454 gcc_assert (!uses_template_parms (t));
11458 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11460 case TEMPLATE_DECL:
11461 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11462 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11463 args, complain, in_decl);
11464 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11465 return tsubst (t, args, complain, in_decl);
11466 else if (DECL_CLASS_SCOPE_P (t)
11467 && uses_template_parms (DECL_CONTEXT (t)))
11469 /* Template template argument like the following example need
11472 template <template <class> class TT> struct C {};
11473 template <class T> struct D {
11474 template <class U> struct E {};
11479 We are processing the template argument `E' in #1 for
11480 the template instantiation #2. Originally, `E' is a
11481 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11482 have to substitute this with one having context `D<int>'. */
11484 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11485 return lookup_field (context, DECL_NAME(t), 0, false);
11488 /* Ordinary template template argument. */
11492 case REINTERPRET_CAST_EXPR:
11493 case CONST_CAST_EXPR:
11494 case STATIC_CAST_EXPR:
11495 case DYNAMIC_CAST_EXPR:
11498 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11499 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11502 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11508 ++cp_unevaluated_operand;
11509 ++c_inhibit_evaluation_warnings;
11510 /* We only want to compute the number of arguments. */
11511 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11512 complain, in_decl);
11513 --cp_unevaluated_operand;
11514 --c_inhibit_evaluation_warnings;
11516 if (TREE_CODE (expanded) == TREE_VEC)
11517 len = TREE_VEC_LENGTH (expanded);
11519 if (expanded == error_mark_node)
11520 return error_mark_node;
11521 else if (PACK_EXPANSION_P (expanded)
11522 || (TREE_CODE (expanded) == TREE_VEC
11524 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11526 if (TREE_CODE (expanded) == TREE_VEC)
11527 expanded = TREE_VEC_ELT (expanded, len - 1);
11529 if (TYPE_P (expanded))
11530 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11531 complain & tf_error);
11533 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11534 complain & tf_error);
11537 return build_int_cst (size_type_node, len);
11543 case TRUTH_NOT_EXPR:
11546 case UNARY_PLUS_EXPR: /* Unary + */
11548 case AT_ENCODE_EXPR:
11552 case REALPART_EXPR:
11553 case IMAGPART_EXPR:
11555 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11556 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11558 case COMPONENT_REF:
11563 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11564 name = TREE_OPERAND (t, 1);
11565 if (TREE_CODE (name) == BIT_NOT_EXPR)
11567 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11568 complain, in_decl);
11569 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11571 else if (TREE_CODE (name) == SCOPE_REF
11572 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11574 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11575 complain, in_decl);
11576 name = TREE_OPERAND (name, 1);
11577 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11578 complain, in_decl);
11579 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11580 name = build_qualified_name (/*type=*/NULL_TREE,
11582 /*template_p=*/false);
11584 else if (TREE_CODE (name) == BASELINK)
11585 name = tsubst_baselink (name,
11586 non_reference (TREE_TYPE (object)),
11590 name = tsubst_copy (name, args, complain, in_decl);
11591 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11597 case TRUNC_DIV_EXPR:
11598 case CEIL_DIV_EXPR:
11599 case FLOOR_DIV_EXPR:
11600 case ROUND_DIV_EXPR:
11601 case EXACT_DIV_EXPR:
11605 case TRUNC_MOD_EXPR:
11606 case FLOOR_MOD_EXPR:
11607 case TRUTH_ANDIF_EXPR:
11608 case TRUTH_ORIF_EXPR:
11609 case TRUTH_AND_EXPR:
11610 case TRUTH_OR_EXPR:
11623 case COMPOUND_EXPR:
11626 case PREDECREMENT_EXPR:
11627 case PREINCREMENT_EXPR:
11628 case POSTDECREMENT_EXPR:
11629 case POSTINCREMENT_EXPR:
11631 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11632 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11635 return build_qualified_name (/*type=*/NULL_TREE,
11636 tsubst_copy (TREE_OPERAND (t, 0),
11637 args, complain, in_decl),
11638 tsubst_copy (TREE_OPERAND (t, 1),
11639 args, complain, in_decl),
11640 QUALIFIED_NAME_IS_TEMPLATE (t));
11645 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11646 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11647 NULL_TREE, NULL_TREE);
11651 int n = VL_EXP_OPERAND_LENGTH (t);
11652 tree result = build_vl_exp (CALL_EXPR, n);
11654 for (i = 0; i < n; i++)
11655 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11656 complain, in_decl);
11662 case PSEUDO_DTOR_EXPR:
11665 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11666 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11667 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11668 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11675 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11676 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11677 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11678 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11685 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11686 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11687 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11688 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11692 case TEMPLATE_ID_EXPR:
11694 /* Substituted template arguments */
11695 tree fn = TREE_OPERAND (t, 0);
11696 tree targs = TREE_OPERAND (t, 1);
11698 fn = tsubst_copy (fn, args, complain, in_decl);
11700 targs = tsubst_template_args (targs, args, complain, in_decl);
11702 return lookup_template_function (fn, targs);
11707 tree purpose, value, chain;
11709 if (t == void_list_node)
11712 purpose = TREE_PURPOSE (t);
11714 purpose = tsubst_copy (purpose, args, complain, in_decl);
11715 value = TREE_VALUE (t);
11717 value = tsubst_copy (value, args, complain, in_decl);
11718 chain = TREE_CHAIN (t);
11719 if (chain && chain != void_type_node)
11720 chain = tsubst_copy (chain, args, complain, in_decl);
11721 if (purpose == TREE_PURPOSE (t)
11722 && value == TREE_VALUE (t)
11723 && chain == TREE_CHAIN (t))
11725 return tree_cons (purpose, value, chain);
11730 case ENUMERAL_TYPE:
11732 case TEMPLATE_TYPE_PARM:
11733 case TEMPLATE_TEMPLATE_PARM:
11734 case BOUND_TEMPLATE_TEMPLATE_PARM:
11735 case TEMPLATE_PARM_INDEX:
11737 case REFERENCE_TYPE:
11739 case FUNCTION_TYPE:
11742 case TYPENAME_TYPE:
11743 case UNBOUND_CLASS_TEMPLATE:
11745 case DECLTYPE_TYPE:
11747 return tsubst (t, args, complain, in_decl);
11749 case IDENTIFIER_NODE:
11750 if (IDENTIFIER_TYPENAME_P (t))
11752 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11753 return mangle_conv_op_name_for_type (new_type);
11759 /* This is handled by tsubst_copy_and_build. */
11760 gcc_unreachable ();
11763 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11765 tsubst (TREE_TYPE (t), args, complain, in_decl));
11767 case CLEANUP_POINT_EXPR:
11768 /* We shouldn't have built any of these during initial template
11769 generation. Instead, they should be built during instantiation
11770 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11771 gcc_unreachable ();
11775 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11776 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11777 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11778 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11779 mark_used (TREE_OPERAND (r, 1));
11782 case EXPR_PACK_EXPANSION:
11783 error ("invalid use of pack expansion expression");
11784 return error_mark_node;
11786 case NONTYPE_ARGUMENT_PACK:
11787 error ("use %<...%> to expand argument pack");
11788 return error_mark_node;
11795 /* Instantiate any typedefs in the type. */
11796 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11797 r = fold_convert (type, t);
11798 gcc_assert (TREE_CODE (r) == code);
11803 /* These can sometimes show up in a partial instantiation, but never
11804 involve template parms. */
11805 gcc_assert (!uses_template_parms (t));
11809 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
11810 gcc_checking_assert (false);
11815 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11818 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11821 tree new_clauses = NULL, nc, oc;
11823 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11825 nc = copy_node (oc);
11826 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11829 switch (OMP_CLAUSE_CODE (nc))
11831 case OMP_CLAUSE_LASTPRIVATE:
11832 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11834 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11835 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11836 in_decl, /*integral_constant_expression_p=*/false);
11837 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11838 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11841 case OMP_CLAUSE_PRIVATE:
11842 case OMP_CLAUSE_SHARED:
11843 case OMP_CLAUSE_FIRSTPRIVATE:
11844 case OMP_CLAUSE_REDUCTION:
11845 case OMP_CLAUSE_COPYIN:
11846 case OMP_CLAUSE_COPYPRIVATE:
11847 case OMP_CLAUSE_IF:
11848 case OMP_CLAUSE_NUM_THREADS:
11849 case OMP_CLAUSE_SCHEDULE:
11850 case OMP_CLAUSE_COLLAPSE:
11851 OMP_CLAUSE_OPERAND (nc, 0)
11852 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11853 in_decl, /*integral_constant_expression_p=*/false);
11855 case OMP_CLAUSE_NOWAIT:
11856 case OMP_CLAUSE_ORDERED:
11857 case OMP_CLAUSE_DEFAULT:
11858 case OMP_CLAUSE_UNTIED:
11861 gcc_unreachable ();
11865 return finish_omp_clauses (nreverse (new_clauses));
11868 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11871 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11874 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11876 tree purpose, value, chain;
11881 if (TREE_CODE (t) != TREE_LIST)
11882 return tsubst_copy_and_build (t, args, complain, in_decl,
11883 /*function_p=*/false,
11884 /*integral_constant_expression_p=*/false);
11886 if (t == void_list_node)
11889 purpose = TREE_PURPOSE (t);
11891 purpose = RECUR (purpose);
11892 value = TREE_VALUE (t);
11893 if (value && TREE_CODE (value) != LABEL_DECL)
11894 value = RECUR (value);
11895 chain = TREE_CHAIN (t);
11896 if (chain && chain != void_type_node)
11897 chain = RECUR (chain);
11898 return tree_cons (purpose, value, chain);
11902 /* Substitute one OMP_FOR iterator. */
11905 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11906 tree condv, tree incrv, tree *clauses,
11907 tree args, tsubst_flags_t complain, tree in_decl,
11908 bool integral_constant_expression_p)
11910 #define RECUR(NODE) \
11911 tsubst_expr ((NODE), args, complain, in_decl, \
11912 integral_constant_expression_p)
11913 tree decl, init, cond, incr, auto_node;
11915 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11916 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11917 decl = RECUR (TREE_OPERAND (init, 0));
11918 init = TREE_OPERAND (init, 1);
11919 auto_node = type_uses_auto (TREE_TYPE (decl));
11920 if (auto_node && init)
11922 tree init_expr = init;
11923 if (TREE_CODE (init_expr) == DECL_EXPR)
11924 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11925 init_expr = RECUR (init_expr);
11927 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11929 gcc_assert (!type_dependent_expression_p (decl));
11931 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11933 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11934 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11935 if (TREE_CODE (incr) == MODIFY_EXPR)
11936 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11937 RECUR (TREE_OPERAND (incr, 1)),
11940 incr = RECUR (incr);
11941 TREE_VEC_ELT (declv, i) = decl;
11942 TREE_VEC_ELT (initv, i) = init;
11943 TREE_VEC_ELT (condv, i) = cond;
11944 TREE_VEC_ELT (incrv, i) = incr;
11948 if (init && TREE_CODE (init) != DECL_EXPR)
11951 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11953 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11954 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11955 && OMP_CLAUSE_DECL (c) == decl)
11957 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11958 && OMP_CLAUSE_DECL (c) == decl)
11959 error ("iteration variable %qD should not be firstprivate", decl);
11960 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11961 && OMP_CLAUSE_DECL (c) == decl)
11962 error ("iteration variable %qD should not be reduction", decl);
11966 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11967 OMP_CLAUSE_DECL (c) = decl;
11968 c = finish_omp_clauses (c);
11971 OMP_CLAUSE_CHAIN (c) = *clauses;
11976 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11977 if (COMPARISON_CLASS_P (cond))
11978 cond = build2 (TREE_CODE (cond), boolean_type_node,
11979 RECUR (TREE_OPERAND (cond, 0)),
11980 RECUR (TREE_OPERAND (cond, 1)));
11982 cond = RECUR (cond);
11983 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11984 switch (TREE_CODE (incr))
11986 case PREINCREMENT_EXPR:
11987 case PREDECREMENT_EXPR:
11988 case POSTINCREMENT_EXPR:
11989 case POSTDECREMENT_EXPR:
11990 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11991 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11994 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11995 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11997 tree rhs = TREE_OPERAND (incr, 1);
11998 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11999 RECUR (TREE_OPERAND (incr, 0)),
12000 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12001 RECUR (TREE_OPERAND (rhs, 0)),
12002 RECUR (TREE_OPERAND (rhs, 1))));
12005 incr = RECUR (incr);
12008 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12009 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12011 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12012 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12013 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12014 TREE_TYPE (decl), lhs,
12015 RECUR (TREE_OPERAND (incr, 2))));
12017 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12018 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12019 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12021 tree rhs = TREE_OPERAND (incr, 2);
12022 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12023 RECUR (TREE_OPERAND (incr, 0)),
12024 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12025 RECUR (TREE_OPERAND (rhs, 0)),
12026 RECUR (TREE_OPERAND (rhs, 1))));
12029 incr = RECUR (incr);
12032 incr = RECUR (incr);
12036 TREE_VEC_ELT (declv, i) = decl;
12037 TREE_VEC_ELT (initv, i) = init;
12038 TREE_VEC_ELT (condv, i) = cond;
12039 TREE_VEC_ELT (incrv, i) = incr;
12043 /* Like tsubst_copy for expressions, etc. but also does semantic
12047 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12048 bool integral_constant_expression_p)
12050 #define RECUR(NODE) \
12051 tsubst_expr ((NODE), args, complain, in_decl, \
12052 integral_constant_expression_p)
12056 if (t == NULL_TREE || t == error_mark_node)
12059 if (EXPR_HAS_LOCATION (t))
12060 input_location = EXPR_LOCATION (t);
12061 if (STATEMENT_CODE_P (TREE_CODE (t)))
12062 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12064 switch (TREE_CODE (t))
12066 case STATEMENT_LIST:
12068 tree_stmt_iterator i;
12069 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12070 RECUR (tsi_stmt (i));
12074 case CTOR_INITIALIZER:
12075 finish_mem_initializers (tsubst_initializer_list
12076 (TREE_OPERAND (t, 0), args));
12080 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12084 tmp = RECUR (EXPR_STMT_EXPR (t));
12085 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12086 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12088 finish_expr_stmt (tmp);
12092 do_using_directive (USING_STMT_NAMESPACE (t));
12097 tree decl, pattern_decl;
12100 pattern_decl = decl = DECL_EXPR_DECL (t);
12101 if (TREE_CODE (decl) == LABEL_DECL)
12102 finish_label_decl (DECL_NAME (decl));
12103 else if (TREE_CODE (decl) == USING_DECL)
12105 tree scope = USING_DECL_SCOPE (decl);
12106 tree name = DECL_NAME (decl);
12109 scope = tsubst (scope, args, complain, in_decl);
12110 decl = lookup_qualified_name (scope, name,
12111 /*is_type_p=*/false,
12112 /*complain=*/false);
12113 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12114 qualified_name_lookup_error (scope, name, decl, input_location);
12116 do_local_using_decl (decl, scope, name);
12120 init = DECL_INITIAL (decl);
12121 decl = tsubst (decl, args, complain, in_decl);
12122 if (decl != error_mark_node)
12124 /* By marking the declaration as instantiated, we avoid
12125 trying to instantiate it. Since instantiate_decl can't
12126 handle local variables, and since we've already done
12127 all that needs to be done, that's the right thing to
12129 if (TREE_CODE (decl) == VAR_DECL)
12130 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12131 if (TREE_CODE (decl) == VAR_DECL
12132 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12133 /* Anonymous aggregates are a special case. */
12134 finish_anon_union (decl);
12137 int const_init = false;
12138 maybe_push_decl (decl);
12139 if (TREE_CODE (decl) == VAR_DECL
12140 && DECL_PRETTY_FUNCTION_P (decl))
12142 /* For __PRETTY_FUNCTION__ we have to adjust the
12144 const char *const name
12145 = cxx_printable_name (current_function_decl, 2);
12146 init = cp_fname_init (name, &TREE_TYPE (decl));
12150 tree t = RECUR (init);
12154 /* If we had an initializer but it
12155 instantiated to nothing,
12156 value-initialize the object. This will
12157 only occur when the initializer was a
12158 pack expansion where the parameter packs
12159 used in that expansion were of length
12161 init = build_value_init (TREE_TYPE (decl),
12163 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12164 init = get_target_expr_sfinae (init, complain);
12170 if (TREE_CODE (decl) == VAR_DECL)
12171 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12173 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12178 /* A DECL_EXPR can also be used as an expression, in the condition
12179 clause of an if/for/while construct. */
12184 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12185 RECUR (FOR_INIT_STMT (t));
12186 finish_for_init_stmt (stmt);
12187 tmp = RECUR (FOR_COND (t));
12188 finish_for_cond (tmp, stmt);
12189 tmp = RECUR (FOR_EXPR (t));
12190 finish_for_expr (tmp, stmt);
12191 RECUR (FOR_BODY (t));
12192 finish_for_stmt (stmt);
12195 case RANGE_FOR_STMT:
12198 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12199 decl = RANGE_FOR_DECL (t);
12200 decl = tsubst (decl, args, complain, in_decl);
12201 maybe_push_decl (decl);
12202 expr = RECUR (RANGE_FOR_EXPR (t));
12203 stmt = cp_convert_range_for (stmt, decl, expr);
12204 RECUR (RANGE_FOR_BODY (t));
12205 finish_for_stmt (stmt);
12210 stmt = begin_while_stmt ();
12211 tmp = RECUR (WHILE_COND (t));
12212 finish_while_stmt_cond (tmp, stmt);
12213 RECUR (WHILE_BODY (t));
12214 finish_while_stmt (stmt);
12218 stmt = begin_do_stmt ();
12219 RECUR (DO_BODY (t));
12220 finish_do_body (stmt);
12221 tmp = RECUR (DO_COND (t));
12222 finish_do_stmt (tmp, stmt);
12226 stmt = begin_if_stmt ();
12227 tmp = RECUR (IF_COND (t));
12228 finish_if_stmt_cond (tmp, stmt);
12229 RECUR (THEN_CLAUSE (t));
12230 finish_then_clause (stmt);
12232 if (ELSE_CLAUSE (t))
12234 begin_else_clause (stmt);
12235 RECUR (ELSE_CLAUSE (t));
12236 finish_else_clause (stmt);
12239 finish_if_stmt (stmt);
12243 if (BIND_EXPR_BODY_BLOCK (t))
12244 stmt = begin_function_body ();
12246 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12247 ? BCS_TRY_BLOCK : 0);
12249 RECUR (BIND_EXPR_BODY (t));
12251 if (BIND_EXPR_BODY_BLOCK (t))
12252 finish_function_body (stmt);
12254 finish_compound_stmt (stmt);
12258 finish_break_stmt ();
12261 case CONTINUE_STMT:
12262 finish_continue_stmt ();
12266 stmt = begin_switch_stmt ();
12267 tmp = RECUR (SWITCH_STMT_COND (t));
12268 finish_switch_cond (tmp, stmt);
12269 RECUR (SWITCH_STMT_BODY (t));
12270 finish_switch_stmt (stmt);
12273 case CASE_LABEL_EXPR:
12274 finish_case_label (EXPR_LOCATION (t),
12275 RECUR (CASE_LOW (t)),
12276 RECUR (CASE_HIGH (t)));
12281 tree decl = LABEL_EXPR_LABEL (t);
12284 label = finish_label_stmt (DECL_NAME (decl));
12285 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12286 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12291 tmp = GOTO_DESTINATION (t);
12292 if (TREE_CODE (tmp) != LABEL_DECL)
12293 /* Computed goto's must be tsubst'd into. On the other hand,
12294 non-computed gotos must not be; the identifier in question
12295 will have no binding. */
12298 tmp = DECL_NAME (tmp);
12299 finish_goto_stmt (tmp);
12303 tmp = finish_asm_stmt
12304 (ASM_VOLATILE_P (t),
12305 RECUR (ASM_STRING (t)),
12306 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12307 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12308 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12309 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12311 tree asm_expr = tmp;
12312 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12313 asm_expr = TREE_OPERAND (asm_expr, 0);
12314 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12321 stmt = begin_try_block ();
12322 RECUR (TRY_STMTS (t));
12323 finish_cleanup_try_block (stmt);
12324 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12328 tree compound_stmt = NULL_TREE;
12330 if (FN_TRY_BLOCK_P (t))
12331 stmt = begin_function_try_block (&compound_stmt);
12333 stmt = begin_try_block ();
12335 RECUR (TRY_STMTS (t));
12337 if (FN_TRY_BLOCK_P (t))
12338 finish_function_try_block (stmt);
12340 finish_try_block (stmt);
12342 RECUR (TRY_HANDLERS (t));
12343 if (FN_TRY_BLOCK_P (t))
12344 finish_function_handler_sequence (stmt, compound_stmt);
12346 finish_handler_sequence (stmt);
12352 tree decl = HANDLER_PARMS (t);
12356 decl = tsubst (decl, args, complain, in_decl);
12357 /* Prevent instantiate_decl from trying to instantiate
12358 this variable. We've already done all that needs to be
12360 if (decl != error_mark_node)
12361 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12363 stmt = begin_handler ();
12364 finish_handler_parms (decl, stmt);
12365 RECUR (HANDLER_BODY (t));
12366 finish_handler (stmt);
12371 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12374 case STATIC_ASSERT:
12377 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12380 /*integral_constant_expression_p=*/true);
12381 finish_static_assert (condition,
12382 STATIC_ASSERT_MESSAGE (t),
12383 STATIC_ASSERT_SOURCE_LOCATION (t),
12384 /*member_p=*/false);
12389 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12390 args, complain, in_decl);
12391 stmt = begin_omp_parallel ();
12392 RECUR (OMP_PARALLEL_BODY (t));
12393 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12394 = OMP_PARALLEL_COMBINED (t);
12398 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12399 args, complain, in_decl);
12400 stmt = begin_omp_task ();
12401 RECUR (OMP_TASK_BODY (t));
12402 finish_omp_task (tmp, stmt);
12407 tree clauses, body, pre_body;
12408 tree declv, initv, condv, incrv;
12411 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12412 args, complain, in_decl);
12413 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12414 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12415 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12416 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12418 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12419 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12420 &clauses, args, complain, in_decl,
12421 integral_constant_expression_p);
12423 stmt = begin_omp_structured_block ();
12425 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12426 if (TREE_VEC_ELT (initv, i) == NULL
12427 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12428 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12429 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12431 tree init = RECUR (TREE_VEC_ELT (initv, i));
12432 gcc_assert (init == TREE_VEC_ELT (declv, i));
12433 TREE_VEC_ELT (initv, i) = NULL_TREE;
12437 tree decl_expr = TREE_VEC_ELT (initv, i);
12438 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12439 gcc_assert (init != NULL);
12440 TREE_VEC_ELT (initv, i) = RECUR (init);
12441 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12443 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12446 pre_body = push_stmt_list ();
12447 RECUR (OMP_FOR_PRE_BODY (t));
12448 pre_body = pop_stmt_list (pre_body);
12450 body = push_stmt_list ();
12451 RECUR (OMP_FOR_BODY (t));
12452 body = pop_stmt_list (body);
12454 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12455 body, pre_body, clauses);
12457 add_stmt (finish_omp_structured_block (stmt));
12463 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12464 stmt = push_stmt_list ();
12465 RECUR (OMP_BODY (t));
12466 stmt = pop_stmt_list (stmt);
12469 OMP_BODY (t) = stmt;
12470 OMP_CLAUSES (t) = tmp;
12478 stmt = push_stmt_list ();
12479 RECUR (OMP_BODY (t));
12480 stmt = pop_stmt_list (stmt);
12483 OMP_BODY (t) = stmt;
12488 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12490 tree op1 = TREE_OPERAND (t, 1);
12491 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12492 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12493 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12497 case EXPR_PACK_EXPANSION:
12498 error ("invalid use of pack expansion expression");
12499 return error_mark_node;
12501 case NONTYPE_ARGUMENT_PACK:
12502 error ("use %<...%> to expand argument pack");
12503 return error_mark_node;
12506 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12508 return tsubst_copy_and_build (t, args, complain, in_decl,
12509 /*function_p=*/false,
12510 integral_constant_expression_p);
12517 /* T is a postfix-expression that is not being used in a function
12518 call. Return the substituted version of T. */
12521 tsubst_non_call_postfix_expression (tree t, tree args,
12522 tsubst_flags_t complain,
12525 if (TREE_CODE (t) == SCOPE_REF)
12526 t = tsubst_qualified_id (t, args, complain, in_decl,
12527 /*done=*/false, /*address_p=*/false);
12529 t = tsubst_copy_and_build (t, args, complain, in_decl,
12530 /*function_p=*/false,
12531 /*integral_constant_expression_p=*/false);
12536 /* Like tsubst but deals with expressions and performs semantic
12537 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12540 tsubst_copy_and_build (tree t,
12542 tsubst_flags_t complain,
12545 bool integral_constant_expression_p)
12547 #define RECUR(NODE) \
12548 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12549 /*function_p=*/false, \
12550 integral_constant_expression_p)
12554 if (t == NULL_TREE || t == error_mark_node)
12557 switch (TREE_CODE (t))
12561 /* Fall through. */
12562 case IDENTIFIER_NODE:
12566 bool non_integral_constant_expression_p;
12567 const char *error_msg;
12569 if (IDENTIFIER_TYPENAME_P (t))
12571 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12572 t = mangle_conv_op_name_for_type (new_type);
12575 /* Look up the name. */
12576 decl = lookup_name (t);
12578 /* By convention, expressions use ERROR_MARK_NODE to indicate
12579 failure, not NULL_TREE. */
12580 if (decl == NULL_TREE)
12581 decl = error_mark_node;
12583 decl = finish_id_expression (t, decl, NULL_TREE,
12585 integral_constant_expression_p,
12586 /*allow_non_integral_constant_expression_p=*/false,
12587 &non_integral_constant_expression_p,
12588 /*template_p=*/false,
12590 /*address_p=*/false,
12591 /*template_arg_p=*/false,
12596 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12597 decl = unqualified_name_lookup_error (decl);
12601 case TEMPLATE_ID_EXPR:
12604 tree templ = RECUR (TREE_OPERAND (t, 0));
12605 tree targs = TREE_OPERAND (t, 1);
12608 targs = tsubst_template_args (targs, args, complain, in_decl);
12610 if (TREE_CODE (templ) == COMPONENT_REF)
12612 object = TREE_OPERAND (templ, 0);
12613 templ = TREE_OPERAND (templ, 1);
12616 object = NULL_TREE;
12617 templ = lookup_template_function (templ, targs);
12620 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12621 object, templ, NULL_TREE);
12623 return baselink_for_fns (templ);
12628 tree r = RECUR (TREE_OPERAND (t, 0));
12630 if (REFERENCE_REF_P (t))
12632 /* A type conversion to reference type will be enclosed in
12633 such an indirect ref, but the substitution of the cast
12634 will have also added such an indirect ref. */
12635 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12636 r = convert_from_reference (r);
12639 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12645 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12646 RECUR (TREE_OPERAND (t, 0)));
12649 case REINTERPRET_CAST_EXPR:
12650 case CONST_CAST_EXPR:
12651 case DYNAMIC_CAST_EXPR:
12652 case STATIC_CAST_EXPR:
12657 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12658 if (integral_constant_expression_p
12659 && !cast_valid_in_integral_constant_expression_p (type))
12661 if (complain & tf_error)
12662 error ("a cast to a type other than an integral or "
12663 "enumeration type cannot appear in a constant-expression");
12664 return error_mark_node;
12667 op = RECUR (TREE_OPERAND (t, 0));
12669 switch (TREE_CODE (t))
12672 return build_functional_cast (type, op, complain);
12673 case REINTERPRET_CAST_EXPR:
12674 return build_reinterpret_cast (type, op, complain);
12675 case CONST_CAST_EXPR:
12676 return build_const_cast (type, op, complain);
12677 case DYNAMIC_CAST_EXPR:
12678 return build_dynamic_cast (type, op, complain);
12679 case STATIC_CAST_EXPR:
12680 return build_static_cast (type, op, complain);
12682 gcc_unreachable ();
12686 case POSTDECREMENT_EXPR:
12687 case POSTINCREMENT_EXPR:
12688 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12689 args, complain, in_decl);
12690 return build_x_unary_op (TREE_CODE (t), op1, complain);
12692 case PREDECREMENT_EXPR:
12693 case PREINCREMENT_EXPR:
12697 case TRUTH_NOT_EXPR:
12698 case UNARY_PLUS_EXPR: /* Unary + */
12699 case REALPART_EXPR:
12700 case IMAGPART_EXPR:
12701 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12705 op1 = TREE_OPERAND (t, 0);
12706 if (TREE_CODE (op1) == LABEL_DECL)
12707 return finish_label_address_expr (DECL_NAME (op1),
12708 EXPR_LOCATION (op1));
12709 if (TREE_CODE (op1) == SCOPE_REF)
12710 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12711 /*done=*/true, /*address_p=*/true);
12713 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12715 return build_x_unary_op (ADDR_EXPR, op1, complain);
12720 case TRUNC_DIV_EXPR:
12721 case CEIL_DIV_EXPR:
12722 case FLOOR_DIV_EXPR:
12723 case ROUND_DIV_EXPR:
12724 case EXACT_DIV_EXPR:
12728 case TRUNC_MOD_EXPR:
12729 case FLOOR_MOD_EXPR:
12730 case TRUTH_ANDIF_EXPR:
12731 case TRUTH_ORIF_EXPR:
12732 case TRUTH_AND_EXPR:
12733 case TRUTH_OR_EXPR:
12748 return build_x_binary_op
12750 RECUR (TREE_OPERAND (t, 0)),
12751 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12753 : TREE_CODE (TREE_OPERAND (t, 0))),
12754 RECUR (TREE_OPERAND (t, 1)),
12755 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12757 : TREE_CODE (TREE_OPERAND (t, 1))),
12762 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12763 /*address_p=*/false);
12765 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12766 args, complain, in_decl);
12767 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12770 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12771 return tsubst_copy (t, args, complain, in_decl);
12775 op1 = TREE_OPERAND (t, 0);
12778 /* When there are no ARGS, we are trying to evaluate a
12779 non-dependent expression from the parser. Trying to do
12780 the substitutions may not work. */
12782 op1 = TREE_TYPE (op1);
12786 ++cp_unevaluated_operand;
12787 ++c_inhibit_evaluation_warnings;
12788 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12789 /*function_p=*/false,
12790 /*integral_constant_expression_p=*/false);
12791 --cp_unevaluated_operand;
12792 --c_inhibit_evaluation_warnings;
12795 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12796 complain & tf_error);
12798 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12799 complain & tf_error);
12801 case AT_ENCODE_EXPR:
12803 op1 = TREE_OPERAND (t, 0);
12804 ++cp_unevaluated_operand;
12805 ++c_inhibit_evaluation_warnings;
12806 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12807 /*function_p=*/false,
12808 /*integral_constant_expression_p=*/false);
12809 --cp_unevaluated_operand;
12810 --c_inhibit_evaluation_warnings;
12811 return objc_build_encode_expr (op1);
12814 case NOEXCEPT_EXPR:
12815 op1 = TREE_OPERAND (t, 0);
12816 ++cp_unevaluated_operand;
12817 ++c_inhibit_evaluation_warnings;
12818 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12819 /*function_p=*/false,
12820 /*integral_constant_expression_p=*/false);
12821 --cp_unevaluated_operand;
12822 --c_inhibit_evaluation_warnings;
12823 return finish_noexcept_expr (op1, complain);
12827 tree r = build_x_modify_expr
12828 (RECUR (TREE_OPERAND (t, 0)),
12829 TREE_CODE (TREE_OPERAND (t, 1)),
12830 RECUR (TREE_OPERAND (t, 2)),
12832 /* TREE_NO_WARNING must be set if either the expression was
12833 parenthesized or it uses an operator such as >>= rather
12834 than plain assignment. In the former case, it was already
12835 set and must be copied. In the latter case,
12836 build_x_modify_expr sets it and it must not be reset
12838 if (TREE_NO_WARNING (t))
12839 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12844 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12845 args, complain, in_decl);
12846 /* Remember that there was a reference to this entity. */
12849 return build_x_arrow (op1);
12853 tree placement = RECUR (TREE_OPERAND (t, 0));
12854 tree init = RECUR (TREE_OPERAND (t, 3));
12855 VEC(tree,gc) *placement_vec;
12856 VEC(tree,gc) *init_vec;
12859 if (placement == NULL_TREE)
12860 placement_vec = NULL;
12863 placement_vec = make_tree_vector ();
12864 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12865 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12868 /* If there was an initializer in the original tree, but it
12869 instantiated to an empty list, then we should pass a
12870 non-NULL empty vector to tell build_new that it was an
12871 empty initializer() rather than no initializer. This can
12872 only happen when the initializer is a pack expansion whose
12873 parameter packs are of length zero. */
12874 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12878 init_vec = make_tree_vector ();
12879 if (init == void_zero_node)
12880 gcc_assert (init_vec != NULL);
12883 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12884 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12888 ret = build_new (&placement_vec,
12889 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
12890 RECUR (TREE_OPERAND (t, 2)),
12892 NEW_EXPR_USE_GLOBAL (t),
12895 if (placement_vec != NULL)
12896 release_tree_vector (placement_vec);
12897 if (init_vec != NULL)
12898 release_tree_vector (init_vec);
12904 return delete_sanity
12905 (RECUR (TREE_OPERAND (t, 0)),
12906 RECUR (TREE_OPERAND (t, 1)),
12907 DELETE_EXPR_USE_VEC (t),
12908 DELETE_EXPR_USE_GLOBAL (t),
12911 case COMPOUND_EXPR:
12912 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12913 RECUR (TREE_OPERAND (t, 1)),
12919 VEC(tree,gc) *call_args;
12920 unsigned int nargs, i;
12925 function = CALL_EXPR_FN (t);
12926 /* When we parsed the expression, we determined whether or
12927 not Koenig lookup should be performed. */
12928 koenig_p = KOENIG_LOOKUP_P (t);
12929 if (TREE_CODE (function) == SCOPE_REF)
12931 qualified_p = true;
12932 function = tsubst_qualified_id (function, args, complain, in_decl,
12934 /*address_p=*/false);
12936 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
12938 /* Do nothing; calling tsubst_copy_and_build on an identifier
12939 would incorrectly perform unqualified lookup again.
12941 Note that we can also have an IDENTIFIER_NODE if the earlier
12942 unqualified lookup found a member function; in that case
12943 koenig_p will be false and we do want to do the lookup
12944 again to find the instantiated member function.
12946 FIXME but doing that causes c++/15272, so we need to stop
12947 using IDENTIFIER_NODE in that situation. */
12948 qualified_p = false;
12952 if (TREE_CODE (function) == COMPONENT_REF)
12954 tree op = TREE_OPERAND (function, 1);
12956 qualified_p = (TREE_CODE (op) == SCOPE_REF
12957 || (BASELINK_P (op)
12958 && BASELINK_QUALIFIED_P (op)));
12961 qualified_p = false;
12963 function = tsubst_copy_and_build (function, args, complain,
12966 integral_constant_expression_p);
12968 if (BASELINK_P (function))
12969 qualified_p = true;
12972 nargs = call_expr_nargs (t);
12973 call_args = make_tree_vector ();
12974 for (i = 0; i < nargs; ++i)
12976 tree arg = CALL_EXPR_ARG (t, i);
12978 if (!PACK_EXPANSION_P (arg))
12979 VEC_safe_push (tree, gc, call_args,
12980 RECUR (CALL_EXPR_ARG (t, i)));
12983 /* Expand the pack expansion and push each entry onto
12985 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12986 if (TREE_CODE (arg) == TREE_VEC)
12988 unsigned int len, j;
12990 len = TREE_VEC_LENGTH (arg);
12991 for (j = 0; j < len; ++j)
12993 tree value = TREE_VEC_ELT (arg, j);
12994 if (value != NULL_TREE)
12995 value = convert_from_reference (value);
12996 VEC_safe_push (tree, gc, call_args, value);
13001 /* A partial substitution. Add one entry. */
13002 VEC_safe_push (tree, gc, call_args, arg);
13007 /* We do not perform argument-dependent lookup if normal
13008 lookup finds a non-function, in accordance with the
13009 expected resolution of DR 218. */
13011 && ((is_overloaded_fn (function)
13012 /* If lookup found a member function, the Koenig lookup is
13013 not appropriate, even if an unqualified-name was used
13014 to denote the function. */
13015 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13016 || TREE_CODE (function) == IDENTIFIER_NODE)
13017 /* Only do this when substitution turns a dependent call
13018 into a non-dependent call. */
13019 && type_dependent_expression_p_push (t)
13020 && !any_type_dependent_arguments_p (call_args))
13021 function = perform_koenig_lookup (function, call_args, false,
13024 if (TREE_CODE (function) == IDENTIFIER_NODE
13025 && !any_type_dependent_arguments_p (call_args))
13027 if (koenig_p && (complain & tf_warning_or_error))
13029 /* For backwards compatibility and good diagnostics, try
13030 the unqualified lookup again if we aren't in SFINAE
13032 tree unq = (tsubst_copy_and_build
13033 (function, args, complain, in_decl, true,
13034 integral_constant_expression_p));
13035 if (unq != function)
13038 if (TREE_CODE (fn) == COMPONENT_REF)
13039 fn = TREE_OPERAND (fn, 1);
13040 if (is_overloaded_fn (fn))
13041 fn = get_first_fn (fn);
13042 permerror (EXPR_LOC_OR_HERE (t),
13043 "%qD was not declared in this scope, "
13044 "and no declarations were found by "
13045 "argument-dependent lookup at the point "
13046 "of instantiation", function);
13047 if (DECL_CLASS_SCOPE_P (fn))
13049 inform (EXPR_LOC_OR_HERE (t),
13050 "declarations in dependent base %qT are "
13051 "not found by unqualified lookup",
13052 DECL_CLASS_CONTEXT (fn));
13053 if (current_class_ptr)
13054 inform (EXPR_LOC_OR_HERE (t),
13055 "use %<this->%D%> instead", function);
13057 inform (EXPR_LOC_OR_HERE (t),
13058 "use %<%T::%D%> instead",
13059 current_class_name, function);
13062 inform (0, "%q+D declared here, later in the "
13063 "translation unit", fn);
13067 if (TREE_CODE (function) == IDENTIFIER_NODE)
13069 unqualified_name_lookup_error (function);
13070 release_tree_vector (call_args);
13071 return error_mark_node;
13075 /* Remember that there was a reference to this entity. */
13076 if (DECL_P (function))
13077 mark_used (function);
13079 if (TREE_CODE (function) == OFFSET_REF)
13080 ret = build_offset_ref_call_from_tree (function, &call_args);
13081 else if (TREE_CODE (function) == COMPONENT_REF)
13083 tree instance = TREE_OPERAND (function, 0);
13084 tree fn = TREE_OPERAND (function, 1);
13086 if (processing_template_decl
13087 && (type_dependent_expression_p (instance)
13088 || (!BASELINK_P (fn)
13089 && TREE_CODE (fn) != FIELD_DECL)
13090 || type_dependent_expression_p (fn)
13091 || any_type_dependent_arguments_p (call_args)))
13092 ret = build_nt_call_vec (function, call_args);
13093 else if (!BASELINK_P (fn))
13094 ret = finish_call_expr (function, &call_args,
13095 /*disallow_virtual=*/false,
13096 /*koenig_p=*/false,
13099 ret = (build_new_method_call
13101 &call_args, NULL_TREE,
13102 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13107 ret = finish_call_expr (function, &call_args,
13108 /*disallow_virtual=*/qualified_p,
13112 release_tree_vector (call_args);
13118 return build_x_conditional_expr
13119 (RECUR (TREE_OPERAND (t, 0)),
13120 RECUR (TREE_OPERAND (t, 1)),
13121 RECUR (TREE_OPERAND (t, 2)),
13124 case PSEUDO_DTOR_EXPR:
13125 return finish_pseudo_destructor_expr
13126 (RECUR (TREE_OPERAND (t, 0)),
13127 RECUR (TREE_OPERAND (t, 1)),
13128 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13132 tree purpose, value, chain;
13134 if (t == void_list_node)
13137 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13138 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13140 /* We have pack expansions, so expand those and
13141 create a new list out of it. */
13142 tree purposevec = NULL_TREE;
13143 tree valuevec = NULL_TREE;
13147 /* Expand the argument expressions. */
13148 if (TREE_PURPOSE (t))
13149 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13150 complain, in_decl);
13151 if (TREE_VALUE (t))
13152 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13153 complain, in_decl);
13155 /* Build the rest of the list. */
13156 chain = TREE_CHAIN (t);
13157 if (chain && chain != void_type_node)
13158 chain = RECUR (chain);
13160 /* Determine the number of arguments. */
13161 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13163 len = TREE_VEC_LENGTH (purposevec);
13164 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13166 else if (TREE_CODE (valuevec) == TREE_VEC)
13167 len = TREE_VEC_LENGTH (valuevec);
13170 /* Since we only performed a partial substitution into
13171 the argument pack, we only return a single list
13173 if (purposevec == TREE_PURPOSE (t)
13174 && valuevec == TREE_VALUE (t)
13175 && chain == TREE_CHAIN (t))
13178 return tree_cons (purposevec, valuevec, chain);
13181 /* Convert the argument vectors into a TREE_LIST */
13185 /* Grab the Ith values. */
13187 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13190 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13193 /* Build the list (backwards). */
13194 chain = tree_cons (purpose, value, chain);
13200 purpose = TREE_PURPOSE (t);
13202 purpose = RECUR (purpose);
13203 value = TREE_VALUE (t);
13205 value = RECUR (value);
13206 chain = TREE_CHAIN (t);
13207 if (chain && chain != void_type_node)
13208 chain = RECUR (chain);
13209 if (purpose == TREE_PURPOSE (t)
13210 && value == TREE_VALUE (t)
13211 && chain == TREE_CHAIN (t))
13213 return tree_cons (purpose, value, chain);
13216 case COMPONENT_REF:
13222 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13223 args, complain, in_decl);
13224 /* Remember that there was a reference to this entity. */
13225 if (DECL_P (object))
13226 mark_used (object);
13227 object_type = TREE_TYPE (object);
13229 member = TREE_OPERAND (t, 1);
13230 if (BASELINK_P (member))
13231 member = tsubst_baselink (member,
13232 non_reference (TREE_TYPE (object)),
13233 args, complain, in_decl);
13235 member = tsubst_copy (member, args, complain, in_decl);
13236 if (member == error_mark_node)
13237 return error_mark_node;
13239 if (object_type && !CLASS_TYPE_P (object_type))
13241 if (SCALAR_TYPE_P (object_type))
13243 tree s = NULL_TREE;
13244 tree dtor = member;
13246 if (TREE_CODE (dtor) == SCOPE_REF)
13248 s = TREE_OPERAND (dtor, 0);
13249 dtor = TREE_OPERAND (dtor, 1);
13251 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13253 dtor = TREE_OPERAND (dtor, 0);
13255 return finish_pseudo_destructor_expr (object, s, dtor);
13259 else if (TREE_CODE (member) == SCOPE_REF
13260 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13265 /* Lookup the template functions now that we know what the
13267 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13268 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13269 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13270 /*is_type_p=*/false,
13271 /*complain=*/false);
13272 if (BASELINK_P (member))
13274 BASELINK_FUNCTIONS (member)
13275 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13277 member = (adjust_result_of_qualified_name_lookup
13278 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13283 qualified_name_lookup_error (object_type, tmpl, member,
13285 return error_mark_node;
13288 else if (TREE_CODE (member) == SCOPE_REF
13289 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13290 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13292 if (complain & tf_error)
13294 if (TYPE_P (TREE_OPERAND (member, 0)))
13295 error ("%qT is not a class or namespace",
13296 TREE_OPERAND (member, 0));
13298 error ("%qD is not a class or namespace",
13299 TREE_OPERAND (member, 0));
13301 return error_mark_node;
13303 else if (TREE_CODE (member) == FIELD_DECL)
13304 return finish_non_static_data_member (member, object, NULL_TREE);
13306 return finish_class_member_access_expr (object, member,
13307 /*template_p=*/false,
13313 (RECUR (TREE_OPERAND (t, 0)));
13317 VEC(constructor_elt,gc) *n;
13318 constructor_elt *ce;
13319 unsigned HOST_WIDE_INT idx;
13320 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13321 bool process_index_p;
13323 bool need_copy_p = false;
13326 if (type == error_mark_node)
13327 return error_mark_node;
13329 /* digest_init will do the wrong thing if we let it. */
13330 if (type && TYPE_PTRMEMFUNC_P (type))
13333 /* We do not want to process the index of aggregate
13334 initializers as they are identifier nodes which will be
13335 looked up by digest_init. */
13336 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13338 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13339 newlen = VEC_length (constructor_elt, n);
13340 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13342 if (ce->index && process_index_p)
13343 ce->index = RECUR (ce->index);
13345 if (PACK_EXPANSION_P (ce->value))
13347 /* Substitute into the pack expansion. */
13348 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13351 if (ce->value == error_mark_node
13352 || PACK_EXPANSION_P (ce->value))
13354 else if (TREE_VEC_LENGTH (ce->value) == 1)
13355 /* Just move the argument into place. */
13356 ce->value = TREE_VEC_ELT (ce->value, 0);
13359 /* Update the length of the final CONSTRUCTOR
13360 arguments vector, and note that we will need to
13362 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13363 need_copy_p = true;
13367 ce->value = RECUR (ce->value);
13372 VEC(constructor_elt,gc) *old_n = n;
13374 n = VEC_alloc (constructor_elt, gc, newlen);
13375 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13377 if (TREE_CODE (ce->value) == TREE_VEC)
13379 int i, len = TREE_VEC_LENGTH (ce->value);
13380 for (i = 0; i < len; ++i)
13381 CONSTRUCTOR_APPEND_ELT (n, 0,
13382 TREE_VEC_ELT (ce->value, i));
13385 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13389 r = build_constructor (init_list_type_node, n);
13390 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13392 if (TREE_HAS_CONSTRUCTOR (t))
13393 return finish_compound_literal (type, r, complain);
13395 TREE_TYPE (r) = type;
13401 tree operand_0 = TREE_OPERAND (t, 0);
13402 if (TYPE_P (operand_0))
13404 operand_0 = tsubst (operand_0, args, complain, in_decl);
13405 return get_typeid (operand_0);
13409 operand_0 = RECUR (operand_0);
13410 return build_typeid (operand_0);
13421 tree r = tsubst_copy (t, args, complain, in_decl);
13423 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13424 /* If the original type was a reference, we'll be wrapped in
13425 the appropriate INDIRECT_REF. */
13426 r = convert_from_reference (r);
13431 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13432 tsubst (TREE_TYPE (t), args, complain, in_decl));
13434 case OFFSETOF_EXPR:
13435 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13439 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13440 complain, in_decl);
13442 tree type2 = TRAIT_EXPR_TYPE2 (t);
13444 type2 = tsubst_copy (type2, args, complain, in_decl);
13446 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13451 tree old_stmt_expr = cur_stmt_expr;
13452 tree stmt_expr = begin_stmt_expr ();
13454 cur_stmt_expr = stmt_expr;
13455 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13456 integral_constant_expression_p);
13457 stmt_expr = finish_stmt_expr (stmt_expr, false);
13458 cur_stmt_expr = old_stmt_expr;
13460 /* If the resulting list of expression statement is empty,
13461 fold it further into void_zero_node. */
13462 if (empty_expr_stmt_p (stmt_expr))
13463 stmt_expr = void_zero_node;
13469 t = tsubst_copy (t, args, complain, in_decl);
13470 /* As in finish_id_expression, we resolve enumeration constants
13471 to their underlying values. */
13472 if (TREE_CODE (t) == CONST_DECL)
13474 used_types_insert (TREE_TYPE (t));
13475 return DECL_INITIAL (t);
13481 tree r = build_lambda_expr ();
13483 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13484 TREE_TYPE (r) = type;
13485 CLASSTYPE_LAMBDA_EXPR (type) = r;
13487 LAMBDA_EXPR_LOCATION (r)
13488 = LAMBDA_EXPR_LOCATION (t);
13489 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13490 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13491 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13492 LAMBDA_EXPR_DISCRIMINATOR (r)
13493 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13494 LAMBDA_EXPR_CAPTURE_LIST (r)
13495 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13496 LAMBDA_EXPR_THIS_CAPTURE (r)
13497 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
13498 LAMBDA_EXPR_EXTRA_SCOPE (r)
13499 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13501 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13502 determine_visibility (TYPE_NAME (type));
13503 /* Now that we know visibility, instantiate the type so we have a
13504 declaration of the op() for later calls to lambda_function. */
13505 complete_type (type);
13507 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13509 apply_lambda_return_type (r, type);
13511 return build_lambda_object (r);
13515 /* We can get here for a constant initializer of non-dependent type.
13516 FIXME stop folding in cp_parser_initializer_clause. */
13517 gcc_assert (TREE_CONSTANT (t));
13519 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
13520 TREE_CONSTANT (r) = true;
13525 /* Handle Objective-C++ constructs, if appropriate. */
13528 = objcp_tsubst_copy_and_build (t, args, complain,
13529 in_decl, /*function_p=*/false);
13533 return tsubst_copy (t, args, complain, in_decl);
13539 /* Verify that the instantiated ARGS are valid. For type arguments,
13540 make sure that the type's linkage is ok. For non-type arguments,
13541 make sure they are constants if they are integral or enumerations.
13542 Emit an error under control of COMPLAIN, and return TRUE on error. */
13545 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13547 if (ARGUMENT_PACK_P (t))
13549 tree vec = ARGUMENT_PACK_ARGS (t);
13550 int len = TREE_VEC_LENGTH (vec);
13551 bool result = false;
13554 for (i = 0; i < len; ++i)
13555 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13559 else if (TYPE_P (t))
13561 /* [basic.link]: A name with no linkage (notably, the name
13562 of a class or enumeration declared in a local scope)
13563 shall not be used to declare an entity with linkage.
13564 This implies that names with no linkage cannot be used as
13567 DR 757 relaxes this restriction for C++0x. */
13568 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13569 : no_linkage_check (t, /*relaxed_p=*/false));
13573 /* DR 488 makes use of a type with no linkage cause
13574 type deduction to fail. */
13575 if (complain & tf_error)
13577 if (TYPE_ANONYMOUS_P (nt))
13578 error ("%qT is/uses anonymous type", t);
13580 error ("template argument for %qD uses local type %qT",
13585 /* In order to avoid all sorts of complications, we do not
13586 allow variably-modified types as template arguments. */
13587 else if (variably_modified_type_p (t, NULL_TREE))
13589 if (complain & tf_error)
13590 error ("%qT is a variably modified type", t);
13594 /* A non-type argument of integral or enumerated type must be a
13596 else if (TREE_TYPE (t)
13597 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13598 && !TREE_CONSTANT (t))
13600 if (complain & tf_error)
13601 error ("integral expression %qE is not constant", t);
13608 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13610 int ix, len = DECL_NTPARMS (tmpl);
13611 bool result = false;
13613 for (ix = 0; ix != len; ix++)
13615 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13618 if (result && (complain & tf_error))
13619 error (" trying to instantiate %qD", tmpl);
13623 /* In C++0x, it's possible to have a function template whose type depends
13624 on itself recursively. This is most obvious with decltype, but can also
13625 occur with enumeration scope (c++/48969). So we need to catch infinite
13626 recursion and reject the substitution at deduction time; this function
13627 will return error_mark_node for any repeated substitution.
13629 This also catches excessive recursion such as when f<N> depends on
13630 f<N-1> across all integers, and returns error_mark_node for all the
13631 substitutions back up to the initial one.
13633 This is, of course, not reentrant. */
13636 deduction_tsubst_fntype (tree fn, tree targs)
13638 static bool excessive_deduction_depth;
13639 static int deduction_depth;
13640 struct pending_template *old_last_pend = last_pending_template;
13642 tree fntype = TREE_TYPE (fn);
13646 if (excessive_deduction_depth)
13647 return error_mark_node;
13649 tinst = build_tree_list (fn, targs);
13650 if (!push_tinst_level (tinst))
13652 excessive_deduction_depth = true;
13654 return error_mark_node;
13657 input_location = DECL_SOURCE_LOCATION (fn);
13659 push_deduction_access_scope (fn);
13660 r = tsubst (fntype, targs, tf_none, NULL_TREE);
13661 pop_deduction_access_scope (fn);
13664 if (excessive_deduction_depth)
13666 r = error_mark_node;
13667 if (deduction_depth == 0)
13668 /* Reset once we're all the way out. */
13669 excessive_deduction_depth = false;
13672 pop_tinst_level ();
13673 /* We can't free this if a pending_template entry is pointing at it. */
13674 if (last_pending_template == old_last_pend)
13679 /* Instantiate the indicated variable or function template TMPL with
13680 the template arguments in TARG_PTR. */
13683 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
13685 tree targ_ptr = orig_args;
13689 HOST_WIDE_INT saved_processing_template_decl;
13691 if (tmpl == error_mark_node)
13692 return error_mark_node;
13694 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13696 /* If this function is a clone, handle it specially. */
13697 if (DECL_CLONED_FUNCTION_P (tmpl))
13702 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13703 DECL_CLONED_FUNCTION. */
13704 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13705 targ_ptr, complain);
13706 if (spec == error_mark_node)
13707 return error_mark_node;
13709 /* Look for the clone. */
13710 FOR_EACH_CLONE (clone, spec)
13711 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13713 /* We should always have found the clone by now. */
13714 gcc_unreachable ();
13718 /* Check to see if we already have this specialization. */
13719 gen_tmpl = most_general_template (tmpl);
13720 if (tmpl != gen_tmpl)
13721 /* The TMPL is a partial instantiation. To get a full set of
13722 arguments we must add the arguments used to perform the
13723 partial instantiation. */
13724 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13727 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13728 but it doesn't seem to be on the hot path. */
13729 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13731 gcc_assert (tmpl == gen_tmpl
13732 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13734 || fndecl == NULL_TREE);
13736 if (spec != NULL_TREE)
13739 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13741 return error_mark_node;
13743 /* We are building a FUNCTION_DECL, during which the access of its
13744 parameters and return types have to be checked. However this
13745 FUNCTION_DECL which is the desired context for access checking
13746 is not built yet. We solve this chicken-and-egg problem by
13747 deferring all checks until we have the FUNCTION_DECL. */
13748 push_deferring_access_checks (dk_deferred);
13750 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13751 (because, for example, we have encountered a non-dependent
13752 function call in the body of a template function and must now
13753 determine which of several overloaded functions will be called),
13754 within the instantiation itself we are not processing a
13756 saved_processing_template_decl = processing_template_decl;
13757 processing_template_decl = 0;
13758 /* Substitute template parameters to obtain the specialization. */
13759 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13760 targ_ptr, complain, gen_tmpl);
13761 processing_template_decl = saved_processing_template_decl;
13762 if (fndecl == error_mark_node)
13763 return error_mark_node;
13765 /* Now we know the specialization, compute access previously
13767 push_access_scope (fndecl);
13769 /* Some typedefs referenced from within the template code need to be access
13770 checked at template instantiation time, i.e now. These types were
13771 added to the template at parsing time. Let's get those and perfom
13772 the acces checks then. */
13773 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13774 perform_deferred_access_checks ();
13775 pop_access_scope (fndecl);
13776 pop_deferring_access_checks ();
13778 /* The DECL_TI_TEMPLATE should always be the immediate parent
13779 template, not the most general template. */
13780 DECL_TI_TEMPLATE (fndecl) = tmpl;
13782 /* If we've just instantiated the main entry point for a function,
13783 instantiate all the alternate entry points as well. We do this
13784 by cloning the instantiation of the main entry point, not by
13785 instantiating the template clones. */
13786 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13787 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13792 /* Wrapper for instantiate_template_1. */
13795 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13798 timevar_push (TV_TEMPLATE_INST);
13799 ret = instantiate_template_1 (tmpl, orig_args, complain);
13800 timevar_pop (TV_TEMPLATE_INST);
13804 /* We're going to do deduction substitution on the type of TMPL, a function
13805 template. In C++11 mode, push into that access scope. In C++03 mode,
13806 disable access checking. */
13809 push_deduction_access_scope (tree tmpl)
13811 if (cxx_dialect >= cxx0x)
13812 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13814 push_deferring_access_checks (dk_no_check);
13817 /* And pop back out. */
13820 pop_deduction_access_scope (tree tmpl)
13822 if (cxx_dialect >= cxx0x)
13823 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
13825 pop_deferring_access_checks ();
13828 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13829 NARGS elements of the arguments that are being used when calling
13830 it. TARGS is a vector into which the deduced template arguments
13833 Return zero for success, 2 for an incomplete match that doesn't resolve
13834 all the types, and 1 for complete failure. An error message will be
13835 printed only for an incomplete match.
13837 If FN is a conversion operator, or we are trying to produce a specific
13838 specialization, RETURN_TYPE is the return type desired.
13840 The EXPLICIT_TARGS are explicit template arguments provided via a
13843 The parameter STRICT is one of:
13846 We are deducing arguments for a function call, as in
13847 [temp.deduct.call].
13850 We are deducing arguments for a conversion function, as in
13851 [temp.deduct.conv].
13854 We are deducing arguments when doing an explicit instantiation
13855 as in [temp.explicit], when determining an explicit specialization
13856 as in [temp.expl.spec], or when taking the address of a function
13857 template, as in [temp.deduct.funcaddr]. */
13860 fn_type_unification (tree fn,
13861 tree explicit_targs,
13864 unsigned int nargs,
13866 unification_kind_t strict,
13872 bool incomplete_argument_packs_p = false;
13874 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13876 fntype = TREE_TYPE (fn);
13877 if (explicit_targs)
13881 The specified template arguments must match the template
13882 parameters in kind (i.e., type, nontype, template), and there
13883 must not be more arguments than there are parameters;
13884 otherwise type deduction fails.
13886 Nontype arguments must match the types of the corresponding
13887 nontype template parameters, or must be convertible to the
13888 types of the corresponding nontype parameters as specified in
13889 _temp.arg.nontype_, otherwise type deduction fails.
13891 All references in the function type of the function template
13892 to the corresponding template parameters are replaced by the
13893 specified template argument values. If a substitution in a
13894 template parameter or in the function type of the function
13895 template results in an invalid type, type deduction fails. */
13896 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13897 int i, len = TREE_VEC_LENGTH (tparms);
13898 tree converted_args;
13899 bool incomplete = false;
13901 if (explicit_targs == error_mark_node)
13905 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13906 /*require_all_args=*/false,
13907 /*use_default_args=*/false));
13908 if (converted_args == error_mark_node)
13911 /* Substitute the explicit args into the function type. This is
13912 necessary so that, for instance, explicitly declared function
13913 arguments can match null pointed constants. If we were given
13914 an incomplete set of explicit args, we must not do semantic
13915 processing during substitution as we could create partial
13917 for (i = 0; i < len; i++)
13919 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13920 bool parameter_pack = false;
13922 /* Dig out the actual parm. */
13923 if (TREE_CODE (parm) == TYPE_DECL
13924 || TREE_CODE (parm) == TEMPLATE_DECL)
13926 parm = TREE_TYPE (parm);
13927 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13929 else if (TREE_CODE (parm) == PARM_DECL)
13931 parm = DECL_INITIAL (parm);
13932 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13935 if (parameter_pack)
13939 template_parm_level_and_index (parm, &level, &idx);
13941 /* Mark the argument pack as "incomplete". We could
13942 still deduce more arguments during unification.
13943 We remove this mark in type_unification_real. */
13944 targ = TMPL_ARG (converted_args, level, idx);
13947 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13948 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13949 = ARGUMENT_PACK_ARGS (targ);
13952 /* We have some incomplete argument packs. */
13953 incomplete_argument_packs_p = true;
13957 if (incomplete_argument_packs_p)
13958 /* Any substitution is guaranteed to be incomplete if there
13959 are incomplete argument packs, because we can still deduce
13963 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13965 processing_template_decl += incomplete;
13966 fntype = deduction_tsubst_fntype (fn, converted_args);
13967 processing_template_decl -= incomplete;
13969 if (fntype == error_mark_node)
13972 /* Place the explicitly specified arguments in TARGS. */
13973 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13974 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13977 /* Never do unification on the 'this' parameter. */
13978 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13984 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13985 new_args = XALLOCAVEC (tree, nargs + 1);
13986 new_args[0] = return_type;
13987 memcpy (new_args + 1, args, nargs * sizeof (tree));
13992 /* We allow incomplete unification without an error message here
13993 because the standard doesn't seem to explicitly prohibit it. Our
13994 callers must be ready to deal with unification failures in any
13996 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13997 targs, parms, args, nargs, /*subr=*/0,
14000 /* Now that we have bindings for all of the template arguments,
14001 ensure that the arguments deduced for the template template
14002 parameters have compatible template parameter lists. We cannot
14003 check this property before we have deduced all template
14004 arguments, because the template parameter types of a template
14005 template parameter might depend on prior template parameters
14006 deduced after the template template parameter. The following
14007 ill-formed example illustrates this issue:
14009 template<typename T, template<T> class C> void f(C<5>, T);
14011 template<int N> struct X {};
14014 f(X<5>(), 5l); // error: template argument deduction fails
14017 The template parameter list of 'C' depends on the template type
14018 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14019 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14020 time that we deduce 'C'. */
14022 && !template_template_parm_bindings_ok_p
14023 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14027 /* All is well so far. Now, check:
14031 When all template arguments have been deduced, all uses of
14032 template parameters in nondeduced contexts are replaced with
14033 the corresponding deduced argument values. If the
14034 substitution results in an invalid type, as described above,
14035 type deduction fails. */
14037 tree substed = deduction_tsubst_fntype (fn, targs);
14038 if (substed == error_mark_node)
14041 /* If we're looking for an exact match, check that what we got
14042 is indeed an exact match. It might not be if some template
14043 parameters are used in non-deduced contexts. */
14044 if (strict == DEDUCE_EXACT)
14049 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14051 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14052 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14053 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14061 /* Adjust types before performing type deduction, as described in
14062 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14063 sections are symmetric. PARM is the type of a function parameter
14064 or the return type of the conversion function. ARG is the type of
14065 the argument passed to the call, or the type of the value
14066 initialized with the result of the conversion function.
14067 ARG_EXPR is the original argument expression, which may be null. */
14070 maybe_adjust_types_for_deduction (unification_kind_t strict,
14084 /* Swap PARM and ARG throughout the remainder of this
14085 function; the handling is precisely symmetric since PARM
14086 will initialize ARG rather than vice versa. */
14094 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14095 too, but here handle it by stripping the reference from PARM
14096 rather than by adding it to ARG. */
14097 if (TREE_CODE (*parm) == REFERENCE_TYPE
14098 && TYPE_REF_IS_RVALUE (*parm)
14099 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14100 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14101 && TREE_CODE (*arg) == REFERENCE_TYPE
14102 && !TYPE_REF_IS_RVALUE (*arg))
14103 *parm = TREE_TYPE (*parm);
14104 /* Nothing else to do in this case. */
14108 gcc_unreachable ();
14111 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14113 /* [temp.deduct.call]
14115 If P is not a reference type:
14117 --If A is an array type, the pointer type produced by the
14118 array-to-pointer standard conversion (_conv.array_) is
14119 used in place of A for type deduction; otherwise,
14121 --If A is a function type, the pointer type produced by
14122 the function-to-pointer standard conversion
14123 (_conv.func_) is used in place of A for type deduction;
14126 --If A is a cv-qualified type, the top level
14127 cv-qualifiers of A's type are ignored for type
14129 if (TREE_CODE (*arg) == ARRAY_TYPE)
14130 *arg = build_pointer_type (TREE_TYPE (*arg));
14131 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14132 *arg = build_pointer_type (*arg);
14134 *arg = TYPE_MAIN_VARIANT (*arg);
14137 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14138 of the form T&&, where T is a template parameter, and the argument
14139 is an lvalue, T is deduced as A& */
14140 if (TREE_CODE (*parm) == REFERENCE_TYPE
14141 && TYPE_REF_IS_RVALUE (*parm)
14142 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14143 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14144 && (arg_expr ? real_lvalue_p (arg_expr)
14145 /* try_one_overload doesn't provide an arg_expr, but
14146 functions are always lvalues. */
14147 : TREE_CODE (*arg) == FUNCTION_TYPE))
14148 *arg = build_reference_type (*arg);
14150 /* [temp.deduct.call]
14152 If P is a cv-qualified type, the top level cv-qualifiers
14153 of P's type are ignored for type deduction. If P is a
14154 reference type, the type referred to by P is used for
14156 *parm = TYPE_MAIN_VARIANT (*parm);
14157 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14159 *parm = TREE_TYPE (*parm);
14160 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14163 /* DR 322. For conversion deduction, remove a reference type on parm
14164 too (which has been swapped into ARG). */
14165 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14166 *arg = TREE_TYPE (*arg);
14171 /* Most parms like fn_type_unification.
14173 If SUBR is 1, we're being called recursively (to unify the
14174 arguments of a function or method parameter of a function
14178 type_unification_real (tree tparms,
14182 unsigned int xnargs,
14184 unification_kind_t strict,
14187 tree parm, arg, arg_expr;
14189 int ntparms = TREE_VEC_LENGTH (tparms);
14191 int saw_undeduced = 0;
14194 unsigned int nargs;
14197 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14198 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14199 gcc_assert (ntparms > 0);
14201 /* Reset the number of non-defaulted template arguments contained
14203 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14208 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
14209 | UNIFY_ALLOW_DERIVED);
14213 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14217 sub_strict = UNIFY_ALLOW_NONE;
14221 gcc_unreachable ();
14230 while (parms && parms != void_list_node
14233 parm = TREE_VALUE (parms);
14235 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
14236 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
14237 /* For a function parameter pack that occurs at the end of the
14238 parameter-declaration-list, the type A of each remaining
14239 argument of the call is compared with the type P of the
14240 declarator-id of the function parameter pack. */
14243 parms = TREE_CHAIN (parms);
14245 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
14246 /* For a function parameter pack that does not occur at the
14247 end of the parameter-declaration-list, the type of the
14248 parameter pack is a non-deduced context. */
14255 if (arg == error_mark_node)
14257 if (arg == unknown_type_node)
14258 /* We can't deduce anything from this, but we might get all the
14259 template args from other function args. */
14262 /* Conversions will be performed on a function argument that
14263 corresponds with a function parameter that contains only
14264 non-deducible template parameters and explicitly specified
14265 template parameters. */
14266 if (!uses_template_parms (parm))
14271 type = TREE_TYPE (arg);
14275 if (same_type_p (parm, type))
14277 if (strict != DEDUCE_EXACT
14278 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
14287 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14288 if (type_unknown_p (arg))
14290 /* [temp.deduct.type]
14292 A template-argument can be deduced from a pointer to
14293 function or pointer to member function argument if
14294 the set of overloaded functions does not contain
14295 function templates and at most one of a set of
14296 overloaded functions provides a unique match. */
14297 if (resolve_overloaded_unification
14298 (tparms, targs, parm, arg, strict, sub_strict))
14304 arg = unlowered_expr_type (arg);
14305 if (arg == error_mark_node)
14310 int arg_strict = sub_strict;
14313 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14316 if (arg == init_list_type_node && arg_expr)
14318 if (unify (tparms, targs, parm, arg, arg_strict))
14325 && parms != void_list_node
14326 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14328 /* Unify the remaining arguments with the pack expansion type. */
14330 tree parmvec = make_tree_vec (1);
14332 /* Allocate a TREE_VEC and copy in all of the arguments */
14333 argvec = make_tree_vec (nargs - ia);
14334 for (i = 0; ia < nargs; ++ia, ++i)
14335 TREE_VEC_ELT (argvec, i) = args[ia];
14337 /* Copy the parameter into parmvec. */
14338 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14339 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14340 /*call_args_p=*/true, /*subr=*/subr))
14343 /* Advance to the end of the list of parameters. */
14344 parms = TREE_CHAIN (parms);
14347 /* Fail if we've reached the end of the parm list, and more args
14348 are present, and the parm list isn't variadic. */
14349 if (ia < nargs && parms == void_list_node)
14351 /* Fail if parms are left and they don't have default values. */
14352 if (parms && parms != void_list_node
14353 && TREE_PURPOSE (parms) == NULL_TREE)
14358 /* Check to see if we need another pass before we start clearing
14359 ARGUMENT_PACK_INCOMPLETE_P. */
14360 for (i = 0; i < ntparms; i++)
14362 tree targ = TREE_VEC_ELT (targs, i);
14363 tree tparm = TREE_VEC_ELT (tparms, i);
14365 if (targ || tparm == error_mark_node)
14367 tparm = TREE_VALUE (tparm);
14369 /* If this is an undeduced nontype parameter that depends on
14370 a type parameter, try another pass; its type may have been
14371 deduced from a later argument than the one from which
14372 this parameter can be deduced. */
14373 if (TREE_CODE (tparm) == PARM_DECL
14374 && uses_template_parms (TREE_TYPE (tparm))
14375 && !saw_undeduced++)
14379 for (i = 0; i < ntparms; i++)
14381 tree targ = TREE_VEC_ELT (targs, i);
14382 tree tparm = TREE_VEC_ELT (tparms, i);
14384 /* Clear the "incomplete" flags on all argument packs now so that
14385 substituting them into later default arguments works. */
14386 if (targ && ARGUMENT_PACK_P (targ))
14388 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14389 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14392 if (targ || tparm == error_mark_node)
14394 tparm = TREE_VALUE (tparm);
14396 /* Core issue #226 (C++0x) [temp.deduct]:
14398 If a template argument has not been deduced, its
14399 default template argument, if any, is used.
14401 When we are in C++98 mode, TREE_PURPOSE will either
14402 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14403 to explicitly check cxx_dialect here. */
14404 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14406 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14407 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14408 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14409 arg = convert_template_argument (parm, arg, targs, tf_none,
14411 if (arg == error_mark_node)
14415 TREE_VEC_ELT (targs, i) = arg;
14416 /* The position of the first default template argument,
14417 is also the number of non-defaulted arguments in TARGS.
14419 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14420 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14425 /* If the type parameter is a parameter pack, then it will
14426 be deduced to an empty parameter pack. */
14427 if (template_parameter_pack_p (tparm))
14431 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14433 arg = make_node (NONTYPE_ARGUMENT_PACK);
14434 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14435 TREE_CONSTANT (arg) = 1;
14438 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14440 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14442 TREE_VEC_ELT (targs, i) = arg;
14449 #ifdef ENABLE_CHECKING
14450 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14451 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14457 /* Subroutine of type_unification_real. Args are like the variables
14458 at the call site. ARG is an overloaded function (or template-id);
14459 we try deducing template args from each of the overloads, and if
14460 only one succeeds, we go with that. Modifies TARGS and returns
14461 true on success. */
14464 resolve_overloaded_unification (tree tparms,
14468 unification_kind_t strict,
14471 tree tempargs = copy_node (targs);
14473 tree goodfn = NULL_TREE;
14476 if (TREE_CODE (arg) == ADDR_EXPR)
14478 arg = TREE_OPERAND (arg, 0);
14484 if (TREE_CODE (arg) == COMPONENT_REF)
14485 /* Handle `&x' where `x' is some static or non-static member
14487 arg = TREE_OPERAND (arg, 1);
14489 if (TREE_CODE (arg) == OFFSET_REF)
14490 arg = TREE_OPERAND (arg, 1);
14492 /* Strip baselink information. */
14493 if (BASELINK_P (arg))
14494 arg = BASELINK_FUNCTIONS (arg);
14496 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14498 /* If we got some explicit template args, we need to plug them into
14499 the affected templates before we try to unify, in case the
14500 explicit args will completely resolve the templates in question. */
14502 tree expl_subargs = TREE_OPERAND (arg, 1);
14503 arg = TREE_OPERAND (arg, 0);
14505 for (; arg; arg = OVL_NEXT (arg))
14507 tree fn = OVL_CURRENT (arg);
14508 tree subargs, elem;
14510 if (TREE_CODE (fn) != TEMPLATE_DECL)
14513 ++processing_template_decl;
14514 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14515 expl_subargs, /*check_ret=*/false);
14518 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14519 if (try_one_overload (tparms, targs, tempargs, parm,
14520 elem, strict, sub_strict, addr_p)
14521 && (!goodfn || !decls_match (goodfn, elem)))
14527 --processing_template_decl;
14530 else if (TREE_CODE (arg) != OVERLOAD
14531 && TREE_CODE (arg) != FUNCTION_DECL)
14532 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14533 -- but the deduction does not succeed because the expression is
14534 not just the function on its own. */
14537 for (; arg; arg = OVL_NEXT (arg))
14538 if (try_one_overload (tparms, targs, tempargs, parm,
14539 TREE_TYPE (OVL_CURRENT (arg)),
14540 strict, sub_strict, addr_p)
14541 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
14543 goodfn = OVL_CURRENT (arg);
14547 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14548 to function or pointer to member function argument if the set of
14549 overloaded functions does not contain function templates and at most
14550 one of a set of overloaded functions provides a unique match.
14552 So if we found multiple possibilities, we return success but don't
14553 deduce anything. */
14557 int i = TREE_VEC_LENGTH (targs);
14559 if (TREE_VEC_ELT (tempargs, i))
14560 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
14568 /* Core DR 115: In contexts where deduction is done and fails, or in
14569 contexts where deduction is not done, if a template argument list is
14570 specified and it, along with any default template arguments, identifies
14571 a single function template specialization, then the template-id is an
14572 lvalue for the function template specialization. */
14575 resolve_nondeduced_context (tree orig_expr)
14577 tree expr, offset, baselink;
14580 if (!type_unknown_p (orig_expr))
14585 offset = NULL_TREE;
14586 baselink = NULL_TREE;
14588 if (TREE_CODE (expr) == ADDR_EXPR)
14590 expr = TREE_OPERAND (expr, 0);
14593 if (TREE_CODE (expr) == OFFSET_REF)
14596 expr = TREE_OPERAND (expr, 1);
14598 if (TREE_CODE (expr) == BASELINK)
14601 expr = BASELINK_FUNCTIONS (expr);
14604 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
14607 tree goodfn = NULL_TREE;
14609 /* If we got some explicit template args, we need to plug them into
14610 the affected templates before we try to unify, in case the
14611 explicit args will completely resolve the templates in question. */
14613 tree expl_subargs = TREE_OPERAND (expr, 1);
14614 tree arg = TREE_OPERAND (expr, 0);
14615 tree badfn = NULL_TREE;
14616 tree badargs = NULL_TREE;
14618 for (; arg; arg = OVL_NEXT (arg))
14620 tree fn = OVL_CURRENT (arg);
14621 tree subargs, elem;
14623 if (TREE_CODE (fn) != TEMPLATE_DECL)
14626 ++processing_template_decl;
14627 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14628 expl_subargs, /*check_ret=*/false);
14629 if (subargs && !any_dependent_template_arguments_p (subargs))
14631 elem = instantiate_template (fn, subargs, tf_none);
14632 if (elem == error_mark_node)
14637 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
14643 --processing_template_decl;
14649 expr = build_baselink (BASELINK_BINFO (baselink),
14650 BASELINK_ACCESS_BINFO (baselink),
14651 expr, BASELINK_OPTYPE (baselink));
14655 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
14656 expr = build_offset_ref (base, expr, addr);
14659 expr = cp_build_addr_expr (expr, tf_warning_or_error);
14662 else if (good == 0 && badargs)
14663 /* There were no good options and at least one bad one, so let the
14664 user know what the problem is. */
14665 instantiate_template (badfn, badargs, tf_warning_or_error);
14670 /* Subroutine of resolve_overloaded_unification; does deduction for a single
14671 overload. Fills TARGS with any deduced arguments, or error_mark_node if
14672 different overloads deduce different arguments for a given parm.
14673 ADDR_P is true if the expression for which deduction is being
14674 performed was of the form "& fn" rather than simply "fn".
14676 Returns 1 on success. */
14679 try_one_overload (tree tparms,
14684 unification_kind_t strict,
14692 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14693 to function or pointer to member function argument if the set of
14694 overloaded functions does not contain function templates and at most
14695 one of a set of overloaded functions provides a unique match.
14697 So if this is a template, just return success. */
14699 if (uses_template_parms (arg))
14702 if (TREE_CODE (arg) == METHOD_TYPE)
14703 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14705 arg = build_pointer_type (arg);
14707 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14709 /* We don't copy orig_targs for this because if we have already deduced
14710 some template args from previous args, unify would complain when we
14711 try to deduce a template parameter for the same argument, even though
14712 there isn't really a conflict. */
14713 nargs = TREE_VEC_LENGTH (targs);
14714 tempargs = make_tree_vec (nargs);
14716 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14719 /* First make sure we didn't deduce anything that conflicts with
14720 explicitly specified args. */
14721 for (i = nargs; i--; )
14723 tree elt = TREE_VEC_ELT (tempargs, i);
14724 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14728 else if (uses_template_parms (elt))
14729 /* Since we're unifying against ourselves, we will fill in
14730 template args used in the function parm list with our own
14731 template parms. Discard them. */
14732 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14733 else if (oldelt && !template_args_equal (oldelt, elt))
14737 for (i = nargs; i--; )
14739 tree elt = TREE_VEC_ELT (tempargs, i);
14742 TREE_VEC_ELT (targs, i) = elt;
14748 /* PARM is a template class (perhaps with unbound template
14749 parameters). ARG is a fully instantiated type. If ARG can be
14750 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14751 TARGS are as for unify. */
14754 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14756 tree copy_of_targs;
14758 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14759 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14760 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14763 /* We need to make a new template argument vector for the call to
14764 unify. If we used TARGS, we'd clutter it up with the result of
14765 the attempted unification, even if this class didn't work out.
14766 We also don't want to commit ourselves to all the unifications
14767 we've already done, since unification is supposed to be done on
14768 an argument-by-argument basis. In other words, consider the
14769 following pathological case:
14771 template <int I, int J, int K>
14774 template <int I, int J>
14775 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14777 template <int I, int J, int K>
14778 void f(S<I, J, K>, S<I, I, I>);
14787 Now, by the time we consider the unification involving `s2', we
14788 already know that we must have `f<0, 0, 0>'. But, even though
14789 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14790 because there are two ways to unify base classes of S<0, 1, 2>
14791 with S<I, I, I>. If we kept the already deduced knowledge, we
14792 would reject the possibility I=1. */
14793 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14795 /* If unification failed, we're done. */
14796 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14797 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14803 /* Given a template type PARM and a class type ARG, find the unique
14804 base type in ARG that is an instance of PARM. We do not examine
14805 ARG itself; only its base-classes. If there is not exactly one
14806 appropriate base class, return NULL_TREE. PARM may be the type of
14807 a partial specialization, as well as a plain template type. Used
14811 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14813 tree rval = NULL_TREE;
14816 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14818 binfo = TYPE_BINFO (complete_type (arg));
14820 /* The type could not be completed. */
14823 /* Walk in inheritance graph order. The search order is not
14824 important, and this avoids multiple walks of virtual bases. */
14825 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14827 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14831 /* If there is more than one satisfactory baseclass, then:
14835 If they yield more than one possible deduced A, the type
14839 if (rval && !same_type_p (r, rval))
14849 /* Returns the level of DECL, which declares a template parameter. */
14852 template_decl_level (tree decl)
14854 switch (TREE_CODE (decl))
14857 case TEMPLATE_DECL:
14858 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14861 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14864 gcc_unreachable ();
14869 /* Decide whether ARG can be unified with PARM, considering only the
14870 cv-qualifiers of each type, given STRICT as documented for unify.
14871 Returns nonzero iff the unification is OK on that basis. */
14874 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14876 int arg_quals = cp_type_quals (arg);
14877 int parm_quals = cp_type_quals (parm);
14879 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14880 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14882 /* Although a CVR qualifier is ignored when being applied to a
14883 substituted template parameter ([8.3.2]/1 for example), that
14884 does not allow us to unify "const T" with "int&" because both
14885 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14886 It is ok when we're allowing additional CV qualifiers
14887 at the outer level [14.8.2.1]/3,1st bullet. */
14888 if ((TREE_CODE (arg) == REFERENCE_TYPE
14889 || TREE_CODE (arg) == FUNCTION_TYPE
14890 || TREE_CODE (arg) == METHOD_TYPE)
14891 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14894 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14895 && (parm_quals & TYPE_QUAL_RESTRICT))
14899 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14900 && (arg_quals & parm_quals) != parm_quals)
14903 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14904 && (parm_quals & arg_quals) != arg_quals)
14910 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14912 template_parm_level_and_index (tree parm, int* level, int* index)
14914 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14915 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14916 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14918 *index = TEMPLATE_TYPE_IDX (parm);
14919 *level = TEMPLATE_TYPE_LEVEL (parm);
14923 *index = TEMPLATE_PARM_IDX (parm);
14924 *level = TEMPLATE_PARM_LEVEL (parm);
14928 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14929 expansion at the end of PACKED_PARMS. Returns 0 if the type
14930 deduction succeeds, 1 otherwise. STRICT is the same as in
14931 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14932 call argument list. We'll need to adjust the arguments to make them
14933 types. SUBR tells us if this is from a recursive call to
14934 type_unification_real. */
14936 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14937 tree packed_args, int strict, bool call_args_p,
14941 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14942 tree pattern = PACK_EXPANSION_PATTERN (parm);
14943 tree pack, packs = NULL_TREE;
14944 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14945 int len = TREE_VEC_LENGTH (packed_args);
14947 /* Determine the parameter packs we will be deducing from the
14948 pattern, and record their current deductions. */
14949 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14950 pack; pack = TREE_CHAIN (pack))
14952 tree parm_pack = TREE_VALUE (pack);
14955 /* Determine the index and level of this parameter pack. */
14956 template_parm_level_and_index (parm_pack, &level, &idx);
14958 /* Keep track of the parameter packs and their corresponding
14960 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14961 TREE_TYPE (packs) = make_tree_vec (len - start);
14964 /* Loop through all of the arguments that have not yet been
14965 unified and unify each with the pattern. */
14966 for (i = start; i < len; i++)
14968 tree parm = pattern;
14970 /* For each parameter pack, clear out the deduced value so that
14971 we can deduce it again. */
14972 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14975 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14977 TMPL_ARG (targs, level, idx) = NULL_TREE;
14980 /* Unify the pattern with the current argument. */
14982 tree arg = TREE_VEC_ELT (packed_args, i);
14983 tree arg_expr = NULL_TREE;
14984 int arg_strict = strict;
14985 bool skip_arg_p = false;
14991 /* This mirrors what we do in type_unification_real. */
14995 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14996 | UNIFY_ALLOW_MORE_CV_QUAL
14997 | UNIFY_ALLOW_DERIVED);
15001 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15005 sub_strict = UNIFY_ALLOW_NONE;
15009 gcc_unreachable ();
15014 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15015 if (type_unknown_p (arg))
15017 /* [temp.deduct.type] A template-argument can be
15018 deduced from a pointer to function or pointer
15019 to member function argument if the set of
15020 overloaded functions does not contain function
15021 templates and at most one of a set of
15022 overloaded functions provides a unique
15025 if (resolve_overloaded_unification
15026 (tparms, targs, parm, arg,
15027 (unification_kind_t) strict,
15037 arg = unlowered_expr_type (arg);
15038 if (arg == error_mark_node)
15043 arg_strict = sub_strict;
15047 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
15048 &parm, &arg, arg_expr);
15053 /* For deduction from an init-list we need the actual list. */
15054 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15056 if (unify (tparms, targs, parm, arg, arg_strict))
15061 /* For each parameter pack, collect the deduced value. */
15062 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15065 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15067 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15068 TMPL_ARG (targs, level, idx);
15072 /* Verify that the results of unification with the parameter packs
15073 produce results consistent with what we've seen before, and make
15074 the deduced argument packs available. */
15075 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15077 tree old_pack = TREE_VALUE (pack);
15078 tree new_args = TREE_TYPE (pack);
15079 int i, len = TREE_VEC_LENGTH (new_args);
15081 bool nondeduced_p = false;
15083 /* By default keep the original deduced argument pack.
15084 If necessary, more specific code is going to update the
15085 resulting deduced argument later down in this function. */
15086 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15087 TMPL_ARG (targs, level, idx) = old_pack;
15089 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15090 actually deduce anything. */
15091 for (i = 0; i < len && !nondeduced_p; ++i)
15092 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15093 nondeduced_p = true;
15097 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15099 /* Prepend the explicit arguments onto NEW_ARGS. */
15100 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15101 tree old_args = new_args;
15102 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
15103 int len = explicit_len + TREE_VEC_LENGTH (old_args);
15105 /* Copy the explicit arguments. */
15106 new_args = make_tree_vec (len);
15107 for (i = 0; i < explicit_len; i++)
15108 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
15110 /* Copy the deduced arguments. */
15111 for (; i < len; i++)
15112 TREE_VEC_ELT (new_args, i) =
15113 TREE_VEC_ELT (old_args, i - explicit_len);
15119 /* Build the deduced *_ARGUMENT_PACK. */
15120 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15122 result = make_node (NONTYPE_ARGUMENT_PACK);
15123 TREE_TYPE (result) =
15124 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15125 TREE_CONSTANT (result) = 1;
15128 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15130 SET_ARGUMENT_PACK_ARGS (result, new_args);
15132 /* Note the deduced argument packs for this parameter
15134 TMPL_ARG (targs, level, idx) = result;
15136 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15137 && (ARGUMENT_PACK_ARGS (old_pack)
15138 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15140 /* We only had the explicitly-provided arguments before, but
15141 now we have a complete set of arguments. */
15142 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15144 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15145 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15146 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15148 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
15150 /* Inconsistent unification of this parameter pack. */
15157 /* Deduce the value of template parameters. TPARMS is the (innermost)
15158 set of template parameters to a template. TARGS is the bindings
15159 for those template parameters, as determined thus far; TARGS may
15160 include template arguments for outer levels of template parameters
15161 as well. PARM is a parameter to a template function, or a
15162 subcomponent of that parameter; ARG is the corresponding argument.
15163 This function attempts to match PARM with ARG in a manner
15164 consistent with the existing assignments in TARGS. If more values
15165 are deduced, then TARGS is updated.
15167 Returns 0 if the type deduction succeeds, 1 otherwise. The
15168 parameter STRICT is a bitwise or of the following flags:
15171 Require an exact match between PARM and ARG.
15172 UNIFY_ALLOW_MORE_CV_QUAL:
15173 Allow the deduced ARG to be more cv-qualified (by qualification
15174 conversion) than ARG.
15175 UNIFY_ALLOW_LESS_CV_QUAL:
15176 Allow the deduced ARG to be less cv-qualified than ARG.
15177 UNIFY_ALLOW_DERIVED:
15178 Allow the deduced ARG to be a template base class of ARG,
15179 or a pointer to a template base class of the type pointed to by
15181 UNIFY_ALLOW_INTEGER:
15182 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15183 case for more information.
15184 UNIFY_ALLOW_OUTER_LEVEL:
15185 This is the outermost level of a deduction. Used to determine validity
15186 of qualification conversions. A valid qualification conversion must
15187 have const qualified pointers leading up to the inner type which
15188 requires additional CV quals, except at the outer level, where const
15189 is not required [conv.qual]. It would be normal to set this flag in
15190 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15191 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15192 This is the outermost level of a deduction, and PARM can be more CV
15193 qualified at this point.
15194 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15195 This is the outermost level of a deduction, and PARM can be less CV
15196 qualified at this point. */
15199 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
15204 int strict_in = strict;
15206 /* I don't think this will do the right thing with respect to types.
15207 But the only case I've seen it in so far has been array bounds, where
15208 signedness is the only information lost, and I think that will be
15210 while (TREE_CODE (parm) == NOP_EXPR)
15211 parm = TREE_OPERAND (parm, 0);
15213 if (arg == error_mark_node)
15215 if (arg == unknown_type_node
15216 || arg == init_list_type_node)
15217 /* We can't deduce anything from this, but we might get all the
15218 template args from other function args. */
15221 /* If PARM uses template parameters, then we can't bail out here,
15222 even if ARG == PARM, since we won't record unifications for the
15223 template parameters. We might need them if we're trying to
15224 figure out which of two things is more specialized. */
15225 if (arg == parm && !uses_template_parms (parm))
15228 /* Handle init lists early, so the rest of the function can assume
15229 we're dealing with a type. */
15230 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15234 tree orig_parm = parm;
15236 /* Replace T with std::initializer_list<T> for deduction. */
15237 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15238 && flag_deduce_init_list)
15239 parm = listify (parm);
15241 if (!is_std_init_list (parm))
15242 /* We can only deduce from an initializer list argument if the
15243 parameter is std::initializer_list; otherwise this is a
15244 non-deduced context. */
15247 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15249 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15251 int elt_strict = strict;
15253 if (elt == error_mark_node)
15256 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15258 tree type = TREE_TYPE (elt);
15259 /* It should only be possible to get here for a call. */
15260 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15261 elt_strict |= maybe_adjust_types_for_deduction
15262 (DEDUCE_CALL, &elttype, &type, elt);
15266 if (unify (tparms, targs, elttype, elt, elt_strict))
15270 /* If the std::initializer_list<T> deduction worked, replace the
15271 deduced A with std::initializer_list<A>. */
15272 if (orig_parm != parm)
15274 idx = TEMPLATE_TYPE_IDX (orig_parm);
15275 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15276 targ = listify (targ);
15277 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15282 /* Immediately reject some pairs that won't unify because of
15283 cv-qualification mismatches. */
15284 if (TREE_CODE (arg) == TREE_CODE (parm)
15286 /* It is the elements of the array which hold the cv quals of an array
15287 type, and the elements might be template type parms. We'll check
15288 when we recurse. */
15289 && TREE_CODE (arg) != ARRAY_TYPE
15290 /* We check the cv-qualifiers when unifying with template type
15291 parameters below. We want to allow ARG `const T' to unify with
15292 PARM `T' for example, when computing which of two templates
15293 is more specialized, for example. */
15294 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15295 && !check_cv_quals_for_unify (strict_in, arg, parm))
15298 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15299 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15300 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15301 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15302 strict &= ~UNIFY_ALLOW_DERIVED;
15303 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15304 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15306 switch (TREE_CODE (parm))
15308 case TYPENAME_TYPE:
15310 case UNBOUND_CLASS_TEMPLATE:
15311 /* In a type which contains a nested-name-specifier, template
15312 argument values cannot be deduced for template parameters used
15313 within the nested-name-specifier. */
15316 case TEMPLATE_TYPE_PARM:
15317 case TEMPLATE_TEMPLATE_PARM:
15318 case BOUND_TEMPLATE_TEMPLATE_PARM:
15319 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15320 if (tparm == error_mark_node)
15323 if (TEMPLATE_TYPE_LEVEL (parm)
15324 != template_decl_level (tparm))
15325 /* The PARM is not one we're trying to unify. Just check
15326 to see if it matches ARG. */
15327 return (TREE_CODE (arg) == TREE_CODE (parm)
15328 && same_type_p (parm, arg)) ? 0 : 1;
15329 idx = TEMPLATE_TYPE_IDX (parm);
15330 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15331 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15333 /* Check for mixed types and values. */
15334 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15335 && TREE_CODE (tparm) != TYPE_DECL)
15336 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15337 && TREE_CODE (tparm) != TEMPLATE_DECL))
15340 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15342 /* ARG must be constructed from a template class or a template
15343 template parameter. */
15344 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15345 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15349 tree parmvec = TYPE_TI_ARGS (parm);
15350 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15351 tree full_argvec = add_to_template_args (targs, argvec);
15353 = DECL_INNERMOST_TEMPLATE_PARMS
15354 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15356 int parm_variadic_p = 0;
15358 /* The resolution to DR150 makes clear that default
15359 arguments for an N-argument may not be used to bind T
15360 to a template template parameter with fewer than N
15361 parameters. It is not safe to permit the binding of
15362 default arguments as an extension, as that may change
15363 the meaning of a conforming program. Consider:
15365 struct Dense { static const unsigned int dim = 1; };
15367 template <template <typename> class View,
15369 void operator+(float, View<Block> const&);
15371 template <typename Block,
15372 unsigned int Dim = Block::dim>
15373 struct Lvalue_proxy { operator float() const; };
15377 Lvalue_proxy<Dense> p;
15382 Here, if Lvalue_proxy is permitted to bind to View, then
15383 the global operator+ will be used; if they are not, the
15384 Lvalue_proxy will be converted to float. */
15385 if (coerce_template_parms (parm_parms,
15387 TYPE_TI_TEMPLATE (parm),
15389 /*require_all_args=*/true,
15390 /*use_default_args=*/false)
15391 == error_mark_node)
15394 /* Deduce arguments T, i from TT<T> or TT<i>.
15395 We check each element of PARMVEC and ARGVEC individually
15396 rather than the whole TREE_VEC since they can have
15397 different number of elements. */
15399 parmvec = expand_template_argument_pack (parmvec);
15400 argvec = expand_template_argument_pack (argvec);
15402 len = TREE_VEC_LENGTH (parmvec);
15404 /* Check if the parameters end in a pack, making them
15407 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15408 parm_variadic_p = 1;
15410 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15413 for (i = 0; i < len - parm_variadic_p; ++i)
15415 if (unify (tparms, targs,
15416 TREE_VEC_ELT (parmvec, i),
15417 TREE_VEC_ELT (argvec, i),
15422 if (parm_variadic_p
15423 && unify_pack_expansion (tparms, targs,
15426 /*call_args_p=*/false,
15430 arg = TYPE_TI_TEMPLATE (arg);
15432 /* Fall through to deduce template name. */
15435 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15436 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15438 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15440 /* Simple cases: Value already set, does match or doesn't. */
15441 if (targ != NULL_TREE && template_args_equal (targ, arg))
15448 /* If PARM is `const T' and ARG is only `int', we don't have
15449 a match unless we are allowing additional qualification.
15450 If ARG is `const int' and PARM is just `T' that's OK;
15451 that binds `const int' to `T'. */
15452 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15456 /* Consider the case where ARG is `const volatile int' and
15457 PARM is `const T'. Then, T should be `volatile int'. */
15458 arg = cp_build_qualified_type_real
15459 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15460 if (arg == error_mark_node)
15463 /* Simple cases: Value already set, does match or doesn't. */
15464 if (targ != NULL_TREE && same_type_p (targ, arg))
15469 /* Make sure that ARG is not a variable-sized array. (Note
15470 that were talking about variable-sized arrays (like
15471 `int[n]'), rather than arrays of unknown size (like
15472 `int[]').) We'll get very confused by such a type since
15473 the bound of the array will not be computable in an
15474 instantiation. Besides, such types are not allowed in
15475 ISO C++, so we can do as we please here. */
15476 if (variably_modified_type_p (arg, NULL_TREE))
15479 /* Strip typedefs as in convert_template_argument. */
15480 arg = strip_typedefs (arg);
15483 /* If ARG is a parameter pack or an expansion, we cannot unify
15484 against it unless PARM is also a parameter pack. */
15485 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15486 && !template_parameter_pack_p (parm))
15489 /* If the argument deduction results is a METHOD_TYPE,
15490 then there is a problem.
15491 METHOD_TYPE doesn't map to any real C++ type the result of
15492 the deduction can not be of that type. */
15493 if (TREE_CODE (arg) == METHOD_TYPE)
15496 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15499 case TEMPLATE_PARM_INDEX:
15500 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15501 if (tparm == error_mark_node)
15504 if (TEMPLATE_PARM_LEVEL (parm)
15505 != template_decl_level (tparm))
15506 /* The PARM is not one we're trying to unify. Just check
15507 to see if it matches ARG. */
15508 return !(TREE_CODE (arg) == TREE_CODE (parm)
15509 && cp_tree_equal (parm, arg));
15511 idx = TEMPLATE_PARM_IDX (parm);
15512 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15515 return !cp_tree_equal (targ, arg);
15517 /* [temp.deduct.type] If, in the declaration of a function template
15518 with a non-type template-parameter, the non-type
15519 template-parameter is used in an expression in the function
15520 parameter-list and, if the corresponding template-argument is
15521 deduced, the template-argument type shall match the type of the
15522 template-parameter exactly, except that a template-argument
15523 deduced from an array bound may be of any integral type.
15524 The non-type parameter might use already deduced type parameters. */
15525 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
15526 if (!TREE_TYPE (arg))
15527 /* Template-parameter dependent expression. Just accept it for now.
15528 It will later be processed in convert_template_argument. */
15530 else if (same_type_p (TREE_TYPE (arg), tparm))
15532 else if ((strict & UNIFY_ALLOW_INTEGER)
15533 && (TREE_CODE (tparm) == INTEGER_TYPE
15534 || TREE_CODE (tparm) == BOOLEAN_TYPE))
15535 /* Convert the ARG to the type of PARM; the deduced non-type
15536 template argument must exactly match the types of the
15537 corresponding parameter. */
15538 arg = fold (build_nop (tparm, arg));
15539 else if (uses_template_parms (tparm))
15540 /* We haven't deduced the type of this parameter yet. Try again
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_PARM_PARAMETER_PACK (parm))
15552 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15557 /* A pointer-to-member constant can be unified only with
15558 another constant. */
15559 if (TREE_CODE (arg) != PTRMEM_CST)
15562 /* Just unify the class member. It would be useless (and possibly
15563 wrong, depending on the strict flags) to unify also
15564 PTRMEM_CST_CLASS, because we want to be sure that both parm and
15565 arg refer to the same variable, even if through different
15566 classes. For instance:
15568 struct A { int x; };
15571 Unification of &A::x and &B::x must succeed. */
15572 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
15573 PTRMEM_CST_MEMBER (arg), strict);
15578 if (TREE_CODE (arg) != POINTER_TYPE)
15581 /* [temp.deduct.call]
15583 A can be another pointer or pointer to member type that can
15584 be converted to the deduced A via a qualification
15585 conversion (_conv.qual_).
15587 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
15588 This will allow for additional cv-qualification of the
15589 pointed-to types if appropriate. */
15591 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
15592 /* The derived-to-base conversion only persists through one
15593 level of pointers. */
15594 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
15596 return unify (tparms, targs, TREE_TYPE (parm),
15597 TREE_TYPE (arg), strict);
15600 case REFERENCE_TYPE:
15601 if (TREE_CODE (arg) != REFERENCE_TYPE)
15603 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15604 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15607 if (TREE_CODE (arg) != ARRAY_TYPE)
15609 if ((TYPE_DOMAIN (parm) == NULL_TREE)
15610 != (TYPE_DOMAIN (arg) == NULL_TREE))
15612 if (TYPE_DOMAIN (parm) != NULL_TREE)
15619 /* Our representation of array types uses "N - 1" as the
15620 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
15621 not an integer constant. We cannot unify arbitrarily
15622 complex expressions, so we eliminate the MINUS_EXPRs
15624 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
15625 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
15628 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
15629 parm_max = TREE_OPERAND (parm_max, 0);
15631 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
15632 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
15635 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
15636 trying to unify the type of a variable with the type
15637 of a template parameter. For example:
15639 template <unsigned int N>
15640 void f (char (&) [N]);
15647 Here, the type of the ARG will be "int [g(i)]", and
15648 may be a SAVE_EXPR, etc. */
15649 if (TREE_CODE (arg_max) != MINUS_EXPR)
15651 arg_max = TREE_OPERAND (arg_max, 0);
15654 /* If only one of the bounds used a MINUS_EXPR, compensate
15655 by adding one to the other bound. */
15656 if (parm_cst && !arg_cst)
15657 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
15661 else if (arg_cst && !parm_cst)
15662 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
15667 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
15670 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15671 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15678 case ENUMERAL_TYPE:
15680 if (TREE_CODE (arg) != TREE_CODE (parm))
15683 /* We have already checked cv-qualification at the top of the
15685 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15688 /* As far as unification is concerned, this wins. Later checks
15689 will invalidate it if necessary. */
15692 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15693 /* Type INTEGER_CST can come from ordinary constant template args. */
15695 while (TREE_CODE (arg) == NOP_EXPR)
15696 arg = TREE_OPERAND (arg, 0);
15698 if (TREE_CODE (arg) != INTEGER_CST)
15700 return !tree_int_cst_equal (parm, arg);
15705 if (TREE_CODE (arg) != TREE_VEC)
15707 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15709 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15710 if (unify (tparms, targs,
15711 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15719 if (TREE_CODE (arg) != TREE_CODE (parm))
15722 if (TYPE_PTRMEMFUNC_P (parm))
15724 if (!TYPE_PTRMEMFUNC_P (arg))
15727 return unify (tparms, targs,
15728 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15729 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15733 if (CLASSTYPE_TEMPLATE_INFO (parm))
15735 tree t = NULL_TREE;
15737 if (strict_in & UNIFY_ALLOW_DERIVED)
15739 /* First, we try to unify the PARM and ARG directly. */
15740 t = try_class_unification (tparms, targs,
15745 /* Fallback to the special case allowed in
15746 [temp.deduct.call]:
15748 If P is a class, and P has the form
15749 template-id, then A can be a derived class of
15750 the deduced A. Likewise, if P is a pointer to
15751 a class of the form template-id, A can be a
15752 pointer to a derived class pointed to by the
15754 t = get_template_base (tparms, targs, parm, arg);
15760 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15761 && (CLASSTYPE_TI_TEMPLATE (parm)
15762 == CLASSTYPE_TI_TEMPLATE (arg)))
15763 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15764 Then, we should unify `int' and `U'. */
15767 /* There's no chance of unification succeeding. */
15770 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15771 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15773 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15778 case FUNCTION_TYPE:
15780 unsigned int nargs;
15785 if (TREE_CODE (arg) != TREE_CODE (parm))
15788 /* CV qualifications for methods can never be deduced, they must
15789 match exactly. We need to check them explicitly here,
15790 because type_unification_real treats them as any other
15791 cv-qualified parameter. */
15792 if (TREE_CODE (parm) == METHOD_TYPE
15793 && (!check_cv_quals_for_unify
15795 class_of_this_parm (arg),
15796 class_of_this_parm (parm))))
15799 if (unify (tparms, targs, TREE_TYPE (parm),
15800 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15803 nargs = list_length (TYPE_ARG_TYPES (arg));
15804 args = XALLOCAVEC (tree, nargs);
15805 for (a = TYPE_ARG_TYPES (arg), i = 0;
15806 a != NULL_TREE && a != void_list_node;
15807 a = TREE_CHAIN (a), ++i)
15808 args[i] = TREE_VALUE (a);
15811 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15812 args, nargs, 1, DEDUCE_EXACT,
15817 /* Unify a pointer to member with a pointer to member function, which
15818 deduces the type of the member as a function type. */
15819 if (TYPE_PTRMEMFUNC_P (arg))
15824 /* Check top-level cv qualifiers */
15825 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15828 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15829 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15832 /* Determine the type of the function we are unifying against. */
15833 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15835 build_function_type (TREE_TYPE (method_type),
15836 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15838 /* Extract the cv-qualifiers of the member function from the
15839 implicit object parameter and place them on the function
15840 type to be restored later. */
15841 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15842 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15845 if (TREE_CODE (arg) != OFFSET_TYPE)
15847 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15848 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15850 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15854 if (DECL_TEMPLATE_PARM_P (parm))
15855 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15856 if (arg != integral_constant_value (parm))
15861 case TEMPLATE_DECL:
15862 /* Matched cases are handled by the ARG == PARM test above. */
15866 /* A non-type template parameter that is a variable should be a
15867 an integral constant, in which case, it whould have been
15868 folded into its (constant) value. So we should not be getting
15869 a variable here. */
15870 gcc_unreachable ();
15872 case TYPE_ARGUMENT_PACK:
15873 case NONTYPE_ARGUMENT_PACK:
15875 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15876 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15877 int i, len = TREE_VEC_LENGTH (packed_parms);
15878 int argslen = TREE_VEC_LENGTH (packed_args);
15879 int parm_variadic_p = 0;
15881 for (i = 0; i < len; ++i)
15883 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15886 /* We can unify against something with a trailing
15888 parm_variadic_p = 1;
15890 /* Since there is something following the pack
15891 expansion, we cannot unify this template argument
15898 /* If we don't have enough arguments to satisfy the parameters
15899 (not counting the pack expression at the end), or we have
15900 too many arguments for a parameter list that doesn't end in
15901 a pack expression, we can't unify. */
15902 if (argslen < (len - parm_variadic_p)
15903 || (argslen > len && !parm_variadic_p))
15906 /* Unify all of the parameters that precede the (optional)
15907 pack expression. */
15908 for (i = 0; i < len - parm_variadic_p; ++i)
15910 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15911 TREE_VEC_ELT (packed_args, i), strict))
15915 if (parm_variadic_p)
15916 return unify_pack_expansion (tparms, targs,
15917 packed_parms, packed_args,
15918 strict, /*call_args_p=*/false,
15926 case DECLTYPE_TYPE:
15927 case UNDERLYING_TYPE:
15928 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
15929 or UNDERLYING_TYPE nodes. */
15933 /* Unification fails if we hit an error node. */
15937 /* An unresolved overload is a nondeduced context. */
15938 if (type_unknown_p (parm))
15940 gcc_assert (EXPR_P (parm));
15942 /* We must be looking at an expression. This can happen with
15946 void foo(S<I>, S<I + 2>);
15948 This is a "nondeduced context":
15952 The nondeduced contexts are:
15954 --A type that is a template-id in which one or more of
15955 the template-arguments is an expression that references
15956 a template-parameter.
15958 In these cases, we assume deduction succeeded, but don't
15959 actually infer any unifications. */
15961 if (!uses_template_parms (parm)
15962 && !template_args_equal (parm, arg))
15969 /* Note that DECL can be defined in this translation unit, if
15973 mark_definable (tree decl)
15976 DECL_NOT_REALLY_EXTERN (decl) = 1;
15977 FOR_EACH_CLONE (clone, decl)
15978 DECL_NOT_REALLY_EXTERN (clone) = 1;
15981 /* Called if RESULT is explicitly instantiated, or is a member of an
15982 explicitly instantiated class. */
15985 mark_decl_instantiated (tree result, int extern_p)
15987 SET_DECL_EXPLICIT_INSTANTIATION (result);
15989 /* If this entity has already been written out, it's too late to
15990 make any modifications. */
15991 if (TREE_ASM_WRITTEN (result))
15994 if (TREE_CODE (result) != FUNCTION_DECL)
15995 /* The TREE_PUBLIC flag for function declarations will have been
15996 set correctly by tsubst. */
15997 TREE_PUBLIC (result) = 1;
15999 /* This might have been set by an earlier implicit instantiation. */
16000 DECL_COMDAT (result) = 0;
16003 DECL_NOT_REALLY_EXTERN (result) = 0;
16006 mark_definable (result);
16007 /* Always make artificials weak. */
16008 if (DECL_ARTIFICIAL (result) && flag_weak)
16009 comdat_linkage (result);
16010 /* For WIN32 we also want to put explicit instantiations in
16011 linkonce sections. */
16012 else if (TREE_PUBLIC (result))
16013 maybe_make_one_only (result);
16016 /* If EXTERN_P, then this function will not be emitted -- unless
16017 followed by an explicit instantiation, at which point its linkage
16018 will be adjusted. If !EXTERN_P, then this function will be
16019 emitted here. In neither circumstance do we want
16020 import_export_decl to adjust the linkage. */
16021 DECL_INTERFACE_KNOWN (result) = 1;
16024 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16025 important template arguments. If any are missing, we check whether
16026 they're important by using error_mark_node for substituting into any
16027 args that were used for partial ordering (the ones between ARGS and END)
16028 and seeing if it bubbles up. */
16031 check_undeduced_parms (tree targs, tree args, tree end)
16033 bool found = false;
16035 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16036 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16039 TREE_VEC_ELT (targs, i) = error_mark_node;
16043 for (; args != end; args = TREE_CHAIN (args))
16045 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16046 if (substed == error_mark_node)
16053 /* Given two function templates PAT1 and PAT2, return:
16055 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16056 -1 if PAT2 is more specialized than PAT1.
16057 0 if neither is more specialized.
16059 LEN indicates the number of parameters we should consider
16060 (defaulted parameters should not be considered).
16062 The 1998 std underspecified function template partial ordering, and
16063 DR214 addresses the issue. We take pairs of arguments, one from
16064 each of the templates, and deduce them against each other. One of
16065 the templates will be more specialized if all the *other*
16066 template's arguments deduce against its arguments and at least one
16067 of its arguments *does* *not* deduce against the other template's
16068 corresponding argument. Deduction is done as for class templates.
16069 The arguments used in deduction have reference and top level cv
16070 qualifiers removed. Iff both arguments were originally reference
16071 types *and* deduction succeeds in both directions, the template
16072 with the more cv-qualified argument wins for that pairing (if
16073 neither is more cv-qualified, they both are equal). Unlike regular
16074 deduction, after all the arguments have been deduced in this way,
16075 we do *not* verify the deduced template argument values can be
16076 substituted into non-deduced contexts.
16078 The logic can be a bit confusing here, because we look at deduce1 and
16079 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16080 can find template arguments for pat1 to make arg1 look like arg2, that
16081 means that arg2 is at least as specialized as arg1. */
16084 more_specialized_fn (tree pat1, tree pat2, int len)
16086 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16087 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16088 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16089 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16090 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16091 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16092 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16093 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16094 tree origs1, origs2;
16095 bool lose1 = false;
16096 bool lose2 = false;
16098 /* Remove the this parameter from non-static member functions. If
16099 one is a non-static member function and the other is not a static
16100 member function, remove the first parameter from that function
16101 also. This situation occurs for operator functions where we
16102 locate both a member function (with this pointer) and non-member
16103 operator (with explicit first operand). */
16104 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16106 len--; /* LEN is the number of significant arguments for DECL1 */
16107 args1 = TREE_CHAIN (args1);
16108 if (!DECL_STATIC_FUNCTION_P (decl2))
16109 args2 = TREE_CHAIN (args2);
16111 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16113 args2 = TREE_CHAIN (args2);
16114 if (!DECL_STATIC_FUNCTION_P (decl1))
16117 args1 = TREE_CHAIN (args1);
16121 /* If only one is a conversion operator, they are unordered. */
16122 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16125 /* Consider the return type for a conversion function */
16126 if (DECL_CONV_FN_P (decl1))
16128 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16129 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16133 processing_template_decl++;
16139 /* Stop when an ellipsis is seen. */
16140 && args1 != NULL_TREE && args2 != NULL_TREE)
16142 tree arg1 = TREE_VALUE (args1);
16143 tree arg2 = TREE_VALUE (args2);
16144 int deduce1, deduce2;
16148 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16149 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16151 /* When both arguments are pack expansions, we need only
16152 unify the patterns themselves. */
16153 arg1 = PACK_EXPANSION_PATTERN (arg1);
16154 arg2 = PACK_EXPANSION_PATTERN (arg2);
16156 /* This is the last comparison we need to do. */
16160 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16162 arg1 = TREE_TYPE (arg1);
16163 quals1 = cp_type_quals (arg1);
16166 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16168 arg2 = TREE_TYPE (arg2);
16169 quals2 = cp_type_quals (arg2);
16172 if ((quals1 < 0) != (quals2 < 0))
16174 /* Only of the args is a reference, see if we should apply
16175 array/function pointer decay to it. This is not part of
16176 DR214, but is, IMHO, consistent with the deduction rules
16177 for the function call itself, and with our earlier
16178 implementation of the underspecified partial ordering
16179 rules. (nathan). */
16182 switch (TREE_CODE (arg1))
16185 arg1 = TREE_TYPE (arg1);
16187 case FUNCTION_TYPE:
16188 arg1 = build_pointer_type (arg1);
16197 switch (TREE_CODE (arg2))
16200 arg2 = TREE_TYPE (arg2);
16202 case FUNCTION_TYPE:
16203 arg2 = build_pointer_type (arg2);
16212 arg1 = TYPE_MAIN_VARIANT (arg1);
16213 arg2 = TYPE_MAIN_VARIANT (arg2);
16215 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16217 int i, len2 = list_length (args2);
16218 tree parmvec = make_tree_vec (1);
16219 tree argvec = make_tree_vec (len2);
16222 /* Setup the parameter vector, which contains only ARG1. */
16223 TREE_VEC_ELT (parmvec, 0) = arg1;
16225 /* Setup the argument vector, which contains the remaining
16227 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16228 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16230 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
16231 argvec, UNIFY_ALLOW_NONE,
16232 /*call_args_p=*/false,
16235 /* We cannot deduce in the other direction, because ARG1 is
16236 a pack expansion but ARG2 is not. */
16239 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16241 int i, len1 = list_length (args1);
16242 tree parmvec = make_tree_vec (1);
16243 tree argvec = make_tree_vec (len1);
16246 /* Setup the parameter vector, which contains only ARG1. */
16247 TREE_VEC_ELT (parmvec, 0) = arg2;
16249 /* Setup the argument vector, which contains the remaining
16251 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16252 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16254 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
16255 argvec, UNIFY_ALLOW_NONE,
16256 /*call_args_p=*/false,
16259 /* We cannot deduce in the other direction, because ARG2 is
16260 a pack expansion but ARG1 is not.*/
16266 /* The normal case, where neither argument is a pack
16268 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
16269 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
16272 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16273 arg2, then arg2 is not as specialized as arg1. */
16279 /* "If, for a given type, deduction succeeds in both directions
16280 (i.e., the types are identical after the transformations above)
16281 and if the type from the argument template is more cv-qualified
16282 than the type from the parameter template (as described above)
16283 that type is considered to be more specialized than the other. If
16284 neither type is more cv-qualified than the other then neither type
16285 is more specialized than the other." */
16287 if (deduce1 && deduce2
16288 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16290 if ((quals1 & quals2) == quals2)
16292 if ((quals1 & quals2) == quals1)
16296 if (lose1 && lose2)
16297 /* We've failed to deduce something in either direction.
16298 These must be unordered. */
16301 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16302 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16303 /* We have already processed all of the arguments in our
16304 handing of the pack expansion type. */
16307 args1 = TREE_CHAIN (args1);
16308 args2 = TREE_CHAIN (args2);
16311 /* "In most cases, all template parameters must have values in order for
16312 deduction to succeed, but for partial ordering purposes a template
16313 parameter may remain without a value provided it is not used in the
16314 types being used for partial ordering."
16316 Thus, if we are missing any of the targs1 we need to substitute into
16317 origs1, then pat2 is not as specialized as pat1. This can happen when
16318 there is a nondeduced context. */
16319 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16321 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16324 processing_template_decl--;
16326 /* All things being equal, if the next argument is a pack expansion
16327 for one function but not for the other, prefer the
16328 non-variadic function. FIXME this is bogus; see c++/41958. */
16330 && args1 && TREE_VALUE (args1)
16331 && args2 && TREE_VALUE (args2))
16333 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16334 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16337 if (lose1 == lose2)
16345 /* Determine which of two partial specializations is more specialized.
16347 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16348 to the first partial specialization. The TREE_VALUE is the
16349 innermost set of template parameters for the partial
16350 specialization. PAT2 is similar, but for the second template.
16352 Return 1 if the first partial specialization is more specialized;
16353 -1 if the second is more specialized; 0 if neither is more
16356 See [temp.class.order] for information about determining which of
16357 two templates is more specialized. */
16360 more_specialized_class (tree pat1, tree pat2)
16365 bool any_deductions = false;
16367 tmpl1 = TREE_TYPE (pat1);
16368 tmpl2 = TREE_TYPE (pat2);
16370 /* Just like what happens for functions, if we are ordering between
16371 different class template specializations, we may encounter dependent
16372 types in the arguments, and we need our dependency check functions
16373 to behave correctly. */
16374 ++processing_template_decl;
16375 targs = get_class_bindings (TREE_VALUE (pat1),
16376 CLASSTYPE_TI_ARGS (tmpl1),
16377 CLASSTYPE_TI_ARGS (tmpl2));
16381 any_deductions = true;
16384 targs = get_class_bindings (TREE_VALUE (pat2),
16385 CLASSTYPE_TI_ARGS (tmpl2),
16386 CLASSTYPE_TI_ARGS (tmpl1));
16390 any_deductions = true;
16392 --processing_template_decl;
16394 /* In the case of a tie where at least one of the class templates
16395 has a parameter pack at the end, the template with the most
16396 non-packed parameters wins. */
16399 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16400 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16402 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16403 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16404 int len1 = TREE_VEC_LENGTH (args1);
16405 int len2 = TREE_VEC_LENGTH (args2);
16407 /* We don't count the pack expansion at the end. */
16408 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16410 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16415 else if (len1 < len2)
16422 /* Return the template arguments that will produce the function signature
16423 DECL from the function template FN, with the explicit template
16424 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16425 also match. Return NULL_TREE if no satisfactory arguments could be
16429 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16431 int ntparms = DECL_NTPARMS (fn);
16432 tree targs = make_tree_vec (ntparms);
16434 tree decl_arg_types;
16436 unsigned int nargs, ix;
16439 /* Substitute the explicit template arguments into the type of DECL.
16440 The call to fn_type_unification will handle substitution into the
16442 decl_type = TREE_TYPE (decl);
16443 if (explicit_args && uses_template_parms (decl_type))
16446 tree converted_args;
16448 if (DECL_TEMPLATE_INFO (decl))
16449 tmpl = DECL_TI_TEMPLATE (decl);
16451 /* We can get here for some invalid specializations. */
16455 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16456 explicit_args, NULL_TREE,
16458 /*require_all_args=*/false,
16459 /*use_default_args=*/false);
16460 if (converted_args == error_mark_node)
16463 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16464 if (decl_type == error_mark_node)
16468 /* Never do unification on the 'this' parameter. */
16469 decl_arg_types = skip_artificial_parms_for (decl,
16470 TYPE_ARG_TYPES (decl_type));
16472 nargs = list_length (decl_arg_types);
16473 args = XALLOCAVEC (tree, nargs);
16474 for (arg = decl_arg_types, ix = 0;
16475 arg != NULL_TREE && arg != void_list_node;
16476 arg = TREE_CHAIN (arg), ++ix)
16477 args[ix] = TREE_VALUE (arg);
16479 if (fn_type_unification (fn, explicit_args, targs,
16481 (check_rettype || DECL_CONV_FN_P (fn)
16482 ? TREE_TYPE (decl_type) : NULL_TREE),
16483 DEDUCE_EXACT, LOOKUP_NORMAL))
16489 /* Return the innermost template arguments that, when applied to a
16490 template specialization whose innermost template parameters are
16491 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
16494 For example, suppose we have:
16496 template <class T, class U> struct S {};
16497 template <class T> struct S<T*, int> {};
16499 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
16500 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
16501 int}. The resulting vector will be {double}, indicating that `T'
16502 is bound to `double'. */
16505 get_class_bindings (tree tparms, tree spec_args, tree args)
16507 int i, ntparms = TREE_VEC_LENGTH (tparms);
16509 tree innermost_deduced_args;
16511 innermost_deduced_args = make_tree_vec (ntparms);
16512 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16514 deduced_args = copy_node (args);
16515 SET_TMPL_ARGS_LEVEL (deduced_args,
16516 TMPL_ARGS_DEPTH (deduced_args),
16517 innermost_deduced_args);
16520 deduced_args = innermost_deduced_args;
16522 if (unify (tparms, deduced_args,
16523 INNERMOST_TEMPLATE_ARGS (spec_args),
16524 INNERMOST_TEMPLATE_ARGS (args),
16528 for (i = 0; i < ntparms; ++i)
16529 if (! TREE_VEC_ELT (innermost_deduced_args, i))
16532 /* Verify that nondeduced template arguments agree with the type
16533 obtained from argument deduction.
16537 struct A { typedef int X; };
16538 template <class T, class U> struct C {};
16539 template <class T> struct C<T, typename T::X> {};
16541 Then with the instantiation `C<A, int>', we can deduce that
16542 `T' is `A' but unify () does not check whether `typename T::X'
16544 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
16545 if (spec_args == error_mark_node
16546 /* We only need to check the innermost arguments; the other
16547 arguments will always agree. */
16548 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
16549 INNERMOST_TEMPLATE_ARGS (args)))
16552 /* Now that we have bindings for all of the template arguments,
16553 ensure that the arguments deduced for the template template
16554 parameters have compatible template parameter lists. See the use
16555 of template_template_parm_bindings_ok_p in fn_type_unification
16556 for more information. */
16557 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
16560 return deduced_args;
16563 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
16564 Return the TREE_LIST node with the most specialized template, if
16565 any. If there is no most specialized template, the error_mark_node
16568 Note that this function does not look at, or modify, the
16569 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
16570 returned is one of the elements of INSTANTIATIONS, callers may
16571 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
16572 and retrieve it from the value returned. */
16575 most_specialized_instantiation (tree templates)
16579 ++processing_template_decl;
16582 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
16586 if (get_bindings (TREE_VALUE (champ),
16587 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16588 NULL_TREE, /*check_ret=*/false))
16591 if (get_bindings (TREE_VALUE (fn),
16592 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16593 NULL_TREE, /*check_ret=*/false))
16600 /* Equally specialized, move to next function. If there
16601 is no next function, nothing's most specialized. */
16602 fn = TREE_CHAIN (fn);
16610 /* Now verify that champ is better than everything earlier in the
16611 instantiation list. */
16612 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
16613 if (get_bindings (TREE_VALUE (champ),
16614 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16615 NULL_TREE, /*check_ret=*/false)
16616 || !get_bindings (TREE_VALUE (fn),
16617 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16618 NULL_TREE, /*check_ret=*/false))
16624 processing_template_decl--;
16627 return error_mark_node;
16632 /* If DECL is a specialization of some template, return the most
16633 general such template. Otherwise, returns NULL_TREE.
16635 For example, given:
16637 template <class T> struct S { template <class U> void f(U); };
16639 if TMPL is `template <class U> void S<int>::f(U)' this will return
16640 the full template. This function will not trace past partial
16641 specializations, however. For example, given in addition:
16643 template <class T> struct S<T*> { template <class U> void f(U); };
16645 if TMPL is `template <class U> void S<int*>::f(U)' this will return
16646 `template <class T> template <class U> S<T*>::f(U)'. */
16649 most_general_template (tree decl)
16651 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
16652 an immediate specialization. */
16653 if (TREE_CODE (decl) == FUNCTION_DECL)
16655 if (DECL_TEMPLATE_INFO (decl)) {
16656 decl = DECL_TI_TEMPLATE (decl);
16658 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
16659 template friend. */
16660 if (TREE_CODE (decl) != TEMPLATE_DECL)
16666 /* Look for more and more general templates. */
16667 while (DECL_TEMPLATE_INFO (decl))
16669 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
16670 (See cp-tree.h for details.) */
16671 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
16674 if (CLASS_TYPE_P (TREE_TYPE (decl))
16675 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
16678 /* Stop if we run into an explicitly specialized class template. */
16679 if (!DECL_NAMESPACE_SCOPE_P (decl)
16680 && DECL_CONTEXT (decl)
16681 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16684 decl = DECL_TI_TEMPLATE (decl);
16690 /* Return the most specialized of the class template partial
16691 specializations of TMPL which can produce TYPE, a specialization of
16692 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16693 a _TYPE node corresponding to the partial specialization, while the
16694 TREE_PURPOSE is the set of template arguments that must be
16695 substituted into the TREE_TYPE in order to generate TYPE.
16697 If the choice of partial specialization is ambiguous, a diagnostic
16698 is issued, and the error_mark_node is returned. If there are no
16699 partial specializations of TMPL matching TYPE, then NULL_TREE is
16703 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16705 tree list = NULL_TREE;
16711 tree outer_args = NULL_TREE;
16713 tmpl = most_general_template (tmpl);
16714 args = CLASSTYPE_TI_ARGS (type);
16716 /* For determining which partial specialization to use, only the
16717 innermost args are interesting. */
16718 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16720 outer_args = strip_innermost_template_args (args, 1);
16721 args = INNERMOST_TEMPLATE_ARGS (args);
16724 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16726 tree partial_spec_args;
16728 tree parms = TREE_VALUE (t);
16730 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16732 ++processing_template_decl;
16738 /* Discard the outer levels of args, and then substitute in the
16739 template args from the enclosing class. */
16740 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16741 partial_spec_args = tsubst_template_args
16742 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16744 /* PARMS already refers to just the innermost parms, but the
16745 template parms in partial_spec_args had their levels lowered
16746 by tsubst, so we need to do the same for the parm list. We
16747 can't just tsubst the TREE_VEC itself, as tsubst wants to
16748 treat a TREE_VEC as an argument vector. */
16749 parms = copy_node (parms);
16750 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16751 TREE_VEC_ELT (parms, i) =
16752 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16756 partial_spec_args =
16757 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16758 add_to_template_args (outer_args,
16759 partial_spec_args),
16761 /*require_all_args=*/true,
16762 /*use_default_args=*/true);
16764 --processing_template_decl;
16766 if (partial_spec_args == error_mark_node)
16767 return error_mark_node;
16769 spec_args = get_class_bindings (parms,
16775 spec_args = add_to_template_args (outer_args, spec_args);
16776 list = tree_cons (spec_args, TREE_VALUE (t), list);
16777 TREE_TYPE (list) = TREE_TYPE (t);
16784 ambiguous_p = false;
16787 t = TREE_CHAIN (t);
16788 for (; t; t = TREE_CHAIN (t))
16790 fate = more_specialized_class (champ, t);
16797 t = TREE_CHAIN (t);
16800 ambiguous_p = true;
16809 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16811 fate = more_specialized_class (champ, t);
16814 ambiguous_p = true;
16822 char *spaces = NULL;
16823 if (!(complain & tf_error))
16824 return error_mark_node;
16825 error ("ambiguous class template instantiation for %q#T", type);
16826 str = ngettext ("candidate is:", "candidates are:", list_length (list));
16827 for (t = list; t; t = TREE_CHAIN (t))
16829 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16830 spaces = spaces ? spaces : get_spaces (str);
16833 return error_mark_node;
16839 /* Explicitly instantiate DECL. */
16842 do_decl_instantiation (tree decl, tree storage)
16844 tree result = NULL_TREE;
16847 if (!decl || decl == error_mark_node)
16848 /* An error occurred, for which grokdeclarator has already issued
16849 an appropriate message. */
16851 else if (! DECL_LANG_SPECIFIC (decl))
16853 error ("explicit instantiation of non-template %q#D", decl);
16856 else if (TREE_CODE (decl) == VAR_DECL)
16858 /* There is an asymmetry here in the way VAR_DECLs and
16859 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16860 the latter, the DECL we get back will be marked as a
16861 template instantiation, and the appropriate
16862 DECL_TEMPLATE_INFO will be set up. This does not happen for
16863 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16864 should handle VAR_DECLs as it currently handles
16866 if (!DECL_CLASS_SCOPE_P (decl))
16868 error ("%qD is not a static data member of a class template", decl);
16871 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16872 if (!result || TREE_CODE (result) != VAR_DECL)
16874 error ("no matching template for %qD found", decl);
16877 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16879 error ("type %qT for explicit instantiation %qD does not match "
16880 "declared type %qT", TREE_TYPE (result), decl,
16885 else if (TREE_CODE (decl) != FUNCTION_DECL)
16887 error ("explicit instantiation of %q#D", decl);
16893 /* Check for various error cases. Note that if the explicit
16894 instantiation is valid the RESULT will currently be marked as an
16895 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16896 until we get here. */
16898 if (DECL_TEMPLATE_SPECIALIZATION (result))
16900 /* DR 259 [temp.spec].
16902 Both an explicit instantiation and a declaration of an explicit
16903 specialization shall not appear in a program unless the explicit
16904 instantiation follows a declaration of the explicit specialization.
16906 For a given set of template parameters, if an explicit
16907 instantiation of a template appears after a declaration of an
16908 explicit specialization for that template, the explicit
16909 instantiation has no effect. */
16912 else if (DECL_EXPLICIT_INSTANTIATION (result))
16916 No program shall explicitly instantiate any template more
16919 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16920 the first instantiation was `extern' and the second is not,
16921 and EXTERN_P for the opposite case. */
16922 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16923 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16924 /* If an "extern" explicit instantiation follows an ordinary
16925 explicit instantiation, the template is instantiated. */
16929 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16931 error ("no matching template for %qD found", result);
16934 else if (!DECL_TEMPLATE_INFO (result))
16936 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16940 if (storage == NULL_TREE)
16942 else if (storage == ridpointers[(int) RID_EXTERN])
16944 if (!in_system_header && (cxx_dialect == cxx98))
16945 pedwarn (input_location, OPT_pedantic,
16946 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16951 error ("storage class %qD applied to template instantiation", storage);
16953 check_explicit_instantiation_namespace (result);
16954 mark_decl_instantiated (result, extern_p);
16956 instantiate_decl (result, /*defer_ok=*/1,
16957 /*expl_inst_class_mem_p=*/false);
16961 mark_class_instantiated (tree t, int extern_p)
16963 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16964 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16965 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16966 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16969 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16970 rest_of_type_compilation (t, 1);
16974 /* Called from do_type_instantiation through binding_table_foreach to
16975 do recursive instantiation for the type bound in ENTRY. */
16977 bt_instantiate_type_proc (binding_entry entry, void *data)
16979 tree storage = *(tree *) data;
16981 if (MAYBE_CLASS_TYPE_P (entry->type)
16982 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16983 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16986 /* Called from do_type_instantiation to instantiate a member
16987 (a member function or a static member variable) of an
16988 explicitly instantiated class template. */
16990 instantiate_class_member (tree decl, int extern_p)
16992 mark_decl_instantiated (decl, extern_p);
16994 instantiate_decl (decl, /*defer_ok=*/1,
16995 /*expl_inst_class_mem_p=*/true);
16998 /* Perform an explicit instantiation of template class T. STORAGE, if
16999 non-null, is the RID for extern, inline or static. COMPLAIN is
17000 nonzero if this is called from the parser, zero if called recursively,
17001 since the standard is unclear (as detailed below). */
17004 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17009 int previous_instantiation_extern_p = 0;
17011 if (TREE_CODE (t) == TYPE_DECL)
17014 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17016 error ("explicit instantiation of non-template type %qT", t);
17022 if (!COMPLETE_TYPE_P (t))
17024 if (complain & tf_error)
17025 error ("explicit instantiation of %q#T before definition of template",
17030 if (storage != NULL_TREE)
17032 if (!in_system_header)
17034 if (storage == ridpointers[(int) RID_EXTERN])
17036 if (cxx_dialect == cxx98)
17037 pedwarn (input_location, OPT_pedantic,
17038 "ISO C++ 1998 forbids the use of %<extern%> on "
17039 "explicit instantiations");
17042 pedwarn (input_location, OPT_pedantic,
17043 "ISO C++ forbids the use of %qE"
17044 " on explicit instantiations", storage);
17047 if (storage == ridpointers[(int) RID_INLINE])
17049 else if (storage == ridpointers[(int) RID_EXTERN])
17051 else if (storage == ridpointers[(int) RID_STATIC])
17055 error ("storage class %qD applied to template instantiation",
17061 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17063 /* DR 259 [temp.spec].
17065 Both an explicit instantiation and a declaration of an explicit
17066 specialization shall not appear in a program unless the explicit
17067 instantiation follows a declaration of the explicit specialization.
17069 For a given set of template parameters, if an explicit
17070 instantiation of a template appears after a declaration of an
17071 explicit specialization for that template, the explicit
17072 instantiation has no effect. */
17075 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17079 No program shall explicitly instantiate any template more
17082 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17083 instantiation was `extern'. If EXTERN_P then the second is.
17084 These cases are OK. */
17085 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17087 if (!previous_instantiation_extern_p && !extern_p
17088 && (complain & tf_error))
17089 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17091 /* If we've already instantiated the template, just return now. */
17092 if (!CLASSTYPE_INTERFACE_ONLY (t))
17096 check_explicit_instantiation_namespace (TYPE_NAME (t));
17097 mark_class_instantiated (t, extern_p);
17105 /* In contrast to implicit instantiation, where only the
17106 declarations, and not the definitions, of members are
17107 instantiated, we have here:
17111 The explicit instantiation of a class template specialization
17112 implies the instantiation of all of its members not
17113 previously explicitly specialized in the translation unit
17114 containing the explicit instantiation.
17116 Of course, we can't instantiate member template classes, since
17117 we don't have any arguments for them. Note that the standard
17118 is unclear on whether the instantiation of the members are
17119 *explicit* instantiations or not. However, the most natural
17120 interpretation is that it should be an explicit instantiation. */
17123 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17124 if (TREE_CODE (tmp) == FUNCTION_DECL
17125 && DECL_TEMPLATE_INSTANTIATION (tmp))
17126 instantiate_class_member (tmp, extern_p);
17128 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17129 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17130 instantiate_class_member (tmp, extern_p);
17132 if (CLASSTYPE_NESTED_UTDS (t))
17133 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17134 bt_instantiate_type_proc, &storage);
17138 /* Given a function DECL, which is a specialization of TMPL, modify
17139 DECL to be a re-instantiation of TMPL with the same template
17140 arguments. TMPL should be the template into which tsubst'ing
17141 should occur for DECL, not the most general template.
17143 One reason for doing this is a scenario like this:
17146 void f(const T&, int i);
17148 void g() { f(3, 7); }
17151 void f(const T& t, const int i) { }
17153 Note that when the template is first instantiated, with
17154 instantiate_template, the resulting DECL will have no name for the
17155 first parameter, and the wrong type for the second. So, when we go
17156 to instantiate the DECL, we regenerate it. */
17159 regenerate_decl_from_template (tree decl, tree tmpl)
17161 /* The arguments used to instantiate DECL, from the most general
17166 args = DECL_TI_ARGS (decl);
17167 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17169 /* Make sure that we can see identifiers, and compute access
17171 push_access_scope (decl);
17173 if (TREE_CODE (decl) == FUNCTION_DECL)
17181 args_depth = TMPL_ARGS_DEPTH (args);
17182 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17183 if (args_depth > parms_depth)
17184 args = get_innermost_template_args (args, parms_depth);
17186 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17187 args, tf_error, NULL_TREE,
17188 /*defer_ok*/false);
17190 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17193 /* Merge parameter declarations. */
17194 decl_parm = skip_artificial_parms_for (decl,
17195 DECL_ARGUMENTS (decl));
17197 = skip_artificial_parms_for (code_pattern,
17198 DECL_ARGUMENTS (code_pattern));
17199 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17204 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17205 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17206 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17208 parm_type = type_decays_to (parm_type);
17209 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17210 TREE_TYPE (decl_parm) = parm_type;
17211 attributes = DECL_ATTRIBUTES (pattern_parm);
17212 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17214 DECL_ATTRIBUTES (decl_parm) = attributes;
17215 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17217 decl_parm = DECL_CHAIN (decl_parm);
17218 pattern_parm = DECL_CHAIN (pattern_parm);
17220 /* Merge any parameters that match with the function parameter
17222 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17225 tree expanded_types;
17226 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17227 the parameters in this function parameter pack. */
17228 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17229 args, tf_error, NULL_TREE);
17230 len = TREE_VEC_LENGTH (expanded_types);
17231 for (i = 0; i < len; i++)
17236 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17237 /* Rename the parameter to include the index. */
17238 DECL_NAME (decl_parm) =
17239 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17240 parm_type = TREE_VEC_ELT (expanded_types, i);
17241 parm_type = type_decays_to (parm_type);
17242 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17243 TREE_TYPE (decl_parm) = parm_type;
17244 attributes = DECL_ATTRIBUTES (pattern_parm);
17245 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17247 DECL_ATTRIBUTES (decl_parm) = attributes;
17248 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17250 decl_parm = DECL_CHAIN (decl_parm);
17253 /* Merge additional specifiers from the CODE_PATTERN. */
17254 if (DECL_DECLARED_INLINE_P (code_pattern)
17255 && !DECL_DECLARED_INLINE_P (decl))
17256 DECL_DECLARED_INLINE_P (decl) = 1;
17258 else if (TREE_CODE (decl) == VAR_DECL)
17260 DECL_INITIAL (decl) =
17261 tsubst_expr (DECL_INITIAL (code_pattern), args,
17262 tf_error, DECL_TI_TEMPLATE (decl),
17263 /*integral_constant_expression_p=*/false);
17264 if (VAR_HAD_UNKNOWN_BOUND (decl))
17265 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17266 tf_error, DECL_TI_TEMPLATE (decl));
17269 gcc_unreachable ();
17271 pop_access_scope (decl);
17274 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17275 substituted to get DECL. */
17278 template_for_substitution (tree decl)
17280 tree tmpl = DECL_TI_TEMPLATE (decl);
17282 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17283 for the instantiation. This is not always the most general
17284 template. Consider, for example:
17287 struct S { template <class U> void f();
17288 template <> void f<int>(); };
17290 and an instantiation of S<double>::f<int>. We want TD to be the
17291 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17292 while (/* An instantiation cannot have a definition, so we need a
17293 more general template. */
17294 DECL_TEMPLATE_INSTANTIATION (tmpl)
17295 /* We must also deal with friend templates. Given:
17297 template <class T> struct S {
17298 template <class U> friend void f() {};
17301 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17302 so far as the language is concerned, but that's still
17303 where we get the pattern for the instantiation from. On
17304 other hand, if the definition comes outside the class, say:
17306 template <class T> struct S {
17307 template <class U> friend void f();
17309 template <class U> friend void f() {}
17311 we don't need to look any further. That's what the check for
17312 DECL_INITIAL is for. */
17313 || (TREE_CODE (decl) == FUNCTION_DECL
17314 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17315 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17317 /* The present template, TD, should not be a definition. If it
17318 were a definition, we should be using it! Note that we
17319 cannot restructure the loop to just keep going until we find
17320 a template with a definition, since that might go too far if
17321 a specialization was declared, but not defined. */
17322 gcc_assert (TREE_CODE (decl) != VAR_DECL
17323 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17325 /* Fetch the more general template. */
17326 tmpl = DECL_TI_TEMPLATE (tmpl);
17332 /* Returns true if we need to instantiate this template instance even if we
17333 know we aren't going to emit it.. */
17336 always_instantiate_p (tree decl)
17338 /* We always instantiate inline functions so that we can inline them. An
17339 explicit instantiation declaration prohibits implicit instantiation of
17340 non-inline functions. With high levels of optimization, we would
17341 normally inline non-inline functions -- but we're not allowed to do
17342 that for "extern template" functions. Therefore, we check
17343 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17344 return ((TREE_CODE (decl) == FUNCTION_DECL
17345 && DECL_DECLARED_INLINE_P (decl))
17346 /* And we need to instantiate static data members so that
17347 their initializers are available in integral constant
17349 || (TREE_CODE (decl) == VAR_DECL
17350 && decl_maybe_constant_var_p (decl)));
17353 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
17354 instantiate it now, modifying TREE_TYPE (fn). */
17357 maybe_instantiate_noexcept (tree fn)
17359 tree fntype, spec, noex, clone;
17361 if (DECL_CLONED_FUNCTION_P (fn))
17362 fn = DECL_CLONED_FUNCTION (fn);
17363 fntype = TREE_TYPE (fn);
17364 spec = TYPE_RAISES_EXCEPTIONS (fntype);
17366 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
17369 noex = TREE_PURPOSE (spec);
17371 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
17373 push_tinst_level (fn);
17374 push_access_scope (fn);
17375 input_location = DECL_SOURCE_LOCATION (fn);
17376 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
17377 DEFERRED_NOEXCEPT_ARGS (noex),
17378 tf_warning_or_error, fn, /*function_p=*/false,
17379 /*integral_constant_expression_p=*/true);
17380 pop_access_scope (fn);
17381 pop_tinst_level ();
17382 spec = build_noexcept_spec (noex, tf_warning_or_error);
17383 if (spec == error_mark_node)
17384 spec = noexcept_false_spec;
17388 /* This is an implicitly declared function, so NOEX is a list of
17389 other functions to evaluate and merge. */
17391 spec = noexcept_true_spec;
17392 for (elt = noex; elt; elt = OVL_NEXT (elt))
17394 tree fn = OVL_CURRENT (elt);
17396 maybe_instantiate_noexcept (fn);
17397 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
17398 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
17402 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
17404 FOR_EACH_CLONE (clone, fn)
17406 if (TREE_TYPE (clone) == fntype)
17407 TREE_TYPE (clone) = TREE_TYPE (fn);
17409 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
17413 /* Produce the definition of D, a _DECL generated from a template. If
17414 DEFER_OK is nonzero, then we don't have to actually do the
17415 instantiation now; we just have to do it sometime. Normally it is
17416 an error if this is an explicit instantiation but D is undefined.
17417 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17418 explicitly instantiated class template. */
17421 instantiate_decl (tree d, int defer_ok,
17422 bool expl_inst_class_mem_p)
17424 tree tmpl = DECL_TI_TEMPLATE (d);
17431 bool pattern_defined;
17433 location_t saved_loc = input_location;
17436 /* This function should only be used to instantiate templates for
17437 functions and static member variables. */
17438 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17439 || TREE_CODE (d) == VAR_DECL);
17441 /* Variables are never deferred; if instantiation is required, they
17442 are instantiated right away. That allows for better code in the
17443 case that an expression refers to the value of the variable --
17444 if the variable has a constant value the referring expression can
17445 take advantage of that fact. */
17446 if (TREE_CODE (d) == VAR_DECL
17447 || DECL_DECLARED_CONSTEXPR_P (d))
17450 /* Don't instantiate cloned functions. Instead, instantiate the
17451 functions they cloned. */
17452 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17453 d = DECL_CLONED_FUNCTION (d);
17455 if (DECL_TEMPLATE_INSTANTIATED (d)
17456 || DECL_TEMPLATE_SPECIALIZATION (d))
17457 /* D has already been instantiated or explicitly specialized, so
17458 there's nothing for us to do here.
17460 It might seem reasonable to check whether or not D is an explicit
17461 instantiation, and, if so, stop here. But when an explicit
17462 instantiation is deferred until the end of the compilation,
17463 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17464 the instantiation. */
17467 /* Check to see whether we know that this template will be
17468 instantiated in some other file, as with "extern template"
17470 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17472 /* In general, we do not instantiate such templates. */
17473 if (external_p && !always_instantiate_p (d))
17476 gen_tmpl = most_general_template (tmpl);
17477 gen_args = DECL_TI_ARGS (d);
17479 if (tmpl != gen_tmpl)
17480 /* We should already have the extra args. */
17481 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17482 == TMPL_ARGS_DEPTH (gen_args));
17483 /* And what's in the hash table should match D. */
17484 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17485 || spec == NULL_TREE);
17487 /* This needs to happen before any tsubsting. */
17488 if (! push_tinst_level (d))
17491 timevar_push (TV_TEMPLATE_INST);
17493 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
17494 for the instantiation. */
17495 td = template_for_substitution (d);
17496 code_pattern = DECL_TEMPLATE_RESULT (td);
17498 /* We should never be trying to instantiate a member of a class
17499 template or partial specialization. */
17500 gcc_assert (d != code_pattern);
17502 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
17503 || DECL_TEMPLATE_SPECIALIZATION (td))
17504 /* In the case of a friend template whose definition is provided
17505 outside the class, we may have too many arguments. Drop the
17506 ones we don't need. The same is true for specializations. */
17507 args = get_innermost_template_args
17508 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
17512 if (TREE_CODE (d) == FUNCTION_DECL)
17513 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
17514 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
17516 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
17518 /* We may be in the middle of deferred access check. Disable it now. */
17519 push_deferring_access_checks (dk_no_deferred);
17521 /* Unless an explicit instantiation directive has already determined
17522 the linkage of D, remember that a definition is available for
17524 if (pattern_defined
17525 && !DECL_INTERFACE_KNOWN (d)
17526 && !DECL_NOT_REALLY_EXTERN (d))
17527 mark_definable (d);
17529 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
17530 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
17531 input_location = DECL_SOURCE_LOCATION (d);
17533 /* If D is a member of an explicitly instantiated class template,
17534 and no definition is available, treat it like an implicit
17536 if (!pattern_defined && expl_inst_class_mem_p
17537 && DECL_EXPLICIT_INSTANTIATION (d))
17539 /* Leave linkage flags alone on instantiations with anonymous
17541 if (TREE_PUBLIC (d))
17543 DECL_NOT_REALLY_EXTERN (d) = 0;
17544 DECL_INTERFACE_KNOWN (d) = 0;
17546 SET_DECL_IMPLICIT_INSTANTIATION (d);
17549 if (TREE_CODE (d) == FUNCTION_DECL)
17550 maybe_instantiate_noexcept (d);
17552 /* Recheck the substitutions to obtain any warning messages
17553 about ignoring cv qualifiers. Don't do this for artificial decls,
17554 as it breaks the context-sensitive substitution for lambda op(). */
17555 if (!defer_ok && !DECL_ARTIFICIAL (d))
17557 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
17558 tree type = TREE_TYPE (gen);
17560 /* Make sure that we can see identifiers, and compute access
17561 correctly. D is already the target FUNCTION_DECL with the
17563 push_access_scope (d);
17565 if (TREE_CODE (gen) == FUNCTION_DECL)
17567 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
17568 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
17569 d, /*defer_ok*/true);
17570 /* Don't simply tsubst the function type, as that will give
17571 duplicate warnings about poor parameter qualifications.
17572 The function arguments are the same as the decl_arguments
17573 without the top level cv qualifiers. */
17574 type = TREE_TYPE (type);
17576 tsubst (type, gen_args, tf_warning_or_error, d);
17578 pop_access_scope (d);
17581 /* Defer all other templates, unless we have been explicitly
17582 forbidden from doing so. */
17583 if (/* If there is no definition, we cannot instantiate the
17586 /* If it's OK to postpone instantiation, do so. */
17588 /* If this is a static data member that will be defined
17589 elsewhere, we don't want to instantiate the entire data
17590 member, but we do want to instantiate the initializer so that
17591 we can substitute that elsewhere. */
17592 || (external_p && TREE_CODE (d) == VAR_DECL))
17594 /* The definition of the static data member is now required so
17595 we must substitute the initializer. */
17596 if (TREE_CODE (d) == VAR_DECL
17597 && !DECL_INITIAL (d)
17598 && DECL_INITIAL (code_pattern))
17602 bool const_init = false;
17604 ns = decl_namespace_context (d);
17605 push_nested_namespace (ns);
17606 push_nested_class (DECL_CONTEXT (d));
17607 init = tsubst_expr (DECL_INITIAL (code_pattern),
17609 tf_warning_or_error, NULL_TREE,
17610 /*integral_constant_expression_p=*/false);
17611 /* Make sure the initializer is still constant, in case of
17612 circular dependency (template/instantiate6.C). */
17614 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17615 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
17616 /*asmspec_tree=*/NULL_TREE,
17617 LOOKUP_ONLYCONVERTING);
17618 pop_nested_class ();
17619 pop_nested_namespace (ns);
17622 /* We restore the source position here because it's used by
17623 add_pending_template. */
17624 input_location = saved_loc;
17626 if (at_eof && !pattern_defined
17627 && DECL_EXPLICIT_INSTANTIATION (d)
17628 && DECL_NOT_REALLY_EXTERN (d))
17631 The definition of a non-exported function template, a
17632 non-exported member function template, or a non-exported
17633 member function or static data member of a class template
17634 shall be present in every translation unit in which it is
17635 explicitly instantiated. */
17636 permerror (input_location, "explicit instantiation of %qD "
17637 "but no definition available", d);
17639 /* If we're in unevaluated context, we just wanted to get the
17640 constant value; this isn't an odr use, so don't queue
17641 a full instantiation. */
17642 if (cp_unevaluated_operand != 0)
17644 /* ??? Historically, we have instantiated inline functions, even
17645 when marked as "extern template". */
17646 if (!(external_p && TREE_CODE (d) == VAR_DECL))
17647 add_pending_template (d);
17650 /* Tell the repository that D is available in this translation unit
17651 -- and see if it is supposed to be instantiated here. */
17652 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
17654 /* In a PCH file, despite the fact that the repository hasn't
17655 requested instantiation in the PCH it is still possible that
17656 an instantiation will be required in a file that includes the
17659 add_pending_template (d);
17660 /* Instantiate inline functions so that the inliner can do its
17661 job, even though we'll not be emitting a copy of this
17663 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
17667 need_push = !cfun || !global_bindings_p ();
17669 push_to_top_level ();
17671 /* Mark D as instantiated so that recursive calls to
17672 instantiate_decl do not try to instantiate it again. */
17673 DECL_TEMPLATE_INSTANTIATED (d) = 1;
17675 /* Regenerate the declaration in case the template has been modified
17676 by a subsequent redeclaration. */
17677 regenerate_decl_from_template (d, td);
17679 /* We already set the file and line above. Reset them now in case
17680 they changed as a result of calling regenerate_decl_from_template. */
17681 input_location = DECL_SOURCE_LOCATION (d);
17683 if (TREE_CODE (d) == VAR_DECL)
17686 bool const_init = false;
17688 /* Clear out DECL_RTL; whatever was there before may not be right
17689 since we've reset the type of the declaration. */
17690 SET_DECL_RTL (d, NULL);
17691 DECL_IN_AGGR_P (d) = 0;
17693 /* The initializer is placed in DECL_INITIAL by
17694 regenerate_decl_from_template so we don't need to
17695 push/pop_access_scope again here. Pull it out so that
17696 cp_finish_decl can process it. */
17697 init = DECL_INITIAL (d);
17698 DECL_INITIAL (d) = NULL_TREE;
17699 DECL_INITIALIZED_P (d) = 0;
17701 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
17702 initializer. That function will defer actual emission until
17703 we have a chance to determine linkage. */
17704 DECL_EXTERNAL (d) = 0;
17706 /* Enter the scope of D so that access-checking works correctly. */
17707 push_nested_class (DECL_CONTEXT (d));
17708 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17709 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
17710 pop_nested_class ();
17712 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
17713 synthesize_method (d);
17714 else if (TREE_CODE (d) == FUNCTION_DECL)
17716 htab_t saved_local_specializations;
17721 /* Save away the current list, in case we are instantiating one
17722 template from within the body of another. */
17723 saved_local_specializations = local_specializations;
17725 /* Set up the list of local specializations. */
17726 local_specializations = htab_create (37,
17727 hash_local_specialization,
17728 eq_local_specializations,
17731 /* Set up context. */
17732 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
17734 /* Create substitution entries for the parameters. */
17735 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
17736 tmpl_parm = DECL_ARGUMENTS (subst_decl);
17737 spec_parm = DECL_ARGUMENTS (d);
17738 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
17740 register_local_specialization (spec_parm, tmpl_parm);
17741 spec_parm = skip_artificial_parms_for (d, spec_parm);
17742 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
17744 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17746 register_local_specialization (spec_parm, tmpl_parm);
17747 tmpl_parm = DECL_CHAIN (tmpl_parm);
17748 spec_parm = DECL_CHAIN (spec_parm);
17750 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17752 /* Register the (value) argument pack as a specialization of
17753 TMPL_PARM, then move on. */
17754 tree argpack = make_fnparm_pack (spec_parm);
17755 register_local_specialization (argpack, tmpl_parm);
17756 tmpl_parm = DECL_CHAIN (tmpl_parm);
17757 spec_parm = NULL_TREE;
17759 gcc_assert (!spec_parm);
17761 /* Substitute into the body of the function. */
17762 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
17763 tf_warning_or_error, tmpl,
17764 /*integral_constant_expression_p=*/false);
17766 /* Set the current input_location to the end of the function
17767 so that finish_function knows where we are. */
17768 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17770 /* We don't need the local specializations any more. */
17771 htab_delete (local_specializations);
17772 local_specializations = saved_local_specializations;
17774 /* Finish the function. */
17775 d = finish_function (0);
17776 expand_or_defer_fn (d);
17779 /* We're not deferring instantiation any more. */
17780 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17783 pop_from_top_level ();
17786 input_location = saved_loc;
17787 pop_deferring_access_checks ();
17788 pop_tinst_level ();
17790 timevar_pop (TV_TEMPLATE_INST);
17795 /* Run through the list of templates that we wish we could
17796 instantiate, and instantiate any we can. RETRIES is the
17797 number of times we retry pending template instantiation. */
17800 instantiate_pending_templates (int retries)
17803 location_t saved_loc = input_location;
17805 /* Instantiating templates may trigger vtable generation. This in turn
17806 may require further template instantiations. We place a limit here
17807 to avoid infinite loop. */
17808 if (pending_templates && retries >= max_tinst_depth)
17810 tree decl = pending_templates->tinst->decl;
17812 error ("template instantiation depth exceeds maximum of %d"
17813 " instantiating %q+D, possibly from virtual table generation"
17814 " (use -ftemplate-depth= to increase the maximum)",
17815 max_tinst_depth, decl);
17816 if (TREE_CODE (decl) == FUNCTION_DECL)
17817 /* Pretend that we defined it. */
17818 DECL_INITIAL (decl) = error_mark_node;
17824 struct pending_template **t = &pending_templates;
17825 struct pending_template *last = NULL;
17829 tree instantiation = reopen_tinst_level ((*t)->tinst);
17830 bool complete = false;
17832 if (TYPE_P (instantiation))
17836 if (!COMPLETE_TYPE_P (instantiation))
17838 instantiate_class_template (instantiation);
17839 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17840 for (fn = TYPE_METHODS (instantiation);
17842 fn = TREE_CHAIN (fn))
17843 if (! DECL_ARTIFICIAL (fn))
17844 instantiate_decl (fn,
17846 /*expl_inst_class_mem_p=*/false);
17847 if (COMPLETE_TYPE_P (instantiation))
17851 complete = COMPLETE_TYPE_P (instantiation);
17855 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17856 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17859 = instantiate_decl (instantiation,
17861 /*expl_inst_class_mem_p=*/false);
17862 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17866 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17867 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17871 /* If INSTANTIATION has been instantiated, then we don't
17872 need to consider it again in the future. */
17880 current_tinst_level = NULL;
17882 last_pending_template = last;
17884 while (reconsider);
17886 input_location = saved_loc;
17889 /* Substitute ARGVEC into T, which is a list of initializers for
17890 either base class or a non-static data member. The TREE_PURPOSEs
17891 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17892 instantiate_decl. */
17895 tsubst_initializer_list (tree t, tree argvec)
17897 tree inits = NULL_TREE;
17899 for (; t; t = TREE_CHAIN (t))
17903 tree expanded_bases = NULL_TREE;
17904 tree expanded_arguments = NULL_TREE;
17907 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17912 /* Expand the base class expansion type into separate base
17914 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17915 tf_warning_or_error,
17917 if (expanded_bases == error_mark_node)
17920 /* We'll be building separate TREE_LISTs of arguments for
17922 len = TREE_VEC_LENGTH (expanded_bases);
17923 expanded_arguments = make_tree_vec (len);
17924 for (i = 0; i < len; i++)
17925 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17927 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17928 expand each argument in the TREE_VALUE of t. */
17929 expr = make_node (EXPR_PACK_EXPANSION);
17930 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17931 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17933 if (TREE_VALUE (t) == void_type_node)
17934 /* VOID_TYPE_NODE is used to indicate
17935 value-initialization. */
17937 for (i = 0; i < len; i++)
17938 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17942 /* Substitute parameter packs into each argument in the
17944 in_base_initializer = 1;
17945 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17947 tree expanded_exprs;
17949 /* Expand the argument. */
17950 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17952 = tsubst_pack_expansion (expr, argvec,
17953 tf_warning_or_error,
17955 if (expanded_exprs == error_mark_node)
17958 /* Prepend each of the expanded expressions to the
17959 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17960 for (i = 0; i < len; i++)
17962 TREE_VEC_ELT (expanded_arguments, i) =
17963 tree_cons (NULL_TREE,
17964 TREE_VEC_ELT (expanded_exprs, i),
17965 TREE_VEC_ELT (expanded_arguments, i));
17968 in_base_initializer = 0;
17970 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17971 since we built them backwards. */
17972 for (i = 0; i < len; i++)
17974 TREE_VEC_ELT (expanded_arguments, i) =
17975 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17980 for (i = 0; i < len; ++i)
17982 if (expanded_bases)
17984 decl = TREE_VEC_ELT (expanded_bases, i);
17985 decl = expand_member_init (decl);
17986 init = TREE_VEC_ELT (expanded_arguments, i);
17990 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17991 tf_warning_or_error, NULL_TREE);
17993 decl = expand_member_init (decl);
17994 if (decl && !DECL_P (decl))
17995 in_base_initializer = 1;
17997 init = TREE_VALUE (t);
17998 if (init != void_type_node)
17999 init = tsubst_expr (init, argvec,
18000 tf_warning_or_error, NULL_TREE,
18001 /*integral_constant_expression_p=*/false);
18002 in_base_initializer = 0;
18007 init = build_tree_list (decl, init);
18008 TREE_CHAIN (init) = inits;
18016 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18019 set_current_access_from_decl (tree decl)
18021 if (TREE_PRIVATE (decl))
18022 current_access_specifier = access_private_node;
18023 else if (TREE_PROTECTED (decl))
18024 current_access_specifier = access_protected_node;
18026 current_access_specifier = access_public_node;
18029 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18030 is the instantiation (which should have been created with
18031 start_enum) and ARGS are the template arguments to use. */
18034 tsubst_enum (tree tag, tree newtag, tree args)
18038 if (SCOPED_ENUM_P (newtag))
18039 begin_scope (sk_scoped_enum, newtag);
18041 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18046 decl = TREE_VALUE (e);
18047 /* Note that in a template enum, the TREE_VALUE is the
18048 CONST_DECL, not the corresponding INTEGER_CST. */
18049 value = tsubst_expr (DECL_INITIAL (decl),
18050 args, tf_warning_or_error, NULL_TREE,
18051 /*integral_constant_expression_p=*/true);
18053 /* Give this enumeration constant the correct access. */
18054 set_current_access_from_decl (decl);
18056 /* Actually build the enumerator itself. */
18058 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
18061 if (SCOPED_ENUM_P (newtag))
18064 finish_enum_value_list (newtag);
18065 finish_enum (newtag);
18067 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
18068 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
18071 /* DECL is a FUNCTION_DECL that is a template specialization. Return
18072 its type -- but without substituting the innermost set of template
18073 arguments. So, innermost set of template parameters will appear in
18077 get_mostly_instantiated_function_type (tree decl)
18085 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
18086 targs = DECL_TI_ARGS (decl);
18087 tparms = DECL_TEMPLATE_PARMS (tmpl);
18088 parm_depth = TMPL_PARMS_DEPTH (tparms);
18090 /* There should be as many levels of arguments as there are levels
18092 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18094 fn_type = TREE_TYPE (tmpl);
18096 if (parm_depth == 1)
18097 /* No substitution is necessary. */
18104 /* Replace the innermost level of the TARGS with NULL_TREEs to
18105 let tsubst know not to substitute for those parameters. */
18106 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18107 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18108 SET_TMPL_ARGS_LEVEL (partial_args, i,
18109 TMPL_ARGS_LEVEL (targs, i));
18110 SET_TMPL_ARGS_LEVEL (partial_args,
18111 TMPL_ARGS_DEPTH (targs),
18112 make_tree_vec (DECL_NTPARMS (tmpl)));
18114 /* Make sure that we can see identifiers, and compute access
18116 push_access_scope (decl);
18118 ++processing_template_decl;
18119 /* Now, do the (partial) substitution to figure out the
18120 appropriate function type. */
18121 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
18122 --processing_template_decl;
18124 /* Substitute into the template parameters to obtain the real
18125 innermost set of parameters. This step is important if the
18126 innermost set of template parameters contains value
18127 parameters whose types depend on outer template parameters. */
18128 TREE_VEC_LENGTH (partial_args)--;
18129 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
18131 pop_access_scope (decl);
18137 /* Return truthvalue if we're processing a template different from
18138 the last one involved in diagnostics. */
18140 problematic_instantiation_changed (void)
18142 return last_template_error_tick != tinst_level_tick;
18145 /* Remember current template involved in diagnostics. */
18147 record_last_problematic_instantiation (void)
18149 last_template_error_tick = tinst_level_tick;
18152 struct tinst_level *
18153 current_instantiation (void)
18155 return current_tinst_level;
18158 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18159 type. Return zero for ok, nonzero for disallowed. Issue error and
18160 warning messages under control of COMPLAIN. */
18163 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18165 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18167 else if (POINTER_TYPE_P (type))
18169 else if (TYPE_PTR_TO_MEMBER_P (type))
18171 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18173 else if (TREE_CODE (type) == TYPENAME_TYPE)
18175 else if (TREE_CODE (type) == DECLTYPE_TYPE)
18178 if (complain & tf_error)
18179 error ("%q#T is not a valid type for a template constant parameter", type);
18183 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18184 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18187 dependent_type_p_r (tree type)
18193 A type is dependent if it is:
18195 -- a template parameter. Template template parameters are types
18196 for us (since TYPE_P holds true for them) so we handle
18198 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18199 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18201 /* -- a qualified-id with a nested-name-specifier which contains a
18202 class-name that names a dependent type or whose unqualified-id
18203 names a dependent type. */
18204 if (TREE_CODE (type) == TYPENAME_TYPE)
18206 /* -- a cv-qualified type where the cv-unqualified type is
18208 type = TYPE_MAIN_VARIANT (type);
18209 /* -- a compound type constructed from any dependent type. */
18210 if (TYPE_PTR_TO_MEMBER_P (type))
18211 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18212 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18214 else if (TREE_CODE (type) == POINTER_TYPE
18215 || TREE_CODE (type) == REFERENCE_TYPE)
18216 return dependent_type_p (TREE_TYPE (type));
18217 else if (TREE_CODE (type) == FUNCTION_TYPE
18218 || TREE_CODE (type) == METHOD_TYPE)
18222 if (dependent_type_p (TREE_TYPE (type)))
18224 for (arg_type = TYPE_ARG_TYPES (type);
18226 arg_type = TREE_CHAIN (arg_type))
18227 if (dependent_type_p (TREE_VALUE (arg_type)))
18231 /* -- an array type constructed from any dependent type or whose
18232 size is specified by a constant expression that is
18235 We checked for type- and value-dependence of the bounds in
18236 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18237 if (TREE_CODE (type) == ARRAY_TYPE)
18239 if (TYPE_DOMAIN (type)
18240 && dependent_type_p (TYPE_DOMAIN (type)))
18242 return dependent_type_p (TREE_TYPE (type));
18245 /* -- a template-id in which either the template name is a template
18247 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18249 /* ... or any of the template arguments is a dependent type or
18250 an expression that is type-dependent or value-dependent. */
18251 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18252 && (any_dependent_template_arguments_p
18253 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18256 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18257 dependent; if the argument of the `typeof' expression is not
18258 type-dependent, then it should already been have resolved. */
18259 if (TREE_CODE (type) == TYPEOF_TYPE
18260 || TREE_CODE (type) == DECLTYPE_TYPE
18261 || TREE_CODE (type) == UNDERLYING_TYPE)
18264 /* A template argument pack is dependent if any of its packed
18266 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18268 tree args = ARGUMENT_PACK_ARGS (type);
18269 int i, len = TREE_VEC_LENGTH (args);
18270 for (i = 0; i < len; ++i)
18271 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18275 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18276 be template parameters. */
18277 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18280 /* The standard does not specifically mention types that are local
18281 to template functions or local classes, but they should be
18282 considered dependent too. For example:
18284 template <int I> void f() {
18289 The size of `E' cannot be known until the value of `I' has been
18290 determined. Therefore, `E' must be considered dependent. */
18291 scope = TYPE_CONTEXT (type);
18292 if (scope && TYPE_P (scope))
18293 return dependent_type_p (scope);
18294 /* Don't use type_dependent_expression_p here, as it can lead
18295 to infinite recursion trying to determine whether a lambda
18296 nested in a lambda is dependent (c++/47687). */
18297 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
18298 && DECL_LANG_SPECIFIC (scope)
18299 && DECL_TEMPLATE_INFO (scope)
18300 && (any_dependent_template_arguments_p
18301 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
18304 /* Other types are non-dependent. */
18308 /* Returns TRUE if TYPE is dependent, in the sense of
18309 [temp.dep.type]. Note that a NULL type is considered dependent. */
18312 dependent_type_p (tree type)
18314 /* If there are no template parameters in scope, then there can't be
18315 any dependent types. */
18316 if (!processing_template_decl)
18318 /* If we are not processing a template, then nobody should be
18319 providing us with a dependent type. */
18321 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18325 /* If the type is NULL, we have not computed a type for the entity
18326 in question; in that case, the type is dependent. */
18330 /* Erroneous types can be considered non-dependent. */
18331 if (type == error_mark_node)
18334 /* If we have not already computed the appropriate value for TYPE,
18336 if (!TYPE_DEPENDENT_P_VALID (type))
18338 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18339 TYPE_DEPENDENT_P_VALID (type) = 1;
18342 return TYPE_DEPENDENT_P (type);
18345 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18346 lookup. In other words, a dependent type that is not the current
18350 dependent_scope_p (tree scope)
18352 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18353 && !currently_open_class (scope));
18356 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18357 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18360 /* Note that this predicate is not appropriate for general expressions;
18361 only constant expressions (that satisfy potential_constant_expression)
18362 can be tested for value dependence.
18364 We should really also have a predicate for "instantiation-dependent".
18366 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18367 (what about instantiation-dependent constant-expressions?)
18368 is_late_template_attribute: defer if instantiation-dependent.
18369 compute_array_index_type: proceed if constant and not t- or v-dependent
18370 if instantiation-dependent, need to remember full expression
18371 uses_template_parms: FIXME - need to audit callers
18372 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18373 dependent_type_p [array_type]: dependent if index type is dependent
18375 static_assert - instantiation-dependent */
18378 value_dependent_expression_p (tree expression)
18380 if (!processing_template_decl)
18383 /* A name declared with a dependent type. */
18384 if (DECL_P (expression) && type_dependent_expression_p (expression))
18387 switch (TREE_CODE (expression))
18389 case IDENTIFIER_NODE:
18390 /* A name that has not been looked up -- must be dependent. */
18393 case TEMPLATE_PARM_INDEX:
18394 /* A non-type template parm. */
18398 /* A non-type template parm. */
18399 if (DECL_TEMPLATE_PARM_P (expression))
18401 return value_dependent_expression_p (DECL_INITIAL (expression));
18404 /* A constant with literal type and is initialized
18405 with an expression that is value-dependent. */
18406 if (DECL_INITIAL (expression)
18407 && decl_constant_var_p (expression)
18408 && value_dependent_expression_p (DECL_INITIAL (expression)))
18412 case DYNAMIC_CAST_EXPR:
18413 case STATIC_CAST_EXPR:
18414 case CONST_CAST_EXPR:
18415 case REINTERPRET_CAST_EXPR:
18417 /* These expressions are value-dependent if the type to which
18418 the cast occurs is dependent or the expression being casted
18419 is value-dependent. */
18421 tree type = TREE_TYPE (expression);
18423 if (dependent_type_p (type))
18426 /* A functional cast has a list of operands. */
18427 expression = TREE_OPERAND (expression, 0);
18430 /* If there are no operands, it must be an expression such
18431 as "int()". This should not happen for aggregate types
18432 because it would form non-constant expressions. */
18433 gcc_assert (cxx_dialect >= cxx0x
18434 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18439 if (TREE_CODE (expression) == TREE_LIST)
18440 return any_value_dependent_elements_p (expression);
18442 return value_dependent_expression_p (expression);
18448 /* A `sizeof' expression is value-dependent if the operand is
18449 type-dependent or is a pack expansion. */
18450 expression = TREE_OPERAND (expression, 0);
18451 if (PACK_EXPANSION_P (expression))
18453 else if (TYPE_P (expression))
18454 return dependent_type_p (expression);
18455 return type_dependent_expression_p (expression);
18457 case AT_ENCODE_EXPR:
18458 /* An 'encode' expression is value-dependent if the operand is
18460 expression = TREE_OPERAND (expression, 0);
18461 return dependent_type_p (expression);
18463 case NOEXCEPT_EXPR:
18464 expression = TREE_OPERAND (expression, 0);
18465 return type_dependent_expression_p (expression);
18469 tree name = TREE_OPERAND (expression, 1);
18470 return value_dependent_expression_p (name);
18473 case COMPONENT_REF:
18474 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18475 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18477 case NONTYPE_ARGUMENT_PACK:
18478 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18479 is value-dependent. */
18481 tree values = ARGUMENT_PACK_ARGS (expression);
18482 int i, len = TREE_VEC_LENGTH (values);
18484 for (i = 0; i < len; ++i)
18485 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
18493 tree type2 = TRAIT_EXPR_TYPE2 (expression);
18494 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
18495 || (type2 ? dependent_type_p (type2) : false));
18499 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18500 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
18503 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18504 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
18508 tree op = TREE_OPERAND (expression, 0);
18509 return (value_dependent_expression_p (op)
18510 || has_value_dependent_address (op));
18515 tree fn = get_callee_fndecl (expression);
18517 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
18519 nargs = call_expr_nargs (expression);
18520 for (i = 0; i < nargs; ++i)
18522 tree op = CALL_EXPR_ARG (expression, i);
18523 /* In a call to a constexpr member function, look through the
18524 implicit ADDR_EXPR on the object argument so that it doesn't
18525 cause the call to be considered value-dependent. We also
18526 look through it in potential_constant_expression. */
18527 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
18528 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
18529 && TREE_CODE (op) == ADDR_EXPR)
18530 op = TREE_OPERAND (op, 0);
18531 if (value_dependent_expression_p (op))
18537 case TEMPLATE_ID_EXPR:
18538 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
18540 return type_dependent_expression_p (expression);
18546 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
18547 if (value_dependent_expression_p (val))
18553 /* A constant expression is value-dependent if any subexpression is
18554 value-dependent. */
18555 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
18557 case tcc_reference:
18559 case tcc_comparison:
18561 case tcc_expression:
18564 int i, len = cp_tree_operand_length (expression);
18566 for (i = 0; i < len; i++)
18568 tree t = TREE_OPERAND (expression, i);
18570 /* In some cases, some of the operands may be missing.l
18571 (For example, in the case of PREDECREMENT_EXPR, the
18572 amount to increment by may be missing.) That doesn't
18573 make the expression dependent. */
18574 if (t && value_dependent_expression_p (t))
18585 /* The expression is not value-dependent. */
18589 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
18590 [temp.dep.expr]. Note that an expression with no type is
18591 considered dependent. Other parts of the compiler arrange for an
18592 expression with type-dependent subexpressions to have no type, so
18593 this function doesn't have to be fully recursive. */
18596 type_dependent_expression_p (tree expression)
18598 if (!processing_template_decl)
18601 if (expression == error_mark_node)
18604 /* An unresolved name is always dependent. */
18605 if (TREE_CODE (expression) == IDENTIFIER_NODE
18606 || TREE_CODE (expression) == USING_DECL)
18609 /* Some expression forms are never type-dependent. */
18610 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
18611 || TREE_CODE (expression) == SIZEOF_EXPR
18612 || TREE_CODE (expression) == ALIGNOF_EXPR
18613 || TREE_CODE (expression) == AT_ENCODE_EXPR
18614 || TREE_CODE (expression) == NOEXCEPT_EXPR
18615 || TREE_CODE (expression) == TRAIT_EXPR
18616 || TREE_CODE (expression) == TYPEID_EXPR
18617 || TREE_CODE (expression) == DELETE_EXPR
18618 || TREE_CODE (expression) == VEC_DELETE_EXPR
18619 || TREE_CODE (expression) == THROW_EXPR)
18622 /* The types of these expressions depends only on the type to which
18623 the cast occurs. */
18624 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
18625 || TREE_CODE (expression) == STATIC_CAST_EXPR
18626 || TREE_CODE (expression) == CONST_CAST_EXPR
18627 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
18628 || TREE_CODE (expression) == CAST_EXPR)
18629 return dependent_type_p (TREE_TYPE (expression));
18631 /* The types of these expressions depends only on the type created
18632 by the expression. */
18633 if (TREE_CODE (expression) == NEW_EXPR
18634 || TREE_CODE (expression) == VEC_NEW_EXPR)
18636 /* For NEW_EXPR tree nodes created inside a template, either
18637 the object type itself or a TREE_LIST may appear as the
18639 tree type = TREE_OPERAND (expression, 1);
18640 if (TREE_CODE (type) == TREE_LIST)
18641 /* This is an array type. We need to check array dimensions
18643 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
18644 || value_dependent_expression_p
18645 (TREE_OPERAND (TREE_VALUE (type), 1));
18647 return dependent_type_p (type);
18650 if (TREE_CODE (expression) == SCOPE_REF)
18652 tree scope = TREE_OPERAND (expression, 0);
18653 tree name = TREE_OPERAND (expression, 1);
18655 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
18656 contains an identifier associated by name lookup with one or more
18657 declarations declared with a dependent type, or...a
18658 nested-name-specifier or qualified-id that names a member of an
18659 unknown specialization. */
18660 return (type_dependent_expression_p (name)
18661 || dependent_scope_p (scope));
18664 if (TREE_CODE (expression) == FUNCTION_DECL
18665 && DECL_LANG_SPECIFIC (expression)
18666 && DECL_TEMPLATE_INFO (expression)
18667 && (any_dependent_template_arguments_p
18668 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
18671 if (TREE_CODE (expression) == TEMPLATE_DECL
18672 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
18675 if (TREE_CODE (expression) == STMT_EXPR)
18676 expression = stmt_expr_value_expr (expression);
18678 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
18683 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
18685 if (type_dependent_expression_p (elt))
18691 /* A static data member of the current instantiation with incomplete
18692 array type is type-dependent, as the definition and specializations
18693 can have different bounds. */
18694 if (TREE_CODE (expression) == VAR_DECL
18695 && DECL_CLASS_SCOPE_P (expression)
18696 && dependent_type_p (DECL_CONTEXT (expression))
18697 && VAR_HAD_UNKNOWN_BOUND (expression))
18700 if (TREE_TYPE (expression) == unknown_type_node)
18702 if (TREE_CODE (expression) == ADDR_EXPR)
18703 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
18704 if (TREE_CODE (expression) == COMPONENT_REF
18705 || TREE_CODE (expression) == OFFSET_REF)
18707 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
18709 expression = TREE_OPERAND (expression, 1);
18710 if (TREE_CODE (expression) == IDENTIFIER_NODE)
18713 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
18714 if (TREE_CODE (expression) == SCOPE_REF)
18717 if (TREE_CODE (expression) == BASELINK)
18718 expression = BASELINK_FUNCTIONS (expression);
18720 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
18722 if (any_dependent_template_arguments_p
18723 (TREE_OPERAND (expression, 1)))
18725 expression = TREE_OPERAND (expression, 0);
18727 gcc_assert (TREE_CODE (expression) == OVERLOAD
18728 || TREE_CODE (expression) == FUNCTION_DECL);
18732 if (type_dependent_expression_p (OVL_CURRENT (expression)))
18734 expression = OVL_NEXT (expression);
18739 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
18741 return (dependent_type_p (TREE_TYPE (expression)));
18744 /* Like type_dependent_expression_p, but it also works while not processing
18745 a template definition, i.e. during substitution or mangling. */
18748 type_dependent_expression_p_push (tree expr)
18751 ++processing_template_decl;
18752 b = type_dependent_expression_p (expr);
18753 --processing_template_decl;
18757 /* Returns TRUE if ARGS contains a type-dependent expression. */
18760 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
18765 FOR_EACH_VEC_ELT (tree, args, i, arg)
18767 if (type_dependent_expression_p (arg))
18773 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18774 expressions) contains any type-dependent expressions. */
18777 any_type_dependent_elements_p (const_tree list)
18779 for (; list; list = TREE_CHAIN (list))
18780 if (value_dependent_expression_p (TREE_VALUE (list)))
18786 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18787 expressions) contains any value-dependent expressions. */
18790 any_value_dependent_elements_p (const_tree list)
18792 for (; list; list = TREE_CHAIN (list))
18793 if (value_dependent_expression_p (TREE_VALUE (list)))
18799 /* Returns TRUE if the ARG (a template argument) is dependent. */
18802 dependent_template_arg_p (tree arg)
18804 if (!processing_template_decl)
18807 /* Assume a template argument that was wrongly written by the user
18808 is dependent. This is consistent with what
18809 any_dependent_template_arguments_p [that calls this function]
18811 if (arg == error_mark_node)
18814 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
18815 arg = ARGUMENT_PACK_SELECT_ARG (arg);
18817 if (TREE_CODE (arg) == TEMPLATE_DECL
18818 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18819 return dependent_template_p (arg);
18820 else if (ARGUMENT_PACK_P (arg))
18822 tree args = ARGUMENT_PACK_ARGS (arg);
18823 int i, len = TREE_VEC_LENGTH (args);
18824 for (i = 0; i < len; ++i)
18826 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18832 else if (TYPE_P (arg))
18833 return dependent_type_p (arg);
18835 return (type_dependent_expression_p (arg)
18836 || value_dependent_expression_p (arg));
18839 /* Returns true if ARGS (a collection of template arguments) contains
18840 any types that require structural equality testing. */
18843 any_template_arguments_need_structural_equality_p (tree args)
18850 if (args == error_mark_node)
18853 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18855 tree level = TMPL_ARGS_LEVEL (args, i + 1);
18856 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18858 tree arg = TREE_VEC_ELT (level, j);
18859 tree packed_args = NULL_TREE;
18862 if (ARGUMENT_PACK_P (arg))
18864 /* Look inside the argument pack. */
18865 packed_args = ARGUMENT_PACK_ARGS (arg);
18866 len = TREE_VEC_LENGTH (packed_args);
18869 for (k = 0; k < len; ++k)
18872 arg = TREE_VEC_ELT (packed_args, k);
18874 if (error_operand_p (arg))
18876 else if (TREE_CODE (arg) == TEMPLATE_DECL
18877 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18879 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18881 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18882 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18891 /* Returns true if ARGS (a collection of template arguments) contains
18892 any dependent arguments. */
18895 any_dependent_template_arguments_p (const_tree args)
18902 if (args == error_mark_node)
18905 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18907 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18908 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18909 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18916 /* Returns TRUE if the template TMPL is dependent. */
18919 dependent_template_p (tree tmpl)
18921 if (TREE_CODE (tmpl) == OVERLOAD)
18925 if (dependent_template_p (OVL_CURRENT (tmpl)))
18927 tmpl = OVL_NEXT (tmpl);
18932 /* Template template parameters are dependent. */
18933 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18934 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18936 /* So are names that have not been looked up. */
18937 if (TREE_CODE (tmpl) == SCOPE_REF
18938 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18940 /* So are member templates of dependent classes. */
18941 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18942 return dependent_type_p (DECL_CONTEXT (tmpl));
18946 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18949 dependent_template_id_p (tree tmpl, tree args)
18951 return (dependent_template_p (tmpl)
18952 || any_dependent_template_arguments_p (args));
18955 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18959 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18963 if (!processing_template_decl)
18966 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18968 tree decl = TREE_VEC_ELT (declv, i);
18969 tree init = TREE_VEC_ELT (initv, i);
18970 tree cond = TREE_VEC_ELT (condv, i);
18971 tree incr = TREE_VEC_ELT (incrv, i);
18973 if (type_dependent_expression_p (decl))
18976 if (init && type_dependent_expression_p (init))
18979 if (type_dependent_expression_p (cond))
18982 if (COMPARISON_CLASS_P (cond)
18983 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18984 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18987 if (TREE_CODE (incr) == MODOP_EXPR)
18989 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18990 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18993 else if (type_dependent_expression_p (incr))
18995 else if (TREE_CODE (incr) == MODIFY_EXPR)
18997 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18999 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19001 tree t = TREE_OPERAND (incr, 1);
19002 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19003 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19012 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19013 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19014 no such TYPE can be found. Note that this function peers inside
19015 uninstantiated templates and therefore should be used only in
19016 extremely limited situations. ONLY_CURRENT_P restricts this
19017 peering to the currently open classes hierarchy (which is required
19018 when comparing types). */
19021 resolve_typename_type (tree type, bool only_current_p)
19030 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19032 scope = TYPE_CONTEXT (type);
19033 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19034 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19035 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19036 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19037 identifier of the TYPENAME_TYPE anymore.
19038 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19039 TYPENAME_TYPE instead, we avoid messing up with a possible
19040 typedef variant case. */
19041 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
19043 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
19044 it first before we can figure out what NAME refers to. */
19045 if (TREE_CODE (scope) == TYPENAME_TYPE)
19046 scope = resolve_typename_type (scope, only_current_p);
19047 /* If we don't know what SCOPE refers to, then we cannot resolve the
19049 if (TREE_CODE (scope) == TYPENAME_TYPE)
19051 /* If the SCOPE is a template type parameter, we have no way of
19052 resolving the name. */
19053 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
19055 /* If the SCOPE is not the current instantiation, there's no reason
19056 to look inside it. */
19057 if (only_current_p && !currently_open_class (scope))
19059 /* If this is a typedef, we don't want to look inside (c++/11987). */
19060 if (typedef_variant_p (type))
19062 /* If SCOPE isn't the template itself, it will not have a valid
19063 TYPE_FIELDS list. */
19064 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
19065 /* scope is either the template itself or a compatible instantiation
19066 like X<T>, so look up the name in the original template. */
19067 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
19069 /* scope is a partial instantiation, so we can't do the lookup or we
19070 will lose the template arguments. */
19072 /* Enter the SCOPE so that name lookup will be resolved as if we
19073 were in the class definition. In particular, SCOPE will no
19074 longer be considered a dependent type. */
19075 pushed_scope = push_scope (scope);
19076 /* Look up the declaration. */
19077 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
19079 result = NULL_TREE;
19081 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
19082 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
19085 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
19086 && TREE_CODE (decl) == TYPE_DECL)
19088 result = TREE_TYPE (decl);
19089 if (result == error_mark_node)
19090 result = NULL_TREE;
19092 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19093 && DECL_CLASS_TEMPLATE_P (decl))
19097 /* Obtain the template and the arguments. */
19098 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19099 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19100 /* Instantiate the template. */
19101 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
19102 /*entering_scope=*/0,
19103 tf_error | tf_user);
19104 if (result == error_mark_node)
19105 result = NULL_TREE;
19108 /* Leave the SCOPE. */
19110 pop_scope (pushed_scope);
19112 /* If we failed to resolve it, return the original typename. */
19116 /* If lookup found a typename type, resolve that too. */
19117 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
19119 /* Ill-formed programs can cause infinite recursion here, so we
19120 must catch that. */
19121 TYPENAME_IS_RESOLVING_P (type) = 1;
19122 result = resolve_typename_type (result, only_current_p);
19123 TYPENAME_IS_RESOLVING_P (type) = 0;
19126 /* Qualify the resulting type. */
19127 quals = cp_type_quals (type);
19129 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
19134 /* EXPR is an expression which is not type-dependent. Return a proxy
19135 for EXPR that can be used to compute the types of larger
19136 expressions containing EXPR. */
19139 build_non_dependent_expr (tree expr)
19143 #ifdef ENABLE_CHECKING
19144 /* Try to get a constant value for all non-type-dependent expressions in
19145 order to expose bugs in *_dependent_expression_p and constexpr. */
19146 if (cxx_dialect >= cxx0x)
19147 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
19150 /* Preserve OVERLOADs; the functions must be available to resolve
19153 if (TREE_CODE (inner_expr) == STMT_EXPR)
19154 inner_expr = stmt_expr_value_expr (inner_expr);
19155 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19156 inner_expr = TREE_OPERAND (inner_expr, 0);
19157 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19158 inner_expr = TREE_OPERAND (inner_expr, 1);
19159 if (is_overloaded_fn (inner_expr)
19160 || TREE_CODE (inner_expr) == OFFSET_REF)
19162 /* There is no need to return a proxy for a variable. */
19163 if (TREE_CODE (expr) == VAR_DECL)
19165 /* Preserve string constants; conversions from string constants to
19166 "char *" are allowed, even though normally a "const char *"
19167 cannot be used to initialize a "char *". */
19168 if (TREE_CODE (expr) == STRING_CST)
19170 /* Preserve arithmetic constants, as an optimization -- there is no
19171 reason to create a new node. */
19172 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19174 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19175 There is at least one place where we want to know that a
19176 particular expression is a throw-expression: when checking a ?:
19177 expression, there are special rules if the second or third
19178 argument is a throw-expression. */
19179 if (TREE_CODE (expr) == THROW_EXPR)
19182 if (TREE_CODE (expr) == COND_EXPR)
19183 return build3 (COND_EXPR,
19185 TREE_OPERAND (expr, 0),
19186 (TREE_OPERAND (expr, 1)
19187 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19188 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19189 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19190 if (TREE_CODE (expr) == COMPOUND_EXPR
19191 && !COMPOUND_EXPR_OVERLOADED (expr))
19192 return build2 (COMPOUND_EXPR,
19194 TREE_OPERAND (expr, 0),
19195 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19197 /* If the type is unknown, it can't really be non-dependent */
19198 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19200 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19201 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19204 /* ARGS is a vector of expressions as arguments to a function call.
19205 Replace the arguments with equivalent non-dependent expressions.
19206 This modifies ARGS in place. */
19209 make_args_non_dependent (VEC(tree,gc) *args)
19214 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19216 tree newarg = build_non_dependent_expr (arg);
19218 VEC_replace (tree, args, ix, newarg);
19222 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19223 with a level one deeper than the actual template parms. */
19228 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19229 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19230 TYPE_DECL, get_identifier ("auto"), au);
19231 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19232 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19233 (0, processing_template_decl + 1, processing_template_decl + 1,
19234 0, TYPE_NAME (au), NULL_TREE);
19235 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19236 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19237 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19242 /* Given type ARG, return std::initializer_list<ARG>. */
19247 tree std_init_list = namespace_binding
19248 (get_identifier ("initializer_list"), std_node);
19250 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19252 error ("deducing from brace-enclosed initializer list requires "
19253 "#include <initializer_list>");
19254 return error_mark_node;
19256 argvec = make_tree_vec (1);
19257 TREE_VEC_ELT (argvec, 0) = arg;
19258 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19259 NULL_TREE, 0, tf_warning_or_error);
19262 /* Replace auto in TYPE with std::initializer_list<auto>. */
19265 listify_autos (tree type, tree auto_node)
19267 tree init_auto = listify (auto_node);
19268 tree argvec = make_tree_vec (1);
19269 TREE_VEC_ELT (argvec, 0) = init_auto;
19270 if (processing_template_decl)
19271 argvec = add_to_template_args (current_template_args (), argvec);
19272 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19275 /* walk_tree helper for do_auto_deduction. */
19278 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19281 /* Is this a variable with the type we're looking for? */
19283 && TREE_TYPE (*tp) == type)
19289 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19290 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19293 do_auto_deduction (tree type, tree init, tree auto_node)
19295 tree parms, tparms, targs;
19300 /* The name of the object being declared shall not appear in the
19301 initializer expression. */
19302 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19305 error ("variable %q#D with %<auto%> type used in its own "
19306 "initializer", decl);
19307 return error_mark_node;
19310 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19311 with either a new invented type template parameter U or, if the
19312 initializer is a braced-init-list (8.5.4), with
19313 std::initializer_list<U>. */
19314 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19315 type = listify_autos (type, auto_node);
19317 init = resolve_nondeduced_context (init);
19319 parms = build_tree_list (NULL_TREE, type);
19321 tparms = make_tree_vec (1);
19322 targs = make_tree_vec (1);
19323 TREE_VEC_ELT (tparms, 0)
19324 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19325 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19326 DEDUCE_CALL, LOOKUP_NORMAL);
19329 if (type && type != error_mark_node)
19330 /* If type is error_mark_node a diagnostic must have been
19331 emitted by now. Also, having a mention to '<type error>'
19332 in the diagnostic is not really useful to the user. */
19333 error ("unable to deduce %qT from %qE", type, init);
19334 return error_mark_node;
19337 /* If the list of declarators contains more than one declarator, the type
19338 of each declared variable is determined as described above. If the
19339 type deduced for the template parameter U is not the same in each
19340 deduction, the program is ill-formed. */
19341 if (TREE_TYPE (auto_node)
19342 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19344 error ("inconsistent deduction for %qT: %qT and then %qT",
19345 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19346 return error_mark_node;
19348 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19350 if (processing_template_decl)
19351 targs = add_to_template_args (current_template_args (), targs);
19352 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19355 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19359 splice_late_return_type (tree type, tree late_return_type)
19363 if (late_return_type == NULL_TREE)
19365 argvec = make_tree_vec (1);
19366 TREE_VEC_ELT (argvec, 0) = late_return_type;
19367 if (processing_template_parmlist)
19368 /* For a late-specified return type in a template type-parameter, we
19369 need to add a dummy argument level for its parmlist. */
19370 argvec = add_to_template_args
19371 (make_tree_vec (processing_template_parmlist), argvec);
19372 if (current_template_parms)
19373 argvec = add_to_template_args (current_template_args (), argvec);
19374 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19377 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19380 is_auto (const_tree type)
19382 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19383 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
19389 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
19390 appear as a type-specifier for the declaration in question, we don't
19391 have to look through the whole type. */
19394 type_uses_auto (tree type)
19396 enum tree_code code;
19397 if (is_auto (type))
19400 code = TREE_CODE (type);
19402 if (code == POINTER_TYPE || code == REFERENCE_TYPE
19403 || code == OFFSET_TYPE || code == FUNCTION_TYPE
19404 || code == METHOD_TYPE || code == ARRAY_TYPE)
19405 return type_uses_auto (TREE_TYPE (type));
19407 if (TYPE_PTRMEMFUNC_P (type))
19408 return type_uses_auto (TREE_TYPE (TREE_TYPE
19409 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
19414 /* For a given template T, return the vector of typedefs referenced
19415 in T for which access check is needed at T instantiation time.
19416 T is either a FUNCTION_DECL or a RECORD_TYPE.
19417 Those typedefs were added to T by the function
19418 append_type_to_template_for_access_check. */
19420 VEC(qualified_typedef_usage_t,gc)*
19421 get_types_needing_access_check (tree t)
19424 VEC(qualified_typedef_usage_t,gc) *result = NULL;
19426 if (!t || t == error_mark_node)
19429 if (!(ti = get_template_info (t)))
19432 if (CLASS_TYPE_P (t)
19433 || TREE_CODE (t) == FUNCTION_DECL)
19435 if (!TI_TEMPLATE (ti))
19438 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19444 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19445 tied to T. That list of typedefs will be access checked at
19446 T instantiation time.
19447 T is either a FUNCTION_DECL or a RECORD_TYPE.
19448 TYPE_DECL is a TYPE_DECL node representing a typedef.
19449 SCOPE is the scope through which TYPE_DECL is accessed.
19450 LOCATION is the location of the usage point of TYPE_DECL.
19452 This function is a subroutine of
19453 append_type_to_template_for_access_check. */
19456 append_type_to_template_for_access_check_1 (tree t,
19459 location_t location)
19461 qualified_typedef_usage_t typedef_usage;
19464 if (!t || t == error_mark_node)
19467 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19468 || CLASS_TYPE_P (t))
19470 && TREE_CODE (type_decl) == TYPE_DECL
19473 if (!(ti = get_template_info (t)))
19476 gcc_assert (TI_TEMPLATE (ti));
19478 typedef_usage.typedef_decl = type_decl;
19479 typedef_usage.context = scope;
19480 typedef_usage.locus = location;
19482 VEC_safe_push (qualified_typedef_usage_t, gc,
19483 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
19487 /* Append TYPE_DECL to the template TEMPL.
19488 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
19489 At TEMPL instanciation time, TYPE_DECL will be checked to see
19490 if it can be accessed through SCOPE.
19491 LOCATION is the location of the usage point of TYPE_DECL.
19493 e.g. consider the following code snippet:
19500 template<class U> struct S
19502 C::myint mi; // <-- usage point of the typedef C::myint
19507 At S<char> instantiation time, we need to check the access of C::myint
19508 In other words, we need to check the access of the myint typedef through
19509 the C scope. For that purpose, this function will add the myint typedef
19510 and the scope C through which its being accessed to a list of typedefs
19511 tied to the template S. That list will be walked at template instantiation
19512 time and access check performed on each typedefs it contains.
19513 Note that this particular code snippet should yield an error because
19514 myint is private to C. */
19517 append_type_to_template_for_access_check (tree templ,
19520 location_t location)
19522 qualified_typedef_usage_t *iter;
19525 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
19527 /* Make sure we don't append the type to the template twice. */
19528 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
19529 get_types_needing_access_check (templ),
19531 if (iter->typedef_decl == type_decl && scope == iter->context)
19534 append_type_to_template_for_access_check_1 (templ, type_decl,
19538 /* Set up the hash tables for template instantiations. */
19541 init_template_processing (void)
19543 decl_specializations = htab_create_ggc (37,
19544 hash_specialization,
19545 eq_specializations,
19547 type_specializations = htab_create_ggc (37,
19548 hash_specialization,
19549 eq_specializations,
19553 /* Print stats about the template hash tables for -fstats. */
19556 print_template_statistics (void)
19558 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
19559 "%f collisions\n", (long) htab_size (decl_specializations),
19560 (long) htab_elements (decl_specializations),
19561 htab_collisions (decl_specializations));
19562 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
19563 "%f collisions\n", (long) htab_size (type_specializations),
19564 (long) htab_elements (type_specializations),
19565 htab_collisions (type_specializations));
19568 #include "gt-cp-pt.h"