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
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 "cp-objcp-common.h"
40 #include "tree-inline.h"
45 #include "tree-iterator.h"
48 /* The type of functions taking a tree, and some additional data, and
50 typedef int (*tree_fn_t) (tree, void*);
52 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
53 instantiations have been deferred, either because their definitions
54 were not yet available, or because we were putting off doing the work. */
55 struct GTY (()) pending_template {
56 struct pending_template *next;
57 struct tinst_level *tinst;
60 static GTY(()) struct pending_template *pending_templates;
61 static GTY(()) struct pending_template *last_pending_template;
63 int processing_template_parmlist;
64 static int template_header_count;
66 static GTY(()) tree saved_trees;
67 static VEC(int,heap) *inline_parm_levels;
69 static GTY(()) struct tinst_level *current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 typedef struct GTY(()) spec_entry
90 static GTY ((param_is (spec_entry)))
91 htab_t decl_specializations;
93 static GTY ((param_is (spec_entry)))
94 htab_t type_specializations;
96 /* Contains canonical template parameter types. The vector is indexed by
97 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
98 TREE_LIST, whose TREE_VALUEs contain the canonical template
99 parameters of various types and levels. */
100 static GTY(()) VEC(tree,gc) *canonical_template_parms;
102 #define UNIFY_ALLOW_NONE 0
103 #define UNIFY_ALLOW_MORE_CV_QUAL 1
104 #define UNIFY_ALLOW_LESS_CV_QUAL 2
105 #define UNIFY_ALLOW_DERIVED 4
106 #define UNIFY_ALLOW_INTEGER 8
107 #define UNIFY_ALLOW_OUTER_LEVEL 16
108 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
109 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
111 static void push_access_scope (tree);
112 static void pop_access_scope (tree);
113 static bool resolve_overloaded_unification (tree, tree, tree, tree,
114 unification_kind_t, int);
115 static int try_one_overload (tree, tree, tree, tree, tree,
116 unification_kind_t, int, bool);
117 static int unify (tree, tree, tree, tree, int);
118 static void add_pending_template (tree);
119 static tree reopen_tinst_level (struct tinst_level *);
120 static tree tsubst_initializer_list (tree, tree);
121 static tree get_class_bindings (tree, tree, tree);
122 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
124 static void tsubst_enum (tree, tree, tree);
125 static tree add_to_template_args (tree, tree);
126 static tree add_outermost_template_args (tree, tree);
127 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
128 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
130 static int type_unification_real (tree, tree, tree, const tree *,
131 unsigned int, int, unification_kind_t, int);
132 static void note_template_header (int);
133 static tree convert_nontype_argument_function (tree, tree);
134 static tree convert_nontype_argument (tree, tree);
135 static tree convert_template_argument (tree, tree, tree,
136 tsubst_flags_t, int, tree);
137 static int for_each_template_parm (tree, tree_fn_t, void*,
138 struct pointer_set_t*, bool);
139 static tree expand_template_argument_pack (tree);
140 static tree build_template_parm_index (int, int, int, tree, tree);
141 static bool inline_needs_template_parms (tree);
142 static void push_inline_template_parms_recursive (tree, int);
143 static tree retrieve_local_specialization (tree);
144 static void register_local_specialization (tree, tree);
145 static hashval_t hash_specialization (const void *p);
146 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
147 static int mark_template_parm (tree, void *);
148 static int template_parm_this_level_p (tree, void *);
149 static tree tsubst_friend_function (tree, tree);
150 static tree tsubst_friend_class (tree, tree);
151 static int can_complete_type_without_circularity (tree);
152 static tree get_bindings (tree, tree, tree, bool);
153 static int template_decl_level (tree);
154 static int check_cv_quals_for_unify (int, tree, tree);
155 static void template_parm_level_and_index (tree, int*, int*);
156 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
157 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
158 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
159 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
160 static void regenerate_decl_from_template (tree, tree);
161 static tree most_specialized_class (tree, tree, tsubst_flags_t);
162 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
163 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
165 static bool check_specialization_scope (void);
166 static tree process_partial_specialization (tree);
167 static void set_current_access_from_decl (tree);
168 static tree get_template_base (tree, tree, tree, tree);
169 static tree try_class_unification (tree, tree, tree, tree);
170 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
172 static bool template_template_parm_bindings_ok_p (tree, tree);
173 static int template_args_equal (tree, tree);
174 static void tsubst_default_arguments (tree);
175 static tree for_each_template_parm_r (tree *, int *, void *);
176 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
177 static void copy_default_args_to_explicit_spec (tree);
178 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
179 static int eq_local_specializations (const void *, const void *);
180 static bool dependent_template_arg_p (tree);
181 static bool any_template_arguments_need_structural_equality_p (tree);
182 static bool dependent_type_p_r (tree);
183 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
184 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
185 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
186 static tree tsubst_decl (tree, tree, tsubst_flags_t);
187 static void perform_typedefs_access_check (tree tmpl, tree targs);
188 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
190 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
191 static tree listify (tree);
192 static tree listify_autos (tree, tree);
194 /* Make the current scope suitable for access checking when we are
195 processing T. T can be FUNCTION_DECL for instantiated function
196 template, or VAR_DECL for static member variable (need by
197 instantiate_decl). */
200 push_access_scope (tree t)
202 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
203 || TREE_CODE (t) == VAR_DECL);
205 if (DECL_FRIEND_CONTEXT (t))
206 push_nested_class (DECL_FRIEND_CONTEXT (t));
207 else if (DECL_CLASS_SCOPE_P (t))
208 push_nested_class (DECL_CONTEXT (t));
210 push_to_top_level ();
212 if (TREE_CODE (t) == FUNCTION_DECL)
214 saved_access_scope = tree_cons
215 (NULL_TREE, current_function_decl, saved_access_scope);
216 current_function_decl = t;
220 /* Restore the scope set up by push_access_scope. T is the node we
224 pop_access_scope (tree t)
226 if (TREE_CODE (t) == FUNCTION_DECL)
228 current_function_decl = TREE_VALUE (saved_access_scope);
229 saved_access_scope = TREE_CHAIN (saved_access_scope);
232 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
235 pop_from_top_level ();
238 /* Do any processing required when DECL (a member template
239 declaration) is finished. Returns the TEMPLATE_DECL corresponding
240 to DECL, unless it is a specialization, in which case the DECL
241 itself is returned. */
244 finish_member_template_decl (tree decl)
246 if (decl == error_mark_node)
247 return error_mark_node;
249 gcc_assert (DECL_P (decl));
251 if (TREE_CODE (decl) == TYPE_DECL)
255 type = TREE_TYPE (decl);
256 if (type == error_mark_node)
257 return error_mark_node;
258 if (MAYBE_CLASS_TYPE_P (type)
259 && CLASSTYPE_TEMPLATE_INFO (type)
260 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
262 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
263 check_member_template (tmpl);
268 else if (TREE_CODE (decl) == FIELD_DECL)
269 error ("data member %qD cannot be a member template", decl);
270 else if (DECL_TEMPLATE_INFO (decl))
272 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
274 check_member_template (DECL_TI_TEMPLATE (decl));
275 return DECL_TI_TEMPLATE (decl);
281 error ("invalid member template declaration %qD", decl);
283 return error_mark_node;
286 /* Create a template info node. */
289 build_template_info (tree template_decl, tree template_args)
291 tree result = make_node (TEMPLATE_INFO);
292 TI_TEMPLATE (result) = template_decl;
293 TI_ARGS (result) = template_args;
297 /* Return the template info node corresponding to T, whatever T is. */
300 get_template_info (const_tree t)
302 tree tinfo = NULL_TREE;
304 if (!t || t == error_mark_node)
307 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
308 tinfo = DECL_TEMPLATE_INFO (t);
310 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
313 if (TAGGED_TYPE_P (t))
314 tinfo = TYPE_TEMPLATE_INFO (t);
315 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
316 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
321 /* Returns the template nesting level of the indicated class TYPE.
331 A<T>::B<U> has depth two, while A<T> has depth one.
332 Both A<T>::B<int> and A<int>::B<U> have depth one, if
333 they are instantiations, not specializations.
335 This function is guaranteed to return 0 if passed NULL_TREE so
336 that, for example, `template_class_depth (current_class_type)' is
340 template_class_depth (tree type)
345 type && TREE_CODE (type) != NAMESPACE_DECL;
346 type = (TREE_CODE (type) == FUNCTION_DECL)
347 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
349 tree tinfo = get_template_info (type);
351 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
352 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
359 /* Subroutine of maybe_begin_member_template_processing.
360 Returns true if processing DECL needs us to push template parms. */
363 inline_needs_template_parms (tree decl)
365 if (! DECL_TEMPLATE_INFO (decl))
368 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
369 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
372 /* Subroutine of maybe_begin_member_template_processing.
373 Push the template parms in PARMS, starting from LEVELS steps into the
374 chain, and ending at the beginning, since template parms are listed
378 push_inline_template_parms_recursive (tree parmlist, int levels)
380 tree parms = TREE_VALUE (parmlist);
384 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
386 ++processing_template_decl;
387 current_template_parms
388 = tree_cons (size_int (processing_template_decl),
389 parms, current_template_parms);
390 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
392 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
394 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
396 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
398 if (parm == error_mark_node)
401 gcc_assert (DECL_P (parm));
403 switch (TREE_CODE (parm))
412 /* Make a CONST_DECL as is done in process_template_parm.
413 It is ugly that we recreate this here; the original
414 version built in process_template_parm is no longer
416 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
417 CONST_DECL, DECL_NAME (parm),
419 DECL_ARTIFICIAL (decl) = 1;
420 TREE_CONSTANT (decl) = 1;
421 TREE_READONLY (decl) = 1;
422 DECL_INITIAL (decl) = DECL_INITIAL (parm);
423 SET_DECL_TEMPLATE_PARM_P (decl);
434 /* Restore the template parameter context for a member template or
435 a friend template defined in a class definition. */
438 maybe_begin_member_template_processing (tree decl)
443 if (inline_needs_template_parms (decl))
445 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
446 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
448 if (DECL_TEMPLATE_SPECIALIZATION (decl))
451 parms = TREE_CHAIN (parms);
454 push_inline_template_parms_recursive (parms, levels);
457 /* Remember how many levels of template parameters we pushed so that
458 we can pop them later. */
459 VEC_safe_push (int, heap, inline_parm_levels, levels);
462 /* Undo the effects of maybe_begin_member_template_processing. */
465 maybe_end_member_template_processing (void)
470 if (VEC_length (int, inline_parm_levels) == 0)
473 last = VEC_pop (int, inline_parm_levels);
474 for (i = 0; i < last; ++i)
476 --processing_template_decl;
477 current_template_parms = TREE_CHAIN (current_template_parms);
482 /* Return a new template argument vector which contains all of ARGS,
483 but has as its innermost set of arguments the EXTRA_ARGS. */
486 add_to_template_args (tree args, tree extra_args)
493 if (args == NULL_TREE)
496 extra_depth = TMPL_ARGS_DEPTH (extra_args);
497 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
499 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
500 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
502 for (j = 1; j <= extra_depth; ++j, ++i)
503 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
508 /* Like add_to_template_args, but only the outermost ARGS are added to
509 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
510 (EXTRA_ARGS) levels are added. This function is used to combine
511 the template arguments from a partial instantiation with the
512 template arguments used to attain the full instantiation from the
513 partial instantiation. */
516 add_outermost_template_args (tree args, tree extra_args)
520 /* If there are more levels of EXTRA_ARGS than there are ARGS,
521 something very fishy is going on. */
522 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
524 /* If *all* the new arguments will be the EXTRA_ARGS, just return
526 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
529 /* For the moment, we make ARGS look like it contains fewer levels. */
530 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
532 new_args = add_to_template_args (args, extra_args);
534 /* Now, we restore ARGS to its full dimensions. */
535 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
540 /* Return the N levels of innermost template arguments from the ARGS. */
543 get_innermost_template_args (tree args, int n)
551 /* If N is 1, just return the innermost set of template arguments. */
553 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
555 /* If we're not removing anything, just return the arguments we were
557 extra_levels = TMPL_ARGS_DEPTH (args) - n;
558 gcc_assert (extra_levels >= 0);
559 if (extra_levels == 0)
562 /* Make a new set of arguments, not containing the outer arguments. */
563 new_args = make_tree_vec (n);
564 for (i = 1; i <= n; ++i)
565 SET_TMPL_ARGS_LEVEL (new_args, i,
566 TMPL_ARGS_LEVEL (args, i + extra_levels));
571 /* The inverse of get_innermost_template_args: Return all but the innermost
572 EXTRA_LEVELS levels of template arguments from the ARGS. */
575 strip_innermost_template_args (tree args, int extra_levels)
578 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
583 /* If N is 1, just return the outermost set of template arguments. */
585 return TMPL_ARGS_LEVEL (args, 1);
587 /* If we're not removing anything, just return the arguments we were
589 gcc_assert (extra_levels >= 0);
590 if (extra_levels == 0)
593 /* Make a new set of arguments, not containing the inner arguments. */
594 new_args = make_tree_vec (n);
595 for (i = 1; i <= n; ++i)
596 SET_TMPL_ARGS_LEVEL (new_args, i,
597 TMPL_ARGS_LEVEL (args, i));
602 /* We've got a template header coming up; push to a new level for storing
606 begin_template_parm_list (void)
608 /* We use a non-tag-transparent scope here, which causes pushtag to
609 put tags in this scope, rather than in the enclosing class or
610 namespace scope. This is the right thing, since we want
611 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
612 global template class, push_template_decl handles putting the
613 TEMPLATE_DECL into top-level scope. For a nested template class,
616 template <class T> struct S1 {
617 template <class T> struct S2 {};
620 pushtag contains special code to call pushdecl_with_scope on the
621 TEMPLATE_DECL for S2. */
622 begin_scope (sk_template_parms, NULL);
623 ++processing_template_decl;
624 ++processing_template_parmlist;
625 note_template_header (0);
628 /* This routine is called when a specialization is declared. If it is
629 invalid to declare a specialization here, an error is reported and
630 false is returned, otherwise this routine will return true. */
633 check_specialization_scope (void)
635 tree scope = current_scope ();
639 An explicit specialization shall be declared in the namespace of
640 which the template is a member, or, for member templates, in the
641 namespace of which the enclosing class or enclosing class
642 template is a member. An explicit specialization of a member
643 function, member class or static data member of a class template
644 shall be declared in the namespace of which the class template
646 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
648 error ("explicit specialization in non-namespace scope %qD", scope);
654 In an explicit specialization declaration for a member of a class
655 template or a member template that appears in namespace scope,
656 the member template and some of its enclosing class templates may
657 remain unspecialized, except that the declaration shall not
658 explicitly specialize a class member template if its enclosing
659 class templates are not explicitly specialized as well. */
660 if (current_template_parms)
662 error ("enclosing class templates are not explicitly specialized");
669 /* We've just seen template <>. */
672 begin_specialization (void)
674 begin_scope (sk_template_spec, NULL);
675 note_template_header (1);
676 return check_specialization_scope ();
679 /* Called at then end of processing a declaration preceded by
683 end_specialization (void)
686 reset_specialization ();
689 /* Any template <>'s that we have seen thus far are not referring to a
690 function specialization. */
693 reset_specialization (void)
695 processing_specialization = 0;
696 template_header_count = 0;
699 /* We've just seen a template header. If SPECIALIZATION is nonzero,
700 it was of the form template <>. */
703 note_template_header (int specialization)
705 processing_specialization = specialization;
706 template_header_count++;
709 /* We're beginning an explicit instantiation. */
712 begin_explicit_instantiation (void)
714 gcc_assert (!processing_explicit_instantiation);
715 processing_explicit_instantiation = true;
720 end_explicit_instantiation (void)
722 gcc_assert (processing_explicit_instantiation);
723 processing_explicit_instantiation = false;
726 /* An explicit specialization or partial specialization TMPL is being
727 declared. Check that the namespace in which the specialization is
728 occurring is permissible. Returns false iff it is invalid to
729 specialize TMPL in the current namespace. */
732 check_specialization_namespace (tree tmpl)
734 tree tpl_ns = decl_namespace_context (tmpl);
738 An explicit specialization shall be declared in the namespace of
739 which the template is a member, or, for member templates, in the
740 namespace of which the enclosing class or enclosing class
741 template is a member. An explicit specialization of a member
742 function, member class or static data member of a class template
743 shall be declared in the namespace of which the class template is
745 if (current_scope() != DECL_CONTEXT (tmpl)
746 && !at_namespace_scope_p ())
748 error ("specialization of %qD must appear at namespace scope", tmpl);
751 if (is_associated_namespace (current_namespace, tpl_ns))
752 /* Same or super-using namespace. */
756 permerror (input_location, "specialization of %qD in different namespace", tmpl);
757 permerror (input_location, " from definition of %q+#D", tmpl);
762 /* SPEC is an explicit instantiation. Check that it is valid to
763 perform this explicit instantiation in the current namespace. */
766 check_explicit_instantiation_namespace (tree spec)
770 /* DR 275: An explicit instantiation shall appear in an enclosing
771 namespace of its template. */
772 ns = decl_namespace_context (spec);
773 if (!is_ancestor (current_namespace, ns))
774 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
775 "(which does not enclose namespace %qD)",
776 spec, current_namespace, ns);
779 /* The TYPE is being declared. If it is a template type, that means it
780 is a partial specialization. Do appropriate error-checking. */
783 maybe_process_partial_specialization (tree type)
787 if (type == error_mark_node)
788 return error_mark_node;
790 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
792 error ("name of class shadows template template parameter %qD",
794 return error_mark_node;
797 context = TYPE_CONTEXT (type);
799 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
801 /* This is for ordinary explicit specialization and partial
802 specialization of a template class such as:
804 template <> class C<int>;
808 template <class T> class C<T*>;
810 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
812 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
813 && !COMPLETE_TYPE_P (type))
815 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
816 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
817 if (processing_template_decl)
819 if (push_template_decl (TYPE_MAIN_DECL (type))
821 return error_mark_node;
824 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
825 error ("specialization of %qT after instantiation", type);
827 else if (CLASS_TYPE_P (type)
828 && !CLASSTYPE_USE_TEMPLATE (type)
829 && CLASSTYPE_TEMPLATE_INFO (type)
830 && context && CLASS_TYPE_P (context)
831 && CLASSTYPE_TEMPLATE_INFO (context))
833 /* This is for an explicit specialization of member class
834 template according to [temp.expl.spec/18]:
836 template <> template <class U> class C<int>::D;
838 The context `C<int>' must be an implicit instantiation.
839 Otherwise this is just a member class template declared
842 template <> class C<int> { template <class U> class D; };
843 template <> template <class U> class C<int>::D;
845 In the first case, `C<int>::D' is a specialization of `C<T>::D'
846 while in the second case, `C<int>::D' is a primary template
847 and `C<T>::D' may not exist. */
849 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
850 && !COMPLETE_TYPE_P (type))
853 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
855 if (current_namespace
856 != decl_namespace_context (tmpl))
858 permerror (input_location, "specializing %q#T in different namespace", type);
859 permerror (input_location, " from definition of %q+#D", tmpl);
862 /* Check for invalid specialization after instantiation:
864 template <> template <> class C<int>::D<int>;
865 template <> template <class U> class C<int>::D; */
867 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
868 t; t = TREE_CHAIN (t))
870 tree inst = TREE_VALUE (t);
871 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
873 /* We already have a full specialization of this partial
874 instantiation. Reassign it to the new member
875 specialization template. */
879 elt.tmpl = most_general_template (tmpl);
880 elt.args = CLASSTYPE_TI_ARGS (inst);
883 htab_remove_elt (type_specializations, &elt);
886 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
888 slot = (spec_entry **)
889 htab_find_slot (type_specializations, &elt, INSERT);
890 *slot = ggc_alloc_spec_entry ();
893 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
894 /* But if we've had an implicit instantiation, that's a
895 problem ([temp.expl.spec]/6). */
896 error ("specialization %qT after instantiation %qT",
900 /* Mark TYPE as a specialization. And as a result, we only
901 have one level of template argument for the innermost
903 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
904 CLASSTYPE_TI_ARGS (type)
905 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
908 else if (processing_specialization)
910 error ("explicit specialization of non-template %qT", type);
911 return error_mark_node;
917 /* Returns nonzero if we can optimize the retrieval of specializations
918 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
919 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
922 optimize_specialization_lookup_p (tree tmpl)
924 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
925 && DECL_CLASS_SCOPE_P (tmpl)
926 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
928 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
929 /* The optimized lookup depends on the fact that the
930 template arguments for the member function template apply
931 purely to the containing class, which is not true if the
932 containing class is an explicit or partial
934 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
935 && !DECL_MEMBER_TEMPLATE_P (tmpl)
936 && !DECL_CONV_FN_P (tmpl)
937 /* It is possible to have a template that is not a member
938 template and is not a member of a template class:
940 template <typename T>
941 struct S { friend A::f(); };
943 Here, the friend function is a template, but the context does
944 not have template information. The optimized lookup relies
945 on having ARGS be the template arguments for both the class
946 and the function template. */
947 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
950 /* Retrieve the specialization (in the sense of [temp.spec] - a
951 specialization is either an instantiation or an explicit
952 specialization) of TMPL for the given template ARGS. If there is
953 no such specialization, return NULL_TREE. The ARGS are a vector of
954 arguments, or a vector of vectors of arguments, in the case of
955 templates with more than one level of parameters.
957 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
958 then we search for a partial specialization matching ARGS. This
959 parameter is ignored if TMPL is not a class template. */
962 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
964 if (args == error_mark_node)
967 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
969 /* There should be as many levels of arguments as there are
970 levels of parameters. */
971 gcc_assert (TMPL_ARGS_DEPTH (args)
972 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
974 if (optimize_specialization_lookup_p (tmpl))
977 tree class_specialization;
978 VEC(tree,gc) *methods;
982 /* The template arguments actually apply to the containing
983 class. Find the class specialization with those
985 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
987 = retrieve_specialization (class_template, args, 0);
988 if (!class_specialization)
990 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
991 for the specialization. */
992 idx = class_method_index_for_fn (class_specialization, tmpl);
995 /* Iterate through the methods with the indicated name, looking
996 for the one that has an instance of TMPL. */
997 methods = CLASSTYPE_METHOD_VEC (class_specialization);
998 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1000 tree fn = OVL_CURRENT (fns);
1001 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1002 /* using-declarations can add base methods to the method vec,
1003 and we don't want those here. */
1004 && DECL_CONTEXT (fn) == class_specialization)
1013 htab_t specializations;
1017 elt.spec = NULL_TREE;
1019 if (DECL_CLASS_TEMPLATE_P (tmpl))
1020 specializations = type_specializations;
1022 specializations = decl_specializations;
1025 hash = hash_specialization (&elt);
1026 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1034 /* Like retrieve_specialization, but for local declarations. */
1037 retrieve_local_specialization (tree tmpl)
1041 if (local_specializations == NULL)
1044 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1045 htab_hash_pointer (tmpl));
1046 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1049 /* Returns nonzero iff DECL is a specialization of TMPL. */
1052 is_specialization_of (tree decl, tree tmpl)
1056 if (TREE_CODE (decl) == FUNCTION_DECL)
1060 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1066 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1068 for (t = TREE_TYPE (decl);
1070 t = CLASSTYPE_USE_TEMPLATE (t)
1071 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1072 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1079 /* Returns nonzero iff DECL is a specialization of friend declaration
1080 FRIEND_DECL according to [temp.friend]. */
1083 is_specialization_of_friend (tree decl, tree friend_decl)
1085 bool need_template = true;
1088 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1089 || TREE_CODE (decl) == TYPE_DECL);
1091 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1092 of a template class, we want to check if DECL is a specialization
1094 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1095 && DECL_TEMPLATE_INFO (friend_decl)
1096 && !DECL_USE_TEMPLATE (friend_decl))
1098 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1099 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1100 need_template = false;
1102 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1103 && !PRIMARY_TEMPLATE_P (friend_decl))
1104 need_template = false;
1106 /* There is nothing to do if this is not a template friend. */
1107 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1110 if (is_specialization_of (decl, friend_decl))
1114 A member of a class template may be declared to be a friend of a
1115 non-template class. In this case, the corresponding member of
1116 every specialization of the class template is a friend of the
1117 class granting friendship.
1119 For example, given a template friend declaration
1121 template <class T> friend void A<T>::f();
1123 the member function below is considered a friend
1125 template <> struct A<int> {
1129 For this type of template friend, TEMPLATE_DEPTH below will be
1130 nonzero. To determine if DECL is a friend of FRIEND, we first
1131 check if the enclosing class is a specialization of another. */
1133 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1135 && DECL_CLASS_SCOPE_P (decl)
1136 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1137 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1139 /* Next, we check the members themselves. In order to handle
1140 a few tricky cases, such as when FRIEND_DECL's are
1142 template <class T> friend void A<T>::g(T t);
1143 template <class T> template <T t> friend void A<T>::h();
1147 void A<int>::g(int);
1148 template <int> void A<int>::h();
1150 we need to figure out ARGS, the template arguments from
1151 the context of DECL. This is required for template substitution
1152 of `T' in the function parameter of `g' and template parameter
1153 of `h' in the above examples. Here ARGS corresponds to `int'. */
1155 tree context = DECL_CONTEXT (decl);
1156 tree args = NULL_TREE;
1157 int current_depth = 0;
1159 while (current_depth < template_depth)
1161 if (CLASSTYPE_TEMPLATE_INFO (context))
1163 if (current_depth == 0)
1164 args = TYPE_TI_ARGS (context);
1166 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1169 context = TYPE_CONTEXT (context);
1172 if (TREE_CODE (decl) == FUNCTION_DECL)
1177 tree friend_args_type;
1178 tree decl_args_type;
1180 /* Make sure that both DECL and FRIEND_DECL are templates or
1182 is_template = DECL_TEMPLATE_INFO (decl)
1183 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1184 if (need_template ^ is_template)
1186 else if (is_template)
1188 /* If both are templates, check template parameter list. */
1190 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1192 if (!comp_template_parms
1193 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1197 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1200 decl_type = TREE_TYPE (decl);
1202 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1203 tf_none, NULL_TREE);
1204 if (friend_type == error_mark_node)
1207 /* Check if return types match. */
1208 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1211 /* Check if function parameter types match, ignoring the
1212 `this' parameter. */
1213 friend_args_type = TYPE_ARG_TYPES (friend_type);
1214 decl_args_type = TYPE_ARG_TYPES (decl_type);
1215 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1216 friend_args_type = TREE_CHAIN (friend_args_type);
1217 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1218 decl_args_type = TREE_CHAIN (decl_args_type);
1220 return compparms (decl_args_type, friend_args_type);
1224 /* DECL is a TYPE_DECL */
1226 tree decl_type = TREE_TYPE (decl);
1228 /* Make sure that both DECL and FRIEND_DECL are templates or
1231 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1232 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1234 if (need_template ^ is_template)
1236 else if (is_template)
1239 /* If both are templates, check the name of the two
1240 TEMPLATE_DECL's first because is_friend didn't. */
1241 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1242 != DECL_NAME (friend_decl))
1245 /* Now check template parameter list. */
1247 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1249 return comp_template_parms
1250 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1254 return (DECL_NAME (decl)
1255 == DECL_NAME (friend_decl));
1261 /* Register the specialization SPEC as a specialization of TMPL with
1262 the indicated ARGS. IS_FRIEND indicates whether the specialization
1263 is actually just a friend declaration. Returns SPEC, or an
1264 equivalent prior declaration, if available. */
1267 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1271 spec_entry **slot = NULL;
1274 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1276 if (TREE_CODE (spec) == FUNCTION_DECL
1277 && uses_template_parms (DECL_TI_ARGS (spec)))
1278 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1279 register it; we want the corresponding TEMPLATE_DECL instead.
1280 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1281 the more obvious `uses_template_parms (spec)' to avoid problems
1282 with default function arguments. In particular, given
1283 something like this:
1285 template <class T> void f(T t1, T t = T())
1287 the default argument expression is not substituted for in an
1288 instantiation unless and until it is actually needed. */
1291 if (optimize_specialization_lookup_p (tmpl))
1292 /* We don't put these specializations in the hash table, but we might
1293 want to give an error about a mismatch. */
1294 fn = retrieve_specialization (tmpl, args, 0);
1302 hash = hash_specialization (&elt);
1304 slot = (spec_entry **)
1305 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1312 /* We can sometimes try to re-register a specialization that we've
1313 already got. In particular, regenerate_decl_from_template calls
1314 duplicate_decls which will update the specialization list. But,
1315 we'll still get called again here anyhow. It's more convenient
1316 to simply allow this than to try to prevent it. */
1319 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1321 if (DECL_TEMPLATE_INSTANTIATION (fn))
1323 if (DECL_ODR_USED (fn)
1324 || DECL_EXPLICIT_INSTANTIATION (fn))
1326 error ("specialization of %qD after instantiation",
1328 return error_mark_node;
1333 /* This situation should occur only if the first
1334 specialization is an implicit instantiation, the
1335 second is an explicit specialization, and the
1336 implicit instantiation has not yet been used. That
1337 situation can occur if we have implicitly
1338 instantiated a member function and then specialized
1341 We can also wind up here if a friend declaration that
1342 looked like an instantiation turns out to be a
1345 template <class T> void foo(T);
1346 class S { friend void foo<>(int) };
1347 template <> void foo(int);
1349 We transform the existing DECL in place so that any
1350 pointers to it become pointers to the updated
1353 If there was a definition for the template, but not
1354 for the specialization, we want this to look as if
1355 there were no definition, and vice versa. */
1356 DECL_INITIAL (fn) = NULL_TREE;
1357 duplicate_decls (spec, fn, is_friend);
1358 /* The call to duplicate_decls will have applied
1361 An explicit specialization of a function template
1362 is inline only if it is explicitly declared to be,
1363 and independently of whether its function template
1366 to the primary function; now copy the inline bits to
1367 the various clones. */
1368 FOR_EACH_CLONE (clone, fn)
1370 DECL_DECLARED_INLINE_P (clone)
1371 = DECL_DECLARED_INLINE_P (fn);
1372 DECL_SOURCE_LOCATION (clone)
1373 = DECL_SOURCE_LOCATION (fn);
1375 check_specialization_namespace (fn);
1380 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1382 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1383 /* Dup decl failed, but this is a new definition. Set the
1384 line number so any errors match this new
1386 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1392 return duplicate_decls (spec, fn, is_friend);
1394 /* A specialization must be declared in the same namespace as the
1395 template it is specializing. */
1396 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1397 && !check_specialization_namespace (tmpl))
1398 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1400 if (!optimize_specialization_lookup_p (tmpl))
1402 gcc_assert (tmpl && args && spec);
1403 *slot = ggc_alloc_spec_entry ();
1405 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1406 && PRIMARY_TEMPLATE_P (tmpl)
1407 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1408 /* TMPL is a forward declaration of a template function; keep a list
1409 of all specializations in case we need to reassign them to a friend
1410 template later in tsubst_friend_function. */
1411 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1412 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1418 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1419 TMPL and ARGS members, ignores SPEC. */
1422 eq_specializations (const void *p1, const void *p2)
1424 const spec_entry *e1 = (const spec_entry *)p1;
1425 const spec_entry *e2 = (const spec_entry *)p2;
1427 return (e1->tmpl == e2->tmpl
1428 && comp_template_args (e1->args, e2->args));
1431 /* Returns a hash for a template TMPL and template arguments ARGS. */
1434 hash_tmpl_and_args (tree tmpl, tree args)
1436 hashval_t val = DECL_UID (tmpl);
1437 return iterative_hash_template_arg (args, val);
1440 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1444 hash_specialization (const void *p)
1446 const spec_entry *e = (const spec_entry *)p;
1447 return hash_tmpl_and_args (e->tmpl, e->args);
1450 /* Recursively calculate a hash value for a template argument ARG, for use
1451 in the hash tables of template specializations. */
1454 iterative_hash_template_arg (tree arg, hashval_t val)
1456 unsigned HOST_WIDE_INT i;
1457 enum tree_code code;
1460 if (arg == NULL_TREE)
1461 return iterative_hash_object (arg, val);
1466 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1467 /* We can get one of these when re-hashing a previous entry in the middle
1468 of substituting into a pack expansion. Just look through it. */
1469 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1471 code = TREE_CODE (arg);
1472 tclass = TREE_CODE_CLASS (code);
1474 val = iterative_hash_object (code, val);
1481 case IDENTIFIER_NODE:
1482 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1486 int i, len = TREE_VEC_LENGTH (arg);
1487 for (i = 0; i < len; ++i)
1488 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1492 case TYPE_PACK_EXPANSION:
1493 case EXPR_PACK_EXPANSION:
1494 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1496 case TYPE_ARGUMENT_PACK:
1497 case NONTYPE_ARGUMENT_PACK:
1498 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1501 for (; arg; arg = TREE_CHAIN (arg))
1502 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1506 for (; arg; arg = OVL_CHAIN (arg))
1507 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1513 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1515 val = iterative_hash_template_arg (field, val);
1516 val = iterative_hash_template_arg (value, val);
1522 if (!DECL_ARTIFICIAL (arg))
1523 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1524 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1527 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1530 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1531 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1533 case TEMPLATE_PARM_INDEX:
1534 val = iterative_hash_template_arg
1535 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1536 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1537 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1540 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1541 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1542 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1545 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1547 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1551 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1552 code = TREE_CODE (TREE_OPERAND (arg, 1));
1553 val = iterative_hash_object (code, val);
1554 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1557 /* layout_type sets structural equality for arrays of
1558 incomplete type, so we can't rely on the canonical type
1560 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1561 return iterative_hash_template_arg (TYPE_DOMAIN (arg), val);
1564 /* A lambda can't appear in a template arg, but don't crash on
1566 gcc_assert (seen_error ());
1570 case STATIC_CAST_EXPR:
1571 case REINTERPRET_CAST_EXPR:
1572 case CONST_CAST_EXPR:
1573 case DYNAMIC_CAST_EXPR:
1575 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1576 /* Now hash operands as usual. */
1586 if (TYPE_CANONICAL (arg))
1587 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1589 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1590 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1591 /* Otherwise just compare the types during lookup. */
1594 case tcc_declaration:
1596 return iterative_hash_expr (arg, val);
1599 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1601 unsigned n = TREE_OPERAND_LENGTH (arg);
1602 for (i = 0; i < n; ++i)
1603 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1611 /* Unregister the specialization SPEC as a specialization of TMPL.
1612 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1613 if the SPEC was listed as a specialization of TMPL.
1615 Note that SPEC has been ggc_freed, so we can't look inside it. */
1618 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1623 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1624 elt.args = TI_ARGS (tinfo);
1625 elt.spec = NULL_TREE;
1627 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1630 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1631 gcc_assert (new_spec != NULL_TREE);
1632 (*slot)->spec = new_spec;
1639 /* Compare an entry in the local specializations hash table P1 (which
1640 is really a pointer to a TREE_LIST) with P2 (which is really a
1644 eq_local_specializations (const void *p1, const void *p2)
1646 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1649 /* Hash P1, an entry in the local specializations table. */
1652 hash_local_specialization (const void* p1)
1654 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1657 /* Like register_specialization, but for local declarations. We are
1658 registering SPEC, an instantiation of TMPL. */
1661 register_local_specialization (tree spec, tree tmpl)
1665 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1666 htab_hash_pointer (tmpl), INSERT);
1667 *slot = build_tree_list (spec, tmpl);
1670 /* TYPE is a class type. Returns true if TYPE is an explicitly
1671 specialized class. */
1674 explicit_class_specialization_p (tree type)
1676 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1678 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1681 /* Print the list of functions at FNS, going through all the overloads
1682 for each element of the list. Alternatively, FNS can not be a
1683 TREE_LIST, in which case it will be printed together with all the
1686 MORE and *STR should respectively be FALSE and NULL when the function
1687 is called from the outside. They are used internally on recursive
1688 calls. print_candidates manages the two parameters and leaves NULL
1689 in *STR when it ends. */
1692 print_candidates_1 (tree fns, bool more, const char **str)
1695 char *spaces = NULL;
1697 for (fn = fns; fn; fn = OVL_NEXT (fn))
1698 if (TREE_CODE (fn) == TREE_LIST)
1700 gcc_assert (!OVL_NEXT (fn) && !is_overloaded_fn (fn));
1701 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1702 print_candidates_1 (TREE_VALUE (fn2),
1703 TREE_CHAIN (fn2) || more, str);
1709 /* Pick the prefix string. */
1710 if (!more && !OVL_NEXT (fns))
1712 error ("candidate is: %+#D", OVL_CURRENT (fn));
1716 *str = _("candidates are:");
1717 spaces = get_spaces (*str);
1719 error ("%s %+#D", *str, OVL_CURRENT (fn));
1720 *str = spaces ? spaces : *str;
1730 /* Print the list of candidate FNS in an error message. */
1733 print_candidates (tree fns)
1735 const char *str = NULL;
1736 print_candidates_1 (fns, false, &str);
1737 gcc_assert (str == NULL);
1740 /* Returns the template (one of the functions given by TEMPLATE_ID)
1741 which can be specialized to match the indicated DECL with the
1742 explicit template args given in TEMPLATE_ID. The DECL may be
1743 NULL_TREE if none is available. In that case, the functions in
1744 TEMPLATE_ID are non-members.
1746 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1747 specialization of a member template.
1749 The TEMPLATE_COUNT is the number of references to qualifying
1750 template classes that appeared in the name of the function. See
1751 check_explicit_specialization for a more accurate description.
1753 TSK indicates what kind of template declaration (if any) is being
1754 declared. TSK_TEMPLATE indicates that the declaration given by
1755 DECL, though a FUNCTION_DECL, has template parameters, and is
1756 therefore a template function.
1758 The template args (those explicitly specified and those deduced)
1759 are output in a newly created vector *TARGS_OUT.
1761 If it is impossible to determine the result, an error message is
1762 issued. The error_mark_node is returned to indicate failure. */
1765 determine_specialization (tree template_id,
1768 int need_member_template,
1774 tree explicit_targs;
1775 tree candidates = NULL_TREE;
1776 /* A TREE_LIST of templates of which DECL may be a specialization.
1777 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1778 corresponding TREE_PURPOSE is the set of template arguments that,
1779 when used to instantiate the template, would produce a function
1780 with the signature of DECL. */
1781 tree templates = NULL_TREE;
1783 struct cp_binding_level *b;
1785 *targs_out = NULL_TREE;
1787 if (template_id == error_mark_node || decl == error_mark_node)
1788 return error_mark_node;
1790 fns = TREE_OPERAND (template_id, 0);
1791 explicit_targs = TREE_OPERAND (template_id, 1);
1793 if (fns == error_mark_node)
1794 return error_mark_node;
1796 /* Check for baselinks. */
1797 if (BASELINK_P (fns))
1798 fns = BASELINK_FUNCTIONS (fns);
1800 if (!is_overloaded_fn (fns))
1802 error ("%qD is not a function template", fns);
1803 return error_mark_node;
1806 /* Count the number of template headers specified for this
1809 for (b = current_binding_level;
1810 b->kind == sk_template_parms;
1814 for (; fns; fns = OVL_NEXT (fns))
1816 tree fn = OVL_CURRENT (fns);
1818 if (TREE_CODE (fn) == TEMPLATE_DECL)
1820 tree decl_arg_types;
1823 /* In case of explicit specialization, we need to check if
1824 the number of template headers appearing in the specialization
1825 is correct. This is usually done in check_explicit_specialization,
1826 but the check done there cannot be exhaustive when specializing
1827 member functions. Consider the following code:
1829 template <> void A<int>::f(int);
1830 template <> template <> void A<int>::f(int);
1832 Assuming that A<int> is not itself an explicit specialization
1833 already, the first line specializes "f" which is a non-template
1834 member function, whilst the second line specializes "f" which
1835 is a template member function. So both lines are syntactically
1836 correct, and check_explicit_specialization does not reject
1839 Here, we can do better, as we are matching the specialization
1840 against the declarations. We count the number of template
1841 headers, and we check if they match TEMPLATE_COUNT + 1
1842 (TEMPLATE_COUNT is the number of qualifying template classes,
1843 plus there must be another header for the member template
1846 Notice that if header_count is zero, this is not a
1847 specialization but rather a template instantiation, so there
1848 is no check we can perform here. */
1849 if (header_count && header_count != template_count + 1)
1852 /* Check that the number of template arguments at the
1853 innermost level for DECL is the same as for FN. */
1854 if (current_binding_level->kind == sk_template_parms
1855 && !current_binding_level->explicit_spec_p
1856 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1857 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1858 (current_template_parms))))
1861 /* DECL might be a specialization of FN. */
1862 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1863 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1865 /* For a non-static member function, we need to make sure
1866 that the const qualification is the same. Since
1867 get_bindings does not try to merge the "this" parameter,
1868 we must do the comparison explicitly. */
1869 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1870 && !same_type_p (TREE_VALUE (fn_arg_types),
1871 TREE_VALUE (decl_arg_types)))
1874 /* Skip the "this" parameter and, for constructors of
1875 classes with virtual bases, the VTT parameter. A
1876 full specialization of a constructor will have a VTT
1877 parameter, but a template never will. */
1879 = skip_artificial_parms_for (decl, decl_arg_types);
1881 = skip_artificial_parms_for (fn, fn_arg_types);
1883 /* Check that the number of function parameters matches.
1885 template <class T> void f(int i = 0);
1886 template <> void f<int>();
1887 The specialization f<int> is invalid but is not caught
1888 by get_bindings below. */
1889 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1892 /* Function templates cannot be specializations; there are
1893 no partial specializations of functions. Therefore, if
1894 the type of DECL does not match FN, there is no
1896 if (tsk == tsk_template)
1898 if (compparms (fn_arg_types, decl_arg_types))
1899 candidates = tree_cons (NULL_TREE, fn, candidates);
1903 /* See whether this function might be a specialization of this
1905 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1908 /* We cannot deduce template arguments that when used to
1909 specialize TMPL will produce DECL. */
1912 /* Save this template, and the arguments deduced. */
1913 templates = tree_cons (targs, fn, templates);
1915 else if (need_member_template)
1916 /* FN is an ordinary member function, and we need a
1917 specialization of a member template. */
1919 else if (TREE_CODE (fn) != FUNCTION_DECL)
1920 /* We can get IDENTIFIER_NODEs here in certain erroneous
1923 else if (!DECL_FUNCTION_MEMBER_P (fn))
1924 /* This is just an ordinary non-member function. Nothing can
1925 be a specialization of that. */
1927 else if (DECL_ARTIFICIAL (fn))
1928 /* Cannot specialize functions that are created implicitly. */
1932 tree decl_arg_types;
1934 /* This is an ordinary member function. However, since
1935 we're here, we can assume it's enclosing class is a
1936 template class. For example,
1938 template <typename T> struct S { void f(); };
1939 template <> void S<int>::f() {}
1941 Here, S<int>::f is a non-template, but S<int> is a
1942 template class. If FN has the same type as DECL, we
1943 might be in business. */
1945 if (!DECL_TEMPLATE_INFO (fn))
1946 /* Its enclosing class is an explicit specialization
1947 of a template class. This is not a candidate. */
1950 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1951 TREE_TYPE (TREE_TYPE (fn))))
1952 /* The return types differ. */
1955 /* Adjust the type of DECL in case FN is a static member. */
1956 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1957 if (DECL_STATIC_FUNCTION_P (fn)
1958 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1959 decl_arg_types = TREE_CHAIN (decl_arg_types);
1961 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1964 candidates = tree_cons (NULL_TREE, fn, candidates);
1968 if (templates && TREE_CHAIN (templates))
1974 It is possible for a specialization with a given function
1975 signature to be instantiated from more than one function
1976 template. In such cases, explicit specification of the
1977 template arguments must be used to uniquely identify the
1978 function template specialization being specialized.
1980 Note that here, there's no suggestion that we're supposed to
1981 determine which of the candidate templates is most
1982 specialized. However, we, also have:
1986 Partial ordering of overloaded function template
1987 declarations is used in the following contexts to select
1988 the function template to which a function template
1989 specialization refers:
1991 -- when an explicit specialization refers to a function
1994 So, we do use the partial ordering rules, at least for now.
1995 This extension can only serve to make invalid programs valid,
1996 so it's safe. And, there is strong anecdotal evidence that
1997 the committee intended the partial ordering rules to apply;
1998 the EDG front end has that behavior, and John Spicer claims
1999 that the committee simply forgot to delete the wording in
2000 [temp.expl.spec]. */
2001 tree tmpl = most_specialized_instantiation (templates);
2002 if (tmpl != error_mark_node)
2005 TREE_CHAIN (templates) = NULL_TREE;
2009 if (templates == NULL_TREE && candidates == NULL_TREE)
2011 error ("template-id %qD for %q+D does not match any template "
2012 "declaration", template_id, decl);
2013 if (header_count && header_count != template_count + 1)
2014 inform (input_location, "saw %d %<template<>%>, need %d for "
2015 "specializing a member function template",
2016 header_count, template_count + 1);
2017 return error_mark_node;
2019 else if ((templates && TREE_CHAIN (templates))
2020 || (candidates && TREE_CHAIN (candidates))
2021 || (templates && candidates))
2023 error ("ambiguous template specialization %qD for %q+D",
2025 candidates = chainon (candidates, templates);
2026 print_candidates (candidates);
2027 return error_mark_node;
2030 /* We have one, and exactly one, match. */
2033 tree fn = TREE_VALUE (candidates);
2034 *targs_out = copy_node (DECL_TI_ARGS (fn));
2035 /* DECL is a re-declaration or partial instantiation of a template
2037 if (TREE_CODE (fn) == TEMPLATE_DECL)
2039 /* It was a specialization of an ordinary member function in a
2041 return DECL_TI_TEMPLATE (fn);
2044 /* It was a specialization of a template. */
2045 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2046 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2048 *targs_out = copy_node (targs);
2049 SET_TMPL_ARGS_LEVEL (*targs_out,
2050 TMPL_ARGS_DEPTH (*targs_out),
2051 TREE_PURPOSE (templates));
2054 *targs_out = TREE_PURPOSE (templates);
2055 return TREE_VALUE (templates);
2058 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2059 but with the default argument values filled in from those in the
2063 copy_default_args_to_explicit_spec_1 (tree spec_types,
2066 tree new_spec_types;
2071 if (spec_types == void_list_node)
2072 return void_list_node;
2074 /* Substitute into the rest of the list. */
2076 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2077 TREE_CHAIN (tmpl_types));
2079 /* Add the default argument for this parameter. */
2080 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2081 TREE_VALUE (spec_types),
2085 /* DECL is an explicit specialization. Replicate default arguments
2086 from the template it specializes. (That way, code like:
2088 template <class T> void f(T = 3);
2089 template <> void f(double);
2092 works, as required.) An alternative approach would be to look up
2093 the correct default arguments at the call-site, but this approach
2094 is consistent with how implicit instantiations are handled. */
2097 copy_default_args_to_explicit_spec (tree decl)
2102 tree new_spec_types;
2106 tree object_type = NULL_TREE;
2107 tree in_charge = NULL_TREE;
2108 tree vtt = NULL_TREE;
2110 /* See if there's anything we need to do. */
2111 tmpl = DECL_TI_TEMPLATE (decl);
2112 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2113 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2114 if (TREE_PURPOSE (t))
2119 old_type = TREE_TYPE (decl);
2120 spec_types = TYPE_ARG_TYPES (old_type);
2122 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2124 /* Remove the this pointer, but remember the object's type for
2126 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2127 spec_types = TREE_CHAIN (spec_types);
2128 tmpl_types = TREE_CHAIN (tmpl_types);
2130 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2132 /* DECL may contain more parameters than TMPL due to the extra
2133 in-charge parameter in constructors and destructors. */
2134 in_charge = spec_types;
2135 spec_types = TREE_CHAIN (spec_types);
2137 if (DECL_HAS_VTT_PARM_P (decl))
2140 spec_types = TREE_CHAIN (spec_types);
2144 /* Compute the merged default arguments. */
2146 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2148 /* Compute the new FUNCTION_TYPE. */
2152 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2157 /* Put the in-charge parameter back. */
2158 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2159 TREE_VALUE (in_charge),
2162 new_type = build_method_type_directly (object_type,
2163 TREE_TYPE (old_type),
2167 new_type = build_function_type (TREE_TYPE (old_type),
2169 new_type = cp_build_type_attribute_variant (new_type,
2170 TYPE_ATTRIBUTES (old_type));
2171 new_type = build_exception_variant (new_type,
2172 TYPE_RAISES_EXCEPTIONS (old_type));
2173 TREE_TYPE (decl) = new_type;
2176 /* Check to see if the function just declared, as indicated in
2177 DECLARATOR, and in DECL, is a specialization of a function
2178 template. We may also discover that the declaration is an explicit
2179 instantiation at this point.
2181 Returns DECL, or an equivalent declaration that should be used
2182 instead if all goes well. Issues an error message if something is
2183 amiss. Returns error_mark_node if the error is not easily
2186 FLAGS is a bitmask consisting of the following flags:
2188 2: The function has a definition.
2189 4: The function is a friend.
2191 The TEMPLATE_COUNT is the number of references to qualifying
2192 template classes that appeared in the name of the function. For
2195 template <class T> struct S { void f(); };
2198 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2199 classes are not counted in the TEMPLATE_COUNT, so that in
2201 template <class T> struct S {};
2202 template <> struct S<int> { void f(); }
2203 template <> void S<int>::f();
2205 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2206 invalid; there should be no template <>.)
2208 If the function is a specialization, it is marked as such via
2209 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2210 is set up correctly, and it is added to the list of specializations
2211 for that template. */
2214 check_explicit_specialization (tree declarator,
2219 int have_def = flags & 2;
2220 int is_friend = flags & 4;
2221 int specialization = 0;
2222 int explicit_instantiation = 0;
2223 int member_specialization = 0;
2224 tree ctype = DECL_CLASS_CONTEXT (decl);
2225 tree dname = DECL_NAME (decl);
2230 if (!processing_specialization)
2233 tsk = tsk_excessive_parms;
2236 tsk = current_tmpl_spec_kind (template_count);
2241 if (processing_specialization)
2244 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2246 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2249 /* This could be something like:
2251 template <class T> void f(T);
2252 class S { friend void f<>(int); } */
2256 /* This case handles bogus declarations like template <>
2257 template <class T> void f<int>(); */
2259 error ("template-id %qD in declaration of primary template",
2266 case tsk_invalid_member_spec:
2267 /* The error has already been reported in
2268 check_specialization_scope. */
2269 return error_mark_node;
2271 case tsk_invalid_expl_inst:
2272 error ("template parameter list used in explicit instantiation");
2278 error ("definition provided for explicit instantiation");
2280 explicit_instantiation = 1;
2283 case tsk_excessive_parms:
2284 case tsk_insufficient_parms:
2285 if (tsk == tsk_excessive_parms)
2286 error ("too many template parameter lists in declaration of %qD",
2288 else if (template_header_count)
2289 error("too few template parameter lists in declaration of %qD", decl);
2291 error("explicit specialization of %qD must be introduced by "
2292 "%<template <>%>", decl);
2296 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2298 member_specialization = 1;
2304 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2306 /* This case handles bogus declarations like template <>
2307 template <class T> void f<int>(); */
2309 if (uses_template_parms (declarator))
2310 error ("function template partial specialization %qD "
2311 "is not allowed", declarator);
2313 error ("template-id %qD in declaration of primary template",
2318 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2319 /* This is a specialization of a member template, without
2320 specialization the containing class. Something like:
2322 template <class T> struct S {
2323 template <class U> void f (U);
2325 template <> template <class U> void S<int>::f(U) {}
2327 That's a specialization -- but of the entire template. */
2335 if (specialization || member_specialization)
2337 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2338 for (; t; t = TREE_CHAIN (t))
2339 if (TREE_PURPOSE (t))
2341 permerror (input_location,
2342 "default argument specified in explicit specialization");
2347 if (specialization || member_specialization || explicit_instantiation)
2349 tree tmpl = NULL_TREE;
2350 tree targs = NULL_TREE;
2352 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2353 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2357 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2362 /* If there is no class context, the explicit instantiation
2363 must be at namespace scope. */
2364 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2366 /* Find the namespace binding, using the declaration
2368 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2370 if (fns == error_mark_node || !is_overloaded_fn (fns))
2372 error ("%qD is not a template function", dname);
2373 fns = error_mark_node;
2377 tree fn = OVL_CURRENT (fns);
2378 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2379 CP_DECL_CONTEXT (fn)))
2380 error ("%qD is not declared in %qD",
2381 decl, current_namespace);
2385 declarator = lookup_template_function (fns, NULL_TREE);
2388 if (declarator == error_mark_node)
2389 return error_mark_node;
2391 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2393 if (!explicit_instantiation)
2394 /* A specialization in class scope. This is invalid,
2395 but the error will already have been flagged by
2396 check_specialization_scope. */
2397 return error_mark_node;
2400 /* It's not valid to write an explicit instantiation in
2403 class C { template void f(); }
2405 This case is caught by the parser. However, on
2408 template class C { void f(); };
2410 (which is invalid) we can get here. The error will be
2417 else if (ctype != NULL_TREE
2418 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2421 /* Find the list of functions in ctype that have the same
2422 name as the declared function. */
2423 tree name = TREE_OPERAND (declarator, 0);
2424 tree fns = NULL_TREE;
2427 if (constructor_name_p (name, ctype))
2429 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2431 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2432 : !CLASSTYPE_DESTRUCTORS (ctype))
2434 /* From [temp.expl.spec]:
2436 If such an explicit specialization for the member
2437 of a class template names an implicitly-declared
2438 special member function (clause _special_), the
2439 program is ill-formed.
2441 Similar language is found in [temp.explicit]. */
2442 error ("specialization of implicitly-declared special member function");
2443 return error_mark_node;
2446 name = is_constructor ? ctor_identifier : dtor_identifier;
2449 if (!DECL_CONV_FN_P (decl))
2451 idx = lookup_fnfields_1 (ctype, name);
2453 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2457 VEC(tree,gc) *methods;
2460 /* For a type-conversion operator, we cannot do a
2461 name-based lookup. We might be looking for `operator
2462 int' which will be a specialization of `operator T'.
2463 So, we find *all* the conversion operators, and then
2464 select from them. */
2467 methods = CLASSTYPE_METHOD_VEC (ctype);
2469 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2470 VEC_iterate (tree, methods, idx, ovl);
2473 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2474 /* There are no more conversion functions. */
2477 /* Glue all these conversion functions together
2478 with those we already have. */
2479 for (; ovl; ovl = OVL_NEXT (ovl))
2480 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2484 if (fns == NULL_TREE)
2486 error ("no member function %qD declared in %qT", name, ctype);
2487 return error_mark_node;
2490 TREE_OPERAND (declarator, 0) = fns;
2493 /* Figure out what exactly is being specialized at this point.
2494 Note that for an explicit instantiation, even one for a
2495 member function, we cannot tell apriori whether the
2496 instantiation is for a member template, or just a member
2497 function of a template class. Even if a member template is
2498 being instantiated, the member template arguments may be
2499 elided if they can be deduced from the rest of the
2501 tmpl = determine_specialization (declarator, decl,
2503 member_specialization,
2507 if (!tmpl || tmpl == error_mark_node)
2508 /* We couldn't figure out what this declaration was
2510 return error_mark_node;
2513 tree gen_tmpl = most_general_template (tmpl);
2515 if (explicit_instantiation)
2517 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2518 is done by do_decl_instantiation later. */
2520 int arg_depth = TMPL_ARGS_DEPTH (targs);
2521 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2523 if (arg_depth > parm_depth)
2525 /* If TMPL is not the most general template (for
2526 example, if TMPL is a friend template that is
2527 injected into namespace scope), then there will
2528 be too many levels of TARGS. Remove some of them
2533 new_targs = make_tree_vec (parm_depth);
2534 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2535 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2536 = TREE_VEC_ELT (targs, i);
2540 return instantiate_template (tmpl, targs, tf_error);
2543 /* If we thought that the DECL was a member function, but it
2544 turns out to be specializing a static member function,
2545 make DECL a static member function as well. */
2546 if (DECL_STATIC_FUNCTION_P (tmpl)
2547 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2548 revert_static_member_fn (decl);
2550 /* If this is a specialization of a member template of a
2551 template class, we want to return the TEMPLATE_DECL, not
2552 the specialization of it. */
2553 if (tsk == tsk_template)
2555 tree result = DECL_TEMPLATE_RESULT (tmpl);
2556 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2557 DECL_INITIAL (result) = NULL_TREE;
2561 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2562 DECL_SOURCE_LOCATION (result)
2563 = DECL_SOURCE_LOCATION (decl);
2564 /* We want to use the argument list specified in the
2565 definition, not in the original declaration. */
2566 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2567 for (parm = DECL_ARGUMENTS (result); parm;
2568 parm = DECL_CHAIN (parm))
2569 DECL_CONTEXT (parm) = result;
2571 return register_specialization (tmpl, gen_tmpl, targs,
2575 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2576 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2578 /* Inherit default function arguments from the template
2579 DECL is specializing. */
2580 copy_default_args_to_explicit_spec (decl);
2582 /* This specialization has the same protection as the
2583 template it specializes. */
2584 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2585 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2587 /* 7.1.1-1 [dcl.stc]
2589 A storage-class-specifier shall not be specified in an
2590 explicit specialization...
2592 The parser rejects these, so unless action is taken here,
2593 explicit function specializations will always appear with
2596 The action recommended by the C++ CWG in response to C++
2597 defect report 605 is to make the storage class and linkage
2598 of the explicit specialization match the templated function:
2600 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2602 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2604 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2605 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2607 /* This specialization has the same linkage and visibility as
2608 the function template it specializes. */
2609 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2610 if (! TREE_PUBLIC (decl))
2612 DECL_INTERFACE_KNOWN (decl) = 1;
2613 DECL_NOT_REALLY_EXTERN (decl) = 1;
2615 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2616 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2618 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2619 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2623 /* If DECL is a friend declaration, declared using an
2624 unqualified name, the namespace associated with DECL may
2625 have been set incorrectly. For example, in:
2627 template <typename T> void f(T);
2629 struct S { friend void f<int>(int); }
2632 we will have set the DECL_CONTEXT for the friend
2633 declaration to N, rather than to the global namespace. */
2634 if (DECL_NAMESPACE_SCOPE_P (decl))
2635 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2637 if (is_friend && !have_def)
2638 /* This is not really a declaration of a specialization.
2639 It's just the name of an instantiation. But, it's not
2640 a request for an instantiation, either. */
2641 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2642 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2643 /* This is indeed a specialization. In case of constructors
2644 and destructors, we need in-charge and not-in-charge
2645 versions in V3 ABI. */
2646 clone_function_decl (decl, /*update_method_vec_p=*/0);
2648 /* Register this specialization so that we can find it
2650 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2657 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2658 parameters. These are represented in the same format used for
2659 DECL_TEMPLATE_PARMS. */
2662 comp_template_parms (const_tree parms1, const_tree parms2)
2667 if (parms1 == parms2)
2670 for (p1 = parms1, p2 = parms2;
2671 p1 != NULL_TREE && p2 != NULL_TREE;
2672 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2674 tree t1 = TREE_VALUE (p1);
2675 tree t2 = TREE_VALUE (p2);
2678 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2679 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2681 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2684 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2686 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2687 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2689 /* If either of the template parameters are invalid, assume
2690 they match for the sake of error recovery. */
2691 if (parm1 == error_mark_node || parm2 == error_mark_node)
2694 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2697 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2698 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2699 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2701 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2706 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2707 /* One set of parameters has more parameters lists than the
2714 /* Determine whether PARM is a parameter pack. */
2717 template_parameter_pack_p (const_tree parm)
2719 /* Determine if we have a non-type template parameter pack. */
2720 if (TREE_CODE (parm) == PARM_DECL)
2721 return (DECL_TEMPLATE_PARM_P (parm)
2722 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2724 /* If this is a list of template parameters, we could get a
2725 TYPE_DECL or a TEMPLATE_DECL. */
2726 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2727 parm = TREE_TYPE (parm);
2729 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2730 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2731 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2734 /* Determine if T is a function parameter pack. */
2737 function_parameter_pack_p (const_tree t)
2739 if (t && TREE_CODE (t) == PARM_DECL)
2740 return FUNCTION_PARAMETER_PACK_P (t);
2744 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2745 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2748 get_function_template_decl (const_tree primary_func_tmpl_inst)
2750 if (! primary_func_tmpl_inst
2751 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2752 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2755 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2758 /* Return true iff the function parameter PARAM_DECL was expanded
2759 from the function parameter pack PACK. */
2762 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2764 if (DECL_ARTIFICIAL (param_decl)
2765 || !function_parameter_pack_p (pack))
2768 /* The parameter pack and its pack arguments have the same
2770 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2773 /* Determine whether ARGS describes a variadic template args list,
2774 i.e., one that is terminated by a template argument pack. */
2777 template_args_variadic_p (tree args)
2782 if (args == NULL_TREE)
2785 args = INNERMOST_TEMPLATE_ARGS (args);
2786 nargs = TREE_VEC_LENGTH (args);
2791 last_parm = TREE_VEC_ELT (args, nargs - 1);
2793 return ARGUMENT_PACK_P (last_parm);
2796 /* Generate a new name for the parameter pack name NAME (an
2797 IDENTIFIER_NODE) that incorporates its */
2800 make_ith_pack_parameter_name (tree name, int i)
2802 /* Munge the name to include the parameter index. */
2803 #define NUMBUF_LEN 128
2804 char numbuf[NUMBUF_LEN];
2808 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2809 newname_len = IDENTIFIER_LENGTH (name)
2810 + strlen (numbuf) + 2;
2811 newname = (char*)alloca (newname_len);
2812 snprintf (newname, newname_len,
2813 "%s#%i", IDENTIFIER_POINTER (name), i);
2814 return get_identifier (newname);
2817 /* Return true if T is a primary function
2818 or class template instantiation. */
2821 primary_template_instantiation_p (const_tree t)
2826 if (TREE_CODE (t) == FUNCTION_DECL)
2827 return DECL_LANG_SPECIFIC (t)
2828 && DECL_TEMPLATE_INSTANTIATION (t)
2829 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2830 else if (CLASS_TYPE_P (t))
2831 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2832 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2836 /* Return true if PARM is a template template parameter. */
2839 template_template_parameter_p (const_tree parm)
2841 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2844 /* Return the template parameters of T if T is a
2845 primary template instantiation, NULL otherwise. */
2848 get_primary_template_innermost_parameters (const_tree t)
2850 tree parms = NULL, template_info = NULL;
2852 if ((template_info = get_template_info (t))
2853 && primary_template_instantiation_p (t))
2854 parms = INNERMOST_TEMPLATE_PARMS
2855 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2860 /* Return the template parameters of the LEVELth level from the full list
2861 of template parameters PARMS. */
2864 get_template_parms_at_level (tree parms, int level)
2868 || TREE_CODE (parms) != TREE_LIST
2869 || level > TMPL_PARMS_DEPTH (parms))
2872 for (p = parms; p; p = TREE_CHAIN (p))
2873 if (TMPL_PARMS_DEPTH (p) == level)
2879 /* Returns the template arguments of T if T is a template instantiation,
2883 get_template_innermost_arguments (const_tree t)
2885 tree args = NULL, template_info = NULL;
2887 if ((template_info = get_template_info (t))
2888 && TI_ARGS (template_info))
2889 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2894 /* Return the argument pack elements of T if T is a template argument pack,
2898 get_template_argument_pack_elems (const_tree t)
2900 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2901 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2904 return ARGUMENT_PACK_ARGS (t);
2907 /* Structure used to track the progress of find_parameter_packs_r. */
2908 struct find_parameter_pack_data
2910 /* TREE_LIST that will contain all of the parameter packs found by
2912 tree* parameter_packs;
2914 /* Set of AST nodes that have been visited by the traversal. */
2915 struct pointer_set_t *visited;
2918 /* Identifies all of the argument packs that occur in a template
2919 argument and appends them to the TREE_LIST inside DATA, which is a
2920 find_parameter_pack_data structure. This is a subroutine of
2921 make_pack_expansion and uses_parameter_packs. */
2923 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2926 struct find_parameter_pack_data* ppd =
2927 (struct find_parameter_pack_data*)data;
2928 bool parameter_pack_p = false;
2930 /* Identify whether this is a parameter pack or not. */
2931 switch (TREE_CODE (t))
2933 case TEMPLATE_PARM_INDEX:
2934 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2935 parameter_pack_p = true;
2938 case TEMPLATE_TYPE_PARM:
2939 case TEMPLATE_TEMPLATE_PARM:
2940 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2941 parameter_pack_p = true;
2945 if (FUNCTION_PARAMETER_PACK_P (t))
2947 /* We don't want to walk into the type of a PARM_DECL,
2948 because we don't want to see the type parameter pack. */
2950 parameter_pack_p = true;
2955 /* Not a parameter pack. */
2959 if (parameter_pack_p)
2961 /* Add this parameter pack to the list. */
2962 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2966 cp_walk_tree (&TYPE_CONTEXT (t),
2967 &find_parameter_packs_r, ppd, ppd->visited);
2969 /* This switch statement will return immediately if we don't find a
2971 switch (TREE_CODE (t))
2973 case TEMPLATE_PARM_INDEX:
2976 case BOUND_TEMPLATE_TEMPLATE_PARM:
2977 /* Check the template itself. */
2978 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2979 &find_parameter_packs_r, ppd, ppd->visited);
2980 /* Check the template arguments. */
2981 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2986 case TEMPLATE_TYPE_PARM:
2987 case TEMPLATE_TEMPLATE_PARM:
2994 if (TYPE_PTRMEMFUNC_P (t))
3000 if (TYPE_TEMPLATE_INFO (t))
3001 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3002 &find_parameter_packs_r, ppd, ppd->visited);
3008 cp_walk_tree (&TREE_TYPE (t),
3009 &find_parameter_packs_r, ppd, ppd->visited);
3013 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3018 case TYPE_PACK_EXPANSION:
3019 case EXPR_PACK_EXPANSION:
3024 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3029 case IDENTIFIER_NODE:
3030 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3042 /* Determines if the expression or type T uses any parameter packs. */
3044 uses_parameter_packs (tree t)
3046 tree parameter_packs = NULL_TREE;
3047 struct find_parameter_pack_data ppd;
3048 ppd.parameter_packs = ¶meter_packs;
3049 ppd.visited = pointer_set_create ();
3050 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3051 pointer_set_destroy (ppd.visited);
3052 return parameter_packs != NULL_TREE;
3055 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3056 representation a base-class initializer into a parameter pack
3057 expansion. If all goes well, the resulting node will be an
3058 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3061 make_pack_expansion (tree arg)
3064 tree parameter_packs = NULL_TREE;
3065 bool for_types = false;
3066 struct find_parameter_pack_data ppd;
3068 if (!arg || arg == error_mark_node)
3071 if (TREE_CODE (arg) == TREE_LIST)
3073 /* The only time we will see a TREE_LIST here is for a base
3074 class initializer. In this case, the TREE_PURPOSE will be a
3075 _TYPE node (representing the base class expansion we're
3076 initializing) and the TREE_VALUE will be a TREE_LIST
3077 containing the initialization arguments.
3079 The resulting expansion looks somewhat different from most
3080 expansions. Rather than returning just one _EXPANSION, we
3081 return a TREE_LIST whose TREE_PURPOSE is a
3082 TYPE_PACK_EXPANSION containing the bases that will be
3083 initialized. The TREE_VALUE will be identical to the
3084 original TREE_VALUE, which is a list of arguments that will
3085 be passed to each base. We do not introduce any new pack
3086 expansion nodes into the TREE_VALUE (although it is possible
3087 that some already exist), because the TREE_PURPOSE and
3088 TREE_VALUE all need to be expanded together with the same
3089 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3090 resulting TREE_PURPOSE will mention the parameter packs in
3091 both the bases and the arguments to the bases. */
3094 tree parameter_packs = NULL_TREE;
3096 /* Determine which parameter packs will be used by the base
3098 ppd.visited = pointer_set_create ();
3099 ppd.parameter_packs = ¶meter_packs;
3100 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3103 if (parameter_packs == NULL_TREE)
3105 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3106 pointer_set_destroy (ppd.visited);
3107 return error_mark_node;
3110 if (TREE_VALUE (arg) != void_type_node)
3112 /* Collect the sets of parameter packs used in each of the
3113 initialization arguments. */
3114 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3116 /* Determine which parameter packs will be expanded in this
3118 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3123 pointer_set_destroy (ppd.visited);
3125 /* Create the pack expansion type for the base type. */
3126 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3127 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3128 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3130 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3131 they will rarely be compared to anything. */
3132 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3134 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3137 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3140 /* Build the PACK_EXPANSION_* node. */
3142 ? cxx_make_type (TYPE_PACK_EXPANSION)
3143 : make_node (EXPR_PACK_EXPANSION);
3144 SET_PACK_EXPANSION_PATTERN (result, arg);
3145 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3147 /* Propagate type and const-expression information. */
3148 TREE_TYPE (result) = TREE_TYPE (arg);
3149 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3152 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3153 they will rarely be compared to anything. */
3154 SET_TYPE_STRUCTURAL_EQUALITY (result);
3156 /* Determine which parameter packs will be expanded. */
3157 ppd.parameter_packs = ¶meter_packs;
3158 ppd.visited = pointer_set_create ();
3159 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3160 pointer_set_destroy (ppd.visited);
3162 /* Make sure we found some parameter packs. */
3163 if (parameter_packs == NULL_TREE)
3166 error ("expansion pattern %<%T%> contains no argument packs", arg);
3168 error ("expansion pattern %<%E%> contains no argument packs", arg);
3169 return error_mark_node;
3171 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3176 /* Checks T for any "bare" parameter packs, which have not yet been
3177 expanded, and issues an error if any are found. This operation can
3178 only be done on full expressions or types (e.g., an expression
3179 statement, "if" condition, etc.), because we could have expressions like:
3181 foo(f(g(h(args)))...)
3183 where "args" is a parameter pack. check_for_bare_parameter_packs
3184 should not be called for the subexpressions args, h(args),
3185 g(h(args)), or f(g(h(args))), because we would produce erroneous
3188 Returns TRUE and emits an error if there were bare parameter packs,
3189 returns FALSE otherwise. */
3191 check_for_bare_parameter_packs (tree t)
3193 tree parameter_packs = NULL_TREE;
3194 struct find_parameter_pack_data ppd;
3196 if (!processing_template_decl || !t || t == error_mark_node)
3199 if (TREE_CODE (t) == TYPE_DECL)
3202 ppd.parameter_packs = ¶meter_packs;
3203 ppd.visited = pointer_set_create ();
3204 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3205 pointer_set_destroy (ppd.visited);
3207 if (parameter_packs)
3209 error ("parameter packs not expanded with %<...%>:");
3210 while (parameter_packs)
3212 tree pack = TREE_VALUE (parameter_packs);
3213 tree name = NULL_TREE;
3215 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3216 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3217 name = TYPE_NAME (pack);
3218 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3219 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3221 name = DECL_NAME (pack);
3224 inform (input_location, " %qD", name);
3226 inform (input_location, " <anonymous>");
3228 parameter_packs = TREE_CHAIN (parameter_packs);
3237 /* Expand any parameter packs that occur in the template arguments in
3240 expand_template_argument_pack (tree args)
3242 tree result_args = NULL_TREE;
3243 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3244 int num_result_args = -1;
3245 int non_default_args_count = -1;
3247 /* First, determine if we need to expand anything, and the number of
3248 slots we'll need. */
3249 for (in_arg = 0; in_arg < nargs; ++in_arg)
3251 tree arg = TREE_VEC_ELT (args, in_arg);
3252 if (arg == NULL_TREE)
3254 if (ARGUMENT_PACK_P (arg))
3256 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3257 if (num_result_args < 0)
3258 num_result_args = in_arg + num_packed;
3260 num_result_args += num_packed;
3264 if (num_result_args >= 0)
3269 /* If no expansion is necessary, we're done. */
3270 if (num_result_args < 0)
3273 /* Expand arguments. */
3274 result_args = make_tree_vec (num_result_args);
3275 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3276 non_default_args_count =
3277 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3278 for (in_arg = 0; in_arg < nargs; ++in_arg)
3280 tree arg = TREE_VEC_ELT (args, in_arg);
3281 if (ARGUMENT_PACK_P (arg))
3283 tree packed = ARGUMENT_PACK_ARGS (arg);
3284 int i, num_packed = TREE_VEC_LENGTH (packed);
3285 for (i = 0; i < num_packed; ++i, ++out_arg)
3286 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3287 if (non_default_args_count > 0)
3288 non_default_args_count += num_packed;
3292 TREE_VEC_ELT (result_args, out_arg) = arg;
3296 if (non_default_args_count >= 0)
3297 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3301 /* Checks if DECL shadows a template parameter.
3303 [temp.local]: A template-parameter shall not be redeclared within its
3304 scope (including nested scopes).
3306 Emits an error and returns TRUE if the DECL shadows a parameter,
3307 returns FALSE otherwise. */
3310 check_template_shadow (tree decl)
3314 /* If we're not in a template, we can't possibly shadow a template
3316 if (!current_template_parms)
3319 /* Figure out what we're shadowing. */
3320 if (TREE_CODE (decl) == OVERLOAD)
3321 decl = OVL_CURRENT (decl);
3322 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3324 /* If there's no previous binding for this name, we're not shadowing
3325 anything, let alone a template parameter. */
3329 /* If we're not shadowing a template parameter, we're done. Note
3330 that OLDDECL might be an OVERLOAD (or perhaps even an
3331 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3333 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3336 /* We check for decl != olddecl to avoid bogus errors for using a
3337 name inside a class. We check TPFI to avoid duplicate errors for
3338 inline member templates. */
3340 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3343 error ("declaration of %q+#D", decl);
3344 error (" shadows template parm %q+#D", olddecl);
3348 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3349 ORIG_LEVEL, DECL, and TYPE. */
3352 build_template_parm_index (int index,
3358 tree t = make_node (TEMPLATE_PARM_INDEX);
3359 TEMPLATE_PARM_IDX (t) = index;
3360 TEMPLATE_PARM_LEVEL (t) = level;
3361 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3362 TEMPLATE_PARM_DECL (t) = decl;
3363 TREE_TYPE (t) = type;
3364 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3365 TREE_READONLY (t) = TREE_READONLY (decl);
3370 /* Find the canonical type parameter for the given template type
3371 parameter. Returns the canonical type parameter, which may be TYPE
3372 if no such parameter existed. */
3374 canonical_type_parameter (tree type)
3377 int idx = TEMPLATE_TYPE_IDX (type);
3378 if (!canonical_template_parms)
3379 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3381 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3382 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3384 list = VEC_index (tree, canonical_template_parms, idx);
3385 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3386 list = TREE_CHAIN (list);
3389 return TREE_VALUE (list);
3392 VEC_replace(tree, canonical_template_parms, idx,
3393 tree_cons (NULL_TREE, type,
3394 VEC_index (tree, canonical_template_parms, idx)));
3399 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3400 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3401 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3402 new one is created. */
3405 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3406 tsubst_flags_t complain)
3408 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3409 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3410 != TEMPLATE_PARM_LEVEL (index) - levels)
3411 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3413 tree orig_decl = TEMPLATE_PARM_DECL (index);
3416 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3417 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3418 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3419 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3420 DECL_ARTIFICIAL (decl) = 1;
3421 SET_DECL_TEMPLATE_PARM_P (decl);
3423 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3424 TEMPLATE_PARM_LEVEL (index) - levels,
3425 TEMPLATE_PARM_ORIG_LEVEL (index),
3427 TEMPLATE_PARM_DESCENDANTS (index) = t;
3428 TEMPLATE_PARM_PARAMETER_PACK (t)
3429 = TEMPLATE_PARM_PARAMETER_PACK (index);
3431 /* Template template parameters need this. */
3432 if (TREE_CODE (decl) == TEMPLATE_DECL)
3433 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3434 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3438 return TEMPLATE_PARM_DESCENDANTS (index);
3441 /* Process information from new template parameter PARM and append it to the
3442 LIST being built. This new parameter is a non-type parameter iff
3443 IS_NON_TYPE is true. This new parameter is a parameter
3444 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3448 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3449 bool is_parameter_pack)
3456 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3457 defval = TREE_PURPOSE (parm);
3461 tree p = tree_last (list);
3463 if (p && TREE_VALUE (p) != error_mark_node)
3466 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3467 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3469 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3479 parm = TREE_VALUE (parm);
3481 SET_DECL_TEMPLATE_PARM_P (parm);
3483 if (TREE_TYPE (parm) == error_mark_node)
3485 err_parm_list = build_tree_list (defval, parm);
3486 TREE_VALUE (err_parm_list) = error_mark_node;
3487 return chainon (list, err_parm_list);
3493 The top-level cv-qualifiers on the template-parameter are
3494 ignored when determining its type. */
3495 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3496 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3498 err_parm_list = build_tree_list (defval, parm);
3499 TREE_VALUE (err_parm_list) = error_mark_node;
3500 return chainon (list, err_parm_list);
3503 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3505 /* This template parameter is not a parameter pack, but it
3506 should be. Complain about "bare" parameter packs. */
3507 check_for_bare_parameter_packs (TREE_TYPE (parm));
3509 /* Recover by calling this a parameter pack. */
3510 is_parameter_pack = true;
3514 /* A template parameter is not modifiable. */
3515 TREE_CONSTANT (parm) = 1;
3516 TREE_READONLY (parm) = 1;
3517 decl = build_decl (parm_loc,
3518 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3519 TREE_CONSTANT (decl) = 1;
3520 TREE_READONLY (decl) = 1;
3521 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3522 = build_template_parm_index (idx, processing_template_decl,
3523 processing_template_decl,
3524 decl, TREE_TYPE (parm));
3526 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3527 = is_parameter_pack;
3532 parm = TREE_VALUE (TREE_VALUE (parm));
3534 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3536 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3537 /* This is for distinguishing between real templates and template
3538 template parameters */
3539 TREE_TYPE (parm) = t;
3540 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3545 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3546 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3547 decl = build_decl (parm_loc,
3548 TYPE_DECL, parm, t);
3551 TYPE_NAME (t) = decl;
3552 TYPE_STUB_DECL (t) = decl;
3554 TEMPLATE_TYPE_PARM_INDEX (t)
3555 = build_template_parm_index (idx, processing_template_decl,
3556 processing_template_decl,
3557 decl, TREE_TYPE (parm));
3558 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3559 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3561 DECL_ARTIFICIAL (decl) = 1;
3562 SET_DECL_TEMPLATE_PARM_P (decl);
3564 parm = build_tree_list (defval, parm);
3565 return chainon (list, parm);
3568 /* The end of a template parameter list has been reached. Process the
3569 tree list into a parameter vector, converting each parameter into a more
3570 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3574 end_template_parm_list (tree parms)
3578 tree saved_parmlist = make_tree_vec (list_length (parms));
3580 current_template_parms
3581 = tree_cons (size_int (processing_template_decl),
3582 saved_parmlist, current_template_parms);
3584 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3586 next = TREE_CHAIN (parm);
3587 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3588 TREE_CHAIN (parm) = NULL_TREE;
3589 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL)
3590 TEMPLATE_TYPE_PARM_SIBLING_PARMS (TREE_TYPE (TREE_VALUE (parm))) =
3591 current_template_parms;
3594 --processing_template_parmlist;
3596 return saved_parmlist;
3599 /* end_template_decl is called after a template declaration is seen. */
3602 end_template_decl (void)
3604 reset_specialization ();
3606 if (! processing_template_decl)
3609 /* This matches the pushlevel in begin_template_parm_list. */
3612 --processing_template_decl;
3613 current_template_parms = TREE_CHAIN (current_template_parms);
3616 /* Within the declaration of a template, return all levels of template
3617 parameters that apply. The template parameters are represented as
3618 a TREE_VEC, in the form documented in cp-tree.h for template
3622 current_template_args (void)
3625 tree args = NULL_TREE;
3626 int length = TMPL_PARMS_DEPTH (current_template_parms);
3629 /* If there is only one level of template parameters, we do not
3630 create a TREE_VEC of TREE_VECs. Instead, we return a single
3631 TREE_VEC containing the arguments. */
3633 args = make_tree_vec (length);
3635 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3637 tree a = copy_node (TREE_VALUE (header));
3640 TREE_TYPE (a) = NULL_TREE;
3641 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3643 tree t = TREE_VEC_ELT (a, i);
3645 /* T will be a list if we are called from within a
3646 begin/end_template_parm_list pair, but a vector directly
3647 if within a begin/end_member_template_processing pair. */
3648 if (TREE_CODE (t) == TREE_LIST)
3652 if (!error_operand_p (t))
3654 if (TREE_CODE (t) == TYPE_DECL
3655 || TREE_CODE (t) == TEMPLATE_DECL)
3659 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3661 /* Turn this argument into a TYPE_ARGUMENT_PACK
3662 with a single element, which expands T. */
3663 tree vec = make_tree_vec (1);
3664 #ifdef ENABLE_CHECKING
3665 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3666 (vec, TREE_VEC_LENGTH (vec));
3668 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3670 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3671 SET_ARGUMENT_PACK_ARGS (t, vec);
3676 t = DECL_INITIAL (t);
3678 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3680 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3681 with a single element, which expands T. */
3682 tree vec = make_tree_vec (1);
3683 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3684 #ifdef ENABLE_CHECKING
3685 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3686 (vec, TREE_VEC_LENGTH (vec));
3688 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3690 t = make_node (NONTYPE_ARGUMENT_PACK);
3691 SET_ARGUMENT_PACK_ARGS (t, vec);
3692 TREE_TYPE (t) = type;
3695 TREE_VEC_ELT (a, i) = t;
3700 #ifdef ENABLE_CHECKING
3701 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
3705 TREE_VEC_ELT (args, --l) = a;
3713 /* Update the declared TYPE by doing any lookups which were thought to be
3714 dependent, but are not now that we know the SCOPE of the declarator. */
3717 maybe_update_decl_type (tree orig_type, tree scope)
3719 tree type = orig_type;
3721 if (type == NULL_TREE)
3724 if (TREE_CODE (orig_type) == TYPE_DECL)
3725 type = TREE_TYPE (type);
3727 if (scope && TYPE_P (scope) && dependent_type_p (scope)
3728 && dependent_type_p (type)
3729 /* Don't bother building up the args in this case. */
3730 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
3732 /* tsubst in the args corresponding to the template parameters,
3733 including auto if present. Most things will be unchanged, but
3734 make_typename_type and tsubst_qualified_id will resolve
3735 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
3736 tree args = current_template_args ();
3737 tree auto_node = type_uses_auto (type);
3741 tree auto_vec = make_tree_vec (1);
3742 TREE_VEC_ELT (auto_vec, 0) = auto_node;
3743 args = add_to_template_args (args, auto_vec);
3745 pushed = push_scope (scope);
3746 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
3751 if (type == error_mark_node)
3754 if (TREE_CODE (orig_type) == TYPE_DECL)
3756 if (same_type_p (type, TREE_TYPE (orig_type)))
3759 type = TYPE_NAME (type);
3764 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3765 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3766 a member template. Used by push_template_decl below. */
3769 build_template_decl (tree decl, tree parms, bool member_template_p)
3771 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3772 DECL_TEMPLATE_PARMS (tmpl) = parms;
3773 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3774 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3779 struct template_parm_data
3781 /* The level of the template parameters we are currently
3785 /* The index of the specialization argument we are currently
3789 /* An array whose size is the number of template parameters. The
3790 elements are nonzero if the parameter has been used in any one
3791 of the arguments processed so far. */
3794 /* An array whose size is the number of template arguments. The
3795 elements are nonzero if the argument makes use of template
3796 parameters of this level. */
3797 int* arg_uses_template_parms;
3800 /* Subroutine of push_template_decl used to see if each template
3801 parameter in a partial specialization is used in the explicit
3802 argument list. If T is of the LEVEL given in DATA (which is
3803 treated as a template_parm_data*), then DATA->PARMS is marked
3807 mark_template_parm (tree t, void* data)
3811 struct template_parm_data* tpd = (struct template_parm_data*) data;
3813 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3815 level = TEMPLATE_PARM_LEVEL (t);
3816 idx = TEMPLATE_PARM_IDX (t);
3820 level = TEMPLATE_TYPE_LEVEL (t);
3821 idx = TEMPLATE_TYPE_IDX (t);
3824 if (level == tpd->level)
3826 tpd->parms[idx] = 1;
3827 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3830 /* Return zero so that for_each_template_parm will continue the
3831 traversal of the tree; we want to mark *every* template parm. */
3835 /* Process the partial specialization DECL. */
3838 process_partial_specialization (tree decl)
3840 tree type = TREE_TYPE (decl);
3841 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3842 tree specargs = CLASSTYPE_TI_ARGS (type);
3843 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3844 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3847 int nargs = TREE_VEC_LENGTH (inner_args);
3850 bool did_error_intro = false;
3851 struct template_parm_data tpd;
3852 struct template_parm_data tpd2;
3854 gcc_assert (current_template_parms);
3856 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3857 ntparms = TREE_VEC_LENGTH (inner_parms);
3859 /* We check that each of the template parameters given in the
3860 partial specialization is used in the argument list to the
3861 specialization. For example:
3863 template <class T> struct S;
3864 template <class T> struct S<T*>;
3866 The second declaration is OK because `T*' uses the template
3867 parameter T, whereas
3869 template <class T> struct S<int>;
3871 is no good. Even trickier is:
3882 The S2<T> declaration is actually invalid; it is a
3883 full-specialization. Of course,
3886 struct S2<T (*)(U)>;
3888 or some such would have been OK. */
3889 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3890 tpd.parms = XALLOCAVEC (int, ntparms);
3891 memset (tpd.parms, 0, sizeof (int) * ntparms);
3893 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
3894 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3895 for (i = 0; i < nargs; ++i)
3897 tpd.current_arg = i;
3898 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3899 &mark_template_parm,
3902 /*include_nondeduced_p=*/false);
3904 for (i = 0; i < ntparms; ++i)
3905 if (tpd.parms[i] == 0)
3907 /* One of the template parms was not used in the
3909 if (!did_error_intro)
3911 error ("template parameters not used in partial specialization:");
3912 did_error_intro = true;
3915 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3918 if (did_error_intro)
3919 return error_mark_node;
3921 /* [temp.class.spec]
3923 The argument list of the specialization shall not be identical to
3924 the implicit argument list of the primary template. */
3925 if (comp_template_args
3927 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3929 error ("partial specialization %qT does not specialize any template arguments", type);
3931 /* [temp.class.spec]
3933 A partially specialized non-type argument expression shall not
3934 involve template parameters of the partial specialization except
3935 when the argument expression is a simple identifier.
3937 The type of a template parameter corresponding to a specialized
3938 non-type argument shall not be dependent on a parameter of the
3941 Also, we verify that pack expansions only occur at the
3942 end of the argument list. */
3943 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3945 for (i = 0; i < nargs; ++i)
3947 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3948 tree arg = TREE_VEC_ELT (inner_args, i);
3949 tree packed_args = NULL_TREE;
3952 if (ARGUMENT_PACK_P (arg))
3954 /* Extract the arguments from the argument pack. We'll be
3955 iterating over these in the following loop. */
3956 packed_args = ARGUMENT_PACK_ARGS (arg);
3957 len = TREE_VEC_LENGTH (packed_args);
3960 for (j = 0; j < len; j++)
3963 /* Get the Jth argument in the parameter pack. */
3964 arg = TREE_VEC_ELT (packed_args, j);
3966 if (PACK_EXPANSION_P (arg))
3968 /* Pack expansions must come at the end of the
3970 if ((packed_args && j < len - 1)
3971 || (!packed_args && i < nargs - 1))
3973 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3974 error ("parameter pack argument %qE must be at the "
3975 "end of the template argument list", arg);
3977 error ("parameter pack argument %qT must be at the "
3978 "end of the template argument list", arg);
3982 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3983 /* We only care about the pattern. */
3984 arg = PACK_EXPANSION_PATTERN (arg);
3986 if (/* These first two lines are the `non-type' bit. */
3988 && TREE_CODE (arg) != TEMPLATE_DECL
3989 /* This next line is the `argument expression is not just a
3990 simple identifier' condition and also the `specialized
3991 non-type argument' bit. */
3992 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3994 if ((!packed_args && tpd.arg_uses_template_parms[i])
3995 || (packed_args && uses_template_parms (arg)))
3996 error ("template argument %qE involves template parameter(s)",
4000 /* Look at the corresponding template parameter,
4001 marking which template parameters its type depends
4003 tree type = TREE_TYPE (parm);
4007 /* We haven't yet initialized TPD2. Do so now. */
4008 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4009 /* The number of parameters here is the number in the
4010 main template, which, as checked in the assertion
4012 tpd2.parms = XALLOCAVEC (int, nargs);
4014 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4017 /* Mark the template parameters. But this time, we're
4018 looking for the template parameters of the main
4019 template, not in the specialization. */
4020 tpd2.current_arg = i;
4021 tpd2.arg_uses_template_parms[i] = 0;
4022 memset (tpd2.parms, 0, sizeof (int) * nargs);
4023 for_each_template_parm (type,
4024 &mark_template_parm,
4027 /*include_nondeduced_p=*/false);
4029 if (tpd2.arg_uses_template_parms [i])
4031 /* The type depended on some template parameters.
4032 If they are fully specialized in the
4033 specialization, that's OK. */
4036 for (j = 0; j < nargs; ++j)
4037 if (tpd2.parms[j] != 0
4038 && tpd.arg_uses_template_parms [j])
4041 error_n (input_location, count,
4042 "type %qT of template argument %qE depends "
4043 "on a template parameter",
4044 "type %qT of template argument %qE depends "
4045 "on template parameters",
4054 /* We should only get here once. */
4055 gcc_assert (!COMPLETE_TYPE_P (type));
4057 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4058 = tree_cons (specargs, inner_parms,
4059 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4060 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4062 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4063 inst = TREE_CHAIN (inst))
4065 tree inst_type = TREE_VALUE (inst);
4066 if (COMPLETE_TYPE_P (inst_type)
4067 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4069 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4070 if (spec && TREE_TYPE (spec) == type)
4071 permerror (input_location,
4072 "partial specialization of %qT after instantiation "
4073 "of %qT", type, inst_type);
4080 /* Check that a template declaration's use of default arguments and
4081 parameter packs is not invalid. Here, PARMS are the template
4082 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4083 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4087 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4088 declaration (but not a definition); 1 indicates a declaration, 2
4089 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4090 emitted for extraneous default arguments.
4092 Returns TRUE if there were no errors found, FALSE otherwise. */
4095 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4096 int is_partial, int is_friend_decl)
4099 int last_level_to_check;
4101 bool no_errors = true;
4105 A default template-argument shall not be specified in a
4106 function template declaration or a function template definition, nor
4107 in the template-parameter-list of the definition of a member of a
4110 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4111 /* You can't have a function template declaration in a local
4112 scope, nor you can you define a member of a class template in a
4116 if (current_class_type
4117 && !TYPE_BEING_DEFINED (current_class_type)
4118 && DECL_LANG_SPECIFIC (decl)
4119 && DECL_DECLARES_FUNCTION_P (decl)
4120 /* If this is either a friend defined in the scope of the class
4121 or a member function. */
4122 && (DECL_FUNCTION_MEMBER_P (decl)
4123 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4124 : DECL_FRIEND_CONTEXT (decl)
4125 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4127 /* And, if it was a member function, it really was defined in
4128 the scope of the class. */
4129 && (!DECL_FUNCTION_MEMBER_P (decl)
4130 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4131 /* We already checked these parameters when the template was
4132 declared, so there's no need to do it again now. This function
4133 was defined in class scope, but we're processing it's body now
4134 that the class is complete. */
4137 /* Core issue 226 (C++0x only): the following only applies to class
4139 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4143 If a template-parameter has a default template-argument, all
4144 subsequent template-parameters shall have a default
4145 template-argument supplied. */
4146 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4148 tree inner_parms = TREE_VALUE (parm_level);
4149 int ntparms = TREE_VEC_LENGTH (inner_parms);
4150 int seen_def_arg_p = 0;
4153 for (i = 0; i < ntparms; ++i)
4155 tree parm = TREE_VEC_ELT (inner_parms, i);
4157 if (parm == error_mark_node)
4160 if (TREE_PURPOSE (parm))
4162 else if (seen_def_arg_p
4163 && !template_parameter_pack_p (TREE_VALUE (parm)))
4165 error ("no default argument for %qD", TREE_VALUE (parm));
4166 /* For better subsequent error-recovery, we indicate that
4167 there should have been a default argument. */
4168 TREE_PURPOSE (parm) = error_mark_node;
4174 /* Don't complain about an enclosing partial
4176 && parm_level == parms
4177 && TREE_CODE (decl) == TYPE_DECL
4179 && template_parameter_pack_p (TREE_VALUE (parm)))
4181 /* A primary class template can only have one
4182 parameter pack, at the end of the template
4185 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4186 error ("parameter pack %qE must be at the end of the"
4187 " template parameter list", TREE_VALUE (parm));
4189 error ("parameter pack %qT must be at the end of the"
4190 " template parameter list",
4191 TREE_TYPE (TREE_VALUE (parm)));
4193 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4201 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4205 /* For an ordinary class template, default template arguments are
4206 allowed at the innermost level, e.g.:
4207 template <class T = int>
4209 but, in a partial specialization, they're not allowed even
4210 there, as we have in [temp.class.spec]:
4212 The template parameter list of a specialization shall not
4213 contain default template argument values.
4215 So, for a partial specialization, or for a function template
4216 (in C++98/C++03), we look at all of them. */
4219 /* But, for a primary class template that is not a partial
4220 specialization we look at all template parameters except the
4222 parms = TREE_CHAIN (parms);
4224 /* Figure out what error message to issue. */
4225 if (is_friend_decl == 2)
4226 msg = G_("default template arguments may not be used in function template "
4227 "friend re-declaration");
4228 else if (is_friend_decl)
4229 msg = G_("default template arguments may not be used in function template "
4230 "friend declarations");
4231 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4232 msg = G_("default template arguments may not be used in function templates "
4233 "without -std=c++0x or -std=gnu++0x");
4234 else if (is_partial)
4235 msg = G_("default template arguments may not be used in "
4236 "partial specializations");
4238 msg = G_("default argument for template parameter for class enclosing %qD");
4240 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4241 /* If we're inside a class definition, there's no need to
4242 examine the parameters to the class itself. On the one
4243 hand, they will be checked when the class is defined, and,
4244 on the other, default arguments are valid in things like:
4245 template <class T = double>
4246 struct S { template <class U> void f(U); };
4247 Here the default argument for `S' has no bearing on the
4248 declaration of `f'. */
4249 last_level_to_check = template_class_depth (current_class_type) + 1;
4251 /* Check everything. */
4252 last_level_to_check = 0;
4254 for (parm_level = parms;
4255 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4256 parm_level = TREE_CHAIN (parm_level))
4258 tree inner_parms = TREE_VALUE (parm_level);
4262 ntparms = TREE_VEC_LENGTH (inner_parms);
4263 for (i = 0; i < ntparms; ++i)
4265 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4268 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4273 if (is_friend_decl == 2)
4280 /* Clear out the default argument so that we are not
4282 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4286 /* At this point, if we're still interested in issuing messages,
4287 they must apply to classes surrounding the object declared. */
4289 msg = G_("default argument for template parameter for class "
4296 /* Worker for push_template_decl_real, called via
4297 for_each_template_parm. DATA is really an int, indicating the
4298 level of the parameters we are interested in. If T is a template
4299 parameter of that level, return nonzero. */
4302 template_parm_this_level_p (tree t, void* data)
4304 int this_level = *(int *)data;
4307 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4308 level = TEMPLATE_PARM_LEVEL (t);
4310 level = TEMPLATE_TYPE_LEVEL (t);
4311 return level == this_level;
4314 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4315 parameters given by current_template_args, or reuses a
4316 previously existing one, if appropriate. Returns the DECL, or an
4317 equivalent one, if it is replaced via a call to duplicate_decls.
4319 If IS_FRIEND is true, DECL is a friend declaration. */
4322 push_template_decl_real (tree decl, bool is_friend)
4330 int new_template_p = 0;
4331 /* True if the template is a member template, in the sense of
4333 bool member_template_p = false;
4335 if (decl == error_mark_node || !current_template_parms)
4336 return error_mark_node;
4338 /* See if this is a partial specialization. */
4339 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4340 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4341 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4343 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4347 /* For a friend, we want the context of the friend function, not
4348 the type of which it is a friend. */
4349 ctx = DECL_CONTEXT (decl);
4350 else if (CP_DECL_CONTEXT (decl)
4351 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4352 /* In the case of a virtual function, we want the class in which
4354 ctx = CP_DECL_CONTEXT (decl);
4356 /* Otherwise, if we're currently defining some class, the DECL
4357 is assumed to be a member of the class. */
4358 ctx = current_scope ();
4360 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4363 if (!DECL_CONTEXT (decl))
4364 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4366 /* See if this is a primary template. */
4367 if (is_friend && ctx)
4368 /* A friend template that specifies a class context, i.e.
4369 template <typename T> friend void A<T>::f();
4373 primary = template_parm_scope_p ();
4377 if (DECL_CLASS_SCOPE_P (decl))
4378 member_template_p = true;
4379 if (TREE_CODE (decl) == TYPE_DECL
4380 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4382 error ("template class without a name");
4383 return error_mark_node;
4385 else if (TREE_CODE (decl) == FUNCTION_DECL)
4387 if (DECL_DESTRUCTOR_P (decl))
4391 A destructor shall not be a member template. */
4392 error ("destructor %qD declared as member template", decl);
4393 return error_mark_node;
4395 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4396 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4397 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4398 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4399 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4400 == void_list_node)))
4402 /* [basic.stc.dynamic.allocation]
4404 An allocation function can be a function
4405 template. ... Template allocation functions shall
4406 have two or more parameters. */
4407 error ("invalid template declaration of %qD", decl);
4408 return error_mark_node;
4411 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4412 && CLASS_TYPE_P (TREE_TYPE (decl)))
4416 error ("template declaration of %q#D", decl);
4417 return error_mark_node;
4421 /* Check to see that the rules regarding the use of default
4422 arguments are not being violated. */
4423 check_default_tmpl_args (decl, current_template_parms,
4424 primary, is_partial, /*is_friend_decl=*/0);
4426 /* Ensure that there are no parameter packs in the type of this
4427 declaration that have not been expanded. */
4428 if (TREE_CODE (decl) == FUNCTION_DECL)
4430 /* Check each of the arguments individually to see if there are
4431 any bare parameter packs. */
4432 tree type = TREE_TYPE (decl);
4433 tree arg = DECL_ARGUMENTS (decl);
4434 tree argtype = TYPE_ARG_TYPES (type);
4436 while (arg && argtype)
4438 if (!FUNCTION_PARAMETER_PACK_P (arg)
4439 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4441 /* This is a PARM_DECL that contains unexpanded parameter
4442 packs. We have already complained about this in the
4443 check_for_bare_parameter_packs call, so just replace
4444 these types with ERROR_MARK_NODE. */
4445 TREE_TYPE (arg) = error_mark_node;
4446 TREE_VALUE (argtype) = error_mark_node;
4449 arg = DECL_CHAIN (arg);
4450 argtype = TREE_CHAIN (argtype);
4453 /* Check for bare parameter packs in the return type and the
4454 exception specifiers. */
4455 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4456 /* Errors were already issued, set return type to int
4457 as the frontend doesn't expect error_mark_node as
4459 TREE_TYPE (type) = integer_type_node;
4460 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4461 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4463 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4465 TREE_TYPE (decl) = error_mark_node;
4466 return error_mark_node;
4470 return process_partial_specialization (decl);
4472 args = current_template_args ();
4475 || TREE_CODE (ctx) == FUNCTION_DECL
4476 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4477 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4479 if (DECL_LANG_SPECIFIC (decl)
4480 && DECL_TEMPLATE_INFO (decl)
4481 && DECL_TI_TEMPLATE (decl))
4482 tmpl = DECL_TI_TEMPLATE (decl);
4483 /* If DECL is a TYPE_DECL for a class-template, then there won't
4484 be DECL_LANG_SPECIFIC. The information equivalent to
4485 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4486 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4487 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4488 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4490 /* Since a template declaration already existed for this
4491 class-type, we must be redeclaring it here. Make sure
4492 that the redeclaration is valid. */
4493 redeclare_class_template (TREE_TYPE (decl),
4494 current_template_parms);
4495 /* We don't need to create a new TEMPLATE_DECL; just use the
4496 one we already had. */
4497 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4501 tmpl = build_template_decl (decl, current_template_parms,
4505 if (DECL_LANG_SPECIFIC (decl)
4506 && DECL_TEMPLATE_SPECIALIZATION (decl))
4508 /* A specialization of a member template of a template
4510 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4511 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4512 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4518 tree a, t, current, parms;
4520 tree tinfo = get_template_info (decl);
4524 error ("template definition of non-template %q#D", decl);
4525 return error_mark_node;
4528 tmpl = TI_TEMPLATE (tinfo);
4530 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4531 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4532 && DECL_TEMPLATE_SPECIALIZATION (decl)
4533 && DECL_MEMBER_TEMPLATE_P (tmpl))
4537 /* The declaration is a specialization of a member
4538 template, declared outside the class. Therefore, the
4539 innermost template arguments will be NULL, so we
4540 replace them with the arguments determined by the
4541 earlier call to check_explicit_specialization. */
4542 args = DECL_TI_ARGS (decl);
4545 = build_template_decl (decl, current_template_parms,
4547 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4548 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4549 DECL_TI_TEMPLATE (decl) = new_tmpl;
4550 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4551 DECL_TEMPLATE_INFO (new_tmpl)
4552 = build_template_info (tmpl, args);
4554 register_specialization (new_tmpl,
4555 most_general_template (tmpl),
4561 /* Make sure the template headers we got make sense. */
4563 parms = DECL_TEMPLATE_PARMS (tmpl);
4564 i = TMPL_PARMS_DEPTH (parms);
4565 if (TMPL_ARGS_DEPTH (args) != i)
4567 error ("expected %d levels of template parms for %q#D, got %d",
4568 i, decl, TMPL_ARGS_DEPTH (args));
4571 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4573 a = TMPL_ARGS_LEVEL (args, i);
4574 t = INNERMOST_TEMPLATE_PARMS (parms);
4576 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4578 if (current == decl)
4579 error ("got %d template parameters for %q#D",
4580 TREE_VEC_LENGTH (a), decl);
4582 error ("got %d template parameters for %q#T",
4583 TREE_VEC_LENGTH (a), current);
4584 error (" but %d required", TREE_VEC_LENGTH (t));
4585 return error_mark_node;
4588 if (current == decl)
4590 else if (current == NULL_TREE)
4591 /* Can happen in erroneous input. */
4594 current = (TYPE_P (current)
4595 ? TYPE_CONTEXT (current)
4596 : DECL_CONTEXT (current));
4599 /* Check that the parms are used in the appropriate qualifying scopes
4600 in the declarator. */
4601 if (!comp_template_args
4603 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4606 template arguments to %qD do not match original template %qD",
4607 decl, DECL_TEMPLATE_RESULT (tmpl));
4608 if (!uses_template_parms (TI_ARGS (tinfo)))
4609 inform (input_location, "use template<> for an explicit specialization");
4610 /* Avoid crash in import_export_decl. */
4611 DECL_INTERFACE_KNOWN (decl) = 1;
4612 return error_mark_node;
4616 DECL_TEMPLATE_RESULT (tmpl) = decl;
4617 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4619 /* Push template declarations for global functions and types. Note
4620 that we do not try to push a global template friend declared in a
4621 template class; such a thing may well depend on the template
4622 parameters of the class. */
4623 if (new_template_p && !ctx
4624 && !(is_friend && template_class_depth (current_class_type) > 0))
4626 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4627 if (tmpl == error_mark_node)
4628 return error_mark_node;
4630 /* Hide template friend classes that haven't been declared yet. */
4631 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4633 DECL_ANTICIPATED (tmpl) = 1;
4634 DECL_FRIEND_P (tmpl) = 1;
4640 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4643 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4644 if (DECL_CONV_FN_P (tmpl))
4646 int depth = TMPL_PARMS_DEPTH (parms);
4648 /* It is a conversion operator. See if the type converted to
4649 depends on innermost template operands. */
4651 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4653 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4656 /* Give template template parms a DECL_CONTEXT of the template
4657 for which they are a parameter. */
4658 parms = INNERMOST_TEMPLATE_PARMS (parms);
4659 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4661 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4662 if (TREE_CODE (parm) == TEMPLATE_DECL)
4663 DECL_CONTEXT (parm) = tmpl;
4667 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4668 back to its most general template. If TMPL is a specialization,
4669 ARGS may only have the innermost set of arguments. Add the missing
4670 argument levels if necessary. */
4671 if (DECL_TEMPLATE_INFO (tmpl))
4672 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4674 info = build_template_info (tmpl, args);
4676 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4677 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4678 else if (DECL_LANG_SPECIFIC (decl))
4679 DECL_TEMPLATE_INFO (decl) = info;
4681 return DECL_TEMPLATE_RESULT (tmpl);
4685 push_template_decl (tree decl)
4687 return push_template_decl_real (decl, false);
4690 /* Called when a class template TYPE is redeclared with the indicated
4691 template PARMS, e.g.:
4693 template <class T> struct S;
4694 template <class T> struct S {}; */
4697 redeclare_class_template (tree type, tree parms)
4703 if (!TYPE_TEMPLATE_INFO (type))
4705 error ("%qT is not a template type", type);
4709 tmpl = TYPE_TI_TEMPLATE (type);
4710 if (!PRIMARY_TEMPLATE_P (tmpl))
4711 /* The type is nested in some template class. Nothing to worry
4712 about here; there are no new template parameters for the nested
4718 error ("template specifiers not specified in declaration of %qD",
4723 parms = INNERMOST_TEMPLATE_PARMS (parms);
4724 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4726 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4728 error_n (input_location, TREE_VEC_LENGTH (parms),
4729 "redeclared with %d template parameter",
4730 "redeclared with %d template parameters",
4731 TREE_VEC_LENGTH (parms));
4732 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
4733 "previous declaration %q+D used %d template parameter",
4734 "previous declaration %q+D used %d template parameters",
4735 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4739 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4746 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4747 || TREE_VEC_ELT (parms, i) == error_mark_node)
4750 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4751 if (tmpl_parm == error_mark_node)
4754 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4755 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4756 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4758 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4760 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4761 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4762 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4763 || (TREE_CODE (tmpl_parm) != PARM_DECL
4764 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4765 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4766 || (TREE_CODE (tmpl_parm) == PARM_DECL
4767 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4768 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
4770 error ("template parameter %q+#D", tmpl_parm);
4771 error ("redeclared here as %q#D", parm);
4775 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4777 /* We have in [temp.param]:
4779 A template-parameter may not be given default arguments
4780 by two different declarations in the same scope. */
4781 error_at (input_location, "redefinition of default argument for %q#D", parm);
4782 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4783 "original definition appeared here");
4787 if (parm_default != NULL_TREE)
4788 /* Update the previous template parameters (which are the ones
4789 that will really count) with the new default value. */
4790 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4791 else if (tmpl_default != NULL_TREE)
4792 /* Update the new parameters, too; they'll be used as the
4793 parameters for any members. */
4794 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4800 /* Simplify EXPR if it is a non-dependent expression. Returns the
4801 (possibly simplified) expression. */
4804 fold_non_dependent_expr (tree expr)
4806 if (expr == NULL_TREE)
4809 /* If we're in a template, but EXPR isn't value dependent, simplify
4810 it. We're supposed to treat:
4812 template <typename T> void f(T[1 + 1]);
4813 template <typename T> void f(T[2]);
4815 as two declarations of the same function, for example. */
4816 if (processing_template_decl
4817 && !type_dependent_expression_p (expr)
4818 && !value_dependent_expression_p (expr))
4820 HOST_WIDE_INT saved_processing_template_decl;
4822 saved_processing_template_decl = processing_template_decl;
4823 processing_template_decl = 0;
4824 expr = tsubst_copy_and_build (expr,
4827 /*in_decl=*/NULL_TREE,
4828 /*function_p=*/false,
4829 /*integral_constant_expression_p=*/true);
4830 processing_template_decl = saved_processing_template_decl;
4835 /* EXPR is an expression which is used in a constant-expression context.
4836 For instance, it could be a VAR_DECL with a constant initializer.
4837 Extract the innermost constant expression.
4839 This is basically a more powerful version of
4840 integral_constant_value, which can be used also in templates where
4841 initializers can maintain a syntactic rather than semantic form
4842 (even if they are non-dependent, for access-checking purposes). */
4845 fold_decl_constant_value (tree expr)
4847 tree const_expr = expr;
4850 expr = fold_non_dependent_expr (const_expr);
4851 const_expr = integral_constant_value (expr);
4853 while (expr != const_expr);
4858 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4859 must be a function or a pointer-to-function type, as specified
4860 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4861 and check that the resulting function has external linkage. */
4864 convert_nontype_argument_function (tree type, tree expr)
4869 fn = instantiate_type (type, fns, tf_none);
4870 if (fn == error_mark_node)
4871 return error_mark_node;
4874 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4875 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4876 if (TREE_CODE (fn_no_ptr) == BASELINK)
4877 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4879 /* [temp.arg.nontype]/1
4881 A template-argument for a non-type, non-template template-parameter
4884 -- the address of an object or function with external linkage. */
4885 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4887 error ("%qE is not a valid template argument for type %qT "
4888 "because function %qD has not external linkage",
4889 expr, type, fn_no_ptr);
4896 /* Subroutine of convert_nontype_argument.
4897 Check if EXPR of type TYPE is a valid pointer-to-member constant.
4898 Emit an error otherwise. */
4901 check_valid_ptrmem_cst_expr (tree type, tree expr)
4904 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
4906 error ("%qE is not a valid template argument for type %qT",
4908 error ("it must be a pointer-to-member of the form `&X::Y'");
4912 /* Returns TRUE iff the address of OP is value-dependent.
4914 14.6.2.4 [temp.dep.temp]:
4915 A non-integral non-type template-argument is dependent if its type is
4916 dependent or it has either of the following forms
4919 and contains a nested-name-specifier which specifies a class-name that
4920 names a dependent type.
4922 We generalize this to just say that the address of a member of a
4923 dependent class is value-dependent; the above doesn't cover the
4924 address of a static data member named with an unqualified-id. */
4927 has_value_dependent_address (tree op)
4929 /* We could use get_inner_reference here, but there's no need;
4930 this is only relevant for template non-type arguments, which
4931 can only be expressed as &id-expression. */
4934 tree ctx = CP_DECL_CONTEXT (op);
4935 if (TYPE_P (ctx) && dependent_type_p (ctx))
4942 /* Attempt to convert the non-type template parameter EXPR to the
4943 indicated TYPE. If the conversion is successful, return the
4944 converted value. If the conversion is unsuccessful, return
4945 NULL_TREE if we issued an error message, or error_mark_node if we
4946 did not. We issue error messages for out-and-out bad template
4947 parameters, but not simply because the conversion failed, since we
4948 might be just trying to do argument deduction. Both TYPE and EXPR
4949 must be non-dependent.
4951 The conversion follows the special rules described in
4952 [temp.arg.nontype], and it is much more strict than an implicit
4955 This function is called twice for each template argument (see
4956 lookup_template_class for a more accurate description of this
4957 problem). This means that we need to handle expressions which
4958 are not valid in a C++ source, but can be created from the
4959 first call (for instance, casts to perform conversions). These
4960 hacks can go away after we fix the double coercion problem. */
4963 convert_nontype_argument (tree type, tree expr)
4967 /* Detect immediately string literals as invalid non-type argument.
4968 This special-case is not needed for correctness (we would easily
4969 catch this later), but only to provide better diagnostic for this
4970 common user mistake. As suggested by DR 100, we do not mention
4971 linkage issues in the diagnostic as this is not the point. */
4972 if (TREE_CODE (expr) == STRING_CST)
4974 error ("%qE is not a valid template argument for type %qT "
4975 "because string literals can never be used in this context",
4980 /* Add the ADDR_EXPR now for the benefit of
4981 value_dependent_expression_p. */
4982 if (TYPE_PTROBV_P (type))
4983 expr = decay_conversion (expr);
4985 /* If we are in a template, EXPR may be non-dependent, but still
4986 have a syntactic, rather than semantic, form. For example, EXPR
4987 might be a SCOPE_REF, rather than the VAR_DECL to which the
4988 SCOPE_REF refers. Preserving the qualifying scope is necessary
4989 so that access checking can be performed when the template is
4990 instantiated -- but here we need the resolved form so that we can
4991 convert the argument. */
4992 if (TYPE_REF_OBJ_P (type)
4993 && has_value_dependent_address (expr))
4994 /* If we want the address and it's value-dependent, don't fold. */;
4996 expr = fold_non_dependent_expr (expr);
4997 if (error_operand_p (expr))
4998 return error_mark_node;
4999 expr_type = TREE_TYPE (expr);
5000 if (TREE_CODE (type) == REFERENCE_TYPE)
5001 expr = mark_lvalue_use (expr);
5003 expr = mark_rvalue_use (expr);
5005 /* HACK: Due to double coercion, we can get a
5006 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5007 which is the tree that we built on the first call (see
5008 below when coercing to reference to object or to reference to
5009 function). We just strip everything and get to the arg.
5010 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5012 if (TREE_CODE (expr) == NOP_EXPR)
5014 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5016 /* ??? Maybe we could use convert_from_reference here, but we
5017 would need to relax its constraints because the NOP_EXPR
5018 could actually change the type to something more cv-qualified,
5019 and this is not folded by convert_from_reference. */
5020 tree addr = TREE_OPERAND (expr, 0);
5021 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
5022 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5023 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5024 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5025 (TREE_TYPE (expr_type),
5026 TREE_TYPE (TREE_TYPE (addr))));
5028 expr = TREE_OPERAND (addr, 0);
5029 expr_type = TREE_TYPE (expr);
5032 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5033 parameter is a pointer to object, through decay and
5034 qualification conversion. Let's strip everything. */
5035 else if (TYPE_PTROBV_P (type))
5038 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5039 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5040 /* Skip the ADDR_EXPR only if it is part of the decay for
5041 an array. Otherwise, it is part of the original argument
5042 in the source code. */
5043 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5044 expr = TREE_OPERAND (expr, 0);
5045 expr_type = TREE_TYPE (expr);
5049 /* [temp.arg.nontype]/5, bullet 1
5051 For a non-type template-parameter of integral or enumeration type,
5052 integral promotions (_conv.prom_) and integral conversions
5053 (_conv.integral_) are applied. */
5054 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5056 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
5057 return error_mark_node;
5059 expr = fold_decl_constant_value (expr);
5060 /* Notice that there are constant expressions like '4 % 0' which
5061 do not fold into integer constants. */
5062 if (TREE_CODE (expr) != INTEGER_CST)
5064 error ("%qE is not a valid template argument for type %qT "
5065 "because it is a non-constant expression", expr, type);
5069 /* At this point, an implicit conversion does what we want,
5070 because we already know that the expression is of integral
5072 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
5073 if (expr == error_mark_node)
5074 return error_mark_node;
5076 /* Conversion was allowed: fold it to a bare integer constant. */
5079 /* [temp.arg.nontype]/5, bullet 2
5081 For a non-type template-parameter of type pointer to object,
5082 qualification conversions (_conv.qual_) and the array-to-pointer
5083 conversion (_conv.array_) are applied. */
5084 else if (TYPE_PTROBV_P (type))
5086 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5088 A template-argument for a non-type, non-template template-parameter
5089 shall be one of: [...]
5091 -- the name of a non-type template-parameter;
5092 -- the address of an object or function with external linkage, [...]
5093 expressed as "& id-expression" where the & is optional if the name
5094 refers to a function or array, or if the corresponding
5095 template-parameter is a reference.
5097 Here, we do not care about functions, as they are invalid anyway
5098 for a parameter of type pointer-to-object. */
5100 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5101 /* Non-type template parameters are OK. */
5103 else if (TREE_CODE (expr) != ADDR_EXPR
5104 && TREE_CODE (expr_type) != ARRAY_TYPE)
5106 if (TREE_CODE (expr) == VAR_DECL)
5108 error ("%qD is not a valid template argument "
5109 "because %qD is a variable, not the address of "
5114 /* Other values, like integer constants, might be valid
5115 non-type arguments of some other type. */
5116 return error_mark_node;
5122 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5123 ? TREE_OPERAND (expr, 0) : expr);
5124 if (TREE_CODE (decl) != VAR_DECL)
5126 error ("%qE is not a valid template argument of type %qT "
5127 "because %qE is not a variable",
5131 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5133 error ("%qE is not a valid template argument of type %qT "
5134 "because %qD does not have external linkage",
5140 expr = decay_conversion (expr);
5141 if (expr == error_mark_node)
5142 return error_mark_node;
5144 expr = perform_qualification_conversions (type, expr);
5145 if (expr == error_mark_node)
5146 return error_mark_node;
5148 /* [temp.arg.nontype]/5, bullet 3
5150 For a non-type template-parameter of type reference to object, no
5151 conversions apply. The type referred to by the reference may be more
5152 cv-qualified than the (otherwise identical) type of the
5153 template-argument. The template-parameter is bound directly to the
5154 template-argument, which must be an lvalue. */
5155 else if (TYPE_REF_OBJ_P (type))
5157 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5159 return error_mark_node;
5161 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5163 error ("%qE is not a valid template argument for type %qT "
5164 "because of conflicts in cv-qualification", expr, type);
5168 if (!real_lvalue_p (expr))
5170 error ("%qE is not a valid template argument for type %qT "
5171 "because it is not an lvalue", expr, type);
5175 /* [temp.arg.nontype]/1
5177 A template-argument for a non-type, non-template template-parameter
5178 shall be one of: [...]
5180 -- the address of an object or function with external linkage. */
5181 if (TREE_CODE (expr) == INDIRECT_REF
5182 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5184 expr = TREE_OPERAND (expr, 0);
5187 error ("%q#D is not a valid template argument for type %qT "
5188 "because a reference variable does not have a constant "
5189 "address", expr, type);
5196 error ("%qE is not a valid template argument for type %qT "
5197 "because it is not an object with external linkage",
5202 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5204 error ("%qE is not a valid template argument for type %qT "
5205 "because object %qD has not external linkage",
5210 expr = build_nop (type, build_address (expr));
5212 /* [temp.arg.nontype]/5, bullet 4
5214 For a non-type template-parameter of type pointer to function, only
5215 the function-to-pointer conversion (_conv.func_) is applied. If the
5216 template-argument represents a set of overloaded functions (or a
5217 pointer to such), the matching function is selected from the set
5219 else if (TYPE_PTRFN_P (type))
5221 /* If the argument is a template-id, we might not have enough
5222 context information to decay the pointer. */
5223 if (!type_unknown_p (expr_type))
5225 expr = decay_conversion (expr);
5226 if (expr == error_mark_node)
5227 return error_mark_node;
5230 expr = convert_nontype_argument_function (type, expr);
5231 if (!expr || expr == error_mark_node)
5234 if (TREE_CODE (expr) != ADDR_EXPR)
5236 error ("%qE is not a valid template argument for type %qT", expr, type);
5237 error ("it must be the address of a function with external linkage");
5241 /* [temp.arg.nontype]/5, bullet 5
5243 For a non-type template-parameter of type reference to function, no
5244 conversions apply. If the template-argument represents a set of
5245 overloaded functions, the matching function is selected from the set
5247 else if (TYPE_REFFN_P (type))
5249 if (TREE_CODE (expr) == ADDR_EXPR)
5251 error ("%qE is not a valid template argument for type %qT "
5252 "because it is a pointer", expr, type);
5253 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5257 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5258 if (!expr || expr == error_mark_node)
5261 expr = build_nop (type, build_address (expr));
5263 /* [temp.arg.nontype]/5, bullet 6
5265 For a non-type template-parameter of type pointer to member function,
5266 no conversions apply. If the template-argument represents a set of
5267 overloaded member functions, the matching member function is selected
5268 from the set (_over.over_). */
5269 else if (TYPE_PTRMEMFUNC_P (type))
5271 expr = instantiate_type (type, expr, tf_none);
5272 if (expr == error_mark_node)
5273 return error_mark_node;
5275 /* [temp.arg.nontype] bullet 1 says the pointer to member
5276 expression must be a pointer-to-member constant. */
5277 if (!check_valid_ptrmem_cst_expr (type, expr))
5278 return error_mark_node;
5280 /* There is no way to disable standard conversions in
5281 resolve_address_of_overloaded_function (called by
5282 instantiate_type). It is possible that the call succeeded by
5283 converting &B::I to &D::I (where B is a base of D), so we need
5284 to reject this conversion here.
5286 Actually, even if there was a way to disable standard conversions,
5287 it would still be better to reject them here so that we can
5288 provide a superior diagnostic. */
5289 if (!same_type_p (TREE_TYPE (expr), type))
5291 error ("%qE is not a valid template argument for type %qT "
5292 "because it is of type %qT", expr, type,
5294 /* If we are just one standard conversion off, explain. */
5295 if (can_convert (type, TREE_TYPE (expr)))
5296 inform (input_location,
5297 "standard conversions are not allowed in this context");
5301 /* [temp.arg.nontype]/5, bullet 7
5303 For a non-type template-parameter of type pointer to data member,
5304 qualification conversions (_conv.qual_) are applied. */
5305 else if (TYPE_PTRMEM_P (type))
5307 /* [temp.arg.nontype] bullet 1 says the pointer to member
5308 expression must be a pointer-to-member constant. */
5309 if (!check_valid_ptrmem_cst_expr (type, expr))
5310 return error_mark_node;
5312 expr = perform_qualification_conversions (type, expr);
5313 if (expr == error_mark_node)
5316 /* A template non-type parameter must be one of the above. */
5320 /* Sanity check: did we actually convert the argument to the
5322 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
5326 /* Subroutine of coerce_template_template_parms, which returns 1 if
5327 PARM_PARM and ARG_PARM match using the rule for the template
5328 parameters of template template parameters. Both PARM and ARG are
5329 template parameters; the rest of the arguments are the same as for
5330 coerce_template_template_parms.
5333 coerce_template_template_parm (tree parm,
5335 tsubst_flags_t complain,
5339 if (arg == NULL_TREE || arg == error_mark_node
5340 || parm == NULL_TREE || parm == error_mark_node)
5343 if (TREE_CODE (arg) != TREE_CODE (parm))
5346 switch (TREE_CODE (parm))
5349 /* We encounter instantiations of templates like
5350 template <template <template <class> class> class TT>
5353 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5354 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5356 if (!coerce_template_template_parms
5357 (parmparm, argparm, complain, in_decl, outer_args))
5363 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5364 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5365 /* Argument is a parameter pack but parameter is not. */
5370 /* The tsubst call is used to handle cases such as
5372 template <int> class C {};
5373 template <class T, template <T> class TT> class D {};
5376 i.e. the parameter list of TT depends on earlier parameters. */
5377 if (!uses_template_parms (TREE_TYPE (arg))
5379 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5383 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5384 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5385 /* Argument is a parameter pack but parameter is not. */
5398 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5399 template template parameters. Both PARM_PARMS and ARG_PARMS are
5400 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5403 Consider the example:
5404 template <class T> class A;
5405 template<template <class U> class TT> class B;
5407 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5408 the parameters to A, and OUTER_ARGS contains A. */
5411 coerce_template_template_parms (tree parm_parms,
5413 tsubst_flags_t complain,
5417 int nparms, nargs, i;
5421 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5422 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5424 nparms = TREE_VEC_LENGTH (parm_parms);
5425 nargs = TREE_VEC_LENGTH (arg_parms);
5427 /* Determine whether we have a parameter pack at the end of the
5428 template template parameter's template parameter list. */
5429 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5431 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5433 if (parm == error_mark_node)
5436 switch (TREE_CODE (parm))
5440 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5445 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5455 && !(variadic_p && nargs >= nparms - 1))
5458 /* Check all of the template parameters except the parameter pack at
5459 the end (if any). */
5460 for (i = 0; i < nparms - variadic_p; ++i)
5462 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5463 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5466 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5467 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5469 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5477 /* Check each of the template parameters in the template
5478 argument against the template parameter pack at the end of
5479 the template template parameter. */
5480 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5483 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5485 for (; i < nargs; ++i)
5487 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5490 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5492 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5501 /* Verifies that the deduced template arguments (in TARGS) for the
5502 template template parameters (in TPARMS) represent valid bindings,
5503 by comparing the template parameter list of each template argument
5504 to the template parameter list of its corresponding template
5505 template parameter, in accordance with DR150. This
5506 routine can only be called after all template arguments have been
5507 deduced. It will return TRUE if all of the template template
5508 parameter bindings are okay, FALSE otherwise. */
5510 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5512 int i, ntparms = TREE_VEC_LENGTH (tparms);
5515 /* We're dealing with template parms in this process. */
5516 ++processing_template_decl;
5518 targs = INNERMOST_TEMPLATE_ARGS (targs);
5520 for (i = 0; i < ntparms; ++i)
5522 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5523 tree targ = TREE_VEC_ELT (targs, i);
5525 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5527 tree packed_args = NULL_TREE;
5530 if (ARGUMENT_PACK_P (targ))
5532 /* Look inside the argument pack. */
5533 packed_args = ARGUMENT_PACK_ARGS (targ);
5534 len = TREE_VEC_LENGTH (packed_args);
5537 for (idx = 0; idx < len; ++idx)
5539 tree targ_parms = NULL_TREE;
5542 /* Extract the next argument from the argument
5544 targ = TREE_VEC_ELT (packed_args, idx);
5546 if (PACK_EXPANSION_P (targ))
5547 /* Look at the pattern of the pack expansion. */
5548 targ = PACK_EXPANSION_PATTERN (targ);
5550 /* Extract the template parameters from the template
5552 if (TREE_CODE (targ) == TEMPLATE_DECL)
5553 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5554 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5555 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5557 /* Verify that we can coerce the template template
5558 parameters from the template argument to the template
5559 parameter. This requires an exact match. */
5561 && !coerce_template_template_parms
5562 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5577 --processing_template_decl;
5581 /* Convert the indicated template ARG as necessary to match the
5582 indicated template PARM. Returns the converted ARG, or
5583 error_mark_node if the conversion was unsuccessful. Error and
5584 warning messages are issued under control of COMPLAIN. This
5585 conversion is for the Ith parameter in the parameter list. ARGS is
5586 the full set of template arguments deduced so far. */
5589 convert_template_argument (tree parm,
5592 tsubst_flags_t complain,
5598 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5600 if (TREE_CODE (arg) == TREE_LIST
5601 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5603 /* The template argument was the name of some
5604 member function. That's usually
5605 invalid, but static members are OK. In any
5606 case, grab the underlying fields/functions
5607 and issue an error later if required. */
5608 orig_arg = TREE_VALUE (arg);
5609 TREE_TYPE (arg) = unknown_type_node;
5614 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5615 requires_type = (TREE_CODE (parm) == TYPE_DECL
5616 || requires_tmpl_type);
5618 /* When determining whether an argument pack expansion is a template,
5619 look at the pattern. */
5620 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5621 arg = PACK_EXPANSION_PATTERN (arg);
5623 /* Deal with an injected-class-name used as a template template arg. */
5624 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5626 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5627 if (TREE_CODE (t) == TEMPLATE_DECL)
5629 if (complain & tf_warning_or_error)
5630 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5631 " used as template template argument", TYPE_NAME (arg));
5632 else if (flag_pedantic_errors)
5640 ((TREE_CODE (arg) == TEMPLATE_DECL
5641 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5642 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5643 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5646 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5647 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5648 arg = TYPE_STUB_DECL (arg);
5650 is_type = TYPE_P (arg) || is_tmpl_type;
5652 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5653 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5655 permerror (input_location, "to refer to a type member of a template parameter, "
5656 "use %<typename %E%>", orig_arg);
5658 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5659 TREE_OPERAND (arg, 1),
5661 complain & tf_error);
5665 if (is_type != requires_type)
5669 if (complain & tf_error)
5671 error ("type/value mismatch at argument %d in template "
5672 "parameter list for %qD",
5675 error (" expected a constant of type %qT, got %qT",
5677 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5678 else if (requires_tmpl_type)
5679 error (" expected a class template, got %qE", orig_arg);
5681 error (" expected a type, got %qE", orig_arg);
5684 return error_mark_node;
5686 if (is_tmpl_type ^ requires_tmpl_type)
5688 if (in_decl && (complain & tf_error))
5690 error ("type/value mismatch at argument %d in template "
5691 "parameter list for %qD",
5694 error (" expected a type, got %qT", DECL_NAME (arg));
5696 error (" expected a class template, got %qT", orig_arg);
5698 return error_mark_node;
5703 if (requires_tmpl_type)
5705 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5706 /* The number of argument required is not known yet.
5707 Just accept it for now. */
5708 val = TREE_TYPE (arg);
5711 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5714 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5716 if (coerce_template_template_parms (parmparm, argparm,
5722 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5724 if (val != error_mark_node)
5726 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5727 val = TREE_TYPE (val);
5728 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
5729 val = make_pack_expansion (val);
5734 if (in_decl && (complain & tf_error))
5736 error ("type/value mismatch at argument %d in "
5737 "template parameter list for %qD",
5739 error (" expected a template of type %qD, got %qT",
5743 val = error_mark_node;
5749 /* We only form one instance of each template specialization.
5750 Therefore, if we use a non-canonical variant (i.e., a
5751 typedef), any future messages referring to the type will use
5752 the typedef, which is confusing if those future uses do not
5753 themselves also use the typedef. */
5755 val = strip_typedefs (val);
5759 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5761 if (invalid_nontype_parm_type_p (t, complain))
5762 return error_mark_node;
5764 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5766 if (same_type_p (t, TREE_TYPE (orig_arg)))
5770 /* Not sure if this is reachable, but it doesn't hurt
5772 error ("type mismatch in nontype parameter pack");
5773 val = error_mark_node;
5776 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5777 /* We used to call digest_init here. However, digest_init
5778 will report errors, which we don't want when complain
5779 is zero. More importantly, digest_init will try too
5780 hard to convert things: for example, `0' should not be
5781 converted to pointer type at this point according to
5782 the standard. Accepting this is not merely an
5783 extension, since deciding whether or not these
5784 conversions can occur is part of determining which
5785 function template to call, or whether a given explicit
5786 argument specification is valid. */
5787 val = convert_nontype_argument (t, orig_arg);
5791 if (val == NULL_TREE)
5792 val = error_mark_node;
5793 else if (val == error_mark_node && (complain & tf_error))
5794 error ("could not convert template argument %qE to %qT", orig_arg, t);
5796 if (TREE_CODE (val) == SCOPE_REF)
5798 /* Strip typedefs from the SCOPE_REF. */
5799 tree type = strip_typedefs (TREE_TYPE (val));
5800 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
5801 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
5802 QUALIFIED_NAME_IS_TEMPLATE (val));
5809 /* Coerces the remaining template arguments in INNER_ARGS (from
5810 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5811 Returns the coerced argument pack. PARM_IDX is the position of this
5812 parameter in the template parameter list. ARGS is the original
5813 template argument list. */
5815 coerce_template_parameter_pack (tree parms,
5823 tsubst_flags_t complain)
5825 tree parm = TREE_VEC_ELT (parms, parm_idx);
5826 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5829 tree packed_types = NULL_TREE;
5831 if (arg_idx > nargs)
5834 packed_args = make_tree_vec (nargs - arg_idx);
5836 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5837 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5839 /* When the template parameter is a non-type template
5840 parameter pack whose type uses parameter packs, we need
5841 to look at each of the template arguments
5842 separately. Build a vector of the types for these
5843 non-type template parameters in PACKED_TYPES. */
5845 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5846 packed_types = tsubst_pack_expansion (expansion, args,
5849 if (packed_types == error_mark_node)
5850 return error_mark_node;
5852 /* Check that we have the right number of arguments. */
5854 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5855 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5858 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5859 error ("wrong number of template arguments (%d, should be %d)",
5860 nargs, needed_parms);
5861 return error_mark_node;
5864 /* If we aren't able to check the actual arguments now
5865 (because they haven't been expanded yet), we can at least
5866 verify that all of the types used for the non-type
5867 template parameter pack are, in fact, valid for non-type
5868 template parameters. */
5870 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5872 int j, len = TREE_VEC_LENGTH (packed_types);
5873 for (j = 0; j < len; ++j)
5875 tree t = TREE_VEC_ELT (packed_types, j);
5876 if (invalid_nontype_parm_type_p (t, complain))
5877 return error_mark_node;
5882 /* Convert the remaining arguments, which will be a part of the
5883 parameter pack "parm". */
5884 for (; arg_idx < nargs; ++arg_idx)
5886 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5887 tree actual_parm = TREE_VALUE (parm);
5889 if (packed_types && !PACK_EXPANSION_P (arg))
5891 /* When we have a vector of types (corresponding to the
5892 non-type template parameter pack that uses parameter
5893 packs in its type, as mention above), and the
5894 argument is not an expansion (which expands to a
5895 currently unknown number of arguments), clone the
5896 parm and give it the next type in PACKED_TYPES. */
5897 actual_parm = copy_node (actual_parm);
5898 TREE_TYPE (actual_parm) =
5899 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5902 if (arg != error_mark_node)
5903 arg = convert_template_argument (actual_parm,
5904 arg, new_args, complain, parm_idx,
5906 if (arg == error_mark_node)
5908 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5911 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5912 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5913 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
5916 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5917 TREE_TYPE (argument_pack)
5918 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5919 TREE_CONSTANT (argument_pack) = 1;
5922 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5923 #ifdef ENABLE_CHECKING
5924 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
5925 TREE_VEC_LENGTH (packed_args));
5927 return argument_pack;
5930 /* Convert all template arguments to their appropriate types, and
5931 return a vector containing the innermost resulting template
5932 arguments. If any error occurs, return error_mark_node. Error and
5933 warning messages are issued under control of COMPLAIN.
5935 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5936 for arguments not specified in ARGS. Otherwise, if
5937 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5938 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5939 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5943 coerce_template_parms (tree parms,
5946 tsubst_flags_t complain,
5947 bool require_all_args,
5948 bool use_default_args)
5950 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5953 tree new_inner_args;
5954 int saved_unevaluated_operand;
5955 int saved_inhibit_evaluation_warnings;
5957 /* When used as a boolean value, indicates whether this is a
5958 variadic template parameter list. Since it's an int, we can also
5959 subtract it from nparms to get the number of non-variadic
5963 nparms = TREE_VEC_LENGTH (parms);
5965 /* Determine if there are any parameter packs. */
5966 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5968 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5969 if (template_parameter_pack_p (tparm))
5973 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5974 /* If there are 0 or 1 parameter packs, we need to expand any argument
5975 packs so that we can deduce a parameter pack from some non-packed args
5976 followed by an argument pack, as in variadic85.C. If there are more
5977 than that, we need to leave argument packs intact so the arguments are
5978 assigned to the right parameter packs. This should only happen when
5979 dealing with a nested class inside a partial specialization of a class
5980 template, as in variadic92.C. */
5981 if (variadic_p <= 1)
5982 inner_args = expand_template_argument_pack (inner_args);
5984 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5985 if ((nargs > nparms && !variadic_p)
5986 || (nargs < nparms - variadic_p
5988 && (!use_default_args
5989 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5990 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5992 if (complain & tf_error)
5997 error ("wrong number of template arguments "
5998 "(%d, should be %d or more)", nargs, nparms);
6001 error ("wrong number of template arguments "
6002 "(%d, should be %d)", nargs, nparms);
6005 error ("provided for %q+D", in_decl);
6008 return error_mark_node;
6011 /* We need to evaluate the template arguments, even though this
6012 template-id may be nested within a "sizeof". */
6013 saved_unevaluated_operand = cp_unevaluated_operand;
6014 cp_unevaluated_operand = 0;
6015 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6016 c_inhibit_evaluation_warnings = 0;
6017 new_inner_args = make_tree_vec (nparms);
6018 new_args = add_outermost_template_args (args, new_inner_args);
6019 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6024 /* Get the Ith template parameter. */
6025 parm = TREE_VEC_ELT (parms, parm_idx);
6027 if (parm == error_mark_node)
6029 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6033 /* Calculate the next argument. */
6034 if (arg_idx < nargs)
6035 arg = TREE_VEC_ELT (inner_args, arg_idx);
6039 if (template_parameter_pack_p (TREE_VALUE (parm))
6040 && !(arg && ARGUMENT_PACK_P (arg)))
6042 /* All remaining arguments will be placed in the
6043 template parameter pack PARM. */
6044 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6045 inner_args, arg_idx,
6049 /* Store this argument. */
6050 if (arg == error_mark_node)
6052 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6054 /* We are done with all of the arguments. */
6061 if (PACK_EXPANSION_P (arg))
6063 if (complain & tf_error)
6065 /* FIXME this restriction was removed by N2555; see
6067 /* If ARG is a pack expansion, but PARM is not a
6068 template parameter pack (if it were, we would have
6069 handled it above), we're trying to expand into a
6070 fixed-length argument list. */
6071 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6072 sorry ("cannot expand %<%E%> into a fixed-length "
6073 "argument list", arg);
6075 sorry ("cannot expand %<%T%> into a fixed-length "
6076 "argument list", arg);
6078 return error_mark_node;
6081 else if (require_all_args)
6083 /* There must be a default arg in this case. */
6084 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6086 /* The position of the first default template argument,
6087 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6089 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6090 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6095 if (arg == error_mark_node)
6097 if (complain & tf_error)
6098 error ("template argument %d is invalid", arg_idx + 1);
6101 /* This only occurs if there was an error in the template
6102 parameter list itself (which we would already have
6103 reported) that we are trying to recover from, e.g., a class
6104 template with a parameter list such as
6105 template<typename..., typename>. */
6106 return error_mark_node;
6108 arg = convert_template_argument (TREE_VALUE (parm),
6109 arg, new_args, complain,
6112 if (arg == error_mark_node)
6114 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6116 cp_unevaluated_operand = saved_unevaluated_operand;
6117 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6120 return error_mark_node;
6122 #ifdef ENABLE_CHECKING
6123 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6124 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6125 TREE_VEC_LENGTH (new_inner_args));
6128 return new_inner_args;
6131 /* Returns 1 if template args OT and NT are equivalent. */
6134 template_args_equal (tree ot, tree nt)
6139 if (TREE_CODE (nt) == TREE_VEC)
6140 /* For member templates */
6141 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6142 else if (PACK_EXPANSION_P (ot))
6143 return PACK_EXPANSION_P (nt)
6144 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6145 PACK_EXPANSION_PATTERN (nt));
6146 else if (ARGUMENT_PACK_P (ot))
6151 if (!ARGUMENT_PACK_P (nt))
6154 opack = ARGUMENT_PACK_ARGS (ot);
6155 npack = ARGUMENT_PACK_ARGS (nt);
6156 len = TREE_VEC_LENGTH (opack);
6157 if (TREE_VEC_LENGTH (npack) != len)
6159 for (i = 0; i < len; ++i)
6160 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6161 TREE_VEC_ELT (npack, i)))
6165 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6167 /* We get here probably because we are in the middle of substituting
6168 into the pattern of a pack expansion. In that case the
6169 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6170 interested in. So we want to use the initial pack argument for
6172 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6173 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6174 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6175 return template_args_equal (ot, nt);
6177 else if (TYPE_P (nt))
6178 return TYPE_P (ot) && same_type_p (ot, nt);
6179 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6182 return cp_tree_equal (ot, nt);
6185 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6186 of template arguments. Returns 0 otherwise. */
6189 comp_template_args (tree oldargs, tree newargs)
6193 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6196 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6198 tree nt = TREE_VEC_ELT (newargs, i);
6199 tree ot = TREE_VEC_ELT (oldargs, i);
6201 if (! template_args_equal (ot, nt))
6208 add_pending_template (tree d)
6210 tree ti = (TYPE_P (d)
6211 ? CLASSTYPE_TEMPLATE_INFO (d)
6212 : DECL_TEMPLATE_INFO (d));
6213 struct pending_template *pt;
6216 if (TI_PENDING_TEMPLATE_FLAG (ti))
6219 /* We are called both from instantiate_decl, where we've already had a
6220 tinst_level pushed, and instantiate_template, where we haven't.
6222 level = !current_tinst_level || current_tinst_level->decl != d;
6225 push_tinst_level (d);
6227 pt = ggc_alloc_pending_template ();
6229 pt->tinst = current_tinst_level;
6230 if (last_pending_template)
6231 last_pending_template->next = pt;
6233 pending_templates = pt;
6235 last_pending_template = pt;
6237 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6244 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6245 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6246 documentation for TEMPLATE_ID_EXPR. */
6249 lookup_template_function (tree fns, tree arglist)
6253 if (fns == error_mark_node || arglist == error_mark_node)
6254 return error_mark_node;
6256 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6257 gcc_assert (fns && (is_overloaded_fn (fns)
6258 || TREE_CODE (fns) == IDENTIFIER_NODE));
6260 if (BASELINK_P (fns))
6262 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6264 BASELINK_FUNCTIONS (fns),
6269 type = TREE_TYPE (fns);
6270 if (TREE_CODE (fns) == OVERLOAD || !type)
6271 type = unknown_type_node;
6273 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6276 /* Within the scope of a template class S<T>, the name S gets bound
6277 (in build_self_reference) to a TYPE_DECL for the class, not a
6278 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6279 or one of its enclosing classes, and that type is a template,
6280 return the associated TEMPLATE_DECL. Otherwise, the original
6283 Also handle the case when DECL is a TREE_LIST of ambiguous
6284 injected-class-names from different bases. */
6287 maybe_get_template_decl_from_type_decl (tree decl)
6289 if (decl == NULL_TREE)
6292 /* DR 176: A lookup that finds an injected-class-name (10.2
6293 [class.member.lookup]) can result in an ambiguity in certain cases
6294 (for example, if it is found in more than one base class). If all of
6295 the injected-class-names that are found refer to specializations of
6296 the same class template, and if the name is followed by a
6297 template-argument-list, the reference refers to the class template
6298 itself and not a specialization thereof, and is not ambiguous. */
6299 if (TREE_CODE (decl) == TREE_LIST)
6301 tree t, tmpl = NULL_TREE;
6302 for (t = decl; t; t = TREE_CHAIN (t))
6304 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6307 else if (tmpl != elt)
6310 if (tmpl && t == NULL_TREE)
6316 return (decl != NULL_TREE
6317 && DECL_SELF_REFERENCE_P (decl)
6318 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6319 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6322 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6323 parameters, find the desired type.
6325 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6327 IN_DECL, if non-NULL, is the template declaration we are trying to
6330 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6331 the class we are looking up.
6333 Issue error and warning messages under control of COMPLAIN.
6335 If the template class is really a local class in a template
6336 function, then the FUNCTION_CONTEXT is the function in which it is
6339 ??? Note that this function is currently called *twice* for each
6340 template-id: the first time from the parser, while creating the
6341 incomplete type (finish_template_type), and the second type during the
6342 real instantiation (instantiate_template_class). This is surely something
6343 that we want to avoid. It also causes some problems with argument
6344 coercion (see convert_nontype_argument for more information on this). */
6347 lookup_template_class (tree d1,
6352 tsubst_flags_t complain)
6354 tree templ = NULL_TREE, parmlist;
6361 timevar_push (TV_NAME_LOOKUP);
6363 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6365 tree value = innermost_non_namespace_value (d1);
6366 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6371 push_decl_namespace (context);
6372 templ = lookup_name (d1);
6373 templ = maybe_get_template_decl_from_type_decl (templ);
6375 pop_decl_namespace ();
6378 context = DECL_CONTEXT (templ);
6380 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6382 tree type = TREE_TYPE (d1);
6384 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6385 an implicit typename for the second A. Deal with it. */
6386 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6387 type = TREE_TYPE (type);
6389 if (CLASSTYPE_TEMPLATE_INFO (type))
6391 templ = CLASSTYPE_TI_TEMPLATE (type);
6392 d1 = DECL_NAME (templ);
6395 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6396 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6398 templ = TYPE_TI_TEMPLATE (d1);
6399 d1 = DECL_NAME (templ);
6401 else if (TREE_CODE (d1) == TEMPLATE_DECL
6402 && DECL_TEMPLATE_RESULT (d1)
6403 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6406 d1 = DECL_NAME (templ);
6407 context = DECL_CONTEXT (templ);
6410 /* Issue an error message if we didn't find a template. */
6413 if (complain & tf_error)
6414 error ("%qT is not a template", d1);
6415 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6418 if (TREE_CODE (templ) != TEMPLATE_DECL
6419 /* Make sure it's a user visible template, if it was named by
6421 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6422 && !PRIMARY_TEMPLATE_P (templ)))
6424 if (complain & tf_error)
6426 error ("non-template type %qT used as a template", d1);
6428 error ("for template declaration %q+D", in_decl);
6430 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6433 complain &= ~tf_user;
6435 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6437 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6438 template arguments */
6444 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6446 /* Consider an example where a template template parameter declared as
6448 template <class T, class U = std::allocator<T> > class TT
6450 The template parameter level of T and U are one level larger than
6451 of TT. To proper process the default argument of U, say when an
6452 instantiation `TT<int>' is seen, we need to build the full
6453 arguments containing {int} as the innermost level. Outer levels,
6454 available when not appearing as default template argument, can be
6455 obtained from the arguments of the enclosing template.
6457 Suppose that TT is later substituted with std::vector. The above
6458 instantiation is `TT<int, std::allocator<T> >' with TT at
6459 level 1, and T at level 2, while the template arguments at level 1
6460 becomes {std::vector} and the inner level 2 is {int}. */
6462 outer = DECL_CONTEXT (templ);
6464 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6465 else if (current_template_parms)
6466 /* This is an argument of the current template, so we haven't set
6467 DECL_CONTEXT yet. */
6468 outer = current_template_args ();
6471 arglist = add_to_template_args (outer, arglist);
6473 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6475 /*require_all_args=*/true,
6476 /*use_default_args=*/true);
6477 if (arglist2 == error_mark_node
6478 || (!uses_template_parms (arglist2)
6479 && check_instantiated_args (templ, arglist2, complain)))
6480 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6482 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6483 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6487 tree template_type = TREE_TYPE (templ);
6490 tree found = NULL_TREE;
6493 int is_dependent_type;
6494 int use_partial_inst_tmpl = false;
6496 gen_tmpl = most_general_template (templ);
6497 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6498 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6499 arg_depth = TMPL_ARGS_DEPTH (arglist);
6501 if (arg_depth == 1 && parm_depth > 1)
6503 /* We've been given an incomplete set of template arguments.
6506 template <class T> struct S1 {
6507 template <class U> struct S2 {};
6508 template <class U> struct S2<U*> {};
6511 we will be called with an ARGLIST of `U*', but the
6512 TEMPLATE will be `template <class T> template
6513 <class U> struct S1<T>::S2'. We must fill in the missing
6516 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6518 arg_depth = TMPL_ARGS_DEPTH (arglist);
6521 /* Now we should have enough arguments. */
6522 gcc_assert (parm_depth == arg_depth);
6524 /* From here on, we're only interested in the most general
6527 /* Calculate the BOUND_ARGS. These will be the args that are
6528 actually tsubst'd into the definition to create the
6532 /* We have multiple levels of arguments to coerce, at once. */
6534 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6536 tree bound_args = make_tree_vec (parm_depth);
6538 for (i = saved_depth,
6539 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6540 i > 0 && t != NULL_TREE;
6541 --i, t = TREE_CHAIN (t))
6544 if (i == saved_depth)
6545 a = coerce_template_parms (TREE_VALUE (t),
6548 /*require_all_args=*/true,
6549 /*use_default_args=*/true);
6551 /* Outer levels should have already been coerced. */
6552 a = TMPL_ARGS_LEVEL (arglist, i);
6554 /* Don't process further if one of the levels fails. */
6555 if (a == error_mark_node)
6557 /* Restore the ARGLIST to its full size. */
6558 TREE_VEC_LENGTH (arglist) = saved_depth;
6559 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6562 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6564 /* We temporarily reduce the length of the ARGLIST so
6565 that coerce_template_parms will see only the arguments
6566 corresponding to the template parameters it is
6568 TREE_VEC_LENGTH (arglist)--;
6571 /* Restore the ARGLIST to its full size. */
6572 TREE_VEC_LENGTH (arglist) = saved_depth;
6574 arglist = bound_args;
6578 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6579 INNERMOST_TEMPLATE_ARGS (arglist),
6582 /*require_all_args=*/true,
6583 /*use_default_args=*/true);
6585 if (arglist == error_mark_node)
6586 /* We were unable to bind the arguments. */
6587 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6589 /* In the scope of a template class, explicit references to the
6590 template class refer to the type of the template, not any
6591 instantiation of it. For example, in:
6593 template <class T> class C { void f(C<T>); }
6595 the `C<T>' is just the same as `C'. Outside of the
6596 class, however, such a reference is an instantiation. */
6598 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6599 || currently_open_class (template_type))
6600 /* comp_template_args is expensive, check it last. */
6601 && comp_template_args (TYPE_TI_ARGS (template_type),
6603 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6605 /* If we already have this specialization, return it. */
6606 elt.tmpl = gen_tmpl;
6608 hash = hash_specialization (&elt);
6609 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6613 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6615 is_dependent_type = uses_template_parms (arglist);
6617 /* If the deduced arguments are invalid, then the binding
6619 if (!is_dependent_type
6620 && check_instantiated_args (gen_tmpl,
6621 INNERMOST_TEMPLATE_ARGS (arglist),
6623 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6625 if (!is_dependent_type
6626 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6627 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6628 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6630 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6631 DECL_NAME (gen_tmpl),
6632 /*tag_scope=*/ts_global);
6633 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6636 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6639 context = global_namespace;
6641 /* Create the type. */
6642 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6644 if (!is_dependent_type)
6646 set_current_access_from_decl (TYPE_NAME (template_type));
6647 t = start_enum (TYPE_IDENTIFIER (template_type),
6648 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6649 arglist, complain, in_decl),
6650 SCOPED_ENUM_P (template_type));
6654 /* We don't want to call start_enum for this type, since
6655 the values for the enumeration constants may involve
6656 template parameters. And, no one should be interested
6657 in the enumeration constants for such a type. */
6658 t = cxx_make_type (ENUMERAL_TYPE);
6659 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6664 t = make_class_type (TREE_CODE (template_type));
6665 CLASSTYPE_DECLARED_CLASS (t)
6666 = CLASSTYPE_DECLARED_CLASS (template_type);
6667 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6668 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6670 /* A local class. Make sure the decl gets registered properly. */
6671 if (context == current_function_decl)
6672 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6674 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6675 /* This instantiation is another name for the primary
6676 template type. Set the TYPE_CANONICAL field
6678 TYPE_CANONICAL (t) = template_type;
6679 else if (any_template_arguments_need_structural_equality_p (arglist))
6680 /* Some of the template arguments require structural
6681 equality testing, so this template class requires
6682 structural equality testing. */
6683 SET_TYPE_STRUCTURAL_EQUALITY (t);
6686 /* If we called start_enum or pushtag above, this information
6687 will already be set up. */
6690 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6692 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6693 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6694 DECL_SOURCE_LOCATION (type_decl)
6695 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6698 type_decl = TYPE_NAME (t);
6700 TREE_PRIVATE (type_decl)
6701 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6702 TREE_PROTECTED (type_decl)
6703 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6704 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6706 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6707 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6710 /* Let's consider the explicit specialization of a member
6711 of a class template specialization that is implicitely instantiated,
6716 template<class U> struct M {}; //#0
6721 struct S<int>::M<char> //#1
6725 [temp.expl.spec]/4 says this is valid.
6727 In this case, when we write:
6730 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
6733 When we encounter #1, we want to store the partial instantiation
6734 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
6736 For all cases other than this "explicit specialization of member of a
6737 class template", we just want to store the most general template into
6738 the CLASSTYPE_TI_TEMPLATE of M.
6740 This case of "explicit specialization of member of a class template"
6742 1/ the enclosing class is an instantiation of, and therefore not
6743 the same as, the context of the most general template, and
6744 2/ we aren't looking at the partial instantiation itself, i.e.
6745 the innermost arguments are not the same as the innermost parms of
6746 the most general template.
6748 So it's only when 1/ and 2/ happens that we want to use the partial
6749 instantiation of the member template in lieu of its most general
6752 if (PRIMARY_TEMPLATE_P (gen_tmpl)
6753 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
6754 /* the enclosing class must be an instantiation... */
6755 && CLASS_TYPE_P (context)
6756 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
6758 tree partial_inst_args;
6759 TREE_VEC_LENGTH (arglist)--;
6760 ++processing_template_decl;
6762 tsubst (INNERMOST_TEMPLATE_ARGS
6763 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
6764 arglist, complain, NULL_TREE);
6765 --processing_template_decl;
6766 TREE_VEC_LENGTH (arglist)++;
6767 use_partial_inst_tmpl =
6768 /*...and we must not be looking at the partial instantiation
6770 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
6774 if (!use_partial_inst_tmpl)
6775 /* This case is easy; there are no member templates involved. */
6779 /* This is a full instantiation of a member template. Find
6780 the partial instantiation of which this is an instance. */
6782 /* Temporarily reduce by one the number of levels in the ARGLIST
6783 so as to avoid comparing the last set of arguments. */
6784 TREE_VEC_LENGTH (arglist)--;
6785 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6786 TREE_VEC_LENGTH (arglist)++;
6787 found = CLASSTYPE_TI_TEMPLATE (found);
6790 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
6793 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6794 &elt, hash, INSERT);
6795 *slot = ggc_alloc_spec_entry ();
6798 /* Note this use of the partial instantiation so we can check it
6799 later in maybe_process_partial_specialization. */
6800 DECL_TEMPLATE_INSTANTIATIONS (templ)
6801 = tree_cons (arglist, t,
6802 DECL_TEMPLATE_INSTANTIATIONS (templ));
6804 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
6805 /* Now that the type has been registered on the instantiations
6806 list, we set up the enumerators. Because the enumeration
6807 constants may involve the enumeration type itself, we make
6808 sure to register the type first, and then create the
6809 constants. That way, doing tsubst_expr for the enumeration
6810 constants won't result in recursive calls here; we'll find
6811 the instantiation and exit above. */
6812 tsubst_enum (template_type, t, arglist);
6814 if (is_dependent_type)
6815 /* If the type makes use of template parameters, the
6816 code that generates debugging information will crash. */
6817 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6819 /* Possibly limit visibility based on template args. */
6820 TREE_PUBLIC (type_decl) = 1;
6821 determine_visibility (type_decl);
6823 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6825 timevar_pop (TV_NAME_LOOKUP);
6832 /* True when we should also visit template parameters that occur in
6833 non-deduced contexts. */
6834 bool include_nondeduced_p;
6835 struct pointer_set_t *visited;
6838 /* Called from for_each_template_parm via walk_tree. */
6841 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6844 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6845 tree_fn_t fn = pfd->fn;
6846 void *data = pfd->data;
6849 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6850 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6851 pfd->include_nondeduced_p))
6852 return error_mark_node;
6854 switch (TREE_CODE (t))
6857 if (TYPE_PTRMEMFUNC_P (t))
6863 if (!TYPE_TEMPLATE_INFO (t))
6865 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
6866 fn, data, pfd->visited,
6867 pfd->include_nondeduced_p))
6868 return error_mark_node;
6872 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6873 fn, data, pfd->visited,
6874 pfd->include_nondeduced_p)
6875 || for_each_template_parm (TYPE_MAX_VALUE (t),
6876 fn, data, pfd->visited,
6877 pfd->include_nondeduced_p))
6878 return error_mark_node;
6882 /* Since we're not going to walk subtrees, we have to do this
6884 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6885 pfd->visited, pfd->include_nondeduced_p))
6886 return error_mark_node;
6890 /* Check the return type. */
6891 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6892 pfd->include_nondeduced_p))
6893 return error_mark_node;
6895 /* Check the parameter types. Since default arguments are not
6896 instantiated until they are needed, the TYPE_ARG_TYPES may
6897 contain expressions that involve template parameters. But,
6898 no-one should be looking at them yet. And, once they're
6899 instantiated, they don't contain template parameters, so
6900 there's no point in looking at them then, either. */
6904 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6905 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6906 pfd->visited, pfd->include_nondeduced_p))
6907 return error_mark_node;
6909 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6910 want walk_tree walking into them itself. */
6916 if (pfd->include_nondeduced_p
6917 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6919 pfd->include_nondeduced_p))
6920 return error_mark_node;
6925 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6926 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6927 pfd->visited, pfd->include_nondeduced_p))
6928 return error_mark_node;
6933 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6934 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6935 pfd->visited, pfd->include_nondeduced_p))
6936 return error_mark_node;
6937 if (DECL_CONTEXT (t)
6938 && pfd->include_nondeduced_p
6939 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6940 pfd->visited, pfd->include_nondeduced_p))
6941 return error_mark_node;
6944 case BOUND_TEMPLATE_TEMPLATE_PARM:
6945 /* Record template parameters such as `T' inside `TT<T>'. */
6946 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6947 pfd->include_nondeduced_p))
6948 return error_mark_node;
6951 case TEMPLATE_TEMPLATE_PARM:
6952 case TEMPLATE_TYPE_PARM:
6953 case TEMPLATE_PARM_INDEX:
6954 if (fn && (*fn)(t, data))
6955 return error_mark_node;
6957 return error_mark_node;
6961 /* A template template parameter is encountered. */
6962 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6963 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6964 pfd->include_nondeduced_p))
6965 return error_mark_node;
6967 /* Already substituted template template parameter */
6973 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6975 pfd->include_nondeduced_p))
6976 return error_mark_node;
6980 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6981 && pfd->include_nondeduced_p
6982 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6983 (TREE_TYPE (t)), fn, data,
6984 pfd->visited, pfd->include_nondeduced_p))
6985 return error_mark_node;
6990 /* If there's no type, then this thing must be some expression
6991 involving template parameters. */
6992 if (!fn && !TREE_TYPE (t))
6993 return error_mark_node;
6998 case REINTERPRET_CAST_EXPR:
6999 case CONST_CAST_EXPR:
7000 case STATIC_CAST_EXPR:
7001 case DYNAMIC_CAST_EXPR:
7005 case PSEUDO_DTOR_EXPR:
7007 return error_mark_node;
7014 /* We didn't find any template parameters we liked. */
7018 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7019 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7020 call FN with the parameter and the DATA.
7021 If FN returns nonzero, the iteration is terminated, and
7022 for_each_template_parm returns 1. Otherwise, the iteration
7023 continues. If FN never returns a nonzero value, the value
7024 returned by for_each_template_parm is 0. If FN is NULL, it is
7025 considered to be the function which always returns 1.
7027 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7028 parameters that occur in non-deduced contexts. When false, only
7029 visits those template parameters that can be deduced. */
7032 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7033 struct pointer_set_t *visited,
7034 bool include_nondeduced_p)
7036 struct pair_fn_data pfd;
7042 pfd.include_nondeduced_p = include_nondeduced_p;
7044 /* Walk the tree. (Conceptually, we would like to walk without
7045 duplicates, but for_each_template_parm_r recursively calls
7046 for_each_template_parm, so we would need to reorganize a fair
7047 bit to use walk_tree_without_duplicates, so we keep our own
7050 pfd.visited = visited;
7052 pfd.visited = pointer_set_create ();
7053 result = cp_walk_tree (&t,
7054 for_each_template_parm_r,
7056 pfd.visited) != NULL_TREE;
7061 pointer_set_destroy (pfd.visited);
7068 /* Returns true if T depends on any template parameter. */
7071 uses_template_parms (tree t)
7074 int saved_processing_template_decl;
7076 saved_processing_template_decl = processing_template_decl;
7077 if (!saved_processing_template_decl)
7078 processing_template_decl = 1;
7080 dependent_p = dependent_type_p (t);
7081 else if (TREE_CODE (t) == TREE_VEC)
7082 dependent_p = any_dependent_template_arguments_p (t);
7083 else if (TREE_CODE (t) == TREE_LIST)
7084 dependent_p = (uses_template_parms (TREE_VALUE (t))
7085 || uses_template_parms (TREE_CHAIN (t)));
7086 else if (TREE_CODE (t) == TYPE_DECL)
7087 dependent_p = dependent_type_p (TREE_TYPE (t));
7090 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7091 || TREE_CODE (t) == OVERLOAD
7092 || TREE_CODE (t) == BASELINK
7093 || TREE_CODE (t) == IDENTIFIER_NODE
7094 || TREE_CODE (t) == TRAIT_EXPR
7095 || TREE_CODE (t) == CONSTRUCTOR
7096 || CONSTANT_CLASS_P (t))
7097 dependent_p = (type_dependent_expression_p (t)
7098 || value_dependent_expression_p (t));
7101 gcc_assert (t == error_mark_node);
7102 dependent_p = false;
7105 processing_template_decl = saved_processing_template_decl;
7110 /* Returns true if T depends on any template parameter with level LEVEL. */
7113 uses_template_parms_level (tree t, int level)
7115 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7116 /*include_nondeduced_p=*/true);
7119 static int tinst_depth;
7120 extern int max_tinst_depth;
7121 #ifdef GATHER_STATISTICS
7124 static int tinst_level_tick;
7125 static int last_template_error_tick;
7127 /* We're starting to instantiate D; record the template instantiation context
7128 for diagnostics and to restore it later. */
7131 push_tinst_level (tree d)
7133 struct tinst_level *new_level;
7135 if (tinst_depth >= max_tinst_depth)
7137 /* If the instantiation in question still has unbound template parms,
7138 we don't really care if we can't instantiate it, so just return.
7139 This happens with base instantiation for implicit `typename'. */
7140 if (uses_template_parms (d))
7143 last_template_error_tick = tinst_level_tick;
7144 error ("template instantiation depth exceeds maximum of %d (use "
7145 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7146 max_tinst_depth, d);
7148 print_instantiation_context ();
7153 new_level = ggc_alloc_tinst_level ();
7154 new_level->decl = d;
7155 new_level->locus = input_location;
7156 new_level->in_system_header_p = in_system_header;
7157 new_level->next = current_tinst_level;
7158 current_tinst_level = new_level;
7161 #ifdef GATHER_STATISTICS
7162 if (tinst_depth > depth_reached)
7163 depth_reached = tinst_depth;
7170 /* We're done instantiating this template; return to the instantiation
7174 pop_tinst_level (void)
7176 /* Restore the filename and line number stashed away when we started
7177 this instantiation. */
7178 input_location = current_tinst_level->locus;
7179 current_tinst_level = current_tinst_level->next;
7184 /* We're instantiating a deferred template; restore the template
7185 instantiation context in which the instantiation was requested, which
7186 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7189 reopen_tinst_level (struct tinst_level *level)
7191 struct tinst_level *t;
7194 for (t = level; t; t = t->next)
7197 current_tinst_level = level;
7202 /* Returns the TINST_LEVEL which gives the original instantiation
7205 struct tinst_level *
7206 outermost_tinst_level (void)
7208 struct tinst_level *level = current_tinst_level;
7211 level = level->next;
7215 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7218 parameter_of_template_p (tree parm, tree templ)
7223 if (!parm || !templ)
7226 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7227 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7229 parms = DECL_TEMPLATE_PARMS (templ);
7230 parms = INNERMOST_TEMPLATE_PARMS (parms);
7232 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7233 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7239 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7240 vector of template arguments, as for tsubst.
7242 Returns an appropriate tsubst'd friend declaration. */
7245 tsubst_friend_function (tree decl, tree args)
7249 if (TREE_CODE (decl) == FUNCTION_DECL
7250 && DECL_TEMPLATE_INSTANTIATION (decl)
7251 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7252 /* This was a friend declared with an explicit template
7253 argument list, e.g.:
7257 to indicate that f was a template instantiation, not a new
7258 function declaration. Now, we have to figure out what
7259 instantiation of what template. */
7261 tree template_id, arglist, fns;
7264 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7266 /* Friend functions are looked up in the containing namespace scope.
7267 We must enter that scope, to avoid finding member functions of the
7268 current class with same name. */
7269 push_nested_namespace (ns);
7270 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7271 tf_warning_or_error, NULL_TREE,
7272 /*integral_constant_expression_p=*/false);
7273 pop_nested_namespace (ns);
7274 arglist = tsubst (DECL_TI_ARGS (decl), args,
7275 tf_warning_or_error, NULL_TREE);
7276 template_id = lookup_template_function (fns, arglist);
7278 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7279 tmpl = determine_specialization (template_id, new_friend,
7281 /*need_member_template=*/0,
7282 TREE_VEC_LENGTH (args),
7284 return instantiate_template (tmpl, new_args, tf_error);
7287 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7289 /* The NEW_FRIEND will look like an instantiation, to the
7290 compiler, but is not an instantiation from the point of view of
7291 the language. For example, we might have had:
7293 template <class T> struct S {
7294 template <class U> friend void f(T, U);
7297 Then, in S<int>, template <class U> void f(int, U) is not an
7298 instantiation of anything. */
7299 if (new_friend == error_mark_node)
7300 return error_mark_node;
7302 DECL_USE_TEMPLATE (new_friend) = 0;
7303 if (TREE_CODE (decl) == TEMPLATE_DECL)
7305 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7306 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7307 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7310 /* The mangled name for the NEW_FRIEND is incorrect. The function
7311 is not a template instantiation and should not be mangled like
7312 one. Therefore, we forget the mangling here; we'll recompute it
7313 later if we need it. */
7314 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7316 SET_DECL_RTL (new_friend, NULL);
7317 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7320 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7323 tree new_friend_template_info;
7324 tree new_friend_result_template_info;
7326 int new_friend_is_defn;
7328 /* We must save some information from NEW_FRIEND before calling
7329 duplicate decls since that function will free NEW_FRIEND if
7331 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7332 new_friend_is_defn =
7333 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7334 (template_for_substitution (new_friend)))
7336 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7338 /* This declaration is a `primary' template. */
7339 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7341 new_friend_result_template_info
7342 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7345 new_friend_result_template_info = NULL_TREE;
7347 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7348 if (new_friend_is_defn)
7349 DECL_INITIAL (new_friend) = error_mark_node;
7351 /* Inside pushdecl_namespace_level, we will push into the
7352 current namespace. However, the friend function should go
7353 into the namespace of the template. */
7354 ns = decl_namespace_context (new_friend);
7355 push_nested_namespace (ns);
7356 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7357 pop_nested_namespace (ns);
7359 if (old_decl == error_mark_node)
7360 return error_mark_node;
7362 if (old_decl != new_friend)
7364 /* This new friend declaration matched an existing
7365 declaration. For example, given:
7367 template <class T> void f(T);
7368 template <class U> class C {
7369 template <class T> friend void f(T) {}
7372 the friend declaration actually provides the definition
7373 of `f', once C has been instantiated for some type. So,
7374 old_decl will be the out-of-class template declaration,
7375 while new_friend is the in-class definition.
7377 But, if `f' was called before this point, the
7378 instantiation of `f' will have DECL_TI_ARGS corresponding
7379 to `T' but not to `U', references to which might appear
7380 in the definition of `f'. Previously, the most general
7381 template for an instantiation of `f' was the out-of-class
7382 version; now it is the in-class version. Therefore, we
7383 run through all specialization of `f', adding to their
7384 DECL_TI_ARGS appropriately. In particular, they need a
7385 new set of outer arguments, corresponding to the
7386 arguments for this class instantiation.
7388 The same situation can arise with something like this:
7391 template <class T> class C {
7395 when `C<int>' is instantiated. Now, `f(int)' is defined
7398 if (!new_friend_is_defn)
7399 /* On the other hand, if the in-class declaration does
7400 *not* provide a definition, then we don't want to alter
7401 existing definitions. We can just leave everything
7406 tree new_template = TI_TEMPLATE (new_friend_template_info);
7407 tree new_args = TI_ARGS (new_friend_template_info);
7409 /* Overwrite whatever template info was there before, if
7410 any, with the new template information pertaining to
7412 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7414 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7416 /* We should have called reregister_specialization in
7418 gcc_assert (retrieve_specialization (new_template,
7422 /* Instantiate it if the global has already been used. */
7423 if (DECL_ODR_USED (old_decl))
7424 instantiate_decl (old_decl, /*defer_ok=*/true,
7425 /*expl_inst_class_mem_p=*/false);
7431 /* Indicate that the old function template is a partial
7433 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7434 = new_friend_result_template_info;
7436 gcc_assert (new_template
7437 == most_general_template (new_template));
7438 gcc_assert (new_template != old_decl);
7440 /* Reassign any specializations already in the hash table
7441 to the new more general template, and add the
7442 additional template args. */
7443 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7447 tree spec = TREE_VALUE (t);
7450 elt.tmpl = old_decl;
7451 elt.args = DECL_TI_ARGS (spec);
7452 elt.spec = NULL_TREE;
7454 htab_remove_elt (decl_specializations, &elt);
7457 = add_outermost_template_args (new_args,
7458 DECL_TI_ARGS (spec));
7460 register_specialization
7461 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7464 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7468 /* The information from NEW_FRIEND has been merged into OLD_DECL
7469 by duplicate_decls. */
7470 new_friend = old_decl;
7475 tree context = DECL_CONTEXT (new_friend);
7479 template <class T> class C {
7480 template <class U> friend void C1<U>::f (); // case 1
7481 friend void C2<T>::f (); // case 2
7483 we only need to make sure CONTEXT is a complete type for
7484 case 2. To distinguish between the two cases, we note that
7485 CONTEXT of case 1 remains dependent type after tsubst while
7486 this isn't true for case 2. */
7487 ++processing_template_decl;
7488 dependent_p = dependent_type_p (context);
7489 --processing_template_decl;
7492 && !complete_type_or_else (context, NULL_TREE))
7493 return error_mark_node;
7495 if (COMPLETE_TYPE_P (context))
7497 /* Check to see that the declaration is really present, and,
7498 possibly obtain an improved declaration. */
7499 tree fn = check_classfn (context,
7500 new_friend, NULL_TREE);
7510 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7511 template arguments, as for tsubst.
7513 Returns an appropriate tsubst'd friend type or error_mark_node on
7517 tsubst_friend_class (tree friend_tmpl, tree args)
7523 context = DECL_CONTEXT (friend_tmpl);
7527 if (TREE_CODE (context) == NAMESPACE_DECL)
7528 push_nested_namespace (context);
7530 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7533 /* Look for a class template declaration. We look for hidden names
7534 because two friend declarations of the same template are the
7535 same. For example, in:
7538 template <typename> friend class F;
7540 template <typename> struct B {
7541 template <typename> friend class F;
7544 both F templates are the same. */
7545 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7546 /*block_p=*/true, 0,
7547 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7549 /* But, if we don't find one, it might be because we're in a
7550 situation like this:
7558 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7559 for `S<int>', not the TEMPLATE_DECL. */
7560 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7562 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7563 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7566 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7568 /* The friend template has already been declared. Just
7569 check to see that the declarations match, and install any new
7570 default parameters. We must tsubst the default parameters,
7571 of course. We only need the innermost template parameters
7572 because that is all that redeclare_class_template will look
7574 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7575 > TMPL_ARGS_DEPTH (args))
7578 location_t saved_input_location;
7579 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7580 args, tf_warning_or_error);
7582 saved_input_location = input_location;
7583 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7584 redeclare_class_template (TREE_TYPE (tmpl), parms);
7585 input_location = saved_input_location;
7589 friend_type = TREE_TYPE (tmpl);
7593 /* The friend template has not already been declared. In this
7594 case, the instantiation of the template class will cause the
7595 injection of this template into the global scope. */
7596 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7597 if (tmpl == error_mark_node)
7598 return error_mark_node;
7600 /* The new TMPL is not an instantiation of anything, so we
7601 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7602 the new type because that is supposed to be the corresponding
7603 template decl, i.e., TMPL. */
7604 DECL_USE_TEMPLATE (tmpl) = 0;
7605 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7606 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7607 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7608 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7610 /* Inject this template into the global scope. */
7611 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7616 if (TREE_CODE (context) == NAMESPACE_DECL)
7617 pop_nested_namespace (context);
7619 pop_nested_class ();
7625 /* Returns zero if TYPE cannot be completed later due to circularity.
7626 Otherwise returns one. */
7629 can_complete_type_without_circularity (tree type)
7631 if (type == NULL_TREE || type == error_mark_node)
7633 else if (COMPLETE_TYPE_P (type))
7635 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7636 return can_complete_type_without_circularity (TREE_TYPE (type));
7637 else if (CLASS_TYPE_P (type)
7638 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7644 /* Apply any attributes which had to be deferred until instantiation
7645 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7646 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7649 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7650 tree args, tsubst_flags_t complain, tree in_decl)
7652 tree last_dep = NULL_TREE;
7656 for (t = attributes; t; t = TREE_CHAIN (t))
7657 if (ATTR_IS_DEPENDENT (t))
7660 attributes = copy_list (attributes);
7664 if (DECL_P (*decl_p))
7666 if (TREE_TYPE (*decl_p) == error_mark_node)
7668 p = &DECL_ATTRIBUTES (*decl_p);
7671 p = &TYPE_ATTRIBUTES (*decl_p);
7675 tree late_attrs = NULL_TREE;
7676 tree *q = &late_attrs;
7678 for (*p = attributes; *p; )
7681 if (ATTR_IS_DEPENDENT (t))
7683 *p = TREE_CHAIN (t);
7684 TREE_CHAIN (t) = NULL_TREE;
7685 /* If the first attribute argument is an identifier, don't
7686 pass it through tsubst. Attributes like mode, format,
7687 cleanup and several target specific attributes expect it
7690 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7691 && TREE_VALUE (TREE_VALUE (t))
7692 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7693 == IDENTIFIER_NODE))
7696 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7698 /*integral_constant_expression_p=*/false);
7699 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7701 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7706 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7707 /*integral_constant_expression_p=*/false);
7709 q = &TREE_CHAIN (t);
7712 p = &TREE_CHAIN (t);
7715 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7719 /* Perform (or defer) access check for typedefs that were referenced
7720 from within the template TMPL code.
7721 This is a subroutine of instantiate_template and instantiate_class_template.
7722 TMPL is the template to consider and TARGS is the list of arguments of
7726 perform_typedefs_access_check (tree tmpl, tree targs)
7728 location_t saved_location;
7730 qualified_typedef_usage_t *iter;
7733 || (!CLASS_TYPE_P (tmpl)
7734 && TREE_CODE (tmpl) != FUNCTION_DECL))
7737 saved_location = input_location;
7738 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
7739 get_types_needing_access_check (tmpl),
7742 tree type_decl = iter->typedef_decl;
7743 tree type_scope = iter->context;
7745 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7748 if (uses_template_parms (type_decl))
7749 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7750 if (uses_template_parms (type_scope))
7751 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7753 /* Make access check error messages point to the location
7754 of the use of the typedef. */
7755 input_location = iter->locus;
7756 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7757 type_decl, type_decl);
7759 input_location = saved_location;
7763 instantiate_class_template (tree type)
7765 tree templ, args, pattern, t, member;
7769 unsigned int saved_maximum_field_alignment;
7771 if (type == error_mark_node)
7772 return error_mark_node;
7774 if (COMPLETE_OR_OPEN_TYPE_P (type)
7775 || uses_template_parms (type))
7778 /* Figure out which template is being instantiated. */
7779 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7780 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7782 /* Determine what specialization of the original template to
7784 t = most_specialized_class (type, templ, tf_warning_or_error);
7785 if (t == error_mark_node)
7787 TYPE_BEING_DEFINED (type) = 1;
7788 return error_mark_node;
7792 /* This TYPE is actually an instantiation of a partial
7793 specialization. We replace the innermost set of ARGS with
7794 the arguments appropriate for substitution. For example,
7797 template <class T> struct S {};
7798 template <class T> struct S<T*> {};
7800 and supposing that we are instantiating S<int*>, ARGS will
7801 presently be {int*} -- but we need {int}. */
7802 pattern = TREE_TYPE (t);
7803 args = TREE_PURPOSE (t);
7807 pattern = TREE_TYPE (templ);
7808 args = CLASSTYPE_TI_ARGS (type);
7811 /* If the template we're instantiating is incomplete, then clearly
7812 there's nothing we can do. */
7813 if (!COMPLETE_TYPE_P (pattern))
7816 /* If we've recursively instantiated too many templates, stop. */
7817 if (! push_tinst_level (type))
7820 /* Now we're really doing the instantiation. Mark the type as in
7821 the process of being defined. */
7822 TYPE_BEING_DEFINED (type) = 1;
7824 /* We may be in the middle of deferred access check. Disable
7826 push_deferring_access_checks (dk_no_deferred);
7828 push_to_top_level ();
7829 /* Use #pragma pack from the template context. */
7830 saved_maximum_field_alignment = maximum_field_alignment;
7831 maximum_field_alignment = TYPE_PRECISION (pattern);
7833 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7835 /* Set the input location to the most specialized template definition.
7836 This is needed if tsubsting causes an error. */
7837 typedecl = TYPE_MAIN_DECL (pattern);
7838 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
7839 DECL_SOURCE_LOCATION (typedecl);
7841 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7842 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7843 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7844 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7845 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
7846 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
7847 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
7848 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
7849 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7850 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7851 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7852 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7853 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7854 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7855 if (ANON_AGGR_TYPE_P (pattern))
7856 SET_ANON_AGGR_TYPE_P (type);
7857 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7859 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7860 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7863 pbinfo = TYPE_BINFO (pattern);
7865 /* We should never instantiate a nested class before its enclosing
7866 class; we need to look up the nested class by name before we can
7867 instantiate it, and that lookup should instantiate the enclosing
7869 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7870 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
7872 base_list = NULL_TREE;
7873 if (BINFO_N_BASE_BINFOS (pbinfo))
7876 tree context = TYPE_CONTEXT (type);
7880 /* We must enter the scope containing the type, as that is where
7881 the accessibility of types named in dependent bases are
7883 pushed_scope = push_scope (context ? context : global_namespace);
7885 /* Substitute into each of the bases to determine the actual
7887 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7890 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7891 tree expanded_bases = NULL_TREE;
7894 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7897 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7898 args, tf_error, NULL_TREE);
7899 if (expanded_bases == error_mark_node)
7902 len = TREE_VEC_LENGTH (expanded_bases);
7905 for (idx = 0; idx < len; idx++)
7908 /* Extract the already-expanded base class. */
7909 base = TREE_VEC_ELT (expanded_bases, idx);
7911 /* Substitute to figure out the base class. */
7912 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7915 if (base == error_mark_node)
7918 base_list = tree_cons (access, base, base_list);
7919 if (BINFO_VIRTUAL_P (pbase_binfo))
7920 TREE_TYPE (base_list) = integer_type_node;
7924 /* The list is now in reverse order; correct that. */
7925 base_list = nreverse (base_list);
7928 pop_scope (pushed_scope);
7930 /* Now call xref_basetypes to set up all the base-class
7932 xref_basetypes (type, base_list);
7934 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7935 (int) ATTR_FLAG_TYPE_IN_PLACE,
7936 args, tf_error, NULL_TREE);
7938 /* Now that our base classes are set up, enter the scope of the
7939 class, so that name lookups into base classes, etc. will work
7940 correctly. This is precisely analogous to what we do in
7941 begin_class_definition when defining an ordinary non-template
7942 class, except we also need to push the enclosing classes. */
7943 push_nested_class (type);
7945 /* Now members are processed in the order of declaration. */
7946 for (member = CLASSTYPE_DECL_LIST (pattern);
7947 member; member = TREE_CHAIN (member))
7949 tree t = TREE_VALUE (member);
7951 if (TREE_PURPOSE (member))
7955 /* Build new CLASSTYPE_NESTED_UTDS. */
7958 bool class_template_p;
7960 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7961 && TYPE_LANG_SPECIFIC (t)
7962 && CLASSTYPE_IS_TEMPLATE (t));
7963 /* If the member is a class template, then -- even after
7964 substitution -- there may be dependent types in the
7965 template argument list for the class. We increment
7966 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7967 that function will assume that no types are dependent
7968 when outside of a template. */
7969 if (class_template_p)
7970 ++processing_template_decl;
7971 newtag = tsubst (t, args, tf_error, NULL_TREE);
7972 if (class_template_p)
7973 --processing_template_decl;
7974 if (newtag == error_mark_node)
7977 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7979 tree name = TYPE_IDENTIFIER (t);
7981 if (class_template_p)
7982 /* Unfortunately, lookup_template_class sets
7983 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7984 instantiation (i.e., for the type of a member
7985 template class nested within a template class.)
7986 This behavior is required for
7987 maybe_process_partial_specialization to work
7988 correctly, but is not accurate in this case;
7989 the TAG is not an instantiation of anything.
7990 (The corresponding TEMPLATE_DECL is an
7991 instantiation, but the TYPE is not.) */
7992 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7994 /* Now, we call pushtag to put this NEWTAG into the scope of
7995 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7996 pushtag calling push_template_decl. We don't have to do
7997 this for enums because it will already have been done in
8000 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8001 pushtag (name, newtag, /*tag_scope=*/ts_current);
8004 else if (TREE_CODE (t) == FUNCTION_DECL
8005 || DECL_FUNCTION_TEMPLATE_P (t))
8007 /* Build new TYPE_METHODS. */
8010 if (TREE_CODE (t) == TEMPLATE_DECL)
8011 ++processing_template_decl;
8012 r = tsubst (t, args, tf_error, NULL_TREE);
8013 if (TREE_CODE (t) == TEMPLATE_DECL)
8014 --processing_template_decl;
8015 set_current_access_from_decl (r);
8016 finish_member_declaration (r);
8020 /* Build new TYPE_FIELDS. */
8021 if (TREE_CODE (t) == STATIC_ASSERT)
8024 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8025 tf_warning_or_error, NULL_TREE,
8026 /*integral_constant_expression_p=*/true);
8027 finish_static_assert (condition,
8028 STATIC_ASSERT_MESSAGE (t),
8029 STATIC_ASSERT_SOURCE_LOCATION (t),
8032 else if (TREE_CODE (t) != CONST_DECL)
8036 /* The file and line for this declaration, to
8037 assist in error message reporting. Since we
8038 called push_tinst_level above, we don't need to
8040 input_location = DECL_SOURCE_LOCATION (t);
8042 if (TREE_CODE (t) == TEMPLATE_DECL)
8043 ++processing_template_decl;
8044 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8045 if (TREE_CODE (t) == TEMPLATE_DECL)
8046 --processing_template_decl;
8047 if (TREE_CODE (r) == VAR_DECL)
8051 [t]he initialization (and any associated
8052 side-effects) of a static data member does
8053 not occur unless the static data member is
8054 itself used in a way that requires the
8055 definition of the static data member to
8058 Therefore, we do not substitute into the
8059 initialized for the static data member here. */
8060 finish_static_data_member_decl
8063 /*init_const_expr_p=*/false,
8064 /*asmspec_tree=*/NULL_TREE,
8066 if (DECL_INITIALIZED_IN_CLASS_P (r))
8067 check_static_variable_definition (r, TREE_TYPE (r));
8069 else if (TREE_CODE (r) == FIELD_DECL)
8071 /* Determine whether R has a valid type and can be
8072 completed later. If R is invalid, then it is
8073 replaced by error_mark_node so that it will not be
8074 added to TYPE_FIELDS. */
8075 tree rtype = TREE_TYPE (r);
8076 if (can_complete_type_without_circularity (rtype))
8077 complete_type (rtype);
8079 if (!COMPLETE_TYPE_P (rtype))
8081 cxx_incomplete_type_error (r, rtype);
8082 r = error_mark_node;
8086 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8087 such a thing will already have been added to the field
8088 list by tsubst_enum in finish_member_declaration in the
8089 CLASSTYPE_NESTED_UTDS case above. */
8090 if (!(TREE_CODE (r) == TYPE_DECL
8091 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8092 && DECL_ARTIFICIAL (r)))
8094 set_current_access_from_decl (r);
8095 finish_member_declaration (r);
8102 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8104 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8106 tree friend_type = t;
8107 bool adjust_processing_template_decl = false;
8109 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8111 /* template <class T> friend class C; */
8112 friend_type = tsubst_friend_class (friend_type, args);
8113 adjust_processing_template_decl = true;
8115 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8117 /* template <class T> friend class C::D; */
8118 friend_type = tsubst (friend_type, args,
8119 tf_warning_or_error, NULL_TREE);
8120 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8121 friend_type = TREE_TYPE (friend_type);
8122 adjust_processing_template_decl = true;
8124 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
8126 /* This could be either
8130 when dependent_type_p is false or
8132 template <class U> friend class T::C;
8135 friend_type = tsubst (friend_type, args,
8136 tf_warning_or_error, NULL_TREE);
8137 /* Bump processing_template_decl for correct
8138 dependent_type_p calculation. */
8139 ++processing_template_decl;
8140 if (dependent_type_p (friend_type))
8141 adjust_processing_template_decl = true;
8142 --processing_template_decl;
8144 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8145 && hidden_name_p (TYPE_NAME (friend_type)))
8149 where C hasn't been declared yet. Let's lookup name
8150 from namespace scope directly, bypassing any name that
8151 come from dependent base class. */
8152 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8154 /* The call to xref_tag_from_type does injection for friend
8156 push_nested_namespace (ns);
8158 xref_tag_from_type (friend_type, NULL_TREE,
8159 /*tag_scope=*/ts_current);
8160 pop_nested_namespace (ns);
8162 else if (uses_template_parms (friend_type))
8163 /* friend class C<T>; */
8164 friend_type = tsubst (friend_type, args,
8165 tf_warning_or_error, NULL_TREE);
8170 where C is already declared or
8172 friend class C<int>;
8174 We don't have to do anything in these cases. */
8176 if (adjust_processing_template_decl)
8177 /* Trick make_friend_class into realizing that the friend
8178 we're adding is a template, not an ordinary class. It's
8179 important that we use make_friend_class since it will
8180 perform some error-checking and output cross-reference
8182 ++processing_template_decl;
8184 if (friend_type != error_mark_node)
8185 make_friend_class (type, friend_type, /*complain=*/false);
8187 if (adjust_processing_template_decl)
8188 --processing_template_decl;
8192 /* Build new DECL_FRIENDLIST. */
8195 /* The file and line for this declaration, to
8196 assist in error message reporting. Since we
8197 called push_tinst_level above, we don't need to
8199 input_location = DECL_SOURCE_LOCATION (t);
8201 if (TREE_CODE (t) == TEMPLATE_DECL)
8203 ++processing_template_decl;
8204 push_deferring_access_checks (dk_no_check);
8207 r = tsubst_friend_function (t, args);
8208 add_friend (type, r, /*complain=*/false);
8209 if (TREE_CODE (t) == TEMPLATE_DECL)
8211 pop_deferring_access_checks ();
8212 --processing_template_decl;
8218 /* Set the file and line number information to whatever is given for
8219 the class itself. This puts error messages involving generated
8220 implicit functions at a predictable point, and the same point
8221 that would be used for non-template classes. */
8222 input_location = DECL_SOURCE_LOCATION (typedecl);
8224 unreverse_member_declarations (type);
8225 finish_struct_1 (type);
8226 TYPE_BEING_DEFINED (type) = 0;
8228 /* Now that the class is complete, instantiate default arguments for
8229 any member functions. We don't do this earlier because the
8230 default arguments may reference members of the class. */
8231 if (!PRIMARY_TEMPLATE_P (templ))
8232 for (t = TYPE_METHODS (type); t; t = DECL_CHAIN (t))
8233 if (TREE_CODE (t) == FUNCTION_DECL
8234 /* Implicitly generated member functions will not have template
8235 information; they are not instantiations, but instead are
8236 created "fresh" for each instantiation. */
8237 && DECL_TEMPLATE_INFO (t))
8238 tsubst_default_arguments (t);
8240 /* Some typedefs referenced from within the template code need to be access
8241 checked at template instantiation time, i.e now. These types were
8242 added to the template at parsing time. Let's get those and perform
8243 the access checks then. */
8244 perform_typedefs_access_check (pattern, args);
8245 perform_deferred_access_checks ();
8246 pop_nested_class ();
8247 maximum_field_alignment = saved_maximum_field_alignment;
8248 pop_from_top_level ();
8249 pop_deferring_access_checks ();
8252 /* The vtable for a template class can be emitted in any translation
8253 unit in which the class is instantiated. When there is no key
8254 method, however, finish_struct_1 will already have added TYPE to
8255 the keyed_classes list. */
8256 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8257 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8263 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8269 else if (TYPE_P (t))
8270 r = tsubst (t, args, complain, in_decl);
8273 r = tsubst_expr (t, args, complain, in_decl,
8274 /*integral_constant_expression_p=*/true);
8275 r = fold_non_dependent_expr (r);
8280 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8281 NONTYPE_ARGUMENT_PACK. */
8284 make_fnparm_pack (tree spec_parm)
8286 /* Collect all of the extra "packed" parameters into an
8290 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8291 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8292 int i, len = list_length (spec_parm);
8294 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8295 parmvec = make_tree_vec (len);
8296 parmtypevec = make_tree_vec (len);
8297 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8299 TREE_VEC_ELT (parmvec, i) = spec_parm;
8300 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8303 /* Build the argument packs. */
8304 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8305 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8306 TREE_TYPE (argpack) = argtypepack;
8311 /* Substitute ARGS into T, which is an pack expansion
8312 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8313 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8314 (if only a partial substitution could be performed) or
8315 ERROR_MARK_NODE if there was an error. */
8317 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8321 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8325 htab_t saved_local_specializations = NULL;
8327 gcc_assert (PACK_EXPANSION_P (t));
8328 pattern = PACK_EXPANSION_PATTERN (t);
8330 /* Determine the argument packs that will instantiate the parameter
8331 packs used in the expansion expression. While we're at it,
8332 compute the number of arguments to be expanded and make sure it
8334 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8335 pack = TREE_CHAIN (pack))
8337 tree parm_pack = TREE_VALUE (pack);
8338 tree arg_pack = NULL_TREE;
8339 tree orig_arg = NULL_TREE;
8341 if (TREE_CODE (parm_pack) == PARM_DECL)
8343 if (!cp_unevaluated_operand)
8344 arg_pack = retrieve_local_specialization (parm_pack);
8347 /* We can't rely on local_specializations for a parameter
8348 name used later in a function declaration (such as in a
8349 late-specified return type). Even if it exists, it might
8350 have the wrong value for a recursive call. Just make a
8351 dummy decl, since it's only used for its type. */
8352 arg_pack = tsubst_decl (parm_pack, args, complain);
8353 arg_pack = make_fnparm_pack (arg_pack);
8358 int level, idx, levels;
8359 template_parm_level_and_index (parm_pack, &level, &idx);
8361 levels = TMPL_ARGS_DEPTH (args);
8362 if (level <= levels)
8363 arg_pack = TMPL_ARG (args, level, idx);
8366 orig_arg = arg_pack;
8367 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8368 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8370 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8371 /* This can only happen if we forget to expand an argument
8372 pack somewhere else. Just return an error, silently. */
8374 result = make_tree_vec (1);
8375 TREE_VEC_ELT (result, 0) = error_mark_node;
8380 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8381 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8383 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8384 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8385 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
8386 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
8387 /* The argument pack that the parameter maps to is just an
8388 expansion of the parameter itself, such as one would
8389 find in the implicit typedef of a class inside the
8390 class itself. Consider this parameter "unsubstituted",
8391 so that we will maintain the outer pack expansion. */
8392 arg_pack = NULL_TREE;
8398 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8400 /* It's all-or-nothing with incomplete argument packs. */
8401 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8402 return error_mark_node;
8404 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8409 else if (len != my_len)
8412 /* We got explicit args for some packs but not others;
8413 do nothing now and try again after deduction. */
8415 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8416 error ("mismatched argument pack lengths while expanding "
8420 error ("mismatched argument pack lengths while expanding "
8423 return error_mark_node;
8426 /* Keep track of the parameter packs and their corresponding
8428 packs = tree_cons (parm_pack, arg_pack, packs);
8429 TREE_TYPE (packs) = orig_arg;
8432 /* We can't substitute for this parameter pack. */
8433 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8435 unsubstituted_packs);
8438 /* We cannot expand this expansion expression, because we don't have
8439 all of the argument packs we need. Substitute into the pattern
8440 and return a PACK_EXPANSION_*. The caller will need to deal with
8442 if (unsubstituted_packs)
8445 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8446 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8447 /*integral_constant_expression_p=*/false);
8449 new_pat = tsubst (pattern, args, complain, in_decl);
8450 return make_pack_expansion (new_pat);
8453 /* We could not find any argument packs that work. */
8455 return error_mark_node;
8457 if (cp_unevaluated_operand)
8459 /* We're in a late-specified return type, so create our own local
8460 specializations table; the current table is either NULL or (in the
8461 case of recursive unification) might have bindings that we don't
8462 want to use or alter. */
8463 saved_local_specializations = local_specializations;
8464 local_specializations = htab_create (37,
8465 hash_local_specialization,
8466 eq_local_specializations,
8470 /* For each argument in each argument pack, substitute into the
8472 result = make_tree_vec (len + incomplete);
8473 for (i = 0; i < len + incomplete; ++i)
8475 /* For parameter pack, change the substitution of the parameter
8476 pack to the ith argument in its argument pack, then expand
8478 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8480 tree parm = TREE_PURPOSE (pack);
8482 if (TREE_CODE (parm) == PARM_DECL)
8484 /* Select the Ith argument from the pack. */
8485 tree arg = make_node (ARGUMENT_PACK_SELECT);
8486 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8487 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8489 register_local_specialization (arg, parm);
8495 template_parm_level_and_index (parm, &level, &idx);
8499 /* Select the Ith argument from the pack. */
8500 value = make_node (ARGUMENT_PACK_SELECT);
8501 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8502 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8505 /* Update the corresponding argument. */
8506 TMPL_ARG (args, level, idx) = value;
8510 /* Substitute into the PATTERN with the altered arguments. */
8511 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8512 TREE_VEC_ELT (result, i) =
8513 tsubst_expr (pattern, args, complain, in_decl,
8514 /*integral_constant_expression_p=*/false);
8516 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8519 /* When we have incomplete argument packs, the last "expanded"
8520 result is itself a pack expansion, which allows us
8521 to deduce more arguments. */
8522 TREE_VEC_ELT (result, i) =
8523 make_pack_expansion (TREE_VEC_ELT (result, i));
8525 if (TREE_VEC_ELT (result, i) == error_mark_node)
8527 result = error_mark_node;
8532 /* Update ARGS to restore the substitution from parameter packs to
8533 their argument packs. */
8534 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8536 tree parm = TREE_PURPOSE (pack);
8538 if (TREE_CODE (parm) == PARM_DECL)
8539 register_local_specialization (TREE_TYPE (pack), parm);
8543 template_parm_level_and_index (parm, &level, &idx);
8545 /* Update the corresponding argument. */
8546 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8547 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8550 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8554 if (saved_local_specializations)
8556 htab_delete (local_specializations);
8557 local_specializations = saved_local_specializations;
8563 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8564 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8565 parameter packs; all parms generated from a function parameter pack will
8566 have the same DECL_PARM_INDEX. */
8569 get_pattern_parm (tree parm, tree tmpl)
8571 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8574 if (DECL_ARTIFICIAL (parm))
8576 for (patparm = DECL_ARGUMENTS (pattern);
8577 patparm; patparm = DECL_CHAIN (patparm))
8578 if (DECL_ARTIFICIAL (patparm)
8579 && DECL_NAME (parm) == DECL_NAME (patparm))
8584 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8585 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8586 gcc_assert (DECL_PARM_INDEX (patparm)
8587 == DECL_PARM_INDEX (parm));
8593 /* Substitute ARGS into the vector or list of template arguments T. */
8596 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8599 int len = TREE_VEC_LENGTH (t);
8600 int need_new = 0, i, expanded_len_adjust = 0, out;
8601 tree *elts = XALLOCAVEC (tree, len);
8603 for (i = 0; i < len; i++)
8605 tree orig_arg = TREE_VEC_ELT (t, i);
8608 if (TREE_CODE (orig_arg) == TREE_VEC)
8609 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8610 else if (PACK_EXPANSION_P (orig_arg))
8612 /* Substitute into an expansion expression. */
8613 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8615 if (TREE_CODE (new_arg) == TREE_VEC)
8616 /* Add to the expanded length adjustment the number of
8617 expanded arguments. We subtract one from this
8618 measurement, because the argument pack expression
8619 itself is already counted as 1 in
8620 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8621 the argument pack is empty. */
8622 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8624 else if (ARGUMENT_PACK_P (orig_arg))
8626 /* Substitute into each of the arguments. */
8627 new_arg = TYPE_P (orig_arg)
8628 ? cxx_make_type (TREE_CODE (orig_arg))
8629 : make_node (TREE_CODE (orig_arg));
8631 SET_ARGUMENT_PACK_ARGS (
8633 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8634 args, complain, in_decl));
8636 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8637 new_arg = error_mark_node;
8639 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8640 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8642 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8644 if (TREE_TYPE (new_arg) == error_mark_node)
8645 new_arg = error_mark_node;
8649 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8651 if (new_arg == error_mark_node)
8652 return error_mark_node;
8655 if (new_arg != orig_arg)
8662 /* Make space for the expanded arguments coming from template
8664 t = make_tree_vec (len + expanded_len_adjust);
8665 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
8666 arguments for a member template.
8667 In that case each TREE_VEC in ORIG_T represents a level of template
8668 arguments, and ORIG_T won't carry any non defaulted argument count.
8669 It will rather be the nested TREE_VECs that will carry one.
8670 In other words, ORIG_T carries a non defaulted argument count only
8671 if it doesn't contain any nested TREE_VEC. */
8672 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
8674 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
8675 count += expanded_len_adjust;
8676 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
8678 for (i = 0, out = 0; i < len; i++)
8680 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8681 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8682 && TREE_CODE (elts[i]) == TREE_VEC)
8686 /* Now expand the template argument pack "in place". */
8687 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8688 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8692 TREE_VEC_ELT (t, out) = elts[i];
8700 /* Return the result of substituting ARGS into the template parameters
8701 given by PARMS. If there are m levels of ARGS and m + n levels of
8702 PARMS, then the result will contain n levels of PARMS. For
8703 example, if PARMS is `template <class T> template <class U>
8704 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8705 result will be `template <int*, double, class V>'. */
8708 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8713 /* When substituting into a template, we must set
8714 PROCESSING_TEMPLATE_DECL as the template parameters may be
8715 dependent if they are based on one-another, and the dependency
8716 predicates are short-circuit outside of templates. */
8717 ++processing_template_decl;
8719 for (new_parms = &r;
8720 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8721 new_parms = &(TREE_CHAIN (*new_parms)),
8722 parms = TREE_CHAIN (parms))
8725 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8728 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8734 if (parms == error_mark_node)
8737 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8739 if (tuple == error_mark_node)
8742 default_value = TREE_PURPOSE (tuple);
8743 parm_decl = TREE_VALUE (tuple);
8745 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8746 if (TREE_CODE (parm_decl) == PARM_DECL
8747 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8748 parm_decl = error_mark_node;
8749 default_value = tsubst_template_arg (default_value, args,
8750 complain, NULL_TREE);
8752 tuple = build_tree_list (default_value, parm_decl);
8753 TREE_VEC_ELT (new_vec, i) = tuple;
8757 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8758 - TMPL_ARGS_DEPTH (args)),
8759 new_vec, NULL_TREE);
8762 --processing_template_decl;
8767 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8768 type T. If T is not an aggregate or enumeration type, it is
8769 handled as if by tsubst. IN_DECL is as for tsubst. If
8770 ENTERING_SCOPE is nonzero, T is the context for a template which
8771 we are presently tsubst'ing. Return the substituted value. */
8774 tsubst_aggr_type (tree t,
8776 tsubst_flags_t complain,
8783 switch (TREE_CODE (t))
8786 if (TYPE_PTRMEMFUNC_P (t))
8787 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8789 /* Else fall through. */
8792 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8797 int saved_unevaluated_operand;
8798 int saved_inhibit_evaluation_warnings;
8800 /* In "sizeof(X<I>)" we need to evaluate "I". */
8801 saved_unevaluated_operand = cp_unevaluated_operand;
8802 cp_unevaluated_operand = 0;
8803 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8804 c_inhibit_evaluation_warnings = 0;
8806 /* First, determine the context for the type we are looking
8808 context = TYPE_CONTEXT (t);
8811 context = tsubst_aggr_type (context, args, complain,
8812 in_decl, /*entering_scope=*/1);
8813 /* If context is a nested class inside a class template,
8814 it may still need to be instantiated (c++/33959). */
8815 if (TYPE_P (context))
8816 context = complete_type (context);
8819 /* Then, figure out what arguments are appropriate for the
8820 type we are trying to find. For example, given:
8822 template <class T> struct S;
8823 template <class T, class U> void f(T, U) { S<U> su; }
8825 and supposing that we are instantiating f<int, double>,
8826 then our ARGS will be {int, double}, but, when looking up
8827 S we only want {double}. */
8828 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8830 if (argvec == error_mark_node)
8831 r = error_mark_node;
8834 r = lookup_template_class (t, argvec, in_decl, context,
8835 entering_scope, complain);
8836 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
8839 cp_unevaluated_operand = saved_unevaluated_operand;
8840 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8845 /* This is not a template type, so there's nothing to do. */
8849 return tsubst (t, args, complain, in_decl);
8853 /* Substitute into the default argument ARG (a default argument for
8854 FN), which has the indicated TYPE. */
8857 tsubst_default_argument (tree fn, tree type, tree arg)
8859 tree saved_class_ptr = NULL_TREE;
8860 tree saved_class_ref = NULL_TREE;
8862 /* This default argument came from a template. Instantiate the
8863 default argument here, not in tsubst. In the case of
8872 we must be careful to do name lookup in the scope of S<T>,
8873 rather than in the current class. */
8874 push_access_scope (fn);
8875 /* The "this" pointer is not valid in a default argument. */
8878 saved_class_ptr = current_class_ptr;
8879 cp_function_chain->x_current_class_ptr = NULL_TREE;
8880 saved_class_ref = current_class_ref;
8881 cp_function_chain->x_current_class_ref = NULL_TREE;
8884 push_deferring_access_checks(dk_no_deferred);
8885 /* The default argument expression may cause implicitly defined
8886 member functions to be synthesized, which will result in garbage
8887 collection. We must treat this situation as if we were within
8888 the body of function so as to avoid collecting live data on the
8891 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8892 tf_warning_or_error, NULL_TREE,
8893 /*integral_constant_expression_p=*/false);
8895 pop_deferring_access_checks();
8897 /* Restore the "this" pointer. */
8900 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8901 cp_function_chain->x_current_class_ref = saved_class_ref;
8904 /* Make sure the default argument is reasonable. */
8905 arg = check_default_argument (type, arg);
8907 pop_access_scope (fn);
8912 /* Substitute into all the default arguments for FN. */
8915 tsubst_default_arguments (tree fn)
8920 tmpl_args = DECL_TI_ARGS (fn);
8922 /* If this function is not yet instantiated, we certainly don't need
8923 its default arguments. */
8924 if (uses_template_parms (tmpl_args))
8927 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8929 arg = TREE_CHAIN (arg))
8930 if (TREE_PURPOSE (arg))
8931 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8933 TREE_PURPOSE (arg));
8936 /* Substitute the ARGS into the T, which is a _DECL. Return the
8937 result of the substitution. Issue error and warning messages under
8938 control of COMPLAIN. */
8941 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8943 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8944 location_t saved_loc;
8949 /* Set the filename and linenumber to improve error-reporting. */
8950 saved_loc = input_location;
8951 input_location = DECL_SOURCE_LOCATION (t);
8953 switch (TREE_CODE (t))
8957 /* We can get here when processing a member function template,
8958 member class template, or template template parameter. */
8959 tree decl = DECL_TEMPLATE_RESULT (t);
8964 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8966 /* Template template parameter is treated here. */
8967 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8968 if (new_type == error_mark_node)
8969 RETURN (error_mark_node);
8972 DECL_CHAIN (r) = NULL_TREE;
8973 TREE_TYPE (r) = new_type;
8974 DECL_TEMPLATE_RESULT (r)
8975 = build_decl (DECL_SOURCE_LOCATION (decl),
8976 TYPE_DECL, DECL_NAME (decl), new_type);
8977 DECL_TEMPLATE_PARMS (r)
8978 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8980 TYPE_NAME (new_type) = r;
8984 /* We might already have an instance of this template.
8985 The ARGS are for the surrounding class type, so the
8986 full args contain the tsubst'd args for the context,
8987 plus the innermost args from the template decl. */
8988 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8989 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8990 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8991 /* Because this is a template, the arguments will still be
8992 dependent, even after substitution. If
8993 PROCESSING_TEMPLATE_DECL is not set, the dependency
8994 predicates will short-circuit. */
8995 ++processing_template_decl;
8996 full_args = tsubst_template_args (tmpl_args, args,
8998 --processing_template_decl;
8999 if (full_args == error_mark_node)
9000 RETURN (error_mark_node);
9002 /* If this is a default template template argument,
9003 tsubst might not have changed anything. */
9004 if (full_args == tmpl_args)
9007 hash = hash_tmpl_and_args (t, full_args);
9008 spec = retrieve_specialization (t, full_args, hash);
9009 if (spec != NULL_TREE)
9015 /* Make a new template decl. It will be similar to the
9016 original, but will record the current template arguments.
9017 We also create a new function declaration, which is just
9018 like the old one, but points to this new template, rather
9019 than the old one. */
9021 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9022 DECL_CHAIN (r) = NULL_TREE;
9024 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9026 if (TREE_CODE (decl) == TYPE_DECL)
9029 ++processing_template_decl;
9030 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9031 --processing_template_decl;
9032 if (new_type == error_mark_node)
9033 RETURN (error_mark_node);
9035 TREE_TYPE (r) = new_type;
9036 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9037 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9038 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9039 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9044 ++processing_template_decl;
9045 new_decl = tsubst (decl, args, complain, in_decl);
9046 --processing_template_decl;
9047 if (new_decl == error_mark_node)
9048 RETURN (error_mark_node);
9050 DECL_TEMPLATE_RESULT (r) = new_decl;
9051 DECL_TI_TEMPLATE (new_decl) = r;
9052 TREE_TYPE (r) = TREE_TYPE (new_decl);
9053 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9054 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9057 SET_DECL_IMPLICIT_INSTANTIATION (r);
9058 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9059 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9061 /* The template parameters for this new template are all the
9062 template parameters for the old template, except the
9063 outermost level of parameters. */
9064 DECL_TEMPLATE_PARMS (r)
9065 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9068 if (PRIMARY_TEMPLATE_P (t))
9069 DECL_PRIMARY_TEMPLATE (r) = r;
9071 if (TREE_CODE (decl) != TYPE_DECL)
9072 /* Record this non-type partial instantiation. */
9073 register_specialization (r, t,
9074 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9082 tree argvec = NULL_TREE;
9090 /* Nobody should be tsubst'ing into non-template functions. */
9091 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9093 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9098 /* If T is not dependent, just return it. We have to
9099 increment PROCESSING_TEMPLATE_DECL because
9100 value_dependent_expression_p assumes that nothing is
9101 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9102 ++processing_template_decl;
9103 dependent_p = value_dependent_expression_p (t);
9104 --processing_template_decl;
9108 /* Calculate the most general template of which R is a
9109 specialization, and the complete set of arguments used to
9111 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9112 argvec = tsubst_template_args (DECL_TI_ARGS
9113 (DECL_TEMPLATE_RESULT
9114 (DECL_TI_TEMPLATE (t))),
9115 args, complain, in_decl);
9117 /* Check to see if we already have this specialization. */
9118 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9119 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9127 /* We can see more levels of arguments than parameters if
9128 there was a specialization of a member template, like
9131 template <class T> struct S { template <class U> void f(); }
9132 template <> template <class U> void S<int>::f(U);
9134 Here, we'll be substituting into the specialization,
9135 because that's where we can find the code we actually
9136 want to generate, but we'll have enough arguments for
9137 the most general template.
9139 We also deal with the peculiar case:
9141 template <class T> struct S {
9142 template <class U> friend void f();
9144 template <class U> void f() {}
9146 template void f<double>();
9148 Here, the ARGS for the instantiation of will be {int,
9149 double}. But, we only need as many ARGS as there are
9150 levels of template parameters in CODE_PATTERN. We are
9151 careful not to get fooled into reducing the ARGS in
9154 template <class T> struct S { template <class U> void f(U); }
9155 template <class T> template <> void S<T>::f(int) {}
9157 which we can spot because the pattern will be a
9158 specialization in this case. */
9159 args_depth = TMPL_ARGS_DEPTH (args);
9161 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9162 if (args_depth > parms_depth
9163 && !DECL_TEMPLATE_SPECIALIZATION (t))
9164 args = get_innermost_template_args (args, parms_depth);
9168 /* This special case arises when we have something like this:
9170 template <class T> struct S {
9171 friend void f<int>(int, double);
9174 Here, the DECL_TI_TEMPLATE for the friend declaration
9175 will be an IDENTIFIER_NODE. We are being called from
9176 tsubst_friend_function, and we want only to create a
9177 new decl (R) with appropriate types so that we can call
9178 determine_specialization. */
9179 gen_tmpl = NULL_TREE;
9182 if (DECL_CLASS_SCOPE_P (t))
9184 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9188 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9189 complain, t, /*entering_scope=*/1);
9194 ctx = DECL_CONTEXT (t);
9196 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9197 if (type == error_mark_node)
9198 RETURN (error_mark_node);
9200 /* We do NOT check for matching decls pushed separately at this
9201 point, as they may not represent instantiations of this
9202 template, and in any case are considered separate under the
9205 DECL_USE_TEMPLATE (r) = 0;
9206 TREE_TYPE (r) = type;
9207 /* Clear out the mangled name and RTL for the instantiation. */
9208 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9209 SET_DECL_RTL (r, NULL);
9210 /* Leave DECL_INITIAL set on deleted instantiations. */
9211 if (!DECL_DELETED_FN (r))
9212 DECL_INITIAL (r) = NULL_TREE;
9213 DECL_CONTEXT (r) = ctx;
9215 if (member && DECL_CONV_FN_P (r))
9216 /* Type-conversion operator. Reconstruct the name, in
9217 case it's the name of one of the template's parameters. */
9218 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9220 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9222 DECL_RESULT (r) = NULL_TREE;
9224 TREE_STATIC (r) = 0;
9225 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9226 DECL_EXTERNAL (r) = 1;
9227 /* If this is an instantiation of a function with internal
9228 linkage, we already know what object file linkage will be
9229 assigned to the instantiation. */
9230 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9231 DECL_DEFER_OUTPUT (r) = 0;
9232 DECL_CHAIN (r) = NULL_TREE;
9233 DECL_PENDING_INLINE_INFO (r) = 0;
9234 DECL_PENDING_INLINE_P (r) = 0;
9235 DECL_SAVED_TREE (r) = NULL_TREE;
9236 DECL_STRUCT_FUNCTION (r) = NULL;
9238 /* We'll re-clone as appropriate in instantiate_template. */
9239 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9241 /* If we aren't complaining now, return on error before we register
9242 the specialization so that we'll complain eventually. */
9243 if ((complain & tf_error) == 0
9244 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9245 && !grok_op_properties (r, /*complain=*/false))
9246 RETURN (error_mark_node);
9248 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9249 this in the special friend case mentioned above where
9250 GEN_TMPL is NULL. */
9253 DECL_TEMPLATE_INFO (r)
9254 = build_template_info (gen_tmpl, argvec);
9255 SET_DECL_IMPLICIT_INSTANTIATION (r);
9256 register_specialization (r, gen_tmpl, argvec, false, hash);
9258 /* We're not supposed to instantiate default arguments
9259 until they are called, for a template. But, for a
9262 template <class T> void f ()
9263 { extern void g(int i = T()); }
9265 we should do the substitution when the template is
9266 instantiated. We handle the member function case in
9267 instantiate_class_template since the default arguments
9268 might refer to other members of the class. */
9270 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9271 && !uses_template_parms (argvec))
9272 tsubst_default_arguments (r);
9275 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9277 /* Copy the list of befriending classes. */
9278 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9280 friends = &TREE_CHAIN (*friends))
9282 *friends = copy_node (*friends);
9283 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9288 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9290 maybe_retrofit_in_chrg (r);
9291 if (DECL_CONSTRUCTOR_P (r))
9292 grok_ctor_properties (ctx, r);
9293 /* If this is an instantiation of a member template, clone it.
9294 If it isn't, that'll be handled by
9295 clone_constructors_and_destructors. */
9296 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9297 clone_function_decl (r, /*update_method_vec_p=*/0);
9299 else if ((complain & tf_error) != 0
9300 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9301 && !grok_op_properties (r, /*complain=*/true))
9302 RETURN (error_mark_node);
9304 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9305 SET_DECL_FRIEND_CONTEXT (r,
9306 tsubst (DECL_FRIEND_CONTEXT (t),
9307 args, complain, in_decl));
9309 /* Possibly limit visibility based on template args. */
9310 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9311 if (DECL_VISIBILITY_SPECIFIED (t))
9313 DECL_VISIBILITY_SPECIFIED (r) = 0;
9315 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9317 determine_visibility (r);
9318 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9319 && !processing_template_decl)
9320 defaulted_late_check (r);
9322 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9323 args, complain, in_decl);
9329 tree type = NULL_TREE;
9331 tree expanded_types = NULL_TREE;
9332 tree prev_r = NULL_TREE;
9333 tree first_r = NULL_TREE;
9335 if (FUNCTION_PARAMETER_PACK_P (t))
9337 /* If there is a local specialization that isn't a
9338 parameter pack, it means that we're doing a "simple"
9339 substitution from inside tsubst_pack_expansion. Just
9340 return the local specialization (which will be a single
9342 tree spec = retrieve_local_specialization (t);
9344 && TREE_CODE (spec) == PARM_DECL
9345 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9348 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9349 the parameters in this function parameter pack. */
9350 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9352 if (TREE_CODE (expanded_types) == TREE_VEC)
9354 len = TREE_VEC_LENGTH (expanded_types);
9356 /* Zero-length parameter packs are boring. Just substitute
9359 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9364 /* All we did was update the type. Make a note of that. */
9365 type = expanded_types;
9366 expanded_types = NULL_TREE;
9370 /* Loop through all of the parameter's we'll build. When T is
9371 a function parameter pack, LEN is the number of expanded
9372 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9374 for (i = 0; i < len; ++i)
9378 if (DECL_TEMPLATE_PARM_P (t))
9379 SET_DECL_TEMPLATE_PARM_P (r);
9381 /* An argument of a function parameter pack is not a parameter
9383 FUNCTION_PARAMETER_PACK_P (r) = false;
9386 /* We're on the Ith parameter of the function parameter
9389 /* Get the Ith type. */
9390 type = TREE_VEC_ELT (expanded_types, i);
9393 /* Rename the parameter to include the index. */
9395 make_ith_pack_parameter_name (DECL_NAME (r), i);
9398 /* We're dealing with a normal parameter. */
9399 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9401 type = type_decays_to (type);
9402 TREE_TYPE (r) = type;
9403 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9405 if (DECL_INITIAL (r))
9407 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9408 DECL_INITIAL (r) = TREE_TYPE (r);
9410 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9414 DECL_CONTEXT (r) = NULL_TREE;
9416 if (!DECL_TEMPLATE_PARM_P (r))
9417 DECL_ARG_TYPE (r) = type_passed_as (type);
9419 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9420 args, complain, in_decl);
9422 /* Keep track of the first new parameter we
9423 generate. That's what will be returned to the
9428 /* Build a proper chain of parameters when substituting
9429 into a function parameter pack. */
9431 DECL_CHAIN (prev_r) = r;
9435 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9436 complain, DECL_CHAIN (t));
9438 /* FIRST_R contains the start of the chain we've built. */
9448 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9449 if (type == error_mark_node)
9450 RETURN (error_mark_node);
9451 TREE_TYPE (r) = type;
9452 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9454 /* DECL_INITIAL gives the number of bits in a bit-field. */
9456 = tsubst_expr (DECL_INITIAL (t), args,
9458 /*integral_constant_expression_p=*/true);
9459 /* We don't have to set DECL_CONTEXT here; it is set by
9460 finish_member_declaration. */
9461 DECL_CHAIN (r) = NULL_TREE;
9462 if (VOID_TYPE_P (type))
9463 error ("instantiation of %q+D as type %qT", r, type);
9465 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9466 args, complain, in_decl);
9471 /* We reach here only for member using decls. */
9472 if (DECL_DEPENDENT_P (t))
9474 r = do_class_using_decl
9475 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9476 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9478 r = error_mark_node;
9481 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9482 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9488 DECL_CHAIN (r) = NULL_TREE;
9495 tree argvec = NULL_TREE;
9496 tree gen_tmpl = NULL_TREE;
9498 tree tmpl = NULL_TREE;
9500 tree type = NULL_TREE;
9503 if (TREE_CODE (t) == TYPE_DECL
9504 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9506 /* If this is the canonical decl, we don't have to
9507 mess with instantiations, and often we can't (for
9508 typename, template type parms and such). Note that
9509 TYPE_NAME is not correct for the above test if
9510 we've copied the type for a typedef. */
9511 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9512 if (type == error_mark_node)
9513 RETURN (error_mark_node);
9514 r = TYPE_NAME (type);
9518 /* Check to see if we already have the specialization we
9521 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9523 /* T is a static data member or namespace-scope entity.
9524 We have to substitute into namespace-scope variables
9525 (even though such entities are never templates) because
9528 template <class T> void f() { extern T t; }
9530 where the entity referenced is not known until
9531 instantiation time. */
9533 ctx = DECL_CONTEXT (t);
9534 if (DECL_CLASS_SCOPE_P (t))
9536 ctx = tsubst_aggr_type (ctx, args,
9538 in_decl, /*entering_scope=*/1);
9539 /* If CTX is unchanged, then T is in fact the
9540 specialization we want. That situation occurs when
9541 referencing a static data member within in its own
9542 class. We can use pointer equality, rather than
9543 same_type_p, because DECL_CONTEXT is always
9545 if (ctx == DECL_CONTEXT (t))
9551 tmpl = DECL_TI_TEMPLATE (t);
9552 gen_tmpl = most_general_template (tmpl);
9553 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9554 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9555 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9560 /* A local variable. */
9562 /* Subsequent calls to pushdecl will fill this in. */
9564 spec = retrieve_local_specialization (t);
9566 /* If we already have the specialization we need, there is
9567 nothing more to do. */
9574 /* Create a new node for the specialization we need. */
9576 if (type == NULL_TREE)
9578 if (is_typedef_decl (t))
9579 type = DECL_ORIGINAL_TYPE (t);
9581 type = TREE_TYPE (t);
9582 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
9583 type = strip_array_domain (type);
9584 type = tsubst (type, args, complain, in_decl);
9586 if (TREE_CODE (r) == VAR_DECL)
9588 /* Even if the original location is out of scope, the
9589 newly substituted one is not. */
9590 DECL_DEAD_FOR_LOCAL (r) = 0;
9591 DECL_INITIALIZED_P (r) = 0;
9592 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9593 if (type == error_mark_node)
9594 RETURN (error_mark_node);
9595 if (TREE_CODE (type) == FUNCTION_TYPE)
9597 /* It may seem that this case cannot occur, since:
9602 declares a function, not a variable. However:
9605 template <typename T> void g() { T t; }
9606 template void g<f>();
9608 is an attempt to declare a variable with function
9610 error ("variable %qD has function type",
9611 /* R is not yet sufficiently initialized, so we
9612 just use its name. */
9614 RETURN (error_mark_node);
9616 type = complete_type (type);
9617 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9618 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9619 type = check_var_type (DECL_NAME (r), type);
9621 if (DECL_HAS_VALUE_EXPR_P (t))
9623 tree ve = DECL_VALUE_EXPR (t);
9624 ve = tsubst_expr (ve, args, complain, in_decl,
9625 /*constant_expression_p=*/false);
9626 SET_DECL_VALUE_EXPR (r, ve);
9629 else if (DECL_SELF_REFERENCE_P (t))
9630 SET_DECL_SELF_REFERENCE_P (r);
9631 TREE_TYPE (r) = type;
9632 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9633 DECL_CONTEXT (r) = ctx;
9634 /* Clear out the mangled name and RTL for the instantiation. */
9635 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9636 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9637 SET_DECL_RTL (r, NULL);
9638 /* The initializer must not be expanded until it is required;
9640 DECL_INITIAL (r) = NULL_TREE;
9641 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9642 SET_DECL_RTL (r, NULL);
9643 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9644 if (TREE_CODE (r) == VAR_DECL)
9646 /* Possibly limit visibility based on template args. */
9647 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9648 if (DECL_VISIBILITY_SPECIFIED (t))
9650 DECL_VISIBILITY_SPECIFIED (r) = 0;
9652 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9654 determine_visibility (r);
9659 /* A static data member declaration is always marked
9660 external when it is declared in-class, even if an
9661 initializer is present. We mimic the non-template
9663 DECL_EXTERNAL (r) = 1;
9665 register_specialization (r, gen_tmpl, argvec, false, hash);
9666 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
9667 SET_DECL_IMPLICIT_INSTANTIATION (r);
9669 else if (cp_unevaluated_operand)
9671 /* We're substituting this var in a decltype outside of its
9672 scope, such as for a lambda return type. Don't add it to
9673 local_specializations, do perform auto deduction. */
9674 tree auto_node = type_uses_auto (type);
9676 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9677 /*constant_expression_p=*/false);
9679 if (auto_node && init && describable_type (init))
9681 type = do_auto_deduction (type, init, auto_node);
9682 TREE_TYPE (r) = type;
9686 register_local_specialization (r, t);
9688 DECL_CHAIN (r) = NULL_TREE;
9690 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9692 args, complain, in_decl);
9694 /* Preserve a typedef that names a type. */
9695 if (is_typedef_decl (r))
9697 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
9698 set_underlying_type (r);
9711 /* Restore the file and line information. */
9712 input_location = saved_loc;
9717 /* Substitute into the ARG_TYPES of a function type. */
9720 tsubst_arg_types (tree arg_types,
9722 tsubst_flags_t complain,
9725 tree remaining_arg_types;
9726 tree type = NULL_TREE;
9728 tree expanded_args = NULL_TREE;
9731 if (!arg_types || arg_types == void_list_node)
9734 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9735 args, complain, in_decl);
9736 if (remaining_arg_types == error_mark_node)
9737 return error_mark_node;
9739 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9741 /* For a pack expansion, perform substitution on the
9742 entire expression. Later on, we'll handle the arguments
9744 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9745 args, complain, in_decl);
9747 if (TREE_CODE (expanded_args) == TREE_VEC)
9748 /* So that we'll spin through the parameters, one by one. */
9749 i = TREE_VEC_LENGTH (expanded_args);
9752 /* We only partially substituted into the parameter
9753 pack. Our type is TYPE_PACK_EXPANSION. */
9754 type = expanded_args;
9755 expanded_args = NULL_TREE;
9763 type = TREE_VEC_ELT (expanded_args, i);
9765 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9767 if (type == error_mark_node)
9768 return error_mark_node;
9769 if (VOID_TYPE_P (type))
9771 if (complain & tf_error)
9773 error ("invalid parameter type %qT", type);
9775 error ("in declaration %q+D", in_decl);
9777 return error_mark_node;
9780 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9781 top-level qualifiers as required. */
9782 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9784 /* We do not substitute into default arguments here. The standard
9785 mandates that they be instantiated only when needed, which is
9786 done in build_over_call. */
9787 default_arg = TREE_PURPOSE (arg_types);
9789 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9791 /* We've instantiated a template before its default arguments
9792 have been parsed. This can happen for a nested template
9793 class, and is not an error unless we require the default
9794 argument in a call of this function. */
9795 remaining_arg_types =
9796 tree_cons (default_arg, type, remaining_arg_types);
9797 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9798 remaining_arg_types);
9801 remaining_arg_types =
9802 hash_tree_cons (default_arg, type, remaining_arg_types);
9805 return remaining_arg_types;
9808 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9809 *not* handle the exception-specification for FNTYPE, because the
9810 initial substitution of explicitly provided template parameters
9811 during argument deduction forbids substitution into the
9812 exception-specification:
9816 All references in the function type of the function template to the
9817 corresponding template parameters are replaced by the specified tem-
9818 plate argument values. If a substitution in a template parameter or
9819 in the function type of the function template results in an invalid
9820 type, type deduction fails. [Note: The equivalent substitution in
9821 exception specifications is done only when the function is instanti-
9822 ated, at which point a program is ill-formed if the substitution
9823 results in an invalid type.] */
9826 tsubst_function_type (tree t,
9828 tsubst_flags_t complain,
9835 /* The TYPE_CONTEXT is not used for function/method types. */
9836 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9838 /* Substitute the return type. */
9839 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9840 if (return_type == error_mark_node)
9841 return error_mark_node;
9842 /* The standard does not presently indicate that creation of a
9843 function type with an invalid return type is a deduction failure.
9844 However, that is clearly analogous to creating an array of "void"
9845 or a reference to a reference. This is core issue #486. */
9846 if (TREE_CODE (return_type) == ARRAY_TYPE
9847 || TREE_CODE (return_type) == FUNCTION_TYPE)
9849 if (complain & tf_error)
9851 if (TREE_CODE (return_type) == ARRAY_TYPE)
9852 error ("function returning an array");
9854 error ("function returning a function");
9856 return error_mark_node;
9859 /* Substitute the argument types. */
9860 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9862 if (arg_types == error_mark_node)
9863 return error_mark_node;
9865 /* Construct a new type node and return it. */
9866 if (TREE_CODE (t) == FUNCTION_TYPE)
9868 fntype = build_function_type (return_type, arg_types);
9869 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
9873 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9874 if (! MAYBE_CLASS_TYPE_P (r))
9878 Type deduction may fail for any of the following
9881 -- Attempting to create "pointer to member of T" when T
9882 is not a class type. */
9883 if (complain & tf_error)
9884 error ("creating pointer to member function of non-class type %qT",
9886 return error_mark_node;
9889 fntype = build_method_type_directly (r, return_type,
9890 TREE_CHAIN (arg_types));
9892 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9897 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9898 ARGS into that specification, and return the substituted
9899 specification. If there is no specification, return NULL_TREE. */
9902 tsubst_exception_specification (tree fntype,
9904 tsubst_flags_t complain,
9910 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9911 new_specs = NULL_TREE;
9912 if (specs && TREE_PURPOSE (specs))
9914 /* A noexcept-specifier. */
9915 new_specs = tsubst_copy_and_build
9916 (TREE_PURPOSE (specs), args, complain, in_decl, /*function_p=*/false,
9917 /*integral_constant_expression_p=*/true);
9918 new_specs = build_noexcept_spec (new_specs, complain);
9922 if (! TREE_VALUE (specs))
9929 tree expanded_specs = NULL_TREE;
9931 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9933 /* Expand the pack expansion type. */
9934 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9938 if (expanded_specs == error_mark_node)
9939 return error_mark_node;
9940 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9941 len = TREE_VEC_LENGTH (expanded_specs);
9944 /* We're substituting into a member template, so
9945 we got a TYPE_PACK_EXPANSION back. Add that
9946 expansion and move on. */
9947 gcc_assert (TREE_CODE (expanded_specs)
9948 == TYPE_PACK_EXPANSION);
9949 new_specs = add_exception_specifier (new_specs,
9952 specs = TREE_CHAIN (specs);
9957 for (i = 0; i < len; ++i)
9960 spec = TREE_VEC_ELT (expanded_specs, i);
9962 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9963 if (spec == error_mark_node)
9965 new_specs = add_exception_specifier (new_specs, spec,
9969 specs = TREE_CHAIN (specs);
9975 /* Take the tree structure T and replace template parameters used
9976 therein with the argument vector ARGS. IN_DECL is an associated
9977 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9978 Issue error and warning messages under control of COMPLAIN. Note
9979 that we must be relatively non-tolerant of extensions here, in
9980 order to preserve conformance; if we allow substitutions that
9981 should not be allowed, we may allow argument deductions that should
9982 not succeed, and therefore report ambiguous overload situations
9983 where there are none. In theory, we could allow the substitution,
9984 but indicate that it should have failed, and allow our caller to
9985 make sure that the right thing happens, but we don't try to do this
9988 This function is used for dealing with types, decls and the like;
9989 for expressions, use tsubst_expr or tsubst_copy. */
9992 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9994 enum tree_code code;
9997 if (t == NULL_TREE || t == error_mark_node
9998 || t == integer_type_node
9999 || t == void_type_node
10000 || t == char_type_node
10001 || t == unknown_type_node
10002 || TREE_CODE (t) == NAMESPACE_DECL)
10006 return tsubst_decl (t, args, complain);
10008 if (args == NULL_TREE)
10011 code = TREE_CODE (t);
10013 if (code == IDENTIFIER_NODE)
10014 type = IDENTIFIER_TYPE_VALUE (t);
10016 type = TREE_TYPE (t);
10018 gcc_assert (type != unknown_type_node);
10020 /* Reuse typedefs. We need to do this to handle dependent attributes,
10021 such as attribute aligned. */
10024 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
10026 tree decl = TYPE_NAME (t);
10028 if (DECL_CLASS_SCOPE_P (decl)
10029 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10030 && uses_template_parms (DECL_CONTEXT (decl)))
10032 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10033 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10034 r = retrieve_specialization (tmpl, gen_args, 0);
10036 else if (DECL_FUNCTION_SCOPE_P (decl)
10037 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10038 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10039 r = retrieve_local_specialization (decl);
10041 /* The typedef is from a non-template context. */
10047 r = cp_build_qualified_type_real
10048 (r, cp_type_quals (t) | cp_type_quals (r),
10049 complain | tf_ignore_bad_quals);
10052 /* Else we must be instantiating the typedef, so fall through. */
10056 && code != TYPENAME_TYPE
10057 && code != TEMPLATE_TYPE_PARM
10058 && code != IDENTIFIER_NODE
10059 && code != FUNCTION_TYPE
10060 && code != METHOD_TYPE)
10061 type = tsubst (type, args, complain, in_decl);
10062 if (type == error_mark_node)
10063 return error_mark_node;
10069 case ENUMERAL_TYPE:
10070 return tsubst_aggr_type (t, args, complain, in_decl,
10071 /*entering_scope=*/0);
10074 case IDENTIFIER_NODE:
10086 if (t == integer_type_node)
10089 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10090 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10094 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10096 max = tsubst_expr (omax, args, complain, in_decl,
10097 /*integral_constant_expression_p=*/false);
10099 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10101 if (TREE_CODE (max) == NOP_EXPR
10102 && TREE_SIDE_EFFECTS (omax)
10103 && !TREE_TYPE (max))
10104 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10106 max = fold_decl_constant_value (max);
10108 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10109 with TREE_SIDE_EFFECTS that indicates this is not an integral
10110 constant expression. */
10111 if (processing_template_decl
10112 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10114 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10115 TREE_SIDE_EFFECTS (max) = 1;
10118 if (TREE_CODE (max) != INTEGER_CST
10119 && !at_function_scope_p ()
10120 && !TREE_SIDE_EFFECTS (max)
10121 && !value_dependent_expression_p (max))
10123 if (complain & tf_error)
10124 error ("array bound is not an integer constant");
10125 return error_mark_node;
10130 Type deduction may fail for any of the following
10133 Attempting to create an array with a size that is
10134 zero or negative. */
10135 if (integer_zerop (max) && !(complain & tf_error))
10136 /* We must fail if performing argument deduction (as
10137 indicated by the state of complain), so that
10138 another substitution can be found. */
10139 return error_mark_node;
10140 else if (TREE_CODE (max) == INTEGER_CST
10141 && INT_CST_LT (max, integer_zero_node))
10143 if (complain & tf_error)
10144 error ("creating array with negative size (%qE)", max);
10146 return error_mark_node;
10149 return compute_array_index_type (NULL_TREE, max);
10152 case TEMPLATE_TYPE_PARM:
10153 case TEMPLATE_TEMPLATE_PARM:
10154 case BOUND_TEMPLATE_TEMPLATE_PARM:
10155 case TEMPLATE_PARM_INDEX:
10160 tree arg = NULL_TREE;
10164 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10165 template_parm_level_and_index (t, &level, &idx);
10167 levels = TMPL_ARGS_DEPTH (args);
10168 if (level <= levels)
10170 arg = TMPL_ARG (args, level, idx);
10172 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10173 /* See through ARGUMENT_PACK_SELECT arguments. */
10174 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10177 if (arg == error_mark_node)
10178 return error_mark_node;
10179 else if (arg != NULL_TREE)
10181 if (ARGUMENT_PACK_P (arg))
10182 /* If ARG is an argument pack, we don't actually want to
10183 perform a substitution here, because substitutions
10184 for argument packs are only done
10185 element-by-element. We can get to this point when
10186 substituting the type of a non-type template
10187 parameter pack, when that type actually contains
10188 template parameter packs from an outer template, e.g.,
10190 template<typename... Types> struct A {
10191 template<Types... Values> struct B { };
10195 if (code == TEMPLATE_TYPE_PARM)
10198 gcc_assert (TYPE_P (arg));
10200 quals = cp_type_quals (arg) | cp_type_quals (t);
10202 return cp_build_qualified_type_real
10203 (arg, quals, complain | tf_ignore_bad_quals);
10205 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10207 /* We are processing a type constructed from a
10208 template template parameter. */
10209 tree argvec = tsubst (TYPE_TI_ARGS (t),
10210 args, complain, in_decl);
10211 if (argvec == error_mark_node)
10212 return error_mark_node;
10214 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10215 are resolving nested-types in the signature of a
10216 member function templates. Otherwise ARG is a
10217 TEMPLATE_DECL and is the real template to be
10219 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10220 arg = TYPE_NAME (arg);
10222 r = lookup_template_class (arg,
10224 DECL_CONTEXT (arg),
10225 /*entering_scope=*/0,
10227 return cp_build_qualified_type_real
10228 (r, cp_type_quals (t), complain);
10231 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10232 return unshare_expr (arg);
10236 /* This can happen during the attempted tsubst'ing in
10237 unify. This means that we don't yet have any information
10238 about the template parameter in question. */
10241 /* If we get here, we must have been looking at a parm for a
10242 more deeply nested template. Make a new version of this
10243 template parameter, but with a lower level. */
10246 case TEMPLATE_TYPE_PARM:
10247 case TEMPLATE_TEMPLATE_PARM:
10248 case BOUND_TEMPLATE_TEMPLATE_PARM:
10249 if (cp_type_quals (t))
10251 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10252 r = cp_build_qualified_type_real
10253 (r, cp_type_quals (t),
10254 complain | (code == TEMPLATE_TYPE_PARM
10255 ? tf_ignore_bad_quals : 0));
10260 TEMPLATE_TYPE_PARM_INDEX (r)
10261 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10262 r, levels, args, complain);
10263 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10264 TYPE_MAIN_VARIANT (r) = r;
10265 TYPE_POINTER_TO (r) = NULL_TREE;
10266 TYPE_REFERENCE_TO (r) = NULL_TREE;
10268 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10269 /* We have reduced the level of the template
10270 template parameter, but not the levels of its
10271 template parameters, so canonical_type_parameter
10272 will not be able to find the canonical template
10273 template parameter for this level. Thus, we
10274 require structural equality checking to compare
10275 TEMPLATE_TEMPLATE_PARMs. */
10276 SET_TYPE_STRUCTURAL_EQUALITY (r);
10277 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10278 SET_TYPE_STRUCTURAL_EQUALITY (r);
10280 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10282 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10284 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10285 complain, in_decl);
10286 if (argvec == error_mark_node)
10287 return error_mark_node;
10289 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10290 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10295 case TEMPLATE_PARM_INDEX:
10296 r = reduce_template_parm_level (t, type, levels, args, complain);
10300 gcc_unreachable ();
10308 tree purpose, value, chain;
10310 if (t == void_list_node)
10313 purpose = TREE_PURPOSE (t);
10316 purpose = tsubst (purpose, args, complain, in_decl);
10317 if (purpose == error_mark_node)
10318 return error_mark_node;
10320 value = TREE_VALUE (t);
10323 value = tsubst (value, args, complain, in_decl);
10324 if (value == error_mark_node)
10325 return error_mark_node;
10327 chain = TREE_CHAIN (t);
10328 if (chain && chain != void_type_node)
10330 chain = tsubst (chain, args, complain, in_decl);
10331 if (chain == error_mark_node)
10332 return error_mark_node;
10334 if (purpose == TREE_PURPOSE (t)
10335 && value == TREE_VALUE (t)
10336 && chain == TREE_CHAIN (t))
10338 return hash_tree_cons (purpose, value, chain);
10342 /* We should never be tsubsting a binfo. */
10343 gcc_unreachable ();
10346 /* A vector of template arguments. */
10347 gcc_assert (!type);
10348 return tsubst_template_args (t, args, complain, in_decl);
10351 case REFERENCE_TYPE:
10353 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10358 Type deduction may fail for any of the following
10361 -- Attempting to create a pointer to reference type.
10362 -- Attempting to create a reference to a reference type or
10363 a reference to void.
10365 Core issue 106 says that creating a reference to a reference
10366 during instantiation is no longer a cause for failure. We
10367 only enforce this check in strict C++98 mode. */
10368 if ((TREE_CODE (type) == REFERENCE_TYPE
10369 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10370 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10372 static location_t last_loc;
10374 /* We keep track of the last time we issued this error
10375 message to avoid spewing a ton of messages during a
10376 single bad template instantiation. */
10377 if (complain & tf_error
10378 && last_loc != input_location)
10380 if (TREE_CODE (type) == VOID_TYPE)
10381 error ("forming reference to void");
10382 else if (code == POINTER_TYPE)
10383 error ("forming pointer to reference type %qT", type);
10385 error ("forming reference to reference type %qT", type);
10386 last_loc = input_location;
10389 return error_mark_node;
10391 else if (code == POINTER_TYPE)
10393 r = build_pointer_type (type);
10394 if (TREE_CODE (type) == METHOD_TYPE)
10395 r = build_ptrmemfunc_type (r);
10397 else if (TREE_CODE (type) == REFERENCE_TYPE)
10398 /* In C++0x, during template argument substitution, when there is an
10399 attempt to create a reference to a reference type, reference
10400 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10402 "If a template-argument for a template-parameter T names a type
10403 that is a reference to a type A, an attempt to create the type
10404 'lvalue reference to cv T' creates the type 'lvalue reference to
10405 A,' while an attempt to create the type type rvalue reference to
10406 cv T' creates the type T"
10408 r = cp_build_reference_type
10410 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10412 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10413 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10415 if (r != error_mark_node)
10416 /* Will this ever be needed for TYPE_..._TO values? */
10423 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10424 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10428 Type deduction may fail for any of the following
10431 -- Attempting to create "pointer to member of T" when T
10432 is not a class type. */
10433 if (complain & tf_error)
10434 error ("creating pointer to member of non-class type %qT", r);
10435 return error_mark_node;
10437 if (TREE_CODE (type) == REFERENCE_TYPE)
10439 if (complain & tf_error)
10440 error ("creating pointer to member reference type %qT", type);
10441 return error_mark_node;
10443 if (TREE_CODE (type) == VOID_TYPE)
10445 if (complain & tf_error)
10446 error ("creating pointer to member of type void");
10447 return error_mark_node;
10449 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10450 if (TREE_CODE (type) == FUNCTION_TYPE)
10452 /* The type of the implicit object parameter gets its
10453 cv-qualifiers from the FUNCTION_TYPE. */
10455 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10456 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10457 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10461 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10465 case FUNCTION_TYPE:
10470 fntype = tsubst_function_type (t, args, complain, in_decl);
10471 if (fntype == error_mark_node)
10472 return error_mark_node;
10474 /* Substitute the exception specification. */
10475 specs = tsubst_exception_specification (t, args, complain,
10477 if (specs == error_mark_node)
10478 return error_mark_node;
10480 fntype = build_exception_variant (fntype, specs);
10485 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10486 if (domain == error_mark_node)
10487 return error_mark_node;
10489 /* As an optimization, we avoid regenerating the array type if
10490 it will obviously be the same as T. */
10491 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10494 /* These checks should match the ones in grokdeclarator.
10498 The deduction may fail for any of the following reasons:
10500 -- Attempting to create an array with an element type that
10501 is void, a function type, or a reference type, or [DR337]
10502 an abstract class type. */
10503 if (TREE_CODE (type) == VOID_TYPE
10504 || TREE_CODE (type) == FUNCTION_TYPE
10505 || TREE_CODE (type) == REFERENCE_TYPE)
10507 if (complain & tf_error)
10508 error ("creating array of %qT", type);
10509 return error_mark_node;
10511 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10513 if (complain & tf_error)
10514 error ("creating array of %qT, which is an abstract class type",
10516 return error_mark_node;
10519 r = build_cplus_array_type (type, domain);
10521 if (TYPE_USER_ALIGN (t))
10523 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10524 TYPE_USER_ALIGN (r) = 1;
10533 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10534 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10536 if (e1 == error_mark_node || e2 == error_mark_node)
10537 return error_mark_node;
10539 return fold_build2_loc (input_location,
10540 code, TREE_TYPE (t), e1, e2);
10546 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10547 if (e == error_mark_node)
10548 return error_mark_node;
10550 return fold_build1_loc (input_location, code, TREE_TYPE (t), e);
10553 case TYPENAME_TYPE:
10555 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10556 in_decl, /*entering_scope=*/1);
10557 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10558 complain, in_decl);
10560 if (ctx == error_mark_node || f == error_mark_node)
10561 return error_mark_node;
10563 if (!MAYBE_CLASS_TYPE_P (ctx))
10565 if (complain & tf_error)
10566 error ("%qT is not a class, struct, or union type", ctx);
10567 return error_mark_node;
10569 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10571 /* Normally, make_typename_type does not require that the CTX
10572 have complete type in order to allow things like:
10574 template <class T> struct S { typename S<T>::X Y; };
10576 But, such constructs have already been resolved by this
10577 point, so here CTX really should have complete type, unless
10578 it's a partial instantiation. */
10579 if (!(complain & tf_no_class_instantiations))
10580 ctx = complete_type (ctx);
10581 if (!COMPLETE_TYPE_P (ctx))
10583 if (complain & tf_error)
10584 cxx_incomplete_type_error (NULL_TREE, ctx);
10585 return error_mark_node;
10589 f = make_typename_type (ctx, f, typename_type,
10590 (complain & tf_error) | tf_keep_type_decl);
10591 if (f == error_mark_node)
10593 if (TREE_CODE (f) == TYPE_DECL)
10595 complain |= tf_ignore_bad_quals;
10599 if (TREE_CODE (f) != TYPENAME_TYPE)
10601 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10602 error ("%qT resolves to %qT, which is not an enumeration type",
10604 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10605 error ("%qT resolves to %qT, which is is not a class type",
10609 return cp_build_qualified_type_real
10610 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10613 case UNBOUND_CLASS_TEMPLATE:
10615 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10616 in_decl, /*entering_scope=*/1);
10617 tree name = TYPE_IDENTIFIER (t);
10618 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10620 if (ctx == error_mark_node || name == error_mark_node)
10621 return error_mark_node;
10624 parm_list = tsubst_template_parms (parm_list, args, complain);
10625 return make_unbound_class_template (ctx, name, parm_list, complain);
10631 gcc_unreachable ();
10635 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10636 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10637 /*integral_constant_expression_p=*/false);
10638 if (e1 == error_mark_node || e2 == error_mark_node)
10639 return error_mark_node;
10641 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10646 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10647 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10648 if (e1 == error_mark_node || e2 == error_mark_node)
10649 return error_mark_node;
10651 return build_qualified_name (/*type=*/NULL_TREE,
10652 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10659 ++cp_unevaluated_operand;
10660 ++c_inhibit_evaluation_warnings;
10662 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10664 /*integral_constant_expression_p=*/false);
10666 --cp_unevaluated_operand;
10667 --c_inhibit_evaluation_warnings;
10669 type = finish_typeof (type);
10670 return cp_build_qualified_type_real (type,
10672 | cp_type_quals (type),
10676 case DECLTYPE_TYPE:
10680 ++cp_unevaluated_operand;
10681 ++c_inhibit_evaluation_warnings;
10683 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10685 /*integral_constant_expression_p=*/false);
10687 --cp_unevaluated_operand;
10688 --c_inhibit_evaluation_warnings;
10690 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10691 type = lambda_capture_field_type (type);
10692 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10693 type = lambda_return_type (type);
10695 type = finish_decltype_type
10696 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10697 return cp_build_qualified_type_real (type,
10699 | cp_type_quals (type),
10703 case TYPE_ARGUMENT_PACK:
10704 case NONTYPE_ARGUMENT_PACK:
10706 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
10708 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10712 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10714 /* For template nontype argument packs, also substitute into
10716 if (code == NONTYPE_ARGUMENT_PACK)
10717 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10724 sorry ("use of %qs in template", tree_code_name [(int) code]);
10725 return error_mark_node;
10729 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10730 type of the expression on the left-hand side of the "." or "->"
10734 tsubst_baselink (tree baselink, tree object_type,
10735 tree args, tsubst_flags_t complain, tree in_decl)
10738 tree qualifying_scope;
10741 tree template_args = 0;
10742 bool template_id_p = false;
10744 /* A baselink indicates a function from a base class. Both the
10745 BASELINK_ACCESS_BINFO and the base class referenced may
10746 indicate bases of the template class, rather than the
10747 instantiated class. In addition, lookups that were not
10748 ambiguous before may be ambiguous now. Therefore, we perform
10749 the lookup again. */
10750 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10751 qualifying_scope = tsubst (qualifying_scope, args,
10752 complain, in_decl);
10753 fns = BASELINK_FUNCTIONS (baselink);
10754 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
10755 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10757 template_id_p = true;
10758 template_args = TREE_OPERAND (fns, 1);
10759 fns = TREE_OPERAND (fns, 0);
10761 template_args = tsubst_template_args (template_args, args,
10762 complain, in_decl);
10764 name = DECL_NAME (get_first_fn (fns));
10765 if (IDENTIFIER_TYPENAME_P (name))
10766 name = mangle_conv_op_name_for_type (optype);
10767 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10769 return error_mark_node;
10771 /* If lookup found a single function, mark it as used at this
10772 point. (If it lookup found multiple functions the one selected
10773 later by overload resolution will be marked as used at that
10775 if (BASELINK_P (baselink))
10776 fns = BASELINK_FUNCTIONS (baselink);
10777 if (!template_id_p && !really_overloaded_fn (fns))
10778 mark_used (OVL_CURRENT (fns));
10780 /* Add back the template arguments, if present. */
10781 if (BASELINK_P (baselink) && template_id_p)
10782 BASELINK_FUNCTIONS (baselink)
10783 = build_nt (TEMPLATE_ID_EXPR,
10784 BASELINK_FUNCTIONS (baselink),
10786 /* Update the conversion operator type. */
10787 BASELINK_OPTYPE (baselink) = optype;
10790 object_type = current_class_type;
10791 return adjust_result_of_qualified_name_lookup (baselink,
10796 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10797 true if the qualified-id will be a postfix-expression in-and-of
10798 itself; false if more of the postfix-expression follows the
10799 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10803 tsubst_qualified_id (tree qualified_id, tree args,
10804 tsubst_flags_t complain, tree in_decl,
10805 bool done, bool address_p)
10811 tree template_args;
10813 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10815 /* Figure out what name to look up. */
10816 name = TREE_OPERAND (qualified_id, 1);
10817 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10819 is_template = true;
10820 template_args = TREE_OPERAND (name, 1);
10822 template_args = tsubst_template_args (template_args, args,
10823 complain, in_decl);
10824 name = TREE_OPERAND (name, 0);
10828 is_template = false;
10829 template_args = NULL_TREE;
10832 /* Substitute into the qualifying scope. When there are no ARGS, we
10833 are just trying to simplify a non-dependent expression. In that
10834 case the qualifying scope may be dependent, and, in any case,
10835 substituting will not help. */
10836 scope = TREE_OPERAND (qualified_id, 0);
10839 scope = tsubst (scope, args, complain, in_decl);
10840 expr = tsubst_copy (name, args, complain, in_decl);
10845 if (dependent_scope_p (scope))
10846 return build_qualified_name (NULL_TREE, scope, expr,
10847 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10849 if (!BASELINK_P (name) && !DECL_P (expr))
10851 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10853 /* A BIT_NOT_EXPR is used to represent a destructor. */
10854 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10856 error ("qualifying type %qT does not match destructor name ~%qT",
10857 scope, TREE_OPERAND (expr, 0));
10858 expr = error_mark_node;
10861 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10862 /*is_type_p=*/0, false);
10865 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10866 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10867 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10869 if (complain & tf_error)
10871 error ("dependent-name %qE is parsed as a non-type, but "
10872 "instantiation yields a type", qualified_id);
10873 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10875 return error_mark_node;
10881 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10883 /* Remember that there was a reference to this entity. */
10887 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10889 if (complain & tf_error)
10890 qualified_name_lookup_error (scope,
10891 TREE_OPERAND (qualified_id, 1),
10892 expr, input_location);
10893 return error_mark_node;
10897 expr = lookup_template_function (expr, template_args);
10899 if (expr == error_mark_node && complain & tf_error)
10900 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10901 expr, input_location);
10902 else if (TYPE_P (scope))
10904 expr = (adjust_result_of_qualified_name_lookup
10905 (expr, scope, current_class_type));
10906 expr = (finish_qualified_id_expr
10907 (scope, expr, done, address_p,
10908 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10909 /*template_arg_p=*/false));
10912 /* Expressions do not generally have reference type. */
10913 if (TREE_CODE (expr) != SCOPE_REF
10914 /* However, if we're about to form a pointer-to-member, we just
10915 want the referenced member referenced. */
10916 && TREE_CODE (expr) != OFFSET_REF)
10917 expr = convert_from_reference (expr);
10922 /* Like tsubst, but deals with expressions. This function just replaces
10923 template parms; to finish processing the resultant expression, use
10927 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10929 enum tree_code code;
10932 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10935 code = TREE_CODE (t);
10940 r = retrieve_local_specialization (t);
10945 /* This can happen for a parameter name used later in a function
10946 declaration (such as in a late-specified return type). Just
10947 make a dummy decl, since it's only used for its type. */
10948 gcc_assert (cp_unevaluated_operand != 0);
10949 /* We copy T because want to tsubst the PARM_DECL only,
10950 not the following PARM_DECLs that are chained to T. */
10952 r = tsubst_decl (c, args, complain);
10953 /* Give it the template pattern as its context; its true context
10954 hasn't been instantiated yet and this is good enough for
10956 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10959 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10960 r = ARGUMENT_PACK_SELECT_ARG (r);
10969 if (DECL_TEMPLATE_PARM_P (t))
10970 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10971 /* There is no need to substitute into namespace-scope
10973 if (DECL_NAMESPACE_SCOPE_P (t))
10975 /* If ARGS is NULL, then T is known to be non-dependent. */
10976 if (args == NULL_TREE)
10977 return integral_constant_value (t);
10979 /* Unfortunately, we cannot just call lookup_name here.
10982 template <int I> int f() {
10984 struct S { void g() { E e = a; } };
10987 When we instantiate f<7>::S::g(), say, lookup_name is not
10988 clever enough to find f<7>::a. */
10990 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10991 /*entering_scope=*/0);
10993 for (v = TYPE_VALUES (enum_type);
10995 v = TREE_CHAIN (v))
10996 if (TREE_PURPOSE (v) == DECL_NAME (t))
10997 return TREE_VALUE (v);
10999 /* We didn't find the name. That should never happen; if
11000 name-lookup found it during preliminary parsing, we
11001 should find it again here during instantiation. */
11002 gcc_unreachable ();
11007 if (DECL_CONTEXT (t))
11011 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11012 /*entering_scope=*/1);
11013 if (ctx != DECL_CONTEXT (t))
11015 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11018 if (complain & tf_error)
11019 error ("using invalid field %qD", t);
11020 return error_mark_node;
11029 case FUNCTION_DECL:
11030 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11031 || local_variable_p (t))
11032 t = tsubst (t, args, complain, in_decl);
11037 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11039 case TEMPLATE_DECL:
11040 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11041 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11042 args, complain, in_decl);
11043 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11044 return tsubst (t, args, complain, in_decl);
11045 else if (DECL_CLASS_SCOPE_P (t)
11046 && uses_template_parms (DECL_CONTEXT (t)))
11048 /* Template template argument like the following example need
11051 template <template <class> class TT> struct C {};
11052 template <class T> struct D {
11053 template <class U> struct E {};
11058 We are processing the template argument `E' in #1 for
11059 the template instantiation #2. Originally, `E' is a
11060 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11061 have to substitute this with one having context `D<int>'. */
11063 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11064 return lookup_field (context, DECL_NAME(t), 0, false);
11067 /* Ordinary template template argument. */
11071 case REINTERPRET_CAST_EXPR:
11072 case CONST_CAST_EXPR:
11073 case STATIC_CAST_EXPR:
11074 case DYNAMIC_CAST_EXPR:
11077 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11078 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11081 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11083 /* We only want to compute the number of arguments. */
11084 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11085 complain, in_decl);
11088 if (TREE_CODE (expanded) == TREE_VEC)
11089 len = TREE_VEC_LENGTH (expanded);
11091 if (expanded == error_mark_node)
11092 return error_mark_node;
11093 else if (PACK_EXPANSION_P (expanded)
11094 || (TREE_CODE (expanded) == TREE_VEC
11096 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11098 if (TREE_CODE (expanded) == TREE_VEC)
11099 expanded = TREE_VEC_ELT (expanded, len - 1);
11101 if (TYPE_P (expanded))
11102 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11103 complain & tf_error);
11105 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11106 complain & tf_error);
11109 return build_int_cst (size_type_node, len);
11115 case TRUTH_NOT_EXPR:
11118 case UNARY_PLUS_EXPR: /* Unary + */
11123 case REALPART_EXPR:
11124 case IMAGPART_EXPR:
11126 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11127 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11129 case COMPONENT_REF:
11134 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11135 name = TREE_OPERAND (t, 1);
11136 if (TREE_CODE (name) == BIT_NOT_EXPR)
11138 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11139 complain, in_decl);
11140 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11142 else if (TREE_CODE (name) == SCOPE_REF
11143 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11145 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11146 complain, in_decl);
11147 name = TREE_OPERAND (name, 1);
11148 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11149 complain, in_decl);
11150 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11151 name = build_qualified_name (/*type=*/NULL_TREE,
11153 /*template_p=*/false);
11155 else if (TREE_CODE (name) == BASELINK)
11156 name = tsubst_baselink (name,
11157 non_reference (TREE_TYPE (object)),
11161 name = tsubst_copy (name, args, complain, in_decl);
11162 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11168 case TRUNC_DIV_EXPR:
11169 case CEIL_DIV_EXPR:
11170 case FLOOR_DIV_EXPR:
11171 case ROUND_DIV_EXPR:
11172 case EXACT_DIV_EXPR:
11176 case TRUNC_MOD_EXPR:
11177 case FLOOR_MOD_EXPR:
11178 case TRUTH_ANDIF_EXPR:
11179 case TRUTH_ORIF_EXPR:
11180 case TRUTH_AND_EXPR:
11181 case TRUTH_OR_EXPR:
11194 case COMPOUND_EXPR:
11197 case PREDECREMENT_EXPR:
11198 case PREINCREMENT_EXPR:
11199 case POSTDECREMENT_EXPR:
11200 case POSTINCREMENT_EXPR:
11202 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11203 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11206 return build_qualified_name (/*type=*/NULL_TREE,
11207 tsubst_copy (TREE_OPERAND (t, 0),
11208 args, complain, in_decl),
11209 tsubst_copy (TREE_OPERAND (t, 1),
11210 args, complain, in_decl),
11211 QUALIFIED_NAME_IS_TEMPLATE (t));
11216 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11217 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11218 NULL_TREE, NULL_TREE);
11222 int n = VL_EXP_OPERAND_LENGTH (t);
11223 tree result = build_vl_exp (CALL_EXPR, n);
11225 for (i = 0; i < n; i++)
11226 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11227 complain, in_decl);
11233 case PSEUDO_DTOR_EXPR:
11236 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11237 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11238 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11239 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11246 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11247 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11248 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11249 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11256 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11257 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11258 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11259 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11263 case TEMPLATE_ID_EXPR:
11265 /* Substituted template arguments */
11266 tree fn = TREE_OPERAND (t, 0);
11267 tree targs = TREE_OPERAND (t, 1);
11269 fn = tsubst_copy (fn, args, complain, in_decl);
11271 targs = tsubst_template_args (targs, args, complain, in_decl);
11273 return lookup_template_function (fn, targs);
11278 tree purpose, value, chain;
11280 if (t == void_list_node)
11283 purpose = TREE_PURPOSE (t);
11285 purpose = tsubst_copy (purpose, args, complain, in_decl);
11286 value = TREE_VALUE (t);
11288 value = tsubst_copy (value, args, complain, in_decl);
11289 chain = TREE_CHAIN (t);
11290 if (chain && chain != void_type_node)
11291 chain = tsubst_copy (chain, args, complain, in_decl);
11292 if (purpose == TREE_PURPOSE (t)
11293 && value == TREE_VALUE (t)
11294 && chain == TREE_CHAIN (t))
11296 return tree_cons (purpose, value, chain);
11301 case ENUMERAL_TYPE:
11303 case TEMPLATE_TYPE_PARM:
11304 case TEMPLATE_TEMPLATE_PARM:
11305 case BOUND_TEMPLATE_TEMPLATE_PARM:
11306 case TEMPLATE_PARM_INDEX:
11308 case REFERENCE_TYPE:
11310 case FUNCTION_TYPE:
11313 case TYPENAME_TYPE:
11314 case UNBOUND_CLASS_TEMPLATE:
11316 case DECLTYPE_TYPE:
11318 return tsubst (t, args, complain, in_decl);
11320 case IDENTIFIER_NODE:
11321 if (IDENTIFIER_TYPENAME_P (t))
11323 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11324 return mangle_conv_op_name_for_type (new_type);
11330 /* This is handled by tsubst_copy_and_build. */
11331 gcc_unreachable ();
11334 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11336 tsubst (TREE_TYPE (t), args, complain, in_decl));
11338 case CLEANUP_POINT_EXPR:
11339 /* We shouldn't have built any of these during initial template
11340 generation. Instead, they should be built during instantiation
11341 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11342 gcc_unreachable ();
11346 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11347 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11348 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11349 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11350 mark_used (TREE_OPERAND (r, 1));
11353 case EXPR_PACK_EXPANSION:
11354 error ("invalid use of pack expansion expression");
11355 return error_mark_node;
11357 case NONTYPE_ARGUMENT_PACK:
11358 error ("use %<...%> to expand argument pack");
11359 return error_mark_node;
11366 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11369 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11372 tree new_clauses = NULL, nc, oc;
11374 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11376 nc = copy_node (oc);
11377 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11380 switch (OMP_CLAUSE_CODE (nc))
11382 case OMP_CLAUSE_LASTPRIVATE:
11383 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11385 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11386 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11387 in_decl, /*integral_constant_expression_p=*/false);
11388 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11389 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11392 case OMP_CLAUSE_PRIVATE:
11393 case OMP_CLAUSE_SHARED:
11394 case OMP_CLAUSE_FIRSTPRIVATE:
11395 case OMP_CLAUSE_REDUCTION:
11396 case OMP_CLAUSE_COPYIN:
11397 case OMP_CLAUSE_COPYPRIVATE:
11398 case OMP_CLAUSE_IF:
11399 case OMP_CLAUSE_NUM_THREADS:
11400 case OMP_CLAUSE_SCHEDULE:
11401 case OMP_CLAUSE_COLLAPSE:
11402 OMP_CLAUSE_OPERAND (nc, 0)
11403 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11404 in_decl, /*integral_constant_expression_p=*/false);
11406 case OMP_CLAUSE_NOWAIT:
11407 case OMP_CLAUSE_ORDERED:
11408 case OMP_CLAUSE_DEFAULT:
11409 case OMP_CLAUSE_UNTIED:
11412 gcc_unreachable ();
11416 return finish_omp_clauses (nreverse (new_clauses));
11419 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11422 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11425 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11427 tree purpose, value, chain;
11432 if (TREE_CODE (t) != TREE_LIST)
11433 return tsubst_copy_and_build (t, args, complain, in_decl,
11434 /*function_p=*/false,
11435 /*integral_constant_expression_p=*/false);
11437 if (t == void_list_node)
11440 purpose = TREE_PURPOSE (t);
11442 purpose = RECUR (purpose);
11443 value = TREE_VALUE (t);
11444 if (value && TREE_CODE (value) != LABEL_DECL)
11445 value = RECUR (value);
11446 chain = TREE_CHAIN (t);
11447 if (chain && chain != void_type_node)
11448 chain = RECUR (chain);
11449 return tree_cons (purpose, value, chain);
11453 /* Substitute one OMP_FOR iterator. */
11456 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11457 tree condv, tree incrv, tree *clauses,
11458 tree args, tsubst_flags_t complain, tree in_decl,
11459 bool integral_constant_expression_p)
11461 #define RECUR(NODE) \
11462 tsubst_expr ((NODE), args, complain, in_decl, \
11463 integral_constant_expression_p)
11464 tree decl, init, cond, incr, auto_node;
11466 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11467 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11468 decl = RECUR (TREE_OPERAND (init, 0));
11469 init = TREE_OPERAND (init, 1);
11470 auto_node = type_uses_auto (TREE_TYPE (decl));
11471 if (auto_node && init)
11473 tree init_expr = init;
11474 if (TREE_CODE (init_expr) == DECL_EXPR)
11475 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11476 init_expr = RECUR (init_expr);
11478 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11480 gcc_assert (!type_dependent_expression_p (decl));
11482 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11484 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11485 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11486 if (TREE_CODE (incr) == MODIFY_EXPR)
11487 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11488 RECUR (TREE_OPERAND (incr, 1)),
11491 incr = RECUR (incr);
11492 TREE_VEC_ELT (declv, i) = decl;
11493 TREE_VEC_ELT (initv, i) = init;
11494 TREE_VEC_ELT (condv, i) = cond;
11495 TREE_VEC_ELT (incrv, i) = incr;
11499 if (init && TREE_CODE (init) != DECL_EXPR)
11502 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11504 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11505 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11506 && OMP_CLAUSE_DECL (c) == decl)
11508 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11509 && OMP_CLAUSE_DECL (c) == decl)
11510 error ("iteration variable %qD should not be firstprivate", decl);
11511 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11512 && OMP_CLAUSE_DECL (c) == decl)
11513 error ("iteration variable %qD should not be reduction", decl);
11517 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11518 OMP_CLAUSE_DECL (c) = decl;
11519 c = finish_omp_clauses (c);
11522 OMP_CLAUSE_CHAIN (c) = *clauses;
11527 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11528 if (COMPARISON_CLASS_P (cond))
11529 cond = build2 (TREE_CODE (cond), boolean_type_node,
11530 RECUR (TREE_OPERAND (cond, 0)),
11531 RECUR (TREE_OPERAND (cond, 1)));
11533 cond = RECUR (cond);
11534 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11535 switch (TREE_CODE (incr))
11537 case PREINCREMENT_EXPR:
11538 case PREDECREMENT_EXPR:
11539 case POSTINCREMENT_EXPR:
11540 case POSTDECREMENT_EXPR:
11541 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11542 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11545 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11546 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11548 tree rhs = TREE_OPERAND (incr, 1);
11549 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11550 RECUR (TREE_OPERAND (incr, 0)),
11551 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11552 RECUR (TREE_OPERAND (rhs, 0)),
11553 RECUR (TREE_OPERAND (rhs, 1))));
11556 incr = RECUR (incr);
11559 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11560 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11562 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11563 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11564 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11565 TREE_TYPE (decl), lhs,
11566 RECUR (TREE_OPERAND (incr, 2))));
11568 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11569 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11570 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11572 tree rhs = TREE_OPERAND (incr, 2);
11573 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11574 RECUR (TREE_OPERAND (incr, 0)),
11575 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11576 RECUR (TREE_OPERAND (rhs, 0)),
11577 RECUR (TREE_OPERAND (rhs, 1))));
11580 incr = RECUR (incr);
11583 incr = RECUR (incr);
11587 TREE_VEC_ELT (declv, i) = decl;
11588 TREE_VEC_ELT (initv, i) = init;
11589 TREE_VEC_ELT (condv, i) = cond;
11590 TREE_VEC_ELT (incrv, i) = incr;
11594 /* Like tsubst_copy for expressions, etc. but also does semantic
11598 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11599 bool integral_constant_expression_p)
11601 #define RECUR(NODE) \
11602 tsubst_expr ((NODE), args, complain, in_decl, \
11603 integral_constant_expression_p)
11607 if (t == NULL_TREE || t == error_mark_node)
11610 if (EXPR_HAS_LOCATION (t))
11611 input_location = EXPR_LOCATION (t);
11612 if (STATEMENT_CODE_P (TREE_CODE (t)))
11613 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11615 switch (TREE_CODE (t))
11617 case STATEMENT_LIST:
11619 tree_stmt_iterator i;
11620 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11621 RECUR (tsi_stmt (i));
11625 case CTOR_INITIALIZER:
11626 finish_mem_initializers (tsubst_initializer_list
11627 (TREE_OPERAND (t, 0), args));
11631 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11635 tmp = RECUR (EXPR_STMT_EXPR (t));
11636 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11637 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11639 finish_expr_stmt (tmp);
11643 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11651 decl = DECL_EXPR_DECL (t);
11652 if (TREE_CODE (decl) == LABEL_DECL)
11653 finish_label_decl (DECL_NAME (decl));
11654 else if (TREE_CODE (decl) == USING_DECL)
11656 tree scope = USING_DECL_SCOPE (decl);
11657 tree name = DECL_NAME (decl);
11660 scope = RECUR (scope);
11661 decl = lookup_qualified_name (scope, name,
11662 /*is_type_p=*/false,
11663 /*complain=*/false);
11664 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11665 qualified_name_lookup_error (scope, name, decl, input_location);
11667 do_local_using_decl (decl, scope, name);
11671 init = DECL_INITIAL (decl);
11672 decl = tsubst (decl, args, complain, in_decl);
11673 if (decl != error_mark_node)
11675 /* By marking the declaration as instantiated, we avoid
11676 trying to instantiate it. Since instantiate_decl can't
11677 handle local variables, and since we've already done
11678 all that needs to be done, that's the right thing to
11680 if (TREE_CODE (decl) == VAR_DECL)
11681 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11682 if (TREE_CODE (decl) == VAR_DECL
11683 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11684 /* Anonymous aggregates are a special case. */
11685 finish_anon_union (decl);
11688 maybe_push_decl (decl);
11689 if (TREE_CODE (decl) == VAR_DECL
11690 && DECL_PRETTY_FUNCTION_P (decl))
11692 /* For __PRETTY_FUNCTION__ we have to adjust the
11694 const char *const name
11695 = cxx_printable_name (current_function_decl, 2);
11696 init = cp_fname_init (name, &TREE_TYPE (decl));
11700 tree t = RECUR (init);
11704 /* If we had an initializer but it
11705 instantiated to nothing,
11706 value-initialize the object. This will
11707 only occur when the initializer was a
11708 pack expansion where the parameter packs
11709 used in that expansion were of length
11711 init = build_value_init (TREE_TYPE (decl),
11713 if (TREE_CODE (init) == AGGR_INIT_EXPR)
11714 init = get_target_expr (init);
11720 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11725 /* A DECL_EXPR can also be used as an expression, in the condition
11726 clause of an if/for/while construct. */
11731 stmt = begin_for_stmt ();
11732 RECUR (FOR_INIT_STMT (t));
11733 finish_for_init_stmt (stmt);
11734 tmp = RECUR (FOR_COND (t));
11735 finish_for_cond (tmp, stmt);
11736 tmp = RECUR (FOR_EXPR (t));
11737 finish_for_expr (tmp, stmt);
11738 RECUR (FOR_BODY (t));
11739 finish_for_stmt (stmt);
11743 stmt = begin_while_stmt ();
11744 tmp = RECUR (WHILE_COND (t));
11745 finish_while_stmt_cond (tmp, stmt);
11746 RECUR (WHILE_BODY (t));
11747 finish_while_stmt (stmt);
11751 stmt = begin_do_stmt ();
11752 RECUR (DO_BODY (t));
11753 finish_do_body (stmt);
11754 tmp = RECUR (DO_COND (t));
11755 finish_do_stmt (tmp, stmt);
11759 stmt = begin_if_stmt ();
11760 tmp = RECUR (IF_COND (t));
11761 finish_if_stmt_cond (tmp, stmt);
11762 RECUR (THEN_CLAUSE (t));
11763 finish_then_clause (stmt);
11765 if (ELSE_CLAUSE (t))
11767 begin_else_clause (stmt);
11768 RECUR (ELSE_CLAUSE (t));
11769 finish_else_clause (stmt);
11772 finish_if_stmt (stmt);
11776 if (BIND_EXPR_BODY_BLOCK (t))
11777 stmt = begin_function_body ();
11779 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11780 ? BCS_TRY_BLOCK : 0);
11782 RECUR (BIND_EXPR_BODY (t));
11784 if (BIND_EXPR_BODY_BLOCK (t))
11785 finish_function_body (stmt);
11787 finish_compound_stmt (stmt);
11791 finish_break_stmt ();
11794 case CONTINUE_STMT:
11795 finish_continue_stmt ();
11799 stmt = begin_switch_stmt ();
11800 tmp = RECUR (SWITCH_STMT_COND (t));
11801 finish_switch_cond (tmp, stmt);
11802 RECUR (SWITCH_STMT_BODY (t));
11803 finish_switch_stmt (stmt);
11806 case CASE_LABEL_EXPR:
11807 finish_case_label (EXPR_LOCATION (t),
11808 RECUR (CASE_LOW (t)),
11809 RECUR (CASE_HIGH (t)));
11814 tree decl = LABEL_EXPR_LABEL (t);
11817 label = finish_label_stmt (DECL_NAME (decl));
11818 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11819 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11824 tmp = GOTO_DESTINATION (t);
11825 if (TREE_CODE (tmp) != LABEL_DECL)
11826 /* Computed goto's must be tsubst'd into. On the other hand,
11827 non-computed gotos must not be; the identifier in question
11828 will have no binding. */
11831 tmp = DECL_NAME (tmp);
11832 finish_goto_stmt (tmp);
11836 tmp = finish_asm_stmt
11837 (ASM_VOLATILE_P (t),
11838 RECUR (ASM_STRING (t)),
11839 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11840 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11841 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11842 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11844 tree asm_expr = tmp;
11845 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11846 asm_expr = TREE_OPERAND (asm_expr, 0);
11847 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11854 stmt = begin_try_block ();
11855 RECUR (TRY_STMTS (t));
11856 finish_cleanup_try_block (stmt);
11857 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11861 tree compound_stmt = NULL_TREE;
11863 if (FN_TRY_BLOCK_P (t))
11864 stmt = begin_function_try_block (&compound_stmt);
11866 stmt = begin_try_block ();
11868 RECUR (TRY_STMTS (t));
11870 if (FN_TRY_BLOCK_P (t))
11871 finish_function_try_block (stmt);
11873 finish_try_block (stmt);
11875 RECUR (TRY_HANDLERS (t));
11876 if (FN_TRY_BLOCK_P (t))
11877 finish_function_handler_sequence (stmt, compound_stmt);
11879 finish_handler_sequence (stmt);
11885 tree decl = HANDLER_PARMS (t);
11889 decl = tsubst (decl, args, complain, in_decl);
11890 /* Prevent instantiate_decl from trying to instantiate
11891 this variable. We've already done all that needs to be
11893 if (decl != error_mark_node)
11894 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11896 stmt = begin_handler ();
11897 finish_handler_parms (decl, stmt);
11898 RECUR (HANDLER_BODY (t));
11899 finish_handler (stmt);
11904 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11907 case STATIC_ASSERT:
11910 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11913 /*integral_constant_expression_p=*/true);
11914 finish_static_assert (condition,
11915 STATIC_ASSERT_MESSAGE (t),
11916 STATIC_ASSERT_SOURCE_LOCATION (t),
11917 /*member_p=*/false);
11922 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11923 args, complain, in_decl);
11924 stmt = begin_omp_parallel ();
11925 RECUR (OMP_PARALLEL_BODY (t));
11926 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11927 = OMP_PARALLEL_COMBINED (t);
11931 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11932 args, complain, in_decl);
11933 stmt = begin_omp_task ();
11934 RECUR (OMP_TASK_BODY (t));
11935 finish_omp_task (tmp, stmt);
11940 tree clauses, body, pre_body;
11941 tree declv, initv, condv, incrv;
11944 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11945 args, complain, in_decl);
11946 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11947 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11948 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11949 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11951 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11952 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11953 &clauses, args, complain, in_decl,
11954 integral_constant_expression_p);
11956 stmt = begin_omp_structured_block ();
11958 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11959 if (TREE_VEC_ELT (initv, i) == NULL
11960 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11961 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11962 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11964 tree init = RECUR (TREE_VEC_ELT (initv, i));
11965 gcc_assert (init == TREE_VEC_ELT (declv, i));
11966 TREE_VEC_ELT (initv, i) = NULL_TREE;
11970 tree decl_expr = TREE_VEC_ELT (initv, i);
11971 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11972 gcc_assert (init != NULL);
11973 TREE_VEC_ELT (initv, i) = RECUR (init);
11974 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11976 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11979 pre_body = push_stmt_list ();
11980 RECUR (OMP_FOR_PRE_BODY (t));
11981 pre_body = pop_stmt_list (pre_body);
11983 body = push_stmt_list ();
11984 RECUR (OMP_FOR_BODY (t));
11985 body = pop_stmt_list (body);
11987 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11988 body, pre_body, clauses);
11990 add_stmt (finish_omp_structured_block (stmt));
11996 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11997 stmt = push_stmt_list ();
11998 RECUR (OMP_BODY (t));
11999 stmt = pop_stmt_list (stmt);
12002 OMP_BODY (t) = stmt;
12003 OMP_CLAUSES (t) = tmp;
12011 stmt = push_stmt_list ();
12012 RECUR (OMP_BODY (t));
12013 stmt = pop_stmt_list (stmt);
12016 OMP_BODY (t) = stmt;
12021 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12023 tree op1 = TREE_OPERAND (t, 1);
12024 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12025 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12026 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12030 case EXPR_PACK_EXPANSION:
12031 error ("invalid use of pack expansion expression");
12032 return error_mark_node;
12034 case NONTYPE_ARGUMENT_PACK:
12035 error ("use %<...%> to expand argument pack");
12036 return error_mark_node;
12039 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12041 return tsubst_copy_and_build (t, args, complain, in_decl,
12042 /*function_p=*/false,
12043 integral_constant_expression_p);
12050 /* T is a postfix-expression that is not being used in a function
12051 call. Return the substituted version of T. */
12054 tsubst_non_call_postfix_expression (tree t, tree args,
12055 tsubst_flags_t complain,
12058 if (TREE_CODE (t) == SCOPE_REF)
12059 t = tsubst_qualified_id (t, args, complain, in_decl,
12060 /*done=*/false, /*address_p=*/false);
12062 t = tsubst_copy_and_build (t, args, complain, in_decl,
12063 /*function_p=*/false,
12064 /*integral_constant_expression_p=*/false);
12069 /* Like tsubst but deals with expressions and performs semantic
12070 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12073 tsubst_copy_and_build (tree t,
12075 tsubst_flags_t complain,
12078 bool integral_constant_expression_p)
12080 #define RECUR(NODE) \
12081 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12082 /*function_p=*/false, \
12083 integral_constant_expression_p)
12087 if (t == NULL_TREE || t == error_mark_node)
12090 switch (TREE_CODE (t))
12094 /* Fall through. */
12095 case IDENTIFIER_NODE:
12099 bool non_integral_constant_expression_p;
12100 const char *error_msg;
12102 if (IDENTIFIER_TYPENAME_P (t))
12104 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12105 t = mangle_conv_op_name_for_type (new_type);
12108 /* Look up the name. */
12109 decl = lookup_name (t);
12111 /* By convention, expressions use ERROR_MARK_NODE to indicate
12112 failure, not NULL_TREE. */
12113 if (decl == NULL_TREE)
12114 decl = error_mark_node;
12116 decl = finish_id_expression (t, decl, NULL_TREE,
12118 integral_constant_expression_p,
12119 /*allow_non_integral_constant_expression_p=*/false,
12120 &non_integral_constant_expression_p,
12121 /*template_p=*/false,
12123 /*address_p=*/false,
12124 /*template_arg_p=*/false,
12129 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12130 decl = unqualified_name_lookup_error (decl);
12134 case TEMPLATE_ID_EXPR:
12137 tree templ = RECUR (TREE_OPERAND (t, 0));
12138 tree targs = TREE_OPERAND (t, 1);
12141 targs = tsubst_template_args (targs, args, complain, in_decl);
12143 if (TREE_CODE (templ) == COMPONENT_REF)
12145 object = TREE_OPERAND (templ, 0);
12146 templ = TREE_OPERAND (templ, 1);
12149 object = NULL_TREE;
12150 templ = lookup_template_function (templ, targs);
12153 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12154 object, templ, NULL_TREE);
12156 return baselink_for_fns (templ);
12161 tree r = RECUR (TREE_OPERAND (t, 0));
12163 if (REFERENCE_REF_P (t))
12165 /* A type conversion to reference type will be enclosed in
12166 such an indirect ref, but the substitution of the cast
12167 will have also added such an indirect ref. */
12168 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12169 r = convert_from_reference (r);
12172 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12178 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12179 RECUR (TREE_OPERAND (t, 0)));
12182 case REINTERPRET_CAST_EXPR:
12183 case CONST_CAST_EXPR:
12184 case DYNAMIC_CAST_EXPR:
12185 case STATIC_CAST_EXPR:
12190 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12191 if (integral_constant_expression_p
12192 && !cast_valid_in_integral_constant_expression_p (type))
12194 if (complain & tf_error)
12195 error ("a cast to a type other than an integral or "
12196 "enumeration type cannot appear in a constant-expression");
12197 return error_mark_node;
12200 op = RECUR (TREE_OPERAND (t, 0));
12202 switch (TREE_CODE (t))
12205 return build_functional_cast (type, op, complain);
12206 case REINTERPRET_CAST_EXPR:
12207 return build_reinterpret_cast (type, op, complain);
12208 case CONST_CAST_EXPR:
12209 return build_const_cast (type, op, complain);
12210 case DYNAMIC_CAST_EXPR:
12211 return build_dynamic_cast (type, op, complain);
12212 case STATIC_CAST_EXPR:
12213 return build_static_cast (type, op, complain);
12215 gcc_unreachable ();
12219 case POSTDECREMENT_EXPR:
12220 case POSTINCREMENT_EXPR:
12221 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12222 args, complain, in_decl);
12223 return build_x_unary_op (TREE_CODE (t), op1, complain);
12225 case PREDECREMENT_EXPR:
12226 case PREINCREMENT_EXPR:
12230 case TRUTH_NOT_EXPR:
12231 case UNARY_PLUS_EXPR: /* Unary + */
12232 case REALPART_EXPR:
12233 case IMAGPART_EXPR:
12234 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12238 op1 = TREE_OPERAND (t, 0);
12239 if (TREE_CODE (op1) == SCOPE_REF)
12240 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12241 /*done=*/true, /*address_p=*/true);
12243 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12245 if (TREE_CODE (op1) == LABEL_DECL)
12246 return finish_label_address_expr (DECL_NAME (op1),
12247 EXPR_LOCATION (op1));
12248 return build_x_unary_op (ADDR_EXPR, op1, complain);
12253 case TRUNC_DIV_EXPR:
12254 case CEIL_DIV_EXPR:
12255 case FLOOR_DIV_EXPR:
12256 case ROUND_DIV_EXPR:
12257 case EXACT_DIV_EXPR:
12261 case TRUNC_MOD_EXPR:
12262 case FLOOR_MOD_EXPR:
12263 case TRUTH_ANDIF_EXPR:
12264 case TRUTH_ORIF_EXPR:
12265 case TRUTH_AND_EXPR:
12266 case TRUTH_OR_EXPR:
12281 return build_x_binary_op
12283 RECUR (TREE_OPERAND (t, 0)),
12284 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12286 : TREE_CODE (TREE_OPERAND (t, 0))),
12287 RECUR (TREE_OPERAND (t, 1)),
12288 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12290 : TREE_CODE (TREE_OPERAND (t, 1))),
12291 /*overloaded_p=*/NULL,
12295 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12296 /*address_p=*/false);
12298 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12299 args, complain, in_decl);
12300 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12303 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12304 return tsubst_copy (t, args, complain, in_decl);
12308 op1 = TREE_OPERAND (t, 0);
12311 /* When there are no ARGS, we are trying to evaluate a
12312 non-dependent expression from the parser. Trying to do
12313 the substitutions may not work. */
12315 op1 = TREE_TYPE (op1);
12319 ++cp_unevaluated_operand;
12320 ++c_inhibit_evaluation_warnings;
12321 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12322 /*function_p=*/false,
12323 /*integral_constant_expression_p=*/false);
12324 --cp_unevaluated_operand;
12325 --c_inhibit_evaluation_warnings;
12328 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12329 complain & tf_error);
12331 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12332 complain & tf_error);
12334 case NOEXCEPT_EXPR:
12335 op1 = TREE_OPERAND (t, 0);
12336 ++cp_unevaluated_operand;
12337 ++c_inhibit_evaluation_warnings;
12338 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12339 /*function_p=*/false,
12340 /*integral_constant_expression_p=*/false);
12341 --cp_unevaluated_operand;
12342 --c_inhibit_evaluation_warnings;
12343 return finish_noexcept_expr (op1, complain);
12347 tree r = build_x_modify_expr
12348 (RECUR (TREE_OPERAND (t, 0)),
12349 TREE_CODE (TREE_OPERAND (t, 1)),
12350 RECUR (TREE_OPERAND (t, 2)),
12352 /* TREE_NO_WARNING must be set if either the expression was
12353 parenthesized or it uses an operator such as >>= rather
12354 than plain assignment. In the former case, it was already
12355 set and must be copied. In the latter case,
12356 build_x_modify_expr sets it and it must not be reset
12358 if (TREE_NO_WARNING (t))
12359 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12364 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12365 args, complain, in_decl);
12366 /* Remember that there was a reference to this entity. */
12369 return build_x_arrow (op1);
12373 tree placement = RECUR (TREE_OPERAND (t, 0));
12374 tree init = RECUR (TREE_OPERAND (t, 3));
12375 VEC(tree,gc) *placement_vec;
12376 VEC(tree,gc) *init_vec;
12379 if (placement == NULL_TREE)
12380 placement_vec = NULL;
12383 placement_vec = make_tree_vector ();
12384 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12385 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12388 /* If there was an initializer in the original tree, but it
12389 instantiated to an empty list, then we should pass a
12390 non-NULL empty vector to tell build_new that it was an
12391 empty initializer() rather than no initializer. This can
12392 only happen when the initializer is a pack expansion whose
12393 parameter packs are of length zero. */
12394 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12398 init_vec = make_tree_vector ();
12399 if (init == void_zero_node)
12400 gcc_assert (init_vec != NULL);
12403 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12404 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12408 ret = build_new (&placement_vec,
12409 RECUR (TREE_OPERAND (t, 1)),
12410 RECUR (TREE_OPERAND (t, 2)),
12412 NEW_EXPR_USE_GLOBAL (t),
12415 if (placement_vec != NULL)
12416 release_tree_vector (placement_vec);
12417 if (init_vec != NULL)
12418 release_tree_vector (init_vec);
12424 return delete_sanity
12425 (RECUR (TREE_OPERAND (t, 0)),
12426 RECUR (TREE_OPERAND (t, 1)),
12427 DELETE_EXPR_USE_VEC (t),
12428 DELETE_EXPR_USE_GLOBAL (t));
12430 case COMPOUND_EXPR:
12431 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12432 RECUR (TREE_OPERAND (t, 1)),
12438 VEC(tree,gc) *call_args;
12439 unsigned int nargs, i;
12444 function = CALL_EXPR_FN (t);
12445 /* When we parsed the expression, we determined whether or
12446 not Koenig lookup should be performed. */
12447 koenig_p = KOENIG_LOOKUP_P (t);
12448 if (TREE_CODE (function) == SCOPE_REF)
12450 qualified_p = true;
12451 function = tsubst_qualified_id (function, args, complain, in_decl,
12453 /*address_p=*/false);
12457 if (TREE_CODE (function) == COMPONENT_REF)
12459 tree op = TREE_OPERAND (function, 1);
12461 qualified_p = (TREE_CODE (op) == SCOPE_REF
12462 || (BASELINK_P (op)
12463 && BASELINK_QUALIFIED_P (op)));
12466 qualified_p = false;
12468 function = tsubst_copy_and_build (function, args, complain,
12471 integral_constant_expression_p);
12473 if (BASELINK_P (function))
12474 qualified_p = true;
12477 nargs = call_expr_nargs (t);
12478 call_args = make_tree_vector ();
12479 for (i = 0; i < nargs; ++i)
12481 tree arg = CALL_EXPR_ARG (t, i);
12483 if (!PACK_EXPANSION_P (arg))
12484 VEC_safe_push (tree, gc, call_args,
12485 RECUR (CALL_EXPR_ARG (t, i)));
12488 /* Expand the pack expansion and push each entry onto
12490 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12491 if (TREE_CODE (arg) == TREE_VEC)
12493 unsigned int len, j;
12495 len = TREE_VEC_LENGTH (arg);
12496 for (j = 0; j < len; ++j)
12498 tree value = TREE_VEC_ELT (arg, j);
12499 if (value != NULL_TREE)
12500 value = convert_from_reference (value);
12501 VEC_safe_push (tree, gc, call_args, value);
12506 /* A partial substitution. Add one entry. */
12507 VEC_safe_push (tree, gc, call_args, arg);
12512 /* We do not perform argument-dependent lookup if normal
12513 lookup finds a non-function, in accordance with the
12514 expected resolution of DR 218. */
12516 && ((is_overloaded_fn (function)
12517 /* If lookup found a member function, the Koenig lookup is
12518 not appropriate, even if an unqualified-name was used
12519 to denote the function. */
12520 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12521 || TREE_CODE (function) == IDENTIFIER_NODE)
12522 /* Only do this when substitution turns a dependent call
12523 into a non-dependent call. */
12524 && type_dependent_expression_p_push (t)
12525 && !any_type_dependent_arguments_p (call_args))
12526 function = perform_koenig_lookup (function, call_args);
12528 if (TREE_CODE (function) == IDENTIFIER_NODE)
12530 unqualified_name_lookup_error (function);
12531 release_tree_vector (call_args);
12532 return error_mark_node;
12535 /* Remember that there was a reference to this entity. */
12536 if (DECL_P (function))
12537 mark_used (function);
12539 if (TREE_CODE (function) == OFFSET_REF)
12540 ret = build_offset_ref_call_from_tree (function, &call_args);
12541 else if (TREE_CODE (function) == COMPONENT_REF)
12543 tree instance = TREE_OPERAND (function, 0);
12544 tree fn = TREE_OPERAND (function, 1);
12546 if (processing_template_decl
12547 && (type_dependent_expression_p (instance)
12548 || (!BASELINK_P (fn)
12549 && TREE_CODE (fn) != FIELD_DECL)
12550 || type_dependent_expression_p (fn)
12551 || any_type_dependent_arguments_p (call_args)))
12552 ret = build_nt_call_vec (function, call_args);
12553 else if (!BASELINK_P (fn))
12554 ret = finish_call_expr (function, &call_args,
12555 /*disallow_virtual=*/false,
12556 /*koenig_p=*/false,
12559 ret = (build_new_method_call
12561 &call_args, NULL_TREE,
12562 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12567 ret = finish_call_expr (function, &call_args,
12568 /*disallow_virtual=*/qualified_p,
12572 release_tree_vector (call_args);
12578 return build_x_conditional_expr
12579 (RECUR (TREE_OPERAND (t, 0)),
12580 RECUR (TREE_OPERAND (t, 1)),
12581 RECUR (TREE_OPERAND (t, 2)),
12584 case PSEUDO_DTOR_EXPR:
12585 return finish_pseudo_destructor_expr
12586 (RECUR (TREE_OPERAND (t, 0)),
12587 RECUR (TREE_OPERAND (t, 1)),
12588 RECUR (TREE_OPERAND (t, 2)));
12592 tree purpose, value, chain;
12594 if (t == void_list_node)
12597 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12598 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12600 /* We have pack expansions, so expand those and
12601 create a new list out of it. */
12602 tree purposevec = NULL_TREE;
12603 tree valuevec = NULL_TREE;
12607 /* Expand the argument expressions. */
12608 if (TREE_PURPOSE (t))
12609 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12610 complain, in_decl);
12611 if (TREE_VALUE (t))
12612 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12613 complain, in_decl);
12615 /* Build the rest of the list. */
12616 chain = TREE_CHAIN (t);
12617 if (chain && chain != void_type_node)
12618 chain = RECUR (chain);
12620 /* Determine the number of arguments. */
12621 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12623 len = TREE_VEC_LENGTH (purposevec);
12624 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12626 else if (TREE_CODE (valuevec) == TREE_VEC)
12627 len = TREE_VEC_LENGTH (valuevec);
12630 /* Since we only performed a partial substitution into
12631 the argument pack, we only return a single list
12633 if (purposevec == TREE_PURPOSE (t)
12634 && valuevec == TREE_VALUE (t)
12635 && chain == TREE_CHAIN (t))
12638 return tree_cons (purposevec, valuevec, chain);
12641 /* Convert the argument vectors into a TREE_LIST */
12645 /* Grab the Ith values. */
12647 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12650 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12653 /* Build the list (backwards). */
12654 chain = tree_cons (purpose, value, chain);
12660 purpose = TREE_PURPOSE (t);
12662 purpose = RECUR (purpose);
12663 value = TREE_VALUE (t);
12665 value = RECUR (value);
12666 chain = TREE_CHAIN (t);
12667 if (chain && chain != void_type_node)
12668 chain = RECUR (chain);
12669 if (purpose == TREE_PURPOSE (t)
12670 && value == TREE_VALUE (t)
12671 && chain == TREE_CHAIN (t))
12673 return tree_cons (purpose, value, chain);
12676 case COMPONENT_REF:
12682 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12683 args, complain, in_decl);
12684 /* Remember that there was a reference to this entity. */
12685 if (DECL_P (object))
12686 mark_used (object);
12687 object_type = TREE_TYPE (object);
12689 member = TREE_OPERAND (t, 1);
12690 if (BASELINK_P (member))
12691 member = tsubst_baselink (member,
12692 non_reference (TREE_TYPE (object)),
12693 args, complain, in_decl);
12695 member = tsubst_copy (member, args, complain, in_decl);
12696 if (member == error_mark_node)
12697 return error_mark_node;
12699 if (object_type && !CLASS_TYPE_P (object_type))
12701 if (SCALAR_TYPE_P (object_type))
12703 tree s = NULL_TREE;
12704 tree dtor = member;
12706 if (TREE_CODE (dtor) == SCOPE_REF)
12708 s = TREE_OPERAND (dtor, 0);
12709 dtor = TREE_OPERAND (dtor, 1);
12711 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12713 dtor = TREE_OPERAND (dtor, 0);
12715 return finish_pseudo_destructor_expr (object, s, dtor);
12719 else if (TREE_CODE (member) == SCOPE_REF
12720 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12725 /* Lookup the template functions now that we know what the
12727 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12728 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12729 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12730 /*is_type_p=*/false,
12731 /*complain=*/false);
12732 if (BASELINK_P (member))
12734 BASELINK_FUNCTIONS (member)
12735 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12737 member = (adjust_result_of_qualified_name_lookup
12738 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12743 qualified_name_lookup_error (object_type, tmpl, member,
12745 return error_mark_node;
12748 else if (TREE_CODE (member) == SCOPE_REF
12749 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12750 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12752 if (complain & tf_error)
12754 if (TYPE_P (TREE_OPERAND (member, 0)))
12755 error ("%qT is not a class or namespace",
12756 TREE_OPERAND (member, 0));
12758 error ("%qD is not a class or namespace",
12759 TREE_OPERAND (member, 0));
12761 return error_mark_node;
12763 else if (TREE_CODE (member) == FIELD_DECL)
12764 return finish_non_static_data_member (member, object, NULL_TREE);
12766 return finish_class_member_access_expr (object, member,
12767 /*template_p=*/false,
12773 (RECUR (TREE_OPERAND (t, 0)));
12777 VEC(constructor_elt,gc) *n;
12778 constructor_elt *ce;
12779 unsigned HOST_WIDE_INT idx;
12780 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12781 bool process_index_p;
12783 bool need_copy_p = false;
12786 if (type == error_mark_node)
12787 return error_mark_node;
12789 /* digest_init will do the wrong thing if we let it. */
12790 if (type && TYPE_PTRMEMFUNC_P (type))
12793 /* We do not want to process the index of aggregate
12794 initializers as they are identifier nodes which will be
12795 looked up by digest_init. */
12796 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12798 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12799 newlen = VEC_length (constructor_elt, n);
12800 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
12802 if (ce->index && process_index_p)
12803 ce->index = RECUR (ce->index);
12805 if (PACK_EXPANSION_P (ce->value))
12807 /* Substitute into the pack expansion. */
12808 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12811 if (ce->value == error_mark_node)
12813 else if (TREE_VEC_LENGTH (ce->value) == 1)
12814 /* Just move the argument into place. */
12815 ce->value = TREE_VEC_ELT (ce->value, 0);
12818 /* Update the length of the final CONSTRUCTOR
12819 arguments vector, and note that we will need to
12821 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12822 need_copy_p = true;
12826 ce->value = RECUR (ce->value);
12831 VEC(constructor_elt,gc) *old_n = n;
12833 n = VEC_alloc (constructor_elt, gc, newlen);
12834 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
12836 if (TREE_CODE (ce->value) == TREE_VEC)
12838 int i, len = TREE_VEC_LENGTH (ce->value);
12839 for (i = 0; i < len; ++i)
12840 CONSTRUCTOR_APPEND_ELT (n, 0,
12841 TREE_VEC_ELT (ce->value, i));
12844 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12848 r = build_constructor (init_list_type_node, n);
12849 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12851 if (TREE_HAS_CONSTRUCTOR (t))
12852 return finish_compound_literal (type, r);
12859 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12860 if (TYPE_P (operand_0))
12861 return get_typeid (operand_0);
12862 return build_typeid (operand_0);
12872 tree r = tsubst_copy (t, args, complain, in_decl);
12874 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12875 /* If the original type was a reference, we'll be wrapped in
12876 the appropriate INDIRECT_REF. */
12877 r = convert_from_reference (r);
12882 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12883 tsubst_copy (TREE_TYPE (t), args, complain,
12886 case OFFSETOF_EXPR:
12887 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12891 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12892 complain, in_decl);
12894 tree type2 = TRAIT_EXPR_TYPE2 (t);
12896 type2 = tsubst_copy (type2, args, complain, in_decl);
12898 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12903 tree old_stmt_expr = cur_stmt_expr;
12904 tree stmt_expr = begin_stmt_expr ();
12906 cur_stmt_expr = stmt_expr;
12907 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12908 integral_constant_expression_p);
12909 stmt_expr = finish_stmt_expr (stmt_expr, false);
12910 cur_stmt_expr = old_stmt_expr;
12912 /* If the resulting list of expression statement is empty,
12913 fold it further into void_zero_node. */
12914 if (empty_expr_stmt_p (stmt_expr))
12915 stmt_expr = void_zero_node;
12921 t = tsubst_copy (t, args, complain, in_decl);
12922 /* As in finish_id_expression, we resolve enumeration constants
12923 to their underlying values. */
12924 if (TREE_CODE (t) == CONST_DECL)
12926 used_types_insert (TREE_TYPE (t));
12927 return DECL_INITIAL (t);
12933 tree r = build_lambda_expr ();
12935 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12936 TREE_TYPE (r) = type;
12937 CLASSTYPE_LAMBDA_EXPR (type) = r;
12939 LAMBDA_EXPR_LOCATION (r)
12940 = LAMBDA_EXPR_LOCATION (t);
12941 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12942 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12943 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12944 LAMBDA_EXPR_DISCRIMINATOR (r)
12945 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12946 LAMBDA_EXPR_CAPTURE_LIST (r)
12947 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12948 LAMBDA_EXPR_THIS_CAPTURE (r)
12949 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12950 LAMBDA_EXPR_EXTRA_SCOPE (r)
12951 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12953 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12954 determine_visibility (TYPE_NAME (type));
12955 /* Now that we know visibility, instantiate the type so we have a
12956 declaration of the op() for later calls to lambda_function. */
12957 complete_type (type);
12959 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12961 apply_lambda_return_type (r, type);
12963 return build_lambda_object (r);
12967 /* Handle Objective-C++ constructs, if appropriate. */
12970 = objcp_tsubst_copy_and_build (t, args, complain,
12971 in_decl, /*function_p=*/false);
12975 return tsubst_copy (t, args, complain, in_decl);
12981 /* Verify that the instantiated ARGS are valid. For type arguments,
12982 make sure that the type's linkage is ok. For non-type arguments,
12983 make sure they are constants if they are integral or enumerations.
12984 Emit an error under control of COMPLAIN, and return TRUE on error. */
12987 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12989 if (ARGUMENT_PACK_P (t))
12991 tree vec = ARGUMENT_PACK_ARGS (t);
12992 int len = TREE_VEC_LENGTH (vec);
12993 bool result = false;
12996 for (i = 0; i < len; ++i)
12997 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13001 else if (TYPE_P (t))
13003 /* [basic.link]: A name with no linkage (notably, the name
13004 of a class or enumeration declared in a local scope)
13005 shall not be used to declare an entity with linkage.
13006 This implies that names with no linkage cannot be used as
13009 DR 757 relaxes this restriction for C++0x. */
13010 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13011 : no_linkage_check (t, /*relaxed_p=*/false));
13015 /* DR 488 makes use of a type with no linkage cause
13016 type deduction to fail. */
13017 if (complain & tf_error)
13019 if (TYPE_ANONYMOUS_P (nt))
13020 error ("%qT is/uses anonymous type", t);
13022 error ("template argument for %qD uses local type %qT",
13027 /* In order to avoid all sorts of complications, we do not
13028 allow variably-modified types as template arguments. */
13029 else if (variably_modified_type_p (t, NULL_TREE))
13031 if (complain & tf_error)
13032 error ("%qT is a variably modified type", t);
13036 /* A non-type argument of integral or enumerated type must be a
13038 else if (TREE_TYPE (t)
13039 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13040 && !TREE_CONSTANT (t))
13042 if (complain & tf_error)
13043 error ("integral expression %qE is not constant", t);
13050 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13052 int ix, len = DECL_NTPARMS (tmpl);
13053 bool result = false;
13055 for (ix = 0; ix != len; ix++)
13057 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13060 if (result && (complain & tf_error))
13061 error (" trying to instantiate %qD", tmpl);
13065 /* Instantiate the indicated variable or function template TMPL with
13066 the template arguments in TARG_PTR. */
13069 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13071 tree targ_ptr = orig_args;
13075 HOST_WIDE_INT saved_processing_template_decl;
13077 if (tmpl == error_mark_node)
13078 return error_mark_node;
13080 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13082 /* If this function is a clone, handle it specially. */
13083 if (DECL_CLONED_FUNCTION_P (tmpl))
13088 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13089 DECL_CLONED_FUNCTION. */
13090 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13091 targ_ptr, complain);
13092 if (spec == error_mark_node)
13093 return error_mark_node;
13095 /* Look for the clone. */
13096 FOR_EACH_CLONE (clone, spec)
13097 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13099 /* We should always have found the clone by now. */
13100 gcc_unreachable ();
13104 /* Check to see if we already have this specialization. */
13105 gen_tmpl = most_general_template (tmpl);
13106 if (tmpl != gen_tmpl)
13107 /* The TMPL is a partial instantiation. To get a full set of
13108 arguments we must add the arguments used to perform the
13109 partial instantiation. */
13110 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13113 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13114 but it doesn't seem to be on the hot path. */
13115 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13117 gcc_assert (tmpl == gen_tmpl
13118 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13120 || fndecl == NULL_TREE);
13122 if (spec != NULL_TREE)
13125 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13127 return error_mark_node;
13129 /* We are building a FUNCTION_DECL, during which the access of its
13130 parameters and return types have to be checked. However this
13131 FUNCTION_DECL which is the desired context for access checking
13132 is not built yet. We solve this chicken-and-egg problem by
13133 deferring all checks until we have the FUNCTION_DECL. */
13134 push_deferring_access_checks (dk_deferred);
13136 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13137 (because, for example, we have encountered a non-dependent
13138 function call in the body of a template function and must now
13139 determine which of several overloaded functions will be called),
13140 within the instantiation itself we are not processing a
13142 saved_processing_template_decl = processing_template_decl;
13143 processing_template_decl = 0;
13144 /* Substitute template parameters to obtain the specialization. */
13145 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13146 targ_ptr, complain, gen_tmpl);
13147 processing_template_decl = saved_processing_template_decl;
13148 if (fndecl == error_mark_node)
13149 return error_mark_node;
13151 /* Now we know the specialization, compute access previously
13153 push_access_scope (fndecl);
13155 /* Some typedefs referenced from within the template code need to be access
13156 checked at template instantiation time, i.e now. These types were
13157 added to the template at parsing time. Let's get those and perfom
13158 the acces checks then. */
13159 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13160 perform_deferred_access_checks ();
13161 pop_access_scope (fndecl);
13162 pop_deferring_access_checks ();
13164 /* The DECL_TI_TEMPLATE should always be the immediate parent
13165 template, not the most general template. */
13166 DECL_TI_TEMPLATE (fndecl) = tmpl;
13168 /* If we've just instantiated the main entry point for a function,
13169 instantiate all the alternate entry points as well. We do this
13170 by cloning the instantiation of the main entry point, not by
13171 instantiating the template clones. */
13172 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13173 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13178 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13179 NARGS elements of the arguments that are being used when calling
13180 it. TARGS is a vector into which the deduced template arguments
13183 Return zero for success, 2 for an incomplete match that doesn't resolve
13184 all the types, and 1 for complete failure. An error message will be
13185 printed only for an incomplete match.
13187 If FN is a conversion operator, or we are trying to produce a specific
13188 specialization, RETURN_TYPE is the return type desired.
13190 The EXPLICIT_TARGS are explicit template arguments provided via a
13193 The parameter STRICT is one of:
13196 We are deducing arguments for a function call, as in
13197 [temp.deduct.call].
13200 We are deducing arguments for a conversion function, as in
13201 [temp.deduct.conv].
13204 We are deducing arguments when doing an explicit instantiation
13205 as in [temp.explicit], when determining an explicit specialization
13206 as in [temp.expl.spec], or when taking the address of a function
13207 template, as in [temp.deduct.funcaddr]. */
13210 fn_type_unification (tree fn,
13211 tree explicit_targs,
13214 unsigned int nargs,
13216 unification_kind_t strict,
13222 bool incomplete_argument_packs_p = false;
13224 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13226 fntype = TREE_TYPE (fn);
13227 if (explicit_targs)
13231 The specified template arguments must match the template
13232 parameters in kind (i.e., type, nontype, template), and there
13233 must not be more arguments than there are parameters;
13234 otherwise type deduction fails.
13236 Nontype arguments must match the types of the corresponding
13237 nontype template parameters, or must be convertible to the
13238 types of the corresponding nontype parameters as specified in
13239 _temp.arg.nontype_, otherwise type deduction fails.
13241 All references in the function type of the function template
13242 to the corresponding template parameters are replaced by the
13243 specified template argument values. If a substitution in a
13244 template parameter or in the function type of the function
13245 template results in an invalid type, type deduction fails. */
13246 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13247 int i, len = TREE_VEC_LENGTH (tparms);
13248 tree converted_args;
13249 bool incomplete = false;
13251 if (explicit_targs == error_mark_node)
13255 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13256 /*require_all_args=*/false,
13257 /*use_default_args=*/false));
13258 if (converted_args == error_mark_node)
13261 /* Substitute the explicit args into the function type. This is
13262 necessary so that, for instance, explicitly declared function
13263 arguments can match null pointed constants. If we were given
13264 an incomplete set of explicit args, we must not do semantic
13265 processing during substitution as we could create partial
13267 for (i = 0; i < len; i++)
13269 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13270 bool parameter_pack = false;
13272 /* Dig out the actual parm. */
13273 if (TREE_CODE (parm) == TYPE_DECL
13274 || TREE_CODE (parm) == TEMPLATE_DECL)
13276 parm = TREE_TYPE (parm);
13277 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13279 else if (TREE_CODE (parm) == PARM_DECL)
13281 parm = DECL_INITIAL (parm);
13282 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13285 if (parameter_pack)
13289 template_parm_level_and_index (parm, &level, &idx);
13291 /* Mark the argument pack as "incomplete". We could
13292 still deduce more arguments during unification. */
13293 targ = TMPL_ARG (converted_args, level, idx);
13296 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13297 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13298 = ARGUMENT_PACK_ARGS (targ);
13301 /* We have some incomplete argument packs. */
13302 incomplete_argument_packs_p = true;
13306 if (incomplete_argument_packs_p)
13307 /* Any substitution is guaranteed to be incomplete if there
13308 are incomplete argument packs, because we can still deduce
13312 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13314 processing_template_decl += incomplete;
13315 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
13316 processing_template_decl -= incomplete;
13318 if (fntype == error_mark_node)
13321 /* Place the explicitly specified arguments in TARGS. */
13322 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13323 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13326 /* Never do unification on the 'this' parameter. */
13327 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13333 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13334 new_args = XALLOCAVEC (tree, nargs + 1);
13335 new_args[0] = return_type;
13336 memcpy (new_args + 1, args, nargs * sizeof (tree));
13341 /* We allow incomplete unification without an error message here
13342 because the standard doesn't seem to explicitly prohibit it. Our
13343 callers must be ready to deal with unification failures in any
13345 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13346 targs, parms, args, nargs, /*subr=*/0,
13349 if (result == 0 && incomplete_argument_packs_p)
13351 int i, len = NUM_TMPL_ARGS (targs);
13353 /* Clear the "incomplete" flags on all argument packs. */
13354 for (i = 0; i < len; i++)
13356 tree arg = TREE_VEC_ELT (targs, i);
13357 if (ARGUMENT_PACK_P (arg))
13359 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
13360 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
13365 /* Now that we have bindings for all of the template arguments,
13366 ensure that the arguments deduced for the template template
13367 parameters have compatible template parameter lists. We cannot
13368 check this property before we have deduced all template
13369 arguments, because the template parameter types of a template
13370 template parameter might depend on prior template parameters
13371 deduced after the template template parameter. The following
13372 ill-formed example illustrates this issue:
13374 template<typename T, template<T> class C> void f(C<5>, T);
13376 template<int N> struct X {};
13379 f(X<5>(), 5l); // error: template argument deduction fails
13382 The template parameter list of 'C' depends on the template type
13383 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13384 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13385 time that we deduce 'C'. */
13387 && !template_template_parm_bindings_ok_p
13388 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
13392 /* All is well so far. Now, check:
13396 When all template arguments have been deduced, all uses of
13397 template parameters in nondeduced contexts are replaced with
13398 the corresponding deduced argument values. If the
13399 substitution results in an invalid type, as described above,
13400 type deduction fails. */
13402 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
13403 if (substed == error_mark_node)
13406 /* If we're looking for an exact match, check that what we got
13407 is indeed an exact match. It might not be if some template
13408 parameters are used in non-deduced contexts. */
13409 if (strict == DEDUCE_EXACT)
13414 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
13416 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
13417 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
13418 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13426 /* Adjust types before performing type deduction, as described in
13427 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
13428 sections are symmetric. PARM is the type of a function parameter
13429 or the return type of the conversion function. ARG is the type of
13430 the argument passed to the call, or the type of the value
13431 initialized with the result of the conversion function.
13432 ARG_EXPR is the original argument expression, which may be null. */
13435 maybe_adjust_types_for_deduction (unification_kind_t strict,
13449 /* Swap PARM and ARG throughout the remainder of this
13450 function; the handling is precisely symmetric since PARM
13451 will initialize ARG rather than vice versa. */
13459 /* Core issue #873: Do the DR606 thing (see below) for these cases,
13460 too, but here handle it by stripping the reference from PARM
13461 rather than by adding it to ARG. */
13462 if (TREE_CODE (*parm) == REFERENCE_TYPE
13463 && TYPE_REF_IS_RVALUE (*parm)
13464 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13465 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13466 && TREE_CODE (*arg) == REFERENCE_TYPE
13467 && !TYPE_REF_IS_RVALUE (*arg))
13468 *parm = TREE_TYPE (*parm);
13469 /* Nothing else to do in this case. */
13473 gcc_unreachable ();
13476 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13478 /* [temp.deduct.call]
13480 If P is not a reference type:
13482 --If A is an array type, the pointer type produced by the
13483 array-to-pointer standard conversion (_conv.array_) is
13484 used in place of A for type deduction; otherwise,
13486 --If A is a function type, the pointer type produced by
13487 the function-to-pointer standard conversion
13488 (_conv.func_) is used in place of A for type deduction;
13491 --If A is a cv-qualified type, the top level
13492 cv-qualifiers of A's type are ignored for type
13494 if (TREE_CODE (*arg) == ARRAY_TYPE)
13495 *arg = build_pointer_type (TREE_TYPE (*arg));
13496 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13497 *arg = build_pointer_type (*arg);
13499 *arg = TYPE_MAIN_VARIANT (*arg);
13502 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13503 of the form T&&, where T is a template parameter, and the argument
13504 is an lvalue, T is deduced as A& */
13505 if (TREE_CODE (*parm) == REFERENCE_TYPE
13506 && TYPE_REF_IS_RVALUE (*parm)
13507 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13508 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13509 && arg_expr && real_lvalue_p (arg_expr))
13510 *arg = build_reference_type (*arg);
13512 /* [temp.deduct.call]
13514 If P is a cv-qualified type, the top level cv-qualifiers
13515 of P's type are ignored for type deduction. If P is a
13516 reference type, the type referred to by P is used for
13518 *parm = TYPE_MAIN_VARIANT (*parm);
13519 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13521 *parm = TREE_TYPE (*parm);
13522 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13525 /* DR 322. For conversion deduction, remove a reference type on parm
13526 too (which has been swapped into ARG). */
13527 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13528 *arg = TREE_TYPE (*arg);
13533 /* Most parms like fn_type_unification.
13535 If SUBR is 1, we're being called recursively (to unify the
13536 arguments of a function or method parameter of a function
13540 type_unification_real (tree tparms,
13544 unsigned int xnargs,
13546 unification_kind_t strict,
13549 tree parm, arg, arg_expr;
13551 int ntparms = TREE_VEC_LENGTH (tparms);
13553 int saw_undeduced = 0;
13556 unsigned int nargs;
13559 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13560 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13561 gcc_assert (ntparms > 0);
13563 /* Reset the number of non-defaulted template arguments contained
13565 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
13570 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13571 | UNIFY_ALLOW_DERIVED);
13575 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13579 sub_strict = UNIFY_ALLOW_NONE;
13583 gcc_unreachable ();
13592 while (parms && parms != void_list_node
13595 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13598 parm = TREE_VALUE (parms);
13599 parms = TREE_CHAIN (parms);
13604 if (arg == error_mark_node)
13606 if (arg == unknown_type_node)
13607 /* We can't deduce anything from this, but we might get all the
13608 template args from other function args. */
13611 /* Conversions will be performed on a function argument that
13612 corresponds with a function parameter that contains only
13613 non-deducible template parameters and explicitly specified
13614 template parameters. */
13615 if (!uses_template_parms (parm))
13620 type = TREE_TYPE (arg);
13624 if (same_type_p (parm, type))
13626 if (strict != DEDUCE_EXACT
13627 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13636 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13637 if (type_unknown_p (arg))
13639 /* [temp.deduct.type]
13641 A template-argument can be deduced from a pointer to
13642 function or pointer to member function argument if
13643 the set of overloaded functions does not contain
13644 function templates and at most one of a set of
13645 overloaded functions provides a unique match. */
13646 if (resolve_overloaded_unification
13647 (tparms, targs, parm, arg, strict, sub_strict))
13653 arg = unlowered_expr_type (arg);
13654 if (arg == error_mark_node)
13659 int arg_strict = sub_strict;
13662 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13665 if (arg == init_list_type_node && arg_expr)
13667 if (unify (tparms, targs, parm, arg, arg_strict))
13674 && parms != void_list_node
13675 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13677 /* Unify the remaining arguments with the pack expansion type. */
13679 tree parmvec = make_tree_vec (1);
13681 /* Allocate a TREE_VEC and copy in all of the arguments */
13682 argvec = make_tree_vec (nargs - ia);
13683 for (i = 0; ia < nargs; ++ia, ++i)
13684 TREE_VEC_ELT (argvec, i) = args[ia];
13686 /* Copy the parameter into parmvec. */
13687 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13688 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13689 /*call_args_p=*/true, /*subr=*/subr))
13692 /* Advance to the end of the list of parameters. */
13693 parms = TREE_CHAIN (parms);
13696 /* Fail if we've reached the end of the parm list, and more args
13697 are present, and the parm list isn't variadic. */
13698 if (ia < nargs && parms == void_list_node)
13700 /* Fail if parms are left and they don't have default values. */
13701 if (parms && parms != void_list_node
13702 && TREE_PURPOSE (parms) == NULL_TREE)
13706 for (i = 0; i < ntparms; i++)
13707 if (!TREE_VEC_ELT (targs, i))
13711 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13714 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13716 /* If this is an undeduced nontype parameter that depends on
13717 a type parameter, try another pass; its type may have been
13718 deduced from a later argument than the one from which
13719 this parameter can be deduced. */
13720 if (TREE_CODE (tparm) == PARM_DECL
13721 && uses_template_parms (TREE_TYPE (tparm))
13722 && !saw_undeduced++)
13725 /* Core issue #226 (C++0x) [temp.deduct]:
13727 If a template argument has not been deduced, its
13728 default template argument, if any, is used.
13730 When we are in C++98 mode, TREE_PURPOSE will either
13731 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13732 to explicitly check cxx_dialect here. */
13733 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13735 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13736 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13737 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13738 arg = convert_template_argument (parm, arg, targs, tf_none,
13740 if (arg == error_mark_node)
13744 TREE_VEC_ELT (targs, i) = arg;
13745 /* The position of the first default template argument,
13746 is also the number of non-defaulted arguments in TARGS.
13748 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13749 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
13754 /* If the type parameter is a parameter pack, then it will
13755 be deduced to an empty parameter pack. */
13756 if (template_parameter_pack_p (tparm))
13760 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13762 arg = make_node (NONTYPE_ARGUMENT_PACK);
13763 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13764 TREE_CONSTANT (arg) = 1;
13767 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13769 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13771 TREE_VEC_ELT (targs, i) = arg;
13777 #ifdef ENABLE_CHECKING
13778 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13779 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
13785 /* Subroutine of type_unification_real. Args are like the variables
13786 at the call site. ARG is an overloaded function (or template-id);
13787 we try deducing template args from each of the overloads, and if
13788 only one succeeds, we go with that. Modifies TARGS and returns
13789 true on success. */
13792 resolve_overloaded_unification (tree tparms,
13796 unification_kind_t strict,
13799 tree tempargs = copy_node (targs);
13801 tree goodfn = NULL_TREE;
13804 if (TREE_CODE (arg) == ADDR_EXPR)
13806 arg = TREE_OPERAND (arg, 0);
13812 if (TREE_CODE (arg) == COMPONENT_REF)
13813 /* Handle `&x' where `x' is some static or non-static member
13815 arg = TREE_OPERAND (arg, 1);
13817 if (TREE_CODE (arg) == OFFSET_REF)
13818 arg = TREE_OPERAND (arg, 1);
13820 /* Strip baselink information. */
13821 if (BASELINK_P (arg))
13822 arg = BASELINK_FUNCTIONS (arg);
13824 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13826 /* If we got some explicit template args, we need to plug them into
13827 the affected templates before we try to unify, in case the
13828 explicit args will completely resolve the templates in question. */
13830 tree expl_subargs = TREE_OPERAND (arg, 1);
13831 arg = TREE_OPERAND (arg, 0);
13833 for (; arg; arg = OVL_NEXT (arg))
13835 tree fn = OVL_CURRENT (arg);
13836 tree subargs, elem;
13838 if (TREE_CODE (fn) != TEMPLATE_DECL)
13841 ++processing_template_decl;
13842 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13843 expl_subargs, /*check_ret=*/false);
13846 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13847 if (try_one_overload (tparms, targs, tempargs, parm,
13848 elem, strict, sub_strict, addr_p)
13849 && (!goodfn || !decls_match (goodfn, elem)))
13855 --processing_template_decl;
13858 else if (TREE_CODE (arg) != OVERLOAD
13859 && TREE_CODE (arg) != FUNCTION_DECL)
13860 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13861 -- but the deduction does not succeed because the expression is
13862 not just the function on its own. */
13865 for (; arg; arg = OVL_NEXT (arg))
13866 if (try_one_overload (tparms, targs, tempargs, parm,
13867 TREE_TYPE (OVL_CURRENT (arg)),
13868 strict, sub_strict, addr_p)
13869 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13871 goodfn = OVL_CURRENT (arg);
13875 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13876 to function or pointer to member function argument if the set of
13877 overloaded functions does not contain function templates and at most
13878 one of a set of overloaded functions provides a unique match.
13880 So if we found multiple possibilities, we return success but don't
13881 deduce anything. */
13885 int i = TREE_VEC_LENGTH (targs);
13887 if (TREE_VEC_ELT (tempargs, i))
13888 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13896 /* Core DR 115: In contexts where deduction is done and fails, or in
13897 contexts where deduction is not done, if a template argument list is
13898 specified and it, along with any default template arguments, identifies
13899 a single function template specialization, then the template-id is an
13900 lvalue for the function template specialization. */
13903 resolve_nondeduced_context (tree orig_expr)
13905 tree expr, offset, baselink;
13908 if (!type_unknown_p (orig_expr))
13913 offset = NULL_TREE;
13914 baselink = NULL_TREE;
13916 if (TREE_CODE (expr) == ADDR_EXPR)
13918 expr = TREE_OPERAND (expr, 0);
13921 if (TREE_CODE (expr) == OFFSET_REF)
13924 expr = TREE_OPERAND (expr, 1);
13926 if (TREE_CODE (expr) == BASELINK)
13929 expr = BASELINK_FUNCTIONS (expr);
13932 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13935 tree goodfn = NULL_TREE;
13937 /* If we got some explicit template args, we need to plug them into
13938 the affected templates before we try to unify, in case the
13939 explicit args will completely resolve the templates in question. */
13941 tree expl_subargs = TREE_OPERAND (expr, 1);
13942 tree arg = TREE_OPERAND (expr, 0);
13943 tree badfn = NULL_TREE;
13944 tree badargs = NULL_TREE;
13946 for (; arg; arg = OVL_NEXT (arg))
13948 tree fn = OVL_CURRENT (arg);
13949 tree subargs, elem;
13951 if (TREE_CODE (fn) != TEMPLATE_DECL)
13954 ++processing_template_decl;
13955 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13956 expl_subargs, /*check_ret=*/false);
13957 if (subargs && !any_dependent_template_arguments_p (subargs))
13959 elem = instantiate_template (fn, subargs, tf_none);
13960 if (elem == error_mark_node)
13965 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13971 --processing_template_decl;
13977 expr = build_baselink (BASELINK_BINFO (baselink),
13978 BASELINK_ACCESS_BINFO (baselink),
13979 expr, BASELINK_OPTYPE (baselink));
13981 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13982 TREE_OPERAND (offset, 0), expr);
13984 expr = build_address (expr);
13987 else if (good == 0 && badargs)
13988 /* There were no good options and at least one bad one, so let the
13989 user know what the problem is. */
13990 instantiate_template (badfn, badargs, tf_warning_or_error);
13995 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13996 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13997 different overloads deduce different arguments for a given parm.
13998 ADDR_P is true if the expression for which deduction is being
13999 performed was of the form "& fn" rather than simply "fn".
14001 Returns 1 on success. */
14004 try_one_overload (tree tparms,
14009 unification_kind_t strict,
14017 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14018 to function or pointer to member function argument if the set of
14019 overloaded functions does not contain function templates and at most
14020 one of a set of overloaded functions provides a unique match.
14022 So if this is a template, just return success. */
14024 if (uses_template_parms (arg))
14027 if (TREE_CODE (arg) == METHOD_TYPE)
14028 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14030 arg = build_pointer_type (arg);
14032 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14034 /* We don't copy orig_targs for this because if we have already deduced
14035 some template args from previous args, unify would complain when we
14036 try to deduce a template parameter for the same argument, even though
14037 there isn't really a conflict. */
14038 nargs = TREE_VEC_LENGTH (targs);
14039 tempargs = make_tree_vec (nargs);
14041 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14044 /* First make sure we didn't deduce anything that conflicts with
14045 explicitly specified args. */
14046 for (i = nargs; i--; )
14048 tree elt = TREE_VEC_ELT (tempargs, i);
14049 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14053 else if (uses_template_parms (elt))
14054 /* Since we're unifying against ourselves, we will fill in
14055 template args used in the function parm list with our own
14056 template parms. Discard them. */
14057 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14058 else if (oldelt && !template_args_equal (oldelt, elt))
14062 for (i = nargs; i--; )
14064 tree elt = TREE_VEC_ELT (tempargs, i);
14067 TREE_VEC_ELT (targs, i) = elt;
14073 /* PARM is a template class (perhaps with unbound template
14074 parameters). ARG is a fully instantiated type. If ARG can be
14075 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14076 TARGS are as for unify. */
14079 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14081 tree copy_of_targs;
14083 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14084 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14085 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14088 /* We need to make a new template argument vector for the call to
14089 unify. If we used TARGS, we'd clutter it up with the result of
14090 the attempted unification, even if this class didn't work out.
14091 We also don't want to commit ourselves to all the unifications
14092 we've already done, since unification is supposed to be done on
14093 an argument-by-argument basis. In other words, consider the
14094 following pathological case:
14096 template <int I, int J, int K>
14099 template <int I, int J>
14100 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14102 template <int I, int J, int K>
14103 void f(S<I, J, K>, S<I, I, I>);
14112 Now, by the time we consider the unification involving `s2', we
14113 already know that we must have `f<0, 0, 0>'. But, even though
14114 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14115 because there are two ways to unify base classes of S<0, 1, 2>
14116 with S<I, I, I>. If we kept the already deduced knowledge, we
14117 would reject the possibility I=1. */
14118 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14120 /* If unification failed, we're done. */
14121 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14122 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14128 /* Given a template type PARM and a class type ARG, find the unique
14129 base type in ARG that is an instance of PARM. We do not examine
14130 ARG itself; only its base-classes. If there is not exactly one
14131 appropriate base class, return NULL_TREE. PARM may be the type of
14132 a partial specialization, as well as a plain template type. Used
14136 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14138 tree rval = NULL_TREE;
14141 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14143 binfo = TYPE_BINFO (complete_type (arg));
14145 /* The type could not be completed. */
14148 /* Walk in inheritance graph order. The search order is not
14149 important, and this avoids multiple walks of virtual bases. */
14150 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14152 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14156 /* If there is more than one satisfactory baseclass, then:
14160 If they yield more than one possible deduced A, the type
14164 if (rval && !same_type_p (r, rval))
14174 /* Returns the level of DECL, which declares a template parameter. */
14177 template_decl_level (tree decl)
14179 switch (TREE_CODE (decl))
14182 case TEMPLATE_DECL:
14183 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14186 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14189 gcc_unreachable ();
14194 /* Decide whether ARG can be unified with PARM, considering only the
14195 cv-qualifiers of each type, given STRICT as documented for unify.
14196 Returns nonzero iff the unification is OK on that basis. */
14199 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14201 int arg_quals = cp_type_quals (arg);
14202 int parm_quals = cp_type_quals (parm);
14204 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14205 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14207 /* Although a CVR qualifier is ignored when being applied to a
14208 substituted template parameter ([8.3.2]/1 for example), that
14209 does not allow us to unify "const T" with "int&" because both
14210 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14211 It is ok when we're allowing additional CV qualifiers
14212 at the outer level [14.8.2.1]/3,1st bullet. */
14213 if ((TREE_CODE (arg) == REFERENCE_TYPE
14214 || TREE_CODE (arg) == FUNCTION_TYPE
14215 || TREE_CODE (arg) == METHOD_TYPE)
14216 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14219 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14220 && (parm_quals & TYPE_QUAL_RESTRICT))
14224 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14225 && (arg_quals & parm_quals) != parm_quals)
14228 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14229 && (parm_quals & arg_quals) != arg_quals)
14235 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14237 template_parm_level_and_index (tree parm, int* level, int* index)
14239 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14240 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14241 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14243 *index = TEMPLATE_TYPE_IDX (parm);
14244 *level = TEMPLATE_TYPE_LEVEL (parm);
14248 *index = TEMPLATE_PARM_IDX (parm);
14249 *level = TEMPLATE_PARM_LEVEL (parm);
14253 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14254 expansion at the end of PACKED_PARMS. Returns 0 if the type
14255 deduction succeeds, 1 otherwise. STRICT is the same as in
14256 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14257 call argument list. We'll need to adjust the arguments to make them
14258 types. SUBR tells us if this is from a recursive call to
14259 type_unification_real. */
14261 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14262 tree packed_args, int strict, bool call_args_p,
14266 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14267 tree pattern = PACK_EXPANSION_PATTERN (parm);
14268 tree pack, packs = NULL_TREE;
14269 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14270 int len = TREE_VEC_LENGTH (packed_args);
14272 /* Determine the parameter packs we will be deducing from the
14273 pattern, and record their current deductions. */
14274 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14275 pack; pack = TREE_CHAIN (pack))
14277 tree parm_pack = TREE_VALUE (pack);
14280 /* Determine the index and level of this parameter pack. */
14281 template_parm_level_and_index (parm_pack, &level, &idx);
14283 /* Keep track of the parameter packs and their corresponding
14285 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14286 TREE_TYPE (packs) = make_tree_vec (len - start);
14289 /* Loop through all of the arguments that have not yet been
14290 unified and unify each with the pattern. */
14291 for (i = start; i < len; i++)
14293 tree parm = pattern;
14295 /* For each parameter pack, clear out the deduced value so that
14296 we can deduce it again. */
14297 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14300 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14302 TMPL_ARG (targs, level, idx) = NULL_TREE;
14305 /* Unify the pattern with the current argument. */
14307 tree arg = TREE_VEC_ELT (packed_args, i);
14308 tree arg_expr = NULL_TREE;
14309 int arg_strict = strict;
14310 bool skip_arg_p = false;
14316 /* This mirrors what we do in type_unification_real. */
14320 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14321 | UNIFY_ALLOW_MORE_CV_QUAL
14322 | UNIFY_ALLOW_DERIVED);
14326 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14330 sub_strict = UNIFY_ALLOW_NONE;
14334 gcc_unreachable ();
14339 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14340 if (type_unknown_p (arg))
14342 /* [temp.deduct.type] A template-argument can be
14343 deduced from a pointer to function or pointer
14344 to member function argument if the set of
14345 overloaded functions does not contain function
14346 templates and at most one of a set of
14347 overloaded functions provides a unique
14350 if (resolve_overloaded_unification
14351 (tparms, targs, parm, arg,
14352 (unification_kind_t) strict,
14362 arg = unlowered_expr_type (arg);
14363 if (arg == error_mark_node)
14368 arg_strict = sub_strict;
14372 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
14373 &parm, &arg, arg_expr);
14378 /* For deduction from an init-list we need the actual list. */
14379 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14381 if (unify (tparms, targs, parm, arg, arg_strict))
14386 /* For each parameter pack, collect the deduced value. */
14387 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14390 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14392 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
14393 TMPL_ARG (targs, level, idx);
14397 /* Verify that the results of unification with the parameter packs
14398 produce results consistent with what we've seen before, and make
14399 the deduced argument packs available. */
14400 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14402 tree old_pack = TREE_VALUE (pack);
14403 tree new_args = TREE_TYPE (pack);
14404 int i, len = TREE_VEC_LENGTH (new_args);
14406 bool nondeduced_p = false;
14408 /* By default keep the original deduced argument pack.
14409 If necessary, more specific code is going to update the
14410 resulting deduced argument later down in this function. */
14411 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14412 TMPL_ARG (targs, level, idx) = old_pack;
14414 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
14415 actually deduce anything. */
14416 for (i = 0; i < len && !nondeduced_p; ++i)
14417 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
14418 nondeduced_p = true;
14422 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
14424 /* Prepend the explicit arguments onto NEW_ARGS. */
14425 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14426 tree old_args = new_args;
14427 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
14428 int len = explicit_len + TREE_VEC_LENGTH (old_args);
14430 /* Copy the explicit arguments. */
14431 new_args = make_tree_vec (len);
14432 for (i = 0; i < explicit_len; i++)
14433 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
14435 /* Copy the deduced arguments. */
14436 for (; i < len; i++)
14437 TREE_VEC_ELT (new_args, i) =
14438 TREE_VEC_ELT (old_args, i - explicit_len);
14444 /* Build the deduced *_ARGUMENT_PACK. */
14445 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
14447 result = make_node (NONTYPE_ARGUMENT_PACK);
14448 TREE_TYPE (result) =
14449 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
14450 TREE_CONSTANT (result) = 1;
14453 result = cxx_make_type (TYPE_ARGUMENT_PACK);
14455 SET_ARGUMENT_PACK_ARGS (result, new_args);
14457 /* Note the deduced argument packs for this parameter
14459 TMPL_ARG (targs, level, idx) = result;
14461 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
14462 && (ARGUMENT_PACK_ARGS (old_pack)
14463 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
14465 /* We only had the explicitly-provided arguments before, but
14466 now we have a complete set of arguments. */
14467 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14469 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
14470 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
14471 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
14473 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
14475 /* Inconsistent unification of this parameter pack. */
14482 /* Deduce the value of template parameters. TPARMS is the (innermost)
14483 set of template parameters to a template. TARGS is the bindings
14484 for those template parameters, as determined thus far; TARGS may
14485 include template arguments for outer levels of template parameters
14486 as well. PARM is a parameter to a template function, or a
14487 subcomponent of that parameter; ARG is the corresponding argument.
14488 This function attempts to match PARM with ARG in a manner
14489 consistent with the existing assignments in TARGS. If more values
14490 are deduced, then TARGS is updated.
14492 Returns 0 if the type deduction succeeds, 1 otherwise. The
14493 parameter STRICT is a bitwise or of the following flags:
14496 Require an exact match between PARM and ARG.
14497 UNIFY_ALLOW_MORE_CV_QUAL:
14498 Allow the deduced ARG to be more cv-qualified (by qualification
14499 conversion) than ARG.
14500 UNIFY_ALLOW_LESS_CV_QUAL:
14501 Allow the deduced ARG to be less cv-qualified than ARG.
14502 UNIFY_ALLOW_DERIVED:
14503 Allow the deduced ARG to be a template base class of ARG,
14504 or a pointer to a template base class of the type pointed to by
14506 UNIFY_ALLOW_INTEGER:
14507 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14508 case for more information.
14509 UNIFY_ALLOW_OUTER_LEVEL:
14510 This is the outermost level of a deduction. Used to determine validity
14511 of qualification conversions. A valid qualification conversion must
14512 have const qualified pointers leading up to the inner type which
14513 requires additional CV quals, except at the outer level, where const
14514 is not required [conv.qual]. It would be normal to set this flag in
14515 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14516 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14517 This is the outermost level of a deduction, and PARM can be more CV
14518 qualified at this point.
14519 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14520 This is the outermost level of a deduction, and PARM can be less CV
14521 qualified at this point. */
14524 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14529 int strict_in = strict;
14531 /* I don't think this will do the right thing with respect to types.
14532 But the only case I've seen it in so far has been array bounds, where
14533 signedness is the only information lost, and I think that will be
14535 while (TREE_CODE (parm) == NOP_EXPR)
14536 parm = TREE_OPERAND (parm, 0);
14538 if (arg == error_mark_node)
14540 if (arg == unknown_type_node
14541 || arg == init_list_type_node)
14542 /* We can't deduce anything from this, but we might get all the
14543 template args from other function args. */
14546 /* If PARM uses template parameters, then we can't bail out here,
14547 even if ARG == PARM, since we won't record unifications for the
14548 template parameters. We might need them if we're trying to
14549 figure out which of two things is more specialized. */
14550 if (arg == parm && !uses_template_parms (parm))
14553 /* Handle init lists early, so the rest of the function can assume
14554 we're dealing with a type. */
14555 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14559 tree orig_parm = parm;
14561 /* Replace T with std::initializer_list<T> for deduction. */
14562 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14563 && flag_deduce_init_list)
14564 parm = listify (parm);
14566 if (!is_std_init_list (parm))
14567 /* We can only deduce from an initializer list argument if the
14568 parameter is std::initializer_list; otherwise this is a
14569 non-deduced context. */
14572 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14574 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14576 int elt_strict = strict;
14578 if (elt == error_mark_node)
14581 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14583 tree type = TREE_TYPE (elt);
14584 /* It should only be possible to get here for a call. */
14585 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14586 elt_strict |= maybe_adjust_types_for_deduction
14587 (DEDUCE_CALL, &elttype, &type, elt);
14591 if (unify (tparms, targs, elttype, elt, elt_strict))
14595 /* If the std::initializer_list<T> deduction worked, replace the
14596 deduced A with std::initializer_list<A>. */
14597 if (orig_parm != parm)
14599 idx = TEMPLATE_TYPE_IDX (orig_parm);
14600 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14601 targ = listify (targ);
14602 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14607 /* Immediately reject some pairs that won't unify because of
14608 cv-qualification mismatches. */
14609 if (TREE_CODE (arg) == TREE_CODE (parm)
14611 /* It is the elements of the array which hold the cv quals of an array
14612 type, and the elements might be template type parms. We'll check
14613 when we recurse. */
14614 && TREE_CODE (arg) != ARRAY_TYPE
14615 /* We check the cv-qualifiers when unifying with template type
14616 parameters below. We want to allow ARG `const T' to unify with
14617 PARM `T' for example, when computing which of two templates
14618 is more specialized, for example. */
14619 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14620 && !check_cv_quals_for_unify (strict_in, arg, parm))
14623 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14624 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14625 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14626 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14627 strict &= ~UNIFY_ALLOW_DERIVED;
14628 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14629 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14631 switch (TREE_CODE (parm))
14633 case TYPENAME_TYPE:
14635 case UNBOUND_CLASS_TEMPLATE:
14636 /* In a type which contains a nested-name-specifier, template
14637 argument values cannot be deduced for template parameters used
14638 within the nested-name-specifier. */
14641 case TEMPLATE_TYPE_PARM:
14642 case TEMPLATE_TEMPLATE_PARM:
14643 case BOUND_TEMPLATE_TEMPLATE_PARM:
14644 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14645 if (tparm == error_mark_node)
14648 if (TEMPLATE_TYPE_LEVEL (parm)
14649 != template_decl_level (tparm))
14650 /* The PARM is not one we're trying to unify. Just check
14651 to see if it matches ARG. */
14652 return (TREE_CODE (arg) == TREE_CODE (parm)
14653 && same_type_p (parm, arg)) ? 0 : 1;
14654 idx = TEMPLATE_TYPE_IDX (parm);
14655 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14656 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14658 /* Check for mixed types and values. */
14659 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14660 && TREE_CODE (tparm) != TYPE_DECL)
14661 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14662 && TREE_CODE (tparm) != TEMPLATE_DECL))
14665 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14667 /* ARG must be constructed from a template class or a template
14668 template parameter. */
14669 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14670 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14674 tree parmvec = TYPE_TI_ARGS (parm);
14675 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14677 = DECL_INNERMOST_TEMPLATE_PARMS
14678 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14680 int parm_variadic_p = 0;
14682 /* The resolution to DR150 makes clear that default
14683 arguments for an N-argument may not be used to bind T
14684 to a template template parameter with fewer than N
14685 parameters. It is not safe to permit the binding of
14686 default arguments as an extension, as that may change
14687 the meaning of a conforming program. Consider:
14689 struct Dense { static const unsigned int dim = 1; };
14691 template <template <typename> class View,
14693 void operator+(float, View<Block> const&);
14695 template <typename Block,
14696 unsigned int Dim = Block::dim>
14697 struct Lvalue_proxy { operator float() const; };
14701 Lvalue_proxy<Dense> p;
14706 Here, if Lvalue_proxy is permitted to bind to View, then
14707 the global operator+ will be used; if they are not, the
14708 Lvalue_proxy will be converted to float. */
14709 if (coerce_template_parms (parm_parms,
14711 TYPE_TI_TEMPLATE (parm),
14713 /*require_all_args=*/true,
14714 /*use_default_args=*/false)
14715 == error_mark_node)
14718 /* Deduce arguments T, i from TT<T> or TT<i>.
14719 We check each element of PARMVEC and ARGVEC individually
14720 rather than the whole TREE_VEC since they can have
14721 different number of elements. */
14723 parmvec = expand_template_argument_pack (parmvec);
14724 argvec = expand_template_argument_pack (argvec);
14726 len = TREE_VEC_LENGTH (parmvec);
14728 /* Check if the parameters end in a pack, making them
14731 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14732 parm_variadic_p = 1;
14734 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14737 for (i = 0; i < len - parm_variadic_p; ++i)
14739 if (unify (tparms, targs,
14740 TREE_VEC_ELT (parmvec, i),
14741 TREE_VEC_ELT (argvec, i),
14746 if (parm_variadic_p
14747 && unify_pack_expansion (tparms, targs,
14750 /*call_args_p=*/false,
14754 arg = TYPE_TI_TEMPLATE (arg);
14756 /* Fall through to deduce template name. */
14759 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14760 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14762 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14764 /* Simple cases: Value already set, does match or doesn't. */
14765 if (targ != NULL_TREE && template_args_equal (targ, arg))
14772 /* If PARM is `const T' and ARG is only `int', we don't have
14773 a match unless we are allowing additional qualification.
14774 If ARG is `const int' and PARM is just `T' that's OK;
14775 that binds `const int' to `T'. */
14776 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14780 /* Consider the case where ARG is `const volatile int' and
14781 PARM is `const T'. Then, T should be `volatile int'. */
14782 arg = cp_build_qualified_type_real
14783 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14784 if (arg == error_mark_node)
14787 /* Simple cases: Value already set, does match or doesn't. */
14788 if (targ != NULL_TREE && same_type_p (targ, arg))
14793 /* Make sure that ARG is not a variable-sized array. (Note
14794 that were talking about variable-sized arrays (like
14795 `int[n]'), rather than arrays of unknown size (like
14796 `int[]').) We'll get very confused by such a type since
14797 the bound of the array will not be computable in an
14798 instantiation. Besides, such types are not allowed in
14799 ISO C++, so we can do as we please here. */
14800 if (variably_modified_type_p (arg, NULL_TREE))
14803 /* Strip typedefs as in convert_template_argument. */
14804 arg = strip_typedefs (arg);
14807 /* If ARG is a parameter pack or an expansion, we cannot unify
14808 against it unless PARM is also a parameter pack. */
14809 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14810 && !template_parameter_pack_p (parm))
14813 /* If the argument deduction results is a METHOD_TYPE,
14814 then there is a problem.
14815 METHOD_TYPE doesn't map to any real C++ type the result of
14816 the deduction can not be of that type. */
14817 if (TREE_CODE (arg) == METHOD_TYPE)
14820 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14823 case TEMPLATE_PARM_INDEX:
14824 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14825 if (tparm == error_mark_node)
14828 if (TEMPLATE_PARM_LEVEL (parm)
14829 != template_decl_level (tparm))
14830 /* The PARM is not one we're trying to unify. Just check
14831 to see if it matches ARG. */
14832 return !(TREE_CODE (arg) == TREE_CODE (parm)
14833 && cp_tree_equal (parm, arg));
14835 idx = TEMPLATE_PARM_IDX (parm);
14836 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14839 return !cp_tree_equal (targ, arg);
14841 /* [temp.deduct.type] If, in the declaration of a function template
14842 with a non-type template-parameter, the non-type
14843 template-parameter is used in an expression in the function
14844 parameter-list and, if the corresponding template-argument is
14845 deduced, the template-argument type shall match the type of the
14846 template-parameter exactly, except that a template-argument
14847 deduced from an array bound may be of any integral type.
14848 The non-type parameter might use already deduced type parameters. */
14849 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14850 if (!TREE_TYPE (arg))
14851 /* Template-parameter dependent expression. Just accept it for now.
14852 It will later be processed in convert_template_argument. */
14854 else if (same_type_p (TREE_TYPE (arg), tparm))
14856 else if ((strict & UNIFY_ALLOW_INTEGER)
14857 && (TREE_CODE (tparm) == INTEGER_TYPE
14858 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14859 /* Convert the ARG to the type of PARM; the deduced non-type
14860 template argument must exactly match the types of the
14861 corresponding parameter. */
14862 arg = fold (build_nop (tparm, arg));
14863 else if (uses_template_parms (tparm))
14864 /* We haven't deduced the type of this parameter yet. Try again
14870 /* If ARG is a parameter pack or an expansion, we cannot unify
14871 against it unless PARM is also a parameter pack. */
14872 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14873 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14876 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14881 /* A pointer-to-member constant can be unified only with
14882 another constant. */
14883 if (TREE_CODE (arg) != PTRMEM_CST)
14886 /* Just unify the class member. It would be useless (and possibly
14887 wrong, depending on the strict flags) to unify also
14888 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14889 arg refer to the same variable, even if through different
14890 classes. For instance:
14892 struct A { int x; };
14895 Unification of &A::x and &B::x must succeed. */
14896 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14897 PTRMEM_CST_MEMBER (arg), strict);
14902 if (TREE_CODE (arg) != POINTER_TYPE)
14905 /* [temp.deduct.call]
14907 A can be another pointer or pointer to member type that can
14908 be converted to the deduced A via a qualification
14909 conversion (_conv.qual_).
14911 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14912 This will allow for additional cv-qualification of the
14913 pointed-to types if appropriate. */
14915 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14916 /* The derived-to-base conversion only persists through one
14917 level of pointers. */
14918 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14920 return unify (tparms, targs, TREE_TYPE (parm),
14921 TREE_TYPE (arg), strict);
14924 case REFERENCE_TYPE:
14925 if (TREE_CODE (arg) != REFERENCE_TYPE)
14927 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14928 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14931 if (TREE_CODE (arg) != ARRAY_TYPE)
14933 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14934 != (TYPE_DOMAIN (arg) == NULL_TREE))
14936 if (TYPE_DOMAIN (parm) != NULL_TREE)
14943 /* Our representation of array types uses "N - 1" as the
14944 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14945 not an integer constant. We cannot unify arbitrarily
14946 complex expressions, so we eliminate the MINUS_EXPRs
14948 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14949 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14952 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14953 parm_max = TREE_OPERAND (parm_max, 0);
14955 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14956 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14959 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14960 trying to unify the type of a variable with the type
14961 of a template parameter. For example:
14963 template <unsigned int N>
14964 void f (char (&) [N]);
14971 Here, the type of the ARG will be "int [g(i)]", and
14972 may be a SAVE_EXPR, etc. */
14973 if (TREE_CODE (arg_max) != MINUS_EXPR)
14975 arg_max = TREE_OPERAND (arg_max, 0);
14978 /* If only one of the bounds used a MINUS_EXPR, compensate
14979 by adding one to the other bound. */
14980 if (parm_cst && !arg_cst)
14981 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14985 else if (arg_cst && !parm_cst)
14986 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14991 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14994 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14995 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15002 case ENUMERAL_TYPE:
15004 if (TREE_CODE (arg) != TREE_CODE (parm))
15007 /* We have already checked cv-qualification at the top of the
15009 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15012 /* As far as unification is concerned, this wins. Later checks
15013 will invalidate it if necessary. */
15016 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15017 /* Type INTEGER_CST can come from ordinary constant template args. */
15019 while (TREE_CODE (arg) == NOP_EXPR)
15020 arg = TREE_OPERAND (arg, 0);
15022 if (TREE_CODE (arg) != INTEGER_CST)
15024 return !tree_int_cst_equal (parm, arg);
15029 if (TREE_CODE (arg) != TREE_VEC)
15031 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15033 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15034 if (unify (tparms, targs,
15035 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15043 if (TREE_CODE (arg) != TREE_CODE (parm))
15046 if (TYPE_PTRMEMFUNC_P (parm))
15048 if (!TYPE_PTRMEMFUNC_P (arg))
15051 return unify (tparms, targs,
15052 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15053 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15057 if (CLASSTYPE_TEMPLATE_INFO (parm))
15059 tree t = NULL_TREE;
15061 if (strict_in & UNIFY_ALLOW_DERIVED)
15063 /* First, we try to unify the PARM and ARG directly. */
15064 t = try_class_unification (tparms, targs,
15069 /* Fallback to the special case allowed in
15070 [temp.deduct.call]:
15072 If P is a class, and P has the form
15073 template-id, then A can be a derived class of
15074 the deduced A. Likewise, if P is a pointer to
15075 a class of the form template-id, A can be a
15076 pointer to a derived class pointed to by the
15078 t = get_template_base (tparms, targs, parm, arg);
15084 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15085 && (CLASSTYPE_TI_TEMPLATE (parm)
15086 == CLASSTYPE_TI_TEMPLATE (arg)))
15087 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15088 Then, we should unify `int' and `U'. */
15091 /* There's no chance of unification succeeding. */
15094 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15095 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15097 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15102 case FUNCTION_TYPE:
15104 unsigned int nargs;
15109 if (TREE_CODE (arg) != TREE_CODE (parm))
15112 /* CV qualifications for methods can never be deduced, they must
15113 match exactly. We need to check them explicitly here,
15114 because type_unification_real treats them as any other
15115 cv-qualified parameter. */
15116 if (TREE_CODE (parm) == METHOD_TYPE
15117 && (!check_cv_quals_for_unify
15119 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
15120 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
15123 if (unify (tparms, targs, TREE_TYPE (parm),
15124 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15127 nargs = list_length (TYPE_ARG_TYPES (arg));
15128 args = XALLOCAVEC (tree, nargs);
15129 for (a = TYPE_ARG_TYPES (arg), i = 0;
15130 a != NULL_TREE && a != void_list_node;
15131 a = TREE_CHAIN (a), ++i)
15132 args[i] = TREE_VALUE (a);
15135 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15136 args, nargs, 1, DEDUCE_EXACT,
15141 /* Unify a pointer to member with a pointer to member function, which
15142 deduces the type of the member as a function type. */
15143 if (TYPE_PTRMEMFUNC_P (arg))
15148 /* Check top-level cv qualifiers */
15149 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15152 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15153 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15156 /* Determine the type of the function we are unifying against. */
15157 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15159 build_function_type (TREE_TYPE (method_type),
15160 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15162 /* Extract the cv-qualifiers of the member function from the
15163 implicit object parameter and place them on the function
15164 type to be restored later. */
15165 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15166 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15169 if (TREE_CODE (arg) != OFFSET_TYPE)
15171 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15172 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15174 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15178 if (DECL_TEMPLATE_PARM_P (parm))
15179 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15180 if (arg != integral_constant_value (parm))
15185 case TEMPLATE_DECL:
15186 /* Matched cases are handled by the ARG == PARM test above. */
15190 /* A non-type template parameter that is a variable should be a
15191 an integral constant, in which case, it whould have been
15192 folded into its (constant) value. So we should not be getting
15193 a variable here. */
15194 gcc_unreachable ();
15196 case TYPE_ARGUMENT_PACK:
15197 case NONTYPE_ARGUMENT_PACK:
15199 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15200 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15201 int i, len = TREE_VEC_LENGTH (packed_parms);
15202 int argslen = TREE_VEC_LENGTH (packed_args);
15203 int parm_variadic_p = 0;
15205 for (i = 0; i < len; ++i)
15207 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15210 /* We can unify against something with a trailing
15212 parm_variadic_p = 1;
15214 /* Since there is something following the pack
15215 expansion, we cannot unify this template argument
15222 /* If we don't have enough arguments to satisfy the parameters
15223 (not counting the pack expression at the end), or we have
15224 too many arguments for a parameter list that doesn't end in
15225 a pack expression, we can't unify. */
15226 if (argslen < (len - parm_variadic_p)
15227 || (argslen > len && !parm_variadic_p))
15230 /* Unify all of the parameters that precede the (optional)
15231 pack expression. */
15232 for (i = 0; i < len - parm_variadic_p; ++i)
15234 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15235 TREE_VEC_ELT (packed_args, i), strict))
15239 if (parm_variadic_p)
15240 return unify_pack_expansion (tparms, targs,
15241 packed_parms, packed_args,
15242 strict, /*call_args_p=*/false,
15250 case DECLTYPE_TYPE:
15251 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
15256 /* Unification fails if we hit an error node. */
15260 gcc_assert (EXPR_P (parm));
15262 /* We must be looking at an expression. This can happen with
15266 void foo(S<I>, S<I + 2>);
15268 This is a "nondeduced context":
15272 The nondeduced contexts are:
15274 --A type that is a template-id in which one or more of
15275 the template-arguments is an expression that references
15276 a template-parameter.
15278 In these cases, we assume deduction succeeded, but don't
15279 actually infer any unifications. */
15281 if (!uses_template_parms (parm)
15282 && !template_args_equal (parm, arg))
15289 /* Note that DECL can be defined in this translation unit, if
15293 mark_definable (tree decl)
15296 DECL_NOT_REALLY_EXTERN (decl) = 1;
15297 FOR_EACH_CLONE (clone, decl)
15298 DECL_NOT_REALLY_EXTERN (clone) = 1;
15301 /* Called if RESULT is explicitly instantiated, or is a member of an
15302 explicitly instantiated class. */
15305 mark_decl_instantiated (tree result, int extern_p)
15307 SET_DECL_EXPLICIT_INSTANTIATION (result);
15309 /* If this entity has already been written out, it's too late to
15310 make any modifications. */
15311 if (TREE_ASM_WRITTEN (result))
15314 if (TREE_CODE (result) != FUNCTION_DECL)
15315 /* The TREE_PUBLIC flag for function declarations will have been
15316 set correctly by tsubst. */
15317 TREE_PUBLIC (result) = 1;
15319 /* This might have been set by an earlier implicit instantiation. */
15320 DECL_COMDAT (result) = 0;
15323 DECL_NOT_REALLY_EXTERN (result) = 0;
15326 mark_definable (result);
15327 /* Always make artificials weak. */
15328 if (DECL_ARTIFICIAL (result) && flag_weak)
15329 comdat_linkage (result);
15330 /* For WIN32 we also want to put explicit instantiations in
15331 linkonce sections. */
15332 else if (TREE_PUBLIC (result))
15333 maybe_make_one_only (result);
15336 /* If EXTERN_P, then this function will not be emitted -- unless
15337 followed by an explicit instantiation, at which point its linkage
15338 will be adjusted. If !EXTERN_P, then this function will be
15339 emitted here. In neither circumstance do we want
15340 import_export_decl to adjust the linkage. */
15341 DECL_INTERFACE_KNOWN (result) = 1;
15344 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
15345 important template arguments. If any are missing, we check whether
15346 they're important by using error_mark_node for substituting into any
15347 args that were used for partial ordering (the ones between ARGS and END)
15348 and seeing if it bubbles up. */
15351 check_undeduced_parms (tree targs, tree args, tree end)
15353 bool found = false;
15355 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
15356 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
15359 TREE_VEC_ELT (targs, i) = error_mark_node;
15363 for (; args != end; args = TREE_CHAIN (args))
15365 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
15366 if (substed == error_mark_node)
15373 /* Given two function templates PAT1 and PAT2, return:
15375 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
15376 -1 if PAT2 is more specialized than PAT1.
15377 0 if neither is more specialized.
15379 LEN indicates the number of parameters we should consider
15380 (defaulted parameters should not be considered).
15382 The 1998 std underspecified function template partial ordering, and
15383 DR214 addresses the issue. We take pairs of arguments, one from
15384 each of the templates, and deduce them against each other. One of
15385 the templates will be more specialized if all the *other*
15386 template's arguments deduce against its arguments and at least one
15387 of its arguments *does* *not* deduce against the other template's
15388 corresponding argument. Deduction is done as for class templates.
15389 The arguments used in deduction have reference and top level cv
15390 qualifiers removed. Iff both arguments were originally reference
15391 types *and* deduction succeeds in both directions, the template
15392 with the more cv-qualified argument wins for that pairing (if
15393 neither is more cv-qualified, they both are equal). Unlike regular
15394 deduction, after all the arguments have been deduced in this way,
15395 we do *not* verify the deduced template argument values can be
15396 substituted into non-deduced contexts.
15398 The logic can be a bit confusing here, because we look at deduce1 and
15399 targs1 to see if pat2 is at least as specialized, and vice versa; if we
15400 can find template arguments for pat1 to make arg1 look like arg2, that
15401 means that arg2 is at least as specialized as arg1. */
15404 more_specialized_fn (tree pat1, tree pat2, int len)
15406 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
15407 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
15408 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
15409 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
15410 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
15411 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
15412 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
15413 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
15414 tree origs1, origs2;
15415 bool lose1 = false;
15416 bool lose2 = false;
15418 /* Remove the this parameter from non-static member functions. If
15419 one is a non-static member function and the other is not a static
15420 member function, remove the first parameter from that function
15421 also. This situation occurs for operator functions where we
15422 locate both a member function (with this pointer) and non-member
15423 operator (with explicit first operand). */
15424 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
15426 len--; /* LEN is the number of significant arguments for DECL1 */
15427 args1 = TREE_CHAIN (args1);
15428 if (!DECL_STATIC_FUNCTION_P (decl2))
15429 args2 = TREE_CHAIN (args2);
15431 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
15433 args2 = TREE_CHAIN (args2);
15434 if (!DECL_STATIC_FUNCTION_P (decl1))
15437 args1 = TREE_CHAIN (args1);
15441 /* If only one is a conversion operator, they are unordered. */
15442 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
15445 /* Consider the return type for a conversion function */
15446 if (DECL_CONV_FN_P (decl1))
15448 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
15449 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
15453 processing_template_decl++;
15459 /* Stop when an ellipsis is seen. */
15460 && args1 != NULL_TREE && args2 != NULL_TREE)
15462 tree arg1 = TREE_VALUE (args1);
15463 tree arg2 = TREE_VALUE (args2);
15464 int deduce1, deduce2;
15468 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15469 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15471 /* When both arguments are pack expansions, we need only
15472 unify the patterns themselves. */
15473 arg1 = PACK_EXPANSION_PATTERN (arg1);
15474 arg2 = PACK_EXPANSION_PATTERN (arg2);
15476 /* This is the last comparison we need to do. */
15480 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15482 arg1 = TREE_TYPE (arg1);
15483 quals1 = cp_type_quals (arg1);
15486 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15488 arg2 = TREE_TYPE (arg2);
15489 quals2 = cp_type_quals (arg2);
15492 if ((quals1 < 0) != (quals2 < 0))
15494 /* Only of the args is a reference, see if we should apply
15495 array/function pointer decay to it. This is not part of
15496 DR214, but is, IMHO, consistent with the deduction rules
15497 for the function call itself, and with our earlier
15498 implementation of the underspecified partial ordering
15499 rules. (nathan). */
15502 switch (TREE_CODE (arg1))
15505 arg1 = TREE_TYPE (arg1);
15507 case FUNCTION_TYPE:
15508 arg1 = build_pointer_type (arg1);
15517 switch (TREE_CODE (arg2))
15520 arg2 = TREE_TYPE (arg2);
15522 case FUNCTION_TYPE:
15523 arg2 = build_pointer_type (arg2);
15532 arg1 = TYPE_MAIN_VARIANT (arg1);
15533 arg2 = TYPE_MAIN_VARIANT (arg2);
15535 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15537 int i, len2 = list_length (args2);
15538 tree parmvec = make_tree_vec (1);
15539 tree argvec = make_tree_vec (len2);
15542 /* Setup the parameter vector, which contains only ARG1. */
15543 TREE_VEC_ELT (parmvec, 0) = arg1;
15545 /* Setup the argument vector, which contains the remaining
15547 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15548 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15550 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15551 argvec, UNIFY_ALLOW_NONE,
15552 /*call_args_p=*/false,
15555 /* We cannot deduce in the other direction, because ARG1 is
15556 a pack expansion but ARG2 is not. */
15559 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15561 int i, len1 = list_length (args1);
15562 tree parmvec = make_tree_vec (1);
15563 tree argvec = make_tree_vec (len1);
15566 /* Setup the parameter vector, which contains only ARG1. */
15567 TREE_VEC_ELT (parmvec, 0) = arg2;
15569 /* Setup the argument vector, which contains the remaining
15571 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15572 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15574 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15575 argvec, UNIFY_ALLOW_NONE,
15576 /*call_args_p=*/false,
15579 /* We cannot deduce in the other direction, because ARG2 is
15580 a pack expansion but ARG1 is not.*/
15586 /* The normal case, where neither argument is a pack
15588 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15589 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15592 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15593 arg2, then arg2 is not as specialized as arg1. */
15599 /* "If, for a given type, deduction succeeds in both directions
15600 (i.e., the types are identical after the transformations above)
15601 and if the type from the argument template is more cv-qualified
15602 than the type from the parameter template (as described above)
15603 that type is considered to be more specialized than the other. If
15604 neither type is more cv-qualified than the other then neither type
15605 is more specialized than the other." */
15607 if (deduce1 && deduce2
15608 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
15610 if ((quals1 & quals2) == quals2)
15612 if ((quals1 & quals2) == quals1)
15616 if (lose1 && lose2)
15617 /* We've failed to deduce something in either direction.
15618 These must be unordered. */
15621 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15622 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15623 /* We have already processed all of the arguments in our
15624 handing of the pack expansion type. */
15627 args1 = TREE_CHAIN (args1);
15628 args2 = TREE_CHAIN (args2);
15631 /* "In most cases, all template parameters must have values in order for
15632 deduction to succeed, but for partial ordering purposes a template
15633 parameter may remain without a value provided it is not used in the
15634 types being used for partial ordering."
15636 Thus, if we are missing any of the targs1 we need to substitute into
15637 origs1, then pat2 is not as specialized as pat1. This can happen when
15638 there is a nondeduced context. */
15639 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15641 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15644 processing_template_decl--;
15646 /* All things being equal, if the next argument is a pack expansion
15647 for one function but not for the other, prefer the
15648 non-variadic function. FIXME this is bogus; see c++/41958. */
15650 && args1 && TREE_VALUE (args1)
15651 && args2 && TREE_VALUE (args2))
15653 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
15654 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
15657 if (lose1 == lose2)
15665 /* Determine which of two partial specializations is more specialized.
15667 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15668 to the first partial specialization. The TREE_VALUE is the
15669 innermost set of template parameters for the partial
15670 specialization. PAT2 is similar, but for the second template.
15672 Return 1 if the first partial specialization is more specialized;
15673 -1 if the second is more specialized; 0 if neither is more
15676 See [temp.class.order] for information about determining which of
15677 two templates is more specialized. */
15680 more_specialized_class (tree pat1, tree pat2)
15685 bool any_deductions = false;
15687 tmpl1 = TREE_TYPE (pat1);
15688 tmpl2 = TREE_TYPE (pat2);
15690 /* Just like what happens for functions, if we are ordering between
15691 different class template specializations, we may encounter dependent
15692 types in the arguments, and we need our dependency check functions
15693 to behave correctly. */
15694 ++processing_template_decl;
15695 targs = get_class_bindings (TREE_VALUE (pat1),
15696 CLASSTYPE_TI_ARGS (tmpl1),
15697 CLASSTYPE_TI_ARGS (tmpl2));
15701 any_deductions = true;
15704 targs = get_class_bindings (TREE_VALUE (pat2),
15705 CLASSTYPE_TI_ARGS (tmpl2),
15706 CLASSTYPE_TI_ARGS (tmpl1));
15710 any_deductions = true;
15712 --processing_template_decl;
15714 /* In the case of a tie where at least one of the class templates
15715 has a parameter pack at the end, the template with the most
15716 non-packed parameters wins. */
15719 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15720 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15722 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15723 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15724 int len1 = TREE_VEC_LENGTH (args1);
15725 int len2 = TREE_VEC_LENGTH (args2);
15727 /* We don't count the pack expansion at the end. */
15728 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15730 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15735 else if (len1 < len2)
15742 /* Return the template arguments that will produce the function signature
15743 DECL from the function template FN, with the explicit template
15744 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15745 also match. Return NULL_TREE if no satisfactory arguments could be
15749 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15751 int ntparms = DECL_NTPARMS (fn);
15752 tree targs = make_tree_vec (ntparms);
15754 tree decl_arg_types;
15756 unsigned int nargs, ix;
15759 /* Substitute the explicit template arguments into the type of DECL.
15760 The call to fn_type_unification will handle substitution into the
15762 decl_type = TREE_TYPE (decl);
15763 if (explicit_args && uses_template_parms (decl_type))
15766 tree converted_args;
15768 if (DECL_TEMPLATE_INFO (decl))
15769 tmpl = DECL_TI_TEMPLATE (decl);
15771 /* We can get here for some invalid specializations. */
15775 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15776 explicit_args, NULL_TREE,
15778 /*require_all_args=*/false,
15779 /*use_default_args=*/false);
15780 if (converted_args == error_mark_node)
15783 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15784 if (decl_type == error_mark_node)
15788 /* Never do unification on the 'this' parameter. */
15789 decl_arg_types = skip_artificial_parms_for (decl,
15790 TYPE_ARG_TYPES (decl_type));
15792 nargs = list_length (decl_arg_types);
15793 args = XALLOCAVEC (tree, nargs);
15794 for (arg = decl_arg_types, ix = 0;
15795 arg != NULL_TREE && arg != void_list_node;
15796 arg = TREE_CHAIN (arg), ++ix)
15797 args[ix] = TREE_VALUE (arg);
15799 if (fn_type_unification (fn, explicit_args, targs,
15801 (check_rettype || DECL_CONV_FN_P (fn)
15802 ? TREE_TYPE (decl_type) : NULL_TREE),
15803 DEDUCE_EXACT, LOOKUP_NORMAL))
15809 /* Return the innermost template arguments that, when applied to a
15810 template specialization whose innermost template parameters are
15811 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15814 For example, suppose we have:
15816 template <class T, class U> struct S {};
15817 template <class T> struct S<T*, int> {};
15819 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15820 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15821 int}. The resulting vector will be {double}, indicating that `T'
15822 is bound to `double'. */
15825 get_class_bindings (tree tparms, tree spec_args, tree args)
15827 int i, ntparms = TREE_VEC_LENGTH (tparms);
15829 tree innermost_deduced_args;
15831 innermost_deduced_args = make_tree_vec (ntparms);
15832 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15834 deduced_args = copy_node (args);
15835 SET_TMPL_ARGS_LEVEL (deduced_args,
15836 TMPL_ARGS_DEPTH (deduced_args),
15837 innermost_deduced_args);
15840 deduced_args = innermost_deduced_args;
15842 if (unify (tparms, deduced_args,
15843 INNERMOST_TEMPLATE_ARGS (spec_args),
15844 INNERMOST_TEMPLATE_ARGS (args),
15848 for (i = 0; i < ntparms; ++i)
15849 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15852 /* Verify that nondeduced template arguments agree with the type
15853 obtained from argument deduction.
15857 struct A { typedef int X; };
15858 template <class T, class U> struct C {};
15859 template <class T> struct C<T, typename T::X> {};
15861 Then with the instantiation `C<A, int>', we can deduce that
15862 `T' is `A' but unify () does not check whether `typename T::X'
15864 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15865 if (spec_args == error_mark_node
15866 /* We only need to check the innermost arguments; the other
15867 arguments will always agree. */
15868 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15869 INNERMOST_TEMPLATE_ARGS (args)))
15872 /* Now that we have bindings for all of the template arguments,
15873 ensure that the arguments deduced for the template template
15874 parameters have compatible template parameter lists. See the use
15875 of template_template_parm_bindings_ok_p in fn_type_unification
15876 for more information. */
15877 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15880 return deduced_args;
15883 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15884 Return the TREE_LIST node with the most specialized template, if
15885 any. If there is no most specialized template, the error_mark_node
15888 Note that this function does not look at, or modify, the
15889 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15890 returned is one of the elements of INSTANTIATIONS, callers may
15891 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15892 and retrieve it from the value returned. */
15895 most_specialized_instantiation (tree templates)
15899 ++processing_template_decl;
15902 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15906 if (get_bindings (TREE_VALUE (champ),
15907 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15908 NULL_TREE, /*check_ret=*/false))
15911 if (get_bindings (TREE_VALUE (fn),
15912 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15913 NULL_TREE, /*check_ret=*/false))
15920 /* Equally specialized, move to next function. If there
15921 is no next function, nothing's most specialized. */
15922 fn = TREE_CHAIN (fn);
15930 /* Now verify that champ is better than everything earlier in the
15931 instantiation list. */
15932 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15933 if (get_bindings (TREE_VALUE (champ),
15934 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15935 NULL_TREE, /*check_ret=*/false)
15936 || !get_bindings (TREE_VALUE (fn),
15937 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15938 NULL_TREE, /*check_ret=*/false))
15944 processing_template_decl--;
15947 return error_mark_node;
15952 /* If DECL is a specialization of some template, return the most
15953 general such template. Otherwise, returns NULL_TREE.
15955 For example, given:
15957 template <class T> struct S { template <class U> void f(U); };
15959 if TMPL is `template <class U> void S<int>::f(U)' this will return
15960 the full template. This function will not trace past partial
15961 specializations, however. For example, given in addition:
15963 template <class T> struct S<T*> { template <class U> void f(U); };
15965 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15966 `template <class T> template <class U> S<T*>::f(U)'. */
15969 most_general_template (tree decl)
15971 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15972 an immediate specialization. */
15973 if (TREE_CODE (decl) == FUNCTION_DECL)
15975 if (DECL_TEMPLATE_INFO (decl)) {
15976 decl = DECL_TI_TEMPLATE (decl);
15978 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15979 template friend. */
15980 if (TREE_CODE (decl) != TEMPLATE_DECL)
15986 /* Look for more and more general templates. */
15987 while (DECL_TEMPLATE_INFO (decl))
15989 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15990 (See cp-tree.h for details.) */
15991 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15994 if (CLASS_TYPE_P (TREE_TYPE (decl))
15995 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15998 /* Stop if we run into an explicitly specialized class template. */
15999 if (!DECL_NAMESPACE_SCOPE_P (decl)
16000 && DECL_CONTEXT (decl)
16001 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16004 decl = DECL_TI_TEMPLATE (decl);
16010 /* Return the most specialized of the class template partial
16011 specializations of TMPL which can produce TYPE, a specialization of
16012 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16013 a _TYPE node corresponding to the partial specialization, while the
16014 TREE_PURPOSE is the set of template arguments that must be
16015 substituted into the TREE_TYPE in order to generate TYPE.
16017 If the choice of partial specialization is ambiguous, a diagnostic
16018 is issued, and the error_mark_node is returned. If there are no
16019 partial specializations of TMPL matching TYPE, then NULL_TREE is
16023 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16025 tree list = NULL_TREE;
16031 tree outer_args = NULL_TREE;
16033 tmpl = most_general_template (tmpl);
16034 args = CLASSTYPE_TI_ARGS (type);
16036 /* For determining which partial specialization to use, only the
16037 innermost args are interesting. */
16038 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16040 outer_args = strip_innermost_template_args (args, 1);
16041 args = INNERMOST_TEMPLATE_ARGS (args);
16044 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16046 tree partial_spec_args;
16048 tree parms = TREE_VALUE (t);
16050 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16052 ++processing_template_decl;
16058 /* Discard the outer levels of args, and then substitute in the
16059 template args from the enclosing class. */
16060 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16061 partial_spec_args = tsubst_template_args
16062 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16064 /* PARMS already refers to just the innermost parms, but the
16065 template parms in partial_spec_args had their levels lowered
16066 by tsubst, so we need to do the same for the parm list. We
16067 can't just tsubst the TREE_VEC itself, as tsubst wants to
16068 treat a TREE_VEC as an argument vector. */
16069 parms = copy_node (parms);
16070 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16071 TREE_VEC_ELT (parms, i) =
16072 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16076 partial_spec_args =
16077 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16078 add_to_template_args (outer_args,
16079 partial_spec_args),
16081 /*require_all_args=*/true,
16082 /*use_default_args=*/true);
16084 --processing_template_decl;
16086 if (partial_spec_args == error_mark_node)
16087 return error_mark_node;
16089 spec_args = get_class_bindings (parms,
16095 spec_args = add_to_template_args (outer_args, spec_args);
16096 list = tree_cons (spec_args, TREE_VALUE (t), list);
16097 TREE_TYPE (list) = TREE_TYPE (t);
16104 ambiguous_p = false;
16107 t = TREE_CHAIN (t);
16108 for (; t; t = TREE_CHAIN (t))
16110 fate = more_specialized_class (champ, t);
16117 t = TREE_CHAIN (t);
16120 ambiguous_p = true;
16129 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16131 fate = more_specialized_class (champ, t);
16134 ambiguous_p = true;
16142 char *spaces = NULL;
16143 if (!(complain & tf_error))
16144 return error_mark_node;
16145 error ("ambiguous class template instantiation for %q#T", type);
16146 str = TREE_CHAIN (list) ? _("candidates are:") : _("candidate is:");
16147 for (t = list; t; t = TREE_CHAIN (t))
16149 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16150 spaces = spaces ? spaces : get_spaces (str);
16153 return error_mark_node;
16159 /* Explicitly instantiate DECL. */
16162 do_decl_instantiation (tree decl, tree storage)
16164 tree result = NULL_TREE;
16167 if (!decl || decl == error_mark_node)
16168 /* An error occurred, for which grokdeclarator has already issued
16169 an appropriate message. */
16171 else if (! DECL_LANG_SPECIFIC (decl))
16173 error ("explicit instantiation of non-template %q#D", decl);
16176 else if (TREE_CODE (decl) == VAR_DECL)
16178 /* There is an asymmetry here in the way VAR_DECLs and
16179 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16180 the latter, the DECL we get back will be marked as a
16181 template instantiation, and the appropriate
16182 DECL_TEMPLATE_INFO will be set up. This does not happen for
16183 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16184 should handle VAR_DECLs as it currently handles
16186 if (!DECL_CLASS_SCOPE_P (decl))
16188 error ("%qD is not a static data member of a class template", decl);
16191 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16192 if (!result || TREE_CODE (result) != VAR_DECL)
16194 error ("no matching template for %qD found", decl);
16197 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16199 error ("type %qT for explicit instantiation %qD does not match "
16200 "declared type %qT", TREE_TYPE (result), decl,
16205 else if (TREE_CODE (decl) != FUNCTION_DECL)
16207 error ("explicit instantiation of %q#D", decl);
16213 /* Check for various error cases. Note that if the explicit
16214 instantiation is valid the RESULT will currently be marked as an
16215 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16216 until we get here. */
16218 if (DECL_TEMPLATE_SPECIALIZATION (result))
16220 /* DR 259 [temp.spec].
16222 Both an explicit instantiation and a declaration of an explicit
16223 specialization shall not appear in a program unless the explicit
16224 instantiation follows a declaration of the explicit specialization.
16226 For a given set of template parameters, if an explicit
16227 instantiation of a template appears after a declaration of an
16228 explicit specialization for that template, the explicit
16229 instantiation has no effect. */
16232 else if (DECL_EXPLICIT_INSTANTIATION (result))
16236 No program shall explicitly instantiate any template more
16239 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16240 the first instantiation was `extern' and the second is not,
16241 and EXTERN_P for the opposite case. */
16242 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16243 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16244 /* If an "extern" explicit instantiation follows an ordinary
16245 explicit instantiation, the template is instantiated. */
16249 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16251 error ("no matching template for %qD found", result);
16254 else if (!DECL_TEMPLATE_INFO (result))
16256 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16260 if (storage == NULL_TREE)
16262 else if (storage == ridpointers[(int) RID_EXTERN])
16264 if (!in_system_header && (cxx_dialect == cxx98))
16265 pedwarn (input_location, OPT_pedantic,
16266 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16271 error ("storage class %qD applied to template instantiation", storage);
16273 check_explicit_instantiation_namespace (result);
16274 mark_decl_instantiated (result, extern_p);
16276 instantiate_decl (result, /*defer_ok=*/1,
16277 /*expl_inst_class_mem_p=*/false);
16281 mark_class_instantiated (tree t, int extern_p)
16283 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16284 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16285 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16286 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16289 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16290 rest_of_type_compilation (t, 1);
16294 /* Called from do_type_instantiation through binding_table_foreach to
16295 do recursive instantiation for the type bound in ENTRY. */
16297 bt_instantiate_type_proc (binding_entry entry, void *data)
16299 tree storage = *(tree *) data;
16301 if (MAYBE_CLASS_TYPE_P (entry->type)
16302 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16303 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16306 /* Called from do_type_instantiation to instantiate a member
16307 (a member function or a static member variable) of an
16308 explicitly instantiated class template. */
16310 instantiate_class_member (tree decl, int extern_p)
16312 mark_decl_instantiated (decl, extern_p);
16314 instantiate_decl (decl, /*defer_ok=*/1,
16315 /*expl_inst_class_mem_p=*/true);
16318 /* Perform an explicit instantiation of template class T. STORAGE, if
16319 non-null, is the RID for extern, inline or static. COMPLAIN is
16320 nonzero if this is called from the parser, zero if called recursively,
16321 since the standard is unclear (as detailed below). */
16324 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16329 int previous_instantiation_extern_p = 0;
16331 if (TREE_CODE (t) == TYPE_DECL)
16334 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16336 error ("explicit instantiation of non-template type %qT", t);
16342 if (!COMPLETE_TYPE_P (t))
16344 if (complain & tf_error)
16345 error ("explicit instantiation of %q#T before definition of template",
16350 if (storage != NULL_TREE)
16352 if (!in_system_header)
16354 if (storage == ridpointers[(int) RID_EXTERN])
16356 if (cxx_dialect == cxx98)
16357 pedwarn (input_location, OPT_pedantic,
16358 "ISO C++ 1998 forbids the use of %<extern%> on "
16359 "explicit instantiations");
16362 pedwarn (input_location, OPT_pedantic,
16363 "ISO C++ forbids the use of %qE"
16364 " on explicit instantiations", storage);
16367 if (storage == ridpointers[(int) RID_INLINE])
16369 else if (storage == ridpointers[(int) RID_EXTERN])
16371 else if (storage == ridpointers[(int) RID_STATIC])
16375 error ("storage class %qD applied to template instantiation",
16381 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
16383 /* DR 259 [temp.spec].
16385 Both an explicit instantiation and a declaration of an explicit
16386 specialization shall not appear in a program unless the explicit
16387 instantiation follows a declaration of the explicit specialization.
16389 For a given set of template parameters, if an explicit
16390 instantiation of a template appears after a declaration of an
16391 explicit specialization for that template, the explicit
16392 instantiation has no effect. */
16395 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
16399 No program shall explicitly instantiate any template more
16402 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
16403 instantiation was `extern'. If EXTERN_P then the second is.
16404 These cases are OK. */
16405 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
16407 if (!previous_instantiation_extern_p && !extern_p
16408 && (complain & tf_error))
16409 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
16411 /* If we've already instantiated the template, just return now. */
16412 if (!CLASSTYPE_INTERFACE_ONLY (t))
16416 check_explicit_instantiation_namespace (TYPE_NAME (t));
16417 mark_class_instantiated (t, extern_p);
16425 /* In contrast to implicit instantiation, where only the
16426 declarations, and not the definitions, of members are
16427 instantiated, we have here:
16431 The explicit instantiation of a class template specialization
16432 implies the instantiation of all of its members not
16433 previously explicitly specialized in the translation unit
16434 containing the explicit instantiation.
16436 Of course, we can't instantiate member template classes, since
16437 we don't have any arguments for them. Note that the standard
16438 is unclear on whether the instantiation of the members are
16439 *explicit* instantiations or not. However, the most natural
16440 interpretation is that it should be an explicit instantiation. */
16443 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
16444 if (TREE_CODE (tmp) == FUNCTION_DECL
16445 && DECL_TEMPLATE_INSTANTIATION (tmp))
16446 instantiate_class_member (tmp, extern_p);
16448 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
16449 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
16450 instantiate_class_member (tmp, extern_p);
16452 if (CLASSTYPE_NESTED_UTDS (t))
16453 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
16454 bt_instantiate_type_proc, &storage);
16458 /* Given a function DECL, which is a specialization of TMPL, modify
16459 DECL to be a re-instantiation of TMPL with the same template
16460 arguments. TMPL should be the template into which tsubst'ing
16461 should occur for DECL, not the most general template.
16463 One reason for doing this is a scenario like this:
16466 void f(const T&, int i);
16468 void g() { f(3, 7); }
16471 void f(const T& t, const int i) { }
16473 Note that when the template is first instantiated, with
16474 instantiate_template, the resulting DECL will have no name for the
16475 first parameter, and the wrong type for the second. So, when we go
16476 to instantiate the DECL, we regenerate it. */
16479 regenerate_decl_from_template (tree decl, tree tmpl)
16481 /* The arguments used to instantiate DECL, from the most general
16486 args = DECL_TI_ARGS (decl);
16487 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
16489 /* Make sure that we can see identifiers, and compute access
16491 push_access_scope (decl);
16493 if (TREE_CODE (decl) == FUNCTION_DECL)
16501 args_depth = TMPL_ARGS_DEPTH (args);
16502 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16503 if (args_depth > parms_depth)
16504 args = get_innermost_template_args (args, parms_depth);
16506 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16507 args, tf_error, NULL_TREE);
16509 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16512 /* Merge parameter declarations. */
16513 decl_parm = skip_artificial_parms_for (decl,
16514 DECL_ARGUMENTS (decl));
16516 = skip_artificial_parms_for (code_pattern,
16517 DECL_ARGUMENTS (code_pattern));
16518 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16523 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16524 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16525 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16527 parm_type = type_decays_to (parm_type);
16528 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16529 TREE_TYPE (decl_parm) = parm_type;
16530 attributes = DECL_ATTRIBUTES (pattern_parm);
16531 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16533 DECL_ATTRIBUTES (decl_parm) = attributes;
16534 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16536 decl_parm = DECL_CHAIN (decl_parm);
16537 pattern_parm = DECL_CHAIN (pattern_parm);
16539 /* Merge any parameters that match with the function parameter
16541 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16544 tree expanded_types;
16545 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16546 the parameters in this function parameter pack. */
16547 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16548 args, tf_error, NULL_TREE);
16549 len = TREE_VEC_LENGTH (expanded_types);
16550 for (i = 0; i < len; i++)
16555 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16556 /* Rename the parameter to include the index. */
16557 DECL_NAME (decl_parm) =
16558 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16559 parm_type = TREE_VEC_ELT (expanded_types, i);
16560 parm_type = type_decays_to (parm_type);
16561 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16562 TREE_TYPE (decl_parm) = parm_type;
16563 attributes = DECL_ATTRIBUTES (pattern_parm);
16564 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16566 DECL_ATTRIBUTES (decl_parm) = attributes;
16567 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16569 decl_parm = DECL_CHAIN (decl_parm);
16572 /* Merge additional specifiers from the CODE_PATTERN. */
16573 if (DECL_DECLARED_INLINE_P (code_pattern)
16574 && !DECL_DECLARED_INLINE_P (decl))
16575 DECL_DECLARED_INLINE_P (decl) = 1;
16577 else if (TREE_CODE (decl) == VAR_DECL)
16579 DECL_INITIAL (decl) =
16580 tsubst_expr (DECL_INITIAL (code_pattern), args,
16581 tf_error, DECL_TI_TEMPLATE (decl),
16582 /*integral_constant_expression_p=*/false);
16583 if (VAR_HAD_UNKNOWN_BOUND (decl))
16584 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
16585 tf_error, DECL_TI_TEMPLATE (decl));
16588 gcc_unreachable ();
16590 pop_access_scope (decl);
16593 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16594 substituted to get DECL. */
16597 template_for_substitution (tree decl)
16599 tree tmpl = DECL_TI_TEMPLATE (decl);
16601 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16602 for the instantiation. This is not always the most general
16603 template. Consider, for example:
16606 struct S { template <class U> void f();
16607 template <> void f<int>(); };
16609 and an instantiation of S<double>::f<int>. We want TD to be the
16610 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16611 while (/* An instantiation cannot have a definition, so we need a
16612 more general template. */
16613 DECL_TEMPLATE_INSTANTIATION (tmpl)
16614 /* We must also deal with friend templates. Given:
16616 template <class T> struct S {
16617 template <class U> friend void f() {};
16620 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16621 so far as the language is concerned, but that's still
16622 where we get the pattern for the instantiation from. On
16623 other hand, if the definition comes outside the class, say:
16625 template <class T> struct S {
16626 template <class U> friend void f();
16628 template <class U> friend void f() {}
16630 we don't need to look any further. That's what the check for
16631 DECL_INITIAL is for. */
16632 || (TREE_CODE (decl) == FUNCTION_DECL
16633 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16634 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16636 /* The present template, TD, should not be a definition. If it
16637 were a definition, we should be using it! Note that we
16638 cannot restructure the loop to just keep going until we find
16639 a template with a definition, since that might go too far if
16640 a specialization was declared, but not defined. */
16641 gcc_assert (TREE_CODE (decl) != VAR_DECL
16642 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16644 /* Fetch the more general template. */
16645 tmpl = DECL_TI_TEMPLATE (tmpl);
16651 /* Returns true if we need to instantiate this template instance even if we
16652 know we aren't going to emit it.. */
16655 always_instantiate_p (tree decl)
16657 /* We always instantiate inline functions so that we can inline them. An
16658 explicit instantiation declaration prohibits implicit instantiation of
16659 non-inline functions. With high levels of optimization, we would
16660 normally inline non-inline functions -- but we're not allowed to do
16661 that for "extern template" functions. Therefore, we check
16662 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16663 return ((TREE_CODE (decl) == FUNCTION_DECL
16664 && DECL_DECLARED_INLINE_P (decl))
16665 /* And we need to instantiate static data members so that
16666 their initializers are available in integral constant
16668 || (TREE_CODE (decl) == VAR_DECL
16669 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16672 /* Produce the definition of D, a _DECL generated from a template. If
16673 DEFER_OK is nonzero, then we don't have to actually do the
16674 instantiation now; we just have to do it sometime. Normally it is
16675 an error if this is an explicit instantiation but D is undefined.
16676 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16677 explicitly instantiated class template. */
16680 instantiate_decl (tree d, int defer_ok,
16681 bool expl_inst_class_mem_p)
16683 tree tmpl = DECL_TI_TEMPLATE (d);
16690 bool pattern_defined;
16692 location_t saved_loc = input_location;
16695 /* This function should only be used to instantiate templates for
16696 functions and static member variables. */
16697 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16698 || TREE_CODE (d) == VAR_DECL);
16700 /* Variables are never deferred; if instantiation is required, they
16701 are instantiated right away. That allows for better code in the
16702 case that an expression refers to the value of the variable --
16703 if the variable has a constant value the referring expression can
16704 take advantage of that fact. */
16705 if (TREE_CODE (d) == VAR_DECL)
16708 /* Don't instantiate cloned functions. Instead, instantiate the
16709 functions they cloned. */
16710 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16711 d = DECL_CLONED_FUNCTION (d);
16713 if (DECL_TEMPLATE_INSTANTIATED (d)
16714 || DECL_TEMPLATE_SPECIALIZATION (d))
16715 /* D has already been instantiated or explicitly specialized, so
16716 there's nothing for us to do here.
16718 It might seem reasonable to check whether or not D is an explicit
16719 instantiation, and, if so, stop here. But when an explicit
16720 instantiation is deferred until the end of the compilation,
16721 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16722 the instantiation. */
16725 /* Check to see whether we know that this template will be
16726 instantiated in some other file, as with "extern template"
16728 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16730 /* In general, we do not instantiate such templates. */
16731 if (external_p && !always_instantiate_p (d))
16734 gen_tmpl = most_general_template (tmpl);
16735 gen_args = DECL_TI_ARGS (d);
16737 if (tmpl != gen_tmpl)
16738 /* We should already have the extra args. */
16739 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16740 == TMPL_ARGS_DEPTH (gen_args));
16741 /* And what's in the hash table should match D. */
16742 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16743 || spec == NULL_TREE);
16745 /* This needs to happen before any tsubsting. */
16746 if (! push_tinst_level (d))
16749 timevar_push (TV_PARSE);
16751 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16752 for the instantiation. */
16753 td = template_for_substitution (d);
16754 code_pattern = DECL_TEMPLATE_RESULT (td);
16756 /* We should never be trying to instantiate a member of a class
16757 template or partial specialization. */
16758 gcc_assert (d != code_pattern);
16760 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16761 || DECL_TEMPLATE_SPECIALIZATION (td))
16762 /* In the case of a friend template whose definition is provided
16763 outside the class, we may have too many arguments. Drop the
16764 ones we don't need. The same is true for specializations. */
16765 args = get_innermost_template_args
16766 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16770 if (TREE_CODE (d) == FUNCTION_DECL)
16771 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16773 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16775 /* We may be in the middle of deferred access check. Disable it now. */
16776 push_deferring_access_checks (dk_no_deferred);
16778 /* Unless an explicit instantiation directive has already determined
16779 the linkage of D, remember that a definition is available for
16781 if (pattern_defined
16782 && !DECL_INTERFACE_KNOWN (d)
16783 && !DECL_NOT_REALLY_EXTERN (d))
16784 mark_definable (d);
16786 input_location = DECL_SOURCE_LOCATION (d);
16788 /* If D is a member of an explicitly instantiated class template,
16789 and no definition is available, treat it like an implicit
16791 if (!pattern_defined && expl_inst_class_mem_p
16792 && DECL_EXPLICIT_INSTANTIATION (d))
16794 DECL_NOT_REALLY_EXTERN (d) = 0;
16795 DECL_INTERFACE_KNOWN (d) = 0;
16796 SET_DECL_IMPLICIT_INSTANTIATION (d);
16799 /* Recheck the substitutions to obtain any warning messages
16800 about ignoring cv qualifiers. Don't do this for artificial decls,
16801 as it breaks the context-sensitive substitution for lambda op(). */
16802 if (!defer_ok && !DECL_ARTIFICIAL (d))
16804 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16805 tree type = TREE_TYPE (gen);
16807 /* Make sure that we can see identifiers, and compute access
16808 correctly. D is already the target FUNCTION_DECL with the
16810 push_access_scope (d);
16812 if (TREE_CODE (gen) == FUNCTION_DECL)
16814 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16815 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16817 /* Don't simply tsubst the function type, as that will give
16818 duplicate warnings about poor parameter qualifications.
16819 The function arguments are the same as the decl_arguments
16820 without the top level cv qualifiers. */
16821 type = TREE_TYPE (type);
16823 tsubst (type, gen_args, tf_warning_or_error, d);
16825 pop_access_scope (d);
16828 /* Defer all other templates, unless we have been explicitly
16829 forbidden from doing so. */
16830 if (/* If there is no definition, we cannot instantiate the
16833 /* If it's OK to postpone instantiation, do so. */
16835 /* If this is a static data member that will be defined
16836 elsewhere, we don't want to instantiate the entire data
16837 member, but we do want to instantiate the initializer so that
16838 we can substitute that elsewhere. */
16839 || (external_p && TREE_CODE (d) == VAR_DECL))
16841 /* The definition of the static data member is now required so
16842 we must substitute the initializer. */
16843 if (TREE_CODE (d) == VAR_DECL
16844 && !DECL_INITIAL (d)
16845 && DECL_INITIAL (code_pattern))
16850 ns = decl_namespace_context (d);
16851 push_nested_namespace (ns);
16852 push_nested_class (DECL_CONTEXT (d));
16853 init = tsubst_expr (DECL_INITIAL (code_pattern),
16855 tf_warning_or_error, NULL_TREE,
16856 /*integral_constant_expression_p=*/false);
16857 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16858 /*asmspec_tree=*/NULL_TREE,
16859 LOOKUP_ONLYCONVERTING);
16860 pop_nested_class ();
16861 pop_nested_namespace (ns);
16864 /* We restore the source position here because it's used by
16865 add_pending_template. */
16866 input_location = saved_loc;
16868 if (at_eof && !pattern_defined
16869 && DECL_EXPLICIT_INSTANTIATION (d)
16870 && DECL_NOT_REALLY_EXTERN (d))
16873 The definition of a non-exported function template, a
16874 non-exported member function template, or a non-exported
16875 member function or static data member of a class template
16876 shall be present in every translation unit in which it is
16877 explicitly instantiated. */
16878 permerror (input_location, "explicit instantiation of %qD "
16879 "but no definition available", d);
16881 /* ??? Historically, we have instantiated inline functions, even
16882 when marked as "extern template". */
16883 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16884 add_pending_template (d);
16887 /* Tell the repository that D is available in this translation unit
16888 -- and see if it is supposed to be instantiated here. */
16889 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16891 /* In a PCH file, despite the fact that the repository hasn't
16892 requested instantiation in the PCH it is still possible that
16893 an instantiation will be required in a file that includes the
16896 add_pending_template (d);
16897 /* Instantiate inline functions so that the inliner can do its
16898 job, even though we'll not be emitting a copy of this
16900 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16904 need_push = !cfun || !global_bindings_p ();
16906 push_to_top_level ();
16908 /* Mark D as instantiated so that recursive calls to
16909 instantiate_decl do not try to instantiate it again. */
16910 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16912 /* Regenerate the declaration in case the template has been modified
16913 by a subsequent redeclaration. */
16914 regenerate_decl_from_template (d, td);
16916 /* We already set the file and line above. Reset them now in case
16917 they changed as a result of calling regenerate_decl_from_template. */
16918 input_location = DECL_SOURCE_LOCATION (d);
16920 if (TREE_CODE (d) == VAR_DECL)
16924 /* Clear out DECL_RTL; whatever was there before may not be right
16925 since we've reset the type of the declaration. */
16926 SET_DECL_RTL (d, NULL);
16927 DECL_IN_AGGR_P (d) = 0;
16929 /* The initializer is placed in DECL_INITIAL by
16930 regenerate_decl_from_template. Pull it out so that
16931 cp_finish_decl can process it. */
16932 init = DECL_INITIAL (d);
16933 DECL_INITIAL (d) = NULL_TREE;
16934 DECL_INITIALIZED_P (d) = 0;
16936 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16937 initializer. That function will defer actual emission until
16938 we have a chance to determine linkage. */
16939 DECL_EXTERNAL (d) = 0;
16941 /* Enter the scope of D so that access-checking works correctly. */
16942 push_nested_class (DECL_CONTEXT (d));
16943 cp_finish_decl (d, init, false, NULL_TREE, 0);
16944 pop_nested_class ();
16946 else if (TREE_CODE (d) == FUNCTION_DECL)
16948 htab_t saved_local_specializations;
16953 /* Save away the current list, in case we are instantiating one
16954 template from within the body of another. */
16955 saved_local_specializations = local_specializations;
16957 /* Set up the list of local specializations. */
16958 local_specializations = htab_create (37,
16959 hash_local_specialization,
16960 eq_local_specializations,
16963 /* Set up context. */
16964 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16966 /* Create substitution entries for the parameters. */
16967 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16968 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16969 spec_parm = DECL_ARGUMENTS (d);
16970 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16972 register_local_specialization (spec_parm, tmpl_parm);
16973 spec_parm = skip_artificial_parms_for (d, spec_parm);
16974 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16976 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16978 register_local_specialization (spec_parm, tmpl_parm);
16979 tmpl_parm = DECL_CHAIN (tmpl_parm);
16980 spec_parm = DECL_CHAIN (spec_parm);
16982 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16984 /* Register the (value) argument pack as a specialization of
16985 TMPL_PARM, then move on. */
16986 tree argpack = make_fnparm_pack (spec_parm);
16987 register_local_specialization (argpack, tmpl_parm);
16988 tmpl_parm = DECL_CHAIN (tmpl_parm);
16989 spec_parm = NULL_TREE;
16991 gcc_assert (!spec_parm);
16993 /* Substitute into the body of the function. */
16994 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16995 tf_warning_or_error, tmpl,
16996 /*integral_constant_expression_p=*/false);
16998 /* Set the current input_location to the end of the function
16999 so that finish_function knows where we are. */
17000 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17002 /* We don't need the local specializations any more. */
17003 htab_delete (local_specializations);
17004 local_specializations = saved_local_specializations;
17006 /* Finish the function. */
17007 d = finish_function (0);
17008 expand_or_defer_fn (d);
17011 /* We're not deferring instantiation any more. */
17012 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17015 pop_from_top_level ();
17018 input_location = saved_loc;
17019 pop_deferring_access_checks ();
17020 pop_tinst_level ();
17022 timevar_pop (TV_PARSE);
17027 /* Run through the list of templates that we wish we could
17028 instantiate, and instantiate any we can. RETRIES is the
17029 number of times we retry pending template instantiation. */
17032 instantiate_pending_templates (int retries)
17035 location_t saved_loc = input_location;
17037 /* Instantiating templates may trigger vtable generation. This in turn
17038 may require further template instantiations. We place a limit here
17039 to avoid infinite loop. */
17040 if (pending_templates && retries >= max_tinst_depth)
17042 tree decl = pending_templates->tinst->decl;
17044 error ("template instantiation depth exceeds maximum of %d"
17045 " instantiating %q+D, possibly from virtual table generation"
17046 " (use -ftemplate-depth= to increase the maximum)",
17047 max_tinst_depth, decl);
17048 if (TREE_CODE (decl) == FUNCTION_DECL)
17049 /* Pretend that we defined it. */
17050 DECL_INITIAL (decl) = error_mark_node;
17056 struct pending_template **t = &pending_templates;
17057 struct pending_template *last = NULL;
17061 tree instantiation = reopen_tinst_level ((*t)->tinst);
17062 bool complete = false;
17064 if (TYPE_P (instantiation))
17068 if (!COMPLETE_TYPE_P (instantiation))
17070 instantiate_class_template (instantiation);
17071 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17072 for (fn = TYPE_METHODS (instantiation);
17074 fn = TREE_CHAIN (fn))
17075 if (! DECL_ARTIFICIAL (fn))
17076 instantiate_decl (fn,
17078 /*expl_inst_class_mem_p=*/false);
17079 if (COMPLETE_TYPE_P (instantiation))
17083 complete = COMPLETE_TYPE_P (instantiation);
17087 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17088 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17091 = instantiate_decl (instantiation,
17093 /*expl_inst_class_mem_p=*/false);
17094 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17098 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17099 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17103 /* If INSTANTIATION has been instantiated, then we don't
17104 need to consider it again in the future. */
17112 current_tinst_level = NULL;
17114 last_pending_template = last;
17116 while (reconsider);
17118 input_location = saved_loc;
17121 /* Substitute ARGVEC into T, which is a list of initializers for
17122 either base class or a non-static data member. The TREE_PURPOSEs
17123 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17124 instantiate_decl. */
17127 tsubst_initializer_list (tree t, tree argvec)
17129 tree inits = NULL_TREE;
17131 for (; t; t = TREE_CHAIN (t))
17135 tree expanded_bases = NULL_TREE;
17136 tree expanded_arguments = NULL_TREE;
17139 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17144 /* Expand the base class expansion type into separate base
17146 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17147 tf_warning_or_error,
17149 if (expanded_bases == error_mark_node)
17152 /* We'll be building separate TREE_LISTs of arguments for
17154 len = TREE_VEC_LENGTH (expanded_bases);
17155 expanded_arguments = make_tree_vec (len);
17156 for (i = 0; i < len; i++)
17157 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17159 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17160 expand each argument in the TREE_VALUE of t. */
17161 expr = make_node (EXPR_PACK_EXPANSION);
17162 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17163 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17165 if (TREE_VALUE (t) == void_type_node)
17166 /* VOID_TYPE_NODE is used to indicate
17167 value-initialization. */
17169 for (i = 0; i < len; i++)
17170 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17174 /* Substitute parameter packs into each argument in the
17176 in_base_initializer = 1;
17177 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17179 tree expanded_exprs;
17181 /* Expand the argument. */
17182 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17184 = tsubst_pack_expansion (expr, argvec,
17185 tf_warning_or_error,
17187 if (expanded_exprs == error_mark_node)
17190 /* Prepend each of the expanded expressions to the
17191 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17192 for (i = 0; i < len; i++)
17194 TREE_VEC_ELT (expanded_arguments, i) =
17195 tree_cons (NULL_TREE,
17196 TREE_VEC_ELT (expanded_exprs, i),
17197 TREE_VEC_ELT (expanded_arguments, i));
17200 in_base_initializer = 0;
17202 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17203 since we built them backwards. */
17204 for (i = 0; i < len; i++)
17206 TREE_VEC_ELT (expanded_arguments, i) =
17207 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17212 for (i = 0; i < len; ++i)
17214 if (expanded_bases)
17216 decl = TREE_VEC_ELT (expanded_bases, i);
17217 decl = expand_member_init (decl);
17218 init = TREE_VEC_ELT (expanded_arguments, i);
17222 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17223 tf_warning_or_error, NULL_TREE);
17225 decl = expand_member_init (decl);
17226 if (decl && !DECL_P (decl))
17227 in_base_initializer = 1;
17229 init = tsubst_expr (TREE_VALUE (t), argvec,
17230 tf_warning_or_error, NULL_TREE,
17231 /*integral_constant_expression_p=*/false);
17232 in_base_initializer = 0;
17237 init = build_tree_list (decl, init);
17238 TREE_CHAIN (init) = inits;
17246 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17249 set_current_access_from_decl (tree decl)
17251 if (TREE_PRIVATE (decl))
17252 current_access_specifier = access_private_node;
17253 else if (TREE_PROTECTED (decl))
17254 current_access_specifier = access_protected_node;
17256 current_access_specifier = access_public_node;
17259 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17260 is the instantiation (which should have been created with
17261 start_enum) and ARGS are the template arguments to use. */
17264 tsubst_enum (tree tag, tree newtag, tree args)
17268 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17273 decl = TREE_VALUE (e);
17274 /* Note that in a template enum, the TREE_VALUE is the
17275 CONST_DECL, not the corresponding INTEGER_CST. */
17276 value = tsubst_expr (DECL_INITIAL (decl),
17277 args, tf_warning_or_error, NULL_TREE,
17278 /*integral_constant_expression_p=*/true);
17280 /* Give this enumeration constant the correct access. */
17281 set_current_access_from_decl (decl);
17283 /* Actually build the enumerator itself. */
17284 build_enumerator (DECL_NAME (decl), value, newtag);
17287 finish_enum (newtag);
17288 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17289 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17292 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17293 its type -- but without substituting the innermost set of template
17294 arguments. So, innermost set of template parameters will appear in
17298 get_mostly_instantiated_function_type (tree decl)
17306 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17307 targs = DECL_TI_ARGS (decl);
17308 tparms = DECL_TEMPLATE_PARMS (tmpl);
17309 parm_depth = TMPL_PARMS_DEPTH (tparms);
17311 /* There should be as many levels of arguments as there are levels
17313 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
17315 fn_type = TREE_TYPE (tmpl);
17317 if (parm_depth == 1)
17318 /* No substitution is necessary. */
17322 int i, save_access_control;
17325 /* Replace the innermost level of the TARGS with NULL_TREEs to
17326 let tsubst know not to substitute for those parameters. */
17327 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
17328 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
17329 SET_TMPL_ARGS_LEVEL (partial_args, i,
17330 TMPL_ARGS_LEVEL (targs, i));
17331 SET_TMPL_ARGS_LEVEL (partial_args,
17332 TMPL_ARGS_DEPTH (targs),
17333 make_tree_vec (DECL_NTPARMS (tmpl)));
17335 /* Disable access control as this function is used only during
17337 save_access_control = flag_access_control;
17338 flag_access_control = 0;
17340 ++processing_template_decl;
17341 /* Now, do the (partial) substitution to figure out the
17342 appropriate function type. */
17343 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
17344 --processing_template_decl;
17346 /* Substitute into the template parameters to obtain the real
17347 innermost set of parameters. This step is important if the
17348 innermost set of template parameters contains value
17349 parameters whose types depend on outer template parameters. */
17350 TREE_VEC_LENGTH (partial_args)--;
17351 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
17353 flag_access_control = save_access_control;
17359 /* Return truthvalue if we're processing a template different from
17360 the last one involved in diagnostics. */
17362 problematic_instantiation_changed (void)
17364 return last_template_error_tick != tinst_level_tick;
17367 /* Remember current template involved in diagnostics. */
17369 record_last_problematic_instantiation (void)
17371 last_template_error_tick = tinst_level_tick;
17374 struct tinst_level *
17375 current_instantiation (void)
17377 return current_tinst_level;
17380 /* [temp.param] Check that template non-type parm TYPE is of an allowable
17381 type. Return zero for ok, nonzero for disallowed. Issue error and
17382 warning messages under control of COMPLAIN. */
17385 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
17387 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
17389 else if (POINTER_TYPE_P (type))
17391 else if (TYPE_PTR_TO_MEMBER_P (type))
17393 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
17395 else if (TREE_CODE (type) == TYPENAME_TYPE)
17398 if (complain & tf_error)
17399 error ("%q#T is not a valid type for a template constant parameter", type);
17403 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
17404 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
17407 dependent_type_p_r (tree type)
17413 A type is dependent if it is:
17415 -- a template parameter. Template template parameters are types
17416 for us (since TYPE_P holds true for them) so we handle
17418 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17419 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
17421 /* -- a qualified-id with a nested-name-specifier which contains a
17422 class-name that names a dependent type or whose unqualified-id
17423 names a dependent type. */
17424 if (TREE_CODE (type) == TYPENAME_TYPE)
17426 /* -- a cv-qualified type where the cv-unqualified type is
17428 type = TYPE_MAIN_VARIANT (type);
17429 /* -- a compound type constructed from any dependent type. */
17430 if (TYPE_PTR_TO_MEMBER_P (type))
17431 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
17432 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
17434 else if (TREE_CODE (type) == POINTER_TYPE
17435 || TREE_CODE (type) == REFERENCE_TYPE)
17436 return dependent_type_p (TREE_TYPE (type));
17437 else if (TREE_CODE (type) == FUNCTION_TYPE
17438 || TREE_CODE (type) == METHOD_TYPE)
17442 if (dependent_type_p (TREE_TYPE (type)))
17444 for (arg_type = TYPE_ARG_TYPES (type);
17446 arg_type = TREE_CHAIN (arg_type))
17447 if (dependent_type_p (TREE_VALUE (arg_type)))
17451 /* -- an array type constructed from any dependent type or whose
17452 size is specified by a constant expression that is
17453 value-dependent. */
17454 if (TREE_CODE (type) == ARRAY_TYPE)
17456 if (TYPE_DOMAIN (type)
17457 && dependent_type_p (TYPE_DOMAIN (type)))
17459 return dependent_type_p (TREE_TYPE (type));
17461 else if (TREE_CODE (type) == INTEGER_TYPE
17462 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
17464 /* If this is the TYPE_DOMAIN of an array type, consider it
17465 dependent. We already checked for value-dependence in
17466 compute_array_index_type. */
17467 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
17470 /* -- a template-id in which either the template name is a template
17472 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
17474 /* ... or any of the template arguments is a dependent type or
17475 an expression that is type-dependent or value-dependent. */
17476 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
17477 && (any_dependent_template_arguments_p
17478 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
17481 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
17482 argument of the `typeof' expression is not type-dependent, then
17483 it should already been have resolved. */
17484 if (TREE_CODE (type) == TYPEOF_TYPE
17485 || TREE_CODE (type) == DECLTYPE_TYPE)
17488 /* A template argument pack is dependent if any of its packed
17490 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
17492 tree args = ARGUMENT_PACK_ARGS (type);
17493 int i, len = TREE_VEC_LENGTH (args);
17494 for (i = 0; i < len; ++i)
17495 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17499 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17500 be template parameters. */
17501 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17504 /* The standard does not specifically mention types that are local
17505 to template functions or local classes, but they should be
17506 considered dependent too. For example:
17508 template <int I> void f() {
17513 The size of `E' cannot be known until the value of `I' has been
17514 determined. Therefore, `E' must be considered dependent. */
17515 scope = TYPE_CONTEXT (type);
17516 if (scope && TYPE_P (scope))
17517 return dependent_type_p (scope);
17518 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17519 return type_dependent_expression_p (scope);
17521 /* Other types are non-dependent. */
17525 /* Returns TRUE if TYPE is dependent, in the sense of
17526 [temp.dep.type]. */
17529 dependent_type_p (tree type)
17531 /* If there are no template parameters in scope, then there can't be
17532 any dependent types. */
17533 if (!processing_template_decl)
17535 /* If we are not processing a template, then nobody should be
17536 providing us with a dependent type. */
17538 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17542 /* If the type is NULL, we have not computed a type for the entity
17543 in question; in that case, the type is dependent. */
17547 /* Erroneous types can be considered non-dependent. */
17548 if (type == error_mark_node)
17551 /* If we have not already computed the appropriate value for TYPE,
17553 if (!TYPE_DEPENDENT_P_VALID (type))
17555 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17556 TYPE_DEPENDENT_P_VALID (type) = 1;
17559 return TYPE_DEPENDENT_P (type);
17562 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17563 lookup. In other words, a dependent type that is not the current
17567 dependent_scope_p (tree scope)
17569 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17570 && !currently_open_class (scope));
17573 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17574 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17578 value_dependent_expression_p (tree expression)
17580 if (!processing_template_decl)
17583 /* A name declared with a dependent type. */
17584 if (DECL_P (expression) && type_dependent_expression_p (expression))
17587 switch (TREE_CODE (expression))
17589 case IDENTIFIER_NODE:
17590 /* A name that has not been looked up -- must be dependent. */
17593 case TEMPLATE_PARM_INDEX:
17594 /* A non-type template parm. */
17598 /* A non-type template parm. */
17599 if (DECL_TEMPLATE_PARM_P (expression))
17601 return value_dependent_expression_p (DECL_INITIAL (expression));
17604 /* A constant with integral or enumeration type and is initialized
17605 with an expression that is value-dependent. */
17606 if (DECL_INITIAL (expression)
17607 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17608 && value_dependent_expression_p (DECL_INITIAL (expression)))
17612 case DYNAMIC_CAST_EXPR:
17613 case STATIC_CAST_EXPR:
17614 case CONST_CAST_EXPR:
17615 case REINTERPRET_CAST_EXPR:
17617 /* These expressions are value-dependent if the type to which
17618 the cast occurs is dependent or the expression being casted
17619 is value-dependent. */
17621 tree type = TREE_TYPE (expression);
17623 if (dependent_type_p (type))
17626 /* A functional cast has a list of operands. */
17627 expression = TREE_OPERAND (expression, 0);
17630 /* If there are no operands, it must be an expression such
17631 as "int()". This should not happen for aggregate types
17632 because it would form non-constant expressions. */
17633 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17638 if (TREE_CODE (expression) == TREE_LIST)
17639 return any_value_dependent_elements_p (expression);
17641 return value_dependent_expression_p (expression);
17646 /* A `sizeof' expression is value-dependent if the operand is
17647 type-dependent or is a pack expansion. */
17648 expression = TREE_OPERAND (expression, 0);
17649 if (PACK_EXPANSION_P (expression))
17651 else if (TYPE_P (expression))
17652 return dependent_type_p (expression);
17653 return type_dependent_expression_p (expression);
17655 case NOEXCEPT_EXPR:
17656 expression = TREE_OPERAND (expression, 0);
17657 /* FIXME why check value-dependency? */
17658 return (type_dependent_expression_p (expression)
17659 || value_dependent_expression_p (expression));
17663 tree name = TREE_OPERAND (expression, 1);
17664 return value_dependent_expression_p (name);
17667 case COMPONENT_REF:
17668 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17669 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17672 /* A CALL_EXPR may appear in a constant expression if it is a
17673 call to a builtin function, e.g., __builtin_constant_p. All
17674 such calls are value-dependent. */
17677 case NONTYPE_ARGUMENT_PACK:
17678 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17679 is value-dependent. */
17681 tree values = ARGUMENT_PACK_ARGS (expression);
17682 int i, len = TREE_VEC_LENGTH (values);
17684 for (i = 0; i < len; ++i)
17685 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17693 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17694 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17695 || (type2 ? dependent_type_p (type2) : false));
17699 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17700 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17704 tree op = TREE_OPERAND (expression, 0);
17705 return (value_dependent_expression_p (op)
17706 || has_value_dependent_address (op));
17710 /* A constant expression is value-dependent if any subexpression is
17711 value-dependent. */
17712 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17714 case tcc_reference:
17716 return (value_dependent_expression_p
17717 (TREE_OPERAND (expression, 0)));
17719 case tcc_comparison:
17721 return ((value_dependent_expression_p
17722 (TREE_OPERAND (expression, 0)))
17723 || (value_dependent_expression_p
17724 (TREE_OPERAND (expression, 1))));
17726 case tcc_expression:
17730 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17731 /* In some cases, some of the operands may be missing.
17732 (For example, in the case of PREDECREMENT_EXPR, the
17733 amount to increment by may be missing.) That doesn't
17734 make the expression dependent. */
17735 if (TREE_OPERAND (expression, i)
17736 && (value_dependent_expression_p
17737 (TREE_OPERAND (expression, i))))
17747 /* The expression is not value-dependent. */
17751 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17752 [temp.dep.expr]. */
17755 type_dependent_expression_p (tree expression)
17757 if (!processing_template_decl)
17760 if (expression == error_mark_node)
17763 /* An unresolved name is always dependent. */
17764 if (TREE_CODE (expression) == IDENTIFIER_NODE
17765 || TREE_CODE (expression) == USING_DECL)
17768 /* Some expression forms are never type-dependent. */
17769 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17770 || TREE_CODE (expression) == SIZEOF_EXPR
17771 || TREE_CODE (expression) == ALIGNOF_EXPR
17772 || TREE_CODE (expression) == NOEXCEPT_EXPR
17773 || TREE_CODE (expression) == TRAIT_EXPR
17774 || TREE_CODE (expression) == TYPEID_EXPR
17775 || TREE_CODE (expression) == DELETE_EXPR
17776 || TREE_CODE (expression) == VEC_DELETE_EXPR
17777 || TREE_CODE (expression) == THROW_EXPR)
17780 /* The types of these expressions depends only on the type to which
17781 the cast occurs. */
17782 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17783 || TREE_CODE (expression) == STATIC_CAST_EXPR
17784 || TREE_CODE (expression) == CONST_CAST_EXPR
17785 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17786 || TREE_CODE (expression) == CAST_EXPR)
17787 return dependent_type_p (TREE_TYPE (expression));
17789 /* The types of these expressions depends only on the type created
17790 by the expression. */
17791 if (TREE_CODE (expression) == NEW_EXPR
17792 || TREE_CODE (expression) == VEC_NEW_EXPR)
17794 /* For NEW_EXPR tree nodes created inside a template, either
17795 the object type itself or a TREE_LIST may appear as the
17797 tree type = TREE_OPERAND (expression, 1);
17798 if (TREE_CODE (type) == TREE_LIST)
17799 /* This is an array type. We need to check array dimensions
17801 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17802 || value_dependent_expression_p
17803 (TREE_OPERAND (TREE_VALUE (type), 1));
17805 return dependent_type_p (type);
17808 if (TREE_CODE (expression) == SCOPE_REF)
17810 tree scope = TREE_OPERAND (expression, 0);
17811 tree name = TREE_OPERAND (expression, 1);
17813 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
17814 contains an identifier associated by name lookup with one or more
17815 declarations declared with a dependent type, or...a
17816 nested-name-specifier or qualified-id that names a member of an
17817 unknown specialization. */
17818 return (type_dependent_expression_p (name)
17819 || dependent_scope_p (scope));
17822 if (TREE_CODE (expression) == FUNCTION_DECL
17823 && DECL_LANG_SPECIFIC (expression)
17824 && DECL_TEMPLATE_INFO (expression)
17825 && (any_dependent_template_arguments_p
17826 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17829 if (TREE_CODE (expression) == TEMPLATE_DECL
17830 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17833 if (TREE_CODE (expression) == STMT_EXPR)
17834 expression = stmt_expr_value_expr (expression);
17836 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17841 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17843 if (type_dependent_expression_p (elt))
17849 /* A static data member of the current instantiation with incomplete
17850 array type is type-dependent, as the definition and specializations
17851 can have different bounds. */
17852 if (TREE_CODE (expression) == VAR_DECL
17853 && DECL_CLASS_SCOPE_P (expression)
17854 && dependent_type_p (DECL_CONTEXT (expression))
17855 && VAR_HAD_UNKNOWN_BOUND (expression))
17858 if (TREE_TYPE (expression) == unknown_type_node)
17860 if (TREE_CODE (expression) == ADDR_EXPR)
17861 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17862 if (TREE_CODE (expression) == COMPONENT_REF
17863 || TREE_CODE (expression) == OFFSET_REF)
17865 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17867 expression = TREE_OPERAND (expression, 1);
17868 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17871 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17872 if (TREE_CODE (expression) == SCOPE_REF)
17875 if (TREE_CODE (expression) == BASELINK)
17876 expression = BASELINK_FUNCTIONS (expression);
17878 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17880 if (any_dependent_template_arguments_p
17881 (TREE_OPERAND (expression, 1)))
17883 expression = TREE_OPERAND (expression, 0);
17885 gcc_assert (TREE_CODE (expression) == OVERLOAD
17886 || TREE_CODE (expression) == FUNCTION_DECL);
17890 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17892 expression = OVL_NEXT (expression);
17897 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17899 return (dependent_type_p (TREE_TYPE (expression)));
17902 /* Like type_dependent_expression_p, but it also works while not processing
17903 a template definition, i.e. during substitution or mangling. */
17906 type_dependent_expression_p_push (tree expr)
17909 ++processing_template_decl;
17910 b = type_dependent_expression_p (expr);
17911 --processing_template_decl;
17915 /* Returns TRUE if ARGS contains a type-dependent expression. */
17918 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17923 FOR_EACH_VEC_ELT (tree, args, i, arg)
17925 if (type_dependent_expression_p (arg))
17931 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17932 expressions) contains any value-dependent expressions. */
17935 any_value_dependent_elements_p (const_tree list)
17937 for (; list; list = TREE_CHAIN (list))
17938 if (value_dependent_expression_p (TREE_VALUE (list)))
17944 /* Returns TRUE if the ARG (a template argument) is dependent. */
17947 dependent_template_arg_p (tree arg)
17949 if (!processing_template_decl)
17952 if (TREE_CODE (arg) == TEMPLATE_DECL
17953 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17954 return dependent_template_p (arg);
17955 else if (ARGUMENT_PACK_P (arg))
17957 tree args = ARGUMENT_PACK_ARGS (arg);
17958 int i, len = TREE_VEC_LENGTH (args);
17959 for (i = 0; i < len; ++i)
17961 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17967 else if (TYPE_P (arg))
17968 return dependent_type_p (arg);
17970 return (type_dependent_expression_p (arg)
17971 || value_dependent_expression_p (arg));
17974 /* Returns true if ARGS (a collection of template arguments) contains
17975 any types that require structural equality testing. */
17978 any_template_arguments_need_structural_equality_p (tree args)
17985 if (args == error_mark_node)
17988 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17990 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17991 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17993 tree arg = TREE_VEC_ELT (level, j);
17994 tree packed_args = NULL_TREE;
17997 if (ARGUMENT_PACK_P (arg))
17999 /* Look inside the argument pack. */
18000 packed_args = ARGUMENT_PACK_ARGS (arg);
18001 len = TREE_VEC_LENGTH (packed_args);
18004 for (k = 0; k < len; ++k)
18007 arg = TREE_VEC_ELT (packed_args, k);
18009 if (error_operand_p (arg))
18011 else if (TREE_CODE (arg) == TEMPLATE_DECL
18012 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18014 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18016 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18017 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18026 /* Returns true if ARGS (a collection of template arguments) contains
18027 any dependent arguments. */
18030 any_dependent_template_arguments_p (const_tree args)
18037 if (args == error_mark_node)
18040 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18042 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18043 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18044 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18051 /* Returns TRUE if the template TMPL is dependent. */
18054 dependent_template_p (tree tmpl)
18056 if (TREE_CODE (tmpl) == OVERLOAD)
18060 if (dependent_template_p (OVL_FUNCTION (tmpl)))
18062 tmpl = OVL_CHAIN (tmpl);
18067 /* Template template parameters are dependent. */
18068 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18069 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18071 /* So are names that have not been looked up. */
18072 if (TREE_CODE (tmpl) == SCOPE_REF
18073 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18075 /* So are member templates of dependent classes. */
18076 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18077 return dependent_type_p (DECL_CONTEXT (tmpl));
18081 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18084 dependent_template_id_p (tree tmpl, tree args)
18086 return (dependent_template_p (tmpl)
18087 || any_dependent_template_arguments_p (args));
18090 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18094 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18098 if (!processing_template_decl)
18101 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18103 tree decl = TREE_VEC_ELT (declv, i);
18104 tree init = TREE_VEC_ELT (initv, i);
18105 tree cond = TREE_VEC_ELT (condv, i);
18106 tree incr = TREE_VEC_ELT (incrv, i);
18108 if (type_dependent_expression_p (decl))
18111 if (init && type_dependent_expression_p (init))
18114 if (type_dependent_expression_p (cond))
18117 if (COMPARISON_CLASS_P (cond)
18118 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18119 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18122 if (TREE_CODE (incr) == MODOP_EXPR)
18124 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18125 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18128 else if (type_dependent_expression_p (incr))
18130 else if (TREE_CODE (incr) == MODIFY_EXPR)
18132 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18134 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
18136 tree t = TREE_OPERAND (incr, 1);
18137 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
18138 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
18147 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
18148 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
18149 no such TYPE can be found. Note that this function peers inside
18150 uninstantiated templates and therefore should be used only in
18151 extremely limited situations. ONLY_CURRENT_P restricts this
18152 peering to the currently open classes hierarchy (which is required
18153 when comparing types). */
18156 resolve_typename_type (tree type, bool only_current_p)
18165 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
18167 scope = TYPE_CONTEXT (type);
18168 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
18169 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
18170 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
18171 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
18172 identifier of the TYPENAME_TYPE anymore.
18173 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
18174 TYPENAME_TYPE instead, we avoid messing up with a possible
18175 typedef variant case. */
18176 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
18178 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
18179 it first before we can figure out what NAME refers to. */
18180 if (TREE_CODE (scope) == TYPENAME_TYPE)
18181 scope = resolve_typename_type (scope, only_current_p);
18182 /* If we don't know what SCOPE refers to, then we cannot resolve the
18184 if (TREE_CODE (scope) == TYPENAME_TYPE)
18186 /* If the SCOPE is a template type parameter, we have no way of
18187 resolving the name. */
18188 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
18190 /* If the SCOPE is not the current instantiation, there's no reason
18191 to look inside it. */
18192 if (only_current_p && !currently_open_class (scope))
18194 /* If this is a typedef, we don't want to look inside (c++/11987). */
18195 if (typedef_variant_p (type))
18197 /* If SCOPE isn't the template itself, it will not have a valid
18198 TYPE_FIELDS list. */
18199 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
18200 /* scope is either the template itself or a compatible instantiation
18201 like X<T>, so look up the name in the original template. */
18202 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
18204 /* scope is a partial instantiation, so we can't do the lookup or we
18205 will lose the template arguments. */
18207 /* Enter the SCOPE so that name lookup will be resolved as if we
18208 were in the class definition. In particular, SCOPE will no
18209 longer be considered a dependent type. */
18210 pushed_scope = push_scope (scope);
18211 /* Look up the declaration. */
18212 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
18214 result = NULL_TREE;
18216 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
18217 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
18220 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
18221 && TREE_CODE (decl) == TYPE_DECL)
18223 result = TREE_TYPE (decl);
18224 if (result == error_mark_node)
18225 result = NULL_TREE;
18227 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
18228 && DECL_CLASS_TEMPLATE_P (decl))
18232 /* Obtain the template and the arguments. */
18233 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
18234 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
18235 /* Instantiate the template. */
18236 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
18237 /*entering_scope=*/0,
18238 tf_error | tf_user);
18239 if (result == error_mark_node)
18240 result = NULL_TREE;
18243 /* Leave the SCOPE. */
18245 pop_scope (pushed_scope);
18247 /* If we failed to resolve it, return the original typename. */
18251 /* If lookup found a typename type, resolve that too. */
18252 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
18254 /* Ill-formed programs can cause infinite recursion here, so we
18255 must catch that. */
18256 TYPENAME_IS_RESOLVING_P (type) = 1;
18257 result = resolve_typename_type (result, only_current_p);
18258 TYPENAME_IS_RESOLVING_P (type) = 0;
18261 /* Qualify the resulting type. */
18262 quals = cp_type_quals (type);
18264 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
18269 /* EXPR is an expression which is not type-dependent. Return a proxy
18270 for EXPR that can be used to compute the types of larger
18271 expressions containing EXPR. */
18274 build_non_dependent_expr (tree expr)
18278 /* Preserve null pointer constants so that the type of things like
18279 "p == 0" where "p" is a pointer can be determined. */
18280 if (null_ptr_cst_p (expr))
18282 /* Preserve OVERLOADs; the functions must be available to resolve
18285 if (TREE_CODE (inner_expr) == STMT_EXPR)
18286 inner_expr = stmt_expr_value_expr (inner_expr);
18287 if (TREE_CODE (inner_expr) == ADDR_EXPR)
18288 inner_expr = TREE_OPERAND (inner_expr, 0);
18289 if (TREE_CODE (inner_expr) == COMPONENT_REF)
18290 inner_expr = TREE_OPERAND (inner_expr, 1);
18291 if (is_overloaded_fn (inner_expr)
18292 || TREE_CODE (inner_expr) == OFFSET_REF)
18294 /* There is no need to return a proxy for a variable. */
18295 if (TREE_CODE (expr) == VAR_DECL)
18297 /* Preserve string constants; conversions from string constants to
18298 "char *" are allowed, even though normally a "const char *"
18299 cannot be used to initialize a "char *". */
18300 if (TREE_CODE (expr) == STRING_CST)
18302 /* Preserve arithmetic constants, as an optimization -- there is no
18303 reason to create a new node. */
18304 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
18306 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
18307 There is at least one place where we want to know that a
18308 particular expression is a throw-expression: when checking a ?:
18309 expression, there are special rules if the second or third
18310 argument is a throw-expression. */
18311 if (TREE_CODE (expr) == THROW_EXPR)
18314 if (TREE_CODE (expr) == COND_EXPR)
18315 return build3 (COND_EXPR,
18317 TREE_OPERAND (expr, 0),
18318 (TREE_OPERAND (expr, 1)
18319 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
18320 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
18321 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
18322 if (TREE_CODE (expr) == COMPOUND_EXPR
18323 && !COMPOUND_EXPR_OVERLOADED (expr))
18324 return build2 (COMPOUND_EXPR,
18326 TREE_OPERAND (expr, 0),
18327 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
18329 /* If the type is unknown, it can't really be non-dependent */
18330 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
18332 /* Otherwise, build a NON_DEPENDENT_EXPR.
18334 REFERENCE_TYPEs are not stripped for expressions in templates
18335 because doing so would play havoc with mangling. Consider, for
18338 template <typename T> void f<T& g>() { g(); }
18340 In the body of "f", the expression for "g" will have
18341 REFERENCE_TYPE, even though the standard says that it should
18342 not. The reason is that we must preserve the syntactic form of
18343 the expression so that mangling (say) "f<g>" inside the body of
18344 "f" works out correctly. Therefore, the REFERENCE_TYPE is
18346 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
18349 /* ARGS is a vector of expressions as arguments to a function call.
18350 Replace the arguments with equivalent non-dependent expressions.
18351 This modifies ARGS in place. */
18354 make_args_non_dependent (VEC(tree,gc) *args)
18359 FOR_EACH_VEC_ELT (tree, args, ix, arg)
18361 tree newarg = build_non_dependent_expr (arg);
18363 VEC_replace (tree, args, ix, newarg);
18367 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
18368 with a level one deeper than the actual template parms. */
18373 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
18374 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
18375 TYPE_DECL, get_identifier ("auto"), au);
18376 TYPE_STUB_DECL (au) = TYPE_NAME (au);
18377 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
18378 (0, processing_template_decl + 1, processing_template_decl + 1,
18379 TYPE_NAME (au), NULL_TREE);
18380 TYPE_CANONICAL (au) = canonical_type_parameter (au);
18381 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
18382 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
18387 /* Given type ARG, return std::initializer_list<ARG>. */
18392 tree std_init_list = namespace_binding
18393 (get_identifier ("initializer_list"), std_node);
18395 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
18397 error ("deducing from brace-enclosed initializer list requires "
18398 "#include <initializer_list>");
18399 return error_mark_node;
18401 argvec = make_tree_vec (1);
18402 TREE_VEC_ELT (argvec, 0) = arg;
18403 return lookup_template_class (std_init_list, argvec, NULL_TREE,
18404 NULL_TREE, 0, tf_warning_or_error);
18407 /* Replace auto in TYPE with std::initializer_list<auto>. */
18410 listify_autos (tree type, tree auto_node)
18412 tree init_auto = listify (auto_node);
18413 tree argvec = make_tree_vec (1);
18414 TREE_VEC_ELT (argvec, 0) = init_auto;
18415 if (processing_template_decl)
18416 argvec = add_to_template_args (current_template_args (), argvec);
18417 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18420 /* walk_tree helper for do_auto_deduction. */
18423 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
18426 /* Is this a variable with the type we're looking for? */
18428 && TREE_TYPE (*tp) == type)
18434 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
18435 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
18438 do_auto_deduction (tree type, tree init, tree auto_node)
18440 tree parms, tparms, targs;
18445 /* The name of the object being declared shall not appear in the
18446 initializer expression. */
18447 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
18450 error ("variable %q#D with %<auto%> type used in its own "
18451 "initializer", decl);
18452 return error_mark_node;
18455 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
18456 with either a new invented type template parameter U or, if the
18457 initializer is a braced-init-list (8.5.4), with
18458 std::initializer_list<U>. */
18459 if (BRACE_ENCLOSED_INITIALIZER_P (init))
18460 type = listify_autos (type, auto_node);
18462 parms = build_tree_list (NULL_TREE, type);
18464 tparms = make_tree_vec (1);
18465 targs = make_tree_vec (1);
18466 TREE_VEC_ELT (tparms, 0)
18467 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
18468 val = type_unification_real (tparms, targs, parms, args, 1, 0,
18469 DEDUCE_CALL, LOOKUP_NORMAL);
18472 error ("unable to deduce %qT from %qE", type, init);
18473 return error_mark_node;
18476 /* If the list of declarators contains more than one declarator, the type
18477 of each declared variable is determined as described above. If the
18478 type deduced for the template parameter U is not the same in each
18479 deduction, the program is ill-formed. */
18480 if (TREE_TYPE (auto_node)
18481 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
18483 error ("inconsistent deduction for %qT: %qT and then %qT",
18484 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
18485 return error_mark_node;
18487 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
18489 if (processing_template_decl)
18490 targs = add_to_template_args (current_template_args (), targs);
18491 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
18494 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
18498 splice_late_return_type (tree type, tree late_return_type)
18502 if (late_return_type == NULL_TREE)
18504 argvec = make_tree_vec (1);
18505 TREE_VEC_ELT (argvec, 0) = late_return_type;
18506 if (processing_template_decl)
18507 argvec = add_to_template_args (current_template_args (), argvec);
18508 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18511 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
18514 is_auto (const_tree type)
18516 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18517 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
18523 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
18524 appear as a type-specifier for the declaration in question, we don't
18525 have to look through the whole type. */
18528 type_uses_auto (tree type)
18530 enum tree_code code;
18531 if (is_auto (type))
18534 code = TREE_CODE (type);
18536 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18537 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18538 || code == METHOD_TYPE || code == ARRAY_TYPE)
18539 return type_uses_auto (TREE_TYPE (type));
18541 if (TYPE_PTRMEMFUNC_P (type))
18542 return type_uses_auto (TREE_TYPE (TREE_TYPE
18543 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18548 /* For a given template T, return the vector of typedefs referenced
18549 in T for which access check is needed at T instantiation time.
18550 T is either a FUNCTION_DECL or a RECORD_TYPE.
18551 Those typedefs were added to T by the function
18552 append_type_to_template_for_access_check. */
18554 VEC(qualified_typedef_usage_t,gc)*
18555 get_types_needing_access_check (tree t)
18558 VEC(qualified_typedef_usage_t,gc) *result = NULL;
18560 if (!t || t == error_mark_node)
18563 if (!(ti = get_template_info (t)))
18566 if (CLASS_TYPE_P (t)
18567 || TREE_CODE (t) == FUNCTION_DECL)
18569 if (!TI_TEMPLATE (ti))
18572 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
18578 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
18579 tied to T. That list of typedefs will be access checked at
18580 T instantiation time.
18581 T is either a FUNCTION_DECL or a RECORD_TYPE.
18582 TYPE_DECL is a TYPE_DECL node representing a typedef.
18583 SCOPE is the scope through which TYPE_DECL is accessed.
18584 LOCATION is the location of the usage point of TYPE_DECL.
18586 This function is a subroutine of
18587 append_type_to_template_for_access_check. */
18590 append_type_to_template_for_access_check_1 (tree t,
18593 location_t location)
18595 qualified_typedef_usage_t typedef_usage;
18598 if (!t || t == error_mark_node)
18601 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
18602 || CLASS_TYPE_P (t))
18604 && TREE_CODE (type_decl) == TYPE_DECL
18607 if (!(ti = get_template_info (t)))
18610 gcc_assert (TI_TEMPLATE (ti));
18612 typedef_usage.typedef_decl = type_decl;
18613 typedef_usage.context = scope;
18614 typedef_usage.locus = location;
18616 VEC_safe_push (qualified_typedef_usage_t, gc,
18617 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
18621 /* Append TYPE_DECL to the template TEMPL.
18622 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
18623 At TEMPL instanciation time, TYPE_DECL will be checked to see
18624 if it can be accessed through SCOPE.
18625 LOCATION is the location of the usage point of TYPE_DECL.
18627 e.g. consider the following code snippet:
18634 template<class U> struct S
18636 C::myint mi; // <-- usage point of the typedef C::myint
18641 At S<char> instantiation time, we need to check the access of C::myint
18642 In other words, we need to check the access of the myint typedef through
18643 the C scope. For that purpose, this function will add the myint typedef
18644 and the scope C through which its being accessed to a list of typedefs
18645 tied to the template S. That list will be walked at template instantiation
18646 time and access check performed on each typedefs it contains.
18647 Note that this particular code snippet should yield an error because
18648 myint is private to C. */
18651 append_type_to_template_for_access_check (tree templ,
18654 location_t location)
18656 qualified_typedef_usage_t *iter;
18659 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
18661 /* Make sure we don't append the type to the template twice. */
18662 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
18663 get_types_needing_access_check (templ),
18665 if (iter->typedef_decl == type_decl && scope == iter->context)
18668 append_type_to_template_for_access_check_1 (templ, type_decl,
18672 /* Set up the hash tables for template instantiations. */
18675 init_template_processing (void)
18677 decl_specializations = htab_create_ggc (37,
18678 hash_specialization,
18679 eq_specializations,
18681 type_specializations = htab_create_ggc (37,
18682 hash_specialization,
18683 eq_specializations,
18687 /* Print stats about the template hash tables for -fstats. */
18690 print_template_statistics (void)
18692 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
18693 "%f collisions\n", (long) htab_size (decl_specializations),
18694 (long) htab_elements (decl_specializations),
18695 htab_collisions (decl_specializations));
18696 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
18697 "%f collisions\n", (long) htab_size (type_specializations),
18698 (long) htab_elements (type_specializations),
18699 htab_collisions (type_specializations));
18702 #include "gt-cp-pt.h"