1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
45 #include "tree-iterator.h"
48 /* The type of functions taking a tree, and some additional data, and
50 typedef int (*tree_fn_t) (tree, void*);
52 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
53 instantiations have been deferred, either because their definitions
54 were not yet available, or because we were putting off doing the work. */
55 struct GTY (()) pending_template {
56 struct pending_template *next;
57 struct tinst_level *tinst;
60 static GTY(()) struct pending_template *pending_templates;
61 static GTY(()) struct pending_template *last_pending_template;
63 int processing_template_parmlist;
64 static int template_header_count;
66 static GTY(()) tree saved_trees;
67 static VEC(int,heap) *inline_parm_levels;
69 static GTY(()) struct tinst_level *current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 typedef struct GTY(()) spec_entry
90 static GTY ((param_is (spec_entry)))
91 htab_t decl_specializations;
93 static GTY ((param_is (spec_entry)))
94 htab_t type_specializations;
96 /* Contains canonical template parameter types. The vector is indexed by
97 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
98 TREE_LIST, whose TREE_VALUEs contain the canonical template
99 parameters of various types and levels. */
100 static GTY(()) VEC(tree,gc) *canonical_template_parms;
102 #define UNIFY_ALLOW_NONE 0
103 #define UNIFY_ALLOW_MORE_CV_QUAL 1
104 #define UNIFY_ALLOW_LESS_CV_QUAL 2
105 #define UNIFY_ALLOW_DERIVED 4
106 #define UNIFY_ALLOW_INTEGER 8
107 #define UNIFY_ALLOW_OUTER_LEVEL 16
108 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
109 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
111 static void push_access_scope (tree);
112 static void pop_access_scope (tree);
113 static bool resolve_overloaded_unification (tree, tree, tree, tree,
114 unification_kind_t, int);
115 static int try_one_overload (tree, tree, tree, tree, tree,
116 unification_kind_t, int, bool);
117 static int unify (tree, tree, tree, tree, int);
118 static void add_pending_template (tree);
119 static tree reopen_tinst_level (struct tinst_level *);
120 static tree tsubst_initializer_list (tree, tree);
121 static tree get_class_bindings (tree, tree, tree);
122 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
124 static void tsubst_enum (tree, tree, tree);
125 static tree add_to_template_args (tree, tree);
126 static tree add_outermost_template_args (tree, tree);
127 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
128 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
130 static int type_unification_real (tree, tree, tree, const tree *,
131 unsigned int, int, unification_kind_t, int);
132 static void note_template_header (int);
133 static tree convert_nontype_argument_function (tree, tree);
134 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
135 static tree convert_template_argument (tree, tree, tree,
136 tsubst_flags_t, int, tree);
137 static int for_each_template_parm (tree, tree_fn_t, void*,
138 struct pointer_set_t*, bool);
139 static tree expand_template_argument_pack (tree);
140 static tree build_template_parm_index (int, int, int, int, tree, tree);
141 static bool inline_needs_template_parms (tree);
142 static void push_inline_template_parms_recursive (tree, int);
143 static tree retrieve_local_specialization (tree);
144 static void register_local_specialization (tree, tree);
145 static hashval_t hash_specialization (const void *p);
146 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
147 static int mark_template_parm (tree, void *);
148 static int template_parm_this_level_p (tree, void *);
149 static tree tsubst_friend_function (tree, tree);
150 static tree tsubst_friend_class (tree, tree);
151 static int can_complete_type_without_circularity (tree);
152 static tree get_bindings (tree, tree, tree, bool);
153 static int template_decl_level (tree);
154 static int check_cv_quals_for_unify (int, tree, tree);
155 static void template_parm_level_and_index (tree, int*, int*);
156 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
157 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
158 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
159 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
160 static void regenerate_decl_from_template (tree, tree);
161 static tree most_specialized_class (tree, tree, tsubst_flags_t);
162 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
163 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
165 static bool check_specialization_scope (void);
166 static tree process_partial_specialization (tree);
167 static void set_current_access_from_decl (tree);
168 static tree get_template_base (tree, tree, tree, tree);
169 static tree try_class_unification (tree, tree, tree, tree);
170 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
172 static bool template_template_parm_bindings_ok_p (tree, tree);
173 static int template_args_equal (tree, tree);
174 static void tsubst_default_arguments (tree);
175 static tree for_each_template_parm_r (tree *, int *, void *);
176 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
177 static void copy_default_args_to_explicit_spec (tree);
178 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
179 static int eq_local_specializations (const void *, const void *);
180 static bool dependent_template_arg_p (tree);
181 static bool any_template_arguments_need_structural_equality_p (tree);
182 static bool dependent_type_p_r (tree);
183 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
184 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
185 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
186 static tree tsubst_decl (tree, tree, tsubst_flags_t);
187 static void perform_typedefs_access_check (tree tmpl, tree targs);
188 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
190 static tree listify (tree);
191 static tree listify_autos (tree, tree);
192 static tree template_parm_to_arg (tree t);
193 static tree current_template_args (void);
194 static tree fixup_template_type_parm_type (tree, int);
195 static tree fixup_template_parm_index (tree, tree, int);
196 static void fixup_template_parms (void);
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_CHAIN (arg))
1520 val = iterative_hash_template_arg (OVL_FUNCTION (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))
1536 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1537 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1540 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1543 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1544 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1546 case TEMPLATE_PARM_INDEX:
1547 val = iterative_hash_template_arg
1548 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1549 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1550 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1553 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1554 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1555 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1558 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1560 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1564 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1565 code = TREE_CODE (TREE_OPERAND (arg, 1));
1566 val = iterative_hash_object (code, val);
1567 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1570 /* layout_type sets structural equality for arrays of
1571 incomplete type, so we can't rely on the canonical type
1573 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1574 return iterative_hash_template_arg (TYPE_DOMAIN (arg), val);
1577 /* A lambda can't appear in a template arg, but don't crash on
1579 gcc_assert (seen_error ());
1583 case STATIC_CAST_EXPR:
1584 case REINTERPRET_CAST_EXPR:
1585 case CONST_CAST_EXPR:
1586 case DYNAMIC_CAST_EXPR:
1588 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1589 /* Now hash operands as usual. */
1599 if (TYPE_CANONICAL (arg))
1600 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1602 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1603 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1604 /* Otherwise just compare the types during lookup. */
1607 case tcc_declaration:
1609 return iterative_hash_expr (arg, val);
1612 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1614 unsigned n = TREE_OPERAND_LENGTH (arg);
1615 for (i = 0; i < n; ++i)
1616 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1624 /* Unregister the specialization SPEC as a specialization of TMPL.
1625 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1626 if the SPEC was listed as a specialization of TMPL.
1628 Note that SPEC has been ggc_freed, so we can't look inside it. */
1631 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1636 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1637 elt.args = TI_ARGS (tinfo);
1638 elt.spec = NULL_TREE;
1640 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1643 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1644 gcc_assert (new_spec != NULL_TREE);
1645 (*slot)->spec = new_spec;
1652 /* Compare an entry in the local specializations hash table P1 (which
1653 is really a pointer to a TREE_LIST) with P2 (which is really a
1657 eq_local_specializations (const void *p1, const void *p2)
1659 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1662 /* Hash P1, an entry in the local specializations table. */
1665 hash_local_specialization (const void* p1)
1667 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1670 /* Like register_specialization, but for local declarations. We are
1671 registering SPEC, an instantiation of TMPL. */
1674 register_local_specialization (tree spec, tree tmpl)
1678 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1679 htab_hash_pointer (tmpl), INSERT);
1680 *slot = build_tree_list (spec, tmpl);
1683 /* TYPE is a class type. Returns true if TYPE is an explicitly
1684 specialized class. */
1687 explicit_class_specialization_p (tree type)
1689 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1691 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1694 /* Print the list of functions at FNS, going through all the overloads
1695 for each element of the list. Alternatively, FNS can not be a
1696 TREE_LIST, in which case it will be printed together with all the
1699 MORE and *STR should respectively be FALSE and NULL when the function
1700 is called from the outside. They are used internally on recursive
1701 calls. print_candidates manages the two parameters and leaves NULL
1702 in *STR when it ends. */
1705 print_candidates_1 (tree fns, bool more, const char **str)
1708 char *spaces = NULL;
1710 for (fn = fns; fn; fn = OVL_NEXT (fn))
1711 if (TREE_CODE (fn) == TREE_LIST)
1713 gcc_assert (!OVL_NEXT (fn) && !is_overloaded_fn (fn));
1714 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1715 print_candidates_1 (TREE_VALUE (fn2),
1716 TREE_CHAIN (fn2) || more, str);
1722 /* Pick the prefix string. */
1723 if (!more && !OVL_NEXT (fns))
1725 error ("candidate is: %+#D", OVL_CURRENT (fn));
1729 *str = _("candidates are:");
1730 spaces = get_spaces (*str);
1732 error ("%s %+#D", *str, OVL_CURRENT (fn));
1733 *str = spaces ? spaces : *str;
1743 /* Print the list of candidate FNS in an error message. */
1746 print_candidates (tree fns)
1748 const char *str = NULL;
1749 print_candidates_1 (fns, false, &str);
1750 gcc_assert (str == NULL);
1753 /* Returns the template (one of the functions given by TEMPLATE_ID)
1754 which can be specialized to match the indicated DECL with the
1755 explicit template args given in TEMPLATE_ID. The DECL may be
1756 NULL_TREE if none is available. In that case, the functions in
1757 TEMPLATE_ID are non-members.
1759 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1760 specialization of a member template.
1762 The TEMPLATE_COUNT is the number of references to qualifying
1763 template classes that appeared in the name of the function. See
1764 check_explicit_specialization for a more accurate description.
1766 TSK indicates what kind of template declaration (if any) is being
1767 declared. TSK_TEMPLATE indicates that the declaration given by
1768 DECL, though a FUNCTION_DECL, has template parameters, and is
1769 therefore a template function.
1771 The template args (those explicitly specified and those deduced)
1772 are output in a newly created vector *TARGS_OUT.
1774 If it is impossible to determine the result, an error message is
1775 issued. The error_mark_node is returned to indicate failure. */
1778 determine_specialization (tree template_id,
1781 int need_member_template,
1787 tree explicit_targs;
1788 tree candidates = NULL_TREE;
1789 /* A TREE_LIST of templates of which DECL may be a specialization.
1790 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1791 corresponding TREE_PURPOSE is the set of template arguments that,
1792 when used to instantiate the template, would produce a function
1793 with the signature of DECL. */
1794 tree templates = NULL_TREE;
1796 struct cp_binding_level *b;
1798 *targs_out = NULL_TREE;
1800 if (template_id == error_mark_node || decl == error_mark_node)
1801 return error_mark_node;
1803 fns = TREE_OPERAND (template_id, 0);
1804 explicit_targs = TREE_OPERAND (template_id, 1);
1806 if (fns == error_mark_node)
1807 return error_mark_node;
1809 /* Check for baselinks. */
1810 if (BASELINK_P (fns))
1811 fns = BASELINK_FUNCTIONS (fns);
1813 if (!is_overloaded_fn (fns))
1815 error ("%qD is not a function template", fns);
1816 return error_mark_node;
1819 /* Count the number of template headers specified for this
1822 for (b = current_binding_level;
1823 b->kind == sk_template_parms;
1827 for (; fns; fns = OVL_NEXT (fns))
1829 tree fn = OVL_CURRENT (fns);
1831 if (TREE_CODE (fn) == TEMPLATE_DECL)
1833 tree decl_arg_types;
1836 /* In case of explicit specialization, we need to check if
1837 the number of template headers appearing in the specialization
1838 is correct. This is usually done in check_explicit_specialization,
1839 but the check done there cannot be exhaustive when specializing
1840 member functions. Consider the following code:
1842 template <> void A<int>::f(int);
1843 template <> template <> void A<int>::f(int);
1845 Assuming that A<int> is not itself an explicit specialization
1846 already, the first line specializes "f" which is a non-template
1847 member function, whilst the second line specializes "f" which
1848 is a template member function. So both lines are syntactically
1849 correct, and check_explicit_specialization does not reject
1852 Here, we can do better, as we are matching the specialization
1853 against the declarations. We count the number of template
1854 headers, and we check if they match TEMPLATE_COUNT + 1
1855 (TEMPLATE_COUNT is the number of qualifying template classes,
1856 plus there must be another header for the member template
1859 Notice that if header_count is zero, this is not a
1860 specialization but rather a template instantiation, so there
1861 is no check we can perform here. */
1862 if (header_count && header_count != template_count + 1)
1865 /* Check that the number of template arguments at the
1866 innermost level for DECL is the same as for FN. */
1867 if (current_binding_level->kind == sk_template_parms
1868 && !current_binding_level->explicit_spec_p
1869 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1870 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1871 (current_template_parms))))
1874 /* DECL might be a specialization of FN. */
1875 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1876 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1878 /* For a non-static member function, we need to make sure
1879 that the const qualification is the same. Since
1880 get_bindings does not try to merge the "this" parameter,
1881 we must do the comparison explicitly. */
1882 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1883 && !same_type_p (TREE_VALUE (fn_arg_types),
1884 TREE_VALUE (decl_arg_types)))
1887 /* Skip the "this" parameter and, for constructors of
1888 classes with virtual bases, the VTT parameter. A
1889 full specialization of a constructor will have a VTT
1890 parameter, but a template never will. */
1892 = skip_artificial_parms_for (decl, decl_arg_types);
1894 = skip_artificial_parms_for (fn, fn_arg_types);
1896 /* Check that the number of function parameters matches.
1898 template <class T> void f(int i = 0);
1899 template <> void f<int>();
1900 The specialization f<int> is invalid but is not caught
1901 by get_bindings below. */
1902 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1905 /* Function templates cannot be specializations; there are
1906 no partial specializations of functions. Therefore, if
1907 the type of DECL does not match FN, there is no
1909 if (tsk == tsk_template)
1911 if (compparms (fn_arg_types, decl_arg_types))
1912 candidates = tree_cons (NULL_TREE, fn, candidates);
1916 /* See whether this function might be a specialization of this
1918 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1921 /* We cannot deduce template arguments that when used to
1922 specialize TMPL will produce DECL. */
1925 /* Save this template, and the arguments deduced. */
1926 templates = tree_cons (targs, fn, templates);
1928 else if (need_member_template)
1929 /* FN is an ordinary member function, and we need a
1930 specialization of a member template. */
1932 else if (TREE_CODE (fn) != FUNCTION_DECL)
1933 /* We can get IDENTIFIER_NODEs here in certain erroneous
1936 else if (!DECL_FUNCTION_MEMBER_P (fn))
1937 /* This is just an ordinary non-member function. Nothing can
1938 be a specialization of that. */
1940 else if (DECL_ARTIFICIAL (fn))
1941 /* Cannot specialize functions that are created implicitly. */
1945 tree decl_arg_types;
1947 /* This is an ordinary member function. However, since
1948 we're here, we can assume it's enclosing class is a
1949 template class. For example,
1951 template <typename T> struct S { void f(); };
1952 template <> void S<int>::f() {}
1954 Here, S<int>::f is a non-template, but S<int> is a
1955 template class. If FN has the same type as DECL, we
1956 might be in business. */
1958 if (!DECL_TEMPLATE_INFO (fn))
1959 /* Its enclosing class is an explicit specialization
1960 of a template class. This is not a candidate. */
1963 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1964 TREE_TYPE (TREE_TYPE (fn))))
1965 /* The return types differ. */
1968 /* Adjust the type of DECL in case FN is a static member. */
1969 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1970 if (DECL_STATIC_FUNCTION_P (fn)
1971 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1972 decl_arg_types = TREE_CHAIN (decl_arg_types);
1974 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1977 candidates = tree_cons (NULL_TREE, fn, candidates);
1981 if (templates && TREE_CHAIN (templates))
1987 It is possible for a specialization with a given function
1988 signature to be instantiated from more than one function
1989 template. In such cases, explicit specification of the
1990 template arguments must be used to uniquely identify the
1991 function template specialization being specialized.
1993 Note that here, there's no suggestion that we're supposed to
1994 determine which of the candidate templates is most
1995 specialized. However, we, also have:
1999 Partial ordering of overloaded function template
2000 declarations is used in the following contexts to select
2001 the function template to which a function template
2002 specialization refers:
2004 -- when an explicit specialization refers to a function
2007 So, we do use the partial ordering rules, at least for now.
2008 This extension can only serve to make invalid programs valid,
2009 so it's safe. And, there is strong anecdotal evidence that
2010 the committee intended the partial ordering rules to apply;
2011 the EDG front end has that behavior, and John Spicer claims
2012 that the committee simply forgot to delete the wording in
2013 [temp.expl.spec]. */
2014 tree tmpl = most_specialized_instantiation (templates);
2015 if (tmpl != error_mark_node)
2018 TREE_CHAIN (templates) = NULL_TREE;
2022 if (templates == NULL_TREE && candidates == NULL_TREE)
2024 error ("template-id %qD for %q+D does not match any template "
2025 "declaration", template_id, decl);
2026 if (header_count && header_count != template_count + 1)
2027 inform (input_location, "saw %d %<template<>%>, need %d for "
2028 "specializing a member function template",
2029 header_count, template_count + 1);
2030 return error_mark_node;
2032 else if ((templates && TREE_CHAIN (templates))
2033 || (candidates && TREE_CHAIN (candidates))
2034 || (templates && candidates))
2036 error ("ambiguous template specialization %qD for %q+D",
2038 candidates = chainon (candidates, templates);
2039 print_candidates (candidates);
2040 return error_mark_node;
2043 /* We have one, and exactly one, match. */
2046 tree fn = TREE_VALUE (candidates);
2047 *targs_out = copy_node (DECL_TI_ARGS (fn));
2048 /* DECL is a re-declaration or partial instantiation of a template
2050 if (TREE_CODE (fn) == TEMPLATE_DECL)
2052 /* It was a specialization of an ordinary member function in a
2054 return DECL_TI_TEMPLATE (fn);
2057 /* It was a specialization of a template. */
2058 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2059 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2061 *targs_out = copy_node (targs);
2062 SET_TMPL_ARGS_LEVEL (*targs_out,
2063 TMPL_ARGS_DEPTH (*targs_out),
2064 TREE_PURPOSE (templates));
2067 *targs_out = TREE_PURPOSE (templates);
2068 return TREE_VALUE (templates);
2071 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2072 but with the default argument values filled in from those in the
2076 copy_default_args_to_explicit_spec_1 (tree spec_types,
2079 tree new_spec_types;
2084 if (spec_types == void_list_node)
2085 return void_list_node;
2087 /* Substitute into the rest of the list. */
2089 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2090 TREE_CHAIN (tmpl_types));
2092 /* Add the default argument for this parameter. */
2093 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2094 TREE_VALUE (spec_types),
2098 /* DECL is an explicit specialization. Replicate default arguments
2099 from the template it specializes. (That way, code like:
2101 template <class T> void f(T = 3);
2102 template <> void f(double);
2105 works, as required.) An alternative approach would be to look up
2106 the correct default arguments at the call-site, but this approach
2107 is consistent with how implicit instantiations are handled. */
2110 copy_default_args_to_explicit_spec (tree decl)
2115 tree new_spec_types;
2119 tree object_type = NULL_TREE;
2120 tree in_charge = NULL_TREE;
2121 tree vtt = NULL_TREE;
2123 /* See if there's anything we need to do. */
2124 tmpl = DECL_TI_TEMPLATE (decl);
2125 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2126 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2127 if (TREE_PURPOSE (t))
2132 old_type = TREE_TYPE (decl);
2133 spec_types = TYPE_ARG_TYPES (old_type);
2135 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2137 /* Remove the this pointer, but remember the object's type for
2139 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2140 spec_types = TREE_CHAIN (spec_types);
2141 tmpl_types = TREE_CHAIN (tmpl_types);
2143 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2145 /* DECL may contain more parameters than TMPL due to the extra
2146 in-charge parameter in constructors and destructors. */
2147 in_charge = spec_types;
2148 spec_types = TREE_CHAIN (spec_types);
2150 if (DECL_HAS_VTT_PARM_P (decl))
2153 spec_types = TREE_CHAIN (spec_types);
2157 /* Compute the merged default arguments. */
2159 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2161 /* Compute the new FUNCTION_TYPE. */
2165 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2170 /* Put the in-charge parameter back. */
2171 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2172 TREE_VALUE (in_charge),
2175 new_type = build_method_type_directly (object_type,
2176 TREE_TYPE (old_type),
2180 new_type = build_function_type (TREE_TYPE (old_type),
2182 new_type = cp_build_type_attribute_variant (new_type,
2183 TYPE_ATTRIBUTES (old_type));
2184 new_type = build_exception_variant (new_type,
2185 TYPE_RAISES_EXCEPTIONS (old_type));
2186 TREE_TYPE (decl) = new_type;
2189 /* Check to see if the function just declared, as indicated in
2190 DECLARATOR, and in DECL, is a specialization of a function
2191 template. We may also discover that the declaration is an explicit
2192 instantiation at this point.
2194 Returns DECL, or an equivalent declaration that should be used
2195 instead if all goes well. Issues an error message if something is
2196 amiss. Returns error_mark_node if the error is not easily
2199 FLAGS is a bitmask consisting of the following flags:
2201 2: The function has a definition.
2202 4: The function is a friend.
2204 The TEMPLATE_COUNT is the number of references to qualifying
2205 template classes that appeared in the name of the function. For
2208 template <class T> struct S { void f(); };
2211 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2212 classes are not counted in the TEMPLATE_COUNT, so that in
2214 template <class T> struct S {};
2215 template <> struct S<int> { void f(); }
2216 template <> void S<int>::f();
2218 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2219 invalid; there should be no template <>.)
2221 If the function is a specialization, it is marked as such via
2222 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2223 is set up correctly, and it is added to the list of specializations
2224 for that template. */
2227 check_explicit_specialization (tree declarator,
2232 int have_def = flags & 2;
2233 int is_friend = flags & 4;
2234 int specialization = 0;
2235 int explicit_instantiation = 0;
2236 int member_specialization = 0;
2237 tree ctype = DECL_CLASS_CONTEXT (decl);
2238 tree dname = DECL_NAME (decl);
2243 if (!processing_specialization)
2246 tsk = tsk_excessive_parms;
2249 tsk = current_tmpl_spec_kind (template_count);
2254 if (processing_specialization)
2257 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2259 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2262 /* This could be something like:
2264 template <class T> void f(T);
2265 class S { friend void f<>(int); } */
2269 /* This case handles bogus declarations like template <>
2270 template <class T> void f<int>(); */
2272 error ("template-id %qD in declaration of primary template",
2279 case tsk_invalid_member_spec:
2280 /* The error has already been reported in
2281 check_specialization_scope. */
2282 return error_mark_node;
2284 case tsk_invalid_expl_inst:
2285 error ("template parameter list used in explicit instantiation");
2291 error ("definition provided for explicit instantiation");
2293 explicit_instantiation = 1;
2296 case tsk_excessive_parms:
2297 case tsk_insufficient_parms:
2298 if (tsk == tsk_excessive_parms)
2299 error ("too many template parameter lists in declaration of %qD",
2301 else if (template_header_count)
2302 error("too few template parameter lists in declaration of %qD", decl);
2304 error("explicit specialization of %qD must be introduced by "
2305 "%<template <>%>", decl);
2309 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2311 member_specialization = 1;
2317 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2319 /* This case handles bogus declarations like template <>
2320 template <class T> void f<int>(); */
2322 if (uses_template_parms (declarator))
2323 error ("function template partial specialization %qD "
2324 "is not allowed", declarator);
2326 error ("template-id %qD in declaration of primary template",
2331 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2332 /* This is a specialization of a member template, without
2333 specialization the containing class. Something like:
2335 template <class T> struct S {
2336 template <class U> void f (U);
2338 template <> template <class U> void S<int>::f(U) {}
2340 That's a specialization -- but of the entire template. */
2348 if (specialization || member_specialization)
2350 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2351 for (; t; t = TREE_CHAIN (t))
2352 if (TREE_PURPOSE (t))
2354 permerror (input_location,
2355 "default argument specified in explicit specialization");
2360 if (specialization || member_specialization || explicit_instantiation)
2362 tree tmpl = NULL_TREE;
2363 tree targs = NULL_TREE;
2365 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2366 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2370 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2375 /* If there is no class context, the explicit instantiation
2376 must be at namespace scope. */
2377 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2379 /* Find the namespace binding, using the declaration
2381 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2383 if (fns == error_mark_node || !is_overloaded_fn (fns))
2385 error ("%qD is not a template function", dname);
2386 fns = error_mark_node;
2390 tree fn = OVL_CURRENT (fns);
2391 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2392 CP_DECL_CONTEXT (fn)))
2393 error ("%qD is not declared in %qD",
2394 decl, current_namespace);
2398 declarator = lookup_template_function (fns, NULL_TREE);
2401 if (declarator == error_mark_node)
2402 return error_mark_node;
2404 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2406 if (!explicit_instantiation)
2407 /* A specialization in class scope. This is invalid,
2408 but the error will already have been flagged by
2409 check_specialization_scope. */
2410 return error_mark_node;
2413 /* It's not valid to write an explicit instantiation in
2416 class C { template void f(); }
2418 This case is caught by the parser. However, on
2421 template class C { void f(); };
2423 (which is invalid) we can get here. The error will be
2430 else if (ctype != NULL_TREE
2431 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2434 /* Find the list of functions in ctype that have the same
2435 name as the declared function. */
2436 tree name = TREE_OPERAND (declarator, 0);
2437 tree fns = NULL_TREE;
2440 if (constructor_name_p (name, ctype))
2442 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2444 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2445 : !CLASSTYPE_DESTRUCTORS (ctype))
2447 /* From [temp.expl.spec]:
2449 If such an explicit specialization for the member
2450 of a class template names an implicitly-declared
2451 special member function (clause _special_), the
2452 program is ill-formed.
2454 Similar language is found in [temp.explicit]. */
2455 error ("specialization of implicitly-declared special member function");
2456 return error_mark_node;
2459 name = is_constructor ? ctor_identifier : dtor_identifier;
2462 if (!DECL_CONV_FN_P (decl))
2464 idx = lookup_fnfields_1 (ctype, name);
2466 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2470 VEC(tree,gc) *methods;
2473 /* For a type-conversion operator, we cannot do a
2474 name-based lookup. We might be looking for `operator
2475 int' which will be a specialization of `operator T'.
2476 So, we find *all* the conversion operators, and then
2477 select from them. */
2480 methods = CLASSTYPE_METHOD_VEC (ctype);
2482 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2483 VEC_iterate (tree, methods, idx, ovl);
2486 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2487 /* There are no more conversion functions. */
2490 /* Glue all these conversion functions together
2491 with those we already have. */
2492 for (; ovl; ovl = OVL_NEXT (ovl))
2493 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2497 if (fns == NULL_TREE)
2499 error ("no member function %qD declared in %qT", name, ctype);
2500 return error_mark_node;
2503 TREE_OPERAND (declarator, 0) = fns;
2506 /* Figure out what exactly is being specialized at this point.
2507 Note that for an explicit instantiation, even one for a
2508 member function, we cannot tell apriori whether the
2509 instantiation is for a member template, or just a member
2510 function of a template class. Even if a member template is
2511 being instantiated, the member template arguments may be
2512 elided if they can be deduced from the rest of the
2514 tmpl = determine_specialization (declarator, decl,
2516 member_specialization,
2520 if (!tmpl || tmpl == error_mark_node)
2521 /* We couldn't figure out what this declaration was
2523 return error_mark_node;
2526 tree gen_tmpl = most_general_template (tmpl);
2528 if (explicit_instantiation)
2530 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2531 is done by do_decl_instantiation later. */
2533 int arg_depth = TMPL_ARGS_DEPTH (targs);
2534 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2536 if (arg_depth > parm_depth)
2538 /* If TMPL is not the most general template (for
2539 example, if TMPL is a friend template that is
2540 injected into namespace scope), then there will
2541 be too many levels of TARGS. Remove some of them
2546 new_targs = make_tree_vec (parm_depth);
2547 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2548 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2549 = TREE_VEC_ELT (targs, i);
2553 return instantiate_template (tmpl, targs, tf_error);
2556 /* If we thought that the DECL was a member function, but it
2557 turns out to be specializing a static member function,
2558 make DECL a static member function as well. */
2559 if (DECL_STATIC_FUNCTION_P (tmpl)
2560 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2561 revert_static_member_fn (decl);
2563 /* If this is a specialization of a member template of a
2564 template class, we want to return the TEMPLATE_DECL, not
2565 the specialization of it. */
2566 if (tsk == tsk_template)
2568 tree result = DECL_TEMPLATE_RESULT (tmpl);
2569 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2570 DECL_INITIAL (result) = NULL_TREE;
2574 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2575 DECL_SOURCE_LOCATION (result)
2576 = DECL_SOURCE_LOCATION (decl);
2577 /* We want to use the argument list specified in the
2578 definition, not in the original declaration. */
2579 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2580 for (parm = DECL_ARGUMENTS (result); parm;
2581 parm = DECL_CHAIN (parm))
2582 DECL_CONTEXT (parm) = result;
2584 return register_specialization (tmpl, gen_tmpl, targs,
2588 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2589 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2591 /* Inherit default function arguments from the template
2592 DECL is specializing. */
2593 copy_default_args_to_explicit_spec (decl);
2595 /* This specialization has the same protection as the
2596 template it specializes. */
2597 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2598 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2600 /* 7.1.1-1 [dcl.stc]
2602 A storage-class-specifier shall not be specified in an
2603 explicit specialization...
2605 The parser rejects these, so unless action is taken here,
2606 explicit function specializations will always appear with
2609 The action recommended by the C++ CWG in response to C++
2610 defect report 605 is to make the storage class and linkage
2611 of the explicit specialization match the templated function:
2613 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2615 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2617 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2618 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2620 /* This specialization has the same linkage and visibility as
2621 the function template it specializes. */
2622 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2623 if (! TREE_PUBLIC (decl))
2625 DECL_INTERFACE_KNOWN (decl) = 1;
2626 DECL_NOT_REALLY_EXTERN (decl) = 1;
2628 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2629 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2631 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2632 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2636 /* If DECL is a friend declaration, declared using an
2637 unqualified name, the namespace associated with DECL may
2638 have been set incorrectly. For example, in:
2640 template <typename T> void f(T);
2642 struct S { friend void f<int>(int); }
2645 we will have set the DECL_CONTEXT for the friend
2646 declaration to N, rather than to the global namespace. */
2647 if (DECL_NAMESPACE_SCOPE_P (decl))
2648 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2650 if (is_friend && !have_def)
2651 /* This is not really a declaration of a specialization.
2652 It's just the name of an instantiation. But, it's not
2653 a request for an instantiation, either. */
2654 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2655 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2656 /* This is indeed a specialization. In case of constructors
2657 and destructors, we need in-charge and not-in-charge
2658 versions in V3 ABI. */
2659 clone_function_decl (decl, /*update_method_vec_p=*/0);
2661 /* Register this specialization so that we can find it
2663 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2670 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2671 parameters. These are represented in the same format used for
2672 DECL_TEMPLATE_PARMS. */
2675 comp_template_parms (const_tree parms1, const_tree parms2)
2680 if (parms1 == parms2)
2683 for (p1 = parms1, p2 = parms2;
2684 p1 != NULL_TREE && p2 != NULL_TREE;
2685 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2687 tree t1 = TREE_VALUE (p1);
2688 tree t2 = TREE_VALUE (p2);
2691 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2692 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2694 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2697 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2699 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2700 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2702 /* If either of the template parameters are invalid, assume
2703 they match for the sake of error recovery. */
2704 if (parm1 == error_mark_node || parm2 == error_mark_node)
2707 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2710 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2711 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2712 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2714 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2719 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2720 /* One set of parameters has more parameters lists than the
2727 /* Determine whether PARM is a parameter pack. */
2730 template_parameter_pack_p (const_tree parm)
2732 /* Determine if we have a non-type template parameter pack. */
2733 if (TREE_CODE (parm) == PARM_DECL)
2734 return (DECL_TEMPLATE_PARM_P (parm)
2735 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2737 /* If this is a list of template parameters, we could get a
2738 TYPE_DECL or a TEMPLATE_DECL. */
2739 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2740 parm = TREE_TYPE (parm);
2742 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2743 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2744 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2747 /* Determine if T is a function parameter pack. */
2750 function_parameter_pack_p (const_tree t)
2752 if (t && TREE_CODE (t) == PARM_DECL)
2753 return FUNCTION_PARAMETER_PACK_P (t);
2757 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2758 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2761 get_function_template_decl (const_tree primary_func_tmpl_inst)
2763 if (! primary_func_tmpl_inst
2764 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2765 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2768 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2771 /* Return true iff the function parameter PARAM_DECL was expanded
2772 from the function parameter pack PACK. */
2775 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2777 if (DECL_ARTIFICIAL (param_decl)
2778 || !function_parameter_pack_p (pack))
2781 /* The parameter pack and its pack arguments have the same
2783 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2786 /* Determine whether ARGS describes a variadic template args list,
2787 i.e., one that is terminated by a template argument pack. */
2790 template_args_variadic_p (tree args)
2795 if (args == NULL_TREE)
2798 args = INNERMOST_TEMPLATE_ARGS (args);
2799 nargs = TREE_VEC_LENGTH (args);
2804 last_parm = TREE_VEC_ELT (args, nargs - 1);
2806 return ARGUMENT_PACK_P (last_parm);
2809 /* Generate a new name for the parameter pack name NAME (an
2810 IDENTIFIER_NODE) that incorporates its */
2813 make_ith_pack_parameter_name (tree name, int i)
2815 /* Munge the name to include the parameter index. */
2816 #define NUMBUF_LEN 128
2817 char numbuf[NUMBUF_LEN];
2821 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2822 newname_len = IDENTIFIER_LENGTH (name)
2823 + strlen (numbuf) + 2;
2824 newname = (char*)alloca (newname_len);
2825 snprintf (newname, newname_len,
2826 "%s#%i", IDENTIFIER_POINTER (name), i);
2827 return get_identifier (newname);
2830 /* Return true if T is a primary function
2831 or class template instantiation. */
2834 primary_template_instantiation_p (const_tree t)
2839 if (TREE_CODE (t) == FUNCTION_DECL)
2840 return DECL_LANG_SPECIFIC (t)
2841 && DECL_TEMPLATE_INSTANTIATION (t)
2842 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2843 else if (CLASS_TYPE_P (t))
2844 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2845 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2849 /* Return true if PARM is a template template parameter. */
2852 template_template_parameter_p (const_tree parm)
2854 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2857 /* Return the template parameters of T if T is a
2858 primary template instantiation, NULL otherwise. */
2861 get_primary_template_innermost_parameters (const_tree t)
2863 tree parms = NULL, template_info = NULL;
2865 if ((template_info = get_template_info (t))
2866 && primary_template_instantiation_p (t))
2867 parms = INNERMOST_TEMPLATE_PARMS
2868 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2873 /* Return the template parameters of the LEVELth level from the full list
2874 of template parameters PARMS. */
2877 get_template_parms_at_level (tree parms, int level)
2881 || TREE_CODE (parms) != TREE_LIST
2882 || level > TMPL_PARMS_DEPTH (parms))
2885 for (p = parms; p; p = TREE_CHAIN (p))
2886 if (TMPL_PARMS_DEPTH (p) == level)
2892 /* Returns the template arguments of T if T is a template instantiation,
2896 get_template_innermost_arguments (const_tree t)
2898 tree args = NULL, template_info = NULL;
2900 if ((template_info = get_template_info (t))
2901 && TI_ARGS (template_info))
2902 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2907 /* Return the argument pack elements of T if T is a template argument pack,
2911 get_template_argument_pack_elems (const_tree t)
2913 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2914 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2917 return ARGUMENT_PACK_ARGS (t);
2920 /* Structure used to track the progress of find_parameter_packs_r. */
2921 struct find_parameter_pack_data
2923 /* TREE_LIST that will contain all of the parameter packs found by
2925 tree* parameter_packs;
2927 /* Set of AST nodes that have been visited by the traversal. */
2928 struct pointer_set_t *visited;
2931 /* Identifies all of the argument packs that occur in a template
2932 argument and appends them to the TREE_LIST inside DATA, which is a
2933 find_parameter_pack_data structure. This is a subroutine of
2934 make_pack_expansion and uses_parameter_packs. */
2936 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2939 struct find_parameter_pack_data* ppd =
2940 (struct find_parameter_pack_data*)data;
2941 bool parameter_pack_p = false;
2943 /* Identify whether this is a parameter pack or not. */
2944 switch (TREE_CODE (t))
2946 case TEMPLATE_PARM_INDEX:
2947 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2948 parameter_pack_p = true;
2951 case TEMPLATE_TYPE_PARM:
2952 case TEMPLATE_TEMPLATE_PARM:
2953 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2954 parameter_pack_p = true;
2958 if (FUNCTION_PARAMETER_PACK_P (t))
2960 /* We don't want to walk into the type of a PARM_DECL,
2961 because we don't want to see the type parameter pack. */
2963 parameter_pack_p = true;
2968 /* Not a parameter pack. */
2972 if (parameter_pack_p)
2974 /* Add this parameter pack to the list. */
2975 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2979 cp_walk_tree (&TYPE_CONTEXT (t),
2980 &find_parameter_packs_r, ppd, ppd->visited);
2982 /* This switch statement will return immediately if we don't find a
2984 switch (TREE_CODE (t))
2986 case TEMPLATE_PARM_INDEX:
2989 case BOUND_TEMPLATE_TEMPLATE_PARM:
2990 /* Check the template itself. */
2991 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2992 &find_parameter_packs_r, ppd, ppd->visited);
2993 /* Check the template arguments. */
2994 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2999 case TEMPLATE_TYPE_PARM:
3000 case TEMPLATE_TEMPLATE_PARM:
3007 if (TYPE_PTRMEMFUNC_P (t))
3013 if (TYPE_TEMPLATE_INFO (t))
3014 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3015 &find_parameter_packs_r, ppd, ppd->visited);
3021 cp_walk_tree (&TREE_TYPE (t),
3022 &find_parameter_packs_r, ppd, ppd->visited);
3026 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3031 case TYPE_PACK_EXPANSION:
3032 case EXPR_PACK_EXPANSION:
3037 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3042 case IDENTIFIER_NODE:
3043 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3055 /* Determines if the expression or type T uses any parameter packs. */
3057 uses_parameter_packs (tree t)
3059 tree parameter_packs = NULL_TREE;
3060 struct find_parameter_pack_data ppd;
3061 ppd.parameter_packs = ¶meter_packs;
3062 ppd.visited = pointer_set_create ();
3063 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3064 pointer_set_destroy (ppd.visited);
3065 return parameter_packs != NULL_TREE;
3068 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3069 representation a base-class initializer into a parameter pack
3070 expansion. If all goes well, the resulting node will be an
3071 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3074 make_pack_expansion (tree arg)
3077 tree parameter_packs = NULL_TREE;
3078 bool for_types = false;
3079 struct find_parameter_pack_data ppd;
3081 if (!arg || arg == error_mark_node)
3084 if (TREE_CODE (arg) == TREE_LIST)
3086 /* The only time we will see a TREE_LIST here is for a base
3087 class initializer. In this case, the TREE_PURPOSE will be a
3088 _TYPE node (representing the base class expansion we're
3089 initializing) and the TREE_VALUE will be a TREE_LIST
3090 containing the initialization arguments.
3092 The resulting expansion looks somewhat different from most
3093 expansions. Rather than returning just one _EXPANSION, we
3094 return a TREE_LIST whose TREE_PURPOSE is a
3095 TYPE_PACK_EXPANSION containing the bases that will be
3096 initialized. The TREE_VALUE will be identical to the
3097 original TREE_VALUE, which is a list of arguments that will
3098 be passed to each base. We do not introduce any new pack
3099 expansion nodes into the TREE_VALUE (although it is possible
3100 that some already exist), because the TREE_PURPOSE and
3101 TREE_VALUE all need to be expanded together with the same
3102 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3103 resulting TREE_PURPOSE will mention the parameter packs in
3104 both the bases and the arguments to the bases. */
3107 tree parameter_packs = NULL_TREE;
3109 /* Determine which parameter packs will be used by the base
3111 ppd.visited = pointer_set_create ();
3112 ppd.parameter_packs = ¶meter_packs;
3113 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3116 if (parameter_packs == NULL_TREE)
3118 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3119 pointer_set_destroy (ppd.visited);
3120 return error_mark_node;
3123 if (TREE_VALUE (arg) != void_type_node)
3125 /* Collect the sets of parameter packs used in each of the
3126 initialization arguments. */
3127 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3129 /* Determine which parameter packs will be expanded in this
3131 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3136 pointer_set_destroy (ppd.visited);
3138 /* Create the pack expansion type for the base type. */
3139 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3140 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3141 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3143 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3144 they will rarely be compared to anything. */
3145 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3147 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3150 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3153 /* Build the PACK_EXPANSION_* node. */
3155 ? cxx_make_type (TYPE_PACK_EXPANSION)
3156 : make_node (EXPR_PACK_EXPANSION);
3157 SET_PACK_EXPANSION_PATTERN (result, arg);
3158 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3160 /* Propagate type and const-expression information. */
3161 TREE_TYPE (result) = TREE_TYPE (arg);
3162 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3165 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3166 they will rarely be compared to anything. */
3167 SET_TYPE_STRUCTURAL_EQUALITY (result);
3169 /* Determine which parameter packs will be expanded. */
3170 ppd.parameter_packs = ¶meter_packs;
3171 ppd.visited = pointer_set_create ();
3172 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3173 pointer_set_destroy (ppd.visited);
3175 /* Make sure we found some parameter packs. */
3176 if (parameter_packs == NULL_TREE)
3179 error ("expansion pattern %<%T%> contains no argument packs", arg);
3181 error ("expansion pattern %<%E%> contains no argument packs", arg);
3182 return error_mark_node;
3184 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3189 /* Checks T for any "bare" parameter packs, which have not yet been
3190 expanded, and issues an error if any are found. This operation can
3191 only be done on full expressions or types (e.g., an expression
3192 statement, "if" condition, etc.), because we could have expressions like:
3194 foo(f(g(h(args)))...)
3196 where "args" is a parameter pack. check_for_bare_parameter_packs
3197 should not be called for the subexpressions args, h(args),
3198 g(h(args)), or f(g(h(args))), because we would produce erroneous
3201 Returns TRUE and emits an error if there were bare parameter packs,
3202 returns FALSE otherwise. */
3204 check_for_bare_parameter_packs (tree t)
3206 tree parameter_packs = NULL_TREE;
3207 struct find_parameter_pack_data ppd;
3209 if (!processing_template_decl || !t || t == error_mark_node)
3212 if (TREE_CODE (t) == TYPE_DECL)
3215 ppd.parameter_packs = ¶meter_packs;
3216 ppd.visited = pointer_set_create ();
3217 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3218 pointer_set_destroy (ppd.visited);
3220 if (parameter_packs)
3222 error ("parameter packs not expanded with %<...%>:");
3223 while (parameter_packs)
3225 tree pack = TREE_VALUE (parameter_packs);
3226 tree name = NULL_TREE;
3228 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3229 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3230 name = TYPE_NAME (pack);
3231 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3232 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3234 name = DECL_NAME (pack);
3237 inform (input_location, " %qD", name);
3239 inform (input_location, " <anonymous>");
3241 parameter_packs = TREE_CHAIN (parameter_packs);
3250 /* Expand any parameter packs that occur in the template arguments in
3253 expand_template_argument_pack (tree args)
3255 tree result_args = NULL_TREE;
3256 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3257 int num_result_args = -1;
3258 int non_default_args_count = -1;
3260 /* First, determine if we need to expand anything, and the number of
3261 slots we'll need. */
3262 for (in_arg = 0; in_arg < nargs; ++in_arg)
3264 tree arg = TREE_VEC_ELT (args, in_arg);
3265 if (arg == NULL_TREE)
3267 if (ARGUMENT_PACK_P (arg))
3269 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3270 if (num_result_args < 0)
3271 num_result_args = in_arg + num_packed;
3273 num_result_args += num_packed;
3277 if (num_result_args >= 0)
3282 /* If no expansion is necessary, we're done. */
3283 if (num_result_args < 0)
3286 /* Expand arguments. */
3287 result_args = make_tree_vec (num_result_args);
3288 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3289 non_default_args_count =
3290 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3291 for (in_arg = 0; in_arg < nargs; ++in_arg)
3293 tree arg = TREE_VEC_ELT (args, in_arg);
3294 if (ARGUMENT_PACK_P (arg))
3296 tree packed = ARGUMENT_PACK_ARGS (arg);
3297 int i, num_packed = TREE_VEC_LENGTH (packed);
3298 for (i = 0; i < num_packed; ++i, ++out_arg)
3299 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3300 if (non_default_args_count > 0)
3301 non_default_args_count += num_packed;
3305 TREE_VEC_ELT (result_args, out_arg) = arg;
3309 if (non_default_args_count >= 0)
3310 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3314 /* Checks if DECL shadows a template parameter.
3316 [temp.local]: A template-parameter shall not be redeclared within its
3317 scope (including nested scopes).
3319 Emits an error and returns TRUE if the DECL shadows a parameter,
3320 returns FALSE otherwise. */
3323 check_template_shadow (tree decl)
3327 /* If we're not in a template, we can't possibly shadow a template
3329 if (!current_template_parms)
3332 /* Figure out what we're shadowing. */
3333 if (TREE_CODE (decl) == OVERLOAD)
3334 decl = OVL_CURRENT (decl);
3335 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3337 /* If there's no previous binding for this name, we're not shadowing
3338 anything, let alone a template parameter. */
3342 /* If we're not shadowing a template parameter, we're done. Note
3343 that OLDDECL might be an OVERLOAD (or perhaps even an
3344 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3346 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3349 /* We check for decl != olddecl to avoid bogus errors for using a
3350 name inside a class. We check TPFI to avoid duplicate errors for
3351 inline member templates. */
3353 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3356 error ("declaration of %q+#D", decl);
3357 error (" shadows template parm %q+#D", olddecl);
3361 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3362 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3363 template parameters. */
3366 build_template_parm_index (int index,
3373 tree t = make_node (TEMPLATE_PARM_INDEX);
3374 TEMPLATE_PARM_IDX (t) = index;
3375 TEMPLATE_PARM_LEVEL (t) = level;
3376 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3377 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3378 TEMPLATE_PARM_DECL (t) = decl;
3379 TREE_TYPE (t) = type;
3380 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3381 TREE_READONLY (t) = TREE_READONLY (decl);
3386 /* Find the canonical type parameter for the given template type
3387 parameter. Returns the canonical type parameter, which may be TYPE
3388 if no such parameter existed. */
3391 canonical_type_parameter (tree type)
3394 int idx = TEMPLATE_TYPE_IDX (type);
3395 if (!canonical_template_parms)
3396 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3398 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3399 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3401 list = VEC_index (tree, canonical_template_parms, idx);
3402 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3403 list = TREE_CHAIN (list);
3406 return TREE_VALUE (list);
3409 VEC_replace(tree, canonical_template_parms, idx,
3410 tree_cons (NULL_TREE, type,
3411 VEC_index (tree, canonical_template_parms, idx)));
3416 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3417 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3418 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3419 new one is created. */
3422 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3423 tsubst_flags_t complain)
3425 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3426 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3427 != TEMPLATE_PARM_LEVEL (index) - levels)
3428 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3430 tree orig_decl = TEMPLATE_PARM_DECL (index);
3433 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3434 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3435 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3436 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3437 DECL_ARTIFICIAL (decl) = 1;
3438 SET_DECL_TEMPLATE_PARM_P (decl);
3440 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3441 TEMPLATE_PARM_LEVEL (index) - levels,
3442 TEMPLATE_PARM_ORIG_LEVEL (index),
3443 TEMPLATE_PARM_NUM_SIBLINGS (index),
3445 TEMPLATE_PARM_DESCENDANTS (index) = t;
3446 TEMPLATE_PARM_PARAMETER_PACK (t)
3447 = TEMPLATE_PARM_PARAMETER_PACK (index);
3449 /* Template template parameters need this. */
3450 if (TREE_CODE (decl) == TEMPLATE_DECL)
3451 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3452 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3456 return TEMPLATE_PARM_DESCENDANTS (index);
3459 /* Process information from new template parameter PARM and append it
3460 to the LIST being built. This new parameter is a non-type
3461 parameter iff IS_NON_TYPE is true. This new parameter is a
3462 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3463 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3464 parameter list PARM belongs to. This is used used to create a
3465 proper canonical type for the type of PARM that is to be created,
3466 iff PARM is a type. If the size is not known, this parameter shall
3470 process_template_parm (tree list, location_t parm_loc, tree parm,
3471 bool is_non_type, bool is_parameter_pack,
3472 unsigned num_template_parms)
3479 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3480 defval = TREE_PURPOSE (parm);
3484 tree p = tree_last (list);
3486 if (p && TREE_VALUE (p) != error_mark_node)
3489 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3490 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3492 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3502 parm = TREE_VALUE (parm);
3504 SET_DECL_TEMPLATE_PARM_P (parm);
3506 if (TREE_TYPE (parm) == error_mark_node)
3508 err_parm_list = build_tree_list (defval, parm);
3509 TREE_VALUE (err_parm_list) = error_mark_node;
3510 return chainon (list, err_parm_list);
3516 The top-level cv-qualifiers on the template-parameter are
3517 ignored when determining its type. */
3518 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3519 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3521 err_parm_list = build_tree_list (defval, parm);
3522 TREE_VALUE (err_parm_list) = error_mark_node;
3523 return chainon (list, err_parm_list);
3526 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3528 /* This template parameter is not a parameter pack, but it
3529 should be. Complain about "bare" parameter packs. */
3530 check_for_bare_parameter_packs (TREE_TYPE (parm));
3532 /* Recover by calling this a parameter pack. */
3533 is_parameter_pack = true;
3537 /* A template parameter is not modifiable. */
3538 TREE_CONSTANT (parm) = 1;
3539 TREE_READONLY (parm) = 1;
3540 decl = build_decl (parm_loc,
3541 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3542 TREE_CONSTANT (decl) = 1;
3543 TREE_READONLY (decl) = 1;
3544 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3545 = build_template_parm_index (idx, processing_template_decl,
3546 processing_template_decl,
3548 decl, TREE_TYPE (parm));
3550 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3551 = is_parameter_pack;
3556 parm = TREE_VALUE (TREE_VALUE (parm));
3558 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3560 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3561 /* This is for distinguishing between real templates and template
3562 template parameters */
3563 TREE_TYPE (parm) = t;
3564 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3569 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3570 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3571 decl = build_decl (parm_loc,
3572 TYPE_DECL, parm, t);
3575 TYPE_NAME (t) = decl;
3576 TYPE_STUB_DECL (t) = decl;
3578 TEMPLATE_TYPE_PARM_INDEX (t)
3579 = build_template_parm_index (idx, processing_template_decl,
3580 processing_template_decl,
3582 decl, TREE_TYPE (parm));
3583 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3584 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3586 DECL_ARTIFICIAL (decl) = 1;
3587 SET_DECL_TEMPLATE_PARM_P (decl);
3589 parm = build_tree_list (defval, parm);
3590 return chainon (list, parm);
3593 /* The end of a template parameter list has been reached. Process the
3594 tree list into a parameter vector, converting each parameter into a more
3595 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3599 end_template_parm_list (tree parms)
3603 tree saved_parmlist = make_tree_vec (list_length (parms));
3605 current_template_parms
3606 = tree_cons (size_int (processing_template_decl),
3607 saved_parmlist, current_template_parms);
3609 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3611 next = TREE_CHAIN (parm);
3612 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3613 TREE_CHAIN (parm) = NULL_TREE;
3616 fixup_template_parms ();
3618 --processing_template_parmlist;
3620 return saved_parmlist;
3623 /* Create a new type almost identical to TYPE but which has the
3624 following differences:
3626 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3627 template sibling parameters of T.
3629 2/ T has a new canonical type that matches the new number
3632 3/ From now on, T is going to be what lookups referring to the
3633 name of TYPE will return. No lookup should return TYPE anymore.
3635 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3637 This is a subroutine of fixup_template_parms. */
3640 fixup_template_type_parm_type (tree type, int num_parms)
3642 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3644 /* This is the decl which name is inserted into the symbol table for
3645 the template parm type. So whenever we lookup the type name, this
3646 is the DECL we get. */
3649 /* Do not fix up the type twice. */
3650 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3653 t = copy_type (type);
3654 decl = TYPE_NAME (t);
3656 TYPE_MAIN_VARIANT (t) = t;
3657 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3658 TYPE_POINTER_TO (t) = 0;
3659 TYPE_REFERENCE_TO (t) = 0;
3661 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3662 TEMPLATE_PARM_LEVEL (orig_idx),
3663 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3666 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3667 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3668 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3670 TYPE_STUB_DECL (t) = decl;
3671 TEMPLATE_TYPE_DECL (t) = decl;
3672 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3673 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3675 /* Update the type associated to the type name stored in the symbol
3676 table. Now, whenever the type name is looked up, the resulting
3677 type is properly fixed up. */
3678 TREE_TYPE (decl) = t;
3680 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3685 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3686 identical to I, but that is fixed up as to:
3688 1/ carry the number of sibling parms (NUM_PARMS) of the template
3689 parm represented by I.
3691 2/ replace all references to template parm types declared before I
3692 (in the same template parm list as I) by references to template
3693 parm types contained in ARGS. ARGS should contain the list of
3694 template parms that have been fixed up so far, in a form suitable
3695 to be passed to tsubst.
3697 This is a subroutine of fixup_template_parms. */
3700 fixup_template_parm_index (tree i, tree args, int num_parms)
3702 tree index, decl, type;
3705 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3706 /* Do not fix up the index twice. */
3707 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3710 decl = TEMPLATE_PARM_DECL (i);
3711 type = TREE_TYPE (decl);
3713 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3714 TEMPLATE_PARM_LEVEL (i),
3715 TEMPLATE_PARM_ORIG_LEVEL (i),
3719 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3720 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3722 type = tsubst (type, args, tf_none, NULL_TREE);
3724 TREE_TYPE (decl) = type;
3725 TREE_TYPE (index) = type;
3731 This is a subroutine of fixup_template_parms.
3733 It computes the canonical type of the type of the template
3734 parameter PARM_DESC and update all references to that type so that
3735 they use the newly computed canonical type. No access check is
3736 performed during the fixup. PARM_DESC is a TREE_LIST which
3737 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3738 default argument of the template parm if any. IDX is the index of
3739 the template parameter, starting at 0. NUM_PARMS is the number of
3740 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3741 TREE_VEC containing the full set of template parameters in a form
3742 suitable to be passed to substs functions as their ARGS
3743 argument. This is what current_template_args returns for a given
3744 template. The innermost vector of args in ARGLIST is the set of
3745 template parms that have been fixed up so far. This function adds
3746 the fixed up parameter into that vector. */
3749 fixup_template_parm (tree parm_desc,
3754 tree parm = TREE_VALUE (parm_desc);
3755 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3757 push_deferring_access_checks (dk_no_check);
3759 if (TREE_CODE (parm) == TYPE_DECL)
3761 /* PARM is a template type parameter. Fix up its type, add
3762 the fixed-up template parm to the vector of fixed-up
3763 template parms so far, and substitute the fixed-up
3764 template parms into the default argument of this
3767 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3768 TREE_TYPE (parm) = t;
3770 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3772 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3774 /* PARM is a template template parameter. This is going to
3776 tree tparms, targs, innermost_args;
3779 /* First, fix up the type of the parm. */
3782 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3783 TREE_TYPE (parm) = t;
3785 TREE_VEC_ELT (fixedup_args, idx) =
3786 template_parm_to_arg (parm_desc);
3788 /* Now we need to substitute the template parm types that
3789 have been fixed up so far into the non-type template
3790 parms of this template template parm. E.g, consider this:
3792 template<class T, template<T u> class TT> class S;
3794 In this case we want to substitute T into the
3795 template parameters of TT.
3797 So let's walk the template parms of PARM here, and
3798 tsubst ARGLIST into into each of the template
3801 /* For this substitution we need to build the full set of
3802 template parameters and use that as arguments for the
3803 tsubsting function. */
3804 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3806 /* This will contain the innermost parms of PARM into which
3807 we have substituted so far. */
3808 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3809 targs = add_to_template_args (arglist, innermost_args);
3810 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3814 parameter = TREE_VEC_ELT (tparms, j);
3816 /* INNERMOST_ARGS needs to have at least the same number
3817 of elements as the index PARAMETER, ortherwise
3818 tsubsting into PARAMETER will result in partially
3819 instantiating it, reducing its tempate parm
3820 level. Let's tactically fill INNERMOST_ARGS for that
3822 TREE_VEC_ELT (innermost_args, j) =
3823 template_parm_to_arg (parameter);
3825 fixup_template_parm (parameter, j,
3826 TREE_VEC_LENGTH (tparms),
3830 else if (TREE_CODE (parm) == PARM_DECL)
3832 /* PARM is a non-type template parameter. We need to:
3834 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3835 proper number of sibling parameters.
3837 * Make lookups of the template parameter return a reference
3838 to the fixed-up index. No lookup should return references
3839 to the former index anymore.
3841 * Substitute the template parms that got fixed up so far
3843 * into the type of PARM. */
3845 tree index = DECL_INITIAL (parm);
3847 /* PUSHED_DECL is the decl added to the symbol table with
3848 the name of the parameter. E,g:
3850 template<class T, T u> //#0
3851 auto my_function(T t) -> decltype(u); //#1
3853 Here, when looking up u at //#1, we get the decl of u
3854 resulting from the declaration in #0. This is what
3855 PUSHED_DECL is. We need to replace the reference to the
3856 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3857 fixed-up TEMPLATE_PARM_INDEX. */
3858 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3860 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3861 fixup the type of PUSHED_DECL as well and luckily
3862 fixup_template_parm_index does it for us too. */
3863 tree fixed_up_index =
3864 fixup_template_parm_index (index, arglist, num_parms);
3866 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3868 /* Add this fixed up PARM to the template parms we've fixed
3869 up so far and use that to substitute the fixed-up
3870 template parms into the type of PARM. */
3871 TREE_VEC_ELT (fixedup_args, idx) =
3872 template_parm_to_arg (parm_desc);
3873 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3874 tf_none, NULL_TREE);
3877 TREE_PURPOSE (parm_desc) =
3878 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3879 arglist, tf_none, parm);
3881 pop_deferring_access_checks ();
3884 /* Walk current the template parms and properly compute the canonical
3885 types of the dependent types created during
3886 cp_parser_template_parameter_list. */
3889 fixup_template_parms (void)
3896 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3897 if (parameter_vec == NULL_TREE)
3900 num_parms = TREE_VEC_LENGTH (parameter_vec);
3902 /* This vector contains the current innermost template parms that
3903 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3904 to be passed to tsubst* functions as their ARGS argument. */
3905 fixedup_args = make_tree_vec (num_parms);
3907 /* This vector contains the full set of template parms in a form
3908 suitable to be passed to substs functions as their ARGS
3910 arglist = current_template_args ();
3911 arglist = add_outermost_template_args (arglist, fixedup_args);
3913 fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3915 /* Let's do the proper fixup now. */
3916 for (i = 0; i < num_parms; ++i)
3917 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3918 i, num_parms, arglist);
3921 /* end_template_decl is called after a template declaration is seen. */
3924 end_template_decl (void)
3926 reset_specialization ();
3928 if (! processing_template_decl)
3931 /* This matches the pushlevel in begin_template_parm_list. */
3934 --processing_template_decl;
3935 current_template_parms = TREE_CHAIN (current_template_parms);
3938 /* Takes a TREE_LIST representing a template parameter and convert it
3939 into an argument suitable to be passed to the type substitution
3940 functions. Note that If the TREE_LIST contains an error_mark
3941 node, the returned argument is error_mark_node. */
3944 template_parm_to_arg (tree t)
3948 || TREE_CODE (t) != TREE_LIST)
3951 if (error_operand_p (TREE_VALUE (t)))
3952 return error_mark_node;
3956 if (TREE_CODE (t) == TYPE_DECL
3957 || TREE_CODE (t) == TEMPLATE_DECL)
3961 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3963 /* Turn this argument into a TYPE_ARGUMENT_PACK
3964 with a single element, which expands T. */
3965 tree vec = make_tree_vec (1);
3966 #ifdef ENABLE_CHECKING
3967 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3968 (vec, TREE_VEC_LENGTH (vec));
3970 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3972 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3973 SET_ARGUMENT_PACK_ARGS (t, vec);
3978 t = DECL_INITIAL (t);
3980 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3982 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3983 with a single element, which expands T. */
3984 tree vec = make_tree_vec (1);
3985 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3986 #ifdef ENABLE_CHECKING
3987 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3988 (vec, TREE_VEC_LENGTH (vec));
3990 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3992 t = make_node (NONTYPE_ARGUMENT_PACK);
3993 SET_ARGUMENT_PACK_ARGS (t, vec);
3994 TREE_TYPE (t) = type;
4000 /* Within the declaration of a template, return all levels of template
4001 parameters that apply. The template parameters are represented as
4002 a TREE_VEC, in the form documented in cp-tree.h for template
4006 current_template_args (void)
4009 tree args = NULL_TREE;
4010 int length = TMPL_PARMS_DEPTH (current_template_parms);
4013 /* If there is only one level of template parameters, we do not
4014 create a TREE_VEC of TREE_VECs. Instead, we return a single
4015 TREE_VEC containing the arguments. */
4017 args = make_tree_vec (length);
4019 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4021 tree a = copy_node (TREE_VALUE (header));
4024 TREE_TYPE (a) = NULL_TREE;
4025 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4026 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4028 #ifdef ENABLE_CHECKING
4029 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4033 TREE_VEC_ELT (args, --l) = a;
4038 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4039 /* This can happen for template parms of a template template
4042 template<template<class T, class U> class TT> struct S;
4044 Consider the level of the parms of TT; T and U both have
4045 level 2; TT has no template parm of level 1. So in this case
4046 the first element of full_template_args is NULL_TREE. If we
4047 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4048 of 2. This will make tsubst wrongly consider that T and U
4049 have level 1. Instead, let's create a dummy vector as the
4050 first element of full_template_args so that TMPL_ARG_DEPTH
4051 returns the correct depth for args. */
4052 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4056 /* Update the declared TYPE by doing any lookups which were thought to be
4057 dependent, but are not now that we know the SCOPE of the declarator. */
4060 maybe_update_decl_type (tree orig_type, tree scope)
4062 tree type = orig_type;
4064 if (type == NULL_TREE)
4067 if (TREE_CODE (orig_type) == TYPE_DECL)
4068 type = TREE_TYPE (type);
4070 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4071 && dependent_type_p (type)
4072 /* Don't bother building up the args in this case. */
4073 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4075 /* tsubst in the args corresponding to the template parameters,
4076 including auto if present. Most things will be unchanged, but
4077 make_typename_type and tsubst_qualified_id will resolve
4078 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4079 tree args = current_template_args ();
4080 tree auto_node = type_uses_auto (type);
4084 tree auto_vec = make_tree_vec (1);
4085 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4086 args = add_to_template_args (args, auto_vec);
4088 pushed = push_scope (scope);
4089 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4094 if (type == error_mark_node)
4097 if (TREE_CODE (orig_type) == TYPE_DECL)
4099 if (same_type_p (type, TREE_TYPE (orig_type)))
4102 type = TYPE_NAME (type);
4107 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4108 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4109 a member template. Used by push_template_decl below. */
4112 build_template_decl (tree decl, tree parms, bool member_template_p)
4114 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4115 DECL_TEMPLATE_PARMS (tmpl) = parms;
4116 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4117 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4122 struct template_parm_data
4124 /* The level of the template parameters we are currently
4128 /* The index of the specialization argument we are currently
4132 /* An array whose size is the number of template parameters. The
4133 elements are nonzero if the parameter has been used in any one
4134 of the arguments processed so far. */
4137 /* An array whose size is the number of template arguments. The
4138 elements are nonzero if the argument makes use of template
4139 parameters of this level. */
4140 int* arg_uses_template_parms;
4143 /* Subroutine of push_template_decl used to see if each template
4144 parameter in a partial specialization is used in the explicit
4145 argument list. If T is of the LEVEL given in DATA (which is
4146 treated as a template_parm_data*), then DATA->PARMS is marked
4150 mark_template_parm (tree t, void* data)
4154 struct template_parm_data* tpd = (struct template_parm_data*) data;
4156 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4158 level = TEMPLATE_PARM_LEVEL (t);
4159 idx = TEMPLATE_PARM_IDX (t);
4163 level = TEMPLATE_TYPE_LEVEL (t);
4164 idx = TEMPLATE_TYPE_IDX (t);
4167 if (level == tpd->level)
4169 tpd->parms[idx] = 1;
4170 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4173 /* Return zero so that for_each_template_parm will continue the
4174 traversal of the tree; we want to mark *every* template parm. */
4178 /* Process the partial specialization DECL. */
4181 process_partial_specialization (tree decl)
4183 tree type = TREE_TYPE (decl);
4184 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4185 tree specargs = CLASSTYPE_TI_ARGS (type);
4186 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4187 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4190 int nargs = TREE_VEC_LENGTH (inner_args);
4193 bool did_error_intro = false;
4194 struct template_parm_data tpd;
4195 struct template_parm_data tpd2;
4197 gcc_assert (current_template_parms);
4199 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4200 ntparms = TREE_VEC_LENGTH (inner_parms);
4202 /* We check that each of the template parameters given in the
4203 partial specialization is used in the argument list to the
4204 specialization. For example:
4206 template <class T> struct S;
4207 template <class T> struct S<T*>;
4209 The second declaration is OK because `T*' uses the template
4210 parameter T, whereas
4212 template <class T> struct S<int>;
4214 is no good. Even trickier is:
4225 The S2<T> declaration is actually invalid; it is a
4226 full-specialization. Of course,
4229 struct S2<T (*)(U)>;
4231 or some such would have been OK. */
4232 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4233 tpd.parms = XALLOCAVEC (int, ntparms);
4234 memset (tpd.parms, 0, sizeof (int) * ntparms);
4236 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4237 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4238 for (i = 0; i < nargs; ++i)
4240 tpd.current_arg = i;
4241 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4242 &mark_template_parm,
4245 /*include_nondeduced_p=*/false);
4247 for (i = 0; i < ntparms; ++i)
4248 if (tpd.parms[i] == 0)
4250 /* One of the template parms was not used in the
4252 if (!did_error_intro)
4254 error ("template parameters not used in partial specialization:");
4255 did_error_intro = true;
4258 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4261 if (did_error_intro)
4262 return error_mark_node;
4264 /* [temp.class.spec]
4266 The argument list of the specialization shall not be identical to
4267 the implicit argument list of the primary template. */
4268 if (comp_template_args
4270 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4272 error ("partial specialization %qT does not specialize any template arguments", type);
4274 /* [temp.class.spec]
4276 A partially specialized non-type argument expression shall not
4277 involve template parameters of the partial specialization except
4278 when the argument expression is a simple identifier.
4280 The type of a template parameter corresponding to a specialized
4281 non-type argument shall not be dependent on a parameter of the
4284 Also, we verify that pack expansions only occur at the
4285 end of the argument list. */
4286 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4288 for (i = 0; i < nargs; ++i)
4290 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4291 tree arg = TREE_VEC_ELT (inner_args, i);
4292 tree packed_args = NULL_TREE;
4295 if (ARGUMENT_PACK_P (arg))
4297 /* Extract the arguments from the argument pack. We'll be
4298 iterating over these in the following loop. */
4299 packed_args = ARGUMENT_PACK_ARGS (arg);
4300 len = TREE_VEC_LENGTH (packed_args);
4303 for (j = 0; j < len; j++)
4306 /* Get the Jth argument in the parameter pack. */
4307 arg = TREE_VEC_ELT (packed_args, j);
4309 if (PACK_EXPANSION_P (arg))
4311 /* Pack expansions must come at the end of the
4313 if ((packed_args && j < len - 1)
4314 || (!packed_args && i < nargs - 1))
4316 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4317 error ("parameter pack argument %qE must be at the "
4318 "end of the template argument list", arg);
4320 error ("parameter pack argument %qT must be at the "
4321 "end of the template argument list", arg);
4325 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4326 /* We only care about the pattern. */
4327 arg = PACK_EXPANSION_PATTERN (arg);
4329 if (/* These first two lines are the `non-type' bit. */
4331 && TREE_CODE (arg) != TEMPLATE_DECL
4332 /* This next line is the `argument expression is not just a
4333 simple identifier' condition and also the `specialized
4334 non-type argument' bit. */
4335 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4337 if ((!packed_args && tpd.arg_uses_template_parms[i])
4338 || (packed_args && uses_template_parms (arg)))
4339 error ("template argument %qE involves template parameter(s)",
4343 /* Look at the corresponding template parameter,
4344 marking which template parameters its type depends
4346 tree type = TREE_TYPE (parm);
4350 /* We haven't yet initialized TPD2. Do so now. */
4351 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4352 /* The number of parameters here is the number in the
4353 main template, which, as checked in the assertion
4355 tpd2.parms = XALLOCAVEC (int, nargs);
4357 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4360 /* Mark the template parameters. But this time, we're
4361 looking for the template parameters of the main
4362 template, not in the specialization. */
4363 tpd2.current_arg = i;
4364 tpd2.arg_uses_template_parms[i] = 0;
4365 memset (tpd2.parms, 0, sizeof (int) * nargs);
4366 for_each_template_parm (type,
4367 &mark_template_parm,
4370 /*include_nondeduced_p=*/false);
4372 if (tpd2.arg_uses_template_parms [i])
4374 /* The type depended on some template parameters.
4375 If they are fully specialized in the
4376 specialization, that's OK. */
4379 for (j = 0; j < nargs; ++j)
4380 if (tpd2.parms[j] != 0
4381 && tpd.arg_uses_template_parms [j])
4384 error_n (input_location, count,
4385 "type %qT of template argument %qE depends "
4386 "on a template parameter",
4387 "type %qT of template argument %qE depends "
4388 "on template parameters",
4397 /* We should only get here once. */
4398 gcc_assert (!COMPLETE_TYPE_P (type));
4400 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4401 = tree_cons (specargs, inner_parms,
4402 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4403 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4405 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4406 inst = TREE_CHAIN (inst))
4408 tree inst_type = TREE_VALUE (inst);
4409 if (COMPLETE_TYPE_P (inst_type)
4410 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4412 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4413 if (spec && TREE_TYPE (spec) == type)
4414 permerror (input_location,
4415 "partial specialization of %qT after instantiation "
4416 "of %qT", type, inst_type);
4423 /* Check that a template declaration's use of default arguments and
4424 parameter packs is not invalid. Here, PARMS are the template
4425 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4426 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4430 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4431 declaration (but not a definition); 1 indicates a declaration, 2
4432 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4433 emitted for extraneous default arguments.
4435 Returns TRUE if there were no errors found, FALSE otherwise. */
4438 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4439 int is_partial, int is_friend_decl)
4442 int last_level_to_check;
4444 bool no_errors = true;
4448 A default template-argument shall not be specified in a
4449 function template declaration or a function template definition, nor
4450 in the template-parameter-list of the definition of a member of a
4453 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4454 /* You can't have a function template declaration in a local
4455 scope, nor you can you define a member of a class template in a
4459 if (current_class_type
4460 && !TYPE_BEING_DEFINED (current_class_type)
4461 && DECL_LANG_SPECIFIC (decl)
4462 && DECL_DECLARES_FUNCTION_P (decl)
4463 /* If this is either a friend defined in the scope of the class
4464 or a member function. */
4465 && (DECL_FUNCTION_MEMBER_P (decl)
4466 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4467 : DECL_FRIEND_CONTEXT (decl)
4468 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4470 /* And, if it was a member function, it really was defined in
4471 the scope of the class. */
4472 && (!DECL_FUNCTION_MEMBER_P (decl)
4473 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4474 /* We already checked these parameters when the template was
4475 declared, so there's no need to do it again now. This function
4476 was defined in class scope, but we're processing it's body now
4477 that the class is complete. */
4480 /* Core issue 226 (C++0x only): the following only applies to class
4482 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4486 If a template-parameter has a default template-argument, all
4487 subsequent template-parameters shall have a default
4488 template-argument supplied. */
4489 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4491 tree inner_parms = TREE_VALUE (parm_level);
4492 int ntparms = TREE_VEC_LENGTH (inner_parms);
4493 int seen_def_arg_p = 0;
4496 for (i = 0; i < ntparms; ++i)
4498 tree parm = TREE_VEC_ELT (inner_parms, i);
4500 if (parm == error_mark_node)
4503 if (TREE_PURPOSE (parm))
4505 else if (seen_def_arg_p
4506 && !template_parameter_pack_p (TREE_VALUE (parm)))
4508 error ("no default argument for %qD", TREE_VALUE (parm));
4509 /* For better subsequent error-recovery, we indicate that
4510 there should have been a default argument. */
4511 TREE_PURPOSE (parm) = error_mark_node;
4517 /* Don't complain about an enclosing partial
4519 && parm_level == parms
4520 && TREE_CODE (decl) == TYPE_DECL
4522 && template_parameter_pack_p (TREE_VALUE (parm)))
4524 /* A primary class template can only have one
4525 parameter pack, at the end of the template
4528 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4529 error ("parameter pack %qE must be at the end of the"
4530 " template parameter list", TREE_VALUE (parm));
4532 error ("parameter pack %qT must be at the end of the"
4533 " template parameter list",
4534 TREE_TYPE (TREE_VALUE (parm)));
4536 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4544 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4548 /* For an ordinary class template, default template arguments are
4549 allowed at the innermost level, e.g.:
4550 template <class T = int>
4552 but, in a partial specialization, they're not allowed even
4553 there, as we have in [temp.class.spec]:
4555 The template parameter list of a specialization shall not
4556 contain default template argument values.
4558 So, for a partial specialization, or for a function template
4559 (in C++98/C++03), we look at all of them. */
4562 /* But, for a primary class template that is not a partial
4563 specialization we look at all template parameters except the
4565 parms = TREE_CHAIN (parms);
4567 /* Figure out what error message to issue. */
4568 if (is_friend_decl == 2)
4569 msg = G_("default template arguments may not be used in function template "
4570 "friend re-declaration");
4571 else if (is_friend_decl)
4572 msg = G_("default template arguments may not be used in function template "
4573 "friend declarations");
4574 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4575 msg = G_("default template arguments may not be used in function templates "
4576 "without -std=c++0x or -std=gnu++0x");
4577 else if (is_partial)
4578 msg = G_("default template arguments may not be used in "
4579 "partial specializations");
4581 msg = G_("default argument for template parameter for class enclosing %qD");
4583 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4584 /* If we're inside a class definition, there's no need to
4585 examine the parameters to the class itself. On the one
4586 hand, they will be checked when the class is defined, and,
4587 on the other, default arguments are valid in things like:
4588 template <class T = double>
4589 struct S { template <class U> void f(U); };
4590 Here the default argument for `S' has no bearing on the
4591 declaration of `f'. */
4592 last_level_to_check = template_class_depth (current_class_type) + 1;
4594 /* Check everything. */
4595 last_level_to_check = 0;
4597 for (parm_level = parms;
4598 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4599 parm_level = TREE_CHAIN (parm_level))
4601 tree inner_parms = TREE_VALUE (parm_level);
4605 ntparms = TREE_VEC_LENGTH (inner_parms);
4606 for (i = 0; i < ntparms; ++i)
4608 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4611 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4616 if (is_friend_decl == 2)
4623 /* Clear out the default argument so that we are not
4625 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4629 /* At this point, if we're still interested in issuing messages,
4630 they must apply to classes surrounding the object declared. */
4632 msg = G_("default argument for template parameter for class "
4639 /* Worker for push_template_decl_real, called via
4640 for_each_template_parm. DATA is really an int, indicating the
4641 level of the parameters we are interested in. If T is a template
4642 parameter of that level, return nonzero. */
4645 template_parm_this_level_p (tree t, void* data)
4647 int this_level = *(int *)data;
4650 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4651 level = TEMPLATE_PARM_LEVEL (t);
4653 level = TEMPLATE_TYPE_LEVEL (t);
4654 return level == this_level;
4657 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4658 parameters given by current_template_args, or reuses a
4659 previously existing one, if appropriate. Returns the DECL, or an
4660 equivalent one, if it is replaced via a call to duplicate_decls.
4662 If IS_FRIEND is true, DECL is a friend declaration. */
4665 push_template_decl_real (tree decl, bool is_friend)
4673 int new_template_p = 0;
4674 /* True if the template is a member template, in the sense of
4676 bool member_template_p = false;
4678 if (decl == error_mark_node || !current_template_parms)
4679 return error_mark_node;
4681 /* See if this is a partial specialization. */
4682 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4683 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4684 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4686 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4690 /* For a friend, we want the context of the friend function, not
4691 the type of which it is a friend. */
4692 ctx = CP_DECL_CONTEXT (decl);
4693 else if (CP_DECL_CONTEXT (decl)
4694 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4695 /* In the case of a virtual function, we want the class in which
4697 ctx = CP_DECL_CONTEXT (decl);
4699 /* Otherwise, if we're currently defining some class, the DECL
4700 is assumed to be a member of the class. */
4701 ctx = current_scope ();
4703 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4706 if (!DECL_CONTEXT (decl))
4707 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4709 /* See if this is a primary template. */
4710 if (is_friend && ctx)
4711 /* A friend template that specifies a class context, i.e.
4712 template <typename T> friend void A<T>::f();
4716 primary = template_parm_scope_p ();
4720 if (DECL_CLASS_SCOPE_P (decl))
4721 member_template_p = true;
4722 if (TREE_CODE (decl) == TYPE_DECL
4723 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4725 error ("template class without a name");
4726 return error_mark_node;
4728 else if (TREE_CODE (decl) == FUNCTION_DECL)
4730 if (DECL_DESTRUCTOR_P (decl))
4734 A destructor shall not be a member template. */
4735 error ("destructor %qD declared as member template", decl);
4736 return error_mark_node;
4738 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4739 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4740 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4741 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4742 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4743 == void_list_node)))
4745 /* [basic.stc.dynamic.allocation]
4747 An allocation function can be a function
4748 template. ... Template allocation functions shall
4749 have two or more parameters. */
4750 error ("invalid template declaration of %qD", decl);
4751 return error_mark_node;
4754 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4755 && CLASS_TYPE_P (TREE_TYPE (decl)))
4759 error ("template declaration of %q#D", decl);
4760 return error_mark_node;
4764 /* Check to see that the rules regarding the use of default
4765 arguments are not being violated. */
4766 check_default_tmpl_args (decl, current_template_parms,
4767 primary, is_partial, /*is_friend_decl=*/0);
4769 /* Ensure that there are no parameter packs in the type of this
4770 declaration that have not been expanded. */
4771 if (TREE_CODE (decl) == FUNCTION_DECL)
4773 /* Check each of the arguments individually to see if there are
4774 any bare parameter packs. */
4775 tree type = TREE_TYPE (decl);
4776 tree arg = DECL_ARGUMENTS (decl);
4777 tree argtype = TYPE_ARG_TYPES (type);
4779 while (arg && argtype)
4781 if (!FUNCTION_PARAMETER_PACK_P (arg)
4782 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4784 /* This is a PARM_DECL that contains unexpanded parameter
4785 packs. We have already complained about this in the
4786 check_for_bare_parameter_packs call, so just replace
4787 these types with ERROR_MARK_NODE. */
4788 TREE_TYPE (arg) = error_mark_node;
4789 TREE_VALUE (argtype) = error_mark_node;
4792 arg = DECL_CHAIN (arg);
4793 argtype = TREE_CHAIN (argtype);
4796 /* Check for bare parameter packs in the return type and the
4797 exception specifiers. */
4798 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4799 /* Errors were already issued, set return type to int
4800 as the frontend doesn't expect error_mark_node as
4802 TREE_TYPE (type) = integer_type_node;
4803 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4804 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4806 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4808 TREE_TYPE (decl) = error_mark_node;
4809 return error_mark_node;
4813 return process_partial_specialization (decl);
4815 args = current_template_args ();
4818 || TREE_CODE (ctx) == FUNCTION_DECL
4819 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4820 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4822 if (DECL_LANG_SPECIFIC (decl)
4823 && DECL_TEMPLATE_INFO (decl)
4824 && DECL_TI_TEMPLATE (decl))
4825 tmpl = DECL_TI_TEMPLATE (decl);
4826 /* If DECL is a TYPE_DECL for a class-template, then there won't
4827 be DECL_LANG_SPECIFIC. The information equivalent to
4828 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4829 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4830 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4831 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4833 /* Since a template declaration already existed for this
4834 class-type, we must be redeclaring it here. Make sure
4835 that the redeclaration is valid. */
4836 redeclare_class_template (TREE_TYPE (decl),
4837 current_template_parms);
4838 /* We don't need to create a new TEMPLATE_DECL; just use the
4839 one we already had. */
4840 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4844 tmpl = build_template_decl (decl, current_template_parms,
4848 if (DECL_LANG_SPECIFIC (decl)
4849 && DECL_TEMPLATE_SPECIALIZATION (decl))
4851 /* A specialization of a member template of a template
4853 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4854 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4855 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4861 tree a, t, current, parms;
4863 tree tinfo = get_template_info (decl);
4867 error ("template definition of non-template %q#D", decl);
4868 return error_mark_node;
4871 tmpl = TI_TEMPLATE (tinfo);
4873 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4874 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4875 && DECL_TEMPLATE_SPECIALIZATION (decl)
4876 && DECL_MEMBER_TEMPLATE_P (tmpl))
4880 /* The declaration is a specialization of a member
4881 template, declared outside the class. Therefore, the
4882 innermost template arguments will be NULL, so we
4883 replace them with the arguments determined by the
4884 earlier call to check_explicit_specialization. */
4885 args = DECL_TI_ARGS (decl);
4888 = build_template_decl (decl, current_template_parms,
4890 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4891 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4892 DECL_TI_TEMPLATE (decl) = new_tmpl;
4893 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4894 DECL_TEMPLATE_INFO (new_tmpl)
4895 = build_template_info (tmpl, args);
4897 register_specialization (new_tmpl,
4898 most_general_template (tmpl),
4904 /* Make sure the template headers we got make sense. */
4906 parms = DECL_TEMPLATE_PARMS (tmpl);
4907 i = TMPL_PARMS_DEPTH (parms);
4908 if (TMPL_ARGS_DEPTH (args) != i)
4910 error ("expected %d levels of template parms for %q#D, got %d",
4911 i, decl, TMPL_ARGS_DEPTH (args));
4914 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4916 a = TMPL_ARGS_LEVEL (args, i);
4917 t = INNERMOST_TEMPLATE_PARMS (parms);
4919 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4921 if (current == decl)
4922 error ("got %d template parameters for %q#D",
4923 TREE_VEC_LENGTH (a), decl);
4925 error ("got %d template parameters for %q#T",
4926 TREE_VEC_LENGTH (a), current);
4927 error (" but %d required", TREE_VEC_LENGTH (t));
4928 return error_mark_node;
4931 if (current == decl)
4933 else if (current == NULL_TREE)
4934 /* Can happen in erroneous input. */
4937 current = (TYPE_P (current)
4938 ? TYPE_CONTEXT (current)
4939 : DECL_CONTEXT (current));
4942 /* Check that the parms are used in the appropriate qualifying scopes
4943 in the declarator. */
4944 if (!comp_template_args
4946 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4949 template arguments to %qD do not match original template %qD",
4950 decl, DECL_TEMPLATE_RESULT (tmpl));
4951 if (!uses_template_parms (TI_ARGS (tinfo)))
4952 inform (input_location, "use template<> for an explicit specialization");
4953 /* Avoid crash in import_export_decl. */
4954 DECL_INTERFACE_KNOWN (decl) = 1;
4955 return error_mark_node;
4959 DECL_TEMPLATE_RESULT (tmpl) = decl;
4960 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4962 /* Push template declarations for global functions and types. Note
4963 that we do not try to push a global template friend declared in a
4964 template class; such a thing may well depend on the template
4965 parameters of the class. */
4966 if (new_template_p && !ctx
4967 && !(is_friend && template_class_depth (current_class_type) > 0))
4969 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4970 if (tmpl == error_mark_node)
4971 return error_mark_node;
4973 /* Hide template friend classes that haven't been declared yet. */
4974 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4976 DECL_ANTICIPATED (tmpl) = 1;
4977 DECL_FRIEND_P (tmpl) = 1;
4983 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4986 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4987 if (DECL_CONV_FN_P (tmpl))
4989 int depth = TMPL_PARMS_DEPTH (parms);
4991 /* It is a conversion operator. See if the type converted to
4992 depends on innermost template operands. */
4994 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4996 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4999 /* Give template template parms a DECL_CONTEXT of the template
5000 for which they are a parameter. */
5001 parms = INNERMOST_TEMPLATE_PARMS (parms);
5002 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5004 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5005 if (TREE_CODE (parm) == TEMPLATE_DECL)
5006 DECL_CONTEXT (parm) = tmpl;
5010 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5011 back to its most general template. If TMPL is a specialization,
5012 ARGS may only have the innermost set of arguments. Add the missing
5013 argument levels if necessary. */
5014 if (DECL_TEMPLATE_INFO (tmpl))
5015 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5017 info = build_template_info (tmpl, args);
5019 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5020 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5021 else if (DECL_LANG_SPECIFIC (decl))
5022 DECL_TEMPLATE_INFO (decl) = info;
5024 return DECL_TEMPLATE_RESULT (tmpl);
5028 push_template_decl (tree decl)
5030 return push_template_decl_real (decl, false);
5033 /* Called when a class template TYPE is redeclared with the indicated
5034 template PARMS, e.g.:
5036 template <class T> struct S;
5037 template <class T> struct S {}; */
5040 redeclare_class_template (tree type, tree parms)
5046 if (!TYPE_TEMPLATE_INFO (type))
5048 error ("%qT is not a template type", type);
5052 tmpl = TYPE_TI_TEMPLATE (type);
5053 if (!PRIMARY_TEMPLATE_P (tmpl))
5054 /* The type is nested in some template class. Nothing to worry
5055 about here; there are no new template parameters for the nested
5061 error ("template specifiers not specified in declaration of %qD",
5066 parms = INNERMOST_TEMPLATE_PARMS (parms);
5067 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5069 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5071 error_n (input_location, TREE_VEC_LENGTH (parms),
5072 "redeclared with %d template parameter",
5073 "redeclared with %d template parameters",
5074 TREE_VEC_LENGTH (parms));
5075 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5076 "previous declaration %q+D used %d template parameter",
5077 "previous declaration %q+D used %d template parameters",
5078 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5082 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5089 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5090 || TREE_VEC_ELT (parms, i) == error_mark_node)
5093 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5094 if (tmpl_parm == error_mark_node)
5097 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5098 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5099 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5101 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5103 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5104 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5105 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5106 || (TREE_CODE (tmpl_parm) != PARM_DECL
5107 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5108 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5109 || (TREE_CODE (tmpl_parm) == PARM_DECL
5110 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5111 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5113 error ("template parameter %q+#D", tmpl_parm);
5114 error ("redeclared here as %q#D", parm);
5118 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5120 /* We have in [temp.param]:
5122 A template-parameter may not be given default arguments
5123 by two different declarations in the same scope. */
5124 error_at (input_location, "redefinition of default argument for %q#D", parm);
5125 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5126 "original definition appeared here");
5130 if (parm_default != NULL_TREE)
5131 /* Update the previous template parameters (which are the ones
5132 that will really count) with the new default value. */
5133 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5134 else if (tmpl_default != NULL_TREE)
5135 /* Update the new parameters, too; they'll be used as the
5136 parameters for any members. */
5137 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5143 /* Simplify EXPR if it is a non-dependent expression. Returns the
5144 (possibly simplified) expression. */
5147 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5149 if (expr == NULL_TREE)
5152 /* If we're in a template, but EXPR isn't value dependent, simplify
5153 it. We're supposed to treat:
5155 template <typename T> void f(T[1 + 1]);
5156 template <typename T> void f(T[2]);
5158 as two declarations of the same function, for example. */
5159 if (processing_template_decl
5160 && !type_dependent_expression_p (expr)
5161 && !value_dependent_expression_p (expr))
5163 HOST_WIDE_INT saved_processing_template_decl;
5165 saved_processing_template_decl = processing_template_decl;
5166 processing_template_decl = 0;
5167 expr = tsubst_copy_and_build (expr,
5170 /*in_decl=*/NULL_TREE,
5171 /*function_p=*/false,
5172 /*integral_constant_expression_p=*/true);
5173 processing_template_decl = saved_processing_template_decl;
5179 fold_non_dependent_expr (tree expr)
5181 return fold_non_dependent_expr_sfinae (expr, tf_error);
5184 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5185 must be a function or a pointer-to-function type, as specified
5186 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5187 and check that the resulting function has external linkage. */
5190 convert_nontype_argument_function (tree type, tree expr)
5195 fn = instantiate_type (type, fns, tf_none);
5196 if (fn == error_mark_node)
5197 return error_mark_node;
5200 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5201 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5202 if (TREE_CODE (fn_no_ptr) == BASELINK)
5203 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5205 /* [temp.arg.nontype]/1
5207 A template-argument for a non-type, non-template template-parameter
5210 -- the address of an object or function with external linkage. */
5211 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5213 error ("%qE is not a valid template argument for type %qT "
5214 "because function %qD has not external linkage",
5215 expr, type, fn_no_ptr);
5222 /* Subroutine of convert_nontype_argument.
5223 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5224 Emit an error otherwise. */
5227 check_valid_ptrmem_cst_expr (tree type, tree expr,
5228 tsubst_flags_t complain)
5231 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5233 if (complain & tf_error)
5235 error ("%qE is not a valid template argument for type %qT",
5237 error ("it must be a pointer-to-member of the form `&X::Y'");
5242 /* Returns TRUE iff the address of OP is value-dependent.
5244 14.6.2.4 [temp.dep.temp]:
5245 A non-integral non-type template-argument is dependent if its type is
5246 dependent or it has either of the following forms
5249 and contains a nested-name-specifier which specifies a class-name that
5250 names a dependent type.
5252 We generalize this to just say that the address of a member of a
5253 dependent class is value-dependent; the above doesn't cover the
5254 address of a static data member named with an unqualified-id. */
5257 has_value_dependent_address (tree op)
5259 /* We could use get_inner_reference here, but there's no need;
5260 this is only relevant for template non-type arguments, which
5261 can only be expressed as &id-expression. */
5264 tree ctx = CP_DECL_CONTEXT (op);
5265 if (TYPE_P (ctx) && dependent_type_p (ctx))
5272 /* Attempt to convert the non-type template parameter EXPR to the
5273 indicated TYPE. If the conversion is successful, return the
5274 converted value. If the conversion is unsuccessful, return
5275 NULL_TREE if we issued an error message, or error_mark_node if we
5276 did not. We issue error messages for out-and-out bad template
5277 parameters, but not simply because the conversion failed, since we
5278 might be just trying to do argument deduction. Both TYPE and EXPR
5279 must be non-dependent.
5281 The conversion follows the special rules described in
5282 [temp.arg.nontype], and it is much more strict than an implicit
5285 This function is called twice for each template argument (see
5286 lookup_template_class for a more accurate description of this
5287 problem). This means that we need to handle expressions which
5288 are not valid in a C++ source, but can be created from the
5289 first call (for instance, casts to perform conversions). These
5290 hacks can go away after we fix the double coercion problem. */
5293 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5297 /* Detect immediately string literals as invalid non-type argument.
5298 This special-case is not needed for correctness (we would easily
5299 catch this later), but only to provide better diagnostic for this
5300 common user mistake. As suggested by DR 100, we do not mention
5301 linkage issues in the diagnostic as this is not the point. */
5302 /* FIXME we're making this OK. */
5303 if (TREE_CODE (expr) == STRING_CST)
5305 if (complain & tf_error)
5306 error ("%qE is not a valid template argument for type %qT "
5307 "because string literals can never be used in this context",
5312 /* Add the ADDR_EXPR now for the benefit of
5313 value_dependent_expression_p. */
5314 if (TYPE_PTROBV_P (type))
5315 expr = decay_conversion (expr);
5317 /* If we are in a template, EXPR may be non-dependent, but still
5318 have a syntactic, rather than semantic, form. For example, EXPR
5319 might be a SCOPE_REF, rather than the VAR_DECL to which the
5320 SCOPE_REF refers. Preserving the qualifying scope is necessary
5321 so that access checking can be performed when the template is
5322 instantiated -- but here we need the resolved form so that we can
5323 convert the argument. */
5324 if (TYPE_REF_OBJ_P (type)
5325 && has_value_dependent_address (expr))
5326 /* If we want the address and it's value-dependent, don't fold. */;
5327 else if (!type_unknown_p (expr))
5328 expr = fold_non_dependent_expr_sfinae (expr, complain);
5329 if (error_operand_p (expr))
5330 return error_mark_node;
5331 expr_type = TREE_TYPE (expr);
5332 if (TREE_CODE (type) == REFERENCE_TYPE)
5333 expr = mark_lvalue_use (expr);
5335 expr = mark_rvalue_use (expr);
5337 /* HACK: Due to double coercion, we can get a
5338 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5339 which is the tree that we built on the first call (see
5340 below when coercing to reference to object or to reference to
5341 function). We just strip everything and get to the arg.
5342 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5344 if (TREE_CODE (expr) == NOP_EXPR)
5346 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5348 /* ??? Maybe we could use convert_from_reference here, but we
5349 would need to relax its constraints because the NOP_EXPR
5350 could actually change the type to something more cv-qualified,
5351 and this is not folded by convert_from_reference. */
5352 tree addr = TREE_OPERAND (expr, 0);
5353 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
5354 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5355 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5356 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5357 (TREE_TYPE (expr_type),
5358 TREE_TYPE (TREE_TYPE (addr))));
5360 expr = TREE_OPERAND (addr, 0);
5361 expr_type = TREE_TYPE (expr);
5364 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5365 parameter is a pointer to object, through decay and
5366 qualification conversion. Let's strip everything. */
5367 else if (TYPE_PTROBV_P (type))
5370 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5371 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5372 /* Skip the ADDR_EXPR only if it is part of the decay for
5373 an array. Otherwise, it is part of the original argument
5374 in the source code. */
5375 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5376 expr = TREE_OPERAND (expr, 0);
5377 expr_type = TREE_TYPE (expr);
5381 /* [temp.arg.nontype]/5, bullet 1
5383 For a non-type template-parameter of integral or enumeration type,
5384 integral promotions (_conv.prom_) and integral conversions
5385 (_conv.integral_) are applied. */
5386 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5388 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5389 t = maybe_constant_value (t);
5390 if (t != error_mark_node)
5393 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5394 return error_mark_node;
5396 /* Notice that there are constant expressions like '4 % 0' which
5397 do not fold into integer constants. */
5398 if (TREE_CODE (expr) != INTEGER_CST)
5400 if (complain & tf_error)
5402 error ("%qE is not a valid template argument for type %qT "
5403 "because it is a non-constant expression", expr, type);
5404 cxx_constant_value (expr);
5409 /* [temp.arg.nontype]/5, bullet 2
5411 For a non-type template-parameter of type pointer to object,
5412 qualification conversions (_conv.qual_) and the array-to-pointer
5413 conversion (_conv.array_) are applied. */
5414 else if (TYPE_PTROBV_P (type))
5416 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5418 A template-argument for a non-type, non-template template-parameter
5419 shall be one of: [...]
5421 -- the name of a non-type template-parameter;
5422 -- the address of an object or function with external linkage, [...]
5423 expressed as "& id-expression" where the & is optional if the name
5424 refers to a function or array, or if the corresponding
5425 template-parameter is a reference.
5427 Here, we do not care about functions, as they are invalid anyway
5428 for a parameter of type pointer-to-object. */
5430 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5431 /* Non-type template parameters are OK. */
5433 else if (TREE_CODE (expr) != ADDR_EXPR
5434 && TREE_CODE (expr_type) != ARRAY_TYPE)
5436 if (TREE_CODE (expr) == VAR_DECL)
5438 error ("%qD is not a valid template argument "
5439 "because %qD is a variable, not the address of "
5444 /* Other values, like integer constants, might be valid
5445 non-type arguments of some other type. */
5446 return error_mark_node;
5452 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5453 ? TREE_OPERAND (expr, 0) : expr);
5454 if (TREE_CODE (decl) != VAR_DECL)
5456 error ("%qE is not a valid template argument of type %qT "
5457 "because %qE is not a variable",
5461 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5463 error ("%qE is not a valid template argument of type %qT "
5464 "because %qD does not have external linkage",
5470 expr = decay_conversion (expr);
5471 if (expr == error_mark_node)
5472 return error_mark_node;
5474 expr = perform_qualification_conversions (type, expr);
5475 if (expr == error_mark_node)
5476 return error_mark_node;
5478 /* [temp.arg.nontype]/5, bullet 3
5480 For a non-type template-parameter of type reference to object, no
5481 conversions apply. The type referred to by the reference may be more
5482 cv-qualified than the (otherwise identical) type of the
5483 template-argument. The template-parameter is bound directly to the
5484 template-argument, which must be an lvalue. */
5485 else if (TYPE_REF_OBJ_P (type))
5487 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5489 return error_mark_node;
5491 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5493 error ("%qE is not a valid template argument for type %qT "
5494 "because of conflicts in cv-qualification", expr, type);
5498 if (!real_lvalue_p (expr))
5500 error ("%qE is not a valid template argument for type %qT "
5501 "because it is not an lvalue", expr, type);
5505 /* [temp.arg.nontype]/1
5507 A template-argument for a non-type, non-template template-parameter
5508 shall be one of: [...]
5510 -- the address of an object or function with external linkage. */
5511 if (TREE_CODE (expr) == INDIRECT_REF
5512 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5514 expr = TREE_OPERAND (expr, 0);
5517 error ("%q#D is not a valid template argument for type %qT "
5518 "because a reference variable does not have a constant "
5519 "address", expr, type);
5526 error ("%qE is not a valid template argument for type %qT "
5527 "because it is not an object with external linkage",
5532 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5534 error ("%qE is not a valid template argument for type %qT "
5535 "because object %qD has not external linkage",
5540 expr = build_nop (type, build_address (expr));
5542 /* [temp.arg.nontype]/5, bullet 4
5544 For a non-type template-parameter of type pointer to function, only
5545 the function-to-pointer conversion (_conv.func_) is applied. If the
5546 template-argument represents a set of overloaded functions (or a
5547 pointer to such), the matching function is selected from the set
5549 else if (TYPE_PTRFN_P (type))
5551 /* If the argument is a template-id, we might not have enough
5552 context information to decay the pointer. */
5553 if (!type_unknown_p (expr_type))
5555 expr = decay_conversion (expr);
5556 if (expr == error_mark_node)
5557 return error_mark_node;
5560 expr = convert_nontype_argument_function (type, expr);
5561 if (!expr || expr == error_mark_node)
5564 if (TREE_CODE (expr) != ADDR_EXPR)
5566 error ("%qE is not a valid template argument for type %qT", expr, type);
5567 error ("it must be the address of a function with external linkage");
5571 /* [temp.arg.nontype]/5, bullet 5
5573 For a non-type template-parameter of type reference to function, no
5574 conversions apply. If the template-argument represents a set of
5575 overloaded functions, the matching function is selected from the set
5577 else if (TYPE_REFFN_P (type))
5579 if (TREE_CODE (expr) == ADDR_EXPR)
5581 error ("%qE is not a valid template argument for type %qT "
5582 "because it is a pointer", expr, type);
5583 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5587 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5588 if (!expr || expr == error_mark_node)
5591 expr = build_nop (type, build_address (expr));
5593 /* [temp.arg.nontype]/5, bullet 6
5595 For a non-type template-parameter of type pointer to member function,
5596 no conversions apply. If the template-argument represents a set of
5597 overloaded member functions, the matching member function is selected
5598 from the set (_over.over_). */
5599 else if (TYPE_PTRMEMFUNC_P (type))
5601 expr = instantiate_type (type, expr, tf_none);
5602 if (expr == error_mark_node)
5603 return error_mark_node;
5605 /* [temp.arg.nontype] bullet 1 says the pointer to member
5606 expression must be a pointer-to-member constant. */
5607 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5608 return error_mark_node;
5610 /* There is no way to disable standard conversions in
5611 resolve_address_of_overloaded_function (called by
5612 instantiate_type). It is possible that the call succeeded by
5613 converting &B::I to &D::I (where B is a base of D), so we need
5614 to reject this conversion here.
5616 Actually, even if there was a way to disable standard conversions,
5617 it would still be better to reject them here so that we can
5618 provide a superior diagnostic. */
5619 if (!same_type_p (TREE_TYPE (expr), type))
5621 error ("%qE is not a valid template argument for type %qT "
5622 "because it is of type %qT", expr, type,
5624 /* If we are just one standard conversion off, explain. */
5625 if (can_convert (type, TREE_TYPE (expr)))
5626 inform (input_location,
5627 "standard conversions are not allowed in this context");
5631 /* [temp.arg.nontype]/5, bullet 7
5633 For a non-type template-parameter of type pointer to data member,
5634 qualification conversions (_conv.qual_) are applied. */
5635 else if (TYPE_PTRMEM_P (type))
5637 /* [temp.arg.nontype] bullet 1 says the pointer to member
5638 expression must be a pointer-to-member constant. */
5639 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5640 return error_mark_node;
5642 expr = perform_qualification_conversions (type, expr);
5643 if (expr == error_mark_node)
5646 /* A template non-type parameter must be one of the above. */
5650 /* Sanity check: did we actually convert the argument to the
5652 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5653 (type, TREE_TYPE (expr)));
5657 /* Subroutine of coerce_template_template_parms, which returns 1 if
5658 PARM_PARM and ARG_PARM match using the rule for the template
5659 parameters of template template parameters. Both PARM and ARG are
5660 template parameters; the rest of the arguments are the same as for
5661 coerce_template_template_parms.
5664 coerce_template_template_parm (tree parm,
5666 tsubst_flags_t complain,
5670 if (arg == NULL_TREE || arg == error_mark_node
5671 || parm == NULL_TREE || parm == error_mark_node)
5674 if (TREE_CODE (arg) != TREE_CODE (parm))
5677 switch (TREE_CODE (parm))
5680 /* We encounter instantiations of templates like
5681 template <template <template <class> class> class TT>
5684 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5685 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5687 if (!coerce_template_template_parms
5688 (parmparm, argparm, complain, in_decl, outer_args))
5694 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5695 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5696 /* Argument is a parameter pack but parameter is not. */
5701 /* The tsubst call is used to handle cases such as
5703 template <int> class C {};
5704 template <class T, template <T> class TT> class D {};
5707 i.e. the parameter list of TT depends on earlier parameters. */
5708 if (!uses_template_parms (TREE_TYPE (arg))
5710 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5714 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5715 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5716 /* Argument is a parameter pack but parameter is not. */
5729 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5730 template template parameters. Both PARM_PARMS and ARG_PARMS are
5731 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5734 Consider the example:
5735 template <class T> class A;
5736 template<template <class U> class TT> class B;
5738 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5739 the parameters to A, and OUTER_ARGS contains A. */
5742 coerce_template_template_parms (tree parm_parms,
5744 tsubst_flags_t complain,
5748 int nparms, nargs, i;
5752 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5753 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5755 nparms = TREE_VEC_LENGTH (parm_parms);
5756 nargs = TREE_VEC_LENGTH (arg_parms);
5758 /* Determine whether we have a parameter pack at the end of the
5759 template template parameter's template parameter list. */
5760 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5762 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5764 if (parm == error_mark_node)
5767 switch (TREE_CODE (parm))
5771 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5776 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5786 && !(variadic_p && nargs >= nparms - 1))
5789 /* Check all of the template parameters except the parameter pack at
5790 the end (if any). */
5791 for (i = 0; i < nparms - variadic_p; ++i)
5793 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5794 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5797 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5798 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5800 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5808 /* Check each of the template parameters in the template
5809 argument against the template parameter pack at the end of
5810 the template template parameter. */
5811 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5814 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5816 for (; i < nargs; ++i)
5818 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5821 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5823 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5832 /* Verifies that the deduced template arguments (in TARGS) for the
5833 template template parameters (in TPARMS) represent valid bindings,
5834 by comparing the template parameter list of each template argument
5835 to the template parameter list of its corresponding template
5836 template parameter, in accordance with DR150. This
5837 routine can only be called after all template arguments have been
5838 deduced. It will return TRUE if all of the template template
5839 parameter bindings are okay, FALSE otherwise. */
5841 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5843 int i, ntparms = TREE_VEC_LENGTH (tparms);
5846 /* We're dealing with template parms in this process. */
5847 ++processing_template_decl;
5849 targs = INNERMOST_TEMPLATE_ARGS (targs);
5851 for (i = 0; i < ntparms; ++i)
5853 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5854 tree targ = TREE_VEC_ELT (targs, i);
5856 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5858 tree packed_args = NULL_TREE;
5861 if (ARGUMENT_PACK_P (targ))
5863 /* Look inside the argument pack. */
5864 packed_args = ARGUMENT_PACK_ARGS (targ);
5865 len = TREE_VEC_LENGTH (packed_args);
5868 for (idx = 0; idx < len; ++idx)
5870 tree targ_parms = NULL_TREE;
5873 /* Extract the next argument from the argument
5875 targ = TREE_VEC_ELT (packed_args, idx);
5877 if (PACK_EXPANSION_P (targ))
5878 /* Look at the pattern of the pack expansion. */
5879 targ = PACK_EXPANSION_PATTERN (targ);
5881 /* Extract the template parameters from the template
5883 if (TREE_CODE (targ) == TEMPLATE_DECL)
5884 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5885 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5886 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5888 /* Verify that we can coerce the template template
5889 parameters from the template argument to the template
5890 parameter. This requires an exact match. */
5892 && !coerce_template_template_parms
5893 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5908 --processing_template_decl;
5912 /* Convert the indicated template ARG as necessary to match the
5913 indicated template PARM. Returns the converted ARG, or
5914 error_mark_node if the conversion was unsuccessful. Error and
5915 warning messages are issued under control of COMPLAIN. This
5916 conversion is for the Ith parameter in the parameter list. ARGS is
5917 the full set of template arguments deduced so far. */
5920 convert_template_argument (tree parm,
5923 tsubst_flags_t complain,
5929 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5931 if (TREE_CODE (arg) == TREE_LIST
5932 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5934 /* The template argument was the name of some
5935 member function. That's usually
5936 invalid, but static members are OK. In any
5937 case, grab the underlying fields/functions
5938 and issue an error later if required. */
5939 orig_arg = TREE_VALUE (arg);
5940 TREE_TYPE (arg) = unknown_type_node;
5945 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5946 requires_type = (TREE_CODE (parm) == TYPE_DECL
5947 || requires_tmpl_type);
5949 /* When determining whether an argument pack expansion is a template,
5950 look at the pattern. */
5951 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5952 arg = PACK_EXPANSION_PATTERN (arg);
5954 /* Deal with an injected-class-name used as a template template arg. */
5955 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5957 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5958 if (TREE_CODE (t) == TEMPLATE_DECL)
5960 if (complain & tf_warning_or_error)
5961 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5962 " used as template template argument", TYPE_NAME (arg));
5963 else if (flag_pedantic_errors)
5971 ((TREE_CODE (arg) == TEMPLATE_DECL
5972 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5973 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5974 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5977 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5978 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5979 arg = TYPE_STUB_DECL (arg);
5981 is_type = TYPE_P (arg) || is_tmpl_type;
5983 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5984 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5986 permerror (input_location, "to refer to a type member of a template parameter, "
5987 "use %<typename %E%>", orig_arg);
5989 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5990 TREE_OPERAND (arg, 1),
5992 complain & tf_error);
5996 if (is_type != requires_type)
6000 if (complain & tf_error)
6002 error ("type/value mismatch at argument %d in template "
6003 "parameter list for %qD",
6006 error (" expected a constant of type %qT, got %qT",
6008 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6009 else if (requires_tmpl_type)
6010 error (" expected a class template, got %qE", orig_arg);
6012 error (" expected a type, got %qE", orig_arg);
6015 return error_mark_node;
6017 if (is_tmpl_type ^ requires_tmpl_type)
6019 if (in_decl && (complain & tf_error))
6021 error ("type/value mismatch at argument %d in template "
6022 "parameter list for %qD",
6025 error (" expected a type, got %qT", DECL_NAME (arg));
6027 error (" expected a class template, got %qT", orig_arg);
6029 return error_mark_node;
6034 if (requires_tmpl_type)
6036 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6037 /* The number of argument required is not known yet.
6038 Just accept it for now. */
6039 val = TREE_TYPE (arg);
6042 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6045 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6047 if (coerce_template_template_parms (parmparm, argparm,
6053 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6055 if (val != error_mark_node)
6057 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6058 val = TREE_TYPE (val);
6059 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6060 val = make_pack_expansion (val);
6065 if (in_decl && (complain & tf_error))
6067 error ("type/value mismatch at argument %d in "
6068 "template parameter list for %qD",
6070 error (" expected a template of type %qD, got %qT",
6074 val = error_mark_node;
6080 /* We only form one instance of each template specialization.
6081 Therefore, if we use a non-canonical variant (i.e., a
6082 typedef), any future messages referring to the type will use
6083 the typedef, which is confusing if those future uses do not
6084 themselves also use the typedef. */
6086 val = strip_typedefs (val);
6090 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6092 if (invalid_nontype_parm_type_p (t, complain))
6093 return error_mark_node;
6095 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6097 if (same_type_p (t, TREE_TYPE (orig_arg)))
6101 /* Not sure if this is reachable, but it doesn't hurt
6103 error ("type mismatch in nontype parameter pack");
6104 val = error_mark_node;
6107 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6108 /* We used to call digest_init here. However, digest_init
6109 will report errors, which we don't want when complain
6110 is zero. More importantly, digest_init will try too
6111 hard to convert things: for example, `0' should not be
6112 converted to pointer type at this point according to
6113 the standard. Accepting this is not merely an
6114 extension, since deciding whether or not these
6115 conversions can occur is part of determining which
6116 function template to call, or whether a given explicit
6117 argument specification is valid. */
6118 val = convert_nontype_argument (t, orig_arg, complain);
6122 if (val == NULL_TREE)
6123 val = error_mark_node;
6124 else if (val == error_mark_node && (complain & tf_error))
6125 error ("could not convert template argument %qE to %qT", orig_arg, t);
6127 if (TREE_CODE (val) == SCOPE_REF)
6129 /* Strip typedefs from the SCOPE_REF. */
6130 tree type = strip_typedefs (TREE_TYPE (val));
6131 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
6132 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6133 QUALIFIED_NAME_IS_TEMPLATE (val));
6140 /* Coerces the remaining template arguments in INNER_ARGS (from
6141 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6142 Returns the coerced argument pack. PARM_IDX is the position of this
6143 parameter in the template parameter list. ARGS is the original
6144 template argument list. */
6146 coerce_template_parameter_pack (tree parms,
6154 tsubst_flags_t complain)
6156 tree parm = TREE_VEC_ELT (parms, parm_idx);
6157 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6160 tree packed_types = NULL_TREE;
6162 if (arg_idx > nargs)
6165 packed_args = make_tree_vec (nargs - arg_idx);
6167 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6168 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6170 /* When the template parameter is a non-type template
6171 parameter pack whose type uses parameter packs, we need
6172 to look at each of the template arguments
6173 separately. Build a vector of the types for these
6174 non-type template parameters in PACKED_TYPES. */
6176 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6177 packed_types = tsubst_pack_expansion (expansion, args,
6180 if (packed_types == error_mark_node)
6181 return error_mark_node;
6183 /* Check that we have the right number of arguments. */
6185 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6186 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6189 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6190 error ("wrong number of template arguments (%d, should be %d)",
6191 nargs, needed_parms);
6192 return error_mark_node;
6195 /* If we aren't able to check the actual arguments now
6196 (because they haven't been expanded yet), we can at least
6197 verify that all of the types used for the non-type
6198 template parameter pack are, in fact, valid for non-type
6199 template parameters. */
6201 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6203 int j, len = TREE_VEC_LENGTH (packed_types);
6204 for (j = 0; j < len; ++j)
6206 tree t = TREE_VEC_ELT (packed_types, j);
6207 if (invalid_nontype_parm_type_p (t, complain))
6208 return error_mark_node;
6213 /* Convert the remaining arguments, which will be a part of the
6214 parameter pack "parm". */
6215 for (; arg_idx < nargs; ++arg_idx)
6217 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6218 tree actual_parm = TREE_VALUE (parm);
6220 if (packed_types && !PACK_EXPANSION_P (arg))
6222 /* When we have a vector of types (corresponding to the
6223 non-type template parameter pack that uses parameter
6224 packs in its type, as mention above), and the
6225 argument is not an expansion (which expands to a
6226 currently unknown number of arguments), clone the
6227 parm and give it the next type in PACKED_TYPES. */
6228 actual_parm = copy_node (actual_parm);
6229 TREE_TYPE (actual_parm) =
6230 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6233 if (arg != error_mark_node)
6234 arg = convert_template_argument (actual_parm,
6235 arg, new_args, complain, parm_idx,
6237 if (arg == error_mark_node)
6239 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6242 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6243 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6244 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6247 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6248 TREE_TYPE (argument_pack)
6249 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6250 TREE_CONSTANT (argument_pack) = 1;
6253 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6254 #ifdef ENABLE_CHECKING
6255 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6256 TREE_VEC_LENGTH (packed_args));
6258 return argument_pack;
6261 /* Convert all template arguments to their appropriate types, and
6262 return a vector containing the innermost resulting template
6263 arguments. If any error occurs, return error_mark_node. Error and
6264 warning messages are issued under control of COMPLAIN.
6266 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6267 for arguments not specified in ARGS. Otherwise, if
6268 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6269 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6270 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6274 coerce_template_parms (tree parms,
6277 tsubst_flags_t complain,
6278 bool require_all_args,
6279 bool use_default_args)
6281 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6284 tree new_inner_args;
6285 int saved_unevaluated_operand;
6286 int saved_inhibit_evaluation_warnings;
6288 /* When used as a boolean value, indicates whether this is a
6289 variadic template parameter list. Since it's an int, we can also
6290 subtract it from nparms to get the number of non-variadic
6294 if (args == error_mark_node)
6295 return error_mark_node;
6297 nparms = TREE_VEC_LENGTH (parms);
6299 /* Determine if there are any parameter packs. */
6300 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6302 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6303 if (template_parameter_pack_p (tparm))
6307 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6308 /* If there are 0 or 1 parameter packs, we need to expand any argument
6309 packs so that we can deduce a parameter pack from some non-packed args
6310 followed by an argument pack, as in variadic85.C. If there are more
6311 than that, we need to leave argument packs intact so the arguments are
6312 assigned to the right parameter packs. This should only happen when
6313 dealing with a nested class inside a partial specialization of a class
6314 template, as in variadic92.C. */
6315 if (variadic_p <= 1)
6316 inner_args = expand_template_argument_pack (inner_args);
6318 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6319 if ((nargs > nparms && !variadic_p)
6320 || (nargs < nparms - variadic_p
6322 && (!use_default_args
6323 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6324 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6326 if (complain & tf_error)
6331 error ("wrong number of template arguments "
6332 "(%d, should be %d or more)", nargs, nparms);
6335 error ("wrong number of template arguments "
6336 "(%d, should be %d)", nargs, nparms);
6339 error ("provided for %q+D", in_decl);
6342 return error_mark_node;
6345 /* We need to evaluate the template arguments, even though this
6346 template-id may be nested within a "sizeof". */
6347 saved_unevaluated_operand = cp_unevaluated_operand;
6348 cp_unevaluated_operand = 0;
6349 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6350 c_inhibit_evaluation_warnings = 0;
6351 new_inner_args = make_tree_vec (nparms);
6352 new_args = add_outermost_template_args (args, new_inner_args);
6353 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6358 /* Get the Ith template parameter. */
6359 parm = TREE_VEC_ELT (parms, parm_idx);
6361 if (parm == error_mark_node)
6363 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6367 /* Calculate the next argument. */
6368 if (arg_idx < nargs)
6369 arg = TREE_VEC_ELT (inner_args, arg_idx);
6373 if (template_parameter_pack_p (TREE_VALUE (parm))
6374 && !(arg && ARGUMENT_PACK_P (arg)))
6376 /* All remaining arguments will be placed in the
6377 template parameter pack PARM. */
6378 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6379 inner_args, arg_idx,
6383 /* Store this argument. */
6384 if (arg == error_mark_node)
6386 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6388 /* We are done with all of the arguments. */
6395 if (PACK_EXPANSION_P (arg))
6397 if (complain & tf_error)
6399 /* FIXME this restriction was removed by N2555; see
6401 /* If ARG is a pack expansion, but PARM is not a
6402 template parameter pack (if it were, we would have
6403 handled it above), we're trying to expand into a
6404 fixed-length argument list. */
6405 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6406 sorry ("cannot expand %<%E%> into a fixed-length "
6407 "argument list", arg);
6409 sorry ("cannot expand %<%T%> into a fixed-length "
6410 "argument list", arg);
6412 return error_mark_node;
6415 else if (require_all_args)
6417 /* There must be a default arg in this case. */
6418 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6420 /* The position of the first default template argument,
6421 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6423 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6424 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6429 if (arg == error_mark_node)
6431 if (complain & tf_error)
6432 error ("template argument %d is invalid", arg_idx + 1);
6435 /* This only occurs if there was an error in the template
6436 parameter list itself (which we would already have
6437 reported) that we are trying to recover from, e.g., a class
6438 template with a parameter list such as
6439 template<typename..., typename>. */
6440 return error_mark_node;
6442 arg = convert_template_argument (TREE_VALUE (parm),
6443 arg, new_args, complain,
6446 if (arg == error_mark_node)
6448 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6450 cp_unevaluated_operand = saved_unevaluated_operand;
6451 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6454 return error_mark_node;
6456 #ifdef ENABLE_CHECKING
6457 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6458 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6459 TREE_VEC_LENGTH (new_inner_args));
6462 return new_inner_args;
6465 /* Returns 1 if template args OT and NT are equivalent. */
6468 template_args_equal (tree ot, tree nt)
6473 if (TREE_CODE (nt) == TREE_VEC)
6474 /* For member templates */
6475 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6476 else if (PACK_EXPANSION_P (ot))
6477 return PACK_EXPANSION_P (nt)
6478 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6479 PACK_EXPANSION_PATTERN (nt));
6480 else if (ARGUMENT_PACK_P (ot))
6485 if (!ARGUMENT_PACK_P (nt))
6488 opack = ARGUMENT_PACK_ARGS (ot);
6489 npack = ARGUMENT_PACK_ARGS (nt);
6490 len = TREE_VEC_LENGTH (opack);
6491 if (TREE_VEC_LENGTH (npack) != len)
6493 for (i = 0; i < len; ++i)
6494 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6495 TREE_VEC_ELT (npack, i)))
6499 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6501 /* We get here probably because we are in the middle of substituting
6502 into the pattern of a pack expansion. In that case the
6503 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6504 interested in. So we want to use the initial pack argument for
6506 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6507 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6508 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6509 return template_args_equal (ot, nt);
6511 else if (TYPE_P (nt))
6512 return TYPE_P (ot) && same_type_p (ot, nt);
6513 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6516 return cp_tree_equal (ot, nt);
6519 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6520 of template arguments. Returns 0 otherwise. */
6523 comp_template_args (tree oldargs, tree newargs)
6527 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6530 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6532 tree nt = TREE_VEC_ELT (newargs, i);
6533 tree ot = TREE_VEC_ELT (oldargs, i);
6535 if (! template_args_equal (ot, nt))
6542 add_pending_template (tree d)
6544 tree ti = (TYPE_P (d)
6545 ? CLASSTYPE_TEMPLATE_INFO (d)
6546 : DECL_TEMPLATE_INFO (d));
6547 struct pending_template *pt;
6550 if (TI_PENDING_TEMPLATE_FLAG (ti))
6553 /* We are called both from instantiate_decl, where we've already had a
6554 tinst_level pushed, and instantiate_template, where we haven't.
6556 level = !current_tinst_level || current_tinst_level->decl != d;
6559 push_tinst_level (d);
6561 pt = ggc_alloc_pending_template ();
6563 pt->tinst = current_tinst_level;
6564 if (last_pending_template)
6565 last_pending_template->next = pt;
6567 pending_templates = pt;
6569 last_pending_template = pt;
6571 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6578 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6579 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6580 documentation for TEMPLATE_ID_EXPR. */
6583 lookup_template_function (tree fns, tree arglist)
6587 if (fns == error_mark_node || arglist == error_mark_node)
6588 return error_mark_node;
6590 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6591 gcc_assert (fns && (is_overloaded_fn (fns)
6592 || TREE_CODE (fns) == IDENTIFIER_NODE));
6594 if (BASELINK_P (fns))
6596 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6598 BASELINK_FUNCTIONS (fns),
6603 type = TREE_TYPE (fns);
6604 if (TREE_CODE (fns) == OVERLOAD || !type)
6605 type = unknown_type_node;
6607 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6610 /* Within the scope of a template class S<T>, the name S gets bound
6611 (in build_self_reference) to a TYPE_DECL for the class, not a
6612 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6613 or one of its enclosing classes, and that type is a template,
6614 return the associated TEMPLATE_DECL. Otherwise, the original
6617 Also handle the case when DECL is a TREE_LIST of ambiguous
6618 injected-class-names from different bases. */
6621 maybe_get_template_decl_from_type_decl (tree decl)
6623 if (decl == NULL_TREE)
6626 /* DR 176: A lookup that finds an injected-class-name (10.2
6627 [class.member.lookup]) can result in an ambiguity in certain cases
6628 (for example, if it is found in more than one base class). If all of
6629 the injected-class-names that are found refer to specializations of
6630 the same class template, and if the name is followed by a
6631 template-argument-list, the reference refers to the class template
6632 itself and not a specialization thereof, and is not ambiguous. */
6633 if (TREE_CODE (decl) == TREE_LIST)
6635 tree t, tmpl = NULL_TREE;
6636 for (t = decl; t; t = TREE_CHAIN (t))
6638 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6641 else if (tmpl != elt)
6644 if (tmpl && t == NULL_TREE)
6650 return (decl != NULL_TREE
6651 && DECL_SELF_REFERENCE_P (decl)
6652 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6653 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6656 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6657 parameters, find the desired type.
6659 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6661 IN_DECL, if non-NULL, is the template declaration we are trying to
6664 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6665 the class we are looking up.
6667 Issue error and warning messages under control of COMPLAIN.
6669 If the template class is really a local class in a template
6670 function, then the FUNCTION_CONTEXT is the function in which it is
6673 ??? Note that this function is currently called *twice* for each
6674 template-id: the first time from the parser, while creating the
6675 incomplete type (finish_template_type), and the second type during the
6676 real instantiation (instantiate_template_class). This is surely something
6677 that we want to avoid. It also causes some problems with argument
6678 coercion (see convert_nontype_argument for more information on this). */
6681 lookup_template_class (tree d1,
6686 tsubst_flags_t complain)
6688 tree templ = NULL_TREE, parmlist;
6695 timevar_push (TV_NAME_LOOKUP);
6697 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6699 tree value = innermost_non_namespace_value (d1);
6700 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6705 push_decl_namespace (context);
6706 templ = lookup_name (d1);
6707 templ = maybe_get_template_decl_from_type_decl (templ);
6709 pop_decl_namespace ();
6712 context = DECL_CONTEXT (templ);
6714 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6716 tree type = TREE_TYPE (d1);
6718 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6719 an implicit typename for the second A. Deal with it. */
6720 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6721 type = TREE_TYPE (type);
6723 if (CLASSTYPE_TEMPLATE_INFO (type))
6725 templ = CLASSTYPE_TI_TEMPLATE (type);
6726 d1 = DECL_NAME (templ);
6729 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6730 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6732 templ = TYPE_TI_TEMPLATE (d1);
6733 d1 = DECL_NAME (templ);
6735 else if (TREE_CODE (d1) == TEMPLATE_DECL
6736 && DECL_TEMPLATE_RESULT (d1)
6737 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6740 d1 = DECL_NAME (templ);
6741 context = DECL_CONTEXT (templ);
6744 /* Issue an error message if we didn't find a template. */
6747 if (complain & tf_error)
6748 error ("%qT is not a template", d1);
6749 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6752 if (TREE_CODE (templ) != TEMPLATE_DECL
6753 /* Make sure it's a user visible template, if it was named by
6755 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6756 && !PRIMARY_TEMPLATE_P (templ)))
6758 if (complain & tf_error)
6760 error ("non-template type %qT used as a template", d1);
6762 error ("for template declaration %q+D", in_decl);
6764 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6767 complain &= ~tf_user;
6769 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6771 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6772 template arguments */
6778 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6780 /* Consider an example where a template template parameter declared as
6782 template <class T, class U = std::allocator<T> > class TT
6784 The template parameter level of T and U are one level larger than
6785 of TT. To proper process the default argument of U, say when an
6786 instantiation `TT<int>' is seen, we need to build the full
6787 arguments containing {int} as the innermost level. Outer levels,
6788 available when not appearing as default template argument, can be
6789 obtained from the arguments of the enclosing template.
6791 Suppose that TT is later substituted with std::vector. The above
6792 instantiation is `TT<int, std::allocator<T> >' with TT at
6793 level 1, and T at level 2, while the template arguments at level 1
6794 becomes {std::vector} and the inner level 2 is {int}. */
6796 outer = DECL_CONTEXT (templ);
6798 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6799 else if (current_template_parms)
6800 /* This is an argument of the current template, so we haven't set
6801 DECL_CONTEXT yet. */
6802 outer = current_template_args ();
6805 arglist = add_to_template_args (outer, arglist);
6807 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6809 /*require_all_args=*/true,
6810 /*use_default_args=*/true);
6811 if (arglist2 == error_mark_node
6812 || (!uses_template_parms (arglist2)
6813 && check_instantiated_args (templ, arglist2, complain)))
6814 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6816 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6817 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6821 tree template_type = TREE_TYPE (templ);
6824 tree found = NULL_TREE;
6827 int is_dependent_type;
6828 int use_partial_inst_tmpl = false;
6830 gen_tmpl = most_general_template (templ);
6831 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6832 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6833 arg_depth = TMPL_ARGS_DEPTH (arglist);
6835 if (arg_depth == 1 && parm_depth > 1)
6837 /* We've been given an incomplete set of template arguments.
6840 template <class T> struct S1 {
6841 template <class U> struct S2 {};
6842 template <class U> struct S2<U*> {};
6845 we will be called with an ARGLIST of `U*', but the
6846 TEMPLATE will be `template <class T> template
6847 <class U> struct S1<T>::S2'. We must fill in the missing
6850 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6852 arg_depth = TMPL_ARGS_DEPTH (arglist);
6855 /* Now we should have enough arguments. */
6856 gcc_assert (parm_depth == arg_depth);
6858 /* From here on, we're only interested in the most general
6861 /* Calculate the BOUND_ARGS. These will be the args that are
6862 actually tsubst'd into the definition to create the
6866 /* We have multiple levels of arguments to coerce, at once. */
6868 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6870 tree bound_args = make_tree_vec (parm_depth);
6872 for (i = saved_depth,
6873 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6874 i > 0 && t != NULL_TREE;
6875 --i, t = TREE_CHAIN (t))
6878 if (i == saved_depth)
6879 a = coerce_template_parms (TREE_VALUE (t),
6882 /*require_all_args=*/true,
6883 /*use_default_args=*/true);
6885 /* Outer levels should have already been coerced. */
6886 a = TMPL_ARGS_LEVEL (arglist, i);
6888 /* Don't process further if one of the levels fails. */
6889 if (a == error_mark_node)
6891 /* Restore the ARGLIST to its full size. */
6892 TREE_VEC_LENGTH (arglist) = saved_depth;
6893 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6896 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6898 /* We temporarily reduce the length of the ARGLIST so
6899 that coerce_template_parms will see only the arguments
6900 corresponding to the template parameters it is
6902 TREE_VEC_LENGTH (arglist)--;
6905 /* Restore the ARGLIST to its full size. */
6906 TREE_VEC_LENGTH (arglist) = saved_depth;
6908 arglist = bound_args;
6912 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6913 INNERMOST_TEMPLATE_ARGS (arglist),
6916 /*require_all_args=*/true,
6917 /*use_default_args=*/true);
6919 if (arglist == error_mark_node)
6920 /* We were unable to bind the arguments. */
6921 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6923 /* In the scope of a template class, explicit references to the
6924 template class refer to the type of the template, not any
6925 instantiation of it. For example, in:
6927 template <class T> class C { void f(C<T>); }
6929 the `C<T>' is just the same as `C'. Outside of the
6930 class, however, such a reference is an instantiation. */
6932 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6933 || currently_open_class (template_type))
6934 /* comp_template_args is expensive, check it last. */
6935 && comp_template_args (TYPE_TI_ARGS (template_type),
6937 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6939 /* If we already have this specialization, return it. */
6940 elt.tmpl = gen_tmpl;
6942 hash = hash_specialization (&elt);
6943 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6947 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6949 is_dependent_type = uses_template_parms (arglist);
6951 /* If the deduced arguments are invalid, then the binding
6953 if (!is_dependent_type
6954 && check_instantiated_args (gen_tmpl,
6955 INNERMOST_TEMPLATE_ARGS (arglist),
6957 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6959 if (!is_dependent_type
6960 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6961 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6962 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6964 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6965 DECL_NAME (gen_tmpl),
6966 /*tag_scope=*/ts_global);
6967 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6970 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6973 context = global_namespace;
6975 /* Create the type. */
6976 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6978 if (!is_dependent_type)
6980 set_current_access_from_decl (TYPE_NAME (template_type));
6981 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
6982 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6983 arglist, complain, in_decl),
6984 SCOPED_ENUM_P (template_type), NULL);
6988 /* We don't want to call start_enum for this type, since
6989 the values for the enumeration constants may involve
6990 template parameters. And, no one should be interested
6991 in the enumeration constants for such a type. */
6992 t = cxx_make_type (ENUMERAL_TYPE);
6993 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6995 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
6999 t = make_class_type (TREE_CODE (template_type));
7000 CLASSTYPE_DECLARED_CLASS (t)
7001 = CLASSTYPE_DECLARED_CLASS (template_type);
7002 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7003 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7005 /* A local class. Make sure the decl gets registered properly. */
7006 if (context == current_function_decl)
7007 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7009 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7010 /* This instantiation is another name for the primary
7011 template type. Set the TYPE_CANONICAL field
7013 TYPE_CANONICAL (t) = template_type;
7014 else if (any_template_arguments_need_structural_equality_p (arglist))
7015 /* Some of the template arguments require structural
7016 equality testing, so this template class requires
7017 structural equality testing. */
7018 SET_TYPE_STRUCTURAL_EQUALITY (t);
7021 /* If we called start_enum or pushtag above, this information
7022 will already be set up. */
7025 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7027 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7028 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7029 DECL_SOURCE_LOCATION (type_decl)
7030 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7033 type_decl = TYPE_NAME (t);
7035 TREE_PRIVATE (type_decl)
7036 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7037 TREE_PROTECTED (type_decl)
7038 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7039 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7041 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7042 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7045 /* Let's consider the explicit specialization of a member
7046 of a class template specialization that is implicitely instantiated,
7051 template<class U> struct M {}; //#0
7056 struct S<int>::M<char> //#1
7060 [temp.expl.spec]/4 says this is valid.
7062 In this case, when we write:
7065 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7068 When we encounter #1, we want to store the partial instantiation
7069 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7071 For all cases other than this "explicit specialization of member of a
7072 class template", we just want to store the most general template into
7073 the CLASSTYPE_TI_TEMPLATE of M.
7075 This case of "explicit specialization of member of a class template"
7077 1/ the enclosing class is an instantiation of, and therefore not
7078 the same as, the context of the most general template, and
7079 2/ we aren't looking at the partial instantiation itself, i.e.
7080 the innermost arguments are not the same as the innermost parms of
7081 the most general template.
7083 So it's only when 1/ and 2/ happens that we want to use the partial
7084 instantiation of the member template in lieu of its most general
7087 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7088 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7089 /* the enclosing class must be an instantiation... */
7090 && CLASS_TYPE_P (context)
7091 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7093 tree partial_inst_args;
7094 TREE_VEC_LENGTH (arglist)--;
7095 ++processing_template_decl;
7097 tsubst (INNERMOST_TEMPLATE_ARGS
7098 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7099 arglist, complain, NULL_TREE);
7100 --processing_template_decl;
7101 TREE_VEC_LENGTH (arglist)++;
7102 use_partial_inst_tmpl =
7103 /*...and we must not be looking at the partial instantiation
7105 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7109 if (!use_partial_inst_tmpl)
7110 /* This case is easy; there are no member templates involved. */
7114 /* This is a full instantiation of a member template. Find
7115 the partial instantiation of which this is an instance. */
7117 /* Temporarily reduce by one the number of levels in the ARGLIST
7118 so as to avoid comparing the last set of arguments. */
7119 TREE_VEC_LENGTH (arglist)--;
7120 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7121 TREE_VEC_LENGTH (arglist)++;
7122 found = CLASSTYPE_TI_TEMPLATE (found);
7125 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7128 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
7129 &elt, hash, INSERT);
7130 *slot = ggc_alloc_spec_entry ();
7133 /* Note this use of the partial instantiation so we can check it
7134 later in maybe_process_partial_specialization. */
7135 DECL_TEMPLATE_INSTANTIATIONS (templ)
7136 = tree_cons (arglist, t,
7137 DECL_TEMPLATE_INSTANTIATIONS (templ));
7139 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7140 /* Now that the type has been registered on the instantiations
7141 list, we set up the enumerators. Because the enumeration
7142 constants may involve the enumeration type itself, we make
7143 sure to register the type first, and then create the
7144 constants. That way, doing tsubst_expr for the enumeration
7145 constants won't result in recursive calls here; we'll find
7146 the instantiation and exit above. */
7147 tsubst_enum (template_type, t, arglist);
7149 if (is_dependent_type)
7150 /* If the type makes use of template parameters, the
7151 code that generates debugging information will crash. */
7152 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7154 /* Possibly limit visibility based on template args. */
7155 TREE_PUBLIC (type_decl) = 1;
7156 determine_visibility (type_decl);
7158 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
7160 timevar_pop (TV_NAME_LOOKUP);
7167 /* True when we should also visit template parameters that occur in
7168 non-deduced contexts. */
7169 bool include_nondeduced_p;
7170 struct pointer_set_t *visited;
7173 /* Called from for_each_template_parm via walk_tree. */
7176 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7179 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7180 tree_fn_t fn = pfd->fn;
7181 void *data = pfd->data;
7184 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7185 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7186 pfd->include_nondeduced_p))
7187 return error_mark_node;
7189 switch (TREE_CODE (t))
7192 if (TYPE_PTRMEMFUNC_P (t))
7198 if (!TYPE_TEMPLATE_INFO (t))
7200 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7201 fn, data, pfd->visited,
7202 pfd->include_nondeduced_p))
7203 return error_mark_node;
7207 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7208 fn, data, pfd->visited,
7209 pfd->include_nondeduced_p)
7210 || for_each_template_parm (TYPE_MAX_VALUE (t),
7211 fn, data, pfd->visited,
7212 pfd->include_nondeduced_p))
7213 return error_mark_node;
7217 /* Since we're not going to walk subtrees, we have to do this
7219 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7220 pfd->visited, pfd->include_nondeduced_p))
7221 return error_mark_node;
7225 /* Check the return type. */
7226 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7227 pfd->include_nondeduced_p))
7228 return error_mark_node;
7230 /* Check the parameter types. Since default arguments are not
7231 instantiated until they are needed, the TYPE_ARG_TYPES may
7232 contain expressions that involve template parameters. But,
7233 no-one should be looking at them yet. And, once they're
7234 instantiated, they don't contain template parameters, so
7235 there's no point in looking at them then, either. */
7239 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7240 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7241 pfd->visited, pfd->include_nondeduced_p))
7242 return error_mark_node;
7244 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7245 want walk_tree walking into them itself. */
7251 if (pfd->include_nondeduced_p
7252 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7254 pfd->include_nondeduced_p))
7255 return error_mark_node;
7260 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7261 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7262 pfd->visited, pfd->include_nondeduced_p))
7263 return error_mark_node;
7268 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7269 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7270 pfd->visited, pfd->include_nondeduced_p))
7271 return error_mark_node;
7272 if (DECL_CONTEXT (t)
7273 && pfd->include_nondeduced_p
7274 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7275 pfd->visited, pfd->include_nondeduced_p))
7276 return error_mark_node;
7279 case BOUND_TEMPLATE_TEMPLATE_PARM:
7280 /* Record template parameters such as `T' inside `TT<T>'. */
7281 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7282 pfd->include_nondeduced_p))
7283 return error_mark_node;
7286 case TEMPLATE_TEMPLATE_PARM:
7287 case TEMPLATE_TYPE_PARM:
7288 case TEMPLATE_PARM_INDEX:
7289 if (fn && (*fn)(t, data))
7290 return error_mark_node;
7292 return error_mark_node;
7296 /* A template template parameter is encountered. */
7297 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7298 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7299 pfd->include_nondeduced_p))
7300 return error_mark_node;
7302 /* Already substituted template template parameter */
7308 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7310 pfd->include_nondeduced_p))
7311 return error_mark_node;
7315 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7316 && pfd->include_nondeduced_p
7317 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7318 (TREE_TYPE (t)), fn, data,
7319 pfd->visited, pfd->include_nondeduced_p))
7320 return error_mark_node;
7325 /* If there's no type, then this thing must be some expression
7326 involving template parameters. */
7327 if (!fn && !TREE_TYPE (t))
7328 return error_mark_node;
7333 case REINTERPRET_CAST_EXPR:
7334 case CONST_CAST_EXPR:
7335 case STATIC_CAST_EXPR:
7336 case DYNAMIC_CAST_EXPR:
7340 case PSEUDO_DTOR_EXPR:
7342 return error_mark_node;
7349 /* We didn't find any template parameters we liked. */
7353 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7354 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7355 call FN with the parameter and the DATA.
7356 If FN returns nonzero, the iteration is terminated, and
7357 for_each_template_parm returns 1. Otherwise, the iteration
7358 continues. If FN never returns a nonzero value, the value
7359 returned by for_each_template_parm is 0. If FN is NULL, it is
7360 considered to be the function which always returns 1.
7362 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7363 parameters that occur in non-deduced contexts. When false, only
7364 visits those template parameters that can be deduced. */
7367 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7368 struct pointer_set_t *visited,
7369 bool include_nondeduced_p)
7371 struct pair_fn_data pfd;
7377 pfd.include_nondeduced_p = include_nondeduced_p;
7379 /* Walk the tree. (Conceptually, we would like to walk without
7380 duplicates, but for_each_template_parm_r recursively calls
7381 for_each_template_parm, so we would need to reorganize a fair
7382 bit to use walk_tree_without_duplicates, so we keep our own
7385 pfd.visited = visited;
7387 pfd.visited = pointer_set_create ();
7388 result = cp_walk_tree (&t,
7389 for_each_template_parm_r,
7391 pfd.visited) != NULL_TREE;
7396 pointer_set_destroy (pfd.visited);
7403 /* Returns true if T depends on any template parameter. */
7406 uses_template_parms (tree t)
7409 int saved_processing_template_decl;
7411 saved_processing_template_decl = processing_template_decl;
7412 if (!saved_processing_template_decl)
7413 processing_template_decl = 1;
7415 dependent_p = dependent_type_p (t);
7416 else if (TREE_CODE (t) == TREE_VEC)
7417 dependent_p = any_dependent_template_arguments_p (t);
7418 else if (TREE_CODE (t) == TREE_LIST)
7419 dependent_p = (uses_template_parms (TREE_VALUE (t))
7420 || uses_template_parms (TREE_CHAIN (t)));
7421 else if (TREE_CODE (t) == TYPE_DECL)
7422 dependent_p = dependent_type_p (TREE_TYPE (t));
7425 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7426 || TREE_CODE (t) == OVERLOAD
7427 || TREE_CODE (t) == BASELINK
7428 || TREE_CODE (t) == IDENTIFIER_NODE
7429 || TREE_CODE (t) == TRAIT_EXPR
7430 || TREE_CODE (t) == CONSTRUCTOR
7431 || CONSTANT_CLASS_P (t))
7432 dependent_p = (type_dependent_expression_p (t)
7433 || value_dependent_expression_p (t));
7436 gcc_assert (t == error_mark_node);
7437 dependent_p = false;
7440 processing_template_decl = saved_processing_template_decl;
7445 /* Returns true if T depends on any template parameter with level LEVEL. */
7448 uses_template_parms_level (tree t, int level)
7450 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7451 /*include_nondeduced_p=*/true);
7454 static int tinst_depth;
7455 extern int max_tinst_depth;
7456 #ifdef GATHER_STATISTICS
7459 static int tinst_level_tick;
7460 static int last_template_error_tick;
7462 /* We're starting to instantiate D; record the template instantiation context
7463 for diagnostics and to restore it later. */
7466 push_tinst_level (tree d)
7468 struct tinst_level *new_level;
7470 if (tinst_depth >= max_tinst_depth)
7472 /* If the instantiation in question still has unbound template parms,
7473 we don't really care if we can't instantiate it, so just return.
7474 This happens with base instantiation for implicit `typename'. */
7475 if (uses_template_parms (d))
7478 last_template_error_tick = tinst_level_tick;
7479 error ("template instantiation depth exceeds maximum of %d (use "
7480 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7481 max_tinst_depth, d);
7483 print_instantiation_context ();
7488 new_level = ggc_alloc_tinst_level ();
7489 new_level->decl = d;
7490 new_level->locus = input_location;
7491 new_level->in_system_header_p = in_system_header;
7492 new_level->next = current_tinst_level;
7493 current_tinst_level = new_level;
7496 #ifdef GATHER_STATISTICS
7497 if (tinst_depth > depth_reached)
7498 depth_reached = tinst_depth;
7505 /* We're done instantiating this template; return to the instantiation
7509 pop_tinst_level (void)
7511 /* Restore the filename and line number stashed away when we started
7512 this instantiation. */
7513 input_location = current_tinst_level->locus;
7514 current_tinst_level = current_tinst_level->next;
7519 /* We're instantiating a deferred template; restore the template
7520 instantiation context in which the instantiation was requested, which
7521 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7524 reopen_tinst_level (struct tinst_level *level)
7526 struct tinst_level *t;
7529 for (t = level; t; t = t->next)
7532 current_tinst_level = level;
7537 /* Returns the TINST_LEVEL which gives the original instantiation
7540 struct tinst_level *
7541 outermost_tinst_level (void)
7543 struct tinst_level *level = current_tinst_level;
7546 level = level->next;
7550 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7553 parameter_of_template_p (tree parm, tree templ)
7558 if (!parm || !templ)
7561 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7562 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7564 parms = DECL_TEMPLATE_PARMS (templ);
7565 parms = INNERMOST_TEMPLATE_PARMS (parms);
7567 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7568 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7574 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7575 vector of template arguments, as for tsubst.
7577 Returns an appropriate tsubst'd friend declaration. */
7580 tsubst_friend_function (tree decl, tree args)
7584 if (TREE_CODE (decl) == FUNCTION_DECL
7585 && DECL_TEMPLATE_INSTANTIATION (decl)
7586 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7587 /* This was a friend declared with an explicit template
7588 argument list, e.g.:
7592 to indicate that f was a template instantiation, not a new
7593 function declaration. Now, we have to figure out what
7594 instantiation of what template. */
7596 tree template_id, arglist, fns;
7599 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7601 /* Friend functions are looked up in the containing namespace scope.
7602 We must enter that scope, to avoid finding member functions of the
7603 current class with same name. */
7604 push_nested_namespace (ns);
7605 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7606 tf_warning_or_error, NULL_TREE,
7607 /*integral_constant_expression_p=*/false);
7608 pop_nested_namespace (ns);
7609 arglist = tsubst (DECL_TI_ARGS (decl), args,
7610 tf_warning_or_error, NULL_TREE);
7611 template_id = lookup_template_function (fns, arglist);
7613 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7614 tmpl = determine_specialization (template_id, new_friend,
7616 /*need_member_template=*/0,
7617 TREE_VEC_LENGTH (args),
7619 return instantiate_template (tmpl, new_args, tf_error);
7622 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7624 /* The NEW_FRIEND will look like an instantiation, to the
7625 compiler, but is not an instantiation from the point of view of
7626 the language. For example, we might have had:
7628 template <class T> struct S {
7629 template <class U> friend void f(T, U);
7632 Then, in S<int>, template <class U> void f(int, U) is not an
7633 instantiation of anything. */
7634 if (new_friend == error_mark_node)
7635 return error_mark_node;
7637 DECL_USE_TEMPLATE (new_friend) = 0;
7638 if (TREE_CODE (decl) == TEMPLATE_DECL)
7640 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7641 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7642 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7645 /* The mangled name for the NEW_FRIEND is incorrect. The function
7646 is not a template instantiation and should not be mangled like
7647 one. Therefore, we forget the mangling here; we'll recompute it
7648 later if we need it. */
7649 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7651 SET_DECL_RTL (new_friend, NULL);
7652 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7655 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7658 tree new_friend_template_info;
7659 tree new_friend_result_template_info;
7661 int new_friend_is_defn;
7663 /* We must save some information from NEW_FRIEND before calling
7664 duplicate decls since that function will free NEW_FRIEND if
7666 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7667 new_friend_is_defn =
7668 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7669 (template_for_substitution (new_friend)))
7671 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7673 /* This declaration is a `primary' template. */
7674 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7676 new_friend_result_template_info
7677 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7680 new_friend_result_template_info = NULL_TREE;
7682 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7683 if (new_friend_is_defn)
7684 DECL_INITIAL (new_friend) = error_mark_node;
7686 /* Inside pushdecl_namespace_level, we will push into the
7687 current namespace. However, the friend function should go
7688 into the namespace of the template. */
7689 ns = decl_namespace_context (new_friend);
7690 push_nested_namespace (ns);
7691 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7692 pop_nested_namespace (ns);
7694 if (old_decl == error_mark_node)
7695 return error_mark_node;
7697 if (old_decl != new_friend)
7699 /* This new friend declaration matched an existing
7700 declaration. For example, given:
7702 template <class T> void f(T);
7703 template <class U> class C {
7704 template <class T> friend void f(T) {}
7707 the friend declaration actually provides the definition
7708 of `f', once C has been instantiated for some type. So,
7709 old_decl will be the out-of-class template declaration,
7710 while new_friend is the in-class definition.
7712 But, if `f' was called before this point, the
7713 instantiation of `f' will have DECL_TI_ARGS corresponding
7714 to `T' but not to `U', references to which might appear
7715 in the definition of `f'. Previously, the most general
7716 template for an instantiation of `f' was the out-of-class
7717 version; now it is the in-class version. Therefore, we
7718 run through all specialization of `f', adding to their
7719 DECL_TI_ARGS appropriately. In particular, they need a
7720 new set of outer arguments, corresponding to the
7721 arguments for this class instantiation.
7723 The same situation can arise with something like this:
7726 template <class T> class C {
7730 when `C<int>' is instantiated. Now, `f(int)' is defined
7733 if (!new_friend_is_defn)
7734 /* On the other hand, if the in-class declaration does
7735 *not* provide a definition, then we don't want to alter
7736 existing definitions. We can just leave everything
7741 tree new_template = TI_TEMPLATE (new_friend_template_info);
7742 tree new_args = TI_ARGS (new_friend_template_info);
7744 /* Overwrite whatever template info was there before, if
7745 any, with the new template information pertaining to
7747 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7749 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7751 /* We should have called reregister_specialization in
7753 gcc_assert (retrieve_specialization (new_template,
7757 /* Instantiate it if the global has already been used. */
7758 if (DECL_ODR_USED (old_decl))
7759 instantiate_decl (old_decl, /*defer_ok=*/true,
7760 /*expl_inst_class_mem_p=*/false);
7766 /* Indicate that the old function template is a partial
7768 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7769 = new_friend_result_template_info;
7771 gcc_assert (new_template
7772 == most_general_template (new_template));
7773 gcc_assert (new_template != old_decl);
7775 /* Reassign any specializations already in the hash table
7776 to the new more general template, and add the
7777 additional template args. */
7778 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7782 tree spec = TREE_VALUE (t);
7785 elt.tmpl = old_decl;
7786 elt.args = DECL_TI_ARGS (spec);
7787 elt.spec = NULL_TREE;
7789 htab_remove_elt (decl_specializations, &elt);
7792 = add_outermost_template_args (new_args,
7793 DECL_TI_ARGS (spec));
7795 register_specialization
7796 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7799 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7803 /* The information from NEW_FRIEND has been merged into OLD_DECL
7804 by duplicate_decls. */
7805 new_friend = old_decl;
7810 tree context = DECL_CONTEXT (new_friend);
7814 template <class T> class C {
7815 template <class U> friend void C1<U>::f (); // case 1
7816 friend void C2<T>::f (); // case 2
7818 we only need to make sure CONTEXT is a complete type for
7819 case 2. To distinguish between the two cases, we note that
7820 CONTEXT of case 1 remains dependent type after tsubst while
7821 this isn't true for case 2. */
7822 ++processing_template_decl;
7823 dependent_p = dependent_type_p (context);
7824 --processing_template_decl;
7827 && !complete_type_or_else (context, NULL_TREE))
7828 return error_mark_node;
7830 if (COMPLETE_TYPE_P (context))
7832 /* Check to see that the declaration is really present, and,
7833 possibly obtain an improved declaration. */
7834 tree fn = check_classfn (context,
7835 new_friend, NULL_TREE);
7845 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7846 template arguments, as for tsubst.
7848 Returns an appropriate tsubst'd friend type or error_mark_node on
7852 tsubst_friend_class (tree friend_tmpl, tree args)
7858 context = CP_DECL_CONTEXT (friend_tmpl);
7860 if (context != global_namespace)
7862 if (TREE_CODE (context) == NAMESPACE_DECL)
7863 push_nested_namespace (context);
7865 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7868 /* Look for a class template declaration. We look for hidden names
7869 because two friend declarations of the same template are the
7870 same. For example, in:
7873 template <typename> friend class F;
7875 template <typename> struct B {
7876 template <typename> friend class F;
7879 both F templates are the same. */
7880 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7881 /*block_p=*/true, 0,
7882 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7884 /* But, if we don't find one, it might be because we're in a
7885 situation like this:
7893 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7894 for `S<int>', not the TEMPLATE_DECL. */
7895 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7897 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7898 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7901 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7903 /* The friend template has already been declared. Just
7904 check to see that the declarations match, and install any new
7905 default parameters. We must tsubst the default parameters,
7906 of course. We only need the innermost template parameters
7907 because that is all that redeclare_class_template will look
7909 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7910 > TMPL_ARGS_DEPTH (args))
7913 location_t saved_input_location;
7914 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7915 args, tf_warning_or_error);
7917 saved_input_location = input_location;
7918 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7919 redeclare_class_template (TREE_TYPE (tmpl), parms);
7920 input_location = saved_input_location;
7924 friend_type = TREE_TYPE (tmpl);
7928 /* The friend template has not already been declared. In this
7929 case, the instantiation of the template class will cause the
7930 injection of this template into the global scope. */
7931 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7932 if (tmpl == error_mark_node)
7933 return error_mark_node;
7935 /* The new TMPL is not an instantiation of anything, so we
7936 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7937 the new type because that is supposed to be the corresponding
7938 template decl, i.e., TMPL. */
7939 DECL_USE_TEMPLATE (tmpl) = 0;
7940 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7941 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7942 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7943 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7945 /* Inject this template into the global scope. */
7946 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7949 if (context != global_namespace)
7951 if (TREE_CODE (context) == NAMESPACE_DECL)
7952 pop_nested_namespace (context);
7954 pop_nested_class ();
7960 /* Returns zero if TYPE cannot be completed later due to circularity.
7961 Otherwise returns one. */
7964 can_complete_type_without_circularity (tree type)
7966 if (type == NULL_TREE || type == error_mark_node)
7968 else if (COMPLETE_TYPE_P (type))
7970 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7971 return can_complete_type_without_circularity (TREE_TYPE (type));
7972 else if (CLASS_TYPE_P (type)
7973 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7979 /* Apply any attributes which had to be deferred until instantiation
7980 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7981 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7984 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7985 tree args, tsubst_flags_t complain, tree in_decl)
7987 tree last_dep = NULL_TREE;
7991 for (t = attributes; t; t = TREE_CHAIN (t))
7992 if (ATTR_IS_DEPENDENT (t))
7995 attributes = copy_list (attributes);
7999 if (DECL_P (*decl_p))
8001 if (TREE_TYPE (*decl_p) == error_mark_node)
8003 p = &DECL_ATTRIBUTES (*decl_p);
8006 p = &TYPE_ATTRIBUTES (*decl_p);
8010 tree late_attrs = NULL_TREE;
8011 tree *q = &late_attrs;
8013 for (*p = attributes; *p; )
8016 if (ATTR_IS_DEPENDENT (t))
8018 *p = TREE_CHAIN (t);
8019 TREE_CHAIN (t) = NULL_TREE;
8020 /* If the first attribute argument is an identifier, don't
8021 pass it through tsubst. Attributes like mode, format,
8022 cleanup and several target specific attributes expect it
8025 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8026 && TREE_VALUE (TREE_VALUE (t))
8027 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8028 == IDENTIFIER_NODE))
8031 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8033 /*integral_constant_expression_p=*/false);
8034 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8036 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8041 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8042 /*integral_constant_expression_p=*/false);
8044 q = &TREE_CHAIN (t);
8047 p = &TREE_CHAIN (t);
8050 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8054 /* Perform (or defer) access check for typedefs that were referenced
8055 from within the template TMPL code.
8056 This is a subroutine of instantiate_template and instantiate_class_template.
8057 TMPL is the template to consider and TARGS is the list of arguments of
8061 perform_typedefs_access_check (tree tmpl, tree targs)
8063 location_t saved_location;
8065 qualified_typedef_usage_t *iter;
8068 || (!CLASS_TYPE_P (tmpl)
8069 && TREE_CODE (tmpl) != FUNCTION_DECL))
8072 saved_location = input_location;
8073 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8074 get_types_needing_access_check (tmpl),
8077 tree type_decl = iter->typedef_decl;
8078 tree type_scope = iter->context;
8080 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8083 if (uses_template_parms (type_decl))
8084 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8085 if (uses_template_parms (type_scope))
8086 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8088 /* Make access check error messages point to the location
8089 of the use of the typedef. */
8090 input_location = iter->locus;
8091 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8092 type_decl, type_decl);
8094 input_location = saved_location;
8098 instantiate_class_template (tree type)
8100 tree templ, args, pattern, t, member;
8104 unsigned int saved_maximum_field_alignment;
8106 if (type == error_mark_node)
8107 return error_mark_node;
8109 if (COMPLETE_OR_OPEN_TYPE_P (type)
8110 || uses_template_parms (type))
8113 /* Figure out which template is being instantiated. */
8114 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8115 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8117 /* Determine what specialization of the original template to
8119 t = most_specialized_class (type, templ, tf_warning_or_error);
8120 if (t == error_mark_node)
8122 TYPE_BEING_DEFINED (type) = 1;
8123 return error_mark_node;
8127 /* This TYPE is actually an instantiation of a partial
8128 specialization. We replace the innermost set of ARGS with
8129 the arguments appropriate for substitution. For example,
8132 template <class T> struct S {};
8133 template <class T> struct S<T*> {};
8135 and supposing that we are instantiating S<int*>, ARGS will
8136 presently be {int*} -- but we need {int}. */
8137 pattern = TREE_TYPE (t);
8138 args = TREE_PURPOSE (t);
8142 pattern = TREE_TYPE (templ);
8143 args = CLASSTYPE_TI_ARGS (type);
8146 /* If the template we're instantiating is incomplete, then clearly
8147 there's nothing we can do. */
8148 if (!COMPLETE_TYPE_P (pattern))
8151 /* If we've recursively instantiated too many templates, stop. */
8152 if (! push_tinst_level (type))
8155 /* Now we're really doing the instantiation. Mark the type as in
8156 the process of being defined. */
8157 TYPE_BEING_DEFINED (type) = 1;
8159 /* We may be in the middle of deferred access check. Disable
8161 push_deferring_access_checks (dk_no_deferred);
8163 push_to_top_level ();
8164 /* Use #pragma pack from the template context. */
8165 saved_maximum_field_alignment = maximum_field_alignment;
8166 maximum_field_alignment = TYPE_PRECISION (pattern);
8168 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8170 /* Set the input location to the most specialized template definition.
8171 This is needed if tsubsting causes an error. */
8172 typedecl = TYPE_MAIN_DECL (pattern);
8173 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8174 DECL_SOURCE_LOCATION (typedecl);
8176 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
8177 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
8178 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
8179 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
8180 TYPE_HAS_COPY_ASSIGN (type) = TYPE_HAS_COPY_ASSIGN (pattern);
8181 TYPE_HAS_CONST_COPY_ASSIGN (type) = TYPE_HAS_CONST_COPY_ASSIGN (pattern);
8182 TYPE_HAS_COPY_CTOR (type) = TYPE_HAS_COPY_CTOR (pattern);
8183 TYPE_HAS_CONST_COPY_CTOR (type) = TYPE_HAS_CONST_COPY_CTOR (pattern);
8184 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
8185 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
8186 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8187 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8188 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8189 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8190 if (ANON_AGGR_TYPE_P (pattern))
8191 SET_ANON_AGGR_TYPE_P (type);
8192 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8194 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8195 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8198 pbinfo = TYPE_BINFO (pattern);
8200 /* We should never instantiate a nested class before its enclosing
8201 class; we need to look up the nested class by name before we can
8202 instantiate it, and that lookup should instantiate the enclosing
8204 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8205 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8207 base_list = NULL_TREE;
8208 if (BINFO_N_BASE_BINFOS (pbinfo))
8214 /* We must enter the scope containing the type, as that is where
8215 the accessibility of types named in dependent bases are
8217 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8219 /* Substitute into each of the bases to determine the actual
8221 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8224 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8225 tree expanded_bases = NULL_TREE;
8228 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8231 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8232 args, tf_error, NULL_TREE);
8233 if (expanded_bases == error_mark_node)
8236 len = TREE_VEC_LENGTH (expanded_bases);
8239 for (idx = 0; idx < len; idx++)
8242 /* Extract the already-expanded base class. */
8243 base = TREE_VEC_ELT (expanded_bases, idx);
8245 /* Substitute to figure out the base class. */
8246 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8249 if (base == error_mark_node)
8252 base_list = tree_cons (access, base, base_list);
8253 if (BINFO_VIRTUAL_P (pbase_binfo))
8254 TREE_TYPE (base_list) = integer_type_node;
8258 /* The list is now in reverse order; correct that. */
8259 base_list = nreverse (base_list);
8262 pop_scope (pushed_scope);
8264 /* Now call xref_basetypes to set up all the base-class
8266 xref_basetypes (type, base_list);
8268 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8269 (int) ATTR_FLAG_TYPE_IN_PLACE,
8270 args, tf_error, NULL_TREE);
8271 fixup_attribute_variants (type);
8273 /* Now that our base classes are set up, enter the scope of the
8274 class, so that name lookups into base classes, etc. will work
8275 correctly. This is precisely analogous to what we do in
8276 begin_class_definition when defining an ordinary non-template
8277 class, except we also need to push the enclosing classes. */
8278 push_nested_class (type);
8280 /* Now members are processed in the order of declaration. */
8281 for (member = CLASSTYPE_DECL_LIST (pattern);
8282 member; member = TREE_CHAIN (member))
8284 tree t = TREE_VALUE (member);
8286 if (TREE_PURPOSE (member))
8290 /* Build new CLASSTYPE_NESTED_UTDS. */
8293 bool class_template_p;
8295 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8296 && TYPE_LANG_SPECIFIC (t)
8297 && CLASSTYPE_IS_TEMPLATE (t));
8298 /* If the member is a class template, then -- even after
8299 substitution -- there may be dependent types in the
8300 template argument list for the class. We increment
8301 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8302 that function will assume that no types are dependent
8303 when outside of a template. */
8304 if (class_template_p)
8305 ++processing_template_decl;
8306 newtag = tsubst (t, args, tf_error, NULL_TREE);
8307 if (class_template_p)
8308 --processing_template_decl;
8309 if (newtag == error_mark_node)
8312 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8314 tree name = TYPE_IDENTIFIER (t);
8316 if (class_template_p)
8317 /* Unfortunately, lookup_template_class sets
8318 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8319 instantiation (i.e., for the type of a member
8320 template class nested within a template class.)
8321 This behavior is required for
8322 maybe_process_partial_specialization to work
8323 correctly, but is not accurate in this case;
8324 the TAG is not an instantiation of anything.
8325 (The corresponding TEMPLATE_DECL is an
8326 instantiation, but the TYPE is not.) */
8327 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8329 /* Now, we call pushtag to put this NEWTAG into the scope of
8330 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8331 pushtag calling push_template_decl. We don't have to do
8332 this for enums because it will already have been done in
8335 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8336 pushtag (name, newtag, /*tag_scope=*/ts_current);
8339 else if (TREE_CODE (t) == FUNCTION_DECL
8340 || DECL_FUNCTION_TEMPLATE_P (t))
8342 /* Build new TYPE_METHODS. */
8345 if (TREE_CODE (t) == TEMPLATE_DECL)
8346 ++processing_template_decl;
8347 r = tsubst (t, args, tf_error, NULL_TREE);
8348 if (TREE_CODE (t) == TEMPLATE_DECL)
8349 --processing_template_decl;
8350 set_current_access_from_decl (r);
8351 finish_member_declaration (r);
8355 /* Build new TYPE_FIELDS. */
8356 if (TREE_CODE (t) == STATIC_ASSERT)
8359 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8360 tf_warning_or_error, NULL_TREE,
8361 /*integral_constant_expression_p=*/true);
8362 finish_static_assert (condition,
8363 STATIC_ASSERT_MESSAGE (t),
8364 STATIC_ASSERT_SOURCE_LOCATION (t),
8367 else if (TREE_CODE (t) != CONST_DECL)
8371 /* The file and line for this declaration, to
8372 assist in error message reporting. Since we
8373 called push_tinst_level above, we don't need to
8375 input_location = DECL_SOURCE_LOCATION (t);
8377 if (TREE_CODE (t) == TEMPLATE_DECL)
8378 ++processing_template_decl;
8379 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8380 if (TREE_CODE (t) == TEMPLATE_DECL)
8381 --processing_template_decl;
8382 if (TREE_CODE (r) == VAR_DECL)
8386 [t]he initialization (and any associated
8387 side-effects) of a static data member does
8388 not occur unless the static data member is
8389 itself used in a way that requires the
8390 definition of the static data member to
8393 Therefore, we do not substitute into the
8394 initialized for the static data member here. */
8395 finish_static_data_member_decl
8398 /*init_const_expr_p=*/false,
8399 /*asmspec_tree=*/NULL_TREE,
8401 if (DECL_INITIALIZED_IN_CLASS_P (r))
8402 check_static_variable_definition (r, TREE_TYPE (r));
8404 else if (TREE_CODE (r) == FIELD_DECL)
8406 /* Determine whether R has a valid type and can be
8407 completed later. If R is invalid, then it is
8408 replaced by error_mark_node so that it will not be
8409 added to TYPE_FIELDS. */
8410 tree rtype = TREE_TYPE (r);
8411 if (can_complete_type_without_circularity (rtype))
8412 complete_type (rtype);
8414 if (!COMPLETE_TYPE_P (rtype))
8416 cxx_incomplete_type_error (r, rtype);
8417 r = error_mark_node;
8421 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8422 such a thing will already have been added to the field
8423 list by tsubst_enum in finish_member_declaration in the
8424 CLASSTYPE_NESTED_UTDS case above. */
8425 if (!(TREE_CODE (r) == TYPE_DECL
8426 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8427 && DECL_ARTIFICIAL (r)))
8429 set_current_access_from_decl (r);
8430 finish_member_declaration (r);
8437 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8439 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8441 tree friend_type = t;
8442 bool adjust_processing_template_decl = false;
8444 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8446 /* template <class T> friend class C; */
8447 friend_type = tsubst_friend_class (friend_type, args);
8448 adjust_processing_template_decl = true;
8450 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8452 /* template <class T> friend class C::D; */
8453 friend_type = tsubst (friend_type, args,
8454 tf_warning_or_error, NULL_TREE);
8455 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8456 friend_type = TREE_TYPE (friend_type);
8457 adjust_processing_template_decl = true;
8459 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
8461 /* This could be either
8465 when dependent_type_p is false or
8467 template <class U> friend class T::C;
8470 friend_type = tsubst (friend_type, args,
8471 tf_warning_or_error, NULL_TREE);
8472 /* Bump processing_template_decl for correct
8473 dependent_type_p calculation. */
8474 ++processing_template_decl;
8475 if (dependent_type_p (friend_type))
8476 adjust_processing_template_decl = true;
8477 --processing_template_decl;
8479 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8480 && hidden_name_p (TYPE_NAME (friend_type)))
8484 where C hasn't been declared yet. Let's lookup name
8485 from namespace scope directly, bypassing any name that
8486 come from dependent base class. */
8487 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8489 /* The call to xref_tag_from_type does injection for friend
8491 push_nested_namespace (ns);
8493 xref_tag_from_type (friend_type, NULL_TREE,
8494 /*tag_scope=*/ts_current);
8495 pop_nested_namespace (ns);
8497 else if (uses_template_parms (friend_type))
8498 /* friend class C<T>; */
8499 friend_type = tsubst (friend_type, args,
8500 tf_warning_or_error, NULL_TREE);
8505 where C is already declared or
8507 friend class C<int>;
8509 We don't have to do anything in these cases. */
8511 if (adjust_processing_template_decl)
8512 /* Trick make_friend_class into realizing that the friend
8513 we're adding is a template, not an ordinary class. It's
8514 important that we use make_friend_class since it will
8515 perform some error-checking and output cross-reference
8517 ++processing_template_decl;
8519 if (friend_type != error_mark_node)
8520 make_friend_class (type, friend_type, /*complain=*/false);
8522 if (adjust_processing_template_decl)
8523 --processing_template_decl;
8527 /* Build new DECL_FRIENDLIST. */
8530 /* The file and line for this declaration, to
8531 assist in error message reporting. Since we
8532 called push_tinst_level above, we don't need to
8534 input_location = DECL_SOURCE_LOCATION (t);
8536 if (TREE_CODE (t) == TEMPLATE_DECL)
8538 ++processing_template_decl;
8539 push_deferring_access_checks (dk_no_check);
8542 r = tsubst_friend_function (t, args);
8543 add_friend (type, r, /*complain=*/false);
8544 if (TREE_CODE (t) == TEMPLATE_DECL)
8546 pop_deferring_access_checks ();
8547 --processing_template_decl;
8553 /* Set the file and line number information to whatever is given for
8554 the class itself. This puts error messages involving generated
8555 implicit functions at a predictable point, and the same point
8556 that would be used for non-template classes. */
8557 input_location = DECL_SOURCE_LOCATION (typedecl);
8559 unreverse_member_declarations (type);
8560 finish_struct_1 (type);
8561 TYPE_BEING_DEFINED (type) = 0;
8563 /* We don't instantiate default arguments for member functions. 14.7.1:
8565 The implicit instantiation of a class template specialization causes
8566 the implicit instantiation of the declarations, but not of the
8567 definitions or default arguments, of the class member functions,
8568 member classes, static data members and member templates.... */
8570 /* Some typedefs referenced from within the template code need to be access
8571 checked at template instantiation time, i.e now. These types were
8572 added to the template at parsing time. Let's get those and perform
8573 the access checks then. */
8574 perform_typedefs_access_check (pattern, args);
8575 perform_deferred_access_checks ();
8576 pop_nested_class ();
8577 maximum_field_alignment = saved_maximum_field_alignment;
8578 pop_from_top_level ();
8579 pop_deferring_access_checks ();
8582 /* The vtable for a template class can be emitted in any translation
8583 unit in which the class is instantiated. When there is no key
8584 method, however, finish_struct_1 will already have added TYPE to
8585 the keyed_classes list. */
8586 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8587 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8593 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8599 else if (TYPE_P (t))
8600 r = tsubst (t, args, complain, in_decl);
8603 if (!(complain & tf_warning))
8604 ++c_inhibit_evaluation_warnings;
8605 r = tsubst_expr (t, args, complain, in_decl,
8606 /*integral_constant_expression_p=*/true);
8607 if (!(complain & tf_warning))
8608 --c_inhibit_evaluation_warnings;
8613 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8614 NONTYPE_ARGUMENT_PACK. */
8617 make_fnparm_pack (tree spec_parm)
8619 /* Collect all of the extra "packed" parameters into an
8623 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8624 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8625 int i, len = list_length (spec_parm);
8627 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8628 parmvec = make_tree_vec (len);
8629 parmtypevec = make_tree_vec (len);
8630 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
8632 TREE_VEC_ELT (parmvec, i) = spec_parm;
8633 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8636 /* Build the argument packs. */
8637 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8638 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8639 TREE_TYPE (argpack) = argtypepack;
8644 /* Substitute ARGS into T, which is an pack expansion
8645 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8646 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8647 (if only a partial substitution could be performed) or
8648 ERROR_MARK_NODE if there was an error. */
8650 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8654 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8658 htab_t saved_local_specializations = NULL;
8660 gcc_assert (PACK_EXPANSION_P (t));
8661 pattern = PACK_EXPANSION_PATTERN (t);
8663 /* Determine the argument packs that will instantiate the parameter
8664 packs used in the expansion expression. While we're at it,
8665 compute the number of arguments to be expanded and make sure it
8667 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8668 pack = TREE_CHAIN (pack))
8670 tree parm_pack = TREE_VALUE (pack);
8671 tree arg_pack = NULL_TREE;
8672 tree orig_arg = NULL_TREE;
8674 if (TREE_CODE (parm_pack) == PARM_DECL)
8676 if (!cp_unevaluated_operand)
8677 arg_pack = retrieve_local_specialization (parm_pack);
8680 /* We can't rely on local_specializations for a parameter
8681 name used later in a function declaration (such as in a
8682 late-specified return type). Even if it exists, it might
8683 have the wrong value for a recursive call. Just make a
8684 dummy decl, since it's only used for its type. */
8685 arg_pack = tsubst_decl (parm_pack, args, complain);
8686 arg_pack = make_fnparm_pack (arg_pack);
8691 int level, idx, levels;
8692 template_parm_level_and_index (parm_pack, &level, &idx);
8694 levels = TMPL_ARGS_DEPTH (args);
8695 if (level <= levels)
8696 arg_pack = TMPL_ARG (args, level, idx);
8699 orig_arg = arg_pack;
8700 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8701 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8703 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8704 /* This can only happen if we forget to expand an argument
8705 pack somewhere else. Just return an error, silently. */
8707 result = make_tree_vec (1);
8708 TREE_VEC_ELT (result, 0) = error_mark_node;
8713 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8714 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8716 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8717 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8718 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
8719 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
8720 /* The argument pack that the parameter maps to is just an
8721 expansion of the parameter itself, such as one would
8722 find in the implicit typedef of a class inside the
8723 class itself. Consider this parameter "unsubstituted",
8724 so that we will maintain the outer pack expansion. */
8725 arg_pack = NULL_TREE;
8731 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8733 /* It's all-or-nothing with incomplete argument packs. */
8734 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8735 return error_mark_node;
8737 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8742 else if (len != my_len)
8745 /* We got explicit args for some packs but not others;
8746 do nothing now and try again after deduction. */
8748 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8749 error ("mismatched argument pack lengths while expanding "
8753 error ("mismatched argument pack lengths while expanding "
8756 return error_mark_node;
8759 /* Keep track of the parameter packs and their corresponding
8761 packs = tree_cons (parm_pack, arg_pack, packs);
8762 TREE_TYPE (packs) = orig_arg;
8765 /* We can't substitute for this parameter pack. */
8766 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8768 unsubstituted_packs);
8771 /* We cannot expand this expansion expression, because we don't have
8772 all of the argument packs we need. Substitute into the pattern
8773 and return a PACK_EXPANSION_*. The caller will need to deal with
8775 if (unsubstituted_packs)
8778 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8779 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8780 /*integral_constant_expression_p=*/false);
8782 new_pat = tsubst (pattern, args, complain, in_decl);
8783 return make_pack_expansion (new_pat);
8786 /* We could not find any argument packs that work. */
8788 return error_mark_node;
8790 if (cp_unevaluated_operand)
8792 /* We're in a late-specified return type, so create our own local
8793 specializations table; the current table is either NULL or (in the
8794 case of recursive unification) might have bindings that we don't
8795 want to use or alter. */
8796 saved_local_specializations = local_specializations;
8797 local_specializations = htab_create (37,
8798 hash_local_specialization,
8799 eq_local_specializations,
8803 /* For each argument in each argument pack, substitute into the
8805 result = make_tree_vec (len + incomplete);
8806 for (i = 0; i < len + incomplete; ++i)
8808 /* For parameter pack, change the substitution of the parameter
8809 pack to the ith argument in its argument pack, then expand
8811 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8813 tree parm = TREE_PURPOSE (pack);
8815 if (TREE_CODE (parm) == PARM_DECL)
8817 /* Select the Ith argument from the pack. */
8818 tree arg = make_node (ARGUMENT_PACK_SELECT);
8819 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8820 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8822 register_local_specialization (arg, parm);
8828 template_parm_level_and_index (parm, &level, &idx);
8832 /* Select the Ith argument from the pack. */
8833 value = make_node (ARGUMENT_PACK_SELECT);
8834 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8835 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8838 /* Update the corresponding argument. */
8839 TMPL_ARG (args, level, idx) = value;
8843 /* Substitute into the PATTERN with the altered arguments. */
8844 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8845 TREE_VEC_ELT (result, i) =
8846 tsubst_expr (pattern, args, complain, in_decl,
8847 /*integral_constant_expression_p=*/false);
8849 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8852 /* When we have incomplete argument packs, the last "expanded"
8853 result is itself a pack expansion, which allows us
8854 to deduce more arguments. */
8855 TREE_VEC_ELT (result, i) =
8856 make_pack_expansion (TREE_VEC_ELT (result, i));
8858 if (TREE_VEC_ELT (result, i) == error_mark_node)
8860 result = error_mark_node;
8865 /* Update ARGS to restore the substitution from parameter packs to
8866 their argument packs. */
8867 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8869 tree parm = TREE_PURPOSE (pack);
8871 if (TREE_CODE (parm) == PARM_DECL)
8872 register_local_specialization (TREE_TYPE (pack), parm);
8876 template_parm_level_and_index (parm, &level, &idx);
8878 /* Update the corresponding argument. */
8879 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8880 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8883 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8887 if (saved_local_specializations)
8889 htab_delete (local_specializations);
8890 local_specializations = saved_local_specializations;
8896 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8897 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8898 parameter packs; all parms generated from a function parameter pack will
8899 have the same DECL_PARM_INDEX. */
8902 get_pattern_parm (tree parm, tree tmpl)
8904 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8907 if (DECL_ARTIFICIAL (parm))
8909 for (patparm = DECL_ARGUMENTS (pattern);
8910 patparm; patparm = DECL_CHAIN (patparm))
8911 if (DECL_ARTIFICIAL (patparm)
8912 && DECL_NAME (parm) == DECL_NAME (patparm))
8917 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8918 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8919 gcc_assert (DECL_PARM_INDEX (patparm)
8920 == DECL_PARM_INDEX (parm));
8926 /* Substitute ARGS into the vector or list of template arguments T. */
8929 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8932 int len = TREE_VEC_LENGTH (t);
8933 int need_new = 0, i, expanded_len_adjust = 0, out;
8934 tree *elts = XALLOCAVEC (tree, len);
8936 for (i = 0; i < len; i++)
8938 tree orig_arg = TREE_VEC_ELT (t, i);
8941 if (TREE_CODE (orig_arg) == TREE_VEC)
8942 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8943 else if (PACK_EXPANSION_P (orig_arg))
8945 /* Substitute into an expansion expression. */
8946 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8948 if (TREE_CODE (new_arg) == TREE_VEC)
8949 /* Add to the expanded length adjustment the number of
8950 expanded arguments. We subtract one from this
8951 measurement, because the argument pack expression
8952 itself is already counted as 1 in
8953 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8954 the argument pack is empty. */
8955 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8957 else if (ARGUMENT_PACK_P (orig_arg))
8959 /* Substitute into each of the arguments. */
8960 new_arg = TYPE_P (orig_arg)
8961 ? cxx_make_type (TREE_CODE (orig_arg))
8962 : make_node (TREE_CODE (orig_arg));
8964 SET_ARGUMENT_PACK_ARGS (
8966 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8967 args, complain, in_decl));
8969 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8970 new_arg = error_mark_node;
8972 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8973 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8975 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8977 if (TREE_TYPE (new_arg) == error_mark_node)
8978 new_arg = error_mark_node;
8982 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8984 if (new_arg == error_mark_node)
8985 return error_mark_node;
8988 if (new_arg != orig_arg)
8995 /* Make space for the expanded arguments coming from template
8997 t = make_tree_vec (len + expanded_len_adjust);
8998 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
8999 arguments for a member template.
9000 In that case each TREE_VEC in ORIG_T represents a level of template
9001 arguments, and ORIG_T won't carry any non defaulted argument count.
9002 It will rather be the nested TREE_VECs that will carry one.
9003 In other words, ORIG_T carries a non defaulted argument count only
9004 if it doesn't contain any nested TREE_VEC. */
9005 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9007 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9008 count += expanded_len_adjust;
9009 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9011 for (i = 0, out = 0; i < len; i++)
9013 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9014 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9015 && TREE_CODE (elts[i]) == TREE_VEC)
9019 /* Now expand the template argument pack "in place". */
9020 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9021 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9025 TREE_VEC_ELT (t, out) = elts[i];
9033 /* Return the result of substituting ARGS into the template parameters
9034 given by PARMS. If there are m levels of ARGS and m + n levels of
9035 PARMS, then the result will contain n levels of PARMS. For
9036 example, if PARMS is `template <class T> template <class U>
9037 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9038 result will be `template <int*, double, class V>'. */
9041 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9046 /* When substituting into a template, we must set
9047 PROCESSING_TEMPLATE_DECL as the template parameters may be
9048 dependent if they are based on one-another, and the dependency
9049 predicates are short-circuit outside of templates. */
9050 ++processing_template_decl;
9052 for (new_parms = &r;
9053 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9054 new_parms = &(TREE_CHAIN (*new_parms)),
9055 parms = TREE_CHAIN (parms))
9058 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9061 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9065 if (parms == error_mark_node)
9068 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9070 if (tuple == error_mark_node)
9073 TREE_VEC_ELT (new_vec, i) =
9074 tsubst_template_parm (tuple, args, complain);
9078 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9079 - TMPL_ARGS_DEPTH (args)),
9080 new_vec, NULL_TREE);
9083 --processing_template_decl;
9088 /* Return the result of substituting ARGS into one template parameter
9089 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9090 parameter and which TREE_PURPOSE is the default argument of the
9091 template parameter. */
9094 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9096 tree default_value, parm_decl;
9098 if (args == NULL_TREE
9100 || t == error_mark_node)
9103 gcc_assert (TREE_CODE (t) == TREE_LIST);
9105 default_value = TREE_PURPOSE (t);
9106 parm_decl = TREE_VALUE (t);
9108 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9109 if (TREE_CODE (parm_decl) == PARM_DECL
9110 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9111 parm_decl = error_mark_node;
9112 default_value = tsubst_template_arg (default_value, args,
9113 complain, NULL_TREE);
9115 return build_tree_list (default_value, parm_decl);
9118 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9119 type T. If T is not an aggregate or enumeration type, it is
9120 handled as if by tsubst. IN_DECL is as for tsubst. If
9121 ENTERING_SCOPE is nonzero, T is the context for a template which
9122 we are presently tsubst'ing. Return the substituted value. */
9125 tsubst_aggr_type (tree t,
9127 tsubst_flags_t complain,
9134 switch (TREE_CODE (t))
9137 if (TYPE_PTRMEMFUNC_P (t))
9138 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9140 /* Else fall through. */
9143 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9148 int saved_unevaluated_operand;
9149 int saved_inhibit_evaluation_warnings;
9151 /* In "sizeof(X<I>)" we need to evaluate "I". */
9152 saved_unevaluated_operand = cp_unevaluated_operand;
9153 cp_unevaluated_operand = 0;
9154 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9155 c_inhibit_evaluation_warnings = 0;
9157 /* First, determine the context for the type we are looking
9159 context = TYPE_CONTEXT (t);
9162 context = tsubst_aggr_type (context, args, complain,
9163 in_decl, /*entering_scope=*/1);
9164 /* If context is a nested class inside a class template,
9165 it may still need to be instantiated (c++/33959). */
9166 if (TYPE_P (context))
9167 context = complete_type (context);
9170 /* Then, figure out what arguments are appropriate for the
9171 type we are trying to find. For example, given:
9173 template <class T> struct S;
9174 template <class T, class U> void f(T, U) { S<U> su; }
9176 and supposing that we are instantiating f<int, double>,
9177 then our ARGS will be {int, double}, but, when looking up
9178 S we only want {double}. */
9179 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9181 if (argvec == error_mark_node)
9182 r = error_mark_node;
9185 r = lookup_template_class (t, argvec, in_decl, context,
9186 entering_scope, complain);
9187 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9190 cp_unevaluated_operand = saved_unevaluated_operand;
9191 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9196 /* This is not a template type, so there's nothing to do. */
9200 return tsubst (t, args, complain, in_decl);
9204 /* Substitute into the default argument ARG (a default argument for
9205 FN), which has the indicated TYPE. */
9208 tsubst_default_argument (tree fn, tree type, tree arg)
9210 tree saved_class_ptr = NULL_TREE;
9211 tree saved_class_ref = NULL_TREE;
9213 /* This can happen in invalid code. */
9214 if (TREE_CODE (arg) == DEFAULT_ARG)
9217 /* This default argument came from a template. Instantiate the
9218 default argument here, not in tsubst. In the case of
9227 we must be careful to do name lookup in the scope of S<T>,
9228 rather than in the current class. */
9229 push_access_scope (fn);
9230 /* The "this" pointer is not valid in a default argument. */
9233 saved_class_ptr = current_class_ptr;
9234 cp_function_chain->x_current_class_ptr = NULL_TREE;
9235 saved_class_ref = current_class_ref;
9236 cp_function_chain->x_current_class_ref = NULL_TREE;
9239 push_deferring_access_checks(dk_no_deferred);
9240 /* The default argument expression may cause implicitly defined
9241 member functions to be synthesized, which will result in garbage
9242 collection. We must treat this situation as if we were within
9243 the body of function so as to avoid collecting live data on the
9246 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9247 tf_warning_or_error, NULL_TREE,
9248 /*integral_constant_expression_p=*/false);
9250 pop_deferring_access_checks();
9252 /* Restore the "this" pointer. */
9255 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9256 cp_function_chain->x_current_class_ref = saved_class_ref;
9259 /* Make sure the default argument is reasonable. */
9260 arg = check_default_argument (type, arg);
9262 pop_access_scope (fn);
9267 /* Substitute into all the default arguments for FN. */
9270 tsubst_default_arguments (tree fn)
9275 tmpl_args = DECL_TI_ARGS (fn);
9277 /* If this function is not yet instantiated, we certainly don't need
9278 its default arguments. */
9279 if (uses_template_parms (tmpl_args))
9281 /* Don't do this again for clones. */
9282 if (DECL_CLONED_FUNCTION_P (fn))
9285 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9287 arg = TREE_CHAIN (arg))
9288 if (TREE_PURPOSE (arg))
9289 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9291 TREE_PURPOSE (arg));
9294 /* Substitute the ARGS into the T, which is a _DECL. Return the
9295 result of the substitution. Issue error and warning messages under
9296 control of COMPLAIN. */
9299 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9301 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9302 location_t saved_loc;
9307 /* Set the filename and linenumber to improve error-reporting. */
9308 saved_loc = input_location;
9309 input_location = DECL_SOURCE_LOCATION (t);
9311 switch (TREE_CODE (t))
9315 /* We can get here when processing a member function template,
9316 member class template, or template template parameter. */
9317 tree decl = DECL_TEMPLATE_RESULT (t);
9322 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9324 /* Template template parameter is treated here. */
9325 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9326 if (new_type == error_mark_node)
9327 RETURN (error_mark_node);
9330 DECL_CHAIN (r) = NULL_TREE;
9331 TREE_TYPE (r) = new_type;
9332 DECL_TEMPLATE_RESULT (r)
9333 = build_decl (DECL_SOURCE_LOCATION (decl),
9334 TYPE_DECL, DECL_NAME (decl), new_type);
9335 DECL_TEMPLATE_PARMS (r)
9336 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9338 TYPE_NAME (new_type) = r;
9342 /* We might already have an instance of this template.
9343 The ARGS are for the surrounding class type, so the
9344 full args contain the tsubst'd args for the context,
9345 plus the innermost args from the template decl. */
9346 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9347 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9348 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9349 /* Because this is a template, the arguments will still be
9350 dependent, even after substitution. If
9351 PROCESSING_TEMPLATE_DECL is not set, the dependency
9352 predicates will short-circuit. */
9353 ++processing_template_decl;
9354 full_args = tsubst_template_args (tmpl_args, args,
9356 --processing_template_decl;
9357 if (full_args == error_mark_node)
9358 RETURN (error_mark_node);
9360 /* If this is a default template template argument,
9361 tsubst might not have changed anything. */
9362 if (full_args == tmpl_args)
9365 hash = hash_tmpl_and_args (t, full_args);
9366 spec = retrieve_specialization (t, full_args, hash);
9367 if (spec != NULL_TREE)
9373 /* Make a new template decl. It will be similar to the
9374 original, but will record the current template arguments.
9375 We also create a new function declaration, which is just
9376 like the old one, but points to this new template, rather
9377 than the old one. */
9379 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9380 DECL_CHAIN (r) = NULL_TREE;
9382 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9384 if (TREE_CODE (decl) == TYPE_DECL)
9387 ++processing_template_decl;
9388 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9389 --processing_template_decl;
9390 if (new_type == error_mark_node)
9391 RETURN (error_mark_node);
9393 TREE_TYPE (r) = new_type;
9394 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9395 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9396 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9397 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9402 ++processing_template_decl;
9403 new_decl = tsubst (decl, args, complain, in_decl);
9404 --processing_template_decl;
9405 if (new_decl == error_mark_node)
9406 RETURN (error_mark_node);
9408 DECL_TEMPLATE_RESULT (r) = new_decl;
9409 DECL_TI_TEMPLATE (new_decl) = r;
9410 TREE_TYPE (r) = TREE_TYPE (new_decl);
9411 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9412 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9415 SET_DECL_IMPLICIT_INSTANTIATION (r);
9416 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9417 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9419 /* The template parameters for this new template are all the
9420 template parameters for the old template, except the
9421 outermost level of parameters. */
9422 DECL_TEMPLATE_PARMS (r)
9423 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9426 if (PRIMARY_TEMPLATE_P (t))
9427 DECL_PRIMARY_TEMPLATE (r) = r;
9429 if (TREE_CODE (decl) != TYPE_DECL)
9430 /* Record this non-type partial instantiation. */
9431 register_specialization (r, t,
9432 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9440 tree argvec = NULL_TREE;
9448 /* Nobody should be tsubst'ing into non-template functions. */
9449 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9451 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9456 /* If T is not dependent, just return it. We have to
9457 increment PROCESSING_TEMPLATE_DECL because
9458 value_dependent_expression_p assumes that nothing is
9459 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9460 ++processing_template_decl;
9461 dependent_p = value_dependent_expression_p (t);
9462 --processing_template_decl;
9466 /* Calculate the most general template of which R is a
9467 specialization, and the complete set of arguments used to
9469 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9470 argvec = tsubst_template_args (DECL_TI_ARGS
9471 (DECL_TEMPLATE_RESULT
9472 (DECL_TI_TEMPLATE (t))),
9473 args, complain, in_decl);
9475 /* Check to see if we already have this specialization. */
9476 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9477 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9485 /* We can see more levels of arguments than parameters if
9486 there was a specialization of a member template, like
9489 template <class T> struct S { template <class U> void f(); }
9490 template <> template <class U> void S<int>::f(U);
9492 Here, we'll be substituting into the specialization,
9493 because that's where we can find the code we actually
9494 want to generate, but we'll have enough arguments for
9495 the most general template.
9497 We also deal with the peculiar case:
9499 template <class T> struct S {
9500 template <class U> friend void f();
9502 template <class U> void f() {}
9504 template void f<double>();
9506 Here, the ARGS for the instantiation of will be {int,
9507 double}. But, we only need as many ARGS as there are
9508 levels of template parameters in CODE_PATTERN. We are
9509 careful not to get fooled into reducing the ARGS in
9512 template <class T> struct S { template <class U> void f(U); }
9513 template <class T> template <> void S<T>::f(int) {}
9515 which we can spot because the pattern will be a
9516 specialization in this case. */
9517 args_depth = TMPL_ARGS_DEPTH (args);
9519 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9520 if (args_depth > parms_depth
9521 && !DECL_TEMPLATE_SPECIALIZATION (t))
9522 args = get_innermost_template_args (args, parms_depth);
9526 /* This special case arises when we have something like this:
9528 template <class T> struct S {
9529 friend void f<int>(int, double);
9532 Here, the DECL_TI_TEMPLATE for the friend declaration
9533 will be an IDENTIFIER_NODE. We are being called from
9534 tsubst_friend_function, and we want only to create a
9535 new decl (R) with appropriate types so that we can call
9536 determine_specialization. */
9537 gen_tmpl = NULL_TREE;
9540 if (DECL_CLASS_SCOPE_P (t))
9542 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9546 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9547 complain, t, /*entering_scope=*/1);
9552 ctx = DECL_CONTEXT (t);
9554 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9555 if (type == error_mark_node)
9556 RETURN (error_mark_node);
9558 /* We do NOT check for matching decls pushed separately at this
9559 point, as they may not represent instantiations of this
9560 template, and in any case are considered separate under the
9563 DECL_USE_TEMPLATE (r) = 0;
9564 TREE_TYPE (r) = type;
9565 /* Clear out the mangled name and RTL for the instantiation. */
9566 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9567 SET_DECL_RTL (r, NULL);
9568 /* Leave DECL_INITIAL set on deleted instantiations. */
9569 if (!DECL_DELETED_FN (r))
9570 DECL_INITIAL (r) = NULL_TREE;
9571 DECL_CONTEXT (r) = ctx;
9573 if (member && DECL_CONV_FN_P (r))
9574 /* Type-conversion operator. Reconstruct the name, in
9575 case it's the name of one of the template's parameters. */
9576 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9578 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9580 DECL_RESULT (r) = NULL_TREE;
9582 TREE_STATIC (r) = 0;
9583 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9584 DECL_EXTERNAL (r) = 1;
9585 /* If this is an instantiation of a function with internal
9586 linkage, we already know what object file linkage will be
9587 assigned to the instantiation. */
9588 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9589 DECL_DEFER_OUTPUT (r) = 0;
9590 DECL_CHAIN (r) = NULL_TREE;
9591 DECL_PENDING_INLINE_INFO (r) = 0;
9592 DECL_PENDING_INLINE_P (r) = 0;
9593 DECL_SAVED_TREE (r) = NULL_TREE;
9594 DECL_STRUCT_FUNCTION (r) = NULL;
9596 /* We'll re-clone as appropriate in instantiate_template. */
9597 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9599 /* If we aren't complaining now, return on error before we register
9600 the specialization so that we'll complain eventually. */
9601 if ((complain & tf_error) == 0
9602 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9603 && !grok_op_properties (r, /*complain=*/false))
9604 RETURN (error_mark_node);
9606 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9607 this in the special friend case mentioned above where
9608 GEN_TMPL is NULL. */
9611 DECL_TEMPLATE_INFO (r)
9612 = build_template_info (gen_tmpl, argvec);
9613 SET_DECL_IMPLICIT_INSTANTIATION (r);
9614 register_specialization (r, gen_tmpl, argvec, false, hash);
9616 /* We're not supposed to instantiate default arguments
9617 until they are called, for a template. But, for a
9620 template <class T> void f ()
9621 { extern void g(int i = T()); }
9623 we should do the substitution when the template is
9624 instantiated. We handle the member function case in
9625 instantiate_class_template since the default arguments
9626 might refer to other members of the class. */
9628 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9629 && !uses_template_parms (argvec))
9630 tsubst_default_arguments (r);
9633 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9635 /* Copy the list of befriending classes. */
9636 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9638 friends = &TREE_CHAIN (*friends))
9640 *friends = copy_node (*friends);
9641 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9646 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9648 maybe_retrofit_in_chrg (r);
9649 if (DECL_CONSTRUCTOR_P (r))
9650 grok_ctor_properties (ctx, r);
9651 /* If this is an instantiation of a member template, clone it.
9652 If it isn't, that'll be handled by
9653 clone_constructors_and_destructors. */
9654 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9655 clone_function_decl (r, /*update_method_vec_p=*/0);
9657 else if ((complain & tf_error) != 0
9658 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9659 && !grok_op_properties (r, /*complain=*/true))
9660 RETURN (error_mark_node);
9662 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9663 SET_DECL_FRIEND_CONTEXT (r,
9664 tsubst (DECL_FRIEND_CONTEXT (t),
9665 args, complain, in_decl));
9667 /* Possibly limit visibility based on template args. */
9668 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9669 if (DECL_VISIBILITY_SPECIFIED (t))
9671 DECL_VISIBILITY_SPECIFIED (r) = 0;
9673 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9675 determine_visibility (r);
9676 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9677 && !processing_template_decl)
9678 defaulted_late_check (r);
9680 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9681 args, complain, in_decl);
9687 tree type = NULL_TREE;
9689 tree expanded_types = NULL_TREE;
9690 tree prev_r = NULL_TREE;
9691 tree first_r = NULL_TREE;
9693 if (FUNCTION_PARAMETER_PACK_P (t))
9695 /* If there is a local specialization that isn't a
9696 parameter pack, it means that we're doing a "simple"
9697 substitution from inside tsubst_pack_expansion. Just
9698 return the local specialization (which will be a single
9700 tree spec = retrieve_local_specialization (t);
9702 && TREE_CODE (spec) == PARM_DECL
9703 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9706 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9707 the parameters in this function parameter pack. */
9708 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9710 if (TREE_CODE (expanded_types) == TREE_VEC)
9712 len = TREE_VEC_LENGTH (expanded_types);
9714 /* Zero-length parameter packs are boring. Just substitute
9717 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9722 /* All we did was update the type. Make a note of that. */
9723 type = expanded_types;
9724 expanded_types = NULL_TREE;
9728 /* Loop through all of the parameter's we'll build. When T is
9729 a function parameter pack, LEN is the number of expanded
9730 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9732 for (i = 0; i < len; ++i)
9736 if (DECL_TEMPLATE_PARM_P (t))
9737 SET_DECL_TEMPLATE_PARM_P (r);
9739 /* An argument of a function parameter pack is not a parameter
9741 FUNCTION_PARAMETER_PACK_P (r) = false;
9744 /* We're on the Ith parameter of the function parameter
9747 /* Get the Ith type. */
9748 type = TREE_VEC_ELT (expanded_types, i);
9751 /* Rename the parameter to include the index. */
9753 make_ith_pack_parameter_name (DECL_NAME (r), i);
9756 /* We're dealing with a normal parameter. */
9757 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9759 type = type_decays_to (type);
9760 TREE_TYPE (r) = type;
9761 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9763 if (DECL_INITIAL (r))
9765 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9766 DECL_INITIAL (r) = TREE_TYPE (r);
9768 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9772 DECL_CONTEXT (r) = NULL_TREE;
9774 if (!DECL_TEMPLATE_PARM_P (r))
9775 DECL_ARG_TYPE (r) = type_passed_as (type);
9777 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9778 args, complain, in_decl);
9780 /* Keep track of the first new parameter we
9781 generate. That's what will be returned to the
9786 /* Build a proper chain of parameters when substituting
9787 into a function parameter pack. */
9789 DECL_CHAIN (prev_r) = r;
9793 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
9794 complain, DECL_CHAIN (t));
9796 /* FIRST_R contains the start of the chain we've built. */
9806 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9807 if (type == error_mark_node)
9808 RETURN (error_mark_node);
9809 TREE_TYPE (r) = type;
9810 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9812 /* DECL_INITIAL gives the number of bits in a bit-field. */
9814 = tsubst_expr (DECL_INITIAL (t), args,
9816 /*integral_constant_expression_p=*/true);
9817 /* We don't have to set DECL_CONTEXT here; it is set by
9818 finish_member_declaration. */
9819 DECL_CHAIN (r) = NULL_TREE;
9820 if (VOID_TYPE_P (type))
9821 error ("instantiation of %q+D as type %qT", r, type);
9823 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9824 args, complain, in_decl);
9829 /* We reach here only for member using decls. */
9830 if (DECL_DEPENDENT_P (t))
9832 r = do_class_using_decl
9833 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9834 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9836 r = error_mark_node;
9839 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9840 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9846 DECL_CHAIN (r) = NULL_TREE;
9853 tree argvec = NULL_TREE;
9854 tree gen_tmpl = NULL_TREE;
9856 tree tmpl = NULL_TREE;
9858 tree type = NULL_TREE;
9861 if (TREE_CODE (t) == TYPE_DECL
9862 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9864 /* If this is the canonical decl, we don't have to
9865 mess with instantiations, and often we can't (for
9866 typename, template type parms and such). Note that
9867 TYPE_NAME is not correct for the above test if
9868 we've copied the type for a typedef. */
9869 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9870 if (type == error_mark_node)
9871 RETURN (error_mark_node);
9872 r = TYPE_NAME (type);
9876 /* Check to see if we already have the specialization we
9879 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9881 /* T is a static data member or namespace-scope entity.
9882 We have to substitute into namespace-scope variables
9883 (even though such entities are never templates) because
9886 template <class T> void f() { extern T t; }
9888 where the entity referenced is not known until
9889 instantiation time. */
9891 ctx = DECL_CONTEXT (t);
9892 if (DECL_CLASS_SCOPE_P (t))
9894 ctx = tsubst_aggr_type (ctx, args,
9896 in_decl, /*entering_scope=*/1);
9897 /* If CTX is unchanged, then T is in fact the
9898 specialization we want. That situation occurs when
9899 referencing a static data member within in its own
9900 class. We can use pointer equality, rather than
9901 same_type_p, because DECL_CONTEXT is always
9903 if (ctx == DECL_CONTEXT (t))
9909 tmpl = DECL_TI_TEMPLATE (t);
9910 gen_tmpl = most_general_template (tmpl);
9911 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9912 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9913 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9918 /* A local variable. */
9920 /* Subsequent calls to pushdecl will fill this in. */
9922 spec = retrieve_local_specialization (t);
9924 /* If we already have the specialization we need, there is
9925 nothing more to do. */
9932 /* Create a new node for the specialization we need. */
9934 if (type == NULL_TREE)
9936 if (is_typedef_decl (t))
9937 type = DECL_ORIGINAL_TYPE (t);
9939 type = TREE_TYPE (t);
9940 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
9941 type = strip_array_domain (type);
9942 type = tsubst (type, args, complain, in_decl);
9944 if (TREE_CODE (r) == VAR_DECL)
9946 /* Even if the original location is out of scope, the
9947 newly substituted one is not. */
9948 DECL_DEAD_FOR_LOCAL (r) = 0;
9949 DECL_INITIALIZED_P (r) = 0;
9950 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9951 if (type == error_mark_node)
9952 RETURN (error_mark_node);
9953 if (TREE_CODE (type) == FUNCTION_TYPE)
9955 /* It may seem that this case cannot occur, since:
9960 declares a function, not a variable. However:
9963 template <typename T> void g() { T t; }
9964 template void g<f>();
9966 is an attempt to declare a variable with function
9968 error ("variable %qD has function type",
9969 /* R is not yet sufficiently initialized, so we
9970 just use its name. */
9972 RETURN (error_mark_node);
9974 type = complete_type (type);
9975 /* Wait until cp_finish_decl to set this again, to handle
9976 circular dependency (template/instantiate6.C). */
9977 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
9978 type = check_var_type (DECL_NAME (r), type);
9980 if (DECL_HAS_VALUE_EXPR_P (t))
9982 tree ve = DECL_VALUE_EXPR (t);
9983 ve = tsubst_expr (ve, args, complain, in_decl,
9984 /*constant_expression_p=*/false);
9985 SET_DECL_VALUE_EXPR (r, ve);
9988 else if (DECL_SELF_REFERENCE_P (t))
9989 SET_DECL_SELF_REFERENCE_P (r);
9990 TREE_TYPE (r) = type;
9991 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9992 DECL_CONTEXT (r) = ctx;
9993 /* Clear out the mangled name and RTL for the instantiation. */
9994 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9995 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9996 SET_DECL_RTL (r, NULL);
9997 /* The initializer must not be expanded until it is required;
9999 DECL_INITIAL (r) = NULL_TREE;
10000 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10001 SET_DECL_RTL (r, NULL);
10002 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10003 if (TREE_CODE (r) == VAR_DECL)
10005 /* Possibly limit visibility based on template args. */
10006 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10007 if (DECL_VISIBILITY_SPECIFIED (t))
10009 DECL_VISIBILITY_SPECIFIED (r) = 0;
10010 DECL_ATTRIBUTES (r)
10011 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10013 determine_visibility (r);
10018 /* A static data member declaration is always marked
10019 external when it is declared in-class, even if an
10020 initializer is present. We mimic the non-template
10021 processing here. */
10022 DECL_EXTERNAL (r) = 1;
10024 register_specialization (r, gen_tmpl, argvec, false, hash);
10025 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10026 SET_DECL_IMPLICIT_INSTANTIATION (r);
10028 else if (cp_unevaluated_operand)
10030 /* We're substituting this var in a decltype outside of its
10031 scope, such as for a lambda return type. Don't add it to
10032 local_specializations, do perform auto deduction. */
10033 tree auto_node = type_uses_auto (type);
10035 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10036 /*constant_expression_p=*/false);
10038 if (auto_node && init && describable_type (init))
10040 type = do_auto_deduction (type, init, auto_node);
10041 TREE_TYPE (r) = type;
10045 register_local_specialization (r, t);
10047 DECL_CHAIN (r) = NULL_TREE;
10049 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10051 args, complain, in_decl);
10053 /* Preserve a typedef that names a type. */
10054 if (is_typedef_decl (r))
10056 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10057 set_underlying_type (r);
10060 layout_decl (r, 0);
10065 gcc_unreachable ();
10070 /* Restore the file and line information. */
10071 input_location = saved_loc;
10076 /* Substitute into the ARG_TYPES of a function type. */
10079 tsubst_arg_types (tree arg_types,
10081 tsubst_flags_t complain,
10084 tree remaining_arg_types;
10085 tree type = NULL_TREE;
10087 tree expanded_args = NULL_TREE;
10090 if (!arg_types || arg_types == void_list_node)
10093 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10094 args, complain, in_decl);
10095 if (remaining_arg_types == error_mark_node)
10096 return error_mark_node;
10098 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10100 /* For a pack expansion, perform substitution on the
10101 entire expression. Later on, we'll handle the arguments
10103 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10104 args, complain, in_decl);
10106 if (TREE_CODE (expanded_args) == TREE_VEC)
10107 /* So that we'll spin through the parameters, one by one. */
10108 i = TREE_VEC_LENGTH (expanded_args);
10111 /* We only partially substituted into the parameter
10112 pack. Our type is TYPE_PACK_EXPANSION. */
10113 type = expanded_args;
10114 expanded_args = NULL_TREE;
10122 type = TREE_VEC_ELT (expanded_args, i);
10124 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10126 if (type == error_mark_node)
10127 return error_mark_node;
10128 if (VOID_TYPE_P (type))
10130 if (complain & tf_error)
10132 error ("invalid parameter type %qT", type);
10134 error ("in declaration %q+D", in_decl);
10136 return error_mark_node;
10139 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10140 top-level qualifiers as required. */
10141 type = TYPE_MAIN_VARIANT (type_decays_to (type));
10143 /* We do not substitute into default arguments here. The standard
10144 mandates that they be instantiated only when needed, which is
10145 done in build_over_call. */
10146 default_arg = TREE_PURPOSE (arg_types);
10148 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10150 /* We've instantiated a template before its default arguments
10151 have been parsed. This can happen for a nested template
10152 class, and is not an error unless we require the default
10153 argument in a call of this function. */
10154 remaining_arg_types =
10155 tree_cons (default_arg, type, remaining_arg_types);
10156 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10157 remaining_arg_types);
10160 remaining_arg_types =
10161 hash_tree_cons (default_arg, type, remaining_arg_types);
10164 return remaining_arg_types;
10167 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10168 *not* handle the exception-specification for FNTYPE, because the
10169 initial substitution of explicitly provided template parameters
10170 during argument deduction forbids substitution into the
10171 exception-specification:
10175 All references in the function type of the function template to the
10176 corresponding template parameters are replaced by the specified tem-
10177 plate argument values. If a substitution in a template parameter or
10178 in the function type of the function template results in an invalid
10179 type, type deduction fails. [Note: The equivalent substitution in
10180 exception specifications is done only when the function is instanti-
10181 ated, at which point a program is ill-formed if the substitution
10182 results in an invalid type.] */
10185 tsubst_function_type (tree t,
10187 tsubst_flags_t complain,
10194 /* The TYPE_CONTEXT is not used for function/method types. */
10195 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10197 /* Substitute the return type. */
10198 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10199 if (return_type == error_mark_node)
10200 return error_mark_node;
10201 /* The standard does not presently indicate that creation of a
10202 function type with an invalid return type is a deduction failure.
10203 However, that is clearly analogous to creating an array of "void"
10204 or a reference to a reference. This is core issue #486. */
10205 if (TREE_CODE (return_type) == ARRAY_TYPE
10206 || TREE_CODE (return_type) == FUNCTION_TYPE)
10208 if (complain & tf_error)
10210 if (TREE_CODE (return_type) == ARRAY_TYPE)
10211 error ("function returning an array");
10213 error ("function returning a function");
10215 return error_mark_node;
10218 /* Substitute the argument types. */
10219 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10220 complain, in_decl);
10221 if (arg_types == error_mark_node)
10222 return error_mark_node;
10224 /* Construct a new type node and return it. */
10225 if (TREE_CODE (t) == FUNCTION_TYPE)
10227 fntype = build_function_type (return_type, arg_types);
10228 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10232 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10233 if (! MAYBE_CLASS_TYPE_P (r))
10237 Type deduction may fail for any of the following
10240 -- Attempting to create "pointer to member of T" when T
10241 is not a class type. */
10242 if (complain & tf_error)
10243 error ("creating pointer to member function of non-class type %qT",
10245 return error_mark_node;
10248 fntype = build_method_type_directly (r, return_type,
10249 TREE_CHAIN (arg_types));
10251 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10256 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10257 ARGS into that specification, and return the substituted
10258 specification. If there is no specification, return NULL_TREE. */
10261 tsubst_exception_specification (tree fntype,
10263 tsubst_flags_t complain,
10269 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10270 new_specs = NULL_TREE;
10271 if (specs && TREE_PURPOSE (specs))
10273 /* A noexcept-specifier. */
10274 new_specs = tsubst_copy_and_build
10275 (TREE_PURPOSE (specs), args, complain, in_decl, /*function_p=*/false,
10276 /*integral_constant_expression_p=*/true);
10277 new_specs = build_noexcept_spec (new_specs, complain);
10281 if (! TREE_VALUE (specs))
10288 tree expanded_specs = NULL_TREE;
10290 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10292 /* Expand the pack expansion type. */
10293 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10297 if (expanded_specs == error_mark_node)
10298 return error_mark_node;
10299 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10300 len = TREE_VEC_LENGTH (expanded_specs);
10303 /* We're substituting into a member template, so
10304 we got a TYPE_PACK_EXPANSION back. Add that
10305 expansion and move on. */
10306 gcc_assert (TREE_CODE (expanded_specs)
10307 == TYPE_PACK_EXPANSION);
10308 new_specs = add_exception_specifier (new_specs,
10311 specs = TREE_CHAIN (specs);
10316 for (i = 0; i < len; ++i)
10318 if (expanded_specs)
10319 spec = TREE_VEC_ELT (expanded_specs, i);
10321 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10322 if (spec == error_mark_node)
10324 new_specs = add_exception_specifier (new_specs, spec,
10328 specs = TREE_CHAIN (specs);
10334 /* Take the tree structure T and replace template parameters used
10335 therein with the argument vector ARGS. IN_DECL is an associated
10336 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10337 Issue error and warning messages under control of COMPLAIN. Note
10338 that we must be relatively non-tolerant of extensions here, in
10339 order to preserve conformance; if we allow substitutions that
10340 should not be allowed, we may allow argument deductions that should
10341 not succeed, and therefore report ambiguous overload situations
10342 where there are none. In theory, we could allow the substitution,
10343 but indicate that it should have failed, and allow our caller to
10344 make sure that the right thing happens, but we don't try to do this
10347 This function is used for dealing with types, decls and the like;
10348 for expressions, use tsubst_expr or tsubst_copy. */
10351 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10353 enum tree_code code;
10356 if (t == NULL_TREE || t == error_mark_node
10357 || t == integer_type_node
10358 || t == void_type_node
10359 || t == char_type_node
10360 || t == unknown_type_node
10361 || TREE_CODE (t) == NAMESPACE_DECL
10362 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10366 return tsubst_decl (t, args, complain);
10368 if (args == NULL_TREE)
10371 code = TREE_CODE (t);
10373 if (code == IDENTIFIER_NODE)
10374 type = IDENTIFIER_TYPE_VALUE (t);
10376 type = TREE_TYPE (t);
10378 gcc_assert (type != unknown_type_node);
10380 /* Reuse typedefs. We need to do this to handle dependent attributes,
10381 such as attribute aligned. */
10383 && typedef_variant_p (t))
10385 tree decl = TYPE_NAME (t);
10387 if (DECL_CLASS_SCOPE_P (decl)
10388 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10389 && uses_template_parms (DECL_CONTEXT (decl)))
10391 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10392 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10393 r = retrieve_specialization (tmpl, gen_args, 0);
10395 else if (DECL_FUNCTION_SCOPE_P (decl)
10396 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10397 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10398 r = retrieve_local_specialization (decl);
10400 /* The typedef is from a non-template context. */
10406 r = cp_build_qualified_type_real
10407 (r, cp_type_quals (t) | cp_type_quals (r),
10408 complain | tf_ignore_bad_quals);
10411 /* Else we must be instantiating the typedef, so fall through. */
10415 && code != TYPENAME_TYPE
10416 && code != TEMPLATE_TYPE_PARM
10417 && code != IDENTIFIER_NODE
10418 && code != FUNCTION_TYPE
10419 && code != METHOD_TYPE)
10420 type = tsubst (type, args, complain, in_decl);
10421 if (type == error_mark_node)
10422 return error_mark_node;
10428 case ENUMERAL_TYPE:
10429 return tsubst_aggr_type (t, args, complain, in_decl,
10430 /*entering_scope=*/0);
10433 case IDENTIFIER_NODE:
10444 if (t == integer_type_node)
10447 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10448 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10452 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10454 max = tsubst_expr (omax, args, complain, in_decl,
10455 /*integral_constant_expression_p=*/false);
10457 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10459 if (TREE_CODE (max) == NOP_EXPR
10460 && TREE_SIDE_EFFECTS (omax)
10461 && !TREE_TYPE (max))
10462 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10464 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10465 with TREE_SIDE_EFFECTS that indicates this is not an integral
10466 constant expression. */
10467 if (processing_template_decl
10468 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10470 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10471 TREE_SIDE_EFFECTS (max) = 1;
10474 return compute_array_index_type (NULL_TREE, max, complain);
10477 case TEMPLATE_TYPE_PARM:
10478 case TEMPLATE_TEMPLATE_PARM:
10479 case BOUND_TEMPLATE_TEMPLATE_PARM:
10480 case TEMPLATE_PARM_INDEX:
10485 tree arg = NULL_TREE;
10489 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10490 template_parm_level_and_index (t, &level, &idx);
10492 levels = TMPL_ARGS_DEPTH (args);
10493 if (level <= levels)
10495 arg = TMPL_ARG (args, level, idx);
10497 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10498 /* See through ARGUMENT_PACK_SELECT arguments. */
10499 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10502 if (arg == error_mark_node)
10503 return error_mark_node;
10504 else if (arg != NULL_TREE)
10506 if (ARGUMENT_PACK_P (arg))
10507 /* If ARG is an argument pack, we don't actually want to
10508 perform a substitution here, because substitutions
10509 for argument packs are only done
10510 element-by-element. We can get to this point when
10511 substituting the type of a non-type template
10512 parameter pack, when that type actually contains
10513 template parameter packs from an outer template, e.g.,
10515 template<typename... Types> struct A {
10516 template<Types... Values> struct B { };
10520 if (code == TEMPLATE_TYPE_PARM)
10523 gcc_assert (TYPE_P (arg));
10525 quals = cp_type_quals (arg) | cp_type_quals (t);
10527 return cp_build_qualified_type_real
10528 (arg, quals, complain | tf_ignore_bad_quals);
10530 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10532 /* We are processing a type constructed from a
10533 template template parameter. */
10534 tree argvec = tsubst (TYPE_TI_ARGS (t),
10535 args, complain, in_decl);
10536 if (argvec == error_mark_node)
10537 return error_mark_node;
10539 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10540 are resolving nested-types in the signature of a
10541 member function templates. Otherwise ARG is a
10542 TEMPLATE_DECL and is the real template to be
10544 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10545 arg = TYPE_NAME (arg);
10547 r = lookup_template_class (arg,
10549 DECL_CONTEXT (arg),
10550 /*entering_scope=*/0,
10552 return cp_build_qualified_type_real
10553 (r, cp_type_quals (t), complain);
10556 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10557 return unshare_expr (arg);
10561 /* This can happen during the attempted tsubst'ing in
10562 unify. This means that we don't yet have any information
10563 about the template parameter in question. */
10566 /* If we get here, we must have been looking at a parm for a
10567 more deeply nested template. Make a new version of this
10568 template parameter, but with a lower level. */
10571 case TEMPLATE_TYPE_PARM:
10572 case TEMPLATE_TEMPLATE_PARM:
10573 case BOUND_TEMPLATE_TEMPLATE_PARM:
10574 if (cp_type_quals (t))
10576 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10577 r = cp_build_qualified_type_real
10578 (r, cp_type_quals (t),
10579 complain | (code == TEMPLATE_TYPE_PARM
10580 ? tf_ignore_bad_quals : 0));
10585 TEMPLATE_TYPE_PARM_INDEX (r)
10586 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10587 r, levels, args, complain);
10588 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10589 TYPE_MAIN_VARIANT (r) = r;
10590 TYPE_POINTER_TO (r) = NULL_TREE;
10591 TYPE_REFERENCE_TO (r) = NULL_TREE;
10593 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10594 /* We have reduced the level of the template
10595 template parameter, but not the levels of its
10596 template parameters, so canonical_type_parameter
10597 will not be able to find the canonical template
10598 template parameter for this level. Thus, we
10599 require structural equality checking to compare
10600 TEMPLATE_TEMPLATE_PARMs. */
10601 SET_TYPE_STRUCTURAL_EQUALITY (r);
10602 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10603 SET_TYPE_STRUCTURAL_EQUALITY (r);
10605 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10607 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10609 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10610 complain, in_decl);
10611 if (argvec == error_mark_node)
10612 return error_mark_node;
10614 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10615 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10620 case TEMPLATE_PARM_INDEX:
10621 r = reduce_template_parm_level (t, type, levels, args, complain);
10625 gcc_unreachable ();
10633 tree purpose, value, chain;
10635 if (t == void_list_node)
10638 purpose = TREE_PURPOSE (t);
10641 purpose = tsubst (purpose, args, complain, in_decl);
10642 if (purpose == error_mark_node)
10643 return error_mark_node;
10645 value = TREE_VALUE (t);
10648 value = tsubst (value, args, complain, in_decl);
10649 if (value == error_mark_node)
10650 return error_mark_node;
10652 chain = TREE_CHAIN (t);
10653 if (chain && chain != void_type_node)
10655 chain = tsubst (chain, args, complain, in_decl);
10656 if (chain == error_mark_node)
10657 return error_mark_node;
10659 if (purpose == TREE_PURPOSE (t)
10660 && value == TREE_VALUE (t)
10661 && chain == TREE_CHAIN (t))
10663 return hash_tree_cons (purpose, value, chain);
10667 /* We should never be tsubsting a binfo. */
10668 gcc_unreachable ();
10671 /* A vector of template arguments. */
10672 gcc_assert (!type);
10673 return tsubst_template_args (t, args, complain, in_decl);
10676 case REFERENCE_TYPE:
10678 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10683 Type deduction may fail for any of the following
10686 -- Attempting to create a pointer to reference type.
10687 -- Attempting to create a reference to a reference type or
10688 a reference to void.
10690 Core issue 106 says that creating a reference to a reference
10691 during instantiation is no longer a cause for failure. We
10692 only enforce this check in strict C++98 mode. */
10693 if ((TREE_CODE (type) == REFERENCE_TYPE
10694 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10695 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10697 static location_t last_loc;
10699 /* We keep track of the last time we issued this error
10700 message to avoid spewing a ton of messages during a
10701 single bad template instantiation. */
10702 if (complain & tf_error
10703 && last_loc != input_location)
10705 if (TREE_CODE (type) == VOID_TYPE)
10706 error ("forming reference to void");
10707 else if (code == POINTER_TYPE)
10708 error ("forming pointer to reference type %qT", type);
10710 error ("forming reference to reference type %qT", type);
10711 last_loc = input_location;
10714 return error_mark_node;
10716 else if (code == POINTER_TYPE)
10718 r = build_pointer_type (type);
10719 if (TREE_CODE (type) == METHOD_TYPE)
10720 r = build_ptrmemfunc_type (r);
10722 else if (TREE_CODE (type) == REFERENCE_TYPE)
10723 /* In C++0x, during template argument substitution, when there is an
10724 attempt to create a reference to a reference type, reference
10725 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10727 "If a template-argument for a template-parameter T names a type
10728 that is a reference to a type A, an attempt to create the type
10729 'lvalue reference to cv T' creates the type 'lvalue reference to
10730 A,' while an attempt to create the type type rvalue reference to
10731 cv T' creates the type T"
10733 r = cp_build_reference_type
10735 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10737 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10738 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
10740 if (r != error_mark_node)
10741 /* Will this ever be needed for TYPE_..._TO values? */
10748 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10749 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10753 Type deduction may fail for any of the following
10756 -- Attempting to create "pointer to member of T" when T
10757 is not a class type. */
10758 if (complain & tf_error)
10759 error ("creating pointer to member of non-class type %qT", r);
10760 return error_mark_node;
10762 if (TREE_CODE (type) == REFERENCE_TYPE)
10764 if (complain & tf_error)
10765 error ("creating pointer to member reference type %qT", type);
10766 return error_mark_node;
10768 if (TREE_CODE (type) == VOID_TYPE)
10770 if (complain & tf_error)
10771 error ("creating pointer to member of type void");
10772 return error_mark_node;
10774 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10775 if (TREE_CODE (type) == FUNCTION_TYPE)
10777 /* The type of the implicit object parameter gets its
10778 cv-qualifiers from the FUNCTION_TYPE. */
10780 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
10781 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10782 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10786 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10790 case FUNCTION_TYPE:
10795 fntype = tsubst_function_type (t, args, complain, in_decl);
10796 if (fntype == error_mark_node)
10797 return error_mark_node;
10799 /* Substitute the exception specification. */
10800 specs = tsubst_exception_specification (t, args, complain,
10802 if (specs == error_mark_node)
10803 return error_mark_node;
10805 fntype = build_exception_variant (fntype, specs);
10810 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10811 if (domain == error_mark_node)
10812 return error_mark_node;
10814 /* As an optimization, we avoid regenerating the array type if
10815 it will obviously be the same as T. */
10816 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10819 /* These checks should match the ones in grokdeclarator.
10823 The deduction may fail for any of the following reasons:
10825 -- Attempting to create an array with an element type that
10826 is void, a function type, or a reference type, or [DR337]
10827 an abstract class type. */
10828 if (TREE_CODE (type) == VOID_TYPE
10829 || TREE_CODE (type) == FUNCTION_TYPE
10830 || TREE_CODE (type) == REFERENCE_TYPE)
10832 if (complain & tf_error)
10833 error ("creating array of %qT", type);
10834 return error_mark_node;
10836 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10838 if (complain & tf_error)
10839 error ("creating array of %qT, which is an abstract class type",
10841 return error_mark_node;
10844 r = build_cplus_array_type (type, domain);
10846 if (TYPE_USER_ALIGN (t))
10848 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10849 TYPE_USER_ALIGN (r) = 1;
10855 case TYPENAME_TYPE:
10857 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10858 in_decl, /*entering_scope=*/1);
10859 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10860 complain, in_decl);
10862 if (ctx == error_mark_node || f == error_mark_node)
10863 return error_mark_node;
10865 if (!MAYBE_CLASS_TYPE_P (ctx))
10867 if (complain & tf_error)
10868 error ("%qT is not a class, struct, or union type", ctx);
10869 return error_mark_node;
10871 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10873 /* Normally, make_typename_type does not require that the CTX
10874 have complete type in order to allow things like:
10876 template <class T> struct S { typename S<T>::X Y; };
10878 But, such constructs have already been resolved by this
10879 point, so here CTX really should have complete type, unless
10880 it's a partial instantiation. */
10881 ctx = complete_type (ctx);
10882 if (!COMPLETE_TYPE_P (ctx))
10884 if (complain & tf_error)
10885 cxx_incomplete_type_error (NULL_TREE, ctx);
10886 return error_mark_node;
10890 f = make_typename_type (ctx, f, typename_type,
10891 (complain & tf_error) | tf_keep_type_decl);
10892 if (f == error_mark_node)
10894 if (TREE_CODE (f) == TYPE_DECL)
10896 complain |= tf_ignore_bad_quals;
10900 if (TREE_CODE (f) != TYPENAME_TYPE)
10902 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10903 error ("%qT resolves to %qT, which is not an enumeration type",
10905 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10906 error ("%qT resolves to %qT, which is is not a class type",
10910 return cp_build_qualified_type_real
10911 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10914 case UNBOUND_CLASS_TEMPLATE:
10916 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10917 in_decl, /*entering_scope=*/1);
10918 tree name = TYPE_IDENTIFIER (t);
10919 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10921 if (ctx == error_mark_node || name == error_mark_node)
10922 return error_mark_node;
10925 parm_list = tsubst_template_parms (parm_list, args, complain);
10926 return make_unbound_class_template (ctx, name, parm_list, complain);
10933 ++cp_unevaluated_operand;
10934 ++c_inhibit_evaluation_warnings;
10936 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10938 /*integral_constant_expression_p=*/false);
10940 --cp_unevaluated_operand;
10941 --c_inhibit_evaluation_warnings;
10943 type = finish_typeof (type);
10944 return cp_build_qualified_type_real (type,
10946 | cp_type_quals (type),
10950 case DECLTYPE_TYPE:
10954 ++cp_unevaluated_operand;
10955 ++c_inhibit_evaluation_warnings;
10957 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10959 /*integral_constant_expression_p=*/false);
10961 --cp_unevaluated_operand;
10962 --c_inhibit_evaluation_warnings;
10964 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10965 type = lambda_capture_field_type (type);
10966 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10967 type = lambda_return_type (type);
10969 type = finish_decltype_type
10970 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10971 return cp_build_qualified_type_real (type,
10973 | cp_type_quals (type),
10977 case TYPE_ARGUMENT_PACK:
10978 case NONTYPE_ARGUMENT_PACK:
10980 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
10982 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10986 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10988 /* For template nontype argument packs, also substitute into
10990 if (code == NONTYPE_ARGUMENT_PACK)
10991 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11009 /* We should use one of the expression tsubsts for these codes. */
11010 gcc_unreachable ();
11013 sorry ("use of %qs in template", tree_code_name [(int) code]);
11014 return error_mark_node;
11018 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11019 type of the expression on the left-hand side of the "." or "->"
11023 tsubst_baselink (tree baselink, tree object_type,
11024 tree args, tsubst_flags_t complain, tree in_decl)
11027 tree qualifying_scope;
11030 tree template_args = 0;
11031 bool template_id_p = false;
11033 /* A baselink indicates a function from a base class. Both the
11034 BASELINK_ACCESS_BINFO and the base class referenced may
11035 indicate bases of the template class, rather than the
11036 instantiated class. In addition, lookups that were not
11037 ambiguous before may be ambiguous now. Therefore, we perform
11038 the lookup again. */
11039 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11040 qualifying_scope = tsubst (qualifying_scope, args,
11041 complain, in_decl);
11042 fns = BASELINK_FUNCTIONS (baselink);
11043 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11044 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11046 template_id_p = true;
11047 template_args = TREE_OPERAND (fns, 1);
11048 fns = TREE_OPERAND (fns, 0);
11050 template_args = tsubst_template_args (template_args, args,
11051 complain, in_decl);
11053 name = DECL_NAME (get_first_fn (fns));
11054 if (IDENTIFIER_TYPENAME_P (name))
11055 name = mangle_conv_op_name_for_type (optype);
11056 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11058 return error_mark_node;
11060 /* If lookup found a single function, mark it as used at this
11061 point. (If it lookup found multiple functions the one selected
11062 later by overload resolution will be marked as used at that
11064 if (BASELINK_P (baselink))
11065 fns = BASELINK_FUNCTIONS (baselink);
11066 if (!template_id_p && !really_overloaded_fn (fns))
11067 mark_used (OVL_CURRENT (fns));
11069 /* Add back the template arguments, if present. */
11070 if (BASELINK_P (baselink) && template_id_p)
11071 BASELINK_FUNCTIONS (baselink)
11072 = build_nt (TEMPLATE_ID_EXPR,
11073 BASELINK_FUNCTIONS (baselink),
11075 /* Update the conversion operator type. */
11076 BASELINK_OPTYPE (baselink) = optype;
11079 object_type = current_class_type;
11080 return adjust_result_of_qualified_name_lookup (baselink,
11085 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11086 true if the qualified-id will be a postfix-expression in-and-of
11087 itself; false if more of the postfix-expression follows the
11088 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11092 tsubst_qualified_id (tree qualified_id, tree args,
11093 tsubst_flags_t complain, tree in_decl,
11094 bool done, bool address_p)
11100 tree template_args;
11102 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11104 /* Figure out what name to look up. */
11105 name = TREE_OPERAND (qualified_id, 1);
11106 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11108 is_template = true;
11109 template_args = TREE_OPERAND (name, 1);
11111 template_args = tsubst_template_args (template_args, args,
11112 complain, in_decl);
11113 name = TREE_OPERAND (name, 0);
11117 is_template = false;
11118 template_args = NULL_TREE;
11121 /* Substitute into the qualifying scope. When there are no ARGS, we
11122 are just trying to simplify a non-dependent expression. In that
11123 case the qualifying scope may be dependent, and, in any case,
11124 substituting will not help. */
11125 scope = TREE_OPERAND (qualified_id, 0);
11128 scope = tsubst (scope, args, complain, in_decl);
11129 expr = tsubst_copy (name, args, complain, in_decl);
11134 if (dependent_scope_p (scope))
11135 return build_qualified_name (NULL_TREE, scope, expr,
11136 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11138 if (!BASELINK_P (name) && !DECL_P (expr))
11140 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11142 /* A BIT_NOT_EXPR is used to represent a destructor. */
11143 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11145 error ("qualifying type %qT does not match destructor name ~%qT",
11146 scope, TREE_OPERAND (expr, 0));
11147 expr = error_mark_node;
11150 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11151 /*is_type_p=*/0, false);
11154 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11155 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11156 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11158 if (complain & tf_error)
11160 error ("dependent-name %qE is parsed as a non-type, but "
11161 "instantiation yields a type", qualified_id);
11162 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11164 return error_mark_node;
11170 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11172 /* Remember that there was a reference to this entity. */
11176 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11178 if (complain & tf_error)
11179 qualified_name_lookup_error (scope,
11180 TREE_OPERAND (qualified_id, 1),
11181 expr, input_location);
11182 return error_mark_node;
11186 expr = lookup_template_function (expr, template_args);
11188 if (expr == error_mark_node && complain & tf_error)
11189 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11190 expr, input_location);
11191 else if (TYPE_P (scope))
11193 expr = (adjust_result_of_qualified_name_lookup
11194 (expr, scope, current_class_type));
11195 expr = (finish_qualified_id_expr
11196 (scope, expr, done, address_p,
11197 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11198 /*template_arg_p=*/false));
11201 /* Expressions do not generally have reference type. */
11202 if (TREE_CODE (expr) != SCOPE_REF
11203 /* However, if we're about to form a pointer-to-member, we just
11204 want the referenced member referenced. */
11205 && TREE_CODE (expr) != OFFSET_REF)
11206 expr = convert_from_reference (expr);
11211 /* Like tsubst, but deals with expressions. This function just replaces
11212 template parms; to finish processing the resultant expression, use
11216 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11218 enum tree_code code;
11221 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11224 code = TREE_CODE (t);
11229 r = retrieve_local_specialization (t);
11234 /* This can happen for a parameter name used later in a function
11235 declaration (such as in a late-specified return type). Just
11236 make a dummy decl, since it's only used for its type. */
11237 gcc_assert (cp_unevaluated_operand != 0);
11238 /* We copy T because want to tsubst the PARM_DECL only,
11239 not the following PARM_DECLs that are chained to T. */
11241 r = tsubst_decl (c, args, complain);
11242 /* Give it the template pattern as its context; its true context
11243 hasn't been instantiated yet and this is good enough for
11245 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11248 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11249 r = ARGUMENT_PACK_SELECT_ARG (r);
11258 if (DECL_TEMPLATE_PARM_P (t))
11259 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11260 /* There is no need to substitute into namespace-scope
11262 if (DECL_NAMESPACE_SCOPE_P (t))
11264 /* If ARGS is NULL, then T is known to be non-dependent. */
11265 if (args == NULL_TREE)
11266 return integral_constant_value (t);
11268 /* Unfortunately, we cannot just call lookup_name here.
11271 template <int I> int f() {
11273 struct S { void g() { E e = a; } };
11276 When we instantiate f<7>::S::g(), say, lookup_name is not
11277 clever enough to find f<7>::a. */
11279 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11280 /*entering_scope=*/0);
11282 for (v = TYPE_VALUES (enum_type);
11284 v = TREE_CHAIN (v))
11285 if (TREE_PURPOSE (v) == DECL_NAME (t))
11286 return TREE_VALUE (v);
11288 /* We didn't find the name. That should never happen; if
11289 name-lookup found it during preliminary parsing, we
11290 should find it again here during instantiation. */
11291 gcc_unreachable ();
11296 if (DECL_CONTEXT (t))
11300 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11301 /*entering_scope=*/1);
11302 if (ctx != DECL_CONTEXT (t))
11304 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11307 if (complain & tf_error)
11308 error ("using invalid field %qD", t);
11309 return error_mark_node;
11318 case FUNCTION_DECL:
11319 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11320 || local_variable_p (t))
11321 t = tsubst (t, args, complain, in_decl);
11326 /* An OVERLOAD will always be a non-dependent overload set; an
11327 overload set from function scope will just be represented with an
11328 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11329 gcc_assert (!uses_template_parms (t));
11333 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11335 case TEMPLATE_DECL:
11336 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11337 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11338 args, complain, in_decl);
11339 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11340 return tsubst (t, args, complain, in_decl);
11341 else if (DECL_CLASS_SCOPE_P (t)
11342 && uses_template_parms (DECL_CONTEXT (t)))
11344 /* Template template argument like the following example need
11347 template <template <class> class TT> struct C {};
11348 template <class T> struct D {
11349 template <class U> struct E {};
11354 We are processing the template argument `E' in #1 for
11355 the template instantiation #2. Originally, `E' is a
11356 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11357 have to substitute this with one having context `D<int>'. */
11359 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11360 return lookup_field (context, DECL_NAME(t), 0, false);
11363 /* Ordinary template template argument. */
11367 case REINTERPRET_CAST_EXPR:
11368 case CONST_CAST_EXPR:
11369 case STATIC_CAST_EXPR:
11370 case DYNAMIC_CAST_EXPR:
11373 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11374 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11377 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11379 /* We only want to compute the number of arguments. */
11380 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11381 complain, in_decl);
11384 if (TREE_CODE (expanded) == TREE_VEC)
11385 len = TREE_VEC_LENGTH (expanded);
11387 if (expanded == error_mark_node)
11388 return error_mark_node;
11389 else if (PACK_EXPANSION_P (expanded)
11390 || (TREE_CODE (expanded) == TREE_VEC
11392 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11394 if (TREE_CODE (expanded) == TREE_VEC)
11395 expanded = TREE_VEC_ELT (expanded, len - 1);
11397 if (TYPE_P (expanded))
11398 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11399 complain & tf_error);
11401 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11402 complain & tf_error);
11405 return build_int_cst (size_type_node, len);
11411 case TRUTH_NOT_EXPR:
11414 case UNARY_PLUS_EXPR: /* Unary + */
11416 case AT_ENCODE_EXPR:
11420 case REALPART_EXPR:
11421 case IMAGPART_EXPR:
11423 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11424 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11426 case COMPONENT_REF:
11431 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11432 name = TREE_OPERAND (t, 1);
11433 if (TREE_CODE (name) == BIT_NOT_EXPR)
11435 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11436 complain, in_decl);
11437 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11439 else if (TREE_CODE (name) == SCOPE_REF
11440 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11442 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11443 complain, in_decl);
11444 name = TREE_OPERAND (name, 1);
11445 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11446 complain, in_decl);
11447 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11448 name = build_qualified_name (/*type=*/NULL_TREE,
11450 /*template_p=*/false);
11452 else if (TREE_CODE (name) == BASELINK)
11453 name = tsubst_baselink (name,
11454 non_reference (TREE_TYPE (object)),
11458 name = tsubst_copy (name, args, complain, in_decl);
11459 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11465 case TRUNC_DIV_EXPR:
11466 case CEIL_DIV_EXPR:
11467 case FLOOR_DIV_EXPR:
11468 case ROUND_DIV_EXPR:
11469 case EXACT_DIV_EXPR:
11473 case TRUNC_MOD_EXPR:
11474 case FLOOR_MOD_EXPR:
11475 case TRUTH_ANDIF_EXPR:
11476 case TRUTH_ORIF_EXPR:
11477 case TRUTH_AND_EXPR:
11478 case TRUTH_OR_EXPR:
11491 case COMPOUND_EXPR:
11494 case PREDECREMENT_EXPR:
11495 case PREINCREMENT_EXPR:
11496 case POSTDECREMENT_EXPR:
11497 case POSTINCREMENT_EXPR:
11499 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11500 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11503 return build_qualified_name (/*type=*/NULL_TREE,
11504 tsubst_copy (TREE_OPERAND (t, 0),
11505 args, complain, in_decl),
11506 tsubst_copy (TREE_OPERAND (t, 1),
11507 args, complain, in_decl),
11508 QUALIFIED_NAME_IS_TEMPLATE (t));
11513 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11514 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11515 NULL_TREE, NULL_TREE);
11519 int n = VL_EXP_OPERAND_LENGTH (t);
11520 tree result = build_vl_exp (CALL_EXPR, n);
11522 for (i = 0; i < n; i++)
11523 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11524 complain, in_decl);
11530 case PSEUDO_DTOR_EXPR:
11533 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11534 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11535 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11536 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11543 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11544 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11545 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11546 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11553 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11554 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11555 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11556 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11560 case TEMPLATE_ID_EXPR:
11562 /* Substituted template arguments */
11563 tree fn = TREE_OPERAND (t, 0);
11564 tree targs = TREE_OPERAND (t, 1);
11566 fn = tsubst_copy (fn, args, complain, in_decl);
11568 targs = tsubst_template_args (targs, args, complain, in_decl);
11570 return lookup_template_function (fn, targs);
11575 tree purpose, value, chain;
11577 if (t == void_list_node)
11580 purpose = TREE_PURPOSE (t);
11582 purpose = tsubst_copy (purpose, args, complain, in_decl);
11583 value = TREE_VALUE (t);
11585 value = tsubst_copy (value, args, complain, in_decl);
11586 chain = TREE_CHAIN (t);
11587 if (chain && chain != void_type_node)
11588 chain = tsubst_copy (chain, args, complain, in_decl);
11589 if (purpose == TREE_PURPOSE (t)
11590 && value == TREE_VALUE (t)
11591 && chain == TREE_CHAIN (t))
11593 return tree_cons (purpose, value, chain);
11598 case ENUMERAL_TYPE:
11600 case TEMPLATE_TYPE_PARM:
11601 case TEMPLATE_TEMPLATE_PARM:
11602 case BOUND_TEMPLATE_TEMPLATE_PARM:
11603 case TEMPLATE_PARM_INDEX:
11605 case REFERENCE_TYPE:
11607 case FUNCTION_TYPE:
11610 case TYPENAME_TYPE:
11611 case UNBOUND_CLASS_TEMPLATE:
11613 case DECLTYPE_TYPE:
11615 return tsubst (t, args, complain, in_decl);
11617 case IDENTIFIER_NODE:
11618 if (IDENTIFIER_TYPENAME_P (t))
11620 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11621 return mangle_conv_op_name_for_type (new_type);
11627 /* This is handled by tsubst_copy_and_build. */
11628 gcc_unreachable ();
11631 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11633 tsubst (TREE_TYPE (t), args, complain, in_decl));
11635 case CLEANUP_POINT_EXPR:
11636 /* We shouldn't have built any of these during initial template
11637 generation. Instead, they should be built during instantiation
11638 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11639 gcc_unreachable ();
11643 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11644 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11645 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11646 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
11647 mark_used (TREE_OPERAND (r, 1));
11650 case EXPR_PACK_EXPANSION:
11651 error ("invalid use of pack expansion expression");
11652 return error_mark_node;
11654 case NONTYPE_ARGUMENT_PACK:
11655 error ("use %<...%> to expand argument pack");
11656 return error_mark_node;
11662 /* Instantiate any typedefs in the type. */
11663 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11664 r = fold_convert (type, t);
11665 gcc_assert (TREE_CODE (r) == code);
11670 /* These can sometimes show up in a partial instantiation, but never
11671 involve template parms. */
11672 gcc_assert (!uses_template_parms (t));
11676 gcc_unreachable ();
11680 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11683 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11686 tree new_clauses = NULL, nc, oc;
11688 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11690 nc = copy_node (oc);
11691 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11694 switch (OMP_CLAUSE_CODE (nc))
11696 case OMP_CLAUSE_LASTPRIVATE:
11697 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11699 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11700 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11701 in_decl, /*integral_constant_expression_p=*/false);
11702 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11703 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11706 case OMP_CLAUSE_PRIVATE:
11707 case OMP_CLAUSE_SHARED:
11708 case OMP_CLAUSE_FIRSTPRIVATE:
11709 case OMP_CLAUSE_REDUCTION:
11710 case OMP_CLAUSE_COPYIN:
11711 case OMP_CLAUSE_COPYPRIVATE:
11712 case OMP_CLAUSE_IF:
11713 case OMP_CLAUSE_NUM_THREADS:
11714 case OMP_CLAUSE_SCHEDULE:
11715 case OMP_CLAUSE_COLLAPSE:
11716 OMP_CLAUSE_OPERAND (nc, 0)
11717 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11718 in_decl, /*integral_constant_expression_p=*/false);
11720 case OMP_CLAUSE_NOWAIT:
11721 case OMP_CLAUSE_ORDERED:
11722 case OMP_CLAUSE_DEFAULT:
11723 case OMP_CLAUSE_UNTIED:
11726 gcc_unreachable ();
11730 return finish_omp_clauses (nreverse (new_clauses));
11733 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11736 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11739 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11741 tree purpose, value, chain;
11746 if (TREE_CODE (t) != TREE_LIST)
11747 return tsubst_copy_and_build (t, args, complain, in_decl,
11748 /*function_p=*/false,
11749 /*integral_constant_expression_p=*/false);
11751 if (t == void_list_node)
11754 purpose = TREE_PURPOSE (t);
11756 purpose = RECUR (purpose);
11757 value = TREE_VALUE (t);
11758 if (value && TREE_CODE (value) != LABEL_DECL)
11759 value = RECUR (value);
11760 chain = TREE_CHAIN (t);
11761 if (chain && chain != void_type_node)
11762 chain = RECUR (chain);
11763 return tree_cons (purpose, value, chain);
11767 /* Substitute one OMP_FOR iterator. */
11770 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11771 tree condv, tree incrv, tree *clauses,
11772 tree args, tsubst_flags_t complain, tree in_decl,
11773 bool integral_constant_expression_p)
11775 #define RECUR(NODE) \
11776 tsubst_expr ((NODE), args, complain, in_decl, \
11777 integral_constant_expression_p)
11778 tree decl, init, cond, incr, auto_node;
11780 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11781 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11782 decl = RECUR (TREE_OPERAND (init, 0));
11783 init = TREE_OPERAND (init, 1);
11784 auto_node = type_uses_auto (TREE_TYPE (decl));
11785 if (auto_node && init)
11787 tree init_expr = init;
11788 if (TREE_CODE (init_expr) == DECL_EXPR)
11789 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11790 init_expr = RECUR (init_expr);
11792 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11794 gcc_assert (!type_dependent_expression_p (decl));
11796 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11798 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11799 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11800 if (TREE_CODE (incr) == MODIFY_EXPR)
11801 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11802 RECUR (TREE_OPERAND (incr, 1)),
11805 incr = RECUR (incr);
11806 TREE_VEC_ELT (declv, i) = decl;
11807 TREE_VEC_ELT (initv, i) = init;
11808 TREE_VEC_ELT (condv, i) = cond;
11809 TREE_VEC_ELT (incrv, i) = incr;
11813 if (init && TREE_CODE (init) != DECL_EXPR)
11816 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11818 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11819 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11820 && OMP_CLAUSE_DECL (c) == decl)
11822 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11823 && OMP_CLAUSE_DECL (c) == decl)
11824 error ("iteration variable %qD should not be firstprivate", decl);
11825 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11826 && OMP_CLAUSE_DECL (c) == decl)
11827 error ("iteration variable %qD should not be reduction", decl);
11831 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11832 OMP_CLAUSE_DECL (c) = decl;
11833 c = finish_omp_clauses (c);
11836 OMP_CLAUSE_CHAIN (c) = *clauses;
11841 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11842 if (COMPARISON_CLASS_P (cond))
11843 cond = build2 (TREE_CODE (cond), boolean_type_node,
11844 RECUR (TREE_OPERAND (cond, 0)),
11845 RECUR (TREE_OPERAND (cond, 1)));
11847 cond = RECUR (cond);
11848 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11849 switch (TREE_CODE (incr))
11851 case PREINCREMENT_EXPR:
11852 case PREDECREMENT_EXPR:
11853 case POSTINCREMENT_EXPR:
11854 case POSTDECREMENT_EXPR:
11855 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11856 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11859 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11860 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11862 tree rhs = TREE_OPERAND (incr, 1);
11863 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11864 RECUR (TREE_OPERAND (incr, 0)),
11865 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11866 RECUR (TREE_OPERAND (rhs, 0)),
11867 RECUR (TREE_OPERAND (rhs, 1))));
11870 incr = RECUR (incr);
11873 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11874 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11876 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11877 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11878 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11879 TREE_TYPE (decl), lhs,
11880 RECUR (TREE_OPERAND (incr, 2))));
11882 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11883 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11884 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11886 tree rhs = TREE_OPERAND (incr, 2);
11887 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11888 RECUR (TREE_OPERAND (incr, 0)),
11889 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11890 RECUR (TREE_OPERAND (rhs, 0)),
11891 RECUR (TREE_OPERAND (rhs, 1))));
11894 incr = RECUR (incr);
11897 incr = RECUR (incr);
11901 TREE_VEC_ELT (declv, i) = decl;
11902 TREE_VEC_ELT (initv, i) = init;
11903 TREE_VEC_ELT (condv, i) = cond;
11904 TREE_VEC_ELT (incrv, i) = incr;
11908 /* Like tsubst_copy for expressions, etc. but also does semantic
11912 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11913 bool integral_constant_expression_p)
11915 #define RECUR(NODE) \
11916 tsubst_expr ((NODE), args, complain, in_decl, \
11917 integral_constant_expression_p)
11921 if (t == NULL_TREE || t == error_mark_node)
11924 if (EXPR_HAS_LOCATION (t))
11925 input_location = EXPR_LOCATION (t);
11926 if (STATEMENT_CODE_P (TREE_CODE (t)))
11927 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11929 switch (TREE_CODE (t))
11931 case STATEMENT_LIST:
11933 tree_stmt_iterator i;
11934 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11935 RECUR (tsi_stmt (i));
11939 case CTOR_INITIALIZER:
11940 finish_mem_initializers (tsubst_initializer_list
11941 (TREE_OPERAND (t, 0), args));
11945 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11949 tmp = RECUR (EXPR_STMT_EXPR (t));
11950 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11951 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11953 finish_expr_stmt (tmp);
11957 do_using_directive (USING_STMT_NAMESPACE (t));
11962 tree decl, pattern_decl;
11965 pattern_decl = decl = DECL_EXPR_DECL (t);
11966 if (TREE_CODE (decl) == LABEL_DECL)
11967 finish_label_decl (DECL_NAME (decl));
11968 else if (TREE_CODE (decl) == USING_DECL)
11970 tree scope = USING_DECL_SCOPE (decl);
11971 tree name = DECL_NAME (decl);
11974 scope = tsubst (scope, args, complain, in_decl);
11975 decl = lookup_qualified_name (scope, name,
11976 /*is_type_p=*/false,
11977 /*complain=*/false);
11978 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11979 qualified_name_lookup_error (scope, name, decl, input_location);
11981 do_local_using_decl (decl, scope, name);
11985 init = DECL_INITIAL (decl);
11986 decl = tsubst (decl, args, complain, in_decl);
11987 if (decl != error_mark_node)
11989 /* By marking the declaration as instantiated, we avoid
11990 trying to instantiate it. Since instantiate_decl can't
11991 handle local variables, and since we've already done
11992 all that needs to be done, that's the right thing to
11994 if (TREE_CODE (decl) == VAR_DECL)
11995 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11996 if (TREE_CODE (decl) == VAR_DECL
11997 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11998 /* Anonymous aggregates are a special case. */
11999 finish_anon_union (decl);
12002 int const_init = false;
12003 maybe_push_decl (decl);
12004 if (TREE_CODE (decl) == VAR_DECL
12005 && DECL_PRETTY_FUNCTION_P (decl))
12007 /* For __PRETTY_FUNCTION__ we have to adjust the
12009 const char *const name
12010 = cxx_printable_name (current_function_decl, 2);
12011 init = cp_fname_init (name, &TREE_TYPE (decl));
12015 tree t = RECUR (init);
12019 /* If we had an initializer but it
12020 instantiated to nothing,
12021 value-initialize the object. This will
12022 only occur when the initializer was a
12023 pack expansion where the parameter packs
12024 used in that expansion were of length
12026 init = build_value_init (TREE_TYPE (decl),
12028 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12029 init = get_target_expr (init);
12035 if (TREE_CODE (decl) == VAR_DECL)
12036 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12038 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12043 /* A DECL_EXPR can also be used as an expression, in the condition
12044 clause of an if/for/while construct. */
12049 stmt = begin_for_stmt ();
12050 RECUR (FOR_INIT_STMT (t));
12051 finish_for_init_stmt (stmt);
12052 tmp = RECUR (FOR_COND (t));
12053 finish_for_cond (tmp, stmt);
12054 tmp = RECUR (FOR_EXPR (t));
12055 finish_for_expr (tmp, stmt);
12056 RECUR (FOR_BODY (t));
12057 finish_for_stmt (stmt);
12060 case RANGE_FOR_STMT:
12063 stmt = begin_for_stmt ();
12064 decl = RANGE_FOR_DECL (t);
12065 decl = tsubst (decl, args, complain, in_decl);
12066 maybe_push_decl (decl);
12067 expr = RECUR (RANGE_FOR_EXPR (t));
12068 stmt = cp_convert_range_for (stmt, decl, expr);
12069 RECUR (RANGE_FOR_BODY (t));
12070 finish_for_stmt (stmt);
12075 stmt = begin_while_stmt ();
12076 tmp = RECUR (WHILE_COND (t));
12077 finish_while_stmt_cond (tmp, stmt);
12078 RECUR (WHILE_BODY (t));
12079 finish_while_stmt (stmt);
12083 stmt = begin_do_stmt ();
12084 RECUR (DO_BODY (t));
12085 finish_do_body (stmt);
12086 tmp = RECUR (DO_COND (t));
12087 finish_do_stmt (tmp, stmt);
12091 stmt = begin_if_stmt ();
12092 tmp = RECUR (IF_COND (t));
12093 finish_if_stmt_cond (tmp, stmt);
12094 RECUR (THEN_CLAUSE (t));
12095 finish_then_clause (stmt);
12097 if (ELSE_CLAUSE (t))
12099 begin_else_clause (stmt);
12100 RECUR (ELSE_CLAUSE (t));
12101 finish_else_clause (stmt);
12104 finish_if_stmt (stmt);
12108 if (BIND_EXPR_BODY_BLOCK (t))
12109 stmt = begin_function_body ();
12111 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12112 ? BCS_TRY_BLOCK : 0);
12114 RECUR (BIND_EXPR_BODY (t));
12116 if (BIND_EXPR_BODY_BLOCK (t))
12117 finish_function_body (stmt);
12119 finish_compound_stmt (stmt);
12123 finish_break_stmt ();
12126 case CONTINUE_STMT:
12127 finish_continue_stmt ();
12131 stmt = begin_switch_stmt ();
12132 tmp = RECUR (SWITCH_STMT_COND (t));
12133 finish_switch_cond (tmp, stmt);
12134 RECUR (SWITCH_STMT_BODY (t));
12135 finish_switch_stmt (stmt);
12138 case CASE_LABEL_EXPR:
12139 finish_case_label (EXPR_LOCATION (t),
12140 RECUR (CASE_LOW (t)),
12141 RECUR (CASE_HIGH (t)));
12146 tree decl = LABEL_EXPR_LABEL (t);
12149 label = finish_label_stmt (DECL_NAME (decl));
12150 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12151 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12156 tmp = GOTO_DESTINATION (t);
12157 if (TREE_CODE (tmp) != LABEL_DECL)
12158 /* Computed goto's must be tsubst'd into. On the other hand,
12159 non-computed gotos must not be; the identifier in question
12160 will have no binding. */
12163 tmp = DECL_NAME (tmp);
12164 finish_goto_stmt (tmp);
12168 tmp = finish_asm_stmt
12169 (ASM_VOLATILE_P (t),
12170 RECUR (ASM_STRING (t)),
12171 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12172 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12173 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12174 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12176 tree asm_expr = tmp;
12177 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12178 asm_expr = TREE_OPERAND (asm_expr, 0);
12179 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12186 stmt = begin_try_block ();
12187 RECUR (TRY_STMTS (t));
12188 finish_cleanup_try_block (stmt);
12189 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12193 tree compound_stmt = NULL_TREE;
12195 if (FN_TRY_BLOCK_P (t))
12196 stmt = begin_function_try_block (&compound_stmt);
12198 stmt = begin_try_block ();
12200 RECUR (TRY_STMTS (t));
12202 if (FN_TRY_BLOCK_P (t))
12203 finish_function_try_block (stmt);
12205 finish_try_block (stmt);
12207 RECUR (TRY_HANDLERS (t));
12208 if (FN_TRY_BLOCK_P (t))
12209 finish_function_handler_sequence (stmt, compound_stmt);
12211 finish_handler_sequence (stmt);
12217 tree decl = HANDLER_PARMS (t);
12221 decl = tsubst (decl, args, complain, in_decl);
12222 /* Prevent instantiate_decl from trying to instantiate
12223 this variable. We've already done all that needs to be
12225 if (decl != error_mark_node)
12226 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12228 stmt = begin_handler ();
12229 finish_handler_parms (decl, stmt);
12230 RECUR (HANDLER_BODY (t));
12231 finish_handler (stmt);
12236 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12239 case STATIC_ASSERT:
12242 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12245 /*integral_constant_expression_p=*/true);
12246 finish_static_assert (condition,
12247 STATIC_ASSERT_MESSAGE (t),
12248 STATIC_ASSERT_SOURCE_LOCATION (t),
12249 /*member_p=*/false);
12254 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12255 args, complain, in_decl);
12256 stmt = begin_omp_parallel ();
12257 RECUR (OMP_PARALLEL_BODY (t));
12258 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12259 = OMP_PARALLEL_COMBINED (t);
12263 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12264 args, complain, in_decl);
12265 stmt = begin_omp_task ();
12266 RECUR (OMP_TASK_BODY (t));
12267 finish_omp_task (tmp, stmt);
12272 tree clauses, body, pre_body;
12273 tree declv, initv, condv, incrv;
12276 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12277 args, complain, in_decl);
12278 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12279 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12280 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12281 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12283 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12284 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12285 &clauses, args, complain, in_decl,
12286 integral_constant_expression_p);
12288 stmt = begin_omp_structured_block ();
12290 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12291 if (TREE_VEC_ELT (initv, i) == NULL
12292 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12293 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12294 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12296 tree init = RECUR (TREE_VEC_ELT (initv, i));
12297 gcc_assert (init == TREE_VEC_ELT (declv, i));
12298 TREE_VEC_ELT (initv, i) = NULL_TREE;
12302 tree decl_expr = TREE_VEC_ELT (initv, i);
12303 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12304 gcc_assert (init != NULL);
12305 TREE_VEC_ELT (initv, i) = RECUR (init);
12306 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12308 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12311 pre_body = push_stmt_list ();
12312 RECUR (OMP_FOR_PRE_BODY (t));
12313 pre_body = pop_stmt_list (pre_body);
12315 body = push_stmt_list ();
12316 RECUR (OMP_FOR_BODY (t));
12317 body = pop_stmt_list (body);
12319 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12320 body, pre_body, clauses);
12322 add_stmt (finish_omp_structured_block (stmt));
12328 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12329 stmt = push_stmt_list ();
12330 RECUR (OMP_BODY (t));
12331 stmt = pop_stmt_list (stmt);
12334 OMP_BODY (t) = stmt;
12335 OMP_CLAUSES (t) = tmp;
12343 stmt = push_stmt_list ();
12344 RECUR (OMP_BODY (t));
12345 stmt = pop_stmt_list (stmt);
12348 OMP_BODY (t) = stmt;
12353 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12355 tree op1 = TREE_OPERAND (t, 1);
12356 tree lhs = RECUR (TREE_OPERAND (op1, 0));
12357 tree rhs = RECUR (TREE_OPERAND (op1, 1));
12358 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
12362 case EXPR_PACK_EXPANSION:
12363 error ("invalid use of pack expansion expression");
12364 return error_mark_node;
12366 case NONTYPE_ARGUMENT_PACK:
12367 error ("use %<...%> to expand argument pack");
12368 return error_mark_node;
12371 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12373 return tsubst_copy_and_build (t, args, complain, in_decl,
12374 /*function_p=*/false,
12375 integral_constant_expression_p);
12382 /* T is a postfix-expression that is not being used in a function
12383 call. Return the substituted version of T. */
12386 tsubst_non_call_postfix_expression (tree t, tree args,
12387 tsubst_flags_t complain,
12390 if (TREE_CODE (t) == SCOPE_REF)
12391 t = tsubst_qualified_id (t, args, complain, in_decl,
12392 /*done=*/false, /*address_p=*/false);
12394 t = tsubst_copy_and_build (t, args, complain, in_decl,
12395 /*function_p=*/false,
12396 /*integral_constant_expression_p=*/false);
12401 /* Like tsubst but deals with expressions and performs semantic
12402 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12405 tsubst_copy_and_build (tree t,
12407 tsubst_flags_t complain,
12410 bool integral_constant_expression_p)
12412 #define RECUR(NODE) \
12413 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12414 /*function_p=*/false, \
12415 integral_constant_expression_p)
12419 if (t == NULL_TREE || t == error_mark_node)
12422 switch (TREE_CODE (t))
12426 /* Fall through. */
12427 case IDENTIFIER_NODE:
12431 bool non_integral_constant_expression_p;
12432 const char *error_msg;
12434 if (IDENTIFIER_TYPENAME_P (t))
12436 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12437 t = mangle_conv_op_name_for_type (new_type);
12440 /* Look up the name. */
12441 decl = lookup_name (t);
12443 /* By convention, expressions use ERROR_MARK_NODE to indicate
12444 failure, not NULL_TREE. */
12445 if (decl == NULL_TREE)
12446 decl = error_mark_node;
12448 decl = finish_id_expression (t, decl, NULL_TREE,
12450 integral_constant_expression_p,
12451 /*allow_non_integral_constant_expression_p=*/false,
12452 &non_integral_constant_expression_p,
12453 /*template_p=*/false,
12455 /*address_p=*/false,
12456 /*template_arg_p=*/false,
12461 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
12462 decl = unqualified_name_lookup_error (decl);
12466 case TEMPLATE_ID_EXPR:
12469 tree templ = RECUR (TREE_OPERAND (t, 0));
12470 tree targs = TREE_OPERAND (t, 1);
12473 targs = tsubst_template_args (targs, args, complain, in_decl);
12475 if (TREE_CODE (templ) == COMPONENT_REF)
12477 object = TREE_OPERAND (templ, 0);
12478 templ = TREE_OPERAND (templ, 1);
12481 object = NULL_TREE;
12482 templ = lookup_template_function (templ, targs);
12485 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12486 object, templ, NULL_TREE);
12488 return baselink_for_fns (templ);
12493 tree r = RECUR (TREE_OPERAND (t, 0));
12495 if (REFERENCE_REF_P (t))
12497 /* A type conversion to reference type will be enclosed in
12498 such an indirect ref, but the substitution of the cast
12499 will have also added such an indirect ref. */
12500 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12501 r = convert_from_reference (r);
12504 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12510 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12511 RECUR (TREE_OPERAND (t, 0)));
12514 case REINTERPRET_CAST_EXPR:
12515 case CONST_CAST_EXPR:
12516 case DYNAMIC_CAST_EXPR:
12517 case STATIC_CAST_EXPR:
12522 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12523 if (integral_constant_expression_p
12524 && !cast_valid_in_integral_constant_expression_p (type))
12526 if (complain & tf_error)
12527 error ("a cast to a type other than an integral or "
12528 "enumeration type cannot appear in a constant-expression");
12529 return error_mark_node;
12532 op = RECUR (TREE_OPERAND (t, 0));
12534 switch (TREE_CODE (t))
12537 return build_functional_cast (type, op, complain);
12538 case REINTERPRET_CAST_EXPR:
12539 return build_reinterpret_cast (type, op, complain);
12540 case CONST_CAST_EXPR:
12541 return build_const_cast (type, op, complain);
12542 case DYNAMIC_CAST_EXPR:
12543 return build_dynamic_cast (type, op, complain);
12544 case STATIC_CAST_EXPR:
12545 return build_static_cast (type, op, complain);
12547 gcc_unreachable ();
12551 case POSTDECREMENT_EXPR:
12552 case POSTINCREMENT_EXPR:
12553 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12554 args, complain, in_decl);
12555 return build_x_unary_op (TREE_CODE (t), op1, complain);
12557 case PREDECREMENT_EXPR:
12558 case PREINCREMENT_EXPR:
12562 case TRUTH_NOT_EXPR:
12563 case UNARY_PLUS_EXPR: /* Unary + */
12564 case REALPART_EXPR:
12565 case IMAGPART_EXPR:
12566 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12570 op1 = TREE_OPERAND (t, 0);
12571 if (TREE_CODE (op1) == LABEL_DECL)
12572 return finish_label_address_expr (DECL_NAME (op1),
12573 EXPR_LOCATION (op1));
12574 if (TREE_CODE (op1) == SCOPE_REF)
12575 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12576 /*done=*/true, /*address_p=*/true);
12578 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12580 return build_x_unary_op (ADDR_EXPR, op1, complain);
12585 case TRUNC_DIV_EXPR:
12586 case CEIL_DIV_EXPR:
12587 case FLOOR_DIV_EXPR:
12588 case ROUND_DIV_EXPR:
12589 case EXACT_DIV_EXPR:
12593 case TRUNC_MOD_EXPR:
12594 case FLOOR_MOD_EXPR:
12595 case TRUTH_ANDIF_EXPR:
12596 case TRUTH_ORIF_EXPR:
12597 case TRUTH_AND_EXPR:
12598 case TRUTH_OR_EXPR:
12613 return build_x_binary_op
12615 RECUR (TREE_OPERAND (t, 0)),
12616 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12618 : TREE_CODE (TREE_OPERAND (t, 0))),
12619 RECUR (TREE_OPERAND (t, 1)),
12620 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12622 : TREE_CODE (TREE_OPERAND (t, 1))),
12623 /*overloaded_p=*/NULL,
12627 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12628 /*address_p=*/false);
12630 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12631 args, complain, in_decl);
12632 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12635 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12636 return tsubst_copy (t, args, complain, in_decl);
12640 op1 = TREE_OPERAND (t, 0);
12643 /* When there are no ARGS, we are trying to evaluate a
12644 non-dependent expression from the parser. Trying to do
12645 the substitutions may not work. */
12647 op1 = TREE_TYPE (op1);
12651 ++cp_unevaluated_operand;
12652 ++c_inhibit_evaluation_warnings;
12653 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12654 /*function_p=*/false,
12655 /*integral_constant_expression_p=*/false);
12656 --cp_unevaluated_operand;
12657 --c_inhibit_evaluation_warnings;
12660 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12661 complain & tf_error);
12663 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12664 complain & tf_error);
12666 case AT_ENCODE_EXPR:
12668 op1 = TREE_OPERAND (t, 0);
12669 ++cp_unevaluated_operand;
12670 ++c_inhibit_evaluation_warnings;
12671 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12672 /*function_p=*/false,
12673 /*integral_constant_expression_p=*/false);
12674 --cp_unevaluated_operand;
12675 --c_inhibit_evaluation_warnings;
12676 return objc_build_encode_expr (op1);
12679 case NOEXCEPT_EXPR:
12680 op1 = TREE_OPERAND (t, 0);
12681 ++cp_unevaluated_operand;
12682 ++c_inhibit_evaluation_warnings;
12683 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12684 /*function_p=*/false,
12685 /*integral_constant_expression_p=*/false);
12686 --cp_unevaluated_operand;
12687 --c_inhibit_evaluation_warnings;
12688 return finish_noexcept_expr (op1, complain);
12692 tree r = build_x_modify_expr
12693 (RECUR (TREE_OPERAND (t, 0)),
12694 TREE_CODE (TREE_OPERAND (t, 1)),
12695 RECUR (TREE_OPERAND (t, 2)),
12697 /* TREE_NO_WARNING must be set if either the expression was
12698 parenthesized or it uses an operator such as >>= rather
12699 than plain assignment. In the former case, it was already
12700 set and must be copied. In the latter case,
12701 build_x_modify_expr sets it and it must not be reset
12703 if (TREE_NO_WARNING (t))
12704 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12709 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12710 args, complain, in_decl);
12711 /* Remember that there was a reference to this entity. */
12714 return build_x_arrow (op1);
12718 tree placement = RECUR (TREE_OPERAND (t, 0));
12719 tree init = RECUR (TREE_OPERAND (t, 3));
12720 VEC(tree,gc) *placement_vec;
12721 VEC(tree,gc) *init_vec;
12724 if (placement == NULL_TREE)
12725 placement_vec = NULL;
12728 placement_vec = make_tree_vector ();
12729 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12730 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12733 /* If there was an initializer in the original tree, but it
12734 instantiated to an empty list, then we should pass a
12735 non-NULL empty vector to tell build_new that it was an
12736 empty initializer() rather than no initializer. This can
12737 only happen when the initializer is a pack expansion whose
12738 parameter packs are of length zero. */
12739 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12743 init_vec = make_tree_vector ();
12744 if (init == void_zero_node)
12745 gcc_assert (init_vec != NULL);
12748 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12749 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12753 ret = build_new (&placement_vec,
12754 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
12755 RECUR (TREE_OPERAND (t, 2)),
12757 NEW_EXPR_USE_GLOBAL (t),
12760 if (placement_vec != NULL)
12761 release_tree_vector (placement_vec);
12762 if (init_vec != NULL)
12763 release_tree_vector (init_vec);
12769 return delete_sanity
12770 (RECUR (TREE_OPERAND (t, 0)),
12771 RECUR (TREE_OPERAND (t, 1)),
12772 DELETE_EXPR_USE_VEC (t),
12773 DELETE_EXPR_USE_GLOBAL (t));
12775 case COMPOUND_EXPR:
12776 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12777 RECUR (TREE_OPERAND (t, 1)),
12783 VEC(tree,gc) *call_args;
12784 unsigned int nargs, i;
12789 function = CALL_EXPR_FN (t);
12790 /* When we parsed the expression, we determined whether or
12791 not Koenig lookup should be performed. */
12792 koenig_p = KOENIG_LOOKUP_P (t);
12793 if (TREE_CODE (function) == SCOPE_REF)
12795 qualified_p = true;
12796 function = tsubst_qualified_id (function, args, complain, in_decl,
12798 /*address_p=*/false);
12802 if (TREE_CODE (function) == COMPONENT_REF)
12804 tree op = TREE_OPERAND (function, 1);
12806 qualified_p = (TREE_CODE (op) == SCOPE_REF
12807 || (BASELINK_P (op)
12808 && BASELINK_QUALIFIED_P (op)));
12811 qualified_p = false;
12813 function = tsubst_copy_and_build (function, args, complain,
12816 integral_constant_expression_p);
12818 if (BASELINK_P (function))
12819 qualified_p = true;
12822 nargs = call_expr_nargs (t);
12823 call_args = make_tree_vector ();
12824 for (i = 0; i < nargs; ++i)
12826 tree arg = CALL_EXPR_ARG (t, i);
12828 if (!PACK_EXPANSION_P (arg))
12829 VEC_safe_push (tree, gc, call_args,
12830 RECUR (CALL_EXPR_ARG (t, i)));
12833 /* Expand the pack expansion and push each entry onto
12835 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12836 if (TREE_CODE (arg) == TREE_VEC)
12838 unsigned int len, j;
12840 len = TREE_VEC_LENGTH (arg);
12841 for (j = 0; j < len; ++j)
12843 tree value = TREE_VEC_ELT (arg, j);
12844 if (value != NULL_TREE)
12845 value = convert_from_reference (value);
12846 VEC_safe_push (tree, gc, call_args, value);
12851 /* A partial substitution. Add one entry. */
12852 VEC_safe_push (tree, gc, call_args, arg);
12857 /* We do not perform argument-dependent lookup if normal
12858 lookup finds a non-function, in accordance with the
12859 expected resolution of DR 218. */
12861 && ((is_overloaded_fn (function)
12862 /* If lookup found a member function, the Koenig lookup is
12863 not appropriate, even if an unqualified-name was used
12864 to denote the function. */
12865 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12866 || TREE_CODE (function) == IDENTIFIER_NODE)
12867 /* Only do this when substitution turns a dependent call
12868 into a non-dependent call. */
12869 && type_dependent_expression_p_push (t)
12870 && !any_type_dependent_arguments_p (call_args))
12871 function = perform_koenig_lookup (function, call_args, false);
12873 if (TREE_CODE (function) == IDENTIFIER_NODE)
12875 unqualified_name_lookup_error (function);
12876 release_tree_vector (call_args);
12877 return error_mark_node;
12880 /* Remember that there was a reference to this entity. */
12881 if (DECL_P (function))
12882 mark_used (function);
12884 if (TREE_CODE (function) == OFFSET_REF)
12885 ret = build_offset_ref_call_from_tree (function, &call_args);
12886 else if (TREE_CODE (function) == COMPONENT_REF)
12888 tree instance = TREE_OPERAND (function, 0);
12889 tree fn = TREE_OPERAND (function, 1);
12891 if (processing_template_decl
12892 && (type_dependent_expression_p (instance)
12893 || (!BASELINK_P (fn)
12894 && TREE_CODE (fn) != FIELD_DECL)
12895 || type_dependent_expression_p (fn)
12896 || any_type_dependent_arguments_p (call_args)))
12897 ret = build_nt_call_vec (function, call_args);
12898 else if (!BASELINK_P (fn))
12899 ret = finish_call_expr (function, &call_args,
12900 /*disallow_virtual=*/false,
12901 /*koenig_p=*/false,
12904 ret = (build_new_method_call
12906 &call_args, NULL_TREE,
12907 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12912 ret = finish_call_expr (function, &call_args,
12913 /*disallow_virtual=*/qualified_p,
12917 release_tree_vector (call_args);
12923 return build_x_conditional_expr
12924 (RECUR (TREE_OPERAND (t, 0)),
12925 RECUR (TREE_OPERAND (t, 1)),
12926 RECUR (TREE_OPERAND (t, 2)),
12929 case PSEUDO_DTOR_EXPR:
12930 return finish_pseudo_destructor_expr
12931 (RECUR (TREE_OPERAND (t, 0)),
12932 RECUR (TREE_OPERAND (t, 1)),
12933 RECUR (TREE_OPERAND (t, 2)));
12937 tree purpose, value, chain;
12939 if (t == void_list_node)
12942 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12943 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12945 /* We have pack expansions, so expand those and
12946 create a new list out of it. */
12947 tree purposevec = NULL_TREE;
12948 tree valuevec = NULL_TREE;
12952 /* Expand the argument expressions. */
12953 if (TREE_PURPOSE (t))
12954 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12955 complain, in_decl);
12956 if (TREE_VALUE (t))
12957 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12958 complain, in_decl);
12960 /* Build the rest of the list. */
12961 chain = TREE_CHAIN (t);
12962 if (chain && chain != void_type_node)
12963 chain = RECUR (chain);
12965 /* Determine the number of arguments. */
12966 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12968 len = TREE_VEC_LENGTH (purposevec);
12969 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12971 else if (TREE_CODE (valuevec) == TREE_VEC)
12972 len = TREE_VEC_LENGTH (valuevec);
12975 /* Since we only performed a partial substitution into
12976 the argument pack, we only return a single list
12978 if (purposevec == TREE_PURPOSE (t)
12979 && valuevec == TREE_VALUE (t)
12980 && chain == TREE_CHAIN (t))
12983 return tree_cons (purposevec, valuevec, chain);
12986 /* Convert the argument vectors into a TREE_LIST */
12990 /* Grab the Ith values. */
12992 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12995 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12998 /* Build the list (backwards). */
12999 chain = tree_cons (purpose, value, chain);
13005 purpose = TREE_PURPOSE (t);
13007 purpose = RECUR (purpose);
13008 value = TREE_VALUE (t);
13010 value = RECUR (value);
13011 chain = TREE_CHAIN (t);
13012 if (chain && chain != void_type_node)
13013 chain = RECUR (chain);
13014 if (purpose == TREE_PURPOSE (t)
13015 && value == TREE_VALUE (t)
13016 && chain == TREE_CHAIN (t))
13018 return tree_cons (purpose, value, chain);
13021 case COMPONENT_REF:
13027 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13028 args, complain, in_decl);
13029 /* Remember that there was a reference to this entity. */
13030 if (DECL_P (object))
13031 mark_used (object);
13032 object_type = TREE_TYPE (object);
13034 member = TREE_OPERAND (t, 1);
13035 if (BASELINK_P (member))
13036 member = tsubst_baselink (member,
13037 non_reference (TREE_TYPE (object)),
13038 args, complain, in_decl);
13040 member = tsubst_copy (member, args, complain, in_decl);
13041 if (member == error_mark_node)
13042 return error_mark_node;
13044 if (object_type && !CLASS_TYPE_P (object_type))
13046 if (SCALAR_TYPE_P (object_type))
13048 tree s = NULL_TREE;
13049 tree dtor = member;
13051 if (TREE_CODE (dtor) == SCOPE_REF)
13053 s = TREE_OPERAND (dtor, 0);
13054 dtor = TREE_OPERAND (dtor, 1);
13056 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13058 dtor = TREE_OPERAND (dtor, 0);
13060 return finish_pseudo_destructor_expr (object, s, dtor);
13064 else if (TREE_CODE (member) == SCOPE_REF
13065 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13070 /* Lookup the template functions now that we know what the
13072 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13073 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13074 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13075 /*is_type_p=*/false,
13076 /*complain=*/false);
13077 if (BASELINK_P (member))
13079 BASELINK_FUNCTIONS (member)
13080 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13082 member = (adjust_result_of_qualified_name_lookup
13083 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13088 qualified_name_lookup_error (object_type, tmpl, member,
13090 return error_mark_node;
13093 else if (TREE_CODE (member) == SCOPE_REF
13094 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13095 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13097 if (complain & tf_error)
13099 if (TYPE_P (TREE_OPERAND (member, 0)))
13100 error ("%qT is not a class or namespace",
13101 TREE_OPERAND (member, 0));
13103 error ("%qD is not a class or namespace",
13104 TREE_OPERAND (member, 0));
13106 return error_mark_node;
13108 else if (TREE_CODE (member) == FIELD_DECL)
13109 return finish_non_static_data_member (member, object, NULL_TREE);
13111 return finish_class_member_access_expr (object, member,
13112 /*template_p=*/false,
13118 (RECUR (TREE_OPERAND (t, 0)));
13122 VEC(constructor_elt,gc) *n;
13123 constructor_elt *ce;
13124 unsigned HOST_WIDE_INT idx;
13125 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13126 bool process_index_p;
13128 bool need_copy_p = false;
13131 if (type == error_mark_node)
13132 return error_mark_node;
13134 /* digest_init will do the wrong thing if we let it. */
13135 if (type && TYPE_PTRMEMFUNC_P (type))
13138 /* We do not want to process the index of aggregate
13139 initializers as they are identifier nodes which will be
13140 looked up by digest_init. */
13141 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13143 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13144 newlen = VEC_length (constructor_elt, n);
13145 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13147 if (ce->index && process_index_p)
13148 ce->index = RECUR (ce->index);
13150 if (PACK_EXPANSION_P (ce->value))
13152 /* Substitute into the pack expansion. */
13153 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13156 if (ce->value == error_mark_node)
13158 else if (TREE_VEC_LENGTH (ce->value) == 1)
13159 /* Just move the argument into place. */
13160 ce->value = TREE_VEC_ELT (ce->value, 0);
13163 /* Update the length of the final CONSTRUCTOR
13164 arguments vector, and note that we will need to
13166 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13167 need_copy_p = true;
13171 ce->value = RECUR (ce->value);
13176 VEC(constructor_elt,gc) *old_n = n;
13178 n = VEC_alloc (constructor_elt, gc, newlen);
13179 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13181 if (TREE_CODE (ce->value) == TREE_VEC)
13183 int i, len = TREE_VEC_LENGTH (ce->value);
13184 for (i = 0; i < len; ++i)
13185 CONSTRUCTOR_APPEND_ELT (n, 0,
13186 TREE_VEC_ELT (ce->value, i));
13189 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13193 r = build_constructor (init_list_type_node, n);
13194 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13196 if (TREE_HAS_CONSTRUCTOR (t))
13197 return finish_compound_literal (type, r);
13204 tree operand_0 = TREE_OPERAND (t, 0);
13205 if (TYPE_P (operand_0))
13207 operand_0 = tsubst (operand_0, args, complain, in_decl);
13208 return get_typeid (operand_0);
13212 operand_0 = RECUR (operand_0);
13213 return build_typeid (operand_0);
13224 tree r = tsubst_copy (t, args, complain, in_decl);
13226 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13227 /* If the original type was a reference, we'll be wrapped in
13228 the appropriate INDIRECT_REF. */
13229 r = convert_from_reference (r);
13234 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13235 tsubst_copy (TREE_TYPE (t), args, complain,
13238 case OFFSETOF_EXPR:
13239 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13243 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13244 complain, in_decl);
13246 tree type2 = TRAIT_EXPR_TYPE2 (t);
13248 type2 = tsubst_copy (type2, args, complain, in_decl);
13250 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13255 tree old_stmt_expr = cur_stmt_expr;
13256 tree stmt_expr = begin_stmt_expr ();
13258 cur_stmt_expr = stmt_expr;
13259 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13260 integral_constant_expression_p);
13261 stmt_expr = finish_stmt_expr (stmt_expr, false);
13262 cur_stmt_expr = old_stmt_expr;
13264 /* If the resulting list of expression statement is empty,
13265 fold it further into void_zero_node. */
13266 if (empty_expr_stmt_p (stmt_expr))
13267 stmt_expr = void_zero_node;
13273 t = tsubst_copy (t, args, complain, in_decl);
13274 /* As in finish_id_expression, we resolve enumeration constants
13275 to their underlying values. */
13276 if (TREE_CODE (t) == CONST_DECL)
13278 used_types_insert (TREE_TYPE (t));
13279 return DECL_INITIAL (t);
13285 tree r = build_lambda_expr ();
13287 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13288 TREE_TYPE (r) = type;
13289 CLASSTYPE_LAMBDA_EXPR (type) = r;
13291 LAMBDA_EXPR_LOCATION (r)
13292 = LAMBDA_EXPR_LOCATION (t);
13293 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13294 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13295 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13296 LAMBDA_EXPR_DISCRIMINATOR (r)
13297 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13298 LAMBDA_EXPR_CAPTURE_LIST (r)
13299 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13300 LAMBDA_EXPR_THIS_CAPTURE (r)
13301 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
13302 LAMBDA_EXPR_EXTRA_SCOPE (r)
13303 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13305 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13306 determine_visibility (TYPE_NAME (type));
13307 /* Now that we know visibility, instantiate the type so we have a
13308 declaration of the op() for later calls to lambda_function. */
13309 complete_type (type);
13311 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13313 apply_lambda_return_type (r, type);
13315 return build_lambda_object (r);
13319 /* Handle Objective-C++ constructs, if appropriate. */
13322 = objcp_tsubst_copy_and_build (t, args, complain,
13323 in_decl, /*function_p=*/false);
13327 return tsubst_copy (t, args, complain, in_decl);
13333 /* Verify that the instantiated ARGS are valid. For type arguments,
13334 make sure that the type's linkage is ok. For non-type arguments,
13335 make sure they are constants if they are integral or enumerations.
13336 Emit an error under control of COMPLAIN, and return TRUE on error. */
13339 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13341 if (ARGUMENT_PACK_P (t))
13343 tree vec = ARGUMENT_PACK_ARGS (t);
13344 int len = TREE_VEC_LENGTH (vec);
13345 bool result = false;
13348 for (i = 0; i < len; ++i)
13349 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13353 else if (TYPE_P (t))
13355 /* [basic.link]: A name with no linkage (notably, the name
13356 of a class or enumeration declared in a local scope)
13357 shall not be used to declare an entity with linkage.
13358 This implies that names with no linkage cannot be used as
13361 DR 757 relaxes this restriction for C++0x. */
13362 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13363 : no_linkage_check (t, /*relaxed_p=*/false));
13367 /* DR 488 makes use of a type with no linkage cause
13368 type deduction to fail. */
13369 if (complain & tf_error)
13371 if (TYPE_ANONYMOUS_P (nt))
13372 error ("%qT is/uses anonymous type", t);
13374 error ("template argument for %qD uses local type %qT",
13379 /* In order to avoid all sorts of complications, we do not
13380 allow variably-modified types as template arguments. */
13381 else if (variably_modified_type_p (t, NULL_TREE))
13383 if (complain & tf_error)
13384 error ("%qT is a variably modified type", t);
13388 /* A non-type argument of integral or enumerated type must be a
13390 else if (TREE_TYPE (t)
13391 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
13392 && !TREE_CONSTANT (t))
13394 if (complain & tf_error)
13395 error ("integral expression %qE is not constant", t);
13402 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
13404 int ix, len = DECL_NTPARMS (tmpl);
13405 bool result = false;
13407 for (ix = 0; ix != len; ix++)
13409 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
13412 if (result && (complain & tf_error))
13413 error (" trying to instantiate %qD", tmpl);
13417 /* Instantiate the indicated variable or function template TMPL with
13418 the template arguments in TARG_PTR. */
13421 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
13423 tree targ_ptr = orig_args;
13427 HOST_WIDE_INT saved_processing_template_decl;
13429 if (tmpl == error_mark_node)
13430 return error_mark_node;
13432 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
13434 /* If this function is a clone, handle it specially. */
13435 if (DECL_CLONED_FUNCTION_P (tmpl))
13440 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
13441 DECL_CLONED_FUNCTION. */
13442 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
13443 targ_ptr, complain);
13444 if (spec == error_mark_node)
13445 return error_mark_node;
13447 /* Look for the clone. */
13448 FOR_EACH_CLONE (clone, spec)
13449 if (DECL_NAME (clone) == DECL_NAME (tmpl))
13451 /* We should always have found the clone by now. */
13452 gcc_unreachable ();
13456 /* Check to see if we already have this specialization. */
13457 gen_tmpl = most_general_template (tmpl);
13458 if (tmpl != gen_tmpl)
13459 /* The TMPL is a partial instantiation. To get a full set of
13460 arguments we must add the arguments used to perform the
13461 partial instantiation. */
13462 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
13465 /* It would be nice to avoid hashing here and then again in tsubst_decl,
13466 but it doesn't seem to be on the hot path. */
13467 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
13469 gcc_assert (tmpl == gen_tmpl
13470 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
13472 || fndecl == NULL_TREE);
13474 if (spec != NULL_TREE)
13477 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
13479 return error_mark_node;
13481 /* We are building a FUNCTION_DECL, during which the access of its
13482 parameters and return types have to be checked. However this
13483 FUNCTION_DECL which is the desired context for access checking
13484 is not built yet. We solve this chicken-and-egg problem by
13485 deferring all checks until we have the FUNCTION_DECL. */
13486 push_deferring_access_checks (dk_deferred);
13488 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
13489 (because, for example, we have encountered a non-dependent
13490 function call in the body of a template function and must now
13491 determine which of several overloaded functions will be called),
13492 within the instantiation itself we are not processing a
13494 saved_processing_template_decl = processing_template_decl;
13495 processing_template_decl = 0;
13496 /* Substitute template parameters to obtain the specialization. */
13497 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
13498 targ_ptr, complain, gen_tmpl);
13499 processing_template_decl = saved_processing_template_decl;
13500 if (fndecl == error_mark_node)
13501 return error_mark_node;
13503 /* Now we know the specialization, compute access previously
13505 push_access_scope (fndecl);
13507 /* Some typedefs referenced from within the template code need to be access
13508 checked at template instantiation time, i.e now. These types were
13509 added to the template at parsing time. Let's get those and perfom
13510 the acces checks then. */
13511 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13512 perform_deferred_access_checks ();
13513 pop_access_scope (fndecl);
13514 pop_deferring_access_checks ();
13516 /* The DECL_TI_TEMPLATE should always be the immediate parent
13517 template, not the most general template. */
13518 DECL_TI_TEMPLATE (fndecl) = tmpl;
13520 /* If we've just instantiated the main entry point for a function,
13521 instantiate all the alternate entry points as well. We do this
13522 by cloning the instantiation of the main entry point, not by
13523 instantiating the template clones. */
13524 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
13525 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13530 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13531 NARGS elements of the arguments that are being used when calling
13532 it. TARGS is a vector into which the deduced template arguments
13535 Return zero for success, 2 for an incomplete match that doesn't resolve
13536 all the types, and 1 for complete failure. An error message will be
13537 printed only for an incomplete match.
13539 If FN is a conversion operator, or we are trying to produce a specific
13540 specialization, RETURN_TYPE is the return type desired.
13542 The EXPLICIT_TARGS are explicit template arguments provided via a
13545 The parameter STRICT is one of:
13548 We are deducing arguments for a function call, as in
13549 [temp.deduct.call].
13552 We are deducing arguments for a conversion function, as in
13553 [temp.deduct.conv].
13556 We are deducing arguments when doing an explicit instantiation
13557 as in [temp.explicit], when determining an explicit specialization
13558 as in [temp.expl.spec], or when taking the address of a function
13559 template, as in [temp.deduct.funcaddr]. */
13562 fn_type_unification (tree fn,
13563 tree explicit_targs,
13566 unsigned int nargs,
13568 unification_kind_t strict,
13574 bool incomplete_argument_packs_p = false;
13576 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13578 fntype = TREE_TYPE (fn);
13579 if (explicit_targs)
13583 The specified template arguments must match the template
13584 parameters in kind (i.e., type, nontype, template), and there
13585 must not be more arguments than there are parameters;
13586 otherwise type deduction fails.
13588 Nontype arguments must match the types of the corresponding
13589 nontype template parameters, or must be convertible to the
13590 types of the corresponding nontype parameters as specified in
13591 _temp.arg.nontype_, otherwise type deduction fails.
13593 All references in the function type of the function template
13594 to the corresponding template parameters are replaced by the
13595 specified template argument values. If a substitution in a
13596 template parameter or in the function type of the function
13597 template results in an invalid type, type deduction fails. */
13598 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13599 int i, len = TREE_VEC_LENGTH (tparms);
13600 tree converted_args;
13601 bool incomplete = false;
13603 if (explicit_targs == error_mark_node)
13607 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13608 /*require_all_args=*/false,
13609 /*use_default_args=*/false));
13610 if (converted_args == error_mark_node)
13613 /* Substitute the explicit args into the function type. This is
13614 necessary so that, for instance, explicitly declared function
13615 arguments can match null pointed constants. If we were given
13616 an incomplete set of explicit args, we must not do semantic
13617 processing during substitution as we could create partial
13619 for (i = 0; i < len; i++)
13621 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13622 bool parameter_pack = false;
13624 /* Dig out the actual parm. */
13625 if (TREE_CODE (parm) == TYPE_DECL
13626 || TREE_CODE (parm) == TEMPLATE_DECL)
13628 parm = TREE_TYPE (parm);
13629 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13631 else if (TREE_CODE (parm) == PARM_DECL)
13633 parm = DECL_INITIAL (parm);
13634 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13637 if (parameter_pack)
13641 template_parm_level_and_index (parm, &level, &idx);
13643 /* Mark the argument pack as "incomplete". We could
13644 still deduce more arguments during unification. */
13645 targ = TMPL_ARG (converted_args, level, idx);
13648 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13649 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13650 = ARGUMENT_PACK_ARGS (targ);
13653 /* We have some incomplete argument packs. */
13654 incomplete_argument_packs_p = true;
13658 if (incomplete_argument_packs_p)
13659 /* Any substitution is guaranteed to be incomplete if there
13660 are incomplete argument packs, because we can still deduce
13664 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13666 processing_template_decl += incomplete;
13667 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
13668 processing_template_decl -= incomplete;
13670 if (fntype == error_mark_node)
13673 /* Place the explicitly specified arguments in TARGS. */
13674 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13675 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13678 /* Never do unification on the 'this' parameter. */
13679 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13685 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13686 new_args = XALLOCAVEC (tree, nargs + 1);
13687 new_args[0] = return_type;
13688 memcpy (new_args + 1, args, nargs * sizeof (tree));
13693 /* We allow incomplete unification without an error message here
13694 because the standard doesn't seem to explicitly prohibit it. Our
13695 callers must be ready to deal with unification failures in any
13697 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13698 targs, parms, args, nargs, /*subr=*/0,
13701 if (result == 0 && incomplete_argument_packs_p)
13703 int i, len = NUM_TMPL_ARGS (targs);
13705 /* Clear the "incomplete" flags on all argument packs. */
13706 for (i = 0; i < len; i++)
13708 tree arg = TREE_VEC_ELT (targs, i);
13709 if (ARGUMENT_PACK_P (arg))
13711 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
13712 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
13717 /* Now that we have bindings for all of the template arguments,
13718 ensure that the arguments deduced for the template template
13719 parameters have compatible template parameter lists. We cannot
13720 check this property before we have deduced all template
13721 arguments, because the template parameter types of a template
13722 template parameter might depend on prior template parameters
13723 deduced after the template template parameter. The following
13724 ill-formed example illustrates this issue:
13726 template<typename T, template<T> class C> void f(C<5>, T);
13728 template<int N> struct X {};
13731 f(X<5>(), 5l); // error: template argument deduction fails
13734 The template parameter list of 'C' depends on the template type
13735 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13736 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13737 time that we deduce 'C'. */
13739 && !template_template_parm_bindings_ok_p
13740 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
13744 /* All is well so far. Now, check:
13748 When all template arguments have been deduced, all uses of
13749 template parameters in nondeduced contexts are replaced with
13750 the corresponding deduced argument values. If the
13751 substitution results in an invalid type, as described above,
13752 type deduction fails. */
13754 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
13755 if (substed == error_mark_node)
13758 /* If we're looking for an exact match, check that what we got
13759 is indeed an exact match. It might not be if some template
13760 parameters are used in non-deduced contexts. */
13761 if (strict == DEDUCE_EXACT)
13766 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
13768 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
13769 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
13770 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13778 /* Adjust types before performing type deduction, as described in
13779 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
13780 sections are symmetric. PARM is the type of a function parameter
13781 or the return type of the conversion function. ARG is the type of
13782 the argument passed to the call, or the type of the value
13783 initialized with the result of the conversion function.
13784 ARG_EXPR is the original argument expression, which may be null. */
13787 maybe_adjust_types_for_deduction (unification_kind_t strict,
13801 /* Swap PARM and ARG throughout the remainder of this
13802 function; the handling is precisely symmetric since PARM
13803 will initialize ARG rather than vice versa. */
13811 /* Core issue #873: Do the DR606 thing (see below) for these cases,
13812 too, but here handle it by stripping the reference from PARM
13813 rather than by adding it to ARG. */
13814 if (TREE_CODE (*parm) == REFERENCE_TYPE
13815 && TYPE_REF_IS_RVALUE (*parm)
13816 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13817 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13818 && TREE_CODE (*arg) == REFERENCE_TYPE
13819 && !TYPE_REF_IS_RVALUE (*arg))
13820 *parm = TREE_TYPE (*parm);
13821 /* Nothing else to do in this case. */
13825 gcc_unreachable ();
13828 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13830 /* [temp.deduct.call]
13832 If P is not a reference type:
13834 --If A is an array type, the pointer type produced by the
13835 array-to-pointer standard conversion (_conv.array_) is
13836 used in place of A for type deduction; otherwise,
13838 --If A is a function type, the pointer type produced by
13839 the function-to-pointer standard conversion
13840 (_conv.func_) is used in place of A for type deduction;
13843 --If A is a cv-qualified type, the top level
13844 cv-qualifiers of A's type are ignored for type
13846 if (TREE_CODE (*arg) == ARRAY_TYPE)
13847 *arg = build_pointer_type (TREE_TYPE (*arg));
13848 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13849 *arg = build_pointer_type (*arg);
13851 *arg = TYPE_MAIN_VARIANT (*arg);
13854 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13855 of the form T&&, where T is a template parameter, and the argument
13856 is an lvalue, T is deduced as A& */
13857 if (TREE_CODE (*parm) == REFERENCE_TYPE
13858 && TYPE_REF_IS_RVALUE (*parm)
13859 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13860 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13861 && arg_expr && real_lvalue_p (arg_expr))
13862 *arg = build_reference_type (*arg);
13864 /* [temp.deduct.call]
13866 If P is a cv-qualified type, the top level cv-qualifiers
13867 of P's type are ignored for type deduction. If P is a
13868 reference type, the type referred to by P is used for
13870 *parm = TYPE_MAIN_VARIANT (*parm);
13871 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13873 *parm = TREE_TYPE (*parm);
13874 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13877 /* DR 322. For conversion deduction, remove a reference type on parm
13878 too (which has been swapped into ARG). */
13879 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13880 *arg = TREE_TYPE (*arg);
13885 /* Most parms like fn_type_unification.
13887 If SUBR is 1, we're being called recursively (to unify the
13888 arguments of a function or method parameter of a function
13892 type_unification_real (tree tparms,
13896 unsigned int xnargs,
13898 unification_kind_t strict,
13901 tree parm, arg, arg_expr;
13903 int ntparms = TREE_VEC_LENGTH (tparms);
13905 int saw_undeduced = 0;
13908 unsigned int nargs;
13911 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13912 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13913 gcc_assert (ntparms > 0);
13915 /* Reset the number of non-defaulted template arguments contained
13917 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
13922 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13923 | UNIFY_ALLOW_DERIVED);
13927 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13931 sub_strict = UNIFY_ALLOW_NONE;
13935 gcc_unreachable ();
13944 while (parms && parms != void_list_node
13947 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13950 parm = TREE_VALUE (parms);
13951 parms = TREE_CHAIN (parms);
13956 if (arg == error_mark_node)
13958 if (arg == unknown_type_node)
13959 /* We can't deduce anything from this, but we might get all the
13960 template args from other function args. */
13963 /* Conversions will be performed on a function argument that
13964 corresponds with a function parameter that contains only
13965 non-deducible template parameters and explicitly specified
13966 template parameters. */
13967 if (!uses_template_parms (parm))
13972 type = TREE_TYPE (arg);
13976 if (same_type_p (parm, type))
13978 if (strict != DEDUCE_EXACT
13979 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13988 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13989 if (type_unknown_p (arg))
13991 /* [temp.deduct.type]
13993 A template-argument can be deduced from a pointer to
13994 function or pointer to member function argument if
13995 the set of overloaded functions does not contain
13996 function templates and at most one of a set of
13997 overloaded functions provides a unique match. */
13998 if (resolve_overloaded_unification
13999 (tparms, targs, parm, arg, strict, sub_strict))
14005 arg = unlowered_expr_type (arg);
14006 if (arg == error_mark_node)
14011 int arg_strict = sub_strict;
14014 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14017 if (arg == init_list_type_node && arg_expr)
14019 if (unify (tparms, targs, parm, arg, arg_strict))
14026 && parms != void_list_node
14027 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14029 /* Unify the remaining arguments with the pack expansion type. */
14031 tree parmvec = make_tree_vec (1);
14033 /* Allocate a TREE_VEC and copy in all of the arguments */
14034 argvec = make_tree_vec (nargs - ia);
14035 for (i = 0; ia < nargs; ++ia, ++i)
14036 TREE_VEC_ELT (argvec, i) = args[ia];
14038 /* Copy the parameter into parmvec. */
14039 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14040 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14041 /*call_args_p=*/true, /*subr=*/subr))
14044 /* Advance to the end of the list of parameters. */
14045 parms = TREE_CHAIN (parms);
14048 /* Fail if we've reached the end of the parm list, and more args
14049 are present, and the parm list isn't variadic. */
14050 if (ia < nargs && parms == void_list_node)
14052 /* Fail if parms are left and they don't have default values. */
14053 if (parms && parms != void_list_node
14054 && TREE_PURPOSE (parms) == NULL_TREE)
14058 for (i = 0; i < ntparms; i++)
14059 if (!TREE_VEC_ELT (targs, i))
14063 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
14066 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14068 /* If this is an undeduced nontype parameter that depends on
14069 a type parameter, try another pass; its type may have been
14070 deduced from a later argument than the one from which
14071 this parameter can be deduced. */
14072 if (TREE_CODE (tparm) == PARM_DECL
14073 && uses_template_parms (TREE_TYPE (tparm))
14074 && !saw_undeduced++)
14077 /* Core issue #226 (C++0x) [temp.deduct]:
14079 If a template argument has not been deduced, its
14080 default template argument, if any, is used.
14082 When we are in C++98 mode, TREE_PURPOSE will either
14083 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14084 to explicitly check cxx_dialect here. */
14085 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14087 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14088 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14089 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14090 arg = convert_template_argument (parm, arg, targs, tf_none,
14092 if (arg == error_mark_node)
14096 TREE_VEC_ELT (targs, i) = arg;
14097 /* The position of the first default template argument,
14098 is also the number of non-defaulted arguments in TARGS.
14100 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14101 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14106 /* If the type parameter is a parameter pack, then it will
14107 be deduced to an empty parameter pack. */
14108 if (template_parameter_pack_p (tparm))
14112 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14114 arg = make_node (NONTYPE_ARGUMENT_PACK);
14115 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14116 TREE_CONSTANT (arg) = 1;
14119 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14121 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14123 TREE_VEC_ELT (targs, i) = arg;
14129 #ifdef ENABLE_CHECKING
14130 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14131 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14137 /* Subroutine of type_unification_real. Args are like the variables
14138 at the call site. ARG is an overloaded function (or template-id);
14139 we try deducing template args from each of the overloads, and if
14140 only one succeeds, we go with that. Modifies TARGS and returns
14141 true on success. */
14144 resolve_overloaded_unification (tree tparms,
14148 unification_kind_t strict,
14151 tree tempargs = copy_node (targs);
14153 tree goodfn = NULL_TREE;
14156 if (TREE_CODE (arg) == ADDR_EXPR)
14158 arg = TREE_OPERAND (arg, 0);
14164 if (TREE_CODE (arg) == COMPONENT_REF)
14165 /* Handle `&x' where `x' is some static or non-static member
14167 arg = TREE_OPERAND (arg, 1);
14169 if (TREE_CODE (arg) == OFFSET_REF)
14170 arg = TREE_OPERAND (arg, 1);
14172 /* Strip baselink information. */
14173 if (BASELINK_P (arg))
14174 arg = BASELINK_FUNCTIONS (arg);
14176 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14178 /* If we got some explicit template args, we need to plug them into
14179 the affected templates before we try to unify, in case the
14180 explicit args will completely resolve the templates in question. */
14182 tree expl_subargs = TREE_OPERAND (arg, 1);
14183 arg = TREE_OPERAND (arg, 0);
14185 for (; arg; arg = OVL_NEXT (arg))
14187 tree fn = OVL_CURRENT (arg);
14188 tree subargs, elem;
14190 if (TREE_CODE (fn) != TEMPLATE_DECL)
14193 ++processing_template_decl;
14194 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14195 expl_subargs, /*check_ret=*/false);
14198 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14199 if (try_one_overload (tparms, targs, tempargs, parm,
14200 elem, strict, sub_strict, addr_p)
14201 && (!goodfn || !decls_match (goodfn, elem)))
14207 --processing_template_decl;
14210 else if (TREE_CODE (arg) != OVERLOAD
14211 && TREE_CODE (arg) != FUNCTION_DECL)
14212 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14213 -- but the deduction does not succeed because the expression is
14214 not just the function on its own. */
14217 for (; arg; arg = OVL_NEXT (arg))
14218 if (try_one_overload (tparms, targs, tempargs, parm,
14219 TREE_TYPE (OVL_CURRENT (arg)),
14220 strict, sub_strict, addr_p)
14221 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
14223 goodfn = OVL_CURRENT (arg);
14227 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14228 to function or pointer to member function argument if the set of
14229 overloaded functions does not contain function templates and at most
14230 one of a set of overloaded functions provides a unique match.
14232 So if we found multiple possibilities, we return success but don't
14233 deduce anything. */
14237 int i = TREE_VEC_LENGTH (targs);
14239 if (TREE_VEC_ELT (tempargs, i))
14240 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
14248 /* Core DR 115: In contexts where deduction is done and fails, or in
14249 contexts where deduction is not done, if a template argument list is
14250 specified and it, along with any default template arguments, identifies
14251 a single function template specialization, then the template-id is an
14252 lvalue for the function template specialization. */
14255 resolve_nondeduced_context (tree orig_expr)
14257 tree expr, offset, baselink;
14260 if (!type_unknown_p (orig_expr))
14265 offset = NULL_TREE;
14266 baselink = NULL_TREE;
14268 if (TREE_CODE (expr) == ADDR_EXPR)
14270 expr = TREE_OPERAND (expr, 0);
14273 if (TREE_CODE (expr) == OFFSET_REF)
14276 expr = TREE_OPERAND (expr, 1);
14278 if (TREE_CODE (expr) == BASELINK)
14281 expr = BASELINK_FUNCTIONS (expr);
14284 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
14287 tree goodfn = NULL_TREE;
14289 /* If we got some explicit template args, we need to plug them into
14290 the affected templates before we try to unify, in case the
14291 explicit args will completely resolve the templates in question. */
14293 tree expl_subargs = TREE_OPERAND (expr, 1);
14294 tree arg = TREE_OPERAND (expr, 0);
14295 tree badfn = NULL_TREE;
14296 tree badargs = NULL_TREE;
14298 for (; arg; arg = OVL_NEXT (arg))
14300 tree fn = OVL_CURRENT (arg);
14301 tree subargs, elem;
14303 if (TREE_CODE (fn) != TEMPLATE_DECL)
14306 ++processing_template_decl;
14307 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14308 expl_subargs, /*check_ret=*/false);
14309 if (subargs && !any_dependent_template_arguments_p (subargs))
14311 elem = instantiate_template (fn, subargs, tf_none);
14312 if (elem == error_mark_node)
14317 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
14323 --processing_template_decl;
14329 expr = build_baselink (BASELINK_BINFO (baselink),
14330 BASELINK_ACCESS_BINFO (baselink),
14331 expr, BASELINK_OPTYPE (baselink));
14333 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
14334 TREE_OPERAND (offset, 0), expr);
14336 expr = build_address (expr);
14339 else if (good == 0 && badargs)
14340 /* There were no good options and at least one bad one, so let the
14341 user know what the problem is. */
14342 instantiate_template (badfn, badargs, tf_warning_or_error);
14347 /* Subroutine of resolve_overloaded_unification; does deduction for a single
14348 overload. Fills TARGS with any deduced arguments, or error_mark_node if
14349 different overloads deduce different arguments for a given parm.
14350 ADDR_P is true if the expression for which deduction is being
14351 performed was of the form "& fn" rather than simply "fn".
14353 Returns 1 on success. */
14356 try_one_overload (tree tparms,
14361 unification_kind_t strict,
14369 /* [temp.deduct.type] A template-argument can be deduced from a pointer
14370 to function or pointer to member function argument if the set of
14371 overloaded functions does not contain function templates and at most
14372 one of a set of overloaded functions provides a unique match.
14374 So if this is a template, just return success. */
14376 if (uses_template_parms (arg))
14379 if (TREE_CODE (arg) == METHOD_TYPE)
14380 arg = build_ptrmemfunc_type (build_pointer_type (arg));
14382 arg = build_pointer_type (arg);
14384 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
14386 /* We don't copy orig_targs for this because if we have already deduced
14387 some template args from previous args, unify would complain when we
14388 try to deduce a template parameter for the same argument, even though
14389 there isn't really a conflict. */
14390 nargs = TREE_VEC_LENGTH (targs);
14391 tempargs = make_tree_vec (nargs);
14393 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
14396 /* First make sure we didn't deduce anything that conflicts with
14397 explicitly specified args. */
14398 for (i = nargs; i--; )
14400 tree elt = TREE_VEC_ELT (tempargs, i);
14401 tree oldelt = TREE_VEC_ELT (orig_targs, i);
14405 else if (uses_template_parms (elt))
14406 /* Since we're unifying against ourselves, we will fill in
14407 template args used in the function parm list with our own
14408 template parms. Discard them. */
14409 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
14410 else if (oldelt && !template_args_equal (oldelt, elt))
14414 for (i = nargs; i--; )
14416 tree elt = TREE_VEC_ELT (tempargs, i);
14419 TREE_VEC_ELT (targs, i) = elt;
14425 /* PARM is a template class (perhaps with unbound template
14426 parameters). ARG is a fully instantiated type. If ARG can be
14427 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
14428 TARGS are as for unify. */
14431 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
14433 tree copy_of_targs;
14435 if (!CLASSTYPE_TEMPLATE_INFO (arg)
14436 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
14437 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
14440 /* We need to make a new template argument vector for the call to
14441 unify. If we used TARGS, we'd clutter it up with the result of
14442 the attempted unification, even if this class didn't work out.
14443 We also don't want to commit ourselves to all the unifications
14444 we've already done, since unification is supposed to be done on
14445 an argument-by-argument basis. In other words, consider the
14446 following pathological case:
14448 template <int I, int J, int K>
14451 template <int I, int J>
14452 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
14454 template <int I, int J, int K>
14455 void f(S<I, J, K>, S<I, I, I>);
14464 Now, by the time we consider the unification involving `s2', we
14465 already know that we must have `f<0, 0, 0>'. But, even though
14466 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
14467 because there are two ways to unify base classes of S<0, 1, 2>
14468 with S<I, I, I>. If we kept the already deduced knowledge, we
14469 would reject the possibility I=1. */
14470 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
14472 /* If unification failed, we're done. */
14473 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
14474 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
14480 /* Given a template type PARM and a class type ARG, find the unique
14481 base type in ARG that is an instance of PARM. We do not examine
14482 ARG itself; only its base-classes. If there is not exactly one
14483 appropriate base class, return NULL_TREE. PARM may be the type of
14484 a partial specialization, as well as a plain template type. Used
14488 get_template_base (tree tparms, tree targs, tree parm, tree arg)
14490 tree rval = NULL_TREE;
14493 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
14495 binfo = TYPE_BINFO (complete_type (arg));
14497 /* The type could not be completed. */
14500 /* Walk in inheritance graph order. The search order is not
14501 important, and this avoids multiple walks of virtual bases. */
14502 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
14504 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
14508 /* If there is more than one satisfactory baseclass, then:
14512 If they yield more than one possible deduced A, the type
14516 if (rval && !same_type_p (r, rval))
14526 /* Returns the level of DECL, which declares a template parameter. */
14529 template_decl_level (tree decl)
14531 switch (TREE_CODE (decl))
14534 case TEMPLATE_DECL:
14535 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14538 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14541 gcc_unreachable ();
14546 /* Decide whether ARG can be unified with PARM, considering only the
14547 cv-qualifiers of each type, given STRICT as documented for unify.
14548 Returns nonzero iff the unification is OK on that basis. */
14551 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14553 int arg_quals = cp_type_quals (arg);
14554 int parm_quals = cp_type_quals (parm);
14556 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14557 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14559 /* Although a CVR qualifier is ignored when being applied to a
14560 substituted template parameter ([8.3.2]/1 for example), that
14561 does not allow us to unify "const T" with "int&" because both
14562 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
14563 It is ok when we're allowing additional CV qualifiers
14564 at the outer level [14.8.2.1]/3,1st bullet. */
14565 if ((TREE_CODE (arg) == REFERENCE_TYPE
14566 || TREE_CODE (arg) == FUNCTION_TYPE
14567 || TREE_CODE (arg) == METHOD_TYPE)
14568 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14571 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14572 && (parm_quals & TYPE_QUAL_RESTRICT))
14576 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14577 && (arg_quals & parm_quals) != parm_quals)
14580 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14581 && (parm_quals & arg_quals) != arg_quals)
14587 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14589 template_parm_level_and_index (tree parm, int* level, int* index)
14591 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14592 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14593 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14595 *index = TEMPLATE_TYPE_IDX (parm);
14596 *level = TEMPLATE_TYPE_LEVEL (parm);
14600 *index = TEMPLATE_PARM_IDX (parm);
14601 *level = TEMPLATE_PARM_LEVEL (parm);
14605 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14606 expansion at the end of PACKED_PARMS. Returns 0 if the type
14607 deduction succeeds, 1 otherwise. STRICT is the same as in
14608 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14609 call argument list. We'll need to adjust the arguments to make them
14610 types. SUBR tells us if this is from a recursive call to
14611 type_unification_real. */
14613 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14614 tree packed_args, int strict, bool call_args_p,
14618 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14619 tree pattern = PACK_EXPANSION_PATTERN (parm);
14620 tree pack, packs = NULL_TREE;
14621 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14622 int len = TREE_VEC_LENGTH (packed_args);
14624 /* Determine the parameter packs we will be deducing from the
14625 pattern, and record their current deductions. */
14626 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14627 pack; pack = TREE_CHAIN (pack))
14629 tree parm_pack = TREE_VALUE (pack);
14632 /* Determine the index and level of this parameter pack. */
14633 template_parm_level_and_index (parm_pack, &level, &idx);
14635 /* Keep track of the parameter packs and their corresponding
14637 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14638 TREE_TYPE (packs) = make_tree_vec (len - start);
14641 /* Loop through all of the arguments that have not yet been
14642 unified and unify each with the pattern. */
14643 for (i = start; i < len; i++)
14645 tree parm = pattern;
14647 /* For each parameter pack, clear out the deduced value so that
14648 we can deduce it again. */
14649 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14652 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14654 TMPL_ARG (targs, level, idx) = NULL_TREE;
14657 /* Unify the pattern with the current argument. */
14659 tree arg = TREE_VEC_ELT (packed_args, i);
14660 tree arg_expr = NULL_TREE;
14661 int arg_strict = strict;
14662 bool skip_arg_p = false;
14668 /* This mirrors what we do in type_unification_real. */
14672 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14673 | UNIFY_ALLOW_MORE_CV_QUAL
14674 | UNIFY_ALLOW_DERIVED);
14678 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14682 sub_strict = UNIFY_ALLOW_NONE;
14686 gcc_unreachable ();
14691 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14692 if (type_unknown_p (arg))
14694 /* [temp.deduct.type] A template-argument can be
14695 deduced from a pointer to function or pointer
14696 to member function argument if the set of
14697 overloaded functions does not contain function
14698 templates and at most one of a set of
14699 overloaded functions provides a unique
14702 if (resolve_overloaded_unification
14703 (tparms, targs, parm, arg,
14704 (unification_kind_t) strict,
14714 arg = unlowered_expr_type (arg);
14715 if (arg == error_mark_node)
14720 arg_strict = sub_strict;
14724 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
14725 &parm, &arg, arg_expr);
14730 /* For deduction from an init-list we need the actual list. */
14731 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14733 if (unify (tparms, targs, parm, arg, arg_strict))
14738 /* For each parameter pack, collect the deduced value. */
14739 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14742 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14744 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
14745 TMPL_ARG (targs, level, idx);
14749 /* Verify that the results of unification with the parameter packs
14750 produce results consistent with what we've seen before, and make
14751 the deduced argument packs available. */
14752 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14754 tree old_pack = TREE_VALUE (pack);
14755 tree new_args = TREE_TYPE (pack);
14756 int i, len = TREE_VEC_LENGTH (new_args);
14758 bool nondeduced_p = false;
14760 /* By default keep the original deduced argument pack.
14761 If necessary, more specific code is going to update the
14762 resulting deduced argument later down in this function. */
14763 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14764 TMPL_ARG (targs, level, idx) = old_pack;
14766 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
14767 actually deduce anything. */
14768 for (i = 0; i < len && !nondeduced_p; ++i)
14769 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
14770 nondeduced_p = true;
14774 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
14776 /* Prepend the explicit arguments onto NEW_ARGS. */
14777 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14778 tree old_args = new_args;
14779 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
14780 int len = explicit_len + TREE_VEC_LENGTH (old_args);
14782 /* Copy the explicit arguments. */
14783 new_args = make_tree_vec (len);
14784 for (i = 0; i < explicit_len; i++)
14785 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
14787 /* Copy the deduced arguments. */
14788 for (; i < len; i++)
14789 TREE_VEC_ELT (new_args, i) =
14790 TREE_VEC_ELT (old_args, i - explicit_len);
14796 /* Build the deduced *_ARGUMENT_PACK. */
14797 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
14799 result = make_node (NONTYPE_ARGUMENT_PACK);
14800 TREE_TYPE (result) =
14801 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
14802 TREE_CONSTANT (result) = 1;
14805 result = cxx_make_type (TYPE_ARGUMENT_PACK);
14807 SET_ARGUMENT_PACK_ARGS (result, new_args);
14809 /* Note the deduced argument packs for this parameter
14811 TMPL_ARG (targs, level, idx) = result;
14813 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
14814 && (ARGUMENT_PACK_ARGS (old_pack)
14815 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
14817 /* We only had the explicitly-provided arguments before, but
14818 now we have a complete set of arguments. */
14819 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14821 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
14822 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
14823 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
14825 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
14827 /* Inconsistent unification of this parameter pack. */
14834 /* Deduce the value of template parameters. TPARMS is the (innermost)
14835 set of template parameters to a template. TARGS is the bindings
14836 for those template parameters, as determined thus far; TARGS may
14837 include template arguments for outer levels of template parameters
14838 as well. PARM is a parameter to a template function, or a
14839 subcomponent of that parameter; ARG is the corresponding argument.
14840 This function attempts to match PARM with ARG in a manner
14841 consistent with the existing assignments in TARGS. If more values
14842 are deduced, then TARGS is updated.
14844 Returns 0 if the type deduction succeeds, 1 otherwise. The
14845 parameter STRICT is a bitwise or of the following flags:
14848 Require an exact match between PARM and ARG.
14849 UNIFY_ALLOW_MORE_CV_QUAL:
14850 Allow the deduced ARG to be more cv-qualified (by qualification
14851 conversion) than ARG.
14852 UNIFY_ALLOW_LESS_CV_QUAL:
14853 Allow the deduced ARG to be less cv-qualified than ARG.
14854 UNIFY_ALLOW_DERIVED:
14855 Allow the deduced ARG to be a template base class of ARG,
14856 or a pointer to a template base class of the type pointed to by
14858 UNIFY_ALLOW_INTEGER:
14859 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14860 case for more information.
14861 UNIFY_ALLOW_OUTER_LEVEL:
14862 This is the outermost level of a deduction. Used to determine validity
14863 of qualification conversions. A valid qualification conversion must
14864 have const qualified pointers leading up to the inner type which
14865 requires additional CV quals, except at the outer level, where const
14866 is not required [conv.qual]. It would be normal to set this flag in
14867 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14868 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14869 This is the outermost level of a deduction, and PARM can be more CV
14870 qualified at this point.
14871 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14872 This is the outermost level of a deduction, and PARM can be less CV
14873 qualified at this point. */
14876 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14881 int strict_in = strict;
14883 /* I don't think this will do the right thing with respect to types.
14884 But the only case I've seen it in so far has been array bounds, where
14885 signedness is the only information lost, and I think that will be
14887 while (TREE_CODE (parm) == NOP_EXPR)
14888 parm = TREE_OPERAND (parm, 0);
14890 if (arg == error_mark_node)
14892 if (arg == unknown_type_node
14893 || arg == init_list_type_node)
14894 /* We can't deduce anything from this, but we might get all the
14895 template args from other function args. */
14898 /* If PARM uses template parameters, then we can't bail out here,
14899 even if ARG == PARM, since we won't record unifications for the
14900 template parameters. We might need them if we're trying to
14901 figure out which of two things is more specialized. */
14902 if (arg == parm && !uses_template_parms (parm))
14905 /* Handle init lists early, so the rest of the function can assume
14906 we're dealing with a type. */
14907 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14911 tree orig_parm = parm;
14913 /* Replace T with std::initializer_list<T> for deduction. */
14914 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14915 && flag_deduce_init_list)
14916 parm = listify (parm);
14918 if (!is_std_init_list (parm))
14919 /* We can only deduce from an initializer list argument if the
14920 parameter is std::initializer_list; otherwise this is a
14921 non-deduced context. */
14924 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14926 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14928 int elt_strict = strict;
14930 if (elt == error_mark_node)
14933 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14935 tree type = TREE_TYPE (elt);
14936 /* It should only be possible to get here for a call. */
14937 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14938 elt_strict |= maybe_adjust_types_for_deduction
14939 (DEDUCE_CALL, &elttype, &type, elt);
14943 if (unify (tparms, targs, elttype, elt, elt_strict))
14947 /* If the std::initializer_list<T> deduction worked, replace the
14948 deduced A with std::initializer_list<A>. */
14949 if (orig_parm != parm)
14951 idx = TEMPLATE_TYPE_IDX (orig_parm);
14952 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14953 targ = listify (targ);
14954 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14959 /* Immediately reject some pairs that won't unify because of
14960 cv-qualification mismatches. */
14961 if (TREE_CODE (arg) == TREE_CODE (parm)
14963 /* It is the elements of the array which hold the cv quals of an array
14964 type, and the elements might be template type parms. We'll check
14965 when we recurse. */
14966 && TREE_CODE (arg) != ARRAY_TYPE
14967 /* We check the cv-qualifiers when unifying with template type
14968 parameters below. We want to allow ARG `const T' to unify with
14969 PARM `T' for example, when computing which of two templates
14970 is more specialized, for example. */
14971 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14972 && !check_cv_quals_for_unify (strict_in, arg, parm))
14975 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14976 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14977 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14978 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14979 strict &= ~UNIFY_ALLOW_DERIVED;
14980 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14981 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14983 switch (TREE_CODE (parm))
14985 case TYPENAME_TYPE:
14987 case UNBOUND_CLASS_TEMPLATE:
14988 /* In a type which contains a nested-name-specifier, template
14989 argument values cannot be deduced for template parameters used
14990 within the nested-name-specifier. */
14993 case TEMPLATE_TYPE_PARM:
14994 case TEMPLATE_TEMPLATE_PARM:
14995 case BOUND_TEMPLATE_TEMPLATE_PARM:
14996 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14997 if (tparm == error_mark_node)
15000 if (TEMPLATE_TYPE_LEVEL (parm)
15001 != template_decl_level (tparm))
15002 /* The PARM is not one we're trying to unify. Just check
15003 to see if it matches ARG. */
15004 return (TREE_CODE (arg) == TREE_CODE (parm)
15005 && same_type_p (parm, arg)) ? 0 : 1;
15006 idx = TEMPLATE_TYPE_IDX (parm);
15007 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15008 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15010 /* Check for mixed types and values. */
15011 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15012 && TREE_CODE (tparm) != TYPE_DECL)
15013 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15014 && TREE_CODE (tparm) != TEMPLATE_DECL))
15017 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15019 /* ARG must be constructed from a template class or a template
15020 template parameter. */
15021 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15022 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15026 tree parmvec = TYPE_TI_ARGS (parm);
15027 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15028 tree full_argvec = add_to_template_args (targs, argvec);
15030 = DECL_INNERMOST_TEMPLATE_PARMS
15031 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15033 int parm_variadic_p = 0;
15035 /* The resolution to DR150 makes clear that default
15036 arguments for an N-argument may not be used to bind T
15037 to a template template parameter with fewer than N
15038 parameters. It is not safe to permit the binding of
15039 default arguments as an extension, as that may change
15040 the meaning of a conforming program. Consider:
15042 struct Dense { static const unsigned int dim = 1; };
15044 template <template <typename> class View,
15046 void operator+(float, View<Block> const&);
15048 template <typename Block,
15049 unsigned int Dim = Block::dim>
15050 struct Lvalue_proxy { operator float() const; };
15054 Lvalue_proxy<Dense> p;
15059 Here, if Lvalue_proxy is permitted to bind to View, then
15060 the global operator+ will be used; if they are not, the
15061 Lvalue_proxy will be converted to float. */
15062 if (coerce_template_parms (parm_parms,
15064 TYPE_TI_TEMPLATE (parm),
15066 /*require_all_args=*/true,
15067 /*use_default_args=*/false)
15068 == error_mark_node)
15071 /* Deduce arguments T, i from TT<T> or TT<i>.
15072 We check each element of PARMVEC and ARGVEC individually
15073 rather than the whole TREE_VEC since they can have
15074 different number of elements. */
15076 parmvec = expand_template_argument_pack (parmvec);
15077 argvec = expand_template_argument_pack (argvec);
15079 len = TREE_VEC_LENGTH (parmvec);
15081 /* Check if the parameters end in a pack, making them
15084 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15085 parm_variadic_p = 1;
15087 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15090 for (i = 0; i < len - parm_variadic_p; ++i)
15092 if (unify (tparms, targs,
15093 TREE_VEC_ELT (parmvec, i),
15094 TREE_VEC_ELT (argvec, i),
15099 if (parm_variadic_p
15100 && unify_pack_expansion (tparms, targs,
15103 /*call_args_p=*/false,
15107 arg = TYPE_TI_TEMPLATE (arg);
15109 /* Fall through to deduce template name. */
15112 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15113 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15115 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15117 /* Simple cases: Value already set, does match or doesn't. */
15118 if (targ != NULL_TREE && template_args_equal (targ, arg))
15125 /* If PARM is `const T' and ARG is only `int', we don't have
15126 a match unless we are allowing additional qualification.
15127 If ARG is `const int' and PARM is just `T' that's OK;
15128 that binds `const int' to `T'. */
15129 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15133 /* Consider the case where ARG is `const volatile int' and
15134 PARM is `const T'. Then, T should be `volatile int'. */
15135 arg = cp_build_qualified_type_real
15136 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15137 if (arg == error_mark_node)
15140 /* Simple cases: Value already set, does match or doesn't. */
15141 if (targ != NULL_TREE && same_type_p (targ, arg))
15146 /* Make sure that ARG is not a variable-sized array. (Note
15147 that were talking about variable-sized arrays (like
15148 `int[n]'), rather than arrays of unknown size (like
15149 `int[]').) We'll get very confused by such a type since
15150 the bound of the array will not be computable in an
15151 instantiation. Besides, such types are not allowed in
15152 ISO C++, so we can do as we please here. */
15153 if (variably_modified_type_p (arg, NULL_TREE))
15156 /* Strip typedefs as in convert_template_argument. */
15157 arg = strip_typedefs (arg);
15160 /* If ARG is a parameter pack or an expansion, we cannot unify
15161 against it unless PARM is also a parameter pack. */
15162 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15163 && !template_parameter_pack_p (parm))
15166 /* If the argument deduction results is a METHOD_TYPE,
15167 then there is a problem.
15168 METHOD_TYPE doesn't map to any real C++ type the result of
15169 the deduction can not be of that type. */
15170 if (TREE_CODE (arg) == METHOD_TYPE)
15173 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15176 case TEMPLATE_PARM_INDEX:
15177 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15178 if (tparm == error_mark_node)
15181 if (TEMPLATE_PARM_LEVEL (parm)
15182 != template_decl_level (tparm))
15183 /* The PARM is not one we're trying to unify. Just check
15184 to see if it matches ARG. */
15185 return !(TREE_CODE (arg) == TREE_CODE (parm)
15186 && cp_tree_equal (parm, arg));
15188 idx = TEMPLATE_PARM_IDX (parm);
15189 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15192 return !cp_tree_equal (targ, arg);
15194 /* [temp.deduct.type] If, in the declaration of a function template
15195 with a non-type template-parameter, the non-type
15196 template-parameter is used in an expression in the function
15197 parameter-list and, if the corresponding template-argument is
15198 deduced, the template-argument type shall match the type of the
15199 template-parameter exactly, except that a template-argument
15200 deduced from an array bound may be of any integral type.
15201 The non-type parameter might use already deduced type parameters. */
15202 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
15203 if (!TREE_TYPE (arg))
15204 /* Template-parameter dependent expression. Just accept it for now.
15205 It will later be processed in convert_template_argument. */
15207 else if (same_type_p (TREE_TYPE (arg), tparm))
15209 else if ((strict & UNIFY_ALLOW_INTEGER)
15210 && (TREE_CODE (tparm) == INTEGER_TYPE
15211 || TREE_CODE (tparm) == BOOLEAN_TYPE))
15212 /* Convert the ARG to the type of PARM; the deduced non-type
15213 template argument must exactly match the types of the
15214 corresponding parameter. */
15215 arg = fold (build_nop (tparm, arg));
15216 else if (uses_template_parms (tparm))
15217 /* We haven't deduced the type of this parameter yet. Try again
15223 /* If ARG is a parameter pack or an expansion, we cannot unify
15224 against it unless PARM is also a parameter pack. */
15225 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15226 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
15229 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15234 /* A pointer-to-member constant can be unified only with
15235 another constant. */
15236 if (TREE_CODE (arg) != PTRMEM_CST)
15239 /* Just unify the class member. It would be useless (and possibly
15240 wrong, depending on the strict flags) to unify also
15241 PTRMEM_CST_CLASS, because we want to be sure that both parm and
15242 arg refer to the same variable, even if through different
15243 classes. For instance:
15245 struct A { int x; };
15248 Unification of &A::x and &B::x must succeed. */
15249 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
15250 PTRMEM_CST_MEMBER (arg), strict);
15255 if (TREE_CODE (arg) != POINTER_TYPE)
15258 /* [temp.deduct.call]
15260 A can be another pointer or pointer to member type that can
15261 be converted to the deduced A via a qualification
15262 conversion (_conv.qual_).
15264 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
15265 This will allow for additional cv-qualification of the
15266 pointed-to types if appropriate. */
15268 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
15269 /* The derived-to-base conversion only persists through one
15270 level of pointers. */
15271 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
15273 return unify (tparms, targs, TREE_TYPE (parm),
15274 TREE_TYPE (arg), strict);
15277 case REFERENCE_TYPE:
15278 if (TREE_CODE (arg) != REFERENCE_TYPE)
15280 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15281 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15284 if (TREE_CODE (arg) != ARRAY_TYPE)
15286 if ((TYPE_DOMAIN (parm) == NULL_TREE)
15287 != (TYPE_DOMAIN (arg) == NULL_TREE))
15289 if (TYPE_DOMAIN (parm) != NULL_TREE)
15296 /* Our representation of array types uses "N - 1" as the
15297 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
15298 not an integer constant. We cannot unify arbitrarily
15299 complex expressions, so we eliminate the MINUS_EXPRs
15301 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
15302 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
15305 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
15306 parm_max = TREE_OPERAND (parm_max, 0);
15308 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
15309 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
15312 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
15313 trying to unify the type of a variable with the type
15314 of a template parameter. For example:
15316 template <unsigned int N>
15317 void f (char (&) [N]);
15324 Here, the type of the ARG will be "int [g(i)]", and
15325 may be a SAVE_EXPR, etc. */
15326 if (TREE_CODE (arg_max) != MINUS_EXPR)
15328 arg_max = TREE_OPERAND (arg_max, 0);
15331 /* If only one of the bounds used a MINUS_EXPR, compensate
15332 by adding one to the other bound. */
15333 if (parm_cst && !arg_cst)
15334 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
15338 else if (arg_cst && !parm_cst)
15339 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
15344 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
15347 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15348 strict & UNIFY_ALLOW_MORE_CV_QUAL);
15355 case ENUMERAL_TYPE:
15357 if (TREE_CODE (arg) != TREE_CODE (parm))
15360 /* We have already checked cv-qualification at the top of the
15362 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
15365 /* As far as unification is concerned, this wins. Later checks
15366 will invalidate it if necessary. */
15369 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
15370 /* Type INTEGER_CST can come from ordinary constant template args. */
15372 while (TREE_CODE (arg) == NOP_EXPR)
15373 arg = TREE_OPERAND (arg, 0);
15375 if (TREE_CODE (arg) != INTEGER_CST)
15377 return !tree_int_cst_equal (parm, arg);
15382 if (TREE_CODE (arg) != TREE_VEC)
15384 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
15386 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
15387 if (unify (tparms, targs,
15388 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
15396 if (TREE_CODE (arg) != TREE_CODE (parm))
15399 if (TYPE_PTRMEMFUNC_P (parm))
15401 if (!TYPE_PTRMEMFUNC_P (arg))
15404 return unify (tparms, targs,
15405 TYPE_PTRMEMFUNC_FN_TYPE (parm),
15406 TYPE_PTRMEMFUNC_FN_TYPE (arg),
15410 if (CLASSTYPE_TEMPLATE_INFO (parm))
15412 tree t = NULL_TREE;
15414 if (strict_in & UNIFY_ALLOW_DERIVED)
15416 /* First, we try to unify the PARM and ARG directly. */
15417 t = try_class_unification (tparms, targs,
15422 /* Fallback to the special case allowed in
15423 [temp.deduct.call]:
15425 If P is a class, and P has the form
15426 template-id, then A can be a derived class of
15427 the deduced A. Likewise, if P is a pointer to
15428 a class of the form template-id, A can be a
15429 pointer to a derived class pointed to by the
15431 t = get_template_base (tparms, targs, parm, arg);
15437 else if (CLASSTYPE_TEMPLATE_INFO (arg)
15438 && (CLASSTYPE_TI_TEMPLATE (parm)
15439 == CLASSTYPE_TI_TEMPLATE (arg)))
15440 /* Perhaps PARM is something like S<U> and ARG is S<int>.
15441 Then, we should unify `int' and `U'. */
15444 /* There's no chance of unification succeeding. */
15447 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
15448 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
15450 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
15455 case FUNCTION_TYPE:
15457 unsigned int nargs;
15462 if (TREE_CODE (arg) != TREE_CODE (parm))
15465 /* CV qualifications for methods can never be deduced, they must
15466 match exactly. We need to check them explicitly here,
15467 because type_unification_real treats them as any other
15468 cv-qualified parameter. */
15469 if (TREE_CODE (parm) == METHOD_TYPE
15470 && (!check_cv_quals_for_unify
15472 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
15473 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
15476 if (unify (tparms, targs, TREE_TYPE (parm),
15477 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
15480 nargs = list_length (TYPE_ARG_TYPES (arg));
15481 args = XALLOCAVEC (tree, nargs);
15482 for (a = TYPE_ARG_TYPES (arg), i = 0;
15483 a != NULL_TREE && a != void_list_node;
15484 a = TREE_CHAIN (a), ++i)
15485 args[i] = TREE_VALUE (a);
15488 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
15489 args, nargs, 1, DEDUCE_EXACT,
15494 /* Unify a pointer to member with a pointer to member function, which
15495 deduces the type of the member as a function type. */
15496 if (TYPE_PTRMEMFUNC_P (arg))
15501 /* Check top-level cv qualifiers */
15502 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
15505 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15506 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
15509 /* Determine the type of the function we are unifying against. */
15510 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
15512 build_function_type (TREE_TYPE (method_type),
15513 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15515 /* Extract the cv-qualifiers of the member function from the
15516 implicit object parameter and place them on the function
15517 type to be restored later. */
15518 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
15519 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15522 if (TREE_CODE (arg) != OFFSET_TYPE)
15524 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15525 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15527 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15531 if (DECL_TEMPLATE_PARM_P (parm))
15532 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15533 if (arg != integral_constant_value (parm))
15538 case TEMPLATE_DECL:
15539 /* Matched cases are handled by the ARG == PARM test above. */
15543 /* A non-type template parameter that is a variable should be a
15544 an integral constant, in which case, it whould have been
15545 folded into its (constant) value. So we should not be getting
15546 a variable here. */
15547 gcc_unreachable ();
15549 case TYPE_ARGUMENT_PACK:
15550 case NONTYPE_ARGUMENT_PACK:
15552 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15553 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15554 int i, len = TREE_VEC_LENGTH (packed_parms);
15555 int argslen = TREE_VEC_LENGTH (packed_args);
15556 int parm_variadic_p = 0;
15558 for (i = 0; i < len; ++i)
15560 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15563 /* We can unify against something with a trailing
15565 parm_variadic_p = 1;
15567 /* Since there is something following the pack
15568 expansion, we cannot unify this template argument
15575 /* If we don't have enough arguments to satisfy the parameters
15576 (not counting the pack expression at the end), or we have
15577 too many arguments for a parameter list that doesn't end in
15578 a pack expression, we can't unify. */
15579 if (argslen < (len - parm_variadic_p)
15580 || (argslen > len && !parm_variadic_p))
15583 /* Unify all of the parameters that precede the (optional)
15584 pack expression. */
15585 for (i = 0; i < len - parm_variadic_p; ++i)
15587 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15588 TREE_VEC_ELT (packed_args, i), strict))
15592 if (parm_variadic_p)
15593 return unify_pack_expansion (tparms, targs,
15594 packed_parms, packed_args,
15595 strict, /*call_args_p=*/false,
15603 case DECLTYPE_TYPE:
15604 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
15609 /* Unification fails if we hit an error node. */
15613 gcc_assert (EXPR_P (parm));
15615 /* We must be looking at an expression. This can happen with
15619 void foo(S<I>, S<I + 2>);
15621 This is a "nondeduced context":
15625 The nondeduced contexts are:
15627 --A type that is a template-id in which one or more of
15628 the template-arguments is an expression that references
15629 a template-parameter.
15631 In these cases, we assume deduction succeeded, but don't
15632 actually infer any unifications. */
15634 if (!uses_template_parms (parm)
15635 && !template_args_equal (parm, arg))
15642 /* Note that DECL can be defined in this translation unit, if
15646 mark_definable (tree decl)
15649 DECL_NOT_REALLY_EXTERN (decl) = 1;
15650 FOR_EACH_CLONE (clone, decl)
15651 DECL_NOT_REALLY_EXTERN (clone) = 1;
15654 /* Called if RESULT is explicitly instantiated, or is a member of an
15655 explicitly instantiated class. */
15658 mark_decl_instantiated (tree result, int extern_p)
15660 SET_DECL_EXPLICIT_INSTANTIATION (result);
15662 /* If this entity has already been written out, it's too late to
15663 make any modifications. */
15664 if (TREE_ASM_WRITTEN (result))
15667 if (TREE_CODE (result) != FUNCTION_DECL)
15668 /* The TREE_PUBLIC flag for function declarations will have been
15669 set correctly by tsubst. */
15670 TREE_PUBLIC (result) = 1;
15672 /* This might have been set by an earlier implicit instantiation. */
15673 DECL_COMDAT (result) = 0;
15676 DECL_NOT_REALLY_EXTERN (result) = 0;
15679 mark_definable (result);
15680 /* Always make artificials weak. */
15681 if (DECL_ARTIFICIAL (result) && flag_weak)
15682 comdat_linkage (result);
15683 /* For WIN32 we also want to put explicit instantiations in
15684 linkonce sections. */
15685 else if (TREE_PUBLIC (result))
15686 maybe_make_one_only (result);
15689 /* If EXTERN_P, then this function will not be emitted -- unless
15690 followed by an explicit instantiation, at which point its linkage
15691 will be adjusted. If !EXTERN_P, then this function will be
15692 emitted here. In neither circumstance do we want
15693 import_export_decl to adjust the linkage. */
15694 DECL_INTERFACE_KNOWN (result) = 1;
15697 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
15698 important template arguments. If any are missing, we check whether
15699 they're important by using error_mark_node for substituting into any
15700 args that were used for partial ordering (the ones between ARGS and END)
15701 and seeing if it bubbles up. */
15704 check_undeduced_parms (tree targs, tree args, tree end)
15706 bool found = false;
15708 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
15709 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
15712 TREE_VEC_ELT (targs, i) = error_mark_node;
15716 for (; args != end; args = TREE_CHAIN (args))
15718 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
15719 if (substed == error_mark_node)
15726 /* Given two function templates PAT1 and PAT2, return:
15728 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
15729 -1 if PAT2 is more specialized than PAT1.
15730 0 if neither is more specialized.
15732 LEN indicates the number of parameters we should consider
15733 (defaulted parameters should not be considered).
15735 The 1998 std underspecified function template partial ordering, and
15736 DR214 addresses the issue. We take pairs of arguments, one from
15737 each of the templates, and deduce them against each other. One of
15738 the templates will be more specialized if all the *other*
15739 template's arguments deduce against its arguments and at least one
15740 of its arguments *does* *not* deduce against the other template's
15741 corresponding argument. Deduction is done as for class templates.
15742 The arguments used in deduction have reference and top level cv
15743 qualifiers removed. Iff both arguments were originally reference
15744 types *and* deduction succeeds in both directions, the template
15745 with the more cv-qualified argument wins for that pairing (if
15746 neither is more cv-qualified, they both are equal). Unlike regular
15747 deduction, after all the arguments have been deduced in this way,
15748 we do *not* verify the deduced template argument values can be
15749 substituted into non-deduced contexts.
15751 The logic can be a bit confusing here, because we look at deduce1 and
15752 targs1 to see if pat2 is at least as specialized, and vice versa; if we
15753 can find template arguments for pat1 to make arg1 look like arg2, that
15754 means that arg2 is at least as specialized as arg1. */
15757 more_specialized_fn (tree pat1, tree pat2, int len)
15759 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
15760 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
15761 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
15762 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
15763 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
15764 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
15765 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
15766 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
15767 tree origs1, origs2;
15768 bool lose1 = false;
15769 bool lose2 = false;
15771 /* Remove the this parameter from non-static member functions. If
15772 one is a non-static member function and the other is not a static
15773 member function, remove the first parameter from that function
15774 also. This situation occurs for operator functions where we
15775 locate both a member function (with this pointer) and non-member
15776 operator (with explicit first operand). */
15777 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
15779 len--; /* LEN is the number of significant arguments for DECL1 */
15780 args1 = TREE_CHAIN (args1);
15781 if (!DECL_STATIC_FUNCTION_P (decl2))
15782 args2 = TREE_CHAIN (args2);
15784 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
15786 args2 = TREE_CHAIN (args2);
15787 if (!DECL_STATIC_FUNCTION_P (decl1))
15790 args1 = TREE_CHAIN (args1);
15794 /* If only one is a conversion operator, they are unordered. */
15795 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
15798 /* Consider the return type for a conversion function */
15799 if (DECL_CONV_FN_P (decl1))
15801 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
15802 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
15806 processing_template_decl++;
15812 /* Stop when an ellipsis is seen. */
15813 && args1 != NULL_TREE && args2 != NULL_TREE)
15815 tree arg1 = TREE_VALUE (args1);
15816 tree arg2 = TREE_VALUE (args2);
15817 int deduce1, deduce2;
15821 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15822 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15824 /* When both arguments are pack expansions, we need only
15825 unify the patterns themselves. */
15826 arg1 = PACK_EXPANSION_PATTERN (arg1);
15827 arg2 = PACK_EXPANSION_PATTERN (arg2);
15829 /* This is the last comparison we need to do. */
15833 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15835 arg1 = TREE_TYPE (arg1);
15836 quals1 = cp_type_quals (arg1);
15839 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15841 arg2 = TREE_TYPE (arg2);
15842 quals2 = cp_type_quals (arg2);
15845 if ((quals1 < 0) != (quals2 < 0))
15847 /* Only of the args is a reference, see if we should apply
15848 array/function pointer decay to it. This is not part of
15849 DR214, but is, IMHO, consistent with the deduction rules
15850 for the function call itself, and with our earlier
15851 implementation of the underspecified partial ordering
15852 rules. (nathan). */
15855 switch (TREE_CODE (arg1))
15858 arg1 = TREE_TYPE (arg1);
15860 case FUNCTION_TYPE:
15861 arg1 = build_pointer_type (arg1);
15870 switch (TREE_CODE (arg2))
15873 arg2 = TREE_TYPE (arg2);
15875 case FUNCTION_TYPE:
15876 arg2 = build_pointer_type (arg2);
15885 arg1 = TYPE_MAIN_VARIANT (arg1);
15886 arg2 = TYPE_MAIN_VARIANT (arg2);
15888 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15890 int i, len2 = list_length (args2);
15891 tree parmvec = make_tree_vec (1);
15892 tree argvec = make_tree_vec (len2);
15895 /* Setup the parameter vector, which contains only ARG1. */
15896 TREE_VEC_ELT (parmvec, 0) = arg1;
15898 /* Setup the argument vector, which contains the remaining
15900 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15901 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15903 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15904 argvec, UNIFY_ALLOW_NONE,
15905 /*call_args_p=*/false,
15908 /* We cannot deduce in the other direction, because ARG1 is
15909 a pack expansion but ARG2 is not. */
15912 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15914 int i, len1 = list_length (args1);
15915 tree parmvec = make_tree_vec (1);
15916 tree argvec = make_tree_vec (len1);
15919 /* Setup the parameter vector, which contains only ARG1. */
15920 TREE_VEC_ELT (parmvec, 0) = arg2;
15922 /* Setup the argument vector, which contains the remaining
15924 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15925 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15927 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15928 argvec, UNIFY_ALLOW_NONE,
15929 /*call_args_p=*/false,
15932 /* We cannot deduce in the other direction, because ARG2 is
15933 a pack expansion but ARG1 is not.*/
15939 /* The normal case, where neither argument is a pack
15941 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15942 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15945 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15946 arg2, then arg2 is not as specialized as arg1. */
15952 /* "If, for a given type, deduction succeeds in both directions
15953 (i.e., the types are identical after the transformations above)
15954 and if the type from the argument template is more cv-qualified
15955 than the type from the parameter template (as described above)
15956 that type is considered to be more specialized than the other. If
15957 neither type is more cv-qualified than the other then neither type
15958 is more specialized than the other." */
15960 if (deduce1 && deduce2
15961 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
15963 if ((quals1 & quals2) == quals2)
15965 if ((quals1 & quals2) == quals1)
15969 if (lose1 && lose2)
15970 /* We've failed to deduce something in either direction.
15971 These must be unordered. */
15974 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15975 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15976 /* We have already processed all of the arguments in our
15977 handing of the pack expansion type. */
15980 args1 = TREE_CHAIN (args1);
15981 args2 = TREE_CHAIN (args2);
15984 /* "In most cases, all template parameters must have values in order for
15985 deduction to succeed, but for partial ordering purposes a template
15986 parameter may remain without a value provided it is not used in the
15987 types being used for partial ordering."
15989 Thus, if we are missing any of the targs1 we need to substitute into
15990 origs1, then pat2 is not as specialized as pat1. This can happen when
15991 there is a nondeduced context. */
15992 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15994 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15997 processing_template_decl--;
15999 /* All things being equal, if the next argument is a pack expansion
16000 for one function but not for the other, prefer the
16001 non-variadic function. FIXME this is bogus; see c++/41958. */
16003 && args1 && TREE_VALUE (args1)
16004 && args2 && TREE_VALUE (args2))
16006 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16007 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16010 if (lose1 == lose2)
16018 /* Determine which of two partial specializations is more specialized.
16020 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16021 to the first partial specialization. The TREE_VALUE is the
16022 innermost set of template parameters for the partial
16023 specialization. PAT2 is similar, but for the second template.
16025 Return 1 if the first partial specialization is more specialized;
16026 -1 if the second is more specialized; 0 if neither is more
16029 See [temp.class.order] for information about determining which of
16030 two templates is more specialized. */
16033 more_specialized_class (tree pat1, tree pat2)
16038 bool any_deductions = false;
16040 tmpl1 = TREE_TYPE (pat1);
16041 tmpl2 = TREE_TYPE (pat2);
16043 /* Just like what happens for functions, if we are ordering between
16044 different class template specializations, we may encounter dependent
16045 types in the arguments, and we need our dependency check functions
16046 to behave correctly. */
16047 ++processing_template_decl;
16048 targs = get_class_bindings (TREE_VALUE (pat1),
16049 CLASSTYPE_TI_ARGS (tmpl1),
16050 CLASSTYPE_TI_ARGS (tmpl2));
16054 any_deductions = true;
16057 targs = get_class_bindings (TREE_VALUE (pat2),
16058 CLASSTYPE_TI_ARGS (tmpl2),
16059 CLASSTYPE_TI_ARGS (tmpl1));
16063 any_deductions = true;
16065 --processing_template_decl;
16067 /* In the case of a tie where at least one of the class templates
16068 has a parameter pack at the end, the template with the most
16069 non-packed parameters wins. */
16072 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16073 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16075 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16076 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16077 int len1 = TREE_VEC_LENGTH (args1);
16078 int len2 = TREE_VEC_LENGTH (args2);
16080 /* We don't count the pack expansion at the end. */
16081 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16083 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16088 else if (len1 < len2)
16095 /* Return the template arguments that will produce the function signature
16096 DECL from the function template FN, with the explicit template
16097 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16098 also match. Return NULL_TREE if no satisfactory arguments could be
16102 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16104 int ntparms = DECL_NTPARMS (fn);
16105 tree targs = make_tree_vec (ntparms);
16107 tree decl_arg_types;
16109 unsigned int nargs, ix;
16112 /* Substitute the explicit template arguments into the type of DECL.
16113 The call to fn_type_unification will handle substitution into the
16115 decl_type = TREE_TYPE (decl);
16116 if (explicit_args && uses_template_parms (decl_type))
16119 tree converted_args;
16121 if (DECL_TEMPLATE_INFO (decl))
16122 tmpl = DECL_TI_TEMPLATE (decl);
16124 /* We can get here for some invalid specializations. */
16128 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16129 explicit_args, NULL_TREE,
16131 /*require_all_args=*/false,
16132 /*use_default_args=*/false);
16133 if (converted_args == error_mark_node)
16136 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16137 if (decl_type == error_mark_node)
16141 /* Never do unification on the 'this' parameter. */
16142 decl_arg_types = skip_artificial_parms_for (decl,
16143 TYPE_ARG_TYPES (decl_type));
16145 nargs = list_length (decl_arg_types);
16146 args = XALLOCAVEC (tree, nargs);
16147 for (arg = decl_arg_types, ix = 0;
16148 arg != NULL_TREE && arg != void_list_node;
16149 arg = TREE_CHAIN (arg), ++ix)
16150 args[ix] = TREE_VALUE (arg);
16152 if (fn_type_unification (fn, explicit_args, targs,
16154 (check_rettype || DECL_CONV_FN_P (fn)
16155 ? TREE_TYPE (decl_type) : NULL_TREE),
16156 DEDUCE_EXACT, LOOKUP_NORMAL))
16162 /* Return the innermost template arguments that, when applied to a
16163 template specialization whose innermost template parameters are
16164 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
16167 For example, suppose we have:
16169 template <class T, class U> struct S {};
16170 template <class T> struct S<T*, int> {};
16172 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
16173 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
16174 int}. The resulting vector will be {double}, indicating that `T'
16175 is bound to `double'. */
16178 get_class_bindings (tree tparms, tree spec_args, tree args)
16180 int i, ntparms = TREE_VEC_LENGTH (tparms);
16182 tree innermost_deduced_args;
16184 innermost_deduced_args = make_tree_vec (ntparms);
16185 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16187 deduced_args = copy_node (args);
16188 SET_TMPL_ARGS_LEVEL (deduced_args,
16189 TMPL_ARGS_DEPTH (deduced_args),
16190 innermost_deduced_args);
16193 deduced_args = innermost_deduced_args;
16195 if (unify (tparms, deduced_args,
16196 INNERMOST_TEMPLATE_ARGS (spec_args),
16197 INNERMOST_TEMPLATE_ARGS (args),
16201 for (i = 0; i < ntparms; ++i)
16202 if (! TREE_VEC_ELT (innermost_deduced_args, i))
16205 /* Verify that nondeduced template arguments agree with the type
16206 obtained from argument deduction.
16210 struct A { typedef int X; };
16211 template <class T, class U> struct C {};
16212 template <class T> struct C<T, typename T::X> {};
16214 Then with the instantiation `C<A, int>', we can deduce that
16215 `T' is `A' but unify () does not check whether `typename T::X'
16217 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
16218 if (spec_args == error_mark_node
16219 /* We only need to check the innermost arguments; the other
16220 arguments will always agree. */
16221 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
16222 INNERMOST_TEMPLATE_ARGS (args)))
16225 /* Now that we have bindings for all of the template arguments,
16226 ensure that the arguments deduced for the template template
16227 parameters have compatible template parameter lists. See the use
16228 of template_template_parm_bindings_ok_p in fn_type_unification
16229 for more information. */
16230 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
16233 return deduced_args;
16236 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
16237 Return the TREE_LIST node with the most specialized template, if
16238 any. If there is no most specialized template, the error_mark_node
16241 Note that this function does not look at, or modify, the
16242 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
16243 returned is one of the elements of INSTANTIATIONS, callers may
16244 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
16245 and retrieve it from the value returned. */
16248 most_specialized_instantiation (tree templates)
16252 ++processing_template_decl;
16255 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
16259 if (get_bindings (TREE_VALUE (champ),
16260 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16261 NULL_TREE, /*check_ret=*/false))
16264 if (get_bindings (TREE_VALUE (fn),
16265 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16266 NULL_TREE, /*check_ret=*/false))
16273 /* Equally specialized, move to next function. If there
16274 is no next function, nothing's most specialized. */
16275 fn = TREE_CHAIN (fn);
16283 /* Now verify that champ is better than everything earlier in the
16284 instantiation list. */
16285 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
16286 if (get_bindings (TREE_VALUE (champ),
16287 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
16288 NULL_TREE, /*check_ret=*/false)
16289 || !get_bindings (TREE_VALUE (fn),
16290 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
16291 NULL_TREE, /*check_ret=*/false))
16297 processing_template_decl--;
16300 return error_mark_node;
16305 /* If DECL is a specialization of some template, return the most
16306 general such template. Otherwise, returns NULL_TREE.
16308 For example, given:
16310 template <class T> struct S { template <class U> void f(U); };
16312 if TMPL is `template <class U> void S<int>::f(U)' this will return
16313 the full template. This function will not trace past partial
16314 specializations, however. For example, given in addition:
16316 template <class T> struct S<T*> { template <class U> void f(U); };
16318 if TMPL is `template <class U> void S<int*>::f(U)' this will return
16319 `template <class T> template <class U> S<T*>::f(U)'. */
16322 most_general_template (tree decl)
16324 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
16325 an immediate specialization. */
16326 if (TREE_CODE (decl) == FUNCTION_DECL)
16328 if (DECL_TEMPLATE_INFO (decl)) {
16329 decl = DECL_TI_TEMPLATE (decl);
16331 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
16332 template friend. */
16333 if (TREE_CODE (decl) != TEMPLATE_DECL)
16339 /* Look for more and more general templates. */
16340 while (DECL_TEMPLATE_INFO (decl))
16342 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
16343 (See cp-tree.h for details.) */
16344 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
16347 if (CLASS_TYPE_P (TREE_TYPE (decl))
16348 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
16351 /* Stop if we run into an explicitly specialized class template. */
16352 if (!DECL_NAMESPACE_SCOPE_P (decl)
16353 && DECL_CONTEXT (decl)
16354 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
16357 decl = DECL_TI_TEMPLATE (decl);
16363 /* Return the most specialized of the class template partial
16364 specializations of TMPL which can produce TYPE, a specialization of
16365 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
16366 a _TYPE node corresponding to the partial specialization, while the
16367 TREE_PURPOSE is the set of template arguments that must be
16368 substituted into the TREE_TYPE in order to generate TYPE.
16370 If the choice of partial specialization is ambiguous, a diagnostic
16371 is issued, and the error_mark_node is returned. If there are no
16372 partial specializations of TMPL matching TYPE, then NULL_TREE is
16376 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
16378 tree list = NULL_TREE;
16384 tree outer_args = NULL_TREE;
16386 tmpl = most_general_template (tmpl);
16387 args = CLASSTYPE_TI_ARGS (type);
16389 /* For determining which partial specialization to use, only the
16390 innermost args are interesting. */
16391 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
16393 outer_args = strip_innermost_template_args (args, 1);
16394 args = INNERMOST_TEMPLATE_ARGS (args);
16397 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
16399 tree partial_spec_args;
16401 tree parms = TREE_VALUE (t);
16403 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
16405 ++processing_template_decl;
16411 /* Discard the outer levels of args, and then substitute in the
16412 template args from the enclosing class. */
16413 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
16414 partial_spec_args = tsubst_template_args
16415 (partial_spec_args, outer_args, tf_none, NULL_TREE);
16417 /* PARMS already refers to just the innermost parms, but the
16418 template parms in partial_spec_args had their levels lowered
16419 by tsubst, so we need to do the same for the parm list. We
16420 can't just tsubst the TREE_VEC itself, as tsubst wants to
16421 treat a TREE_VEC as an argument vector. */
16422 parms = copy_node (parms);
16423 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
16424 TREE_VEC_ELT (parms, i) =
16425 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
16429 partial_spec_args =
16430 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16431 add_to_template_args (outer_args,
16432 partial_spec_args),
16434 /*require_all_args=*/true,
16435 /*use_default_args=*/true);
16437 --processing_template_decl;
16439 if (partial_spec_args == error_mark_node)
16440 return error_mark_node;
16442 spec_args = get_class_bindings (parms,
16448 spec_args = add_to_template_args (outer_args, spec_args);
16449 list = tree_cons (spec_args, TREE_VALUE (t), list);
16450 TREE_TYPE (list) = TREE_TYPE (t);
16457 ambiguous_p = false;
16460 t = TREE_CHAIN (t);
16461 for (; t; t = TREE_CHAIN (t))
16463 fate = more_specialized_class (champ, t);
16470 t = TREE_CHAIN (t);
16473 ambiguous_p = true;
16482 for (t = list; t && t != champ; t = TREE_CHAIN (t))
16484 fate = more_specialized_class (champ, t);
16487 ambiguous_p = true;
16495 char *spaces = NULL;
16496 if (!(complain & tf_error))
16497 return error_mark_node;
16498 error ("ambiguous class template instantiation for %q#T", type);
16499 str = TREE_CHAIN (list) ? _("candidates are:") : _("candidate is:");
16500 for (t = list; t; t = TREE_CHAIN (t))
16502 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
16503 spaces = spaces ? spaces : get_spaces (str);
16506 return error_mark_node;
16512 /* Explicitly instantiate DECL. */
16515 do_decl_instantiation (tree decl, tree storage)
16517 tree result = NULL_TREE;
16520 if (!decl || decl == error_mark_node)
16521 /* An error occurred, for which grokdeclarator has already issued
16522 an appropriate message. */
16524 else if (! DECL_LANG_SPECIFIC (decl))
16526 error ("explicit instantiation of non-template %q#D", decl);
16529 else if (TREE_CODE (decl) == VAR_DECL)
16531 /* There is an asymmetry here in the way VAR_DECLs and
16532 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16533 the latter, the DECL we get back will be marked as a
16534 template instantiation, and the appropriate
16535 DECL_TEMPLATE_INFO will be set up. This does not happen for
16536 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16537 should handle VAR_DECLs as it currently handles
16539 if (!DECL_CLASS_SCOPE_P (decl))
16541 error ("%qD is not a static data member of a class template", decl);
16544 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16545 if (!result || TREE_CODE (result) != VAR_DECL)
16547 error ("no matching template for %qD found", decl);
16550 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16552 error ("type %qT for explicit instantiation %qD does not match "
16553 "declared type %qT", TREE_TYPE (result), decl,
16558 else if (TREE_CODE (decl) != FUNCTION_DECL)
16560 error ("explicit instantiation of %q#D", decl);
16566 /* Check for various error cases. Note that if the explicit
16567 instantiation is valid the RESULT will currently be marked as an
16568 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16569 until we get here. */
16571 if (DECL_TEMPLATE_SPECIALIZATION (result))
16573 /* DR 259 [temp.spec].
16575 Both an explicit instantiation and a declaration of an explicit
16576 specialization shall not appear in a program unless the explicit
16577 instantiation follows a declaration of the explicit specialization.
16579 For a given set of template parameters, if an explicit
16580 instantiation of a template appears after a declaration of an
16581 explicit specialization for that template, the explicit
16582 instantiation has no effect. */
16585 else if (DECL_EXPLICIT_INSTANTIATION (result))
16589 No program shall explicitly instantiate any template more
16592 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16593 the first instantiation was `extern' and the second is not,
16594 and EXTERN_P for the opposite case. */
16595 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16596 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16597 /* If an "extern" explicit instantiation follows an ordinary
16598 explicit instantiation, the template is instantiated. */
16602 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16604 error ("no matching template for %qD found", result);
16607 else if (!DECL_TEMPLATE_INFO (result))
16609 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16613 if (storage == NULL_TREE)
16615 else if (storage == ridpointers[(int) RID_EXTERN])
16617 if (!in_system_header && (cxx_dialect == cxx98))
16618 pedwarn (input_location, OPT_pedantic,
16619 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16624 error ("storage class %qD applied to template instantiation", storage);
16626 check_explicit_instantiation_namespace (result);
16627 mark_decl_instantiated (result, extern_p);
16629 instantiate_decl (result, /*defer_ok=*/1,
16630 /*expl_inst_class_mem_p=*/false);
16634 mark_class_instantiated (tree t, int extern_p)
16636 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16637 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16638 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16639 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16642 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16643 rest_of_type_compilation (t, 1);
16647 /* Called from do_type_instantiation through binding_table_foreach to
16648 do recursive instantiation for the type bound in ENTRY. */
16650 bt_instantiate_type_proc (binding_entry entry, void *data)
16652 tree storage = *(tree *) data;
16654 if (MAYBE_CLASS_TYPE_P (entry->type)
16655 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16656 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16659 /* Called from do_type_instantiation to instantiate a member
16660 (a member function or a static member variable) of an
16661 explicitly instantiated class template. */
16663 instantiate_class_member (tree decl, int extern_p)
16665 mark_decl_instantiated (decl, extern_p);
16667 instantiate_decl (decl, /*defer_ok=*/1,
16668 /*expl_inst_class_mem_p=*/true);
16671 /* Perform an explicit instantiation of template class T. STORAGE, if
16672 non-null, is the RID for extern, inline or static. COMPLAIN is
16673 nonzero if this is called from the parser, zero if called recursively,
16674 since the standard is unclear (as detailed below). */
16677 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16682 int previous_instantiation_extern_p = 0;
16684 if (TREE_CODE (t) == TYPE_DECL)
16687 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16689 error ("explicit instantiation of non-template type %qT", t);
16695 if (!COMPLETE_TYPE_P (t))
16697 if (complain & tf_error)
16698 error ("explicit instantiation of %q#T before definition of template",
16703 if (storage != NULL_TREE)
16705 if (!in_system_header)
16707 if (storage == ridpointers[(int) RID_EXTERN])
16709 if (cxx_dialect == cxx98)
16710 pedwarn (input_location, OPT_pedantic,
16711 "ISO C++ 1998 forbids the use of %<extern%> on "
16712 "explicit instantiations");
16715 pedwarn (input_location, OPT_pedantic,
16716 "ISO C++ forbids the use of %qE"
16717 " on explicit instantiations", storage);
16720 if (storage == ridpointers[(int) RID_INLINE])
16722 else if (storage == ridpointers[(int) RID_EXTERN])
16724 else if (storage == ridpointers[(int) RID_STATIC])
16728 error ("storage class %qD applied to template instantiation",
16734 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
16736 /* DR 259 [temp.spec].
16738 Both an explicit instantiation and a declaration of an explicit
16739 specialization shall not appear in a program unless the explicit
16740 instantiation follows a declaration of the explicit specialization.
16742 For a given set of template parameters, if an explicit
16743 instantiation of a template appears after a declaration of an
16744 explicit specialization for that template, the explicit
16745 instantiation has no effect. */
16748 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
16752 No program shall explicitly instantiate any template more
16755 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
16756 instantiation was `extern'. If EXTERN_P then the second is.
16757 These cases are OK. */
16758 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
16760 if (!previous_instantiation_extern_p && !extern_p
16761 && (complain & tf_error))
16762 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
16764 /* If we've already instantiated the template, just return now. */
16765 if (!CLASSTYPE_INTERFACE_ONLY (t))
16769 check_explicit_instantiation_namespace (TYPE_NAME (t));
16770 mark_class_instantiated (t, extern_p);
16778 /* In contrast to implicit instantiation, where only the
16779 declarations, and not the definitions, of members are
16780 instantiated, we have here:
16784 The explicit instantiation of a class template specialization
16785 implies the instantiation of all of its members not
16786 previously explicitly specialized in the translation unit
16787 containing the explicit instantiation.
16789 Of course, we can't instantiate member template classes, since
16790 we don't have any arguments for them. Note that the standard
16791 is unclear on whether the instantiation of the members are
16792 *explicit* instantiations or not. However, the most natural
16793 interpretation is that it should be an explicit instantiation. */
16796 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
16797 if (TREE_CODE (tmp) == FUNCTION_DECL
16798 && DECL_TEMPLATE_INSTANTIATION (tmp))
16799 instantiate_class_member (tmp, extern_p);
16801 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
16802 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
16803 instantiate_class_member (tmp, extern_p);
16805 if (CLASSTYPE_NESTED_UTDS (t))
16806 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
16807 bt_instantiate_type_proc, &storage);
16811 /* Given a function DECL, which is a specialization of TMPL, modify
16812 DECL to be a re-instantiation of TMPL with the same template
16813 arguments. TMPL should be the template into which tsubst'ing
16814 should occur for DECL, not the most general template.
16816 One reason for doing this is a scenario like this:
16819 void f(const T&, int i);
16821 void g() { f(3, 7); }
16824 void f(const T& t, const int i) { }
16826 Note that when the template is first instantiated, with
16827 instantiate_template, the resulting DECL will have no name for the
16828 first parameter, and the wrong type for the second. So, when we go
16829 to instantiate the DECL, we regenerate it. */
16832 regenerate_decl_from_template (tree decl, tree tmpl)
16834 /* The arguments used to instantiate DECL, from the most general
16839 args = DECL_TI_ARGS (decl);
16840 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
16842 /* Make sure that we can see identifiers, and compute access
16844 push_access_scope (decl);
16846 if (TREE_CODE (decl) == FUNCTION_DECL)
16854 args_depth = TMPL_ARGS_DEPTH (args);
16855 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16856 if (args_depth > parms_depth)
16857 args = get_innermost_template_args (args, parms_depth);
16859 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16860 args, tf_error, NULL_TREE);
16862 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16865 /* Merge parameter declarations. */
16866 decl_parm = skip_artificial_parms_for (decl,
16867 DECL_ARGUMENTS (decl));
16869 = skip_artificial_parms_for (code_pattern,
16870 DECL_ARGUMENTS (code_pattern));
16871 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16876 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16877 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16878 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16880 parm_type = type_decays_to (parm_type);
16881 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16882 TREE_TYPE (decl_parm) = parm_type;
16883 attributes = DECL_ATTRIBUTES (pattern_parm);
16884 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16886 DECL_ATTRIBUTES (decl_parm) = attributes;
16887 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16889 decl_parm = DECL_CHAIN (decl_parm);
16890 pattern_parm = DECL_CHAIN (pattern_parm);
16892 /* Merge any parameters that match with the function parameter
16894 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16897 tree expanded_types;
16898 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16899 the parameters in this function parameter pack. */
16900 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16901 args, tf_error, NULL_TREE);
16902 len = TREE_VEC_LENGTH (expanded_types);
16903 for (i = 0; i < len; i++)
16908 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16909 /* Rename the parameter to include the index. */
16910 DECL_NAME (decl_parm) =
16911 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16912 parm_type = TREE_VEC_ELT (expanded_types, i);
16913 parm_type = type_decays_to (parm_type);
16914 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16915 TREE_TYPE (decl_parm) = parm_type;
16916 attributes = DECL_ATTRIBUTES (pattern_parm);
16917 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16919 DECL_ATTRIBUTES (decl_parm) = attributes;
16920 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16922 decl_parm = DECL_CHAIN (decl_parm);
16925 /* Merge additional specifiers from the CODE_PATTERN. */
16926 if (DECL_DECLARED_INLINE_P (code_pattern)
16927 && !DECL_DECLARED_INLINE_P (decl))
16928 DECL_DECLARED_INLINE_P (decl) = 1;
16930 else if (TREE_CODE (decl) == VAR_DECL)
16932 DECL_INITIAL (decl) =
16933 tsubst_expr (DECL_INITIAL (code_pattern), args,
16934 tf_error, DECL_TI_TEMPLATE (decl),
16935 /*integral_constant_expression_p=*/false);
16936 if (VAR_HAD_UNKNOWN_BOUND (decl))
16937 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
16938 tf_error, DECL_TI_TEMPLATE (decl));
16941 gcc_unreachable ();
16943 pop_access_scope (decl);
16946 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16947 substituted to get DECL. */
16950 template_for_substitution (tree decl)
16952 tree tmpl = DECL_TI_TEMPLATE (decl);
16954 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16955 for the instantiation. This is not always the most general
16956 template. Consider, for example:
16959 struct S { template <class U> void f();
16960 template <> void f<int>(); };
16962 and an instantiation of S<double>::f<int>. We want TD to be the
16963 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16964 while (/* An instantiation cannot have a definition, so we need a
16965 more general template. */
16966 DECL_TEMPLATE_INSTANTIATION (tmpl)
16967 /* We must also deal with friend templates. Given:
16969 template <class T> struct S {
16970 template <class U> friend void f() {};
16973 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16974 so far as the language is concerned, but that's still
16975 where we get the pattern for the instantiation from. On
16976 other hand, if the definition comes outside the class, say:
16978 template <class T> struct S {
16979 template <class U> friend void f();
16981 template <class U> friend void f() {}
16983 we don't need to look any further. That's what the check for
16984 DECL_INITIAL is for. */
16985 || (TREE_CODE (decl) == FUNCTION_DECL
16986 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16987 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16989 /* The present template, TD, should not be a definition. If it
16990 were a definition, we should be using it! Note that we
16991 cannot restructure the loop to just keep going until we find
16992 a template with a definition, since that might go too far if
16993 a specialization was declared, but not defined. */
16994 gcc_assert (TREE_CODE (decl) != VAR_DECL
16995 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16997 /* Fetch the more general template. */
16998 tmpl = DECL_TI_TEMPLATE (tmpl);
17004 /* Returns true if we need to instantiate this template instance even if we
17005 know we aren't going to emit it.. */
17008 always_instantiate_p (tree decl)
17010 /* We always instantiate inline functions so that we can inline them. An
17011 explicit instantiation declaration prohibits implicit instantiation of
17012 non-inline functions. With high levels of optimization, we would
17013 normally inline non-inline functions -- but we're not allowed to do
17014 that for "extern template" functions. Therefore, we check
17015 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17016 return ((TREE_CODE (decl) == FUNCTION_DECL
17017 && DECL_DECLARED_INLINE_P (decl))
17018 /* And we need to instantiate static data members so that
17019 their initializers are available in integral constant
17021 || (TREE_CODE (decl) == VAR_DECL
17022 && decl_maybe_constant_var_p (decl)));
17025 /* Produce the definition of D, a _DECL generated from a template. If
17026 DEFER_OK is nonzero, then we don't have to actually do the
17027 instantiation now; we just have to do it sometime. Normally it is
17028 an error if this is an explicit instantiation but D is undefined.
17029 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17030 explicitly instantiated class template. */
17033 instantiate_decl (tree d, int defer_ok,
17034 bool expl_inst_class_mem_p)
17036 tree tmpl = DECL_TI_TEMPLATE (d);
17043 bool pattern_defined;
17045 location_t saved_loc = input_location;
17048 /* This function should only be used to instantiate templates for
17049 functions and static member variables. */
17050 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17051 || TREE_CODE (d) == VAR_DECL);
17053 /* Variables are never deferred; if instantiation is required, they
17054 are instantiated right away. That allows for better code in the
17055 case that an expression refers to the value of the variable --
17056 if the variable has a constant value the referring expression can
17057 take advantage of that fact. */
17058 if (TREE_CODE (d) == VAR_DECL
17059 || DECL_DECLARED_CONSTEXPR_P (d))
17062 /* Don't instantiate cloned functions. Instead, instantiate the
17063 functions they cloned. */
17064 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17065 d = DECL_CLONED_FUNCTION (d);
17067 if (DECL_TEMPLATE_INSTANTIATED (d)
17068 || DECL_TEMPLATE_SPECIALIZATION (d))
17069 /* D has already been instantiated or explicitly specialized, so
17070 there's nothing for us to do here.
17072 It might seem reasonable to check whether or not D is an explicit
17073 instantiation, and, if so, stop here. But when an explicit
17074 instantiation is deferred until the end of the compilation,
17075 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17076 the instantiation. */
17079 /* Check to see whether we know that this template will be
17080 instantiated in some other file, as with "extern template"
17082 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17084 /* In general, we do not instantiate such templates. */
17085 if (external_p && !always_instantiate_p (d))
17088 gen_tmpl = most_general_template (tmpl);
17089 gen_args = DECL_TI_ARGS (d);
17091 if (tmpl != gen_tmpl)
17092 /* We should already have the extra args. */
17093 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17094 == TMPL_ARGS_DEPTH (gen_args));
17095 /* And what's in the hash table should match D. */
17096 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17097 || spec == NULL_TREE);
17099 /* This needs to happen before any tsubsting. */
17100 if (! push_tinst_level (d))
17103 timevar_push (TV_PARSE);
17105 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
17106 for the instantiation. */
17107 td = template_for_substitution (d);
17108 code_pattern = DECL_TEMPLATE_RESULT (td);
17110 /* We should never be trying to instantiate a member of a class
17111 template or partial specialization. */
17112 gcc_assert (d != code_pattern);
17114 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
17115 || DECL_TEMPLATE_SPECIALIZATION (td))
17116 /* In the case of a friend template whose definition is provided
17117 outside the class, we may have too many arguments. Drop the
17118 ones we don't need. The same is true for specializations. */
17119 args = get_innermost_template_args
17120 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
17124 if (TREE_CODE (d) == FUNCTION_DECL)
17125 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
17127 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
17129 /* We may be in the middle of deferred access check. Disable it now. */
17130 push_deferring_access_checks (dk_no_deferred);
17132 /* Unless an explicit instantiation directive has already determined
17133 the linkage of D, remember that a definition is available for
17135 if (pattern_defined
17136 && !DECL_INTERFACE_KNOWN (d)
17137 && !DECL_NOT_REALLY_EXTERN (d))
17138 mark_definable (d);
17140 input_location = DECL_SOURCE_LOCATION (d);
17142 /* If D is a member of an explicitly instantiated class template,
17143 and no definition is available, treat it like an implicit
17145 if (!pattern_defined && expl_inst_class_mem_p
17146 && DECL_EXPLICIT_INSTANTIATION (d))
17148 DECL_NOT_REALLY_EXTERN (d) = 0;
17149 DECL_INTERFACE_KNOWN (d) = 0;
17150 SET_DECL_IMPLICIT_INSTANTIATION (d);
17153 /* Recheck the substitutions to obtain any warning messages
17154 about ignoring cv qualifiers. Don't do this for artificial decls,
17155 as it breaks the context-sensitive substitution for lambda op(). */
17156 if (!defer_ok && !DECL_ARTIFICIAL (d))
17158 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
17159 tree type = TREE_TYPE (gen);
17161 /* Make sure that we can see identifiers, and compute access
17162 correctly. D is already the target FUNCTION_DECL with the
17164 push_access_scope (d);
17166 if (TREE_CODE (gen) == FUNCTION_DECL)
17168 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
17169 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
17171 /* Don't simply tsubst the function type, as that will give
17172 duplicate warnings about poor parameter qualifications.
17173 The function arguments are the same as the decl_arguments
17174 without the top level cv qualifiers. */
17175 type = TREE_TYPE (type);
17177 tsubst (type, gen_args, tf_warning_or_error, d);
17179 pop_access_scope (d);
17182 /* Defer all other templates, unless we have been explicitly
17183 forbidden from doing so. */
17184 if (/* If there is no definition, we cannot instantiate the
17187 /* If it's OK to postpone instantiation, do so. */
17189 /* If this is a static data member that will be defined
17190 elsewhere, we don't want to instantiate the entire data
17191 member, but we do want to instantiate the initializer so that
17192 we can substitute that elsewhere. */
17193 || (external_p && TREE_CODE (d) == VAR_DECL))
17195 /* The definition of the static data member is now required so
17196 we must substitute the initializer. */
17197 if (TREE_CODE (d) == VAR_DECL
17198 && !DECL_INITIAL (d)
17199 && DECL_INITIAL (code_pattern))
17203 bool const_init = false;
17205 ns = decl_namespace_context (d);
17206 push_nested_namespace (ns);
17207 push_nested_class (DECL_CONTEXT (d));
17208 init = tsubst_expr (DECL_INITIAL (code_pattern),
17210 tf_warning_or_error, NULL_TREE,
17211 /*integral_constant_expression_p=*/false);
17212 /* Make sure the initializer is still constant, in case of
17213 circular dependency (template/instantiate6.C). */
17215 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17216 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
17217 /*asmspec_tree=*/NULL_TREE,
17218 LOOKUP_ONLYCONVERTING);
17219 pop_nested_class ();
17220 pop_nested_namespace (ns);
17223 /* We restore the source position here because it's used by
17224 add_pending_template. */
17225 input_location = saved_loc;
17227 if (at_eof && !pattern_defined
17228 && DECL_EXPLICIT_INSTANTIATION (d)
17229 && DECL_NOT_REALLY_EXTERN (d))
17232 The definition of a non-exported function template, a
17233 non-exported member function template, or a non-exported
17234 member function or static data member of a class template
17235 shall be present in every translation unit in which it is
17236 explicitly instantiated. */
17237 permerror (input_location, "explicit instantiation of %qD "
17238 "but no definition available", d);
17240 /* If we're in unevaluated context, we just wanted to get the
17241 constant value; this isn't an odr use, so don't queue
17242 a full instantiation. */
17243 if (cp_unevaluated_operand != 0)
17245 /* ??? Historically, we have instantiated inline functions, even
17246 when marked as "extern template". */
17247 if (!(external_p && TREE_CODE (d) == VAR_DECL))
17248 add_pending_template (d);
17251 /* Tell the repository that D is available in this translation unit
17252 -- and see if it is supposed to be instantiated here. */
17253 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
17255 /* In a PCH file, despite the fact that the repository hasn't
17256 requested instantiation in the PCH it is still possible that
17257 an instantiation will be required in a file that includes the
17260 add_pending_template (d);
17261 /* Instantiate inline functions so that the inliner can do its
17262 job, even though we'll not be emitting a copy of this
17264 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
17268 need_push = !cfun || !global_bindings_p ();
17270 push_to_top_level ();
17272 /* Mark D as instantiated so that recursive calls to
17273 instantiate_decl do not try to instantiate it again. */
17274 DECL_TEMPLATE_INSTANTIATED (d) = 1;
17276 /* Regenerate the declaration in case the template has been modified
17277 by a subsequent redeclaration. */
17278 regenerate_decl_from_template (d, td);
17280 /* We already set the file and line above. Reset them now in case
17281 they changed as a result of calling regenerate_decl_from_template. */
17282 input_location = DECL_SOURCE_LOCATION (d);
17284 if (TREE_CODE (d) == VAR_DECL)
17287 bool const_init = false;
17289 /* Clear out DECL_RTL; whatever was there before may not be right
17290 since we've reset the type of the declaration. */
17291 SET_DECL_RTL (d, NULL);
17292 DECL_IN_AGGR_P (d) = 0;
17294 /* The initializer is placed in DECL_INITIAL by
17295 regenerate_decl_from_template so we don't need to
17296 push/pop_access_scope again here. Pull it out so that
17297 cp_finish_decl can process it. */
17298 init = DECL_INITIAL (d);
17299 DECL_INITIAL (d) = NULL_TREE;
17300 DECL_INITIALIZED_P (d) = 0;
17302 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
17303 initializer. That function will defer actual emission until
17304 we have a chance to determine linkage. */
17305 DECL_EXTERNAL (d) = 0;
17307 /* Enter the scope of D so that access-checking works correctly. */
17308 push_nested_class (DECL_CONTEXT (d));
17309 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
17310 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
17311 pop_nested_class ();
17313 else if (TREE_CODE (d) == FUNCTION_DECL)
17315 htab_t saved_local_specializations;
17320 /* Save away the current list, in case we are instantiating one
17321 template from within the body of another. */
17322 saved_local_specializations = local_specializations;
17324 /* Set up the list of local specializations. */
17325 local_specializations = htab_create (37,
17326 hash_local_specialization,
17327 eq_local_specializations,
17330 /* Set up context. */
17331 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
17333 /* Create substitution entries for the parameters. */
17334 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
17335 tmpl_parm = DECL_ARGUMENTS (subst_decl);
17336 spec_parm = DECL_ARGUMENTS (d);
17337 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
17339 register_local_specialization (spec_parm, tmpl_parm);
17340 spec_parm = skip_artificial_parms_for (d, spec_parm);
17341 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
17343 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17345 register_local_specialization (spec_parm, tmpl_parm);
17346 tmpl_parm = DECL_CHAIN (tmpl_parm);
17347 spec_parm = DECL_CHAIN (spec_parm);
17349 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
17351 /* Register the (value) argument pack as a specialization of
17352 TMPL_PARM, then move on. */
17353 tree argpack = make_fnparm_pack (spec_parm);
17354 register_local_specialization (argpack, tmpl_parm);
17355 tmpl_parm = DECL_CHAIN (tmpl_parm);
17356 spec_parm = NULL_TREE;
17358 gcc_assert (!spec_parm);
17360 /* Substitute into the body of the function. */
17361 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
17362 tf_warning_or_error, tmpl,
17363 /*integral_constant_expression_p=*/false);
17365 /* Set the current input_location to the end of the function
17366 so that finish_function knows where we are. */
17367 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
17369 /* We don't need the local specializations any more. */
17370 htab_delete (local_specializations);
17371 local_specializations = saved_local_specializations;
17373 /* Finish the function. */
17374 d = finish_function (0);
17375 expand_or_defer_fn (d);
17378 /* We're not deferring instantiation any more. */
17379 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
17382 pop_from_top_level ();
17385 input_location = saved_loc;
17386 pop_deferring_access_checks ();
17387 pop_tinst_level ();
17389 timevar_pop (TV_PARSE);
17394 /* Run through the list of templates that we wish we could
17395 instantiate, and instantiate any we can. RETRIES is the
17396 number of times we retry pending template instantiation. */
17399 instantiate_pending_templates (int retries)
17402 location_t saved_loc = input_location;
17404 /* Instantiating templates may trigger vtable generation. This in turn
17405 may require further template instantiations. We place a limit here
17406 to avoid infinite loop. */
17407 if (pending_templates && retries >= max_tinst_depth)
17409 tree decl = pending_templates->tinst->decl;
17411 error ("template instantiation depth exceeds maximum of %d"
17412 " instantiating %q+D, possibly from virtual table generation"
17413 " (use -ftemplate-depth= to increase the maximum)",
17414 max_tinst_depth, decl);
17415 if (TREE_CODE (decl) == FUNCTION_DECL)
17416 /* Pretend that we defined it. */
17417 DECL_INITIAL (decl) = error_mark_node;
17423 struct pending_template **t = &pending_templates;
17424 struct pending_template *last = NULL;
17428 tree instantiation = reopen_tinst_level ((*t)->tinst);
17429 bool complete = false;
17431 if (TYPE_P (instantiation))
17435 if (!COMPLETE_TYPE_P (instantiation))
17437 instantiate_class_template (instantiation);
17438 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
17439 for (fn = TYPE_METHODS (instantiation);
17441 fn = TREE_CHAIN (fn))
17442 if (! DECL_ARTIFICIAL (fn))
17443 instantiate_decl (fn,
17445 /*expl_inst_class_mem_p=*/false);
17446 if (COMPLETE_TYPE_P (instantiation))
17450 complete = COMPLETE_TYPE_P (instantiation);
17454 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
17455 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
17458 = instantiate_decl (instantiation,
17460 /*expl_inst_class_mem_p=*/false);
17461 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
17465 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
17466 || DECL_TEMPLATE_INSTANTIATED (instantiation));
17470 /* If INSTANTIATION has been instantiated, then we don't
17471 need to consider it again in the future. */
17479 current_tinst_level = NULL;
17481 last_pending_template = last;
17483 while (reconsider);
17485 input_location = saved_loc;
17488 /* Substitute ARGVEC into T, which is a list of initializers for
17489 either base class or a non-static data member. The TREE_PURPOSEs
17490 are DECLs, and the TREE_VALUEs are the initializer values. Used by
17491 instantiate_decl. */
17494 tsubst_initializer_list (tree t, tree argvec)
17496 tree inits = NULL_TREE;
17498 for (; t; t = TREE_CHAIN (t))
17502 tree expanded_bases = NULL_TREE;
17503 tree expanded_arguments = NULL_TREE;
17506 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
17511 /* Expand the base class expansion type into separate base
17513 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
17514 tf_warning_or_error,
17516 if (expanded_bases == error_mark_node)
17519 /* We'll be building separate TREE_LISTs of arguments for
17521 len = TREE_VEC_LENGTH (expanded_bases);
17522 expanded_arguments = make_tree_vec (len);
17523 for (i = 0; i < len; i++)
17524 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
17526 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
17527 expand each argument in the TREE_VALUE of t. */
17528 expr = make_node (EXPR_PACK_EXPANSION);
17529 PACK_EXPANSION_PARAMETER_PACKS (expr) =
17530 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
17532 if (TREE_VALUE (t) == void_type_node)
17533 /* VOID_TYPE_NODE is used to indicate
17534 value-initialization. */
17536 for (i = 0; i < len; i++)
17537 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
17541 /* Substitute parameter packs into each argument in the
17543 in_base_initializer = 1;
17544 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
17546 tree expanded_exprs;
17548 /* Expand the argument. */
17549 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17551 = tsubst_pack_expansion (expr, argvec,
17552 tf_warning_or_error,
17554 if (expanded_exprs == error_mark_node)
17557 /* Prepend each of the expanded expressions to the
17558 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17559 for (i = 0; i < len; i++)
17561 TREE_VEC_ELT (expanded_arguments, i) =
17562 tree_cons (NULL_TREE,
17563 TREE_VEC_ELT (expanded_exprs, i),
17564 TREE_VEC_ELT (expanded_arguments, i));
17567 in_base_initializer = 0;
17569 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17570 since we built them backwards. */
17571 for (i = 0; i < len; i++)
17573 TREE_VEC_ELT (expanded_arguments, i) =
17574 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17579 for (i = 0; i < len; ++i)
17581 if (expanded_bases)
17583 decl = TREE_VEC_ELT (expanded_bases, i);
17584 decl = expand_member_init (decl);
17585 init = TREE_VEC_ELT (expanded_arguments, i);
17589 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17590 tf_warning_or_error, NULL_TREE);
17592 decl = expand_member_init (decl);
17593 if (decl && !DECL_P (decl))
17594 in_base_initializer = 1;
17596 init = TREE_VALUE (t);
17597 if (init != void_type_node)
17598 init = tsubst_expr (init, argvec,
17599 tf_warning_or_error, NULL_TREE,
17600 /*integral_constant_expression_p=*/false);
17601 in_base_initializer = 0;
17606 init = build_tree_list (decl, init);
17607 TREE_CHAIN (init) = inits;
17615 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17618 set_current_access_from_decl (tree decl)
17620 if (TREE_PRIVATE (decl))
17621 current_access_specifier = access_private_node;
17622 else if (TREE_PROTECTED (decl))
17623 current_access_specifier = access_protected_node;
17625 current_access_specifier = access_public_node;
17628 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17629 is the instantiation (which should have been created with
17630 start_enum) and ARGS are the template arguments to use. */
17633 tsubst_enum (tree tag, tree newtag, tree args)
17637 if (SCOPED_ENUM_P (newtag))
17638 begin_scope (sk_scoped_enum, newtag);
17640 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17645 decl = TREE_VALUE (e);
17646 /* Note that in a template enum, the TREE_VALUE is the
17647 CONST_DECL, not the corresponding INTEGER_CST. */
17648 value = tsubst_expr (DECL_INITIAL (decl),
17649 args, tf_warning_or_error, NULL_TREE,
17650 /*integral_constant_expression_p=*/true);
17652 /* Give this enumeration constant the correct access. */
17653 set_current_access_from_decl (decl);
17655 /* Actually build the enumerator itself. */
17657 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
17660 if (SCOPED_ENUM_P (newtag))
17663 finish_enum_value_list (newtag);
17664 finish_enum (newtag);
17666 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17667 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17670 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17671 its type -- but without substituting the innermost set of template
17672 arguments. So, innermost set of template parameters will appear in
17676 get_mostly_instantiated_function_type (tree decl)
17684 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17685 targs = DECL_TI_ARGS (decl);
17686 tparms = DECL_TEMPLATE_PARMS (tmpl);
17687 parm_depth = TMPL_PARMS_DEPTH (tparms);
17689 /* There should be as many levels of arguments as there are levels
17691 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
17693 fn_type = TREE_TYPE (tmpl);
17695 if (parm_depth == 1)
17696 /* No substitution is necessary. */
17700 int i, save_access_control;
17703 /* Replace the innermost level of the TARGS with NULL_TREEs to
17704 let tsubst know not to substitute for those parameters. */
17705 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
17706 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
17707 SET_TMPL_ARGS_LEVEL (partial_args, i,
17708 TMPL_ARGS_LEVEL (targs, i));
17709 SET_TMPL_ARGS_LEVEL (partial_args,
17710 TMPL_ARGS_DEPTH (targs),
17711 make_tree_vec (DECL_NTPARMS (tmpl)));
17713 /* Disable access control as this function is used only during
17715 save_access_control = flag_access_control;
17716 flag_access_control = 0;
17718 ++processing_template_decl;
17719 /* Now, do the (partial) substitution to figure out the
17720 appropriate function type. */
17721 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
17722 --processing_template_decl;
17724 /* Substitute into the template parameters to obtain the real
17725 innermost set of parameters. This step is important if the
17726 innermost set of template parameters contains value
17727 parameters whose types depend on outer template parameters. */
17728 TREE_VEC_LENGTH (partial_args)--;
17729 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
17731 flag_access_control = save_access_control;
17737 /* Return truthvalue if we're processing a template different from
17738 the last one involved in diagnostics. */
17740 problematic_instantiation_changed (void)
17742 return last_template_error_tick != tinst_level_tick;
17745 /* Remember current template involved in diagnostics. */
17747 record_last_problematic_instantiation (void)
17749 last_template_error_tick = tinst_level_tick;
17752 struct tinst_level *
17753 current_instantiation (void)
17755 return current_tinst_level;
17758 /* [temp.param] Check that template non-type parm TYPE is of an allowable
17759 type. Return zero for ok, nonzero for disallowed. Issue error and
17760 warning messages under control of COMPLAIN. */
17763 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
17765 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
17767 else if (POINTER_TYPE_P (type))
17769 else if (TYPE_PTR_TO_MEMBER_P (type))
17771 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
17773 else if (TREE_CODE (type) == TYPENAME_TYPE)
17776 if (complain & tf_error)
17777 error ("%q#T is not a valid type for a template constant parameter", type);
17781 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
17782 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
17785 dependent_type_p_r (tree type)
17791 A type is dependent if it is:
17793 -- a template parameter. Template template parameters are types
17794 for us (since TYPE_P holds true for them) so we handle
17796 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17797 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
17799 /* -- a qualified-id with a nested-name-specifier which contains a
17800 class-name that names a dependent type or whose unqualified-id
17801 names a dependent type. */
17802 if (TREE_CODE (type) == TYPENAME_TYPE)
17804 /* -- a cv-qualified type where the cv-unqualified type is
17806 type = TYPE_MAIN_VARIANT (type);
17807 /* -- a compound type constructed from any dependent type. */
17808 if (TYPE_PTR_TO_MEMBER_P (type))
17809 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
17810 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
17812 else if (TREE_CODE (type) == POINTER_TYPE
17813 || TREE_CODE (type) == REFERENCE_TYPE)
17814 return dependent_type_p (TREE_TYPE (type));
17815 else if (TREE_CODE (type) == FUNCTION_TYPE
17816 || TREE_CODE (type) == METHOD_TYPE)
17820 if (dependent_type_p (TREE_TYPE (type)))
17822 for (arg_type = TYPE_ARG_TYPES (type);
17824 arg_type = TREE_CHAIN (arg_type))
17825 if (dependent_type_p (TREE_VALUE (arg_type)))
17829 /* -- an array type constructed from any dependent type or whose
17830 size is specified by a constant expression that is
17833 We checked for type- and value-dependence of the bounds in
17834 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
17835 if (TREE_CODE (type) == ARRAY_TYPE)
17837 if (TYPE_DOMAIN (type)
17838 && dependent_type_p (TYPE_DOMAIN (type)))
17840 return dependent_type_p (TREE_TYPE (type));
17843 /* -- a template-id in which either the template name is a template
17845 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
17847 /* ... or any of the template arguments is a dependent type or
17848 an expression that is type-dependent or value-dependent. */
17849 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
17850 && (any_dependent_template_arguments_p
17851 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
17854 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
17855 argument of the `typeof' expression is not type-dependent, then
17856 it should already been have resolved. */
17857 if (TREE_CODE (type) == TYPEOF_TYPE
17858 || TREE_CODE (type) == DECLTYPE_TYPE)
17861 /* A template argument pack is dependent if any of its packed
17863 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
17865 tree args = ARGUMENT_PACK_ARGS (type);
17866 int i, len = TREE_VEC_LENGTH (args);
17867 for (i = 0; i < len; ++i)
17868 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17872 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17873 be template parameters. */
17874 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17877 /* The standard does not specifically mention types that are local
17878 to template functions or local classes, but they should be
17879 considered dependent too. For example:
17881 template <int I> void f() {
17886 The size of `E' cannot be known until the value of `I' has been
17887 determined. Therefore, `E' must be considered dependent. */
17888 scope = TYPE_CONTEXT (type);
17889 if (scope && TYPE_P (scope))
17890 return dependent_type_p (scope);
17891 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17892 return type_dependent_expression_p (scope);
17894 /* Other types are non-dependent. */
17898 /* Returns TRUE if TYPE is dependent, in the sense of
17899 [temp.dep.type]. */
17902 dependent_type_p (tree type)
17904 /* If there are no template parameters in scope, then there can't be
17905 any dependent types. */
17906 if (!processing_template_decl)
17908 /* If we are not processing a template, then nobody should be
17909 providing us with a dependent type. */
17911 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17915 /* If the type is NULL, we have not computed a type for the entity
17916 in question; in that case, the type is dependent. */
17920 /* Erroneous types can be considered non-dependent. */
17921 if (type == error_mark_node)
17924 /* If we have not already computed the appropriate value for TYPE,
17926 if (!TYPE_DEPENDENT_P_VALID (type))
17928 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17929 TYPE_DEPENDENT_P_VALID (type) = 1;
17932 return TYPE_DEPENDENT_P (type);
17935 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17936 lookup. In other words, a dependent type that is not the current
17940 dependent_scope_p (tree scope)
17942 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17943 && !currently_open_class (scope));
17946 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17947 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17950 /* FIXME this predicate is not appropriate for general expressions; the
17951 predicates we want instead are "valid constant expression, value
17952 dependent or not?", "really constant expression, not value dependent?"
17953 and "instantiation-dependent?". Try to integrate with
17954 potential_constant_expression?
17956 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
17957 (what about instantiation-dependent constant-expressions?)
17958 is_late_template_attribute: defer if instantiation-dependent.
17959 compute_array_index_type: proceed if constant and not t- or v-dependent
17960 if instantiation-dependent, need to remember full expression
17961 uses_template_parms: FIXME - need to audit callers
17962 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
17963 dependent_type_p [array_type]: dependent if index type is dependent
17965 static_assert - instantiation-dependent */
17968 value_dependent_expression_p (tree expression)
17970 if (!processing_template_decl)
17973 /* A name declared with a dependent type. */
17974 if (DECL_P (expression) && type_dependent_expression_p (expression))
17977 switch (TREE_CODE (expression))
17979 case IDENTIFIER_NODE:
17980 /* A name that has not been looked up -- must be dependent. */
17983 case TEMPLATE_PARM_INDEX:
17984 /* A non-type template parm. */
17988 /* A non-type template parm. */
17989 if (DECL_TEMPLATE_PARM_P (expression))
17991 return value_dependent_expression_p (DECL_INITIAL (expression));
17994 /* A constant with integral or enumeration type and is initialized
17995 with an expression that is value-dependent. */
17996 if (DECL_INITIAL (expression)
17997 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17998 && value_dependent_expression_p (DECL_INITIAL (expression)))
18002 case DYNAMIC_CAST_EXPR:
18003 case STATIC_CAST_EXPR:
18004 case CONST_CAST_EXPR:
18005 case REINTERPRET_CAST_EXPR:
18007 /* These expressions are value-dependent if the type to which
18008 the cast occurs is dependent or the expression being casted
18009 is value-dependent. */
18011 tree type = TREE_TYPE (expression);
18013 if (dependent_type_p (type))
18016 /* A functional cast has a list of operands. */
18017 expression = TREE_OPERAND (expression, 0);
18020 /* If there are no operands, it must be an expression such
18021 as "int()". This should not happen for aggregate types
18022 because it would form non-constant expressions. */
18023 gcc_assert (cxx_dialect >= cxx0x
18024 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18029 if (TREE_CODE (expression) == TREE_LIST)
18030 return any_value_dependent_elements_p (expression);
18032 return value_dependent_expression_p (expression);
18037 /* A `sizeof' expression is value-dependent if the operand is
18038 type-dependent or is a pack expansion. */
18039 expression = TREE_OPERAND (expression, 0);
18040 if (PACK_EXPANSION_P (expression))
18042 else if (TYPE_P (expression))
18043 return dependent_type_p (expression);
18044 return type_dependent_expression_p (expression);
18046 case AT_ENCODE_EXPR:
18047 /* An 'encode' expression is value-dependent if the operand is
18049 expression = TREE_OPERAND (expression, 0);
18050 return dependent_type_p (expression);
18052 case NOEXCEPT_EXPR:
18053 expression = TREE_OPERAND (expression, 0);
18054 /* FIXME why check value-dependency? */
18055 return (type_dependent_expression_p (expression)
18056 || value_dependent_expression_p (expression));
18060 tree name = TREE_OPERAND (expression, 1);
18061 return value_dependent_expression_p (name);
18064 case COMPONENT_REF:
18065 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18066 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18068 case NONTYPE_ARGUMENT_PACK:
18069 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18070 is value-dependent. */
18072 tree values = ARGUMENT_PACK_ARGS (expression);
18073 int i, len = TREE_VEC_LENGTH (values);
18075 for (i = 0; i < len; ++i)
18076 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
18084 tree type2 = TRAIT_EXPR_TYPE2 (expression);
18085 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
18086 || (type2 ? dependent_type_p (type2) : false));
18090 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
18091 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
18095 tree op = TREE_OPERAND (expression, 0);
18096 return (value_dependent_expression_p (op)
18097 || has_value_dependent_address (op));
18102 tree fn = get_callee_fndecl (expression);
18104 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
18106 nargs = call_expr_nargs (expression);
18107 for (i = 0; i < nargs; ++i)
18109 tree op = CALL_EXPR_ARG (expression, i);
18110 /* In a call to a constexpr member function, look through the
18111 implicit ADDR_EXPR on the object argument so that it doesn't
18112 cause the call to be considered value-dependent. We also
18113 look through it in potential_constant_expression. */
18114 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
18115 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
18116 && TREE_CODE (op) == ADDR_EXPR)
18117 op = TREE_OPERAND (op, 0);
18118 if (value_dependent_expression_p (op))
18125 /* A constant expression is value-dependent if any subexpression is
18126 value-dependent. */
18127 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
18129 case tcc_reference:
18131 return (value_dependent_expression_p
18132 (TREE_OPERAND (expression, 0)));
18134 case tcc_comparison:
18136 return ((value_dependent_expression_p
18137 (TREE_OPERAND (expression, 0)))
18138 || (value_dependent_expression_p
18139 (TREE_OPERAND (expression, 1))));
18141 case tcc_expression:
18145 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
18146 /* In some cases, some of the operands may be missing.
18147 (For example, in the case of PREDECREMENT_EXPR, the
18148 amount to increment by may be missing.) That doesn't
18149 make the expression dependent. */
18150 if (TREE_OPERAND (expression, i)
18151 && (value_dependent_expression_p
18152 (TREE_OPERAND (expression, i))))
18162 /* The expression is not value-dependent. */
18166 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
18167 [temp.dep.expr]. */
18170 type_dependent_expression_p (tree expression)
18172 if (!processing_template_decl)
18175 if (expression == error_mark_node)
18178 /* An unresolved name is always dependent. */
18179 if (TREE_CODE (expression) == IDENTIFIER_NODE
18180 || TREE_CODE (expression) == USING_DECL)
18183 /* Some expression forms are never type-dependent. */
18184 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
18185 || TREE_CODE (expression) == SIZEOF_EXPR
18186 || TREE_CODE (expression) == ALIGNOF_EXPR
18187 || TREE_CODE (expression) == AT_ENCODE_EXPR
18188 || TREE_CODE (expression) == NOEXCEPT_EXPR
18189 || TREE_CODE (expression) == TRAIT_EXPR
18190 || TREE_CODE (expression) == TYPEID_EXPR
18191 || TREE_CODE (expression) == DELETE_EXPR
18192 || TREE_CODE (expression) == VEC_DELETE_EXPR
18193 || TREE_CODE (expression) == THROW_EXPR)
18196 /* The types of these expressions depends only on the type to which
18197 the cast occurs. */
18198 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
18199 || TREE_CODE (expression) == STATIC_CAST_EXPR
18200 || TREE_CODE (expression) == CONST_CAST_EXPR
18201 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
18202 || TREE_CODE (expression) == CAST_EXPR)
18203 return dependent_type_p (TREE_TYPE (expression));
18205 /* The types of these expressions depends only on the type created
18206 by the expression. */
18207 if (TREE_CODE (expression) == NEW_EXPR
18208 || TREE_CODE (expression) == VEC_NEW_EXPR)
18210 /* For NEW_EXPR tree nodes created inside a template, either
18211 the object type itself or a TREE_LIST may appear as the
18213 tree type = TREE_OPERAND (expression, 1);
18214 if (TREE_CODE (type) == TREE_LIST)
18215 /* This is an array type. We need to check array dimensions
18217 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
18218 || value_dependent_expression_p
18219 (TREE_OPERAND (TREE_VALUE (type), 1));
18221 return dependent_type_p (type);
18224 if (TREE_CODE (expression) == SCOPE_REF)
18226 tree scope = TREE_OPERAND (expression, 0);
18227 tree name = TREE_OPERAND (expression, 1);
18229 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
18230 contains an identifier associated by name lookup with one or more
18231 declarations declared with a dependent type, or...a
18232 nested-name-specifier or qualified-id that names a member of an
18233 unknown specialization. */
18234 return (type_dependent_expression_p (name)
18235 || dependent_scope_p (scope));
18238 if (TREE_CODE (expression) == FUNCTION_DECL
18239 && DECL_LANG_SPECIFIC (expression)
18240 && DECL_TEMPLATE_INFO (expression)
18241 && (any_dependent_template_arguments_p
18242 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
18245 if (TREE_CODE (expression) == TEMPLATE_DECL
18246 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
18249 if (TREE_CODE (expression) == STMT_EXPR)
18250 expression = stmt_expr_value_expr (expression);
18252 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
18257 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
18259 if (type_dependent_expression_p (elt))
18265 /* A static data member of the current instantiation with incomplete
18266 array type is type-dependent, as the definition and specializations
18267 can have different bounds. */
18268 if (TREE_CODE (expression) == VAR_DECL
18269 && DECL_CLASS_SCOPE_P (expression)
18270 && dependent_type_p (DECL_CONTEXT (expression))
18271 && VAR_HAD_UNKNOWN_BOUND (expression))
18274 if (TREE_TYPE (expression) == unknown_type_node)
18276 if (TREE_CODE (expression) == ADDR_EXPR)
18277 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
18278 if (TREE_CODE (expression) == COMPONENT_REF
18279 || TREE_CODE (expression) == OFFSET_REF)
18281 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
18283 expression = TREE_OPERAND (expression, 1);
18284 if (TREE_CODE (expression) == IDENTIFIER_NODE)
18287 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
18288 if (TREE_CODE (expression) == SCOPE_REF)
18291 if (TREE_CODE (expression) == BASELINK)
18292 expression = BASELINK_FUNCTIONS (expression);
18294 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
18296 if (any_dependent_template_arguments_p
18297 (TREE_OPERAND (expression, 1)))
18299 expression = TREE_OPERAND (expression, 0);
18301 gcc_assert (TREE_CODE (expression) == OVERLOAD
18302 || TREE_CODE (expression) == FUNCTION_DECL);
18306 if (type_dependent_expression_p (OVL_CURRENT (expression)))
18308 expression = OVL_NEXT (expression);
18313 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
18315 return (dependent_type_p (TREE_TYPE (expression)));
18318 /* Like type_dependent_expression_p, but it also works while not processing
18319 a template definition, i.e. during substitution or mangling. */
18322 type_dependent_expression_p_push (tree expr)
18325 ++processing_template_decl;
18326 b = type_dependent_expression_p (expr);
18327 --processing_template_decl;
18331 /* Returns TRUE if ARGS contains a type-dependent expression. */
18334 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
18339 FOR_EACH_VEC_ELT (tree, args, i, arg)
18341 if (type_dependent_expression_p (arg))
18347 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
18348 expressions) contains any value-dependent expressions. */
18351 any_value_dependent_elements_p (const_tree list)
18353 for (; list; list = TREE_CHAIN (list))
18354 if (value_dependent_expression_p (TREE_VALUE (list)))
18360 /* Returns TRUE if the ARG (a template argument) is dependent. */
18363 dependent_template_arg_p (tree arg)
18365 if (!processing_template_decl)
18368 /* Assume a template argument that was wrongly written by the user
18369 is dependent. This is consistent with what
18370 any_dependent_template_arguments_p [that calls this function]
18372 if (arg == error_mark_node)
18375 if (TREE_CODE (arg) == TEMPLATE_DECL
18376 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18377 return dependent_template_p (arg);
18378 else if (ARGUMENT_PACK_P (arg))
18380 tree args = ARGUMENT_PACK_ARGS (arg);
18381 int i, len = TREE_VEC_LENGTH (args);
18382 for (i = 0; i < len; ++i)
18384 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18390 else if (TYPE_P (arg))
18391 return dependent_type_p (arg);
18393 return (type_dependent_expression_p (arg)
18394 || value_dependent_expression_p (arg));
18397 /* Returns true if ARGS (a collection of template arguments) contains
18398 any types that require structural equality testing. */
18401 any_template_arguments_need_structural_equality_p (tree args)
18408 if (args == error_mark_node)
18411 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18413 tree level = TMPL_ARGS_LEVEL (args, i + 1);
18414 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18416 tree arg = TREE_VEC_ELT (level, j);
18417 tree packed_args = NULL_TREE;
18420 if (ARGUMENT_PACK_P (arg))
18422 /* Look inside the argument pack. */
18423 packed_args = ARGUMENT_PACK_ARGS (arg);
18424 len = TREE_VEC_LENGTH (packed_args);
18427 for (k = 0; k < len; ++k)
18430 arg = TREE_VEC_ELT (packed_args, k);
18432 if (error_operand_p (arg))
18434 else if (TREE_CODE (arg) == TEMPLATE_DECL
18435 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
18437 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
18439 else if (!TYPE_P (arg) && TREE_TYPE (arg)
18440 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
18449 /* Returns true if ARGS (a collection of template arguments) contains
18450 any dependent arguments. */
18453 any_dependent_template_arguments_p (const_tree args)
18460 if (args == error_mark_node)
18463 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
18465 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
18466 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
18467 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
18474 /* Returns TRUE if the template TMPL is dependent. */
18477 dependent_template_p (tree tmpl)
18479 if (TREE_CODE (tmpl) == OVERLOAD)
18483 if (dependent_template_p (OVL_FUNCTION (tmpl)))
18485 tmpl = OVL_CHAIN (tmpl);
18490 /* Template template parameters are dependent. */
18491 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
18492 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
18494 /* So are names that have not been looked up. */
18495 if (TREE_CODE (tmpl) == SCOPE_REF
18496 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
18498 /* So are member templates of dependent classes. */
18499 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
18500 return dependent_type_p (DECL_CONTEXT (tmpl));
18504 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
18507 dependent_template_id_p (tree tmpl, tree args)
18509 return (dependent_template_p (tmpl)
18510 || any_dependent_template_arguments_p (args));
18513 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
18517 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
18521 if (!processing_template_decl)
18524 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
18526 tree decl = TREE_VEC_ELT (declv, i);
18527 tree init = TREE_VEC_ELT (initv, i);
18528 tree cond = TREE_VEC_ELT (condv, i);
18529 tree incr = TREE_VEC_ELT (incrv, i);
18531 if (type_dependent_expression_p (decl))
18534 if (init && type_dependent_expression_p (init))
18537 if (type_dependent_expression_p (cond))
18540 if (COMPARISON_CLASS_P (cond)
18541 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
18542 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
18545 if (TREE_CODE (incr) == MODOP_EXPR)
18547 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
18548 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
18551 else if (type_dependent_expression_p (incr))
18553 else if (TREE_CODE (incr) == MODIFY_EXPR)
18555 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
18557 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
18559 tree t = TREE_OPERAND (incr, 1);
18560 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
18561 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
18570 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
18571 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
18572 no such TYPE can be found. Note that this function peers inside
18573 uninstantiated templates and therefore should be used only in
18574 extremely limited situations. ONLY_CURRENT_P restricts this
18575 peering to the currently open classes hierarchy (which is required
18576 when comparing types). */
18579 resolve_typename_type (tree type, bool only_current_p)
18588 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
18590 scope = TYPE_CONTEXT (type);
18591 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
18592 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
18593 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
18594 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
18595 identifier of the TYPENAME_TYPE anymore.
18596 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
18597 TYPENAME_TYPE instead, we avoid messing up with a possible
18598 typedef variant case. */
18599 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
18601 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
18602 it first before we can figure out what NAME refers to. */
18603 if (TREE_CODE (scope) == TYPENAME_TYPE)
18604 scope = resolve_typename_type (scope, only_current_p);
18605 /* If we don't know what SCOPE refers to, then we cannot resolve the
18607 if (TREE_CODE (scope) == TYPENAME_TYPE)
18609 /* If the SCOPE is a template type parameter, we have no way of
18610 resolving the name. */
18611 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
18613 /* If the SCOPE is not the current instantiation, there's no reason
18614 to look inside it. */
18615 if (only_current_p && !currently_open_class (scope))
18617 /* If this is a typedef, we don't want to look inside (c++/11987). */
18618 if (typedef_variant_p (type))
18620 /* If SCOPE isn't the template itself, it will not have a valid
18621 TYPE_FIELDS list. */
18622 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
18623 /* scope is either the template itself or a compatible instantiation
18624 like X<T>, so look up the name in the original template. */
18625 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
18627 /* scope is a partial instantiation, so we can't do the lookup or we
18628 will lose the template arguments. */
18630 /* Enter the SCOPE so that name lookup will be resolved as if we
18631 were in the class definition. In particular, SCOPE will no
18632 longer be considered a dependent type. */
18633 pushed_scope = push_scope (scope);
18634 /* Look up the declaration. */
18635 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
18637 result = NULL_TREE;
18639 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
18640 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
18643 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
18644 && TREE_CODE (decl) == TYPE_DECL)
18646 result = TREE_TYPE (decl);
18647 if (result == error_mark_node)
18648 result = NULL_TREE;
18650 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
18651 && DECL_CLASS_TEMPLATE_P (decl))
18655 /* Obtain the template and the arguments. */
18656 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
18657 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
18658 /* Instantiate the template. */
18659 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
18660 /*entering_scope=*/0,
18661 tf_error | tf_user);
18662 if (result == error_mark_node)
18663 result = NULL_TREE;
18666 /* Leave the SCOPE. */
18668 pop_scope (pushed_scope);
18670 /* If we failed to resolve it, return the original typename. */
18674 /* If lookup found a typename type, resolve that too. */
18675 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
18677 /* Ill-formed programs can cause infinite recursion here, so we
18678 must catch that. */
18679 TYPENAME_IS_RESOLVING_P (type) = 1;
18680 result = resolve_typename_type (result, only_current_p);
18681 TYPENAME_IS_RESOLVING_P (type) = 0;
18684 /* Qualify the resulting type. */
18685 quals = cp_type_quals (type);
18687 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
18692 /* EXPR is an expression which is not type-dependent. Return a proxy
18693 for EXPR that can be used to compute the types of larger
18694 expressions containing EXPR. */
18697 build_non_dependent_expr (tree expr)
18701 /* Preserve null pointer constants so that the type of things like
18702 "p == 0" where "p" is a pointer can be determined. */
18703 if (null_ptr_cst_p (expr))
18705 /* Preserve OVERLOADs; the functions must be available to resolve
18708 if (TREE_CODE (inner_expr) == STMT_EXPR)
18709 inner_expr = stmt_expr_value_expr (inner_expr);
18710 if (TREE_CODE (inner_expr) == ADDR_EXPR)
18711 inner_expr = TREE_OPERAND (inner_expr, 0);
18712 if (TREE_CODE (inner_expr) == COMPONENT_REF)
18713 inner_expr = TREE_OPERAND (inner_expr, 1);
18714 if (is_overloaded_fn (inner_expr)
18715 || TREE_CODE (inner_expr) == OFFSET_REF)
18717 /* There is no need to return a proxy for a variable. */
18718 if (TREE_CODE (expr) == VAR_DECL)
18720 /* Preserve string constants; conversions from string constants to
18721 "char *" are allowed, even though normally a "const char *"
18722 cannot be used to initialize a "char *". */
18723 if (TREE_CODE (expr) == STRING_CST)
18725 /* Preserve arithmetic constants, as an optimization -- there is no
18726 reason to create a new node. */
18727 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
18729 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
18730 There is at least one place where we want to know that a
18731 particular expression is a throw-expression: when checking a ?:
18732 expression, there are special rules if the second or third
18733 argument is a throw-expression. */
18734 if (TREE_CODE (expr) == THROW_EXPR)
18737 if (TREE_CODE (expr) == COND_EXPR)
18738 return build3 (COND_EXPR,
18740 TREE_OPERAND (expr, 0),
18741 (TREE_OPERAND (expr, 1)
18742 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
18743 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
18744 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
18745 if (TREE_CODE (expr) == COMPOUND_EXPR
18746 && !COMPOUND_EXPR_OVERLOADED (expr))
18747 return build2 (COMPOUND_EXPR,
18749 TREE_OPERAND (expr, 0),
18750 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
18752 /* If the type is unknown, it can't really be non-dependent */
18753 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
18755 /* Otherwise, build a NON_DEPENDENT_EXPR.
18757 REFERENCE_TYPEs are not stripped for expressions in templates
18758 because doing so would play havoc with mangling. Consider, for
18761 template <typename T> void f<T& g>() { g(); }
18763 In the body of "f", the expression for "g" will have
18764 REFERENCE_TYPE, even though the standard says that it should
18765 not. The reason is that we must preserve the syntactic form of
18766 the expression so that mangling (say) "f<g>" inside the body of
18767 "f" works out correctly. Therefore, the REFERENCE_TYPE is
18769 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
18772 /* ARGS is a vector of expressions as arguments to a function call.
18773 Replace the arguments with equivalent non-dependent expressions.
18774 This modifies ARGS in place. */
18777 make_args_non_dependent (VEC(tree,gc) *args)
18782 FOR_EACH_VEC_ELT (tree, args, ix, arg)
18784 tree newarg = build_non_dependent_expr (arg);
18786 VEC_replace (tree, args, ix, newarg);
18790 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
18791 with a level one deeper than the actual template parms. */
18796 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
18797 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
18798 TYPE_DECL, get_identifier ("auto"), au);
18799 TYPE_STUB_DECL (au) = TYPE_NAME (au);
18800 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
18801 (0, processing_template_decl + 1, processing_template_decl + 1,
18802 0, TYPE_NAME (au), NULL_TREE);
18803 TYPE_CANONICAL (au) = canonical_type_parameter (au);
18804 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
18805 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
18810 /* Given type ARG, return std::initializer_list<ARG>. */
18815 tree std_init_list = namespace_binding
18816 (get_identifier ("initializer_list"), std_node);
18818 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
18820 error ("deducing from brace-enclosed initializer list requires "
18821 "#include <initializer_list>");
18822 return error_mark_node;
18824 argvec = make_tree_vec (1);
18825 TREE_VEC_ELT (argvec, 0) = arg;
18826 return lookup_template_class (std_init_list, argvec, NULL_TREE,
18827 NULL_TREE, 0, tf_warning_or_error);
18830 /* Replace auto in TYPE with std::initializer_list<auto>. */
18833 listify_autos (tree type, tree auto_node)
18835 tree init_auto = listify (auto_node);
18836 tree argvec = make_tree_vec (1);
18837 TREE_VEC_ELT (argvec, 0) = init_auto;
18838 if (processing_template_decl)
18839 argvec = add_to_template_args (current_template_args (), argvec);
18840 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18843 /* walk_tree helper for do_auto_deduction. */
18846 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
18849 /* Is this a variable with the type we're looking for? */
18851 && TREE_TYPE (*tp) == type)
18857 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
18858 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
18861 do_auto_deduction (tree type, tree init, tree auto_node)
18863 tree parms, tparms, targs;
18868 /* The name of the object being declared shall not appear in the
18869 initializer expression. */
18870 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
18873 error ("variable %q#D with %<auto%> type used in its own "
18874 "initializer", decl);
18875 return error_mark_node;
18878 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
18879 with either a new invented type template parameter U or, if the
18880 initializer is a braced-init-list (8.5.4), with
18881 std::initializer_list<U>. */
18882 if (BRACE_ENCLOSED_INITIALIZER_P (init))
18883 type = listify_autos (type, auto_node);
18885 parms = build_tree_list (NULL_TREE, type);
18887 tparms = make_tree_vec (1);
18888 targs = make_tree_vec (1);
18889 TREE_VEC_ELT (tparms, 0)
18890 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
18891 val = type_unification_real (tparms, targs, parms, args, 1, 0,
18892 DEDUCE_CALL, LOOKUP_NORMAL);
18895 error ("unable to deduce %qT from %qE", type, init);
18896 return error_mark_node;
18899 /* If the list of declarators contains more than one declarator, the type
18900 of each declared variable is determined as described above. If the
18901 type deduced for the template parameter U is not the same in each
18902 deduction, the program is ill-formed. */
18903 if (TREE_TYPE (auto_node)
18904 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
18906 error ("inconsistent deduction for %qT: %qT and then %qT",
18907 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
18908 return error_mark_node;
18910 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
18912 if (processing_template_decl)
18913 targs = add_to_template_args (current_template_args (), targs);
18914 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
18917 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
18921 splice_late_return_type (tree type, tree late_return_type)
18925 if (late_return_type == NULL_TREE)
18927 argvec = make_tree_vec (1);
18928 TREE_VEC_ELT (argvec, 0) = late_return_type;
18929 if (processing_template_decl)
18930 argvec = add_to_template_args (current_template_args (), argvec);
18931 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18934 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
18937 is_auto (const_tree type)
18939 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18940 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
18946 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
18947 appear as a type-specifier for the declaration in question, we don't
18948 have to look through the whole type. */
18951 type_uses_auto (tree type)
18953 enum tree_code code;
18954 if (is_auto (type))
18957 code = TREE_CODE (type);
18959 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18960 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18961 || code == METHOD_TYPE || code == ARRAY_TYPE)
18962 return type_uses_auto (TREE_TYPE (type));
18964 if (TYPE_PTRMEMFUNC_P (type))
18965 return type_uses_auto (TREE_TYPE (TREE_TYPE
18966 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18971 /* For a given template T, return the vector of typedefs referenced
18972 in T for which access check is needed at T instantiation time.
18973 T is either a FUNCTION_DECL or a RECORD_TYPE.
18974 Those typedefs were added to T by the function
18975 append_type_to_template_for_access_check. */
18977 VEC(qualified_typedef_usage_t,gc)*
18978 get_types_needing_access_check (tree t)
18981 VEC(qualified_typedef_usage_t,gc) *result = NULL;
18983 if (!t || t == error_mark_node)
18986 if (!(ti = get_template_info (t)))
18989 if (CLASS_TYPE_P (t)
18990 || TREE_CODE (t) == FUNCTION_DECL)
18992 if (!TI_TEMPLATE (ti))
18995 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19001 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19002 tied to T. That list of typedefs will be access checked at
19003 T instantiation time.
19004 T is either a FUNCTION_DECL or a RECORD_TYPE.
19005 TYPE_DECL is a TYPE_DECL node representing a typedef.
19006 SCOPE is the scope through which TYPE_DECL is accessed.
19007 LOCATION is the location of the usage point of TYPE_DECL.
19009 This function is a subroutine of
19010 append_type_to_template_for_access_check. */
19013 append_type_to_template_for_access_check_1 (tree t,
19016 location_t location)
19018 qualified_typedef_usage_t typedef_usage;
19021 if (!t || t == error_mark_node)
19024 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19025 || CLASS_TYPE_P (t))
19027 && TREE_CODE (type_decl) == TYPE_DECL
19030 if (!(ti = get_template_info (t)))
19033 gcc_assert (TI_TEMPLATE (ti));
19035 typedef_usage.typedef_decl = type_decl;
19036 typedef_usage.context = scope;
19037 typedef_usage.locus = location;
19039 VEC_safe_push (qualified_typedef_usage_t, gc,
19040 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
19044 /* Append TYPE_DECL to the template TEMPL.
19045 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
19046 At TEMPL instanciation time, TYPE_DECL will be checked to see
19047 if it can be accessed through SCOPE.
19048 LOCATION is the location of the usage point of TYPE_DECL.
19050 e.g. consider the following code snippet:
19057 template<class U> struct S
19059 C::myint mi; // <-- usage point of the typedef C::myint
19064 At S<char> instantiation time, we need to check the access of C::myint
19065 In other words, we need to check the access of the myint typedef through
19066 the C scope. For that purpose, this function will add the myint typedef
19067 and the scope C through which its being accessed to a list of typedefs
19068 tied to the template S. That list will be walked at template instantiation
19069 time and access check performed on each typedefs it contains.
19070 Note that this particular code snippet should yield an error because
19071 myint is private to C. */
19074 append_type_to_template_for_access_check (tree templ,
19077 location_t location)
19079 qualified_typedef_usage_t *iter;
19082 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
19084 /* Make sure we don't append the type to the template twice. */
19085 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
19086 get_types_needing_access_check (templ),
19088 if (iter->typedef_decl == type_decl && scope == iter->context)
19091 append_type_to_template_for_access_check_1 (templ, type_decl,
19095 /* Set up the hash tables for template instantiations. */
19098 init_template_processing (void)
19100 decl_specializations = htab_create_ggc (37,
19101 hash_specialization,
19102 eq_specializations,
19104 type_specializations = htab_create_ggc (37,
19105 hash_specialization,
19106 eq_specializations,
19110 /* Print stats about the template hash tables for -fstats. */
19113 print_template_statistics (void)
19115 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
19116 "%f collisions\n", (long) htab_size (decl_specializations),
19117 (long) htab_elements (decl_specializations),
19118 htab_collisions (decl_specializations));
19119 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
19120 "%f collisions\n", (long) htab_size (type_specializations),
19121 (long) htab_elements (type_specializations),
19122 htab_collisions (type_specializations));
19125 #include "gt-cp-pt.h"