1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 static void push_access_scope (tree);
113 static void pop_access_scope (tree);
114 static bool resolve_overloaded_unification (tree, tree, tree, tree,
115 unification_kind_t, int);
116 static int try_one_overload (tree, tree, tree, tree, tree,
117 unification_kind_t, int, bool);
118 static int unify (tree, tree, tree, tree, int);
119 static void add_pending_template (tree);
120 static tree reopen_tinst_level (struct tinst_level *);
121 static tree tsubst_initializer_list (tree, tree);
122 static tree get_class_bindings (tree, tree, tree);
123 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
125 static void tsubst_enum (tree, tree, tree);
126 static tree add_to_template_args (tree, tree);
127 static tree add_outermost_template_args (tree, tree);
128 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
129 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
131 static int type_unification_real (tree, tree, tree, const tree *,
132 unsigned int, int, unification_kind_t, int);
133 static void note_template_header (int);
134 static tree convert_nontype_argument_function (tree, tree);
135 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
136 static tree convert_template_argument (tree, tree, tree,
137 tsubst_flags_t, int, tree);
138 static int for_each_template_parm (tree, tree_fn_t, void*,
139 struct pointer_set_t*, bool);
140 static tree expand_template_argument_pack (tree);
141 static tree build_template_parm_index (int, int, int, int, tree, tree);
142 static bool inline_needs_template_parms (tree);
143 static void push_inline_template_parms_recursive (tree, int);
144 static tree retrieve_local_specialization (tree);
145 static void register_local_specialization (tree, tree);
146 static hashval_t hash_specialization (const void *p);
147 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
148 static int mark_template_parm (tree, void *);
149 static int template_parm_this_level_p (tree, void *);
150 static tree tsubst_friend_function (tree, tree);
151 static tree tsubst_friend_class (tree, tree);
152 static int can_complete_type_without_circularity (tree);
153 static tree get_bindings (tree, tree, tree, bool);
154 static int template_decl_level (tree);
155 static int check_cv_quals_for_unify (int, tree, tree);
156 static void template_parm_level_and_index (tree, int*, int*);
157 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
158 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
159 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
160 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
161 static void regenerate_decl_from_template (tree, tree);
162 static tree most_specialized_class (tree, tree, tsubst_flags_t);
163 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
164 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
166 static bool check_specialization_scope (void);
167 static tree process_partial_specialization (tree);
168 static void set_current_access_from_decl (tree);
169 static tree get_template_base (tree, tree, tree, tree);
170 static tree try_class_unification (tree, tree, tree, tree);
171 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
173 static bool template_template_parm_bindings_ok_p (tree, tree);
174 static int template_args_equal (tree, tree);
175 static void tsubst_default_arguments (tree);
176 static tree for_each_template_parm_r (tree *, int *, void *);
177 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
178 static void copy_default_args_to_explicit_spec (tree);
179 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
180 static int eq_local_specializations (const void *, const void *);
181 static bool dependent_template_arg_p (tree);
182 static bool any_template_arguments_need_structural_equality_p (tree);
183 static bool dependent_type_p_r (tree);
184 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
185 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
186 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
187 static tree tsubst_decl (tree, tree, tsubst_flags_t);
188 static void perform_typedefs_access_check (tree tmpl, tree targs);
189 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
191 static tree listify (tree);
192 static tree listify_autos (tree, tree);
193 static tree template_parm_to_arg (tree t);
194 static tree current_template_args (void);
195 static tree fixup_template_type_parm_type (tree, int);
196 static tree fixup_template_parm_index (tree, tree, int);
197 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
199 /* Make the current scope suitable for access checking when we are
200 processing T. T can be FUNCTION_DECL for instantiated function
201 template, or VAR_DECL for static member variable (need by
202 instantiate_decl). */
205 push_access_scope (tree t)
207 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
208 || TREE_CODE (t) == VAR_DECL);
210 if (DECL_FRIEND_CONTEXT (t))
211 push_nested_class (DECL_FRIEND_CONTEXT (t));
212 else if (DECL_CLASS_SCOPE_P (t))
213 push_nested_class (DECL_CONTEXT (t));
215 push_to_top_level ();
217 if (TREE_CODE (t) == FUNCTION_DECL)
219 saved_access_scope = tree_cons
220 (NULL_TREE, current_function_decl, saved_access_scope);
221 current_function_decl = t;
225 /* Restore the scope set up by push_access_scope. T is the node we
229 pop_access_scope (tree t)
231 if (TREE_CODE (t) == FUNCTION_DECL)
233 current_function_decl = TREE_VALUE (saved_access_scope);
234 saved_access_scope = TREE_CHAIN (saved_access_scope);
237 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
240 pop_from_top_level ();
243 /* Do any processing required when DECL (a member template
244 declaration) is finished. Returns the TEMPLATE_DECL corresponding
245 to DECL, unless it is a specialization, in which case the DECL
246 itself is returned. */
249 finish_member_template_decl (tree decl)
251 if (decl == error_mark_node)
252 return error_mark_node;
254 gcc_assert (DECL_P (decl));
256 if (TREE_CODE (decl) == TYPE_DECL)
260 type = TREE_TYPE (decl);
261 if (type == error_mark_node)
262 return error_mark_node;
263 if (MAYBE_CLASS_TYPE_P (type)
264 && CLASSTYPE_TEMPLATE_INFO (type)
265 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
267 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
268 check_member_template (tmpl);
273 else if (TREE_CODE (decl) == FIELD_DECL)
274 error ("data member %qD cannot be a member template", decl);
275 else if (DECL_TEMPLATE_INFO (decl))
277 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
279 check_member_template (DECL_TI_TEMPLATE (decl));
280 return DECL_TI_TEMPLATE (decl);
286 error ("invalid member template declaration %qD", decl);
288 return error_mark_node;
291 /* Create a template info node. */
294 build_template_info (tree template_decl, tree template_args)
296 tree result = make_node (TEMPLATE_INFO);
297 TI_TEMPLATE (result) = template_decl;
298 TI_ARGS (result) = template_args;
302 /* Return the template info node corresponding to T, whatever T is. */
305 get_template_info (const_tree t)
307 tree tinfo = NULL_TREE;
309 if (!t || t == error_mark_node)
312 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
313 tinfo = DECL_TEMPLATE_INFO (t);
315 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
318 if (TAGGED_TYPE_P (t))
319 tinfo = TYPE_TEMPLATE_INFO (t);
320 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
321 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
326 /* Returns the template nesting level of the indicated class TYPE.
336 A<T>::B<U> has depth two, while A<T> has depth one.
337 Both A<T>::B<int> and A<int>::B<U> have depth one, if
338 they are instantiations, not specializations.
340 This function is guaranteed to return 0 if passed NULL_TREE so
341 that, for example, `template_class_depth (current_class_type)' is
345 template_class_depth (tree type)
350 type && TREE_CODE (type) != NAMESPACE_DECL;
351 type = (TREE_CODE (type) == FUNCTION_DECL)
352 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
354 tree tinfo = get_template_info (type);
356 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
357 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
364 /* Subroutine of maybe_begin_member_template_processing.
365 Returns true if processing DECL needs us to push template parms. */
368 inline_needs_template_parms (tree decl)
370 if (! DECL_TEMPLATE_INFO (decl))
373 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
374 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
377 /* Subroutine of maybe_begin_member_template_processing.
378 Push the template parms in PARMS, starting from LEVELS steps into the
379 chain, and ending at the beginning, since template parms are listed
383 push_inline_template_parms_recursive (tree parmlist, int levels)
385 tree parms = TREE_VALUE (parmlist);
389 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
391 ++processing_template_decl;
392 current_template_parms
393 = tree_cons (size_int (processing_template_decl),
394 parms, current_template_parms);
395 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
397 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
399 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
401 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
403 if (parm == error_mark_node)
406 gcc_assert (DECL_P (parm));
408 switch (TREE_CODE (parm))
417 /* Make a CONST_DECL as is done in process_template_parm.
418 It is ugly that we recreate this here; the original
419 version built in process_template_parm is no longer
421 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
422 CONST_DECL, DECL_NAME (parm),
424 DECL_ARTIFICIAL (decl) = 1;
425 TREE_CONSTANT (decl) = 1;
426 TREE_READONLY (decl) = 1;
427 DECL_INITIAL (decl) = DECL_INITIAL (parm);
428 SET_DECL_TEMPLATE_PARM_P (decl);
439 /* Restore the template parameter context for a member template or
440 a friend template defined in a class definition. */
443 maybe_begin_member_template_processing (tree decl)
448 if (inline_needs_template_parms (decl))
450 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
451 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
453 if (DECL_TEMPLATE_SPECIALIZATION (decl))
456 parms = TREE_CHAIN (parms);
459 push_inline_template_parms_recursive (parms, levels);
462 /* Remember how many levels of template parameters we pushed so that
463 we can pop them later. */
464 VEC_safe_push (int, heap, inline_parm_levels, levels);
467 /* Undo the effects of maybe_begin_member_template_processing. */
470 maybe_end_member_template_processing (void)
475 if (VEC_length (int, inline_parm_levels) == 0)
478 last = VEC_pop (int, inline_parm_levels);
479 for (i = 0; i < last; ++i)
481 --processing_template_decl;
482 current_template_parms = TREE_CHAIN (current_template_parms);
487 /* Return a new template argument vector which contains all of ARGS,
488 but has as its innermost set of arguments the EXTRA_ARGS. */
491 add_to_template_args (tree args, tree extra_args)
498 if (args == NULL_TREE || extra_args == error_mark_node)
501 extra_depth = TMPL_ARGS_DEPTH (extra_args);
502 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
504 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
505 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
507 for (j = 1; j <= extra_depth; ++j, ++i)
508 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
513 /* Like add_to_template_args, but only the outermost ARGS are added to
514 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
515 (EXTRA_ARGS) levels are added. This function is used to combine
516 the template arguments from a partial instantiation with the
517 template arguments used to attain the full instantiation from the
518 partial instantiation. */
521 add_outermost_template_args (tree args, tree extra_args)
525 /* If there are more levels of EXTRA_ARGS than there are ARGS,
526 something very fishy is going on. */
527 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
529 /* If *all* the new arguments will be the EXTRA_ARGS, just return
531 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
534 /* For the moment, we make ARGS look like it contains fewer levels. */
535 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
537 new_args = add_to_template_args (args, extra_args);
539 /* Now, we restore ARGS to its full dimensions. */
540 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
545 /* Return the N levels of innermost template arguments from the ARGS. */
548 get_innermost_template_args (tree args, int n)
556 /* If N is 1, just return the innermost set of template arguments. */
558 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
560 /* If we're not removing anything, just return the arguments we were
562 extra_levels = TMPL_ARGS_DEPTH (args) - n;
563 gcc_assert (extra_levels >= 0);
564 if (extra_levels == 0)
567 /* Make a new set of arguments, not containing the outer arguments. */
568 new_args = make_tree_vec (n);
569 for (i = 1; i <= n; ++i)
570 SET_TMPL_ARGS_LEVEL (new_args, i,
571 TMPL_ARGS_LEVEL (args, i + extra_levels));
576 /* The inverse of get_innermost_template_args: Return all but the innermost
577 EXTRA_LEVELS levels of template arguments from the ARGS. */
580 strip_innermost_template_args (tree args, int extra_levels)
583 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
588 /* If N is 1, just return the outermost set of template arguments. */
590 return TMPL_ARGS_LEVEL (args, 1);
592 /* If we're not removing anything, just return the arguments we were
594 gcc_assert (extra_levels >= 0);
595 if (extra_levels == 0)
598 /* Make a new set of arguments, not containing the inner arguments. */
599 new_args = make_tree_vec (n);
600 for (i = 1; i <= n; ++i)
601 SET_TMPL_ARGS_LEVEL (new_args, i,
602 TMPL_ARGS_LEVEL (args, i));
607 /* We've got a template header coming up; push to a new level for storing
611 begin_template_parm_list (void)
613 /* We use a non-tag-transparent scope here, which causes pushtag to
614 put tags in this scope, rather than in the enclosing class or
615 namespace scope. This is the right thing, since we want
616 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
617 global template class, push_template_decl handles putting the
618 TEMPLATE_DECL into top-level scope. For a nested template class,
621 template <class T> struct S1 {
622 template <class T> struct S2 {};
625 pushtag contains special code to call pushdecl_with_scope on the
626 TEMPLATE_DECL for S2. */
627 begin_scope (sk_template_parms, NULL);
628 ++processing_template_decl;
629 ++processing_template_parmlist;
630 note_template_header (0);
633 /* This routine is called when a specialization is declared. If it is
634 invalid to declare a specialization here, an error is reported and
635 false is returned, otherwise this routine will return true. */
638 check_specialization_scope (void)
640 tree scope = current_scope ();
644 An explicit specialization shall be declared in the namespace of
645 which the template is a member, or, for member templates, in the
646 namespace of which the enclosing class or enclosing class
647 template is a member. An explicit specialization of a member
648 function, member class or static data member of a class template
649 shall be declared in the namespace of which the class template
651 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
653 error ("explicit specialization in non-namespace scope %qD", scope);
659 In an explicit specialization declaration for a member of a class
660 template or a member template that appears in namespace scope,
661 the member template and some of its enclosing class templates may
662 remain unspecialized, except that the declaration shall not
663 explicitly specialize a class member template if its enclosing
664 class templates are not explicitly specialized as well. */
665 if (current_template_parms)
667 error ("enclosing class templates are not explicitly specialized");
674 /* We've just seen template <>. */
677 begin_specialization (void)
679 begin_scope (sk_template_spec, NULL);
680 note_template_header (1);
681 return check_specialization_scope ();
684 /* Called at then end of processing a declaration preceded by
688 end_specialization (void)
691 reset_specialization ();
694 /* Any template <>'s that we have seen thus far are not referring to a
695 function specialization. */
698 reset_specialization (void)
700 processing_specialization = 0;
701 template_header_count = 0;
704 /* We've just seen a template header. If SPECIALIZATION is nonzero,
705 it was of the form template <>. */
708 note_template_header (int specialization)
710 processing_specialization = specialization;
711 template_header_count++;
714 /* We're beginning an explicit instantiation. */
717 begin_explicit_instantiation (void)
719 gcc_assert (!processing_explicit_instantiation);
720 processing_explicit_instantiation = true;
725 end_explicit_instantiation (void)
727 gcc_assert (processing_explicit_instantiation);
728 processing_explicit_instantiation = false;
731 /* An explicit specialization or partial specialization TMPL is being
732 declared. Check that the namespace in which the specialization is
733 occurring is permissible. Returns false iff it is invalid to
734 specialize TMPL in the current namespace. */
737 check_specialization_namespace (tree tmpl)
739 tree tpl_ns = decl_namespace_context (tmpl);
743 An explicit specialization shall be declared in the namespace of
744 which the template is a member, or, for member templates, in the
745 namespace of which the enclosing class or enclosing class
746 template is a member. An explicit specialization of a member
747 function, member class or static data member of a class template
748 shall be declared in the namespace of which the class template is
750 if (current_scope() != DECL_CONTEXT (tmpl)
751 && !at_namespace_scope_p ())
753 error ("specialization of %qD must appear at namespace scope", tmpl);
756 if (is_associated_namespace (current_namespace, tpl_ns))
757 /* Same or super-using namespace. */
761 permerror (input_location, "specialization of %qD in different namespace", tmpl);
762 permerror (input_location, " from definition of %q+#D", tmpl);
767 /* SPEC is an explicit instantiation. Check that it is valid to
768 perform this explicit instantiation in the current namespace. */
771 check_explicit_instantiation_namespace (tree spec)
775 /* DR 275: An explicit instantiation shall appear in an enclosing
776 namespace of its template. */
777 ns = decl_namespace_context (spec);
778 if (!is_ancestor (current_namespace, ns))
779 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
780 "(which does not enclose namespace %qD)",
781 spec, current_namespace, ns);
784 /* The TYPE is being declared. If it is a template type, that means it
785 is a partial specialization. Do appropriate error-checking. */
788 maybe_process_partial_specialization (tree type)
792 if (type == error_mark_node)
793 return error_mark_node;
795 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
797 error ("name of class shadows template template parameter %qD",
799 return error_mark_node;
802 context = TYPE_CONTEXT (type);
804 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
806 /* This is for ordinary explicit specialization and partial
807 specialization of a template class such as:
809 template <> class C<int>;
813 template <class T> class C<T*>;
815 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
817 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
818 && !COMPLETE_TYPE_P (type))
820 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
821 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
822 if (processing_template_decl)
824 if (push_template_decl (TYPE_MAIN_DECL (type))
826 return error_mark_node;
829 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
830 error ("specialization of %qT after instantiation", type);
832 else if (CLASS_TYPE_P (type)
833 && !CLASSTYPE_USE_TEMPLATE (type)
834 && CLASSTYPE_TEMPLATE_INFO (type)
835 && context && CLASS_TYPE_P (context)
836 && CLASSTYPE_TEMPLATE_INFO (context))
838 /* This is for an explicit specialization of member class
839 template according to [temp.expl.spec/18]:
841 template <> template <class U> class C<int>::D;
843 The context `C<int>' must be an implicit instantiation.
844 Otherwise this is just a member class template declared
847 template <> class C<int> { template <class U> class D; };
848 template <> template <class U> class C<int>::D;
850 In the first case, `C<int>::D' is a specialization of `C<T>::D'
851 while in the second case, `C<int>::D' is a primary template
852 and `C<T>::D' may not exist. */
854 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
855 && !COMPLETE_TYPE_P (type))
858 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
860 if (current_namespace
861 != decl_namespace_context (tmpl))
863 permerror (input_location, "specializing %q#T in different namespace", type);
864 permerror (input_location, " from definition of %q+#D", tmpl);
867 /* Check for invalid specialization after instantiation:
869 template <> template <> class C<int>::D<int>;
870 template <> template <class U> class C<int>::D; */
872 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
873 t; t = TREE_CHAIN (t))
875 tree inst = TREE_VALUE (t);
876 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
878 /* We already have a full specialization of this partial
879 instantiation. Reassign it to the new member
880 specialization template. */
884 elt.tmpl = most_general_template (tmpl);
885 elt.args = CLASSTYPE_TI_ARGS (inst);
888 htab_remove_elt (type_specializations, &elt);
891 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
893 slot = (spec_entry **)
894 htab_find_slot (type_specializations, &elt, INSERT);
895 *slot = ggc_alloc_spec_entry ();
898 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
899 /* But if we've had an implicit instantiation, that's a
900 problem ([temp.expl.spec]/6). */
901 error ("specialization %qT after instantiation %qT",
905 /* Mark TYPE as a specialization. And as a result, we only
906 have one level of template argument for the innermost
908 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
909 CLASSTYPE_TI_ARGS (type)
910 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
913 else if (processing_specialization)
915 /* Someday C++0x may allow for enum template specialization. */
916 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
917 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
918 pedwarn (input_location, OPT_pedantic, "template specialization "
919 "of %qD not allowed by ISO C++", type);
922 error ("explicit specialization of non-template %qT", type);
923 return error_mark_node;
930 /* Returns nonzero if we can optimize the retrieval of specializations
931 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
932 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
935 optimize_specialization_lookup_p (tree tmpl)
937 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
938 && DECL_CLASS_SCOPE_P (tmpl)
939 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
941 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
942 /* The optimized lookup depends on the fact that the
943 template arguments for the member function template apply
944 purely to the containing class, which is not true if the
945 containing class is an explicit or partial
947 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
948 && !DECL_MEMBER_TEMPLATE_P (tmpl)
949 && !DECL_CONV_FN_P (tmpl)
950 /* It is possible to have a template that is not a member
951 template and is not a member of a template class:
953 template <typename T>
954 struct S { friend A::f(); };
956 Here, the friend function is a template, but the context does
957 not have template information. The optimized lookup relies
958 on having ARGS be the template arguments for both the class
959 and the function template. */
960 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
963 /* Retrieve the specialization (in the sense of [temp.spec] - a
964 specialization is either an instantiation or an explicit
965 specialization) of TMPL for the given template ARGS. If there is
966 no such specialization, return NULL_TREE. The ARGS are a vector of
967 arguments, or a vector of vectors of arguments, in the case of
968 templates with more than one level of parameters.
970 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
971 then we search for a partial specialization matching ARGS. This
972 parameter is ignored if TMPL is not a class template. */
975 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
977 if (args == error_mark_node)
980 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
982 /* There should be as many levels of arguments as there are
983 levels of parameters. */
984 gcc_assert (TMPL_ARGS_DEPTH (args)
985 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
987 if (optimize_specialization_lookup_p (tmpl))
990 tree class_specialization;
991 VEC(tree,gc) *methods;
995 /* The template arguments actually apply to the containing
996 class. Find the class specialization with those
998 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1000 = retrieve_specialization (class_template, args, 0);
1001 if (!class_specialization)
1003 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1004 for the specialization. */
1005 idx = class_method_index_for_fn (class_specialization, tmpl);
1008 /* Iterate through the methods with the indicated name, looking
1009 for the one that has an instance of TMPL. */
1010 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1011 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1013 tree fn = OVL_CURRENT (fns);
1014 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1015 /* using-declarations can add base methods to the method vec,
1016 and we don't want those here. */
1017 && DECL_CONTEXT (fn) == class_specialization)
1026 htab_t specializations;
1030 elt.spec = NULL_TREE;
1032 if (DECL_CLASS_TEMPLATE_P (tmpl))
1033 specializations = type_specializations;
1035 specializations = decl_specializations;
1038 hash = hash_specialization (&elt);
1039 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1047 /* Like retrieve_specialization, but for local declarations. */
1050 retrieve_local_specialization (tree tmpl)
1054 if (local_specializations == NULL)
1057 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1058 htab_hash_pointer (tmpl));
1059 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1062 /* Returns nonzero iff DECL is a specialization of TMPL. */
1065 is_specialization_of (tree decl, tree tmpl)
1069 if (TREE_CODE (decl) == FUNCTION_DECL)
1073 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1079 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1081 for (t = TREE_TYPE (decl);
1083 t = CLASSTYPE_USE_TEMPLATE (t)
1084 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1085 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1092 /* Returns nonzero iff DECL is a specialization of friend declaration
1093 FRIEND_DECL according to [temp.friend]. */
1096 is_specialization_of_friend (tree decl, tree friend_decl)
1098 bool need_template = true;
1101 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1102 || TREE_CODE (decl) == TYPE_DECL);
1104 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1105 of a template class, we want to check if DECL is a specialization
1107 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1108 && DECL_TEMPLATE_INFO (friend_decl)
1109 && !DECL_USE_TEMPLATE (friend_decl))
1111 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1112 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1113 need_template = false;
1115 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1116 && !PRIMARY_TEMPLATE_P (friend_decl))
1117 need_template = false;
1119 /* There is nothing to do if this is not a template friend. */
1120 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1123 if (is_specialization_of (decl, friend_decl))
1127 A member of a class template may be declared to be a friend of a
1128 non-template class. In this case, the corresponding member of
1129 every specialization of the class template is a friend of the
1130 class granting friendship.
1132 For example, given a template friend declaration
1134 template <class T> friend void A<T>::f();
1136 the member function below is considered a friend
1138 template <> struct A<int> {
1142 For this type of template friend, TEMPLATE_DEPTH below will be
1143 nonzero. To determine if DECL is a friend of FRIEND, we first
1144 check if the enclosing class is a specialization of another. */
1146 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1148 && DECL_CLASS_SCOPE_P (decl)
1149 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1150 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1152 /* Next, we check the members themselves. In order to handle
1153 a few tricky cases, such as when FRIEND_DECL's are
1155 template <class T> friend void A<T>::g(T t);
1156 template <class T> template <T t> friend void A<T>::h();
1160 void A<int>::g(int);
1161 template <int> void A<int>::h();
1163 we need to figure out ARGS, the template arguments from
1164 the context of DECL. This is required for template substitution
1165 of `T' in the function parameter of `g' and template parameter
1166 of `h' in the above examples. Here ARGS corresponds to `int'. */
1168 tree context = DECL_CONTEXT (decl);
1169 tree args = NULL_TREE;
1170 int current_depth = 0;
1172 while (current_depth < template_depth)
1174 if (CLASSTYPE_TEMPLATE_INFO (context))
1176 if (current_depth == 0)
1177 args = TYPE_TI_ARGS (context);
1179 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1182 context = TYPE_CONTEXT (context);
1185 if (TREE_CODE (decl) == FUNCTION_DECL)
1190 tree friend_args_type;
1191 tree decl_args_type;
1193 /* Make sure that both DECL and FRIEND_DECL are templates or
1195 is_template = DECL_TEMPLATE_INFO (decl)
1196 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1197 if (need_template ^ is_template)
1199 else if (is_template)
1201 /* If both are templates, check template parameter list. */
1203 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1205 if (!comp_template_parms
1206 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1210 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1213 decl_type = TREE_TYPE (decl);
1215 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1216 tf_none, NULL_TREE);
1217 if (friend_type == error_mark_node)
1220 /* Check if return types match. */
1221 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1224 /* Check if function parameter types match, ignoring the
1225 `this' parameter. */
1226 friend_args_type = TYPE_ARG_TYPES (friend_type);
1227 decl_args_type = TYPE_ARG_TYPES (decl_type);
1228 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1229 friend_args_type = TREE_CHAIN (friend_args_type);
1230 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1231 decl_args_type = TREE_CHAIN (decl_args_type);
1233 return compparms (decl_args_type, friend_args_type);
1237 /* DECL is a TYPE_DECL */
1239 tree decl_type = TREE_TYPE (decl);
1241 /* Make sure that both DECL and FRIEND_DECL are templates or
1244 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1245 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1247 if (need_template ^ is_template)
1249 else if (is_template)
1252 /* If both are templates, check the name of the two
1253 TEMPLATE_DECL's first because is_friend didn't. */
1254 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1255 != DECL_NAME (friend_decl))
1258 /* Now check template parameter list. */
1260 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1262 return comp_template_parms
1263 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1267 return (DECL_NAME (decl)
1268 == DECL_NAME (friend_decl));
1274 /* Register the specialization SPEC as a specialization of TMPL with
1275 the indicated ARGS. IS_FRIEND indicates whether the specialization
1276 is actually just a friend declaration. Returns SPEC, or an
1277 equivalent prior declaration, if available. */
1280 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1284 spec_entry **slot = NULL;
1287 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1289 if (TREE_CODE (spec) == FUNCTION_DECL
1290 && uses_template_parms (DECL_TI_ARGS (spec)))
1291 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1292 register it; we want the corresponding TEMPLATE_DECL instead.
1293 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1294 the more obvious `uses_template_parms (spec)' to avoid problems
1295 with default function arguments. In particular, given
1296 something like this:
1298 template <class T> void f(T t1, T t = T())
1300 the default argument expression is not substituted for in an
1301 instantiation unless and until it is actually needed. */
1304 if (optimize_specialization_lookup_p (tmpl))
1305 /* We don't put these specializations in the hash table, but we might
1306 want to give an error about a mismatch. */
1307 fn = retrieve_specialization (tmpl, args, 0);
1315 hash = hash_specialization (&elt);
1317 slot = (spec_entry **)
1318 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1325 /* We can sometimes try to re-register a specialization that we've
1326 already got. In particular, regenerate_decl_from_template calls
1327 duplicate_decls which will update the specialization list. But,
1328 we'll still get called again here anyhow. It's more convenient
1329 to simply allow this than to try to prevent it. */
1332 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1334 if (DECL_TEMPLATE_INSTANTIATION (fn))
1336 if (DECL_ODR_USED (fn)
1337 || DECL_EXPLICIT_INSTANTIATION (fn))
1339 error ("specialization of %qD after instantiation",
1341 return error_mark_node;
1346 /* This situation should occur only if the first
1347 specialization is an implicit instantiation, the
1348 second is an explicit specialization, and the
1349 implicit instantiation has not yet been used. That
1350 situation can occur if we have implicitly
1351 instantiated a member function and then specialized
1354 We can also wind up here if a friend declaration that
1355 looked like an instantiation turns out to be a
1358 template <class T> void foo(T);
1359 class S { friend void foo<>(int) };
1360 template <> void foo(int);
1362 We transform the existing DECL in place so that any
1363 pointers to it become pointers to the updated
1366 If there was a definition for the template, but not
1367 for the specialization, we want this to look as if
1368 there were no definition, and vice versa. */
1369 DECL_INITIAL (fn) = NULL_TREE;
1370 duplicate_decls (spec, fn, is_friend);
1371 /* The call to duplicate_decls will have applied
1374 An explicit specialization of a function template
1375 is inline only if it is explicitly declared to be,
1376 and independently of whether its function template
1379 to the primary function; now copy the inline bits to
1380 the various clones. */
1381 FOR_EACH_CLONE (clone, fn)
1383 DECL_DECLARED_INLINE_P (clone)
1384 = DECL_DECLARED_INLINE_P (fn);
1385 DECL_SOURCE_LOCATION (clone)
1386 = DECL_SOURCE_LOCATION (fn);
1388 check_specialization_namespace (fn);
1393 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1395 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1396 /* Dup decl failed, but this is a new definition. Set the
1397 line number so any errors match this new
1399 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1405 return duplicate_decls (spec, fn, is_friend);
1407 /* A specialization must be declared in the same namespace as the
1408 template it is specializing. */
1409 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1410 && !check_specialization_namespace (tmpl))
1411 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1413 if (!optimize_specialization_lookup_p (tmpl))
1415 gcc_assert (tmpl && args && spec);
1416 *slot = ggc_alloc_spec_entry ();
1418 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1419 && PRIMARY_TEMPLATE_P (tmpl)
1420 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1421 /* TMPL is a forward declaration of a template function; keep a list
1422 of all specializations in case we need to reassign them to a friend
1423 template later in tsubst_friend_function. */
1424 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1425 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1431 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1432 TMPL and ARGS members, ignores SPEC. */
1435 eq_specializations (const void *p1, const void *p2)
1437 const spec_entry *e1 = (const spec_entry *)p1;
1438 const spec_entry *e2 = (const spec_entry *)p2;
1440 return (e1->tmpl == e2->tmpl
1441 && comp_template_args (e1->args, e2->args));
1444 /* Returns a hash for a template TMPL and template arguments ARGS. */
1447 hash_tmpl_and_args (tree tmpl, tree args)
1449 hashval_t val = DECL_UID (tmpl);
1450 return iterative_hash_template_arg (args, val);
1453 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1457 hash_specialization (const void *p)
1459 const spec_entry *e = (const spec_entry *)p;
1460 return hash_tmpl_and_args (e->tmpl, e->args);
1463 /* Recursively calculate a hash value for a template argument ARG, for use
1464 in the hash tables of template specializations. */
1467 iterative_hash_template_arg (tree arg, hashval_t val)
1469 unsigned HOST_WIDE_INT i;
1470 enum tree_code code;
1473 if (arg == NULL_TREE)
1474 return iterative_hash_object (arg, val);
1479 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1480 /* We can get one of these when re-hashing a previous entry in the middle
1481 of substituting into a pack expansion. Just look through it. */
1482 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1484 code = TREE_CODE (arg);
1485 tclass = TREE_CODE_CLASS (code);
1487 val = iterative_hash_object (code, val);
1494 case IDENTIFIER_NODE:
1495 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1499 int i, len = TREE_VEC_LENGTH (arg);
1500 for (i = 0; i < len; ++i)
1501 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1505 case TYPE_PACK_EXPANSION:
1506 case EXPR_PACK_EXPANSION:
1507 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1509 case TYPE_ARGUMENT_PACK:
1510 case NONTYPE_ARGUMENT_PACK:
1511 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1514 for (; arg; arg = TREE_CHAIN (arg))
1515 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1519 for (; arg; arg = OVL_NEXT (arg))
1520 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1526 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1528 val = iterative_hash_template_arg (field, val);
1529 val = iterative_hash_template_arg (value, val);
1535 if (!DECL_ARTIFICIAL (arg))
1537 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1538 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1540 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1543 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1546 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1547 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1549 case TEMPLATE_PARM_INDEX:
1550 val = iterative_hash_template_arg
1551 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1552 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1553 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1556 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1557 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1558 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1561 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1563 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1567 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1568 code = TREE_CODE (TREE_OPERAND (arg, 1));
1569 val = iterative_hash_object (code, val);
1570 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1573 /* A lambda can't appear in a template arg, but don't crash on
1575 gcc_assert (seen_error ());
1579 case STATIC_CAST_EXPR:
1580 case REINTERPRET_CAST_EXPR:
1581 case CONST_CAST_EXPR:
1582 case DYNAMIC_CAST_EXPR:
1584 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1585 /* Now hash operands as usual. */
1595 if (TYPE_CANONICAL (arg))
1596 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1598 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1599 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1600 /* Otherwise just compare the types during lookup. */
1603 case tcc_declaration:
1605 return iterative_hash_expr (arg, val);
1608 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1610 unsigned n = TREE_OPERAND_LENGTH (arg);
1611 for (i = 0; i < n; ++i)
1612 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1620 /* Unregister the specialization SPEC as a specialization of TMPL.
1621 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1622 if the SPEC was listed as a specialization of TMPL.
1624 Note that SPEC has been ggc_freed, so we can't look inside it. */
1627 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1632 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1633 elt.args = TI_ARGS (tinfo);
1634 elt.spec = NULL_TREE;
1636 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1639 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1640 gcc_assert (new_spec != NULL_TREE);
1641 (*slot)->spec = new_spec;
1648 /* Compare an entry in the local specializations hash table P1 (which
1649 is really a pointer to a TREE_LIST) with P2 (which is really a
1653 eq_local_specializations (const void *p1, const void *p2)
1655 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1658 /* Hash P1, an entry in the local specializations table. */
1661 hash_local_specialization (const void* p1)
1663 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1666 /* Like register_specialization, but for local declarations. We are
1667 registering SPEC, an instantiation of TMPL. */
1670 register_local_specialization (tree spec, tree tmpl)
1674 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1675 htab_hash_pointer (tmpl), INSERT);
1676 *slot = build_tree_list (spec, tmpl);
1679 /* TYPE is a class type. Returns true if TYPE is an explicitly
1680 specialized class. */
1683 explicit_class_specialization_p (tree type)
1685 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1687 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1690 /* Print the list of functions at FNS, going through all the overloads
1691 for each element of the list. Alternatively, FNS can not be a
1692 TREE_LIST, in which case it will be printed together with all the
1695 MORE and *STR should respectively be FALSE and NULL when the function
1696 is called from the outside. They are used internally on recursive
1697 calls. print_candidates manages the two parameters and leaves NULL
1698 in *STR when it ends. */
1701 print_candidates_1 (tree fns, bool more, const char **str)
1704 char *spaces = NULL;
1706 for (fn = fns; fn; fn = OVL_NEXT (fn))
1707 if (TREE_CODE (fn) == TREE_LIST)
1709 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1710 print_candidates_1 (TREE_VALUE (fn2),
1711 TREE_CHAIN (fn2) || more, str);
1717 /* Pick the prefix string. */
1718 if (!more && !OVL_NEXT (fns))
1720 error ("candidate is: %+#D", OVL_CURRENT (fn));
1724 *str = _("candidates are:");
1725 spaces = get_spaces (*str);
1727 error ("%s %+#D", *str, OVL_CURRENT (fn));
1728 *str = spaces ? spaces : *str;
1738 /* Print the list of candidate FNS in an error message. FNS can also
1739 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1742 print_candidates (tree fns)
1744 const char *str = NULL;
1745 print_candidates_1 (fns, false, &str);
1746 gcc_assert (str == NULL);
1749 /* Returns the template (one of the functions given by TEMPLATE_ID)
1750 which can be specialized to match the indicated DECL with the
1751 explicit template args given in TEMPLATE_ID. The DECL may be
1752 NULL_TREE if none is available. In that case, the functions in
1753 TEMPLATE_ID are non-members.
1755 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1756 specialization of a member template.
1758 The TEMPLATE_COUNT is the number of references to qualifying
1759 template classes that appeared in the name of the function. See
1760 check_explicit_specialization for a more accurate description.
1762 TSK indicates what kind of template declaration (if any) is being
1763 declared. TSK_TEMPLATE indicates that the declaration given by
1764 DECL, though a FUNCTION_DECL, has template parameters, and is
1765 therefore a template function.
1767 The template args (those explicitly specified and those deduced)
1768 are output in a newly created vector *TARGS_OUT.
1770 If it is impossible to determine the result, an error message is
1771 issued. The error_mark_node is returned to indicate failure. */
1774 determine_specialization (tree template_id,
1777 int need_member_template,
1783 tree explicit_targs;
1784 tree candidates = NULL_TREE;
1785 /* A TREE_LIST of templates of which DECL may be a specialization.
1786 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1787 corresponding TREE_PURPOSE is the set of template arguments that,
1788 when used to instantiate the template, would produce a function
1789 with the signature of DECL. */
1790 tree templates = NULL_TREE;
1792 struct cp_binding_level *b;
1794 *targs_out = NULL_TREE;
1796 if (template_id == error_mark_node || decl == error_mark_node)
1797 return error_mark_node;
1799 fns = TREE_OPERAND (template_id, 0);
1800 explicit_targs = TREE_OPERAND (template_id, 1);
1802 if (fns == error_mark_node)
1803 return error_mark_node;
1805 /* Check for baselinks. */
1806 if (BASELINK_P (fns))
1807 fns = BASELINK_FUNCTIONS (fns);
1809 if (!is_overloaded_fn (fns))
1811 error ("%qD is not a function template", fns);
1812 return error_mark_node;
1815 /* Count the number of template headers specified for this
1818 for (b = current_binding_level;
1819 b->kind == sk_template_parms;
1823 for (; fns; fns = OVL_NEXT (fns))
1825 tree fn = OVL_CURRENT (fns);
1827 if (TREE_CODE (fn) == TEMPLATE_DECL)
1829 tree decl_arg_types;
1832 /* In case of explicit specialization, we need to check if
1833 the number of template headers appearing in the specialization
1834 is correct. This is usually done in check_explicit_specialization,
1835 but the check done there cannot be exhaustive when specializing
1836 member functions. Consider the following code:
1838 template <> void A<int>::f(int);
1839 template <> template <> void A<int>::f(int);
1841 Assuming that A<int> is not itself an explicit specialization
1842 already, the first line specializes "f" which is a non-template
1843 member function, whilst the second line specializes "f" which
1844 is a template member function. So both lines are syntactically
1845 correct, and check_explicit_specialization does not reject
1848 Here, we can do better, as we are matching the specialization
1849 against the declarations. We count the number of template
1850 headers, and we check if they match TEMPLATE_COUNT + 1
1851 (TEMPLATE_COUNT is the number of qualifying template classes,
1852 plus there must be another header for the member template
1855 Notice that if header_count is zero, this is not a
1856 specialization but rather a template instantiation, so there
1857 is no check we can perform here. */
1858 if (header_count && header_count != template_count + 1)
1861 /* Check that the number of template arguments at the
1862 innermost level for DECL is the same as for FN. */
1863 if (current_binding_level->kind == sk_template_parms
1864 && !current_binding_level->explicit_spec_p
1865 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1866 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1867 (current_template_parms))))
1870 /* DECL might be a specialization of FN. */
1871 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1872 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1874 /* For a non-static member function, we need to make sure
1875 that the const qualification is the same. Since
1876 get_bindings does not try to merge the "this" parameter,
1877 we must do the comparison explicitly. */
1878 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1879 && !same_type_p (TREE_VALUE (fn_arg_types),
1880 TREE_VALUE (decl_arg_types)))
1883 /* Skip the "this" parameter and, for constructors of
1884 classes with virtual bases, the VTT parameter. A
1885 full specialization of a constructor will have a VTT
1886 parameter, but a template never will. */
1888 = skip_artificial_parms_for (decl, decl_arg_types);
1890 = skip_artificial_parms_for (fn, fn_arg_types);
1892 /* Check that the number of function parameters matches.
1894 template <class T> void f(int i = 0);
1895 template <> void f<int>();
1896 The specialization f<int> is invalid but is not caught
1897 by get_bindings below. */
1898 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1901 /* Function templates cannot be specializations; there are
1902 no partial specializations of functions. Therefore, if
1903 the type of DECL does not match FN, there is no
1905 if (tsk == tsk_template)
1907 if (compparms (fn_arg_types, decl_arg_types))
1908 candidates = tree_cons (NULL_TREE, fn, candidates);
1912 /* See whether this function might be a specialization of this
1914 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1917 /* We cannot deduce template arguments that when used to
1918 specialize TMPL will produce DECL. */
1921 /* Save this template, and the arguments deduced. */
1922 templates = tree_cons (targs, fn, templates);
1924 else if (need_member_template)
1925 /* FN is an ordinary member function, and we need a
1926 specialization of a member template. */
1928 else if (TREE_CODE (fn) != FUNCTION_DECL)
1929 /* We can get IDENTIFIER_NODEs here in certain erroneous
1932 else if (!DECL_FUNCTION_MEMBER_P (fn))
1933 /* This is just an ordinary non-member function. Nothing can
1934 be a specialization of that. */
1936 else if (DECL_ARTIFICIAL (fn))
1937 /* Cannot specialize functions that are created implicitly. */
1941 tree decl_arg_types;
1943 /* This is an ordinary member function. However, since
1944 we're here, we can assume it's enclosing class is a
1945 template class. For example,
1947 template <typename T> struct S { void f(); };
1948 template <> void S<int>::f() {}
1950 Here, S<int>::f is a non-template, but S<int> is a
1951 template class. If FN has the same type as DECL, we
1952 might be in business. */
1954 if (!DECL_TEMPLATE_INFO (fn))
1955 /* Its enclosing class is an explicit specialization
1956 of a template class. This is not a candidate. */
1959 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1960 TREE_TYPE (TREE_TYPE (fn))))
1961 /* The return types differ. */
1964 /* Adjust the type of DECL in case FN is a static member. */
1965 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1966 if (DECL_STATIC_FUNCTION_P (fn)
1967 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1968 decl_arg_types = TREE_CHAIN (decl_arg_types);
1970 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1973 candidates = tree_cons (NULL_TREE, fn, candidates);
1977 if (templates && TREE_CHAIN (templates))
1983 It is possible for a specialization with a given function
1984 signature to be instantiated from more than one function
1985 template. In such cases, explicit specification of the
1986 template arguments must be used to uniquely identify the
1987 function template specialization being specialized.
1989 Note that here, there's no suggestion that we're supposed to
1990 determine which of the candidate templates is most
1991 specialized. However, we, also have:
1995 Partial ordering of overloaded function template
1996 declarations is used in the following contexts to select
1997 the function template to which a function template
1998 specialization refers:
2000 -- when an explicit specialization refers to a function
2003 So, we do use the partial ordering rules, at least for now.
2004 This extension can only serve to make invalid programs valid,
2005 so it's safe. And, there is strong anecdotal evidence that
2006 the committee intended the partial ordering rules to apply;
2007 the EDG front end has that behavior, and John Spicer claims
2008 that the committee simply forgot to delete the wording in
2009 [temp.expl.spec]. */
2010 tree tmpl = most_specialized_instantiation (templates);
2011 if (tmpl != error_mark_node)
2014 TREE_CHAIN (templates) = NULL_TREE;
2018 if (templates == NULL_TREE && candidates == NULL_TREE)
2020 error ("template-id %qD for %q+D does not match any template "
2021 "declaration", template_id, decl);
2022 if (header_count && header_count != template_count + 1)
2023 inform (input_location, "saw %d %<template<>%>, need %d for "
2024 "specializing a member function template",
2025 header_count, template_count + 1);
2026 return error_mark_node;
2028 else if ((templates && TREE_CHAIN (templates))
2029 || (candidates && TREE_CHAIN (candidates))
2030 || (templates && candidates))
2032 error ("ambiguous template specialization %qD for %q+D",
2034 candidates = chainon (candidates, templates);
2035 print_candidates (candidates);
2036 return error_mark_node;
2039 /* We have one, and exactly one, match. */
2042 tree fn = TREE_VALUE (candidates);
2043 *targs_out = copy_node (DECL_TI_ARGS (fn));
2044 /* DECL is a re-declaration or partial instantiation of a template
2046 if (TREE_CODE (fn) == TEMPLATE_DECL)
2048 /* It was a specialization of an ordinary member function in a
2050 return DECL_TI_TEMPLATE (fn);
2053 /* It was a specialization of a template. */
2054 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2055 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2057 *targs_out = copy_node (targs);
2058 SET_TMPL_ARGS_LEVEL (*targs_out,
2059 TMPL_ARGS_DEPTH (*targs_out),
2060 TREE_PURPOSE (templates));
2063 *targs_out = TREE_PURPOSE (templates);
2064 return TREE_VALUE (templates);
2067 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2068 but with the default argument values filled in from those in the
2072 copy_default_args_to_explicit_spec_1 (tree spec_types,
2075 tree new_spec_types;
2080 if (spec_types == void_list_node)
2081 return void_list_node;
2083 /* Substitute into the rest of the list. */
2085 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2086 TREE_CHAIN (tmpl_types));
2088 /* Add the default argument for this parameter. */
2089 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2090 TREE_VALUE (spec_types),
2094 /* DECL is an explicit specialization. Replicate default arguments
2095 from the template it specializes. (That way, code like:
2097 template <class T> void f(T = 3);
2098 template <> void f(double);
2101 works, as required.) An alternative approach would be to look up
2102 the correct default arguments at the call-site, but this approach
2103 is consistent with how implicit instantiations are handled. */
2106 copy_default_args_to_explicit_spec (tree decl)
2111 tree new_spec_types;
2115 tree object_type = NULL_TREE;
2116 tree in_charge = NULL_TREE;
2117 tree vtt = NULL_TREE;
2119 /* See if there's anything we need to do. */
2120 tmpl = DECL_TI_TEMPLATE (decl);
2121 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2122 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2123 if (TREE_PURPOSE (t))
2128 old_type = TREE_TYPE (decl);
2129 spec_types = TYPE_ARG_TYPES (old_type);
2131 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2133 /* Remove the this pointer, but remember the object's type for
2135 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2136 spec_types = TREE_CHAIN (spec_types);
2137 tmpl_types = TREE_CHAIN (tmpl_types);
2139 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2141 /* DECL may contain more parameters than TMPL due to the extra
2142 in-charge parameter in constructors and destructors. */
2143 in_charge = spec_types;
2144 spec_types = TREE_CHAIN (spec_types);
2146 if (DECL_HAS_VTT_PARM_P (decl))
2149 spec_types = TREE_CHAIN (spec_types);
2153 /* Compute the merged default arguments. */
2155 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2157 /* Compute the new FUNCTION_TYPE. */
2161 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2166 /* Put the in-charge parameter back. */
2167 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2168 TREE_VALUE (in_charge),
2171 new_type = build_method_type_directly (object_type,
2172 TREE_TYPE (old_type),
2176 new_type = build_function_type (TREE_TYPE (old_type),
2178 new_type = cp_build_type_attribute_variant (new_type,
2179 TYPE_ATTRIBUTES (old_type));
2180 new_type = build_exception_variant (new_type,
2181 TYPE_RAISES_EXCEPTIONS (old_type));
2182 TREE_TYPE (decl) = new_type;
2185 /* Check to see if the function just declared, as indicated in
2186 DECLARATOR, and in DECL, is a specialization of a function
2187 template. We may also discover that the declaration is an explicit
2188 instantiation at this point.
2190 Returns DECL, or an equivalent declaration that should be used
2191 instead if all goes well. Issues an error message if something is
2192 amiss. Returns error_mark_node if the error is not easily
2195 FLAGS is a bitmask consisting of the following flags:
2197 2: The function has a definition.
2198 4: The function is a friend.
2200 The TEMPLATE_COUNT is the number of references to qualifying
2201 template classes that appeared in the name of the function. For
2204 template <class T> struct S { void f(); };
2207 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2208 classes are not counted in the TEMPLATE_COUNT, so that in
2210 template <class T> struct S {};
2211 template <> struct S<int> { void f(); }
2212 template <> void S<int>::f();
2214 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2215 invalid; there should be no template <>.)
2217 If the function is a specialization, it is marked as such via
2218 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2219 is set up correctly, and it is added to the list of specializations
2220 for that template. */
2223 check_explicit_specialization (tree declarator,
2228 int have_def = flags & 2;
2229 int is_friend = flags & 4;
2230 int specialization = 0;
2231 int explicit_instantiation = 0;
2232 int member_specialization = 0;
2233 tree ctype = DECL_CLASS_CONTEXT (decl);
2234 tree dname = DECL_NAME (decl);
2239 if (!processing_specialization)
2242 tsk = tsk_excessive_parms;
2245 tsk = current_tmpl_spec_kind (template_count);
2250 if (processing_specialization)
2253 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2255 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2258 /* This could be something like:
2260 template <class T> void f(T);
2261 class S { friend void f<>(int); } */
2265 /* This case handles bogus declarations like template <>
2266 template <class T> void f<int>(); */
2268 error ("template-id %qD in declaration of primary template",
2275 case tsk_invalid_member_spec:
2276 /* The error has already been reported in
2277 check_specialization_scope. */
2278 return error_mark_node;
2280 case tsk_invalid_expl_inst:
2281 error ("template parameter list used in explicit instantiation");
2287 error ("definition provided for explicit instantiation");
2289 explicit_instantiation = 1;
2292 case tsk_excessive_parms:
2293 case tsk_insufficient_parms:
2294 if (tsk == tsk_excessive_parms)
2295 error ("too many template parameter lists in declaration of %qD",
2297 else if (template_header_count)
2298 error("too few template parameter lists in declaration of %qD", decl);
2300 error("explicit specialization of %qD must be introduced by "
2301 "%<template <>%>", decl);
2305 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2307 member_specialization = 1;
2313 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2315 /* This case handles bogus declarations like template <>
2316 template <class T> void f<int>(); */
2318 if (uses_template_parms (declarator))
2319 error ("function template partial specialization %qD "
2320 "is not allowed", declarator);
2322 error ("template-id %qD in declaration of primary template",
2327 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2328 /* This is a specialization of a member template, without
2329 specialization the containing class. Something like:
2331 template <class T> struct S {
2332 template <class U> void f (U);
2334 template <> template <class U> void S<int>::f(U) {}
2336 That's a specialization -- but of the entire template. */
2344 if (specialization || member_specialization)
2346 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2347 for (; t; t = TREE_CHAIN (t))
2348 if (TREE_PURPOSE (t))
2350 permerror (input_location,
2351 "default argument specified in explicit specialization");
2356 if (specialization || member_specialization || explicit_instantiation)
2358 tree tmpl = NULL_TREE;
2359 tree targs = NULL_TREE;
2361 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2362 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2366 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2371 /* If there is no class context, the explicit instantiation
2372 must be at namespace scope. */
2373 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2375 /* Find the namespace binding, using the declaration
2377 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2379 if (fns == error_mark_node || !is_overloaded_fn (fns))
2381 error ("%qD is not a template function", dname);
2382 fns = error_mark_node;
2386 tree fn = OVL_CURRENT (fns);
2387 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2388 CP_DECL_CONTEXT (fn)))
2389 error ("%qD is not declared in %qD",
2390 decl, current_namespace);
2394 declarator = lookup_template_function (fns, NULL_TREE);
2397 if (declarator == error_mark_node)
2398 return error_mark_node;
2400 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2402 if (!explicit_instantiation)
2403 /* A specialization in class scope. This is invalid,
2404 but the error will already have been flagged by
2405 check_specialization_scope. */
2406 return error_mark_node;
2409 /* It's not valid to write an explicit instantiation in
2412 class C { template void f(); }
2414 This case is caught by the parser. However, on
2417 template class C { void f(); };
2419 (which is invalid) we can get here. The error will be
2426 else if (ctype != NULL_TREE
2427 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2430 /* Find the list of functions in ctype that have the same
2431 name as the declared function. */
2432 tree name = TREE_OPERAND (declarator, 0);
2433 tree fns = NULL_TREE;
2436 if (constructor_name_p (name, ctype))
2438 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2440 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2441 : !CLASSTYPE_DESTRUCTORS (ctype))
2443 /* From [temp.expl.spec]:
2445 If such an explicit specialization for the member
2446 of a class template names an implicitly-declared
2447 special member function (clause _special_), the
2448 program is ill-formed.
2450 Similar language is found in [temp.explicit]. */
2451 error ("specialization of implicitly-declared special member function");
2452 return error_mark_node;
2455 name = is_constructor ? ctor_identifier : dtor_identifier;
2458 if (!DECL_CONV_FN_P (decl))
2460 idx = lookup_fnfields_1 (ctype, name);
2462 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2466 VEC(tree,gc) *methods;
2469 /* For a type-conversion operator, we cannot do a
2470 name-based lookup. We might be looking for `operator
2471 int' which will be a specialization of `operator T'.
2472 So, we find *all* the conversion operators, and then
2473 select from them. */
2476 methods = CLASSTYPE_METHOD_VEC (ctype);
2478 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2479 VEC_iterate (tree, methods, idx, ovl);
2482 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2483 /* There are no more conversion functions. */
2486 /* Glue all these conversion functions together
2487 with those we already have. */
2488 for (; ovl; ovl = OVL_NEXT (ovl))
2489 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2493 if (fns == NULL_TREE)
2495 error ("no member function %qD declared in %qT", name, ctype);
2496 return error_mark_node;
2499 TREE_OPERAND (declarator, 0) = fns;
2502 /* Figure out what exactly is being specialized at this point.
2503 Note that for an explicit instantiation, even one for a
2504 member function, we cannot tell apriori whether the
2505 instantiation is for a member template, or just a member
2506 function of a template class. Even if a member template is
2507 being instantiated, the member template arguments may be
2508 elided if they can be deduced from the rest of the
2510 tmpl = determine_specialization (declarator, decl,
2512 member_specialization,
2516 if (!tmpl || tmpl == error_mark_node)
2517 /* We couldn't figure out what this declaration was
2519 return error_mark_node;
2522 tree gen_tmpl = most_general_template (tmpl);
2524 if (explicit_instantiation)
2526 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2527 is done by do_decl_instantiation later. */
2529 int arg_depth = TMPL_ARGS_DEPTH (targs);
2530 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2532 if (arg_depth > parm_depth)
2534 /* If TMPL is not the most general template (for
2535 example, if TMPL is a friend template that is
2536 injected into namespace scope), then there will
2537 be too many levels of TARGS. Remove some of them
2542 new_targs = make_tree_vec (parm_depth);
2543 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2544 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2545 = TREE_VEC_ELT (targs, i);
2549 return instantiate_template (tmpl, targs, tf_error);
2552 /* If we thought that the DECL was a member function, but it
2553 turns out to be specializing a static member function,
2554 make DECL a static member function as well. */
2555 if (DECL_STATIC_FUNCTION_P (tmpl)
2556 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2557 revert_static_member_fn (decl);
2559 /* If this is a specialization of a member template of a
2560 template class, we want to return the TEMPLATE_DECL, not
2561 the specialization of it. */
2562 if (tsk == tsk_template)
2564 tree result = DECL_TEMPLATE_RESULT (tmpl);
2565 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2566 DECL_INITIAL (result) = NULL_TREE;
2570 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2571 DECL_SOURCE_LOCATION (result)
2572 = DECL_SOURCE_LOCATION (decl);
2573 /* We want to use the argument list specified in the
2574 definition, not in the original declaration. */
2575 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2576 for (parm = DECL_ARGUMENTS (result); parm;
2577 parm = DECL_CHAIN (parm))
2578 DECL_CONTEXT (parm) = result;
2580 return register_specialization (tmpl, gen_tmpl, targs,
2584 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2585 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2587 /* Inherit default function arguments from the template
2588 DECL is specializing. */
2589 copy_default_args_to_explicit_spec (decl);
2591 /* This specialization has the same protection as the
2592 template it specializes. */
2593 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2594 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2596 /* 7.1.1-1 [dcl.stc]
2598 A storage-class-specifier shall not be specified in an
2599 explicit specialization...
2601 The parser rejects these, so unless action is taken here,
2602 explicit function specializations will always appear with
2605 The action recommended by the C++ CWG in response to C++
2606 defect report 605 is to make the storage class and linkage
2607 of the explicit specialization match the templated function:
2609 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2611 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2613 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2614 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2616 /* This specialization has the same linkage and visibility as
2617 the function template it specializes. */
2618 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2619 if (! TREE_PUBLIC (decl))
2621 DECL_INTERFACE_KNOWN (decl) = 1;
2622 DECL_NOT_REALLY_EXTERN (decl) = 1;
2624 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2625 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2627 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2628 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2632 /* If DECL is a friend declaration, declared using an
2633 unqualified name, the namespace associated with DECL may
2634 have been set incorrectly. For example, in:
2636 template <typename T> void f(T);
2638 struct S { friend void f<int>(int); }
2641 we will have set the DECL_CONTEXT for the friend
2642 declaration to N, rather than to the global namespace. */
2643 if (DECL_NAMESPACE_SCOPE_P (decl))
2644 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2646 if (is_friend && !have_def)
2647 /* This is not really a declaration of a specialization.
2648 It's just the name of an instantiation. But, it's not
2649 a request for an instantiation, either. */
2650 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2651 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2652 /* This is indeed a specialization. In case of constructors
2653 and destructors, we need in-charge and not-in-charge
2654 versions in V3 ABI. */
2655 clone_function_decl (decl, /*update_method_vec_p=*/0);
2657 /* Register this specialization so that we can find it
2659 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2666 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2667 parameters. These are represented in the same format used for
2668 DECL_TEMPLATE_PARMS. */
2671 comp_template_parms (const_tree parms1, const_tree parms2)
2676 if (parms1 == parms2)
2679 for (p1 = parms1, p2 = parms2;
2680 p1 != NULL_TREE && p2 != NULL_TREE;
2681 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2683 tree t1 = TREE_VALUE (p1);
2684 tree t2 = TREE_VALUE (p2);
2687 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2688 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2690 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2693 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2695 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2696 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2698 /* If either of the template parameters are invalid, assume
2699 they match for the sake of error recovery. */
2700 if (parm1 == error_mark_node || parm2 == error_mark_node)
2703 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2706 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2707 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2708 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2710 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2715 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2716 /* One set of parameters has more parameters lists than the
2723 /* Determine whether PARM is a parameter pack. */
2726 template_parameter_pack_p (const_tree parm)
2728 /* Determine if we have a non-type template parameter pack. */
2729 if (TREE_CODE (parm) == PARM_DECL)
2730 return (DECL_TEMPLATE_PARM_P (parm)
2731 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2733 /* If this is a list of template parameters, we could get a
2734 TYPE_DECL or a TEMPLATE_DECL. */
2735 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2736 parm = TREE_TYPE (parm);
2738 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2739 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2740 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2743 /* Determine if T is a function parameter pack. */
2746 function_parameter_pack_p (const_tree t)
2748 if (t && TREE_CODE (t) == PARM_DECL)
2749 return FUNCTION_PARAMETER_PACK_P (t);
2753 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2754 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2757 get_function_template_decl (const_tree primary_func_tmpl_inst)
2759 if (! primary_func_tmpl_inst
2760 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2761 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2764 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2767 /* Return true iff the function parameter PARAM_DECL was expanded
2768 from the function parameter pack PACK. */
2771 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2773 if (DECL_ARTIFICIAL (param_decl)
2774 || !function_parameter_pack_p (pack))
2777 /* The parameter pack and its pack arguments have the same
2779 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2782 /* Determine whether ARGS describes a variadic template args list,
2783 i.e., one that is terminated by a template argument pack. */
2786 template_args_variadic_p (tree args)
2791 if (args == NULL_TREE)
2794 args = INNERMOST_TEMPLATE_ARGS (args);
2795 nargs = TREE_VEC_LENGTH (args);
2800 last_parm = TREE_VEC_ELT (args, nargs - 1);
2802 return ARGUMENT_PACK_P (last_parm);
2805 /* Generate a new name for the parameter pack name NAME (an
2806 IDENTIFIER_NODE) that incorporates its */
2809 make_ith_pack_parameter_name (tree name, int i)
2811 /* Munge the name to include the parameter index. */
2812 #define NUMBUF_LEN 128
2813 char numbuf[NUMBUF_LEN];
2817 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2818 newname_len = IDENTIFIER_LENGTH (name)
2819 + strlen (numbuf) + 2;
2820 newname = (char*)alloca (newname_len);
2821 snprintf (newname, newname_len,
2822 "%s#%i", IDENTIFIER_POINTER (name), i);
2823 return get_identifier (newname);
2826 /* Return true if T is a primary function
2827 or class template instantiation. */
2830 primary_template_instantiation_p (const_tree t)
2835 if (TREE_CODE (t) == FUNCTION_DECL)
2836 return DECL_LANG_SPECIFIC (t)
2837 && DECL_TEMPLATE_INSTANTIATION (t)
2838 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2839 else if (CLASS_TYPE_P (t))
2840 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2841 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2845 /* Return true if PARM is a template template parameter. */
2848 template_template_parameter_p (const_tree parm)
2850 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2853 /* Return the template parameters of T if T is a
2854 primary template instantiation, NULL otherwise. */
2857 get_primary_template_innermost_parameters (const_tree t)
2859 tree parms = NULL, template_info = NULL;
2861 if ((template_info = get_template_info (t))
2862 && primary_template_instantiation_p (t))
2863 parms = INNERMOST_TEMPLATE_PARMS
2864 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2869 /* Return the template parameters of the LEVELth level from the full list
2870 of template parameters PARMS. */
2873 get_template_parms_at_level (tree parms, int level)
2877 || TREE_CODE (parms) != TREE_LIST
2878 || level > TMPL_PARMS_DEPTH (parms))
2881 for (p = parms; p; p = TREE_CHAIN (p))
2882 if (TMPL_PARMS_DEPTH (p) == level)
2888 /* Returns the template arguments of T if T is a template instantiation,
2892 get_template_innermost_arguments (const_tree t)
2894 tree args = NULL, template_info = NULL;
2896 if ((template_info = get_template_info (t))
2897 && TI_ARGS (template_info))
2898 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2903 /* Return the argument pack elements of T if T is a template argument pack,
2907 get_template_argument_pack_elems (const_tree t)
2909 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2910 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2913 return ARGUMENT_PACK_ARGS (t);
2916 /* Structure used to track the progress of find_parameter_packs_r. */
2917 struct find_parameter_pack_data
2919 /* TREE_LIST that will contain all of the parameter packs found by
2921 tree* parameter_packs;
2923 /* Set of AST nodes that have been visited by the traversal. */
2924 struct pointer_set_t *visited;
2927 /* Identifies all of the argument packs that occur in a template
2928 argument and appends them to the TREE_LIST inside DATA, which is a
2929 find_parameter_pack_data structure. This is a subroutine of
2930 make_pack_expansion and uses_parameter_packs. */
2932 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2935 struct find_parameter_pack_data* ppd =
2936 (struct find_parameter_pack_data*)data;
2937 bool parameter_pack_p = false;
2939 /* Identify whether this is a parameter pack or not. */
2940 switch (TREE_CODE (t))
2942 case TEMPLATE_PARM_INDEX:
2943 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2944 parameter_pack_p = true;
2947 case TEMPLATE_TYPE_PARM:
2948 case TEMPLATE_TEMPLATE_PARM:
2949 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2950 parameter_pack_p = true;
2954 if (FUNCTION_PARAMETER_PACK_P (t))
2956 /* We don't want to walk into the type of a PARM_DECL,
2957 because we don't want to see the type parameter pack. */
2959 parameter_pack_p = true;
2964 /* Not a parameter pack. */
2968 if (parameter_pack_p)
2970 /* Add this parameter pack to the list. */
2971 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2975 cp_walk_tree (&TYPE_CONTEXT (t),
2976 &find_parameter_packs_r, ppd, ppd->visited);
2978 /* This switch statement will return immediately if we don't find a
2980 switch (TREE_CODE (t))
2982 case TEMPLATE_PARM_INDEX:
2985 case BOUND_TEMPLATE_TEMPLATE_PARM:
2986 /* Check the template itself. */
2987 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2988 &find_parameter_packs_r, ppd, ppd->visited);
2989 /* Check the template arguments. */
2990 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2995 case TEMPLATE_TYPE_PARM:
2996 case TEMPLATE_TEMPLATE_PARM:
3003 if (TYPE_PTRMEMFUNC_P (t))
3009 if (TYPE_TEMPLATE_INFO (t))
3010 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3011 &find_parameter_packs_r, ppd, ppd->visited);
3017 cp_walk_tree (&TREE_TYPE (t),
3018 &find_parameter_packs_r, ppd, ppd->visited);
3022 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3027 case TYPE_PACK_EXPANSION:
3028 case EXPR_PACK_EXPANSION:
3033 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3038 case IDENTIFIER_NODE:
3039 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3051 /* Determines if the expression or type T uses any parameter packs. */
3053 uses_parameter_packs (tree t)
3055 tree parameter_packs = NULL_TREE;
3056 struct find_parameter_pack_data ppd;
3057 ppd.parameter_packs = ¶meter_packs;
3058 ppd.visited = pointer_set_create ();
3059 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3060 pointer_set_destroy (ppd.visited);
3061 return parameter_packs != NULL_TREE;
3064 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3065 representation a base-class initializer into a parameter pack
3066 expansion. If all goes well, the resulting node will be an
3067 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3070 make_pack_expansion (tree arg)
3073 tree parameter_packs = NULL_TREE;
3074 bool for_types = false;
3075 struct find_parameter_pack_data ppd;
3077 if (!arg || arg == error_mark_node)
3080 if (TREE_CODE (arg) == TREE_LIST)
3082 /* The only time we will see a TREE_LIST here is for a base
3083 class initializer. In this case, the TREE_PURPOSE will be a
3084 _TYPE node (representing the base class expansion we're
3085 initializing) and the TREE_VALUE will be a TREE_LIST
3086 containing the initialization arguments.
3088 The resulting expansion looks somewhat different from most
3089 expansions. Rather than returning just one _EXPANSION, we
3090 return a TREE_LIST whose TREE_PURPOSE is a
3091 TYPE_PACK_EXPANSION containing the bases that will be
3092 initialized. The TREE_VALUE will be identical to the
3093 original TREE_VALUE, which is a list of arguments that will
3094 be passed to each base. We do not introduce any new pack
3095 expansion nodes into the TREE_VALUE (although it is possible
3096 that some already exist), because the TREE_PURPOSE and
3097 TREE_VALUE all need to be expanded together with the same
3098 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3099 resulting TREE_PURPOSE will mention the parameter packs in
3100 both the bases and the arguments to the bases. */
3103 tree parameter_packs = NULL_TREE;
3105 /* Determine which parameter packs will be used by the base
3107 ppd.visited = pointer_set_create ();
3108 ppd.parameter_packs = ¶meter_packs;
3109 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3112 if (parameter_packs == NULL_TREE)
3114 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3115 pointer_set_destroy (ppd.visited);
3116 return error_mark_node;
3119 if (TREE_VALUE (arg) != void_type_node)
3121 /* Collect the sets of parameter packs used in each of the
3122 initialization arguments. */
3123 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3125 /* Determine which parameter packs will be expanded in this
3127 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3132 pointer_set_destroy (ppd.visited);
3134 /* Create the pack expansion type for the base type. */
3135 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3136 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3137 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3139 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3140 they will rarely be compared to anything. */
3141 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3143 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3146 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3149 /* Build the PACK_EXPANSION_* node. */
3151 ? cxx_make_type (TYPE_PACK_EXPANSION)
3152 : make_node (EXPR_PACK_EXPANSION);
3153 SET_PACK_EXPANSION_PATTERN (result, arg);
3154 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3156 /* Propagate type and const-expression information. */
3157 TREE_TYPE (result) = TREE_TYPE (arg);
3158 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3161 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3162 they will rarely be compared to anything. */
3163 SET_TYPE_STRUCTURAL_EQUALITY (result);
3165 /* Determine which parameter packs will be expanded. */
3166 ppd.parameter_packs = ¶meter_packs;
3167 ppd.visited = pointer_set_create ();
3168 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3169 pointer_set_destroy (ppd.visited);
3171 /* Make sure we found some parameter packs. */
3172 if (parameter_packs == NULL_TREE)
3175 error ("expansion pattern %<%T%> contains no argument packs", arg);
3177 error ("expansion pattern %<%E%> contains no argument packs", arg);
3178 return error_mark_node;
3180 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3185 /* Checks T for any "bare" parameter packs, which have not yet been
3186 expanded, and issues an error if any are found. This operation can
3187 only be done on full expressions or types (e.g., an expression
3188 statement, "if" condition, etc.), because we could have expressions like:
3190 foo(f(g(h(args)))...)
3192 where "args" is a parameter pack. check_for_bare_parameter_packs
3193 should not be called for the subexpressions args, h(args),
3194 g(h(args)), or f(g(h(args))), because we would produce erroneous
3197 Returns TRUE and emits an error if there were bare parameter packs,
3198 returns FALSE otherwise. */
3200 check_for_bare_parameter_packs (tree t)
3202 tree parameter_packs = NULL_TREE;
3203 struct find_parameter_pack_data ppd;
3205 if (!processing_template_decl || !t || t == error_mark_node)
3208 if (TREE_CODE (t) == TYPE_DECL)
3211 ppd.parameter_packs = ¶meter_packs;
3212 ppd.visited = pointer_set_create ();
3213 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3214 pointer_set_destroy (ppd.visited);
3216 if (parameter_packs)
3218 error ("parameter packs not expanded with %<...%>:");
3219 while (parameter_packs)
3221 tree pack = TREE_VALUE (parameter_packs);
3222 tree name = NULL_TREE;
3224 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3225 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3226 name = TYPE_NAME (pack);
3227 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3228 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3230 name = DECL_NAME (pack);
3233 inform (input_location, " %qD", name);
3235 inform (input_location, " <anonymous>");
3237 parameter_packs = TREE_CHAIN (parameter_packs);
3246 /* Expand any parameter packs that occur in the template arguments in
3249 expand_template_argument_pack (tree args)
3251 tree result_args = NULL_TREE;
3252 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3253 int num_result_args = -1;
3254 int non_default_args_count = -1;
3256 /* First, determine if we need to expand anything, and the number of
3257 slots we'll need. */
3258 for (in_arg = 0; in_arg < nargs; ++in_arg)
3260 tree arg = TREE_VEC_ELT (args, in_arg);
3261 if (arg == NULL_TREE)
3263 if (ARGUMENT_PACK_P (arg))
3265 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3266 if (num_result_args < 0)
3267 num_result_args = in_arg + num_packed;
3269 num_result_args += num_packed;
3273 if (num_result_args >= 0)
3278 /* If no expansion is necessary, we're done. */
3279 if (num_result_args < 0)
3282 /* Expand arguments. */
3283 result_args = make_tree_vec (num_result_args);
3284 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3285 non_default_args_count =
3286 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3287 for (in_arg = 0; in_arg < nargs; ++in_arg)
3289 tree arg = TREE_VEC_ELT (args, in_arg);
3290 if (ARGUMENT_PACK_P (arg))
3292 tree packed = ARGUMENT_PACK_ARGS (arg);
3293 int i, num_packed = TREE_VEC_LENGTH (packed);
3294 for (i = 0; i < num_packed; ++i, ++out_arg)
3295 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3296 if (non_default_args_count > 0)
3297 non_default_args_count += num_packed;
3301 TREE_VEC_ELT (result_args, out_arg) = arg;
3305 if (non_default_args_count >= 0)
3306 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3310 /* Checks if DECL shadows a template parameter.
3312 [temp.local]: A template-parameter shall not be redeclared within its
3313 scope (including nested scopes).
3315 Emits an error and returns TRUE if the DECL shadows a parameter,
3316 returns FALSE otherwise. */
3319 check_template_shadow (tree decl)
3323 /* If we're not in a template, we can't possibly shadow a template
3325 if (!current_template_parms)
3328 /* Figure out what we're shadowing. */
3329 if (TREE_CODE (decl) == OVERLOAD)
3330 decl = OVL_CURRENT (decl);
3331 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3333 /* If there's no previous binding for this name, we're not shadowing
3334 anything, let alone a template parameter. */
3338 /* If we're not shadowing a template parameter, we're done. Note
3339 that OLDDECL might be an OVERLOAD (or perhaps even an
3340 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3342 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3345 /* We check for decl != olddecl to avoid bogus errors for using a
3346 name inside a class. We check TPFI to avoid duplicate errors for
3347 inline member templates. */
3349 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3352 error ("declaration of %q+#D", decl);
3353 error (" shadows template parm %q+#D", olddecl);
3357 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3358 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3359 template parameters. */
3362 build_template_parm_index (int index,
3369 tree t = make_node (TEMPLATE_PARM_INDEX);
3370 TEMPLATE_PARM_IDX (t) = index;
3371 TEMPLATE_PARM_LEVEL (t) = level;
3372 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3373 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3374 TEMPLATE_PARM_DECL (t) = decl;
3375 TREE_TYPE (t) = type;
3376 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3377 TREE_READONLY (t) = TREE_READONLY (decl);
3382 /* Find the canonical type parameter for the given template type
3383 parameter. Returns the canonical type parameter, which may be TYPE
3384 if no such parameter existed. */
3387 canonical_type_parameter (tree type)
3390 int idx = TEMPLATE_TYPE_IDX (type);
3391 if (!canonical_template_parms)
3392 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3394 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3395 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3397 list = VEC_index (tree, canonical_template_parms, idx);
3398 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3399 list = TREE_CHAIN (list);
3402 return TREE_VALUE (list);
3405 VEC_replace(tree, canonical_template_parms, idx,
3406 tree_cons (NULL_TREE, type,
3407 VEC_index (tree, canonical_template_parms, idx)));
3412 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3413 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3414 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3415 new one is created. */
3418 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3419 tsubst_flags_t complain)
3421 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3422 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3423 != TEMPLATE_PARM_LEVEL (index) - levels)
3424 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3426 tree orig_decl = TEMPLATE_PARM_DECL (index);
3429 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3430 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3431 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3432 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3433 DECL_ARTIFICIAL (decl) = 1;
3434 SET_DECL_TEMPLATE_PARM_P (decl);
3436 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3437 TEMPLATE_PARM_LEVEL (index) - levels,
3438 TEMPLATE_PARM_ORIG_LEVEL (index),
3439 TEMPLATE_PARM_NUM_SIBLINGS (index),
3441 TEMPLATE_PARM_DESCENDANTS (index) = t;
3442 TEMPLATE_PARM_PARAMETER_PACK (t)
3443 = TEMPLATE_PARM_PARAMETER_PACK (index);
3445 /* Template template parameters need this. */
3446 if (TREE_CODE (decl) == TEMPLATE_DECL)
3447 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3448 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3452 return TEMPLATE_PARM_DESCENDANTS (index);
3455 /* Process information from new template parameter PARM and append it
3456 to the LIST being built. This new parameter is a non-type
3457 parameter iff IS_NON_TYPE is true. This new parameter is a
3458 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3459 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3460 parameter list PARM belongs to. This is used used to create a
3461 proper canonical type for the type of PARM that is to be created,
3462 iff PARM is a type. If the size is not known, this parameter shall
3466 process_template_parm (tree list, location_t parm_loc, tree parm,
3467 bool is_non_type, bool is_parameter_pack,
3468 unsigned num_template_parms)
3475 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3476 defval = TREE_PURPOSE (parm);
3480 tree p = tree_last (list);
3482 if (p && TREE_VALUE (p) != error_mark_node)
3485 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3486 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3488 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3498 parm = TREE_VALUE (parm);
3500 SET_DECL_TEMPLATE_PARM_P (parm);
3502 if (TREE_TYPE (parm) == error_mark_node)
3504 err_parm_list = build_tree_list (defval, parm);
3505 TREE_VALUE (err_parm_list) = error_mark_node;
3506 return chainon (list, err_parm_list);
3512 The top-level cv-qualifiers on the template-parameter are
3513 ignored when determining its type. */
3514 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3515 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3517 err_parm_list = build_tree_list (defval, parm);
3518 TREE_VALUE (err_parm_list) = error_mark_node;
3519 return chainon (list, err_parm_list);
3522 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3524 /* This template parameter is not a parameter pack, but it
3525 should be. Complain about "bare" parameter packs. */
3526 check_for_bare_parameter_packs (TREE_TYPE (parm));
3528 /* Recover by calling this a parameter pack. */
3529 is_parameter_pack = true;
3533 /* A template parameter is not modifiable. */
3534 TREE_CONSTANT (parm) = 1;
3535 TREE_READONLY (parm) = 1;
3536 decl = build_decl (parm_loc,
3537 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3538 TREE_CONSTANT (decl) = 1;
3539 TREE_READONLY (decl) = 1;
3540 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3541 = build_template_parm_index (idx, processing_template_decl,
3542 processing_template_decl,
3544 decl, TREE_TYPE (parm));
3546 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3547 = is_parameter_pack;
3552 parm = TREE_VALUE (TREE_VALUE (parm));
3554 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3556 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3557 /* This is for distinguishing between real templates and template
3558 template parameters */
3559 TREE_TYPE (parm) = t;
3560 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3565 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3566 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3567 decl = build_decl (parm_loc,
3568 TYPE_DECL, parm, t);
3571 TYPE_NAME (t) = decl;
3572 TYPE_STUB_DECL (t) = decl;
3574 TEMPLATE_TYPE_PARM_INDEX (t)
3575 = build_template_parm_index (idx, processing_template_decl,
3576 processing_template_decl,
3578 decl, TREE_TYPE (parm));
3579 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3580 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3582 DECL_ARTIFICIAL (decl) = 1;
3583 SET_DECL_TEMPLATE_PARM_P (decl);
3585 parm = build_tree_list (defval, parm);
3586 return chainon (list, parm);
3589 /* The end of a template parameter list has been reached. Process the
3590 tree list into a parameter vector, converting each parameter into a more
3591 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3595 end_template_parm_list (tree parms)
3599 tree saved_parmlist = make_tree_vec (list_length (parms));
3601 current_template_parms
3602 = tree_cons (size_int (processing_template_decl),
3603 saved_parmlist, current_template_parms);
3605 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3607 next = TREE_CHAIN (parm);
3608 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3609 TREE_CHAIN (parm) = NULL_TREE;
3612 --processing_template_parmlist;
3614 return saved_parmlist;
3617 /* Create a new type almost identical to TYPE but which has the
3618 following differences:
3620 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3621 template sibling parameters of T.
3623 2/ T has a new canonical type that matches the new number
3626 3/ From now on, T is going to be what lookups referring to the
3627 name of TYPE will return. No lookup should return TYPE anymore.
3629 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3631 This is a subroutine of fixup_template_parms. */
3634 fixup_template_type_parm_type (tree type, int num_parms)
3636 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3638 /* This is the decl which name is inserted into the symbol table for
3639 the template parm type. So whenever we lookup the type name, this
3640 is the DECL we get. */
3643 /* Do not fix up the type twice. */
3644 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3647 t = copy_type (type);
3648 decl = TYPE_NAME (t);
3650 TYPE_MAIN_VARIANT (t) = t;
3651 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3652 TYPE_POINTER_TO (t) = 0;
3653 TYPE_REFERENCE_TO (t) = 0;
3655 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3656 TEMPLATE_PARM_LEVEL (orig_idx),
3657 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3660 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3661 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3662 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3664 TYPE_STUB_DECL (t) = decl;
3665 TEMPLATE_TYPE_DECL (t) = decl;
3666 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3667 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3669 /* Update the type associated to the type name stored in the symbol
3670 table. Now, whenever the type name is looked up, the resulting
3671 type is properly fixed up. */
3672 TREE_TYPE (decl) = t;
3674 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3679 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3680 identical to I, but that is fixed up as to:
3682 1/ carry the number of sibling parms (NUM_PARMS) of the template
3683 parm represented by I.
3685 2/ replace all references to template parm types declared before I
3686 (in the same template parm list as I) by references to template
3687 parm types contained in ARGS. ARGS should contain the list of
3688 template parms that have been fixed up so far, in a form suitable
3689 to be passed to tsubst.
3691 This is a subroutine of fixup_template_parms. */
3694 fixup_template_parm_index (tree i, tree args, int num_parms)
3696 tree index, decl, type;
3699 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3700 /* Do not fix up the index twice. */
3701 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3704 decl = TEMPLATE_PARM_DECL (i);
3705 type = TREE_TYPE (decl);
3707 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3708 TEMPLATE_PARM_LEVEL (i),
3709 TEMPLATE_PARM_ORIG_LEVEL (i),
3713 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3714 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3716 type = tsubst (type, args, tf_none, NULL_TREE);
3718 TREE_TYPE (decl) = type;
3719 TREE_TYPE (index) = type;
3725 This is a subroutine of fixup_template_parms.
3727 It computes the canonical type of the type of the template
3728 parameter PARM_DESC and update all references to that type so that
3729 they use the newly computed canonical type. No access check is
3730 performed during the fixup. PARM_DESC is a TREE_LIST which
3731 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3732 default argument of the template parm if any. IDX is the index of
3733 the template parameter, starting at 0. NUM_PARMS is the number of
3734 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3735 TREE_VEC containing the full set of template parameters in a form
3736 suitable to be passed to substs functions as their ARGS
3737 argument. This is what current_template_args returns for a given
3738 template. The innermost vector of args in ARGLIST is the set of
3739 template parms that have been fixed up so far. This function adds
3740 the fixed up parameter into that vector. */
3743 fixup_template_parm (tree parm_desc,
3748 tree parm = TREE_VALUE (parm_desc);
3749 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3751 push_deferring_access_checks (dk_no_check);
3753 if (TREE_CODE (parm) == TYPE_DECL)
3755 /* PARM is a template type parameter. Fix up its type, add
3756 the fixed-up template parm to the vector of fixed-up
3757 template parms so far, and substitute the fixed-up
3758 template parms into the default argument of this
3761 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3762 TREE_TYPE (parm) = t;
3764 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3766 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3768 /* PARM is a template template parameter. This is going to
3770 tree tparms, targs, innermost_args, t;
3773 /* First, fix up the parms of the template template parm
3774 because the parms are involved in defining the new canonical
3775 type of the template template parm. */
3777 /* So we need to substitute the template parm types that have
3778 been fixed up so far into the template parms of this template
3779 template parm. E.g, consider this:
3781 template<class T, template<T u> class TT> class S;
3783 In this case we want to substitute T into the
3784 template parameters of TT.
3786 So let's walk the template parms of PARM here, and
3787 tsubst ARGLIST into into each of the template
3790 /* For this substitution we need to build the full set of
3791 template parameters and use that as arguments for the
3792 tsubsting function. */
3793 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3795 /* This will contain the innermost parms of PARM into which
3796 we have substituted so far. */
3797 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3798 targs = add_to_template_args (arglist, innermost_args);
3799 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3803 parameter = TREE_VEC_ELT (tparms, j);
3805 /* INNERMOST_ARGS needs to have at least the same number
3806 of elements as the index PARAMETER, ortherwise
3807 tsubsting into PARAMETER will result in partially
3808 instantiating it, reducing its tempate parm
3809 level. Let's tactically fill INNERMOST_ARGS for that
3811 TREE_VEC_ELT (innermost_args, j) =
3812 template_parm_to_arg (parameter);
3814 fixup_template_parm (parameter, j,
3815 TREE_VEC_LENGTH (tparms),
3819 /* Now fix up the type of the template template parm. */
3821 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3822 TREE_TYPE (parm) = t;
3824 TREE_VEC_ELT (fixedup_args, idx) =
3825 template_parm_to_arg (parm_desc);
3827 else if (TREE_CODE (parm) == PARM_DECL)
3829 /* PARM is a non-type template parameter. We need to:
3831 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3832 proper number of sibling parameters.
3834 * Make lookups of the template parameter return a reference
3835 to the fixed-up index. No lookup should return references
3836 to the former index anymore.
3838 * Substitute the template parms that got fixed up so far
3840 * into the type of PARM. */
3842 tree index = DECL_INITIAL (parm);
3844 /* PUSHED_DECL is the decl added to the symbol table with
3845 the name of the parameter. E,g:
3847 template<class T, T u> //#0
3848 auto my_function(T t) -> decltype(u); //#1
3850 Here, when looking up u at //#1, we get the decl of u
3851 resulting from the declaration in #0. This is what
3852 PUSHED_DECL is. We need to replace the reference to the
3853 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3854 fixed-up TEMPLATE_PARM_INDEX. */
3855 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3857 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3858 fixup the type of PUSHED_DECL as well and luckily
3859 fixup_template_parm_index does it for us too. */
3860 tree fixed_up_index =
3861 fixup_template_parm_index (index, arglist, num_parms);
3863 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3865 /* Add this fixed up PARM to the template parms we've fixed
3866 up so far and use that to substitute the fixed-up
3867 template parms into the type of PARM. */
3868 TREE_VEC_ELT (fixedup_args, idx) =
3869 template_parm_to_arg (parm_desc);
3870 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3871 tf_none, NULL_TREE);
3874 TREE_PURPOSE (parm_desc) =
3875 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3876 arglist, tf_none, parm);
3878 pop_deferring_access_checks ();
3881 /* Walk the current template parms and properly compute the canonical
3882 types of the dependent types created during
3883 cp_parser_template_parameter_list. */
3886 fixup_template_parms (void)
3893 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3894 if (parameter_vec == NULL_TREE)
3897 num_parms = TREE_VEC_LENGTH (parameter_vec);
3899 /* This vector contains the current innermost template parms that
3900 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3901 to be passed to tsubst* functions as their ARGS argument. */
3902 fixedup_args = make_tree_vec (num_parms);
3904 /* This vector contains the full set of template parms in a form
3905 suitable to be passed to substs functions as their ARGS
3907 arglist = current_template_args ();
3908 arglist = add_outermost_template_args (arglist, fixedup_args);
3910 /* Let's do the proper fixup now. */
3911 for (i = 0; i < num_parms; ++i)
3912 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3913 i, num_parms, arglist);
3916 /* end_template_decl is called after a template declaration is seen. */
3919 end_template_decl (void)
3921 reset_specialization ();
3923 if (! processing_template_decl)
3926 /* This matches the pushlevel in begin_template_parm_list. */
3929 --processing_template_decl;
3930 current_template_parms = TREE_CHAIN (current_template_parms);
3933 /* Takes a TREE_LIST representing a template parameter and convert it
3934 into an argument suitable to be passed to the type substitution
3935 functions. Note that If the TREE_LIST contains an error_mark
3936 node, the returned argument is error_mark_node. */
3939 template_parm_to_arg (tree t)
3943 || TREE_CODE (t) != TREE_LIST)
3946 if (error_operand_p (TREE_VALUE (t)))
3947 return error_mark_node;
3951 if (TREE_CODE (t) == TYPE_DECL
3952 || TREE_CODE (t) == TEMPLATE_DECL)
3956 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3958 /* Turn this argument into a TYPE_ARGUMENT_PACK
3959 with a single element, which expands T. */
3960 tree vec = make_tree_vec (1);
3961 #ifdef ENABLE_CHECKING
3962 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3963 (vec, TREE_VEC_LENGTH (vec));
3965 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3967 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3968 SET_ARGUMENT_PACK_ARGS (t, vec);
3973 t = DECL_INITIAL (t);
3975 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3977 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3978 with a single element, which expands T. */
3979 tree vec = make_tree_vec (1);
3980 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3981 #ifdef ENABLE_CHECKING
3982 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3983 (vec, TREE_VEC_LENGTH (vec));
3985 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3987 t = make_node (NONTYPE_ARGUMENT_PACK);
3988 SET_ARGUMENT_PACK_ARGS (t, vec);
3989 TREE_TYPE (t) = type;
3995 /* Within the declaration of a template, return all levels of template
3996 parameters that apply. The template parameters are represented as
3997 a TREE_VEC, in the form documented in cp-tree.h for template
4001 current_template_args (void)
4004 tree args = NULL_TREE;
4005 int length = TMPL_PARMS_DEPTH (current_template_parms);
4008 /* If there is only one level of template parameters, we do not
4009 create a TREE_VEC of TREE_VECs. Instead, we return a single
4010 TREE_VEC containing the arguments. */
4012 args = make_tree_vec (length);
4014 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4016 tree a = copy_node (TREE_VALUE (header));
4019 TREE_TYPE (a) = NULL_TREE;
4020 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4021 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4023 #ifdef ENABLE_CHECKING
4024 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4028 TREE_VEC_ELT (args, --l) = a;
4033 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4034 /* This can happen for template parms of a template template
4037 template<template<class T, class U> class TT> struct S;
4039 Consider the level of the parms of TT; T and U both have
4040 level 2; TT has no template parm of level 1. So in this case
4041 the first element of full_template_args is NULL_TREE. If we
4042 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4043 of 2. This will make tsubst wrongly consider that T and U
4044 have level 1. Instead, let's create a dummy vector as the
4045 first element of full_template_args so that TMPL_ARG_DEPTH
4046 returns the correct depth for args. */
4047 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4051 /* Update the declared TYPE by doing any lookups which were thought to be
4052 dependent, but are not now that we know the SCOPE of the declarator. */
4055 maybe_update_decl_type (tree orig_type, tree scope)
4057 tree type = orig_type;
4059 if (type == NULL_TREE)
4062 if (TREE_CODE (orig_type) == TYPE_DECL)
4063 type = TREE_TYPE (type);
4065 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4066 && dependent_type_p (type)
4067 /* Don't bother building up the args in this case. */
4068 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4070 /* tsubst in the args corresponding to the template parameters,
4071 including auto if present. Most things will be unchanged, but
4072 make_typename_type and tsubst_qualified_id will resolve
4073 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4074 tree args = current_template_args ();
4075 tree auto_node = type_uses_auto (type);
4079 tree auto_vec = make_tree_vec (1);
4080 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4081 args = add_to_template_args (args, auto_vec);
4083 pushed = push_scope (scope);
4084 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4089 if (type == error_mark_node)
4092 if (TREE_CODE (orig_type) == TYPE_DECL)
4094 if (same_type_p (type, TREE_TYPE (orig_type)))
4097 type = TYPE_NAME (type);
4102 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4103 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4104 a member template. Used by push_template_decl below. */
4107 build_template_decl (tree decl, tree parms, bool member_template_p)
4109 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4110 DECL_TEMPLATE_PARMS (tmpl) = parms;
4111 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4112 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4117 struct template_parm_data
4119 /* The level of the template parameters we are currently
4123 /* The index of the specialization argument we are currently
4127 /* An array whose size is the number of template parameters. The
4128 elements are nonzero if the parameter has been used in any one
4129 of the arguments processed so far. */
4132 /* An array whose size is the number of template arguments. The
4133 elements are nonzero if the argument makes use of template
4134 parameters of this level. */
4135 int* arg_uses_template_parms;
4138 /* Subroutine of push_template_decl used to see if each template
4139 parameter in a partial specialization is used in the explicit
4140 argument list. If T is of the LEVEL given in DATA (which is
4141 treated as a template_parm_data*), then DATA->PARMS is marked
4145 mark_template_parm (tree t, void* data)
4149 struct template_parm_data* tpd = (struct template_parm_data*) data;
4151 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4153 level = TEMPLATE_PARM_LEVEL (t);
4154 idx = TEMPLATE_PARM_IDX (t);
4158 level = TEMPLATE_TYPE_LEVEL (t);
4159 idx = TEMPLATE_TYPE_IDX (t);
4162 if (level == tpd->level)
4164 tpd->parms[idx] = 1;
4165 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4168 /* Return zero so that for_each_template_parm will continue the
4169 traversal of the tree; we want to mark *every* template parm. */
4173 /* Process the partial specialization DECL. */
4176 process_partial_specialization (tree decl)
4178 tree type = TREE_TYPE (decl);
4179 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4180 tree specargs = CLASSTYPE_TI_ARGS (type);
4181 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4182 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4185 int nargs = TREE_VEC_LENGTH (inner_args);
4188 bool did_error_intro = false;
4189 struct template_parm_data tpd;
4190 struct template_parm_data tpd2;
4192 gcc_assert (current_template_parms);
4194 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4195 ntparms = TREE_VEC_LENGTH (inner_parms);
4197 /* We check that each of the template parameters given in the
4198 partial specialization is used in the argument list to the
4199 specialization. For example:
4201 template <class T> struct S;
4202 template <class T> struct S<T*>;
4204 The second declaration is OK because `T*' uses the template
4205 parameter T, whereas
4207 template <class T> struct S<int>;
4209 is no good. Even trickier is:
4220 The S2<T> declaration is actually invalid; it is a
4221 full-specialization. Of course,
4224 struct S2<T (*)(U)>;
4226 or some such would have been OK. */
4227 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4228 tpd.parms = XALLOCAVEC (int, ntparms);
4229 memset (tpd.parms, 0, sizeof (int) * ntparms);
4231 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4232 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4233 for (i = 0; i < nargs; ++i)
4235 tpd.current_arg = i;
4236 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4237 &mark_template_parm,
4240 /*include_nondeduced_p=*/false);
4242 for (i = 0; i < ntparms; ++i)
4243 if (tpd.parms[i] == 0)
4245 /* One of the template parms was not used in the
4247 if (!did_error_intro)
4249 error ("template parameters not used in partial specialization:");
4250 did_error_intro = true;
4253 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4256 if (did_error_intro)
4257 return error_mark_node;
4259 /* [temp.class.spec]
4261 The argument list of the specialization shall not be identical to
4262 the implicit argument list of the primary template. */
4263 if (comp_template_args
4265 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4267 error ("partial specialization %qT does not specialize any template arguments", type);
4269 /* [temp.class.spec]
4271 A partially specialized non-type argument expression shall not
4272 involve template parameters of the partial specialization except
4273 when the argument expression is a simple identifier.
4275 The type of a template parameter corresponding to a specialized
4276 non-type argument shall not be dependent on a parameter of the
4279 Also, we verify that pack expansions only occur at the
4280 end of the argument list. */
4281 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4283 for (i = 0; i < nargs; ++i)
4285 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4286 tree arg = TREE_VEC_ELT (inner_args, i);
4287 tree packed_args = NULL_TREE;
4290 if (ARGUMENT_PACK_P (arg))
4292 /* Extract the arguments from the argument pack. We'll be
4293 iterating over these in the following loop. */
4294 packed_args = ARGUMENT_PACK_ARGS (arg);
4295 len = TREE_VEC_LENGTH (packed_args);
4298 for (j = 0; j < len; j++)
4301 /* Get the Jth argument in the parameter pack. */
4302 arg = TREE_VEC_ELT (packed_args, j);
4304 if (PACK_EXPANSION_P (arg))
4306 /* Pack expansions must come at the end of the
4308 if ((packed_args && j < len - 1)
4309 || (!packed_args && i < nargs - 1))
4311 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4312 error ("parameter pack argument %qE must be at the "
4313 "end of the template argument list", arg);
4315 error ("parameter pack argument %qT must be at the "
4316 "end of the template argument list", arg);
4320 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4321 /* We only care about the pattern. */
4322 arg = PACK_EXPANSION_PATTERN (arg);
4324 if (/* These first two lines are the `non-type' bit. */
4326 && TREE_CODE (arg) != TEMPLATE_DECL
4327 /* This next line is the `argument expression is not just a
4328 simple identifier' condition and also the `specialized
4329 non-type argument' bit. */
4330 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4332 if ((!packed_args && tpd.arg_uses_template_parms[i])
4333 || (packed_args && uses_template_parms (arg)))
4334 error ("template argument %qE involves template parameter(s)",
4338 /* Look at the corresponding template parameter,
4339 marking which template parameters its type depends
4341 tree type = TREE_TYPE (parm);
4345 /* We haven't yet initialized TPD2. Do so now. */
4346 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4347 /* The number of parameters here is the number in the
4348 main template, which, as checked in the assertion
4350 tpd2.parms = XALLOCAVEC (int, nargs);
4352 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4355 /* Mark the template parameters. But this time, we're
4356 looking for the template parameters of the main
4357 template, not in the specialization. */
4358 tpd2.current_arg = i;
4359 tpd2.arg_uses_template_parms[i] = 0;
4360 memset (tpd2.parms, 0, sizeof (int) * nargs);
4361 for_each_template_parm (type,
4362 &mark_template_parm,
4365 /*include_nondeduced_p=*/false);
4367 if (tpd2.arg_uses_template_parms [i])
4369 /* The type depended on some template parameters.
4370 If they are fully specialized in the
4371 specialization, that's OK. */
4374 for (j = 0; j < nargs; ++j)
4375 if (tpd2.parms[j] != 0
4376 && tpd.arg_uses_template_parms [j])
4379 error_n (input_location, count,
4380 "type %qT of template argument %qE depends "
4381 "on a template parameter",
4382 "type %qT of template argument %qE depends "
4383 "on template parameters",
4392 /* We should only get here once. */
4393 gcc_assert (!COMPLETE_TYPE_P (type));
4395 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4396 = tree_cons (specargs, inner_parms,
4397 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4398 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4400 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4401 inst = TREE_CHAIN (inst))
4403 tree inst_type = TREE_VALUE (inst);
4404 if (COMPLETE_TYPE_P (inst_type)
4405 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4407 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4408 if (spec && TREE_TYPE (spec) == type)
4409 permerror (input_location,
4410 "partial specialization of %qT after instantiation "
4411 "of %qT", type, inst_type);
4418 /* Check that a template declaration's use of default arguments and
4419 parameter packs is not invalid. Here, PARMS are the template
4420 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4421 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4425 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4426 declaration (but not a definition); 1 indicates a declaration, 2
4427 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4428 emitted for extraneous default arguments.
4430 Returns TRUE if there were no errors found, FALSE otherwise. */
4433 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4434 int is_partial, int is_friend_decl)
4437 int last_level_to_check;
4439 bool no_errors = true;
4443 A default template-argument shall not be specified in a
4444 function template declaration or a function template definition, nor
4445 in the template-parameter-list of the definition of a member of a
4448 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4449 /* You can't have a function template declaration in a local
4450 scope, nor you can you define a member of a class template in a
4454 if (current_class_type
4455 && !TYPE_BEING_DEFINED (current_class_type)
4456 && DECL_LANG_SPECIFIC (decl)
4457 && DECL_DECLARES_FUNCTION_P (decl)
4458 /* If this is either a friend defined in the scope of the class
4459 or a member function. */
4460 && (DECL_FUNCTION_MEMBER_P (decl)
4461 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4462 : DECL_FRIEND_CONTEXT (decl)
4463 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4465 /* And, if it was a member function, it really was defined in
4466 the scope of the class. */
4467 && (!DECL_FUNCTION_MEMBER_P (decl)
4468 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4469 /* We already checked these parameters when the template was
4470 declared, so there's no need to do it again now. This function
4471 was defined in class scope, but we're processing it's body now
4472 that the class is complete. */
4475 /* Core issue 226 (C++0x only): the following only applies to class
4477 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4481 If a template-parameter has a default template-argument, all
4482 subsequent template-parameters shall have a default
4483 template-argument supplied. */
4484 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4486 tree inner_parms = TREE_VALUE (parm_level);
4487 int ntparms = TREE_VEC_LENGTH (inner_parms);
4488 int seen_def_arg_p = 0;
4491 for (i = 0; i < ntparms; ++i)
4493 tree parm = TREE_VEC_ELT (inner_parms, i);
4495 if (parm == error_mark_node)
4498 if (TREE_PURPOSE (parm))
4500 else if (seen_def_arg_p
4501 && !template_parameter_pack_p (TREE_VALUE (parm)))
4503 error ("no default argument for %qD", TREE_VALUE (parm));
4504 /* For better subsequent error-recovery, we indicate that
4505 there should have been a default argument. */
4506 TREE_PURPOSE (parm) = error_mark_node;
4512 /* Don't complain about an enclosing partial
4514 && parm_level == parms
4515 && TREE_CODE (decl) == TYPE_DECL
4517 && template_parameter_pack_p (TREE_VALUE (parm)))
4519 /* A primary class template can only have one
4520 parameter pack, at the end of the template
4523 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4524 error ("parameter pack %qE must be at the end of the"
4525 " template parameter list", TREE_VALUE (parm));
4527 error ("parameter pack %qT must be at the end of the"
4528 " template parameter list",
4529 TREE_TYPE (TREE_VALUE (parm)));
4531 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4539 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4543 /* For an ordinary class template, default template arguments are
4544 allowed at the innermost level, e.g.:
4545 template <class T = int>
4547 but, in a partial specialization, they're not allowed even
4548 there, as we have in [temp.class.spec]:
4550 The template parameter list of a specialization shall not
4551 contain default template argument values.
4553 So, for a partial specialization, or for a function template
4554 (in C++98/C++03), we look at all of them. */
4557 /* But, for a primary class template that is not a partial
4558 specialization we look at all template parameters except the
4560 parms = TREE_CHAIN (parms);
4562 /* Figure out what error message to issue. */
4563 if (is_friend_decl == 2)
4564 msg = G_("default template arguments may not be used in function template "
4565 "friend re-declaration");
4566 else if (is_friend_decl)
4567 msg = G_("default template arguments may not be used in function template "
4568 "friend declarations");
4569 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4570 msg = G_("default template arguments may not be used in function templates "
4571 "without -std=c++0x or -std=gnu++0x");
4572 else if (is_partial)
4573 msg = G_("default template arguments may not be used in "
4574 "partial specializations");
4576 msg = G_("default argument for template parameter for class enclosing %qD");
4578 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4579 /* If we're inside a class definition, there's no need to
4580 examine the parameters to the class itself. On the one
4581 hand, they will be checked when the class is defined, and,
4582 on the other, default arguments are valid in things like:
4583 template <class T = double>
4584 struct S { template <class U> void f(U); };
4585 Here the default argument for `S' has no bearing on the
4586 declaration of `f'. */
4587 last_level_to_check = template_class_depth (current_class_type) + 1;
4589 /* Check everything. */
4590 last_level_to_check = 0;
4592 for (parm_level = parms;
4593 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4594 parm_level = TREE_CHAIN (parm_level))
4596 tree inner_parms = TREE_VALUE (parm_level);
4600 ntparms = TREE_VEC_LENGTH (inner_parms);
4601 for (i = 0; i < ntparms; ++i)
4603 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4606 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4611 if (is_friend_decl == 2)
4618 /* Clear out the default argument so that we are not
4620 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4624 /* At this point, if we're still interested in issuing messages,
4625 they must apply to classes surrounding the object declared. */
4627 msg = G_("default argument for template parameter for class "
4634 /* Worker for push_template_decl_real, called via
4635 for_each_template_parm. DATA is really an int, indicating the
4636 level of the parameters we are interested in. If T is a template
4637 parameter of that level, return nonzero. */
4640 template_parm_this_level_p (tree t, void* data)
4642 int this_level = *(int *)data;
4645 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4646 level = TEMPLATE_PARM_LEVEL (t);
4648 level = TEMPLATE_TYPE_LEVEL (t);
4649 return level == this_level;
4652 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4653 parameters given by current_template_args, or reuses a
4654 previously existing one, if appropriate. Returns the DECL, or an
4655 equivalent one, if it is replaced via a call to duplicate_decls.
4657 If IS_FRIEND is true, DECL is a friend declaration. */
4660 push_template_decl_real (tree decl, bool is_friend)
4668 int new_template_p = 0;
4669 /* True if the template is a member template, in the sense of
4671 bool member_template_p = false;
4673 if (decl == error_mark_node || !current_template_parms)
4674 return error_mark_node;
4676 /* See if this is a partial specialization. */
4677 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4678 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4679 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4681 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4685 /* For a friend, we want the context of the friend function, not
4686 the type of which it is a friend. */
4687 ctx = CP_DECL_CONTEXT (decl);
4688 else if (CP_DECL_CONTEXT (decl)
4689 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4690 /* In the case of a virtual function, we want the class in which
4692 ctx = CP_DECL_CONTEXT (decl);
4694 /* Otherwise, if we're currently defining some class, the DECL
4695 is assumed to be a member of the class. */
4696 ctx = current_scope ();
4698 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4701 if (!DECL_CONTEXT (decl))
4702 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4704 /* See if this is a primary template. */
4705 if (is_friend && ctx)
4706 /* A friend template that specifies a class context, i.e.
4707 template <typename T> friend void A<T>::f();
4711 primary = template_parm_scope_p ();
4715 if (DECL_CLASS_SCOPE_P (decl))
4716 member_template_p = true;
4717 if (TREE_CODE (decl) == TYPE_DECL
4718 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4720 error ("template class without a name");
4721 return error_mark_node;
4723 else if (TREE_CODE (decl) == FUNCTION_DECL)
4725 if (DECL_DESTRUCTOR_P (decl))
4729 A destructor shall not be a member template. */
4730 error ("destructor %qD declared as member template", decl);
4731 return error_mark_node;
4733 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4734 && (!prototype_p (TREE_TYPE (decl))
4735 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4736 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4737 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4738 == void_list_node)))
4740 /* [basic.stc.dynamic.allocation]
4742 An allocation function can be a function
4743 template. ... Template allocation functions shall
4744 have two or more parameters. */
4745 error ("invalid template declaration of %qD", decl);
4746 return error_mark_node;
4749 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4750 && CLASS_TYPE_P (TREE_TYPE (decl)))
4754 error ("template declaration of %q#D", decl);
4755 return error_mark_node;
4759 /* Check to see that the rules regarding the use of default
4760 arguments are not being violated. */
4761 check_default_tmpl_args (decl, current_template_parms,
4762 primary, is_partial, /*is_friend_decl=*/0);
4764 /* Ensure that there are no parameter packs in the type of this
4765 declaration that have not been expanded. */
4766 if (TREE_CODE (decl) == FUNCTION_DECL)
4768 /* Check each of the arguments individually to see if there are
4769 any bare parameter packs. */
4770 tree type = TREE_TYPE (decl);
4771 tree arg = DECL_ARGUMENTS (decl);
4772 tree argtype = TYPE_ARG_TYPES (type);
4774 while (arg && argtype)
4776 if (!FUNCTION_PARAMETER_PACK_P (arg)
4777 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4779 /* This is a PARM_DECL that contains unexpanded parameter
4780 packs. We have already complained about this in the
4781 check_for_bare_parameter_packs call, so just replace
4782 these types with ERROR_MARK_NODE. */
4783 TREE_TYPE (arg) = error_mark_node;
4784 TREE_VALUE (argtype) = error_mark_node;
4787 arg = DECL_CHAIN (arg);
4788 argtype = TREE_CHAIN (argtype);
4791 /* Check for bare parameter packs in the return type and the
4792 exception specifiers. */
4793 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4794 /* Errors were already issued, set return type to int
4795 as the frontend doesn't expect error_mark_node as
4797 TREE_TYPE (type) = integer_type_node;
4798 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4799 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4801 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4803 TREE_TYPE (decl) = error_mark_node;
4804 return error_mark_node;
4808 return process_partial_specialization (decl);
4810 args = current_template_args ();
4813 || TREE_CODE (ctx) == FUNCTION_DECL
4814 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4815 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4817 if (DECL_LANG_SPECIFIC (decl)
4818 && DECL_TEMPLATE_INFO (decl)
4819 && DECL_TI_TEMPLATE (decl))
4820 tmpl = DECL_TI_TEMPLATE (decl);
4821 /* If DECL is a TYPE_DECL for a class-template, then there won't
4822 be DECL_LANG_SPECIFIC. The information equivalent to
4823 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4824 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4825 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4826 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4828 /* Since a template declaration already existed for this
4829 class-type, we must be redeclaring it here. Make sure
4830 that the redeclaration is valid. */
4831 redeclare_class_template (TREE_TYPE (decl),
4832 current_template_parms);
4833 /* We don't need to create a new TEMPLATE_DECL; just use the
4834 one we already had. */
4835 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4839 tmpl = build_template_decl (decl, current_template_parms,
4843 if (DECL_LANG_SPECIFIC (decl)
4844 && DECL_TEMPLATE_SPECIALIZATION (decl))
4846 /* A specialization of a member template of a template
4848 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4849 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4850 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4856 tree a, t, current, parms;
4858 tree tinfo = get_template_info (decl);
4862 error ("template definition of non-template %q#D", decl);
4863 return error_mark_node;
4866 tmpl = TI_TEMPLATE (tinfo);
4868 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4869 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4870 && DECL_TEMPLATE_SPECIALIZATION (decl)
4871 && DECL_MEMBER_TEMPLATE_P (tmpl))
4875 /* The declaration is a specialization of a member
4876 template, declared outside the class. Therefore, the
4877 innermost template arguments will be NULL, so we
4878 replace them with the arguments determined by the
4879 earlier call to check_explicit_specialization. */
4880 args = DECL_TI_ARGS (decl);
4883 = build_template_decl (decl, current_template_parms,
4885 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4886 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4887 DECL_TI_TEMPLATE (decl) = new_tmpl;
4888 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4889 DECL_TEMPLATE_INFO (new_tmpl)
4890 = build_template_info (tmpl, args);
4892 register_specialization (new_tmpl,
4893 most_general_template (tmpl),
4899 /* Make sure the template headers we got make sense. */
4901 parms = DECL_TEMPLATE_PARMS (tmpl);
4902 i = TMPL_PARMS_DEPTH (parms);
4903 if (TMPL_ARGS_DEPTH (args) != i)
4905 error ("expected %d levels of template parms for %q#D, got %d",
4906 i, decl, TMPL_ARGS_DEPTH (args));
4909 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4911 a = TMPL_ARGS_LEVEL (args, i);
4912 t = INNERMOST_TEMPLATE_PARMS (parms);
4914 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4916 if (current == decl)
4917 error ("got %d template parameters for %q#D",
4918 TREE_VEC_LENGTH (a), decl);
4920 error ("got %d template parameters for %q#T",
4921 TREE_VEC_LENGTH (a), current);
4922 error (" but %d required", TREE_VEC_LENGTH (t));
4923 return error_mark_node;
4926 if (current == decl)
4928 else if (current == NULL_TREE)
4929 /* Can happen in erroneous input. */
4932 current = (TYPE_P (current)
4933 ? TYPE_CONTEXT (current)
4934 : DECL_CONTEXT (current));
4937 /* Check that the parms are used in the appropriate qualifying scopes
4938 in the declarator. */
4939 if (!comp_template_args
4941 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4944 template arguments to %qD do not match original template %qD",
4945 decl, DECL_TEMPLATE_RESULT (tmpl));
4946 if (!uses_template_parms (TI_ARGS (tinfo)))
4947 inform (input_location, "use template<> for an explicit specialization");
4948 /* Avoid crash in import_export_decl. */
4949 DECL_INTERFACE_KNOWN (decl) = 1;
4950 return error_mark_node;
4954 DECL_TEMPLATE_RESULT (tmpl) = decl;
4955 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4957 /* Push template declarations for global functions and types. Note
4958 that we do not try to push a global template friend declared in a
4959 template class; such a thing may well depend on the template
4960 parameters of the class. */
4961 if (new_template_p && !ctx
4962 && !(is_friend && template_class_depth (current_class_type) > 0))
4964 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4965 if (tmpl == error_mark_node)
4966 return error_mark_node;
4968 /* Hide template friend classes that haven't been declared yet. */
4969 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4971 DECL_ANTICIPATED (tmpl) = 1;
4972 DECL_FRIEND_P (tmpl) = 1;
4978 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4981 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4982 if (DECL_CONV_FN_P (tmpl))
4984 int depth = TMPL_PARMS_DEPTH (parms);
4986 /* It is a conversion operator. See if the type converted to
4987 depends on innermost template operands. */
4989 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4991 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4994 /* Give template template parms a DECL_CONTEXT of the template
4995 for which they are a parameter. */
4996 parms = INNERMOST_TEMPLATE_PARMS (parms);
4997 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4999 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5000 if (TREE_CODE (parm) == TEMPLATE_DECL)
5001 DECL_CONTEXT (parm) = tmpl;
5005 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5006 back to its most general template. If TMPL is a specialization,
5007 ARGS may only have the innermost set of arguments. Add the missing
5008 argument levels if necessary. */
5009 if (DECL_TEMPLATE_INFO (tmpl))
5010 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5012 info = build_template_info (tmpl, args);
5014 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5015 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5016 else if (DECL_LANG_SPECIFIC (decl))
5017 DECL_TEMPLATE_INFO (decl) = info;
5019 return DECL_TEMPLATE_RESULT (tmpl);
5023 push_template_decl (tree decl)
5025 return push_template_decl_real (decl, false);
5028 /* Called when a class template TYPE is redeclared with the indicated
5029 template PARMS, e.g.:
5031 template <class T> struct S;
5032 template <class T> struct S {}; */
5035 redeclare_class_template (tree type, tree parms)
5041 if (!TYPE_TEMPLATE_INFO (type))
5043 error ("%qT is not a template type", type);
5047 tmpl = TYPE_TI_TEMPLATE (type);
5048 if (!PRIMARY_TEMPLATE_P (tmpl))
5049 /* The type is nested in some template class. Nothing to worry
5050 about here; there are no new template parameters for the nested
5056 error ("template specifiers not specified in declaration of %qD",
5061 parms = INNERMOST_TEMPLATE_PARMS (parms);
5062 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5064 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5066 error_n (input_location, TREE_VEC_LENGTH (parms),
5067 "redeclared with %d template parameter",
5068 "redeclared with %d template parameters",
5069 TREE_VEC_LENGTH (parms));
5070 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5071 "previous declaration %q+D used %d template parameter",
5072 "previous declaration %q+D used %d template parameters",
5073 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5077 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5084 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5085 || TREE_VEC_ELT (parms, i) == error_mark_node)
5088 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5089 if (tmpl_parm == error_mark_node)
5092 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5093 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5094 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5096 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5098 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5099 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5100 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5101 || (TREE_CODE (tmpl_parm) != PARM_DECL
5102 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5103 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5104 || (TREE_CODE (tmpl_parm) == PARM_DECL
5105 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5106 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5108 error ("template parameter %q+#D", tmpl_parm);
5109 error ("redeclared here as %q#D", parm);
5113 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5115 /* We have in [temp.param]:
5117 A template-parameter may not be given default arguments
5118 by two different declarations in the same scope. */
5119 error_at (input_location, "redefinition of default argument for %q#D", parm);
5120 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5121 "original definition appeared here");
5125 if (parm_default != NULL_TREE)
5126 /* Update the previous template parameters (which are the ones
5127 that will really count) with the new default value. */
5128 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5129 else if (tmpl_default != NULL_TREE)
5130 /* Update the new parameters, too; they'll be used as the
5131 parameters for any members. */
5132 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5138 /* Simplify EXPR if it is a non-dependent expression. Returns the
5139 (possibly simplified) expression. */
5142 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5144 if (expr == NULL_TREE)
5147 /* If we're in a template, but EXPR isn't value dependent, simplify
5148 it. We're supposed to treat:
5150 template <typename T> void f(T[1 + 1]);
5151 template <typename T> void f(T[2]);
5153 as two declarations of the same function, for example. */
5154 if (processing_template_decl
5155 && !type_dependent_expression_p (expr)
5156 && potential_constant_expression (expr)
5157 && !value_dependent_expression_p (expr))
5159 HOST_WIDE_INT saved_processing_template_decl;
5161 saved_processing_template_decl = processing_template_decl;
5162 processing_template_decl = 0;
5163 expr = tsubst_copy_and_build (expr,
5166 /*in_decl=*/NULL_TREE,
5167 /*function_p=*/false,
5168 /*integral_constant_expression_p=*/true);
5169 processing_template_decl = saved_processing_template_decl;
5175 fold_non_dependent_expr (tree expr)
5177 return fold_non_dependent_expr_sfinae (expr, tf_error);
5180 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5181 must be a function or a pointer-to-function type, as specified
5182 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5183 and check that the resulting function has external linkage. */
5186 convert_nontype_argument_function (tree type, tree expr)
5191 fn = instantiate_type (type, fns, tf_none);
5192 if (fn == error_mark_node)
5193 return error_mark_node;
5196 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5197 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5198 if (TREE_CODE (fn_no_ptr) == BASELINK)
5199 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5201 /* [temp.arg.nontype]/1
5203 A template-argument for a non-type, non-template template-parameter
5206 -- the address of an object or function with external linkage. */
5207 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5209 error ("%qE is not a valid template argument for type %qT "
5210 "because function %qD has not external linkage",
5211 expr, type, fn_no_ptr);
5218 /* Subroutine of convert_nontype_argument.
5219 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5220 Emit an error otherwise. */
5223 check_valid_ptrmem_cst_expr (tree type, tree expr,
5224 tsubst_flags_t complain)
5227 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5229 if (complain & tf_error)
5231 error ("%qE is not a valid template argument for type %qT",
5233 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5238 /* Returns TRUE iff the address of OP is value-dependent.
5240 14.6.2.4 [temp.dep.temp]:
5241 A non-integral non-type template-argument is dependent if its type is
5242 dependent or it has either of the following forms
5245 and contains a nested-name-specifier which specifies a class-name that
5246 names a dependent type.
5248 We generalize this to just say that the address of a member of a
5249 dependent class is value-dependent; the above doesn't cover the
5250 address of a static data member named with an unqualified-id. */
5253 has_value_dependent_address (tree op)
5255 /* We could use get_inner_reference here, but there's no need;
5256 this is only relevant for template non-type arguments, which
5257 can only be expressed as &id-expression. */
5260 tree ctx = CP_DECL_CONTEXT (op);
5261 if (TYPE_P (ctx) && dependent_type_p (ctx))
5268 /* Attempt to convert the non-type template parameter EXPR to the
5269 indicated TYPE. If the conversion is successful, return the
5270 converted value. If the conversion is unsuccessful, return
5271 NULL_TREE if we issued an error message, or error_mark_node if we
5272 did not. We issue error messages for out-and-out bad template
5273 parameters, but not simply because the conversion failed, since we
5274 might be just trying to do argument deduction. Both TYPE and EXPR
5275 must be non-dependent.
5277 The conversion follows the special rules described in
5278 [temp.arg.nontype], and it is much more strict than an implicit
5281 This function is called twice for each template argument (see
5282 lookup_template_class for a more accurate description of this
5283 problem). This means that we need to handle expressions which
5284 are not valid in a C++ source, but can be created from the
5285 first call (for instance, casts to perform conversions). These
5286 hacks can go away after we fix the double coercion problem. */
5289 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5293 /* Detect immediately string literals as invalid non-type argument.
5294 This special-case is not needed for correctness (we would easily
5295 catch this later), but only to provide better diagnostic for this
5296 common user mistake. As suggested by DR 100, we do not mention
5297 linkage issues in the diagnostic as this is not the point. */
5298 /* FIXME we're making this OK. */
5299 if (TREE_CODE (expr) == STRING_CST)
5301 if (complain & tf_error)
5302 error ("%qE is not a valid template argument for type %qT "
5303 "because string literals can never be used in this context",
5308 /* Add the ADDR_EXPR now for the benefit of
5309 value_dependent_expression_p. */
5310 if (TYPE_PTROBV_P (type)
5311 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5312 expr = decay_conversion (expr);
5314 /* If we are in a template, EXPR may be non-dependent, but still
5315 have a syntactic, rather than semantic, form. For example, EXPR
5316 might be a SCOPE_REF, rather than the VAR_DECL to which the
5317 SCOPE_REF refers. Preserving the qualifying scope is necessary
5318 so that access checking can be performed when the template is
5319 instantiated -- but here we need the resolved form so that we can
5320 convert the argument. */
5321 if (TYPE_REF_OBJ_P (type)
5322 && has_value_dependent_address (expr))
5323 /* If we want the address and it's value-dependent, don't fold. */;
5324 else if (!type_unknown_p (expr))
5325 expr = fold_non_dependent_expr_sfinae (expr, complain);
5326 if (error_operand_p (expr))
5327 return error_mark_node;
5328 expr_type = TREE_TYPE (expr);
5329 if (TREE_CODE (type) == REFERENCE_TYPE)
5330 expr = mark_lvalue_use (expr);
5332 expr = mark_rvalue_use (expr);
5334 /* HACK: Due to double coercion, we can get a
5335 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5336 which is the tree that we built on the first call (see
5337 below when coercing to reference to object or to reference to
5338 function). We just strip everything and get to the arg.
5339 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5341 if (TREE_CODE (expr) == NOP_EXPR)
5343 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5345 /* ??? Maybe we could use convert_from_reference here, but we
5346 would need to relax its constraints because the NOP_EXPR
5347 could actually change the type to something more cv-qualified,
5348 and this is not folded by convert_from_reference. */
5349 tree addr = TREE_OPERAND (expr, 0);
5350 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
5351 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5352 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5353 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5354 (TREE_TYPE (expr_type),
5355 TREE_TYPE (TREE_TYPE (addr))));
5357 expr = TREE_OPERAND (addr, 0);
5358 expr_type = TREE_TYPE (expr);
5361 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5362 parameter is a pointer to object, through decay and
5363 qualification conversion. Let's strip everything. */
5364 else if (TYPE_PTROBV_P (type))
5367 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5368 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5369 /* Skip the ADDR_EXPR only if it is part of the decay for
5370 an array. Otherwise, it is part of the original argument
5371 in the source code. */
5372 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5373 expr = TREE_OPERAND (expr, 0);
5374 expr_type = TREE_TYPE (expr);
5378 /* [temp.arg.nontype]/5, bullet 1
5380 For a non-type template-parameter of integral or enumeration type,
5381 integral promotions (_conv.prom_) and integral conversions
5382 (_conv.integral_) are applied. */
5383 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5385 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5386 t = maybe_constant_value (t);
5387 if (t != error_mark_node)
5390 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5391 return error_mark_node;
5393 /* Notice that there are constant expressions like '4 % 0' which
5394 do not fold into integer constants. */
5395 if (TREE_CODE (expr) != INTEGER_CST)
5397 if (complain & tf_error)
5399 int errs = errorcount, warns = warningcount;
5400 expr = cxx_constant_value (expr);
5401 if (errorcount > errs || warningcount > warns)
5402 inform (EXPR_LOC_OR_HERE (expr),
5403 "in template argument for type %qT ", type);
5404 if (expr == error_mark_node)
5406 /* else cxx_constant_value complained but gave us
5407 a real constant, so go ahead. */
5408 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5414 /* [temp.arg.nontype]/5, bullet 2
5416 For a non-type template-parameter of type pointer to object,
5417 qualification conversions (_conv.qual_) and the array-to-pointer
5418 conversion (_conv.array_) are applied. */
5419 else if (TYPE_PTROBV_P (type))
5421 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5423 A template-argument for a non-type, non-template template-parameter
5424 shall be one of: [...]
5426 -- the name of a non-type template-parameter;
5427 -- the address of an object or function with external linkage, [...]
5428 expressed as "& id-expression" where the & is optional if the name
5429 refers to a function or array, or if the corresponding
5430 template-parameter is a reference.
5432 Here, we do not care about functions, as they are invalid anyway
5433 for a parameter of type pointer-to-object. */
5435 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5436 /* Non-type template parameters are OK. */
5438 else if (TREE_CODE (expr) != ADDR_EXPR
5439 && TREE_CODE (expr_type) != ARRAY_TYPE)
5441 if (TREE_CODE (expr) == VAR_DECL)
5443 error ("%qD is not a valid template argument "
5444 "because %qD is a variable, not the address of "
5449 /* Other values, like integer constants, might be valid
5450 non-type arguments of some other type. */
5451 return error_mark_node;
5457 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5458 ? TREE_OPERAND (expr, 0) : expr);
5459 if (TREE_CODE (decl) != VAR_DECL)
5461 error ("%qE is not a valid template argument of type %qT "
5462 "because %qE is not a variable",
5466 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5468 error ("%qE is not a valid template argument of type %qT "
5469 "because %qD does not have external linkage",
5475 expr = decay_conversion (expr);
5476 if (expr == error_mark_node)
5477 return error_mark_node;
5479 expr = perform_qualification_conversions (type, expr);
5480 if (expr == error_mark_node)
5481 return error_mark_node;
5483 /* [temp.arg.nontype]/5, bullet 3
5485 For a non-type template-parameter of type reference to object, no
5486 conversions apply. The type referred to by the reference may be more
5487 cv-qualified than the (otherwise identical) type of the
5488 template-argument. The template-parameter is bound directly to the
5489 template-argument, which must be an lvalue. */
5490 else if (TYPE_REF_OBJ_P (type))
5492 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5494 return error_mark_node;
5496 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5498 error ("%qE is not a valid template argument for type %qT "
5499 "because of conflicts in cv-qualification", expr, type);
5503 if (!real_lvalue_p (expr))
5505 error ("%qE is not a valid template argument for type %qT "
5506 "because it is not an lvalue", expr, type);
5510 /* [temp.arg.nontype]/1
5512 A template-argument for a non-type, non-template template-parameter
5513 shall be one of: [...]
5515 -- the address of an object or function with external linkage. */
5516 if (TREE_CODE (expr) == INDIRECT_REF
5517 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5519 expr = TREE_OPERAND (expr, 0);
5522 error ("%q#D is not a valid template argument for type %qT "
5523 "because a reference variable does not have a constant "
5524 "address", expr, type);
5531 error ("%qE is not a valid template argument for type %qT "
5532 "because it is not an object with external linkage",
5537 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5539 error ("%qE is not a valid template argument for type %qT "
5540 "because object %qD has not external linkage",
5545 expr = build_nop (type, build_address (expr));
5547 /* [temp.arg.nontype]/5, bullet 4
5549 For a non-type template-parameter of type pointer to function, only
5550 the function-to-pointer conversion (_conv.func_) is applied. If the
5551 template-argument represents a set of overloaded functions (or a
5552 pointer to such), the matching function is selected from the set
5554 else if (TYPE_PTRFN_P (type))
5556 /* If the argument is a template-id, we might not have enough
5557 context information to decay the pointer. */
5558 if (!type_unknown_p (expr_type))
5560 expr = decay_conversion (expr);
5561 if (expr == error_mark_node)
5562 return error_mark_node;
5565 expr = convert_nontype_argument_function (type, expr);
5566 if (!expr || expr == error_mark_node)
5569 if (TREE_CODE (expr) != ADDR_EXPR)
5571 error ("%qE is not a valid template argument for type %qT", expr, type);
5572 error ("it must be the address of a function with external linkage");
5576 /* [temp.arg.nontype]/5, bullet 5
5578 For a non-type template-parameter of type reference to function, no
5579 conversions apply. If the template-argument represents a set of
5580 overloaded functions, the matching function is selected from the set
5582 else if (TYPE_REFFN_P (type))
5584 if (TREE_CODE (expr) == ADDR_EXPR)
5586 error ("%qE is not a valid template argument for type %qT "
5587 "because it is a pointer", expr, type);
5588 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5592 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5593 if (!expr || expr == error_mark_node)
5596 expr = build_nop (type, build_address (expr));
5598 /* [temp.arg.nontype]/5, bullet 6
5600 For a non-type template-parameter of type pointer to member function,
5601 no conversions apply. If the template-argument represents a set of
5602 overloaded member functions, the matching member function is selected
5603 from the set (_over.over_). */
5604 else if (TYPE_PTRMEMFUNC_P (type))
5606 expr = instantiate_type (type, expr, tf_none);
5607 if (expr == error_mark_node)
5608 return error_mark_node;
5610 /* [temp.arg.nontype] bullet 1 says the pointer to member
5611 expression must be a pointer-to-member constant. */
5612 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5613 return error_mark_node;
5615 /* There is no way to disable standard conversions in
5616 resolve_address_of_overloaded_function (called by
5617 instantiate_type). It is possible that the call succeeded by
5618 converting &B::I to &D::I (where B is a base of D), so we need
5619 to reject this conversion here.
5621 Actually, even if there was a way to disable standard conversions,
5622 it would still be better to reject them here so that we can
5623 provide a superior diagnostic. */
5624 if (!same_type_p (TREE_TYPE (expr), type))
5626 error ("%qE is not a valid template argument for type %qT "
5627 "because it is of type %qT", expr, type,
5629 /* If we are just one standard conversion off, explain. */
5630 if (can_convert (type, TREE_TYPE (expr)))
5631 inform (input_location,
5632 "standard conversions are not allowed in this context");
5636 /* [temp.arg.nontype]/5, bullet 7
5638 For a non-type template-parameter of type pointer to data member,
5639 qualification conversions (_conv.qual_) are applied. */
5640 else if (TYPE_PTRMEM_P (type))
5642 /* [temp.arg.nontype] bullet 1 says the pointer to member
5643 expression must be a pointer-to-member constant. */
5644 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5645 return error_mark_node;
5647 expr = perform_qualification_conversions (type, expr);
5648 if (expr == error_mark_node)
5651 /* A template non-type parameter must be one of the above. */
5655 /* Sanity check: did we actually convert the argument to the
5657 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5658 (type, TREE_TYPE (expr)));
5662 /* Subroutine of coerce_template_template_parms, which returns 1 if
5663 PARM_PARM and ARG_PARM match using the rule for the template
5664 parameters of template template parameters. Both PARM and ARG are
5665 template parameters; the rest of the arguments are the same as for
5666 coerce_template_template_parms.
5669 coerce_template_template_parm (tree parm,
5671 tsubst_flags_t complain,
5675 if (arg == NULL_TREE || arg == error_mark_node
5676 || parm == NULL_TREE || parm == error_mark_node)
5679 if (TREE_CODE (arg) != TREE_CODE (parm))
5682 switch (TREE_CODE (parm))
5685 /* We encounter instantiations of templates like
5686 template <template <template <class> class> class TT>
5689 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5690 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5692 if (!coerce_template_template_parms
5693 (parmparm, argparm, complain, in_decl, outer_args))
5699 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5700 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5701 /* Argument is a parameter pack but parameter is not. */
5706 /* The tsubst call is used to handle cases such as
5708 template <int> class C {};
5709 template <class T, template <T> class TT> class D {};
5712 i.e. the parameter list of TT depends on earlier parameters. */
5713 if (!uses_template_parms (TREE_TYPE (arg))
5715 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5719 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5720 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5721 /* Argument is a parameter pack but parameter is not. */
5734 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5735 template template parameters. Both PARM_PARMS and ARG_PARMS are
5736 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5739 Consider the example:
5740 template <class T> class A;
5741 template<template <class U> class TT> class B;
5743 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5744 the parameters to A, and OUTER_ARGS contains A. */
5747 coerce_template_template_parms (tree parm_parms,
5749 tsubst_flags_t complain,
5753 int nparms, nargs, i;
5757 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5758 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5760 nparms = TREE_VEC_LENGTH (parm_parms);
5761 nargs = TREE_VEC_LENGTH (arg_parms);
5763 /* Determine whether we have a parameter pack at the end of the
5764 template template parameter's template parameter list. */
5765 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5767 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5769 if (parm == error_mark_node)
5772 switch (TREE_CODE (parm))
5776 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5781 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5791 && !(variadic_p && nargs >= nparms - 1))
5794 /* Check all of the template parameters except the parameter pack at
5795 the end (if any). */
5796 for (i = 0; i < nparms - variadic_p; ++i)
5798 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5799 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5802 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5803 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5805 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5813 /* Check each of the template parameters in the template
5814 argument against the template parameter pack at the end of
5815 the template template parameter. */
5816 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5819 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5821 for (; i < nargs; ++i)
5823 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5826 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5828 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5837 /* Verifies that the deduced template arguments (in TARGS) for the
5838 template template parameters (in TPARMS) represent valid bindings,
5839 by comparing the template parameter list of each template argument
5840 to the template parameter list of its corresponding template
5841 template parameter, in accordance with DR150. This
5842 routine can only be called after all template arguments have been
5843 deduced. It will return TRUE if all of the template template
5844 parameter bindings are okay, FALSE otherwise. */
5846 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5848 int i, ntparms = TREE_VEC_LENGTH (tparms);
5851 /* We're dealing with template parms in this process. */
5852 ++processing_template_decl;
5854 targs = INNERMOST_TEMPLATE_ARGS (targs);
5856 for (i = 0; i < ntparms; ++i)
5858 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5859 tree targ = TREE_VEC_ELT (targs, i);
5861 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5863 tree packed_args = NULL_TREE;
5866 if (ARGUMENT_PACK_P (targ))
5868 /* Look inside the argument pack. */
5869 packed_args = ARGUMENT_PACK_ARGS (targ);
5870 len = TREE_VEC_LENGTH (packed_args);
5873 for (idx = 0; idx < len; ++idx)
5875 tree targ_parms = NULL_TREE;
5878 /* Extract the next argument from the argument
5880 targ = TREE_VEC_ELT (packed_args, idx);
5882 if (PACK_EXPANSION_P (targ))
5883 /* Look at the pattern of the pack expansion. */
5884 targ = PACK_EXPANSION_PATTERN (targ);
5886 /* Extract the template parameters from the template
5888 if (TREE_CODE (targ) == TEMPLATE_DECL)
5889 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5890 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5891 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5893 /* Verify that we can coerce the template template
5894 parameters from the template argument to the template
5895 parameter. This requires an exact match. */
5897 && !coerce_template_template_parms
5898 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5913 --processing_template_decl;
5917 /* Convert the indicated template ARG as necessary to match the
5918 indicated template PARM. Returns the converted ARG, or
5919 error_mark_node if the conversion was unsuccessful. Error and
5920 warning messages are issued under control of COMPLAIN. This
5921 conversion is for the Ith parameter in the parameter list. ARGS is
5922 the full set of template arguments deduced so far. */
5925 convert_template_argument (tree parm,
5928 tsubst_flags_t complain,
5934 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5936 if (TREE_CODE (arg) == TREE_LIST
5937 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5939 /* The template argument was the name of some
5940 member function. That's usually
5941 invalid, but static members are OK. In any
5942 case, grab the underlying fields/functions
5943 and issue an error later if required. */
5944 orig_arg = TREE_VALUE (arg);
5945 TREE_TYPE (arg) = unknown_type_node;
5950 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5951 requires_type = (TREE_CODE (parm) == TYPE_DECL
5952 || requires_tmpl_type);
5954 /* When determining whether an argument pack expansion is a template,
5955 look at the pattern. */
5956 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5957 arg = PACK_EXPANSION_PATTERN (arg);
5959 /* Deal with an injected-class-name used as a template template arg. */
5960 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5962 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5963 if (TREE_CODE (t) == TEMPLATE_DECL)
5965 if (complain & tf_warning_or_error)
5966 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5967 " used as template template argument", TYPE_NAME (arg));
5968 else if (flag_pedantic_errors)
5976 ((TREE_CODE (arg) == TEMPLATE_DECL
5977 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5978 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5979 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5982 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5983 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5984 arg = TYPE_STUB_DECL (arg);
5986 is_type = TYPE_P (arg) || is_tmpl_type;
5988 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5989 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5991 permerror (input_location, "to refer to a type member of a template parameter, "
5992 "use %<typename %E%>", orig_arg);
5994 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5995 TREE_OPERAND (arg, 1),
5997 complain & tf_error);
6001 if (is_type != requires_type)
6005 if (complain & tf_error)
6007 error ("type/value mismatch at argument %d in template "
6008 "parameter list for %qD",
6011 error (" expected a constant of type %qT, got %qT",
6013 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6014 else if (requires_tmpl_type)
6015 error (" expected a class template, got %qE", orig_arg);
6017 error (" expected a type, got %qE", orig_arg);
6020 return error_mark_node;
6022 if (is_tmpl_type ^ requires_tmpl_type)
6024 if (in_decl && (complain & tf_error))
6026 error ("type/value mismatch at argument %d in template "
6027 "parameter list for %qD",
6030 error (" expected a type, got %qT", DECL_NAME (arg));
6032 error (" expected a class template, got %qT", orig_arg);
6034 return error_mark_node;
6039 if (requires_tmpl_type)
6041 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6042 /* The number of argument required is not known yet.
6043 Just accept it for now. */
6044 val = TREE_TYPE (arg);
6047 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6050 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6052 if (coerce_template_template_parms (parmparm, argparm,
6058 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6060 if (val != error_mark_node)
6062 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6063 val = TREE_TYPE (val);
6064 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6065 val = make_pack_expansion (val);
6070 if (in_decl && (complain & tf_error))
6072 error ("type/value mismatch at argument %d in "
6073 "template parameter list for %qD",
6075 error (" expected a template of type %qD, got %qT",
6079 val = error_mark_node;
6085 /* We only form one instance of each template specialization.
6086 Therefore, if we use a non-canonical variant (i.e., a
6087 typedef), any future messages referring to the type will use
6088 the typedef, which is confusing if those future uses do not
6089 themselves also use the typedef. */
6091 val = strip_typedefs (val);
6095 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6097 if (invalid_nontype_parm_type_p (t, complain))
6098 return error_mark_node;
6100 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6102 if (same_type_p (t, TREE_TYPE (orig_arg)))
6106 /* Not sure if this is reachable, but it doesn't hurt
6108 error ("type mismatch in nontype parameter pack");
6109 val = error_mark_node;
6112 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6113 /* We used to call digest_init here. However, digest_init
6114 will report errors, which we don't want when complain
6115 is zero. More importantly, digest_init will try too
6116 hard to convert things: for example, `0' should not be
6117 converted to pointer type at this point according to
6118 the standard. Accepting this is not merely an
6119 extension, since deciding whether or not these
6120 conversions can occur is part of determining which
6121 function template to call, or whether a given explicit
6122 argument specification is valid. */
6123 val = convert_nontype_argument (t, orig_arg, complain);
6127 if (val == NULL_TREE)
6128 val = error_mark_node;
6129 else if (val == error_mark_node && (complain & tf_error))
6130 error ("could not convert template argument %qE to %qT", orig_arg, t);
6132 if (TREE_CODE (val) == SCOPE_REF)
6134 /* Strip typedefs from the SCOPE_REF. */
6135 tree type = strip_typedefs (TREE_TYPE (val));
6136 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
6137 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6138 QUALIFIED_NAME_IS_TEMPLATE (val));
6145 /* Coerces the remaining template arguments in INNER_ARGS (from
6146 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6147 Returns the coerced argument pack. PARM_IDX is the position of this
6148 parameter in the template parameter list. ARGS is the original
6149 template argument list. */
6151 coerce_template_parameter_pack (tree parms,
6159 tsubst_flags_t complain)
6161 tree parm = TREE_VEC_ELT (parms, parm_idx);
6162 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6165 tree packed_types = NULL_TREE;
6167 if (arg_idx > nargs)
6170 packed_args = make_tree_vec (nargs - arg_idx);
6172 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6173 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6175 /* When the template parameter is a non-type template
6176 parameter pack whose type uses parameter packs, we need
6177 to look at each of the template arguments
6178 separately. Build a vector of the types for these
6179 non-type template parameters in PACKED_TYPES. */
6181 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6182 packed_types = tsubst_pack_expansion (expansion, args,
6185 if (packed_types == error_mark_node)
6186 return error_mark_node;
6188 /* Check that we have the right number of arguments. */
6190 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6191 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6194 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6195 error ("wrong number of template arguments (%d, should be %d)",
6196 nargs, needed_parms);
6197 return error_mark_node;
6200 /* If we aren't able to check the actual arguments now
6201 (because they haven't been expanded yet), we can at least
6202 verify that all of the types used for the non-type
6203 template parameter pack are, in fact, valid for non-type
6204 template parameters. */
6206 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6208 int j, len = TREE_VEC_LENGTH (packed_types);
6209 for (j = 0; j < len; ++j)
6211 tree t = TREE_VEC_ELT (packed_types, j);
6212 if (invalid_nontype_parm_type_p (t, complain))
6213 return error_mark_node;
6218 /* Convert the remaining arguments, which will be a part of the
6219 parameter pack "parm". */
6220 for (; arg_idx < nargs; ++arg_idx)
6222 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6223 tree actual_parm = TREE_VALUE (parm);
6225 if (packed_types && !PACK_EXPANSION_P (arg))
6227 /* When we have a vector of types (corresponding to the
6228 non-type template parameter pack that uses parameter
6229 packs in its type, as mention above), and the
6230 argument is not an expansion (which expands to a
6231 currently unknown number of arguments), clone the
6232 parm and give it the next type in PACKED_TYPES. */
6233 actual_parm = copy_node (actual_parm);
6234 TREE_TYPE (actual_parm) =
6235 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6238 if (arg != error_mark_node)
6239 arg = convert_template_argument (actual_parm,
6240 arg, new_args, complain, parm_idx,
6242 if (arg == error_mark_node)
6244 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6247 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6248 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6249 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6252 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6253 TREE_TYPE (argument_pack)
6254 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6255 TREE_CONSTANT (argument_pack) = 1;
6258 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6259 #ifdef ENABLE_CHECKING
6260 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6261 TREE_VEC_LENGTH (packed_args));
6263 return argument_pack;
6266 /* Convert all template arguments to their appropriate types, and
6267 return a vector containing the innermost resulting template
6268 arguments. If any error occurs, return error_mark_node. Error and
6269 warning messages are issued under control of COMPLAIN.
6271 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6272 for arguments not specified in ARGS. Otherwise, if
6273 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6274 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6275 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6279 coerce_template_parms (tree parms,
6282 tsubst_flags_t complain,
6283 bool require_all_args,
6284 bool use_default_args)
6286 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6289 tree new_inner_args;
6290 int saved_unevaluated_operand;
6291 int saved_inhibit_evaluation_warnings;
6293 /* When used as a boolean value, indicates whether this is a
6294 variadic template parameter list. Since it's an int, we can also
6295 subtract it from nparms to get the number of non-variadic
6299 if (args == error_mark_node)
6300 return error_mark_node;
6302 nparms = TREE_VEC_LENGTH (parms);
6304 /* Determine if there are any parameter packs. */
6305 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6307 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6308 if (template_parameter_pack_p (tparm))
6312 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6313 /* If there are 0 or 1 parameter packs, we need to expand any argument
6314 packs so that we can deduce a parameter pack from some non-packed args
6315 followed by an argument pack, as in variadic85.C. If there are more
6316 than that, we need to leave argument packs intact so the arguments are
6317 assigned to the right parameter packs. This should only happen when
6318 dealing with a nested class inside a partial specialization of a class
6319 template, as in variadic92.C. */
6320 if (variadic_p <= 1)
6321 inner_args = expand_template_argument_pack (inner_args);
6323 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6324 if ((nargs > nparms && !variadic_p)
6325 || (nargs < nparms - variadic_p
6327 && (!use_default_args
6328 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6329 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6331 if (complain & tf_error)
6336 error ("wrong number of template arguments "
6337 "(%d, should be %d or more)", nargs, nparms);
6340 error ("wrong number of template arguments "
6341 "(%d, should be %d)", nargs, nparms);
6344 error ("provided for %q+D", in_decl);
6347 return error_mark_node;
6350 /* We need to evaluate the template arguments, even though this
6351 template-id may be nested within a "sizeof". */
6352 saved_unevaluated_operand = cp_unevaluated_operand;
6353 cp_unevaluated_operand = 0;
6354 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6355 c_inhibit_evaluation_warnings = 0;
6356 new_inner_args = make_tree_vec (nparms);
6357 new_args = add_outermost_template_args (args, new_inner_args);
6358 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6363 /* Get the Ith template parameter. */
6364 parm = TREE_VEC_ELT (parms, parm_idx);
6366 if (parm == error_mark_node)
6368 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6372 /* Calculate the next argument. */
6373 if (arg_idx < nargs)
6374 arg = TREE_VEC_ELT (inner_args, arg_idx);
6378 if (template_parameter_pack_p (TREE_VALUE (parm))
6379 && !(arg && ARGUMENT_PACK_P (arg)))
6381 /* All remaining arguments will be placed in the
6382 template parameter pack PARM. */
6383 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6384 inner_args, arg_idx,
6388 /* Store this argument. */
6389 if (arg == error_mark_node)
6391 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6393 /* We are done with all of the arguments. */
6400 if (PACK_EXPANSION_P (arg))
6402 if (complain & tf_error)
6404 /* FIXME this restriction was removed by N2555; see
6406 /* If ARG is a pack expansion, but PARM is not a
6407 template parameter pack (if it were, we would have
6408 handled it above), we're trying to expand into a
6409 fixed-length argument list. */
6410 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6411 sorry ("cannot expand %<%E%> into a fixed-length "
6412 "argument list", arg);
6414 sorry ("cannot expand %<%T%> into a fixed-length "
6415 "argument list", arg);
6420 else if (require_all_args)
6422 /* There must be a default arg in this case. */
6423 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6425 /* The position of the first default template argument,
6426 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6428 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6429 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6434 if (arg == error_mark_node)
6436 if (complain & tf_error)
6437 error ("template argument %d is invalid", arg_idx + 1);
6440 /* This only occurs if there was an error in the template
6441 parameter list itself (which we would already have
6442 reported) that we are trying to recover from, e.g., a class
6443 template with a parameter list such as
6444 template<typename..., typename>. */
6447 arg = convert_template_argument (TREE_VALUE (parm),
6448 arg, new_args, complain,
6451 if (arg == error_mark_node)
6453 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6455 cp_unevaluated_operand = saved_unevaluated_operand;
6456 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6459 return error_mark_node;
6461 #ifdef ENABLE_CHECKING
6462 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6463 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6464 TREE_VEC_LENGTH (new_inner_args));
6467 return new_inner_args;
6470 /* Returns 1 if template args OT and NT are equivalent. */
6473 template_args_equal (tree ot, tree nt)
6478 if (TREE_CODE (nt) == TREE_VEC)
6479 /* For member templates */
6480 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6481 else if (PACK_EXPANSION_P (ot))
6482 return PACK_EXPANSION_P (nt)
6483 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6484 PACK_EXPANSION_PATTERN (nt));
6485 else if (ARGUMENT_PACK_P (ot))
6490 if (!ARGUMENT_PACK_P (nt))
6493 opack = ARGUMENT_PACK_ARGS (ot);
6494 npack = ARGUMENT_PACK_ARGS (nt);
6495 len = TREE_VEC_LENGTH (opack);
6496 if (TREE_VEC_LENGTH (npack) != len)
6498 for (i = 0; i < len; ++i)
6499 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6500 TREE_VEC_ELT (npack, i)))
6504 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6506 /* We get here probably because we are in the middle of substituting
6507 into the pattern of a pack expansion. In that case the
6508 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6509 interested in. So we want to use the initial pack argument for
6511 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6512 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6513 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6514 return template_args_equal (ot, nt);
6516 else if (TYPE_P (nt))
6517 return TYPE_P (ot) && same_type_p (ot, nt);
6518 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6521 return cp_tree_equal (ot, nt);
6524 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6525 of template arguments. Returns 0 otherwise. */
6528 comp_template_args (tree oldargs, tree newargs)
6532 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6535 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6537 tree nt = TREE_VEC_ELT (newargs, i);
6538 tree ot = TREE_VEC_ELT (oldargs, i);
6540 if (! template_args_equal (ot, nt))
6547 add_pending_template (tree d)
6549 tree ti = (TYPE_P (d)
6550 ? CLASSTYPE_TEMPLATE_INFO (d)
6551 : DECL_TEMPLATE_INFO (d));
6552 struct pending_template *pt;
6555 if (TI_PENDING_TEMPLATE_FLAG (ti))
6558 /* We are called both from instantiate_decl, where we've already had a
6559 tinst_level pushed, and instantiate_template, where we haven't.
6561 level = !current_tinst_level || current_tinst_level->decl != d;
6564 push_tinst_level (d);
6566 pt = ggc_alloc_pending_template ();
6568 pt->tinst = current_tinst_level;
6569 if (last_pending_template)
6570 last_pending_template->next = pt;
6572 pending_templates = pt;
6574 last_pending_template = pt;
6576 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6583 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6584 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6585 documentation for TEMPLATE_ID_EXPR. */
6588 lookup_template_function (tree fns, tree arglist)
6592 if (fns == error_mark_node || arglist == error_mark_node)
6593 return error_mark_node;
6595 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6596 gcc_assert (fns && (is_overloaded_fn (fns)
6597 || TREE_CODE (fns) == IDENTIFIER_NODE));
6599 if (BASELINK_P (fns))
6601 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6603 BASELINK_FUNCTIONS (fns),
6608 type = TREE_TYPE (fns);
6609 if (TREE_CODE (fns) == OVERLOAD || !type)
6610 type = unknown_type_node;
6612 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6615 /* Within the scope of a template class S<T>, the name S gets bound
6616 (in build_self_reference) to a TYPE_DECL for the class, not a
6617 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6618 or one of its enclosing classes, and that type is a template,
6619 return the associated TEMPLATE_DECL. Otherwise, the original
6622 Also handle the case when DECL is a TREE_LIST of ambiguous
6623 injected-class-names from different bases. */
6626 maybe_get_template_decl_from_type_decl (tree decl)
6628 if (decl == NULL_TREE)
6631 /* DR 176: A lookup that finds an injected-class-name (10.2
6632 [class.member.lookup]) can result in an ambiguity in certain cases
6633 (for example, if it is found in more than one base class). If all of
6634 the injected-class-names that are found refer to specializations of
6635 the same class template, and if the name is followed by a
6636 template-argument-list, the reference refers to the class template
6637 itself and not a specialization thereof, and is not ambiguous. */
6638 if (TREE_CODE (decl) == TREE_LIST)
6640 tree t, tmpl = NULL_TREE;
6641 for (t = decl; t; t = TREE_CHAIN (t))
6643 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6646 else if (tmpl != elt)
6649 if (tmpl && t == NULL_TREE)
6655 return (decl != NULL_TREE
6656 && DECL_SELF_REFERENCE_P (decl)
6657 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6658 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6661 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6662 parameters, find the desired type.
6664 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6666 IN_DECL, if non-NULL, is the template declaration we are trying to
6669 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6670 the class we are looking up.
6672 Issue error and warning messages under control of COMPLAIN.
6674 If the template class is really a local class in a template
6675 function, then the FUNCTION_CONTEXT is the function in which it is
6678 ??? Note that this function is currently called *twice* for each
6679 template-id: the first time from the parser, while creating the
6680 incomplete type (finish_template_type), and the second type during the
6681 real instantiation (instantiate_template_class). This is surely something
6682 that we want to avoid. It also causes some problems with argument
6683 coercion (see convert_nontype_argument for more information on this). */
6686 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
6687 int entering_scope, tsubst_flags_t complain)
6689 tree templ = NULL_TREE, parmlist;
6696 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6698 tree value = innermost_non_namespace_value (d1);
6699 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6704 push_decl_namespace (context);
6705 templ = lookup_name (d1);
6706 templ = maybe_get_template_decl_from_type_decl (templ);
6708 pop_decl_namespace ();
6711 context = DECL_CONTEXT (templ);
6713 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6715 tree type = TREE_TYPE (d1);
6717 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6718 an implicit typename for the second A. Deal with it. */
6719 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6720 type = TREE_TYPE (type);
6722 if (CLASSTYPE_TEMPLATE_INFO (type))
6724 templ = CLASSTYPE_TI_TEMPLATE (type);
6725 d1 = DECL_NAME (templ);
6728 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6729 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6731 templ = TYPE_TI_TEMPLATE (d1);
6732 d1 = DECL_NAME (templ);
6734 else if (TREE_CODE (d1) == TEMPLATE_DECL
6735 && DECL_TEMPLATE_RESULT (d1)
6736 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6739 d1 = DECL_NAME (templ);
6740 context = DECL_CONTEXT (templ);
6743 /* Issue an error message if we didn't find a template. */
6746 if (complain & tf_error)
6747 error ("%qT is not a template", d1);
6748 return error_mark_node;
6751 if (TREE_CODE (templ) != TEMPLATE_DECL
6752 /* Make sure it's a user visible template, if it was named by
6754 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6755 && !PRIMARY_TEMPLATE_P (templ)))
6757 if (complain & tf_error)
6759 error ("non-template type %qT used as a template", d1);
6761 error ("for template declaration %q+D", in_decl);
6763 return error_mark_node;
6766 complain &= ~tf_user;
6768 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6770 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6771 template arguments */
6777 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6779 /* Consider an example where a template template parameter declared as
6781 template <class T, class U = std::allocator<T> > class TT
6783 The template parameter level of T and U are one level larger than
6784 of TT. To proper process the default argument of U, say when an
6785 instantiation `TT<int>' is seen, we need to build the full
6786 arguments containing {int} as the innermost level. Outer levels,
6787 available when not appearing as default template argument, can be
6788 obtained from the arguments of the enclosing template.
6790 Suppose that TT is later substituted with std::vector. The above
6791 instantiation is `TT<int, std::allocator<T> >' with TT at
6792 level 1, and T at level 2, while the template arguments at level 1
6793 becomes {std::vector} and the inner level 2 is {int}. */
6795 outer = DECL_CONTEXT (templ);
6797 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6798 else if (current_template_parms)
6799 /* This is an argument of the current template, so we haven't set
6800 DECL_CONTEXT yet. */
6801 outer = current_template_args ();
6804 arglist = add_to_template_args (outer, arglist);
6806 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6808 /*require_all_args=*/true,
6809 /*use_default_args=*/true);
6810 if (arglist2 == error_mark_node
6811 || (!uses_template_parms (arglist2)
6812 && check_instantiated_args (templ, arglist2, complain)))
6813 return error_mark_node;
6815 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6820 tree template_type = TREE_TYPE (templ);
6823 tree found = NULL_TREE;
6826 int is_dependent_type;
6827 int use_partial_inst_tmpl = false;
6829 gen_tmpl = most_general_template (templ);
6830 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6831 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6832 arg_depth = TMPL_ARGS_DEPTH (arglist);
6834 if (arg_depth == 1 && parm_depth > 1)
6836 /* We've been given an incomplete set of template arguments.
6839 template <class T> struct S1 {
6840 template <class U> struct S2 {};
6841 template <class U> struct S2<U*> {};
6844 we will be called with an ARGLIST of `U*', but the
6845 TEMPLATE will be `template <class T> template
6846 <class U> struct S1<T>::S2'. We must fill in the missing
6849 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6851 arg_depth = TMPL_ARGS_DEPTH (arglist);
6854 /* Now we should have enough arguments. */
6855 gcc_assert (parm_depth == arg_depth);
6857 /* From here on, we're only interested in the most general
6860 /* Calculate the BOUND_ARGS. These will be the args that are
6861 actually tsubst'd into the definition to create the
6865 /* We have multiple levels of arguments to coerce, at once. */
6867 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6869 tree bound_args = make_tree_vec (parm_depth);
6871 for (i = saved_depth,
6872 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6873 i > 0 && t != NULL_TREE;
6874 --i, t = TREE_CHAIN (t))
6877 if (i == saved_depth)
6878 a = coerce_template_parms (TREE_VALUE (t),
6881 /*require_all_args=*/true,
6882 /*use_default_args=*/true);
6884 /* Outer levels should have already been coerced. */
6885 a = TMPL_ARGS_LEVEL (arglist, i);
6887 /* Don't process further if one of the levels fails. */
6888 if (a == error_mark_node)
6890 /* Restore the ARGLIST to its full size. */
6891 TREE_VEC_LENGTH (arglist) = saved_depth;
6892 return error_mark_node;
6895 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6897 /* We temporarily reduce the length of the ARGLIST so
6898 that coerce_template_parms will see only the arguments
6899 corresponding to the template parameters it is
6901 TREE_VEC_LENGTH (arglist)--;
6904 /* Restore the ARGLIST to its full size. */
6905 TREE_VEC_LENGTH (arglist) = saved_depth;
6907 arglist = bound_args;
6911 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6912 INNERMOST_TEMPLATE_ARGS (arglist),
6915 /*require_all_args=*/true,
6916 /*use_default_args=*/true);
6918 if (arglist == error_mark_node)
6919 /* We were unable to bind the arguments. */
6920 return error_mark_node;
6922 /* In the scope of a template class, explicit references to the
6923 template class refer to the type of the template, not any
6924 instantiation of it. For example, in:
6926 template <class T> class C { void f(C<T>); }
6928 the `C<T>' is just the same as `C'. Outside of the
6929 class, however, such a reference is an instantiation. */
6931 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6932 || currently_open_class (template_type))
6933 /* comp_template_args is expensive, check it last. */
6934 && comp_template_args (TYPE_TI_ARGS (template_type),
6936 return template_type;
6938 /* If we already have this specialization, return it. */
6939 elt.tmpl = gen_tmpl;
6941 hash = hash_specialization (&elt);
6942 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6948 is_dependent_type = uses_template_parms (arglist);
6950 /* If the deduced arguments are invalid, then the binding
6952 if (!is_dependent_type
6953 && check_instantiated_args (gen_tmpl,
6954 INNERMOST_TEMPLATE_ARGS (arglist),
6956 return error_mark_node;
6958 if (!is_dependent_type
6959 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6960 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6961 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6963 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6964 DECL_NAME (gen_tmpl),
6965 /*tag_scope=*/ts_global);
6969 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6972 context = global_namespace;
6974 /* Create the type. */
6975 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6977 if (!is_dependent_type)
6979 set_current_access_from_decl (TYPE_NAME (template_type));
6980 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
6981 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6982 arglist, complain, in_decl),
6983 SCOPED_ENUM_P (template_type), NULL);
6987 /* We don't want to call start_enum for this type, since
6988 the values for the enumeration constants may involve
6989 template parameters. And, no one should be interested
6990 in the enumeration constants for such a type. */
6991 t = cxx_make_type (ENUMERAL_TYPE);
6992 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6994 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
6995 ENUM_FIXED_UNDERLYING_TYPE_P (t)
6996 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7000 t = make_class_type (TREE_CODE (template_type));
7001 CLASSTYPE_DECLARED_CLASS (t)
7002 = CLASSTYPE_DECLARED_CLASS (template_type);
7003 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7004 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7006 /* A local class. Make sure the decl gets registered properly. */
7007 if (context == current_function_decl)
7008 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7010 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7011 /* This instantiation is another name for the primary
7012 template type. Set the TYPE_CANONICAL field
7014 TYPE_CANONICAL (t) = template_type;
7015 else if (any_template_arguments_need_structural_equality_p (arglist))
7016 /* Some of the template arguments require structural
7017 equality testing, so this template class requires
7018 structural equality testing. */
7019 SET_TYPE_STRUCTURAL_EQUALITY (t);
7022 /* If we called start_enum or pushtag above, this information
7023 will already be set up. */
7026 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7028 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7029 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7030 DECL_SOURCE_LOCATION (type_decl)
7031 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7034 type_decl = TYPE_NAME (t);
7036 TREE_PRIVATE (type_decl)
7037 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7038 TREE_PROTECTED (type_decl)
7039 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7040 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7042 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7043 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7046 /* Let's consider the explicit specialization of a member
7047 of a class template specialization that is implicitely instantiated,
7052 template<class U> struct M {}; //#0
7057 struct S<int>::M<char> //#1
7061 [temp.expl.spec]/4 says this is valid.
7063 In this case, when we write:
7066 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7069 When we encounter #1, we want to store the partial instantiation
7070 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7072 For all cases other than this "explicit specialization of member of a
7073 class template", we just want to store the most general template into
7074 the CLASSTYPE_TI_TEMPLATE of M.
7076 This case of "explicit specialization of member of a class template"
7078 1/ the enclosing class is an instantiation of, and therefore not
7079 the same as, the context of the most general template, and
7080 2/ we aren't looking at the partial instantiation itself, i.e.
7081 the innermost arguments are not the same as the innermost parms of
7082 the most general template.
7084 So it's only when 1/ and 2/ happens that we want to use the partial
7085 instantiation of the member template in lieu of its most general
7088 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7089 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7090 /* the enclosing class must be an instantiation... */
7091 && CLASS_TYPE_P (context)
7092 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7094 tree partial_inst_args;
7095 TREE_VEC_LENGTH (arglist)--;
7096 ++processing_template_decl;
7098 tsubst (INNERMOST_TEMPLATE_ARGS
7099 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7100 arglist, complain, NULL_TREE);
7101 --processing_template_decl;
7102 TREE_VEC_LENGTH (arglist)++;
7103 use_partial_inst_tmpl =
7104 /*...and we must not be looking at the partial instantiation
7106 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7110 if (!use_partial_inst_tmpl)
7111 /* This case is easy; there are no member templates involved. */
7115 /* This is a full instantiation of a member template. Find
7116 the partial instantiation of which this is an instance. */
7118 /* Temporarily reduce by one the number of levels in the ARGLIST
7119 so as to avoid comparing the last set of arguments. */
7120 TREE_VEC_LENGTH (arglist)--;
7121 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7122 TREE_VEC_LENGTH (arglist)++;
7123 found = CLASSTYPE_TI_TEMPLATE (found);
7126 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7129 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
7130 &elt, hash, INSERT);
7131 *slot = ggc_alloc_spec_entry ();
7134 /* Note this use of the partial instantiation so we can check it
7135 later in maybe_process_partial_specialization. */
7136 DECL_TEMPLATE_INSTANTIATIONS (templ)
7137 = tree_cons (arglist, t,
7138 DECL_TEMPLATE_INSTANTIATIONS (templ));
7140 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7141 /* Now that the type has been registered on the instantiations
7142 list, we set up the enumerators. Because the enumeration
7143 constants may involve the enumeration type itself, we make
7144 sure to register the type first, and then create the
7145 constants. That way, doing tsubst_expr for the enumeration
7146 constants won't result in recursive calls here; we'll find
7147 the instantiation and exit above. */
7148 tsubst_enum (template_type, t, arglist);
7150 if (is_dependent_type)
7151 /* If the type makes use of template parameters, the
7152 code that generates debugging information will crash. */
7153 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7155 /* Possibly limit visibility based on template args. */
7156 TREE_PUBLIC (type_decl) = 1;
7157 determine_visibility (type_decl);
7163 /* Wrapper for lookup_template_class_1. */
7166 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7167 int entering_scope, tsubst_flags_t complain)
7170 timevar_push (TV_TEMPLATE_INST);
7171 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7172 entering_scope, complain);
7173 timevar_pop (TV_TEMPLATE_INST);
7181 /* True when we should also visit template parameters that occur in
7182 non-deduced contexts. */
7183 bool include_nondeduced_p;
7184 struct pointer_set_t *visited;
7187 /* Called from for_each_template_parm via walk_tree. */
7190 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7193 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7194 tree_fn_t fn = pfd->fn;
7195 void *data = pfd->data;
7198 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7199 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7200 pfd->include_nondeduced_p))
7201 return error_mark_node;
7203 switch (TREE_CODE (t))
7206 if (TYPE_PTRMEMFUNC_P (t))
7212 if (!TYPE_TEMPLATE_INFO (t))
7214 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7215 fn, data, pfd->visited,
7216 pfd->include_nondeduced_p))
7217 return error_mark_node;
7221 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7222 fn, data, pfd->visited,
7223 pfd->include_nondeduced_p)
7224 || for_each_template_parm (TYPE_MAX_VALUE (t),
7225 fn, data, pfd->visited,
7226 pfd->include_nondeduced_p))
7227 return error_mark_node;
7231 /* Since we're not going to walk subtrees, we have to do this
7233 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7234 pfd->visited, pfd->include_nondeduced_p))
7235 return error_mark_node;
7239 /* Check the return type. */
7240 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7241 pfd->include_nondeduced_p))
7242 return error_mark_node;
7244 /* Check the parameter types. Since default arguments are not
7245 instantiated until they are needed, the TYPE_ARG_TYPES may
7246 contain expressions that involve template parameters. But,
7247 no-one should be looking at them yet. And, once they're
7248 instantiated, they don't contain template parameters, so
7249 there's no point in looking at them then, either. */
7253 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7254 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7255 pfd->visited, pfd->include_nondeduced_p))
7256 return error_mark_node;
7258 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7259 want walk_tree walking into them itself. */
7265 case UNDERLYING_TYPE:
7266 if (pfd->include_nondeduced_p
7267 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7269 pfd->include_nondeduced_p))
7270 return error_mark_node;
7275 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7276 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7277 pfd->visited, pfd->include_nondeduced_p))
7278 return error_mark_node;
7283 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7284 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7285 pfd->visited, pfd->include_nondeduced_p))
7286 return error_mark_node;
7287 if (DECL_CONTEXT (t)
7288 && pfd->include_nondeduced_p
7289 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7290 pfd->visited, pfd->include_nondeduced_p))
7291 return error_mark_node;
7294 case BOUND_TEMPLATE_TEMPLATE_PARM:
7295 /* Record template parameters such as `T' inside `TT<T>'. */
7296 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7297 pfd->include_nondeduced_p))
7298 return error_mark_node;
7301 case TEMPLATE_TEMPLATE_PARM:
7302 case TEMPLATE_TYPE_PARM:
7303 case TEMPLATE_PARM_INDEX:
7304 if (fn && (*fn)(t, data))
7305 return error_mark_node;
7307 return error_mark_node;
7311 /* A template template parameter is encountered. */
7312 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7313 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7314 pfd->include_nondeduced_p))
7315 return error_mark_node;
7317 /* Already substituted template template parameter */
7323 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7325 pfd->include_nondeduced_p))
7326 return error_mark_node;
7330 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7331 && pfd->include_nondeduced_p
7332 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7333 (TREE_TYPE (t)), fn, data,
7334 pfd->visited, pfd->include_nondeduced_p))
7335 return error_mark_node;
7340 /* If there's no type, then this thing must be some expression
7341 involving template parameters. */
7342 if (!fn && !TREE_TYPE (t))
7343 return error_mark_node;
7348 case REINTERPRET_CAST_EXPR:
7349 case CONST_CAST_EXPR:
7350 case STATIC_CAST_EXPR:
7351 case DYNAMIC_CAST_EXPR:
7355 case PSEUDO_DTOR_EXPR:
7357 return error_mark_node;
7364 /* We didn't find any template parameters we liked. */
7368 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7369 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7370 call FN with the parameter and the DATA.
7371 If FN returns nonzero, the iteration is terminated, and
7372 for_each_template_parm returns 1. Otherwise, the iteration
7373 continues. If FN never returns a nonzero value, the value
7374 returned by for_each_template_parm is 0. If FN is NULL, it is
7375 considered to be the function which always returns 1.
7377 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7378 parameters that occur in non-deduced contexts. When false, only
7379 visits those template parameters that can be deduced. */
7382 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7383 struct pointer_set_t *visited,
7384 bool include_nondeduced_p)
7386 struct pair_fn_data pfd;
7392 pfd.include_nondeduced_p = include_nondeduced_p;
7394 /* Walk the tree. (Conceptually, we would like to walk without
7395 duplicates, but for_each_template_parm_r recursively calls
7396 for_each_template_parm, so we would need to reorganize a fair
7397 bit to use walk_tree_without_duplicates, so we keep our own
7400 pfd.visited = visited;
7402 pfd.visited = pointer_set_create ();
7403 result = cp_walk_tree (&t,
7404 for_each_template_parm_r,
7406 pfd.visited) != NULL_TREE;
7411 pointer_set_destroy (pfd.visited);
7418 /* Returns true if T depends on any template parameter. */
7421 uses_template_parms (tree t)
7424 int saved_processing_template_decl;
7426 saved_processing_template_decl = processing_template_decl;
7427 if (!saved_processing_template_decl)
7428 processing_template_decl = 1;
7430 dependent_p = dependent_type_p (t);
7431 else if (TREE_CODE (t) == TREE_VEC)
7432 dependent_p = any_dependent_template_arguments_p (t);
7433 else if (TREE_CODE (t) == TREE_LIST)
7434 dependent_p = (uses_template_parms (TREE_VALUE (t))
7435 || uses_template_parms (TREE_CHAIN (t)));
7436 else if (TREE_CODE (t) == TYPE_DECL)
7437 dependent_p = dependent_type_p (TREE_TYPE (t));
7440 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7441 || TREE_CODE (t) == OVERLOAD
7442 || TREE_CODE (t) == BASELINK
7443 || TREE_CODE (t) == IDENTIFIER_NODE
7444 || TREE_CODE (t) == TRAIT_EXPR
7445 || TREE_CODE (t) == CONSTRUCTOR
7446 || CONSTANT_CLASS_P (t))
7447 dependent_p = (type_dependent_expression_p (t)
7448 || value_dependent_expression_p (t));
7451 gcc_assert (t == error_mark_node);
7452 dependent_p = false;
7455 processing_template_decl = saved_processing_template_decl;
7460 /* Returns true if T depends on any template parameter with level LEVEL. */
7463 uses_template_parms_level (tree t, int level)
7465 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7466 /*include_nondeduced_p=*/true);
7469 static int tinst_depth;
7470 extern int max_tinst_depth;
7471 #ifdef GATHER_STATISTICS
7474 static int tinst_level_tick;
7475 static int last_template_error_tick;
7477 /* We're starting to instantiate D; record the template instantiation context
7478 for diagnostics and to restore it later. */
7481 push_tinst_level (tree d)
7483 struct tinst_level *new_level;
7485 if (tinst_depth >= max_tinst_depth)
7487 /* If the instantiation in question still has unbound template parms,
7488 we don't really care if we can't instantiate it, so just return.
7489 This happens with base instantiation for implicit `typename'. */
7490 if (uses_template_parms (d))
7493 last_template_error_tick = tinst_level_tick;
7494 error ("template instantiation depth exceeds maximum of %d (use "
7495 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7496 max_tinst_depth, d);
7498 print_instantiation_context ();
7503 new_level = ggc_alloc_tinst_level ();
7504 new_level->decl = d;
7505 new_level->locus = input_location;
7506 new_level->in_system_header_p = in_system_header;
7507 new_level->next = current_tinst_level;
7508 current_tinst_level = new_level;
7511 #ifdef GATHER_STATISTICS
7512 if (tinst_depth > depth_reached)
7513 depth_reached = tinst_depth;
7520 /* We're done instantiating this template; return to the instantiation
7524 pop_tinst_level (void)
7526 /* Restore the filename and line number stashed away when we started
7527 this instantiation. */
7528 input_location = current_tinst_level->locus;
7529 current_tinst_level = current_tinst_level->next;
7534 /* We're instantiating a deferred template; restore the template
7535 instantiation context in which the instantiation was requested, which
7536 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7539 reopen_tinst_level (struct tinst_level *level)
7541 struct tinst_level *t;
7544 for (t = level; t; t = t->next)
7547 current_tinst_level = level;
7552 /* Returns the TINST_LEVEL which gives the original instantiation
7555 struct tinst_level *
7556 outermost_tinst_level (void)
7558 struct tinst_level *level = current_tinst_level;
7561 level = level->next;
7565 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7568 parameter_of_template_p (tree parm, tree templ)
7573 if (!parm || !templ)
7576 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7577 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7579 parms = DECL_TEMPLATE_PARMS (templ);
7580 parms = INNERMOST_TEMPLATE_PARMS (parms);
7582 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7583 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7589 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7590 vector of template arguments, as for tsubst.
7592 Returns an appropriate tsubst'd friend declaration. */
7595 tsubst_friend_function (tree decl, tree args)
7599 if (TREE_CODE (decl) == FUNCTION_DECL
7600 && DECL_TEMPLATE_INSTANTIATION (decl)
7601 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7602 /* This was a friend declared with an explicit template
7603 argument list, e.g.:
7607 to indicate that f was a template instantiation, not a new
7608 function declaration. Now, we have to figure out what
7609 instantiation of what template. */
7611 tree template_id, arglist, fns;
7614 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7616 /* Friend functions are looked up in the containing namespace scope.
7617 We must enter that scope, to avoid finding member functions of the
7618 current class with same name. */
7619 push_nested_namespace (ns);
7620 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7621 tf_warning_or_error, NULL_TREE,
7622 /*integral_constant_expression_p=*/false);
7623 pop_nested_namespace (ns);
7624 arglist = tsubst (DECL_TI_ARGS (decl), args,
7625 tf_warning_or_error, NULL_TREE);
7626 template_id = lookup_template_function (fns, arglist);
7628 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7629 tmpl = determine_specialization (template_id, new_friend,
7631 /*need_member_template=*/0,
7632 TREE_VEC_LENGTH (args),
7634 return instantiate_template (tmpl, new_args, tf_error);
7637 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7639 /* The NEW_FRIEND will look like an instantiation, to the
7640 compiler, but is not an instantiation from the point of view of
7641 the language. For example, we might have had:
7643 template <class T> struct S {
7644 template <class U> friend void f(T, U);
7647 Then, in S<int>, template <class U> void f(int, U) is not an
7648 instantiation of anything. */
7649 if (new_friend == error_mark_node)
7650 return error_mark_node;
7652 DECL_USE_TEMPLATE (new_friend) = 0;
7653 if (TREE_CODE (decl) == TEMPLATE_DECL)
7655 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7656 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7657 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7660 /* The mangled name for the NEW_FRIEND is incorrect. The function
7661 is not a template instantiation and should not be mangled like
7662 one. Therefore, we forget the mangling here; we'll recompute it
7663 later if we need it. */
7664 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7666 SET_DECL_RTL (new_friend, NULL);
7667 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7670 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7673 tree new_friend_template_info;
7674 tree new_friend_result_template_info;
7676 int new_friend_is_defn;
7678 /* We must save some information from NEW_FRIEND before calling
7679 duplicate decls since that function will free NEW_FRIEND if
7681 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7682 new_friend_is_defn =
7683 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7684 (template_for_substitution (new_friend)))
7686 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7688 /* This declaration is a `primary' template. */
7689 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7691 new_friend_result_template_info
7692 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7695 new_friend_result_template_info = NULL_TREE;
7697 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7698 if (new_friend_is_defn)
7699 DECL_INITIAL (new_friend) = error_mark_node;
7701 /* Inside pushdecl_namespace_level, we will push into the
7702 current namespace. However, the friend function should go
7703 into the namespace of the template. */
7704 ns = decl_namespace_context (new_friend);
7705 push_nested_namespace (ns);
7706 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7707 pop_nested_namespace (ns);
7709 if (old_decl == error_mark_node)
7710 return error_mark_node;
7712 if (old_decl != new_friend)
7714 /* This new friend declaration matched an existing
7715 declaration. For example, given:
7717 template <class T> void f(T);
7718 template <class U> class C {
7719 template <class T> friend void f(T) {}
7722 the friend declaration actually provides the definition
7723 of `f', once C has been instantiated for some type. So,
7724 old_decl will be the out-of-class template declaration,
7725 while new_friend is the in-class definition.
7727 But, if `f' was called before this point, the
7728 instantiation of `f' will have DECL_TI_ARGS corresponding
7729 to `T' but not to `U', references to which might appear
7730 in the definition of `f'. Previously, the most general
7731 template for an instantiation of `f' was the out-of-class
7732 version; now it is the in-class version. Therefore, we
7733 run through all specialization of `f', adding to their
7734 DECL_TI_ARGS appropriately. In particular, they need a
7735 new set of outer arguments, corresponding to the
7736 arguments for this class instantiation.
7738 The same situation can arise with something like this:
7741 template <class T> class C {
7745 when `C<int>' is instantiated. Now, `f(int)' is defined
7748 if (!new_friend_is_defn)
7749 /* On the other hand, if the in-class declaration does
7750 *not* provide a definition, then we don't want to alter
7751 existing definitions. We can just leave everything
7756 tree new_template = TI_TEMPLATE (new_friend_template_info);
7757 tree new_args = TI_ARGS (new_friend_template_info);
7759 /* Overwrite whatever template info was there before, if
7760 any, with the new template information pertaining to
7762 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7764 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7766 /* We should have called reregister_specialization in
7768 gcc_assert (retrieve_specialization (new_template,
7772 /* Instantiate it if the global has already been used. */
7773 if (DECL_ODR_USED (old_decl))
7774 instantiate_decl (old_decl, /*defer_ok=*/true,
7775 /*expl_inst_class_mem_p=*/false);
7781 /* Indicate that the old function template is a partial
7783 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7784 = new_friend_result_template_info;
7786 gcc_assert (new_template
7787 == most_general_template (new_template));
7788 gcc_assert (new_template != old_decl);
7790 /* Reassign any specializations already in the hash table
7791 to the new more general template, and add the
7792 additional template args. */
7793 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7797 tree spec = TREE_VALUE (t);
7800 elt.tmpl = old_decl;
7801 elt.args = DECL_TI_ARGS (spec);
7802 elt.spec = NULL_TREE;
7804 htab_remove_elt (decl_specializations, &elt);
7807 = add_outermost_template_args (new_args,
7808 DECL_TI_ARGS (spec));
7810 register_specialization
7811 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7814 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7818 /* The information from NEW_FRIEND has been merged into OLD_DECL
7819 by duplicate_decls. */
7820 new_friend = old_decl;
7825 tree context = DECL_CONTEXT (new_friend);
7829 template <class T> class C {
7830 template <class U> friend void C1<U>::f (); // case 1
7831 friend void C2<T>::f (); // case 2
7833 we only need to make sure CONTEXT is a complete type for
7834 case 2. To distinguish between the two cases, we note that
7835 CONTEXT of case 1 remains dependent type after tsubst while
7836 this isn't true for case 2. */
7837 ++processing_template_decl;
7838 dependent_p = dependent_type_p (context);
7839 --processing_template_decl;
7842 && !complete_type_or_else (context, NULL_TREE))
7843 return error_mark_node;
7845 if (COMPLETE_TYPE_P (context))
7847 /* Check to see that the declaration is really present, and,
7848 possibly obtain an improved declaration. */
7849 tree fn = check_classfn (context,
7850 new_friend, NULL_TREE);
7860 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7861 template arguments, as for tsubst.
7863 Returns an appropriate tsubst'd friend type or error_mark_node on
7867 tsubst_friend_class (tree friend_tmpl, tree args)
7873 context = CP_DECL_CONTEXT (friend_tmpl);
7875 if (context != global_namespace)
7877 if (TREE_CODE (context) == NAMESPACE_DECL)
7878 push_nested_namespace (context);
7880 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7883 /* Look for a class template declaration. We look for hidden names
7884 because two friend declarations of the same template are the
7885 same. For example, in:
7888 template <typename> friend class F;
7890 template <typename> struct B {
7891 template <typename> friend class F;
7894 both F templates are the same. */
7895 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7896 /*block_p=*/true, 0,
7897 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7899 /* But, if we don't find one, it might be because we're in a
7900 situation like this:
7908 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7909 for `S<int>', not the TEMPLATE_DECL. */
7910 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7912 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7913 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7916 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7918 /* The friend template has already been declared. Just
7919 check to see that the declarations match, and install any new
7920 default parameters. We must tsubst the default parameters,
7921 of course. We only need the innermost template parameters
7922 because that is all that redeclare_class_template will look
7924 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7925 > TMPL_ARGS_DEPTH (args))
7928 location_t saved_input_location;
7929 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7930 args, tf_warning_or_error);
7932 saved_input_location = input_location;
7933 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7934 redeclare_class_template (TREE_TYPE (tmpl), parms);
7935 input_location = saved_input_location;
7939 friend_type = TREE_TYPE (tmpl);
7943 /* The friend template has not already been declared. In this
7944 case, the instantiation of the template class will cause the
7945 injection of this template into the global scope. */
7946 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7947 if (tmpl == error_mark_node)
7948 return error_mark_node;
7950 /* The new TMPL is not an instantiation of anything, so we
7951 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7952 the new type because that is supposed to be the corresponding
7953 template decl, i.e., TMPL. */
7954 DECL_USE_TEMPLATE (tmpl) = 0;
7955 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7956 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7957 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7958 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7960 /* Inject this template into the global scope. */
7961 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7964 if (context != global_namespace)
7966 if (TREE_CODE (context) == NAMESPACE_DECL)
7967 pop_nested_namespace (context);
7969 pop_nested_class ();
7975 /* Returns zero if TYPE cannot be completed later due to circularity.
7976 Otherwise returns one. */
7979 can_complete_type_without_circularity (tree type)
7981 if (type == NULL_TREE || type == error_mark_node)
7983 else if (COMPLETE_TYPE_P (type))
7985 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7986 return can_complete_type_without_circularity (TREE_TYPE (type));
7987 else if (CLASS_TYPE_P (type)
7988 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7994 /* Apply any attributes which had to be deferred until instantiation
7995 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7996 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7999 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8000 tree args, tsubst_flags_t complain, tree in_decl)
8002 tree last_dep = NULL_TREE;
8006 for (t = attributes; t; t = TREE_CHAIN (t))
8007 if (ATTR_IS_DEPENDENT (t))
8010 attributes = copy_list (attributes);
8014 if (DECL_P (*decl_p))
8016 if (TREE_TYPE (*decl_p) == error_mark_node)
8018 p = &DECL_ATTRIBUTES (*decl_p);
8021 p = &TYPE_ATTRIBUTES (*decl_p);
8025 tree late_attrs = NULL_TREE;
8026 tree *q = &late_attrs;
8028 for (*p = attributes; *p; )
8031 if (ATTR_IS_DEPENDENT (t))
8033 *p = TREE_CHAIN (t);
8034 TREE_CHAIN (t) = NULL_TREE;
8035 /* If the first attribute argument is an identifier, don't
8036 pass it through tsubst. Attributes like mode, format,
8037 cleanup and several target specific attributes expect it
8040 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8041 && TREE_VALUE (TREE_VALUE (t))
8042 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8043 == IDENTIFIER_NODE))
8046 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8048 /*integral_constant_expression_p=*/false);
8049 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8051 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8056 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8057 /*integral_constant_expression_p=*/false);
8059 q = &TREE_CHAIN (t);
8062 p = &TREE_CHAIN (t);
8065 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8069 /* Perform (or defer) access check for typedefs that were referenced
8070 from within the template TMPL code.
8071 This is a subroutine of instantiate_template and instantiate_class_template.
8072 TMPL is the template to consider and TARGS is the list of arguments of
8076 perform_typedefs_access_check (tree tmpl, tree targs)
8078 location_t saved_location;
8080 qualified_typedef_usage_t *iter;
8083 || (!CLASS_TYPE_P (tmpl)
8084 && TREE_CODE (tmpl) != FUNCTION_DECL))
8087 saved_location = input_location;
8088 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8089 get_types_needing_access_check (tmpl),
8092 tree type_decl = iter->typedef_decl;
8093 tree type_scope = iter->context;
8095 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8098 if (uses_template_parms (type_decl))
8099 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8100 if (uses_template_parms (type_scope))
8101 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8103 /* Make access check error messages point to the location
8104 of the use of the typedef. */
8105 input_location = iter->locus;
8106 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8107 type_decl, type_decl);
8109 input_location = saved_location;
8113 instantiate_class_template_1 (tree type)
8115 tree templ, args, pattern, t, member;
8119 unsigned int saved_maximum_field_alignment;
8121 if (type == error_mark_node)
8122 return error_mark_node;
8124 if (COMPLETE_OR_OPEN_TYPE_P (type)
8125 || uses_template_parms (type))
8128 /* Figure out which template is being instantiated. */
8129 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8130 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8132 /* Determine what specialization of the original template to
8134 t = most_specialized_class (type, templ, tf_warning_or_error);
8135 if (t == error_mark_node)
8137 TYPE_BEING_DEFINED (type) = 1;
8138 return error_mark_node;
8142 /* This TYPE is actually an instantiation of a partial
8143 specialization. We replace the innermost set of ARGS with
8144 the arguments appropriate for substitution. For example,
8147 template <class T> struct S {};
8148 template <class T> struct S<T*> {};
8150 and supposing that we are instantiating S<int*>, ARGS will
8151 presently be {int*} -- but we need {int}. */
8152 pattern = TREE_TYPE (t);
8153 args = TREE_PURPOSE (t);
8157 pattern = TREE_TYPE (templ);
8158 args = CLASSTYPE_TI_ARGS (type);
8161 /* If the template we're instantiating is incomplete, then clearly
8162 there's nothing we can do. */
8163 if (!COMPLETE_TYPE_P (pattern))
8166 /* If we've recursively instantiated too many templates, stop. */
8167 if (! push_tinst_level (type))
8170 /* Now we're really doing the instantiation. Mark the type as in
8171 the process of being defined. */
8172 TYPE_BEING_DEFINED (type) = 1;
8174 /* We may be in the middle of deferred access check. Disable
8176 push_deferring_access_checks (dk_no_deferred);
8178 push_to_top_level ();
8179 /* Use #pragma pack from the template context. */
8180 saved_maximum_field_alignment = maximum_field_alignment;
8181 maximum_field_alignment = TYPE_PRECISION (pattern);
8183 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8185 /* Set the input location to the most specialized template definition.
8186 This is needed if tsubsting causes an error. */
8187 typedecl = TYPE_MAIN_DECL (pattern);
8188 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8189 DECL_SOURCE_LOCATION (typedecl);
8191 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
8192 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
8193 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
8194 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
8195 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
8196 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
8197 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
8198 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
8199 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
8200 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
8201 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8202 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8203 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8204 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8205 if (ANON_AGGR_TYPE_P (pattern))
8206 SET_ANON_AGGR_TYPE_P (type);
8207 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8209 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8210 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8212 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8214 pbinfo = TYPE_BINFO (pattern);
8216 /* We should never instantiate a nested class before its enclosing
8217 class; we need to look up the nested class by name before we can
8218 instantiate it, and that lookup should instantiate the enclosing
8220 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8221 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8223 base_list = NULL_TREE;
8224 if (BINFO_N_BASE_BINFOS (pbinfo))
8230 /* We must enter the scope containing the type, as that is where
8231 the accessibility of types named in dependent bases are
8233 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8235 /* Substitute into each of the bases to determine the actual
8237 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8240 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8241 tree expanded_bases = NULL_TREE;
8244 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8247 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8248 args, tf_error, NULL_TREE);
8249 if (expanded_bases == error_mark_node)
8252 len = TREE_VEC_LENGTH (expanded_bases);
8255 for (idx = 0; idx < len; idx++)
8258 /* Extract the already-expanded base class. */
8259 base = TREE_VEC_ELT (expanded_bases, idx);
8261 /* Substitute to figure out the base class. */
8262 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8265 if (base == error_mark_node)
8268 base_list = tree_cons (access, base, base_list);
8269 if (BINFO_VIRTUAL_P (pbase_binfo))
8270 TREE_TYPE (base_list) = integer_type_node;
8274 /* The list is now in reverse order; correct that. */
8275 base_list = nreverse (base_list);
8278 pop_scope (pushed_scope);
8280 /* Now call xref_basetypes to set up all the base-class
8282 xref_basetypes (type, base_list);
8284 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8285 (int) ATTR_FLAG_TYPE_IN_PLACE,
8286 args, tf_error, NULL_TREE);
8287 fixup_attribute_variants (type);
8289 /* Now that our base classes are set up, enter the scope of the
8290 class, so that name lookups into base classes, etc. will work
8291 correctly. This is precisely analogous to what we do in
8292 begin_class_definition when defining an ordinary non-template
8293 class, except we also need to push the enclosing classes. */
8294 push_nested_class (type);
8296 /* Now members are processed in the order of declaration. */
8297 for (member = CLASSTYPE_DECL_LIST (pattern);
8298 member; member = TREE_CHAIN (member))
8300 tree t = TREE_VALUE (member);
8302 if (TREE_PURPOSE (member))
8306 /* Build new CLASSTYPE_NESTED_UTDS. */
8309 bool class_template_p;
8311 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8312 && TYPE_LANG_SPECIFIC (t)
8313 && CLASSTYPE_IS_TEMPLATE (t));
8314 /* If the member is a class template, then -- even after
8315 substitution -- there may be dependent types in the
8316 template argument list for the class. We increment
8317 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8318 that function will assume that no types are dependent
8319 when outside of a template. */
8320 if (class_template_p)
8321 ++processing_template_decl;
8322 newtag = tsubst (t, args, tf_error, NULL_TREE);
8323 if (class_template_p)
8324 --processing_template_decl;
8325 if (newtag == error_mark_node)
8328 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8330 tree name = TYPE_IDENTIFIER (t);
8332 if (class_template_p)
8333 /* Unfortunately, lookup_template_class sets
8334 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8335 instantiation (i.e., for the type of a member
8336 template class nested within a template class.)
8337 This behavior is required for
8338 maybe_process_partial_specialization to work
8339 correctly, but is not accurate in this case;
8340 the TAG is not an instantiation of anything.
8341 (The corresponding TEMPLATE_DECL is an
8342 instantiation, but the TYPE is not.) */
8343 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8345 /* Now, we call pushtag to put this NEWTAG into the scope of
8346 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8347 pushtag calling push_template_decl. We don't have to do
8348 this for enums because it will already have been done in
8351 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8352 pushtag (name, newtag, /*tag_scope=*/ts_current);
8355 else if (TREE_CODE (t) == FUNCTION_DECL
8356 || DECL_FUNCTION_TEMPLATE_P (t))
8358 /* Build new TYPE_METHODS. */
8361 if (TREE_CODE (t) == TEMPLATE_DECL)
8362 ++processing_template_decl;
8363 r = tsubst (t, args, tf_error, NULL_TREE);
8364 if (TREE_CODE (t) == TEMPLATE_DECL)
8365 --processing_template_decl;
8366 set_current_access_from_decl (r);
8367 finish_member_declaration (r);
8371 /* Build new TYPE_FIELDS. */
8372 if (TREE_CODE (t) == STATIC_ASSERT)
8375 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8376 tf_warning_or_error, NULL_TREE,
8377 /*integral_constant_expression_p=*/true);
8378 finish_static_assert (condition,
8379 STATIC_ASSERT_MESSAGE (t),
8380 STATIC_ASSERT_SOURCE_LOCATION (t),
8383 else if (TREE_CODE (t) != CONST_DECL)
8387 /* The file and line for this declaration, to
8388 assist in error message reporting. Since we
8389 called push_tinst_level above, we don't need to
8391 input_location = DECL_SOURCE_LOCATION (t);
8393 if (TREE_CODE (t) == TEMPLATE_DECL)
8394 ++processing_template_decl;
8395 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8396 if (TREE_CODE (t) == TEMPLATE_DECL)
8397 --processing_template_decl;
8398 if (TREE_CODE (r) == VAR_DECL)
8402 [t]he initialization (and any associated
8403 side-effects) of a static data member does
8404 not occur unless the static data member is
8405 itself used in a way that requires the
8406 definition of the static data member to
8409 Therefore, we do not substitute into the
8410 initialized for the static data member here. */
8411 finish_static_data_member_decl
8414 /*init_const_expr_p=*/false,
8415 /*asmspec_tree=*/NULL_TREE,
8417 if (DECL_INITIALIZED_IN_CLASS_P (r))
8418 check_static_variable_definition (r, TREE_TYPE (r));
8420 else if (TREE_CODE (r) == FIELD_DECL)
8422 /* Determine whether R has a valid type and can be
8423 completed later. If R is invalid, then it is
8424 replaced by error_mark_node so that it will not be
8425 added to TYPE_FIELDS. */
8426 tree rtype = TREE_TYPE (r);
8427 if (can_complete_type_without_circularity (rtype))
8428 complete_type (rtype);
8430 if (!COMPLETE_TYPE_P (rtype))
8432 cxx_incomplete_type_error (r, rtype);
8433 r = error_mark_node;
8437 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8438 such a thing will already have been added to the field
8439 list by tsubst_enum in finish_member_declaration in the
8440 CLASSTYPE_NESTED_UTDS case above. */
8441 if (!(TREE_CODE (r) == TYPE_DECL
8442 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8443 && DECL_ARTIFICIAL (r)))
8445 set_current_access_from_decl (r);
8446 finish_member_declaration (r);
8453 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8455 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8457 tree friend_type = t;
8458 bool adjust_processing_template_decl = false;
8460 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8462 /* template <class T> friend class C; */
8463 friend_type = tsubst_friend_class (friend_type, args);
8464 adjust_processing_template_decl = true;
8466 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8468 /* template <class T> friend class C::D; */
8469 friend_type = tsubst (friend_type, args,
8470 tf_warning_or_error, NULL_TREE);
8471 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8472 friend_type = TREE_TYPE (friend_type);
8473 adjust_processing_template_decl = true;
8475 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
8477 /* This could be either
8481 when dependent_type_p is false or
8483 template <class U> friend class T::C;
8486 friend_type = tsubst (friend_type, args,
8487 tf_warning_or_error, NULL_TREE);
8488 /* Bump processing_template_decl for correct
8489 dependent_type_p calculation. */
8490 ++processing_template_decl;
8491 if (dependent_type_p (friend_type))
8492 adjust_processing_template_decl = true;
8493 --processing_template_decl;
8495 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8496 && hidden_name_p (TYPE_NAME (friend_type)))
8500 where C hasn't been declared yet. Let's lookup name
8501 from namespace scope directly, bypassing any name that
8502 come from dependent base class. */
8503 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8505 /* The call to xref_tag_from_type does injection for friend
8507 push_nested_namespace (ns);
8509 xref_tag_from_type (friend_type, NULL_TREE,
8510 /*tag_scope=*/ts_current);
8511 pop_nested_namespace (ns);
8513 else if (uses_template_parms (friend_type))
8514 /* friend class C<T>; */
8515 friend_type = tsubst (friend_type, args,
8516 tf_warning_or_error, NULL_TREE);
8521 where C is already declared or
8523 friend class C<int>;
8525 We don't have to do anything in these cases. */
8527 if (adjust_processing_template_decl)
8528 /* Trick make_friend_class into realizing that the friend
8529 we're adding is a template, not an ordinary class. It's
8530 important that we use make_friend_class since it will
8531 perform some error-checking and output cross-reference
8533 ++processing_template_decl;
8535 if (friend_type != error_mark_node)
8536 make_friend_class (type, friend_type, /*complain=*/false);
8538 if (adjust_processing_template_decl)
8539 --processing_template_decl;
8543 /* Build new DECL_FRIENDLIST. */
8546 /* The file and line for this declaration, to
8547 assist in error message reporting. Since we
8548 called push_tinst_level above, we don't need to
8550 input_location = DECL_SOURCE_LOCATION (t);
8552 if (TREE_CODE (t) == TEMPLATE_DECL)
8554 ++processing_template_decl;
8555 push_deferring_access_checks (dk_no_check);
8558 r = tsubst_friend_function (t, args);
8559 add_friend (type, r, /*complain=*/false);
8560 if (TREE_CODE (t) == TEMPLATE_DECL)
8562 pop_deferring_access_checks ();
8563 --processing_template_decl;
8569 /* Set the file and line number information to whatever is given for
8570 the class itself. This puts error messages involving generated
8571 implicit functions at a predictable point, and the same point
8572 that would be used for non-template classes. */
8573 input_location = DECL_SOURCE_LOCATION (typedecl);
8575 unreverse_member_declarations (type);
8576 finish_struct_1 (type);
8577 TYPE_BEING_DEFINED (type) = 0;
8579 /* We don't instantiate default arguments for member functions. 14.7.1:
8581 The implicit instantiation of a class template specialization causes
8582 the implicit instantiation of the declarations, but not of the
8583 definitions or default arguments, of the class member functions,
8584 member classes, static data members and member templates.... */
8586 /* Some typedefs referenced from within the template code need to be access
8587 checked at template instantiation time, i.e now. These types were
8588 added to the template at parsing time. Let's get those and perform
8589 the access checks then. */
8590 perform_typedefs_access_check (pattern, args);
8591 perform_deferred_access_checks ();
8592 pop_nested_class ();
8593 maximum_field_alignment = saved_maximum_field_alignment;
8594 pop_from_top_level ();
8595 pop_deferring_access_checks ();
8598 /* The vtable for a template class can be emitted in any translation
8599 unit in which the class is instantiated. When there is no key
8600 method, however, finish_struct_1 will already have added TYPE to
8601 the keyed_classes list. */
8602 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8603 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8608 /* Wrapper for instantiate_class_template_1. */
8611 instantiate_class_template (tree type)
8614 timevar_push (TV_TEMPLATE_INST);
8615 ret = instantiate_class_template_1 (type);
8616 timevar_pop (TV_TEMPLATE_INST);
8621 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8627 else if (TYPE_P (t))
8628 r = tsubst (t, args, complain, in_decl);
8631 if (!(complain & tf_warning))
8632 ++c_inhibit_evaluation_warnings;
8633 r = tsubst_expr (t, args, complain, in_decl,
8634 /*integral_constant_expression_p=*/true);
8635 if (!(complain & tf_warning))
8636 --c_inhibit_evaluation_warnings;
8641 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8642 NONTYPE_ARGUMENT_PACK. */
8645 make_fnparm_pack (tree spec_parm)
8647 /* Collect all of the extra "packed" parameters into an
8651 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8652 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8653 int i, len = list_length (spec_parm);
8655 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8656 parmvec = make_tree_vec (len);
8657 parmtypevec = make_tree_vec (len);
8658 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8660 TREE_VEC_ELT (parmvec, i) = spec_parm;
8661 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8664 /* Build the argument packs. */
8665 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8666 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8667 TREE_TYPE (argpack) = argtypepack;
8672 /* Substitute ARGS into T, which is an pack expansion
8673 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8674 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8675 (if only a partial substitution could be performed) or
8676 ERROR_MARK_NODE if there was an error. */
8678 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8682 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8686 htab_t saved_local_specializations = NULL;
8688 gcc_assert (PACK_EXPANSION_P (t));
8689 pattern = PACK_EXPANSION_PATTERN (t);
8691 /* Determine the argument packs that will instantiate the parameter
8692 packs used in the expansion expression. While we're at it,
8693 compute the number of arguments to be expanded and make sure it
8695 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8696 pack = TREE_CHAIN (pack))
8698 tree parm_pack = TREE_VALUE (pack);
8699 tree arg_pack = NULL_TREE;
8700 tree orig_arg = NULL_TREE;
8702 if (TREE_CODE (parm_pack) == PARM_DECL)
8704 if (!cp_unevaluated_operand)
8705 arg_pack = retrieve_local_specialization (parm_pack);
8708 /* We can't rely on local_specializations for a parameter
8709 name used later in a function declaration (such as in a
8710 late-specified return type). Even if it exists, it might
8711 have the wrong value for a recursive call. Just make a
8712 dummy decl, since it's only used for its type. */
8713 arg_pack = tsubst_decl (parm_pack, args, complain);
8714 arg_pack = make_fnparm_pack (arg_pack);
8719 int level, idx, levels;
8720 template_parm_level_and_index (parm_pack, &level, &idx);
8722 levels = TMPL_ARGS_DEPTH (args);
8723 if (level <= levels)
8724 arg_pack = TMPL_ARG (args, level, idx);
8727 orig_arg = arg_pack;
8728 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8729 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8731 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8732 /* This can only happen if we forget to expand an argument
8733 pack somewhere else. Just return an error, silently. */
8735 result = make_tree_vec (1);
8736 TREE_VEC_ELT (result, 0) = error_mark_node;
8740 /* For clarity in the comments below let's use the
8741 representation 'argument_pack<elements>' to denote an
8742 argument pack and its elements.
8744 In the 'if' block below, we want to detect cases where
8745 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
8746 check if ARG_PACK is an argument pack which sole element is
8747 the expansion of PARM_PACK. That argument pack is typically
8748 created by template_parm_to_arg when passed a parameter
8751 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8752 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8754 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8755 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8756 /* So we have an argument_pack<P...>. We want to test if P
8757 is actually PARM_PACK. We will not use cp_tree_equal to
8758 test P and PARM_PACK because during type fixup (by
8759 fixup_template_parm) P can be a pre-fixup version of a
8760 type and PARM_PACK be its post-fixup version.
8761 cp_tree_equal would consider them as different even
8762 though we would want to consider them compatible for our
8763 precise purpose here.
8765 Thus we are going to consider that P and PARM_PACK are
8766 compatible if they have the same DECL. */
8767 if ((/* If ARG_PACK is a type parameter pack named by the
8768 same DECL as parm_pack ... */
8770 && TYPE_P (parm_pack)
8771 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
8772 /* ... or if ARG_PACK is a non-type parameter
8773 named by the same DECL as parm_pack ... */
8774 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
8775 && TREE_CODE (parm_pack) == PARM_DECL
8776 && TEMPLATE_PARM_DECL (pattern)
8777 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
8778 && template_parameter_pack_p (pattern))
8779 /* ... then the argument pack that the parameter maps to
8780 is just an expansion of the parameter itself, such as
8781 one would find in the implicit typedef of a class
8782 inside the class itself. Consider this parameter
8783 "unsubstituted", so that we will maintain the outer
8785 arg_pack = NULL_TREE;
8791 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8793 /* It's all-or-nothing with incomplete argument packs. */
8794 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8795 return error_mark_node;
8797 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8802 else if (len != my_len)
8805 /* We got explicit args for some packs but not others;
8806 do nothing now and try again after deduction. */
8808 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8809 error ("mismatched argument pack lengths while expanding "
8813 error ("mismatched argument pack lengths while expanding "
8816 return error_mark_node;
8819 /* Keep track of the parameter packs and their corresponding
8821 packs = tree_cons (parm_pack, arg_pack, packs);
8822 TREE_TYPE (packs) = orig_arg;
8825 /* We can't substitute for this parameter pack. */
8826 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8828 unsubstituted_packs);
8831 /* We cannot expand this expansion expression, because we don't have
8832 all of the argument packs we need. Substitute into the pattern
8833 and return a PACK_EXPANSION_*. The caller will need to deal with
8835 if (unsubstituted_packs)
8838 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8839 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8840 /*integral_constant_expression_p=*/false);
8842 new_pat = tsubst (pattern, args, complain, in_decl);
8843 return make_pack_expansion (new_pat);
8846 /* We could not find any argument packs that work. */
8848 return error_mark_node;
8850 if (cp_unevaluated_operand)
8852 /* We're in a late-specified return type, so create our own local
8853 specializations table; the current table is either NULL or (in the
8854 case of recursive unification) might have bindings that we don't
8855 want to use or alter. */
8856 saved_local_specializations = local_specializations;
8857 local_specializations = htab_create (37,
8858 hash_local_specialization,
8859 eq_local_specializations,
8863 /* For each argument in each argument pack, substitute into the
8865 result = make_tree_vec (len + incomplete);
8866 for (i = 0; i < len + incomplete; ++i)
8868 /* For parameter pack, change the substitution of the parameter
8869 pack to the ith argument in its argument pack, then expand
8871 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8873 tree parm = TREE_PURPOSE (pack);
8875 if (TREE_CODE (parm) == PARM_DECL)
8877 /* Select the Ith argument from the pack. */
8878 tree arg = make_node (ARGUMENT_PACK_SELECT);
8879 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8880 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8882 register_local_specialization (arg, parm);
8888 template_parm_level_and_index (parm, &level, &idx);
8892 /* Select the Ith argument from the pack. */
8893 value = make_node (ARGUMENT_PACK_SELECT);
8894 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8895 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8898 /* Update the corresponding argument. */
8899 TMPL_ARG (args, level, idx) = value;
8903 /* Substitute into the PATTERN with the altered arguments. */
8904 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8905 TREE_VEC_ELT (result, i) =
8906 tsubst_expr (pattern, args, complain, in_decl,
8907 /*integral_constant_expression_p=*/false);
8909 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8912 /* When we have incomplete argument packs, the last "expanded"
8913 result is itself a pack expansion, which allows us
8914 to deduce more arguments. */
8915 TREE_VEC_ELT (result, i) =
8916 make_pack_expansion (TREE_VEC_ELT (result, i));
8918 if (TREE_VEC_ELT (result, i) == error_mark_node)
8920 result = error_mark_node;
8925 /* Update ARGS to restore the substitution from parameter packs to
8926 their argument packs. */
8927 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8929 tree parm = TREE_PURPOSE (pack);
8931 if (TREE_CODE (parm) == PARM_DECL)
8932 register_local_specialization (TREE_TYPE (pack), parm);
8936 template_parm_level_and_index (parm, &level, &idx);
8938 /* Update the corresponding argument. */
8939 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8940 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8943 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8947 if (saved_local_specializations)
8949 htab_delete (local_specializations);
8950 local_specializations = saved_local_specializations;
8956 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8957 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8958 parameter packs; all parms generated from a function parameter pack will
8959 have the same DECL_PARM_INDEX. */
8962 get_pattern_parm (tree parm, tree tmpl)
8964 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8967 if (DECL_ARTIFICIAL (parm))
8969 for (patparm = DECL_ARGUMENTS (pattern);
8970 patparm; patparm = DECL_CHAIN (patparm))
8971 if (DECL_ARTIFICIAL (patparm)
8972 && DECL_NAME (parm) == DECL_NAME (patparm))
8977 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8978 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8979 gcc_assert (DECL_PARM_INDEX (patparm)
8980 == DECL_PARM_INDEX (parm));
8986 /* Substitute ARGS into the vector or list of template arguments T. */
8989 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8992 int len, need_new = 0, i, expanded_len_adjust = 0, out;
8995 if (t == error_mark_node)
8996 return error_mark_node;
8998 len = TREE_VEC_LENGTH (t);
8999 elts = XALLOCAVEC (tree, len);
9001 for (i = 0; i < len; i++)
9003 tree orig_arg = TREE_VEC_ELT (t, i);
9006 if (TREE_CODE (orig_arg) == TREE_VEC)
9007 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9008 else if (PACK_EXPANSION_P (orig_arg))
9010 /* Substitute into an expansion expression. */
9011 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9013 if (TREE_CODE (new_arg) == TREE_VEC)
9014 /* Add to the expanded length adjustment the number of
9015 expanded arguments. We subtract one from this
9016 measurement, because the argument pack expression
9017 itself is already counted as 1 in
9018 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9019 the argument pack is empty. */
9020 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9022 else if (ARGUMENT_PACK_P (orig_arg))
9024 /* Substitute into each of the arguments. */
9025 new_arg = TYPE_P (orig_arg)
9026 ? cxx_make_type (TREE_CODE (orig_arg))
9027 : make_node (TREE_CODE (orig_arg));
9029 SET_ARGUMENT_PACK_ARGS (
9031 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9032 args, complain, in_decl));
9034 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9035 new_arg = error_mark_node;
9037 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9038 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9040 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9042 if (TREE_TYPE (new_arg) == error_mark_node)
9043 new_arg = error_mark_node;
9047 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9049 if (new_arg == error_mark_node)
9050 return error_mark_node;
9053 if (new_arg != orig_arg)
9060 /* Make space for the expanded arguments coming from template
9062 t = make_tree_vec (len + expanded_len_adjust);
9063 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9064 arguments for a member template.
9065 In that case each TREE_VEC in ORIG_T represents a level of template
9066 arguments, and ORIG_T won't carry any non defaulted argument count.
9067 It will rather be the nested TREE_VECs that will carry one.
9068 In other words, ORIG_T carries a non defaulted argument count only
9069 if it doesn't contain any nested TREE_VEC. */
9070 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9072 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9073 count += expanded_len_adjust;
9074 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9076 for (i = 0, out = 0; i < len; i++)
9078 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9079 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9080 && TREE_CODE (elts[i]) == TREE_VEC)
9084 /* Now expand the template argument pack "in place". */
9085 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9086 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9090 TREE_VEC_ELT (t, out) = elts[i];
9098 /* Return the result of substituting ARGS into the template parameters
9099 given by PARMS. If there are m levels of ARGS and m + n levels of
9100 PARMS, then the result will contain n levels of PARMS. For
9101 example, if PARMS is `template <class T> template <class U>
9102 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9103 result will be `template <int*, double, class V>'. */
9106 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9111 /* When substituting into a template, we must set
9112 PROCESSING_TEMPLATE_DECL as the template parameters may be
9113 dependent if they are based on one-another, and the dependency
9114 predicates are short-circuit outside of templates. */
9115 ++processing_template_decl;
9117 for (new_parms = &r;
9118 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9119 new_parms = &(TREE_CHAIN (*new_parms)),
9120 parms = TREE_CHAIN (parms))
9123 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9126 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9130 if (parms == error_mark_node)
9133 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9135 if (tuple == error_mark_node)
9138 TREE_VEC_ELT (new_vec, i) =
9139 tsubst_template_parm (tuple, args, complain);
9143 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9144 - TMPL_ARGS_DEPTH (args)),
9145 new_vec, NULL_TREE);
9148 --processing_template_decl;
9153 /* Return the result of substituting ARGS into one template parameter
9154 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9155 parameter and which TREE_PURPOSE is the default argument of the
9156 template parameter. */
9159 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9161 tree default_value, parm_decl;
9163 if (args == NULL_TREE
9165 || t == error_mark_node)
9168 gcc_assert (TREE_CODE (t) == TREE_LIST);
9170 default_value = TREE_PURPOSE (t);
9171 parm_decl = TREE_VALUE (t);
9173 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9174 if (TREE_CODE (parm_decl) == PARM_DECL
9175 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9176 parm_decl = error_mark_node;
9177 default_value = tsubst_template_arg (default_value, args,
9178 complain, NULL_TREE);
9180 return build_tree_list (default_value, parm_decl);
9183 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9184 type T. If T is not an aggregate or enumeration type, it is
9185 handled as if by tsubst. IN_DECL is as for tsubst. If
9186 ENTERING_SCOPE is nonzero, T is the context for a template which
9187 we are presently tsubst'ing. Return the substituted value. */
9190 tsubst_aggr_type (tree t,
9192 tsubst_flags_t complain,
9199 switch (TREE_CODE (t))
9202 if (TYPE_PTRMEMFUNC_P (t))
9203 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9205 /* Else fall through. */
9208 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9213 int saved_unevaluated_operand;
9214 int saved_inhibit_evaluation_warnings;
9216 /* In "sizeof(X<I>)" we need to evaluate "I". */
9217 saved_unevaluated_operand = cp_unevaluated_operand;
9218 cp_unevaluated_operand = 0;
9219 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9220 c_inhibit_evaluation_warnings = 0;
9222 /* First, determine the context for the type we are looking
9224 context = TYPE_CONTEXT (t);
9227 context = tsubst_aggr_type (context, args, complain,
9228 in_decl, /*entering_scope=*/1);
9229 /* If context is a nested class inside a class template,
9230 it may still need to be instantiated (c++/33959). */
9231 if (TYPE_P (context))
9232 context = complete_type (context);
9235 /* Then, figure out what arguments are appropriate for the
9236 type we are trying to find. For example, given:
9238 template <class T> struct S;
9239 template <class T, class U> void f(T, U) { S<U> su; }
9241 and supposing that we are instantiating f<int, double>,
9242 then our ARGS will be {int, double}, but, when looking up
9243 S we only want {double}. */
9244 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9246 if (argvec == error_mark_node)
9247 r = error_mark_node;
9250 r = lookup_template_class (t, argvec, in_decl, context,
9251 entering_scope, complain);
9252 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9255 cp_unevaluated_operand = saved_unevaluated_operand;
9256 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9261 /* This is not a template type, so there's nothing to do. */
9265 return tsubst (t, args, complain, in_decl);
9269 /* Substitute into the default argument ARG (a default argument for
9270 FN), which has the indicated TYPE. */
9273 tsubst_default_argument (tree fn, tree type, tree arg)
9275 tree saved_class_ptr = NULL_TREE;
9276 tree saved_class_ref = NULL_TREE;
9278 /* This can happen in invalid code. */
9279 if (TREE_CODE (arg) == DEFAULT_ARG)
9282 /* This default argument came from a template. Instantiate the
9283 default argument here, not in tsubst. In the case of
9292 we must be careful to do name lookup in the scope of S<T>,
9293 rather than in the current class. */
9294 push_access_scope (fn);
9295 /* The "this" pointer is not valid in a default argument. */
9298 saved_class_ptr = current_class_ptr;
9299 cp_function_chain->x_current_class_ptr = NULL_TREE;
9300 saved_class_ref = current_class_ref;
9301 cp_function_chain->x_current_class_ref = NULL_TREE;
9304 push_deferring_access_checks(dk_no_deferred);
9305 /* The default argument expression may cause implicitly defined
9306 member functions to be synthesized, which will result in garbage
9307 collection. We must treat this situation as if we were within
9308 the body of function so as to avoid collecting live data on the
9311 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9312 tf_warning_or_error, NULL_TREE,
9313 /*integral_constant_expression_p=*/false);
9315 pop_deferring_access_checks();
9317 /* Restore the "this" pointer. */
9320 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9321 cp_function_chain->x_current_class_ref = saved_class_ref;
9324 /* Make sure the default argument is reasonable. */
9325 arg = check_default_argument (type, arg);
9327 pop_access_scope (fn);
9332 /* Substitute into all the default arguments for FN. */
9335 tsubst_default_arguments (tree fn)
9340 tmpl_args = DECL_TI_ARGS (fn);
9342 /* If this function is not yet instantiated, we certainly don't need
9343 its default arguments. */
9344 if (uses_template_parms (tmpl_args))
9346 /* Don't do this again for clones. */
9347 if (DECL_CLONED_FUNCTION_P (fn))
9350 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9352 arg = TREE_CHAIN (arg))
9353 if (TREE_PURPOSE (arg))
9354 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9356 TREE_PURPOSE (arg));
9359 /* Substitute the ARGS into the T, which is a _DECL. Return the
9360 result of the substitution. Issue error and warning messages under
9361 control of COMPLAIN. */
9364 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9366 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9367 location_t saved_loc;
9372 /* Set the filename and linenumber to improve error-reporting. */
9373 saved_loc = input_location;
9374 input_location = DECL_SOURCE_LOCATION (t);
9376 switch (TREE_CODE (t))
9380 /* We can get here when processing a member function template,
9381 member class template, or template template parameter. */
9382 tree decl = DECL_TEMPLATE_RESULT (t);
9387 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9389 /* Template template parameter is treated here. */
9390 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9391 if (new_type == error_mark_node)
9392 RETURN (error_mark_node);
9395 DECL_CHAIN (r) = NULL_TREE;
9396 TREE_TYPE (r) = new_type;
9397 DECL_TEMPLATE_RESULT (r)
9398 = build_decl (DECL_SOURCE_LOCATION (decl),
9399 TYPE_DECL, DECL_NAME (decl), new_type);
9400 DECL_TEMPLATE_PARMS (r)
9401 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9403 TYPE_NAME (new_type) = r;
9407 /* We might already have an instance of this template.
9408 The ARGS are for the surrounding class type, so the
9409 full args contain the tsubst'd args for the context,
9410 plus the innermost args from the template decl. */
9411 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9412 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9413 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9414 /* Because this is a template, the arguments will still be
9415 dependent, even after substitution. If
9416 PROCESSING_TEMPLATE_DECL is not set, the dependency
9417 predicates will short-circuit. */
9418 ++processing_template_decl;
9419 full_args = tsubst_template_args (tmpl_args, args,
9421 --processing_template_decl;
9422 if (full_args == error_mark_node)
9423 RETURN (error_mark_node);
9425 /* If this is a default template template argument,
9426 tsubst might not have changed anything. */
9427 if (full_args == tmpl_args)
9430 hash = hash_tmpl_and_args (t, full_args);
9431 spec = retrieve_specialization (t, full_args, hash);
9432 if (spec != NULL_TREE)
9438 /* Make a new template decl. It will be similar to the
9439 original, but will record the current template arguments.
9440 We also create a new function declaration, which is just
9441 like the old one, but points to this new template, rather
9442 than the old one. */
9444 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9445 DECL_CHAIN (r) = NULL_TREE;
9447 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9449 if (TREE_CODE (decl) == TYPE_DECL)
9452 ++processing_template_decl;
9453 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9454 --processing_template_decl;
9455 if (new_type == error_mark_node)
9456 RETURN (error_mark_node);
9458 TREE_TYPE (r) = new_type;
9459 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9460 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9461 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9462 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9467 ++processing_template_decl;
9468 new_decl = tsubst (decl, args, complain, in_decl);
9469 --processing_template_decl;
9470 if (new_decl == error_mark_node)
9471 RETURN (error_mark_node);
9473 DECL_TEMPLATE_RESULT (r) = new_decl;
9474 DECL_TI_TEMPLATE (new_decl) = r;
9475 TREE_TYPE (r) = TREE_TYPE (new_decl);
9476 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9477 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9480 SET_DECL_IMPLICIT_INSTANTIATION (r);
9481 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9482 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9484 /* The template parameters for this new template are all the
9485 template parameters for the old template, except the
9486 outermost level of parameters. */
9487 DECL_TEMPLATE_PARMS (r)
9488 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9491 if (PRIMARY_TEMPLATE_P (t))
9492 DECL_PRIMARY_TEMPLATE (r) = r;
9494 if (TREE_CODE (decl) != TYPE_DECL)
9495 /* Record this non-type partial instantiation. */
9496 register_specialization (r, t,
9497 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9505 tree argvec = NULL_TREE;
9513 /* Nobody should be tsubst'ing into non-template functions. */
9514 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9516 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9521 /* If T is not dependent, just return it. We have to
9522 increment PROCESSING_TEMPLATE_DECL because
9523 value_dependent_expression_p assumes that nothing is
9524 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9525 ++processing_template_decl;
9526 dependent_p = value_dependent_expression_p (t);
9527 --processing_template_decl;
9531 /* Calculate the most general template of which R is a
9532 specialization, and the complete set of arguments used to
9534 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9535 argvec = tsubst_template_args (DECL_TI_ARGS
9536 (DECL_TEMPLATE_RESULT
9537 (DECL_TI_TEMPLATE (t))),
9538 args, complain, in_decl);
9540 /* Check to see if we already have this specialization. */
9541 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9542 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9550 /* We can see more levels of arguments than parameters if
9551 there was a specialization of a member template, like
9554 template <class T> struct S { template <class U> void f(); }
9555 template <> template <class U> void S<int>::f(U);
9557 Here, we'll be substituting into the specialization,
9558 because that's where we can find the code we actually
9559 want to generate, but we'll have enough arguments for
9560 the most general template.
9562 We also deal with the peculiar case:
9564 template <class T> struct S {
9565 template <class U> friend void f();
9567 template <class U> void f() {}
9569 template void f<double>();
9571 Here, the ARGS for the instantiation of will be {int,
9572 double}. But, we only need as many ARGS as there are
9573 levels of template parameters in CODE_PATTERN. We are
9574 careful not to get fooled into reducing the ARGS in
9577 template <class T> struct S { template <class U> void f(U); }
9578 template <class T> template <> void S<T>::f(int) {}
9580 which we can spot because the pattern will be a
9581 specialization in this case. */
9582 args_depth = TMPL_ARGS_DEPTH (args);
9584 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9585 if (args_depth > parms_depth
9586 && !DECL_TEMPLATE_SPECIALIZATION (t))
9587 args = get_innermost_template_args (args, parms_depth);
9591 /* This special case arises when we have something like this:
9593 template <class T> struct S {
9594 friend void f<int>(int, double);
9597 Here, the DECL_TI_TEMPLATE for the friend declaration
9598 will be an IDENTIFIER_NODE. We are being called from
9599 tsubst_friend_function, and we want only to create a
9600 new decl (R) with appropriate types so that we can call
9601 determine_specialization. */
9602 gen_tmpl = NULL_TREE;
9605 if (DECL_CLASS_SCOPE_P (t))
9607 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9611 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9612 complain, t, /*entering_scope=*/1);
9617 ctx = DECL_CONTEXT (t);
9619 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9620 if (type == error_mark_node)
9621 RETURN (error_mark_node);
9623 /* We do NOT check for matching decls pushed separately at this
9624 point, as they may not represent instantiations of this
9625 template, and in any case are considered separate under the
9628 DECL_USE_TEMPLATE (r) = 0;
9629 TREE_TYPE (r) = type;
9630 /* Clear out the mangled name and RTL for the instantiation. */
9631 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9632 SET_DECL_RTL (r, NULL);
9633 /* Leave DECL_INITIAL set on deleted instantiations. */
9634 if (!DECL_DELETED_FN (r))
9635 DECL_INITIAL (r) = NULL_TREE;
9636 DECL_CONTEXT (r) = ctx;
9638 if (member && DECL_CONV_FN_P (r))
9639 /* Type-conversion operator. Reconstruct the name, in
9640 case it's the name of one of the template's parameters. */
9641 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9643 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9645 DECL_RESULT (r) = NULL_TREE;
9647 TREE_STATIC (r) = 0;
9648 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9649 DECL_EXTERNAL (r) = 1;
9650 /* If this is an instantiation of a function with internal
9651 linkage, we already know what object file linkage will be
9652 assigned to the instantiation. */
9653 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9654 DECL_DEFER_OUTPUT (r) = 0;
9655 DECL_CHAIN (r) = NULL_TREE;
9656 DECL_PENDING_INLINE_INFO (r) = 0;
9657 DECL_PENDING_INLINE_P (r) = 0;
9658 DECL_SAVED_TREE (r) = NULL_TREE;
9659 DECL_STRUCT_FUNCTION (r) = NULL;
9661 /* We'll re-clone as appropriate in instantiate_template. */
9662 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9664 /* If we aren't complaining now, return on error before we register
9665 the specialization so that we'll complain eventually. */
9666 if ((complain & tf_error) == 0
9667 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9668 && !grok_op_properties (r, /*complain=*/false))
9669 RETURN (error_mark_node);
9671 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9672 this in the special friend case mentioned above where
9673 GEN_TMPL is NULL. */
9676 DECL_TEMPLATE_INFO (r)
9677 = build_template_info (gen_tmpl, argvec);
9678 SET_DECL_IMPLICIT_INSTANTIATION (r);
9679 register_specialization (r, gen_tmpl, argvec, false, hash);
9681 /* We're not supposed to instantiate default arguments
9682 until they are called, for a template. But, for a
9685 template <class T> void f ()
9686 { extern void g(int i = T()); }
9688 we should do the substitution when the template is
9689 instantiated. We handle the member function case in
9690 instantiate_class_template since the default arguments
9691 might refer to other members of the class. */
9693 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9694 && !uses_template_parms (argvec))
9695 tsubst_default_arguments (r);
9698 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9700 /* Copy the list of befriending classes. */
9701 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9703 friends = &TREE_CHAIN (*friends))
9705 *friends = copy_node (*friends);
9706 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9711 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9713 maybe_retrofit_in_chrg (r);
9714 if (DECL_CONSTRUCTOR_P (r))
9715 grok_ctor_properties (ctx, r);
9716 /* If this is an instantiation of a member template, clone it.
9717 If it isn't, that'll be handled by
9718 clone_constructors_and_destructors. */
9719 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9720 clone_function_decl (r, /*update_method_vec_p=*/0);
9722 else if ((complain & tf_error) != 0
9723 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9724 && !grok_op_properties (r, /*complain=*/true))
9725 RETURN (error_mark_node);
9727 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9728 SET_DECL_FRIEND_CONTEXT (r,
9729 tsubst (DECL_FRIEND_CONTEXT (t),
9730 args, complain, in_decl));
9732 /* Possibly limit visibility based on template args. */
9733 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9734 if (DECL_VISIBILITY_SPECIFIED (t))
9736 DECL_VISIBILITY_SPECIFIED (r) = 0;
9738 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9740 determine_visibility (r);
9741 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9742 && !processing_template_decl)
9743 defaulted_late_check (r);
9745 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9746 args, complain, in_decl);
9752 tree type = NULL_TREE;
9754 tree expanded_types = NULL_TREE;
9755 tree prev_r = NULL_TREE;
9756 tree first_r = NULL_TREE;
9758 if (FUNCTION_PARAMETER_PACK_P (t))
9760 /* If there is a local specialization that isn't a
9761 parameter pack, it means that we're doing a "simple"
9762 substitution from inside tsubst_pack_expansion. Just
9763 return the local specialization (which will be a single
9765 tree spec = retrieve_local_specialization (t);
9767 && TREE_CODE (spec) == PARM_DECL
9768 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9771 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9772 the parameters in this function parameter pack. */
9773 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9775 if (TREE_CODE (expanded_types) == TREE_VEC)
9777 len = TREE_VEC_LENGTH (expanded_types);
9779 /* Zero-length parameter packs are boring. Just substitute
9782 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9787 /* All we did was update the type. Make a note of that. */
9788 type = expanded_types;
9789 expanded_types = NULL_TREE;
9793 /* Loop through all of the parameter's we'll build. When T is
9794 a function parameter pack, LEN is the number of expanded
9795 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9797 for (i = 0; i < len; ++i)
9801 if (DECL_TEMPLATE_PARM_P (t))
9802 SET_DECL_TEMPLATE_PARM_P (r);
9804 /* An argument of a function parameter pack is not a parameter
9806 FUNCTION_PARAMETER_PACK_P (r) = false;
9809 /* We're on the Ith parameter of the function parameter
9812 /* Get the Ith type. */
9813 type = TREE_VEC_ELT (expanded_types, i);
9816 /* Rename the parameter to include the index. */
9818 make_ith_pack_parameter_name (DECL_NAME (r), i);
9821 /* We're dealing with a normal parameter. */
9822 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9824 type = type_decays_to (type);
9825 TREE_TYPE (r) = type;
9826 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9828 if (DECL_INITIAL (r))
9830 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9831 DECL_INITIAL (r) = TREE_TYPE (r);
9833 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9837 DECL_CONTEXT (r) = NULL_TREE;
9839 if (!DECL_TEMPLATE_PARM_P (r))
9840 DECL_ARG_TYPE (r) = type_passed_as (type);
9842 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9843 args, complain, in_decl);
9845 /* Keep track of the first new parameter we
9846 generate. That's what will be returned to the
9851 /* Build a proper chain of parameters when substituting
9852 into a function parameter pack. */
9854 DECL_CHAIN (prev_r) = r;
9858 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9859 complain, DECL_CHAIN (t));
9861 /* FIRST_R contains the start of the chain we've built. */
9871 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9872 if (type == error_mark_node)
9873 RETURN (error_mark_node);
9874 TREE_TYPE (r) = type;
9875 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9877 /* DECL_INITIAL gives the number of bits in a bit-field. */
9879 = tsubst_expr (DECL_INITIAL (t), args,
9881 /*integral_constant_expression_p=*/true);
9882 /* We don't have to set DECL_CONTEXT here; it is set by
9883 finish_member_declaration. */
9884 DECL_CHAIN (r) = NULL_TREE;
9885 if (VOID_TYPE_P (type))
9886 error ("instantiation of %q+D as type %qT", r, type);
9888 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9889 args, complain, in_decl);
9894 /* We reach here only for member using decls. */
9895 if (DECL_DEPENDENT_P (t))
9897 r = do_class_using_decl
9898 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9899 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9901 r = error_mark_node;
9904 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9905 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9911 DECL_CHAIN (r) = NULL_TREE;
9918 tree argvec = NULL_TREE;
9919 tree gen_tmpl = NULL_TREE;
9921 tree tmpl = NULL_TREE;
9923 tree type = NULL_TREE;
9926 if (TREE_CODE (t) == TYPE_DECL
9927 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9929 /* If this is the canonical decl, we don't have to
9930 mess with instantiations, and often we can't (for
9931 typename, template type parms and such). Note that
9932 TYPE_NAME is not correct for the above test if
9933 we've copied the type for a typedef. */
9934 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9935 if (type == error_mark_node)
9936 RETURN (error_mark_node);
9937 r = TYPE_NAME (type);
9941 /* Check to see if we already have the specialization we
9944 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9946 /* T is a static data member or namespace-scope entity.
9947 We have to substitute into namespace-scope variables
9948 (even though such entities are never templates) because
9951 template <class T> void f() { extern T t; }
9953 where the entity referenced is not known until
9954 instantiation time. */
9956 ctx = DECL_CONTEXT (t);
9957 if (DECL_CLASS_SCOPE_P (t))
9959 ctx = tsubst_aggr_type (ctx, args,
9961 in_decl, /*entering_scope=*/1);
9962 /* If CTX is unchanged, then T is in fact the
9963 specialization we want. That situation occurs when
9964 referencing a static data member within in its own
9965 class. We can use pointer equality, rather than
9966 same_type_p, because DECL_CONTEXT is always
9968 if (ctx == DECL_CONTEXT (t))
9974 tmpl = DECL_TI_TEMPLATE (t);
9975 gen_tmpl = most_general_template (tmpl);
9976 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9977 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9978 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9983 /* A local variable. */
9985 /* Subsequent calls to pushdecl will fill this in. */
9987 spec = retrieve_local_specialization (t);
9989 /* If we already have the specialization we need, there is
9990 nothing more to do. */
9997 /* Create a new node for the specialization we need. */
9999 if (type == NULL_TREE)
10001 if (is_typedef_decl (t))
10002 type = DECL_ORIGINAL_TYPE (t);
10004 type = TREE_TYPE (t);
10005 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10006 type = strip_array_domain (type);
10007 type = tsubst (type, args, complain, in_decl);
10009 if (TREE_CODE (r) == VAR_DECL)
10011 /* Even if the original location is out of scope, the
10012 newly substituted one is not. */
10013 DECL_DEAD_FOR_LOCAL (r) = 0;
10014 DECL_INITIALIZED_P (r) = 0;
10015 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10016 if (type == error_mark_node)
10017 RETURN (error_mark_node);
10018 if (TREE_CODE (type) == FUNCTION_TYPE)
10020 /* It may seem that this case cannot occur, since:
10025 declares a function, not a variable. However:
10028 template <typename T> void g() { T t; }
10029 template void g<f>();
10031 is an attempt to declare a variable with function
10033 error ("variable %qD has function type",
10034 /* R is not yet sufficiently initialized, so we
10035 just use its name. */
10037 RETURN (error_mark_node);
10039 type = complete_type (type);
10040 /* Wait until cp_finish_decl to set this again, to handle
10041 circular dependency (template/instantiate6.C). */
10042 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10043 type = check_var_type (DECL_NAME (r), type);
10045 if (DECL_HAS_VALUE_EXPR_P (t))
10047 tree ve = DECL_VALUE_EXPR (t);
10048 ve = tsubst_expr (ve, args, complain, in_decl,
10049 /*constant_expression_p=*/false);
10050 SET_DECL_VALUE_EXPR (r, ve);
10053 else if (DECL_SELF_REFERENCE_P (t))
10054 SET_DECL_SELF_REFERENCE_P (r);
10055 TREE_TYPE (r) = type;
10056 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10057 DECL_CONTEXT (r) = ctx;
10058 /* Clear out the mangled name and RTL for the instantiation. */
10059 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10060 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10061 SET_DECL_RTL (r, NULL);
10062 /* The initializer must not be expanded until it is required;
10063 see [temp.inst]. */
10064 DECL_INITIAL (r) = NULL_TREE;
10065 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10066 SET_DECL_RTL (r, NULL);
10067 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10068 if (TREE_CODE (r) == VAR_DECL)
10070 /* Possibly limit visibility based on template args. */
10071 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10072 if (DECL_VISIBILITY_SPECIFIED (t))
10074 DECL_VISIBILITY_SPECIFIED (r) = 0;
10075 DECL_ATTRIBUTES (r)
10076 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10078 determine_visibility (r);
10083 /* A static data member declaration is always marked
10084 external when it is declared in-class, even if an
10085 initializer is present. We mimic the non-template
10086 processing here. */
10087 DECL_EXTERNAL (r) = 1;
10089 register_specialization (r, gen_tmpl, argvec, false, hash);
10090 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10091 SET_DECL_IMPLICIT_INSTANTIATION (r);
10093 else if (cp_unevaluated_operand)
10095 /* We're substituting this var in a decltype outside of its
10096 scope, such as for a lambda return type. Don't add it to
10097 local_specializations, do perform auto deduction. */
10098 tree auto_node = type_uses_auto (type);
10100 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10101 /*constant_expression_p=*/false);
10103 if (auto_node && init)
10105 init = resolve_nondeduced_context (init);
10106 if (describable_type (init))
10108 type = do_auto_deduction (type, init, auto_node);
10109 TREE_TYPE (r) = type;
10114 register_local_specialization (r, t);
10116 DECL_CHAIN (r) = NULL_TREE;
10118 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10120 args, complain, in_decl);
10122 /* Preserve a typedef that names a type. */
10123 if (is_typedef_decl (r))
10125 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10126 set_underlying_type (r);
10129 layout_decl (r, 0);
10134 gcc_unreachable ();
10139 /* Restore the file and line information. */
10140 input_location = saved_loc;
10145 /* Substitute into the ARG_TYPES of a function type. */
10148 tsubst_arg_types (tree arg_types,
10150 tsubst_flags_t complain,
10153 tree remaining_arg_types;
10154 tree type = NULL_TREE;
10156 tree expanded_args = NULL_TREE;
10159 if (!arg_types || arg_types == void_list_node)
10162 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10163 args, complain, in_decl);
10164 if (remaining_arg_types == error_mark_node)
10165 return error_mark_node;
10167 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10169 /* For a pack expansion, perform substitution on the
10170 entire expression. Later on, we'll handle the arguments
10172 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10173 args, complain, in_decl);
10175 if (TREE_CODE (expanded_args) == TREE_VEC)
10176 /* So that we'll spin through the parameters, one by one. */
10177 i = TREE_VEC_LENGTH (expanded_args);
10180 /* We only partially substituted into the parameter
10181 pack. Our type is TYPE_PACK_EXPANSION. */
10182 type = expanded_args;
10183 expanded_args = NULL_TREE;
10191 type = TREE_VEC_ELT (expanded_args, i);
10193 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10195 if (type == error_mark_node)
10196 return error_mark_node;
10197 if (VOID_TYPE_P (type))
10199 if (complain & tf_error)
10201 error ("invalid parameter type %qT", type);
10203 error ("in declaration %q+D", in_decl);
10205 return error_mark_node;
10208 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10209 top-level qualifiers as required. */
10210 type = TYPE_MAIN_VARIANT (type_decays_to (type));
10212 /* We do not substitute into default arguments here. The standard
10213 mandates that they be instantiated only when needed, which is
10214 done in build_over_call. */
10215 default_arg = TREE_PURPOSE (arg_types);
10217 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10219 /* We've instantiated a template before its default arguments
10220 have been parsed. This can happen for a nested template
10221 class, and is not an error unless we require the default
10222 argument in a call of this function. */
10223 remaining_arg_types =
10224 tree_cons (default_arg, type, remaining_arg_types);
10225 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10226 remaining_arg_types);
10229 remaining_arg_types =
10230 hash_tree_cons (default_arg, type, remaining_arg_types);
10233 return remaining_arg_types;
10236 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10237 *not* handle the exception-specification for FNTYPE, because the
10238 initial substitution of explicitly provided template parameters
10239 during argument deduction forbids substitution into the
10240 exception-specification:
10244 All references in the function type of the function template to the
10245 corresponding template parameters are replaced by the specified tem-
10246 plate argument values. If a substitution in a template parameter or
10247 in the function type of the function template results in an invalid
10248 type, type deduction fails. [Note: The equivalent substitution in
10249 exception specifications is done only when the function is instanti-
10250 ated, at which point a program is ill-formed if the substitution
10251 results in an invalid type.] */
10254 tsubst_function_type (tree t,
10256 tsubst_flags_t complain,
10263 /* The TYPE_CONTEXT is not used for function/method types. */
10264 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10266 /* Substitute the return type. */
10267 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10268 if (return_type == error_mark_node)
10269 return error_mark_node;
10270 /* The standard does not presently indicate that creation of a
10271 function type with an invalid return type is a deduction failure.
10272 However, that is clearly analogous to creating an array of "void"
10273 or a reference to a reference. This is core issue #486. */
10274 if (TREE_CODE (return_type) == ARRAY_TYPE
10275 || TREE_CODE (return_type) == FUNCTION_TYPE)
10277 if (complain & tf_error)
10279 if (TREE_CODE (return_type) == ARRAY_TYPE)
10280 error ("function returning an array");
10282 error ("function returning a function");
10284 return error_mark_node;
10287 /* Substitute the argument types. */
10288 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10289 complain, in_decl);
10290 if (arg_types == error_mark_node)
10291 return error_mark_node;
10293 /* Construct a new type node and return it. */
10294 if (TREE_CODE (t) == FUNCTION_TYPE)
10296 fntype = build_function_type (return_type, arg_types);
10297 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10301 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10302 if (! MAYBE_CLASS_TYPE_P (r))
10306 Type deduction may fail for any of the following
10309 -- Attempting to create "pointer to member of T" when T
10310 is not a class type. */
10311 if (complain & tf_error)
10312 error ("creating pointer to member function of non-class type %qT",
10314 return error_mark_node;
10317 fntype = build_method_type_directly (r, return_type,
10318 TREE_CHAIN (arg_types));
10320 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10325 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10326 ARGS into that specification, and return the substituted
10327 specification. If there is no specification, return NULL_TREE. */
10330 tsubst_exception_specification (tree fntype,
10332 tsubst_flags_t complain,
10338 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10339 new_specs = NULL_TREE;
10340 if (specs && TREE_PURPOSE (specs))
10342 /* A noexcept-specifier. */
10343 new_specs = tsubst_copy_and_build
10344 (TREE_PURPOSE (specs), args, complain, in_decl, /*function_p=*/false,
10345 /*integral_constant_expression_p=*/true);
10346 new_specs = build_noexcept_spec (new_specs, complain);
10350 if (! TREE_VALUE (specs))
10357 tree expanded_specs = NULL_TREE;
10359 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10361 /* Expand the pack expansion type. */
10362 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10366 if (expanded_specs == error_mark_node)
10367 return error_mark_node;
10368 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10369 len = TREE_VEC_LENGTH (expanded_specs);
10372 /* We're substituting into a member template, so
10373 we got a TYPE_PACK_EXPANSION back. Add that
10374 expansion and move on. */
10375 gcc_assert (TREE_CODE (expanded_specs)
10376 == TYPE_PACK_EXPANSION);
10377 new_specs = add_exception_specifier (new_specs,
10380 specs = TREE_CHAIN (specs);
10385 for (i = 0; i < len; ++i)
10387 if (expanded_specs)
10388 spec = TREE_VEC_ELT (expanded_specs, i);
10390 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10391 if (spec == error_mark_node)
10393 new_specs = add_exception_specifier (new_specs, spec,
10397 specs = TREE_CHAIN (specs);
10403 /* Take the tree structure T and replace template parameters used
10404 therein with the argument vector ARGS. IN_DECL is an associated
10405 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10406 Issue error and warning messages under control of COMPLAIN. Note
10407 that we must be relatively non-tolerant of extensions here, in
10408 order to preserve conformance; if we allow substitutions that
10409 should not be allowed, we may allow argument deductions that should
10410 not succeed, and therefore report ambiguous overload situations
10411 where there are none. In theory, we could allow the substitution,
10412 but indicate that it should have failed, and allow our caller to
10413 make sure that the right thing happens, but we don't try to do this
10416 This function is used for dealing with types, decls and the like;
10417 for expressions, use tsubst_expr or tsubst_copy. */
10420 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10422 enum tree_code code;
10425 if (t == NULL_TREE || t == error_mark_node
10426 || t == integer_type_node
10427 || t == void_type_node
10428 || t == char_type_node
10429 || t == unknown_type_node
10430 || TREE_CODE (t) == NAMESPACE_DECL
10431 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10435 return tsubst_decl (t, args, complain);
10437 if (args == NULL_TREE)
10440 code = TREE_CODE (t);
10442 if (code == IDENTIFIER_NODE)
10443 type = IDENTIFIER_TYPE_VALUE (t);
10445 type = TREE_TYPE (t);
10447 gcc_assert (type != unknown_type_node);
10449 /* Reuse typedefs. We need to do this to handle dependent attributes,
10450 such as attribute aligned. */
10452 && typedef_variant_p (t))
10454 tree decl = TYPE_NAME (t);
10456 if (DECL_CLASS_SCOPE_P (decl)
10457 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10458 && uses_template_parms (DECL_CONTEXT (decl)))
10460 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10461 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10462 r = retrieve_specialization (tmpl, gen_args, 0);
10464 else if (DECL_FUNCTION_SCOPE_P (decl)
10465 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10466 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10467 r = retrieve_local_specialization (decl);
10469 /* The typedef is from a non-template context. */
10475 r = cp_build_qualified_type_real
10476 (r, cp_type_quals (t) | cp_type_quals (r),
10477 complain | tf_ignore_bad_quals);
10480 /* Else we must be instantiating the typedef, so fall through. */
10484 && code != TYPENAME_TYPE
10485 && code != TEMPLATE_TYPE_PARM
10486 && code != IDENTIFIER_NODE
10487 && code != FUNCTION_TYPE
10488 && code != METHOD_TYPE)
10489 type = tsubst (type, args, complain, in_decl);
10490 if (type == error_mark_node)
10491 return error_mark_node;
10497 case ENUMERAL_TYPE:
10498 return tsubst_aggr_type (t, args, complain, in_decl,
10499 /*entering_scope=*/0);
10502 case IDENTIFIER_NODE:
10513 if (t == integer_type_node)
10516 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10517 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10521 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10523 max = tsubst_expr (omax, args, complain, in_decl,
10524 /*integral_constant_expression_p=*/false);
10526 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10528 if (TREE_CODE (max) == NOP_EXPR
10529 && TREE_SIDE_EFFECTS (omax)
10530 && !TREE_TYPE (max))
10531 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10533 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10534 with TREE_SIDE_EFFECTS that indicates this is not an integral
10535 constant expression. */
10536 if (processing_template_decl
10537 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10539 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10540 TREE_SIDE_EFFECTS (max) = 1;
10543 return compute_array_index_type (NULL_TREE, max, complain);
10546 case TEMPLATE_TYPE_PARM:
10547 case TEMPLATE_TEMPLATE_PARM:
10548 case BOUND_TEMPLATE_TEMPLATE_PARM:
10549 case TEMPLATE_PARM_INDEX:
10554 tree arg = NULL_TREE;
10558 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10559 template_parm_level_and_index (t, &level, &idx);
10561 levels = TMPL_ARGS_DEPTH (args);
10562 if (level <= levels)
10564 arg = TMPL_ARG (args, level, idx);
10566 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10567 /* See through ARGUMENT_PACK_SELECT arguments. */
10568 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10571 if (arg == error_mark_node)
10572 return error_mark_node;
10573 else if (arg != NULL_TREE)
10575 if (ARGUMENT_PACK_P (arg))
10576 /* If ARG is an argument pack, we don't actually want to
10577 perform a substitution here, because substitutions
10578 for argument packs are only done
10579 element-by-element. We can get to this point when
10580 substituting the type of a non-type template
10581 parameter pack, when that type actually contains
10582 template parameter packs from an outer template, e.g.,
10584 template<typename... Types> struct A {
10585 template<Types... Values> struct B { };
10589 if (code == TEMPLATE_TYPE_PARM)
10592 gcc_assert (TYPE_P (arg));
10594 quals = cp_type_quals (arg) | cp_type_quals (t);
10596 return cp_build_qualified_type_real
10597 (arg, quals, complain | tf_ignore_bad_quals);
10599 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10601 /* We are processing a type constructed from a
10602 template template parameter. */
10603 tree argvec = tsubst (TYPE_TI_ARGS (t),
10604 args, complain, in_decl);
10605 if (argvec == error_mark_node)
10606 return error_mark_node;
10608 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10609 are resolving nested-types in the signature of a
10610 member function templates. Otherwise ARG is a
10611 TEMPLATE_DECL and is the real template to be
10613 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10614 arg = TYPE_NAME (arg);
10616 r = lookup_template_class (arg,
10618 DECL_CONTEXT (arg),
10619 /*entering_scope=*/0,
10621 return cp_build_qualified_type_real
10622 (r, cp_type_quals (t), complain);
10625 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10626 return unshare_expr (arg);
10630 /* This can happen during the attempted tsubst'ing in
10631 unify. This means that we don't yet have any information
10632 about the template parameter in question. */
10635 /* If we get here, we must have been looking at a parm for a
10636 more deeply nested template. Make a new version of this
10637 template parameter, but with a lower level. */
10640 case TEMPLATE_TYPE_PARM:
10641 case TEMPLATE_TEMPLATE_PARM:
10642 case BOUND_TEMPLATE_TEMPLATE_PARM:
10643 if (cp_type_quals (t))
10645 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10646 r = cp_build_qualified_type_real
10647 (r, cp_type_quals (t),
10648 complain | (code == TEMPLATE_TYPE_PARM
10649 ? tf_ignore_bad_quals : 0));
10654 TEMPLATE_TYPE_PARM_INDEX (r)
10655 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10656 r, levels, args, complain);
10657 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10658 TYPE_MAIN_VARIANT (r) = r;
10659 TYPE_POINTER_TO (r) = NULL_TREE;
10660 TYPE_REFERENCE_TO (r) = NULL_TREE;
10662 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10663 /* We have reduced the level of the template
10664 template parameter, but not the levels of its
10665 template parameters, so canonical_type_parameter
10666 will not be able to find the canonical template
10667 template parameter for this level. Thus, we
10668 require structural equality checking to compare
10669 TEMPLATE_TEMPLATE_PARMs. */
10670 SET_TYPE_STRUCTURAL_EQUALITY (r);
10671 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10672 SET_TYPE_STRUCTURAL_EQUALITY (r);
10674 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10676 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10678 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10679 complain, in_decl);
10680 if (argvec == error_mark_node)
10681 return error_mark_node;
10683 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10684 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10689 case TEMPLATE_PARM_INDEX:
10690 r = reduce_template_parm_level (t, type, levels, args, complain);
10694 gcc_unreachable ();
10702 tree purpose, value, chain;
10704 if (t == void_list_node)
10707 purpose = TREE_PURPOSE (t);
10710 purpose = tsubst (purpose, args, complain, in_decl);
10711 if (purpose == error_mark_node)
10712 return error_mark_node;
10714 value = TREE_VALUE (t);
10717 value = tsubst (value, args, complain, in_decl);
10718 if (value == error_mark_node)
10719 return error_mark_node;
10721 chain = TREE_CHAIN (t);
10722 if (chain && chain != void_type_node)
10724 chain = tsubst (chain, args, complain, in_decl);
10725 if (chain == error_mark_node)
10726 return error_mark_node;
10728 if (purpose == TREE_PURPOSE (t)
10729 && value == TREE_VALUE (t)
10730 && chain == TREE_CHAIN (t))
10732 return hash_tree_cons (purpose, value, chain);
10736 /* We should never be tsubsting a binfo. */
10737 gcc_unreachable ();
10740 /* A vector of template arguments. */
10741 gcc_assert (!type);
10742 return tsubst_template_args (t, args, complain, in_decl);
10745 case REFERENCE_TYPE:
10747 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10752 Type deduction may fail for any of the following
10755 -- Attempting to create a pointer to reference type.
10756 -- Attempting to create a reference to a reference type or
10757 a reference to void.
10759 Core issue 106 says that creating a reference to a reference
10760 during instantiation is no longer a cause for failure. We
10761 only enforce this check in strict C++98 mode. */
10762 if ((TREE_CODE (type) == REFERENCE_TYPE
10763 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10764 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10766 static location_t last_loc;
10768 /* We keep track of the last time we issued this error
10769 message to avoid spewing a ton of messages during a
10770 single bad template instantiation. */
10771 if (complain & tf_error
10772 && last_loc != input_location)
10774 if (TREE_CODE (type) == VOID_TYPE)
10775 error ("forming reference to void");
10776 else if (code == POINTER_TYPE)
10777 error ("forming pointer to reference type %qT", type);
10779 error ("forming reference to reference type %qT", type);
10780 last_loc = input_location;
10783 return error_mark_node;
10785 else if (code == POINTER_TYPE)
10787 r = build_pointer_type (type);
10788 if (TREE_CODE (type) == METHOD_TYPE)
10789 r = build_ptrmemfunc_type (r);
10791 else if (TREE_CODE (type) == REFERENCE_TYPE)
10792 /* In C++0x, during template argument substitution, when there is an
10793 attempt to create a reference to a reference type, reference
10794 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10796 "If a template-argument for a template-parameter T names a type
10797 that is a reference to a type A, an attempt to create the type
10798 'lvalue reference to cv T' creates the type 'lvalue reference to
10799 A,' while an attempt to create the type type rvalue reference to
10800 cv T' creates the type T"
10802 r = cp_build_reference_type
10804 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10806 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10807 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10809 if (r != error_mark_node)
10810 /* Will this ever be needed for TYPE_..._TO values? */
10817 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10818 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10822 Type deduction may fail for any of the following
10825 -- Attempting to create "pointer to member of T" when T
10826 is not a class type. */
10827 if (complain & tf_error)
10828 error ("creating pointer to member of non-class type %qT", r);
10829 return error_mark_node;
10831 if (TREE_CODE (type) == REFERENCE_TYPE)
10833 if (complain & tf_error)
10834 error ("creating pointer to member reference type %qT", type);
10835 return error_mark_node;
10837 if (TREE_CODE (type) == VOID_TYPE)
10839 if (complain & tf_error)
10840 error ("creating pointer to member of type void");
10841 return error_mark_node;
10843 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10844 if (TREE_CODE (type) == FUNCTION_TYPE)
10846 /* The type of the implicit object parameter gets its
10847 cv-qualifiers from the FUNCTION_TYPE. */
10849 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10850 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10851 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10855 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10859 case FUNCTION_TYPE:
10864 fntype = tsubst_function_type (t, args, complain, in_decl);
10865 if (fntype == error_mark_node)
10866 return error_mark_node;
10868 /* Substitute the exception specification. */
10869 specs = tsubst_exception_specification (t, args, complain,
10871 if (specs == error_mark_node)
10872 return error_mark_node;
10874 fntype = build_exception_variant (fntype, specs);
10879 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10880 if (domain == error_mark_node)
10881 return error_mark_node;
10883 /* As an optimization, we avoid regenerating the array type if
10884 it will obviously be the same as T. */
10885 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10888 /* These checks should match the ones in grokdeclarator.
10892 The deduction may fail for any of the following reasons:
10894 -- Attempting to create an array with an element type that
10895 is void, a function type, or a reference type, or [DR337]
10896 an abstract class type. */
10897 if (TREE_CODE (type) == VOID_TYPE
10898 || TREE_CODE (type) == FUNCTION_TYPE
10899 || TREE_CODE (type) == REFERENCE_TYPE)
10901 if (complain & tf_error)
10902 error ("creating array of %qT", type);
10903 return error_mark_node;
10905 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10907 if (complain & tf_error)
10908 error ("creating array of %qT, which is an abstract class type",
10910 return error_mark_node;
10913 r = build_cplus_array_type (type, domain);
10915 if (TYPE_USER_ALIGN (t))
10917 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10918 TYPE_USER_ALIGN (r) = 1;
10924 case TYPENAME_TYPE:
10926 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10927 in_decl, /*entering_scope=*/1);
10928 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10929 complain, in_decl);
10931 if (ctx == error_mark_node || f == error_mark_node)
10932 return error_mark_node;
10934 if (!MAYBE_CLASS_TYPE_P (ctx))
10936 if (complain & tf_error)
10937 error ("%qT is not a class, struct, or union type", ctx);
10938 return error_mark_node;
10940 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10942 /* Normally, make_typename_type does not require that the CTX
10943 have complete type in order to allow things like:
10945 template <class T> struct S { typename S<T>::X Y; };
10947 But, such constructs have already been resolved by this
10948 point, so here CTX really should have complete type, unless
10949 it's a partial instantiation. */
10950 ctx = complete_type (ctx);
10951 if (!COMPLETE_TYPE_P (ctx))
10953 if (complain & tf_error)
10954 cxx_incomplete_type_error (NULL_TREE, ctx);
10955 return error_mark_node;
10959 f = make_typename_type (ctx, f, typename_type,
10960 (complain & tf_error) | tf_keep_type_decl);
10961 if (f == error_mark_node)
10963 if (TREE_CODE (f) == TYPE_DECL)
10965 complain |= tf_ignore_bad_quals;
10969 if (TREE_CODE (f) != TYPENAME_TYPE)
10971 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10973 if (complain & tf_error)
10974 error ("%qT resolves to %qT, which is not an enumeration type",
10977 return error_mark_node;
10979 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10981 if (complain & tf_error)
10982 error ("%qT resolves to %qT, which is is not a class type",
10985 return error_mark_node;
10989 return cp_build_qualified_type_real
10990 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10993 case UNBOUND_CLASS_TEMPLATE:
10995 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10996 in_decl, /*entering_scope=*/1);
10997 tree name = TYPE_IDENTIFIER (t);
10998 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11000 if (ctx == error_mark_node || name == error_mark_node)
11001 return error_mark_node;
11004 parm_list = tsubst_template_parms (parm_list, args, complain);
11005 return make_unbound_class_template (ctx, name, parm_list, complain);
11012 ++cp_unevaluated_operand;
11013 ++c_inhibit_evaluation_warnings;
11015 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11017 /*integral_constant_expression_p=*/false);
11019 --cp_unevaluated_operand;
11020 --c_inhibit_evaluation_warnings;
11022 type = finish_typeof (type);
11023 return cp_build_qualified_type_real (type,
11025 | cp_type_quals (type),
11029 case DECLTYPE_TYPE:
11033 ++cp_unevaluated_operand;
11034 ++c_inhibit_evaluation_warnings;
11036 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11038 /*integral_constant_expression_p=*/false);
11040 --cp_unevaluated_operand;
11041 --c_inhibit_evaluation_warnings;
11043 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11044 type = lambda_capture_field_type (type);
11045 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
11046 type = lambda_return_type (type);
11048 type = finish_decltype_type
11049 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11050 return cp_build_qualified_type_real (type,
11052 | cp_type_quals (type),
11056 case UNDERLYING_TYPE:
11058 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11059 complain, in_decl);
11060 return finish_underlying_type (type);
11063 case TYPE_ARGUMENT_PACK:
11064 case NONTYPE_ARGUMENT_PACK:
11066 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11068 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11072 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11074 /* For template nontype argument packs, also substitute into
11076 if (code == NONTYPE_ARGUMENT_PACK)
11077 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11095 /* We should use one of the expression tsubsts for these codes. */
11096 gcc_unreachable ();
11099 sorry ("use of %qs in template", tree_code_name [(int) code]);
11100 return error_mark_node;
11104 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11105 type of the expression on the left-hand side of the "." or "->"
11109 tsubst_baselink (tree baselink, tree object_type,
11110 tree args, tsubst_flags_t complain, tree in_decl)
11113 tree qualifying_scope;
11116 tree template_args = 0;
11117 bool template_id_p = false;
11119 /* A baselink indicates a function from a base class. Both the
11120 BASELINK_ACCESS_BINFO and the base class referenced may
11121 indicate bases of the template class, rather than the
11122 instantiated class. In addition, lookups that were not
11123 ambiguous before may be ambiguous now. Therefore, we perform
11124 the lookup again. */
11125 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11126 qualifying_scope = tsubst (qualifying_scope, args,
11127 complain, in_decl);
11128 fns = BASELINK_FUNCTIONS (baselink);
11129 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11130 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11132 template_id_p = true;
11133 template_args = TREE_OPERAND (fns, 1);
11134 fns = TREE_OPERAND (fns, 0);
11136 template_args = tsubst_template_args (template_args, args,
11137 complain, in_decl);
11139 name = DECL_NAME (get_first_fn (fns));
11140 if (IDENTIFIER_TYPENAME_P (name))
11141 name = mangle_conv_op_name_for_type (optype);
11142 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11144 return error_mark_node;
11146 /* If lookup found a single function, mark it as used at this
11147 point. (If it lookup found multiple functions the one selected
11148 later by overload resolution will be marked as used at that
11150 if (BASELINK_P (baselink))
11151 fns = BASELINK_FUNCTIONS (baselink);
11152 if (!template_id_p && !really_overloaded_fn (fns))
11153 mark_used (OVL_CURRENT (fns));
11155 /* Add back the template arguments, if present. */
11156 if (BASELINK_P (baselink) && template_id_p)
11157 BASELINK_FUNCTIONS (baselink)
11158 = build_nt (TEMPLATE_ID_EXPR,
11159 BASELINK_FUNCTIONS (baselink),
11161 /* Update the conversion operator type. */
11162 BASELINK_OPTYPE (baselink) = optype;
11165 object_type = current_class_type;
11166 return adjust_result_of_qualified_name_lookup (baselink,
11171 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11172 true if the qualified-id will be a postfix-expression in-and-of
11173 itself; false if more of the postfix-expression follows the
11174 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11178 tsubst_qualified_id (tree qualified_id, tree args,
11179 tsubst_flags_t complain, tree in_decl,
11180 bool done, bool address_p)
11186 tree template_args;
11188 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11190 /* Figure out what name to look up. */
11191 name = TREE_OPERAND (qualified_id, 1);
11192 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11194 is_template = true;
11195 template_args = TREE_OPERAND (name, 1);
11197 template_args = tsubst_template_args (template_args, args,
11198 complain, in_decl);
11199 name = TREE_OPERAND (name, 0);
11203 is_template = false;
11204 template_args = NULL_TREE;
11207 /* Substitute into the qualifying scope. When there are no ARGS, we
11208 are just trying to simplify a non-dependent expression. In that
11209 case the qualifying scope may be dependent, and, in any case,
11210 substituting will not help. */
11211 scope = TREE_OPERAND (qualified_id, 0);
11214 scope = tsubst (scope, args, complain, in_decl);
11215 expr = tsubst_copy (name, args, complain, in_decl);
11220 if (dependent_scope_p (scope))
11221 return build_qualified_name (NULL_TREE, scope, expr,
11222 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11224 if (!BASELINK_P (name) && !DECL_P (expr))
11226 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11228 /* A BIT_NOT_EXPR is used to represent a destructor. */
11229 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11231 error ("qualifying type %qT does not match destructor name ~%qT",
11232 scope, TREE_OPERAND (expr, 0));
11233 expr = error_mark_node;
11236 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11237 /*is_type_p=*/0, false);
11240 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11241 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11242 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11244 if (complain & tf_error)
11246 error ("dependent-name %qE is parsed as a non-type, but "
11247 "instantiation yields a type", qualified_id);
11248 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11250 return error_mark_node;
11256 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11258 /* Remember that there was a reference to this entity. */
11262 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11264 if (complain & tf_error)
11265 qualified_name_lookup_error (scope,
11266 TREE_OPERAND (qualified_id, 1),
11267 expr, input_location);
11268 return error_mark_node;
11272 expr = lookup_template_function (expr, template_args);
11274 if (expr == error_mark_node && complain & tf_error)
11275 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11276 expr, input_location);
11277 else if (TYPE_P (scope))
11279 expr = (adjust_result_of_qualified_name_lookup
11280 (expr, scope, current_class_type));
11281 expr = (finish_qualified_id_expr
11282 (scope, expr, done, address_p,
11283 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11284 /*template_arg_p=*/false));
11287 /* Expressions do not generally have reference type. */
11288 if (TREE_CODE (expr) != SCOPE_REF
11289 /* However, if we're about to form a pointer-to-member, we just
11290 want the referenced member referenced. */
11291 && TREE_CODE (expr) != OFFSET_REF)
11292 expr = convert_from_reference (expr);
11297 /* Like tsubst, but deals with expressions. This function just replaces
11298 template parms; to finish processing the resultant expression, use
11302 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11304 enum tree_code code;
11307 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11310 code = TREE_CODE (t);
11315 r = retrieve_local_specialization (t);
11320 /* This can happen for a parameter name used later in a function
11321 declaration (such as in a late-specified return type). Just
11322 make a dummy decl, since it's only used for its type. */
11323 gcc_assert (cp_unevaluated_operand != 0);
11324 /* We copy T because want to tsubst the PARM_DECL only,
11325 not the following PARM_DECLs that are chained to T. */
11327 r = tsubst_decl (c, args, complain);
11328 /* Give it the template pattern as its context; its true context
11329 hasn't been instantiated yet and this is good enough for
11331 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11334 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11335 r = ARGUMENT_PACK_SELECT_ARG (r);
11344 if (DECL_TEMPLATE_PARM_P (t))
11345 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11346 /* There is no need to substitute into namespace-scope
11348 if (DECL_NAMESPACE_SCOPE_P (t))
11350 /* If ARGS is NULL, then T is known to be non-dependent. */
11351 if (args == NULL_TREE)
11352 return integral_constant_value (t);
11354 /* Unfortunately, we cannot just call lookup_name here.
11357 template <int I> int f() {
11359 struct S { void g() { E e = a; } };
11362 When we instantiate f<7>::S::g(), say, lookup_name is not
11363 clever enough to find f<7>::a. */
11365 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11366 /*entering_scope=*/0);
11368 for (v = TYPE_VALUES (enum_type);
11370 v = TREE_CHAIN (v))
11371 if (TREE_PURPOSE (v) == DECL_NAME (t))
11372 return TREE_VALUE (v);
11374 /* We didn't find the name. That should never happen; if
11375 name-lookup found it during preliminary parsing, we
11376 should find it again here during instantiation. */
11377 gcc_unreachable ();
11382 if (DECL_CONTEXT (t))
11386 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11387 /*entering_scope=*/1);
11388 if (ctx != DECL_CONTEXT (t))
11390 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11393 if (complain & tf_error)
11394 error ("using invalid field %qD", t);
11395 return error_mark_node;
11404 case FUNCTION_DECL:
11405 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11406 || local_variable_p (t))
11407 t = tsubst (t, args, complain, in_decl);
11412 /* An OVERLOAD will always be a non-dependent overload set; an
11413 overload set from function scope will just be represented with an
11414 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11415 gcc_assert (!uses_template_parms (t));
11419 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11421 case TEMPLATE_DECL:
11422 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11423 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11424 args, complain, in_decl);
11425 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11426 return tsubst (t, args, complain, in_decl);
11427 else if (DECL_CLASS_SCOPE_P (t)
11428 && uses_template_parms (DECL_CONTEXT (t)))
11430 /* Template template argument like the following example need
11433 template <template <class> class TT> struct C {};
11434 template <class T> struct D {
11435 template <class U> struct E {};
11440 We are processing the template argument `E' in #1 for
11441 the template instantiation #2. Originally, `E' is a
11442 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11443 have to substitute this with one having context `D<int>'. */
11445 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11446 return lookup_field (context, DECL_NAME(t), 0, false);
11449 /* Ordinary template template argument. */
11453 case REINTERPRET_CAST_EXPR:
11454 case CONST_CAST_EXPR:
11455 case STATIC_CAST_EXPR:
11456 case DYNAMIC_CAST_EXPR:
11459 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11460 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11463 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11469 ++cp_unevaluated_operand;
11470 ++c_inhibit_evaluation_warnings;
11471 /* We only want to compute the number of arguments. */
11472 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11473 complain, in_decl);
11474 --cp_unevaluated_operand;
11475 --c_inhibit_evaluation_warnings;
11477 if (TREE_CODE (expanded) == TREE_VEC)
11478 len = TREE_VEC_LENGTH (expanded);
11480 if (expanded == error_mark_node)
11481 return error_mark_node;
11482 else if (PACK_EXPANSION_P (expanded)
11483 || (TREE_CODE (expanded) == TREE_VEC
11485 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11487 if (TREE_CODE (expanded) == TREE_VEC)
11488 expanded = TREE_VEC_ELT (expanded, len - 1);
11490 if (TYPE_P (expanded))
11491 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11492 complain & tf_error);
11494 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11495 complain & tf_error);
11498 return build_int_cst (size_type_node, len);
11504 case TRUTH_NOT_EXPR:
11507 case UNARY_PLUS_EXPR: /* Unary + */
11509 case AT_ENCODE_EXPR:
11513 case REALPART_EXPR:
11514 case IMAGPART_EXPR:
11516 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11517 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11519 case COMPONENT_REF:
11524 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11525 name = TREE_OPERAND (t, 1);
11526 if (TREE_CODE (name) == BIT_NOT_EXPR)
11528 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11529 complain, in_decl);
11530 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11532 else if (TREE_CODE (name) == SCOPE_REF
11533 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11535 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11536 complain, in_decl);
11537 name = TREE_OPERAND (name, 1);
11538 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11539 complain, in_decl);
11540 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11541 name = build_qualified_name (/*type=*/NULL_TREE,
11543 /*template_p=*/false);
11545 else if (TREE_CODE (name) == BASELINK)
11546 name = tsubst_baselink (name,
11547 non_reference (TREE_TYPE (object)),
11551 name = tsubst_copy (name, args, complain, in_decl);
11552 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11558 case TRUNC_DIV_EXPR:
11559 case CEIL_DIV_EXPR:
11560 case FLOOR_DIV_EXPR:
11561 case ROUND_DIV_EXPR:
11562 case EXACT_DIV_EXPR:
11566 case TRUNC_MOD_EXPR:
11567 case FLOOR_MOD_EXPR:
11568 case TRUTH_ANDIF_EXPR:
11569 case TRUTH_ORIF_EXPR:
11570 case TRUTH_AND_EXPR:
11571 case TRUTH_OR_EXPR:
11584 case COMPOUND_EXPR:
11587 case PREDECREMENT_EXPR:
11588 case PREINCREMENT_EXPR:
11589 case POSTDECREMENT_EXPR:
11590 case POSTINCREMENT_EXPR:
11592 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11593 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11596 return build_qualified_name (/*type=*/NULL_TREE,
11597 tsubst_copy (TREE_OPERAND (t, 0),
11598 args, complain, in_decl),
11599 tsubst_copy (TREE_OPERAND (t, 1),
11600 args, complain, in_decl),
11601 QUALIFIED_NAME_IS_TEMPLATE (t));
11606 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11607 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11608 NULL_TREE, NULL_TREE);
11612 int n = VL_EXP_OPERAND_LENGTH (t);
11613 tree result = build_vl_exp (CALL_EXPR, n);
11615 for (i = 0; i < n; i++)
11616 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11617 complain, in_decl);
11623 case PSEUDO_DTOR_EXPR:
11626 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11627 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11628 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11629 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11636 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11637 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11638 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11639 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11646 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11647 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11648 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11649 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11653 case TEMPLATE_ID_EXPR:
11655 /* Substituted template arguments */
11656 tree fn = TREE_OPERAND (t, 0);
11657 tree targs = TREE_OPERAND (t, 1);
11659 fn = tsubst_copy (fn, args, complain, in_decl);
11661 targs = tsubst_template_args (targs, args, complain, in_decl);
11663 return lookup_template_function (fn, targs);
11668 tree purpose, value, chain;
11670 if (t == void_list_node)
11673 purpose = TREE_PURPOSE (t);
11675 purpose = tsubst_copy (purpose, args, complain, in_decl);
11676 value = TREE_VALUE (t);
11678 value = tsubst_copy (value, args, complain, in_decl);
11679 chain = TREE_CHAIN (t);
11680 if (chain && chain != void_type_node)
11681 chain = tsubst_copy (chain, args, complain, in_decl);
11682 if (purpose == TREE_PURPOSE (t)
11683 && value == TREE_VALUE (t)
11684 && chain == TREE_CHAIN (t))
11686 return tree_cons (purpose, value, chain);
11691 case ENUMERAL_TYPE:
11693 case TEMPLATE_TYPE_PARM:
11694 case TEMPLATE_TEMPLATE_PARM:
11695 case BOUND_TEMPLATE_TEMPLATE_PARM:
11696 case TEMPLATE_PARM_INDEX:
11698 case REFERENCE_TYPE:
11700 case FUNCTION_TYPE:
11703 case TYPENAME_TYPE:
11704 case UNBOUND_CLASS_TEMPLATE:
11706 case DECLTYPE_TYPE:
11708 return tsubst (t, args, complain, in_decl);
11710 case IDENTIFIER_NODE:
11711 if (IDENTIFIER_TYPENAME_P (t))
11713 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11714 return mangle_conv_op_name_for_type (new_type);
11720 /* This is handled by tsubst_copy_and_build. */
11721 gcc_unreachable ();
11724 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11726 tsubst (TREE_TYPE (t), args, complain, in_decl));
11728 case CLEANUP_POINT_EXPR:
11729 /* We shouldn't have built any of these during initial template
11730 generation. Instead, they should be built during instantiation
11731 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11732 gcc_unreachable ();
11736 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11737 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11738 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11739 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11740 mark_used (TREE_OPERAND (r, 1));
11743 case EXPR_PACK_EXPANSION:
11744 error ("invalid use of pack expansion expression");
11745 return error_mark_node;
11747 case NONTYPE_ARGUMENT_PACK:
11748 error ("use %<...%> to expand argument pack");
11749 return error_mark_node;
11756 /* Instantiate any typedefs in the type. */
11757 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11758 r = fold_convert (type, t);
11759 gcc_assert (TREE_CODE (r) == code);
11764 /* These can sometimes show up in a partial instantiation, but never
11765 involve template parms. */
11766 gcc_assert (!uses_template_parms (t));
11770 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
11771 gcc_checking_assert (false);
11776 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11779 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11782 tree new_clauses = NULL, nc, oc;
11784 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11786 nc = copy_node (oc);
11787 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11790 switch (OMP_CLAUSE_CODE (nc))
11792 case OMP_CLAUSE_LASTPRIVATE:
11793 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11795 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11796 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11797 in_decl, /*integral_constant_expression_p=*/false);
11798 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11799 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11802 case OMP_CLAUSE_PRIVATE:
11803 case OMP_CLAUSE_SHARED:
11804 case OMP_CLAUSE_FIRSTPRIVATE:
11805 case OMP_CLAUSE_REDUCTION:
11806 case OMP_CLAUSE_COPYIN:
11807 case OMP_CLAUSE_COPYPRIVATE:
11808 case OMP_CLAUSE_IF:
11809 case OMP_CLAUSE_NUM_THREADS:
11810 case OMP_CLAUSE_SCHEDULE:
11811 case OMP_CLAUSE_COLLAPSE:
11812 OMP_CLAUSE_OPERAND (nc, 0)
11813 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11814 in_decl, /*integral_constant_expression_p=*/false);
11816 case OMP_CLAUSE_NOWAIT:
11817 case OMP_CLAUSE_ORDERED:
11818 case OMP_CLAUSE_DEFAULT:
11819 case OMP_CLAUSE_UNTIED:
11822 gcc_unreachable ();
11826 return finish_omp_clauses (nreverse (new_clauses));
11829 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11832 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11835 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11837 tree purpose, value, chain;
11842 if (TREE_CODE (t) != TREE_LIST)
11843 return tsubst_copy_and_build (t, args, complain, in_decl,
11844 /*function_p=*/false,
11845 /*integral_constant_expression_p=*/false);
11847 if (t == void_list_node)
11850 purpose = TREE_PURPOSE (t);
11852 purpose = RECUR (purpose);
11853 value = TREE_VALUE (t);
11854 if (value && TREE_CODE (value) != LABEL_DECL)
11855 value = RECUR (value);
11856 chain = TREE_CHAIN (t);
11857 if (chain && chain != void_type_node)
11858 chain = RECUR (chain);
11859 return tree_cons (purpose, value, chain);
11863 /* Substitute one OMP_FOR iterator. */
11866 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11867 tree condv, tree incrv, tree *clauses,
11868 tree args, tsubst_flags_t complain, tree in_decl,
11869 bool integral_constant_expression_p)
11871 #define RECUR(NODE) \
11872 tsubst_expr ((NODE), args, complain, in_decl, \
11873 integral_constant_expression_p)
11874 tree decl, init, cond, incr, auto_node;
11876 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11877 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11878 decl = RECUR (TREE_OPERAND (init, 0));
11879 init = TREE_OPERAND (init, 1);
11880 auto_node = type_uses_auto (TREE_TYPE (decl));
11881 if (auto_node && init)
11883 tree init_expr = init;
11884 if (TREE_CODE (init_expr) == DECL_EXPR)
11885 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11886 init_expr = RECUR (init_expr);
11888 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11890 gcc_assert (!type_dependent_expression_p (decl));
11892 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11894 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11895 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11896 if (TREE_CODE (incr) == MODIFY_EXPR)
11897 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11898 RECUR (TREE_OPERAND (incr, 1)),
11901 incr = RECUR (incr);
11902 TREE_VEC_ELT (declv, i) = decl;
11903 TREE_VEC_ELT (initv, i) = init;
11904 TREE_VEC_ELT (condv, i) = cond;
11905 TREE_VEC_ELT (incrv, i) = incr;
11909 if (init && TREE_CODE (init) != DECL_EXPR)
11912 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11914 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11915 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11916 && OMP_CLAUSE_DECL (c) == decl)
11918 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11919 && OMP_CLAUSE_DECL (c) == decl)
11920 error ("iteration variable %qD should not be firstprivate", decl);
11921 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11922 && OMP_CLAUSE_DECL (c) == decl)
11923 error ("iteration variable %qD should not be reduction", decl);
11927 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11928 OMP_CLAUSE_DECL (c) = decl;
11929 c = finish_omp_clauses (c);
11932 OMP_CLAUSE_CHAIN (c) = *clauses;
11937 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11938 if (COMPARISON_CLASS_P (cond))
11939 cond = build2 (TREE_CODE (cond), boolean_type_node,
11940 RECUR (TREE_OPERAND (cond, 0)),
11941 RECUR (TREE_OPERAND (cond, 1)));
11943 cond = RECUR (cond);
11944 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11945 switch (TREE_CODE (incr))
11947 case PREINCREMENT_EXPR:
11948 case PREDECREMENT_EXPR:
11949 case POSTINCREMENT_EXPR:
11950 case POSTDECREMENT_EXPR:
11951 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11952 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11955 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11956 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11958 tree rhs = TREE_OPERAND (incr, 1);
11959 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11960 RECUR (TREE_OPERAND (incr, 0)),
11961 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11962 RECUR (TREE_OPERAND (rhs, 0)),
11963 RECUR (TREE_OPERAND (rhs, 1))));
11966 incr = RECUR (incr);
11969 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11970 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11972 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11973 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11974 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11975 TREE_TYPE (decl), lhs,
11976 RECUR (TREE_OPERAND (incr, 2))));
11978 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11979 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11980 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11982 tree rhs = TREE_OPERAND (incr, 2);
11983 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11984 RECUR (TREE_OPERAND (incr, 0)),
11985 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11986 RECUR (TREE_OPERAND (rhs, 0)),
11987 RECUR (TREE_OPERAND (rhs, 1))));
11990 incr = RECUR (incr);
11993 incr = RECUR (incr);
11997 TREE_VEC_ELT (declv, i) = decl;
11998 TREE_VEC_ELT (initv, i) = init;
11999 TREE_VEC_ELT (condv, i) = cond;
12000 TREE_VEC_ELT (incrv, i) = incr;
12004 /* Like tsubst_copy for expressions, etc. but also does semantic
12008 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12009 bool integral_constant_expression_p)
12011 #define RECUR(NODE) \
12012 tsubst_expr ((NODE), args, complain, in_decl, \
12013 integral_constant_expression_p)
12017 if (t == NULL_TREE || t == error_mark_node)
12020 if (EXPR_HAS_LOCATION (t))
12021 input_location = EXPR_LOCATION (t);
12022 if (STATEMENT_CODE_P (TREE_CODE (t)))
12023 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12025 switch (TREE_CODE (t))
12027 case STATEMENT_LIST:
12029 tree_stmt_iterator i;
12030 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12031 RECUR (tsi_stmt (i));
12035 case CTOR_INITIALIZER:
12036 finish_mem_initializers (tsubst_initializer_list
12037 (TREE_OPERAND (t, 0), args));
12041 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12045 tmp = RECUR (EXPR_STMT_EXPR (t));
12046 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12047 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12049 finish_expr_stmt (tmp);
12053 do_using_directive (USING_STMT_NAMESPACE (t));
12058 tree decl, pattern_decl;
12061 pattern_decl = decl = DECL_EXPR_DECL (t);
12062 if (TREE_CODE (decl) == LABEL_DECL)
12063 finish_label_decl (DECL_NAME (decl));
12064 else if (TREE_CODE (decl) == USING_DECL)
12066 tree scope = USING_DECL_SCOPE (decl);
12067 tree name = DECL_NAME (decl);
12070 scope = tsubst (scope, args, complain, in_decl);
12071 decl = lookup_qualified_name (scope, name,
12072 /*is_type_p=*/false,
12073 /*complain=*/false);
12074 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12075 qualified_name_lookup_error (scope, name, decl, input_location);
12077 do_local_using_decl (decl, scope, name);
12081 init = DECL_INITIAL (decl);
12082 decl = tsubst (decl, args, complain, in_decl);
12083 if (decl != error_mark_node)
12085 /* By marking the declaration as instantiated, we avoid
12086 trying to instantiate it. Since instantiate_decl can't
12087 handle local variables, and since we've already done
12088 all that needs to be done, that's the right thing to
12090 if (TREE_CODE (decl) == VAR_DECL)
12091 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12092 if (TREE_CODE (decl) == VAR_DECL
12093 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12094 /* Anonymous aggregates are a special case. */
12095 finish_anon_union (decl);
12098 int const_init = false;
12099 maybe_push_decl (decl);
12100 if (TREE_CODE (decl) == VAR_DECL
12101 && DECL_PRETTY_FUNCTION_P (decl))
12103 /* For __PRETTY_FUNCTION__ we have to adjust the
12105 const char *const name
12106 = cxx_printable_name (current_function_decl, 2);
12107 init = cp_fname_init (name, &TREE_TYPE (decl));
12111 tree t = RECUR (init);
12115 /* If we had an initializer but it
12116 instantiated to nothing,
12117 value-initialize the object. This will
12118 only occur when the initializer was a
12119 pack expansion where the parameter packs
12120 used in that expansion were of length
12122 init = build_value_init (TREE_TYPE (decl),
12124 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12125 init = get_target_expr_sfinae (init, complain);
12131 if (TREE_CODE (decl) == VAR_DECL)
12132 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12134 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12139 /* A DECL_EXPR can also be used as an expression, in the condition
12140 clause of an if/for/while construct. */
12145 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12146 RECUR (FOR_INIT_STMT (t));
12147 finish_for_init_stmt (stmt);
12148 tmp = RECUR (FOR_COND (t));
12149 finish_for_cond (tmp, stmt);
12150 tmp = RECUR (FOR_EXPR (t));
12151 finish_for_expr (tmp, stmt);
12152 RECUR (FOR_BODY (t));
12153 finish_for_stmt (stmt);
12156 case RANGE_FOR_STMT:
12159 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12160 decl = RANGE_FOR_DECL (t);
12161 decl = tsubst (decl, args, complain, in_decl);
12162 maybe_push_decl (decl);
12163 expr = RECUR (RANGE_FOR_EXPR (t));
12164 stmt = cp_convert_range_for (stmt, decl, expr);
12165 RECUR (RANGE_FOR_BODY (t));
12166 finish_for_stmt (stmt);
12171 stmt = begin_while_stmt ();
12172 tmp = RECUR (WHILE_COND (t));
12173 finish_while_stmt_cond (tmp, stmt);
12174 RECUR (WHILE_BODY (t));
12175 finish_while_stmt (stmt);
12179 stmt = begin_do_stmt ();
12180 RECUR (DO_BODY (t));
12181 finish_do_body (stmt);
12182 tmp = RECUR (DO_COND (t));
12183 finish_do_stmt (tmp, stmt);
12187 stmt = begin_if_stmt ();
12188 tmp = RECUR (IF_COND (t));
12189 finish_if_stmt_cond (tmp, stmt);
12190 RECUR (THEN_CLAUSE (t));
12191 finish_then_clause (stmt);
12193 if (ELSE_CLAUSE (t))
12195 begin_else_clause (stmt);
12196 RECUR (ELSE_CLAUSE (t));
12197 finish_else_clause (stmt);
12200 finish_if_stmt (stmt);
12204 if (BIND_EXPR_BODY_BLOCK (t))
12205 stmt = begin_function_body ();
12207 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12208 ? BCS_TRY_BLOCK : 0);
12210 RECUR (BIND_EXPR_BODY (t));
12212 if (BIND_EXPR_BODY_BLOCK (t))
12213 finish_function_body (stmt);
12215 finish_compound_stmt (stmt);
12219 finish_break_stmt ();
12222 case CONTINUE_STMT:
12223 finish_continue_stmt ();
12227 stmt = begin_switch_stmt ();
12228 tmp = RECUR (SWITCH_STMT_COND (t));
12229 finish_switch_cond (tmp, stmt);
12230 RECUR (SWITCH_STMT_BODY (t));
12231 finish_switch_stmt (stmt);
12234 case CASE_LABEL_EXPR:
12235 finish_case_label (EXPR_LOCATION (t),
12236 RECUR (CASE_LOW (t)),
12237 RECUR (CASE_HIGH (t)));
12242 tree decl = LABEL_EXPR_LABEL (t);
12245 label = finish_label_stmt (DECL_NAME (decl));
12246 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12247 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12252 tmp = GOTO_DESTINATION (t);
12253 if (TREE_CODE (tmp) != LABEL_DECL)
12254 /* Computed goto's must be tsubst'd into. On the other hand,
12255 non-computed gotos must not be; the identifier in question
12256 will have no binding. */
12259 tmp = DECL_NAME (tmp);
12260 finish_goto_stmt (tmp);
12264 tmp = finish_asm_stmt
12265 (ASM_VOLATILE_P (t),
12266 RECUR (ASM_STRING (t)),
12267 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12268 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12269 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12270 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12272 tree asm_expr = tmp;
12273 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12274 asm_expr = TREE_OPERAND (asm_expr, 0);
12275 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12282 stmt = begin_try_block ();
12283 RECUR (TRY_STMTS (t));
12284 finish_cleanup_try_block (stmt);
12285 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12289 tree compound_stmt = NULL_TREE;
12291 if (FN_TRY_BLOCK_P (t))
12292 stmt = begin_function_try_block (&compound_stmt);
12294 stmt = begin_try_block ();
12296 RECUR (TRY_STMTS (t));
12298 if (FN_TRY_BLOCK_P (t))
12299 finish_function_try_block (stmt);
12301 finish_try_block (stmt);
12303 RECUR (TRY_HANDLERS (t));
12304 if (FN_TRY_BLOCK_P (t))
12305 finish_function_handler_sequence (stmt, compound_stmt);
12307 finish_handler_sequence (stmt);
12313 tree decl = HANDLER_PARMS (t);
12317 decl = tsubst (decl, args, complain, in_decl);
12318 /* Prevent instantiate_decl from trying to instantiate
12319 this variable. We've already done all that needs to be
12321 if (decl != error_mark_node)
12322 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12324 stmt = begin_handler ();
12325 finish_handler_parms (decl, stmt);
12326 RECUR (HANDLER_BODY (t));
12327 finish_handler (stmt);
12332 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12335 case STATIC_ASSERT:
12338 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12341 /*integral_constant_expression_p=*/true);
12342 finish_static_assert (condition,
12343 STATIC_ASSERT_MESSAGE (t),
12344 STATIC_ASSERT_SOURCE_LOCATION (t),
12345 /*member_p=*/false);
12350 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12351 args, complain, in_decl);
12352 stmt = begin_omp_parallel ();
12353 RECUR (OMP_PARALLEL_BODY (t));
12354 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12355 = OMP_PARALLEL_COMBINED (t);
12359 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12360 args, complain, in_decl);
12361 stmt = begin_omp_task ();
12362 RECUR (OMP_TASK_BODY (t));
12363 finish_omp_task (tmp, stmt);
12368 tree clauses, body, pre_body;
12369 tree declv, initv, condv, incrv;
12372 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12373 args, complain, in_decl);
12374 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12375 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12376 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12377 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12379 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12380 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12381 &clauses, args, complain, in_decl,
12382 integral_constant_expression_p);
12384 stmt = begin_omp_structured_block ();
12386 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12387 if (TREE_VEC_ELT (initv, i) == NULL
12388 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12389 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12390 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12392 tree init = RECUR (TREE_VEC_ELT (initv, i));
12393 gcc_assert (init == TREE_VEC_ELT (declv, i));
12394 TREE_VEC_ELT (initv, i) = NULL_TREE;
12398 tree decl_expr = TREE_VEC_ELT (initv, i);
12399 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12400 gcc_assert (init != NULL);
12401 TREE_VEC_ELT (initv, i) = RECUR (init);
12402 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12404 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12407 pre_body = push_stmt_list ();
12408 RECUR (OMP_FOR_PRE_BODY (t));
12409 pre_body = pop_stmt_list (pre_body);
12411 body = push_stmt_list ();
12412 RECUR (OMP_FOR_BODY (t));
12413 body = pop_stmt_list (body);
12415 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12416 body, pre_body, clauses);
12418 add_stmt (finish_omp_structured_block (stmt));
12424 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12425 stmt = push_stmt_list ();
12426 RECUR (OMP_BODY (t));
12427 stmt = pop_stmt_list (stmt);
12430 OMP_BODY (t) = stmt;
12431 OMP_CLAUSES (t) = tmp;
12439 stmt = push_stmt_list ();
12440 RECUR (OMP_BODY (t));
12441 stmt = pop_stmt_list (stmt);
12444 OMP_BODY (t) = stmt;
12449 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12451 tree op1 = TREE_OPERAND (t, 1);
12452 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12453 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12454 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12458 case EXPR_PACK_EXPANSION:
12459 error ("invalid use of pack expansion expression");
12460 return error_mark_node;
12462 case NONTYPE_ARGUMENT_PACK:
12463 error ("use %<...%> to expand argument pack");
12464 return error_mark_node;
12467 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12469 return tsubst_copy_and_build (t, args, complain, in_decl,
12470 /*function_p=*/false,
12471 integral_constant_expression_p);
12478 /* T is a postfix-expression that is not being used in a function
12479 call. Return the substituted version of T. */
12482 tsubst_non_call_postfix_expression (tree t, tree args,
12483 tsubst_flags_t complain,
12486 if (TREE_CODE (t) == SCOPE_REF)
12487 t = tsubst_qualified_id (t, args, complain, in_decl,
12488 /*done=*/false, /*address_p=*/false);
12490 t = tsubst_copy_and_build (t, args, complain, in_decl,
12491 /*function_p=*/false,
12492 /*integral_constant_expression_p=*/false);
12497 /* Like tsubst but deals with expressions and performs semantic
12498 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12501 tsubst_copy_and_build (tree t,
12503 tsubst_flags_t complain,
12506 bool integral_constant_expression_p)
12508 #define RECUR(NODE) \
12509 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12510 /*function_p=*/false, \
12511 integral_constant_expression_p)
12515 if (t == NULL_TREE || t == error_mark_node)
12518 switch (TREE_CODE (t))
12522 /* Fall through. */
12523 case IDENTIFIER_NODE:
12527 bool non_integral_constant_expression_p;
12528 const char *error_msg;
12530 if (IDENTIFIER_TYPENAME_P (t))
12532 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12533 t = mangle_conv_op_name_for_type (new_type);
12536 /* Look up the name. */
12537 decl = lookup_name (t);
12539 /* By convention, expressions use ERROR_MARK_NODE to indicate
12540 failure, not NULL_TREE. */
12541 if (decl == NULL_TREE)
12542 decl = error_mark_node;
12544 decl = finish_id_expression (t, decl, NULL_TREE,
12546 integral_constant_expression_p,
12547 /*allow_non_integral_constant_expression_p=*/false,
12548 &non_integral_constant_expression_p,
12549 /*template_p=*/false,
12551 /*address_p=*/false,
12552 /*template_arg_p=*/false,
12557 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12558 decl = unqualified_name_lookup_error (decl);
12562 case TEMPLATE_ID_EXPR:
12565 tree templ = RECUR (TREE_OPERAND (t, 0));
12566 tree targs = TREE_OPERAND (t, 1);
12569 targs = tsubst_template_args (targs, args, complain, in_decl);
12571 if (TREE_CODE (templ) == COMPONENT_REF)
12573 object = TREE_OPERAND (templ, 0);
12574 templ = TREE_OPERAND (templ, 1);
12577 object = NULL_TREE;
12578 templ = lookup_template_function (templ, targs);
12581 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12582 object, templ, NULL_TREE);
12584 return baselink_for_fns (templ);
12589 tree r = RECUR (TREE_OPERAND (t, 0));
12591 if (REFERENCE_REF_P (t))
12593 /* A type conversion to reference type will be enclosed in
12594 such an indirect ref, but the substitution of the cast
12595 will have also added such an indirect ref. */
12596 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12597 r = convert_from_reference (r);
12600 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12606 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12607 RECUR (TREE_OPERAND (t, 0)));
12610 case REINTERPRET_CAST_EXPR:
12611 case CONST_CAST_EXPR:
12612 case DYNAMIC_CAST_EXPR:
12613 case STATIC_CAST_EXPR:
12618 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12619 if (integral_constant_expression_p
12620 && !cast_valid_in_integral_constant_expression_p (type))
12622 if (complain & tf_error)
12623 error ("a cast to a type other than an integral or "
12624 "enumeration type cannot appear in a constant-expression");
12625 return error_mark_node;
12628 op = RECUR (TREE_OPERAND (t, 0));
12630 switch (TREE_CODE (t))
12633 return build_functional_cast (type, op, complain);
12634 case REINTERPRET_CAST_EXPR:
12635 return build_reinterpret_cast (type, op, complain);
12636 case CONST_CAST_EXPR:
12637 return build_const_cast (type, op, complain);
12638 case DYNAMIC_CAST_EXPR:
12639 return build_dynamic_cast (type, op, complain);
12640 case STATIC_CAST_EXPR:
12641 return build_static_cast (type, op, complain);
12643 gcc_unreachable ();
12647 case POSTDECREMENT_EXPR:
12648 case POSTINCREMENT_EXPR:
12649 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12650 args, complain, in_decl);
12651 return build_x_unary_op (TREE_CODE (t), op1, complain);
12653 case PREDECREMENT_EXPR:
12654 case PREINCREMENT_EXPR:
12658 case TRUTH_NOT_EXPR:
12659 case UNARY_PLUS_EXPR: /* Unary + */
12660 case REALPART_EXPR:
12661 case IMAGPART_EXPR:
12662 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12666 op1 = TREE_OPERAND (t, 0);
12667 if (TREE_CODE (op1) == LABEL_DECL)
12668 return finish_label_address_expr (DECL_NAME (op1),
12669 EXPR_LOCATION (op1));
12670 if (TREE_CODE (op1) == SCOPE_REF)
12671 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12672 /*done=*/true, /*address_p=*/true);
12674 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12676 return build_x_unary_op (ADDR_EXPR, op1, complain);
12681 case TRUNC_DIV_EXPR:
12682 case CEIL_DIV_EXPR:
12683 case FLOOR_DIV_EXPR:
12684 case ROUND_DIV_EXPR:
12685 case EXACT_DIV_EXPR:
12689 case TRUNC_MOD_EXPR:
12690 case FLOOR_MOD_EXPR:
12691 case TRUTH_ANDIF_EXPR:
12692 case TRUTH_ORIF_EXPR:
12693 case TRUTH_AND_EXPR:
12694 case TRUTH_OR_EXPR:
12709 return build_x_binary_op
12711 RECUR (TREE_OPERAND (t, 0)),
12712 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12714 : TREE_CODE (TREE_OPERAND (t, 0))),
12715 RECUR (TREE_OPERAND (t, 1)),
12716 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12718 : TREE_CODE (TREE_OPERAND (t, 1))),
12719 /*overloaded_p=*/NULL,
12723 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12724 /*address_p=*/false);
12726 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12727 args, complain, in_decl);
12728 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12731 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12732 return tsubst_copy (t, args, complain, in_decl);
12736 op1 = TREE_OPERAND (t, 0);
12739 /* When there are no ARGS, we are trying to evaluate a
12740 non-dependent expression from the parser. Trying to do
12741 the substitutions may not work. */
12743 op1 = TREE_TYPE (op1);
12747 ++cp_unevaluated_operand;
12748 ++c_inhibit_evaluation_warnings;
12749 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12750 /*function_p=*/false,
12751 /*integral_constant_expression_p=*/false);
12752 --cp_unevaluated_operand;
12753 --c_inhibit_evaluation_warnings;
12756 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12757 complain & tf_error);
12759 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12760 complain & tf_error);
12762 case AT_ENCODE_EXPR:
12764 op1 = TREE_OPERAND (t, 0);
12765 ++cp_unevaluated_operand;
12766 ++c_inhibit_evaluation_warnings;
12767 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12768 /*function_p=*/false,
12769 /*integral_constant_expression_p=*/false);
12770 --cp_unevaluated_operand;
12771 --c_inhibit_evaluation_warnings;
12772 return objc_build_encode_expr (op1);
12775 case NOEXCEPT_EXPR:
12776 op1 = TREE_OPERAND (t, 0);
12777 ++cp_unevaluated_operand;
12778 ++c_inhibit_evaluation_warnings;
12779 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12780 /*function_p=*/false,
12781 /*integral_constant_expression_p=*/false);
12782 --cp_unevaluated_operand;
12783 --c_inhibit_evaluation_warnings;
12784 return finish_noexcept_expr (op1, complain);
12788 tree r = build_x_modify_expr
12789 (RECUR (TREE_OPERAND (t, 0)),
12790 TREE_CODE (TREE_OPERAND (t, 1)),
12791 RECUR (TREE_OPERAND (t, 2)),
12793 /* TREE_NO_WARNING must be set if either the expression was
12794 parenthesized or it uses an operator such as >>= rather
12795 than plain assignment. In the former case, it was already
12796 set and must be copied. In the latter case,
12797 build_x_modify_expr sets it and it must not be reset
12799 if (TREE_NO_WARNING (t))
12800 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12805 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12806 args, complain, in_decl);
12807 /* Remember that there was a reference to this entity. */
12810 return build_x_arrow (op1);
12814 tree placement = RECUR (TREE_OPERAND (t, 0));
12815 tree init = RECUR (TREE_OPERAND (t, 3));
12816 VEC(tree,gc) *placement_vec;
12817 VEC(tree,gc) *init_vec;
12820 if (placement == NULL_TREE)
12821 placement_vec = NULL;
12824 placement_vec = make_tree_vector ();
12825 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12826 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12829 /* If there was an initializer in the original tree, but it
12830 instantiated to an empty list, then we should pass a
12831 non-NULL empty vector to tell build_new that it was an
12832 empty initializer() rather than no initializer. This can
12833 only happen when the initializer is a pack expansion whose
12834 parameter packs are of length zero. */
12835 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12839 init_vec = make_tree_vector ();
12840 if (init == void_zero_node)
12841 gcc_assert (init_vec != NULL);
12844 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12845 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12849 ret = build_new (&placement_vec,
12850 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
12851 RECUR (TREE_OPERAND (t, 2)),
12853 NEW_EXPR_USE_GLOBAL (t),
12856 if (placement_vec != NULL)
12857 release_tree_vector (placement_vec);
12858 if (init_vec != NULL)
12859 release_tree_vector (init_vec);
12865 return delete_sanity
12866 (RECUR (TREE_OPERAND (t, 0)),
12867 RECUR (TREE_OPERAND (t, 1)),
12868 DELETE_EXPR_USE_VEC (t),
12869 DELETE_EXPR_USE_GLOBAL (t),
12872 case COMPOUND_EXPR:
12873 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12874 RECUR (TREE_OPERAND (t, 1)),
12880 VEC(tree,gc) *call_args;
12881 unsigned int nargs, i;
12886 function = CALL_EXPR_FN (t);
12887 /* When we parsed the expression, we determined whether or
12888 not Koenig lookup should be performed. */
12889 koenig_p = KOENIG_LOOKUP_P (t);
12890 if (TREE_CODE (function) == SCOPE_REF)
12892 qualified_p = true;
12893 function = tsubst_qualified_id (function, args, complain, in_decl,
12895 /*address_p=*/false);
12899 if (TREE_CODE (function) == COMPONENT_REF)
12901 tree op = TREE_OPERAND (function, 1);
12903 qualified_p = (TREE_CODE (op) == SCOPE_REF
12904 || (BASELINK_P (op)
12905 && BASELINK_QUALIFIED_P (op)));
12908 qualified_p = false;
12910 function = tsubst_copy_and_build (function, args, complain,
12913 integral_constant_expression_p);
12915 if (BASELINK_P (function))
12916 qualified_p = true;
12919 nargs = call_expr_nargs (t);
12920 call_args = make_tree_vector ();
12921 for (i = 0; i < nargs; ++i)
12923 tree arg = CALL_EXPR_ARG (t, i);
12925 if (!PACK_EXPANSION_P (arg))
12926 VEC_safe_push (tree, gc, call_args,
12927 RECUR (CALL_EXPR_ARG (t, i)));
12930 /* Expand the pack expansion and push each entry onto
12932 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12933 if (TREE_CODE (arg) == TREE_VEC)
12935 unsigned int len, j;
12937 len = TREE_VEC_LENGTH (arg);
12938 for (j = 0; j < len; ++j)
12940 tree value = TREE_VEC_ELT (arg, j);
12941 if (value != NULL_TREE)
12942 value = convert_from_reference (value);
12943 VEC_safe_push (tree, gc, call_args, value);
12948 /* A partial substitution. Add one entry. */
12949 VEC_safe_push (tree, gc, call_args, arg);
12954 /* We do not perform argument-dependent lookup if normal
12955 lookup finds a non-function, in accordance with the
12956 expected resolution of DR 218. */
12958 && ((is_overloaded_fn (function)
12959 /* If lookup found a member function, the Koenig lookup is
12960 not appropriate, even if an unqualified-name was used
12961 to denote the function. */
12962 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12963 || TREE_CODE (function) == IDENTIFIER_NODE)
12964 /* Only do this when substitution turns a dependent call
12965 into a non-dependent call. */
12966 && type_dependent_expression_p_push (t)
12967 && !any_type_dependent_arguments_p (call_args))
12968 function = perform_koenig_lookup (function, call_args, false);
12970 if (TREE_CODE (function) == IDENTIFIER_NODE
12971 && !processing_template_decl)
12973 unqualified_name_lookup_error (function);
12974 release_tree_vector (call_args);
12975 return error_mark_node;
12978 /* Remember that there was a reference to this entity. */
12979 if (DECL_P (function))
12980 mark_used (function);
12982 if (TREE_CODE (function) == OFFSET_REF)
12983 ret = build_offset_ref_call_from_tree (function, &call_args);
12984 else if (TREE_CODE (function) == COMPONENT_REF)
12986 tree instance = TREE_OPERAND (function, 0);
12987 tree fn = TREE_OPERAND (function, 1);
12989 if (processing_template_decl
12990 && (type_dependent_expression_p (instance)
12991 || (!BASELINK_P (fn)
12992 && TREE_CODE (fn) != FIELD_DECL)
12993 || type_dependent_expression_p (fn)
12994 || any_type_dependent_arguments_p (call_args)))
12995 ret = build_nt_call_vec (function, call_args);
12996 else if (!BASELINK_P (fn))
12997 ret = finish_call_expr (function, &call_args,
12998 /*disallow_virtual=*/false,
12999 /*koenig_p=*/false,
13002 ret = (build_new_method_call
13004 &call_args, NULL_TREE,
13005 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13010 ret = finish_call_expr (function, &call_args,
13011 /*disallow_virtual=*/qualified_p,
13015 release_tree_vector (call_args);
13021 return build_x_conditional_expr
13022 (RECUR (TREE_OPERAND (t, 0)),
13023 RECUR (TREE_OPERAND (t, 1)),
13024 RECUR (TREE_OPERAND (t, 2)),
13027 case PSEUDO_DTOR_EXPR:
13028 return finish_pseudo_destructor_expr
13029 (RECUR (TREE_OPERAND (t, 0)),
13030 RECUR (TREE_OPERAND (t, 1)),
13031 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13035 tree purpose, value, chain;
13037 if (t == void_list_node)
13040 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13041 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13043 /* We have pack expansions, so expand those and
13044 create a new list out of it. */
13045 tree purposevec = NULL_TREE;
13046 tree valuevec = NULL_TREE;
13050 /* Expand the argument expressions. */
13051 if (TREE_PURPOSE (t))
13052 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13053 complain, in_decl);
13054 if (TREE_VALUE (t))
13055 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13056 complain, in_decl);
13058 /* Build the rest of the list. */
13059 chain = TREE_CHAIN (t);
13060 if (chain && chain != void_type_node)
13061 chain = RECUR (chain);
13063 /* Determine the number of arguments. */
13064 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13066 len = TREE_VEC_LENGTH (purposevec);
13067 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13069 else if (TREE_CODE (valuevec) == TREE_VEC)
13070 len = TREE_VEC_LENGTH (valuevec);
13073 /* Since we only performed a partial substitution into
13074 the argument pack, we only return a single list
13076 if (purposevec == TREE_PURPOSE (t)
13077 && valuevec == TREE_VALUE (t)
13078 && chain == TREE_CHAIN (t))
13081 return tree_cons (purposevec, valuevec, chain);
13084 /* Convert the argument vectors into a TREE_LIST */
13088 /* Grab the Ith values. */
13090 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13093 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13096 /* Build the list (backwards). */
13097 chain = tree_cons (purpose, value, chain);
13103 purpose = TREE_PURPOSE (t);
13105 purpose = RECUR (purpose);
13106 value = TREE_VALUE (t);
13108 value = RECUR (value);
13109 chain = TREE_CHAIN (t);
13110 if (chain && chain != void_type_node)
13111 chain = RECUR (chain);
13112 if (purpose == TREE_PURPOSE (t)
13113 && value == TREE_VALUE (t)
13114 && chain == TREE_CHAIN (t))
13116 return tree_cons (purpose, value, chain);
13119 case COMPONENT_REF:
13125 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13126 args, complain, in_decl);
13127 /* Remember that there was a reference to this entity. */
13128 if (DECL_P (object))
13129 mark_used (object);
13130 object_type = TREE_TYPE (object);
13132 member = TREE_OPERAND (t, 1);
13133 if (BASELINK_P (member))
13134 member = tsubst_baselink (member,
13135 non_reference (TREE_TYPE (object)),
13136 args, complain, in_decl);
13138 member = tsubst_copy (member, args, complain, in_decl);
13139 if (member == error_mark_node)
13140 return error_mark_node;
13142 if (object_type && !CLASS_TYPE_P (object_type))
13144 if (SCALAR_TYPE_P (object_type))
13146 tree s = NULL_TREE;
13147 tree dtor = member;
13149 if (TREE_CODE (dtor) == SCOPE_REF)
13151 s = TREE_OPERAND (dtor, 0);
13152 dtor = TREE_OPERAND (dtor, 1);
13154 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13156 dtor = TREE_OPERAND (dtor, 0);
13158 return finish_pseudo_destructor_expr (object, s, dtor);
13162 else if (TREE_CODE (member) == SCOPE_REF
13163 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13168 /* Lookup the template functions now that we know what the
13170 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13171 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13172 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13173 /*is_type_p=*/false,
13174 /*complain=*/false);
13175 if (BASELINK_P (member))
13177 BASELINK_FUNCTIONS (member)
13178 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13180 member = (adjust_result_of_qualified_name_lookup
13181 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13186 qualified_name_lookup_error (object_type, tmpl, member,
13188 return error_mark_node;
13191 else if (TREE_CODE (member) == SCOPE_REF
13192 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13193 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13195 if (complain & tf_error)
13197 if (TYPE_P (TREE_OPERAND (member, 0)))
13198 error ("%qT is not a class or namespace",
13199 TREE_OPERAND (member, 0));
13201 error ("%qD is not a class or namespace",
13202 TREE_OPERAND (member, 0));
13204 return error_mark_node;
13206 else if (TREE_CODE (member) == FIELD_DECL)
13207 return finish_non_static_data_member (member, object, NULL_TREE);
13209 return finish_class_member_access_expr (object, member,
13210 /*template_p=*/false,
13216 (RECUR (TREE_OPERAND (t, 0)));
13220 VEC(constructor_elt,gc) *n;
13221 constructor_elt *ce;
13222 unsigned HOST_WIDE_INT idx;
13223 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13224 bool process_index_p;
13226 bool need_copy_p = false;
13229 if (type == error_mark_node)
13230 return error_mark_node;
13232 /* digest_init will do the wrong thing if we let it. */
13233 if (type && TYPE_PTRMEMFUNC_P (type))
13236 /* We do not want to process the index of aggregate
13237 initializers as they are identifier nodes which will be
13238 looked up by digest_init. */
13239 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13241 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13242 newlen = VEC_length (constructor_elt, n);
13243 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13245 if (ce->index && process_index_p)
13246 ce->index = RECUR (ce->index);
13248 if (PACK_EXPANSION_P (ce->value))
13250 /* Substitute into the pack expansion. */
13251 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13254 if (ce->value == error_mark_node
13255 || PACK_EXPANSION_P (ce->value))
13257 else if (TREE_VEC_LENGTH (ce->value) == 1)
13258 /* Just move the argument into place. */
13259 ce->value = TREE_VEC_ELT (ce->value, 0);
13262 /* Update the length of the final CONSTRUCTOR
13263 arguments vector, and note that we will need to
13265 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13266 need_copy_p = true;
13270 ce->value = RECUR (ce->value);
13275 VEC(constructor_elt,gc) *old_n = n;
13277 n = VEC_alloc (constructor_elt, gc, newlen);
13278 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13280 if (TREE_CODE (ce->value) == TREE_VEC)
13282 int i, len = TREE_VEC_LENGTH (ce->value);
13283 for (i = 0; i < len; ++i)
13284 CONSTRUCTOR_APPEND_ELT (n, 0,
13285 TREE_VEC_ELT (ce->value, i));
13288 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13292 r = build_constructor (init_list_type_node, n);
13293 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13295 if (TREE_HAS_CONSTRUCTOR (t))
13296 return finish_compound_literal (type, r, complain);
13298 TREE_TYPE (r) = type;
13304 tree operand_0 = TREE_OPERAND (t, 0);
13305 if (TYPE_P (operand_0))
13307 operand_0 = tsubst (operand_0, args, complain, in_decl);
13308 return get_typeid (operand_0);
13312 operand_0 = RECUR (operand_0);
13313 return build_typeid (operand_0);
13324 tree r = tsubst_copy (t, args, complain, in_decl);
13326 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13327 /* If the original type was a reference, we'll be wrapped in
13328 the appropriate INDIRECT_REF. */
13329 r = convert_from_reference (r);
13334 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13335 tsubst (TREE_TYPE (t), args, complain, in_decl));
13337 case OFFSETOF_EXPR:
13338 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13342 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13343 complain, in_decl);
13345 tree type2 = TRAIT_EXPR_TYPE2 (t);
13347 type2 = tsubst_copy (type2, args, complain, in_decl);
13349 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13354 tree old_stmt_expr = cur_stmt_expr;
13355 tree stmt_expr = begin_stmt_expr ();
13357 cur_stmt_expr = stmt_expr;
13358 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13359 integral_constant_expression_p);
13360 stmt_expr = finish_stmt_expr (stmt_expr, false);
13361 cur_stmt_expr = old_stmt_expr;
13363 /* If the resulting list of expression statement is empty,
13364 fold it further into void_zero_node. */
13365 if (empty_expr_stmt_p (stmt_expr))
13366 stmt_expr = void_zero_node;
13372 t = tsubst_copy (t, args, complain, in_decl);
13373 /* As in finish_id_expression, we resolve enumeration constants
13374 to their underlying values. */
13375 if (TREE_CODE (t) == CONST_DECL)
13377 used_types_insert (TREE_TYPE (t));
13378 return DECL_INITIAL (t);
13384 tree r = build_lambda_expr ();
13386 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13387 TREE_TYPE (r) = type;
13388 CLASSTYPE_LAMBDA_EXPR (type) = r;
13390 LAMBDA_EXPR_LOCATION (r)
13391 = LAMBDA_EXPR_LOCATION (t);
13392 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13393 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13394 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13395 LAMBDA_EXPR_DISCRIMINATOR (r)
13396 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13397 LAMBDA_EXPR_CAPTURE_LIST (r)
13398 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13399 LAMBDA_EXPR_THIS_CAPTURE (r)
13400 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
13401 LAMBDA_EXPR_EXTRA_SCOPE (r)
13402 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13404 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13405 determine_visibility (TYPE_NAME (type));
13406 /* Now that we know visibility, instantiate the type so we have a
13407 declaration of the op() for later calls to lambda_function. */
13408 complete_type (type);
13410 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13412 apply_lambda_return_type (r, type);
13414 return build_lambda_object (r);
13418 /* We can get here for a constant initializer of non-dependent type.
13419 FIXME stop folding in cp_parser_initializer_clause. */
13420 gcc_assert (TREE_CONSTANT (t));
13422 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
13423 TREE_CONSTANT (r) = true;
13428 /* Handle Objective-C++ constructs, if appropriate. */
13431 = objcp_tsubst_copy_and_build (t, args, complain,
13432 in_decl, /*function_p=*/false);
13436 return tsubst_copy (t, args, complain, in_decl);
13442 /* Verify that the instantiated ARGS are valid. For type arguments,
13443 make sure that the type's linkage is ok. For non-type arguments,
13444 make sure they are constants if they are integral or enumerations.
13445 Emit an error under control of COMPLAIN, and return TRUE on error. */
13448 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13450 if (ARGUMENT_PACK_P (t))
13452 tree vec = ARGUMENT_PACK_ARGS (t);
13453 int len = TREE_VEC_LENGTH (vec);
13454 bool result = false;
13457 for (i = 0; i < len; ++i)
13458 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13462 else if (TYPE_P (t))
13464 /* [basic.link]: A name with no linkage (notably, the name
13465 of a class or enumeration declared in a local scope)
13466 shall not be used to declare an entity with linkage.
13467 This implies that names with no linkage cannot be used as
13470 DR 757 relaxes this restriction for C++0x. */
13471 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13472 : no_linkage_check (t, /*relaxed_p=*/false));
13476 /* DR 488 makes use of a type with no linkage cause
13477 type deduction to fail. */
13478 if (complain & tf_error)
13480 if (TYPE_ANONYMOUS_P (nt))
13481 error ("%qT is/uses anonymous type", t);
13483 error ("template argument for %qD uses local type %qT",
13488 /* In order to avoid all sorts of complications, we do not
13489 allow variably-modified types as template arguments. */
13490 else if (variably_modified_type_p (t, NULL_TREE))
13492 if (complain & tf_error)
13493 error ("%qT is a variably modified type", t);
13497 /* A non-type argument of integral or enumerated type must be a
13499 else if (TREE_TYPE (t)
13500 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13501 && !TREE_CONSTANT (t))
13503 if (complain & tf_error)
13504 error ("integral expression %qE is not constant", t);
13511 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13513 int ix, len = DECL_NTPARMS (tmpl);
13514 bool result = false;
13516 for (ix = 0; ix != len; ix++)
13518 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13521 if (result && (complain & tf_error))
13522 error (" trying to instantiate %qD", tmpl);
13526 DEF_VEC_O (spec_entry);
13527 DEF_VEC_ALLOC_O (spec_entry,gc);
13528 static GTY(()) VEC(spec_entry,gc) *current_deduction_vec;
13529 static GTY((param_is (spec_entry))) htab_t current_deduction_htab;
13531 /* In C++0x, it's possible to have a function template whose type depends
13532 on itself recursively. This is most obvious with decltype, but can also
13533 occur with enumeration scope (c++/48969). So we need to catch infinite
13534 recursion and reject the substitution at deduction time.
13536 Use of a VEC here is O(n^2) in the depth of function template argument
13537 deduction substitution, but using a hash table creates a lot of constant
13538 overhead for the typical case of very low depth. So to make the typical
13539 case fast we start out with a VEC and switch to a hash table only if
13540 depth gets to be significant; in one metaprogramming testcase, even at
13541 depth 80 the overhead of the VEC relative to a hash table was only about
13542 0.5% of compile time. */
13545 deduction_tsubst_fntype (tree fn, tree targs)
13554 tree fntype = TREE_TYPE (fn);
13556 /* We don't need to worry about this in C++98. */
13557 if (cxx_dialect < cxx0x)
13558 return tsubst (fntype, targs, tf_none, NULL_TREE);
13560 /* If we're seeing a lot of recursion, switch over to a hash table. The
13561 constant 40 is fairly arbitrary. */
13562 if (!current_deduction_htab
13563 && VEC_length (spec_entry, current_deduction_vec) > 40)
13565 current_deduction_htab = htab_create_ggc (40*2, hash_specialization,
13566 eq_specializations, ggc_free);
13567 FOR_EACH_VEC_ELT (spec_entry, current_deduction_vec, i, p)
13569 slot = (spec_entry **) htab_find_slot (current_deduction_htab,
13571 *slot = ggc_alloc_spec_entry ();
13574 VEC_free (spec_entry, gc, current_deduction_vec);
13577 /* Now check everything in the vector, if any. */
13578 FOR_EACH_VEC_ELT (spec_entry, current_deduction_vec, i, p)
13579 if (p->tmpl == fn && comp_template_args (p->args, targs))
13581 p->spec = error_mark_node;
13582 return error_mark_node;
13587 elt.spec = NULL_TREE;
13589 /* If we've created a hash table, look there. */
13590 if (current_deduction_htab)
13592 hash = hash_specialization (&elt);
13593 slot = (spec_entry **)
13594 htab_find_slot_with_hash (current_deduction_htab, &elt, hash, INSERT);
13597 /* We already have an entry for this. */
13598 (*slot)->spec = error_mark_node;
13599 return error_mark_node;
13603 /* Create a new entry. */
13604 *slot = ggc_alloc_spec_entry ();
13610 /* No hash table, so add it to the VEC. */
13612 VEC_safe_push (spec_entry, gc, current_deduction_vec, &elt);
13615 r = tsubst (fntype, targs, tf_none, NULL_TREE);
13617 /* After doing the substitution, make sure we didn't hit it again. Note
13618 that we might have switched to a hash table during tsubst. */
13619 if (current_deduction_htab)
13622 hash = hash_specialization (&elt);
13623 slot = (spec_entry **)
13624 htab_find_slot_with_hash (current_deduction_htab, &elt, hash,
13626 if ((*slot)->spec == error_mark_node)
13627 r = error_mark_node;
13628 htab_clear_slot (current_deduction_htab, (void**)slot);
13632 if (VEC_last (spec_entry, current_deduction_vec)->spec
13633 == error_mark_node)
13634 r = error_mark_node;
13635 VEC_pop (spec_entry, current_deduction_vec);
13640 /* Instantiate the indicated variable or function template TMPL with
13641 the template arguments in TARG_PTR. */
13644 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
13646 tree targ_ptr = orig_args;
13650 HOST_WIDE_INT saved_processing_template_decl;
13652 if (tmpl == error_mark_node)
13653 return error_mark_node;
13655 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13657 /* If this function is a clone, handle it specially. */
13658 if (DECL_CLONED_FUNCTION_P (tmpl))
13663 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13664 DECL_CLONED_FUNCTION. */
13665 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13666 targ_ptr, complain);
13667 if (spec == error_mark_node)
13668 return error_mark_node;
13670 /* Look for the clone. */
13671 FOR_EACH_CLONE (clone, spec)
13672 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13674 /* We should always have found the clone by now. */
13675 gcc_unreachable ();
13679 /* Check to see if we already have this specialization. */
13680 gen_tmpl = most_general_template (tmpl);
13681 if (tmpl != gen_tmpl)
13682 /* The TMPL is a partial instantiation. To get a full set of
13683 arguments we must add the arguments used to perform the
13684 partial instantiation. */
13685 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13688 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13689 but it doesn't seem to be on the hot path. */
13690 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13692 gcc_assert (tmpl == gen_tmpl
13693 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13695 || fndecl == NULL_TREE);
13697 if (spec != NULL_TREE)
13700 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13702 return error_mark_node;
13704 /* We are building a FUNCTION_DECL, during which the access of its
13705 parameters and return types have to be checked. However this
13706 FUNCTION_DECL which is the desired context for access checking
13707 is not built yet. We solve this chicken-and-egg problem by
13708 deferring all checks until we have the FUNCTION_DECL. */
13709 push_deferring_access_checks (dk_deferred);
13711 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13712 (because, for example, we have encountered a non-dependent
13713 function call in the body of a template function and must now
13714 determine which of several overloaded functions will be called),
13715 within the instantiation itself we are not processing a
13717 saved_processing_template_decl = processing_template_decl;
13718 processing_template_decl = 0;
13719 /* Substitute template parameters to obtain the specialization. */
13720 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13721 targ_ptr, complain, gen_tmpl);
13722 processing_template_decl = saved_processing_template_decl;
13723 if (fndecl == error_mark_node)
13724 return error_mark_node;
13726 /* Now we know the specialization, compute access previously
13728 push_access_scope (fndecl);
13730 /* Some typedefs referenced from within the template code need to be access
13731 checked at template instantiation time, i.e now. These types were
13732 added to the template at parsing time. Let's get those and perfom
13733 the acces checks then. */
13734 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13735 perform_deferred_access_checks ();
13736 pop_access_scope (fndecl);
13737 pop_deferring_access_checks ();
13739 /* The DECL_TI_TEMPLATE should always be the immediate parent
13740 template, not the most general template. */
13741 DECL_TI_TEMPLATE (fndecl) = tmpl;
13743 /* If we've just instantiated the main entry point for a function,
13744 instantiate all the alternate entry points as well. We do this
13745 by cloning the instantiation of the main entry point, not by
13746 instantiating the template clones. */
13747 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13748 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13753 /* Wrapper for instantiate_template_1. */
13756 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13759 timevar_push (TV_TEMPLATE_INST);
13760 ret = instantiate_template_1 (tmpl, orig_args, complain);
13761 timevar_pop (TV_TEMPLATE_INST);
13765 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13766 NARGS elements of the arguments that are being used when calling
13767 it. TARGS is a vector into which the deduced template arguments
13770 Return zero for success, 2 for an incomplete match that doesn't resolve
13771 all the types, and 1 for complete failure. An error message will be
13772 printed only for an incomplete match.
13774 If FN is a conversion operator, or we are trying to produce a specific
13775 specialization, RETURN_TYPE is the return type desired.
13777 The EXPLICIT_TARGS are explicit template arguments provided via a
13780 The parameter STRICT is one of:
13783 We are deducing arguments for a function call, as in
13784 [temp.deduct.call].
13787 We are deducing arguments for a conversion function, as in
13788 [temp.deduct.conv].
13791 We are deducing arguments when doing an explicit instantiation
13792 as in [temp.explicit], when determining an explicit specialization
13793 as in [temp.expl.spec], or when taking the address of a function
13794 template, as in [temp.deduct.funcaddr]. */
13797 fn_type_unification (tree fn,
13798 tree explicit_targs,
13801 unsigned int nargs,
13803 unification_kind_t strict,
13809 bool incomplete_argument_packs_p = false;
13811 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13813 fntype = TREE_TYPE (fn);
13814 if (explicit_targs)
13818 The specified template arguments must match the template
13819 parameters in kind (i.e., type, nontype, template), and there
13820 must not be more arguments than there are parameters;
13821 otherwise type deduction fails.
13823 Nontype arguments must match the types of the corresponding
13824 nontype template parameters, or must be convertible to the
13825 types of the corresponding nontype parameters as specified in
13826 _temp.arg.nontype_, otherwise type deduction fails.
13828 All references in the function type of the function template
13829 to the corresponding template parameters are replaced by the
13830 specified template argument values. If a substitution in a
13831 template parameter or in the function type of the function
13832 template results in an invalid type, type deduction fails. */
13833 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13834 int i, len = TREE_VEC_LENGTH (tparms);
13835 tree converted_args;
13836 bool incomplete = false;
13838 if (explicit_targs == error_mark_node)
13842 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13843 /*require_all_args=*/false,
13844 /*use_default_args=*/false));
13845 if (converted_args == error_mark_node)
13848 /* Substitute the explicit args into the function type. This is
13849 necessary so that, for instance, explicitly declared function
13850 arguments can match null pointed constants. If we were given
13851 an incomplete set of explicit args, we must not do semantic
13852 processing during substitution as we could create partial
13854 for (i = 0; i < len; i++)
13856 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13857 bool parameter_pack = false;
13859 /* Dig out the actual parm. */
13860 if (TREE_CODE (parm) == TYPE_DECL
13861 || TREE_CODE (parm) == TEMPLATE_DECL)
13863 parm = TREE_TYPE (parm);
13864 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13866 else if (TREE_CODE (parm) == PARM_DECL)
13868 parm = DECL_INITIAL (parm);
13869 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13872 if (parameter_pack)
13876 template_parm_level_and_index (parm, &level, &idx);
13878 /* Mark the argument pack as "incomplete". We could
13879 still deduce more arguments during unification.
13880 We remove this mark in type_unification_real. */
13881 targ = TMPL_ARG (converted_args, level, idx);
13884 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13885 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13886 = ARGUMENT_PACK_ARGS (targ);
13889 /* We have some incomplete argument packs. */
13890 incomplete_argument_packs_p = true;
13894 if (incomplete_argument_packs_p)
13895 /* Any substitution is guaranteed to be incomplete if there
13896 are incomplete argument packs, because we can still deduce
13900 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13902 processing_template_decl += incomplete;
13903 fntype = deduction_tsubst_fntype (fn, converted_args);
13904 processing_template_decl -= incomplete;
13906 if (fntype == error_mark_node)
13909 /* Place the explicitly specified arguments in TARGS. */
13910 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13911 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13914 /* Never do unification on the 'this' parameter. */
13915 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13921 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13922 new_args = XALLOCAVEC (tree, nargs + 1);
13923 new_args[0] = return_type;
13924 memcpy (new_args + 1, args, nargs * sizeof (tree));
13929 /* We allow incomplete unification without an error message here
13930 because the standard doesn't seem to explicitly prohibit it. Our
13931 callers must be ready to deal with unification failures in any
13933 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13934 targs, parms, args, nargs, /*subr=*/0,
13937 /* Now that we have bindings for all of the template arguments,
13938 ensure that the arguments deduced for the template template
13939 parameters have compatible template parameter lists. We cannot
13940 check this property before we have deduced all template
13941 arguments, because the template parameter types of a template
13942 template parameter might depend on prior template parameters
13943 deduced after the template template parameter. The following
13944 ill-formed example illustrates this issue:
13946 template<typename T, template<T> class C> void f(C<5>, T);
13948 template<int N> struct X {};
13951 f(X<5>(), 5l); // error: template argument deduction fails
13954 The template parameter list of 'C' depends on the template type
13955 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13956 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13957 time that we deduce 'C'. */
13959 && !template_template_parm_bindings_ok_p
13960 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
13964 /* All is well so far. Now, check:
13968 When all template arguments have been deduced, all uses of
13969 template parameters in nondeduced contexts are replaced with
13970 the corresponding deduced argument values. If the
13971 substitution results in an invalid type, as described above,
13972 type deduction fails. */
13974 tree substed = deduction_tsubst_fntype (fn, targs);
13975 if (substed == error_mark_node)
13978 /* If we're looking for an exact match, check that what we got
13979 is indeed an exact match. It might not be if some template
13980 parameters are used in non-deduced contexts. */
13981 if (strict == DEDUCE_EXACT)
13986 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
13988 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
13989 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
13990 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13998 /* Adjust types before performing type deduction, as described in
13999 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14000 sections are symmetric. PARM is the type of a function parameter
14001 or the return type of the conversion function. ARG is the type of
14002 the argument passed to the call, or the type of the value
14003 initialized with the result of the conversion function.
14004 ARG_EXPR is the original argument expression, which may be null. */
14007 maybe_adjust_types_for_deduction (unification_kind_t strict,
14021 /* Swap PARM and ARG throughout the remainder of this
14022 function; the handling is precisely symmetric since PARM
14023 will initialize ARG rather than vice versa. */
14031 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14032 too, but here handle it by stripping the reference from PARM
14033 rather than by adding it to ARG. */
14034 if (TREE_CODE (*parm) == REFERENCE_TYPE
14035 && TYPE_REF_IS_RVALUE (*parm)
14036 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14037 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14038 && TREE_CODE (*arg) == REFERENCE_TYPE
14039 && !TYPE_REF_IS_RVALUE (*arg))
14040 *parm = TREE_TYPE (*parm);
14041 /* Nothing else to do in this case. */
14045 gcc_unreachable ();
14048 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14050 /* [temp.deduct.call]
14052 If P is not a reference type:
14054 --If A is an array type, the pointer type produced by the
14055 array-to-pointer standard conversion (_conv.array_) is
14056 used in place of A for type deduction; otherwise,
14058 --If A is a function type, the pointer type produced by
14059 the function-to-pointer standard conversion
14060 (_conv.func_) is used in place of A for type deduction;
14063 --If A is a cv-qualified type, the top level
14064 cv-qualifiers of A's type are ignored for type
14066 if (TREE_CODE (*arg) == ARRAY_TYPE)
14067 *arg = build_pointer_type (TREE_TYPE (*arg));
14068 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14069 *arg = build_pointer_type (*arg);
14071 *arg = TYPE_MAIN_VARIANT (*arg);
14074 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14075 of the form T&&, where T is a template parameter, and the argument
14076 is an lvalue, T is deduced as A& */
14077 if (TREE_CODE (*parm) == REFERENCE_TYPE
14078 && TYPE_REF_IS_RVALUE (*parm)
14079 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14080 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14081 && (arg_expr ? real_lvalue_p (arg_expr)
14082 /* try_one_overload doesn't provide an arg_expr, but
14083 functions are always lvalues. */
14084 : TREE_CODE (*arg) == FUNCTION_TYPE))
14085 *arg = build_reference_type (*arg);
14087 /* [temp.deduct.call]
14089 If P is a cv-qualified type, the top level cv-qualifiers
14090 of P's type are ignored for type deduction. If P is a
14091 reference type, the type referred to by P is used for
14093 *parm = TYPE_MAIN_VARIANT (*parm);
14094 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14096 *parm = TREE_TYPE (*parm);
14097 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14100 /* DR 322. For conversion deduction, remove a reference type on parm
14101 too (which has been swapped into ARG). */
14102 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14103 *arg = TREE_TYPE (*arg);
14108 /* Most parms like fn_type_unification.
14110 If SUBR is 1, we're being called recursively (to unify the
14111 arguments of a function or method parameter of a function
14115 type_unification_real (tree tparms,
14119 unsigned int xnargs,
14121 unification_kind_t strict,
14124 tree parm, arg, arg_expr;
14126 int ntparms = TREE_VEC_LENGTH (tparms);
14128 int saw_undeduced = 0;
14131 unsigned int nargs;
14134 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14135 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14136 gcc_assert (ntparms > 0);
14138 /* Reset the number of non-defaulted template arguments contained
14140 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14145 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
14146 | UNIFY_ALLOW_DERIVED);
14150 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14154 sub_strict = UNIFY_ALLOW_NONE;
14158 gcc_unreachable ();
14167 while (parms && parms != void_list_node
14170 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14173 parm = TREE_VALUE (parms);
14174 parms = TREE_CHAIN (parms);
14179 if (arg == error_mark_node)
14181 if (arg == unknown_type_node)
14182 /* We can't deduce anything from this, but we might get all the
14183 template args from other function args. */
14186 /* Conversions will be performed on a function argument that
14187 corresponds with a function parameter that contains only
14188 non-deducible template parameters and explicitly specified
14189 template parameters. */
14190 if (!uses_template_parms (parm))
14195 type = TREE_TYPE (arg);
14199 if (same_type_p (parm, type))
14201 if (strict != DEDUCE_EXACT
14202 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
14211 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14212 if (type_unknown_p (arg))
14214 /* [temp.deduct.type]
14216 A template-argument can be deduced from a pointer to
14217 function or pointer to member function argument if
14218 the set of overloaded functions does not contain
14219 function templates and at most one of a set of
14220 overloaded functions provides a unique match. */
14221 if (resolve_overloaded_unification
14222 (tparms, targs, parm, arg, strict, sub_strict))
14228 arg = unlowered_expr_type (arg);
14229 if (arg == error_mark_node)
14234 int arg_strict = sub_strict;
14237 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14240 if (arg == init_list_type_node && arg_expr)
14242 if (unify (tparms, targs, parm, arg, arg_strict))
14249 && parms != void_list_node
14250 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14252 /* Unify the remaining arguments with the pack expansion type. */
14254 tree parmvec = make_tree_vec (1);
14256 /* Allocate a TREE_VEC and copy in all of the arguments */
14257 argvec = make_tree_vec (nargs - ia);
14258 for (i = 0; ia < nargs; ++ia, ++i)
14259 TREE_VEC_ELT (argvec, i) = args[ia];
14261 /* Copy the parameter into parmvec. */
14262 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14263 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14264 /*call_args_p=*/true, /*subr=*/subr))
14267 /* Advance to the end of the list of parameters. */
14268 parms = TREE_CHAIN (parms);
14271 /* Fail if we've reached the end of the parm list, and more args
14272 are present, and the parm list isn't variadic. */
14273 if (ia < nargs && parms == void_list_node)
14275 /* Fail if parms are left and they don't have default values. */
14276 if (parms && parms != void_list_node
14277 && TREE_PURPOSE (parms) == NULL_TREE)
14282 /* Check to see if we need another pass before we start clearing
14283 ARGUMENT_PACK_INCOMPLETE_P. */
14284 for (i = 0; i < ntparms; i++)
14286 tree targ = TREE_VEC_ELT (targs, i);
14287 tree tparm = TREE_VEC_ELT (tparms, i);
14289 if (targ || tparm == error_mark_node)
14291 tparm = TREE_VALUE (tparm);
14293 /* If this is an undeduced nontype parameter that depends on
14294 a type parameter, try another pass; its type may have been
14295 deduced from a later argument than the one from which
14296 this parameter can be deduced. */
14297 if (TREE_CODE (tparm) == PARM_DECL
14298 && uses_template_parms (TREE_TYPE (tparm))
14299 && !saw_undeduced++)
14303 for (i = 0; i < ntparms; i++)
14305 tree targ = TREE_VEC_ELT (targs, i);
14306 tree tparm = TREE_VEC_ELT (tparms, i);
14308 /* Clear the "incomplete" flags on all argument packs now so that
14309 substituting them into later default arguments works. */
14310 if (targ && ARGUMENT_PACK_P (targ))
14312 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14313 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14316 if (targ || tparm == error_mark_node)
14318 tparm = TREE_VALUE (tparm);
14320 /* Core issue #226 (C++0x) [temp.deduct]:
14322 If a template argument has not been deduced, its
14323 default template argument, if any, is used.
14325 When we are in C++98 mode, TREE_PURPOSE will either
14326 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14327 to explicitly check cxx_dialect here. */
14328 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14330 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14331 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14332 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14333 arg = convert_template_argument (parm, arg, targs, tf_none,
14335 if (arg == error_mark_node)
14339 TREE_VEC_ELT (targs, i) = arg;
14340 /* The position of the first default template argument,
14341 is also the number of non-defaulted arguments in TARGS.
14343 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14344 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14349 /* If the type parameter is a parameter pack, then it will
14350 be deduced to an empty parameter pack. */
14351 if (template_parameter_pack_p (tparm))
14355 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14357 arg = make_node (NONTYPE_ARGUMENT_PACK);
14358 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14359 TREE_CONSTANT (arg) = 1;
14362 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14364 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14366 TREE_VEC_ELT (targs, i) = arg;
14373 #ifdef ENABLE_CHECKING
14374 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14375 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14381 /* Subroutine of type_unification_real. Args are like the variables
14382 at the call site. ARG is an overloaded function (or template-id);
14383 we try deducing template args from each of the overloads, and if
14384 only one succeeds, we go with that. Modifies TARGS and returns
14385 true on success. */
14388 resolve_overloaded_unification (tree tparms,
14392 unification_kind_t strict,
14395 tree tempargs = copy_node (targs);
14397 tree goodfn = NULL_TREE;
14400 if (TREE_CODE (arg) == ADDR_EXPR)
14402 arg = TREE_OPERAND (arg, 0);
14408 if (TREE_CODE (arg) == COMPONENT_REF)
14409 /* Handle `&x' where `x' is some static or non-static member
14411 arg = TREE_OPERAND (arg, 1);
14413 if (TREE_CODE (arg) == OFFSET_REF)
14414 arg = TREE_OPERAND (arg, 1);
14416 /* Strip baselink information. */
14417 if (BASELINK_P (arg))
14418 arg = BASELINK_FUNCTIONS (arg);
14420 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14422 /* If we got some explicit template args, we need to plug them into
14423 the affected templates before we try to unify, in case the
14424 explicit args will completely resolve the templates in question. */
14426 tree expl_subargs = TREE_OPERAND (arg, 1);
14427 arg = TREE_OPERAND (arg, 0);
14429 for (; arg; arg = OVL_NEXT (arg))
14431 tree fn = OVL_CURRENT (arg);
14432 tree subargs, elem;
14434 if (TREE_CODE (fn) != TEMPLATE_DECL)
14437 ++processing_template_decl;
14438 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14439 expl_subargs, /*check_ret=*/false);
14442 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14443 if (try_one_overload (tparms, targs, tempargs, parm,
14444 elem, strict, sub_strict, addr_p)
14445 && (!goodfn || !decls_match (goodfn, elem)))
14451 --processing_template_decl;
14454 else if (TREE_CODE (arg) != OVERLOAD
14455 && TREE_CODE (arg) != FUNCTION_DECL)
14456 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14457 -- but the deduction does not succeed because the expression is
14458 not just the function on its own. */
14461 for (; arg; arg = OVL_NEXT (arg))
14462 if (try_one_overload (tparms, targs, tempargs, parm,
14463 TREE_TYPE (OVL_CURRENT (arg)),
14464 strict, sub_strict, addr_p)
14465 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
14467 goodfn = OVL_CURRENT (arg);
14471 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14472 to function or pointer to member function argument if the set of
14473 overloaded functions does not contain function templates and at most
14474 one of a set of overloaded functions provides a unique match.
14476 So if we found multiple possibilities, we return success but don't
14477 deduce anything. */
14481 int i = TREE_VEC_LENGTH (targs);
14483 if (TREE_VEC_ELT (tempargs, i))
14484 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
14492 /* Core DR 115: In contexts where deduction is done and fails, or in
14493 contexts where deduction is not done, if a template argument list is
14494 specified and it, along with any default template arguments, identifies
14495 a single function template specialization, then the template-id is an
14496 lvalue for the function template specialization. */
14499 resolve_nondeduced_context (tree orig_expr)
14501 tree expr, offset, baselink;
14504 if (!type_unknown_p (orig_expr))
14509 offset = NULL_TREE;
14510 baselink = NULL_TREE;
14512 if (TREE_CODE (expr) == ADDR_EXPR)
14514 expr = TREE_OPERAND (expr, 0);
14517 if (TREE_CODE (expr) == OFFSET_REF)
14520 expr = TREE_OPERAND (expr, 1);
14522 if (TREE_CODE (expr) == BASELINK)
14525 expr = BASELINK_FUNCTIONS (expr);
14528 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
14531 tree goodfn = NULL_TREE;
14533 /* If we got some explicit template args, we need to plug them into
14534 the affected templates before we try to unify, in case the
14535 explicit args will completely resolve the templates in question. */
14537 tree expl_subargs = TREE_OPERAND (expr, 1);
14538 tree arg = TREE_OPERAND (expr, 0);
14539 tree badfn = NULL_TREE;
14540 tree badargs = NULL_TREE;
14542 for (; arg; arg = OVL_NEXT (arg))
14544 tree fn = OVL_CURRENT (arg);
14545 tree subargs, elem;
14547 if (TREE_CODE (fn) != TEMPLATE_DECL)
14550 ++processing_template_decl;
14551 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14552 expl_subargs, /*check_ret=*/false);
14553 if (subargs && !any_dependent_template_arguments_p (subargs))
14555 elem = instantiate_template (fn, subargs, tf_none);
14556 if (elem == error_mark_node)
14561 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
14567 --processing_template_decl;
14573 expr = build_baselink (BASELINK_BINFO (baselink),
14574 BASELINK_ACCESS_BINFO (baselink),
14575 expr, BASELINK_OPTYPE (baselink));
14579 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
14580 expr = build_offset_ref (base, expr, addr);
14583 expr = cp_build_addr_expr (expr, tf_warning_or_error);
14586 else if (good == 0 && badargs)
14587 /* There were no good options and at least one bad one, so let the
14588 user know what the problem is. */
14589 instantiate_template (badfn, badargs, tf_warning_or_error);
14594 /* Subroutine of resolve_overloaded_unification; does deduction for a single
14595 overload. Fills TARGS with any deduced arguments, or error_mark_node if
14596 different overloads deduce different arguments for a given parm.
14597 ADDR_P is true if the expression for which deduction is being
14598 performed was of the form "& fn" rather than simply "fn".
14600 Returns 1 on success. */
14603 try_one_overload (tree tparms,
14608 unification_kind_t strict,
14616 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14617 to function or pointer to member function argument if the set of
14618 overloaded functions does not contain function templates and at most
14619 one of a set of overloaded functions provides a unique match.
14621 So if this is a template, just return success. */
14623 if (uses_template_parms (arg))
14626 if (TREE_CODE (arg) == METHOD_TYPE)
14627 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14629 arg = build_pointer_type (arg);
14631 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14633 /* We don't copy orig_targs for this because if we have already deduced
14634 some template args from previous args, unify would complain when we
14635 try to deduce a template parameter for the same argument, even though
14636 there isn't really a conflict. */
14637 nargs = TREE_VEC_LENGTH (targs);
14638 tempargs = make_tree_vec (nargs);
14640 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14643 /* First make sure we didn't deduce anything that conflicts with
14644 explicitly specified args. */
14645 for (i = nargs; i--; )
14647 tree elt = TREE_VEC_ELT (tempargs, i);
14648 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14652 else if (uses_template_parms (elt))
14653 /* Since we're unifying against ourselves, we will fill in
14654 template args used in the function parm list with our own
14655 template parms. Discard them. */
14656 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14657 else if (oldelt && !template_args_equal (oldelt, elt))
14661 for (i = nargs; i--; )
14663 tree elt = TREE_VEC_ELT (tempargs, i);
14666 TREE_VEC_ELT (targs, i) = elt;
14672 /* PARM is a template class (perhaps with unbound template
14673 parameters). ARG is a fully instantiated type. If ARG can be
14674 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14675 TARGS are as for unify. */
14678 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14680 tree copy_of_targs;
14682 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14683 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14684 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14687 /* We need to make a new template argument vector for the call to
14688 unify. If we used TARGS, we'd clutter it up with the result of
14689 the attempted unification, even if this class didn't work out.
14690 We also don't want to commit ourselves to all the unifications
14691 we've already done, since unification is supposed to be done on
14692 an argument-by-argument basis. In other words, consider the
14693 following pathological case:
14695 template <int I, int J, int K>
14698 template <int I, int J>
14699 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14701 template <int I, int J, int K>
14702 void f(S<I, J, K>, S<I, I, I>);
14711 Now, by the time we consider the unification involving `s2', we
14712 already know that we must have `f<0, 0, 0>'. But, even though
14713 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14714 because there are two ways to unify base classes of S<0, 1, 2>
14715 with S<I, I, I>. If we kept the already deduced knowledge, we
14716 would reject the possibility I=1. */
14717 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14719 /* If unification failed, we're done. */
14720 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14721 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14727 /* Given a template type PARM and a class type ARG, find the unique
14728 base type in ARG that is an instance of PARM. We do not examine
14729 ARG itself; only its base-classes. If there is not exactly one
14730 appropriate base class, return NULL_TREE. PARM may be the type of
14731 a partial specialization, as well as a plain template type. Used
14735 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14737 tree rval = NULL_TREE;
14740 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14742 binfo = TYPE_BINFO (complete_type (arg));
14744 /* The type could not be completed. */
14747 /* Walk in inheritance graph order. The search order is not
14748 important, and this avoids multiple walks of virtual bases. */
14749 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14751 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14755 /* If there is more than one satisfactory baseclass, then:
14759 If they yield more than one possible deduced A, the type
14763 if (rval && !same_type_p (r, rval))
14773 /* Returns the level of DECL, which declares a template parameter. */
14776 template_decl_level (tree decl)
14778 switch (TREE_CODE (decl))
14781 case TEMPLATE_DECL:
14782 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14785 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14788 gcc_unreachable ();
14793 /* Decide whether ARG can be unified with PARM, considering only the
14794 cv-qualifiers of each type, given STRICT as documented for unify.
14795 Returns nonzero iff the unification is OK on that basis. */
14798 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14800 int arg_quals = cp_type_quals (arg);
14801 int parm_quals = cp_type_quals (parm);
14803 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14804 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14806 /* Although a CVR qualifier is ignored when being applied to a
14807 substituted template parameter ([8.3.2]/1 for example), that
14808 does not allow us to unify "const T" with "int&" because both
14809 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14810 It is ok when we're allowing additional CV qualifiers
14811 at the outer level [14.8.2.1]/3,1st bullet. */
14812 if ((TREE_CODE (arg) == REFERENCE_TYPE
14813 || TREE_CODE (arg) == FUNCTION_TYPE
14814 || TREE_CODE (arg) == METHOD_TYPE)
14815 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14818 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14819 && (parm_quals & TYPE_QUAL_RESTRICT))
14823 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14824 && (arg_quals & parm_quals) != parm_quals)
14827 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14828 && (parm_quals & arg_quals) != arg_quals)
14834 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14836 template_parm_level_and_index (tree parm, int* level, int* index)
14838 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14839 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14840 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14842 *index = TEMPLATE_TYPE_IDX (parm);
14843 *level = TEMPLATE_TYPE_LEVEL (parm);
14847 *index = TEMPLATE_PARM_IDX (parm);
14848 *level = TEMPLATE_PARM_LEVEL (parm);
14852 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14853 expansion at the end of PACKED_PARMS. Returns 0 if the type
14854 deduction succeeds, 1 otherwise. STRICT is the same as in
14855 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14856 call argument list. We'll need to adjust the arguments to make them
14857 types. SUBR tells us if this is from a recursive call to
14858 type_unification_real. */
14860 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14861 tree packed_args, int strict, bool call_args_p,
14865 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14866 tree pattern = PACK_EXPANSION_PATTERN (parm);
14867 tree pack, packs = NULL_TREE;
14868 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14869 int len = TREE_VEC_LENGTH (packed_args);
14871 /* Determine the parameter packs we will be deducing from the
14872 pattern, and record their current deductions. */
14873 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14874 pack; pack = TREE_CHAIN (pack))
14876 tree parm_pack = TREE_VALUE (pack);
14879 /* Determine the index and level of this parameter pack. */
14880 template_parm_level_and_index (parm_pack, &level, &idx);
14882 /* Keep track of the parameter packs and their corresponding
14884 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14885 TREE_TYPE (packs) = make_tree_vec (len - start);
14888 /* Loop through all of the arguments that have not yet been
14889 unified and unify each with the pattern. */
14890 for (i = start; i < len; i++)
14892 tree parm = pattern;
14894 /* For each parameter pack, clear out the deduced value so that
14895 we can deduce it again. */
14896 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14899 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14901 TMPL_ARG (targs, level, idx) = NULL_TREE;
14904 /* Unify the pattern with the current argument. */
14906 tree arg = TREE_VEC_ELT (packed_args, i);
14907 tree arg_expr = NULL_TREE;
14908 int arg_strict = strict;
14909 bool skip_arg_p = false;
14915 /* This mirrors what we do in type_unification_real. */
14919 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14920 | UNIFY_ALLOW_MORE_CV_QUAL
14921 | UNIFY_ALLOW_DERIVED);
14925 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14929 sub_strict = UNIFY_ALLOW_NONE;
14933 gcc_unreachable ();
14938 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14939 if (type_unknown_p (arg))
14941 /* [temp.deduct.type] A template-argument can be
14942 deduced from a pointer to function or pointer
14943 to member function argument if the set of
14944 overloaded functions does not contain function
14945 templates and at most one of a set of
14946 overloaded functions provides a unique
14949 if (resolve_overloaded_unification
14950 (tparms, targs, parm, arg,
14951 (unification_kind_t) strict,
14961 arg = unlowered_expr_type (arg);
14962 if (arg == error_mark_node)
14967 arg_strict = sub_strict;
14971 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
14972 &parm, &arg, arg_expr);
14977 /* For deduction from an init-list we need the actual list. */
14978 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14980 if (unify (tparms, targs, parm, arg, arg_strict))
14985 /* For each parameter pack, collect the deduced value. */
14986 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14989 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14991 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
14992 TMPL_ARG (targs, level, idx);
14996 /* Verify that the results of unification with the parameter packs
14997 produce results consistent with what we've seen before, and make
14998 the deduced argument packs available. */
14999 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15001 tree old_pack = TREE_VALUE (pack);
15002 tree new_args = TREE_TYPE (pack);
15003 int i, len = TREE_VEC_LENGTH (new_args);
15005 bool nondeduced_p = false;
15007 /* By default keep the original deduced argument pack.
15008 If necessary, more specific code is going to update the
15009 resulting deduced argument later down in this function. */
15010 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15011 TMPL_ARG (targs, level, idx) = old_pack;
15013 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15014 actually deduce anything. */
15015 for (i = 0; i < len && !nondeduced_p; ++i)
15016 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15017 nondeduced_p = true;
15021 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15023 /* Prepend the explicit arguments onto NEW_ARGS. */
15024 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15025 tree old_args = new_args;
15026 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
15027 int len = explicit_len + TREE_VEC_LENGTH (old_args);
15029 /* Copy the explicit arguments. */
15030 new_args = make_tree_vec (len);
15031 for (i = 0; i < explicit_len; i++)
15032 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
15034 /* Copy the deduced arguments. */
15035 for (; i < len; i++)
15036 TREE_VEC_ELT (new_args, i) =
15037 TREE_VEC_ELT (old_args, i - explicit_len);
15043 /* Build the deduced *_ARGUMENT_PACK. */
15044 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15046 result = make_node (NONTYPE_ARGUMENT_PACK);
15047 TREE_TYPE (result) =
15048 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15049 TREE_CONSTANT (result) = 1;
15052 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15054 SET_ARGUMENT_PACK_ARGS (result, new_args);
15056 /* Note the deduced argument packs for this parameter
15058 TMPL_ARG (targs, level, idx) = result;
15060 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15061 && (ARGUMENT_PACK_ARGS (old_pack)
15062 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15064 /* We only had the explicitly-provided arguments before, but
15065 now we have a complete set of arguments. */
15066 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15068 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15069 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15070 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15072 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
15074 /* Inconsistent unification of this parameter pack. */
15081 /* Deduce the value of template parameters. TPARMS is the (innermost)
15082 set of template parameters to a template. TARGS is the bindings
15083 for those template parameters, as determined thus far; TARGS may
15084 include template arguments for outer levels of template parameters
15085 as well. PARM is a parameter to a template function, or a
15086 subcomponent of that parameter; ARG is the corresponding argument.
15087 This function attempts to match PARM with ARG in a manner
15088 consistent with the existing assignments in TARGS. If more values
15089 are deduced, then TARGS is updated.
15091 Returns 0 if the type deduction succeeds, 1 otherwise. The
15092 parameter STRICT is a bitwise or of the following flags:
15095 Require an exact match between PARM and ARG.
15096 UNIFY_ALLOW_MORE_CV_QUAL:
15097 Allow the deduced ARG to be more cv-qualified (by qualification
15098 conversion) than ARG.
15099 UNIFY_ALLOW_LESS_CV_QUAL:
15100 Allow the deduced ARG to be less cv-qualified than ARG.
15101 UNIFY_ALLOW_DERIVED:
15102 Allow the deduced ARG to be a template base class of ARG,
15103 or a pointer to a template base class of the type pointed to by
15105 UNIFY_ALLOW_INTEGER:
15106 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15107 case for more information.
15108 UNIFY_ALLOW_OUTER_LEVEL:
15109 This is the outermost level of a deduction. Used to determine validity
15110 of qualification conversions. A valid qualification conversion must
15111 have const qualified pointers leading up to the inner type which
15112 requires additional CV quals, except at the outer level, where const
15113 is not required [conv.qual]. It would be normal to set this flag in
15114 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15115 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15116 This is the outermost level of a deduction, and PARM can be more CV
15117 qualified at this point.
15118 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15119 This is the outermost level of a deduction, and PARM can be less CV
15120 qualified at this point. */
15123 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
15128 int strict_in = strict;
15130 /* I don't think this will do the right thing with respect to types.
15131 But the only case I've seen it in so far has been array bounds, where
15132 signedness is the only information lost, and I think that will be
15134 while (TREE_CODE (parm) == NOP_EXPR)
15135 parm = TREE_OPERAND (parm, 0);
15137 if (arg == error_mark_node)
15139 if (arg == unknown_type_node
15140 || arg == init_list_type_node)
15141 /* We can't deduce anything from this, but we might get all the
15142 template args from other function args. */
15145 /* If PARM uses template parameters, then we can't bail out here,
15146 even if ARG == PARM, since we won't record unifications for the
15147 template parameters. We might need them if we're trying to
15148 figure out which of two things is more specialized. */
15149 if (arg == parm && !uses_template_parms (parm))
15152 /* Handle init lists early, so the rest of the function can assume
15153 we're dealing with a type. */
15154 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15158 tree orig_parm = parm;
15160 /* Replace T with std::initializer_list<T> for deduction. */
15161 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15162 && flag_deduce_init_list)
15163 parm = listify (parm);
15165 if (!is_std_init_list (parm))
15166 /* We can only deduce from an initializer list argument if the
15167 parameter is std::initializer_list; otherwise this is a
15168 non-deduced context. */
15171 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15173 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15175 int elt_strict = strict;
15177 if (elt == error_mark_node)
15180 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15182 tree type = TREE_TYPE (elt);
15183 /* It should only be possible to get here for a call. */
15184 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15185 elt_strict |= maybe_adjust_types_for_deduction
15186 (DEDUCE_CALL, &elttype, &type, elt);
15190 if (unify (tparms, targs, elttype, elt, elt_strict))
15194 /* If the std::initializer_list<T> deduction worked, replace the
15195 deduced A with std::initializer_list<A>. */
15196 if (orig_parm != parm)
15198 idx = TEMPLATE_TYPE_IDX (orig_parm);
15199 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15200 targ = listify (targ);
15201 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15206 /* Immediately reject some pairs that won't unify because of
15207 cv-qualification mismatches. */
15208 if (TREE_CODE (arg) == TREE_CODE (parm)
15210 /* It is the elements of the array which hold the cv quals of an array
15211 type, and the elements might be template type parms. We'll check
15212 when we recurse. */
15213 && TREE_CODE (arg) != ARRAY_TYPE
15214 /* We check the cv-qualifiers when unifying with template type
15215 parameters below. We want to allow ARG `const T' to unify with
15216 PARM `T' for example, when computing which of two templates
15217 is more specialized, for example. */
15218 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15219 && !check_cv_quals_for_unify (strict_in, arg, parm))
15222 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15223 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15224 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15225 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15226 strict &= ~UNIFY_ALLOW_DERIVED;
15227 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15228 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15230 switch (TREE_CODE (parm))
15232 case TYPENAME_TYPE:
15234 case UNBOUND_CLASS_TEMPLATE:
15235 /* In a type which contains a nested-name-specifier, template
15236 argument values cannot be deduced for template parameters used
15237 within the nested-name-specifier. */
15240 case TEMPLATE_TYPE_PARM:
15241 case TEMPLATE_TEMPLATE_PARM:
15242 case BOUND_TEMPLATE_TEMPLATE_PARM:
15243 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15244 if (tparm == error_mark_node)
15247 if (TEMPLATE_TYPE_LEVEL (parm)
15248 != template_decl_level (tparm))
15249 /* The PARM is not one we're trying to unify. Just check
15250 to see if it matches ARG. */
15251 return (TREE_CODE (arg) == TREE_CODE (parm)
15252 && same_type_p (parm, arg)) ? 0 : 1;
15253 idx = TEMPLATE_TYPE_IDX (parm);
15254 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15255 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15257 /* Check for mixed types and values. */
15258 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15259 && TREE_CODE (tparm) != TYPE_DECL)
15260 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15261 && TREE_CODE (tparm) != TEMPLATE_DECL))
15264 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15266 /* ARG must be constructed from a template class or a template
15267 template parameter. */
15268 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15269 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15273 tree parmvec = TYPE_TI_ARGS (parm);
15274 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15275 tree full_argvec = add_to_template_args (targs, argvec);
15277 = DECL_INNERMOST_TEMPLATE_PARMS
15278 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15280 int parm_variadic_p = 0;
15282 /* The resolution to DR150 makes clear that default
15283 arguments for an N-argument may not be used to bind T
15284 to a template template parameter with fewer than N
15285 parameters. It is not safe to permit the binding of
15286 default arguments as an extension, as that may change
15287 the meaning of a conforming program. Consider:
15289 struct Dense { static const unsigned int dim = 1; };
15291 template <template <typename> class View,
15293 void operator+(float, View<Block> const&);
15295 template <typename Block,
15296 unsigned int Dim = Block::dim>
15297 struct Lvalue_proxy { operator float() const; };
15301 Lvalue_proxy<Dense> p;
15306 Here, if Lvalue_proxy is permitted to bind to View, then
15307 the global operator+ will be used; if they are not, the
15308 Lvalue_proxy will be converted to float. */
15309 if (coerce_template_parms (parm_parms,
15311 TYPE_TI_TEMPLATE (parm),
15313 /*require_all_args=*/true,
15314 /*use_default_args=*/false)
15315 == error_mark_node)
15318 /* Deduce arguments T, i from TT<T> or TT<i>.
15319 We check each element of PARMVEC and ARGVEC individually
15320 rather than the whole TREE_VEC since they can have
15321 different number of elements. */
15323 parmvec = expand_template_argument_pack (parmvec);
15324 argvec = expand_template_argument_pack (argvec);
15326 len = TREE_VEC_LENGTH (parmvec);
15328 /* Check if the parameters end in a pack, making them
15331 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15332 parm_variadic_p = 1;
15334 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15337 for (i = 0; i < len - parm_variadic_p; ++i)
15339 if (unify (tparms, targs,
15340 TREE_VEC_ELT (parmvec, i),
15341 TREE_VEC_ELT (argvec, i),
15346 if (parm_variadic_p
15347 && unify_pack_expansion (tparms, targs,
15350 /*call_args_p=*/false,
15354 arg = TYPE_TI_TEMPLATE (arg);
15356 /* Fall through to deduce template name. */
15359 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15360 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15362 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15364 /* Simple cases: Value already set, does match or doesn't. */
15365 if (targ != NULL_TREE && template_args_equal (targ, arg))
15372 /* If PARM is `const T' and ARG is only `int', we don't have
15373 a match unless we are allowing additional qualification.
15374 If ARG is `const int' and PARM is just `T' that's OK;
15375 that binds `const int' to `T'. */
15376 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15380 /* Consider the case where ARG is `const volatile int' and
15381 PARM is `const T'. Then, T should be `volatile int'. */
15382 arg = cp_build_qualified_type_real
15383 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15384 if (arg == error_mark_node)
15387 /* Simple cases: Value already set, does match or doesn't. */
15388 if (targ != NULL_TREE && same_type_p (targ, arg))
15393 /* Make sure that ARG is not a variable-sized array. (Note
15394 that were talking about variable-sized arrays (like
15395 `int[n]'), rather than arrays of unknown size (like
15396 `int[]').) We'll get very confused by such a type since
15397 the bound of the array will not be computable in an
15398 instantiation. Besides, such types are not allowed in
15399 ISO C++, so we can do as we please here. */
15400 if (variably_modified_type_p (arg, NULL_TREE))
15403 /* Strip typedefs as in convert_template_argument. */
15404 arg = strip_typedefs (arg);
15407 /* If ARG is a parameter pack or an expansion, we cannot unify
15408 against it unless PARM is also a parameter pack. */
15409 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15410 && !template_parameter_pack_p (parm))
15413 /* If the argument deduction results is a METHOD_TYPE,
15414 then there is a problem.
15415 METHOD_TYPE doesn't map to any real C++ type the result of
15416 the deduction can not be of that type. */
15417 if (TREE_CODE (arg) == METHOD_TYPE)
15420 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15423 case TEMPLATE_PARM_INDEX:
15424 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15425 if (tparm == error_mark_node)
15428 if (TEMPLATE_PARM_LEVEL (parm)
15429 != template_decl_level (tparm))
15430 /* The PARM is not one we're trying to unify. Just check
15431 to see if it matches ARG. */
15432 return !(TREE_CODE (arg) == TREE_CODE (parm)
15433 && cp_tree_equal (parm, arg));
15435 idx = TEMPLATE_PARM_IDX (parm);
15436 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15439 return !cp_tree_equal (targ, arg);
15441 /* [temp.deduct.type] If, in the declaration of a function template
15442 with a non-type template-parameter, the non-type
15443 template-parameter is used in an expression in the function
15444 parameter-list and, if the corresponding template-argument is
15445 deduced, the template-argument type shall match the type of the
15446 template-parameter exactly, except that a template-argument
15447 deduced from an array bound may be of any integral type.
15448 The non-type parameter might use already deduced type parameters. */
15449 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
15450 if (!TREE_TYPE (arg))
15451 /* Template-parameter dependent expression. Just accept it for now.
15452 It will later be processed in convert_template_argument. */
15454 else if (same_type_p (TREE_TYPE (arg), tparm))
15456 else if ((strict & UNIFY_ALLOW_INTEGER)
15457 && (TREE_CODE (tparm) == INTEGER_TYPE
15458 || TREE_CODE (tparm) == BOOLEAN_TYPE))
15459 /* Convert the ARG to the type of PARM; the deduced non-type
15460 template argument must exactly match the types of the
15461 corresponding parameter. */
15462 arg = fold (build_nop (tparm, arg));
15463 else if (uses_template_parms (tparm))
15464 /* We haven't deduced the type of this parameter yet. Try again
15470 /* If ARG is a parameter pack or an expansion, we cannot unify
15471 against it unless PARM is also a parameter pack. */
15472 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15473 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
15476 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15481 /* A pointer-to-member constant can be unified only with
15482 another constant. */
15483 if (TREE_CODE (arg) != PTRMEM_CST)
15486 /* Just unify the class member. It would be useless (and possibly
15487 wrong, depending on the strict flags) to unify also
15488 PTRMEM_CST_CLASS, because we want to be sure that both parm and
15489 arg refer to the same variable, even if through different
15490 classes. For instance:
15492 struct A { int x; };
15495 Unification of &A::x and &B::x must succeed. */
15496 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
15497 PTRMEM_CST_MEMBER (arg), strict);
15502 if (TREE_CODE (arg) != POINTER_TYPE)
15505 /* [temp.deduct.call]
15507 A can be another pointer or pointer to member type that can
15508 be converted to the deduced A via a qualification
15509 conversion (_conv.qual_).
15511 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
15512 This will allow for additional cv-qualification of the
15513 pointed-to types if appropriate. */
15515 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
15516 /* The derived-to-base conversion only persists through one
15517 level of pointers. */
15518 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
15520 return unify (tparms, targs, TREE_TYPE (parm),
15521 TREE_TYPE (arg), strict);
15524 case REFERENCE_TYPE:
15525 if (TREE_CODE (arg) != REFERENCE_TYPE)
15527 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15528 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15531 if (TREE_CODE (arg) != ARRAY_TYPE)
15533 if ((TYPE_DOMAIN (parm) == NULL_TREE)
15534 != (TYPE_DOMAIN (arg) == NULL_TREE))
15536 if (TYPE_DOMAIN (parm) != NULL_TREE)
15543 /* Our representation of array types uses "N - 1" as the
15544 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
15545 not an integer constant. We cannot unify arbitrarily
15546 complex expressions, so we eliminate the MINUS_EXPRs
15548 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
15549 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
15552 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
15553 parm_max = TREE_OPERAND (parm_max, 0);
15555 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
15556 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
15559 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
15560 trying to unify the type of a variable with the type
15561 of a template parameter. For example:
15563 template <unsigned int N>
15564 void f (char (&) [N]);
15571 Here, the type of the ARG will be "int [g(i)]", and
15572 may be a SAVE_EXPR, etc. */
15573 if (TREE_CODE (arg_max) != MINUS_EXPR)
15575 arg_max = TREE_OPERAND (arg_max, 0);
15578 /* If only one of the bounds used a MINUS_EXPR, compensate
15579 by adding one to the other bound. */
15580 if (parm_cst && !arg_cst)
15581 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
15585 else if (arg_cst && !parm_cst)
15586 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
15591 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
15594 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15595 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15602 case ENUMERAL_TYPE:
15604 if (TREE_CODE (arg) != TREE_CODE (parm))
15607 /* We have already checked cv-qualification at the top of the
15609 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15612 /* As far as unification is concerned, this wins. Later checks
15613 will invalidate it if necessary. */
15616 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15617 /* Type INTEGER_CST can come from ordinary constant template args. */
15619 while (TREE_CODE (arg) == NOP_EXPR)
15620 arg = TREE_OPERAND (arg, 0);
15622 if (TREE_CODE (arg) != INTEGER_CST)
15624 return !tree_int_cst_equal (parm, arg);
15629 if (TREE_CODE (arg) != TREE_VEC)
15631 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15633 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15634 if (unify (tparms, targs,
15635 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15643 if (TREE_CODE (arg) != TREE_CODE (parm))
15646 if (TYPE_PTRMEMFUNC_P (parm))
15648 if (!TYPE_PTRMEMFUNC_P (arg))
15651 return unify (tparms, targs,
15652 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15653 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15657 if (CLASSTYPE_TEMPLATE_INFO (parm))
15659 tree t = NULL_TREE;
15661 if (strict_in & UNIFY_ALLOW_DERIVED)
15663 /* First, we try to unify the PARM and ARG directly. */
15664 t = try_class_unification (tparms, targs,
15669 /* Fallback to the special case allowed in
15670 [temp.deduct.call]:
15672 If P is a class, and P has the form
15673 template-id, then A can be a derived class of
15674 the deduced A. Likewise, if P is a pointer to
15675 a class of the form template-id, A can be a
15676 pointer to a derived class pointed to by the
15678 t = get_template_base (tparms, targs, parm, arg);
15684 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15685 && (CLASSTYPE_TI_TEMPLATE (parm)
15686 == CLASSTYPE_TI_TEMPLATE (arg)))
15687 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15688 Then, we should unify `int' and `U'. */
15691 /* There's no chance of unification succeeding. */
15694 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15695 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15697 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15702 case FUNCTION_TYPE:
15704 unsigned int nargs;
15709 if (TREE_CODE (arg) != TREE_CODE (parm))
15712 /* CV qualifications for methods can never be deduced, they must
15713 match exactly. We need to check them explicitly here,
15714 because type_unification_real treats them as any other
15715 cv-qualified parameter. */
15716 if (TREE_CODE (parm) == METHOD_TYPE
15717 && (!check_cv_quals_for_unify
15719 class_of_this_parm (arg),
15720 class_of_this_parm (parm))))
15723 if (unify (tparms, targs, TREE_TYPE (parm),
15724 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15727 nargs = list_length (TYPE_ARG_TYPES (arg));
15728 args = XALLOCAVEC (tree, nargs);
15729 for (a = TYPE_ARG_TYPES (arg), i = 0;
15730 a != NULL_TREE && a != void_list_node;
15731 a = TREE_CHAIN (a), ++i)
15732 args[i] = TREE_VALUE (a);
15735 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15736 args, nargs, 1, DEDUCE_EXACT,
15741 /* Unify a pointer to member with a pointer to member function, which
15742 deduces the type of the member as a function type. */
15743 if (TYPE_PTRMEMFUNC_P (arg))
15748 /* Check top-level cv qualifiers */
15749 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15752 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15753 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15756 /* Determine the type of the function we are unifying against. */
15757 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15759 build_function_type (TREE_TYPE (method_type),
15760 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15762 /* Extract the cv-qualifiers of the member function from the
15763 implicit object parameter and place them on the function
15764 type to be restored later. */
15765 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15766 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15769 if (TREE_CODE (arg) != OFFSET_TYPE)
15771 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15772 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15774 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15778 if (DECL_TEMPLATE_PARM_P (parm))
15779 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15780 if (arg != integral_constant_value (parm))
15785 case TEMPLATE_DECL:
15786 /* Matched cases are handled by the ARG == PARM test above. */
15790 /* A non-type template parameter that is a variable should be a
15791 an integral constant, in which case, it whould have been
15792 folded into its (constant) value. So we should not be getting
15793 a variable here. */
15794 gcc_unreachable ();
15796 case TYPE_ARGUMENT_PACK:
15797 case NONTYPE_ARGUMENT_PACK:
15799 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15800 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15801 int i, len = TREE_VEC_LENGTH (packed_parms);
15802 int argslen = TREE_VEC_LENGTH (packed_args);
15803 int parm_variadic_p = 0;
15805 for (i = 0; i < len; ++i)
15807 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15810 /* We can unify against something with a trailing
15812 parm_variadic_p = 1;
15814 /* Since there is something following the pack
15815 expansion, we cannot unify this template argument
15822 /* If we don't have enough arguments to satisfy the parameters
15823 (not counting the pack expression at the end), or we have
15824 too many arguments for a parameter list that doesn't end in
15825 a pack expression, we can't unify. */
15826 if (argslen < (len - parm_variadic_p)
15827 || (argslen > len && !parm_variadic_p))
15830 /* Unify all of the parameters that precede the (optional)
15831 pack expression. */
15832 for (i = 0; i < len - parm_variadic_p; ++i)
15834 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15835 TREE_VEC_ELT (packed_args, i), strict))
15839 if (parm_variadic_p)
15840 return unify_pack_expansion (tparms, targs,
15841 packed_parms, packed_args,
15842 strict, /*call_args_p=*/false,
15850 case DECLTYPE_TYPE:
15851 case UNDERLYING_TYPE:
15852 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
15853 or UNDERLYING_TYPE nodes. */
15857 /* Unification fails if we hit an error node. */
15861 /* An unresolved overload is a nondeduced context. */
15862 if (type_unknown_p (parm))
15864 gcc_assert (EXPR_P (parm));
15866 /* We must be looking at an expression. This can happen with
15870 void foo(S<I>, S<I + 2>);
15872 This is a "nondeduced context":
15876 The nondeduced contexts are:
15878 --A type that is a template-id in which one or more of
15879 the template-arguments is an expression that references
15880 a template-parameter.
15882 In these cases, we assume deduction succeeded, but don't
15883 actually infer any unifications. */
15885 if (!uses_template_parms (parm)
15886 && !template_args_equal (parm, arg))
15893 /* Note that DECL can be defined in this translation unit, if
15897 mark_definable (tree decl)
15900 DECL_NOT_REALLY_EXTERN (decl) = 1;
15901 FOR_EACH_CLONE (clone, decl)
15902 DECL_NOT_REALLY_EXTERN (clone) = 1;
15905 /* Called if RESULT is explicitly instantiated, or is a member of an
15906 explicitly instantiated class. */
15909 mark_decl_instantiated (tree result, int extern_p)
15911 SET_DECL_EXPLICIT_INSTANTIATION (result);
15913 /* If this entity has already been written out, it's too late to
15914 make any modifications. */
15915 if (TREE_ASM_WRITTEN (result))
15918 if (TREE_CODE (result) != FUNCTION_DECL)
15919 /* The TREE_PUBLIC flag for function declarations will have been
15920 set correctly by tsubst. */
15921 TREE_PUBLIC (result) = 1;
15923 /* This might have been set by an earlier implicit instantiation. */
15924 DECL_COMDAT (result) = 0;
15927 DECL_NOT_REALLY_EXTERN (result) = 0;
15930 mark_definable (result);
15931 /* Always make artificials weak. */
15932 if (DECL_ARTIFICIAL (result) && flag_weak)
15933 comdat_linkage (result);
15934 /* For WIN32 we also want to put explicit instantiations in
15935 linkonce sections. */
15936 else if (TREE_PUBLIC (result))
15937 maybe_make_one_only (result);
15940 /* If EXTERN_P, then this function will not be emitted -- unless
15941 followed by an explicit instantiation, at which point its linkage
15942 will be adjusted. If !EXTERN_P, then this function will be
15943 emitted here. In neither circumstance do we want
15944 import_export_decl to adjust the linkage. */
15945 DECL_INTERFACE_KNOWN (result) = 1;
15948 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
15949 important template arguments. If any are missing, we check whether
15950 they're important by using error_mark_node for substituting into any
15951 args that were used for partial ordering (the ones between ARGS and END)
15952 and seeing if it bubbles up. */
15955 check_undeduced_parms (tree targs, tree args, tree end)
15957 bool found = false;
15959 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
15960 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
15963 TREE_VEC_ELT (targs, i) = error_mark_node;
15967 for (; args != end; args = TREE_CHAIN (args))
15969 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
15970 if (substed == error_mark_node)
15977 /* Given two function templates PAT1 and PAT2, return:
15979 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
15980 -1 if PAT2 is more specialized than PAT1.
15981 0 if neither is more specialized.
15983 LEN indicates the number of parameters we should consider
15984 (defaulted parameters should not be considered).
15986 The 1998 std underspecified function template partial ordering, and
15987 DR214 addresses the issue. We take pairs of arguments, one from
15988 each of the templates, and deduce them against each other. One of
15989 the templates will be more specialized if all the *other*
15990 template's arguments deduce against its arguments and at least one
15991 of its arguments *does* *not* deduce against the other template's
15992 corresponding argument. Deduction is done as for class templates.
15993 The arguments used in deduction have reference and top level cv
15994 qualifiers removed. Iff both arguments were originally reference
15995 types *and* deduction succeeds in both directions, the template
15996 with the more cv-qualified argument wins for that pairing (if
15997 neither is more cv-qualified, they both are equal). Unlike regular
15998 deduction, after all the arguments have been deduced in this way,
15999 we do *not* verify the deduced template argument values can be
16000 substituted into non-deduced contexts.
16002 The logic can be a bit confusing here, because we look at deduce1 and
16003 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16004 can find template arguments for pat1 to make arg1 look like arg2, that
16005 means that arg2 is at least as specialized as arg1. */
16008 more_specialized_fn (tree pat1, tree pat2, int len)
16010 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16011 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16012 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16013 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16014 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16015 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16016 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16017 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16018 tree origs1, origs2;
16019 bool lose1 = false;
16020 bool lose2 = false;
16022 /* Remove the this parameter from non-static member functions. If
16023 one is a non-static member function and the other is not a static
16024 member function, remove the first parameter from that function
16025 also. This situation occurs for operator functions where we
16026 locate both a member function (with this pointer) and non-member
16027 operator (with explicit first operand). */
16028 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16030 len--; /* LEN is the number of significant arguments for DECL1 */
16031 args1 = TREE_CHAIN (args1);
16032 if (!DECL_STATIC_FUNCTION_P (decl2))
16033 args2 = TREE_CHAIN (args2);
16035 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16037 args2 = TREE_CHAIN (args2);
16038 if (!DECL_STATIC_FUNCTION_P (decl1))
16041 args1 = TREE_CHAIN (args1);
16045 /* If only one is a conversion operator, they are unordered. */
16046 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16049 /* Consider the return type for a conversion function */
16050 if (DECL_CONV_FN_P (decl1))
16052 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16053 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16057 processing_template_decl++;
16063 /* Stop when an ellipsis is seen. */
16064 && args1 != NULL_TREE && args2 != NULL_TREE)
16066 tree arg1 = TREE_VALUE (args1);
16067 tree arg2 = TREE_VALUE (args2);
16068 int deduce1, deduce2;
16072 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16073 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16075 /* When both arguments are pack expansions, we need only
16076 unify the patterns themselves. */
16077 arg1 = PACK_EXPANSION_PATTERN (arg1);
16078 arg2 = PACK_EXPANSION_PATTERN (arg2);
16080 /* This is the last comparison we need to do. */
16084 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16086 arg1 = TREE_TYPE (arg1);
16087 quals1 = cp_type_quals (arg1);
16090 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16092 arg2 = TREE_TYPE (arg2);
16093 quals2 = cp_type_quals (arg2);
16096 if ((quals1 < 0) != (quals2 < 0))
16098 /* Only of the args is a reference, see if we should apply
16099 array/function pointer decay to it. This is not part of
16100 DR214, but is, IMHO, consistent with the deduction rules
16101 for the function call itself, and with our earlier
16102 implementation of the underspecified partial ordering
16103 rules. (nathan). */
16106 switch (TREE_CODE (arg1))
16109 arg1 = TREE_TYPE (arg1);
16111 case FUNCTION_TYPE:
16112 arg1 = build_pointer_type (arg1);
16121 switch (TREE_CODE (arg2))
16124 arg2 = TREE_TYPE (arg2);
16126 case FUNCTION_TYPE:
16127 arg2 = build_pointer_type (arg2);
16136 arg1 = TYPE_MAIN_VARIANT (arg1);
16137 arg2 = TYPE_MAIN_VARIANT (arg2);
16139 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16141 int i, len2 = list_length (args2);
16142 tree parmvec = make_tree_vec (1);
16143 tree argvec = make_tree_vec (len2);
16146 /* Setup the parameter vector, which contains only ARG1. */
16147 TREE_VEC_ELT (parmvec, 0) = arg1;
16149 /* Setup the argument vector, which contains the remaining
16151 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16152 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16154 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
16155 argvec, UNIFY_ALLOW_NONE,
16156 /*call_args_p=*/false,
16159 /* We cannot deduce in the other direction, because ARG1 is
16160 a pack expansion but ARG2 is not. */
16163 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16165 int i, len1 = list_length (args1);
16166 tree parmvec = make_tree_vec (1);
16167 tree argvec = make_tree_vec (len1);
16170 /* Setup the parameter vector, which contains only ARG1. */
16171 TREE_VEC_ELT (parmvec, 0) = arg2;
16173 /* Setup the argument vector, which contains the remaining
16175 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16176 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16178 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
16179 argvec, UNIFY_ALLOW_NONE,
16180 /*call_args_p=*/false,
16183 /* We cannot deduce in the other direction, because ARG2 is
16184 a pack expansion but ARG1 is not.*/
16190 /* The normal case, where neither argument is a pack
16192 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
16193 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
16196 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16197 arg2, then arg2 is not as specialized as arg1. */
16203 /* "If, for a given type, deduction succeeds in both directions
16204 (i.e., the types are identical after the transformations above)
16205 and if the type from the argument template is more cv-qualified
16206 than the type from the parameter template (as described above)
16207 that type is considered to be more specialized than the other. If
16208 neither type is more cv-qualified than the other then neither type
16209 is more specialized than the other." */
16211 if (deduce1 && deduce2
16212 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16214 if ((quals1 & quals2) == quals2)
16216 if ((quals1 & quals2) == quals1)
16220 if (lose1 && lose2)
16221 /* We've failed to deduce something in either direction.
16222 These must be unordered. */
16225 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16226 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16227 /* We have already processed all of the arguments in our
16228 handing of the pack expansion type. */
16231 args1 = TREE_CHAIN (args1);
16232 args2 = TREE_CHAIN (args2);
16235 /* "In most cases, all template parameters must have values in order for
16236 deduction to succeed, but for partial ordering purposes a template
16237 parameter may remain without a value provided it is not used in the
16238 types being used for partial ordering."
16240 Thus, if we are missing any of the targs1 we need to substitute into
16241 origs1, then pat2 is not as specialized as pat1. This can happen when
16242 there is a nondeduced context. */
16243 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16245 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16248 processing_template_decl--;
16250 /* All things being equal, if the next argument is a pack expansion
16251 for one function but not for the other, prefer the
16252 non-variadic function. FIXME this is bogus; see c++/41958. */
16254 && args1 && TREE_VALUE (args1)
16255 && args2 && TREE_VALUE (args2))
16257 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16258 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16261 if (lose1 == lose2)
16269 /* Determine which of two partial specializations is more specialized.
16271 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16272 to the first partial specialization. The TREE_VALUE is the
16273 innermost set of template parameters for the partial
16274 specialization. PAT2 is similar, but for the second template.
16276 Return 1 if the first partial specialization is more specialized;
16277 -1 if the second is more specialized; 0 if neither is more
16280 See [temp.class.order] for information about determining which of
16281 two templates is more specialized. */
16284 more_specialized_class (tree pat1, tree pat2)
16289 bool any_deductions = false;
16291 tmpl1 = TREE_TYPE (pat1);
16292 tmpl2 = TREE_TYPE (pat2);
16294 /* Just like what happens for functions, if we are ordering between
16295 different class template specializations, we may encounter dependent
16296 types in the arguments, and we need our dependency check functions
16297 to behave correctly. */
16298 ++processing_template_decl;
16299 targs = get_class_bindings (TREE_VALUE (pat1),
16300 CLASSTYPE_TI_ARGS (tmpl1),
16301 CLASSTYPE_TI_ARGS (tmpl2));
16305 any_deductions = true;
16308 targs = get_class_bindings (TREE_VALUE (pat2),
16309 CLASSTYPE_TI_ARGS (tmpl2),
16310 CLASSTYPE_TI_ARGS (tmpl1));
16314 any_deductions = true;
16316 --processing_template_decl;
16318 /* In the case of a tie where at least one of the class templates
16319 has a parameter pack at the end, the template with the most
16320 non-packed parameters wins. */
16323 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16324 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16326 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16327 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16328 int len1 = TREE_VEC_LENGTH (args1);
16329 int len2 = TREE_VEC_LENGTH (args2);
16331 /* We don't count the pack expansion at the end. */
16332 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16334 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16339 else if (len1 < len2)
16346 /* Return the template arguments that will produce the function signature
16347 DECL from the function template FN, with the explicit template
16348 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16349 also match. Return NULL_TREE if no satisfactory arguments could be
16353 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16355 int ntparms = DECL_NTPARMS (fn);
16356 tree targs = make_tree_vec (ntparms);
16358 tree decl_arg_types;
16360 unsigned int nargs, ix;
16363 /* Substitute the explicit template arguments into the type of DECL.
16364 The call to fn_type_unification will handle substitution into the
16366 decl_type = TREE_TYPE (decl);
16367 if (explicit_args && uses_template_parms (decl_type))
16370 tree converted_args;
16372 if (DECL_TEMPLATE_INFO (decl))
16373 tmpl = DECL_TI_TEMPLATE (decl);
16375 /* We can get here for some invalid specializations. */
16379 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16380 explicit_args, NULL_TREE,
16382 /*require_all_args=*/false,
16383 /*use_default_args=*/false);
16384 if (converted_args == error_mark_node)
16387 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16388 if (decl_type == error_mark_node)
16392 /* Never do unification on the 'this' parameter. */
16393 decl_arg_types = skip_artificial_parms_for (decl,
16394 TYPE_ARG_TYPES (decl_type));
16396 nargs = list_length (decl_arg_types);
16397 args = XALLOCAVEC (tree, nargs);
16398 for (arg = decl_arg_types, ix = 0;
16399 arg != NULL_TREE && arg != void_list_node;
16400 arg = TREE_CHAIN (arg), ++ix)
16401 args[ix] = TREE_VALUE (arg);
16403 if (fn_type_unification (fn, explicit_args, targs,
16405 (check_rettype || DECL_CONV_FN_P (fn)
16406 ? TREE_TYPE (decl_type) : NULL_TREE),
16407 DEDUCE_EXACT, LOOKUP_NORMAL))
16413 /* Return the innermost template arguments that, when applied to a
16414 template specialization whose innermost template parameters are
16415 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
16418 For example, suppose we have:
16420 template <class T, class U> struct S {};
16421 template <class T> struct S<T*, int> {};
16423 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
16424 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
16425 int}. The resulting vector will be {double}, indicating that `T'
16426 is bound to `double'. */
16429 get_class_bindings (tree tparms, tree spec_args, tree args)
16431 int i, ntparms = TREE_VEC_LENGTH (tparms);
16433 tree innermost_deduced_args;
16435 innermost_deduced_args = make_tree_vec (ntparms);
16436 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16438 deduced_args = copy_node (args);
16439 SET_TMPL_ARGS_LEVEL (deduced_args,
16440 TMPL_ARGS_DEPTH (deduced_args),
16441 innermost_deduced_args);
16444 deduced_args = innermost_deduced_args;
16446 if (unify (tparms, deduced_args,
16447 INNERMOST_TEMPLATE_ARGS (spec_args),
16448 INNERMOST_TEMPLATE_ARGS (args),
16452 for (i = 0; i < ntparms; ++i)
16453 if (! TREE_VEC_ELT (innermost_deduced_args, i))
16456 /* Verify that nondeduced template arguments agree with the type
16457 obtained from argument deduction.
16461 struct A { typedef int X; };
16462 template <class T, class U> struct C {};
16463 template <class T> struct C<T, typename T::X> {};
16465 Then with the instantiation `C<A, int>', we can deduce that
16466 `T' is `A' but unify () does not check whether `typename T::X'
16468 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
16469 if (spec_args == error_mark_node
16470 /* We only need to check the innermost arguments; the other
16471 arguments will always agree. */
16472 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
16473 INNERMOST_TEMPLATE_ARGS (args)))
16476 /* Now that we have bindings for all of the template arguments,
16477 ensure that the arguments deduced for the template template
16478 parameters have compatible template parameter lists. See the use
16479 of template_template_parm_bindings_ok_p in fn_type_unification
16480 for more information. */
16481 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
16484 return deduced_args;
16487 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
16488 Return the TREE_LIST node with the most specialized template, if
16489 any. If there is no most specialized template, the error_mark_node
16492 Note that this function does not look at, or modify, the
16493 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
16494 returned is one of the elements of INSTANTIATIONS, callers may
16495 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
16496 and retrieve it from the value returned. */
16499 most_specialized_instantiation (tree templates)
16503 ++processing_template_decl;
16506 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
16510 if (get_bindings (TREE_VALUE (champ),
16511 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16512 NULL_TREE, /*check_ret=*/false))
16515 if (get_bindings (TREE_VALUE (fn),
16516 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16517 NULL_TREE, /*check_ret=*/false))
16524 /* Equally specialized, move to next function. If there
16525 is no next function, nothing's most specialized. */
16526 fn = TREE_CHAIN (fn);
16534 /* Now verify that champ is better than everything earlier in the
16535 instantiation list. */
16536 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
16537 if (get_bindings (TREE_VALUE (champ),
16538 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16539 NULL_TREE, /*check_ret=*/false)
16540 || !get_bindings (TREE_VALUE (fn),
16541 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16542 NULL_TREE, /*check_ret=*/false))
16548 processing_template_decl--;
16551 return error_mark_node;
16556 /* If DECL is a specialization of some template, return the most
16557 general such template. Otherwise, returns NULL_TREE.
16559 For example, given:
16561 template <class T> struct S { template <class U> void f(U); };
16563 if TMPL is `template <class U> void S<int>::f(U)' this will return
16564 the full template. This function will not trace past partial
16565 specializations, however. For example, given in addition:
16567 template <class T> struct S<T*> { template <class U> void f(U); };
16569 if TMPL is `template <class U> void S<int*>::f(U)' this will return
16570 `template <class T> template <class U> S<T*>::f(U)'. */
16573 most_general_template (tree decl)
16575 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
16576 an immediate specialization. */
16577 if (TREE_CODE (decl) == FUNCTION_DECL)
16579 if (DECL_TEMPLATE_INFO (decl)) {
16580 decl = DECL_TI_TEMPLATE (decl);
16582 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
16583 template friend. */
16584 if (TREE_CODE (decl) != TEMPLATE_DECL)
16590 /* Look for more and more general templates. */
16591 while (DECL_TEMPLATE_INFO (decl))
16593 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
16594 (See cp-tree.h for details.) */
16595 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
16598 if (CLASS_TYPE_P (TREE_TYPE (decl))
16599 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
16602 /* Stop if we run into an explicitly specialized class template. */
16603 if (!DECL_NAMESPACE_SCOPE_P (decl)
16604 && DECL_CONTEXT (decl)
16605 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16608 decl = DECL_TI_TEMPLATE (decl);
16614 /* Return the most specialized of the class template partial
16615 specializations of TMPL which can produce TYPE, a specialization of
16616 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16617 a _TYPE node corresponding to the partial specialization, while the
16618 TREE_PURPOSE is the set of template arguments that must be
16619 substituted into the TREE_TYPE in order to generate TYPE.
16621 If the choice of partial specialization is ambiguous, a diagnostic
16622 is issued, and the error_mark_node is returned. If there are no
16623 partial specializations of TMPL matching TYPE, then NULL_TREE is
16627 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16629 tree list = NULL_TREE;
16635 tree outer_args = NULL_TREE;
16637 tmpl = most_general_template (tmpl);
16638 args = CLASSTYPE_TI_ARGS (type);
16640 /* For determining which partial specialization to use, only the
16641 innermost args are interesting. */
16642 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16644 outer_args = strip_innermost_template_args (args, 1);
16645 args = INNERMOST_TEMPLATE_ARGS (args);
16648 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16650 tree partial_spec_args;
16652 tree parms = TREE_VALUE (t);
16654 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16656 ++processing_template_decl;
16662 /* Discard the outer levels of args, and then substitute in the
16663 template args from the enclosing class. */
16664 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16665 partial_spec_args = tsubst_template_args
16666 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16668 /* PARMS already refers to just the innermost parms, but the
16669 template parms in partial_spec_args had their levels lowered
16670 by tsubst, so we need to do the same for the parm list. We
16671 can't just tsubst the TREE_VEC itself, as tsubst wants to
16672 treat a TREE_VEC as an argument vector. */
16673 parms = copy_node (parms);
16674 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16675 TREE_VEC_ELT (parms, i) =
16676 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16680 partial_spec_args =
16681 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16682 add_to_template_args (outer_args,
16683 partial_spec_args),
16685 /*require_all_args=*/true,
16686 /*use_default_args=*/true);
16688 --processing_template_decl;
16690 if (partial_spec_args == error_mark_node)
16691 return error_mark_node;
16693 spec_args = get_class_bindings (parms,
16699 spec_args = add_to_template_args (outer_args, spec_args);
16700 list = tree_cons (spec_args, TREE_VALUE (t), list);
16701 TREE_TYPE (list) = TREE_TYPE (t);
16708 ambiguous_p = false;
16711 t = TREE_CHAIN (t);
16712 for (; t; t = TREE_CHAIN (t))
16714 fate = more_specialized_class (champ, t);
16721 t = TREE_CHAIN (t);
16724 ambiguous_p = true;
16733 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16735 fate = more_specialized_class (champ, t);
16738 ambiguous_p = true;
16746 char *spaces = NULL;
16747 if (!(complain & tf_error))
16748 return error_mark_node;
16749 error ("ambiguous class template instantiation for %q#T", type);
16750 str = ngettext ("candidate is:", "candidates are:", list_length (list));
16751 for (t = list; t; t = TREE_CHAIN (t))
16753 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16754 spaces = spaces ? spaces : get_spaces (str);
16757 return error_mark_node;
16763 /* Explicitly instantiate DECL. */
16766 do_decl_instantiation (tree decl, tree storage)
16768 tree result = NULL_TREE;
16771 if (!decl || decl == error_mark_node)
16772 /* An error occurred, for which grokdeclarator has already issued
16773 an appropriate message. */
16775 else if (! DECL_LANG_SPECIFIC (decl))
16777 error ("explicit instantiation of non-template %q#D", decl);
16780 else if (TREE_CODE (decl) == VAR_DECL)
16782 /* There is an asymmetry here in the way VAR_DECLs and
16783 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16784 the latter, the DECL we get back will be marked as a
16785 template instantiation, and the appropriate
16786 DECL_TEMPLATE_INFO will be set up. This does not happen for
16787 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16788 should handle VAR_DECLs as it currently handles
16790 if (!DECL_CLASS_SCOPE_P (decl))
16792 error ("%qD is not a static data member of a class template", decl);
16795 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16796 if (!result || TREE_CODE (result) != VAR_DECL)
16798 error ("no matching template for %qD found", decl);
16801 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16803 error ("type %qT for explicit instantiation %qD does not match "
16804 "declared type %qT", TREE_TYPE (result), decl,
16809 else if (TREE_CODE (decl) != FUNCTION_DECL)
16811 error ("explicit instantiation of %q#D", decl);
16817 /* Check for various error cases. Note that if the explicit
16818 instantiation is valid the RESULT will currently be marked as an
16819 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16820 until we get here. */
16822 if (DECL_TEMPLATE_SPECIALIZATION (result))
16824 /* DR 259 [temp.spec].
16826 Both an explicit instantiation and a declaration of an explicit
16827 specialization shall not appear in a program unless the explicit
16828 instantiation follows a declaration of the explicit specialization.
16830 For a given set of template parameters, if an explicit
16831 instantiation of a template appears after a declaration of an
16832 explicit specialization for that template, the explicit
16833 instantiation has no effect. */
16836 else if (DECL_EXPLICIT_INSTANTIATION (result))
16840 No program shall explicitly instantiate any template more
16843 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16844 the first instantiation was `extern' and the second is not,
16845 and EXTERN_P for the opposite case. */
16846 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16847 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16848 /* If an "extern" explicit instantiation follows an ordinary
16849 explicit instantiation, the template is instantiated. */
16853 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16855 error ("no matching template for %qD found", result);
16858 else if (!DECL_TEMPLATE_INFO (result))
16860 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16864 if (storage == NULL_TREE)
16866 else if (storage == ridpointers[(int) RID_EXTERN])
16868 if (!in_system_header && (cxx_dialect == cxx98))
16869 pedwarn (input_location, OPT_pedantic,
16870 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16875 error ("storage class %qD applied to template instantiation", storage);
16877 check_explicit_instantiation_namespace (result);
16878 mark_decl_instantiated (result, extern_p);
16880 instantiate_decl (result, /*defer_ok=*/1,
16881 /*expl_inst_class_mem_p=*/false);
16885 mark_class_instantiated (tree t, int extern_p)
16887 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16888 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16889 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16890 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16893 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16894 rest_of_type_compilation (t, 1);
16898 /* Called from do_type_instantiation through binding_table_foreach to
16899 do recursive instantiation for the type bound in ENTRY. */
16901 bt_instantiate_type_proc (binding_entry entry, void *data)
16903 tree storage = *(tree *) data;
16905 if (MAYBE_CLASS_TYPE_P (entry->type)
16906 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16907 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16910 /* Called from do_type_instantiation to instantiate a member
16911 (a member function or a static member variable) of an
16912 explicitly instantiated class template. */
16914 instantiate_class_member (tree decl, int extern_p)
16916 mark_decl_instantiated (decl, extern_p);
16918 instantiate_decl (decl, /*defer_ok=*/1,
16919 /*expl_inst_class_mem_p=*/true);
16922 /* Perform an explicit instantiation of template class T. STORAGE, if
16923 non-null, is the RID for extern, inline or static. COMPLAIN is
16924 nonzero if this is called from the parser, zero if called recursively,
16925 since the standard is unclear (as detailed below). */
16928 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16933 int previous_instantiation_extern_p = 0;
16935 if (TREE_CODE (t) == TYPE_DECL)
16938 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16940 error ("explicit instantiation of non-template type %qT", t);
16946 if (!COMPLETE_TYPE_P (t))
16948 if (complain & tf_error)
16949 error ("explicit instantiation of %q#T before definition of template",
16954 if (storage != NULL_TREE)
16956 if (!in_system_header)
16958 if (storage == ridpointers[(int) RID_EXTERN])
16960 if (cxx_dialect == cxx98)
16961 pedwarn (input_location, OPT_pedantic,
16962 "ISO C++ 1998 forbids the use of %<extern%> on "
16963 "explicit instantiations");
16966 pedwarn (input_location, OPT_pedantic,
16967 "ISO C++ forbids the use of %qE"
16968 " on explicit instantiations", storage);
16971 if (storage == ridpointers[(int) RID_INLINE])
16973 else if (storage == ridpointers[(int) RID_EXTERN])
16975 else if (storage == ridpointers[(int) RID_STATIC])
16979 error ("storage class %qD applied to template instantiation",
16985 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
16987 /* DR 259 [temp.spec].
16989 Both an explicit instantiation and a declaration of an explicit
16990 specialization shall not appear in a program unless the explicit
16991 instantiation follows a declaration of the explicit specialization.
16993 For a given set of template parameters, if an explicit
16994 instantiation of a template appears after a declaration of an
16995 explicit specialization for that template, the explicit
16996 instantiation has no effect. */
16999 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17003 No program shall explicitly instantiate any template more
17006 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17007 instantiation was `extern'. If EXTERN_P then the second is.
17008 These cases are OK. */
17009 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17011 if (!previous_instantiation_extern_p && !extern_p
17012 && (complain & tf_error))
17013 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17015 /* If we've already instantiated the template, just return now. */
17016 if (!CLASSTYPE_INTERFACE_ONLY (t))
17020 check_explicit_instantiation_namespace (TYPE_NAME (t));
17021 mark_class_instantiated (t, extern_p);
17029 /* In contrast to implicit instantiation, where only the
17030 declarations, and not the definitions, of members are
17031 instantiated, we have here:
17035 The explicit instantiation of a class template specialization
17036 implies the instantiation of all of its members not
17037 previously explicitly specialized in the translation unit
17038 containing the explicit instantiation.
17040 Of course, we can't instantiate member template classes, since
17041 we don't have any arguments for them. Note that the standard
17042 is unclear on whether the instantiation of the members are
17043 *explicit* instantiations or not. However, the most natural
17044 interpretation is that it should be an explicit instantiation. */
17047 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17048 if (TREE_CODE (tmp) == FUNCTION_DECL
17049 && DECL_TEMPLATE_INSTANTIATION (tmp))
17050 instantiate_class_member (tmp, extern_p);
17052 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17053 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17054 instantiate_class_member (tmp, extern_p);
17056 if (CLASSTYPE_NESTED_UTDS (t))
17057 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17058 bt_instantiate_type_proc, &storage);
17062 /* Given a function DECL, which is a specialization of TMPL, modify
17063 DECL to be a re-instantiation of TMPL with the same template
17064 arguments. TMPL should be the template into which tsubst'ing
17065 should occur for DECL, not the most general template.
17067 One reason for doing this is a scenario like this:
17070 void f(const T&, int i);
17072 void g() { f(3, 7); }
17075 void f(const T& t, const int i) { }
17077 Note that when the template is first instantiated, with
17078 instantiate_template, the resulting DECL will have no name for the
17079 first parameter, and the wrong type for the second. So, when we go
17080 to instantiate the DECL, we regenerate it. */
17083 regenerate_decl_from_template (tree decl, tree tmpl)
17085 /* The arguments used to instantiate DECL, from the most general
17090 args = DECL_TI_ARGS (decl);
17091 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17093 /* Make sure that we can see identifiers, and compute access
17095 push_access_scope (decl);
17097 if (TREE_CODE (decl) == FUNCTION_DECL)
17105 args_depth = TMPL_ARGS_DEPTH (args);
17106 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17107 if (args_depth > parms_depth)
17108 args = get_innermost_template_args (args, parms_depth);
17110 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17111 args, tf_error, NULL_TREE);
17113 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17116 /* Merge parameter declarations. */
17117 decl_parm = skip_artificial_parms_for (decl,
17118 DECL_ARGUMENTS (decl));
17120 = skip_artificial_parms_for (code_pattern,
17121 DECL_ARGUMENTS (code_pattern));
17122 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17127 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17128 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17129 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17131 parm_type = type_decays_to (parm_type);
17132 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17133 TREE_TYPE (decl_parm) = parm_type;
17134 attributes = DECL_ATTRIBUTES (pattern_parm);
17135 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17137 DECL_ATTRIBUTES (decl_parm) = attributes;
17138 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17140 decl_parm = DECL_CHAIN (decl_parm);
17141 pattern_parm = DECL_CHAIN (pattern_parm);
17143 /* Merge any parameters that match with the function parameter
17145 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17148 tree expanded_types;
17149 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17150 the parameters in this function parameter pack. */
17151 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17152 args, tf_error, NULL_TREE);
17153 len = TREE_VEC_LENGTH (expanded_types);
17154 for (i = 0; i < len; i++)
17159 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17160 /* Rename the parameter to include the index. */
17161 DECL_NAME (decl_parm) =
17162 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17163 parm_type = TREE_VEC_ELT (expanded_types, i);
17164 parm_type = type_decays_to (parm_type);
17165 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17166 TREE_TYPE (decl_parm) = parm_type;
17167 attributes = DECL_ATTRIBUTES (pattern_parm);
17168 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17170 DECL_ATTRIBUTES (decl_parm) = attributes;
17171 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17173 decl_parm = DECL_CHAIN (decl_parm);
17176 /* Merge additional specifiers from the CODE_PATTERN. */
17177 if (DECL_DECLARED_INLINE_P (code_pattern)
17178 && !DECL_DECLARED_INLINE_P (decl))
17179 DECL_DECLARED_INLINE_P (decl) = 1;
17181 else if (TREE_CODE (decl) == VAR_DECL)
17183 DECL_INITIAL (decl) =
17184 tsubst_expr (DECL_INITIAL (code_pattern), args,
17185 tf_error, DECL_TI_TEMPLATE (decl),
17186 /*integral_constant_expression_p=*/false);
17187 if (VAR_HAD_UNKNOWN_BOUND (decl))
17188 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17189 tf_error, DECL_TI_TEMPLATE (decl));
17192 gcc_unreachable ();
17194 pop_access_scope (decl);
17197 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17198 substituted to get DECL. */
17201 template_for_substitution (tree decl)
17203 tree tmpl = DECL_TI_TEMPLATE (decl);
17205 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17206 for the instantiation. This is not always the most general
17207 template. Consider, for example:
17210 struct S { template <class U> void f();
17211 template <> void f<int>(); };
17213 and an instantiation of S<double>::f<int>. We want TD to be the
17214 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17215 while (/* An instantiation cannot have a definition, so we need a
17216 more general template. */
17217 DECL_TEMPLATE_INSTANTIATION (tmpl)
17218 /* We must also deal with friend templates. Given:
17220 template <class T> struct S {
17221 template <class U> friend void f() {};
17224 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17225 so far as the language is concerned, but that's still
17226 where we get the pattern for the instantiation from. On
17227 other hand, if the definition comes outside the class, say:
17229 template <class T> struct S {
17230 template <class U> friend void f();
17232 template <class U> friend void f() {}
17234 we don't need to look any further. That's what the check for
17235 DECL_INITIAL is for. */
17236 || (TREE_CODE (decl) == FUNCTION_DECL
17237 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17238 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17240 /* The present template, TD, should not be a definition. If it
17241 were a definition, we should be using it! Note that we
17242 cannot restructure the loop to just keep going until we find
17243 a template with a definition, since that might go too far if
17244 a specialization was declared, but not defined. */
17245 gcc_assert (TREE_CODE (decl) != VAR_DECL
17246 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17248 /* Fetch the more general template. */
17249 tmpl = DECL_TI_TEMPLATE (tmpl);
17255 /* Returns true if we need to instantiate this template instance even if we
17256 know we aren't going to emit it.. */
17259 always_instantiate_p (tree decl)
17261 /* We always instantiate inline functions so that we can inline them. An
17262 explicit instantiation declaration prohibits implicit instantiation of
17263 non-inline functions. With high levels of optimization, we would
17264 normally inline non-inline functions -- but we're not allowed to do
17265 that for "extern template" functions. Therefore, we check
17266 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17267 return ((TREE_CODE (decl) == FUNCTION_DECL
17268 && DECL_DECLARED_INLINE_P (decl))
17269 /* And we need to instantiate static data members so that
17270 their initializers are available in integral constant
17272 || (TREE_CODE (decl) == VAR_DECL
17273 && decl_maybe_constant_var_p (decl)));
17276 /* Produce the definition of D, a _DECL generated from a template. If
17277 DEFER_OK is nonzero, then we don't have to actually do the
17278 instantiation now; we just have to do it sometime. Normally it is
17279 an error if this is an explicit instantiation but D is undefined.
17280 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17281 explicitly instantiated class template. */
17284 instantiate_decl (tree d, int defer_ok,
17285 bool expl_inst_class_mem_p)
17287 tree tmpl = DECL_TI_TEMPLATE (d);
17294 bool pattern_defined;
17296 location_t saved_loc = input_location;
17299 /* This function should only be used to instantiate templates for
17300 functions and static member variables. */
17301 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17302 || TREE_CODE (d) == VAR_DECL);
17304 /* Variables are never deferred; if instantiation is required, they
17305 are instantiated right away. That allows for better code in the
17306 case that an expression refers to the value of the variable --
17307 if the variable has a constant value the referring expression can
17308 take advantage of that fact. */
17309 if (TREE_CODE (d) == VAR_DECL
17310 || DECL_DECLARED_CONSTEXPR_P (d))
17313 /* Don't instantiate cloned functions. Instead, instantiate the
17314 functions they cloned. */
17315 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17316 d = DECL_CLONED_FUNCTION (d);
17318 if (DECL_TEMPLATE_INSTANTIATED (d)
17319 || DECL_TEMPLATE_SPECIALIZATION (d))
17320 /* D has already been instantiated or explicitly specialized, so
17321 there's nothing for us to do here.
17323 It might seem reasonable to check whether or not D is an explicit
17324 instantiation, and, if so, stop here. But when an explicit
17325 instantiation is deferred until the end of the compilation,
17326 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17327 the instantiation. */
17330 /* Check to see whether we know that this template will be
17331 instantiated in some other file, as with "extern template"
17333 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17335 /* In general, we do not instantiate such templates. */
17336 if (external_p && !always_instantiate_p (d))
17339 gen_tmpl = most_general_template (tmpl);
17340 gen_args = DECL_TI_ARGS (d);
17342 if (tmpl != gen_tmpl)
17343 /* We should already have the extra args. */
17344 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17345 == TMPL_ARGS_DEPTH (gen_args));
17346 /* And what's in the hash table should match D. */
17347 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17348 || spec == NULL_TREE);
17350 /* This needs to happen before any tsubsting. */
17351 if (! push_tinst_level (d))
17354 timevar_push (TV_TEMPLATE_INST);
17356 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
17357 for the instantiation. */
17358 td = template_for_substitution (d);
17359 code_pattern = DECL_TEMPLATE_RESULT (td);
17361 /* We should never be trying to instantiate a member of a class
17362 template or partial specialization. */
17363 gcc_assert (d != code_pattern);
17365 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
17366 || DECL_TEMPLATE_SPECIALIZATION (td))
17367 /* In the case of a friend template whose definition is provided
17368 outside the class, we may have too many arguments. Drop the
17369 ones we don't need. The same is true for specializations. */
17370 args = get_innermost_template_args
17371 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
17375 if (TREE_CODE (d) == FUNCTION_DECL)
17376 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
17378 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
17380 /* We may be in the middle of deferred access check. Disable it now. */
17381 push_deferring_access_checks (dk_no_deferred);
17383 /* Unless an explicit instantiation directive has already determined
17384 the linkage of D, remember that a definition is available for
17386 if (pattern_defined
17387 && !DECL_INTERFACE_KNOWN (d)
17388 && !DECL_NOT_REALLY_EXTERN (d))
17389 mark_definable (d);
17391 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
17392 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
17393 input_location = DECL_SOURCE_LOCATION (d);
17395 /* If D is a member of an explicitly instantiated class template,
17396 and no definition is available, treat it like an implicit
17398 if (!pattern_defined && expl_inst_class_mem_p
17399 && DECL_EXPLICIT_INSTANTIATION (d))
17401 /* Leave linkage flags alone on instantiations with anonymous
17403 if (TREE_PUBLIC (d))
17405 DECL_NOT_REALLY_EXTERN (d) = 0;
17406 DECL_INTERFACE_KNOWN (d) = 0;
17408 SET_DECL_IMPLICIT_INSTANTIATION (d);
17411 /* Recheck the substitutions to obtain any warning messages
17412 about ignoring cv qualifiers. Don't do this for artificial decls,
17413 as it breaks the context-sensitive substitution for lambda op(). */
17414 if (!defer_ok && !DECL_ARTIFICIAL (d))
17416 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
17417 tree type = TREE_TYPE (gen);
17419 /* Make sure that we can see identifiers, and compute access
17420 correctly. D is already the target FUNCTION_DECL with the
17422 push_access_scope (d);
17424 if (TREE_CODE (gen) == FUNCTION_DECL)
17426 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
17427 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
17429 /* Don't simply tsubst the function type, as that will give
17430 duplicate warnings about poor parameter qualifications.
17431 The function arguments are the same as the decl_arguments
17432 without the top level cv qualifiers. */
17433 type = TREE_TYPE (type);
17435 tsubst (type, gen_args, tf_warning_or_error, d);
17437 pop_access_scope (d);
17440 /* Defer all other templates, unless we have been explicitly
17441 forbidden from doing so. */
17442 if (/* If there is no definition, we cannot instantiate the
17445 /* If it's OK to postpone instantiation, do so. */
17447 /* If this is a static data member that will be defined
17448 elsewhere, we don't want to instantiate the entire data
17449 member, but we do want to instantiate the initializer so that
17450 we can substitute that elsewhere. */
17451 || (external_p && TREE_CODE (d) == VAR_DECL))
17453 /* The definition of the static data member is now required so
17454 we must substitute the initializer. */
17455 if (TREE_CODE (d) == VAR_DECL
17456 && !DECL_INITIAL (d)
17457 && DECL_INITIAL (code_pattern))
17461 bool const_init = false;
17463 ns = decl_namespace_context (d);
17464 push_nested_namespace (ns);
17465 push_nested_class (DECL_CONTEXT (d));
17466 init = tsubst_expr (DECL_INITIAL (code_pattern),
17468 tf_warning_or_error, NULL_TREE,
17469 /*integral_constant_expression_p=*/false);
17470 /* Make sure the initializer is still constant, in case of
17471 circular dependency (template/instantiate6.C). */
17473 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17474 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
17475 /*asmspec_tree=*/NULL_TREE,
17476 LOOKUP_ONLYCONVERTING);
17477 pop_nested_class ();
17478 pop_nested_namespace (ns);
17481 /* We restore the source position here because it's used by
17482 add_pending_template. */
17483 input_location = saved_loc;
17485 if (at_eof && !pattern_defined
17486 && DECL_EXPLICIT_INSTANTIATION (d)
17487 && DECL_NOT_REALLY_EXTERN (d))
17490 The definition of a non-exported function template, a
17491 non-exported member function template, or a non-exported
17492 member function or static data member of a class template
17493 shall be present in every translation unit in which it is
17494 explicitly instantiated. */
17495 permerror (input_location, "explicit instantiation of %qD "
17496 "but no definition available", d);
17498 /* If we're in unevaluated context, we just wanted to get the
17499 constant value; this isn't an odr use, so don't queue
17500 a full instantiation. */
17501 if (cp_unevaluated_operand != 0)
17503 /* ??? Historically, we have instantiated inline functions, even
17504 when marked as "extern template". */
17505 if (!(external_p && TREE_CODE (d) == VAR_DECL))
17506 add_pending_template (d);
17509 /* Tell the repository that D is available in this translation unit
17510 -- and see if it is supposed to be instantiated here. */
17511 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
17513 /* In a PCH file, despite the fact that the repository hasn't
17514 requested instantiation in the PCH it is still possible that
17515 an instantiation will be required in a file that includes the
17518 add_pending_template (d);
17519 /* Instantiate inline functions so that the inliner can do its
17520 job, even though we'll not be emitting a copy of this
17522 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
17526 need_push = !cfun || !global_bindings_p ();
17528 push_to_top_level ();
17530 /* Mark D as instantiated so that recursive calls to
17531 instantiate_decl do not try to instantiate it again. */
17532 DECL_TEMPLATE_INSTANTIATED (d) = 1;
17534 /* Regenerate the declaration in case the template has been modified
17535 by a subsequent redeclaration. */
17536 regenerate_decl_from_template (d, td);
17538 /* We already set the file and line above. Reset them now in case
17539 they changed as a result of calling regenerate_decl_from_template. */
17540 input_location = DECL_SOURCE_LOCATION (d);
17542 if (TREE_CODE (d) == VAR_DECL)
17545 bool const_init = false;
17547 /* Clear out DECL_RTL; whatever was there before may not be right
17548 since we've reset the type of the declaration. */
17549 SET_DECL_RTL (d, NULL);
17550 DECL_IN_AGGR_P (d) = 0;
17552 /* The initializer is placed in DECL_INITIAL by
17553 regenerate_decl_from_template so we don't need to
17554 push/pop_access_scope again here. Pull it out so that
17555 cp_finish_decl can process it. */
17556 init = DECL_INITIAL (d);
17557 DECL_INITIAL (d) = NULL_TREE;
17558 DECL_INITIALIZED_P (d) = 0;
17560 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
17561 initializer. That function will defer actual emission until
17562 we have a chance to determine linkage. */
17563 DECL_EXTERNAL (d) = 0;
17565 /* Enter the scope of D so that access-checking works correctly. */
17566 push_nested_class (DECL_CONTEXT (d));
17567 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17568 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
17569 pop_nested_class ();
17571 else if (TREE_CODE (d) == FUNCTION_DECL)
17573 htab_t saved_local_specializations;
17578 /* Save away the current list, in case we are instantiating one
17579 template from within the body of another. */
17580 saved_local_specializations = local_specializations;
17582 /* Set up the list of local specializations. */
17583 local_specializations = htab_create (37,
17584 hash_local_specialization,
17585 eq_local_specializations,
17588 /* Set up context. */
17589 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
17591 /* Create substitution entries for the parameters. */
17592 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
17593 tmpl_parm = DECL_ARGUMENTS (subst_decl);
17594 spec_parm = DECL_ARGUMENTS (d);
17595 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
17597 register_local_specialization (spec_parm, tmpl_parm);
17598 spec_parm = skip_artificial_parms_for (d, spec_parm);
17599 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
17601 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17603 register_local_specialization (spec_parm, tmpl_parm);
17604 tmpl_parm = DECL_CHAIN (tmpl_parm);
17605 spec_parm = DECL_CHAIN (spec_parm);
17607 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17609 /* Register the (value) argument pack as a specialization of
17610 TMPL_PARM, then move on. */
17611 tree argpack = make_fnparm_pack (spec_parm);
17612 register_local_specialization (argpack, tmpl_parm);
17613 tmpl_parm = DECL_CHAIN (tmpl_parm);
17614 spec_parm = NULL_TREE;
17616 gcc_assert (!spec_parm);
17618 /* Substitute into the body of the function. */
17619 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
17620 tf_warning_or_error, tmpl,
17621 /*integral_constant_expression_p=*/false);
17623 /* Set the current input_location to the end of the function
17624 so that finish_function knows where we are. */
17625 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17627 /* We don't need the local specializations any more. */
17628 htab_delete (local_specializations);
17629 local_specializations = saved_local_specializations;
17631 /* Finish the function. */
17632 d = finish_function (0);
17633 expand_or_defer_fn (d);
17636 /* We're not deferring instantiation any more. */
17637 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17640 pop_from_top_level ();
17643 input_location = saved_loc;
17644 pop_deferring_access_checks ();
17645 pop_tinst_level ();
17647 timevar_pop (TV_TEMPLATE_INST);
17652 /* Run through the list of templates that we wish we could
17653 instantiate, and instantiate any we can. RETRIES is the
17654 number of times we retry pending template instantiation. */
17657 instantiate_pending_templates (int retries)
17660 location_t saved_loc = input_location;
17662 /* Instantiating templates may trigger vtable generation. This in turn
17663 may require further template instantiations. We place a limit here
17664 to avoid infinite loop. */
17665 if (pending_templates && retries >= max_tinst_depth)
17667 tree decl = pending_templates->tinst->decl;
17669 error ("template instantiation depth exceeds maximum of %d"
17670 " instantiating %q+D, possibly from virtual table generation"
17671 " (use -ftemplate-depth= to increase the maximum)",
17672 max_tinst_depth, decl);
17673 if (TREE_CODE (decl) == FUNCTION_DECL)
17674 /* Pretend that we defined it. */
17675 DECL_INITIAL (decl) = error_mark_node;
17681 struct pending_template **t = &pending_templates;
17682 struct pending_template *last = NULL;
17686 tree instantiation = reopen_tinst_level ((*t)->tinst);
17687 bool complete = false;
17689 if (TYPE_P (instantiation))
17693 if (!COMPLETE_TYPE_P (instantiation))
17695 instantiate_class_template (instantiation);
17696 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17697 for (fn = TYPE_METHODS (instantiation);
17699 fn = TREE_CHAIN (fn))
17700 if (! DECL_ARTIFICIAL (fn))
17701 instantiate_decl (fn,
17703 /*expl_inst_class_mem_p=*/false);
17704 if (COMPLETE_TYPE_P (instantiation))
17708 complete = COMPLETE_TYPE_P (instantiation);
17712 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17713 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17716 = instantiate_decl (instantiation,
17718 /*expl_inst_class_mem_p=*/false);
17719 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17723 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17724 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17728 /* If INSTANTIATION has been instantiated, then we don't
17729 need to consider it again in the future. */
17737 current_tinst_level = NULL;
17739 last_pending_template = last;
17741 while (reconsider);
17743 input_location = saved_loc;
17746 /* Substitute ARGVEC into T, which is a list of initializers for
17747 either base class or a non-static data member. The TREE_PURPOSEs
17748 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17749 instantiate_decl. */
17752 tsubst_initializer_list (tree t, tree argvec)
17754 tree inits = NULL_TREE;
17756 for (; t; t = TREE_CHAIN (t))
17760 tree expanded_bases = NULL_TREE;
17761 tree expanded_arguments = NULL_TREE;
17764 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17769 /* Expand the base class expansion type into separate base
17771 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17772 tf_warning_or_error,
17774 if (expanded_bases == error_mark_node)
17777 /* We'll be building separate TREE_LISTs of arguments for
17779 len = TREE_VEC_LENGTH (expanded_bases);
17780 expanded_arguments = make_tree_vec (len);
17781 for (i = 0; i < len; i++)
17782 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17784 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17785 expand each argument in the TREE_VALUE of t. */
17786 expr = make_node (EXPR_PACK_EXPANSION);
17787 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17788 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17790 if (TREE_VALUE (t) == void_type_node)
17791 /* VOID_TYPE_NODE is used to indicate
17792 value-initialization. */
17794 for (i = 0; i < len; i++)
17795 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17799 /* Substitute parameter packs into each argument in the
17801 in_base_initializer = 1;
17802 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17804 tree expanded_exprs;
17806 /* Expand the argument. */
17807 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17809 = tsubst_pack_expansion (expr, argvec,
17810 tf_warning_or_error,
17812 if (expanded_exprs == error_mark_node)
17815 /* Prepend each of the expanded expressions to the
17816 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17817 for (i = 0; i < len; i++)
17819 TREE_VEC_ELT (expanded_arguments, i) =
17820 tree_cons (NULL_TREE,
17821 TREE_VEC_ELT (expanded_exprs, i),
17822 TREE_VEC_ELT (expanded_arguments, i));
17825 in_base_initializer = 0;
17827 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17828 since we built them backwards. */
17829 for (i = 0; i < len; i++)
17831 TREE_VEC_ELT (expanded_arguments, i) =
17832 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17837 for (i = 0; i < len; ++i)
17839 if (expanded_bases)
17841 decl = TREE_VEC_ELT (expanded_bases, i);
17842 decl = expand_member_init (decl);
17843 init = TREE_VEC_ELT (expanded_arguments, i);
17847 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17848 tf_warning_or_error, NULL_TREE);
17850 decl = expand_member_init (decl);
17851 if (decl && !DECL_P (decl))
17852 in_base_initializer = 1;
17854 init = TREE_VALUE (t);
17855 if (init != void_type_node)
17856 init = tsubst_expr (init, argvec,
17857 tf_warning_or_error, NULL_TREE,
17858 /*integral_constant_expression_p=*/false);
17859 in_base_initializer = 0;
17864 init = build_tree_list (decl, init);
17865 TREE_CHAIN (init) = inits;
17873 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17876 set_current_access_from_decl (tree decl)
17878 if (TREE_PRIVATE (decl))
17879 current_access_specifier = access_private_node;
17880 else if (TREE_PROTECTED (decl))
17881 current_access_specifier = access_protected_node;
17883 current_access_specifier = access_public_node;
17886 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17887 is the instantiation (which should have been created with
17888 start_enum) and ARGS are the template arguments to use. */
17891 tsubst_enum (tree tag, tree newtag, tree args)
17895 if (SCOPED_ENUM_P (newtag))
17896 begin_scope (sk_scoped_enum, newtag);
17898 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17903 decl = TREE_VALUE (e);
17904 /* Note that in a template enum, the TREE_VALUE is the
17905 CONST_DECL, not the corresponding INTEGER_CST. */
17906 value = tsubst_expr (DECL_INITIAL (decl),
17907 args, tf_warning_or_error, NULL_TREE,
17908 /*integral_constant_expression_p=*/true);
17910 /* Give this enumeration constant the correct access. */
17911 set_current_access_from_decl (decl);
17913 /* Actually build the enumerator itself. */
17915 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
17918 if (SCOPED_ENUM_P (newtag))
17921 finish_enum_value_list (newtag);
17922 finish_enum (newtag);
17924 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17925 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17928 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17929 its type -- but without substituting the innermost set of template
17930 arguments. So, innermost set of template parameters will appear in
17934 get_mostly_instantiated_function_type (tree decl)
17942 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17943 targs = DECL_TI_ARGS (decl);
17944 tparms = DECL_TEMPLATE_PARMS (tmpl);
17945 parm_depth = TMPL_PARMS_DEPTH (tparms);
17947 /* There should be as many levels of arguments as there are levels
17949 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
17951 fn_type = TREE_TYPE (tmpl);
17953 if (parm_depth == 1)
17954 /* No substitution is necessary. */
17958 int i, save_access_control;
17961 /* Replace the innermost level of the TARGS with NULL_TREEs to
17962 let tsubst know not to substitute for those parameters. */
17963 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
17964 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
17965 SET_TMPL_ARGS_LEVEL (partial_args, i,
17966 TMPL_ARGS_LEVEL (targs, i));
17967 SET_TMPL_ARGS_LEVEL (partial_args,
17968 TMPL_ARGS_DEPTH (targs),
17969 make_tree_vec (DECL_NTPARMS (tmpl)));
17971 /* Disable access control as this function is used only during
17973 save_access_control = flag_access_control;
17974 flag_access_control = 0;
17976 ++processing_template_decl;
17977 /* Now, do the (partial) substitution to figure out the
17978 appropriate function type. */
17979 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
17980 --processing_template_decl;
17982 /* Substitute into the template parameters to obtain the real
17983 innermost set of parameters. This step is important if the
17984 innermost set of template parameters contains value
17985 parameters whose types depend on outer template parameters. */
17986 TREE_VEC_LENGTH (partial_args)--;
17987 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
17989 flag_access_control = save_access_control;
17995 /* Return truthvalue if we're processing a template different from
17996 the last one involved in diagnostics. */
17998 problematic_instantiation_changed (void)
18000 return last_template_error_tick != tinst_level_tick;
18003 /* Remember current template involved in diagnostics. */
18005 record_last_problematic_instantiation (void)
18007 last_template_error_tick = tinst_level_tick;
18010 struct tinst_level *
18011 current_instantiation (void)
18013 return current_tinst_level;
18016 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18017 type. Return zero for ok, nonzero for disallowed. Issue error and
18018 warning messages under control of COMPLAIN. */
18021 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18023 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18025 else if (POINTER_TYPE_P (type))
18027 else if (TYPE_PTR_TO_MEMBER_P (type))
18029 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18031 else if (TREE_CODE (type) == TYPENAME_TYPE)
18034 if (complain & tf_error)
18035 error ("%q#T is not a valid type for a template constant parameter", type);
18039 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18040 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18043 dependent_type_p_r (tree type)
18049 A type is dependent if it is:
18051 -- a template parameter. Template template parameters are types
18052 for us (since TYPE_P holds true for them) so we handle
18054 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18055 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18057 /* -- a qualified-id with a nested-name-specifier which contains a
18058 class-name that names a dependent type or whose unqualified-id
18059 names a dependent type. */
18060 if (TREE_CODE (type) == TYPENAME_TYPE)
18062 /* -- a cv-qualified type where the cv-unqualified type is
18064 type = TYPE_MAIN_VARIANT (type);
18065 /* -- a compound type constructed from any dependent type. */
18066 if (TYPE_PTR_TO_MEMBER_P (type))
18067 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18068 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18070 else if (TREE_CODE (type) == POINTER_TYPE
18071 || TREE_CODE (type) == REFERENCE_TYPE)
18072 return dependent_type_p (TREE_TYPE (type));
18073 else if (TREE_CODE (type) == FUNCTION_TYPE
18074 || TREE_CODE (type) == METHOD_TYPE)
18078 if (dependent_type_p (TREE_TYPE (type)))
18080 for (arg_type = TYPE_ARG_TYPES (type);
18082 arg_type = TREE_CHAIN (arg_type))
18083 if (dependent_type_p (TREE_VALUE (arg_type)))
18087 /* -- an array type constructed from any dependent type or whose
18088 size is specified by a constant expression that is
18091 We checked for type- and value-dependence of the bounds in
18092 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18093 if (TREE_CODE (type) == ARRAY_TYPE)
18095 if (TYPE_DOMAIN (type)
18096 && dependent_type_p (TYPE_DOMAIN (type)))
18098 return dependent_type_p (TREE_TYPE (type));
18101 /* -- a template-id in which either the template name is a template
18103 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18105 /* ... or any of the template arguments is a dependent type or
18106 an expression that is type-dependent or value-dependent. */
18107 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18108 && (any_dependent_template_arguments_p
18109 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18112 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18113 dependent; if the argument of the `typeof' expression is not
18114 type-dependent, then it should already been have resolved. */
18115 if (TREE_CODE (type) == TYPEOF_TYPE
18116 || TREE_CODE (type) == DECLTYPE_TYPE
18117 || TREE_CODE (type) == UNDERLYING_TYPE)
18120 /* A template argument pack is dependent if any of its packed
18122 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18124 tree args = ARGUMENT_PACK_ARGS (type);
18125 int i, len = TREE_VEC_LENGTH (args);
18126 for (i = 0; i < len; ++i)
18127 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18131 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18132 be template parameters. */
18133 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18136 /* The standard does not specifically mention types that are local
18137 to template functions or local classes, but they should be
18138 considered dependent too. For example:
18140 template <int I> void f() {
18145 The size of `E' cannot be known until the value of `I' has been
18146 determined. Therefore, `E' must be considered dependent. */
18147 scope = TYPE_CONTEXT (type);
18148 if (scope && TYPE_P (scope))
18149 return dependent_type_p (scope);
18150 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
18151 return type_dependent_expression_p (scope);
18153 /* Other types are non-dependent. */
18157 /* Returns TRUE if TYPE is dependent, in the sense of
18158 [temp.dep.type]. Note that a NULL type is considered dependent. */
18161 dependent_type_p (tree type)
18163 /* If there are no template parameters in scope, then there can't be
18164 any dependent types. */
18165 if (!processing_template_decl)
18167 /* If we are not processing a template, then nobody should be
18168 providing us with a dependent type. */
18170 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18174 /* If the type is NULL, we have not computed a type for the entity
18175 in question; in that case, the type is dependent. */
18179 /* Erroneous types can be considered non-dependent. */
18180 if (type == error_mark_node)
18183 /* If we have not already computed the appropriate value for TYPE,
18185 if (!TYPE_DEPENDENT_P_VALID (type))
18187 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18188 TYPE_DEPENDENT_P_VALID (type) = 1;
18191 return TYPE_DEPENDENT_P (type);
18194 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18195 lookup. In other words, a dependent type that is not the current
18199 dependent_scope_p (tree scope)
18201 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18202 && !currently_open_class (scope));
18205 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18206 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18209 /* Note that this predicate is not appropriate for general expressions;
18210 only constant expressions (that satisfy potential_constant_expression)
18211 can be tested for value dependence.
18213 We should really also have a predicate for "instantiation-dependent".
18215 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18216 (what about instantiation-dependent constant-expressions?)
18217 is_late_template_attribute: defer if instantiation-dependent.
18218 compute_array_index_type: proceed if constant and not t- or v-dependent
18219 if instantiation-dependent, need to remember full expression
18220 uses_template_parms: FIXME - need to audit callers
18221 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18222 dependent_type_p [array_type]: dependent if index type is dependent
18224 static_assert - instantiation-dependent */
18227 value_dependent_expression_p (tree expression)
18229 if (!processing_template_decl)
18232 /* A name declared with a dependent type. */
18233 if (DECL_P (expression) && type_dependent_expression_p (expression))
18236 switch (TREE_CODE (expression))
18238 case IDENTIFIER_NODE:
18239 /* A name that has not been looked up -- must be dependent. */
18242 case TEMPLATE_PARM_INDEX:
18243 /* A non-type template parm. */
18247 /* A non-type template parm. */
18248 if (DECL_TEMPLATE_PARM_P (expression))
18250 return value_dependent_expression_p (DECL_INITIAL (expression));
18253 /* A constant with literal type and is initialized
18254 with an expression that is value-dependent. */
18255 if (DECL_INITIAL (expression)
18256 && decl_constant_var_p (expression)
18257 && value_dependent_expression_p (DECL_INITIAL (expression)))
18261 case DYNAMIC_CAST_EXPR:
18262 case STATIC_CAST_EXPR:
18263 case CONST_CAST_EXPR:
18264 case REINTERPRET_CAST_EXPR:
18266 /* These expressions are value-dependent if the type to which
18267 the cast occurs is dependent or the expression being casted
18268 is value-dependent. */
18270 tree type = TREE_TYPE (expression);
18272 if (dependent_type_p (type))
18275 /* A functional cast has a list of operands. */
18276 expression = TREE_OPERAND (expression, 0);
18279 /* If there are no operands, it must be an expression such
18280 as "int()". This should not happen for aggregate types
18281 because it would form non-constant expressions. */
18282 gcc_assert (cxx_dialect >= cxx0x
18283 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18288 if (TREE_CODE (expression) == TREE_LIST)
18289 return any_value_dependent_elements_p (expression);
18291 return value_dependent_expression_p (expression);
18297 /* A `sizeof' expression is value-dependent if the operand is
18298 type-dependent or is a pack expansion. */
18299 expression = TREE_OPERAND (expression, 0);
18300 if (PACK_EXPANSION_P (expression))
18302 else if (TYPE_P (expression))
18303 return dependent_type_p (expression);
18304 return type_dependent_expression_p (expression);
18306 case AT_ENCODE_EXPR:
18307 /* An 'encode' expression is value-dependent if the operand is
18309 expression = TREE_OPERAND (expression, 0);
18310 return dependent_type_p (expression);
18312 case NOEXCEPT_EXPR:
18313 expression = TREE_OPERAND (expression, 0);
18314 return type_dependent_expression_p (expression);
18318 tree name = TREE_OPERAND (expression, 1);
18319 return value_dependent_expression_p (name);
18322 case COMPONENT_REF:
18323 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18324 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18326 case NONTYPE_ARGUMENT_PACK:
18327 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18328 is value-dependent. */
18330 tree values = ARGUMENT_PACK_ARGS (expression);
18331 int i, len = TREE_VEC_LENGTH (values);
18333 for (i = 0; i < len; ++i)
18334 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
18342 tree type2 = TRAIT_EXPR_TYPE2 (expression);
18343 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
18344 || (type2 ? dependent_type_p (type2) : false));
18348 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18349 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
18352 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18353 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
18357 tree op = TREE_OPERAND (expression, 0);
18358 return (value_dependent_expression_p (op)
18359 || has_value_dependent_address (op));
18364 tree fn = get_callee_fndecl (expression);
18366 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
18368 nargs = call_expr_nargs (expression);
18369 for (i = 0; i < nargs; ++i)
18371 tree op = CALL_EXPR_ARG (expression, i);
18372 /* In a call to a constexpr member function, look through the
18373 implicit ADDR_EXPR on the object argument so that it doesn't
18374 cause the call to be considered value-dependent. We also
18375 look through it in potential_constant_expression. */
18376 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
18377 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
18378 && TREE_CODE (op) == ADDR_EXPR)
18379 op = TREE_OPERAND (op, 0);
18380 if (value_dependent_expression_p (op))
18386 case TEMPLATE_ID_EXPR:
18387 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
18389 return type_dependent_expression_p (expression);
18395 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
18396 if (value_dependent_expression_p (val))
18402 /* A constant expression is value-dependent if any subexpression is
18403 value-dependent. */
18404 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
18406 case tcc_reference:
18408 case tcc_comparison:
18410 case tcc_expression:
18413 int i, len = cp_tree_operand_length (expression);
18415 for (i = 0; i < len; i++)
18417 tree t = TREE_OPERAND (expression, i);
18419 /* In some cases, some of the operands may be missing.l
18420 (For example, in the case of PREDECREMENT_EXPR, the
18421 amount to increment by may be missing.) That doesn't
18422 make the expression dependent. */
18423 if (t && value_dependent_expression_p (t))
18434 /* The expression is not value-dependent. */
18438 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
18439 [temp.dep.expr]. Note that an expression with no type is
18440 considered dependent. Other parts of the compiler arrange for an
18441 expression with type-dependent subexpressions to have no type, so
18442 this function doesn't have to be fully recursive. */
18445 type_dependent_expression_p (tree expression)
18447 if (!processing_template_decl)
18450 if (expression == error_mark_node)
18453 /* An unresolved name is always dependent. */
18454 if (TREE_CODE (expression) == IDENTIFIER_NODE
18455 || TREE_CODE (expression) == USING_DECL)
18458 /* Some expression forms are never type-dependent. */
18459 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
18460 || TREE_CODE (expression) == SIZEOF_EXPR
18461 || TREE_CODE (expression) == ALIGNOF_EXPR
18462 || TREE_CODE (expression) == AT_ENCODE_EXPR
18463 || TREE_CODE (expression) == NOEXCEPT_EXPR
18464 || TREE_CODE (expression) == TRAIT_EXPR
18465 || TREE_CODE (expression) == TYPEID_EXPR
18466 || TREE_CODE (expression) == DELETE_EXPR
18467 || TREE_CODE (expression) == VEC_DELETE_EXPR
18468 || TREE_CODE (expression) == THROW_EXPR)
18471 /* The types of these expressions depends only on the type to which
18472 the cast occurs. */
18473 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
18474 || TREE_CODE (expression) == STATIC_CAST_EXPR
18475 || TREE_CODE (expression) == CONST_CAST_EXPR
18476 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
18477 || TREE_CODE (expression) == CAST_EXPR)
18478 return dependent_type_p (TREE_TYPE (expression));
18480 /* The types of these expressions depends only on the type created
18481 by the expression. */
18482 if (TREE_CODE (expression) == NEW_EXPR
18483 || TREE_CODE (expression) == VEC_NEW_EXPR)
18485 /* For NEW_EXPR tree nodes created inside a template, either
18486 the object type itself or a TREE_LIST may appear as the
18488 tree type = TREE_OPERAND (expression, 1);
18489 if (TREE_CODE (type) == TREE_LIST)
18490 /* This is an array type. We need to check array dimensions
18492 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
18493 || value_dependent_expression_p
18494 (TREE_OPERAND (TREE_VALUE (type), 1));
18496 return dependent_type_p (type);
18499 if (TREE_CODE (expression) == SCOPE_REF)
18501 tree scope = TREE_OPERAND (expression, 0);
18502 tree name = TREE_OPERAND (expression, 1);
18504 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
18505 contains an identifier associated by name lookup with one or more
18506 declarations declared with a dependent type, or...a
18507 nested-name-specifier or qualified-id that names a member of an
18508 unknown specialization. */
18509 return (type_dependent_expression_p (name)
18510 || dependent_scope_p (scope));
18513 if (TREE_CODE (expression) == FUNCTION_DECL
18514 && DECL_LANG_SPECIFIC (expression)
18515 && DECL_TEMPLATE_INFO (expression)
18516 && (any_dependent_template_arguments_p
18517 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
18520 if (TREE_CODE (expression) == TEMPLATE_DECL
18521 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
18524 if (TREE_CODE (expression) == STMT_EXPR)
18525 expression = stmt_expr_value_expr (expression);
18527 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
18532 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
18534 if (type_dependent_expression_p (elt))
18540 /* A static data member of the current instantiation with incomplete
18541 array type is type-dependent, as the definition and specializations
18542 can have different bounds. */
18543 if (TREE_CODE (expression) == VAR_DECL
18544 && DECL_CLASS_SCOPE_P (expression)
18545 && dependent_type_p (DECL_CONTEXT (expression))
18546 && VAR_HAD_UNKNOWN_BOUND (expression))
18549 if (TREE_TYPE (expression) == unknown_type_node)
18551 if (TREE_CODE (expression) == ADDR_EXPR)
18552 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
18553 if (TREE_CODE (expression) == COMPONENT_REF
18554 || TREE_CODE (expression) == OFFSET_REF)
18556 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
18558 expression = TREE_OPERAND (expression, 1);
18559 if (TREE_CODE (expression) == IDENTIFIER_NODE)
18562 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
18563 if (TREE_CODE (expression) == SCOPE_REF)
18566 if (TREE_CODE (expression) == BASELINK)
18567 expression = BASELINK_FUNCTIONS (expression);
18569 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
18571 if (any_dependent_template_arguments_p
18572 (TREE_OPERAND (expression, 1)))
18574 expression = TREE_OPERAND (expression, 0);
18576 gcc_assert (TREE_CODE (expression) == OVERLOAD
18577 || TREE_CODE (expression) == FUNCTION_DECL);
18581 if (type_dependent_expression_p (OVL_CURRENT (expression)))
18583 expression = OVL_NEXT (expression);
18588 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
18590 return (dependent_type_p (TREE_TYPE (expression)));
18593 /* Like type_dependent_expression_p, but it also works while not processing
18594 a template definition, i.e. during substitution or mangling. */
18597 type_dependent_expression_p_push (tree expr)
18600 ++processing_template_decl;
18601 b = type_dependent_expression_p (expr);
18602 --processing_template_decl;
18606 /* Returns TRUE if ARGS contains a type-dependent expression. */
18609 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
18614 FOR_EACH_VEC_ELT (tree, args, i, arg)
18616 if (type_dependent_expression_p (arg))
18622 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18623 expressions) contains any type-dependent expressions. */
18626 any_type_dependent_elements_p (const_tree list)
18628 for (; list; list = TREE_CHAIN (list))
18629 if (value_dependent_expression_p (TREE_VALUE (list)))
18635 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18636 expressions) contains any value-dependent expressions. */
18639 any_value_dependent_elements_p (const_tree list)
18641 for (; list; list = TREE_CHAIN (list))
18642 if (value_dependent_expression_p (TREE_VALUE (list)))
18648 /* Returns TRUE if the ARG (a template argument) is dependent. */
18651 dependent_template_arg_p (tree arg)
18653 if (!processing_template_decl)
18656 /* Assume a template argument that was wrongly written by the user
18657 is dependent. This is consistent with what
18658 any_dependent_template_arguments_p [that calls this function]
18660 if (arg == error_mark_node)
18663 if (TREE_CODE (arg) == TEMPLATE_DECL
18664 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18665 return dependent_template_p (arg);
18666 else if (ARGUMENT_PACK_P (arg))
18668 tree args = ARGUMENT_PACK_ARGS (arg);
18669 int i, len = TREE_VEC_LENGTH (args);
18670 for (i = 0; i < len; ++i)
18672 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18678 else if (TYPE_P (arg))
18679 return dependent_type_p (arg);
18681 return (type_dependent_expression_p (arg)
18682 || value_dependent_expression_p (arg));
18685 /* Returns true if ARGS (a collection of template arguments) contains
18686 any types that require structural equality testing. */
18689 any_template_arguments_need_structural_equality_p (tree args)
18696 if (args == error_mark_node)
18699 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18701 tree level = TMPL_ARGS_LEVEL (args, i + 1);
18702 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18704 tree arg = TREE_VEC_ELT (level, j);
18705 tree packed_args = NULL_TREE;
18708 if (ARGUMENT_PACK_P (arg))
18710 /* Look inside the argument pack. */
18711 packed_args = ARGUMENT_PACK_ARGS (arg);
18712 len = TREE_VEC_LENGTH (packed_args);
18715 for (k = 0; k < len; ++k)
18718 arg = TREE_VEC_ELT (packed_args, k);
18720 if (error_operand_p (arg))
18722 else if (TREE_CODE (arg) == TEMPLATE_DECL
18723 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18725 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18727 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18728 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18737 /* Returns true if ARGS (a collection of template arguments) contains
18738 any dependent arguments. */
18741 any_dependent_template_arguments_p (const_tree args)
18748 if (args == error_mark_node)
18751 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18753 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18754 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18755 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18762 /* Returns TRUE if the template TMPL is dependent. */
18765 dependent_template_p (tree tmpl)
18767 if (TREE_CODE (tmpl) == OVERLOAD)
18771 if (dependent_template_p (OVL_CURRENT (tmpl)))
18773 tmpl = OVL_NEXT (tmpl);
18778 /* Template template parameters are dependent. */
18779 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18780 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18782 /* So are names that have not been looked up. */
18783 if (TREE_CODE (tmpl) == SCOPE_REF
18784 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18786 /* So are member templates of dependent classes. */
18787 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18788 return dependent_type_p (DECL_CONTEXT (tmpl));
18792 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18795 dependent_template_id_p (tree tmpl, tree args)
18797 return (dependent_template_p (tmpl)
18798 || any_dependent_template_arguments_p (args));
18801 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18805 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18809 if (!processing_template_decl)
18812 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18814 tree decl = TREE_VEC_ELT (declv, i);
18815 tree init = TREE_VEC_ELT (initv, i);
18816 tree cond = TREE_VEC_ELT (condv, i);
18817 tree incr = TREE_VEC_ELT (incrv, i);
18819 if (type_dependent_expression_p (decl))
18822 if (init && type_dependent_expression_p (init))
18825 if (type_dependent_expression_p (cond))
18828 if (COMPARISON_CLASS_P (cond)
18829 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18830 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18833 if (TREE_CODE (incr) == MODOP_EXPR)
18835 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18836 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18839 else if (type_dependent_expression_p (incr))
18841 else if (TREE_CODE (incr) == MODIFY_EXPR)
18843 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18845 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
18847 tree t = TREE_OPERAND (incr, 1);
18848 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
18849 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
18858 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
18859 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
18860 no such TYPE can be found. Note that this function peers inside
18861 uninstantiated templates and therefore should be used only in
18862 extremely limited situations. ONLY_CURRENT_P restricts this
18863 peering to the currently open classes hierarchy (which is required
18864 when comparing types). */
18867 resolve_typename_type (tree type, bool only_current_p)
18876 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
18878 scope = TYPE_CONTEXT (type);
18879 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
18880 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
18881 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
18882 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
18883 identifier of the TYPENAME_TYPE anymore.
18884 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
18885 TYPENAME_TYPE instead, we avoid messing up with a possible
18886 typedef variant case. */
18887 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
18889 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
18890 it first before we can figure out what NAME refers to. */
18891 if (TREE_CODE (scope) == TYPENAME_TYPE)
18892 scope = resolve_typename_type (scope, only_current_p);
18893 /* If we don't know what SCOPE refers to, then we cannot resolve the
18895 if (TREE_CODE (scope) == TYPENAME_TYPE)
18897 /* If the SCOPE is a template type parameter, we have no way of
18898 resolving the name. */
18899 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
18901 /* If the SCOPE is not the current instantiation, there's no reason
18902 to look inside it. */
18903 if (only_current_p && !currently_open_class (scope))
18905 /* If this is a typedef, we don't want to look inside (c++/11987). */
18906 if (typedef_variant_p (type))
18908 /* If SCOPE isn't the template itself, it will not have a valid
18909 TYPE_FIELDS list. */
18910 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
18911 /* scope is either the template itself or a compatible instantiation
18912 like X<T>, so look up the name in the original template. */
18913 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
18915 /* scope is a partial instantiation, so we can't do the lookup or we
18916 will lose the template arguments. */
18918 /* Enter the SCOPE so that name lookup will be resolved as if we
18919 were in the class definition. In particular, SCOPE will no
18920 longer be considered a dependent type. */
18921 pushed_scope = push_scope (scope);
18922 /* Look up the declaration. */
18923 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
18925 result = NULL_TREE;
18927 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
18928 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
18931 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
18932 && TREE_CODE (decl) == TYPE_DECL)
18934 result = TREE_TYPE (decl);
18935 if (result == error_mark_node)
18936 result = NULL_TREE;
18938 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
18939 && DECL_CLASS_TEMPLATE_P (decl))
18943 /* Obtain the template and the arguments. */
18944 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
18945 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
18946 /* Instantiate the template. */
18947 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
18948 /*entering_scope=*/0,
18949 tf_error | tf_user);
18950 if (result == error_mark_node)
18951 result = NULL_TREE;
18954 /* Leave the SCOPE. */
18956 pop_scope (pushed_scope);
18958 /* If we failed to resolve it, return the original typename. */
18962 /* If lookup found a typename type, resolve that too. */
18963 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
18965 /* Ill-formed programs can cause infinite recursion here, so we
18966 must catch that. */
18967 TYPENAME_IS_RESOLVING_P (type) = 1;
18968 result = resolve_typename_type (result, only_current_p);
18969 TYPENAME_IS_RESOLVING_P (type) = 0;
18972 /* Qualify the resulting type. */
18973 quals = cp_type_quals (type);
18975 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
18980 /* EXPR is an expression which is not type-dependent. Return a proxy
18981 for EXPR that can be used to compute the types of larger
18982 expressions containing EXPR. */
18985 build_non_dependent_expr (tree expr)
18989 #ifdef ENABLE_CHECKING
18990 /* Try to get a constant value for all non-type-dependent expressions in
18991 order to expose bugs in *_dependent_expression_p and constexpr. */
18992 if (cxx_dialect >= cxx0x)
18993 maybe_constant_value (fold_non_dependent_expr (expr));
18996 /* Preserve OVERLOADs; the functions must be available to resolve
18999 if (TREE_CODE (inner_expr) == STMT_EXPR)
19000 inner_expr = stmt_expr_value_expr (inner_expr);
19001 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19002 inner_expr = TREE_OPERAND (inner_expr, 0);
19003 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19004 inner_expr = TREE_OPERAND (inner_expr, 1);
19005 if (is_overloaded_fn (inner_expr)
19006 || TREE_CODE (inner_expr) == OFFSET_REF)
19008 /* There is no need to return a proxy for a variable. */
19009 if (TREE_CODE (expr) == VAR_DECL)
19011 /* Preserve string constants; conversions from string constants to
19012 "char *" are allowed, even though normally a "const char *"
19013 cannot be used to initialize a "char *". */
19014 if (TREE_CODE (expr) == STRING_CST)
19016 /* Preserve arithmetic constants, as an optimization -- there is no
19017 reason to create a new node. */
19018 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19020 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19021 There is at least one place where we want to know that a
19022 particular expression is a throw-expression: when checking a ?:
19023 expression, there are special rules if the second or third
19024 argument is a throw-expression. */
19025 if (TREE_CODE (expr) == THROW_EXPR)
19028 if (TREE_CODE (expr) == COND_EXPR)
19029 return build3 (COND_EXPR,
19031 TREE_OPERAND (expr, 0),
19032 (TREE_OPERAND (expr, 1)
19033 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19034 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19035 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19036 if (TREE_CODE (expr) == COMPOUND_EXPR
19037 && !COMPOUND_EXPR_OVERLOADED (expr))
19038 return build2 (COMPOUND_EXPR,
19040 TREE_OPERAND (expr, 0),
19041 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19043 /* Keep dereferences outside the NON_DEPENDENT_EXPR so lvalue_kind
19044 doesn't need to look inside. */
19045 if (REFERENCE_REF_P (expr))
19046 return convert_from_reference (build_non_dependent_expr
19047 (TREE_OPERAND (expr, 0)));
19049 /* If the type is unknown, it can't really be non-dependent */
19050 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19052 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19053 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19056 /* ARGS is a vector of expressions as arguments to a function call.
19057 Replace the arguments with equivalent non-dependent expressions.
19058 This modifies ARGS in place. */
19061 make_args_non_dependent (VEC(tree,gc) *args)
19066 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19068 tree newarg = build_non_dependent_expr (arg);
19070 VEC_replace (tree, args, ix, newarg);
19074 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19075 with a level one deeper than the actual template parms. */
19080 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19081 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19082 TYPE_DECL, get_identifier ("auto"), au);
19083 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19084 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19085 (0, processing_template_decl + 1, processing_template_decl + 1,
19086 0, TYPE_NAME (au), NULL_TREE);
19087 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19088 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19089 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19094 /* Given type ARG, return std::initializer_list<ARG>. */
19099 tree std_init_list = namespace_binding
19100 (get_identifier ("initializer_list"), std_node);
19102 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19104 error ("deducing from brace-enclosed initializer list requires "
19105 "#include <initializer_list>");
19106 return error_mark_node;
19108 argvec = make_tree_vec (1);
19109 TREE_VEC_ELT (argvec, 0) = arg;
19110 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19111 NULL_TREE, 0, tf_warning_or_error);
19114 /* Replace auto in TYPE with std::initializer_list<auto>. */
19117 listify_autos (tree type, tree auto_node)
19119 tree init_auto = listify (auto_node);
19120 tree argvec = make_tree_vec (1);
19121 TREE_VEC_ELT (argvec, 0) = init_auto;
19122 if (processing_template_decl)
19123 argvec = add_to_template_args (current_template_args (), argvec);
19124 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19127 /* walk_tree helper for do_auto_deduction. */
19130 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19133 /* Is this a variable with the type we're looking for? */
19135 && TREE_TYPE (*tp) == type)
19141 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19142 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19145 do_auto_deduction (tree type, tree init, tree auto_node)
19147 tree parms, tparms, targs;
19152 /* The name of the object being declared shall not appear in the
19153 initializer expression. */
19154 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19157 error ("variable %q#D with %<auto%> type used in its own "
19158 "initializer", decl);
19159 return error_mark_node;
19162 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19163 with either a new invented type template parameter U or, if the
19164 initializer is a braced-init-list (8.5.4), with
19165 std::initializer_list<U>. */
19166 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19167 type = listify_autos (type, auto_node);
19169 init = resolve_nondeduced_context (init);
19171 parms = build_tree_list (NULL_TREE, type);
19173 tparms = make_tree_vec (1);
19174 targs = make_tree_vec (1);
19175 TREE_VEC_ELT (tparms, 0)
19176 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19177 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19178 DEDUCE_CALL, LOOKUP_NORMAL);
19181 if (type && type != error_mark_node)
19182 /* If type is error_mark_node a diagnostic must have been
19183 emitted by now. Also, having a mention to '<type error>'
19184 in the diagnostic is not really useful to the user. */
19185 error ("unable to deduce %qT from %qE", type, init);
19186 return error_mark_node;
19189 /* If the list of declarators contains more than one declarator, the type
19190 of each declared variable is determined as described above. If the
19191 type deduced for the template parameter U is not the same in each
19192 deduction, the program is ill-formed. */
19193 if (TREE_TYPE (auto_node)
19194 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19196 error ("inconsistent deduction for %qT: %qT and then %qT",
19197 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19198 return error_mark_node;
19200 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19202 if (processing_template_decl)
19203 targs = add_to_template_args (current_template_args (), targs);
19204 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19207 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19211 splice_late_return_type (tree type, tree late_return_type)
19215 if (late_return_type == NULL_TREE)
19217 argvec = make_tree_vec (1);
19218 TREE_VEC_ELT (argvec, 0) = late_return_type;
19219 if (processing_template_decl)
19220 argvec = add_to_template_args (current_template_args (), argvec);
19221 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19224 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19227 is_auto (const_tree type)
19229 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19230 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
19236 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
19237 appear as a type-specifier for the declaration in question, we don't
19238 have to look through the whole type. */
19241 type_uses_auto (tree type)
19243 enum tree_code code;
19244 if (is_auto (type))
19247 code = TREE_CODE (type);
19249 if (code == POINTER_TYPE || code == REFERENCE_TYPE
19250 || code == OFFSET_TYPE || code == FUNCTION_TYPE
19251 || code == METHOD_TYPE || code == ARRAY_TYPE)
19252 return type_uses_auto (TREE_TYPE (type));
19254 if (TYPE_PTRMEMFUNC_P (type))
19255 return type_uses_auto (TREE_TYPE (TREE_TYPE
19256 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
19261 /* For a given template T, return the vector of typedefs referenced
19262 in T for which access check is needed at T instantiation time.
19263 T is either a FUNCTION_DECL or a RECORD_TYPE.
19264 Those typedefs were added to T by the function
19265 append_type_to_template_for_access_check. */
19267 VEC(qualified_typedef_usage_t,gc)*
19268 get_types_needing_access_check (tree t)
19271 VEC(qualified_typedef_usage_t,gc) *result = NULL;
19273 if (!t || t == error_mark_node)
19276 if (!(ti = get_template_info (t)))
19279 if (CLASS_TYPE_P (t)
19280 || TREE_CODE (t) == FUNCTION_DECL)
19282 if (!TI_TEMPLATE (ti))
19285 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19291 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19292 tied to T. That list of typedefs will be access checked at
19293 T instantiation time.
19294 T is either a FUNCTION_DECL or a RECORD_TYPE.
19295 TYPE_DECL is a TYPE_DECL node representing a typedef.
19296 SCOPE is the scope through which TYPE_DECL is accessed.
19297 LOCATION is the location of the usage point of TYPE_DECL.
19299 This function is a subroutine of
19300 append_type_to_template_for_access_check. */
19303 append_type_to_template_for_access_check_1 (tree t,
19306 location_t location)
19308 qualified_typedef_usage_t typedef_usage;
19311 if (!t || t == error_mark_node)
19314 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19315 || CLASS_TYPE_P (t))
19317 && TREE_CODE (type_decl) == TYPE_DECL
19320 if (!(ti = get_template_info (t)))
19323 gcc_assert (TI_TEMPLATE (ti));
19325 typedef_usage.typedef_decl = type_decl;
19326 typedef_usage.context = scope;
19327 typedef_usage.locus = location;
19329 VEC_safe_push (qualified_typedef_usage_t, gc,
19330 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
19334 /* Append TYPE_DECL to the template TEMPL.
19335 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
19336 At TEMPL instanciation time, TYPE_DECL will be checked to see
19337 if it can be accessed through SCOPE.
19338 LOCATION is the location of the usage point of TYPE_DECL.
19340 e.g. consider the following code snippet:
19347 template<class U> struct S
19349 C::myint mi; // <-- usage point of the typedef C::myint
19354 At S<char> instantiation time, we need to check the access of C::myint
19355 In other words, we need to check the access of the myint typedef through
19356 the C scope. For that purpose, this function will add the myint typedef
19357 and the scope C through which its being accessed to a list of typedefs
19358 tied to the template S. That list will be walked at template instantiation
19359 time and access check performed on each typedefs it contains.
19360 Note that this particular code snippet should yield an error because
19361 myint is private to C. */
19364 append_type_to_template_for_access_check (tree templ,
19367 location_t location)
19369 qualified_typedef_usage_t *iter;
19372 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
19374 /* Make sure we don't append the type to the template twice. */
19375 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
19376 get_types_needing_access_check (templ),
19378 if (iter->typedef_decl == type_decl && scope == iter->context)
19381 append_type_to_template_for_access_check_1 (templ, type_decl,
19385 /* Set up the hash tables for template instantiations. */
19388 init_template_processing (void)
19390 decl_specializations = htab_create_ggc (37,
19391 hash_specialization,
19392 eq_specializations,
19394 type_specializations = htab_create_ggc (37,
19395 hash_specialization,
19396 eq_specializations,
19400 /* Print stats about the template hash tables for -fstats. */
19403 print_template_statistics (void)
19405 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
19406 "%f collisions\n", (long) htab_size (decl_specializations),
19407 (long) htab_elements (decl_specializations),
19408 htab_collisions (decl_specializations));
19409 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
19410 "%f collisions\n", (long) htab_size (type_specializations),
19411 (long) htab_elements (type_specializations),
19412 htab_collisions (type_specializations));
19413 if (current_deduction_htab)
19414 fprintf (stderr, "current_deduction_htab: size %ld, %ld elements, "
19415 "%f collisions\n", (long) htab_size (current_deduction_htab),
19416 (long) htab_elements (current_deduction_htab),
19417 htab_collisions (current_deduction_htab));
19420 #include "gt-cp-pt.h"