1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 enum template_base_result {
114 tbr_ambiguous_baseclass,
118 static void push_access_scope (tree);
119 static void pop_access_scope (tree);
120 static void push_deduction_access_scope (tree);
121 static void pop_deduction_access_scope (tree);
122 static bool resolve_overloaded_unification (tree, tree, tree, tree,
123 unification_kind_t, int,
125 static int try_one_overload (tree, tree, tree, tree, tree,
126 unification_kind_t, int, bool, bool);
127 static int unify (tree, tree, tree, tree, int, bool);
128 static void add_pending_template (tree);
129 static tree reopen_tinst_level (struct tinst_level *);
130 static tree tsubst_initializer_list (tree, tree);
131 static tree get_class_bindings (tree, tree, tree);
132 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
134 static void tsubst_enum (tree, tree, tree);
135 static tree add_to_template_args (tree, tree);
136 static tree add_outermost_template_args (tree, tree);
137 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
138 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
140 static int type_unification_real (tree, tree, tree, const tree *,
141 unsigned int, int, unification_kind_t, int,
143 static void note_template_header (int);
144 static tree convert_nontype_argument_function (tree, tree);
145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
146 static tree convert_template_argument (tree, tree, tree,
147 tsubst_flags_t, int, tree);
148 static int for_each_template_parm (tree, tree_fn_t, void*,
149 struct pointer_set_t*, bool);
150 static tree expand_template_argument_pack (tree);
151 static tree build_template_parm_index (int, int, int, int, tree, tree);
152 static bool inline_needs_template_parms (tree);
153 static void push_inline_template_parms_recursive (tree, int);
154 static tree retrieve_local_specialization (tree);
155 static void register_local_specialization (tree, tree);
156 static hashval_t hash_specialization (const void *p);
157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
158 static int mark_template_parm (tree, void *);
159 static int template_parm_this_level_p (tree, void *);
160 static tree tsubst_friend_function (tree, tree);
161 static tree tsubst_friend_class (tree, tree);
162 static int can_complete_type_without_circularity (tree);
163 static tree get_bindings (tree, tree, tree, bool);
164 static int template_decl_level (tree);
165 static int check_cv_quals_for_unify (int, tree, tree);
166 static void template_parm_level_and_index (tree, int*, int*);
167 static int unify_pack_expansion (tree, tree, tree,
168 tree, int, bool, bool, bool);
169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
172 static void regenerate_decl_from_template (tree, tree);
173 static tree most_specialized_class (tree, tree, tsubst_flags_t);
174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
175 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
177 static bool check_specialization_scope (void);
178 static tree process_partial_specialization (tree);
179 static void set_current_access_from_decl (tree);
180 static enum template_base_result get_template_base (tree, tree, tree, tree,
182 static tree try_class_unification (tree, tree, tree, tree, bool);
183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
185 static bool template_template_parm_bindings_ok_p (tree, tree);
186 static int template_args_equal (tree, tree);
187 static void tsubst_default_arguments (tree);
188 static tree for_each_template_parm_r (tree *, int *, void *);
189 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
190 static void copy_default_args_to_explicit_spec (tree);
191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
192 static int eq_local_specializations (const void *, const void *);
193 static bool dependent_template_arg_p (tree);
194 static bool any_template_arguments_need_structural_equality_p (tree);
195 static bool dependent_type_p_r (tree);
196 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
197 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
198 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
199 static tree tsubst_decl (tree, tree, tsubst_flags_t);
200 static void perform_typedefs_access_check (tree tmpl, tree targs);
201 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
203 static tree listify (tree);
204 static tree listify_autos (tree, tree);
205 static tree template_parm_to_arg (tree t);
206 static tree current_template_args (void);
207 static tree fixup_template_type_parm_type (tree, int);
208 static tree fixup_template_parm_index (tree, tree, int);
209 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
211 /* Make the current scope suitable for access checking when we are
212 processing T. T can be FUNCTION_DECL for instantiated function
213 template, or VAR_DECL for static member variable (need by
214 instantiate_decl). */
217 push_access_scope (tree t)
219 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
220 || TREE_CODE (t) == VAR_DECL);
222 if (DECL_FRIEND_CONTEXT (t))
223 push_nested_class (DECL_FRIEND_CONTEXT (t));
224 else if (DECL_CLASS_SCOPE_P (t))
225 push_nested_class (DECL_CONTEXT (t));
227 push_to_top_level ();
229 if (TREE_CODE (t) == FUNCTION_DECL)
231 saved_access_scope = tree_cons
232 (NULL_TREE, current_function_decl, saved_access_scope);
233 current_function_decl = t;
237 /* Restore the scope set up by push_access_scope. T is the node we
241 pop_access_scope (tree t)
243 if (TREE_CODE (t) == FUNCTION_DECL)
245 current_function_decl = TREE_VALUE (saved_access_scope);
246 saved_access_scope = TREE_CHAIN (saved_access_scope);
249 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
252 pop_from_top_level ();
255 /* Do any processing required when DECL (a member template
256 declaration) is finished. Returns the TEMPLATE_DECL corresponding
257 to DECL, unless it is a specialization, in which case the DECL
258 itself is returned. */
261 finish_member_template_decl (tree decl)
263 if (decl == error_mark_node)
264 return error_mark_node;
266 gcc_assert (DECL_P (decl));
268 if (TREE_CODE (decl) == TYPE_DECL)
272 type = TREE_TYPE (decl);
273 if (type == error_mark_node)
274 return error_mark_node;
275 if (MAYBE_CLASS_TYPE_P (type)
276 && CLASSTYPE_TEMPLATE_INFO (type)
277 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
279 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
280 check_member_template (tmpl);
285 else if (TREE_CODE (decl) == FIELD_DECL)
286 error ("data member %qD cannot be a member template", decl);
287 else if (DECL_TEMPLATE_INFO (decl))
289 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
291 check_member_template (DECL_TI_TEMPLATE (decl));
292 return DECL_TI_TEMPLATE (decl);
298 error ("invalid member template declaration %qD", decl);
300 return error_mark_node;
303 /* Create a template info node. */
306 build_template_info (tree template_decl, tree template_args)
308 tree result = make_node (TEMPLATE_INFO);
309 TI_TEMPLATE (result) = template_decl;
310 TI_ARGS (result) = template_args;
314 /* Return the template info node corresponding to T, whatever T is. */
317 get_template_info (const_tree t)
319 tree tinfo = NULL_TREE;
321 if (!t || t == error_mark_node)
324 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
325 tinfo = DECL_TEMPLATE_INFO (t);
327 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
330 if (TAGGED_TYPE_P (t))
331 tinfo = TYPE_TEMPLATE_INFO (t);
332 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
333 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
338 /* Returns the template nesting level of the indicated class TYPE.
348 A<T>::B<U> has depth two, while A<T> has depth one.
349 Both A<T>::B<int> and A<int>::B<U> have depth one, if
350 they are instantiations, not specializations.
352 This function is guaranteed to return 0 if passed NULL_TREE so
353 that, for example, `template_class_depth (current_class_type)' is
357 template_class_depth (tree type)
362 type && TREE_CODE (type) != NAMESPACE_DECL;
363 type = (TREE_CODE (type) == FUNCTION_DECL)
364 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
366 tree tinfo = get_template_info (type);
368 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
369 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
376 /* Subroutine of maybe_begin_member_template_processing.
377 Returns true if processing DECL needs us to push template parms. */
380 inline_needs_template_parms (tree decl)
382 if (! DECL_TEMPLATE_INFO (decl))
385 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
386 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
389 /* Subroutine of maybe_begin_member_template_processing.
390 Push the template parms in PARMS, starting from LEVELS steps into the
391 chain, and ending at the beginning, since template parms are listed
395 push_inline_template_parms_recursive (tree parmlist, int levels)
397 tree parms = TREE_VALUE (parmlist);
401 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
403 ++processing_template_decl;
404 current_template_parms
405 = tree_cons (size_int (processing_template_decl),
406 parms, current_template_parms);
407 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
409 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
411 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
413 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
415 if (parm == error_mark_node)
418 gcc_assert (DECL_P (parm));
420 switch (TREE_CODE (parm))
429 /* Make a CONST_DECL as is done in process_template_parm.
430 It is ugly that we recreate this here; the original
431 version built in process_template_parm is no longer
433 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
434 CONST_DECL, DECL_NAME (parm),
436 DECL_ARTIFICIAL (decl) = 1;
437 TREE_CONSTANT (decl) = 1;
438 TREE_READONLY (decl) = 1;
439 DECL_INITIAL (decl) = DECL_INITIAL (parm);
440 SET_DECL_TEMPLATE_PARM_P (decl);
451 /* Restore the template parameter context for a member template or
452 a friend template defined in a class definition. */
455 maybe_begin_member_template_processing (tree decl)
460 if (inline_needs_template_parms (decl))
462 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
463 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
465 if (DECL_TEMPLATE_SPECIALIZATION (decl))
468 parms = TREE_CHAIN (parms);
471 push_inline_template_parms_recursive (parms, levels);
474 /* Remember how many levels of template parameters we pushed so that
475 we can pop them later. */
476 VEC_safe_push (int, heap, inline_parm_levels, levels);
479 /* Undo the effects of maybe_begin_member_template_processing. */
482 maybe_end_member_template_processing (void)
487 if (VEC_length (int, inline_parm_levels) == 0)
490 last = VEC_pop (int, inline_parm_levels);
491 for (i = 0; i < last; ++i)
493 --processing_template_decl;
494 current_template_parms = TREE_CHAIN (current_template_parms);
499 /* Return a new template argument vector which contains all of ARGS,
500 but has as its innermost set of arguments the EXTRA_ARGS. */
503 add_to_template_args (tree args, tree extra_args)
510 if (args == NULL_TREE || extra_args == error_mark_node)
513 extra_depth = TMPL_ARGS_DEPTH (extra_args);
514 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
516 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
517 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
519 for (j = 1; j <= extra_depth; ++j, ++i)
520 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
525 /* Like add_to_template_args, but only the outermost ARGS are added to
526 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
527 (EXTRA_ARGS) levels are added. This function is used to combine
528 the template arguments from a partial instantiation with the
529 template arguments used to attain the full instantiation from the
530 partial instantiation. */
533 add_outermost_template_args (tree args, tree extra_args)
537 /* If there are more levels of EXTRA_ARGS than there are ARGS,
538 something very fishy is going on. */
539 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
541 /* If *all* the new arguments will be the EXTRA_ARGS, just return
543 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
546 /* For the moment, we make ARGS look like it contains fewer levels. */
547 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
549 new_args = add_to_template_args (args, extra_args);
551 /* Now, we restore ARGS to its full dimensions. */
552 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
557 /* Return the N levels of innermost template arguments from the ARGS. */
560 get_innermost_template_args (tree args, int n)
568 /* If N is 1, just return the innermost set of template arguments. */
570 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
572 /* If we're not removing anything, just return the arguments we were
574 extra_levels = TMPL_ARGS_DEPTH (args) - n;
575 gcc_assert (extra_levels >= 0);
576 if (extra_levels == 0)
579 /* Make a new set of arguments, not containing the outer arguments. */
580 new_args = make_tree_vec (n);
581 for (i = 1; i <= n; ++i)
582 SET_TMPL_ARGS_LEVEL (new_args, i,
583 TMPL_ARGS_LEVEL (args, i + extra_levels));
588 /* The inverse of get_innermost_template_args: Return all but the innermost
589 EXTRA_LEVELS levels of template arguments from the ARGS. */
592 strip_innermost_template_args (tree args, int extra_levels)
595 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
600 /* If N is 1, just return the outermost set of template arguments. */
602 return TMPL_ARGS_LEVEL (args, 1);
604 /* If we're not removing anything, just return the arguments we were
606 gcc_assert (extra_levels >= 0);
607 if (extra_levels == 0)
610 /* Make a new set of arguments, not containing the inner arguments. */
611 new_args = make_tree_vec (n);
612 for (i = 1; i <= n; ++i)
613 SET_TMPL_ARGS_LEVEL (new_args, i,
614 TMPL_ARGS_LEVEL (args, i));
619 /* We've got a template header coming up; push to a new level for storing
623 begin_template_parm_list (void)
625 /* We use a non-tag-transparent scope here, which causes pushtag to
626 put tags in this scope, rather than in the enclosing class or
627 namespace scope. This is the right thing, since we want
628 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
629 global template class, push_template_decl handles putting the
630 TEMPLATE_DECL into top-level scope. For a nested template class,
633 template <class T> struct S1 {
634 template <class T> struct S2 {};
637 pushtag contains special code to call pushdecl_with_scope on the
638 TEMPLATE_DECL for S2. */
639 begin_scope (sk_template_parms, NULL);
640 ++processing_template_decl;
641 ++processing_template_parmlist;
642 note_template_header (0);
645 /* This routine is called when a specialization is declared. If it is
646 invalid to declare a specialization here, an error is reported and
647 false is returned, otherwise this routine will return true. */
650 check_specialization_scope (void)
652 tree scope = current_scope ();
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template
663 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
665 error ("explicit specialization in non-namespace scope %qD", scope);
671 In an explicit specialization declaration for a member of a class
672 template or a member template that appears in namespace scope,
673 the member template and some of its enclosing class templates may
674 remain unspecialized, except that the declaration shall not
675 explicitly specialize a class member template if its enclosing
676 class templates are not explicitly specialized as well. */
677 if (current_template_parms)
679 error ("enclosing class templates are not explicitly specialized");
686 /* We've just seen template <>. */
689 begin_specialization (void)
691 begin_scope (sk_template_spec, NULL);
692 note_template_header (1);
693 return check_specialization_scope ();
696 /* Called at then end of processing a declaration preceded by
700 end_specialization (void)
703 reset_specialization ();
706 /* Any template <>'s that we have seen thus far are not referring to a
707 function specialization. */
710 reset_specialization (void)
712 processing_specialization = 0;
713 template_header_count = 0;
716 /* We've just seen a template header. If SPECIALIZATION is nonzero,
717 it was of the form template <>. */
720 note_template_header (int specialization)
722 processing_specialization = specialization;
723 template_header_count++;
726 /* We're beginning an explicit instantiation. */
729 begin_explicit_instantiation (void)
731 gcc_assert (!processing_explicit_instantiation);
732 processing_explicit_instantiation = true;
737 end_explicit_instantiation (void)
739 gcc_assert (processing_explicit_instantiation);
740 processing_explicit_instantiation = false;
743 /* An explicit specialization or partial specialization TMPL is being
744 declared. Check that the namespace in which the specialization is
745 occurring is permissible. Returns false iff it is invalid to
746 specialize TMPL in the current namespace. */
749 check_specialization_namespace (tree tmpl)
751 tree tpl_ns = decl_namespace_context (tmpl);
755 An explicit specialization shall be declared in the namespace of
756 which the template is a member, or, for member templates, in the
757 namespace of which the enclosing class or enclosing class
758 template is a member. An explicit specialization of a member
759 function, member class or static data member of a class template
760 shall be declared in the namespace of which the class template is
762 if (current_scope() != DECL_CONTEXT (tmpl)
763 && !at_namespace_scope_p ())
765 error ("specialization of %qD must appear at namespace scope", tmpl);
768 if (is_associated_namespace (current_namespace, tpl_ns))
769 /* Same or super-using namespace. */
773 permerror (input_location, "specialization of %qD in different namespace", tmpl);
774 permerror (input_location, " from definition of %q+#D", tmpl);
779 /* SPEC is an explicit instantiation. Check that it is valid to
780 perform this explicit instantiation in the current namespace. */
783 check_explicit_instantiation_namespace (tree spec)
787 /* DR 275: An explicit instantiation shall appear in an enclosing
788 namespace of its template. */
789 ns = decl_namespace_context (spec);
790 if (!is_ancestor (current_namespace, ns))
791 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
792 "(which does not enclose namespace %qD)",
793 spec, current_namespace, ns);
796 /* The TYPE is being declared. If it is a template type, that means it
797 is a partial specialization. Do appropriate error-checking. */
800 maybe_process_partial_specialization (tree type)
804 if (type == error_mark_node)
805 return error_mark_node;
807 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
809 error ("name of class shadows template template parameter %qD",
811 return error_mark_node;
814 context = TYPE_CONTEXT (type);
816 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
818 /* This is for ordinary explicit specialization and partial
819 specialization of a template class such as:
821 template <> class C<int>;
825 template <class T> class C<T*>;
827 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
829 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
830 && !COMPLETE_TYPE_P (type))
832 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
833 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
834 if (processing_template_decl)
836 if (push_template_decl (TYPE_MAIN_DECL (type))
838 return error_mark_node;
841 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
842 error ("specialization of %qT after instantiation", type);
844 else if (CLASS_TYPE_P (type)
845 && !CLASSTYPE_USE_TEMPLATE (type)
846 && CLASSTYPE_TEMPLATE_INFO (type)
847 && context && CLASS_TYPE_P (context)
848 && CLASSTYPE_TEMPLATE_INFO (context))
850 /* This is for an explicit specialization of member class
851 template according to [temp.expl.spec/18]:
853 template <> template <class U> class C<int>::D;
855 The context `C<int>' must be an implicit instantiation.
856 Otherwise this is just a member class template declared
859 template <> class C<int> { template <class U> class D; };
860 template <> template <class U> class C<int>::D;
862 In the first case, `C<int>::D' is a specialization of `C<T>::D'
863 while in the second case, `C<int>::D' is a primary template
864 and `C<T>::D' may not exist. */
866 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
867 && !COMPLETE_TYPE_P (type))
870 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
872 if (current_namespace
873 != decl_namespace_context (tmpl))
875 permerror (input_location, "specializing %q#T in different namespace", type);
876 permerror (input_location, " from definition of %q+#D", tmpl);
879 /* Check for invalid specialization after instantiation:
881 template <> template <> class C<int>::D<int>;
882 template <> template <class U> class C<int>::D; */
884 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
885 t; t = TREE_CHAIN (t))
887 tree inst = TREE_VALUE (t);
888 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
890 /* We already have a full specialization of this partial
891 instantiation. Reassign it to the new member
892 specialization template. */
896 elt.tmpl = most_general_template (tmpl);
897 elt.args = CLASSTYPE_TI_ARGS (inst);
900 htab_remove_elt (type_specializations, &elt);
903 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
905 slot = (spec_entry **)
906 htab_find_slot (type_specializations, &elt, INSERT);
907 *slot = ggc_alloc_spec_entry ();
910 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
911 /* But if we've had an implicit instantiation, that's a
912 problem ([temp.expl.spec]/6). */
913 error ("specialization %qT after instantiation %qT",
917 /* Mark TYPE as a specialization. And as a result, we only
918 have one level of template argument for the innermost
920 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
921 CLASSTYPE_TI_ARGS (type)
922 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
925 else if (processing_specialization)
927 /* Someday C++0x may allow for enum template specialization. */
928 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
929 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
930 pedwarn (input_location, OPT_pedantic, "template specialization "
931 "of %qD not allowed by ISO C++", type);
934 error ("explicit specialization of non-template %qT", type);
935 return error_mark_node;
942 /* Returns nonzero if we can optimize the retrieval of specializations
943 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
944 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
947 optimize_specialization_lookup_p (tree tmpl)
949 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
950 && DECL_CLASS_SCOPE_P (tmpl)
951 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
953 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
954 /* The optimized lookup depends on the fact that the
955 template arguments for the member function template apply
956 purely to the containing class, which is not true if the
957 containing class is an explicit or partial
959 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
960 && !DECL_MEMBER_TEMPLATE_P (tmpl)
961 && !DECL_CONV_FN_P (tmpl)
962 /* It is possible to have a template that is not a member
963 template and is not a member of a template class:
965 template <typename T>
966 struct S { friend A::f(); };
968 Here, the friend function is a template, but the context does
969 not have template information. The optimized lookup relies
970 on having ARGS be the template arguments for both the class
971 and the function template. */
972 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
975 /* Retrieve the specialization (in the sense of [temp.spec] - a
976 specialization is either an instantiation or an explicit
977 specialization) of TMPL for the given template ARGS. If there is
978 no such specialization, return NULL_TREE. The ARGS are a vector of
979 arguments, or a vector of vectors of arguments, in the case of
980 templates with more than one level of parameters.
982 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
983 then we search for a partial specialization matching ARGS. This
984 parameter is ignored if TMPL is not a class template. */
987 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
989 if (args == error_mark_node)
992 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
994 /* There should be as many levels of arguments as there are
995 levels of parameters. */
996 gcc_assert (TMPL_ARGS_DEPTH (args)
997 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
999 if (optimize_specialization_lookup_p (tmpl))
1001 tree class_template;
1002 tree class_specialization;
1003 VEC(tree,gc) *methods;
1007 /* The template arguments actually apply to the containing
1008 class. Find the class specialization with those
1010 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1011 class_specialization
1012 = retrieve_specialization (class_template, args, 0);
1013 if (!class_specialization)
1015 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1016 for the specialization. */
1017 idx = class_method_index_for_fn (class_specialization, tmpl);
1020 /* Iterate through the methods with the indicated name, looking
1021 for the one that has an instance of TMPL. */
1022 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1023 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1025 tree fn = OVL_CURRENT (fns);
1026 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1027 /* using-declarations can add base methods to the method vec,
1028 and we don't want those here. */
1029 && DECL_CONTEXT (fn) == class_specialization)
1038 htab_t specializations;
1042 elt.spec = NULL_TREE;
1044 if (DECL_CLASS_TEMPLATE_P (tmpl))
1045 specializations = type_specializations;
1047 specializations = decl_specializations;
1050 hash = hash_specialization (&elt);
1051 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1059 /* Like retrieve_specialization, but for local declarations. */
1062 retrieve_local_specialization (tree tmpl)
1066 if (local_specializations == NULL)
1069 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1070 htab_hash_pointer (tmpl));
1071 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1074 /* Returns nonzero iff DECL is a specialization of TMPL. */
1077 is_specialization_of (tree decl, tree tmpl)
1081 if (TREE_CODE (decl) == FUNCTION_DECL)
1085 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1091 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1093 for (t = TREE_TYPE (decl);
1095 t = CLASSTYPE_USE_TEMPLATE (t)
1096 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1097 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1104 /* Returns nonzero iff DECL is a specialization of friend declaration
1105 FRIEND_DECL according to [temp.friend]. */
1108 is_specialization_of_friend (tree decl, tree friend_decl)
1110 bool need_template = true;
1113 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1114 || TREE_CODE (decl) == TYPE_DECL);
1116 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1117 of a template class, we want to check if DECL is a specialization
1119 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1120 && DECL_TEMPLATE_INFO (friend_decl)
1121 && !DECL_USE_TEMPLATE (friend_decl))
1123 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1124 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1125 need_template = false;
1127 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1128 && !PRIMARY_TEMPLATE_P (friend_decl))
1129 need_template = false;
1131 /* There is nothing to do if this is not a template friend. */
1132 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1135 if (is_specialization_of (decl, friend_decl))
1139 A member of a class template may be declared to be a friend of a
1140 non-template class. In this case, the corresponding member of
1141 every specialization of the class template is a friend of the
1142 class granting friendship.
1144 For example, given a template friend declaration
1146 template <class T> friend void A<T>::f();
1148 the member function below is considered a friend
1150 template <> struct A<int> {
1154 For this type of template friend, TEMPLATE_DEPTH below will be
1155 nonzero. To determine if DECL is a friend of FRIEND, we first
1156 check if the enclosing class is a specialization of another. */
1158 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1160 && DECL_CLASS_SCOPE_P (decl)
1161 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1162 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1164 /* Next, we check the members themselves. In order to handle
1165 a few tricky cases, such as when FRIEND_DECL's are
1167 template <class T> friend void A<T>::g(T t);
1168 template <class T> template <T t> friend void A<T>::h();
1172 void A<int>::g(int);
1173 template <int> void A<int>::h();
1175 we need to figure out ARGS, the template arguments from
1176 the context of DECL. This is required for template substitution
1177 of `T' in the function parameter of `g' and template parameter
1178 of `h' in the above examples. Here ARGS corresponds to `int'. */
1180 tree context = DECL_CONTEXT (decl);
1181 tree args = NULL_TREE;
1182 int current_depth = 0;
1184 while (current_depth < template_depth)
1186 if (CLASSTYPE_TEMPLATE_INFO (context))
1188 if (current_depth == 0)
1189 args = TYPE_TI_ARGS (context);
1191 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1194 context = TYPE_CONTEXT (context);
1197 if (TREE_CODE (decl) == FUNCTION_DECL)
1202 tree friend_args_type;
1203 tree decl_args_type;
1205 /* Make sure that both DECL and FRIEND_DECL are templates or
1207 is_template = DECL_TEMPLATE_INFO (decl)
1208 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1209 if (need_template ^ is_template)
1211 else if (is_template)
1213 /* If both are templates, check template parameter list. */
1215 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1217 if (!comp_template_parms
1218 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1222 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1225 decl_type = TREE_TYPE (decl);
1227 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1228 tf_none, NULL_TREE);
1229 if (friend_type == error_mark_node)
1232 /* Check if return types match. */
1233 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1236 /* Check if function parameter types match, ignoring the
1237 `this' parameter. */
1238 friend_args_type = TYPE_ARG_TYPES (friend_type);
1239 decl_args_type = TYPE_ARG_TYPES (decl_type);
1240 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1241 friend_args_type = TREE_CHAIN (friend_args_type);
1242 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1243 decl_args_type = TREE_CHAIN (decl_args_type);
1245 return compparms (decl_args_type, friend_args_type);
1249 /* DECL is a TYPE_DECL */
1251 tree decl_type = TREE_TYPE (decl);
1253 /* Make sure that both DECL and FRIEND_DECL are templates or
1256 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1257 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1259 if (need_template ^ is_template)
1261 else if (is_template)
1264 /* If both are templates, check the name of the two
1265 TEMPLATE_DECL's first because is_friend didn't. */
1266 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1267 != DECL_NAME (friend_decl))
1270 /* Now check template parameter list. */
1272 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1274 return comp_template_parms
1275 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1279 return (DECL_NAME (decl)
1280 == DECL_NAME (friend_decl));
1286 /* Register the specialization SPEC as a specialization of TMPL with
1287 the indicated ARGS. IS_FRIEND indicates whether the specialization
1288 is actually just a friend declaration. Returns SPEC, or an
1289 equivalent prior declaration, if available. */
1292 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1296 spec_entry **slot = NULL;
1299 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1301 if (TREE_CODE (spec) == FUNCTION_DECL
1302 && uses_template_parms (DECL_TI_ARGS (spec)))
1303 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1304 register it; we want the corresponding TEMPLATE_DECL instead.
1305 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1306 the more obvious `uses_template_parms (spec)' to avoid problems
1307 with default function arguments. In particular, given
1308 something like this:
1310 template <class T> void f(T t1, T t = T())
1312 the default argument expression is not substituted for in an
1313 instantiation unless and until it is actually needed. */
1316 if (optimize_specialization_lookup_p (tmpl))
1317 /* We don't put these specializations in the hash table, but we might
1318 want to give an error about a mismatch. */
1319 fn = retrieve_specialization (tmpl, args, 0);
1327 hash = hash_specialization (&elt);
1329 slot = (spec_entry **)
1330 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1337 /* We can sometimes try to re-register a specialization that we've
1338 already got. In particular, regenerate_decl_from_template calls
1339 duplicate_decls which will update the specialization list. But,
1340 we'll still get called again here anyhow. It's more convenient
1341 to simply allow this than to try to prevent it. */
1344 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1346 if (DECL_TEMPLATE_INSTANTIATION (fn))
1348 if (DECL_ODR_USED (fn)
1349 || DECL_EXPLICIT_INSTANTIATION (fn))
1351 error ("specialization of %qD after instantiation",
1353 return error_mark_node;
1358 /* This situation should occur only if the first
1359 specialization is an implicit instantiation, the
1360 second is an explicit specialization, and the
1361 implicit instantiation has not yet been used. That
1362 situation can occur if we have implicitly
1363 instantiated a member function and then specialized
1366 We can also wind up here if a friend declaration that
1367 looked like an instantiation turns out to be a
1370 template <class T> void foo(T);
1371 class S { friend void foo<>(int) };
1372 template <> void foo(int);
1374 We transform the existing DECL in place so that any
1375 pointers to it become pointers to the updated
1378 If there was a definition for the template, but not
1379 for the specialization, we want this to look as if
1380 there were no definition, and vice versa. */
1381 DECL_INITIAL (fn) = NULL_TREE;
1382 duplicate_decls (spec, fn, is_friend);
1383 /* The call to duplicate_decls will have applied
1386 An explicit specialization of a function template
1387 is inline only if it is explicitly declared to be,
1388 and independently of whether its function template
1391 to the primary function; now copy the inline bits to
1392 the various clones. */
1393 FOR_EACH_CLONE (clone, fn)
1395 DECL_DECLARED_INLINE_P (clone)
1396 = DECL_DECLARED_INLINE_P (fn);
1397 DECL_SOURCE_LOCATION (clone)
1398 = DECL_SOURCE_LOCATION (fn);
1400 check_specialization_namespace (fn);
1405 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1407 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1408 /* Dup decl failed, but this is a new definition. Set the
1409 line number so any errors match this new
1411 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1417 return duplicate_decls (spec, fn, is_friend);
1419 /* A specialization must be declared in the same namespace as the
1420 template it is specializing. */
1421 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1422 && !check_specialization_namespace (tmpl))
1423 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1425 if (!optimize_specialization_lookup_p (tmpl))
1427 gcc_assert (tmpl && args && spec);
1428 *slot = ggc_alloc_spec_entry ();
1430 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1431 && PRIMARY_TEMPLATE_P (tmpl)
1432 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1433 /* TMPL is a forward declaration of a template function; keep a list
1434 of all specializations in case we need to reassign them to a friend
1435 template later in tsubst_friend_function. */
1436 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1437 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1443 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1444 TMPL and ARGS members, ignores SPEC. */
1447 eq_specializations (const void *p1, const void *p2)
1449 const spec_entry *e1 = (const spec_entry *)p1;
1450 const spec_entry *e2 = (const spec_entry *)p2;
1452 return (e1->tmpl == e2->tmpl
1453 && comp_template_args (e1->args, e2->args));
1456 /* Returns a hash for a template TMPL and template arguments ARGS. */
1459 hash_tmpl_and_args (tree tmpl, tree args)
1461 hashval_t val = DECL_UID (tmpl);
1462 return iterative_hash_template_arg (args, val);
1465 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1469 hash_specialization (const void *p)
1471 const spec_entry *e = (const spec_entry *)p;
1472 return hash_tmpl_and_args (e->tmpl, e->args);
1475 /* Recursively calculate a hash value for a template argument ARG, for use
1476 in the hash tables of template specializations. */
1479 iterative_hash_template_arg (tree arg, hashval_t val)
1481 unsigned HOST_WIDE_INT i;
1482 enum tree_code code;
1485 if (arg == NULL_TREE)
1486 return iterative_hash_object (arg, val);
1491 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1492 /* We can get one of these when re-hashing a previous entry in the middle
1493 of substituting into a pack expansion. Just look through it. */
1494 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1496 code = TREE_CODE (arg);
1497 tclass = TREE_CODE_CLASS (code);
1499 val = iterative_hash_object (code, val);
1506 case IDENTIFIER_NODE:
1507 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1511 int i, len = TREE_VEC_LENGTH (arg);
1512 for (i = 0; i < len; ++i)
1513 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1517 case TYPE_PACK_EXPANSION:
1518 case EXPR_PACK_EXPANSION:
1519 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1521 case TYPE_ARGUMENT_PACK:
1522 case NONTYPE_ARGUMENT_PACK:
1523 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1526 for (; arg; arg = TREE_CHAIN (arg))
1527 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1531 for (; arg; arg = OVL_NEXT (arg))
1532 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1538 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1540 val = iterative_hash_template_arg (field, val);
1541 val = iterative_hash_template_arg (value, val);
1547 if (!DECL_ARTIFICIAL (arg))
1549 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1550 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1552 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1555 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1558 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1559 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1561 case TEMPLATE_PARM_INDEX:
1562 val = iterative_hash_template_arg
1563 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1564 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1565 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1568 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1569 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1570 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1573 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1575 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1579 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1580 code = TREE_CODE (TREE_OPERAND (arg, 1));
1581 val = iterative_hash_object (code, val);
1582 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1585 /* A lambda can't appear in a template arg, but don't crash on
1587 gcc_assert (seen_error ());
1591 case STATIC_CAST_EXPR:
1592 case REINTERPRET_CAST_EXPR:
1593 case CONST_CAST_EXPR:
1594 case DYNAMIC_CAST_EXPR:
1596 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1597 /* Now hash operands as usual. */
1607 if (TYPE_CANONICAL (arg))
1608 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1610 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1611 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1612 /* Otherwise just compare the types during lookup. */
1615 case tcc_declaration:
1617 return iterative_hash_expr (arg, val);
1620 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1622 unsigned n = cp_tree_operand_length (arg);
1623 for (i = 0; i < n; ++i)
1624 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1632 /* Unregister the specialization SPEC as a specialization of TMPL.
1633 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1634 if the SPEC was listed as a specialization of TMPL.
1636 Note that SPEC has been ggc_freed, so we can't look inside it. */
1639 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1644 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1645 elt.args = TI_ARGS (tinfo);
1646 elt.spec = NULL_TREE;
1648 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1651 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1652 gcc_assert (new_spec != NULL_TREE);
1653 (*slot)->spec = new_spec;
1660 /* Compare an entry in the local specializations hash table P1 (which
1661 is really a pointer to a TREE_LIST) with P2 (which is really a
1665 eq_local_specializations (const void *p1, const void *p2)
1667 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1670 /* Hash P1, an entry in the local specializations table. */
1673 hash_local_specialization (const void* p1)
1675 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1678 /* Like register_specialization, but for local declarations. We are
1679 registering SPEC, an instantiation of TMPL. */
1682 register_local_specialization (tree spec, tree tmpl)
1686 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1687 htab_hash_pointer (tmpl), INSERT);
1688 *slot = build_tree_list (spec, tmpl);
1691 /* TYPE is a class type. Returns true if TYPE is an explicitly
1692 specialized class. */
1695 explicit_class_specialization_p (tree type)
1697 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1699 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1702 /* Print the list of functions at FNS, going through all the overloads
1703 for each element of the list. Alternatively, FNS can not be a
1704 TREE_LIST, in which case it will be printed together with all the
1707 MORE and *STR should respectively be FALSE and NULL when the function
1708 is called from the outside. They are used internally on recursive
1709 calls. print_candidates manages the two parameters and leaves NULL
1710 in *STR when it ends. */
1713 print_candidates_1 (tree fns, bool more, const char **str)
1716 char *spaces = NULL;
1718 for (fn = fns; fn; fn = OVL_NEXT (fn))
1719 if (TREE_CODE (fn) == TREE_LIST)
1721 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1722 print_candidates_1 (TREE_VALUE (fn2),
1723 TREE_CHAIN (fn2) || more, str);
1729 /* Pick the prefix string. */
1730 if (!more && !OVL_NEXT (fns))
1732 error ("candidate is: %+#D", OVL_CURRENT (fn));
1736 *str = _("candidates are:");
1737 spaces = get_spaces (*str);
1739 error ("%s %+#D", *str, OVL_CURRENT (fn));
1740 *str = spaces ? spaces : *str;
1750 /* Print the list of candidate FNS in an error message. FNS can also
1751 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1754 print_candidates (tree fns)
1756 const char *str = NULL;
1757 print_candidates_1 (fns, false, &str);
1758 gcc_assert (str == NULL);
1761 /* Returns the template (one of the functions given by TEMPLATE_ID)
1762 which can be specialized to match the indicated DECL with the
1763 explicit template args given in TEMPLATE_ID. The DECL may be
1764 NULL_TREE if none is available. In that case, the functions in
1765 TEMPLATE_ID are non-members.
1767 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1768 specialization of a member template.
1770 The TEMPLATE_COUNT is the number of references to qualifying
1771 template classes that appeared in the name of the function. See
1772 check_explicit_specialization for a more accurate description.
1774 TSK indicates what kind of template declaration (if any) is being
1775 declared. TSK_TEMPLATE indicates that the declaration given by
1776 DECL, though a FUNCTION_DECL, has template parameters, and is
1777 therefore a template function.
1779 The template args (those explicitly specified and those deduced)
1780 are output in a newly created vector *TARGS_OUT.
1782 If it is impossible to determine the result, an error message is
1783 issued. The error_mark_node is returned to indicate failure. */
1786 determine_specialization (tree template_id,
1789 int need_member_template,
1795 tree explicit_targs;
1796 tree candidates = NULL_TREE;
1797 /* A TREE_LIST of templates of which DECL may be a specialization.
1798 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1799 corresponding TREE_PURPOSE is the set of template arguments that,
1800 when used to instantiate the template, would produce a function
1801 with the signature of DECL. */
1802 tree templates = NULL_TREE;
1804 cp_binding_level *b;
1806 *targs_out = NULL_TREE;
1808 if (template_id == error_mark_node || decl == error_mark_node)
1809 return error_mark_node;
1811 fns = TREE_OPERAND (template_id, 0);
1812 explicit_targs = TREE_OPERAND (template_id, 1);
1814 if (fns == error_mark_node)
1815 return error_mark_node;
1817 /* Check for baselinks. */
1818 if (BASELINK_P (fns))
1819 fns = BASELINK_FUNCTIONS (fns);
1821 if (!is_overloaded_fn (fns))
1823 error ("%qD is not a function template", fns);
1824 return error_mark_node;
1827 /* Count the number of template headers specified for this
1830 for (b = current_binding_level;
1831 b->kind == sk_template_parms;
1835 for (; fns; fns = OVL_NEXT (fns))
1837 tree fn = OVL_CURRENT (fns);
1839 if (TREE_CODE (fn) == TEMPLATE_DECL)
1841 tree decl_arg_types;
1844 /* In case of explicit specialization, we need to check if
1845 the number of template headers appearing in the specialization
1846 is correct. This is usually done in check_explicit_specialization,
1847 but the check done there cannot be exhaustive when specializing
1848 member functions. Consider the following code:
1850 template <> void A<int>::f(int);
1851 template <> template <> void A<int>::f(int);
1853 Assuming that A<int> is not itself an explicit specialization
1854 already, the first line specializes "f" which is a non-template
1855 member function, whilst the second line specializes "f" which
1856 is a template member function. So both lines are syntactically
1857 correct, and check_explicit_specialization does not reject
1860 Here, we can do better, as we are matching the specialization
1861 against the declarations. We count the number of template
1862 headers, and we check if they match TEMPLATE_COUNT + 1
1863 (TEMPLATE_COUNT is the number of qualifying template classes,
1864 plus there must be another header for the member template
1867 Notice that if header_count is zero, this is not a
1868 specialization but rather a template instantiation, so there
1869 is no check we can perform here. */
1870 if (header_count && header_count != template_count + 1)
1873 /* Check that the number of template arguments at the
1874 innermost level for DECL is the same as for FN. */
1875 if (current_binding_level->kind == sk_template_parms
1876 && !current_binding_level->explicit_spec_p
1877 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1878 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1879 (current_template_parms))))
1882 /* DECL might be a specialization of FN. */
1883 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1884 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1886 /* For a non-static member function, we need to make sure
1887 that the const qualification is the same. Since
1888 get_bindings does not try to merge the "this" parameter,
1889 we must do the comparison explicitly. */
1890 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1891 && !same_type_p (TREE_VALUE (fn_arg_types),
1892 TREE_VALUE (decl_arg_types)))
1895 /* Skip the "this" parameter and, for constructors of
1896 classes with virtual bases, the VTT parameter. A
1897 full specialization of a constructor will have a VTT
1898 parameter, but a template never will. */
1900 = skip_artificial_parms_for (decl, decl_arg_types);
1902 = skip_artificial_parms_for (fn, fn_arg_types);
1904 /* Check that the number of function parameters matches.
1906 template <class T> void f(int i = 0);
1907 template <> void f<int>();
1908 The specialization f<int> is invalid but is not caught
1909 by get_bindings below. */
1910 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1913 /* Function templates cannot be specializations; there are
1914 no partial specializations of functions. Therefore, if
1915 the type of DECL does not match FN, there is no
1917 if (tsk == tsk_template)
1919 if (compparms (fn_arg_types, decl_arg_types))
1920 candidates = tree_cons (NULL_TREE, fn, candidates);
1924 /* See whether this function might be a specialization of this
1926 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1929 /* We cannot deduce template arguments that when used to
1930 specialize TMPL will produce DECL. */
1933 /* Save this template, and the arguments deduced. */
1934 templates = tree_cons (targs, fn, templates);
1936 else if (need_member_template)
1937 /* FN is an ordinary member function, and we need a
1938 specialization of a member template. */
1940 else if (TREE_CODE (fn) != FUNCTION_DECL)
1941 /* We can get IDENTIFIER_NODEs here in certain erroneous
1944 else if (!DECL_FUNCTION_MEMBER_P (fn))
1945 /* This is just an ordinary non-member function. Nothing can
1946 be a specialization of that. */
1948 else if (DECL_ARTIFICIAL (fn))
1949 /* Cannot specialize functions that are created implicitly. */
1953 tree decl_arg_types;
1955 /* This is an ordinary member function. However, since
1956 we're here, we can assume it's enclosing class is a
1957 template class. For example,
1959 template <typename T> struct S { void f(); };
1960 template <> void S<int>::f() {}
1962 Here, S<int>::f is a non-template, but S<int> is a
1963 template class. If FN has the same type as DECL, we
1964 might be in business. */
1966 if (!DECL_TEMPLATE_INFO (fn))
1967 /* Its enclosing class is an explicit specialization
1968 of a template class. This is not a candidate. */
1971 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1972 TREE_TYPE (TREE_TYPE (fn))))
1973 /* The return types differ. */
1976 /* Adjust the type of DECL in case FN is a static member. */
1977 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1978 if (DECL_STATIC_FUNCTION_P (fn)
1979 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1980 decl_arg_types = TREE_CHAIN (decl_arg_types);
1982 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1985 candidates = tree_cons (NULL_TREE, fn, candidates);
1989 if (templates && TREE_CHAIN (templates))
1995 It is possible for a specialization with a given function
1996 signature to be instantiated from more than one function
1997 template. In such cases, explicit specification of the
1998 template arguments must be used to uniquely identify the
1999 function template specialization being specialized.
2001 Note that here, there's no suggestion that we're supposed to
2002 determine which of the candidate templates is most
2003 specialized. However, we, also have:
2007 Partial ordering of overloaded function template
2008 declarations is used in the following contexts to select
2009 the function template to which a function template
2010 specialization refers:
2012 -- when an explicit specialization refers to a function
2015 So, we do use the partial ordering rules, at least for now.
2016 This extension can only serve to make invalid programs valid,
2017 so it's safe. And, there is strong anecdotal evidence that
2018 the committee intended the partial ordering rules to apply;
2019 the EDG front end has that behavior, and John Spicer claims
2020 that the committee simply forgot to delete the wording in
2021 [temp.expl.spec]. */
2022 tree tmpl = most_specialized_instantiation (templates);
2023 if (tmpl != error_mark_node)
2026 TREE_CHAIN (templates) = NULL_TREE;
2030 if (templates == NULL_TREE && candidates == NULL_TREE)
2032 error ("template-id %qD for %q+D does not match any template "
2033 "declaration", template_id, decl);
2034 if (header_count && header_count != template_count + 1)
2035 inform (input_location, "saw %d %<template<>%>, need %d for "
2036 "specializing a member function template",
2037 header_count, template_count + 1);
2038 return error_mark_node;
2040 else if ((templates && TREE_CHAIN (templates))
2041 || (candidates && TREE_CHAIN (candidates))
2042 || (templates && candidates))
2044 error ("ambiguous template specialization %qD for %q+D",
2046 candidates = chainon (candidates, templates);
2047 print_candidates (candidates);
2048 return error_mark_node;
2051 /* We have one, and exactly one, match. */
2054 tree fn = TREE_VALUE (candidates);
2055 *targs_out = copy_node (DECL_TI_ARGS (fn));
2056 /* DECL is a re-declaration or partial instantiation of a template
2058 if (TREE_CODE (fn) == TEMPLATE_DECL)
2060 /* It was a specialization of an ordinary member function in a
2062 return DECL_TI_TEMPLATE (fn);
2065 /* It was a specialization of a template. */
2066 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2067 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2069 *targs_out = copy_node (targs);
2070 SET_TMPL_ARGS_LEVEL (*targs_out,
2071 TMPL_ARGS_DEPTH (*targs_out),
2072 TREE_PURPOSE (templates));
2075 *targs_out = TREE_PURPOSE (templates);
2076 return TREE_VALUE (templates);
2079 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2080 but with the default argument values filled in from those in the
2084 copy_default_args_to_explicit_spec_1 (tree spec_types,
2087 tree new_spec_types;
2092 if (spec_types == void_list_node)
2093 return void_list_node;
2095 /* Substitute into the rest of the list. */
2097 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2098 TREE_CHAIN (tmpl_types));
2100 /* Add the default argument for this parameter. */
2101 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2102 TREE_VALUE (spec_types),
2106 /* DECL is an explicit specialization. Replicate default arguments
2107 from the template it specializes. (That way, code like:
2109 template <class T> void f(T = 3);
2110 template <> void f(double);
2113 works, as required.) An alternative approach would be to look up
2114 the correct default arguments at the call-site, but this approach
2115 is consistent with how implicit instantiations are handled. */
2118 copy_default_args_to_explicit_spec (tree decl)
2123 tree new_spec_types;
2127 tree object_type = NULL_TREE;
2128 tree in_charge = NULL_TREE;
2129 tree vtt = NULL_TREE;
2131 /* See if there's anything we need to do. */
2132 tmpl = DECL_TI_TEMPLATE (decl);
2133 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2134 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2135 if (TREE_PURPOSE (t))
2140 old_type = TREE_TYPE (decl);
2141 spec_types = TYPE_ARG_TYPES (old_type);
2143 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2145 /* Remove the this pointer, but remember the object's type for
2147 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2148 spec_types = TREE_CHAIN (spec_types);
2149 tmpl_types = TREE_CHAIN (tmpl_types);
2151 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2153 /* DECL may contain more parameters than TMPL due to the extra
2154 in-charge parameter in constructors and destructors. */
2155 in_charge = spec_types;
2156 spec_types = TREE_CHAIN (spec_types);
2158 if (DECL_HAS_VTT_PARM_P (decl))
2161 spec_types = TREE_CHAIN (spec_types);
2165 /* Compute the merged default arguments. */
2167 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2169 /* Compute the new FUNCTION_TYPE. */
2173 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2178 /* Put the in-charge parameter back. */
2179 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2180 TREE_VALUE (in_charge),
2183 new_type = build_method_type_directly (object_type,
2184 TREE_TYPE (old_type),
2188 new_type = build_function_type (TREE_TYPE (old_type),
2190 new_type = cp_build_type_attribute_variant (new_type,
2191 TYPE_ATTRIBUTES (old_type));
2192 new_type = build_exception_variant (new_type,
2193 TYPE_RAISES_EXCEPTIONS (old_type));
2194 TREE_TYPE (decl) = new_type;
2197 /* Check to see if the function just declared, as indicated in
2198 DECLARATOR, and in DECL, is a specialization of a function
2199 template. We may also discover that the declaration is an explicit
2200 instantiation at this point.
2202 Returns DECL, or an equivalent declaration that should be used
2203 instead if all goes well. Issues an error message if something is
2204 amiss. Returns error_mark_node if the error is not easily
2207 FLAGS is a bitmask consisting of the following flags:
2209 2: The function has a definition.
2210 4: The function is a friend.
2212 The TEMPLATE_COUNT is the number of references to qualifying
2213 template classes that appeared in the name of the function. For
2216 template <class T> struct S { void f(); };
2219 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2220 classes are not counted in the TEMPLATE_COUNT, so that in
2222 template <class T> struct S {};
2223 template <> struct S<int> { void f(); }
2224 template <> void S<int>::f();
2226 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2227 invalid; there should be no template <>.)
2229 If the function is a specialization, it is marked as such via
2230 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2231 is set up correctly, and it is added to the list of specializations
2232 for that template. */
2235 check_explicit_specialization (tree declarator,
2240 int have_def = flags & 2;
2241 int is_friend = flags & 4;
2242 int specialization = 0;
2243 int explicit_instantiation = 0;
2244 int member_specialization = 0;
2245 tree ctype = DECL_CLASS_CONTEXT (decl);
2246 tree dname = DECL_NAME (decl);
2251 if (!processing_specialization)
2254 tsk = tsk_excessive_parms;
2257 tsk = current_tmpl_spec_kind (template_count);
2262 if (processing_specialization)
2265 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2267 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2270 /* This could be something like:
2272 template <class T> void f(T);
2273 class S { friend void f<>(int); } */
2277 /* This case handles bogus declarations like template <>
2278 template <class T> void f<int>(); */
2280 error ("template-id %qD in declaration of primary template",
2287 case tsk_invalid_member_spec:
2288 /* The error has already been reported in
2289 check_specialization_scope. */
2290 return error_mark_node;
2292 case tsk_invalid_expl_inst:
2293 error ("template parameter list used in explicit instantiation");
2299 error ("definition provided for explicit instantiation");
2301 explicit_instantiation = 1;
2304 case tsk_excessive_parms:
2305 case tsk_insufficient_parms:
2306 if (tsk == tsk_excessive_parms)
2307 error ("too many template parameter lists in declaration of %qD",
2309 else if (template_header_count)
2310 error("too few template parameter lists in declaration of %qD", decl);
2312 error("explicit specialization of %qD must be introduced by "
2313 "%<template <>%>", decl);
2317 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2319 member_specialization = 1;
2325 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2327 /* This case handles bogus declarations like template <>
2328 template <class T> void f<int>(); */
2330 if (uses_template_parms (declarator))
2331 error ("function template partial specialization %qD "
2332 "is not allowed", declarator);
2334 error ("template-id %qD in declaration of primary template",
2339 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2340 /* This is a specialization of a member template, without
2341 specialization the containing class. Something like:
2343 template <class T> struct S {
2344 template <class U> void f (U);
2346 template <> template <class U> void S<int>::f(U) {}
2348 That's a specialization -- but of the entire template. */
2356 if (specialization || member_specialization)
2358 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2359 for (; t; t = TREE_CHAIN (t))
2360 if (TREE_PURPOSE (t))
2362 permerror (input_location,
2363 "default argument specified in explicit specialization");
2368 if (specialization || member_specialization || explicit_instantiation)
2370 tree tmpl = NULL_TREE;
2371 tree targs = NULL_TREE;
2373 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2374 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2378 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2383 /* If there is no class context, the explicit instantiation
2384 must be at namespace scope. */
2385 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2387 /* Find the namespace binding, using the declaration
2389 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2391 if (fns == error_mark_node || !is_overloaded_fn (fns))
2393 error ("%qD is not a template function", dname);
2394 fns = error_mark_node;
2398 tree fn = OVL_CURRENT (fns);
2399 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2400 CP_DECL_CONTEXT (fn)))
2401 error ("%qD is not declared in %qD",
2402 decl, current_namespace);
2406 declarator = lookup_template_function (fns, NULL_TREE);
2409 if (declarator == error_mark_node)
2410 return error_mark_node;
2412 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2414 if (!explicit_instantiation)
2415 /* A specialization in class scope. This is invalid,
2416 but the error will already have been flagged by
2417 check_specialization_scope. */
2418 return error_mark_node;
2421 /* It's not valid to write an explicit instantiation in
2424 class C { template void f(); }
2426 This case is caught by the parser. However, on
2429 template class C { void f(); };
2431 (which is invalid) we can get here. The error will be
2438 else if (ctype != NULL_TREE
2439 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2442 /* Find the list of functions in ctype that have the same
2443 name as the declared function. */
2444 tree name = TREE_OPERAND (declarator, 0);
2445 tree fns = NULL_TREE;
2448 if (constructor_name_p (name, ctype))
2450 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2452 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2453 : !CLASSTYPE_DESTRUCTORS (ctype))
2455 /* From [temp.expl.spec]:
2457 If such an explicit specialization for the member
2458 of a class template names an implicitly-declared
2459 special member function (clause _special_), the
2460 program is ill-formed.
2462 Similar language is found in [temp.explicit]. */
2463 error ("specialization of implicitly-declared special member function");
2464 return error_mark_node;
2467 name = is_constructor ? ctor_identifier : dtor_identifier;
2470 if (!DECL_CONV_FN_P (decl))
2472 idx = lookup_fnfields_1 (ctype, name);
2474 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2478 VEC(tree,gc) *methods;
2481 /* For a type-conversion operator, we cannot do a
2482 name-based lookup. We might be looking for `operator
2483 int' which will be a specialization of `operator T'.
2484 So, we find *all* the conversion operators, and then
2485 select from them. */
2488 methods = CLASSTYPE_METHOD_VEC (ctype);
2490 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2491 VEC_iterate (tree, methods, idx, ovl);
2494 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2495 /* There are no more conversion functions. */
2498 /* Glue all these conversion functions together
2499 with those we already have. */
2500 for (; ovl; ovl = OVL_NEXT (ovl))
2501 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2505 if (fns == NULL_TREE)
2507 error ("no member function %qD declared in %qT", name, ctype);
2508 return error_mark_node;
2511 TREE_OPERAND (declarator, 0) = fns;
2514 /* Figure out what exactly is being specialized at this point.
2515 Note that for an explicit instantiation, even one for a
2516 member function, we cannot tell apriori whether the
2517 instantiation is for a member template, or just a member
2518 function of a template class. Even if a member template is
2519 being instantiated, the member template arguments may be
2520 elided if they can be deduced from the rest of the
2522 tmpl = determine_specialization (declarator, decl,
2524 member_specialization,
2528 if (!tmpl || tmpl == error_mark_node)
2529 /* We couldn't figure out what this declaration was
2531 return error_mark_node;
2534 tree gen_tmpl = most_general_template (tmpl);
2536 if (explicit_instantiation)
2538 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2539 is done by do_decl_instantiation later. */
2541 int arg_depth = TMPL_ARGS_DEPTH (targs);
2542 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2544 if (arg_depth > parm_depth)
2546 /* If TMPL is not the most general template (for
2547 example, if TMPL is a friend template that is
2548 injected into namespace scope), then there will
2549 be too many levels of TARGS. Remove some of them
2554 new_targs = make_tree_vec (parm_depth);
2555 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2556 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2557 = TREE_VEC_ELT (targs, i);
2561 return instantiate_template (tmpl, targs, tf_error);
2564 /* If we thought that the DECL was a member function, but it
2565 turns out to be specializing a static member function,
2566 make DECL a static member function as well. */
2567 if (DECL_STATIC_FUNCTION_P (tmpl)
2568 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2569 revert_static_member_fn (decl);
2571 /* If this is a specialization of a member template of a
2572 template class, we want to return the TEMPLATE_DECL, not
2573 the specialization of it. */
2574 if (tsk == tsk_template)
2576 tree result = DECL_TEMPLATE_RESULT (tmpl);
2577 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2578 DECL_INITIAL (result) = NULL_TREE;
2582 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2583 DECL_SOURCE_LOCATION (result)
2584 = DECL_SOURCE_LOCATION (decl);
2585 /* We want to use the argument list specified in the
2586 definition, not in the original declaration. */
2587 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2588 for (parm = DECL_ARGUMENTS (result); parm;
2589 parm = DECL_CHAIN (parm))
2590 DECL_CONTEXT (parm) = result;
2592 return register_specialization (tmpl, gen_tmpl, targs,
2596 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2597 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2599 /* Inherit default function arguments from the template
2600 DECL is specializing. */
2601 copy_default_args_to_explicit_spec (decl);
2603 /* This specialization has the same protection as the
2604 template it specializes. */
2605 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2606 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2608 /* 7.1.1-1 [dcl.stc]
2610 A storage-class-specifier shall not be specified in an
2611 explicit specialization...
2613 The parser rejects these, so unless action is taken here,
2614 explicit function specializations will always appear with
2617 The action recommended by the C++ CWG in response to C++
2618 defect report 605 is to make the storage class and linkage
2619 of the explicit specialization match the templated function:
2621 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2623 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2625 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2626 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2628 /* This specialization has the same linkage and visibility as
2629 the function template it specializes. */
2630 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2631 if (! TREE_PUBLIC (decl))
2633 DECL_INTERFACE_KNOWN (decl) = 1;
2634 DECL_NOT_REALLY_EXTERN (decl) = 1;
2636 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2637 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2639 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2640 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2644 /* If DECL is a friend declaration, declared using an
2645 unqualified name, the namespace associated with DECL may
2646 have been set incorrectly. For example, in:
2648 template <typename T> void f(T);
2650 struct S { friend void f<int>(int); }
2653 we will have set the DECL_CONTEXT for the friend
2654 declaration to N, rather than to the global namespace. */
2655 if (DECL_NAMESPACE_SCOPE_P (decl))
2656 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2658 if (is_friend && !have_def)
2659 /* This is not really a declaration of a specialization.
2660 It's just the name of an instantiation. But, it's not
2661 a request for an instantiation, either. */
2662 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2663 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2664 /* This is indeed a specialization. In case of constructors
2665 and destructors, we need in-charge and not-in-charge
2666 versions in V3 ABI. */
2667 clone_function_decl (decl, /*update_method_vec_p=*/0);
2669 /* Register this specialization so that we can find it
2671 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2678 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2679 parameters. These are represented in the same format used for
2680 DECL_TEMPLATE_PARMS. */
2683 comp_template_parms (const_tree parms1, const_tree parms2)
2688 if (parms1 == parms2)
2691 for (p1 = parms1, p2 = parms2;
2692 p1 != NULL_TREE && p2 != NULL_TREE;
2693 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2695 tree t1 = TREE_VALUE (p1);
2696 tree t2 = TREE_VALUE (p2);
2699 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2700 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2702 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2705 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2707 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2708 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2710 /* If either of the template parameters are invalid, assume
2711 they match for the sake of error recovery. */
2712 if (parm1 == error_mark_node || parm2 == error_mark_node)
2715 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2718 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2719 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2720 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2722 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2727 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2728 /* One set of parameters has more parameters lists than the
2735 /* Determine whether PARM is a parameter pack. */
2738 template_parameter_pack_p (const_tree parm)
2740 /* Determine if we have a non-type template parameter pack. */
2741 if (TREE_CODE (parm) == PARM_DECL)
2742 return (DECL_TEMPLATE_PARM_P (parm)
2743 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2745 /* If this is a list of template parameters, we could get a
2746 TYPE_DECL or a TEMPLATE_DECL. */
2747 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2748 parm = TREE_TYPE (parm);
2750 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2751 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2752 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2755 /* Determine if T is a function parameter pack. */
2758 function_parameter_pack_p (const_tree t)
2760 if (t && TREE_CODE (t) == PARM_DECL)
2761 return FUNCTION_PARAMETER_PACK_P (t);
2765 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2766 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2769 get_function_template_decl (const_tree primary_func_tmpl_inst)
2771 if (! primary_func_tmpl_inst
2772 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2773 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2776 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2779 /* Return true iff the function parameter PARAM_DECL was expanded
2780 from the function parameter pack PACK. */
2783 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2785 if (DECL_ARTIFICIAL (param_decl)
2786 || !function_parameter_pack_p (pack))
2789 /* The parameter pack and its pack arguments have the same
2791 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2794 /* Determine whether ARGS describes a variadic template args list,
2795 i.e., one that is terminated by a template argument pack. */
2798 template_args_variadic_p (tree args)
2803 if (args == NULL_TREE)
2806 args = INNERMOST_TEMPLATE_ARGS (args);
2807 nargs = TREE_VEC_LENGTH (args);
2812 last_parm = TREE_VEC_ELT (args, nargs - 1);
2814 return ARGUMENT_PACK_P (last_parm);
2817 /* Generate a new name for the parameter pack name NAME (an
2818 IDENTIFIER_NODE) that incorporates its */
2821 make_ith_pack_parameter_name (tree name, int i)
2823 /* Munge the name to include the parameter index. */
2824 #define NUMBUF_LEN 128
2825 char numbuf[NUMBUF_LEN];
2829 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2830 newname_len = IDENTIFIER_LENGTH (name)
2831 + strlen (numbuf) + 2;
2832 newname = (char*)alloca (newname_len);
2833 snprintf (newname, newname_len,
2834 "%s#%i", IDENTIFIER_POINTER (name), i);
2835 return get_identifier (newname);
2838 /* Return true if T is a primary function
2839 or class template instantiation. */
2842 primary_template_instantiation_p (const_tree t)
2847 if (TREE_CODE (t) == FUNCTION_DECL)
2848 return DECL_LANG_SPECIFIC (t)
2849 && DECL_TEMPLATE_INSTANTIATION (t)
2850 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2851 else if (CLASS_TYPE_P (t))
2852 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2853 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2857 /* Return true if PARM is a template template parameter. */
2860 template_template_parameter_p (const_tree parm)
2862 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2865 /* Return the template parameters of T if T is a
2866 primary template instantiation, NULL otherwise. */
2869 get_primary_template_innermost_parameters (const_tree t)
2871 tree parms = NULL, template_info = NULL;
2873 if ((template_info = get_template_info (t))
2874 && primary_template_instantiation_p (t))
2875 parms = INNERMOST_TEMPLATE_PARMS
2876 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2881 /* Return the template parameters of the LEVELth level from the full list
2882 of template parameters PARMS. */
2885 get_template_parms_at_level (tree parms, int level)
2889 || TREE_CODE (parms) != TREE_LIST
2890 || level > TMPL_PARMS_DEPTH (parms))
2893 for (p = parms; p; p = TREE_CHAIN (p))
2894 if (TMPL_PARMS_DEPTH (p) == level)
2900 /* Returns the template arguments of T if T is a template instantiation,
2904 get_template_innermost_arguments (const_tree t)
2906 tree args = NULL, template_info = NULL;
2908 if ((template_info = get_template_info (t))
2909 && TI_ARGS (template_info))
2910 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2915 /* Return the argument pack elements of T if T is a template argument pack,
2919 get_template_argument_pack_elems (const_tree t)
2921 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2922 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2925 return ARGUMENT_PACK_ARGS (t);
2928 /* Structure used to track the progress of find_parameter_packs_r. */
2929 struct find_parameter_pack_data
2931 /* TREE_LIST that will contain all of the parameter packs found by
2933 tree* parameter_packs;
2935 /* Set of AST nodes that have been visited by the traversal. */
2936 struct pointer_set_t *visited;
2939 /* Identifies all of the argument packs that occur in a template
2940 argument and appends them to the TREE_LIST inside DATA, which is a
2941 find_parameter_pack_data structure. This is a subroutine of
2942 make_pack_expansion and uses_parameter_packs. */
2944 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2947 struct find_parameter_pack_data* ppd =
2948 (struct find_parameter_pack_data*)data;
2949 bool parameter_pack_p = false;
2951 /* Identify whether this is a parameter pack or not. */
2952 switch (TREE_CODE (t))
2954 case TEMPLATE_PARM_INDEX:
2955 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2956 parameter_pack_p = true;
2959 case TEMPLATE_TYPE_PARM:
2960 case TEMPLATE_TEMPLATE_PARM:
2961 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2962 parameter_pack_p = true;
2966 if (FUNCTION_PARAMETER_PACK_P (t))
2968 /* We don't want to walk into the type of a PARM_DECL,
2969 because we don't want to see the type parameter pack. */
2971 parameter_pack_p = true;
2976 /* Not a parameter pack. */
2980 if (parameter_pack_p)
2982 /* Add this parameter pack to the list. */
2983 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2987 cp_walk_tree (&TYPE_CONTEXT (t),
2988 &find_parameter_packs_r, ppd, ppd->visited);
2990 /* This switch statement will return immediately if we don't find a
2992 switch (TREE_CODE (t))
2994 case TEMPLATE_PARM_INDEX:
2997 case BOUND_TEMPLATE_TEMPLATE_PARM:
2998 /* Check the template itself. */
2999 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3000 &find_parameter_packs_r, ppd, ppd->visited);
3001 /* Check the template arguments. */
3002 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3007 case TEMPLATE_TYPE_PARM:
3008 case TEMPLATE_TEMPLATE_PARM:
3015 if (TYPE_PTRMEMFUNC_P (t))
3021 if (TYPE_TEMPLATE_INFO (t))
3022 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3023 &find_parameter_packs_r, ppd, ppd->visited);
3030 cp_walk_tree (&TREE_TYPE (t),
3031 &find_parameter_packs_r, ppd, ppd->visited);
3035 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3040 case TYPE_PACK_EXPANSION:
3041 case EXPR_PACK_EXPANSION:
3046 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3051 case IDENTIFIER_NODE:
3052 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3064 /* Determines if the expression or type T uses any parameter packs. */
3066 uses_parameter_packs (tree t)
3068 tree parameter_packs = NULL_TREE;
3069 struct find_parameter_pack_data ppd;
3070 ppd.parameter_packs = ¶meter_packs;
3071 ppd.visited = pointer_set_create ();
3072 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3073 pointer_set_destroy (ppd.visited);
3074 return parameter_packs != NULL_TREE;
3077 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3078 representation a base-class initializer into a parameter pack
3079 expansion. If all goes well, the resulting node will be an
3080 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3083 make_pack_expansion (tree arg)
3086 tree parameter_packs = NULL_TREE;
3087 bool for_types = false;
3088 struct find_parameter_pack_data ppd;
3090 if (!arg || arg == error_mark_node)
3093 if (TREE_CODE (arg) == TREE_LIST)
3095 /* The only time we will see a TREE_LIST here is for a base
3096 class initializer. In this case, the TREE_PURPOSE will be a
3097 _TYPE node (representing the base class expansion we're
3098 initializing) and the TREE_VALUE will be a TREE_LIST
3099 containing the initialization arguments.
3101 The resulting expansion looks somewhat different from most
3102 expansions. Rather than returning just one _EXPANSION, we
3103 return a TREE_LIST whose TREE_PURPOSE is a
3104 TYPE_PACK_EXPANSION containing the bases that will be
3105 initialized. The TREE_VALUE will be identical to the
3106 original TREE_VALUE, which is a list of arguments that will
3107 be passed to each base. We do not introduce any new pack
3108 expansion nodes into the TREE_VALUE (although it is possible
3109 that some already exist), because the TREE_PURPOSE and
3110 TREE_VALUE all need to be expanded together with the same
3111 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3112 resulting TREE_PURPOSE will mention the parameter packs in
3113 both the bases and the arguments to the bases. */
3116 tree parameter_packs = NULL_TREE;
3118 /* Determine which parameter packs will be used by the base
3120 ppd.visited = pointer_set_create ();
3121 ppd.parameter_packs = ¶meter_packs;
3122 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3125 if (parameter_packs == NULL_TREE)
3127 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3128 pointer_set_destroy (ppd.visited);
3129 return error_mark_node;
3132 if (TREE_VALUE (arg) != void_type_node)
3134 /* Collect the sets of parameter packs used in each of the
3135 initialization arguments. */
3136 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3138 /* Determine which parameter packs will be expanded in this
3140 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3145 pointer_set_destroy (ppd.visited);
3147 /* Create the pack expansion type for the base type. */
3148 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3149 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3150 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3152 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3153 they will rarely be compared to anything. */
3154 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3156 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3159 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3162 /* Build the PACK_EXPANSION_* node. */
3164 ? cxx_make_type (TYPE_PACK_EXPANSION)
3165 : make_node (EXPR_PACK_EXPANSION);
3166 SET_PACK_EXPANSION_PATTERN (result, arg);
3167 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3169 /* Propagate type and const-expression information. */
3170 TREE_TYPE (result) = TREE_TYPE (arg);
3171 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3174 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3175 they will rarely be compared to anything. */
3176 SET_TYPE_STRUCTURAL_EQUALITY (result);
3178 /* Determine which parameter packs will be expanded. */
3179 ppd.parameter_packs = ¶meter_packs;
3180 ppd.visited = pointer_set_create ();
3181 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3182 pointer_set_destroy (ppd.visited);
3184 /* Make sure we found some parameter packs. */
3185 if (parameter_packs == NULL_TREE)
3188 error ("expansion pattern %<%T%> contains no argument packs", arg);
3190 error ("expansion pattern %<%E%> contains no argument packs", arg);
3191 return error_mark_node;
3193 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3198 /* Checks T for any "bare" parameter packs, which have not yet been
3199 expanded, and issues an error if any are found. This operation can
3200 only be done on full expressions or types (e.g., an expression
3201 statement, "if" condition, etc.), because we could have expressions like:
3203 foo(f(g(h(args)))...)
3205 where "args" is a parameter pack. check_for_bare_parameter_packs
3206 should not be called for the subexpressions args, h(args),
3207 g(h(args)), or f(g(h(args))), because we would produce erroneous
3210 Returns TRUE and emits an error if there were bare parameter packs,
3211 returns FALSE otherwise. */
3213 check_for_bare_parameter_packs (tree t)
3215 tree parameter_packs = NULL_TREE;
3216 struct find_parameter_pack_data ppd;
3218 if (!processing_template_decl || !t || t == error_mark_node)
3221 if (TREE_CODE (t) == TYPE_DECL)
3224 ppd.parameter_packs = ¶meter_packs;
3225 ppd.visited = pointer_set_create ();
3226 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3227 pointer_set_destroy (ppd.visited);
3229 if (parameter_packs)
3231 error ("parameter packs not expanded with %<...%>:");
3232 while (parameter_packs)
3234 tree pack = TREE_VALUE (parameter_packs);
3235 tree name = NULL_TREE;
3237 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3238 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3239 name = TYPE_NAME (pack);
3240 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3241 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3243 name = DECL_NAME (pack);
3246 inform (input_location, " %qD", name);
3248 inform (input_location, " <anonymous>");
3250 parameter_packs = TREE_CHAIN (parameter_packs);
3259 /* Expand any parameter packs that occur in the template arguments in
3262 expand_template_argument_pack (tree args)
3264 tree result_args = NULL_TREE;
3265 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3266 int num_result_args = -1;
3267 int non_default_args_count = -1;
3269 /* First, determine if we need to expand anything, and the number of
3270 slots we'll need. */
3271 for (in_arg = 0; in_arg < nargs; ++in_arg)
3273 tree arg = TREE_VEC_ELT (args, in_arg);
3274 if (arg == NULL_TREE)
3276 if (ARGUMENT_PACK_P (arg))
3278 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3279 if (num_result_args < 0)
3280 num_result_args = in_arg + num_packed;
3282 num_result_args += num_packed;
3286 if (num_result_args >= 0)
3291 /* If no expansion is necessary, we're done. */
3292 if (num_result_args < 0)
3295 /* Expand arguments. */
3296 result_args = make_tree_vec (num_result_args);
3297 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3298 non_default_args_count =
3299 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3300 for (in_arg = 0; in_arg < nargs; ++in_arg)
3302 tree arg = TREE_VEC_ELT (args, in_arg);
3303 if (ARGUMENT_PACK_P (arg))
3305 tree packed = ARGUMENT_PACK_ARGS (arg);
3306 int i, num_packed = TREE_VEC_LENGTH (packed);
3307 for (i = 0; i < num_packed; ++i, ++out_arg)
3308 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3309 if (non_default_args_count > 0)
3310 non_default_args_count += num_packed;
3314 TREE_VEC_ELT (result_args, out_arg) = arg;
3318 if (non_default_args_count >= 0)
3319 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3323 /* Checks if DECL shadows a template parameter.
3325 [temp.local]: A template-parameter shall not be redeclared within its
3326 scope (including nested scopes).
3328 Emits an error and returns TRUE if the DECL shadows a parameter,
3329 returns FALSE otherwise. */
3332 check_template_shadow (tree decl)
3336 /* If we're not in a template, we can't possibly shadow a template
3338 if (!current_template_parms)
3341 /* Figure out what we're shadowing. */
3342 if (TREE_CODE (decl) == OVERLOAD)
3343 decl = OVL_CURRENT (decl);
3344 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3346 /* If there's no previous binding for this name, we're not shadowing
3347 anything, let alone a template parameter. */
3351 /* If we're not shadowing a template parameter, we're done. Note
3352 that OLDDECL might be an OVERLOAD (or perhaps even an
3353 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3355 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3358 /* We check for decl != olddecl to avoid bogus errors for using a
3359 name inside a class. We check TPFI to avoid duplicate errors for
3360 inline member templates. */
3362 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3365 error ("declaration of %q+#D", decl);
3366 error (" shadows template parm %q+#D", olddecl);
3370 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3371 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3372 template parameters. */
3375 build_template_parm_index (int index,
3382 tree t = make_node (TEMPLATE_PARM_INDEX);
3383 TEMPLATE_PARM_IDX (t) = index;
3384 TEMPLATE_PARM_LEVEL (t) = level;
3385 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3386 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3387 TEMPLATE_PARM_DECL (t) = decl;
3388 TREE_TYPE (t) = type;
3389 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3390 TREE_READONLY (t) = TREE_READONLY (decl);
3395 /* Find the canonical type parameter for the given template type
3396 parameter. Returns the canonical type parameter, which may be TYPE
3397 if no such parameter existed. */
3400 canonical_type_parameter (tree type)
3403 int idx = TEMPLATE_TYPE_IDX (type);
3404 if (!canonical_template_parms)
3405 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3407 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3408 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3410 list = VEC_index (tree, canonical_template_parms, idx);
3411 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3412 list = TREE_CHAIN (list);
3415 return TREE_VALUE (list);
3418 VEC_replace(tree, canonical_template_parms, idx,
3419 tree_cons (NULL_TREE, type,
3420 VEC_index (tree, canonical_template_parms, idx)));
3425 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3426 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3427 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3428 new one is created. */
3431 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3432 tsubst_flags_t complain)
3434 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3435 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3436 != TEMPLATE_PARM_LEVEL (index) - levels)
3437 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3439 tree orig_decl = TEMPLATE_PARM_DECL (index);
3442 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3443 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3444 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3445 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3446 DECL_ARTIFICIAL (decl) = 1;
3447 SET_DECL_TEMPLATE_PARM_P (decl);
3449 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3450 TEMPLATE_PARM_LEVEL (index) - levels,
3451 TEMPLATE_PARM_ORIG_LEVEL (index),
3452 TEMPLATE_PARM_NUM_SIBLINGS (index),
3454 TEMPLATE_PARM_DESCENDANTS (index) = t;
3455 TEMPLATE_PARM_PARAMETER_PACK (t)
3456 = TEMPLATE_PARM_PARAMETER_PACK (index);
3458 /* Template template parameters need this. */
3459 if (TREE_CODE (decl) == TEMPLATE_DECL)
3460 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3461 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3465 return TEMPLATE_PARM_DESCENDANTS (index);
3468 /* Process information from new template parameter PARM and append it
3469 to the LIST being built. This new parameter is a non-type
3470 parameter iff IS_NON_TYPE is true. This new parameter is a
3471 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3472 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3473 parameter list PARM belongs to. This is used used to create a
3474 proper canonical type for the type of PARM that is to be created,
3475 iff PARM is a type. If the size is not known, this parameter shall
3479 process_template_parm (tree list, location_t parm_loc, tree parm,
3480 bool is_non_type, bool is_parameter_pack,
3481 unsigned num_template_parms)
3488 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3489 defval = TREE_PURPOSE (parm);
3493 tree p = tree_last (list);
3495 if (p && TREE_VALUE (p) != error_mark_node)
3498 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3499 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3501 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3511 parm = TREE_VALUE (parm);
3513 SET_DECL_TEMPLATE_PARM_P (parm);
3515 if (TREE_TYPE (parm) == error_mark_node)
3517 err_parm_list = build_tree_list (defval, parm);
3518 TREE_VALUE (err_parm_list) = error_mark_node;
3519 return chainon (list, err_parm_list);
3525 The top-level cv-qualifiers on the template-parameter are
3526 ignored when determining its type. */
3527 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3528 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3530 err_parm_list = build_tree_list (defval, parm);
3531 TREE_VALUE (err_parm_list) = error_mark_node;
3532 return chainon (list, err_parm_list);
3535 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3537 /* This template parameter is not a parameter pack, but it
3538 should be. Complain about "bare" parameter packs. */
3539 check_for_bare_parameter_packs (TREE_TYPE (parm));
3541 /* Recover by calling this a parameter pack. */
3542 is_parameter_pack = true;
3546 /* A template parameter is not modifiable. */
3547 TREE_CONSTANT (parm) = 1;
3548 TREE_READONLY (parm) = 1;
3549 decl = build_decl (parm_loc,
3550 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3551 TREE_CONSTANT (decl) = 1;
3552 TREE_READONLY (decl) = 1;
3553 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3554 = build_template_parm_index (idx, processing_template_decl,
3555 processing_template_decl,
3557 decl, TREE_TYPE (parm));
3559 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3560 = is_parameter_pack;
3565 parm = TREE_VALUE (TREE_VALUE (parm));
3567 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3569 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3570 /* This is for distinguishing between real templates and template
3571 template parameters */
3572 TREE_TYPE (parm) = t;
3573 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3578 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3579 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3580 decl = build_decl (parm_loc,
3581 TYPE_DECL, parm, t);
3584 TYPE_NAME (t) = decl;
3585 TYPE_STUB_DECL (t) = decl;
3587 TEMPLATE_TYPE_PARM_INDEX (t)
3588 = build_template_parm_index (idx, processing_template_decl,
3589 processing_template_decl,
3591 decl, TREE_TYPE (parm));
3592 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3593 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3595 DECL_ARTIFICIAL (decl) = 1;
3596 SET_DECL_TEMPLATE_PARM_P (decl);
3598 parm = build_tree_list (defval, parm);
3599 return chainon (list, parm);
3602 /* The end of a template parameter list has been reached. Process the
3603 tree list into a parameter vector, converting each parameter into a more
3604 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3608 end_template_parm_list (tree parms)
3612 tree saved_parmlist = make_tree_vec (list_length (parms));
3614 current_template_parms
3615 = tree_cons (size_int (processing_template_decl),
3616 saved_parmlist, current_template_parms);
3618 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3620 next = TREE_CHAIN (parm);
3621 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3622 TREE_CHAIN (parm) = NULL_TREE;
3625 --processing_template_parmlist;
3627 return saved_parmlist;
3630 /* Create a new type almost identical to TYPE but which has the
3631 following differences:
3633 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3634 template sibling parameters of T.
3636 2/ T has a new canonical type that matches the new number
3639 3/ From now on, T is going to be what lookups referring to the
3640 name of TYPE will return. No lookup should return TYPE anymore.
3642 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3644 This is a subroutine of fixup_template_parms. */
3647 fixup_template_type_parm_type (tree type, int num_parms)
3649 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3651 /* This is the decl which name is inserted into the symbol table for
3652 the template parm type. So whenever we lookup the type name, this
3653 is the DECL we get. */
3656 /* Do not fix up the type twice. */
3657 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3660 t = copy_type (type);
3661 decl = TYPE_NAME (t);
3663 TYPE_MAIN_VARIANT (t) = t;
3664 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3665 TYPE_POINTER_TO (t) = 0;
3666 TYPE_REFERENCE_TO (t) = 0;
3668 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3669 TEMPLATE_PARM_LEVEL (orig_idx),
3670 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3673 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3674 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3675 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3677 TYPE_STUB_DECL (t) = decl;
3678 TEMPLATE_TYPE_DECL (t) = decl;
3679 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3680 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3682 /* Update the type associated to the type name stored in the symbol
3683 table. Now, whenever the type name is looked up, the resulting
3684 type is properly fixed up. */
3685 TREE_TYPE (decl) = t;
3687 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3692 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3693 identical to I, but that is fixed up as to:
3695 1/ carry the number of sibling parms (NUM_PARMS) of the template
3696 parm represented by I.
3698 2/ replace all references to template parm types declared before I
3699 (in the same template parm list as I) by references to template
3700 parm types contained in ARGS. ARGS should contain the list of
3701 template parms that have been fixed up so far, in a form suitable
3702 to be passed to tsubst.
3704 This is a subroutine of fixup_template_parms. */
3707 fixup_template_parm_index (tree i, tree args, int num_parms)
3709 tree index, decl, type;
3712 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3713 /* Do not fix up the index twice. */
3714 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3717 decl = TEMPLATE_PARM_DECL (i);
3718 type = TREE_TYPE (decl);
3720 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3721 TEMPLATE_PARM_LEVEL (i),
3722 TEMPLATE_PARM_ORIG_LEVEL (i),
3726 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3727 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3729 type = tsubst (type, args, tf_none, NULL_TREE);
3731 TREE_TYPE (decl) = type;
3732 TREE_TYPE (index) = type;
3738 This is a subroutine of fixup_template_parms.
3740 It computes the canonical type of the type of the template
3741 parameter PARM_DESC and update all references to that type so that
3742 they use the newly computed canonical type. No access check is
3743 performed during the fixup. PARM_DESC is a TREE_LIST which
3744 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3745 default argument of the template parm if any. IDX is the index of
3746 the template parameter, starting at 0. NUM_PARMS is the number of
3747 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3748 TREE_VEC containing the full set of template parameters in a form
3749 suitable to be passed to substs functions as their ARGS
3750 argument. This is what current_template_args returns for a given
3751 template. The innermost vector of args in ARGLIST is the set of
3752 template parms that have been fixed up so far. This function adds
3753 the fixed up parameter into that vector. */
3756 fixup_template_parm (tree parm_desc,
3761 tree parm = TREE_VALUE (parm_desc);
3762 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3764 push_deferring_access_checks (dk_no_check);
3766 if (TREE_CODE (parm) == TYPE_DECL)
3768 /* PARM is a template type parameter. Fix up its type, add
3769 the fixed-up template parm to the vector of fixed-up
3770 template parms so far, and substitute the fixed-up
3771 template parms into the default argument of this
3774 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3775 TREE_TYPE (parm) = t;
3777 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3779 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3781 /* PARM is a template template parameter. This is going to
3783 tree tparms, targs, innermost_args, t;
3786 /* First, fix up the parms of the template template parm
3787 because the parms are involved in defining the new canonical
3788 type of the template template parm. */
3790 /* So we need to substitute the template parm types that have
3791 been fixed up so far into the template parms of this template
3792 template parm. E.g, consider this:
3794 template<class T, template<T u> class TT> class S;
3796 In this case we want to substitute T into the
3797 template parameters of TT.
3799 So let's walk the template parms of PARM here, and
3800 tsubst ARGLIST into into each of the template
3803 /* For this substitution we need to build the full set of
3804 template parameters and use that as arguments for the
3805 tsubsting function. */
3806 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3808 /* This will contain the innermost parms of PARM into which
3809 we have substituted so far. */
3810 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3811 targs = add_to_template_args (arglist, innermost_args);
3812 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3816 parameter = TREE_VEC_ELT (tparms, j);
3818 /* INNERMOST_ARGS needs to have at least the same number
3819 of elements as the index PARAMETER, ortherwise
3820 tsubsting into PARAMETER will result in partially
3821 instantiating it, reducing its tempate parm
3822 level. Let's tactically fill INNERMOST_ARGS for that
3824 TREE_VEC_ELT (innermost_args, j) =
3825 template_parm_to_arg (parameter);
3827 fixup_template_parm (parameter, j,
3828 TREE_VEC_LENGTH (tparms),
3832 /* Now fix up the type of the template template parm. */
3834 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3835 TREE_TYPE (parm) = t;
3837 TREE_VEC_ELT (fixedup_args, idx) =
3838 template_parm_to_arg (parm_desc);
3840 else if (TREE_CODE (parm) == PARM_DECL)
3842 /* PARM is a non-type template parameter. We need to:
3844 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3845 proper number of sibling parameters.
3847 * Make lookups of the template parameter return a reference
3848 to the fixed-up index. No lookup should return references
3849 to the former index anymore.
3851 * Substitute the template parms that got fixed up so far
3853 * into the type of PARM. */
3855 tree index = DECL_INITIAL (parm);
3857 /* PUSHED_DECL is the decl added to the symbol table with
3858 the name of the parameter. E,g:
3860 template<class T, T u> //#0
3861 auto my_function(T t) -> decltype(u); //#1
3863 Here, when looking up u at //#1, we get the decl of u
3864 resulting from the declaration in #0. This is what
3865 PUSHED_DECL is. We need to replace the reference to the
3866 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3867 fixed-up TEMPLATE_PARM_INDEX. */
3868 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3870 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3871 fixup the type of PUSHED_DECL as well and luckily
3872 fixup_template_parm_index does it for us too. */
3873 tree fixed_up_index =
3874 fixup_template_parm_index (index, arglist, num_parms);
3876 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3878 /* Add this fixed up PARM to the template parms we've fixed
3879 up so far and use that to substitute the fixed-up
3880 template parms into the type of PARM. */
3881 TREE_VEC_ELT (fixedup_args, idx) =
3882 template_parm_to_arg (parm_desc);
3883 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3884 tf_none, NULL_TREE);
3887 TREE_PURPOSE (parm_desc) =
3888 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3889 arglist, tf_none, parm);
3891 pop_deferring_access_checks ();
3894 /* Walk the current template parms and properly compute the canonical
3895 types of the dependent types created during
3896 cp_parser_template_parameter_list. */
3899 fixup_template_parms (void)
3906 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3907 if (parameter_vec == NULL_TREE)
3910 num_parms = TREE_VEC_LENGTH (parameter_vec);
3912 /* This vector contains the current innermost template parms that
3913 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3914 to be passed to tsubst* functions as their ARGS argument. */
3915 fixedup_args = make_tree_vec (num_parms);
3917 /* This vector contains the full set of template parms in a form
3918 suitable to be passed to substs functions as their ARGS
3920 arglist = current_template_args ();
3921 arglist = add_outermost_template_args (arglist, fixedup_args);
3923 /* Let's do the proper fixup now. */
3924 for (i = 0; i < num_parms; ++i)
3925 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3926 i, num_parms, arglist);
3929 /* end_template_decl is called after a template declaration is seen. */
3932 end_template_decl (void)
3934 reset_specialization ();
3936 if (! processing_template_decl)
3939 /* This matches the pushlevel in begin_template_parm_list. */
3942 --processing_template_decl;
3943 current_template_parms = TREE_CHAIN (current_template_parms);
3946 /* Takes a TREE_LIST representing a template parameter and convert it
3947 into an argument suitable to be passed to the type substitution
3948 functions. Note that If the TREE_LIST contains an error_mark
3949 node, the returned argument is error_mark_node. */
3952 template_parm_to_arg (tree t)
3956 || TREE_CODE (t) != TREE_LIST)
3959 if (error_operand_p (TREE_VALUE (t)))
3960 return error_mark_node;
3964 if (TREE_CODE (t) == TYPE_DECL
3965 || TREE_CODE (t) == TEMPLATE_DECL)
3969 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3971 /* Turn this argument into a TYPE_ARGUMENT_PACK
3972 with a single element, which expands T. */
3973 tree vec = make_tree_vec (1);
3974 #ifdef ENABLE_CHECKING
3975 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3976 (vec, TREE_VEC_LENGTH (vec));
3978 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3980 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3981 SET_ARGUMENT_PACK_ARGS (t, vec);
3986 t = DECL_INITIAL (t);
3988 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3990 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3991 with a single element, which expands T. */
3992 tree vec = make_tree_vec (1);
3993 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3994 #ifdef ENABLE_CHECKING
3995 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3996 (vec, TREE_VEC_LENGTH (vec));
3998 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4000 t = make_node (NONTYPE_ARGUMENT_PACK);
4001 SET_ARGUMENT_PACK_ARGS (t, vec);
4002 TREE_TYPE (t) = type;
4008 /* Within the declaration of a template, return all levels of template
4009 parameters that apply. The template parameters are represented as
4010 a TREE_VEC, in the form documented in cp-tree.h for template
4014 current_template_args (void)
4017 tree args = NULL_TREE;
4018 int length = TMPL_PARMS_DEPTH (current_template_parms);
4021 /* If there is only one level of template parameters, we do not
4022 create a TREE_VEC of TREE_VECs. Instead, we return a single
4023 TREE_VEC containing the arguments. */
4025 args = make_tree_vec (length);
4027 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4029 tree a = copy_node (TREE_VALUE (header));
4032 TREE_TYPE (a) = NULL_TREE;
4033 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4034 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4036 #ifdef ENABLE_CHECKING
4037 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4041 TREE_VEC_ELT (args, --l) = a;
4046 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4047 /* This can happen for template parms of a template template
4050 template<template<class T, class U> class TT> struct S;
4052 Consider the level of the parms of TT; T and U both have
4053 level 2; TT has no template parm of level 1. So in this case
4054 the first element of full_template_args is NULL_TREE. If we
4055 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4056 of 2. This will make tsubst wrongly consider that T and U
4057 have level 1. Instead, let's create a dummy vector as the
4058 first element of full_template_args so that TMPL_ARG_DEPTH
4059 returns the correct depth for args. */
4060 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4064 /* Update the declared TYPE by doing any lookups which were thought to be
4065 dependent, but are not now that we know the SCOPE of the declarator. */
4068 maybe_update_decl_type (tree orig_type, tree scope)
4070 tree type = orig_type;
4072 if (type == NULL_TREE)
4075 if (TREE_CODE (orig_type) == TYPE_DECL)
4076 type = TREE_TYPE (type);
4078 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4079 && dependent_type_p (type)
4080 /* Don't bother building up the args in this case. */
4081 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4083 /* tsubst in the args corresponding to the template parameters,
4084 including auto if present. Most things will be unchanged, but
4085 make_typename_type and tsubst_qualified_id will resolve
4086 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4087 tree args = current_template_args ();
4088 tree auto_node = type_uses_auto (type);
4092 tree auto_vec = make_tree_vec (1);
4093 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4094 args = add_to_template_args (args, auto_vec);
4096 pushed = push_scope (scope);
4097 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4102 if (type == error_mark_node)
4105 if (TREE_CODE (orig_type) == TYPE_DECL)
4107 if (same_type_p (type, TREE_TYPE (orig_type)))
4110 type = TYPE_NAME (type);
4115 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4116 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4117 a member template. Used by push_template_decl below. */
4120 build_template_decl (tree decl, tree parms, bool member_template_p)
4122 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4123 DECL_TEMPLATE_PARMS (tmpl) = parms;
4124 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4125 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4126 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4131 struct template_parm_data
4133 /* The level of the template parameters we are currently
4137 /* The index of the specialization argument we are currently
4141 /* An array whose size is the number of template parameters. The
4142 elements are nonzero if the parameter has been used in any one
4143 of the arguments processed so far. */
4146 /* An array whose size is the number of template arguments. The
4147 elements are nonzero if the argument makes use of template
4148 parameters of this level. */
4149 int* arg_uses_template_parms;
4152 /* Subroutine of push_template_decl used to see if each template
4153 parameter in a partial specialization is used in the explicit
4154 argument list. If T is of the LEVEL given in DATA (which is
4155 treated as a template_parm_data*), then DATA->PARMS is marked
4159 mark_template_parm (tree t, void* data)
4163 struct template_parm_data* tpd = (struct template_parm_data*) data;
4165 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4167 level = TEMPLATE_PARM_LEVEL (t);
4168 idx = TEMPLATE_PARM_IDX (t);
4172 level = TEMPLATE_TYPE_LEVEL (t);
4173 idx = TEMPLATE_TYPE_IDX (t);
4176 if (level == tpd->level)
4178 tpd->parms[idx] = 1;
4179 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4182 /* Return zero so that for_each_template_parm will continue the
4183 traversal of the tree; we want to mark *every* template parm. */
4187 /* Process the partial specialization DECL. */
4190 process_partial_specialization (tree decl)
4192 tree type = TREE_TYPE (decl);
4193 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4194 tree specargs = CLASSTYPE_TI_ARGS (type);
4195 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4196 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4199 int nargs = TREE_VEC_LENGTH (inner_args);
4202 bool did_error_intro = false;
4203 struct template_parm_data tpd;
4204 struct template_parm_data tpd2;
4206 gcc_assert (current_template_parms);
4208 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4209 ntparms = TREE_VEC_LENGTH (inner_parms);
4211 /* We check that each of the template parameters given in the
4212 partial specialization is used in the argument list to the
4213 specialization. For example:
4215 template <class T> struct S;
4216 template <class T> struct S<T*>;
4218 The second declaration is OK because `T*' uses the template
4219 parameter T, whereas
4221 template <class T> struct S<int>;
4223 is no good. Even trickier is:
4234 The S2<T> declaration is actually invalid; it is a
4235 full-specialization. Of course,
4238 struct S2<T (*)(U)>;
4240 or some such would have been OK. */
4241 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4242 tpd.parms = XALLOCAVEC (int, ntparms);
4243 memset (tpd.parms, 0, sizeof (int) * ntparms);
4245 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4246 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4247 for (i = 0; i < nargs; ++i)
4249 tpd.current_arg = i;
4250 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4251 &mark_template_parm,
4254 /*include_nondeduced_p=*/false);
4256 for (i = 0; i < ntparms; ++i)
4257 if (tpd.parms[i] == 0)
4259 /* One of the template parms was not used in the
4261 if (!did_error_intro)
4263 error ("template parameters not used in partial specialization:");
4264 did_error_intro = true;
4267 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4270 if (did_error_intro)
4271 return error_mark_node;
4273 /* [temp.class.spec]
4275 The argument list of the specialization shall not be identical to
4276 the implicit argument list of the primary template. */
4277 if (comp_template_args
4279 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4281 error ("partial specialization %qT does not specialize any template arguments", type);
4283 /* [temp.class.spec]
4285 A partially specialized non-type argument expression shall not
4286 involve template parameters of the partial specialization except
4287 when the argument expression is a simple identifier.
4289 The type of a template parameter corresponding to a specialized
4290 non-type argument shall not be dependent on a parameter of the
4293 Also, we verify that pack expansions only occur at the
4294 end of the argument list. */
4295 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4297 for (i = 0; i < nargs; ++i)
4299 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4300 tree arg = TREE_VEC_ELT (inner_args, i);
4301 tree packed_args = NULL_TREE;
4304 if (ARGUMENT_PACK_P (arg))
4306 /* Extract the arguments from the argument pack. We'll be
4307 iterating over these in the following loop. */
4308 packed_args = ARGUMENT_PACK_ARGS (arg);
4309 len = TREE_VEC_LENGTH (packed_args);
4312 for (j = 0; j < len; j++)
4315 /* Get the Jth argument in the parameter pack. */
4316 arg = TREE_VEC_ELT (packed_args, j);
4318 if (PACK_EXPANSION_P (arg))
4320 /* Pack expansions must come at the end of the
4322 if ((packed_args && j < len - 1)
4323 || (!packed_args && i < nargs - 1))
4325 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4326 error ("parameter pack argument %qE must be at the "
4327 "end of the template argument list", arg);
4329 error ("parameter pack argument %qT must be at the "
4330 "end of the template argument list", arg);
4334 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4335 /* We only care about the pattern. */
4336 arg = PACK_EXPANSION_PATTERN (arg);
4338 if (/* These first two lines are the `non-type' bit. */
4340 && TREE_CODE (arg) != TEMPLATE_DECL
4341 /* This next line is the `argument expression is not just a
4342 simple identifier' condition and also the `specialized
4343 non-type argument' bit. */
4344 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4346 if ((!packed_args && tpd.arg_uses_template_parms[i])
4347 || (packed_args && uses_template_parms (arg)))
4348 error ("template argument %qE involves template parameter(s)",
4352 /* Look at the corresponding template parameter,
4353 marking which template parameters its type depends
4355 tree type = TREE_TYPE (parm);
4359 /* We haven't yet initialized TPD2. Do so now. */
4360 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4361 /* The number of parameters here is the number in the
4362 main template, which, as checked in the assertion
4364 tpd2.parms = XALLOCAVEC (int, nargs);
4366 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4369 /* Mark the template parameters. But this time, we're
4370 looking for the template parameters of the main
4371 template, not in the specialization. */
4372 tpd2.current_arg = i;
4373 tpd2.arg_uses_template_parms[i] = 0;
4374 memset (tpd2.parms, 0, sizeof (int) * nargs);
4375 for_each_template_parm (type,
4376 &mark_template_parm,
4379 /*include_nondeduced_p=*/false);
4381 if (tpd2.arg_uses_template_parms [i])
4383 /* The type depended on some template parameters.
4384 If they are fully specialized in the
4385 specialization, that's OK. */
4388 for (j = 0; j < nargs; ++j)
4389 if (tpd2.parms[j] != 0
4390 && tpd.arg_uses_template_parms [j])
4393 error_n (input_location, count,
4394 "type %qT of template argument %qE depends "
4395 "on a template parameter",
4396 "type %qT of template argument %qE depends "
4397 "on template parameters",
4406 /* We should only get here once. */
4407 gcc_assert (!COMPLETE_TYPE_P (type));
4409 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4410 = tree_cons (specargs, inner_parms,
4411 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4412 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4414 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4415 inst = TREE_CHAIN (inst))
4417 tree inst_type = TREE_VALUE (inst);
4418 if (COMPLETE_TYPE_P (inst_type)
4419 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4421 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4422 if (spec && TREE_TYPE (spec) == type)
4423 permerror (input_location,
4424 "partial specialization of %qT after instantiation "
4425 "of %qT", type, inst_type);
4432 /* Check that a template declaration's use of default arguments and
4433 parameter packs is not invalid. Here, PARMS are the template
4434 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4435 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4439 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4440 declaration (but not a definition); 1 indicates a declaration, 2
4441 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4442 emitted for extraneous default arguments.
4444 Returns TRUE if there were no errors found, FALSE otherwise. */
4447 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4448 int is_partial, int is_friend_decl)
4451 int last_level_to_check;
4453 bool no_errors = true;
4457 A default template-argument shall not be specified in a
4458 function template declaration or a function template definition, nor
4459 in the template-parameter-list of the definition of a member of a
4462 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4463 /* You can't have a function template declaration in a local
4464 scope, nor you can you define a member of a class template in a
4468 if (current_class_type
4469 && !TYPE_BEING_DEFINED (current_class_type)
4470 && DECL_LANG_SPECIFIC (decl)
4471 && DECL_DECLARES_FUNCTION_P (decl)
4472 /* If this is either a friend defined in the scope of the class
4473 or a member function. */
4474 && (DECL_FUNCTION_MEMBER_P (decl)
4475 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4476 : DECL_FRIEND_CONTEXT (decl)
4477 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4479 /* And, if it was a member function, it really was defined in
4480 the scope of the class. */
4481 && (!DECL_FUNCTION_MEMBER_P (decl)
4482 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4483 /* We already checked these parameters when the template was
4484 declared, so there's no need to do it again now. This function
4485 was defined in class scope, but we're processing it's body now
4486 that the class is complete. */
4489 /* Core issue 226 (C++0x only): the following only applies to class
4491 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4495 If a template-parameter has a default template-argument, all
4496 subsequent template-parameters shall have a default
4497 template-argument supplied. */
4498 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4500 tree inner_parms = TREE_VALUE (parm_level);
4501 int ntparms = TREE_VEC_LENGTH (inner_parms);
4502 int seen_def_arg_p = 0;
4505 for (i = 0; i < ntparms; ++i)
4507 tree parm = TREE_VEC_ELT (inner_parms, i);
4509 if (parm == error_mark_node)
4512 if (TREE_PURPOSE (parm))
4514 else if (seen_def_arg_p
4515 && !template_parameter_pack_p (TREE_VALUE (parm)))
4517 error ("no default argument for %qD", TREE_VALUE (parm));
4518 /* For better subsequent error-recovery, we indicate that
4519 there should have been a default argument. */
4520 TREE_PURPOSE (parm) = error_mark_node;
4526 /* Don't complain about an enclosing partial
4528 && parm_level == parms
4529 && TREE_CODE (decl) == TYPE_DECL
4531 && template_parameter_pack_p (TREE_VALUE (parm)))
4533 /* A primary class template can only have one
4534 parameter pack, at the end of the template
4537 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4538 error ("parameter pack %qE must be at the end of the"
4539 " template parameter list", TREE_VALUE (parm));
4541 error ("parameter pack %qT must be at the end of the"
4542 " template parameter list",
4543 TREE_TYPE (TREE_VALUE (parm)));
4545 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4553 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4557 /* For an ordinary class template, default template arguments are
4558 allowed at the innermost level, e.g.:
4559 template <class T = int>
4561 but, in a partial specialization, they're not allowed even
4562 there, as we have in [temp.class.spec]:
4564 The template parameter list of a specialization shall not
4565 contain default template argument values.
4567 So, for a partial specialization, or for a function template
4568 (in C++98/C++03), we look at all of them. */
4571 /* But, for a primary class template that is not a partial
4572 specialization we look at all template parameters except the
4574 parms = TREE_CHAIN (parms);
4576 /* Figure out what error message to issue. */
4577 if (is_friend_decl == 2)
4578 msg = G_("default template arguments may not be used in function template "
4579 "friend re-declaration");
4580 else if (is_friend_decl)
4581 msg = G_("default template arguments may not be used in function template "
4582 "friend declarations");
4583 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4584 msg = G_("default template arguments may not be used in function templates "
4585 "without -std=c++0x or -std=gnu++0x");
4586 else if (is_partial)
4587 msg = G_("default template arguments may not be used in "
4588 "partial specializations");
4590 msg = G_("default argument for template parameter for class enclosing %qD");
4592 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4593 /* If we're inside a class definition, there's no need to
4594 examine the parameters to the class itself. On the one
4595 hand, they will be checked when the class is defined, and,
4596 on the other, default arguments are valid in things like:
4597 template <class T = double>
4598 struct S { template <class U> void f(U); };
4599 Here the default argument for `S' has no bearing on the
4600 declaration of `f'. */
4601 last_level_to_check = template_class_depth (current_class_type) + 1;
4603 /* Check everything. */
4604 last_level_to_check = 0;
4606 for (parm_level = parms;
4607 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4608 parm_level = TREE_CHAIN (parm_level))
4610 tree inner_parms = TREE_VALUE (parm_level);
4614 ntparms = TREE_VEC_LENGTH (inner_parms);
4615 for (i = 0; i < ntparms; ++i)
4617 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4620 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4625 if (is_friend_decl == 2)
4632 /* Clear out the default argument so that we are not
4634 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4638 /* At this point, if we're still interested in issuing messages,
4639 they must apply to classes surrounding the object declared. */
4641 msg = G_("default argument for template parameter for class "
4648 /* Worker for push_template_decl_real, called via
4649 for_each_template_parm. DATA is really an int, indicating the
4650 level of the parameters we are interested in. If T is a template
4651 parameter of that level, return nonzero. */
4654 template_parm_this_level_p (tree t, void* data)
4656 int this_level = *(int *)data;
4659 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4660 level = TEMPLATE_PARM_LEVEL (t);
4662 level = TEMPLATE_TYPE_LEVEL (t);
4663 return level == this_level;
4666 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4667 parameters given by current_template_args, or reuses a
4668 previously existing one, if appropriate. Returns the DECL, or an
4669 equivalent one, if it is replaced via a call to duplicate_decls.
4671 If IS_FRIEND is true, DECL is a friend declaration. */
4674 push_template_decl_real (tree decl, bool is_friend)
4682 int new_template_p = 0;
4683 /* True if the template is a member template, in the sense of
4685 bool member_template_p = false;
4687 if (decl == error_mark_node || !current_template_parms)
4688 return error_mark_node;
4690 /* See if this is a partial specialization. */
4691 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4692 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4693 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4695 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4699 /* For a friend, we want the context of the friend function, not
4700 the type of which it is a friend. */
4701 ctx = CP_DECL_CONTEXT (decl);
4702 else if (CP_DECL_CONTEXT (decl)
4703 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4704 /* In the case of a virtual function, we want the class in which
4706 ctx = CP_DECL_CONTEXT (decl);
4708 /* Otherwise, if we're currently defining some class, the DECL
4709 is assumed to be a member of the class. */
4710 ctx = current_scope ();
4712 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4715 if (!DECL_CONTEXT (decl))
4716 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4718 /* See if this is a primary template. */
4719 if (is_friend && ctx)
4720 /* A friend template that specifies a class context, i.e.
4721 template <typename T> friend void A<T>::f();
4725 primary = template_parm_scope_p ();
4729 if (DECL_CLASS_SCOPE_P (decl))
4730 member_template_p = true;
4731 if (TREE_CODE (decl) == TYPE_DECL
4732 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4734 error ("template class without a name");
4735 return error_mark_node;
4737 else if (TREE_CODE (decl) == FUNCTION_DECL)
4739 if (DECL_DESTRUCTOR_P (decl))
4743 A destructor shall not be a member template. */
4744 error ("destructor %qD declared as member template", decl);
4745 return error_mark_node;
4747 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4748 && (!prototype_p (TREE_TYPE (decl))
4749 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4750 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4751 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4752 == void_list_node)))
4754 /* [basic.stc.dynamic.allocation]
4756 An allocation function can be a function
4757 template. ... Template allocation functions shall
4758 have two or more parameters. */
4759 error ("invalid template declaration of %qD", decl);
4760 return error_mark_node;
4763 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4764 && CLASS_TYPE_P (TREE_TYPE (decl)))
4768 error ("template declaration of %q#D", decl);
4769 return error_mark_node;
4773 /* Check to see that the rules regarding the use of default
4774 arguments are not being violated. */
4775 check_default_tmpl_args (decl, current_template_parms,
4776 primary, is_partial, /*is_friend_decl=*/0);
4778 /* Ensure that there are no parameter packs in the type of this
4779 declaration that have not been expanded. */
4780 if (TREE_CODE (decl) == FUNCTION_DECL)
4782 /* Check each of the arguments individually to see if there are
4783 any bare parameter packs. */
4784 tree type = TREE_TYPE (decl);
4785 tree arg = DECL_ARGUMENTS (decl);
4786 tree argtype = TYPE_ARG_TYPES (type);
4788 while (arg && argtype)
4790 if (!FUNCTION_PARAMETER_PACK_P (arg)
4791 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4793 /* This is a PARM_DECL that contains unexpanded parameter
4794 packs. We have already complained about this in the
4795 check_for_bare_parameter_packs call, so just replace
4796 these types with ERROR_MARK_NODE. */
4797 TREE_TYPE (arg) = error_mark_node;
4798 TREE_VALUE (argtype) = error_mark_node;
4801 arg = DECL_CHAIN (arg);
4802 argtype = TREE_CHAIN (argtype);
4805 /* Check for bare parameter packs in the return type and the
4806 exception specifiers. */
4807 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4808 /* Errors were already issued, set return type to int
4809 as the frontend doesn't expect error_mark_node as
4811 TREE_TYPE (type) = integer_type_node;
4812 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4813 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4815 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4817 TREE_TYPE (decl) = error_mark_node;
4818 return error_mark_node;
4822 return process_partial_specialization (decl);
4824 args = current_template_args ();
4827 || TREE_CODE (ctx) == FUNCTION_DECL
4828 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4829 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4831 if (DECL_LANG_SPECIFIC (decl)
4832 && DECL_TEMPLATE_INFO (decl)
4833 && DECL_TI_TEMPLATE (decl))
4834 tmpl = DECL_TI_TEMPLATE (decl);
4835 /* If DECL is a TYPE_DECL for a class-template, then there won't
4836 be DECL_LANG_SPECIFIC. The information equivalent to
4837 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4838 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4839 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4840 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4842 /* Since a template declaration already existed for this
4843 class-type, we must be redeclaring it here. Make sure
4844 that the redeclaration is valid. */
4845 redeclare_class_template (TREE_TYPE (decl),
4846 current_template_parms);
4847 /* We don't need to create a new TEMPLATE_DECL; just use the
4848 one we already had. */
4849 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4853 tmpl = build_template_decl (decl, current_template_parms,
4857 if (DECL_LANG_SPECIFIC (decl)
4858 && DECL_TEMPLATE_SPECIALIZATION (decl))
4860 /* A specialization of a member template of a template
4862 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4863 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4864 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4870 tree a, t, current, parms;
4872 tree tinfo = get_template_info (decl);
4876 error ("template definition of non-template %q#D", decl);
4877 return error_mark_node;
4880 tmpl = TI_TEMPLATE (tinfo);
4882 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4883 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4884 && DECL_TEMPLATE_SPECIALIZATION (decl)
4885 && DECL_MEMBER_TEMPLATE_P (tmpl))
4889 /* The declaration is a specialization of a member
4890 template, declared outside the class. Therefore, the
4891 innermost template arguments will be NULL, so we
4892 replace them with the arguments determined by the
4893 earlier call to check_explicit_specialization. */
4894 args = DECL_TI_ARGS (decl);
4897 = build_template_decl (decl, current_template_parms,
4899 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4900 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4901 DECL_TI_TEMPLATE (decl) = new_tmpl;
4902 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4903 DECL_TEMPLATE_INFO (new_tmpl)
4904 = build_template_info (tmpl, args);
4906 register_specialization (new_tmpl,
4907 most_general_template (tmpl),
4913 /* Make sure the template headers we got make sense. */
4915 parms = DECL_TEMPLATE_PARMS (tmpl);
4916 i = TMPL_PARMS_DEPTH (parms);
4917 if (TMPL_ARGS_DEPTH (args) != i)
4919 error ("expected %d levels of template parms for %q#D, got %d",
4920 i, decl, TMPL_ARGS_DEPTH (args));
4923 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4925 a = TMPL_ARGS_LEVEL (args, i);
4926 t = INNERMOST_TEMPLATE_PARMS (parms);
4928 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4930 if (current == decl)
4931 error ("got %d template parameters for %q#D",
4932 TREE_VEC_LENGTH (a), decl);
4934 error ("got %d template parameters for %q#T",
4935 TREE_VEC_LENGTH (a), current);
4936 error (" but %d required", TREE_VEC_LENGTH (t));
4937 return error_mark_node;
4940 if (current == decl)
4942 else if (current == NULL_TREE)
4943 /* Can happen in erroneous input. */
4946 current = (TYPE_P (current)
4947 ? TYPE_CONTEXT (current)
4948 : DECL_CONTEXT (current));
4951 /* Check that the parms are used in the appropriate qualifying scopes
4952 in the declarator. */
4953 if (!comp_template_args
4955 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4958 template arguments to %qD do not match original template %qD",
4959 decl, DECL_TEMPLATE_RESULT (tmpl));
4960 if (!uses_template_parms (TI_ARGS (tinfo)))
4961 inform (input_location, "use template<> for an explicit specialization");
4962 /* Avoid crash in import_export_decl. */
4963 DECL_INTERFACE_KNOWN (decl) = 1;
4964 return error_mark_node;
4968 DECL_TEMPLATE_RESULT (tmpl) = decl;
4969 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4971 /* Push template declarations for global functions and types. Note
4972 that we do not try to push a global template friend declared in a
4973 template class; such a thing may well depend on the template
4974 parameters of the class. */
4975 if (new_template_p && !ctx
4976 && !(is_friend && template_class_depth (current_class_type) > 0))
4978 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4979 if (tmpl == error_mark_node)
4980 return error_mark_node;
4982 /* Hide template friend classes that haven't been declared yet. */
4983 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4985 DECL_ANTICIPATED (tmpl) = 1;
4986 DECL_FRIEND_P (tmpl) = 1;
4992 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4995 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4996 if (DECL_CONV_FN_P (tmpl))
4998 int depth = TMPL_PARMS_DEPTH (parms);
5000 /* It is a conversion operator. See if the type converted to
5001 depends on innermost template operands. */
5003 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5005 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5008 /* Give template template parms a DECL_CONTEXT of the template
5009 for which they are a parameter. */
5010 parms = INNERMOST_TEMPLATE_PARMS (parms);
5011 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5013 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5014 if (TREE_CODE (parm) == TEMPLATE_DECL)
5015 DECL_CONTEXT (parm) = tmpl;
5019 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5020 back to its most general template. If TMPL is a specialization,
5021 ARGS may only have the innermost set of arguments. Add the missing
5022 argument levels if necessary. */
5023 if (DECL_TEMPLATE_INFO (tmpl))
5024 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5026 info = build_template_info (tmpl, args);
5028 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5029 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5030 else if (DECL_LANG_SPECIFIC (decl))
5031 DECL_TEMPLATE_INFO (decl) = info;
5033 return DECL_TEMPLATE_RESULT (tmpl);
5037 push_template_decl (tree decl)
5039 return push_template_decl_real (decl, false);
5042 /* Called when a class template TYPE is redeclared with the indicated
5043 template PARMS, e.g.:
5045 template <class T> struct S;
5046 template <class T> struct S {}; */
5049 redeclare_class_template (tree type, tree parms)
5055 if (!TYPE_TEMPLATE_INFO (type))
5057 error ("%qT is not a template type", type);
5061 tmpl = TYPE_TI_TEMPLATE (type);
5062 if (!PRIMARY_TEMPLATE_P (tmpl))
5063 /* The type is nested in some template class. Nothing to worry
5064 about here; there are no new template parameters for the nested
5070 error ("template specifiers not specified in declaration of %qD",
5075 parms = INNERMOST_TEMPLATE_PARMS (parms);
5076 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5078 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5080 error_n (input_location, TREE_VEC_LENGTH (parms),
5081 "redeclared with %d template parameter",
5082 "redeclared with %d template parameters",
5083 TREE_VEC_LENGTH (parms));
5084 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5085 "previous declaration %q+D used %d template parameter",
5086 "previous declaration %q+D used %d template parameters",
5087 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5091 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5098 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5099 || TREE_VEC_ELT (parms, i) == error_mark_node)
5102 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5103 if (tmpl_parm == error_mark_node)
5106 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5107 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5108 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5110 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5112 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5113 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5114 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5115 || (TREE_CODE (tmpl_parm) != PARM_DECL
5116 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5117 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5118 || (TREE_CODE (tmpl_parm) == PARM_DECL
5119 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5120 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5122 error ("template parameter %q+#D", tmpl_parm);
5123 error ("redeclared here as %q#D", parm);
5127 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5129 /* We have in [temp.param]:
5131 A template-parameter may not be given default arguments
5132 by two different declarations in the same scope. */
5133 error_at (input_location, "redefinition of default argument for %q#D", parm);
5134 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5135 "original definition appeared here");
5139 if (parm_default != NULL_TREE)
5140 /* Update the previous template parameters (which are the ones
5141 that will really count) with the new default value. */
5142 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5143 else if (tmpl_default != NULL_TREE)
5144 /* Update the new parameters, too; they'll be used as the
5145 parameters for any members. */
5146 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5152 /* Simplify EXPR if it is a non-dependent expression. Returns the
5153 (possibly simplified) expression. */
5156 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5158 if (expr == NULL_TREE)
5161 /* If we're in a template, but EXPR isn't value dependent, simplify
5162 it. We're supposed to treat:
5164 template <typename T> void f(T[1 + 1]);
5165 template <typename T> void f(T[2]);
5167 as two declarations of the same function, for example. */
5168 if (processing_template_decl
5169 && !type_dependent_expression_p (expr)
5170 && potential_constant_expression (expr)
5171 && !value_dependent_expression_p (expr))
5173 HOST_WIDE_INT saved_processing_template_decl;
5175 saved_processing_template_decl = processing_template_decl;
5176 processing_template_decl = 0;
5177 expr = tsubst_copy_and_build (expr,
5180 /*in_decl=*/NULL_TREE,
5181 /*function_p=*/false,
5182 /*integral_constant_expression_p=*/true);
5183 processing_template_decl = saved_processing_template_decl;
5189 fold_non_dependent_expr (tree expr)
5191 return fold_non_dependent_expr_sfinae (expr, tf_error);
5194 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5195 must be a function or a pointer-to-function type, as specified
5196 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5197 and check that the resulting function has external linkage. */
5200 convert_nontype_argument_function (tree type, tree expr)
5205 fn = instantiate_type (type, fns, tf_none);
5206 if (fn == error_mark_node)
5207 return error_mark_node;
5210 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5211 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5212 if (TREE_CODE (fn_no_ptr) == BASELINK)
5213 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5215 /* [temp.arg.nontype]/1
5217 A template-argument for a non-type, non-template template-parameter
5220 -- the address of an object or function with external linkage. */
5221 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5223 error ("%qE is not a valid template argument for type %qT "
5224 "because function %qD has not external linkage",
5225 expr, type, fn_no_ptr);
5232 /* Subroutine of convert_nontype_argument.
5233 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5234 Emit an error otherwise. */
5237 check_valid_ptrmem_cst_expr (tree type, tree expr,
5238 tsubst_flags_t complain)
5241 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5243 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5245 if (complain & tf_error)
5247 error ("%qE is not a valid template argument for type %qT",
5249 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5254 /* Returns TRUE iff the address of OP is value-dependent.
5256 14.6.2.4 [temp.dep.temp]:
5257 A non-integral non-type template-argument is dependent if its type is
5258 dependent or it has either of the following forms
5261 and contains a nested-name-specifier which specifies a class-name that
5262 names a dependent type.
5264 We generalize this to just say that the address of a member of a
5265 dependent class is value-dependent; the above doesn't cover the
5266 address of a static data member named with an unqualified-id. */
5269 has_value_dependent_address (tree op)
5271 /* We could use get_inner_reference here, but there's no need;
5272 this is only relevant for template non-type arguments, which
5273 can only be expressed as &id-expression. */
5276 tree ctx = CP_DECL_CONTEXT (op);
5277 if (TYPE_P (ctx) && dependent_type_p (ctx))
5284 /* The next set of functions are used for providing helpful explanatory
5285 diagnostics for failed overload resolution. Their messages should be
5286 indented by two spaces for consistency with the messages in
5290 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5296 unify_parameter_deduction_failure (bool explain_p, tree parm)
5299 inform (input_location,
5300 " couldn't deduce template parameter %qD", parm);
5305 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5311 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5314 inform (input_location,
5315 " types %qT and %qT have incompatible cv-qualifiers",
5321 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5324 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5329 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5332 inform (input_location,
5333 " template parameter %qD is not a parameter pack, but "
5340 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5343 inform (input_location,
5344 " template argument %qE does not match "
5345 "pointer-to-member constant %qE",
5351 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5354 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5359 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5362 inform (input_location,
5363 " inconsistent parameter pack deduction with %qT and %qT",
5369 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5372 inform (input_location,
5373 " deduced conflicting types for parameter %qT (%qT and %qT)",
5374 parm, first, second);
5379 unify_vla_arg (bool explain_p, tree arg)
5382 inform (input_location,
5383 " variable-sized array type %qT is not "
5384 "a valid template argument",
5390 unify_method_type_error (bool explain_p, tree arg)
5393 inform (input_location,
5394 " member function type %qT is not a valid template argument",
5400 unify_arity (bool explain_p, int have, int wanted)
5403 inform_n (input_location, wanted,
5404 " candidate expects %d argument, %d provided",
5405 " candidate expects %d arguments, %d provided",
5411 unify_too_many_arguments (bool explain_p, int have, int wanted)
5413 return unify_arity (explain_p, have, wanted);
5417 unify_too_few_arguments (bool explain_p, int have, int wanted)
5419 return unify_arity (explain_p, have, wanted);
5423 unify_arg_conversion (bool explain_p, tree to_type,
5424 tree from_type, tree arg)
5427 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5428 arg, from_type, to_type);
5433 unify_no_common_base (bool explain_p, enum template_base_result r,
5434 tree parm, tree arg)
5439 case tbr_ambiguous_baseclass:
5440 inform (input_location, " %qT is an ambiguous base class of %qT",
5444 inform (input_location, " %qT is not derived from %qT", arg, parm);
5451 unify_inconsistent_template_template_parameters (bool explain_p)
5454 inform (input_location,
5455 " template parameters of a template template argument are "
5456 "inconsistent with other deduced template arguments");
5461 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5464 inform (input_location,
5465 " can't deduce a template for %qT from non-template type %qT",
5471 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5474 inform (input_location,
5475 " template argument %qE does not match %qD", arg, parm);
5480 unify_overload_resolution_failure (bool explain_p, tree arg)
5483 inform (input_location,
5484 " could not resolve address from overloaded function %qE",
5489 /* Attempt to convert the non-type template parameter EXPR to the
5490 indicated TYPE. If the conversion is successful, return the
5491 converted value. If the conversion is unsuccessful, return
5492 NULL_TREE if we issued an error message, or error_mark_node if we
5493 did not. We issue error messages for out-and-out bad template
5494 parameters, but not simply because the conversion failed, since we
5495 might be just trying to do argument deduction. Both TYPE and EXPR
5496 must be non-dependent.
5498 The conversion follows the special rules described in
5499 [temp.arg.nontype], and it is much more strict than an implicit
5502 This function is called twice for each template argument (see
5503 lookup_template_class for a more accurate description of this
5504 problem). This means that we need to handle expressions which
5505 are not valid in a C++ source, but can be created from the
5506 first call (for instance, casts to perform conversions). These
5507 hacks can go away after we fix the double coercion problem. */
5510 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5514 /* Detect immediately string literals as invalid non-type argument.
5515 This special-case is not needed for correctness (we would easily
5516 catch this later), but only to provide better diagnostic for this
5517 common user mistake. As suggested by DR 100, we do not mention
5518 linkage issues in the diagnostic as this is not the point. */
5519 /* FIXME we're making this OK. */
5520 if (TREE_CODE (expr) == STRING_CST)
5522 if (complain & tf_error)
5523 error ("%qE is not a valid template argument for type %qT "
5524 "because string literals can never be used in this context",
5529 /* Add the ADDR_EXPR now for the benefit of
5530 value_dependent_expression_p. */
5531 if (TYPE_PTROBV_P (type)
5532 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5533 expr = decay_conversion (expr);
5535 /* If we are in a template, EXPR may be non-dependent, but still
5536 have a syntactic, rather than semantic, form. For example, EXPR
5537 might be a SCOPE_REF, rather than the VAR_DECL to which the
5538 SCOPE_REF refers. Preserving the qualifying scope is necessary
5539 so that access checking can be performed when the template is
5540 instantiated -- but here we need the resolved form so that we can
5541 convert the argument. */
5542 if (TYPE_REF_OBJ_P (type)
5543 && has_value_dependent_address (expr))
5544 /* If we want the address and it's value-dependent, don't fold. */;
5545 else if (!type_unknown_p (expr))
5546 expr = fold_non_dependent_expr_sfinae (expr, complain);
5547 if (error_operand_p (expr))
5548 return error_mark_node;
5549 expr_type = TREE_TYPE (expr);
5550 if (TREE_CODE (type) == REFERENCE_TYPE)
5551 expr = mark_lvalue_use (expr);
5553 expr = mark_rvalue_use (expr);
5555 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5556 to a non-type argument of "nullptr". */
5557 if (expr == nullptr_node
5558 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5559 expr = convert (type, expr);
5561 /* In C++11, non-type template arguments can be arbitrary constant
5562 expressions. But don't fold a PTRMEM_CST to a CONSTRUCTOR yet. */
5563 if (cxx_dialect >= cxx0x && TREE_CODE (expr) != PTRMEM_CST)
5564 expr = maybe_constant_value (expr);
5566 /* HACK: Due to double coercion, we can get a
5567 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5568 which is the tree that we built on the first call (see
5569 below when coercing to reference to object or to reference to
5570 function). We just strip everything and get to the arg.
5571 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5573 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5575 tree probe_type, probe = expr;
5576 if (REFERENCE_REF_P (probe))
5577 probe = TREE_OPERAND (probe, 0);
5578 probe_type = TREE_TYPE (probe);
5579 if (TREE_CODE (probe) == NOP_EXPR)
5581 /* ??? Maybe we could use convert_from_reference here, but we
5582 would need to relax its constraints because the NOP_EXPR
5583 could actually change the type to something more cv-qualified,
5584 and this is not folded by convert_from_reference. */
5585 tree addr = TREE_OPERAND (probe, 0);
5586 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5587 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5588 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5589 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5590 (TREE_TYPE (probe_type),
5591 TREE_TYPE (TREE_TYPE (addr))));
5593 expr = TREE_OPERAND (addr, 0);
5594 expr_type = TREE_TYPE (expr);
5598 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5599 parameter is a pointer to object, through decay and
5600 qualification conversion. Let's strip everything. */
5601 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5604 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5605 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5606 /* Skip the ADDR_EXPR only if it is part of the decay for
5607 an array. Otherwise, it is part of the original argument
5608 in the source code. */
5609 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5610 expr = TREE_OPERAND (expr, 0);
5611 expr_type = TREE_TYPE (expr);
5614 /* [temp.arg.nontype]/5, bullet 1
5616 For a non-type template-parameter of integral or enumeration type,
5617 integral promotions (_conv.prom_) and integral conversions
5618 (_conv.integral_) are applied. */
5619 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5621 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5622 t = maybe_constant_value (t);
5623 if (t != error_mark_node)
5626 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5627 return error_mark_node;
5629 /* Notice that there are constant expressions like '4 % 0' which
5630 do not fold into integer constants. */
5631 if (TREE_CODE (expr) != INTEGER_CST)
5633 if (complain & tf_error)
5635 int errs = errorcount, warns = warningcount;
5636 expr = cxx_constant_value (expr);
5637 if (errorcount > errs || warningcount > warns)
5638 inform (EXPR_LOC_OR_HERE (expr),
5639 "in template argument for type %qT ", type);
5640 if (expr == error_mark_node)
5642 /* else cxx_constant_value complained but gave us
5643 a real constant, so go ahead. */
5644 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5650 /* [temp.arg.nontype]/5, bullet 2
5652 For a non-type template-parameter of type pointer to object,
5653 qualification conversions (_conv.qual_) and the array-to-pointer
5654 conversion (_conv.array_) are applied. */
5655 else if (TYPE_PTROBV_P (type))
5657 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5659 A template-argument for a non-type, non-template template-parameter
5660 shall be one of: [...]
5662 -- the name of a non-type template-parameter;
5663 -- the address of an object or function with external linkage, [...]
5664 expressed as "& id-expression" where the & is optional if the name
5665 refers to a function or array, or if the corresponding
5666 template-parameter is a reference.
5668 Here, we do not care about functions, as they are invalid anyway
5669 for a parameter of type pointer-to-object. */
5671 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5672 /* Non-type template parameters are OK. */
5674 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5675 /* Null pointer values are OK in C++11. */;
5676 else if (TREE_CODE (expr) != ADDR_EXPR
5677 && TREE_CODE (expr_type) != ARRAY_TYPE)
5679 if (TREE_CODE (expr) == VAR_DECL)
5681 error ("%qD is not a valid template argument "
5682 "because %qD is a variable, not the address of "
5687 /* Other values, like integer constants, might be valid
5688 non-type arguments of some other type. */
5689 return error_mark_node;
5695 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5696 ? TREE_OPERAND (expr, 0) : expr);
5697 if (TREE_CODE (decl) != VAR_DECL)
5699 error ("%qE is not a valid template argument of type %qT "
5700 "because %qE is not a variable",
5704 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5706 error ("%qE is not a valid template argument of type %qT "
5707 "because %qD does not have external linkage",
5713 expr = decay_conversion (expr);
5714 if (expr == error_mark_node)
5715 return error_mark_node;
5717 expr = perform_qualification_conversions (type, expr);
5718 if (expr == error_mark_node)
5719 return error_mark_node;
5721 /* [temp.arg.nontype]/5, bullet 3
5723 For a non-type template-parameter of type reference to object, no
5724 conversions apply. The type referred to by the reference may be more
5725 cv-qualified than the (otherwise identical) type of the
5726 template-argument. The template-parameter is bound directly to the
5727 template-argument, which must be an lvalue. */
5728 else if (TYPE_REF_OBJ_P (type))
5730 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5732 return error_mark_node;
5734 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5736 error ("%qE is not a valid template argument for type %qT "
5737 "because of conflicts in cv-qualification", expr, type);
5741 if (!real_lvalue_p (expr))
5743 error ("%qE is not a valid template argument for type %qT "
5744 "because it is not an lvalue", expr, type);
5748 /* [temp.arg.nontype]/1
5750 A template-argument for a non-type, non-template template-parameter
5751 shall be one of: [...]
5753 -- the address of an object or function with external linkage. */
5754 if (TREE_CODE (expr) == INDIRECT_REF
5755 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5757 expr = TREE_OPERAND (expr, 0);
5760 error ("%q#D is not a valid template argument for type %qT "
5761 "because a reference variable does not have a constant "
5762 "address", expr, type);
5769 error ("%qE is not a valid template argument for type %qT "
5770 "because it is not an object with external linkage",
5775 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5777 error ("%qE is not a valid template argument for type %qT "
5778 "because object %qD has not external linkage",
5783 expr = build_nop (type, build_address (expr));
5785 /* [temp.arg.nontype]/5, bullet 4
5787 For a non-type template-parameter of type pointer to function, only
5788 the function-to-pointer conversion (_conv.func_) is applied. If the
5789 template-argument represents a set of overloaded functions (or a
5790 pointer to such), the matching function is selected from the set
5792 else if (TYPE_PTRFN_P (type))
5794 /* If the argument is a template-id, we might not have enough
5795 context information to decay the pointer. */
5796 if (!type_unknown_p (expr_type))
5798 expr = decay_conversion (expr);
5799 if (expr == error_mark_node)
5800 return error_mark_node;
5803 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5804 /* Null pointer values are OK in C++11. */
5805 return perform_qualification_conversions (type, expr);
5807 expr = convert_nontype_argument_function (type, expr);
5808 if (!expr || expr == error_mark_node)
5811 if (TREE_CODE (expr) != ADDR_EXPR)
5813 error ("%qE is not a valid template argument for type %qT", expr, type);
5814 error ("it must be the address of a function with external linkage");
5818 /* [temp.arg.nontype]/5, bullet 5
5820 For a non-type template-parameter of type reference to function, no
5821 conversions apply. If the template-argument represents a set of
5822 overloaded functions, the matching function is selected from the set
5824 else if (TYPE_REFFN_P (type))
5826 if (TREE_CODE (expr) == ADDR_EXPR)
5828 error ("%qE is not a valid template argument for type %qT "
5829 "because it is a pointer", expr, type);
5830 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5834 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5835 if (!expr || expr == error_mark_node)
5838 expr = build_nop (type, build_address (expr));
5840 /* [temp.arg.nontype]/5, bullet 6
5842 For a non-type template-parameter of type pointer to member function,
5843 no conversions apply. If the template-argument represents a set of
5844 overloaded member functions, the matching member function is selected
5845 from the set (_over.over_). */
5846 else if (TYPE_PTRMEMFUNC_P (type))
5848 expr = instantiate_type (type, expr, tf_none);
5849 if (expr == error_mark_node)
5850 return error_mark_node;
5852 /* [temp.arg.nontype] bullet 1 says the pointer to member
5853 expression must be a pointer-to-member constant. */
5854 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5855 return error_mark_node;
5857 /* There is no way to disable standard conversions in
5858 resolve_address_of_overloaded_function (called by
5859 instantiate_type). It is possible that the call succeeded by
5860 converting &B::I to &D::I (where B is a base of D), so we need
5861 to reject this conversion here.
5863 Actually, even if there was a way to disable standard conversions,
5864 it would still be better to reject them here so that we can
5865 provide a superior diagnostic. */
5866 if (!same_type_p (TREE_TYPE (expr), type))
5868 error ("%qE is not a valid template argument for type %qT "
5869 "because it is of type %qT", expr, type,
5871 /* If we are just one standard conversion off, explain. */
5872 if (can_convert (type, TREE_TYPE (expr)))
5873 inform (input_location,
5874 "standard conversions are not allowed in this context");
5878 /* [temp.arg.nontype]/5, bullet 7
5880 For a non-type template-parameter of type pointer to data member,
5881 qualification conversions (_conv.qual_) are applied. */
5882 else if (TYPE_PTRMEM_P (type))
5884 /* [temp.arg.nontype] bullet 1 says the pointer to member
5885 expression must be a pointer-to-member constant. */
5886 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5887 return error_mark_node;
5889 expr = perform_qualification_conversions (type, expr);
5890 if (expr == error_mark_node)
5893 /* A template non-type parameter must be one of the above. */
5897 /* Sanity check: did we actually convert the argument to the
5899 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5900 (type, TREE_TYPE (expr)));
5904 /* Subroutine of coerce_template_template_parms, which returns 1 if
5905 PARM_PARM and ARG_PARM match using the rule for the template
5906 parameters of template template parameters. Both PARM and ARG are
5907 template parameters; the rest of the arguments are the same as for
5908 coerce_template_template_parms.
5911 coerce_template_template_parm (tree parm,
5913 tsubst_flags_t complain,
5917 if (arg == NULL_TREE || arg == error_mark_node
5918 || parm == NULL_TREE || parm == error_mark_node)
5921 if (TREE_CODE (arg) != TREE_CODE (parm))
5924 switch (TREE_CODE (parm))
5927 /* We encounter instantiations of templates like
5928 template <template <template <class> class> class TT>
5931 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5932 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5934 if (!coerce_template_template_parms
5935 (parmparm, argparm, complain, in_decl, outer_args))
5941 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5942 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5943 /* Argument is a parameter pack but parameter is not. */
5948 /* The tsubst call is used to handle cases such as
5950 template <int> class C {};
5951 template <class T, template <T> class TT> class D {};
5954 i.e. the parameter list of TT depends on earlier parameters. */
5955 if (!uses_template_parms (TREE_TYPE (arg))
5957 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5961 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5962 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5963 /* Argument is a parameter pack but parameter is not. */
5976 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5977 template template parameters. Both PARM_PARMS and ARG_PARMS are
5978 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5981 Consider the example:
5982 template <class T> class A;
5983 template<template <class U> class TT> class B;
5985 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5986 the parameters to A, and OUTER_ARGS contains A. */
5989 coerce_template_template_parms (tree parm_parms,
5991 tsubst_flags_t complain,
5995 int nparms, nargs, i;
5999 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6000 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6002 nparms = TREE_VEC_LENGTH (parm_parms);
6003 nargs = TREE_VEC_LENGTH (arg_parms);
6005 /* Determine whether we have a parameter pack at the end of the
6006 template template parameter's template parameter list. */
6007 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6009 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6011 if (parm == error_mark_node)
6014 switch (TREE_CODE (parm))
6018 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6023 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6033 && !(variadic_p && nargs >= nparms - 1))
6036 /* Check all of the template parameters except the parameter pack at
6037 the end (if any). */
6038 for (i = 0; i < nparms - variadic_p; ++i)
6040 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6041 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6044 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6045 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6047 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6055 /* Check each of the template parameters in the template
6056 argument against the template parameter pack at the end of
6057 the template template parameter. */
6058 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6061 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6063 for (; i < nargs; ++i)
6065 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6068 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6070 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6079 /* Verifies that the deduced template arguments (in TARGS) for the
6080 template template parameters (in TPARMS) represent valid bindings,
6081 by comparing the template parameter list of each template argument
6082 to the template parameter list of its corresponding template
6083 template parameter, in accordance with DR150. This
6084 routine can only be called after all template arguments have been
6085 deduced. It will return TRUE if all of the template template
6086 parameter bindings are okay, FALSE otherwise. */
6088 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6090 int i, ntparms = TREE_VEC_LENGTH (tparms);
6093 /* We're dealing with template parms in this process. */
6094 ++processing_template_decl;
6096 targs = INNERMOST_TEMPLATE_ARGS (targs);
6098 for (i = 0; i < ntparms; ++i)
6100 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6101 tree targ = TREE_VEC_ELT (targs, i);
6103 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6105 tree packed_args = NULL_TREE;
6108 if (ARGUMENT_PACK_P (targ))
6110 /* Look inside the argument pack. */
6111 packed_args = ARGUMENT_PACK_ARGS (targ);
6112 len = TREE_VEC_LENGTH (packed_args);
6115 for (idx = 0; idx < len; ++idx)
6117 tree targ_parms = NULL_TREE;
6120 /* Extract the next argument from the argument
6122 targ = TREE_VEC_ELT (packed_args, idx);
6124 if (PACK_EXPANSION_P (targ))
6125 /* Look at the pattern of the pack expansion. */
6126 targ = PACK_EXPANSION_PATTERN (targ);
6128 /* Extract the template parameters from the template
6130 if (TREE_CODE (targ) == TEMPLATE_DECL)
6131 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6132 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6133 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6135 /* Verify that we can coerce the template template
6136 parameters from the template argument to the template
6137 parameter. This requires an exact match. */
6139 && !coerce_template_template_parms
6140 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6155 --processing_template_decl;
6159 /* Since type attributes aren't mangled, we need to strip them from
6160 template type arguments. */
6163 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6166 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6168 mv = TYPE_MAIN_VARIANT (arg);
6169 arg = strip_typedefs (arg);
6170 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6171 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6173 if (complain & tf_warning)
6174 warning (0, "ignoring attributes on template argument %qT", arg);
6175 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6176 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6181 /* Convert the indicated template ARG as necessary to match the
6182 indicated template PARM. Returns the converted ARG, or
6183 error_mark_node if the conversion was unsuccessful. Error and
6184 warning messages are issued under control of COMPLAIN. This
6185 conversion is for the Ith parameter in the parameter list. ARGS is
6186 the full set of template arguments deduced so far. */
6189 convert_template_argument (tree parm,
6192 tsubst_flags_t complain,
6198 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6200 if (TREE_CODE (arg) == TREE_LIST
6201 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6203 /* The template argument was the name of some
6204 member function. That's usually
6205 invalid, but static members are OK. In any
6206 case, grab the underlying fields/functions
6207 and issue an error later if required. */
6208 orig_arg = TREE_VALUE (arg);
6209 TREE_TYPE (arg) = unknown_type_node;
6214 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6215 requires_type = (TREE_CODE (parm) == TYPE_DECL
6216 || requires_tmpl_type);
6218 /* When determining whether an argument pack expansion is a template,
6219 look at the pattern. */
6220 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6221 arg = PACK_EXPANSION_PATTERN (arg);
6223 /* Deal with an injected-class-name used as a template template arg. */
6224 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6226 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6227 if (TREE_CODE (t) == TEMPLATE_DECL)
6229 if (cxx_dialect >= cxx0x)
6230 /* OK under DR 1004. */;
6231 else if (complain & tf_warning_or_error)
6232 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6233 " used as template template argument", TYPE_NAME (arg));
6234 else if (flag_pedantic_errors)
6242 ((TREE_CODE (arg) == TEMPLATE_DECL
6243 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6244 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6245 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6248 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6249 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6250 arg = TYPE_STUB_DECL (arg);
6252 is_type = TYPE_P (arg) || is_tmpl_type;
6254 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6255 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6257 permerror (input_location, "to refer to a type member of a template parameter, "
6258 "use %<typename %E%>", orig_arg);
6260 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6261 TREE_OPERAND (arg, 1),
6263 complain & tf_error);
6267 if (is_type != requires_type)
6271 if (complain & tf_error)
6273 error ("type/value mismatch at argument %d in template "
6274 "parameter list for %qD",
6277 error (" expected a constant of type %qT, got %qT",
6279 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6280 else if (requires_tmpl_type)
6281 error (" expected a class template, got %qE", orig_arg);
6283 error (" expected a type, got %qE", orig_arg);
6286 return error_mark_node;
6288 if (is_tmpl_type ^ requires_tmpl_type)
6290 if (in_decl && (complain & tf_error))
6292 error ("type/value mismatch at argument %d in template "
6293 "parameter list for %qD",
6296 error (" expected a type, got %qT", DECL_NAME (arg));
6298 error (" expected a class template, got %qT", orig_arg);
6300 return error_mark_node;
6305 if (requires_tmpl_type)
6307 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6308 /* The number of argument required is not known yet.
6309 Just accept it for now. */
6310 val = TREE_TYPE (arg);
6313 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6316 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6318 if (coerce_template_template_parms (parmparm, argparm,
6324 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6326 if (val != error_mark_node)
6328 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6329 val = TREE_TYPE (val);
6330 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6331 val = make_pack_expansion (val);
6336 if (in_decl && (complain & tf_error))
6338 error ("type/value mismatch at argument %d in "
6339 "template parameter list for %qD",
6341 error (" expected a template of type %qD, got %qT",
6345 val = error_mark_node;
6351 /* We only form one instance of each template specialization.
6352 Therefore, if we use a non-canonical variant (i.e., a
6353 typedef), any future messages referring to the type will use
6354 the typedef, which is confusing if those future uses do not
6355 themselves also use the typedef. */
6357 val = canonicalize_type_argument (val, complain);
6361 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6363 if (invalid_nontype_parm_type_p (t, complain))
6364 return error_mark_node;
6366 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6368 if (same_type_p (t, TREE_TYPE (orig_arg)))
6372 /* Not sure if this is reachable, but it doesn't hurt
6374 error ("type mismatch in nontype parameter pack");
6375 val = error_mark_node;
6378 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6379 /* We used to call digest_init here. However, digest_init
6380 will report errors, which we don't want when complain
6381 is zero. More importantly, digest_init will try too
6382 hard to convert things: for example, `0' should not be
6383 converted to pointer type at this point according to
6384 the standard. Accepting this is not merely an
6385 extension, since deciding whether or not these
6386 conversions can occur is part of determining which
6387 function template to call, or whether a given explicit
6388 argument specification is valid. */
6389 val = convert_nontype_argument (t, orig_arg, complain);
6393 if (val == NULL_TREE)
6394 val = error_mark_node;
6395 else if (val == error_mark_node && (complain & tf_error))
6396 error ("could not convert template argument %qE to %qT", orig_arg, t);
6398 if (TREE_CODE (val) == SCOPE_REF)
6400 /* Strip typedefs from the SCOPE_REF. */
6401 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6402 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6404 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6405 QUALIFIED_NAME_IS_TEMPLATE (val));
6412 /* Coerces the remaining template arguments in INNER_ARGS (from
6413 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6414 Returns the coerced argument pack. PARM_IDX is the position of this
6415 parameter in the template parameter list. ARGS is the original
6416 template argument list. */
6418 coerce_template_parameter_pack (tree parms,
6426 tsubst_flags_t complain)
6428 tree parm = TREE_VEC_ELT (parms, parm_idx);
6429 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6432 tree packed_types = NULL_TREE;
6434 if (arg_idx > nargs)
6437 packed_args = make_tree_vec (nargs - arg_idx);
6439 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6440 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6442 /* When the template parameter is a non-type template
6443 parameter pack whose type uses parameter packs, we need
6444 to look at each of the template arguments
6445 separately. Build a vector of the types for these
6446 non-type template parameters in PACKED_TYPES. */
6448 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6449 packed_types = tsubst_pack_expansion (expansion, args,
6452 if (packed_types == error_mark_node)
6453 return error_mark_node;
6455 /* Check that we have the right number of arguments. */
6457 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6458 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6461 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6462 error ("wrong number of template arguments (%d, should be %d)",
6463 nargs, needed_parms);
6464 return error_mark_node;
6467 /* If we aren't able to check the actual arguments now
6468 (because they haven't been expanded yet), we can at least
6469 verify that all of the types used for the non-type
6470 template parameter pack are, in fact, valid for non-type
6471 template parameters. */
6473 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6475 int j, len = TREE_VEC_LENGTH (packed_types);
6476 for (j = 0; j < len; ++j)
6478 tree t = TREE_VEC_ELT (packed_types, j);
6479 if (invalid_nontype_parm_type_p (t, complain))
6480 return error_mark_node;
6485 /* Convert the remaining arguments, which will be a part of the
6486 parameter pack "parm". */
6487 for (; arg_idx < nargs; ++arg_idx)
6489 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6490 tree actual_parm = TREE_VALUE (parm);
6492 if (packed_types && !PACK_EXPANSION_P (arg))
6494 /* When we have a vector of types (corresponding to the
6495 non-type template parameter pack that uses parameter
6496 packs in its type, as mention above), and the
6497 argument is not an expansion (which expands to a
6498 currently unknown number of arguments), clone the
6499 parm and give it the next type in PACKED_TYPES. */
6500 actual_parm = copy_node (actual_parm);
6501 TREE_TYPE (actual_parm) =
6502 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6505 if (arg != error_mark_node)
6506 arg = convert_template_argument (actual_parm,
6507 arg, new_args, complain, parm_idx,
6509 if (arg == error_mark_node)
6511 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6514 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6515 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6516 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6519 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6520 TREE_TYPE (argument_pack)
6521 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6522 TREE_CONSTANT (argument_pack) = 1;
6525 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6526 #ifdef ENABLE_CHECKING
6527 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6528 TREE_VEC_LENGTH (packed_args));
6530 return argument_pack;
6533 /* Convert all template arguments to their appropriate types, and
6534 return a vector containing the innermost resulting template
6535 arguments. If any error occurs, return error_mark_node. Error and
6536 warning messages are issued under control of COMPLAIN.
6538 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6539 for arguments not specified in ARGS. Otherwise, if
6540 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6541 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6542 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6546 coerce_template_parms (tree parms,
6549 tsubst_flags_t complain,
6550 bool require_all_args,
6551 bool use_default_args)
6553 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6556 tree new_inner_args;
6557 int saved_unevaluated_operand;
6558 int saved_inhibit_evaluation_warnings;
6560 /* When used as a boolean value, indicates whether this is a
6561 variadic template parameter list. Since it's an int, we can also
6562 subtract it from nparms to get the number of non-variadic
6565 int post_variadic_parms = 0;
6567 if (args == error_mark_node)
6568 return error_mark_node;
6570 nparms = TREE_VEC_LENGTH (parms);
6572 /* Determine if there are any parameter packs. */
6573 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6575 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6577 ++post_variadic_parms;
6578 if (template_parameter_pack_p (tparm))
6582 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6583 /* If there are no parameters that follow a parameter pack, we need to
6584 expand any argument packs so that we can deduce a parameter pack from
6585 some non-packed args followed by an argument pack, as in variadic85.C.
6586 If there are such parameters, we need to leave argument packs intact
6587 so the arguments are assigned properly. This can happen when dealing
6588 with a nested class inside a partial specialization of a class
6589 template, as in variadic92.C, or when deducing a template parameter pack
6590 from a sub-declarator, as in variadic114.C. */
6591 if (!post_variadic_parms)
6592 inner_args = expand_template_argument_pack (inner_args);
6594 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6595 if ((nargs > nparms && !variadic_p)
6596 || (nargs < nparms - variadic_p
6598 && (!use_default_args
6599 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6600 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6602 if (complain & tf_error)
6606 nparms -= variadic_p;
6607 error ("wrong number of template arguments "
6608 "(%d, should be %d or more)", nargs, nparms);
6611 error ("wrong number of template arguments "
6612 "(%d, should be %d)", nargs, nparms);
6615 error ("provided for %q+D", in_decl);
6618 return error_mark_node;
6621 /* We need to evaluate the template arguments, even though this
6622 template-id may be nested within a "sizeof". */
6623 saved_unevaluated_operand = cp_unevaluated_operand;
6624 cp_unevaluated_operand = 0;
6625 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6626 c_inhibit_evaluation_warnings = 0;
6627 new_inner_args = make_tree_vec (nparms);
6628 new_args = add_outermost_template_args (args, new_inner_args);
6629 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6634 /* Get the Ith template parameter. */
6635 parm = TREE_VEC_ELT (parms, parm_idx);
6637 if (parm == error_mark_node)
6639 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6643 /* Calculate the next argument. */
6644 if (arg_idx < nargs)
6645 arg = TREE_VEC_ELT (inner_args, arg_idx);
6649 if (template_parameter_pack_p (TREE_VALUE (parm))
6650 && !(arg && ARGUMENT_PACK_P (arg)))
6652 /* All remaining arguments will be placed in the
6653 template parameter pack PARM. */
6654 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6655 inner_args, arg_idx,
6659 /* Store this argument. */
6660 if (arg == error_mark_node)
6662 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6664 /* We are done with all of the arguments. */
6671 if (PACK_EXPANSION_P (arg))
6673 if (complain & tf_error)
6675 /* FIXME this restriction was removed by N2555; see
6677 /* If ARG is a pack expansion, but PARM is not a
6678 template parameter pack (if it were, we would have
6679 handled it above), we're trying to expand into a
6680 fixed-length argument list. */
6681 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
6682 sorry ("cannot expand %<%E%> into a fixed-length "
6683 "argument list", arg);
6685 sorry ("cannot expand %<%T%> into a fixed-length "
6686 "argument list", arg);
6691 else if (require_all_args)
6693 /* There must be a default arg in this case. */
6694 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6696 /* The position of the first default template argument,
6697 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6699 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6700 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6705 if (arg == error_mark_node)
6707 if (complain & tf_error)
6708 error ("template argument %d is invalid", arg_idx + 1);
6711 /* This only occurs if there was an error in the template
6712 parameter list itself (which we would already have
6713 reported) that we are trying to recover from, e.g., a class
6714 template with a parameter list such as
6715 template<typename..., typename>. */
6718 arg = convert_template_argument (TREE_VALUE (parm),
6719 arg, new_args, complain,
6722 if (arg == error_mark_node)
6724 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6726 cp_unevaluated_operand = saved_unevaluated_operand;
6727 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6730 return error_mark_node;
6732 #ifdef ENABLE_CHECKING
6733 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6734 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6735 TREE_VEC_LENGTH (new_inner_args));
6738 return new_inner_args;
6741 /* Returns 1 if template args OT and NT are equivalent. */
6744 template_args_equal (tree ot, tree nt)
6748 if (nt == NULL_TREE || ot == NULL_TREE)
6751 if (TREE_CODE (nt) == TREE_VEC)
6752 /* For member templates */
6753 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6754 else if (PACK_EXPANSION_P (ot))
6755 return PACK_EXPANSION_P (nt)
6756 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6757 PACK_EXPANSION_PATTERN (nt));
6758 else if (ARGUMENT_PACK_P (ot))
6763 if (!ARGUMENT_PACK_P (nt))
6766 opack = ARGUMENT_PACK_ARGS (ot);
6767 npack = ARGUMENT_PACK_ARGS (nt);
6768 len = TREE_VEC_LENGTH (opack);
6769 if (TREE_VEC_LENGTH (npack) != len)
6771 for (i = 0; i < len; ++i)
6772 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6773 TREE_VEC_ELT (npack, i)))
6777 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6779 /* We get here probably because we are in the middle of substituting
6780 into the pattern of a pack expansion. In that case the
6781 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6782 interested in. So we want to use the initial pack argument for
6784 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6785 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6786 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6787 return template_args_equal (ot, nt);
6789 else if (TYPE_P (nt))
6790 return TYPE_P (ot) && same_type_p (ot, nt);
6791 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6794 return cp_tree_equal (ot, nt);
6797 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6798 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6799 NEWARG_PTR with the offending arguments if they are non-NULL. */
6802 comp_template_args_with_info (tree oldargs, tree newargs,
6803 tree *oldarg_ptr, tree *newarg_ptr)
6807 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6810 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6812 tree nt = TREE_VEC_ELT (newargs, i);
6813 tree ot = TREE_VEC_ELT (oldargs, i);
6815 if (! template_args_equal (ot, nt))
6817 if (oldarg_ptr != NULL)
6819 if (newarg_ptr != NULL)
6827 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6828 of template arguments. Returns 0 otherwise. */
6831 comp_template_args (tree oldargs, tree newargs)
6833 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
6837 add_pending_template (tree d)
6839 tree ti = (TYPE_P (d)
6840 ? CLASSTYPE_TEMPLATE_INFO (d)
6841 : DECL_TEMPLATE_INFO (d));
6842 struct pending_template *pt;
6845 if (TI_PENDING_TEMPLATE_FLAG (ti))
6848 /* We are called both from instantiate_decl, where we've already had a
6849 tinst_level pushed, and instantiate_template, where we haven't.
6851 level = !current_tinst_level || current_tinst_level->decl != d;
6854 push_tinst_level (d);
6856 pt = ggc_alloc_pending_template ();
6858 pt->tinst = current_tinst_level;
6859 if (last_pending_template)
6860 last_pending_template->next = pt;
6862 pending_templates = pt;
6864 last_pending_template = pt;
6866 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6873 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6874 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6875 documentation for TEMPLATE_ID_EXPR. */
6878 lookup_template_function (tree fns, tree arglist)
6882 if (fns == error_mark_node || arglist == error_mark_node)
6883 return error_mark_node;
6885 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6887 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
6889 error ("%q#D is not a function template", fns);
6890 return error_mark_node;
6893 if (BASELINK_P (fns))
6895 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6897 BASELINK_FUNCTIONS (fns),
6902 type = TREE_TYPE (fns);
6903 if (TREE_CODE (fns) == OVERLOAD || !type)
6904 type = unknown_type_node;
6906 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6909 /* Within the scope of a template class S<T>, the name S gets bound
6910 (in build_self_reference) to a TYPE_DECL for the class, not a
6911 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6912 or one of its enclosing classes, and that type is a template,
6913 return the associated TEMPLATE_DECL. Otherwise, the original
6916 Also handle the case when DECL is a TREE_LIST of ambiguous
6917 injected-class-names from different bases. */
6920 maybe_get_template_decl_from_type_decl (tree decl)
6922 if (decl == NULL_TREE)
6925 /* DR 176: A lookup that finds an injected-class-name (10.2
6926 [class.member.lookup]) can result in an ambiguity in certain cases
6927 (for example, if it is found in more than one base class). If all of
6928 the injected-class-names that are found refer to specializations of
6929 the same class template, and if the name is followed by a
6930 template-argument-list, the reference refers to the class template
6931 itself and not a specialization thereof, and is not ambiguous. */
6932 if (TREE_CODE (decl) == TREE_LIST)
6934 tree t, tmpl = NULL_TREE;
6935 for (t = decl; t; t = TREE_CHAIN (t))
6937 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6940 else if (tmpl != elt)
6943 if (tmpl && t == NULL_TREE)
6949 return (decl != NULL_TREE
6950 && DECL_SELF_REFERENCE_P (decl)
6951 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6952 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6955 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6956 parameters, find the desired type.
6958 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6960 IN_DECL, if non-NULL, is the template declaration we are trying to
6963 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6964 the class we are looking up.
6966 Issue error and warning messages under control of COMPLAIN.
6968 If the template class is really a local class in a template
6969 function, then the FUNCTION_CONTEXT is the function in which it is
6972 ??? Note that this function is currently called *twice* for each
6973 template-id: the first time from the parser, while creating the
6974 incomplete type (finish_template_type), and the second type during the
6975 real instantiation (instantiate_template_class). This is surely something
6976 that we want to avoid. It also causes some problems with argument
6977 coercion (see convert_nontype_argument for more information on this). */
6980 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
6981 int entering_scope, tsubst_flags_t complain)
6983 tree templ = NULL_TREE, parmlist;
6990 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6992 tree value = innermost_non_namespace_value (d1);
6993 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6998 push_decl_namespace (context);
6999 templ = lookup_name (d1);
7000 templ = maybe_get_template_decl_from_type_decl (templ);
7002 pop_decl_namespace ();
7005 context = DECL_CONTEXT (templ);
7007 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7009 tree type = TREE_TYPE (d1);
7011 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7012 an implicit typename for the second A. Deal with it. */
7013 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7014 type = TREE_TYPE (type);
7016 if (CLASSTYPE_TEMPLATE_INFO (type))
7018 templ = CLASSTYPE_TI_TEMPLATE (type);
7019 d1 = DECL_NAME (templ);
7022 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7023 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7025 templ = TYPE_TI_TEMPLATE (d1);
7026 d1 = DECL_NAME (templ);
7028 else if (TREE_CODE (d1) == TEMPLATE_DECL
7029 && DECL_TEMPLATE_RESULT (d1)
7030 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7033 d1 = DECL_NAME (templ);
7034 context = DECL_CONTEXT (templ);
7037 /* Issue an error message if we didn't find a template. */
7040 if (complain & tf_error)
7041 error ("%qT is not a template", d1);
7042 return error_mark_node;
7045 if (TREE_CODE (templ) != TEMPLATE_DECL
7046 /* Make sure it's a user visible template, if it was named by
7048 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7049 && !PRIMARY_TEMPLATE_P (templ)))
7051 if (complain & tf_error)
7053 error ("non-template type %qT used as a template", d1);
7055 error ("for template declaration %q+D", in_decl);
7057 return error_mark_node;
7060 complain &= ~tf_user;
7062 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7064 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7065 template arguments */
7071 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7073 /* Consider an example where a template template parameter declared as
7075 template <class T, class U = std::allocator<T> > class TT
7077 The template parameter level of T and U are one level larger than
7078 of TT. To proper process the default argument of U, say when an
7079 instantiation `TT<int>' is seen, we need to build the full
7080 arguments containing {int} as the innermost level. Outer levels,
7081 available when not appearing as default template argument, can be
7082 obtained from the arguments of the enclosing template.
7084 Suppose that TT is later substituted with std::vector. The above
7085 instantiation is `TT<int, std::allocator<T> >' with TT at
7086 level 1, and T at level 2, while the template arguments at level 1
7087 becomes {std::vector} and the inner level 2 is {int}. */
7089 outer = DECL_CONTEXT (templ);
7091 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7092 else if (current_template_parms)
7093 /* This is an argument of the current template, so we haven't set
7094 DECL_CONTEXT yet. */
7095 outer = current_template_args ();
7098 arglist = add_to_template_args (outer, arglist);
7100 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7102 /*require_all_args=*/true,
7103 /*use_default_args=*/true);
7104 if (arglist2 == error_mark_node
7105 || (!uses_template_parms (arglist2)
7106 && check_instantiated_args (templ, arglist2, complain)))
7107 return error_mark_node;
7109 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7114 tree template_type = TREE_TYPE (templ);
7117 tree found = NULL_TREE;
7120 int is_dependent_type;
7121 int use_partial_inst_tmpl = false;
7123 gen_tmpl = most_general_template (templ);
7124 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7125 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7126 arg_depth = TMPL_ARGS_DEPTH (arglist);
7128 if (arg_depth == 1 && parm_depth > 1)
7130 /* We've been given an incomplete set of template arguments.
7133 template <class T> struct S1 {
7134 template <class U> struct S2 {};
7135 template <class U> struct S2<U*> {};
7138 we will be called with an ARGLIST of `U*', but the
7139 TEMPLATE will be `template <class T> template
7140 <class U> struct S1<T>::S2'. We must fill in the missing
7143 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7145 arg_depth = TMPL_ARGS_DEPTH (arglist);
7148 /* Now we should have enough arguments. */
7149 gcc_assert (parm_depth == arg_depth);
7151 /* From here on, we're only interested in the most general
7154 /* Calculate the BOUND_ARGS. These will be the args that are
7155 actually tsubst'd into the definition to create the
7159 /* We have multiple levels of arguments to coerce, at once. */
7161 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7163 tree bound_args = make_tree_vec (parm_depth);
7165 for (i = saved_depth,
7166 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7167 i > 0 && t != NULL_TREE;
7168 --i, t = TREE_CHAIN (t))
7171 if (i == saved_depth)
7172 a = coerce_template_parms (TREE_VALUE (t),
7175 /*require_all_args=*/true,
7176 /*use_default_args=*/true);
7178 /* Outer levels should have already been coerced. */
7179 a = TMPL_ARGS_LEVEL (arglist, i);
7181 /* Don't process further if one of the levels fails. */
7182 if (a == error_mark_node)
7184 /* Restore the ARGLIST to its full size. */
7185 TREE_VEC_LENGTH (arglist) = saved_depth;
7186 return error_mark_node;
7189 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7191 /* We temporarily reduce the length of the ARGLIST so
7192 that coerce_template_parms will see only the arguments
7193 corresponding to the template parameters it is
7195 TREE_VEC_LENGTH (arglist)--;
7198 /* Restore the ARGLIST to its full size. */
7199 TREE_VEC_LENGTH (arglist) = saved_depth;
7201 arglist = bound_args;
7205 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7206 INNERMOST_TEMPLATE_ARGS (arglist),
7209 /*require_all_args=*/true,
7210 /*use_default_args=*/true);
7212 if (arglist == error_mark_node)
7213 /* We were unable to bind the arguments. */
7214 return error_mark_node;
7216 /* In the scope of a template class, explicit references to the
7217 template class refer to the type of the template, not any
7218 instantiation of it. For example, in:
7220 template <class T> class C { void f(C<T>); }
7222 the `C<T>' is just the same as `C'. Outside of the
7223 class, however, such a reference is an instantiation. */
7225 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7226 || currently_open_class (template_type))
7227 /* comp_template_args is expensive, check it last. */
7228 && comp_template_args (TYPE_TI_ARGS (template_type),
7230 return template_type;
7232 /* If we already have this specialization, return it. */
7233 elt.tmpl = gen_tmpl;
7235 hash = hash_specialization (&elt);
7236 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7242 is_dependent_type = uses_template_parms (arglist);
7244 /* If the deduced arguments are invalid, then the binding
7246 if (!is_dependent_type
7247 && check_instantiated_args (gen_tmpl,
7248 INNERMOST_TEMPLATE_ARGS (arglist),
7250 return error_mark_node;
7252 if (!is_dependent_type
7253 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7254 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7255 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7257 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7258 DECL_NAME (gen_tmpl),
7259 /*tag_scope=*/ts_global);
7263 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7266 context = global_namespace;
7268 /* Create the type. */
7269 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7271 if (!is_dependent_type)
7273 set_current_access_from_decl (TYPE_NAME (template_type));
7274 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7275 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7276 arglist, complain, in_decl),
7277 SCOPED_ENUM_P (template_type), NULL);
7281 /* We don't want to call start_enum for this type, since
7282 the values for the enumeration constants may involve
7283 template parameters. And, no one should be interested
7284 in the enumeration constants for such a type. */
7285 t = cxx_make_type (ENUMERAL_TYPE);
7286 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7288 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7289 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7290 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7294 t = make_class_type (TREE_CODE (template_type));
7295 CLASSTYPE_DECLARED_CLASS (t)
7296 = CLASSTYPE_DECLARED_CLASS (template_type);
7297 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7298 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7300 /* A local class. Make sure the decl gets registered properly. */
7301 if (context == current_function_decl)
7302 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7304 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7305 /* This instantiation is another name for the primary
7306 template type. Set the TYPE_CANONICAL field
7308 TYPE_CANONICAL (t) = template_type;
7309 else if (any_template_arguments_need_structural_equality_p (arglist))
7310 /* Some of the template arguments require structural
7311 equality testing, so this template class requires
7312 structural equality testing. */
7313 SET_TYPE_STRUCTURAL_EQUALITY (t);
7316 /* If we called start_enum or pushtag above, this information
7317 will already be set up. */
7320 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7322 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7323 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7324 DECL_SOURCE_LOCATION (type_decl)
7325 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7328 type_decl = TYPE_NAME (t);
7330 TREE_PRIVATE (type_decl)
7331 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7332 TREE_PROTECTED (type_decl)
7333 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7334 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7336 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7337 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7340 /* Let's consider the explicit specialization of a member
7341 of a class template specialization that is implicitely instantiated,
7346 template<class U> struct M {}; //#0
7351 struct S<int>::M<char> //#1
7355 [temp.expl.spec]/4 says this is valid.
7357 In this case, when we write:
7360 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7363 When we encounter #1, we want to store the partial instantiation
7364 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7366 For all cases other than this "explicit specialization of member of a
7367 class template", we just want to store the most general template into
7368 the CLASSTYPE_TI_TEMPLATE of M.
7370 This case of "explicit specialization of member of a class template"
7372 1/ the enclosing class is an instantiation of, and therefore not
7373 the same as, the context of the most general template, and
7374 2/ we aren't looking at the partial instantiation itself, i.e.
7375 the innermost arguments are not the same as the innermost parms of
7376 the most general template.
7378 So it's only when 1/ and 2/ happens that we want to use the partial
7379 instantiation of the member template in lieu of its most general
7382 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7383 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7384 /* the enclosing class must be an instantiation... */
7385 && CLASS_TYPE_P (context)
7386 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7388 tree partial_inst_args;
7389 TREE_VEC_LENGTH (arglist)--;
7390 ++processing_template_decl;
7392 tsubst (INNERMOST_TEMPLATE_ARGS
7393 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7394 arglist, complain, NULL_TREE);
7395 --processing_template_decl;
7396 TREE_VEC_LENGTH (arglist)++;
7397 use_partial_inst_tmpl =
7398 /*...and we must not be looking at the partial instantiation
7400 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7404 if (!use_partial_inst_tmpl)
7405 /* This case is easy; there are no member templates involved. */
7409 /* This is a full instantiation of a member template. Find
7410 the partial instantiation of which this is an instance. */
7412 /* Temporarily reduce by one the number of levels in the ARGLIST
7413 so as to avoid comparing the last set of arguments. */
7414 TREE_VEC_LENGTH (arglist)--;
7415 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7416 TREE_VEC_LENGTH (arglist)++;
7417 found = CLASSTYPE_TI_TEMPLATE (found);
7420 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7423 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
7424 &elt, hash, INSERT);
7425 *slot = ggc_alloc_spec_entry ();
7428 /* Note this use of the partial instantiation so we can check it
7429 later in maybe_process_partial_specialization. */
7430 DECL_TEMPLATE_INSTANTIATIONS (templ)
7431 = tree_cons (arglist, t,
7432 DECL_TEMPLATE_INSTANTIATIONS (templ));
7434 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7435 /* Now that the type has been registered on the instantiations
7436 list, we set up the enumerators. Because the enumeration
7437 constants may involve the enumeration type itself, we make
7438 sure to register the type first, and then create the
7439 constants. That way, doing tsubst_expr for the enumeration
7440 constants won't result in recursive calls here; we'll find
7441 the instantiation and exit above. */
7442 tsubst_enum (template_type, t, arglist);
7444 if (is_dependent_type)
7445 /* If the type makes use of template parameters, the
7446 code that generates debugging information will crash. */
7447 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7449 /* Possibly limit visibility based on template args. */
7450 TREE_PUBLIC (type_decl) = 1;
7451 determine_visibility (type_decl);
7457 /* Wrapper for lookup_template_class_1. */
7460 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7461 int entering_scope, tsubst_flags_t complain)
7464 timevar_push (TV_TEMPLATE_INST);
7465 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7466 entering_scope, complain);
7467 timevar_pop (TV_TEMPLATE_INST);
7475 /* True when we should also visit template parameters that occur in
7476 non-deduced contexts. */
7477 bool include_nondeduced_p;
7478 struct pointer_set_t *visited;
7481 /* Called from for_each_template_parm via walk_tree. */
7484 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7487 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7488 tree_fn_t fn = pfd->fn;
7489 void *data = pfd->data;
7492 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7493 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7494 pfd->include_nondeduced_p))
7495 return error_mark_node;
7497 switch (TREE_CODE (t))
7500 if (TYPE_PTRMEMFUNC_P (t))
7506 if (!TYPE_TEMPLATE_INFO (t))
7508 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7509 fn, data, pfd->visited,
7510 pfd->include_nondeduced_p))
7511 return error_mark_node;
7515 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7516 fn, data, pfd->visited,
7517 pfd->include_nondeduced_p)
7518 || for_each_template_parm (TYPE_MAX_VALUE (t),
7519 fn, data, pfd->visited,
7520 pfd->include_nondeduced_p))
7521 return error_mark_node;
7525 /* Since we're not going to walk subtrees, we have to do this
7527 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7528 pfd->visited, pfd->include_nondeduced_p))
7529 return error_mark_node;
7533 /* Check the return type. */
7534 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7535 pfd->include_nondeduced_p))
7536 return error_mark_node;
7538 /* Check the parameter types. Since default arguments are not
7539 instantiated until they are needed, the TYPE_ARG_TYPES may
7540 contain expressions that involve template parameters. But,
7541 no-one should be looking at them yet. And, once they're
7542 instantiated, they don't contain template parameters, so
7543 there's no point in looking at them then, either. */
7547 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7548 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7549 pfd->visited, pfd->include_nondeduced_p))
7550 return error_mark_node;
7552 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7553 want walk_tree walking into them itself. */
7559 case UNDERLYING_TYPE:
7560 if (pfd->include_nondeduced_p
7561 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7563 pfd->include_nondeduced_p))
7564 return error_mark_node;
7569 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7570 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7571 pfd->visited, pfd->include_nondeduced_p))
7572 return error_mark_node;
7577 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7578 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7579 pfd->visited, pfd->include_nondeduced_p))
7580 return error_mark_node;
7581 if (DECL_CONTEXT (t)
7582 && pfd->include_nondeduced_p
7583 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7584 pfd->visited, pfd->include_nondeduced_p))
7585 return error_mark_node;
7588 case BOUND_TEMPLATE_TEMPLATE_PARM:
7589 /* Record template parameters such as `T' inside `TT<T>'. */
7590 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7591 pfd->include_nondeduced_p))
7592 return error_mark_node;
7595 case TEMPLATE_TEMPLATE_PARM:
7596 case TEMPLATE_TYPE_PARM:
7597 case TEMPLATE_PARM_INDEX:
7598 if (fn && (*fn)(t, data))
7599 return error_mark_node;
7601 return error_mark_node;
7605 /* A template template parameter is encountered. */
7606 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7607 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7608 pfd->include_nondeduced_p))
7609 return error_mark_node;
7611 /* Already substituted template template parameter */
7617 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7619 pfd->include_nondeduced_p))
7620 return error_mark_node;
7624 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7625 && pfd->include_nondeduced_p
7626 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7627 (TREE_TYPE (t)), fn, data,
7628 pfd->visited, pfd->include_nondeduced_p))
7629 return error_mark_node;
7634 /* If there's no type, then this thing must be some expression
7635 involving template parameters. */
7636 if (!fn && !TREE_TYPE (t))
7637 return error_mark_node;
7642 case REINTERPRET_CAST_EXPR:
7643 case CONST_CAST_EXPR:
7644 case STATIC_CAST_EXPR:
7645 case DYNAMIC_CAST_EXPR:
7649 case PSEUDO_DTOR_EXPR:
7651 return error_mark_node;
7658 /* We didn't find any template parameters we liked. */
7662 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7663 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7664 call FN with the parameter and the DATA.
7665 If FN returns nonzero, the iteration is terminated, and
7666 for_each_template_parm returns 1. Otherwise, the iteration
7667 continues. If FN never returns a nonzero value, the value
7668 returned by for_each_template_parm is 0. If FN is NULL, it is
7669 considered to be the function which always returns 1.
7671 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7672 parameters that occur in non-deduced contexts. When false, only
7673 visits those template parameters that can be deduced. */
7676 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7677 struct pointer_set_t *visited,
7678 bool include_nondeduced_p)
7680 struct pair_fn_data pfd;
7686 pfd.include_nondeduced_p = include_nondeduced_p;
7688 /* Walk the tree. (Conceptually, we would like to walk without
7689 duplicates, but for_each_template_parm_r recursively calls
7690 for_each_template_parm, so we would need to reorganize a fair
7691 bit to use walk_tree_without_duplicates, so we keep our own
7694 pfd.visited = visited;
7696 pfd.visited = pointer_set_create ();
7697 result = cp_walk_tree (&t,
7698 for_each_template_parm_r,
7700 pfd.visited) != NULL_TREE;
7705 pointer_set_destroy (pfd.visited);
7712 /* Returns true if T depends on any template parameter. */
7715 uses_template_parms (tree t)
7718 int saved_processing_template_decl;
7720 saved_processing_template_decl = processing_template_decl;
7721 if (!saved_processing_template_decl)
7722 processing_template_decl = 1;
7724 dependent_p = dependent_type_p (t);
7725 else if (TREE_CODE (t) == TREE_VEC)
7726 dependent_p = any_dependent_template_arguments_p (t);
7727 else if (TREE_CODE (t) == TREE_LIST)
7728 dependent_p = (uses_template_parms (TREE_VALUE (t))
7729 || uses_template_parms (TREE_CHAIN (t)));
7730 else if (TREE_CODE (t) == TYPE_DECL)
7731 dependent_p = dependent_type_p (TREE_TYPE (t));
7734 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7735 || TREE_CODE (t) == OVERLOAD
7736 || TREE_CODE (t) == BASELINK
7737 || TREE_CODE (t) == IDENTIFIER_NODE
7738 || TREE_CODE (t) == TRAIT_EXPR
7739 || TREE_CODE (t) == CONSTRUCTOR
7740 || CONSTANT_CLASS_P (t))
7741 dependent_p = (type_dependent_expression_p (t)
7742 || value_dependent_expression_p (t));
7745 gcc_assert (t == error_mark_node);
7746 dependent_p = false;
7749 processing_template_decl = saved_processing_template_decl;
7754 /* Returns true if T depends on any template parameter with level LEVEL. */
7757 uses_template_parms_level (tree t, int level)
7759 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7760 /*include_nondeduced_p=*/true);
7763 /* Returns TRUE iff INST is an instantiation we don't need to do in an
7764 ill-formed translation unit, i.e. a variable or function that isn't
7765 usable in a constant expression. */
7768 neglectable_inst_p (tree d)
7771 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
7772 : decl_maybe_constant_var_p (d)));
7775 /* Returns TRUE iff we should refuse to instantiate DECL because it's
7776 neglectable and instantiated from within an erroneous instantiation. */
7779 limit_bad_template_recursion (tree decl)
7781 struct tinst_level *lev = current_tinst_level;
7782 int errs = errorcount + sorrycount;
7783 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
7786 for (; lev; lev = lev->next)
7787 if (neglectable_inst_p (lev->decl))
7790 return (lev && errs > lev->errors);
7793 static int tinst_depth;
7794 extern int max_tinst_depth;
7795 #ifdef GATHER_STATISTICS
7798 static GTY(()) struct tinst_level *last_error_tinst_level;
7800 /* We're starting to instantiate D; record the template instantiation context
7801 for diagnostics and to restore it later. */
7804 push_tinst_level (tree d)
7806 struct tinst_level *new_level;
7808 if (tinst_depth >= max_tinst_depth)
7810 last_error_tinst_level = current_tinst_level;
7811 if (TREE_CODE (d) == TREE_LIST)
7812 error ("template instantiation depth exceeds maximum of %d (use "
7813 "-ftemplate-depth= to increase the maximum) substituting %qS",
7814 max_tinst_depth, d);
7816 error ("template instantiation depth exceeds maximum of %d (use "
7817 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7818 max_tinst_depth, d);
7820 print_instantiation_context ();
7825 /* If the current instantiation caused problems, don't let it instantiate
7826 anything else. Do allow deduction substitution and decls usable in
7827 constant expressions. */
7828 if (limit_bad_template_recursion (d))
7831 new_level = ggc_alloc_tinst_level ();
7832 new_level->decl = d;
7833 new_level->locus = input_location;
7834 new_level->errors = errorcount+sorrycount;
7835 new_level->in_system_header_p = in_system_header;
7836 new_level->next = current_tinst_level;
7837 current_tinst_level = new_level;
7840 #ifdef GATHER_STATISTICS
7841 if (tinst_depth > depth_reached)
7842 depth_reached = tinst_depth;
7848 /* We're done instantiating this template; return to the instantiation
7852 pop_tinst_level (void)
7854 /* Restore the filename and line number stashed away when we started
7855 this instantiation. */
7856 input_location = current_tinst_level->locus;
7857 current_tinst_level = current_tinst_level->next;
7861 /* We're instantiating a deferred template; restore the template
7862 instantiation context in which the instantiation was requested, which
7863 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7866 reopen_tinst_level (struct tinst_level *level)
7868 struct tinst_level *t;
7871 for (t = level; t; t = t->next)
7874 current_tinst_level = level;
7876 if (current_tinst_level)
7877 current_tinst_level->errors = errorcount+sorrycount;
7881 /* Returns the TINST_LEVEL which gives the original instantiation
7884 struct tinst_level *
7885 outermost_tinst_level (void)
7887 struct tinst_level *level = current_tinst_level;
7890 level = level->next;
7894 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7897 parameter_of_template_p (tree parm, tree templ)
7902 if (!parm || !templ)
7905 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7906 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7908 parms = DECL_TEMPLATE_PARMS (templ);
7909 parms = INNERMOST_TEMPLATE_PARMS (parms);
7911 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7913 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
7915 || (DECL_INITIAL (parm)
7916 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
7923 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7924 vector of template arguments, as for tsubst.
7926 Returns an appropriate tsubst'd friend declaration. */
7929 tsubst_friend_function (tree decl, tree args)
7933 if (TREE_CODE (decl) == FUNCTION_DECL
7934 && DECL_TEMPLATE_INSTANTIATION (decl)
7935 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7936 /* This was a friend declared with an explicit template
7937 argument list, e.g.:
7941 to indicate that f was a template instantiation, not a new
7942 function declaration. Now, we have to figure out what
7943 instantiation of what template. */
7945 tree template_id, arglist, fns;
7948 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7950 /* Friend functions are looked up in the containing namespace scope.
7951 We must enter that scope, to avoid finding member functions of the
7952 current class with same name. */
7953 push_nested_namespace (ns);
7954 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7955 tf_warning_or_error, NULL_TREE,
7956 /*integral_constant_expression_p=*/false);
7957 pop_nested_namespace (ns);
7958 arglist = tsubst (DECL_TI_ARGS (decl), args,
7959 tf_warning_or_error, NULL_TREE);
7960 template_id = lookup_template_function (fns, arglist);
7962 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7963 tmpl = determine_specialization (template_id, new_friend,
7965 /*need_member_template=*/0,
7966 TREE_VEC_LENGTH (args),
7968 return instantiate_template (tmpl, new_args, tf_error);
7971 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7973 /* The NEW_FRIEND will look like an instantiation, to the
7974 compiler, but is not an instantiation from the point of view of
7975 the language. For example, we might have had:
7977 template <class T> struct S {
7978 template <class U> friend void f(T, U);
7981 Then, in S<int>, template <class U> void f(int, U) is not an
7982 instantiation of anything. */
7983 if (new_friend == error_mark_node)
7984 return error_mark_node;
7986 DECL_USE_TEMPLATE (new_friend) = 0;
7987 if (TREE_CODE (decl) == TEMPLATE_DECL)
7989 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7990 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7991 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7994 /* The mangled name for the NEW_FRIEND is incorrect. The function
7995 is not a template instantiation and should not be mangled like
7996 one. Therefore, we forget the mangling here; we'll recompute it
7997 later if we need it. */
7998 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8000 SET_DECL_RTL (new_friend, NULL);
8001 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8004 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8007 tree new_friend_template_info;
8008 tree new_friend_result_template_info;
8010 int new_friend_is_defn;
8012 /* We must save some information from NEW_FRIEND before calling
8013 duplicate decls since that function will free NEW_FRIEND if
8015 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8016 new_friend_is_defn =
8017 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8018 (template_for_substitution (new_friend)))
8020 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8022 /* This declaration is a `primary' template. */
8023 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8025 new_friend_result_template_info
8026 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8029 new_friend_result_template_info = NULL_TREE;
8031 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8032 if (new_friend_is_defn)
8033 DECL_INITIAL (new_friend) = error_mark_node;
8035 /* Inside pushdecl_namespace_level, we will push into the
8036 current namespace. However, the friend function should go
8037 into the namespace of the template. */
8038 ns = decl_namespace_context (new_friend);
8039 push_nested_namespace (ns);
8040 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8041 pop_nested_namespace (ns);
8043 if (old_decl == error_mark_node)
8044 return error_mark_node;
8046 if (old_decl != new_friend)
8048 /* This new friend declaration matched an existing
8049 declaration. For example, given:
8051 template <class T> void f(T);
8052 template <class U> class C {
8053 template <class T> friend void f(T) {}
8056 the friend declaration actually provides the definition
8057 of `f', once C has been instantiated for some type. So,
8058 old_decl will be the out-of-class template declaration,
8059 while new_friend is the in-class definition.
8061 But, if `f' was called before this point, the
8062 instantiation of `f' will have DECL_TI_ARGS corresponding
8063 to `T' but not to `U', references to which might appear
8064 in the definition of `f'. Previously, the most general
8065 template for an instantiation of `f' was the out-of-class
8066 version; now it is the in-class version. Therefore, we
8067 run through all specialization of `f', adding to their
8068 DECL_TI_ARGS appropriately. In particular, they need a
8069 new set of outer arguments, corresponding to the
8070 arguments for this class instantiation.
8072 The same situation can arise with something like this:
8075 template <class T> class C {
8079 when `C<int>' is instantiated. Now, `f(int)' is defined
8082 if (!new_friend_is_defn)
8083 /* On the other hand, if the in-class declaration does
8084 *not* provide a definition, then we don't want to alter
8085 existing definitions. We can just leave everything
8090 tree new_template = TI_TEMPLATE (new_friend_template_info);
8091 tree new_args = TI_ARGS (new_friend_template_info);
8093 /* Overwrite whatever template info was there before, if
8094 any, with the new template information pertaining to
8096 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8098 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8100 /* We should have called reregister_specialization in
8102 gcc_assert (retrieve_specialization (new_template,
8106 /* Instantiate it if the global has already been used. */
8107 if (DECL_ODR_USED (old_decl))
8108 instantiate_decl (old_decl, /*defer_ok=*/true,
8109 /*expl_inst_class_mem_p=*/false);
8115 /* Indicate that the old function template is a partial
8117 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8118 = new_friend_result_template_info;
8120 gcc_assert (new_template
8121 == most_general_template (new_template));
8122 gcc_assert (new_template != old_decl);
8124 /* Reassign any specializations already in the hash table
8125 to the new more general template, and add the
8126 additional template args. */
8127 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8131 tree spec = TREE_VALUE (t);
8134 elt.tmpl = old_decl;
8135 elt.args = DECL_TI_ARGS (spec);
8136 elt.spec = NULL_TREE;
8138 htab_remove_elt (decl_specializations, &elt);
8141 = add_outermost_template_args (new_args,
8142 DECL_TI_ARGS (spec));
8144 register_specialization
8145 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8148 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8152 /* The information from NEW_FRIEND has been merged into OLD_DECL
8153 by duplicate_decls. */
8154 new_friend = old_decl;
8159 tree context = DECL_CONTEXT (new_friend);
8163 template <class T> class C {
8164 template <class U> friend void C1<U>::f (); // case 1
8165 friend void C2<T>::f (); // case 2
8167 we only need to make sure CONTEXT is a complete type for
8168 case 2. To distinguish between the two cases, we note that
8169 CONTEXT of case 1 remains dependent type after tsubst while
8170 this isn't true for case 2. */
8171 ++processing_template_decl;
8172 dependent_p = dependent_type_p (context);
8173 --processing_template_decl;
8176 && !complete_type_or_else (context, NULL_TREE))
8177 return error_mark_node;
8179 if (COMPLETE_TYPE_P (context))
8181 /* Check to see that the declaration is really present, and,
8182 possibly obtain an improved declaration. */
8183 tree fn = check_classfn (context,
8184 new_friend, NULL_TREE);
8194 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8195 template arguments, as for tsubst.
8197 Returns an appropriate tsubst'd friend type or error_mark_node on
8201 tsubst_friend_class (tree friend_tmpl, tree args)
8207 context = CP_DECL_CONTEXT (friend_tmpl);
8209 if (context != global_namespace)
8211 if (TREE_CODE (context) == NAMESPACE_DECL)
8212 push_nested_namespace (context);
8214 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8217 /* Look for a class template declaration. We look for hidden names
8218 because two friend declarations of the same template are the
8219 same. For example, in:
8222 template <typename> friend class F;
8224 template <typename> struct B {
8225 template <typename> friend class F;
8228 both F templates are the same. */
8229 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8230 /*block_p=*/true, 0,
8231 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8233 /* But, if we don't find one, it might be because we're in a
8234 situation like this:
8242 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8243 for `S<int>', not the TEMPLATE_DECL. */
8244 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8246 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8247 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8250 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8252 /* The friend template has already been declared. Just
8253 check to see that the declarations match, and install any new
8254 default parameters. We must tsubst the default parameters,
8255 of course. We only need the innermost template parameters
8256 because that is all that redeclare_class_template will look
8258 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8259 > TMPL_ARGS_DEPTH (args))
8262 location_t saved_input_location;
8263 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8264 args, tf_warning_or_error);
8266 saved_input_location = input_location;
8267 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8268 redeclare_class_template (TREE_TYPE (tmpl), parms);
8269 input_location = saved_input_location;
8273 friend_type = TREE_TYPE (tmpl);
8277 /* The friend template has not already been declared. In this
8278 case, the instantiation of the template class will cause the
8279 injection of this template into the global scope. */
8280 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8281 if (tmpl == error_mark_node)
8282 return error_mark_node;
8284 /* The new TMPL is not an instantiation of anything, so we
8285 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8286 the new type because that is supposed to be the corresponding
8287 template decl, i.e., TMPL. */
8288 DECL_USE_TEMPLATE (tmpl) = 0;
8289 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8290 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8291 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8292 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8294 /* Inject this template into the global scope. */
8295 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8298 if (context != global_namespace)
8300 if (TREE_CODE (context) == NAMESPACE_DECL)
8301 pop_nested_namespace (context);
8303 pop_nested_class ();
8309 /* Returns zero if TYPE cannot be completed later due to circularity.
8310 Otherwise returns one. */
8313 can_complete_type_without_circularity (tree type)
8315 if (type == NULL_TREE || type == error_mark_node)
8317 else if (COMPLETE_TYPE_P (type))
8319 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8320 return can_complete_type_without_circularity (TREE_TYPE (type));
8321 else if (CLASS_TYPE_P (type)
8322 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8328 /* Apply any attributes which had to be deferred until instantiation
8329 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8330 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8333 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8334 tree args, tsubst_flags_t complain, tree in_decl)
8336 tree last_dep = NULL_TREE;
8340 for (t = attributes; t; t = TREE_CHAIN (t))
8341 if (ATTR_IS_DEPENDENT (t))
8344 attributes = copy_list (attributes);
8348 if (DECL_P (*decl_p))
8350 if (TREE_TYPE (*decl_p) == error_mark_node)
8352 p = &DECL_ATTRIBUTES (*decl_p);
8355 p = &TYPE_ATTRIBUTES (*decl_p);
8359 tree late_attrs = NULL_TREE;
8360 tree *q = &late_attrs;
8362 for (*p = attributes; *p; )
8365 if (ATTR_IS_DEPENDENT (t))
8367 *p = TREE_CHAIN (t);
8368 TREE_CHAIN (t) = NULL_TREE;
8369 /* If the first attribute argument is an identifier, don't
8370 pass it through tsubst. Attributes like mode, format,
8371 cleanup and several target specific attributes expect it
8374 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8375 && TREE_VALUE (TREE_VALUE (t))
8376 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8377 == IDENTIFIER_NODE))
8380 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8382 /*integral_constant_expression_p=*/false);
8383 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8385 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8390 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8391 /*integral_constant_expression_p=*/false);
8393 q = &TREE_CHAIN (t);
8396 p = &TREE_CHAIN (t);
8399 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8403 /* Perform (or defer) access check for typedefs that were referenced
8404 from within the template TMPL code.
8405 This is a subroutine of instantiate_template and instantiate_class_template.
8406 TMPL is the template to consider and TARGS is the list of arguments of
8410 perform_typedefs_access_check (tree tmpl, tree targs)
8412 location_t saved_location;
8414 qualified_typedef_usage_t *iter;
8417 || (!CLASS_TYPE_P (tmpl)
8418 && TREE_CODE (tmpl) != FUNCTION_DECL))
8421 saved_location = input_location;
8422 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8423 get_types_needing_access_check (tmpl),
8426 tree type_decl = iter->typedef_decl;
8427 tree type_scope = iter->context;
8429 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8432 if (uses_template_parms (type_decl))
8433 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8434 if (uses_template_parms (type_scope))
8435 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8437 /* Make access check error messages point to the location
8438 of the use of the typedef. */
8439 input_location = iter->locus;
8440 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8441 type_decl, type_decl);
8443 input_location = saved_location;
8447 instantiate_class_template_1 (tree type)
8449 tree templ, args, pattern, t, member;
8453 unsigned int saved_maximum_field_alignment;
8455 if (type == error_mark_node)
8456 return error_mark_node;
8458 if (COMPLETE_OR_OPEN_TYPE_P (type)
8459 || uses_template_parms (type))
8462 /* Figure out which template is being instantiated. */
8463 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8464 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8466 /* Determine what specialization of the original template to
8468 t = most_specialized_class (type, templ, tf_warning_or_error);
8469 if (t == error_mark_node)
8471 TYPE_BEING_DEFINED (type) = 1;
8472 return error_mark_node;
8476 /* This TYPE is actually an instantiation of a partial
8477 specialization. We replace the innermost set of ARGS with
8478 the arguments appropriate for substitution. For example,
8481 template <class T> struct S {};
8482 template <class T> struct S<T*> {};
8484 and supposing that we are instantiating S<int*>, ARGS will
8485 presently be {int*} -- but we need {int}. */
8486 pattern = TREE_TYPE (t);
8487 args = TREE_PURPOSE (t);
8491 pattern = TREE_TYPE (templ);
8492 args = CLASSTYPE_TI_ARGS (type);
8495 /* If the template we're instantiating is incomplete, then clearly
8496 there's nothing we can do. */
8497 if (!COMPLETE_TYPE_P (pattern))
8500 /* If we've recursively instantiated too many templates, stop. */
8501 if (! push_tinst_level (type))
8504 /* Now we're really doing the instantiation. Mark the type as in
8505 the process of being defined. */
8506 TYPE_BEING_DEFINED (type) = 1;
8508 /* We may be in the middle of deferred access check. Disable
8510 push_deferring_access_checks (dk_no_deferred);
8512 push_to_top_level ();
8513 /* Use #pragma pack from the template context. */
8514 saved_maximum_field_alignment = maximum_field_alignment;
8515 maximum_field_alignment = TYPE_PRECISION (pattern);
8517 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8519 /* Set the input location to the most specialized template definition.
8520 This is needed if tsubsting causes an error. */
8521 typedecl = TYPE_MAIN_DECL (pattern);
8522 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8523 DECL_SOURCE_LOCATION (typedecl);
8525 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8526 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8527 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8528 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8529 if (ANON_AGGR_TYPE_P (pattern))
8530 SET_ANON_AGGR_TYPE_P (type);
8531 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8533 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8534 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8536 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8538 pbinfo = TYPE_BINFO (pattern);
8540 /* We should never instantiate a nested class before its enclosing
8541 class; we need to look up the nested class by name before we can
8542 instantiate it, and that lookup should instantiate the enclosing
8544 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8545 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8547 base_list = NULL_TREE;
8548 if (BINFO_N_BASE_BINFOS (pbinfo))
8554 /* We must enter the scope containing the type, as that is where
8555 the accessibility of types named in dependent bases are
8557 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8559 /* Substitute into each of the bases to determine the actual
8561 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8564 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8565 tree expanded_bases = NULL_TREE;
8568 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8571 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8572 args, tf_error, NULL_TREE);
8573 if (expanded_bases == error_mark_node)
8576 len = TREE_VEC_LENGTH (expanded_bases);
8579 for (idx = 0; idx < len; idx++)
8582 /* Extract the already-expanded base class. */
8583 base = TREE_VEC_ELT (expanded_bases, idx);
8585 /* Substitute to figure out the base class. */
8586 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8589 if (base == error_mark_node)
8592 base_list = tree_cons (access, base, base_list);
8593 if (BINFO_VIRTUAL_P (pbase_binfo))
8594 TREE_TYPE (base_list) = integer_type_node;
8598 /* The list is now in reverse order; correct that. */
8599 base_list = nreverse (base_list);
8602 pop_scope (pushed_scope);
8604 /* Now call xref_basetypes to set up all the base-class
8606 xref_basetypes (type, base_list);
8608 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8609 (int) ATTR_FLAG_TYPE_IN_PLACE,
8610 args, tf_error, NULL_TREE);
8611 fixup_attribute_variants (type);
8613 /* Now that our base classes are set up, enter the scope of the
8614 class, so that name lookups into base classes, etc. will work
8615 correctly. This is precisely analogous to what we do in
8616 begin_class_definition when defining an ordinary non-template
8617 class, except we also need to push the enclosing classes. */
8618 push_nested_class (type);
8620 /* Now members are processed in the order of declaration. */
8621 for (member = CLASSTYPE_DECL_LIST (pattern);
8622 member; member = TREE_CHAIN (member))
8624 tree t = TREE_VALUE (member);
8626 if (TREE_PURPOSE (member))
8630 /* Build new CLASSTYPE_NESTED_UTDS. */
8633 bool class_template_p;
8635 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8636 && TYPE_LANG_SPECIFIC (t)
8637 && CLASSTYPE_IS_TEMPLATE (t));
8638 /* If the member is a class template, then -- even after
8639 substitution -- there may be dependent types in the
8640 template argument list for the class. We increment
8641 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8642 that function will assume that no types are dependent
8643 when outside of a template. */
8644 if (class_template_p)
8645 ++processing_template_decl;
8646 newtag = tsubst (t, args, tf_error, NULL_TREE);
8647 if (class_template_p)
8648 --processing_template_decl;
8649 if (newtag == error_mark_node)
8652 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8654 tree name = TYPE_IDENTIFIER (t);
8656 if (class_template_p)
8657 /* Unfortunately, lookup_template_class sets
8658 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8659 instantiation (i.e., for the type of a member
8660 template class nested within a template class.)
8661 This behavior is required for
8662 maybe_process_partial_specialization to work
8663 correctly, but is not accurate in this case;
8664 the TAG is not an instantiation of anything.
8665 (The corresponding TEMPLATE_DECL is an
8666 instantiation, but the TYPE is not.) */
8667 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8669 /* Now, we call pushtag to put this NEWTAG into the scope of
8670 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8671 pushtag calling push_template_decl. We don't have to do
8672 this for enums because it will already have been done in
8675 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8676 pushtag (name, newtag, /*tag_scope=*/ts_current);
8679 else if (TREE_CODE (t) == FUNCTION_DECL
8680 || DECL_FUNCTION_TEMPLATE_P (t))
8682 /* Build new TYPE_METHODS. */
8685 if (TREE_CODE (t) == TEMPLATE_DECL)
8686 ++processing_template_decl;
8687 r = tsubst (t, args, tf_error, NULL_TREE);
8688 if (TREE_CODE (t) == TEMPLATE_DECL)
8689 --processing_template_decl;
8690 set_current_access_from_decl (r);
8691 finish_member_declaration (r);
8692 /* Instantiate members marked with attribute used. */
8693 if (r != error_mark_node && DECL_PRESERVE_P (r))
8698 /* Build new TYPE_FIELDS. */
8699 if (TREE_CODE (t) == STATIC_ASSERT)
8702 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8703 tf_warning_or_error, NULL_TREE,
8704 /*integral_constant_expression_p=*/true);
8705 finish_static_assert (condition,
8706 STATIC_ASSERT_MESSAGE (t),
8707 STATIC_ASSERT_SOURCE_LOCATION (t),
8710 else if (TREE_CODE (t) != CONST_DECL)
8714 /* The file and line for this declaration, to
8715 assist in error message reporting. Since we
8716 called push_tinst_level above, we don't need to
8718 input_location = DECL_SOURCE_LOCATION (t);
8720 if (TREE_CODE (t) == TEMPLATE_DECL)
8721 ++processing_template_decl;
8722 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8723 if (TREE_CODE (t) == TEMPLATE_DECL)
8724 --processing_template_decl;
8725 if (TREE_CODE (r) == VAR_DECL)
8729 [t]he initialization (and any associated
8730 side-effects) of a static data member does
8731 not occur unless the static data member is
8732 itself used in a way that requires the
8733 definition of the static data member to
8736 Therefore, we do not substitute into the
8737 initialized for the static data member here. */
8738 finish_static_data_member_decl
8741 /*init_const_expr_p=*/false,
8742 /*asmspec_tree=*/NULL_TREE,
8744 /* Instantiate members marked with attribute used. */
8745 if (r != error_mark_node && DECL_PRESERVE_P (r))
8748 else if (TREE_CODE (r) == FIELD_DECL)
8750 /* Determine whether R has a valid type and can be
8751 completed later. If R is invalid, then it is
8752 replaced by error_mark_node so that it will not be
8753 added to TYPE_FIELDS. */
8754 tree rtype = TREE_TYPE (r);
8755 if (can_complete_type_without_circularity (rtype))
8756 complete_type (rtype);
8758 if (!COMPLETE_TYPE_P (rtype))
8760 cxx_incomplete_type_error (r, rtype);
8761 r = error_mark_node;
8765 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8766 such a thing will already have been added to the field
8767 list by tsubst_enum in finish_member_declaration in the
8768 CLASSTYPE_NESTED_UTDS case above. */
8769 if (!(TREE_CODE (r) == TYPE_DECL
8770 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8771 && DECL_ARTIFICIAL (r)))
8773 set_current_access_from_decl (r);
8774 finish_member_declaration (r);
8781 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8783 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8785 tree friend_type = t;
8786 bool adjust_processing_template_decl = false;
8788 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8790 /* template <class T> friend class C; */
8791 friend_type = tsubst_friend_class (friend_type, args);
8792 adjust_processing_template_decl = true;
8794 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8796 /* template <class T> friend class C::D; */
8797 friend_type = tsubst (friend_type, args,
8798 tf_warning_or_error, NULL_TREE);
8799 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8800 friend_type = TREE_TYPE (friend_type);
8801 adjust_processing_template_decl = true;
8803 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8804 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8806 /* This could be either
8810 when dependent_type_p is false or
8812 template <class U> friend class T::C;
8815 friend_type = tsubst (friend_type, args,
8816 tf_warning_or_error, NULL_TREE);
8817 /* Bump processing_template_decl for correct
8818 dependent_type_p calculation. */
8819 ++processing_template_decl;
8820 if (dependent_type_p (friend_type))
8821 adjust_processing_template_decl = true;
8822 --processing_template_decl;
8824 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8825 && hidden_name_p (TYPE_NAME (friend_type)))
8829 where C hasn't been declared yet. Let's lookup name
8830 from namespace scope directly, bypassing any name that
8831 come from dependent base class. */
8832 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8834 /* The call to xref_tag_from_type does injection for friend
8836 push_nested_namespace (ns);
8838 xref_tag_from_type (friend_type, NULL_TREE,
8839 /*tag_scope=*/ts_current);
8840 pop_nested_namespace (ns);
8842 else if (uses_template_parms (friend_type))
8843 /* friend class C<T>; */
8844 friend_type = tsubst (friend_type, args,
8845 tf_warning_or_error, NULL_TREE);
8850 where C is already declared or
8852 friend class C<int>;
8854 We don't have to do anything in these cases. */
8856 if (adjust_processing_template_decl)
8857 /* Trick make_friend_class into realizing that the friend
8858 we're adding is a template, not an ordinary class. It's
8859 important that we use make_friend_class since it will
8860 perform some error-checking and output cross-reference
8862 ++processing_template_decl;
8864 if (friend_type != error_mark_node)
8865 make_friend_class (type, friend_type, /*complain=*/false);
8867 if (adjust_processing_template_decl)
8868 --processing_template_decl;
8872 /* Build new DECL_FRIENDLIST. */
8875 /* The file and line for this declaration, to
8876 assist in error message reporting. Since we
8877 called push_tinst_level above, we don't need to
8879 input_location = DECL_SOURCE_LOCATION (t);
8881 if (TREE_CODE (t) == TEMPLATE_DECL)
8883 ++processing_template_decl;
8884 push_deferring_access_checks (dk_no_check);
8887 r = tsubst_friend_function (t, args);
8888 add_friend (type, r, /*complain=*/false);
8889 if (TREE_CODE (t) == TEMPLATE_DECL)
8891 pop_deferring_access_checks ();
8892 --processing_template_decl;
8898 if (CLASSTYPE_LAMBDA_EXPR (type))
8900 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
8901 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
8903 apply_lambda_return_type (lambda, void_type_node);
8904 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
8906 instantiate_decl (lambda_function (type), false, false);
8907 maybe_add_lambda_conv_op (type);
8910 /* Set the file and line number information to whatever is given for
8911 the class itself. This puts error messages involving generated
8912 implicit functions at a predictable point, and the same point
8913 that would be used for non-template classes. */
8914 input_location = DECL_SOURCE_LOCATION (typedecl);
8916 unreverse_member_declarations (type);
8917 finish_struct_1 (type);
8918 TYPE_BEING_DEFINED (type) = 0;
8920 /* We don't instantiate default arguments for member functions. 14.7.1:
8922 The implicit instantiation of a class template specialization causes
8923 the implicit instantiation of the declarations, but not of the
8924 definitions or default arguments, of the class member functions,
8925 member classes, static data members and member templates.... */
8927 /* Some typedefs referenced from within the template code need to be access
8928 checked at template instantiation time, i.e now. These types were
8929 added to the template at parsing time. Let's get those and perform
8930 the access checks then. */
8931 perform_typedefs_access_check (pattern, args);
8932 perform_deferred_access_checks ();
8933 pop_nested_class ();
8934 maximum_field_alignment = saved_maximum_field_alignment;
8935 pop_from_top_level ();
8936 pop_deferring_access_checks ();
8939 /* The vtable for a template class can be emitted in any translation
8940 unit in which the class is instantiated. When there is no key
8941 method, however, finish_struct_1 will already have added TYPE to
8942 the keyed_classes list. */
8943 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8944 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8949 /* Wrapper for instantiate_class_template_1. */
8952 instantiate_class_template (tree type)
8955 timevar_push (TV_TEMPLATE_INST);
8956 ret = instantiate_class_template_1 (type);
8957 timevar_pop (TV_TEMPLATE_INST);
8962 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8968 else if (TYPE_P (t))
8969 r = tsubst (t, args, complain, in_decl);
8972 if (!(complain & tf_warning))
8973 ++c_inhibit_evaluation_warnings;
8974 r = tsubst_expr (t, args, complain, in_decl,
8975 /*integral_constant_expression_p=*/true);
8976 if (!(complain & tf_warning))
8977 --c_inhibit_evaluation_warnings;
8978 /* Preserve the raw-reference nature of T. */
8979 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
8980 && REFERENCE_REF_P (r))
8981 r = TREE_OPERAND (r, 0);
8986 /* Given a function parameter pack TMPL_PARM and some function parameters
8987 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
8988 and set *SPEC_P to point at the next point in the list. */
8991 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
8993 /* Collect all of the extra "packed" parameters into an
8997 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8998 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8999 tree spec_parm = *spec_p;
9002 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9004 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9007 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9008 parmvec = make_tree_vec (len);
9009 parmtypevec = make_tree_vec (len);
9010 spec_parm = *spec_p;
9011 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9013 TREE_VEC_ELT (parmvec, i) = spec_parm;
9014 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9017 /* Build the argument packs. */
9018 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9019 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9020 TREE_TYPE (argpack) = argtypepack;
9021 *spec_p = spec_parm;
9026 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9027 NONTYPE_ARGUMENT_PACK. */
9030 make_fnparm_pack (tree spec_parm)
9032 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9035 /* Substitute ARGS into T, which is an pack expansion
9036 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9037 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9038 (if only a partial substitution could be performed) or
9039 ERROR_MARK_NODE if there was an error. */
9041 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9045 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
9049 htab_t saved_local_specializations = NULL;
9051 gcc_assert (PACK_EXPANSION_P (t));
9052 pattern = PACK_EXPANSION_PATTERN (t);
9054 /* Determine the argument packs that will instantiate the parameter
9055 packs used in the expansion expression. While we're at it,
9056 compute the number of arguments to be expanded and make sure it
9058 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9059 pack = TREE_CHAIN (pack))
9061 tree parm_pack = TREE_VALUE (pack);
9062 tree arg_pack = NULL_TREE;
9063 tree orig_arg = NULL_TREE;
9065 if (TREE_CODE (parm_pack) == PARM_DECL)
9067 if (!cp_unevaluated_operand)
9068 arg_pack = retrieve_local_specialization (parm_pack);
9071 /* We can't rely on local_specializations for a parameter
9072 name used later in a function declaration (such as in a
9073 late-specified return type). Even if it exists, it might
9074 have the wrong value for a recursive call. Just make a
9075 dummy decl, since it's only used for its type. */
9076 arg_pack = tsubst_decl (parm_pack, args, complain);
9077 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9078 /* Partial instantiation of the parm_pack, we can't build
9079 up an argument pack yet. */
9080 arg_pack = NULL_TREE;
9082 arg_pack = make_fnparm_pack (arg_pack);
9087 int level, idx, levels;
9088 template_parm_level_and_index (parm_pack, &level, &idx);
9090 levels = TMPL_ARGS_DEPTH (args);
9091 if (level <= levels)
9092 arg_pack = TMPL_ARG (args, level, idx);
9095 orig_arg = arg_pack;
9096 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9097 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9099 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9100 /* This can only happen if we forget to expand an argument
9101 pack somewhere else. Just return an error, silently. */
9103 result = make_tree_vec (1);
9104 TREE_VEC_ELT (result, 0) = error_mark_node;
9108 /* For clarity in the comments below let's use the
9109 representation 'argument_pack<elements>' to denote an
9110 argument pack and its elements.
9112 In the 'if' block below, we want to detect cases where
9113 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
9114 check if ARG_PACK is an argument pack which sole element is
9115 the expansion of PARM_PACK. That argument pack is typically
9116 created by template_parm_to_arg when passed a parameter
9119 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9120 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
9122 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
9123 tree pattern = PACK_EXPANSION_PATTERN (expansion);
9124 /* So we have an argument_pack<P...>. We want to test if P
9125 is actually PARM_PACK. We will not use cp_tree_equal to
9126 test P and PARM_PACK because during type fixup (by
9127 fixup_template_parm) P can be a pre-fixup version of a
9128 type and PARM_PACK be its post-fixup version.
9129 cp_tree_equal would consider them as different even
9130 though we would want to consider them compatible for our
9131 precise purpose here.
9133 Thus we are going to consider that P and PARM_PACK are
9134 compatible if they have the same DECL. */
9135 if ((/* If ARG_PACK is a type parameter pack named by the
9136 same DECL as parm_pack ... */
9138 && TYPE_P (parm_pack)
9139 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
9140 /* ... or if ARG_PACK is a non-type parameter
9141 named by the same DECL as parm_pack ... */
9142 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
9143 && TREE_CODE (parm_pack) == PARM_DECL
9144 && TEMPLATE_PARM_DECL (pattern)
9145 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
9146 && template_parameter_pack_p (pattern))
9147 /* ... then the argument pack that the parameter maps to
9148 is just an expansion of the parameter itself, such as
9149 one would find in the implicit typedef of a class
9150 inside the class itself. Consider this parameter
9151 "unsubstituted", so that we will maintain the outer
9153 arg_pack = NULL_TREE;
9159 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9161 /* It's all-or-nothing with incomplete argument packs. */
9162 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9163 return error_mark_node;
9165 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9170 else if (len != my_len)
9173 /* We got explicit args for some packs but not others;
9174 do nothing now and try again after deduction. */
9176 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9177 error ("mismatched argument pack lengths while expanding "
9181 error ("mismatched argument pack lengths while expanding "
9184 return error_mark_node;
9187 /* Keep track of the parameter packs and their corresponding
9189 packs = tree_cons (parm_pack, arg_pack, packs);
9190 TREE_TYPE (packs) = orig_arg;
9193 /* We can't substitute for this parameter pack. */
9194 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
9196 unsubstituted_packs);
9199 /* We cannot expand this expansion expression, because we don't have
9200 all of the argument packs we need. Substitute into the pattern
9201 and return a PACK_EXPANSION_*. The caller will need to deal with
9203 if (unsubstituted_packs)
9206 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9207 new_pat = tsubst_expr (pattern, args, complain, in_decl,
9208 /*integral_constant_expression_p=*/false);
9210 new_pat = tsubst (pattern, args, complain, in_decl);
9211 return make_pack_expansion (new_pat);
9214 /* We could not find any argument packs that work. */
9216 return error_mark_node;
9218 if (cp_unevaluated_operand)
9220 /* We're in a late-specified return type, so create our own local
9221 specializations table; the current table is either NULL or (in the
9222 case of recursive unification) might have bindings that we don't
9223 want to use or alter. */
9224 saved_local_specializations = local_specializations;
9225 local_specializations = htab_create (37,
9226 hash_local_specialization,
9227 eq_local_specializations,
9231 /* For each argument in each argument pack, substitute into the
9233 result = make_tree_vec (len + incomplete);
9234 for (i = 0; i < len + incomplete; ++i)
9236 /* For parameter pack, change the substitution of the parameter
9237 pack to the ith argument in its argument pack, then expand
9239 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9241 tree parm = TREE_PURPOSE (pack);
9243 if (TREE_CODE (parm) == PARM_DECL)
9245 /* Select the Ith argument from the pack. */
9246 tree arg = make_node (ARGUMENT_PACK_SELECT);
9247 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9248 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9250 register_local_specialization (arg, parm);
9256 template_parm_level_and_index (parm, &level, &idx);
9260 /* Select the Ith argument from the pack. */
9261 value = make_node (ARGUMENT_PACK_SELECT);
9262 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
9263 ARGUMENT_PACK_SELECT_INDEX (value) = i;
9266 /* Update the corresponding argument. */
9267 TMPL_ARG (args, level, idx) = value;
9271 /* Substitute into the PATTERN with the altered arguments. */
9272 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9273 TREE_VEC_ELT (result, i) =
9274 tsubst_expr (pattern, args, complain, in_decl,
9275 /*integral_constant_expression_p=*/false);
9277 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9280 /* When we have incomplete argument packs, the last "expanded"
9281 result is itself a pack expansion, which allows us
9282 to deduce more arguments. */
9283 TREE_VEC_ELT (result, i) =
9284 make_pack_expansion (TREE_VEC_ELT (result, i));
9286 if (TREE_VEC_ELT (result, i) == error_mark_node)
9288 result = error_mark_node;
9293 /* Update ARGS to restore the substitution from parameter packs to
9294 their argument packs. */
9295 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9297 tree parm = TREE_PURPOSE (pack);
9299 if (TREE_CODE (parm) == PARM_DECL)
9300 register_local_specialization (TREE_TYPE (pack), parm);
9304 template_parm_level_and_index (parm, &level, &idx);
9306 /* Update the corresponding argument. */
9307 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9308 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9311 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9315 if (saved_local_specializations)
9317 htab_delete (local_specializations);
9318 local_specializations = saved_local_specializations;
9324 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9325 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9326 parameter packs; all parms generated from a function parameter pack will
9327 have the same DECL_PARM_INDEX. */
9330 get_pattern_parm (tree parm, tree tmpl)
9332 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9335 if (DECL_ARTIFICIAL (parm))
9337 for (patparm = DECL_ARGUMENTS (pattern);
9338 patparm; patparm = DECL_CHAIN (patparm))
9339 if (DECL_ARTIFICIAL (patparm)
9340 && DECL_NAME (parm) == DECL_NAME (patparm))
9345 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9346 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9347 gcc_assert (DECL_PARM_INDEX (patparm)
9348 == DECL_PARM_INDEX (parm));
9354 /* Substitute ARGS into the vector or list of template arguments T. */
9357 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9360 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9363 if (t == error_mark_node)
9364 return error_mark_node;
9366 len = TREE_VEC_LENGTH (t);
9367 elts = XALLOCAVEC (tree, len);
9369 for (i = 0; i < len; i++)
9371 tree orig_arg = TREE_VEC_ELT (t, i);
9374 if (TREE_CODE (orig_arg) == TREE_VEC)
9375 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9376 else if (PACK_EXPANSION_P (orig_arg))
9378 /* Substitute into an expansion expression. */
9379 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9381 if (TREE_CODE (new_arg) == TREE_VEC)
9382 /* Add to the expanded length adjustment the number of
9383 expanded arguments. We subtract one from this
9384 measurement, because the argument pack expression
9385 itself is already counted as 1 in
9386 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9387 the argument pack is empty. */
9388 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9390 else if (ARGUMENT_PACK_P (orig_arg))
9392 /* Substitute into each of the arguments. */
9393 new_arg = TYPE_P (orig_arg)
9394 ? cxx_make_type (TREE_CODE (orig_arg))
9395 : make_node (TREE_CODE (orig_arg));
9397 SET_ARGUMENT_PACK_ARGS (
9399 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9400 args, complain, in_decl));
9402 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9403 new_arg = error_mark_node;
9405 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9406 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9408 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9410 if (TREE_TYPE (new_arg) == error_mark_node)
9411 new_arg = error_mark_node;
9415 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9417 if (new_arg == error_mark_node)
9418 return error_mark_node;
9421 if (new_arg != orig_arg)
9428 /* Make space for the expanded arguments coming from template
9430 t = make_tree_vec (len + expanded_len_adjust);
9431 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9432 arguments for a member template.
9433 In that case each TREE_VEC in ORIG_T represents a level of template
9434 arguments, and ORIG_T won't carry any non defaulted argument count.
9435 It will rather be the nested TREE_VECs that will carry one.
9436 In other words, ORIG_T carries a non defaulted argument count only
9437 if it doesn't contain any nested TREE_VEC. */
9438 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9440 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9441 count += expanded_len_adjust;
9442 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9444 for (i = 0, out = 0; i < len; i++)
9446 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9447 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9448 && TREE_CODE (elts[i]) == TREE_VEC)
9452 /* Now expand the template argument pack "in place". */
9453 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9454 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9458 TREE_VEC_ELT (t, out) = elts[i];
9466 /* Return the result of substituting ARGS into the template parameters
9467 given by PARMS. If there are m levels of ARGS and m + n levels of
9468 PARMS, then the result will contain n levels of PARMS. For
9469 example, if PARMS is `template <class T> template <class U>
9470 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9471 result will be `template <int*, double, class V>'. */
9474 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9479 /* When substituting into a template, we must set
9480 PROCESSING_TEMPLATE_DECL as the template parameters may be
9481 dependent if they are based on one-another, and the dependency
9482 predicates are short-circuit outside of templates. */
9483 ++processing_template_decl;
9485 for (new_parms = &r;
9486 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9487 new_parms = &(TREE_CHAIN (*new_parms)),
9488 parms = TREE_CHAIN (parms))
9491 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9494 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9498 if (parms == error_mark_node)
9501 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9503 if (tuple == error_mark_node)
9506 TREE_VEC_ELT (new_vec, i) =
9507 tsubst_template_parm (tuple, args, complain);
9511 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9512 - TMPL_ARGS_DEPTH (args)),
9513 new_vec, NULL_TREE);
9516 --processing_template_decl;
9521 /* Return the result of substituting ARGS into one template parameter
9522 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9523 parameter and which TREE_PURPOSE is the default argument of the
9524 template parameter. */
9527 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9529 tree default_value, parm_decl;
9531 if (args == NULL_TREE
9533 || t == error_mark_node)
9536 gcc_assert (TREE_CODE (t) == TREE_LIST);
9538 default_value = TREE_PURPOSE (t);
9539 parm_decl = TREE_VALUE (t);
9541 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9542 if (TREE_CODE (parm_decl) == PARM_DECL
9543 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9544 parm_decl = error_mark_node;
9545 default_value = tsubst_template_arg (default_value, args,
9546 complain, NULL_TREE);
9548 return build_tree_list (default_value, parm_decl);
9551 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9552 type T. If T is not an aggregate or enumeration type, it is
9553 handled as if by tsubst. IN_DECL is as for tsubst. If
9554 ENTERING_SCOPE is nonzero, T is the context for a template which
9555 we are presently tsubst'ing. Return the substituted value. */
9558 tsubst_aggr_type (tree t,
9560 tsubst_flags_t complain,
9567 switch (TREE_CODE (t))
9570 if (TYPE_PTRMEMFUNC_P (t))
9571 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9573 /* Else fall through. */
9576 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9581 int saved_unevaluated_operand;
9582 int saved_inhibit_evaluation_warnings;
9584 /* In "sizeof(X<I>)" we need to evaluate "I". */
9585 saved_unevaluated_operand = cp_unevaluated_operand;
9586 cp_unevaluated_operand = 0;
9587 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9588 c_inhibit_evaluation_warnings = 0;
9590 /* First, determine the context for the type we are looking
9592 context = TYPE_CONTEXT (t);
9593 if (context && TYPE_P (context))
9595 context = tsubst_aggr_type (context, args, complain,
9596 in_decl, /*entering_scope=*/1);
9597 /* If context is a nested class inside a class template,
9598 it may still need to be instantiated (c++/33959). */
9599 context = complete_type (context);
9602 /* Then, figure out what arguments are appropriate for the
9603 type we are trying to find. For example, given:
9605 template <class T> struct S;
9606 template <class T, class U> void f(T, U) { S<U> su; }
9608 and supposing that we are instantiating f<int, double>,
9609 then our ARGS will be {int, double}, but, when looking up
9610 S we only want {double}. */
9611 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9613 if (argvec == error_mark_node)
9614 r = error_mark_node;
9617 r = lookup_template_class (t, argvec, in_decl, context,
9618 entering_scope, complain);
9619 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9622 cp_unevaluated_operand = saved_unevaluated_operand;
9623 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9628 /* This is not a template type, so there's nothing to do. */
9632 return tsubst (t, args, complain, in_decl);
9636 /* Substitute into the default argument ARG (a default argument for
9637 FN), which has the indicated TYPE. */
9640 tsubst_default_argument (tree fn, tree type, tree arg)
9642 tree saved_class_ptr = NULL_TREE;
9643 tree saved_class_ref = NULL_TREE;
9645 /* This can happen in invalid code. */
9646 if (TREE_CODE (arg) == DEFAULT_ARG)
9649 /* This default argument came from a template. Instantiate the
9650 default argument here, not in tsubst. In the case of
9659 we must be careful to do name lookup in the scope of S<T>,
9660 rather than in the current class. */
9661 push_access_scope (fn);
9662 /* The "this" pointer is not valid in a default argument. */
9665 saved_class_ptr = current_class_ptr;
9666 cp_function_chain->x_current_class_ptr = NULL_TREE;
9667 saved_class_ref = current_class_ref;
9668 cp_function_chain->x_current_class_ref = NULL_TREE;
9671 push_deferring_access_checks(dk_no_deferred);
9672 /* The default argument expression may cause implicitly defined
9673 member functions to be synthesized, which will result in garbage
9674 collection. We must treat this situation as if we were within
9675 the body of function so as to avoid collecting live data on the
9678 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9679 tf_warning_or_error, NULL_TREE,
9680 /*integral_constant_expression_p=*/false);
9682 pop_deferring_access_checks();
9684 /* Restore the "this" pointer. */
9687 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9688 cp_function_chain->x_current_class_ref = saved_class_ref;
9691 /* Make sure the default argument is reasonable. */
9692 arg = check_default_argument (type, arg);
9694 pop_access_scope (fn);
9699 /* Substitute into all the default arguments for FN. */
9702 tsubst_default_arguments (tree fn)
9707 tmpl_args = DECL_TI_ARGS (fn);
9709 /* If this function is not yet instantiated, we certainly don't need
9710 its default arguments. */
9711 if (uses_template_parms (tmpl_args))
9713 /* Don't do this again for clones. */
9714 if (DECL_CLONED_FUNCTION_P (fn))
9717 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9719 arg = TREE_CHAIN (arg))
9720 if (TREE_PURPOSE (arg))
9721 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9723 TREE_PURPOSE (arg));
9726 /* Substitute the ARGS into the T, which is a _DECL. Return the
9727 result of the substitution. Issue error and warning messages under
9728 control of COMPLAIN. */
9731 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9733 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9734 location_t saved_loc;
9739 /* Set the filename and linenumber to improve error-reporting. */
9740 saved_loc = input_location;
9741 input_location = DECL_SOURCE_LOCATION (t);
9743 switch (TREE_CODE (t))
9747 /* We can get here when processing a member function template,
9748 member class template, or template template parameter. */
9749 tree decl = DECL_TEMPLATE_RESULT (t);
9754 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9756 /* Template template parameter is treated here. */
9757 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9758 if (new_type == error_mark_node)
9759 RETURN (error_mark_node);
9762 DECL_CHAIN (r) = NULL_TREE;
9763 TREE_TYPE (r) = new_type;
9764 DECL_TEMPLATE_RESULT (r)
9765 = build_decl (DECL_SOURCE_LOCATION (decl),
9766 TYPE_DECL, DECL_NAME (decl), new_type);
9767 DECL_TEMPLATE_PARMS (r)
9768 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9770 TYPE_NAME (new_type) = r;
9774 /* We might already have an instance of this template.
9775 The ARGS are for the surrounding class type, so the
9776 full args contain the tsubst'd args for the context,
9777 plus the innermost args from the template decl. */
9778 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9779 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9780 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9781 /* Because this is a template, the arguments will still be
9782 dependent, even after substitution. If
9783 PROCESSING_TEMPLATE_DECL is not set, the dependency
9784 predicates will short-circuit. */
9785 ++processing_template_decl;
9786 full_args = tsubst_template_args (tmpl_args, args,
9788 --processing_template_decl;
9789 if (full_args == error_mark_node)
9790 RETURN (error_mark_node);
9792 /* If this is a default template template argument,
9793 tsubst might not have changed anything. */
9794 if (full_args == tmpl_args)
9797 hash = hash_tmpl_and_args (t, full_args);
9798 spec = retrieve_specialization (t, full_args, hash);
9799 if (spec != NULL_TREE)
9805 /* Make a new template decl. It will be similar to the
9806 original, but will record the current template arguments.
9807 We also create a new function declaration, which is just
9808 like the old one, but points to this new template, rather
9809 than the old one. */
9811 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9812 DECL_CHAIN (r) = NULL_TREE;
9814 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9816 if (TREE_CODE (decl) == TYPE_DECL)
9819 ++processing_template_decl;
9820 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9821 --processing_template_decl;
9822 if (new_type == error_mark_node)
9823 RETURN (error_mark_node);
9825 TREE_TYPE (r) = new_type;
9826 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9827 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9828 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9829 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9834 ++processing_template_decl;
9835 new_decl = tsubst (decl, args, complain, in_decl);
9836 --processing_template_decl;
9837 if (new_decl == error_mark_node)
9838 RETURN (error_mark_node);
9840 DECL_TEMPLATE_RESULT (r) = new_decl;
9841 DECL_TI_TEMPLATE (new_decl) = r;
9842 TREE_TYPE (r) = TREE_TYPE (new_decl);
9843 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9844 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9847 SET_DECL_IMPLICIT_INSTANTIATION (r);
9848 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9849 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9851 /* The template parameters for this new template are all the
9852 template parameters for the old template, except the
9853 outermost level of parameters. */
9854 DECL_TEMPLATE_PARMS (r)
9855 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9858 if (PRIMARY_TEMPLATE_P (t))
9859 DECL_PRIMARY_TEMPLATE (r) = r;
9861 if (TREE_CODE (decl) != TYPE_DECL)
9862 /* Record this non-type partial instantiation. */
9863 register_specialization (r, t,
9864 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9872 tree argvec = NULL_TREE;
9880 /* Nobody should be tsubst'ing into non-template functions. */
9881 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9883 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9888 /* If T is not dependent, just return it. We have to
9889 increment PROCESSING_TEMPLATE_DECL because
9890 value_dependent_expression_p assumes that nothing is
9891 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9892 ++processing_template_decl;
9893 dependent_p = value_dependent_expression_p (t);
9894 --processing_template_decl;
9898 /* Calculate the most general template of which R is a
9899 specialization, and the complete set of arguments used to
9901 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9902 argvec = tsubst_template_args (DECL_TI_ARGS
9903 (DECL_TEMPLATE_RESULT
9904 (DECL_TI_TEMPLATE (t))),
9905 args, complain, in_decl);
9906 if (argvec == error_mark_node)
9907 RETURN (error_mark_node);
9909 /* Check to see if we already have this specialization. */
9910 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9911 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9919 /* We can see more levels of arguments than parameters if
9920 there was a specialization of a member template, like
9923 template <class T> struct S { template <class U> void f(); }
9924 template <> template <class U> void S<int>::f(U);
9926 Here, we'll be substituting into the specialization,
9927 because that's where we can find the code we actually
9928 want to generate, but we'll have enough arguments for
9929 the most general template.
9931 We also deal with the peculiar case:
9933 template <class T> struct S {
9934 template <class U> friend void f();
9936 template <class U> void f() {}
9938 template void f<double>();
9940 Here, the ARGS for the instantiation of will be {int,
9941 double}. But, we only need as many ARGS as there are
9942 levels of template parameters in CODE_PATTERN. We are
9943 careful not to get fooled into reducing the ARGS in
9946 template <class T> struct S { template <class U> void f(U); }
9947 template <class T> template <> void S<T>::f(int) {}
9949 which we can spot because the pattern will be a
9950 specialization in this case. */
9951 args_depth = TMPL_ARGS_DEPTH (args);
9953 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9954 if (args_depth > parms_depth
9955 && !DECL_TEMPLATE_SPECIALIZATION (t))
9956 args = get_innermost_template_args (args, parms_depth);
9960 /* This special case arises when we have something like this:
9962 template <class T> struct S {
9963 friend void f<int>(int, double);
9966 Here, the DECL_TI_TEMPLATE for the friend declaration
9967 will be an IDENTIFIER_NODE. We are being called from
9968 tsubst_friend_function, and we want only to create a
9969 new decl (R) with appropriate types so that we can call
9970 determine_specialization. */
9971 gen_tmpl = NULL_TREE;
9974 if (DECL_CLASS_SCOPE_P (t))
9976 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9980 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9981 complain, t, /*entering_scope=*/1);
9986 ctx = DECL_CONTEXT (t);
9988 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9989 if (type == error_mark_node)
9990 RETURN (error_mark_node);
9992 /* We do NOT check for matching decls pushed separately at this
9993 point, as they may not represent instantiations of this
9994 template, and in any case are considered separate under the
9997 DECL_USE_TEMPLATE (r) = 0;
9998 TREE_TYPE (r) = type;
9999 /* Clear out the mangled name and RTL for the instantiation. */
10000 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10001 SET_DECL_RTL (r, NULL);
10002 /* Leave DECL_INITIAL set on deleted instantiations. */
10003 if (!DECL_DELETED_FN (r))
10004 DECL_INITIAL (r) = NULL_TREE;
10005 DECL_CONTEXT (r) = ctx;
10007 if (member && DECL_CONV_FN_P (r))
10008 /* Type-conversion operator. Reconstruct the name, in
10009 case it's the name of one of the template's parameters. */
10010 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10012 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10014 DECL_RESULT (r) = NULL_TREE;
10016 TREE_STATIC (r) = 0;
10017 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10018 DECL_EXTERNAL (r) = 1;
10019 /* If this is an instantiation of a function with internal
10020 linkage, we already know what object file linkage will be
10021 assigned to the instantiation. */
10022 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10023 DECL_DEFER_OUTPUT (r) = 0;
10024 DECL_CHAIN (r) = NULL_TREE;
10025 DECL_PENDING_INLINE_INFO (r) = 0;
10026 DECL_PENDING_INLINE_P (r) = 0;
10027 DECL_SAVED_TREE (r) = NULL_TREE;
10028 DECL_STRUCT_FUNCTION (r) = NULL;
10030 /* We'll re-clone as appropriate in instantiate_template. */
10031 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10033 /* If we aren't complaining now, return on error before we register
10034 the specialization so that we'll complain eventually. */
10035 if ((complain & tf_error) == 0
10036 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10037 && !grok_op_properties (r, /*complain=*/false))
10038 RETURN (error_mark_node);
10040 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10041 this in the special friend case mentioned above where
10042 GEN_TMPL is NULL. */
10045 DECL_TEMPLATE_INFO (r)
10046 = build_template_info (gen_tmpl, argvec);
10047 SET_DECL_IMPLICIT_INSTANTIATION (r);
10048 register_specialization (r, gen_tmpl, argvec, false, hash);
10050 /* We're not supposed to instantiate default arguments
10051 until they are called, for a template. But, for a
10054 template <class T> void f ()
10055 { extern void g(int i = T()); }
10057 we should do the substitution when the template is
10058 instantiated. We handle the member function case in
10059 instantiate_class_template since the default arguments
10060 might refer to other members of the class. */
10062 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10063 && !uses_template_parms (argvec))
10064 tsubst_default_arguments (r);
10067 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10069 /* Copy the list of befriending classes. */
10070 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10072 friends = &TREE_CHAIN (*friends))
10074 *friends = copy_node (*friends);
10075 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10080 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10082 maybe_retrofit_in_chrg (r);
10083 if (DECL_CONSTRUCTOR_P (r))
10084 grok_ctor_properties (ctx, r);
10085 /* If this is an instantiation of a member template, clone it.
10086 If it isn't, that'll be handled by
10087 clone_constructors_and_destructors. */
10088 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10089 clone_function_decl (r, /*update_method_vec_p=*/0);
10091 else if ((complain & tf_error) != 0
10092 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10093 && !grok_op_properties (r, /*complain=*/true))
10094 RETURN (error_mark_node);
10096 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10097 SET_DECL_FRIEND_CONTEXT (r,
10098 tsubst (DECL_FRIEND_CONTEXT (t),
10099 args, complain, in_decl));
10101 /* Possibly limit visibility based on template args. */
10102 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10103 if (DECL_VISIBILITY_SPECIFIED (t))
10105 DECL_VISIBILITY_SPECIFIED (r) = 0;
10106 DECL_ATTRIBUTES (r)
10107 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10109 determine_visibility (r);
10110 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10111 && !processing_template_decl)
10112 defaulted_late_check (r);
10114 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10115 args, complain, in_decl);
10121 tree type = NULL_TREE;
10123 tree expanded_types = NULL_TREE;
10124 tree prev_r = NULL_TREE;
10125 tree first_r = NULL_TREE;
10127 if (FUNCTION_PARAMETER_PACK_P (t))
10129 /* If there is a local specialization that isn't a
10130 parameter pack, it means that we're doing a "simple"
10131 substitution from inside tsubst_pack_expansion. Just
10132 return the local specialization (which will be a single
10134 tree spec = retrieve_local_specialization (t);
10136 && TREE_CODE (spec) == PARM_DECL
10137 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10140 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10141 the parameters in this function parameter pack. */
10142 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10143 complain, in_decl);
10144 if (TREE_CODE (expanded_types) == TREE_VEC)
10146 len = TREE_VEC_LENGTH (expanded_types);
10148 /* Zero-length parameter packs are boring. Just substitute
10151 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10156 /* All we did was update the type. Make a note of that. */
10157 type = expanded_types;
10158 expanded_types = NULL_TREE;
10162 /* Loop through all of the parameter's we'll build. When T is
10163 a function parameter pack, LEN is the number of expanded
10164 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10166 for (i = 0; i < len; ++i)
10170 if (DECL_TEMPLATE_PARM_P (t))
10171 SET_DECL_TEMPLATE_PARM_P (r);
10173 if (expanded_types)
10174 /* We're on the Ith parameter of the function parameter
10177 /* An argument of a function parameter pack is not a parameter
10179 FUNCTION_PARAMETER_PACK_P (r) = false;
10181 /* Get the Ith type. */
10182 type = TREE_VEC_ELT (expanded_types, i);
10185 /* Rename the parameter to include the index. */
10187 make_ith_pack_parameter_name (DECL_NAME (r), i);
10190 /* We're dealing with a normal parameter. */
10191 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10193 type = type_decays_to (type);
10194 TREE_TYPE (r) = type;
10195 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10197 if (DECL_INITIAL (r))
10199 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10200 DECL_INITIAL (r) = TREE_TYPE (r);
10202 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10203 complain, in_decl);
10206 DECL_CONTEXT (r) = NULL_TREE;
10208 if (!DECL_TEMPLATE_PARM_P (r))
10209 DECL_ARG_TYPE (r) = type_passed_as (type);
10211 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10212 args, complain, in_decl);
10214 /* Keep track of the first new parameter we
10215 generate. That's what will be returned to the
10220 /* Build a proper chain of parameters when substituting
10221 into a function parameter pack. */
10223 DECL_CHAIN (prev_r) = r;
10226 if (DECL_CHAIN (t))
10227 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10228 complain, DECL_CHAIN (t));
10230 /* FIRST_R contains the start of the chain we've built. */
10240 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10241 if (type == error_mark_node)
10242 RETURN (error_mark_node);
10243 TREE_TYPE (r) = type;
10244 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10246 /* DECL_INITIAL gives the number of bits in a bit-field. */
10248 = tsubst_expr (DECL_INITIAL (t), args,
10250 /*integral_constant_expression_p=*/true);
10251 /* We don't have to set DECL_CONTEXT here; it is set by
10252 finish_member_declaration. */
10253 DECL_CHAIN (r) = NULL_TREE;
10254 if (VOID_TYPE_P (type))
10255 error ("instantiation of %q+D as type %qT", r, type);
10257 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10258 args, complain, in_decl);
10263 /* We reach here only for member using decls. */
10264 if (DECL_DEPENDENT_P (t))
10266 r = do_class_using_decl
10267 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10268 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10270 r = error_mark_node;
10273 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10274 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10280 DECL_CHAIN (r) = NULL_TREE;
10287 tree argvec = NULL_TREE;
10288 tree gen_tmpl = NULL_TREE;
10290 tree tmpl = NULL_TREE;
10292 tree type = NULL_TREE;
10295 if (TREE_CODE (t) == TYPE_DECL
10296 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10298 /* If this is the canonical decl, we don't have to
10299 mess with instantiations, and often we can't (for
10300 typename, template type parms and such). Note that
10301 TYPE_NAME is not correct for the above test if
10302 we've copied the type for a typedef. */
10303 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10304 if (type == error_mark_node)
10305 RETURN (error_mark_node);
10306 r = TYPE_NAME (type);
10310 /* Check to see if we already have the specialization we
10313 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10315 /* T is a static data member or namespace-scope entity.
10316 We have to substitute into namespace-scope variables
10317 (even though such entities are never templates) because
10320 template <class T> void f() { extern T t; }
10322 where the entity referenced is not known until
10323 instantiation time. */
10325 ctx = DECL_CONTEXT (t);
10326 if (DECL_CLASS_SCOPE_P (t))
10328 ctx = tsubst_aggr_type (ctx, args,
10330 in_decl, /*entering_scope=*/1);
10331 /* If CTX is unchanged, then T is in fact the
10332 specialization we want. That situation occurs when
10333 referencing a static data member within in its own
10334 class. We can use pointer equality, rather than
10335 same_type_p, because DECL_CONTEXT is always
10337 if (ctx == DECL_CONTEXT (t))
10343 tmpl = DECL_TI_TEMPLATE (t);
10344 gen_tmpl = most_general_template (tmpl);
10345 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10346 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10347 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10352 /* A local variable. */
10354 /* Subsequent calls to pushdecl will fill this in. */
10356 spec = retrieve_local_specialization (t);
10358 /* If we already have the specialization we need, there is
10359 nothing more to do. */
10366 /* Create a new node for the specialization we need. */
10368 if (type == NULL_TREE)
10370 if (is_typedef_decl (t))
10371 type = DECL_ORIGINAL_TYPE (t);
10373 type = TREE_TYPE (t);
10374 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10375 type = strip_array_domain (type);
10376 type = tsubst (type, args, complain, in_decl);
10378 if (TREE_CODE (r) == VAR_DECL)
10380 /* Even if the original location is out of scope, the
10381 newly substituted one is not. */
10382 DECL_DEAD_FOR_LOCAL (r) = 0;
10383 DECL_INITIALIZED_P (r) = 0;
10384 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10385 if (type == error_mark_node)
10386 RETURN (error_mark_node);
10387 if (TREE_CODE (type) == FUNCTION_TYPE)
10389 /* It may seem that this case cannot occur, since:
10394 declares a function, not a variable. However:
10397 template <typename T> void g() { T t; }
10398 template void g<f>();
10400 is an attempt to declare a variable with function
10402 error ("variable %qD has function type",
10403 /* R is not yet sufficiently initialized, so we
10404 just use its name. */
10406 RETURN (error_mark_node);
10408 type = complete_type (type);
10409 /* Wait until cp_finish_decl to set this again, to handle
10410 circular dependency (template/instantiate6.C). */
10411 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10412 type = check_var_type (DECL_NAME (r), type);
10414 if (DECL_HAS_VALUE_EXPR_P (t))
10416 tree ve = DECL_VALUE_EXPR (t);
10417 ve = tsubst_expr (ve, args, complain, in_decl,
10418 /*constant_expression_p=*/false);
10419 if (REFERENCE_REF_P (ve))
10421 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10422 ve = TREE_OPERAND (ve, 0);
10424 SET_DECL_VALUE_EXPR (r, ve);
10427 else if (DECL_SELF_REFERENCE_P (t))
10428 SET_DECL_SELF_REFERENCE_P (r);
10429 TREE_TYPE (r) = type;
10430 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10431 DECL_CONTEXT (r) = ctx;
10432 /* Clear out the mangled name and RTL for the instantiation. */
10433 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10434 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10435 SET_DECL_RTL (r, NULL);
10436 /* The initializer must not be expanded until it is required;
10437 see [temp.inst]. */
10438 DECL_INITIAL (r) = NULL_TREE;
10439 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10440 SET_DECL_RTL (r, NULL);
10441 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10442 if (TREE_CODE (r) == VAR_DECL)
10444 /* Possibly limit visibility based on template args. */
10445 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10446 if (DECL_VISIBILITY_SPECIFIED (t))
10448 DECL_VISIBILITY_SPECIFIED (r) = 0;
10449 DECL_ATTRIBUTES (r)
10450 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10452 determine_visibility (r);
10457 /* A static data member declaration is always marked
10458 external when it is declared in-class, even if an
10459 initializer is present. We mimic the non-template
10460 processing here. */
10461 DECL_EXTERNAL (r) = 1;
10463 register_specialization (r, gen_tmpl, argvec, false, hash);
10464 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10465 SET_DECL_IMPLICIT_INSTANTIATION (r);
10467 else if (cp_unevaluated_operand)
10469 /* We're substituting this var in a decltype outside of its
10470 scope, such as for a lambda return type. Don't add it to
10471 local_specializations, do perform auto deduction. */
10472 tree auto_node = type_uses_auto (type);
10476 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10477 /*constant_expression_p=*/false);
10478 init = resolve_nondeduced_context (init);
10479 TREE_TYPE (r) = type
10480 = do_auto_deduction (type, init, auto_node);
10484 register_local_specialization (r, t);
10486 DECL_CHAIN (r) = NULL_TREE;
10488 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10490 args, complain, in_decl);
10492 /* Preserve a typedef that names a type. */
10493 if (is_typedef_decl (r))
10495 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10496 set_underlying_type (r);
10499 layout_decl (r, 0);
10504 gcc_unreachable ();
10509 /* Restore the file and line information. */
10510 input_location = saved_loc;
10515 /* Substitute into the ARG_TYPES of a function type. */
10518 tsubst_arg_types (tree arg_types,
10520 tsubst_flags_t complain,
10523 tree remaining_arg_types;
10524 tree type = NULL_TREE;
10526 tree expanded_args = NULL_TREE;
10529 if (!arg_types || arg_types == void_list_node)
10532 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10533 args, complain, in_decl);
10534 if (remaining_arg_types == error_mark_node)
10535 return error_mark_node;
10537 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10539 /* For a pack expansion, perform substitution on the
10540 entire expression. Later on, we'll handle the arguments
10542 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10543 args, complain, in_decl);
10545 if (TREE_CODE (expanded_args) == TREE_VEC)
10546 /* So that we'll spin through the parameters, one by one. */
10547 i = TREE_VEC_LENGTH (expanded_args);
10550 /* We only partially substituted into the parameter
10551 pack. Our type is TYPE_PACK_EXPANSION. */
10552 type = expanded_args;
10553 expanded_args = NULL_TREE;
10561 type = TREE_VEC_ELT (expanded_args, i);
10563 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10565 if (type == error_mark_node)
10566 return error_mark_node;
10567 if (VOID_TYPE_P (type))
10569 if (complain & tf_error)
10571 error ("invalid parameter type %qT", type);
10573 error ("in declaration %q+D", in_decl);
10575 return error_mark_node;
10578 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10579 top-level qualifiers as required. */
10580 type = cv_unqualified (type_decays_to (type));
10582 /* We do not substitute into default arguments here. The standard
10583 mandates that they be instantiated only when needed, which is
10584 done in build_over_call. */
10585 default_arg = TREE_PURPOSE (arg_types);
10587 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10589 /* We've instantiated a template before its default arguments
10590 have been parsed. This can happen for a nested template
10591 class, and is not an error unless we require the default
10592 argument in a call of this function. */
10593 remaining_arg_types =
10594 tree_cons (default_arg, type, remaining_arg_types);
10595 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10596 remaining_arg_types);
10599 remaining_arg_types =
10600 hash_tree_cons (default_arg, type, remaining_arg_types);
10603 return remaining_arg_types;
10606 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10607 *not* handle the exception-specification for FNTYPE, because the
10608 initial substitution of explicitly provided template parameters
10609 during argument deduction forbids substitution into the
10610 exception-specification:
10614 All references in the function type of the function template to the
10615 corresponding template parameters are replaced by the specified tem-
10616 plate argument values. If a substitution in a template parameter or
10617 in the function type of the function template results in an invalid
10618 type, type deduction fails. [Note: The equivalent substitution in
10619 exception specifications is done only when the function is instanti-
10620 ated, at which point a program is ill-formed if the substitution
10621 results in an invalid type.] */
10624 tsubst_function_type (tree t,
10626 tsubst_flags_t complain,
10633 /* The TYPE_CONTEXT is not used for function/method types. */
10634 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10636 /* Substitute the return type. */
10637 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10638 if (return_type == error_mark_node)
10639 return error_mark_node;
10640 /* The standard does not presently indicate that creation of a
10641 function type with an invalid return type is a deduction failure.
10642 However, that is clearly analogous to creating an array of "void"
10643 or a reference to a reference. This is core issue #486. */
10644 if (TREE_CODE (return_type) == ARRAY_TYPE
10645 || TREE_CODE (return_type) == FUNCTION_TYPE)
10647 if (complain & tf_error)
10649 if (TREE_CODE (return_type) == ARRAY_TYPE)
10650 error ("function returning an array");
10652 error ("function returning a function");
10654 return error_mark_node;
10657 /* Substitute the argument types. */
10658 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10659 complain, in_decl);
10660 if (arg_types == error_mark_node)
10661 return error_mark_node;
10663 /* Construct a new type node and return it. */
10664 if (TREE_CODE (t) == FUNCTION_TYPE)
10666 fntype = build_function_type (return_type, arg_types);
10667 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10671 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10672 if (! MAYBE_CLASS_TYPE_P (r))
10676 Type deduction may fail for any of the following
10679 -- Attempting to create "pointer to member of T" when T
10680 is not a class type. */
10681 if (complain & tf_error)
10682 error ("creating pointer to member function of non-class type %qT",
10684 return error_mark_node;
10687 fntype = build_method_type_directly (r, return_type,
10688 TREE_CHAIN (arg_types));
10690 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10695 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10696 ARGS into that specification, and return the substituted
10697 specification. If there is no specification, return NULL_TREE. */
10700 tsubst_exception_specification (tree fntype,
10702 tsubst_flags_t complain,
10709 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10710 new_specs = NULL_TREE;
10711 if (specs && TREE_PURPOSE (specs))
10713 /* A noexcept-specifier. */
10714 tree expr = TREE_PURPOSE (specs);
10715 if (expr == boolean_true_node || expr == boolean_false_node)
10719 /* Defer instantiation of noexcept-specifiers to avoid
10720 excessive instantiations (c++/49107). */
10721 new_specs = make_node (DEFERRED_NOEXCEPT);
10722 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
10724 /* We already partially instantiated this member template,
10725 so combine the new args with the old. */
10726 DEFERRED_NOEXCEPT_PATTERN (new_specs)
10727 = DEFERRED_NOEXCEPT_PATTERN (expr);
10728 DEFERRED_NOEXCEPT_ARGS (new_specs)
10729 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
10733 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
10734 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
10738 new_specs = tsubst_copy_and_build
10739 (expr, args, complain, in_decl, /*function_p=*/false,
10740 /*integral_constant_expression_p=*/true);
10741 new_specs = build_noexcept_spec (new_specs, complain);
10745 if (! TREE_VALUE (specs))
10752 tree expanded_specs = NULL_TREE;
10754 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10756 /* Expand the pack expansion type. */
10757 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10761 if (expanded_specs == error_mark_node)
10762 return error_mark_node;
10763 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10764 len = TREE_VEC_LENGTH (expanded_specs);
10767 /* We're substituting into a member template, so
10768 we got a TYPE_PACK_EXPANSION back. Add that
10769 expansion and move on. */
10770 gcc_assert (TREE_CODE (expanded_specs)
10771 == TYPE_PACK_EXPANSION);
10772 new_specs = add_exception_specifier (new_specs,
10775 specs = TREE_CHAIN (specs);
10780 for (i = 0; i < len; ++i)
10782 if (expanded_specs)
10783 spec = TREE_VEC_ELT (expanded_specs, i);
10785 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10786 if (spec == error_mark_node)
10788 new_specs = add_exception_specifier (new_specs, spec,
10792 specs = TREE_CHAIN (specs);
10798 /* Take the tree structure T and replace template parameters used
10799 therein with the argument vector ARGS. IN_DECL is an associated
10800 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10801 Issue error and warning messages under control of COMPLAIN. Note
10802 that we must be relatively non-tolerant of extensions here, in
10803 order to preserve conformance; if we allow substitutions that
10804 should not be allowed, we may allow argument deductions that should
10805 not succeed, and therefore report ambiguous overload situations
10806 where there are none. In theory, we could allow the substitution,
10807 but indicate that it should have failed, and allow our caller to
10808 make sure that the right thing happens, but we don't try to do this
10811 This function is used for dealing with types, decls and the like;
10812 for expressions, use tsubst_expr or tsubst_copy. */
10815 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10817 enum tree_code code;
10820 if (t == NULL_TREE || t == error_mark_node
10821 || t == integer_type_node
10822 || t == void_type_node
10823 || t == char_type_node
10824 || t == unknown_type_node
10825 || TREE_CODE (t) == NAMESPACE_DECL
10826 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10830 return tsubst_decl (t, args, complain);
10832 if (args == NULL_TREE)
10835 code = TREE_CODE (t);
10837 if (code == IDENTIFIER_NODE)
10838 type = IDENTIFIER_TYPE_VALUE (t);
10840 type = TREE_TYPE (t);
10842 gcc_assert (type != unknown_type_node);
10844 /* Reuse typedefs. We need to do this to handle dependent attributes,
10845 such as attribute aligned. */
10847 && typedef_variant_p (t))
10849 tree decl = TYPE_NAME (t);
10851 if (DECL_CLASS_SCOPE_P (decl)
10852 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10853 && uses_template_parms (DECL_CONTEXT (decl)))
10855 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10856 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10857 r = retrieve_specialization (tmpl, gen_args, 0);
10859 else if (DECL_FUNCTION_SCOPE_P (decl)
10860 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10861 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10862 r = retrieve_local_specialization (decl);
10864 /* The typedef is from a non-template context. */
10870 r = cp_build_qualified_type_real
10871 (r, cp_type_quals (t) | cp_type_quals (r),
10872 complain | tf_ignore_bad_quals);
10875 /* Else we must be instantiating the typedef, so fall through. */
10879 && code != TYPENAME_TYPE
10880 && code != TEMPLATE_TYPE_PARM
10881 && code != IDENTIFIER_NODE
10882 && code != FUNCTION_TYPE
10883 && code != METHOD_TYPE)
10884 type = tsubst (type, args, complain, in_decl);
10885 if (type == error_mark_node)
10886 return error_mark_node;
10892 case ENUMERAL_TYPE:
10893 return tsubst_aggr_type (t, args, complain, in_decl,
10894 /*entering_scope=*/0);
10897 case IDENTIFIER_NODE:
10908 if (t == integer_type_node)
10911 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10912 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10916 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10918 max = tsubst_expr (omax, args, complain, in_decl,
10919 /*integral_constant_expression_p=*/false);
10921 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10923 if (TREE_CODE (max) == NOP_EXPR
10924 && TREE_SIDE_EFFECTS (omax)
10925 && !TREE_TYPE (max))
10926 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10928 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10929 with TREE_SIDE_EFFECTS that indicates this is not an integral
10930 constant expression. */
10931 if (processing_template_decl
10932 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10934 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10935 TREE_SIDE_EFFECTS (max) = 1;
10938 return compute_array_index_type (NULL_TREE, max, complain);
10941 case TEMPLATE_TYPE_PARM:
10942 case TEMPLATE_TEMPLATE_PARM:
10943 case BOUND_TEMPLATE_TEMPLATE_PARM:
10944 case TEMPLATE_PARM_INDEX:
10949 tree arg = NULL_TREE;
10953 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10954 template_parm_level_and_index (t, &level, &idx);
10956 levels = TMPL_ARGS_DEPTH (args);
10957 if (level <= levels)
10959 arg = TMPL_ARG (args, level, idx);
10961 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10962 /* See through ARGUMENT_PACK_SELECT arguments. */
10963 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10966 if (arg == error_mark_node)
10967 return error_mark_node;
10968 else if (arg != NULL_TREE)
10970 if (ARGUMENT_PACK_P (arg))
10971 /* If ARG is an argument pack, we don't actually want to
10972 perform a substitution here, because substitutions
10973 for argument packs are only done
10974 element-by-element. We can get to this point when
10975 substituting the type of a non-type template
10976 parameter pack, when that type actually contains
10977 template parameter packs from an outer template, e.g.,
10979 template<typename... Types> struct A {
10980 template<Types... Values> struct B { };
10984 if (code == TEMPLATE_TYPE_PARM)
10987 gcc_assert (TYPE_P (arg));
10989 quals = cp_type_quals (arg) | cp_type_quals (t);
10991 return cp_build_qualified_type_real
10992 (arg, quals, complain | tf_ignore_bad_quals);
10994 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
10996 /* We are processing a type constructed from a
10997 template template parameter. */
10998 tree argvec = tsubst (TYPE_TI_ARGS (t),
10999 args, complain, in_decl);
11000 if (argvec == error_mark_node)
11001 return error_mark_node;
11003 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11004 are resolving nested-types in the signature of a
11005 member function templates. Otherwise ARG is a
11006 TEMPLATE_DECL and is the real template to be
11008 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11009 arg = TYPE_NAME (arg);
11011 r = lookup_template_class (arg,
11013 DECL_CONTEXT (arg),
11014 /*entering_scope=*/0,
11016 return cp_build_qualified_type_real
11017 (r, cp_type_quals (t), complain);
11020 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11021 return convert_from_reference (unshare_expr (arg));
11025 /* This can happen during the attempted tsubst'ing in
11026 unify. This means that we don't yet have any information
11027 about the template parameter in question. */
11030 /* If we get here, we must have been looking at a parm for a
11031 more deeply nested template. Make a new version of this
11032 template parameter, but with a lower level. */
11035 case TEMPLATE_TYPE_PARM:
11036 case TEMPLATE_TEMPLATE_PARM:
11037 case BOUND_TEMPLATE_TEMPLATE_PARM:
11038 if (cp_type_quals (t))
11040 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11041 r = cp_build_qualified_type_real
11042 (r, cp_type_quals (t),
11043 complain | (code == TEMPLATE_TYPE_PARM
11044 ? tf_ignore_bad_quals : 0));
11049 TEMPLATE_TYPE_PARM_INDEX (r)
11050 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11051 r, levels, args, complain);
11052 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11053 TYPE_MAIN_VARIANT (r) = r;
11054 TYPE_POINTER_TO (r) = NULL_TREE;
11055 TYPE_REFERENCE_TO (r) = NULL_TREE;
11057 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11058 /* We have reduced the level of the template
11059 template parameter, but not the levels of its
11060 template parameters, so canonical_type_parameter
11061 will not be able to find the canonical template
11062 template parameter for this level. Thus, we
11063 require structural equality checking to compare
11064 TEMPLATE_TEMPLATE_PARMs. */
11065 SET_TYPE_STRUCTURAL_EQUALITY (r);
11066 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11067 SET_TYPE_STRUCTURAL_EQUALITY (r);
11069 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11071 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11073 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11074 complain, in_decl);
11075 if (argvec == error_mark_node)
11076 return error_mark_node;
11078 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11079 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11084 case TEMPLATE_PARM_INDEX:
11085 r = reduce_template_parm_level (t, type, levels, args, complain);
11089 gcc_unreachable ();
11097 tree purpose, value, chain;
11099 if (t == void_list_node)
11102 purpose = TREE_PURPOSE (t);
11105 purpose = tsubst (purpose, args, complain, in_decl);
11106 if (purpose == error_mark_node)
11107 return error_mark_node;
11109 value = TREE_VALUE (t);
11112 value = tsubst (value, args, complain, in_decl);
11113 if (value == error_mark_node)
11114 return error_mark_node;
11116 chain = TREE_CHAIN (t);
11117 if (chain && chain != void_type_node)
11119 chain = tsubst (chain, args, complain, in_decl);
11120 if (chain == error_mark_node)
11121 return error_mark_node;
11123 if (purpose == TREE_PURPOSE (t)
11124 && value == TREE_VALUE (t)
11125 && chain == TREE_CHAIN (t))
11127 return hash_tree_cons (purpose, value, chain);
11131 /* We should never be tsubsting a binfo. */
11132 gcc_unreachable ();
11135 /* A vector of template arguments. */
11136 gcc_assert (!type);
11137 return tsubst_template_args (t, args, complain, in_decl);
11140 case REFERENCE_TYPE:
11142 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11147 Type deduction may fail for any of the following
11150 -- Attempting to create a pointer to reference type.
11151 -- Attempting to create a reference to a reference type or
11152 a reference to void.
11154 Core issue 106 says that creating a reference to a reference
11155 during instantiation is no longer a cause for failure. We
11156 only enforce this check in strict C++98 mode. */
11157 if ((TREE_CODE (type) == REFERENCE_TYPE
11158 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11159 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11161 static location_t last_loc;
11163 /* We keep track of the last time we issued this error
11164 message to avoid spewing a ton of messages during a
11165 single bad template instantiation. */
11166 if (complain & tf_error
11167 && last_loc != input_location)
11169 if (TREE_CODE (type) == VOID_TYPE)
11170 error ("forming reference to void");
11171 else if (code == POINTER_TYPE)
11172 error ("forming pointer to reference type %qT", type);
11174 error ("forming reference to reference type %qT", type);
11175 last_loc = input_location;
11178 return error_mark_node;
11180 else if (code == POINTER_TYPE)
11182 r = build_pointer_type (type);
11183 if (TREE_CODE (type) == METHOD_TYPE)
11184 r = build_ptrmemfunc_type (r);
11186 else if (TREE_CODE (type) == REFERENCE_TYPE)
11187 /* In C++0x, during template argument substitution, when there is an
11188 attempt to create a reference to a reference type, reference
11189 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11191 "If a template-argument for a template-parameter T names a type
11192 that is a reference to a type A, an attempt to create the type
11193 'lvalue reference to cv T' creates the type 'lvalue reference to
11194 A,' while an attempt to create the type type rvalue reference to
11195 cv T' creates the type T"
11197 r = cp_build_reference_type
11199 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11201 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11202 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11204 if (r != error_mark_node)
11205 /* Will this ever be needed for TYPE_..._TO values? */
11212 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11213 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11217 Type deduction may fail for any of the following
11220 -- Attempting to create "pointer to member of T" when T
11221 is not a class type. */
11222 if (complain & tf_error)
11223 error ("creating pointer to member of non-class type %qT", r);
11224 return error_mark_node;
11226 if (TREE_CODE (type) == REFERENCE_TYPE)
11228 if (complain & tf_error)
11229 error ("creating pointer to member reference type %qT", type);
11230 return error_mark_node;
11232 if (TREE_CODE (type) == VOID_TYPE)
11234 if (complain & tf_error)
11235 error ("creating pointer to member of type void");
11236 return error_mark_node;
11238 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11239 if (TREE_CODE (type) == FUNCTION_TYPE)
11241 /* The type of the implicit object parameter gets its
11242 cv-qualifiers from the FUNCTION_TYPE. */
11244 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11245 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11246 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11250 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11254 case FUNCTION_TYPE:
11259 fntype = tsubst_function_type (t, args, complain, in_decl);
11260 if (fntype == error_mark_node)
11261 return error_mark_node;
11263 /* Substitute the exception specification. */
11264 specs = tsubst_exception_specification (t, args, complain,
11265 in_decl, /*defer_ok*/true);
11266 if (specs == error_mark_node)
11267 return error_mark_node;
11269 fntype = build_exception_variant (fntype, specs);
11274 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11275 if (domain == error_mark_node)
11276 return error_mark_node;
11278 /* As an optimization, we avoid regenerating the array type if
11279 it will obviously be the same as T. */
11280 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11283 /* These checks should match the ones in grokdeclarator.
11287 The deduction may fail for any of the following reasons:
11289 -- Attempting to create an array with an element type that
11290 is void, a function type, or a reference type, or [DR337]
11291 an abstract class type. */
11292 if (TREE_CODE (type) == VOID_TYPE
11293 || TREE_CODE (type) == FUNCTION_TYPE
11294 || TREE_CODE (type) == REFERENCE_TYPE)
11296 if (complain & tf_error)
11297 error ("creating array of %qT", type);
11298 return error_mark_node;
11300 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11302 if (complain & tf_error)
11303 error ("creating array of %qT, which is an abstract class type",
11305 return error_mark_node;
11308 r = build_cplus_array_type (type, domain);
11310 if (TYPE_USER_ALIGN (t))
11312 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11313 TYPE_USER_ALIGN (r) = 1;
11319 case TYPENAME_TYPE:
11321 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11322 in_decl, /*entering_scope=*/1);
11323 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11324 complain, in_decl);
11326 if (ctx == error_mark_node || f == error_mark_node)
11327 return error_mark_node;
11329 if (!MAYBE_CLASS_TYPE_P (ctx))
11331 if (complain & tf_error)
11332 error ("%qT is not a class, struct, or union type", ctx);
11333 return error_mark_node;
11335 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11337 /* Normally, make_typename_type does not require that the CTX
11338 have complete type in order to allow things like:
11340 template <class T> struct S { typename S<T>::X Y; };
11342 But, such constructs have already been resolved by this
11343 point, so here CTX really should have complete type, unless
11344 it's a partial instantiation. */
11345 ctx = complete_type (ctx);
11346 if (!COMPLETE_TYPE_P (ctx))
11348 if (complain & tf_error)
11349 cxx_incomplete_type_error (NULL_TREE, ctx);
11350 return error_mark_node;
11354 f = make_typename_type (ctx, f, typename_type,
11355 (complain & tf_error) | tf_keep_type_decl);
11356 if (f == error_mark_node)
11358 if (TREE_CODE (f) == TYPE_DECL)
11360 complain |= tf_ignore_bad_quals;
11364 if (TREE_CODE (f) != TYPENAME_TYPE)
11366 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11368 if (complain & tf_error)
11369 error ("%qT resolves to %qT, which is not an enumeration type",
11372 return error_mark_node;
11374 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11376 if (complain & tf_error)
11377 error ("%qT resolves to %qT, which is is not a class type",
11380 return error_mark_node;
11384 return cp_build_qualified_type_real
11385 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11388 case UNBOUND_CLASS_TEMPLATE:
11390 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11391 in_decl, /*entering_scope=*/1);
11392 tree name = TYPE_IDENTIFIER (t);
11393 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11395 if (ctx == error_mark_node || name == error_mark_node)
11396 return error_mark_node;
11399 parm_list = tsubst_template_parms (parm_list, args, complain);
11400 return make_unbound_class_template (ctx, name, parm_list, complain);
11407 ++cp_unevaluated_operand;
11408 ++c_inhibit_evaluation_warnings;
11410 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11412 /*integral_constant_expression_p=*/false);
11414 --cp_unevaluated_operand;
11415 --c_inhibit_evaluation_warnings;
11417 type = finish_typeof (type);
11418 return cp_build_qualified_type_real (type,
11420 | cp_type_quals (type),
11424 case DECLTYPE_TYPE:
11428 ++cp_unevaluated_operand;
11429 ++c_inhibit_evaluation_warnings;
11431 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11433 /*integral_constant_expression_p=*/false);
11435 --cp_unevaluated_operand;
11436 --c_inhibit_evaluation_warnings;
11438 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11439 type = lambda_capture_field_type (type);
11440 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11441 type = lambda_proxy_type (type);
11443 type = finish_decltype_type
11444 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11445 return cp_build_qualified_type_real (type,
11447 | cp_type_quals (type),
11451 case UNDERLYING_TYPE:
11453 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11454 complain, in_decl);
11455 return finish_underlying_type (type);
11458 case TYPE_ARGUMENT_PACK:
11459 case NONTYPE_ARGUMENT_PACK:
11461 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11463 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11467 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11469 /* For template nontype argument packs, also substitute into
11471 if (code == NONTYPE_ARGUMENT_PACK)
11472 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11490 /* We should use one of the expression tsubsts for these codes. */
11491 gcc_unreachable ();
11494 sorry ("use of %qs in template", tree_code_name [(int) code]);
11495 return error_mark_node;
11499 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11500 type of the expression on the left-hand side of the "." or "->"
11504 tsubst_baselink (tree baselink, tree object_type,
11505 tree args, tsubst_flags_t complain, tree in_decl)
11508 tree qualifying_scope;
11511 tree template_args = 0;
11512 bool template_id_p = false;
11514 /* A baselink indicates a function from a base class. Both the
11515 BASELINK_ACCESS_BINFO and the base class referenced may
11516 indicate bases of the template class, rather than the
11517 instantiated class. In addition, lookups that were not
11518 ambiguous before may be ambiguous now. Therefore, we perform
11519 the lookup again. */
11520 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11521 qualifying_scope = tsubst (qualifying_scope, args,
11522 complain, in_decl);
11523 fns = BASELINK_FUNCTIONS (baselink);
11524 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11525 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11527 template_id_p = true;
11528 template_args = TREE_OPERAND (fns, 1);
11529 fns = TREE_OPERAND (fns, 0);
11531 template_args = tsubst_template_args (template_args, args,
11532 complain, in_decl);
11534 name = DECL_NAME (get_first_fn (fns));
11535 if (IDENTIFIER_TYPENAME_P (name))
11536 name = mangle_conv_op_name_for_type (optype);
11537 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11539 return error_mark_node;
11541 /* If lookup found a single function, mark it as used at this
11542 point. (If it lookup found multiple functions the one selected
11543 later by overload resolution will be marked as used at that
11545 if (BASELINK_P (baselink))
11546 fns = BASELINK_FUNCTIONS (baselink);
11547 if (!template_id_p && !really_overloaded_fn (fns))
11548 mark_used (OVL_CURRENT (fns));
11550 /* Add back the template arguments, if present. */
11551 if (BASELINK_P (baselink) && template_id_p)
11552 BASELINK_FUNCTIONS (baselink)
11553 = build_nt (TEMPLATE_ID_EXPR,
11554 BASELINK_FUNCTIONS (baselink),
11556 /* Update the conversion operator type. */
11557 BASELINK_OPTYPE (baselink) = optype;
11560 object_type = current_class_type;
11561 return adjust_result_of_qualified_name_lookup (baselink,
11566 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11567 true if the qualified-id will be a postfix-expression in-and-of
11568 itself; false if more of the postfix-expression follows the
11569 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11573 tsubst_qualified_id (tree qualified_id, tree args,
11574 tsubst_flags_t complain, tree in_decl,
11575 bool done, bool address_p)
11581 tree template_args;
11583 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11585 /* Figure out what name to look up. */
11586 name = TREE_OPERAND (qualified_id, 1);
11587 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11589 is_template = true;
11590 template_args = TREE_OPERAND (name, 1);
11592 template_args = tsubst_template_args (template_args, args,
11593 complain, in_decl);
11594 name = TREE_OPERAND (name, 0);
11598 is_template = false;
11599 template_args = NULL_TREE;
11602 /* Substitute into the qualifying scope. When there are no ARGS, we
11603 are just trying to simplify a non-dependent expression. In that
11604 case the qualifying scope may be dependent, and, in any case,
11605 substituting will not help. */
11606 scope = TREE_OPERAND (qualified_id, 0);
11609 scope = tsubst (scope, args, complain, in_decl);
11610 expr = tsubst_copy (name, args, complain, in_decl);
11615 if (dependent_scope_p (scope))
11618 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11619 return build_qualified_name (NULL_TREE, scope, expr,
11620 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11623 if (!BASELINK_P (name) && !DECL_P (expr))
11625 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11627 /* A BIT_NOT_EXPR is used to represent a destructor. */
11628 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11630 error ("qualifying type %qT does not match destructor name ~%qT",
11631 scope, TREE_OPERAND (expr, 0));
11632 expr = error_mark_node;
11635 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11636 /*is_type_p=*/0, false);
11639 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11640 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11641 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11643 if (complain & tf_error)
11645 error ("dependent-name %qE is parsed as a non-type, but "
11646 "instantiation yields a type", qualified_id);
11647 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11649 return error_mark_node;
11655 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11657 /* Remember that there was a reference to this entity. */
11661 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11663 if (complain & tf_error)
11664 qualified_name_lookup_error (scope,
11665 TREE_OPERAND (qualified_id, 1),
11666 expr, input_location);
11667 return error_mark_node;
11671 expr = lookup_template_function (expr, template_args);
11673 if (expr == error_mark_node && complain & tf_error)
11674 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11675 expr, input_location);
11676 else if (TYPE_P (scope))
11678 expr = (adjust_result_of_qualified_name_lookup
11679 (expr, scope, current_class_type));
11680 expr = (finish_qualified_id_expr
11681 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
11682 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11683 /*template_arg_p=*/false));
11686 /* Expressions do not generally have reference type. */
11687 if (TREE_CODE (expr) != SCOPE_REF
11688 /* However, if we're about to form a pointer-to-member, we just
11689 want the referenced member referenced. */
11690 && TREE_CODE (expr) != OFFSET_REF)
11691 expr = convert_from_reference (expr);
11696 /* Like tsubst, but deals with expressions. This function just replaces
11697 template parms; to finish processing the resultant expression, use
11701 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11703 enum tree_code code;
11706 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11709 code = TREE_CODE (t);
11714 r = retrieve_local_specialization (t);
11719 /* This can happen for a parameter name used later in a function
11720 declaration (such as in a late-specified return type). Just
11721 make a dummy decl, since it's only used for its type. */
11722 gcc_assert (cp_unevaluated_operand != 0);
11723 /* We copy T because want to tsubst the PARM_DECL only,
11724 not the following PARM_DECLs that are chained to T. */
11726 r = tsubst_decl (c, args, complain);
11727 /* Give it the template pattern as its context; its true context
11728 hasn't been instantiated yet and this is good enough for
11730 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11733 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11734 r = ARGUMENT_PACK_SELECT_ARG (r);
11743 if (DECL_TEMPLATE_PARM_P (t))
11744 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11745 /* There is no need to substitute into namespace-scope
11747 if (DECL_NAMESPACE_SCOPE_P (t))
11749 /* If ARGS is NULL, then T is known to be non-dependent. */
11750 if (args == NULL_TREE)
11751 return integral_constant_value (t);
11753 /* Unfortunately, we cannot just call lookup_name here.
11756 template <int I> int f() {
11758 struct S { void g() { E e = a; } };
11761 When we instantiate f<7>::S::g(), say, lookup_name is not
11762 clever enough to find f<7>::a. */
11764 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11765 /*entering_scope=*/0);
11767 for (v = TYPE_VALUES (enum_type);
11769 v = TREE_CHAIN (v))
11770 if (TREE_PURPOSE (v) == DECL_NAME (t))
11771 return TREE_VALUE (v);
11773 /* We didn't find the name. That should never happen; if
11774 name-lookup found it during preliminary parsing, we
11775 should find it again here during instantiation. */
11776 gcc_unreachable ();
11781 if (DECL_CONTEXT (t))
11785 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11786 /*entering_scope=*/1);
11787 if (ctx != DECL_CONTEXT (t))
11789 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11792 if (complain & tf_error)
11793 error ("using invalid field %qD", t);
11794 return error_mark_node;
11803 case FUNCTION_DECL:
11804 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11805 || local_variable_p (t))
11806 t = tsubst (t, args, complain, in_decl);
11811 /* An OVERLOAD will always be a non-dependent overload set; an
11812 overload set from function scope will just be represented with an
11813 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11814 gcc_assert (!uses_template_parms (t));
11818 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11820 case TEMPLATE_DECL:
11821 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11822 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11823 args, complain, in_decl);
11824 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11825 return tsubst (t, args, complain, in_decl);
11826 else if (DECL_CLASS_SCOPE_P (t)
11827 && uses_template_parms (DECL_CONTEXT (t)))
11829 /* Template template argument like the following example need
11832 template <template <class> class TT> struct C {};
11833 template <class T> struct D {
11834 template <class U> struct E {};
11839 We are processing the template argument `E' in #1 for
11840 the template instantiation #2. Originally, `E' is a
11841 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11842 have to substitute this with one having context `D<int>'. */
11844 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11845 return lookup_field (context, DECL_NAME(t), 0, false);
11848 /* Ordinary template template argument. */
11852 case REINTERPRET_CAST_EXPR:
11853 case CONST_CAST_EXPR:
11854 case STATIC_CAST_EXPR:
11855 case DYNAMIC_CAST_EXPR:
11858 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11859 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11862 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11868 ++cp_unevaluated_operand;
11869 ++c_inhibit_evaluation_warnings;
11870 /* We only want to compute the number of arguments. */
11871 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11872 complain, in_decl);
11873 --cp_unevaluated_operand;
11874 --c_inhibit_evaluation_warnings;
11876 if (TREE_CODE (expanded) == TREE_VEC)
11877 len = TREE_VEC_LENGTH (expanded);
11879 if (expanded == error_mark_node)
11880 return error_mark_node;
11881 else if (PACK_EXPANSION_P (expanded)
11882 || (TREE_CODE (expanded) == TREE_VEC
11884 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11886 if (TREE_CODE (expanded) == TREE_VEC)
11887 expanded = TREE_VEC_ELT (expanded, len - 1);
11889 if (TYPE_P (expanded))
11890 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11891 complain & tf_error);
11893 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11894 complain & tf_error);
11897 return build_int_cst (size_type_node, len);
11903 case TRUTH_NOT_EXPR:
11906 case UNARY_PLUS_EXPR: /* Unary + */
11908 case AT_ENCODE_EXPR:
11912 case REALPART_EXPR:
11913 case IMAGPART_EXPR:
11915 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11916 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11918 case COMPONENT_REF:
11923 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11924 name = TREE_OPERAND (t, 1);
11925 if (TREE_CODE (name) == BIT_NOT_EXPR)
11927 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11928 complain, in_decl);
11929 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11931 else if (TREE_CODE (name) == SCOPE_REF
11932 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11934 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11935 complain, in_decl);
11936 name = TREE_OPERAND (name, 1);
11937 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11938 complain, in_decl);
11939 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11940 name = build_qualified_name (/*type=*/NULL_TREE,
11942 /*template_p=*/false);
11944 else if (TREE_CODE (name) == BASELINK)
11945 name = tsubst_baselink (name,
11946 non_reference (TREE_TYPE (object)),
11950 name = tsubst_copy (name, args, complain, in_decl);
11951 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11957 case TRUNC_DIV_EXPR:
11958 case CEIL_DIV_EXPR:
11959 case FLOOR_DIV_EXPR:
11960 case ROUND_DIV_EXPR:
11961 case EXACT_DIV_EXPR:
11965 case TRUNC_MOD_EXPR:
11966 case FLOOR_MOD_EXPR:
11967 case TRUTH_ANDIF_EXPR:
11968 case TRUTH_ORIF_EXPR:
11969 case TRUTH_AND_EXPR:
11970 case TRUTH_OR_EXPR:
11983 case COMPOUND_EXPR:
11986 case PREDECREMENT_EXPR:
11987 case PREINCREMENT_EXPR:
11988 case POSTDECREMENT_EXPR:
11989 case POSTINCREMENT_EXPR:
11991 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11992 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11995 return build_qualified_name (/*type=*/NULL_TREE,
11996 tsubst_copy (TREE_OPERAND (t, 0),
11997 args, complain, in_decl),
11998 tsubst_copy (TREE_OPERAND (t, 1),
11999 args, complain, in_decl),
12000 QUALIFIED_NAME_IS_TEMPLATE (t));
12005 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12006 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12007 NULL_TREE, NULL_TREE);
12011 int n = VL_EXP_OPERAND_LENGTH (t);
12012 tree result = build_vl_exp (CALL_EXPR, n);
12014 for (i = 0; i < n; i++)
12015 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12016 complain, in_decl);
12022 case PSEUDO_DTOR_EXPR:
12025 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12026 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12027 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12028 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12035 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12036 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12037 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12038 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12045 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12046 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12047 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12048 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12052 case TEMPLATE_ID_EXPR:
12054 /* Substituted template arguments */
12055 tree fn = TREE_OPERAND (t, 0);
12056 tree targs = TREE_OPERAND (t, 1);
12058 fn = tsubst_copy (fn, args, complain, in_decl);
12060 targs = tsubst_template_args (targs, args, complain, in_decl);
12062 return lookup_template_function (fn, targs);
12067 tree purpose, value, chain;
12069 if (t == void_list_node)
12072 purpose = TREE_PURPOSE (t);
12074 purpose = tsubst_copy (purpose, args, complain, in_decl);
12075 value = TREE_VALUE (t);
12077 value = tsubst_copy (value, args, complain, in_decl);
12078 chain = TREE_CHAIN (t);
12079 if (chain && chain != void_type_node)
12080 chain = tsubst_copy (chain, args, complain, in_decl);
12081 if (purpose == TREE_PURPOSE (t)
12082 && value == TREE_VALUE (t)
12083 && chain == TREE_CHAIN (t))
12085 return tree_cons (purpose, value, chain);
12090 case ENUMERAL_TYPE:
12092 case TEMPLATE_TYPE_PARM:
12093 case TEMPLATE_TEMPLATE_PARM:
12094 case BOUND_TEMPLATE_TEMPLATE_PARM:
12095 case TEMPLATE_PARM_INDEX:
12097 case REFERENCE_TYPE:
12099 case FUNCTION_TYPE:
12102 case TYPENAME_TYPE:
12103 case UNBOUND_CLASS_TEMPLATE:
12105 case DECLTYPE_TYPE:
12107 return tsubst (t, args, complain, in_decl);
12109 case IDENTIFIER_NODE:
12110 if (IDENTIFIER_TYPENAME_P (t))
12112 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12113 return mangle_conv_op_name_for_type (new_type);
12119 /* This is handled by tsubst_copy_and_build. */
12120 gcc_unreachable ();
12123 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12125 tsubst (TREE_TYPE (t), args, complain, in_decl));
12127 case CLEANUP_POINT_EXPR:
12128 /* We shouldn't have built any of these during initial template
12129 generation. Instead, they should be built during instantiation
12130 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12131 gcc_unreachable ();
12135 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12136 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12137 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12138 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12139 mark_used (TREE_OPERAND (r, 1));
12142 case EXPR_PACK_EXPANSION:
12143 error ("invalid use of pack expansion expression");
12144 return error_mark_node;
12146 case NONTYPE_ARGUMENT_PACK:
12147 error ("use %<...%> to expand argument pack");
12148 return error_mark_node;
12155 /* Instantiate any typedefs in the type. */
12156 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12157 r = fold_convert (type, t);
12158 gcc_assert (TREE_CODE (r) == code);
12163 /* These can sometimes show up in a partial instantiation, but never
12164 involve template parms. */
12165 gcc_assert (!uses_template_parms (t));
12169 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12170 gcc_checking_assert (false);
12175 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12178 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12181 tree new_clauses = NULL, nc, oc;
12183 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12185 nc = copy_node (oc);
12186 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12189 switch (OMP_CLAUSE_CODE (nc))
12191 case OMP_CLAUSE_LASTPRIVATE:
12192 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12194 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12195 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12196 in_decl, /*integral_constant_expression_p=*/false);
12197 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12198 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12201 case OMP_CLAUSE_PRIVATE:
12202 case OMP_CLAUSE_SHARED:
12203 case OMP_CLAUSE_FIRSTPRIVATE:
12204 case OMP_CLAUSE_REDUCTION:
12205 case OMP_CLAUSE_COPYIN:
12206 case OMP_CLAUSE_COPYPRIVATE:
12207 case OMP_CLAUSE_IF:
12208 case OMP_CLAUSE_NUM_THREADS:
12209 case OMP_CLAUSE_SCHEDULE:
12210 case OMP_CLAUSE_COLLAPSE:
12211 case OMP_CLAUSE_FINAL:
12212 OMP_CLAUSE_OPERAND (nc, 0)
12213 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12214 in_decl, /*integral_constant_expression_p=*/false);
12216 case OMP_CLAUSE_NOWAIT:
12217 case OMP_CLAUSE_ORDERED:
12218 case OMP_CLAUSE_DEFAULT:
12219 case OMP_CLAUSE_UNTIED:
12220 case OMP_CLAUSE_MERGEABLE:
12223 gcc_unreachable ();
12227 return finish_omp_clauses (nreverse (new_clauses));
12230 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12233 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12236 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12238 tree purpose, value, chain;
12243 if (TREE_CODE (t) != TREE_LIST)
12244 return tsubst_copy_and_build (t, args, complain, in_decl,
12245 /*function_p=*/false,
12246 /*integral_constant_expression_p=*/false);
12248 if (t == void_list_node)
12251 purpose = TREE_PURPOSE (t);
12253 purpose = RECUR (purpose);
12254 value = TREE_VALUE (t);
12255 if (value && TREE_CODE (value) != LABEL_DECL)
12256 value = RECUR (value);
12257 chain = TREE_CHAIN (t);
12258 if (chain && chain != void_type_node)
12259 chain = RECUR (chain);
12260 return tree_cons (purpose, value, chain);
12264 /* Substitute one OMP_FOR iterator. */
12267 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12268 tree condv, tree incrv, tree *clauses,
12269 tree args, tsubst_flags_t complain, tree in_decl,
12270 bool integral_constant_expression_p)
12272 #define RECUR(NODE) \
12273 tsubst_expr ((NODE), args, complain, in_decl, \
12274 integral_constant_expression_p)
12275 tree decl, init, cond, incr, auto_node;
12277 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12278 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12279 decl = RECUR (TREE_OPERAND (init, 0));
12280 init = TREE_OPERAND (init, 1);
12281 auto_node = type_uses_auto (TREE_TYPE (decl));
12282 if (auto_node && init)
12284 tree init_expr = init;
12285 if (TREE_CODE (init_expr) == DECL_EXPR)
12286 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12287 init_expr = RECUR (init_expr);
12289 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12291 gcc_assert (!type_dependent_expression_p (decl));
12293 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12295 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12296 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12297 if (TREE_CODE (incr) == MODIFY_EXPR)
12298 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12299 RECUR (TREE_OPERAND (incr, 1)),
12302 incr = RECUR (incr);
12303 TREE_VEC_ELT (declv, i) = decl;
12304 TREE_VEC_ELT (initv, i) = init;
12305 TREE_VEC_ELT (condv, i) = cond;
12306 TREE_VEC_ELT (incrv, i) = incr;
12310 if (init && TREE_CODE (init) != DECL_EXPR)
12313 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12315 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12316 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12317 && OMP_CLAUSE_DECL (c) == decl)
12319 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12320 && OMP_CLAUSE_DECL (c) == decl)
12321 error ("iteration variable %qD should not be firstprivate", decl);
12322 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12323 && OMP_CLAUSE_DECL (c) == decl)
12324 error ("iteration variable %qD should not be reduction", decl);
12328 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12329 OMP_CLAUSE_DECL (c) = decl;
12330 c = finish_omp_clauses (c);
12333 OMP_CLAUSE_CHAIN (c) = *clauses;
12338 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12339 if (COMPARISON_CLASS_P (cond))
12340 cond = build2 (TREE_CODE (cond), boolean_type_node,
12341 RECUR (TREE_OPERAND (cond, 0)),
12342 RECUR (TREE_OPERAND (cond, 1)));
12344 cond = RECUR (cond);
12345 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12346 switch (TREE_CODE (incr))
12348 case PREINCREMENT_EXPR:
12349 case PREDECREMENT_EXPR:
12350 case POSTINCREMENT_EXPR:
12351 case POSTDECREMENT_EXPR:
12352 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12353 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12356 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12357 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12359 tree rhs = TREE_OPERAND (incr, 1);
12360 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12361 RECUR (TREE_OPERAND (incr, 0)),
12362 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12363 RECUR (TREE_OPERAND (rhs, 0)),
12364 RECUR (TREE_OPERAND (rhs, 1))));
12367 incr = RECUR (incr);
12370 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12371 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12373 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12374 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12375 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12376 TREE_TYPE (decl), lhs,
12377 RECUR (TREE_OPERAND (incr, 2))));
12379 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12380 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12381 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12383 tree rhs = TREE_OPERAND (incr, 2);
12384 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12385 RECUR (TREE_OPERAND (incr, 0)),
12386 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12387 RECUR (TREE_OPERAND (rhs, 0)),
12388 RECUR (TREE_OPERAND (rhs, 1))));
12391 incr = RECUR (incr);
12394 incr = RECUR (incr);
12398 TREE_VEC_ELT (declv, i) = decl;
12399 TREE_VEC_ELT (initv, i) = init;
12400 TREE_VEC_ELT (condv, i) = cond;
12401 TREE_VEC_ELT (incrv, i) = incr;
12405 /* Like tsubst_copy for expressions, etc. but also does semantic
12409 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12410 bool integral_constant_expression_p)
12412 #define RECUR(NODE) \
12413 tsubst_expr ((NODE), args, complain, in_decl, \
12414 integral_constant_expression_p)
12418 if (t == NULL_TREE || t == error_mark_node)
12421 if (EXPR_HAS_LOCATION (t))
12422 input_location = EXPR_LOCATION (t);
12423 if (STATEMENT_CODE_P (TREE_CODE (t)))
12424 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12426 switch (TREE_CODE (t))
12428 case STATEMENT_LIST:
12430 tree_stmt_iterator i;
12431 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12432 RECUR (tsi_stmt (i));
12436 case CTOR_INITIALIZER:
12437 finish_mem_initializers (tsubst_initializer_list
12438 (TREE_OPERAND (t, 0), args));
12442 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12446 tmp = RECUR (EXPR_STMT_EXPR (t));
12447 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12448 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12450 finish_expr_stmt (tmp);
12454 do_using_directive (USING_STMT_NAMESPACE (t));
12459 tree decl, pattern_decl;
12462 pattern_decl = decl = DECL_EXPR_DECL (t);
12463 if (TREE_CODE (decl) == LABEL_DECL)
12464 finish_label_decl (DECL_NAME (decl));
12465 else if (TREE_CODE (decl) == USING_DECL)
12467 tree scope = USING_DECL_SCOPE (decl);
12468 tree name = DECL_NAME (decl);
12471 scope = tsubst (scope, args, complain, in_decl);
12472 decl = lookup_qualified_name (scope, name,
12473 /*is_type_p=*/false,
12474 /*complain=*/false);
12475 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12476 qualified_name_lookup_error (scope, name, decl, input_location);
12478 do_local_using_decl (decl, scope, name);
12482 init = DECL_INITIAL (decl);
12483 decl = tsubst (decl, args, complain, in_decl);
12484 if (decl != error_mark_node)
12486 /* By marking the declaration as instantiated, we avoid
12487 trying to instantiate it. Since instantiate_decl can't
12488 handle local variables, and since we've already done
12489 all that needs to be done, that's the right thing to
12491 if (TREE_CODE (decl) == VAR_DECL)
12492 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12493 if (TREE_CODE (decl) == VAR_DECL
12494 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12495 /* Anonymous aggregates are a special case. */
12496 finish_anon_union (decl);
12499 int const_init = false;
12500 maybe_push_decl (decl);
12501 if (TREE_CODE (decl) == VAR_DECL
12502 && DECL_PRETTY_FUNCTION_P (decl))
12504 /* For __PRETTY_FUNCTION__ we have to adjust the
12506 const char *const name
12507 = cxx_printable_name (current_function_decl, 2);
12508 init = cp_fname_init (name, &TREE_TYPE (decl));
12512 tree t = RECUR (init);
12516 /* If we had an initializer but it
12517 instantiated to nothing,
12518 value-initialize the object. This will
12519 only occur when the initializer was a
12520 pack expansion where the parameter packs
12521 used in that expansion were of length
12523 init = build_value_init (TREE_TYPE (decl),
12525 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12526 init = get_target_expr_sfinae (init, complain);
12532 if (TREE_CODE (decl) == VAR_DECL)
12533 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12535 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12540 /* A DECL_EXPR can also be used as an expression, in the condition
12541 clause of an if/for/while construct. */
12546 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12547 RECUR (FOR_INIT_STMT (t));
12548 finish_for_init_stmt (stmt);
12549 tmp = RECUR (FOR_COND (t));
12550 finish_for_cond (tmp, stmt);
12551 tmp = RECUR (FOR_EXPR (t));
12552 finish_for_expr (tmp, stmt);
12553 RECUR (FOR_BODY (t));
12554 finish_for_stmt (stmt);
12557 case RANGE_FOR_STMT:
12560 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12561 decl = RANGE_FOR_DECL (t);
12562 decl = tsubst (decl, args, complain, in_decl);
12563 maybe_push_decl (decl);
12564 expr = RECUR (RANGE_FOR_EXPR (t));
12565 stmt = cp_convert_range_for (stmt, decl, expr);
12566 RECUR (RANGE_FOR_BODY (t));
12567 finish_for_stmt (stmt);
12572 stmt = begin_while_stmt ();
12573 tmp = RECUR (WHILE_COND (t));
12574 finish_while_stmt_cond (tmp, stmt);
12575 RECUR (WHILE_BODY (t));
12576 finish_while_stmt (stmt);
12580 stmt = begin_do_stmt ();
12581 RECUR (DO_BODY (t));
12582 finish_do_body (stmt);
12583 tmp = RECUR (DO_COND (t));
12584 finish_do_stmt (tmp, stmt);
12588 stmt = begin_if_stmt ();
12589 tmp = RECUR (IF_COND (t));
12590 finish_if_stmt_cond (tmp, stmt);
12591 RECUR (THEN_CLAUSE (t));
12592 finish_then_clause (stmt);
12594 if (ELSE_CLAUSE (t))
12596 begin_else_clause (stmt);
12597 RECUR (ELSE_CLAUSE (t));
12598 finish_else_clause (stmt);
12601 finish_if_stmt (stmt);
12605 if (BIND_EXPR_BODY_BLOCK (t))
12606 stmt = begin_function_body ();
12608 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12609 ? BCS_TRY_BLOCK : 0);
12611 RECUR (BIND_EXPR_BODY (t));
12613 if (BIND_EXPR_BODY_BLOCK (t))
12614 finish_function_body (stmt);
12616 finish_compound_stmt (stmt);
12620 finish_break_stmt ();
12623 case CONTINUE_STMT:
12624 finish_continue_stmt ();
12628 stmt = begin_switch_stmt ();
12629 tmp = RECUR (SWITCH_STMT_COND (t));
12630 finish_switch_cond (tmp, stmt);
12631 RECUR (SWITCH_STMT_BODY (t));
12632 finish_switch_stmt (stmt);
12635 case CASE_LABEL_EXPR:
12636 finish_case_label (EXPR_LOCATION (t),
12637 RECUR (CASE_LOW (t)),
12638 RECUR (CASE_HIGH (t)));
12643 tree decl = LABEL_EXPR_LABEL (t);
12646 label = finish_label_stmt (DECL_NAME (decl));
12647 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12648 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12653 tmp = GOTO_DESTINATION (t);
12654 if (TREE_CODE (tmp) != LABEL_DECL)
12655 /* Computed goto's must be tsubst'd into. On the other hand,
12656 non-computed gotos must not be; the identifier in question
12657 will have no binding. */
12660 tmp = DECL_NAME (tmp);
12661 finish_goto_stmt (tmp);
12665 tmp = finish_asm_stmt
12666 (ASM_VOLATILE_P (t),
12667 RECUR (ASM_STRING (t)),
12668 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12669 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12670 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12671 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12673 tree asm_expr = tmp;
12674 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12675 asm_expr = TREE_OPERAND (asm_expr, 0);
12676 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12683 stmt = begin_try_block ();
12684 RECUR (TRY_STMTS (t));
12685 finish_cleanup_try_block (stmt);
12686 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12690 tree compound_stmt = NULL_TREE;
12692 if (FN_TRY_BLOCK_P (t))
12693 stmt = begin_function_try_block (&compound_stmt);
12695 stmt = begin_try_block ();
12697 RECUR (TRY_STMTS (t));
12699 if (FN_TRY_BLOCK_P (t))
12700 finish_function_try_block (stmt);
12702 finish_try_block (stmt);
12704 RECUR (TRY_HANDLERS (t));
12705 if (FN_TRY_BLOCK_P (t))
12706 finish_function_handler_sequence (stmt, compound_stmt);
12708 finish_handler_sequence (stmt);
12714 tree decl = HANDLER_PARMS (t);
12718 decl = tsubst (decl, args, complain, in_decl);
12719 /* Prevent instantiate_decl from trying to instantiate
12720 this variable. We've already done all that needs to be
12722 if (decl != error_mark_node)
12723 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12725 stmt = begin_handler ();
12726 finish_handler_parms (decl, stmt);
12727 RECUR (HANDLER_BODY (t));
12728 finish_handler (stmt);
12733 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12736 case STATIC_ASSERT:
12739 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12742 /*integral_constant_expression_p=*/true);
12743 finish_static_assert (condition,
12744 STATIC_ASSERT_MESSAGE (t),
12745 STATIC_ASSERT_SOURCE_LOCATION (t),
12746 /*member_p=*/false);
12751 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12752 args, complain, in_decl);
12753 stmt = begin_omp_parallel ();
12754 RECUR (OMP_PARALLEL_BODY (t));
12755 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12756 = OMP_PARALLEL_COMBINED (t);
12760 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12761 args, complain, in_decl);
12762 stmt = begin_omp_task ();
12763 RECUR (OMP_TASK_BODY (t));
12764 finish_omp_task (tmp, stmt);
12769 tree clauses, body, pre_body;
12770 tree declv, initv, condv, incrv;
12773 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12774 args, complain, in_decl);
12775 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12776 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12777 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12778 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12780 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12781 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12782 &clauses, args, complain, in_decl,
12783 integral_constant_expression_p);
12785 stmt = begin_omp_structured_block ();
12787 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12788 if (TREE_VEC_ELT (initv, i) == NULL
12789 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12790 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12791 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12793 tree init = RECUR (TREE_VEC_ELT (initv, i));
12794 gcc_assert (init == TREE_VEC_ELT (declv, i));
12795 TREE_VEC_ELT (initv, i) = NULL_TREE;
12799 tree decl_expr = TREE_VEC_ELT (initv, i);
12800 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12801 gcc_assert (init != NULL);
12802 TREE_VEC_ELT (initv, i) = RECUR (init);
12803 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12805 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12808 pre_body = push_stmt_list ();
12809 RECUR (OMP_FOR_PRE_BODY (t));
12810 pre_body = pop_stmt_list (pre_body);
12812 body = push_stmt_list ();
12813 RECUR (OMP_FOR_BODY (t));
12814 body = pop_stmt_list (body);
12816 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12817 body, pre_body, clauses);
12819 add_stmt (finish_omp_structured_block (stmt));
12825 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12826 stmt = push_stmt_list ();
12827 RECUR (OMP_BODY (t));
12828 stmt = pop_stmt_list (stmt);
12831 OMP_BODY (t) = stmt;
12832 OMP_CLAUSES (t) = tmp;
12840 stmt = push_stmt_list ();
12841 RECUR (OMP_BODY (t));
12842 stmt = pop_stmt_list (stmt);
12845 OMP_BODY (t) = stmt;
12850 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12851 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
12853 tree op1 = TREE_OPERAND (t, 1);
12854 tree rhs1 = NULL_TREE;
12856 if (TREE_CODE (op1) == COMPOUND_EXPR)
12858 rhs1 = RECUR (TREE_OPERAND (op1, 0));
12859 op1 = TREE_OPERAND (op1, 1);
12861 lhs = RECUR (TREE_OPERAND (op1, 0));
12862 rhs = RECUR (TREE_OPERAND (op1, 1));
12863 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
12864 NULL_TREE, NULL_TREE, rhs1);
12868 tree op1 = TREE_OPERAND (t, 1);
12869 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
12870 tree rhs1 = NULL_TREE;
12871 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
12872 enum tree_code opcode = NOP_EXPR;
12873 if (code == OMP_ATOMIC_READ)
12875 v = RECUR (TREE_OPERAND (op1, 0));
12876 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
12878 else if (code == OMP_ATOMIC_CAPTURE_OLD
12879 || code == OMP_ATOMIC_CAPTURE_NEW)
12881 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
12882 v = RECUR (TREE_OPERAND (op1, 0));
12883 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
12884 if (TREE_CODE (op11) == COMPOUND_EXPR)
12886 rhs1 = RECUR (TREE_OPERAND (op11, 0));
12887 op11 = TREE_OPERAND (op11, 1);
12889 lhs = RECUR (TREE_OPERAND (op11, 0));
12890 rhs = RECUR (TREE_OPERAND (op11, 1));
12891 opcode = TREE_CODE (op11);
12896 lhs = RECUR (TREE_OPERAND (op1, 0));
12897 rhs = RECUR (TREE_OPERAND (op1, 1));
12899 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
12903 case EXPR_PACK_EXPANSION:
12904 error ("invalid use of pack expansion expression");
12905 return error_mark_node;
12907 case NONTYPE_ARGUMENT_PACK:
12908 error ("use %<...%> to expand argument pack");
12909 return error_mark_node;
12912 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12914 return tsubst_copy_and_build (t, args, complain, in_decl,
12915 /*function_p=*/false,
12916 integral_constant_expression_p);
12923 /* T is a postfix-expression that is not being used in a function
12924 call. Return the substituted version of T. */
12927 tsubst_non_call_postfix_expression (tree t, tree args,
12928 tsubst_flags_t complain,
12931 if (TREE_CODE (t) == SCOPE_REF)
12932 t = tsubst_qualified_id (t, args, complain, in_decl,
12933 /*done=*/false, /*address_p=*/false);
12935 t = tsubst_copy_and_build (t, args, complain, in_decl,
12936 /*function_p=*/false,
12937 /*integral_constant_expression_p=*/false);
12942 /* Like tsubst but deals with expressions and performs semantic
12943 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12946 tsubst_copy_and_build (tree t,
12948 tsubst_flags_t complain,
12951 bool integral_constant_expression_p)
12953 #define RECUR(NODE) \
12954 tsubst_copy_and_build (NODE, args, complain, in_decl, \
12955 /*function_p=*/false, \
12956 integral_constant_expression_p)
12960 if (t == NULL_TREE || t == error_mark_node)
12963 switch (TREE_CODE (t))
12967 /* Fall through. */
12968 case IDENTIFIER_NODE:
12972 bool non_integral_constant_expression_p;
12973 const char *error_msg;
12975 if (IDENTIFIER_TYPENAME_P (t))
12977 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12978 t = mangle_conv_op_name_for_type (new_type);
12981 /* Look up the name. */
12982 decl = lookup_name (t);
12984 /* By convention, expressions use ERROR_MARK_NODE to indicate
12985 failure, not NULL_TREE. */
12986 if (decl == NULL_TREE)
12987 decl = error_mark_node;
12989 decl = finish_id_expression (t, decl, NULL_TREE,
12991 integral_constant_expression_p,
12992 /*allow_non_integral_constant_expression_p=*/false,
12993 &non_integral_constant_expression_p,
12994 /*template_p=*/false,
12996 /*address_p=*/false,
12997 /*template_arg_p=*/false,
13002 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13003 decl = unqualified_name_lookup_error (decl);
13007 case TEMPLATE_ID_EXPR:
13010 tree templ = RECUR (TREE_OPERAND (t, 0));
13011 tree targs = TREE_OPERAND (t, 1);
13014 targs = tsubst_template_args (targs, args, complain, in_decl);
13016 if (TREE_CODE (templ) == COMPONENT_REF)
13018 object = TREE_OPERAND (templ, 0);
13019 templ = TREE_OPERAND (templ, 1);
13022 object = NULL_TREE;
13023 templ = lookup_template_function (templ, targs);
13026 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13027 object, templ, NULL_TREE);
13029 return baselink_for_fns (templ);
13034 tree r = RECUR (TREE_OPERAND (t, 0));
13036 if (REFERENCE_REF_P (t))
13038 /* A type conversion to reference type will be enclosed in
13039 such an indirect ref, but the substitution of the cast
13040 will have also added such an indirect ref. */
13041 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13042 r = convert_from_reference (r);
13045 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13051 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13052 RECUR (TREE_OPERAND (t, 0)));
13055 case REINTERPRET_CAST_EXPR:
13056 case CONST_CAST_EXPR:
13057 case DYNAMIC_CAST_EXPR:
13058 case STATIC_CAST_EXPR:
13063 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13064 if (integral_constant_expression_p
13065 && !cast_valid_in_integral_constant_expression_p (type))
13067 if (complain & tf_error)
13068 error ("a cast to a type other than an integral or "
13069 "enumeration type cannot appear in a constant-expression");
13070 return error_mark_node;
13073 op = RECUR (TREE_OPERAND (t, 0));
13075 switch (TREE_CODE (t))
13078 return build_functional_cast (type, op, complain);
13079 case REINTERPRET_CAST_EXPR:
13080 return build_reinterpret_cast (type, op, complain);
13081 case CONST_CAST_EXPR:
13082 return build_const_cast (type, op, complain);
13083 case DYNAMIC_CAST_EXPR:
13084 return build_dynamic_cast (type, op, complain);
13085 case STATIC_CAST_EXPR:
13086 return build_static_cast (type, op, complain);
13088 gcc_unreachable ();
13092 case POSTDECREMENT_EXPR:
13093 case POSTINCREMENT_EXPR:
13094 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13095 args, complain, in_decl);
13096 return build_x_unary_op (TREE_CODE (t), op1, complain);
13098 case PREDECREMENT_EXPR:
13099 case PREINCREMENT_EXPR:
13103 case TRUTH_NOT_EXPR:
13104 case UNARY_PLUS_EXPR: /* Unary + */
13105 case REALPART_EXPR:
13106 case IMAGPART_EXPR:
13107 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13111 op1 = TREE_OPERAND (t, 0);
13112 if (TREE_CODE (op1) == LABEL_DECL)
13113 return finish_label_address_expr (DECL_NAME (op1),
13114 EXPR_LOCATION (op1));
13115 if (TREE_CODE (op1) == SCOPE_REF)
13116 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13117 /*done=*/true, /*address_p=*/true);
13119 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13121 return build_x_unary_op (ADDR_EXPR, op1, complain);
13126 case TRUNC_DIV_EXPR:
13127 case CEIL_DIV_EXPR:
13128 case FLOOR_DIV_EXPR:
13129 case ROUND_DIV_EXPR:
13130 case EXACT_DIV_EXPR:
13134 case TRUNC_MOD_EXPR:
13135 case FLOOR_MOD_EXPR:
13136 case TRUTH_ANDIF_EXPR:
13137 case TRUTH_ORIF_EXPR:
13138 case TRUTH_AND_EXPR:
13139 case TRUTH_OR_EXPR:
13154 return build_x_binary_op
13156 RECUR (TREE_OPERAND (t, 0)),
13157 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13159 : TREE_CODE (TREE_OPERAND (t, 0))),
13160 RECUR (TREE_OPERAND (t, 1)),
13161 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13163 : TREE_CODE (TREE_OPERAND (t, 1))),
13168 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13169 /*address_p=*/false);
13171 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13172 args, complain, in_decl);
13173 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13176 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13177 return tsubst_copy (t, args, complain, in_decl);
13181 op1 = TREE_OPERAND (t, 0);
13184 /* When there are no ARGS, we are trying to evaluate a
13185 non-dependent expression from the parser. Trying to do
13186 the substitutions may not work. */
13188 op1 = TREE_TYPE (op1);
13192 ++cp_unevaluated_operand;
13193 ++c_inhibit_evaluation_warnings;
13194 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13195 /*function_p=*/false,
13196 /*integral_constant_expression_p=*/false);
13197 --cp_unevaluated_operand;
13198 --c_inhibit_evaluation_warnings;
13201 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13202 complain & tf_error);
13204 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13205 complain & tf_error);
13207 case AT_ENCODE_EXPR:
13209 op1 = TREE_OPERAND (t, 0);
13210 ++cp_unevaluated_operand;
13211 ++c_inhibit_evaluation_warnings;
13212 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13213 /*function_p=*/false,
13214 /*integral_constant_expression_p=*/false);
13215 --cp_unevaluated_operand;
13216 --c_inhibit_evaluation_warnings;
13217 return objc_build_encode_expr (op1);
13220 case NOEXCEPT_EXPR:
13221 op1 = TREE_OPERAND (t, 0);
13222 ++cp_unevaluated_operand;
13223 ++c_inhibit_evaluation_warnings;
13224 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13225 /*function_p=*/false,
13226 /*integral_constant_expression_p=*/false);
13227 --cp_unevaluated_operand;
13228 --c_inhibit_evaluation_warnings;
13229 return finish_noexcept_expr (op1, complain);
13233 tree r = build_x_modify_expr
13234 (RECUR (TREE_OPERAND (t, 0)),
13235 TREE_CODE (TREE_OPERAND (t, 1)),
13236 RECUR (TREE_OPERAND (t, 2)),
13238 /* TREE_NO_WARNING must be set if either the expression was
13239 parenthesized or it uses an operator such as >>= rather
13240 than plain assignment. In the former case, it was already
13241 set and must be copied. In the latter case,
13242 build_x_modify_expr sets it and it must not be reset
13244 if (TREE_NO_WARNING (t))
13245 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13250 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13251 args, complain, in_decl);
13252 /* Remember that there was a reference to this entity. */
13255 return build_x_arrow (op1);
13259 tree placement = RECUR (TREE_OPERAND (t, 0));
13260 tree init = RECUR (TREE_OPERAND (t, 3));
13261 VEC(tree,gc) *placement_vec;
13262 VEC(tree,gc) *init_vec;
13265 if (placement == NULL_TREE)
13266 placement_vec = NULL;
13269 placement_vec = make_tree_vector ();
13270 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13271 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13274 /* If there was an initializer in the original tree, but it
13275 instantiated to an empty list, then we should pass a
13276 non-NULL empty vector to tell build_new that it was an
13277 empty initializer() rather than no initializer. This can
13278 only happen when the initializer is a pack expansion whose
13279 parameter packs are of length zero. */
13280 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13284 init_vec = make_tree_vector ();
13285 if (init == void_zero_node)
13286 gcc_assert (init_vec != NULL);
13289 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13290 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13294 ret = build_new (&placement_vec,
13295 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13296 RECUR (TREE_OPERAND (t, 2)),
13298 NEW_EXPR_USE_GLOBAL (t),
13301 if (placement_vec != NULL)
13302 release_tree_vector (placement_vec);
13303 if (init_vec != NULL)
13304 release_tree_vector (init_vec);
13310 return delete_sanity
13311 (RECUR (TREE_OPERAND (t, 0)),
13312 RECUR (TREE_OPERAND (t, 1)),
13313 DELETE_EXPR_USE_VEC (t),
13314 DELETE_EXPR_USE_GLOBAL (t),
13317 case COMPOUND_EXPR:
13318 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13319 RECUR (TREE_OPERAND (t, 1)),
13325 VEC(tree,gc) *call_args;
13326 unsigned int nargs, i;
13331 function = CALL_EXPR_FN (t);
13332 /* When we parsed the expression, we determined whether or
13333 not Koenig lookup should be performed. */
13334 koenig_p = KOENIG_LOOKUP_P (t);
13335 if (TREE_CODE (function) == SCOPE_REF)
13337 qualified_p = true;
13338 function = tsubst_qualified_id (function, args, complain, in_decl,
13340 /*address_p=*/false);
13342 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13344 /* Do nothing; calling tsubst_copy_and_build on an identifier
13345 would incorrectly perform unqualified lookup again.
13347 Note that we can also have an IDENTIFIER_NODE if the earlier
13348 unqualified lookup found a member function; in that case
13349 koenig_p will be false and we do want to do the lookup
13350 again to find the instantiated member function.
13352 FIXME but doing that causes c++/15272, so we need to stop
13353 using IDENTIFIER_NODE in that situation. */
13354 qualified_p = false;
13358 if (TREE_CODE (function) == COMPONENT_REF)
13360 tree op = TREE_OPERAND (function, 1);
13362 qualified_p = (TREE_CODE (op) == SCOPE_REF
13363 || (BASELINK_P (op)
13364 && BASELINK_QUALIFIED_P (op)));
13367 qualified_p = false;
13369 function = tsubst_copy_and_build (function, args, complain,
13372 integral_constant_expression_p);
13374 if (BASELINK_P (function))
13375 qualified_p = true;
13378 nargs = call_expr_nargs (t);
13379 call_args = make_tree_vector ();
13380 for (i = 0; i < nargs; ++i)
13382 tree arg = CALL_EXPR_ARG (t, i);
13384 if (!PACK_EXPANSION_P (arg))
13385 VEC_safe_push (tree, gc, call_args,
13386 RECUR (CALL_EXPR_ARG (t, i)));
13389 /* Expand the pack expansion and push each entry onto
13391 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13392 if (TREE_CODE (arg) == TREE_VEC)
13394 unsigned int len, j;
13396 len = TREE_VEC_LENGTH (arg);
13397 for (j = 0; j < len; ++j)
13399 tree value = TREE_VEC_ELT (arg, j);
13400 if (value != NULL_TREE)
13401 value = convert_from_reference (value);
13402 VEC_safe_push (tree, gc, call_args, value);
13407 /* A partial substitution. Add one entry. */
13408 VEC_safe_push (tree, gc, call_args, arg);
13413 /* We do not perform argument-dependent lookup if normal
13414 lookup finds a non-function, in accordance with the
13415 expected resolution of DR 218. */
13417 && ((is_overloaded_fn (function)
13418 /* If lookup found a member function, the Koenig lookup is
13419 not appropriate, even if an unqualified-name was used
13420 to denote the function. */
13421 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13422 || TREE_CODE (function) == IDENTIFIER_NODE)
13423 /* Only do this when substitution turns a dependent call
13424 into a non-dependent call. */
13425 && type_dependent_expression_p_push (t)
13426 && !any_type_dependent_arguments_p (call_args))
13427 function = perform_koenig_lookup (function, call_args, false,
13430 if (TREE_CODE (function) == IDENTIFIER_NODE
13431 && !any_type_dependent_arguments_p (call_args))
13433 if (koenig_p && (complain & tf_warning_or_error))
13435 /* For backwards compatibility and good diagnostics, try
13436 the unqualified lookup again if we aren't in SFINAE
13438 tree unq = (tsubst_copy_and_build
13439 (function, args, complain, in_decl, true,
13440 integral_constant_expression_p));
13441 if (unq != function)
13444 if (TREE_CODE (fn) == COMPONENT_REF)
13445 fn = TREE_OPERAND (fn, 1);
13446 if (is_overloaded_fn (fn))
13447 fn = get_first_fn (fn);
13448 permerror (EXPR_LOC_OR_HERE (t),
13449 "%qD was not declared in this scope, "
13450 "and no declarations were found by "
13451 "argument-dependent lookup at the point "
13452 "of instantiation", function);
13453 if (DECL_CLASS_SCOPE_P (fn))
13455 inform (EXPR_LOC_OR_HERE (t),
13456 "declarations in dependent base %qT are "
13457 "not found by unqualified lookup",
13458 DECL_CLASS_CONTEXT (fn));
13459 if (current_class_ptr)
13460 inform (EXPR_LOC_OR_HERE (t),
13461 "use %<this->%D%> instead", function);
13463 inform (EXPR_LOC_OR_HERE (t),
13464 "use %<%T::%D%> instead",
13465 current_class_name, function);
13468 inform (0, "%q+D declared here, later in the "
13469 "translation unit", fn);
13473 if (TREE_CODE (function) == IDENTIFIER_NODE)
13475 unqualified_name_lookup_error (function);
13476 release_tree_vector (call_args);
13477 return error_mark_node;
13481 /* Remember that there was a reference to this entity. */
13482 if (DECL_P (function))
13483 mark_used (function);
13485 if (TREE_CODE (function) == OFFSET_REF)
13486 ret = build_offset_ref_call_from_tree (function, &call_args);
13487 else if (TREE_CODE (function) == COMPONENT_REF)
13489 tree instance = TREE_OPERAND (function, 0);
13490 tree fn = TREE_OPERAND (function, 1);
13492 if (processing_template_decl
13493 && (type_dependent_expression_p (instance)
13494 || (!BASELINK_P (fn)
13495 && TREE_CODE (fn) != FIELD_DECL)
13496 || type_dependent_expression_p (fn)
13497 || any_type_dependent_arguments_p (call_args)))
13498 ret = build_nt_call_vec (function, call_args);
13499 else if (!BASELINK_P (fn))
13500 ret = finish_call_expr (function, &call_args,
13501 /*disallow_virtual=*/false,
13502 /*koenig_p=*/false,
13505 ret = (build_new_method_call
13507 &call_args, NULL_TREE,
13508 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13513 ret = finish_call_expr (function, &call_args,
13514 /*disallow_virtual=*/qualified_p,
13518 release_tree_vector (call_args);
13524 return build_x_conditional_expr
13525 (RECUR (TREE_OPERAND (t, 0)),
13526 RECUR (TREE_OPERAND (t, 1)),
13527 RECUR (TREE_OPERAND (t, 2)),
13530 case PSEUDO_DTOR_EXPR:
13531 return finish_pseudo_destructor_expr
13532 (RECUR (TREE_OPERAND (t, 0)),
13533 RECUR (TREE_OPERAND (t, 1)),
13534 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13538 tree purpose, value, chain;
13540 if (t == void_list_node)
13543 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13544 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13546 /* We have pack expansions, so expand those and
13547 create a new list out of it. */
13548 tree purposevec = NULL_TREE;
13549 tree valuevec = NULL_TREE;
13553 /* Expand the argument expressions. */
13554 if (TREE_PURPOSE (t))
13555 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13556 complain, in_decl);
13557 if (TREE_VALUE (t))
13558 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13559 complain, in_decl);
13561 /* Build the rest of the list. */
13562 chain = TREE_CHAIN (t);
13563 if (chain && chain != void_type_node)
13564 chain = RECUR (chain);
13566 /* Determine the number of arguments. */
13567 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13569 len = TREE_VEC_LENGTH (purposevec);
13570 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13572 else if (TREE_CODE (valuevec) == TREE_VEC)
13573 len = TREE_VEC_LENGTH (valuevec);
13576 /* Since we only performed a partial substitution into
13577 the argument pack, we only return a single list
13579 if (purposevec == TREE_PURPOSE (t)
13580 && valuevec == TREE_VALUE (t)
13581 && chain == TREE_CHAIN (t))
13584 return tree_cons (purposevec, valuevec, chain);
13587 /* Convert the argument vectors into a TREE_LIST */
13591 /* Grab the Ith values. */
13593 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13596 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13599 /* Build the list (backwards). */
13600 chain = tree_cons (purpose, value, chain);
13606 purpose = TREE_PURPOSE (t);
13608 purpose = RECUR (purpose);
13609 value = TREE_VALUE (t);
13611 value = RECUR (value);
13612 chain = TREE_CHAIN (t);
13613 if (chain && chain != void_type_node)
13614 chain = RECUR (chain);
13615 if (purpose == TREE_PURPOSE (t)
13616 && value == TREE_VALUE (t)
13617 && chain == TREE_CHAIN (t))
13619 return tree_cons (purpose, value, chain);
13622 case COMPONENT_REF:
13628 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13629 args, complain, in_decl);
13630 /* Remember that there was a reference to this entity. */
13631 if (DECL_P (object))
13632 mark_used (object);
13633 object_type = TREE_TYPE (object);
13635 member = TREE_OPERAND (t, 1);
13636 if (BASELINK_P (member))
13637 member = tsubst_baselink (member,
13638 non_reference (TREE_TYPE (object)),
13639 args, complain, in_decl);
13641 member = tsubst_copy (member, args, complain, in_decl);
13642 if (member == error_mark_node)
13643 return error_mark_node;
13645 if (object_type && !CLASS_TYPE_P (object_type))
13647 if (SCALAR_TYPE_P (object_type))
13649 tree s = NULL_TREE;
13650 tree dtor = member;
13652 if (TREE_CODE (dtor) == SCOPE_REF)
13654 s = TREE_OPERAND (dtor, 0);
13655 dtor = TREE_OPERAND (dtor, 1);
13657 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13659 dtor = TREE_OPERAND (dtor, 0);
13661 return finish_pseudo_destructor_expr (object, s, dtor);
13665 else if (TREE_CODE (member) == SCOPE_REF
13666 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13671 /* Lookup the template functions now that we know what the
13673 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13674 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13675 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13676 /*is_type_p=*/false,
13677 /*complain=*/false);
13678 if (BASELINK_P (member))
13680 BASELINK_FUNCTIONS (member)
13681 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13683 member = (adjust_result_of_qualified_name_lookup
13684 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13689 qualified_name_lookup_error (object_type, tmpl, member,
13691 return error_mark_node;
13694 else if (TREE_CODE (member) == SCOPE_REF
13695 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13696 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13698 if (complain & tf_error)
13700 if (TYPE_P (TREE_OPERAND (member, 0)))
13701 error ("%qT is not a class or namespace",
13702 TREE_OPERAND (member, 0));
13704 error ("%qD is not a class or namespace",
13705 TREE_OPERAND (member, 0));
13707 return error_mark_node;
13709 else if (TREE_CODE (member) == FIELD_DECL)
13710 return finish_non_static_data_member (member, object, NULL_TREE);
13712 return finish_class_member_access_expr (object, member,
13713 /*template_p=*/false,
13719 (RECUR (TREE_OPERAND (t, 0)));
13723 VEC(constructor_elt,gc) *n;
13724 constructor_elt *ce;
13725 unsigned HOST_WIDE_INT idx;
13726 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13727 bool process_index_p;
13729 bool need_copy_p = false;
13732 if (type == error_mark_node)
13733 return error_mark_node;
13735 /* digest_init will do the wrong thing if we let it. */
13736 if (type && TYPE_PTRMEMFUNC_P (type))
13739 /* We do not want to process the index of aggregate
13740 initializers as they are identifier nodes which will be
13741 looked up by digest_init. */
13742 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13744 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13745 newlen = VEC_length (constructor_elt, n);
13746 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13748 if (ce->index && process_index_p)
13749 ce->index = RECUR (ce->index);
13751 if (PACK_EXPANSION_P (ce->value))
13753 /* Substitute into the pack expansion. */
13754 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13757 if (ce->value == error_mark_node
13758 || PACK_EXPANSION_P (ce->value))
13760 else if (TREE_VEC_LENGTH (ce->value) == 1)
13761 /* Just move the argument into place. */
13762 ce->value = TREE_VEC_ELT (ce->value, 0);
13765 /* Update the length of the final CONSTRUCTOR
13766 arguments vector, and note that we will need to
13768 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13769 need_copy_p = true;
13773 ce->value = RECUR (ce->value);
13778 VEC(constructor_elt,gc) *old_n = n;
13780 n = VEC_alloc (constructor_elt, gc, newlen);
13781 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13783 if (TREE_CODE (ce->value) == TREE_VEC)
13785 int i, len = TREE_VEC_LENGTH (ce->value);
13786 for (i = 0; i < len; ++i)
13787 CONSTRUCTOR_APPEND_ELT (n, 0,
13788 TREE_VEC_ELT (ce->value, i));
13791 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13795 r = build_constructor (init_list_type_node, n);
13796 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13798 if (TREE_HAS_CONSTRUCTOR (t))
13799 return finish_compound_literal (type, r, complain);
13801 TREE_TYPE (r) = type;
13807 tree operand_0 = TREE_OPERAND (t, 0);
13808 if (TYPE_P (operand_0))
13810 operand_0 = tsubst (operand_0, args, complain, in_decl);
13811 return get_typeid (operand_0);
13815 operand_0 = RECUR (operand_0);
13816 return build_typeid (operand_0);
13827 tree r = tsubst_copy (t, args, complain, in_decl);
13829 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13830 /* If the original type was a reference, we'll be wrapped in
13831 the appropriate INDIRECT_REF. */
13832 r = convert_from_reference (r);
13837 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13838 tsubst (TREE_TYPE (t), args, complain, in_decl));
13840 case OFFSETOF_EXPR:
13841 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13845 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13846 complain, in_decl);
13848 tree type2 = TRAIT_EXPR_TYPE2 (t);
13850 type2 = tsubst_copy (type2, args, complain, in_decl);
13852 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13857 tree old_stmt_expr = cur_stmt_expr;
13858 tree stmt_expr = begin_stmt_expr ();
13860 cur_stmt_expr = stmt_expr;
13861 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13862 integral_constant_expression_p);
13863 stmt_expr = finish_stmt_expr (stmt_expr, false);
13864 cur_stmt_expr = old_stmt_expr;
13866 /* If the resulting list of expression statement is empty,
13867 fold it further into void_zero_node. */
13868 if (empty_expr_stmt_p (stmt_expr))
13869 stmt_expr = void_zero_node;
13875 t = tsubst_copy (t, args, complain, in_decl);
13876 /* As in finish_id_expression, we resolve enumeration constants
13877 to their underlying values. */
13878 if (TREE_CODE (t) == CONST_DECL)
13880 used_types_insert (TREE_TYPE (t));
13881 return DECL_INITIAL (t);
13887 tree r = build_lambda_expr ();
13889 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13890 TREE_TYPE (r) = type;
13891 CLASSTYPE_LAMBDA_EXPR (type) = r;
13893 LAMBDA_EXPR_LOCATION (r)
13894 = LAMBDA_EXPR_LOCATION (t);
13895 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13896 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13897 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13898 LAMBDA_EXPR_DISCRIMINATOR (r)
13899 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13900 LAMBDA_EXPR_EXTRA_SCOPE (r)
13901 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13902 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
13904 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
13905 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
13908 LAMBDA_EXPR_RETURN_TYPE (r)
13909 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13911 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
13912 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
13914 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13915 determine_visibility (TYPE_NAME (type));
13916 /* Now that we know visibility, instantiate the type so we have a
13917 declaration of the op() for later calls to lambda_function. */
13918 complete_type (type);
13920 /* The capture list refers to closure members, so this needs to
13921 wait until after we finish instantiating the type. */
13922 LAMBDA_EXPR_CAPTURE_LIST (r)
13923 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
13925 return build_lambda_object (r);
13929 /* We can get here for a constant initializer of non-dependent type.
13930 FIXME stop folding in cp_parser_initializer_clause. */
13931 gcc_assert (TREE_CONSTANT (t));
13933 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
13934 TREE_CONSTANT (r) = true;
13939 /* Handle Objective-C++ constructs, if appropriate. */
13942 = objcp_tsubst_copy_and_build (t, args, complain,
13943 in_decl, /*function_p=*/false);
13947 return tsubst_copy (t, args, complain, in_decl);
13953 /* Verify that the instantiated ARGS are valid. For type arguments,
13954 make sure that the type's linkage is ok. For non-type arguments,
13955 make sure they are constants if they are integral or enumerations.
13956 Emit an error under control of COMPLAIN, and return TRUE on error. */
13959 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
13961 if (ARGUMENT_PACK_P (t))
13963 tree vec = ARGUMENT_PACK_ARGS (t);
13964 int len = TREE_VEC_LENGTH (vec);
13965 bool result = false;
13968 for (i = 0; i < len; ++i)
13969 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
13973 else if (TYPE_P (t))
13975 /* [basic.link]: A name with no linkage (notably, the name
13976 of a class or enumeration declared in a local scope)
13977 shall not be used to declare an entity with linkage.
13978 This implies that names with no linkage cannot be used as
13981 DR 757 relaxes this restriction for C++0x. */
13982 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
13983 : no_linkage_check (t, /*relaxed_p=*/false));
13987 /* DR 488 makes use of a type with no linkage cause
13988 type deduction to fail. */
13989 if (complain & tf_error)
13991 if (TYPE_ANONYMOUS_P (nt))
13992 error ("%qT is/uses anonymous type", t);
13994 error ("template argument for %qD uses local type %qT",
13999 /* In order to avoid all sorts of complications, we do not
14000 allow variably-modified types as template arguments. */
14001 else if (variably_modified_type_p (t, NULL_TREE))
14003 if (complain & tf_error)
14004 error ("%qT is a variably modified type", t);
14008 /* A non-type argument of integral or enumerated type must be a
14010 else if (TREE_TYPE (t)
14011 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14012 && !TREE_CONSTANT (t))
14014 if (complain & tf_error)
14015 error ("integral expression %qE is not constant", t);
14022 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14024 int ix, len = DECL_NTPARMS (tmpl);
14025 bool result = false;
14027 for (ix = 0; ix != len; ix++)
14029 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14032 if (result && (complain & tf_error))
14033 error (" trying to instantiate %qD", tmpl);
14037 /* In C++0x, it's possible to have a function template whose type depends
14038 on itself recursively. This is most obvious with decltype, but can also
14039 occur with enumeration scope (c++/48969). So we need to catch infinite
14040 recursion and reject the substitution at deduction time; this function
14041 will return error_mark_node for any repeated substitution.
14043 This also catches excessive recursion such as when f<N> depends on
14044 f<N-1> across all integers, and returns error_mark_node for all the
14045 substitutions back up to the initial one.
14047 This is, of course, not reentrant. */
14050 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14052 static bool excessive_deduction_depth;
14053 static int deduction_depth;
14054 struct pending_template *old_last_pend = last_pending_template;
14055 struct tinst_level *old_error_tinst = last_error_tinst_level;
14057 tree fntype = TREE_TYPE (fn);
14061 if (excessive_deduction_depth)
14062 return error_mark_node;
14064 tinst = build_tree_list (fn, targs);
14065 if (!push_tinst_level (tinst))
14067 excessive_deduction_depth = true;
14069 return error_mark_node;
14072 input_location = DECL_SOURCE_LOCATION (fn);
14074 push_deduction_access_scope (fn);
14075 r = tsubst (fntype, targs, complain, NULL_TREE);
14076 pop_deduction_access_scope (fn);
14079 if (excessive_deduction_depth)
14081 r = error_mark_node;
14082 if (deduction_depth == 0)
14083 /* Reset once we're all the way out. */
14084 excessive_deduction_depth = false;
14087 pop_tinst_level ();
14088 /* We can't free this if a pending_template entry or last_error_tinst_level
14089 is pointing at it. */
14090 if (last_pending_template == old_last_pend
14091 && last_error_tinst_level == old_error_tinst)
14096 /* Instantiate the indicated variable or function template TMPL with
14097 the template arguments in TARG_PTR. */
14100 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14102 tree targ_ptr = orig_args;
14106 HOST_WIDE_INT saved_processing_template_decl;
14108 if (tmpl == error_mark_node)
14109 return error_mark_node;
14111 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14113 /* If this function is a clone, handle it specially. */
14114 if (DECL_CLONED_FUNCTION_P (tmpl))
14119 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14120 DECL_CLONED_FUNCTION. */
14121 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14122 targ_ptr, complain);
14123 if (spec == error_mark_node)
14124 return error_mark_node;
14126 /* Look for the clone. */
14127 FOR_EACH_CLONE (clone, spec)
14128 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14130 /* We should always have found the clone by now. */
14131 gcc_unreachable ();
14135 /* Check to see if we already have this specialization. */
14136 gen_tmpl = most_general_template (tmpl);
14137 if (tmpl != gen_tmpl)
14138 /* The TMPL is a partial instantiation. To get a full set of
14139 arguments we must add the arguments used to perform the
14140 partial instantiation. */
14141 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14144 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14145 but it doesn't seem to be on the hot path. */
14146 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14148 gcc_assert (tmpl == gen_tmpl
14149 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14151 || fndecl == NULL_TREE);
14153 if (spec != NULL_TREE)
14156 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14158 return error_mark_node;
14160 /* We are building a FUNCTION_DECL, during which the access of its
14161 parameters and return types have to be checked. However this
14162 FUNCTION_DECL which is the desired context for access checking
14163 is not built yet. We solve this chicken-and-egg problem by
14164 deferring all checks until we have the FUNCTION_DECL. */
14165 push_deferring_access_checks (dk_deferred);
14167 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
14168 (because, for example, we have encountered a non-dependent
14169 function call in the body of a template function and must now
14170 determine which of several overloaded functions will be called),
14171 within the instantiation itself we are not processing a
14173 saved_processing_template_decl = processing_template_decl;
14174 processing_template_decl = 0;
14175 /* Substitute template parameters to obtain the specialization. */
14176 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14177 targ_ptr, complain, gen_tmpl);
14178 processing_template_decl = saved_processing_template_decl;
14179 if (fndecl == error_mark_node)
14180 return error_mark_node;
14182 /* Now we know the specialization, compute access previously
14184 push_access_scope (fndecl);
14186 /* Some typedefs referenced from within the template code need to be access
14187 checked at template instantiation time, i.e now. These types were
14188 added to the template at parsing time. Let's get those and perfom
14189 the acces checks then. */
14190 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14191 perform_deferred_access_checks ();
14192 pop_access_scope (fndecl);
14193 pop_deferring_access_checks ();
14195 /* The DECL_TI_TEMPLATE should always be the immediate parent
14196 template, not the most general template. */
14197 DECL_TI_TEMPLATE (fndecl) = tmpl;
14199 /* If we've just instantiated the main entry point for a function,
14200 instantiate all the alternate entry points as well. We do this
14201 by cloning the instantiation of the main entry point, not by
14202 instantiating the template clones. */
14203 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14204 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14209 /* Wrapper for instantiate_template_1. */
14212 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14215 timevar_push (TV_TEMPLATE_INST);
14216 ret = instantiate_template_1 (tmpl, orig_args, complain);
14217 timevar_pop (TV_TEMPLATE_INST);
14221 /* We're going to do deduction substitution on the type of TMPL, a function
14222 template. In C++11 mode, push into that access scope. In C++03 mode,
14223 disable access checking. */
14226 push_deduction_access_scope (tree tmpl)
14228 if (cxx_dialect >= cxx0x)
14230 int ptd = processing_template_decl;
14231 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14232 /* Preserve processing_template_decl across push_to_top_level. */
14233 if (ptd && !processing_template_decl)
14234 ++processing_template_decl;
14237 push_deferring_access_checks (dk_no_check);
14240 /* And pop back out. */
14243 pop_deduction_access_scope (tree tmpl)
14245 if (cxx_dialect >= cxx0x)
14246 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14248 pop_deferring_access_checks ();
14251 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14252 NARGS elements of the arguments that are being used when calling
14253 it. TARGS is a vector into which the deduced template arguments
14256 Return zero for success, 2 for an incomplete match that doesn't resolve
14257 all the types, and 1 for complete failure. An error message will be
14258 printed only for an incomplete match.
14260 If FN is a conversion operator, or we are trying to produce a specific
14261 specialization, RETURN_TYPE is the return type desired.
14263 The EXPLICIT_TARGS are explicit template arguments provided via a
14266 The parameter STRICT is one of:
14269 We are deducing arguments for a function call, as in
14270 [temp.deduct.call].
14273 We are deducing arguments for a conversion function, as in
14274 [temp.deduct.conv].
14277 We are deducing arguments when doing an explicit instantiation
14278 as in [temp.explicit], when determining an explicit specialization
14279 as in [temp.expl.spec], or when taking the address of a function
14280 template, as in [temp.deduct.funcaddr]. */
14283 fn_type_unification (tree fn,
14284 tree explicit_targs,
14287 unsigned int nargs,
14289 unification_kind_t strict,
14296 bool incomplete_argument_packs_p = false;
14298 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14300 fntype = TREE_TYPE (fn);
14301 if (explicit_targs)
14305 The specified template arguments must match the template
14306 parameters in kind (i.e., type, nontype, template), and there
14307 must not be more arguments than there are parameters;
14308 otherwise type deduction fails.
14310 Nontype arguments must match the types of the corresponding
14311 nontype template parameters, or must be convertible to the
14312 types of the corresponding nontype parameters as specified in
14313 _temp.arg.nontype_, otherwise type deduction fails.
14315 All references in the function type of the function template
14316 to the corresponding template parameters are replaced by the
14317 specified template argument values. If a substitution in a
14318 template parameter or in the function type of the function
14319 template results in an invalid type, type deduction fails. */
14320 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14321 int i, len = TREE_VEC_LENGTH (tparms);
14322 tree converted_args;
14323 bool incomplete = false;
14325 if (explicit_targs == error_mark_node)
14326 return unify_invalid (explain_p);
14329 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14331 ? tf_warning_or_error
14333 /*require_all_args=*/false,
14334 /*use_default_args=*/false));
14335 if (converted_args == error_mark_node)
14338 /* Substitute the explicit args into the function type. This is
14339 necessary so that, for instance, explicitly declared function
14340 arguments can match null pointed constants. If we were given
14341 an incomplete set of explicit args, we must not do semantic
14342 processing during substitution as we could create partial
14344 for (i = 0; i < len; i++)
14346 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14347 bool parameter_pack = false;
14349 /* Dig out the actual parm. */
14350 if (TREE_CODE (parm) == TYPE_DECL
14351 || TREE_CODE (parm) == TEMPLATE_DECL)
14353 parm = TREE_TYPE (parm);
14354 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14356 else if (TREE_CODE (parm) == PARM_DECL)
14358 parm = DECL_INITIAL (parm);
14359 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14362 if (parameter_pack)
14366 template_parm_level_and_index (parm, &level, &idx);
14368 /* Mark the argument pack as "incomplete". We could
14369 still deduce more arguments during unification.
14370 We remove this mark in type_unification_real. */
14371 targ = TMPL_ARG (converted_args, level, idx);
14374 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14375 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14376 = ARGUMENT_PACK_ARGS (targ);
14379 /* We have some incomplete argument packs. */
14380 incomplete_argument_packs_p = true;
14384 if (incomplete_argument_packs_p)
14385 /* Any substitution is guaranteed to be incomplete if there
14386 are incomplete argument packs, because we can still deduce
14390 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
14392 processing_template_decl += incomplete;
14393 fntype = deduction_tsubst_fntype (fn, converted_args,
14395 ? tf_warning_or_error
14397 processing_template_decl -= incomplete;
14399 if (fntype == error_mark_node)
14402 /* Place the explicitly specified arguments in TARGS. */
14403 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14404 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14407 /* Never do unification on the 'this' parameter. */
14408 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14414 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14415 new_args = XALLOCAVEC (tree, nargs + 1);
14416 new_args[0] = return_type;
14417 memcpy (new_args + 1, args, nargs * sizeof (tree));
14422 /* We allow incomplete unification without an error message here
14423 because the standard doesn't seem to explicitly prohibit it. Our
14424 callers must be ready to deal with unification failures in any
14426 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14427 targs, parms, args, nargs, /*subr=*/0,
14428 strict, flags, explain_p);
14430 /* Now that we have bindings for all of the template arguments,
14431 ensure that the arguments deduced for the template template
14432 parameters have compatible template parameter lists. We cannot
14433 check this property before we have deduced all template
14434 arguments, because the template parameter types of a template
14435 template parameter might depend on prior template parameters
14436 deduced after the template template parameter. The following
14437 ill-formed example illustrates this issue:
14439 template<typename T, template<T> class C> void f(C<5>, T);
14441 template<int N> struct X {};
14444 f(X<5>(), 5l); // error: template argument deduction fails
14447 The template parameter list of 'C' depends on the template type
14448 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14449 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14450 time that we deduce 'C'. */
14452 && !template_template_parm_bindings_ok_p
14453 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14454 return unify_inconsistent_template_template_parameters (explain_p);
14457 /* All is well so far. Now, check:
14461 When all template arguments have been deduced, all uses of
14462 template parameters in nondeduced contexts are replaced with
14463 the corresponding deduced argument values. If the
14464 substitution results in an invalid type, as described above,
14465 type deduction fails. */
14467 tree substed = deduction_tsubst_fntype (fn, targs,
14469 ? tf_warning_or_error
14471 if (substed == error_mark_node)
14474 /* If we're looking for an exact match, check that what we got
14475 is indeed an exact match. It might not be if some template
14476 parameters are used in non-deduced contexts. */
14477 if (strict == DEDUCE_EXACT)
14482 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14484 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14485 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14486 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14487 return unify_type_mismatch (explain_p, args[i],
14488 TREE_VALUE (sarg));
14495 /* Adjust types before performing type deduction, as described in
14496 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14497 sections are symmetric. PARM is the type of a function parameter
14498 or the return type of the conversion function. ARG is the type of
14499 the argument passed to the call, or the type of the value
14500 initialized with the result of the conversion function.
14501 ARG_EXPR is the original argument expression, which may be null. */
14504 maybe_adjust_types_for_deduction (unification_kind_t strict,
14518 /* Swap PARM and ARG throughout the remainder of this
14519 function; the handling is precisely symmetric since PARM
14520 will initialize ARG rather than vice versa. */
14528 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14529 too, but here handle it by stripping the reference from PARM
14530 rather than by adding it to ARG. */
14531 if (TREE_CODE (*parm) == REFERENCE_TYPE
14532 && TYPE_REF_IS_RVALUE (*parm)
14533 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14534 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14535 && TREE_CODE (*arg) == REFERENCE_TYPE
14536 && !TYPE_REF_IS_RVALUE (*arg))
14537 *parm = TREE_TYPE (*parm);
14538 /* Nothing else to do in this case. */
14542 gcc_unreachable ();
14545 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14547 /* [temp.deduct.call]
14549 If P is not a reference type:
14551 --If A is an array type, the pointer type produced by the
14552 array-to-pointer standard conversion (_conv.array_) is
14553 used in place of A for type deduction; otherwise,
14555 --If A is a function type, the pointer type produced by
14556 the function-to-pointer standard conversion
14557 (_conv.func_) is used in place of A for type deduction;
14560 --If A is a cv-qualified type, the top level
14561 cv-qualifiers of A's type are ignored for type
14563 if (TREE_CODE (*arg) == ARRAY_TYPE)
14564 *arg = build_pointer_type (TREE_TYPE (*arg));
14565 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14566 *arg = build_pointer_type (*arg);
14568 *arg = TYPE_MAIN_VARIANT (*arg);
14571 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14572 of the form T&&, where T is a template parameter, and the argument
14573 is an lvalue, T is deduced as A& */
14574 if (TREE_CODE (*parm) == REFERENCE_TYPE
14575 && TYPE_REF_IS_RVALUE (*parm)
14576 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14577 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14578 && (arg_expr ? real_lvalue_p (arg_expr)
14579 /* try_one_overload doesn't provide an arg_expr, but
14580 functions are always lvalues. */
14581 : TREE_CODE (*arg) == FUNCTION_TYPE))
14582 *arg = build_reference_type (*arg);
14584 /* [temp.deduct.call]
14586 If P is a cv-qualified type, the top level cv-qualifiers
14587 of P's type are ignored for type deduction. If P is a
14588 reference type, the type referred to by P is used for
14590 *parm = TYPE_MAIN_VARIANT (*parm);
14591 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14593 *parm = TREE_TYPE (*parm);
14594 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14597 /* DR 322. For conversion deduction, remove a reference type on parm
14598 too (which has been swapped into ARG). */
14599 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14600 *arg = TREE_TYPE (*arg);
14605 /* Most parms like fn_type_unification.
14607 If SUBR is 1, we're being called recursively (to unify the
14608 arguments of a function or method parameter of a function
14612 type_unification_real (tree tparms,
14616 unsigned int xnargs,
14618 unification_kind_t strict,
14622 tree parm, arg, arg_expr;
14624 int ntparms = TREE_VEC_LENGTH (tparms);
14626 int saw_undeduced = 0;
14629 unsigned int nargs;
14632 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14633 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14634 gcc_assert (ntparms > 0);
14636 /* Reset the number of non-defaulted template arguments contained
14638 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14643 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
14644 | UNIFY_ALLOW_DERIVED);
14648 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14652 sub_strict = UNIFY_ALLOW_NONE;
14656 gcc_unreachable ();
14665 while (parms && parms != void_list_node
14668 parm = TREE_VALUE (parms);
14670 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
14671 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
14672 /* For a function parameter pack that occurs at the end of the
14673 parameter-declaration-list, the type A of each remaining
14674 argument of the call is compared with the type P of the
14675 declarator-id of the function parameter pack. */
14678 parms = TREE_CHAIN (parms);
14680 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
14681 /* For a function parameter pack that does not occur at the
14682 end of the parameter-declaration-list, the type of the
14683 parameter pack is a non-deduced context. */
14690 if (arg == error_mark_node)
14691 return unify_invalid (explain_p);
14692 if (arg == unknown_type_node)
14693 /* We can't deduce anything from this, but we might get all the
14694 template args from other function args. */
14697 /* Conversions will be performed on a function argument that
14698 corresponds with a function parameter that contains only
14699 non-deducible template parameters and explicitly specified
14700 template parameters. */
14701 if (!uses_template_parms (parm))
14706 type = TREE_TYPE (arg);
14710 if (same_type_p (parm, type))
14712 if (strict != DEDUCE_EXACT
14713 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
14717 if (strict == DEDUCE_EXACT)
14718 return unify_type_mismatch (explain_p, parm, arg);
14720 return unify_arg_conversion (explain_p, parm, type, arg);
14725 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14726 if (type_unknown_p (arg))
14728 /* [temp.deduct.type]
14730 A template-argument can be deduced from a pointer to
14731 function or pointer to member function argument if
14732 the set of overloaded functions does not contain
14733 function templates and at most one of a set of
14734 overloaded functions provides a unique match. */
14735 if (resolve_overloaded_unification
14736 (tparms, targs, parm, arg, strict, sub_strict, explain_p))
14739 return unify_overload_resolution_failure (explain_p, arg);
14742 arg = unlowered_expr_type (arg);
14743 if (arg == error_mark_node)
14744 return unify_invalid (explain_p);
14748 int arg_strict = sub_strict;
14751 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
14754 if (arg == init_list_type_node && arg_expr)
14756 if (unify (tparms, targs, parm, arg, arg_strict, explain_p))
14757 /* If unification failed, the recursive call will have updated
14758 UI appropriately. */
14765 && parms != void_list_node
14766 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14768 /* Unify the remaining arguments with the pack expansion type. */
14770 tree parmvec = make_tree_vec (1);
14772 /* Allocate a TREE_VEC and copy in all of the arguments */
14773 argvec = make_tree_vec (nargs - ia);
14774 for (i = 0; ia < nargs; ++ia, ++i)
14775 TREE_VEC_ELT (argvec, i) = args[ia];
14777 /* Copy the parameter into parmvec. */
14778 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14779 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14780 /*call_args_p=*/true, /*subr=*/subr, explain_p))
14783 /* Advance to the end of the list of parameters. */
14784 parms = TREE_CHAIN (parms);
14787 /* Fail if we've reached the end of the parm list, and more args
14788 are present, and the parm list isn't variadic. */
14789 if (ia < nargs && parms == void_list_node)
14790 return unify_too_many_arguments (explain_p, nargs, ia);
14791 /* Fail if parms are left and they don't have default values. */
14792 if (parms && parms != void_list_node
14793 && TREE_PURPOSE (parms) == NULL_TREE)
14795 unsigned int count = nargs;
14797 while (p && p != void_list_node)
14800 p = TREE_CHAIN (p);
14802 return unify_too_few_arguments (explain_p, ia, count);
14807 /* Check to see if we need another pass before we start clearing
14808 ARGUMENT_PACK_INCOMPLETE_P. */
14809 for (i = 0; i < ntparms; i++)
14811 tree targ = TREE_VEC_ELT (targs, i);
14812 tree tparm = TREE_VEC_ELT (tparms, i);
14814 if (targ || tparm == error_mark_node)
14816 tparm = TREE_VALUE (tparm);
14818 /* If this is an undeduced nontype parameter that depends on
14819 a type parameter, try another pass; its type may have been
14820 deduced from a later argument than the one from which
14821 this parameter can be deduced. */
14822 if (TREE_CODE (tparm) == PARM_DECL
14823 && uses_template_parms (TREE_TYPE (tparm))
14824 && !saw_undeduced++)
14828 for (i = 0; i < ntparms; i++)
14830 tree targ = TREE_VEC_ELT (targs, i);
14831 tree tparm = TREE_VEC_ELT (tparms, i);
14833 /* Clear the "incomplete" flags on all argument packs now so that
14834 substituting them into later default arguments works. */
14835 if (targ && ARGUMENT_PACK_P (targ))
14837 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14838 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14841 if (targ || tparm == error_mark_node)
14843 tparm = TREE_VALUE (tparm);
14845 /* Core issue #226 (C++0x) [temp.deduct]:
14847 If a template argument has not been deduced, its
14848 default template argument, if any, is used.
14850 When we are in C++98 mode, TREE_PURPOSE will either
14851 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14852 to explicitly check cxx_dialect here. */
14853 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14855 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14856 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
14857 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
14858 arg = convert_template_argument (parm, arg, targs,
14860 ? tf_warning_or_error
14863 if (arg == error_mark_node)
14867 TREE_VEC_ELT (targs, i) = arg;
14868 /* The position of the first default template argument,
14869 is also the number of non-defaulted arguments in TARGS.
14871 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14872 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
14877 /* If the type parameter is a parameter pack, then it will
14878 be deduced to an empty parameter pack. */
14879 if (template_parameter_pack_p (tparm))
14883 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
14885 arg = make_node (NONTYPE_ARGUMENT_PACK);
14886 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
14887 TREE_CONSTANT (arg) = 1;
14890 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
14892 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
14894 TREE_VEC_ELT (targs, i) = arg;
14898 return unify_parameter_deduction_failure (explain_p, tparm);
14901 #ifdef ENABLE_CHECKING
14902 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
14903 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
14906 return unify_success (explain_p);
14909 /* Subroutine of type_unification_real. Args are like the variables
14910 at the call site. ARG is an overloaded function (or template-id);
14911 we try deducing template args from each of the overloads, and if
14912 only one succeeds, we go with that. Modifies TARGS and returns
14913 true on success. */
14916 resolve_overloaded_unification (tree tparms,
14920 unification_kind_t strict,
14924 tree tempargs = copy_node (targs);
14926 tree goodfn = NULL_TREE;
14929 if (TREE_CODE (arg) == ADDR_EXPR)
14931 arg = TREE_OPERAND (arg, 0);
14937 if (TREE_CODE (arg) == COMPONENT_REF)
14938 /* Handle `&x' where `x' is some static or non-static member
14940 arg = TREE_OPERAND (arg, 1);
14942 if (TREE_CODE (arg) == OFFSET_REF)
14943 arg = TREE_OPERAND (arg, 1);
14945 /* Strip baselink information. */
14946 if (BASELINK_P (arg))
14947 arg = BASELINK_FUNCTIONS (arg);
14949 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
14951 /* If we got some explicit template args, we need to plug them into
14952 the affected templates before we try to unify, in case the
14953 explicit args will completely resolve the templates in question. */
14956 tree expl_subargs = TREE_OPERAND (arg, 1);
14957 arg = TREE_OPERAND (arg, 0);
14959 for (; arg; arg = OVL_NEXT (arg))
14961 tree fn = OVL_CURRENT (arg);
14962 tree subargs, elem;
14964 if (TREE_CODE (fn) != TEMPLATE_DECL)
14967 ++processing_template_decl;
14968 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
14969 expl_subargs, /*check_ret=*/false);
14970 if (subargs && !any_dependent_template_arguments_p (subargs))
14972 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
14973 if (try_one_overload (tparms, targs, tempargs, parm,
14974 elem, strict, sub_strict, addr_p, explain_p)
14975 && (!goodfn || !decls_match (goodfn, elem)))
14983 --processing_template_decl;
14985 /* If no templates (or more than one) are fully resolved by the
14986 explicit arguments, this template-id is a non-deduced context; it
14987 could still be OK if we deduce all template arguments for the
14988 enclosing call through other arguments. */
14992 else if (TREE_CODE (arg) != OVERLOAD
14993 && TREE_CODE (arg) != FUNCTION_DECL)
14994 /* If ARG is, for example, "(0, &f)" then its type will be unknown
14995 -- but the deduction does not succeed because the expression is
14996 not just the function on its own. */
14999 for (; arg; arg = OVL_NEXT (arg))
15000 if (try_one_overload (tparms, targs, tempargs, parm,
15001 TREE_TYPE (OVL_CURRENT (arg)),
15002 strict, sub_strict, addr_p, explain_p)
15003 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15005 goodfn = OVL_CURRENT (arg);
15009 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15010 to function or pointer to member function argument if the set of
15011 overloaded functions does not contain function templates and at most
15012 one of a set of overloaded functions provides a unique match.
15014 So if we found multiple possibilities, we return success but don't
15015 deduce anything. */
15019 int i = TREE_VEC_LENGTH (targs);
15021 if (TREE_VEC_ELT (tempargs, i))
15022 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15030 /* Core DR 115: In contexts where deduction is done and fails, or in
15031 contexts where deduction is not done, if a template argument list is
15032 specified and it, along with any default template arguments, identifies
15033 a single function template specialization, then the template-id is an
15034 lvalue for the function template specialization. */
15037 resolve_nondeduced_context (tree orig_expr)
15039 tree expr, offset, baselink;
15042 if (!type_unknown_p (orig_expr))
15047 offset = NULL_TREE;
15048 baselink = NULL_TREE;
15050 if (TREE_CODE (expr) == ADDR_EXPR)
15052 expr = TREE_OPERAND (expr, 0);
15055 if (TREE_CODE (expr) == OFFSET_REF)
15058 expr = TREE_OPERAND (expr, 1);
15060 if (TREE_CODE (expr) == BASELINK)
15063 expr = BASELINK_FUNCTIONS (expr);
15066 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15069 tree goodfn = NULL_TREE;
15071 /* If we got some explicit template args, we need to plug them into
15072 the affected templates before we try to unify, in case the
15073 explicit args will completely resolve the templates in question. */
15075 tree expl_subargs = TREE_OPERAND (expr, 1);
15076 tree arg = TREE_OPERAND (expr, 0);
15077 tree badfn = NULL_TREE;
15078 tree badargs = NULL_TREE;
15080 for (; arg; arg = OVL_NEXT (arg))
15082 tree fn = OVL_CURRENT (arg);
15083 tree subargs, elem;
15085 if (TREE_CODE (fn) != TEMPLATE_DECL)
15088 ++processing_template_decl;
15089 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15090 expl_subargs, /*check_ret=*/false);
15091 if (subargs && !any_dependent_template_arguments_p (subargs))
15093 elem = instantiate_template (fn, subargs, tf_none);
15094 if (elem == error_mark_node)
15099 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15105 --processing_template_decl;
15109 mark_used (goodfn);
15112 expr = build_baselink (BASELINK_BINFO (baselink),
15113 BASELINK_ACCESS_BINFO (baselink),
15114 expr, BASELINK_OPTYPE (baselink));
15118 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15119 expr = build_offset_ref (base, expr, addr);
15122 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15125 else if (good == 0 && badargs)
15126 /* There were no good options and at least one bad one, so let the
15127 user know what the problem is. */
15128 instantiate_template (badfn, badargs, tf_warning_or_error);
15133 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15134 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15135 different overloads deduce different arguments for a given parm.
15136 ADDR_P is true if the expression for which deduction is being
15137 performed was of the form "& fn" rather than simply "fn".
15139 Returns 1 on success. */
15142 try_one_overload (tree tparms,
15147 unification_kind_t strict,
15156 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15157 to function or pointer to member function argument if the set of
15158 overloaded functions does not contain function templates and at most
15159 one of a set of overloaded functions provides a unique match.
15161 So if this is a template, just return success. */
15163 if (uses_template_parms (arg))
15166 if (TREE_CODE (arg) == METHOD_TYPE)
15167 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15169 arg = build_pointer_type (arg);
15171 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15173 /* We don't copy orig_targs for this because if we have already deduced
15174 some template args from previous args, unify would complain when we
15175 try to deduce a template parameter for the same argument, even though
15176 there isn't really a conflict. */
15177 nargs = TREE_VEC_LENGTH (targs);
15178 tempargs = make_tree_vec (nargs);
15180 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15183 /* First make sure we didn't deduce anything that conflicts with
15184 explicitly specified args. */
15185 for (i = nargs; i--; )
15187 tree elt = TREE_VEC_ELT (tempargs, i);
15188 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15192 else if (uses_template_parms (elt))
15193 /* Since we're unifying against ourselves, we will fill in
15194 template args used in the function parm list with our own
15195 template parms. Discard them. */
15196 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15197 else if (oldelt && !template_args_equal (oldelt, elt))
15201 for (i = nargs; i--; )
15203 tree elt = TREE_VEC_ELT (tempargs, i);
15206 TREE_VEC_ELT (targs, i) = elt;
15212 /* PARM is a template class (perhaps with unbound template
15213 parameters). ARG is a fully instantiated type. If ARG can be
15214 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15215 TARGS are as for unify. */
15218 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15221 tree copy_of_targs;
15223 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15224 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15225 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15228 /* We need to make a new template argument vector for the call to
15229 unify. If we used TARGS, we'd clutter it up with the result of
15230 the attempted unification, even if this class didn't work out.
15231 We also don't want to commit ourselves to all the unifications
15232 we've already done, since unification is supposed to be done on
15233 an argument-by-argument basis. In other words, consider the
15234 following pathological case:
15236 template <int I, int J, int K>
15239 template <int I, int J>
15240 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15242 template <int I, int J, int K>
15243 void f(S<I, J, K>, S<I, I, I>);
15252 Now, by the time we consider the unification involving `s2', we
15253 already know that we must have `f<0, 0, 0>'. But, even though
15254 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15255 because there are two ways to unify base classes of S<0, 1, 2>
15256 with S<I, I, I>. If we kept the already deduced knowledge, we
15257 would reject the possibility I=1. */
15258 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15260 /* If unification failed, we're done. */
15261 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15262 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15268 /* Given a template type PARM and a class type ARG, find the unique
15269 base type in ARG that is an instance of PARM. We do not examine
15270 ARG itself; only its base-classes. If there is not exactly one
15271 appropriate base class, return NULL_TREE. PARM may be the type of
15272 a partial specialization, as well as a plain template type. Used
15275 static enum template_base_result
15276 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15277 bool explain_p, tree *result)
15279 tree rval = NULL_TREE;
15282 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15284 binfo = TYPE_BINFO (complete_type (arg));
15287 /* The type could not be completed. */
15288 *result = NULL_TREE;
15289 return tbr_incomplete_type;
15292 /* Walk in inheritance graph order. The search order is not
15293 important, and this avoids multiple walks of virtual bases. */
15294 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15296 tree r = try_class_unification (tparms, targs, parm,
15297 BINFO_TYPE (binfo), explain_p);
15301 /* If there is more than one satisfactory baseclass, then:
15305 If they yield more than one possible deduced A, the type
15309 if (rval && !same_type_p (r, rval))
15311 *result = NULL_TREE;
15312 return tbr_ambiguous_baseclass;
15320 return tbr_success;
15323 /* Returns the level of DECL, which declares a template parameter. */
15326 template_decl_level (tree decl)
15328 switch (TREE_CODE (decl))
15331 case TEMPLATE_DECL:
15332 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15335 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15338 gcc_unreachable ();
15343 /* Decide whether ARG can be unified with PARM, considering only the
15344 cv-qualifiers of each type, given STRICT as documented for unify.
15345 Returns nonzero iff the unification is OK on that basis. */
15348 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15350 int arg_quals = cp_type_quals (arg);
15351 int parm_quals = cp_type_quals (parm);
15353 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15354 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15356 /* Although a CVR qualifier is ignored when being applied to a
15357 substituted template parameter ([8.3.2]/1 for example), that
15358 does not allow us to unify "const T" with "int&" because both
15359 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15360 It is ok when we're allowing additional CV qualifiers
15361 at the outer level [14.8.2.1]/3,1st bullet. */
15362 if ((TREE_CODE (arg) == REFERENCE_TYPE
15363 || TREE_CODE (arg) == FUNCTION_TYPE
15364 || TREE_CODE (arg) == METHOD_TYPE)
15365 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15368 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15369 && (parm_quals & TYPE_QUAL_RESTRICT))
15373 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15374 && (arg_quals & parm_quals) != parm_quals)
15377 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15378 && (parm_quals & arg_quals) != arg_quals)
15384 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15386 template_parm_level_and_index (tree parm, int* level, int* index)
15388 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15389 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15390 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15392 *index = TEMPLATE_TYPE_IDX (parm);
15393 *level = TEMPLATE_TYPE_LEVEL (parm);
15397 *index = TEMPLATE_PARM_IDX (parm);
15398 *level = TEMPLATE_PARM_LEVEL (parm);
15402 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15404 if (unify (TP, TA, P, A, S, EP)) \
15408 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15409 expansion at the end of PACKED_PARMS. Returns 0 if the type
15410 deduction succeeds, 1 otherwise. STRICT is the same as in
15411 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15412 call argument list. We'll need to adjust the arguments to make them
15413 types. SUBR tells us if this is from a recursive call to
15414 type_unification_real. */
15416 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15417 tree packed_args, int strict, bool call_args_p,
15418 bool subr, bool explain_p)
15421 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15422 tree pattern = PACK_EXPANSION_PATTERN (parm);
15423 tree pack, packs = NULL_TREE;
15424 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15425 int len = TREE_VEC_LENGTH (packed_args);
15427 /* Determine the parameter packs we will be deducing from the
15428 pattern, and record their current deductions. */
15429 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15430 pack; pack = TREE_CHAIN (pack))
15432 tree parm_pack = TREE_VALUE (pack);
15435 /* Determine the index and level of this parameter pack. */
15436 template_parm_level_and_index (parm_pack, &level, &idx);
15438 /* Keep track of the parameter packs and their corresponding
15440 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15441 TREE_TYPE (packs) = make_tree_vec (len - start);
15444 /* Loop through all of the arguments that have not yet been
15445 unified and unify each with the pattern. */
15446 for (i = start; i < len; i++)
15448 tree parm = pattern;
15450 /* For each parameter pack, clear out the deduced value so that
15451 we can deduce it again. */
15452 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15455 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15457 TMPL_ARG (targs, level, idx) = NULL_TREE;
15460 /* Unify the pattern with the current argument. */
15462 tree arg = TREE_VEC_ELT (packed_args, i);
15463 tree arg_expr = NULL_TREE;
15464 int arg_strict = strict;
15470 /* This mirrors what we do in type_unification_real. */
15474 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
15475 | UNIFY_ALLOW_MORE_CV_QUAL
15476 | UNIFY_ALLOW_DERIVED);
15480 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15484 sub_strict = UNIFY_ALLOW_NONE;
15488 gcc_unreachable ();
15493 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15494 if (type_unknown_p (arg))
15496 /* [temp.deduct.type] A template-argument can be
15497 deduced from a pointer to function or pointer
15498 to member function argument if the set of
15499 overloaded functions does not contain function
15500 templates and at most one of a set of
15501 overloaded functions provides a unique
15504 if (resolve_overloaded_unification
15505 (tparms, targs, parm, arg,
15506 (unification_kind_t) strict,
15507 sub_strict, explain_p))
15509 return unify_overload_resolution_failure (explain_p, arg);
15513 arg = unlowered_expr_type (arg);
15514 if (arg == error_mark_node)
15515 return unify_invalid (explain_p);
15518 arg_strict = sub_strict;
15522 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
15523 &parm, &arg, arg_expr);
15526 /* For deduction from an init-list we need the actual list. */
15527 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15529 RECUR_AND_CHECK_FAILURE (tparms, targs, parm, arg, arg_strict,
15534 /* For each parameter pack, collect the deduced value. */
15535 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15538 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15540 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15541 TMPL_ARG (targs, level, idx);
15545 /* Verify that the results of unification with the parameter packs
15546 produce results consistent with what we've seen before, and make
15547 the deduced argument packs available. */
15548 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15550 tree old_pack = TREE_VALUE (pack);
15551 tree new_args = TREE_TYPE (pack);
15552 int i, len = TREE_VEC_LENGTH (new_args);
15554 bool nondeduced_p = false;
15556 /* By default keep the original deduced argument pack.
15557 If necessary, more specific code is going to update the
15558 resulting deduced argument later down in this function. */
15559 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15560 TMPL_ARG (targs, level, idx) = old_pack;
15562 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15563 actually deduce anything. */
15564 for (i = 0; i < len && !nondeduced_p; ++i)
15565 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15566 nondeduced_p = true;
15570 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15572 /* Prepend the explicit arguments onto NEW_ARGS. */
15573 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15574 tree old_args = new_args;
15575 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
15576 int len = explicit_len + TREE_VEC_LENGTH (old_args);
15578 /* Copy the explicit arguments. */
15579 new_args = make_tree_vec (len);
15580 for (i = 0; i < explicit_len; i++)
15581 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
15583 /* Copy the deduced arguments. */
15584 for (; i < len; i++)
15585 TREE_VEC_ELT (new_args, i) =
15586 TREE_VEC_ELT (old_args, i - explicit_len);
15592 /* Build the deduced *_ARGUMENT_PACK. */
15593 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15595 result = make_node (NONTYPE_ARGUMENT_PACK);
15596 TREE_TYPE (result) =
15597 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15598 TREE_CONSTANT (result) = 1;
15601 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15603 SET_ARGUMENT_PACK_ARGS (result, new_args);
15605 /* Note the deduced argument packs for this parameter
15607 TMPL_ARG (targs, level, idx) = result;
15609 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15610 && (ARGUMENT_PACK_ARGS (old_pack)
15611 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15613 /* We only had the explicitly-provided arguments before, but
15614 now we have a complete set of arguments. */
15615 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15617 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15618 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15619 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15623 tree bad_old_arg, bad_new_arg;
15624 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
15626 if (!comp_template_args_with_info (old_args, new_args,
15627 &bad_old_arg, &bad_new_arg))
15628 /* Inconsistent unification of this parameter pack. */
15629 return unify_parameter_pack_inconsistent (explain_p,
15635 return unify_success (explain_p);
15638 /* Deduce the value of template parameters. TPARMS is the (innermost)
15639 set of template parameters to a template. TARGS is the bindings
15640 for those template parameters, as determined thus far; TARGS may
15641 include template arguments for outer levels of template parameters
15642 as well. PARM is a parameter to a template function, or a
15643 subcomponent of that parameter; ARG is the corresponding argument.
15644 This function attempts to match PARM with ARG in a manner
15645 consistent with the existing assignments in TARGS. If more values
15646 are deduced, then TARGS is updated.
15648 Returns 0 if the type deduction succeeds, 1 otherwise. The
15649 parameter STRICT is a bitwise or of the following flags:
15652 Require an exact match between PARM and ARG.
15653 UNIFY_ALLOW_MORE_CV_QUAL:
15654 Allow the deduced ARG to be more cv-qualified (by qualification
15655 conversion) than ARG.
15656 UNIFY_ALLOW_LESS_CV_QUAL:
15657 Allow the deduced ARG to be less cv-qualified than ARG.
15658 UNIFY_ALLOW_DERIVED:
15659 Allow the deduced ARG to be a template base class of ARG,
15660 or a pointer to a template base class of the type pointed to by
15662 UNIFY_ALLOW_INTEGER:
15663 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15664 case for more information.
15665 UNIFY_ALLOW_OUTER_LEVEL:
15666 This is the outermost level of a deduction. Used to determine validity
15667 of qualification conversions. A valid qualification conversion must
15668 have const qualified pointers leading up to the inner type which
15669 requires additional CV quals, except at the outer level, where const
15670 is not required [conv.qual]. It would be normal to set this flag in
15671 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15672 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15673 This is the outermost level of a deduction, and PARM can be more CV
15674 qualified at this point.
15675 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15676 This is the outermost level of a deduction, and PARM can be less CV
15677 qualified at this point. */
15680 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
15686 int strict_in = strict;
15688 /* I don't think this will do the right thing with respect to types.
15689 But the only case I've seen it in so far has been array bounds, where
15690 signedness is the only information lost, and I think that will be
15692 while (TREE_CODE (parm) == NOP_EXPR)
15693 parm = TREE_OPERAND (parm, 0);
15695 if (arg == error_mark_node)
15696 return unify_invalid (explain_p);
15697 if (arg == unknown_type_node
15698 || arg == init_list_type_node)
15699 /* We can't deduce anything from this, but we might get all the
15700 template args from other function args. */
15701 return unify_success (explain_p);
15703 /* If PARM uses template parameters, then we can't bail out here,
15704 even if ARG == PARM, since we won't record unifications for the
15705 template parameters. We might need them if we're trying to
15706 figure out which of two things is more specialized. */
15707 if (arg == parm && !uses_template_parms (parm))
15708 return unify_success (explain_p);
15710 /* Handle init lists early, so the rest of the function can assume
15711 we're dealing with a type. */
15712 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15716 tree orig_parm = parm;
15718 /* Replace T with std::initializer_list<T> for deduction. */
15719 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15720 && flag_deduce_init_list)
15721 parm = listify (parm);
15723 if (!is_std_init_list (parm))
15724 /* We can only deduce from an initializer list argument if the
15725 parameter is std::initializer_list; otherwise this is a
15726 non-deduced context. */
15727 return unify_success (explain_p);
15729 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15731 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15733 int elt_strict = strict;
15735 if (elt == error_mark_node)
15736 return unify_invalid (explain_p);
15738 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15740 tree type = TREE_TYPE (elt);
15741 /* It should only be possible to get here for a call. */
15742 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15743 elt_strict |= maybe_adjust_types_for_deduction
15744 (DEDUCE_CALL, &elttype, &type, elt);
15748 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
15752 /* If the std::initializer_list<T> deduction worked, replace the
15753 deduced A with std::initializer_list<A>. */
15754 if (orig_parm != parm)
15756 idx = TEMPLATE_TYPE_IDX (orig_parm);
15757 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15758 targ = listify (targ);
15759 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15761 return unify_success (explain_p);
15764 /* Immediately reject some pairs that won't unify because of
15765 cv-qualification mismatches. */
15766 if (TREE_CODE (arg) == TREE_CODE (parm)
15768 /* It is the elements of the array which hold the cv quals of an array
15769 type, and the elements might be template type parms. We'll check
15770 when we recurse. */
15771 && TREE_CODE (arg) != ARRAY_TYPE
15772 /* We check the cv-qualifiers when unifying with template type
15773 parameters below. We want to allow ARG `const T' to unify with
15774 PARM `T' for example, when computing which of two templates
15775 is more specialized, for example. */
15776 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15777 && !check_cv_quals_for_unify (strict_in, arg, parm))
15778 return unify_cv_qual_mismatch (explain_p, parm, arg);
15780 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15781 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15782 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15783 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15784 strict &= ~UNIFY_ALLOW_DERIVED;
15785 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15786 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15788 switch (TREE_CODE (parm))
15790 case TYPENAME_TYPE:
15792 case UNBOUND_CLASS_TEMPLATE:
15793 /* In a type which contains a nested-name-specifier, template
15794 argument values cannot be deduced for template parameters used
15795 within the nested-name-specifier. */
15796 return unify_success (explain_p);
15798 case TEMPLATE_TYPE_PARM:
15799 case TEMPLATE_TEMPLATE_PARM:
15800 case BOUND_TEMPLATE_TEMPLATE_PARM:
15801 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15802 if (tparm == error_mark_node)
15803 return unify_invalid (explain_p);
15805 if (TEMPLATE_TYPE_LEVEL (parm)
15806 != template_decl_level (tparm))
15807 /* The PARM is not one we're trying to unify. Just check
15808 to see if it matches ARG. */
15810 if (TREE_CODE (arg) == TREE_CODE (parm)
15811 && same_type_p (parm, arg))
15812 return unify_success (explain_p);
15814 return unify_type_mismatch (explain_p, parm, arg);
15816 idx = TEMPLATE_TYPE_IDX (parm);
15817 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15818 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15820 /* Check for mixed types and values. */
15821 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15822 && TREE_CODE (tparm) != TYPE_DECL)
15823 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15824 && TREE_CODE (tparm) != TEMPLATE_DECL))
15825 gcc_unreachable ();
15827 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15829 /* ARG must be constructed from a template class or a template
15830 template parameter. */
15831 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15832 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15833 return unify_template_deduction_failure (explain_p, parm, arg);
15836 tree parmvec = TYPE_TI_ARGS (parm);
15837 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15838 tree full_argvec = add_to_template_args (targs, argvec);
15840 = DECL_INNERMOST_TEMPLATE_PARMS
15841 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15843 int parm_variadic_p = 0;
15845 /* The resolution to DR150 makes clear that default
15846 arguments for an N-argument may not be used to bind T
15847 to a template template parameter with fewer than N
15848 parameters. It is not safe to permit the binding of
15849 default arguments as an extension, as that may change
15850 the meaning of a conforming program. Consider:
15852 struct Dense { static const unsigned int dim = 1; };
15854 template <template <typename> class View,
15856 void operator+(float, View<Block> const&);
15858 template <typename Block,
15859 unsigned int Dim = Block::dim>
15860 struct Lvalue_proxy { operator float() const; };
15864 Lvalue_proxy<Dense> p;
15869 Here, if Lvalue_proxy is permitted to bind to View, then
15870 the global operator+ will be used; if they are not, the
15871 Lvalue_proxy will be converted to float. */
15872 if (coerce_template_parms (parm_parms,
15874 TYPE_TI_TEMPLATE (parm),
15876 ? tf_warning_or_error
15878 /*require_all_args=*/true,
15879 /*use_default_args=*/false)
15880 == error_mark_node)
15883 /* Deduce arguments T, i from TT<T> or TT<i>.
15884 We check each element of PARMVEC and ARGVEC individually
15885 rather than the whole TREE_VEC since they can have
15886 different number of elements. */
15888 parmvec = expand_template_argument_pack (parmvec);
15889 argvec = expand_template_argument_pack (argvec);
15891 len = TREE_VEC_LENGTH (parmvec);
15893 /* Check if the parameters end in a pack, making them
15896 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15897 parm_variadic_p = 1;
15899 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15900 return unify_too_few_arguments (explain_p,
15901 TREE_VEC_LENGTH (argvec), len);
15903 for (i = 0; i < len - parm_variadic_p; ++i)
15905 RECUR_AND_CHECK_FAILURE (tparms, targs,
15906 TREE_VEC_ELT (parmvec, i),
15907 TREE_VEC_ELT (argvec, i),
15908 UNIFY_ALLOW_NONE, explain_p);
15911 if (parm_variadic_p
15912 && unify_pack_expansion (tparms, targs,
15915 /*call_args_p=*/false,
15916 /*subr=*/false, explain_p))
15919 arg = TYPE_TI_TEMPLATE (arg);
15921 /* Fall through to deduce template name. */
15924 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15925 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15927 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
15929 /* Simple cases: Value already set, does match or doesn't. */
15930 if (targ != NULL_TREE && template_args_equal (targ, arg))
15931 return unify_success (explain_p);
15933 return unify_inconsistency (explain_p, parm, targ, arg);
15937 /* If PARM is `const T' and ARG is only `int', we don't have
15938 a match unless we are allowing additional qualification.
15939 If ARG is `const int' and PARM is just `T' that's OK;
15940 that binds `const int' to `T'. */
15941 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
15943 return unify_cv_qual_mismatch (explain_p, parm, arg);
15945 /* Consider the case where ARG is `const volatile int' and
15946 PARM is `const T'. Then, T should be `volatile int'. */
15947 arg = cp_build_qualified_type_real
15948 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
15949 if (arg == error_mark_node)
15950 return unify_invalid (explain_p);
15952 /* Simple cases: Value already set, does match or doesn't. */
15953 if (targ != NULL_TREE && same_type_p (targ, arg))
15954 return unify_success (explain_p);
15956 return unify_inconsistency (explain_p, parm, targ, arg);
15958 /* Make sure that ARG is not a variable-sized array. (Note
15959 that were talking about variable-sized arrays (like
15960 `int[n]'), rather than arrays of unknown size (like
15961 `int[]').) We'll get very confused by such a type since
15962 the bound of the array is not constant, and therefore
15963 not mangleable. Besides, such types are not allowed in
15964 ISO C++, so we can do as we please here. We do allow
15965 them for 'auto' deduction, since that isn't ABI-exposed. */
15966 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
15967 return unify_vla_arg (explain_p, arg);
15969 /* Strip typedefs as in convert_template_argument. */
15970 arg = canonicalize_type_argument (arg, tf_none);
15973 /* If ARG is a parameter pack or an expansion, we cannot unify
15974 against it unless PARM is also a parameter pack. */
15975 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
15976 && !template_parameter_pack_p (parm))
15977 return unify_parameter_pack_mismatch (explain_p, parm, arg);
15979 /* If the argument deduction results is a METHOD_TYPE,
15980 then there is a problem.
15981 METHOD_TYPE doesn't map to any real C++ type the result of
15982 the deduction can not be of that type. */
15983 if (TREE_CODE (arg) == METHOD_TYPE)
15984 return unify_method_type_error (explain_p, arg);
15986 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
15987 return unify_success (explain_p);
15989 case TEMPLATE_PARM_INDEX:
15990 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15991 if (tparm == error_mark_node)
15992 return unify_invalid (explain_p);
15994 if (TEMPLATE_PARM_LEVEL (parm)
15995 != template_decl_level (tparm))
15997 /* The PARM is not one we're trying to unify. Just check
15998 to see if it matches ARG. */
15999 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16000 && cp_tree_equal (parm, arg));
16002 unify_expression_unequal (explain_p, parm, arg);
16006 idx = TEMPLATE_PARM_IDX (parm);
16007 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16011 int x = !cp_tree_equal (targ, arg);
16013 unify_inconsistency (explain_p, parm, targ, arg);
16017 /* [temp.deduct.type] If, in the declaration of a function template
16018 with a non-type template-parameter, the non-type
16019 template-parameter is used in an expression in the function
16020 parameter-list and, if the corresponding template-argument is
16021 deduced, the template-argument type shall match the type of the
16022 template-parameter exactly, except that a template-argument
16023 deduced from an array bound may be of any integral type.
16024 The non-type parameter might use already deduced type parameters. */
16025 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16026 if (!TREE_TYPE (arg))
16027 /* Template-parameter dependent expression. Just accept it for now.
16028 It will later be processed in convert_template_argument. */
16030 else if (same_type_p (TREE_TYPE (arg), tparm))
16032 else if ((strict & UNIFY_ALLOW_INTEGER)
16033 && (TREE_CODE (tparm) == INTEGER_TYPE
16034 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16035 /* Convert the ARG to the type of PARM; the deduced non-type
16036 template argument must exactly match the types of the
16037 corresponding parameter. */
16038 arg = fold (build_nop (tparm, arg));
16039 else if (uses_template_parms (tparm))
16040 /* We haven't deduced the type of this parameter yet. Try again
16042 return unify_success (explain_p);
16044 return unify_type_mismatch (explain_p, tparm, arg);
16046 /* If ARG is a parameter pack or an expansion, we cannot unify
16047 against it unless PARM is also a parameter pack. */
16048 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16049 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16050 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16052 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16053 return unify_success (explain_p);
16057 /* A pointer-to-member constant can be unified only with
16058 another constant. */
16059 if (TREE_CODE (arg) != PTRMEM_CST)
16060 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16062 /* Just unify the class member. It would be useless (and possibly
16063 wrong, depending on the strict flags) to unify also
16064 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16065 arg refer to the same variable, even if through different
16066 classes. For instance:
16068 struct A { int x; };
16071 Unification of &A::x and &B::x must succeed. */
16072 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16073 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16078 if (TREE_CODE (arg) != POINTER_TYPE)
16079 return unify_type_mismatch (explain_p, parm, arg);
16081 /* [temp.deduct.call]
16083 A can be another pointer or pointer to member type that can
16084 be converted to the deduced A via a qualification
16085 conversion (_conv.qual_).
16087 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16088 This will allow for additional cv-qualification of the
16089 pointed-to types if appropriate. */
16091 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16092 /* The derived-to-base conversion only persists through one
16093 level of pointers. */
16094 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16096 return unify (tparms, targs, TREE_TYPE (parm),
16097 TREE_TYPE (arg), strict, explain_p);
16100 case REFERENCE_TYPE:
16101 if (TREE_CODE (arg) != REFERENCE_TYPE)
16102 return unify_type_mismatch (explain_p, parm, arg);
16103 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16104 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16107 if (TREE_CODE (arg) != ARRAY_TYPE)
16108 return unify_type_mismatch (explain_p, parm, arg);
16109 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16110 != (TYPE_DOMAIN (arg) == NULL_TREE))
16111 return unify_type_mismatch (explain_p, parm, arg);
16112 if (TYPE_DOMAIN (parm) != NULL_TREE)
16119 /* Our representation of array types uses "N - 1" as the
16120 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16121 not an integer constant. We cannot unify arbitrarily
16122 complex expressions, so we eliminate the MINUS_EXPRs
16124 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16125 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16128 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16129 parm_max = TREE_OPERAND (parm_max, 0);
16131 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16132 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16135 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16136 trying to unify the type of a variable with the type
16137 of a template parameter. For example:
16139 template <unsigned int N>
16140 void f (char (&) [N]);
16147 Here, the type of the ARG will be "int [g(i)]", and
16148 may be a SAVE_EXPR, etc. */
16149 if (TREE_CODE (arg_max) != MINUS_EXPR)
16150 return unify_vla_arg (explain_p, arg);
16151 arg_max = TREE_OPERAND (arg_max, 0);
16154 /* If only one of the bounds used a MINUS_EXPR, compensate
16155 by adding one to the other bound. */
16156 if (parm_cst && !arg_cst)
16157 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16161 else if (arg_cst && !parm_cst)
16162 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16167 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16168 UNIFY_ALLOW_INTEGER, explain_p);
16170 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16171 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16178 case ENUMERAL_TYPE:
16180 if (TREE_CODE (arg) != TREE_CODE (parm))
16181 return unify_type_mismatch (explain_p, parm, arg);
16183 /* We have already checked cv-qualification at the top of the
16185 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16186 return unify_type_mismatch (explain_p, parm, arg);
16188 /* As far as unification is concerned, this wins. Later checks
16189 will invalidate it if necessary. */
16190 return unify_success (explain_p);
16192 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16193 /* Type INTEGER_CST can come from ordinary constant template args. */
16195 while (TREE_CODE (arg) == NOP_EXPR)
16196 arg = TREE_OPERAND (arg, 0);
16198 if (TREE_CODE (arg) != INTEGER_CST)
16199 return unify_template_argument_mismatch (explain_p, parm, arg);
16200 return (tree_int_cst_equal (parm, arg)
16201 ? unify_success (explain_p)
16202 : unify_template_argument_mismatch (explain_p, parm, arg));
16207 if (TREE_CODE (arg) != TREE_VEC)
16208 return unify_template_argument_mismatch (explain_p, parm, arg);
16209 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
16210 return unify_arity (explain_p, TREE_VEC_LENGTH (arg),
16211 TREE_VEC_LENGTH (parm));
16212 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
16213 RECUR_AND_CHECK_FAILURE (tparms, targs,
16214 TREE_VEC_ELT (parm, i),
16215 TREE_VEC_ELT (arg, i),
16216 UNIFY_ALLOW_NONE, explain_p);
16217 return unify_success (explain_p);
16222 if (TREE_CODE (arg) != TREE_CODE (parm))
16223 return unify_type_mismatch (explain_p, parm, arg);
16225 if (TYPE_PTRMEMFUNC_P (parm))
16227 if (!TYPE_PTRMEMFUNC_P (arg))
16228 return unify_type_mismatch (explain_p, parm, arg);
16230 return unify (tparms, targs,
16231 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16232 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16233 strict, explain_p);
16236 if (CLASSTYPE_TEMPLATE_INFO (parm))
16238 tree t = NULL_TREE;
16240 if (strict_in & UNIFY_ALLOW_DERIVED)
16242 /* First, we try to unify the PARM and ARG directly. */
16243 t = try_class_unification (tparms, targs,
16244 parm, arg, explain_p);
16248 /* Fallback to the special case allowed in
16249 [temp.deduct.call]:
16251 If P is a class, and P has the form
16252 template-id, then A can be a derived class of
16253 the deduced A. Likewise, if P is a pointer to
16254 a class of the form template-id, A can be a
16255 pointer to a derived class pointed to by the
16257 enum template_base_result r;
16258 r = get_template_base (tparms, targs, parm, arg,
16262 return unify_no_common_base (explain_p, r, parm, arg);
16265 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16266 && (CLASSTYPE_TI_TEMPLATE (parm)
16267 == CLASSTYPE_TI_TEMPLATE (arg)))
16268 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16269 Then, we should unify `int' and `U'. */
16272 /* There's no chance of unification succeeding. */
16273 return unify_type_mismatch (explain_p, parm, arg);
16275 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16276 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16278 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16279 return unify_type_mismatch (explain_p, parm, arg);
16280 return unify_success (explain_p);
16283 case FUNCTION_TYPE:
16285 unsigned int nargs;
16290 if (TREE_CODE (arg) != TREE_CODE (parm))
16291 return unify_type_mismatch (explain_p, parm, arg);
16293 /* CV qualifications for methods can never be deduced, they must
16294 match exactly. We need to check them explicitly here,
16295 because type_unification_real treats them as any other
16296 cv-qualified parameter. */
16297 if (TREE_CODE (parm) == METHOD_TYPE
16298 && (!check_cv_quals_for_unify
16300 class_of_this_parm (arg),
16301 class_of_this_parm (parm))))
16302 return unify_cv_qual_mismatch (explain_p, parm, arg);
16304 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16305 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16307 nargs = list_length (TYPE_ARG_TYPES (arg));
16308 args = XALLOCAVEC (tree, nargs);
16309 for (a = TYPE_ARG_TYPES (arg), i = 0;
16310 a != NULL_TREE && a != void_list_node;
16311 a = TREE_CHAIN (a), ++i)
16312 args[i] = TREE_VALUE (a);
16315 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16316 args, nargs, 1, DEDUCE_EXACT,
16317 LOOKUP_NORMAL, explain_p);
16321 /* Unify a pointer to member with a pointer to member function, which
16322 deduces the type of the member as a function type. */
16323 if (TYPE_PTRMEMFUNC_P (arg))
16328 /* Check top-level cv qualifiers */
16329 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16330 return unify_cv_qual_mismatch (explain_p, parm, arg);
16332 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16333 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16334 UNIFY_ALLOW_NONE, explain_p);
16336 /* Determine the type of the function we are unifying against. */
16337 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16339 build_function_type (TREE_TYPE (method_type),
16340 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16342 /* Extract the cv-qualifiers of the member function from the
16343 implicit object parameter and place them on the function
16344 type to be restored later. */
16345 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16346 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16349 if (TREE_CODE (arg) != OFFSET_TYPE)
16350 return unify_type_mismatch (explain_p, parm, arg);
16351 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16352 TYPE_OFFSET_BASETYPE (arg),
16353 UNIFY_ALLOW_NONE, explain_p);
16354 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16355 strict, explain_p);
16358 if (DECL_TEMPLATE_PARM_P (parm))
16359 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16360 if (arg != integral_constant_value (parm))
16361 return unify_template_argument_mismatch (explain_p, parm, arg);
16362 return unify_success (explain_p);
16365 case TEMPLATE_DECL:
16366 /* Matched cases are handled by the ARG == PARM test above. */
16367 return unify_template_argument_mismatch (explain_p, parm, arg);
16370 /* A non-type template parameter that is a variable should be a
16371 an integral constant, in which case, it whould have been
16372 folded into its (constant) value. So we should not be getting
16373 a variable here. */
16374 gcc_unreachable ();
16376 case TYPE_ARGUMENT_PACK:
16377 case NONTYPE_ARGUMENT_PACK:
16379 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
16380 tree packed_args = ARGUMENT_PACK_ARGS (arg);
16381 int i, len = TREE_VEC_LENGTH (packed_parms);
16382 int argslen = TREE_VEC_LENGTH (packed_args);
16383 int parm_variadic_p = 0;
16385 for (i = 0; i < len; ++i)
16387 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
16390 /* We can unify against something with a trailing
16392 parm_variadic_p = 1;
16394 /* Since there is something following the pack
16395 expansion, we cannot unify this template argument
16397 return unify_success (explain_p);
16402 /* If we don't have enough arguments to satisfy the parameters
16403 (not counting the pack expression at the end), or we have
16404 too many arguments for a parameter list that doesn't end in
16405 a pack expression, we can't unify. */
16406 if (argslen < (len - parm_variadic_p))
16407 return unify_too_few_arguments (explain_p, argslen, len);
16408 if (argslen > len && !parm_variadic_p)
16409 return unify_too_many_arguments (explain_p, argslen, len);
16411 /* Unify all of the parameters that precede the (optional)
16412 pack expression. */
16413 for (i = 0; i < len - parm_variadic_p; ++i)
16415 RECUR_AND_CHECK_FAILURE (tparms, targs,
16416 TREE_VEC_ELT (packed_parms, i),
16417 TREE_VEC_ELT (packed_args, i),
16418 strict, explain_p);
16421 if (parm_variadic_p)
16422 return unify_pack_expansion (tparms, targs,
16423 packed_parms, packed_args,
16424 strict, /*call_args_p=*/false,
16425 /*subr=*/false, explain_p);
16426 return unify_success (explain_p);
16432 case DECLTYPE_TYPE:
16433 case UNDERLYING_TYPE:
16434 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16435 or UNDERLYING_TYPE nodes. */
16436 return unify_success (explain_p);
16439 /* Unification fails if we hit an error node. */
16440 return unify_invalid (explain_p);
16443 /* An unresolved overload is a nondeduced context. */
16444 if (type_unknown_p (parm))
16445 return unify_success (explain_p);
16446 gcc_assert (EXPR_P (parm));
16448 /* We must be looking at an expression. This can happen with
16452 void foo(S<I>, S<I + 2>);
16454 This is a "nondeduced context":
16458 The nondeduced contexts are:
16460 --A type that is a template-id in which one or more of
16461 the template-arguments is an expression that references
16462 a template-parameter.
16464 In these cases, we assume deduction succeeded, but don't
16465 actually infer any unifications. */
16467 if (!uses_template_parms (parm)
16468 && !template_args_equal (parm, arg))
16469 return unify_expression_unequal (explain_p, parm, arg);
16471 return unify_success (explain_p);
16474 #undef RECUR_AND_CHECK_FAILURE
16476 /* Note that DECL can be defined in this translation unit, if
16480 mark_definable (tree decl)
16483 DECL_NOT_REALLY_EXTERN (decl) = 1;
16484 FOR_EACH_CLONE (clone, decl)
16485 DECL_NOT_REALLY_EXTERN (clone) = 1;
16488 /* Called if RESULT is explicitly instantiated, or is a member of an
16489 explicitly instantiated class. */
16492 mark_decl_instantiated (tree result, int extern_p)
16494 SET_DECL_EXPLICIT_INSTANTIATION (result);
16496 /* If this entity has already been written out, it's too late to
16497 make any modifications. */
16498 if (TREE_ASM_WRITTEN (result))
16501 if (TREE_CODE (result) != FUNCTION_DECL)
16502 /* The TREE_PUBLIC flag for function declarations will have been
16503 set correctly by tsubst. */
16504 TREE_PUBLIC (result) = 1;
16506 /* This might have been set by an earlier implicit instantiation. */
16507 DECL_COMDAT (result) = 0;
16510 DECL_NOT_REALLY_EXTERN (result) = 0;
16513 mark_definable (result);
16514 /* Always make artificials weak. */
16515 if (DECL_ARTIFICIAL (result) && flag_weak)
16516 comdat_linkage (result);
16517 /* For WIN32 we also want to put explicit instantiations in
16518 linkonce sections. */
16519 else if (TREE_PUBLIC (result))
16520 maybe_make_one_only (result);
16523 /* If EXTERN_P, then this function will not be emitted -- unless
16524 followed by an explicit instantiation, at which point its linkage
16525 will be adjusted. If !EXTERN_P, then this function will be
16526 emitted here. In neither circumstance do we want
16527 import_export_decl to adjust the linkage. */
16528 DECL_INTERFACE_KNOWN (result) = 1;
16531 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16532 important template arguments. If any are missing, we check whether
16533 they're important by using error_mark_node for substituting into any
16534 args that were used for partial ordering (the ones between ARGS and END)
16535 and seeing if it bubbles up. */
16538 check_undeduced_parms (tree targs, tree args, tree end)
16540 bool found = false;
16542 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16543 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16546 TREE_VEC_ELT (targs, i) = error_mark_node;
16550 for (; args != end; args = TREE_CHAIN (args))
16552 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16553 if (substed == error_mark_node)
16560 /* Given two function templates PAT1 and PAT2, return:
16562 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16563 -1 if PAT2 is more specialized than PAT1.
16564 0 if neither is more specialized.
16566 LEN indicates the number of parameters we should consider
16567 (defaulted parameters should not be considered).
16569 The 1998 std underspecified function template partial ordering, and
16570 DR214 addresses the issue. We take pairs of arguments, one from
16571 each of the templates, and deduce them against each other. One of
16572 the templates will be more specialized if all the *other*
16573 template's arguments deduce against its arguments and at least one
16574 of its arguments *does* *not* deduce against the other template's
16575 corresponding argument. Deduction is done as for class templates.
16576 The arguments used in deduction have reference and top level cv
16577 qualifiers removed. Iff both arguments were originally reference
16578 types *and* deduction succeeds in both directions, the template
16579 with the more cv-qualified argument wins for that pairing (if
16580 neither is more cv-qualified, they both are equal). Unlike regular
16581 deduction, after all the arguments have been deduced in this way,
16582 we do *not* verify the deduced template argument values can be
16583 substituted into non-deduced contexts.
16585 The logic can be a bit confusing here, because we look at deduce1 and
16586 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16587 can find template arguments for pat1 to make arg1 look like arg2, that
16588 means that arg2 is at least as specialized as arg1. */
16591 more_specialized_fn (tree pat1, tree pat2, int len)
16593 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16594 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16595 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16596 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16597 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16598 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16599 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16600 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16601 tree origs1, origs2;
16602 bool lose1 = false;
16603 bool lose2 = false;
16605 /* Remove the this parameter from non-static member functions. If
16606 one is a non-static member function and the other is not a static
16607 member function, remove the first parameter from that function
16608 also. This situation occurs for operator functions where we
16609 locate both a member function (with this pointer) and non-member
16610 operator (with explicit first operand). */
16611 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16613 len--; /* LEN is the number of significant arguments for DECL1 */
16614 args1 = TREE_CHAIN (args1);
16615 if (!DECL_STATIC_FUNCTION_P (decl2))
16616 args2 = TREE_CHAIN (args2);
16618 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16620 args2 = TREE_CHAIN (args2);
16621 if (!DECL_STATIC_FUNCTION_P (decl1))
16624 args1 = TREE_CHAIN (args1);
16628 /* If only one is a conversion operator, they are unordered. */
16629 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16632 /* Consider the return type for a conversion function */
16633 if (DECL_CONV_FN_P (decl1))
16635 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16636 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16640 processing_template_decl++;
16646 /* Stop when an ellipsis is seen. */
16647 && args1 != NULL_TREE && args2 != NULL_TREE)
16649 tree arg1 = TREE_VALUE (args1);
16650 tree arg2 = TREE_VALUE (args2);
16651 int deduce1, deduce2;
16655 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16656 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16658 /* When both arguments are pack expansions, we need only
16659 unify the patterns themselves. */
16660 arg1 = PACK_EXPANSION_PATTERN (arg1);
16661 arg2 = PACK_EXPANSION_PATTERN (arg2);
16663 /* This is the last comparison we need to do. */
16667 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16669 arg1 = TREE_TYPE (arg1);
16670 quals1 = cp_type_quals (arg1);
16673 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16675 arg2 = TREE_TYPE (arg2);
16676 quals2 = cp_type_quals (arg2);
16679 if ((quals1 < 0) != (quals2 < 0))
16681 /* Only of the args is a reference, see if we should apply
16682 array/function pointer decay to it. This is not part of
16683 DR214, but is, IMHO, consistent with the deduction rules
16684 for the function call itself, and with our earlier
16685 implementation of the underspecified partial ordering
16686 rules. (nathan). */
16689 switch (TREE_CODE (arg1))
16692 arg1 = TREE_TYPE (arg1);
16694 case FUNCTION_TYPE:
16695 arg1 = build_pointer_type (arg1);
16704 switch (TREE_CODE (arg2))
16707 arg2 = TREE_TYPE (arg2);
16709 case FUNCTION_TYPE:
16710 arg2 = build_pointer_type (arg2);
16719 arg1 = TYPE_MAIN_VARIANT (arg1);
16720 arg2 = TYPE_MAIN_VARIANT (arg2);
16722 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16724 int i, len2 = list_length (args2);
16725 tree parmvec = make_tree_vec (1);
16726 tree argvec = make_tree_vec (len2);
16729 /* Setup the parameter vector, which contains only ARG1. */
16730 TREE_VEC_ELT (parmvec, 0) = arg1;
16732 /* Setup the argument vector, which contains the remaining
16734 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16735 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16737 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
16738 argvec, UNIFY_ALLOW_NONE,
16739 /*call_args_p=*/false,
16740 /*subr=*/0, /*explain_p=*/false)
16743 /* We cannot deduce in the other direction, because ARG1 is
16744 a pack expansion but ARG2 is not. */
16747 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16749 int i, len1 = list_length (args1);
16750 tree parmvec = make_tree_vec (1);
16751 tree argvec = make_tree_vec (len1);
16754 /* Setup the parameter vector, which contains only ARG1. */
16755 TREE_VEC_ELT (parmvec, 0) = arg2;
16757 /* Setup the argument vector, which contains the remaining
16759 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16760 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16762 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
16763 argvec, UNIFY_ALLOW_NONE,
16764 /*call_args_p=*/false,
16765 /*subr=*/0, /*explain_p=*/false)
16768 /* We cannot deduce in the other direction, because ARG2 is
16769 a pack expansion but ARG1 is not.*/
16775 /* The normal case, where neither argument is a pack
16777 deduce1 = (unify (tparms1, targs1, arg1, arg2,
16778 UNIFY_ALLOW_NONE, /*explain_p=*/false)
16780 deduce2 = (unify (tparms2, targs2, arg2, arg1,
16781 UNIFY_ALLOW_NONE, /*explain_p=*/false)
16785 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16786 arg2, then arg2 is not as specialized as arg1. */
16792 /* "If, for a given type, deduction succeeds in both directions
16793 (i.e., the types are identical after the transformations above)
16794 and if the type from the argument template is more cv-qualified
16795 than the type from the parameter template (as described above)
16796 that type is considered to be more specialized than the other. If
16797 neither type is more cv-qualified than the other then neither type
16798 is more specialized than the other." */
16800 if (deduce1 && deduce2
16801 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16803 if ((quals1 & quals2) == quals2)
16805 if ((quals1 & quals2) == quals1)
16809 if (lose1 && lose2)
16810 /* We've failed to deduce something in either direction.
16811 These must be unordered. */
16814 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16815 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16816 /* We have already processed all of the arguments in our
16817 handing of the pack expansion type. */
16820 args1 = TREE_CHAIN (args1);
16821 args2 = TREE_CHAIN (args2);
16824 /* "In most cases, all template parameters must have values in order for
16825 deduction to succeed, but for partial ordering purposes a template
16826 parameter may remain without a value provided it is not used in the
16827 types being used for partial ordering."
16829 Thus, if we are missing any of the targs1 we need to substitute into
16830 origs1, then pat2 is not as specialized as pat1. This can happen when
16831 there is a nondeduced context. */
16832 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16834 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16837 processing_template_decl--;
16839 /* All things being equal, if the next argument is a pack expansion
16840 for one function but not for the other, prefer the
16841 non-variadic function. FIXME this is bogus; see c++/41958. */
16843 && args1 && TREE_VALUE (args1)
16844 && args2 && TREE_VALUE (args2))
16846 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16847 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16850 if (lose1 == lose2)
16858 /* Determine which of two partial specializations is more specialized.
16860 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16861 to the first partial specialization. The TREE_VALUE is the
16862 innermost set of template parameters for the partial
16863 specialization. PAT2 is similar, but for the second template.
16865 Return 1 if the first partial specialization is more specialized;
16866 -1 if the second is more specialized; 0 if neither is more
16869 See [temp.class.order] for information about determining which of
16870 two templates is more specialized. */
16873 more_specialized_class (tree pat1, tree pat2)
16878 bool any_deductions = false;
16880 tmpl1 = TREE_TYPE (pat1);
16881 tmpl2 = TREE_TYPE (pat2);
16883 /* Just like what happens for functions, if we are ordering between
16884 different class template specializations, we may encounter dependent
16885 types in the arguments, and we need our dependency check functions
16886 to behave correctly. */
16887 ++processing_template_decl;
16888 targs = get_class_bindings (TREE_VALUE (pat1),
16889 CLASSTYPE_TI_ARGS (tmpl1),
16890 CLASSTYPE_TI_ARGS (tmpl2));
16894 any_deductions = true;
16897 targs = get_class_bindings (TREE_VALUE (pat2),
16898 CLASSTYPE_TI_ARGS (tmpl2),
16899 CLASSTYPE_TI_ARGS (tmpl1));
16903 any_deductions = true;
16905 --processing_template_decl;
16907 /* In the case of a tie where at least one of the class templates
16908 has a parameter pack at the end, the template with the most
16909 non-packed parameters wins. */
16912 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16913 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16915 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16916 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16917 int len1 = TREE_VEC_LENGTH (args1);
16918 int len2 = TREE_VEC_LENGTH (args2);
16920 /* We don't count the pack expansion at the end. */
16921 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
16923 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
16928 else if (len1 < len2)
16935 /* Return the template arguments that will produce the function signature
16936 DECL from the function template FN, with the explicit template
16937 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
16938 also match. Return NULL_TREE if no satisfactory arguments could be
16942 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
16944 int ntparms = DECL_NTPARMS (fn);
16945 tree targs = make_tree_vec (ntparms);
16947 tree decl_arg_types;
16949 unsigned int nargs, ix;
16952 /* Substitute the explicit template arguments into the type of DECL.
16953 The call to fn_type_unification will handle substitution into the
16955 decl_type = TREE_TYPE (decl);
16956 if (explicit_args && uses_template_parms (decl_type))
16959 tree converted_args;
16961 if (DECL_TEMPLATE_INFO (decl))
16962 tmpl = DECL_TI_TEMPLATE (decl);
16964 /* We can get here for some invalid specializations. */
16968 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
16969 explicit_args, NULL_TREE,
16971 /*require_all_args=*/false,
16972 /*use_default_args=*/false);
16973 if (converted_args == error_mark_node)
16976 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
16977 if (decl_type == error_mark_node)
16981 /* Never do unification on the 'this' parameter. */
16982 decl_arg_types = skip_artificial_parms_for (decl,
16983 TYPE_ARG_TYPES (decl_type));
16985 nargs = list_length (decl_arg_types);
16986 args = XALLOCAVEC (tree, nargs);
16987 for (arg = decl_arg_types, ix = 0;
16988 arg != NULL_TREE && arg != void_list_node;
16989 arg = TREE_CHAIN (arg), ++ix)
16990 args[ix] = TREE_VALUE (arg);
16992 if (fn_type_unification (fn, explicit_args, targs,
16994 (check_rettype || DECL_CONV_FN_P (fn)
16995 ? TREE_TYPE (decl_type) : NULL_TREE),
16996 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17002 /* Return the innermost template arguments that, when applied to a
17003 template specialization whose innermost template parameters are
17004 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17007 For example, suppose we have:
17009 template <class T, class U> struct S {};
17010 template <class T> struct S<T*, int> {};
17012 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17013 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17014 int}. The resulting vector will be {double}, indicating that `T'
17015 is bound to `double'. */
17018 get_class_bindings (tree tparms, tree spec_args, tree args)
17020 int i, ntparms = TREE_VEC_LENGTH (tparms);
17022 tree innermost_deduced_args;
17024 innermost_deduced_args = make_tree_vec (ntparms);
17025 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17027 deduced_args = copy_node (args);
17028 SET_TMPL_ARGS_LEVEL (deduced_args,
17029 TMPL_ARGS_DEPTH (deduced_args),
17030 innermost_deduced_args);
17033 deduced_args = innermost_deduced_args;
17035 if (unify (tparms, deduced_args,
17036 INNERMOST_TEMPLATE_ARGS (spec_args),
17037 INNERMOST_TEMPLATE_ARGS (args),
17038 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17041 for (i = 0; i < ntparms; ++i)
17042 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17045 /* Verify that nondeduced template arguments agree with the type
17046 obtained from argument deduction.
17050 struct A { typedef int X; };
17051 template <class T, class U> struct C {};
17052 template <class T> struct C<T, typename T::X> {};
17054 Then with the instantiation `C<A, int>', we can deduce that
17055 `T' is `A' but unify () does not check whether `typename T::X'
17057 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17058 if (spec_args == error_mark_node
17059 /* We only need to check the innermost arguments; the other
17060 arguments will always agree. */
17061 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17062 INNERMOST_TEMPLATE_ARGS (args)))
17065 /* Now that we have bindings for all of the template arguments,
17066 ensure that the arguments deduced for the template template
17067 parameters have compatible template parameter lists. See the use
17068 of template_template_parm_bindings_ok_p in fn_type_unification
17069 for more information. */
17070 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17073 return deduced_args;
17076 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17077 Return the TREE_LIST node with the most specialized template, if
17078 any. If there is no most specialized template, the error_mark_node
17081 Note that this function does not look at, or modify, the
17082 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17083 returned is one of the elements of INSTANTIATIONS, callers may
17084 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17085 and retrieve it from the value returned. */
17088 most_specialized_instantiation (tree templates)
17092 ++processing_template_decl;
17095 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17099 if (get_bindings (TREE_VALUE (champ),
17100 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17101 NULL_TREE, /*check_ret=*/true))
17104 if (get_bindings (TREE_VALUE (fn),
17105 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17106 NULL_TREE, /*check_ret=*/true))
17113 /* Equally specialized, move to next function. If there
17114 is no next function, nothing's most specialized. */
17115 fn = TREE_CHAIN (fn);
17123 /* Now verify that champ is better than everything earlier in the
17124 instantiation list. */
17125 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17126 if (get_bindings (TREE_VALUE (champ),
17127 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17128 NULL_TREE, /*check_ret=*/true)
17129 || !get_bindings (TREE_VALUE (fn),
17130 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17131 NULL_TREE, /*check_ret=*/true))
17137 processing_template_decl--;
17140 return error_mark_node;
17145 /* If DECL is a specialization of some template, return the most
17146 general such template. Otherwise, returns NULL_TREE.
17148 For example, given:
17150 template <class T> struct S { template <class U> void f(U); };
17152 if TMPL is `template <class U> void S<int>::f(U)' this will return
17153 the full template. This function will not trace past partial
17154 specializations, however. For example, given in addition:
17156 template <class T> struct S<T*> { template <class U> void f(U); };
17158 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17159 `template <class T> template <class U> S<T*>::f(U)'. */
17162 most_general_template (tree decl)
17164 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17165 an immediate specialization. */
17166 if (TREE_CODE (decl) == FUNCTION_DECL)
17168 if (DECL_TEMPLATE_INFO (decl)) {
17169 decl = DECL_TI_TEMPLATE (decl);
17171 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17172 template friend. */
17173 if (TREE_CODE (decl) != TEMPLATE_DECL)
17179 /* Look for more and more general templates. */
17180 while (DECL_TEMPLATE_INFO (decl))
17182 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17183 (See cp-tree.h for details.) */
17184 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17187 if (CLASS_TYPE_P (TREE_TYPE (decl))
17188 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17191 /* Stop if we run into an explicitly specialized class template. */
17192 if (!DECL_NAMESPACE_SCOPE_P (decl)
17193 && DECL_CONTEXT (decl)
17194 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17197 decl = DECL_TI_TEMPLATE (decl);
17203 /* Return the most specialized of the class template partial
17204 specializations of TMPL which can produce TYPE, a specialization of
17205 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17206 a _TYPE node corresponding to the partial specialization, while the
17207 TREE_PURPOSE is the set of template arguments that must be
17208 substituted into the TREE_TYPE in order to generate TYPE.
17210 If the choice of partial specialization is ambiguous, a diagnostic
17211 is issued, and the error_mark_node is returned. If there are no
17212 partial specializations of TMPL matching TYPE, then NULL_TREE is
17216 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17218 tree list = NULL_TREE;
17224 tree outer_args = NULL_TREE;
17226 tmpl = most_general_template (tmpl);
17227 args = CLASSTYPE_TI_ARGS (type);
17229 /* For determining which partial specialization to use, only the
17230 innermost args are interesting. */
17231 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17233 outer_args = strip_innermost_template_args (args, 1);
17234 args = INNERMOST_TEMPLATE_ARGS (args);
17237 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17239 tree partial_spec_args;
17241 tree parms = TREE_VALUE (t);
17243 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17245 ++processing_template_decl;
17251 /* Discard the outer levels of args, and then substitute in the
17252 template args from the enclosing class. */
17253 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17254 partial_spec_args = tsubst_template_args
17255 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17257 /* PARMS already refers to just the innermost parms, but the
17258 template parms in partial_spec_args had their levels lowered
17259 by tsubst, so we need to do the same for the parm list. We
17260 can't just tsubst the TREE_VEC itself, as tsubst wants to
17261 treat a TREE_VEC as an argument vector. */
17262 parms = copy_node (parms);
17263 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17264 TREE_VEC_ELT (parms, i) =
17265 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17269 partial_spec_args =
17270 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17271 add_to_template_args (outer_args,
17272 partial_spec_args),
17274 /*require_all_args=*/true,
17275 /*use_default_args=*/true);
17277 --processing_template_decl;
17279 if (partial_spec_args == error_mark_node)
17280 return error_mark_node;
17282 spec_args = get_class_bindings (parms,
17288 spec_args = add_to_template_args (outer_args, spec_args);
17289 list = tree_cons (spec_args, TREE_VALUE (t), list);
17290 TREE_TYPE (list) = TREE_TYPE (t);
17297 ambiguous_p = false;
17300 t = TREE_CHAIN (t);
17301 for (; t; t = TREE_CHAIN (t))
17303 fate = more_specialized_class (champ, t);
17310 t = TREE_CHAIN (t);
17313 ambiguous_p = true;
17322 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17324 fate = more_specialized_class (champ, t);
17327 ambiguous_p = true;
17335 char *spaces = NULL;
17336 if (!(complain & tf_error))
17337 return error_mark_node;
17338 error ("ambiguous class template instantiation for %q#T", type);
17339 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17340 for (t = list; t; t = TREE_CHAIN (t))
17342 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17343 spaces = spaces ? spaces : get_spaces (str);
17346 return error_mark_node;
17352 /* Explicitly instantiate DECL. */
17355 do_decl_instantiation (tree decl, tree storage)
17357 tree result = NULL_TREE;
17360 if (!decl || decl == error_mark_node)
17361 /* An error occurred, for which grokdeclarator has already issued
17362 an appropriate message. */
17364 else if (! DECL_LANG_SPECIFIC (decl))
17366 error ("explicit instantiation of non-template %q#D", decl);
17369 else if (TREE_CODE (decl) == VAR_DECL)
17371 /* There is an asymmetry here in the way VAR_DECLs and
17372 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17373 the latter, the DECL we get back will be marked as a
17374 template instantiation, and the appropriate
17375 DECL_TEMPLATE_INFO will be set up. This does not happen for
17376 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17377 should handle VAR_DECLs as it currently handles
17379 if (!DECL_CLASS_SCOPE_P (decl))
17381 error ("%qD is not a static data member of a class template", decl);
17384 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17385 if (!result || TREE_CODE (result) != VAR_DECL)
17387 error ("no matching template for %qD found", decl);
17390 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17392 error ("type %qT for explicit instantiation %qD does not match "
17393 "declared type %qT", TREE_TYPE (result), decl,
17398 else if (TREE_CODE (decl) != FUNCTION_DECL)
17400 error ("explicit instantiation of %q#D", decl);
17406 /* Check for various error cases. Note that if the explicit
17407 instantiation is valid the RESULT will currently be marked as an
17408 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17409 until we get here. */
17411 if (DECL_TEMPLATE_SPECIALIZATION (result))
17413 /* DR 259 [temp.spec].
17415 Both an explicit instantiation and a declaration of an explicit
17416 specialization shall not appear in a program unless the explicit
17417 instantiation follows a declaration of the explicit specialization.
17419 For a given set of template parameters, if an explicit
17420 instantiation of a template appears after a declaration of an
17421 explicit specialization for that template, the explicit
17422 instantiation has no effect. */
17425 else if (DECL_EXPLICIT_INSTANTIATION (result))
17429 No program shall explicitly instantiate any template more
17432 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17433 the first instantiation was `extern' and the second is not,
17434 and EXTERN_P for the opposite case. */
17435 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17436 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17437 /* If an "extern" explicit instantiation follows an ordinary
17438 explicit instantiation, the template is instantiated. */
17442 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17444 error ("no matching template for %qD found", result);
17447 else if (!DECL_TEMPLATE_INFO (result))
17449 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17453 if (storage == NULL_TREE)
17455 else if (storage == ridpointers[(int) RID_EXTERN])
17457 if (!in_system_header && (cxx_dialect == cxx98))
17458 pedwarn (input_location, OPT_pedantic,
17459 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17464 error ("storage class %qD applied to template instantiation", storage);
17466 check_explicit_instantiation_namespace (result);
17467 mark_decl_instantiated (result, extern_p);
17469 instantiate_decl (result, /*defer_ok=*/1,
17470 /*expl_inst_class_mem_p=*/false);
17474 mark_class_instantiated (tree t, int extern_p)
17476 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17477 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17478 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17479 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17482 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17483 rest_of_type_compilation (t, 1);
17487 /* Called from do_type_instantiation through binding_table_foreach to
17488 do recursive instantiation for the type bound in ENTRY. */
17490 bt_instantiate_type_proc (binding_entry entry, void *data)
17492 tree storage = *(tree *) data;
17494 if (MAYBE_CLASS_TYPE_P (entry->type)
17495 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17496 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17499 /* Called from do_type_instantiation to instantiate a member
17500 (a member function or a static member variable) of an
17501 explicitly instantiated class template. */
17503 instantiate_class_member (tree decl, int extern_p)
17505 mark_decl_instantiated (decl, extern_p);
17507 instantiate_decl (decl, /*defer_ok=*/1,
17508 /*expl_inst_class_mem_p=*/true);
17511 /* Perform an explicit instantiation of template class T. STORAGE, if
17512 non-null, is the RID for extern, inline or static. COMPLAIN is
17513 nonzero if this is called from the parser, zero if called recursively,
17514 since the standard is unclear (as detailed below). */
17517 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17522 int previous_instantiation_extern_p = 0;
17524 if (TREE_CODE (t) == TYPE_DECL)
17527 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17529 error ("explicit instantiation of non-template type %qT", t);
17535 if (!COMPLETE_TYPE_P (t))
17537 if (complain & tf_error)
17538 error ("explicit instantiation of %q#T before definition of template",
17543 if (storage != NULL_TREE)
17545 if (!in_system_header)
17547 if (storage == ridpointers[(int) RID_EXTERN])
17549 if (cxx_dialect == cxx98)
17550 pedwarn (input_location, OPT_pedantic,
17551 "ISO C++ 1998 forbids the use of %<extern%> on "
17552 "explicit instantiations");
17555 pedwarn (input_location, OPT_pedantic,
17556 "ISO C++ forbids the use of %qE"
17557 " on explicit instantiations", storage);
17560 if (storage == ridpointers[(int) RID_INLINE])
17562 else if (storage == ridpointers[(int) RID_EXTERN])
17564 else if (storage == ridpointers[(int) RID_STATIC])
17568 error ("storage class %qD applied to template instantiation",
17574 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17576 /* DR 259 [temp.spec].
17578 Both an explicit instantiation and a declaration of an explicit
17579 specialization shall not appear in a program unless the explicit
17580 instantiation follows a declaration of the explicit specialization.
17582 For a given set of template parameters, if an explicit
17583 instantiation of a template appears after a declaration of an
17584 explicit specialization for that template, the explicit
17585 instantiation has no effect. */
17588 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17592 No program shall explicitly instantiate any template more
17595 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17596 instantiation was `extern'. If EXTERN_P then the second is.
17597 These cases are OK. */
17598 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17600 if (!previous_instantiation_extern_p && !extern_p
17601 && (complain & tf_error))
17602 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17604 /* If we've already instantiated the template, just return now. */
17605 if (!CLASSTYPE_INTERFACE_ONLY (t))
17609 check_explicit_instantiation_namespace (TYPE_NAME (t));
17610 mark_class_instantiated (t, extern_p);
17618 /* In contrast to implicit instantiation, where only the
17619 declarations, and not the definitions, of members are
17620 instantiated, we have here:
17624 The explicit instantiation of a class template specialization
17625 implies the instantiation of all of its members not
17626 previously explicitly specialized in the translation unit
17627 containing the explicit instantiation.
17629 Of course, we can't instantiate member template classes, since
17630 we don't have any arguments for them. Note that the standard
17631 is unclear on whether the instantiation of the members are
17632 *explicit* instantiations or not. However, the most natural
17633 interpretation is that it should be an explicit instantiation. */
17636 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17637 if (TREE_CODE (tmp) == FUNCTION_DECL
17638 && DECL_TEMPLATE_INSTANTIATION (tmp))
17639 instantiate_class_member (tmp, extern_p);
17641 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17642 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17643 instantiate_class_member (tmp, extern_p);
17645 if (CLASSTYPE_NESTED_UTDS (t))
17646 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17647 bt_instantiate_type_proc, &storage);
17651 /* Given a function DECL, which is a specialization of TMPL, modify
17652 DECL to be a re-instantiation of TMPL with the same template
17653 arguments. TMPL should be the template into which tsubst'ing
17654 should occur for DECL, not the most general template.
17656 One reason for doing this is a scenario like this:
17659 void f(const T&, int i);
17661 void g() { f(3, 7); }
17664 void f(const T& t, const int i) { }
17666 Note that when the template is first instantiated, with
17667 instantiate_template, the resulting DECL will have no name for the
17668 first parameter, and the wrong type for the second. So, when we go
17669 to instantiate the DECL, we regenerate it. */
17672 regenerate_decl_from_template (tree decl, tree tmpl)
17674 /* The arguments used to instantiate DECL, from the most general
17679 args = DECL_TI_ARGS (decl);
17680 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17682 /* Make sure that we can see identifiers, and compute access
17684 push_access_scope (decl);
17686 if (TREE_CODE (decl) == FUNCTION_DECL)
17694 args_depth = TMPL_ARGS_DEPTH (args);
17695 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17696 if (args_depth > parms_depth)
17697 args = get_innermost_template_args (args, parms_depth);
17699 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17700 args, tf_error, NULL_TREE,
17701 /*defer_ok*/false);
17703 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17706 /* Merge parameter declarations. */
17707 decl_parm = skip_artificial_parms_for (decl,
17708 DECL_ARGUMENTS (decl));
17710 = skip_artificial_parms_for (code_pattern,
17711 DECL_ARGUMENTS (code_pattern));
17712 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17717 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17718 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17719 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17721 parm_type = type_decays_to (parm_type);
17722 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17723 TREE_TYPE (decl_parm) = parm_type;
17724 attributes = DECL_ATTRIBUTES (pattern_parm);
17725 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17727 DECL_ATTRIBUTES (decl_parm) = attributes;
17728 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17730 decl_parm = DECL_CHAIN (decl_parm);
17731 pattern_parm = DECL_CHAIN (pattern_parm);
17733 /* Merge any parameters that match with the function parameter
17735 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17738 tree expanded_types;
17739 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17740 the parameters in this function parameter pack. */
17741 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17742 args, tf_error, NULL_TREE);
17743 len = TREE_VEC_LENGTH (expanded_types);
17744 for (i = 0; i < len; i++)
17749 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17750 /* Rename the parameter to include the index. */
17751 DECL_NAME (decl_parm) =
17752 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17753 parm_type = TREE_VEC_ELT (expanded_types, i);
17754 parm_type = type_decays_to (parm_type);
17755 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17756 TREE_TYPE (decl_parm) = parm_type;
17757 attributes = DECL_ATTRIBUTES (pattern_parm);
17758 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17760 DECL_ATTRIBUTES (decl_parm) = attributes;
17761 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17763 decl_parm = DECL_CHAIN (decl_parm);
17766 /* Merge additional specifiers from the CODE_PATTERN. */
17767 if (DECL_DECLARED_INLINE_P (code_pattern)
17768 && !DECL_DECLARED_INLINE_P (decl))
17769 DECL_DECLARED_INLINE_P (decl) = 1;
17771 else if (TREE_CODE (decl) == VAR_DECL)
17773 DECL_INITIAL (decl) =
17774 tsubst_expr (DECL_INITIAL (code_pattern), args,
17775 tf_error, DECL_TI_TEMPLATE (decl),
17776 /*integral_constant_expression_p=*/false);
17777 if (VAR_HAD_UNKNOWN_BOUND (decl))
17778 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17779 tf_error, DECL_TI_TEMPLATE (decl));
17782 gcc_unreachable ();
17784 pop_access_scope (decl);
17787 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17788 substituted to get DECL. */
17791 template_for_substitution (tree decl)
17793 tree tmpl = DECL_TI_TEMPLATE (decl);
17795 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17796 for the instantiation. This is not always the most general
17797 template. Consider, for example:
17800 struct S { template <class U> void f();
17801 template <> void f<int>(); };
17803 and an instantiation of S<double>::f<int>. We want TD to be the
17804 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17805 while (/* An instantiation cannot have a definition, so we need a
17806 more general template. */
17807 DECL_TEMPLATE_INSTANTIATION (tmpl)
17808 /* We must also deal with friend templates. Given:
17810 template <class T> struct S {
17811 template <class U> friend void f() {};
17814 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17815 so far as the language is concerned, but that's still
17816 where we get the pattern for the instantiation from. On
17817 other hand, if the definition comes outside the class, say:
17819 template <class T> struct S {
17820 template <class U> friend void f();
17822 template <class U> friend void f() {}
17824 we don't need to look any further. That's what the check for
17825 DECL_INITIAL is for. */
17826 || (TREE_CODE (decl) == FUNCTION_DECL
17827 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17828 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17830 /* The present template, TD, should not be a definition. If it
17831 were a definition, we should be using it! Note that we
17832 cannot restructure the loop to just keep going until we find
17833 a template with a definition, since that might go too far if
17834 a specialization was declared, but not defined. */
17835 gcc_assert (TREE_CODE (decl) != VAR_DECL
17836 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17838 /* Fetch the more general template. */
17839 tmpl = DECL_TI_TEMPLATE (tmpl);
17845 /* Returns true if we need to instantiate this template instance even if we
17846 know we aren't going to emit it.. */
17849 always_instantiate_p (tree decl)
17851 /* We always instantiate inline functions so that we can inline them. An
17852 explicit instantiation declaration prohibits implicit instantiation of
17853 non-inline functions. With high levels of optimization, we would
17854 normally inline non-inline functions -- but we're not allowed to do
17855 that for "extern template" functions. Therefore, we check
17856 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17857 return ((TREE_CODE (decl) == FUNCTION_DECL
17858 && DECL_DECLARED_INLINE_P (decl))
17859 /* And we need to instantiate static data members so that
17860 their initializers are available in integral constant
17862 || (TREE_CODE (decl) == VAR_DECL
17863 && decl_maybe_constant_var_p (decl)));
17866 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
17867 instantiate it now, modifying TREE_TYPE (fn). */
17870 maybe_instantiate_noexcept (tree fn)
17872 tree fntype, spec, noex, clone;
17874 if (DECL_CLONED_FUNCTION_P (fn))
17875 fn = DECL_CLONED_FUNCTION (fn);
17876 fntype = TREE_TYPE (fn);
17877 spec = TYPE_RAISES_EXCEPTIONS (fntype);
17879 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
17882 noex = TREE_PURPOSE (spec);
17884 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
17886 push_tinst_level (fn);
17887 push_access_scope (fn);
17888 input_location = DECL_SOURCE_LOCATION (fn);
17889 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
17890 DEFERRED_NOEXCEPT_ARGS (noex),
17891 tf_warning_or_error, fn, /*function_p=*/false,
17892 /*integral_constant_expression_p=*/true);
17893 pop_access_scope (fn);
17894 pop_tinst_level ();
17895 spec = build_noexcept_spec (noex, tf_warning_or_error);
17896 if (spec == error_mark_node)
17897 spec = noexcept_false_spec;
17901 /* This is an implicitly declared function, so NOEX is a list of
17902 other functions to evaluate and merge. */
17904 spec = noexcept_true_spec;
17905 for (elt = noex; elt; elt = OVL_NEXT (elt))
17907 tree fn = OVL_CURRENT (elt);
17909 maybe_instantiate_noexcept (fn);
17910 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
17911 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
17915 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
17917 FOR_EACH_CLONE (clone, fn)
17919 if (TREE_TYPE (clone) == fntype)
17920 TREE_TYPE (clone) = TREE_TYPE (fn);
17922 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
17926 /* Produce the definition of D, a _DECL generated from a template. If
17927 DEFER_OK is nonzero, then we don't have to actually do the
17928 instantiation now; we just have to do it sometime. Normally it is
17929 an error if this is an explicit instantiation but D is undefined.
17930 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
17931 explicitly instantiated class template. */
17934 instantiate_decl (tree d, int defer_ok,
17935 bool expl_inst_class_mem_p)
17937 tree tmpl = DECL_TI_TEMPLATE (d);
17944 bool pattern_defined;
17946 location_t saved_loc = input_location;
17949 /* This function should only be used to instantiate templates for
17950 functions and static member variables. */
17951 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
17952 || TREE_CODE (d) == VAR_DECL);
17954 /* Variables are never deferred; if instantiation is required, they
17955 are instantiated right away. That allows for better code in the
17956 case that an expression refers to the value of the variable --
17957 if the variable has a constant value the referring expression can
17958 take advantage of that fact. */
17959 if (TREE_CODE (d) == VAR_DECL
17960 || DECL_DECLARED_CONSTEXPR_P (d))
17963 /* Don't instantiate cloned functions. Instead, instantiate the
17964 functions they cloned. */
17965 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
17966 d = DECL_CLONED_FUNCTION (d);
17968 if (DECL_TEMPLATE_INSTANTIATED (d)
17969 || DECL_TEMPLATE_SPECIALIZATION (d))
17970 /* D has already been instantiated or explicitly specialized, so
17971 there's nothing for us to do here.
17973 It might seem reasonable to check whether or not D is an explicit
17974 instantiation, and, if so, stop here. But when an explicit
17975 instantiation is deferred until the end of the compilation,
17976 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
17977 the instantiation. */
17980 /* Check to see whether we know that this template will be
17981 instantiated in some other file, as with "extern template"
17983 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
17985 /* In general, we do not instantiate such templates. */
17986 if (external_p && !always_instantiate_p (d))
17989 gen_tmpl = most_general_template (tmpl);
17990 gen_args = DECL_TI_ARGS (d);
17992 if (tmpl != gen_tmpl)
17993 /* We should already have the extra args. */
17994 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
17995 == TMPL_ARGS_DEPTH (gen_args));
17996 /* And what's in the hash table should match D. */
17997 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
17998 || spec == NULL_TREE);
18000 /* This needs to happen before any tsubsting. */
18001 if (! push_tinst_level (d))
18004 timevar_push (TV_TEMPLATE_INST);
18006 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18007 for the instantiation. */
18008 td = template_for_substitution (d);
18009 code_pattern = DECL_TEMPLATE_RESULT (td);
18011 /* We should never be trying to instantiate a member of a class
18012 template or partial specialization. */
18013 gcc_assert (d != code_pattern);
18015 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18016 || DECL_TEMPLATE_SPECIALIZATION (td))
18017 /* In the case of a friend template whose definition is provided
18018 outside the class, we may have too many arguments. Drop the
18019 ones we don't need. The same is true for specializations. */
18020 args = get_innermost_template_args
18021 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18025 if (TREE_CODE (d) == FUNCTION_DECL)
18026 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18027 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18029 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18031 /* We may be in the middle of deferred access check. Disable it now. */
18032 push_deferring_access_checks (dk_no_deferred);
18034 /* Unless an explicit instantiation directive has already determined
18035 the linkage of D, remember that a definition is available for
18037 if (pattern_defined
18038 && !DECL_INTERFACE_KNOWN (d)
18039 && !DECL_NOT_REALLY_EXTERN (d))
18040 mark_definable (d);
18042 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18043 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18044 input_location = DECL_SOURCE_LOCATION (d);
18046 /* If D is a member of an explicitly instantiated class template,
18047 and no definition is available, treat it like an implicit
18049 if (!pattern_defined && expl_inst_class_mem_p
18050 && DECL_EXPLICIT_INSTANTIATION (d))
18052 /* Leave linkage flags alone on instantiations with anonymous
18054 if (TREE_PUBLIC (d))
18056 DECL_NOT_REALLY_EXTERN (d) = 0;
18057 DECL_INTERFACE_KNOWN (d) = 0;
18059 SET_DECL_IMPLICIT_INSTANTIATION (d);
18062 if (TREE_CODE (d) == FUNCTION_DECL)
18063 maybe_instantiate_noexcept (d);
18065 /* Recheck the substitutions to obtain any warning messages
18066 about ignoring cv qualifiers. Don't do this for artificial decls,
18067 as it breaks the context-sensitive substitution for lambda op(). */
18068 if (!defer_ok && !DECL_ARTIFICIAL (d))
18070 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18071 tree type = TREE_TYPE (gen);
18073 /* Make sure that we can see identifiers, and compute access
18074 correctly. D is already the target FUNCTION_DECL with the
18076 push_access_scope (d);
18078 if (TREE_CODE (gen) == FUNCTION_DECL)
18080 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18081 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18082 d, /*defer_ok*/true);
18083 /* Don't simply tsubst the function type, as that will give
18084 duplicate warnings about poor parameter qualifications.
18085 The function arguments are the same as the decl_arguments
18086 without the top level cv qualifiers. */
18087 type = TREE_TYPE (type);
18089 tsubst (type, gen_args, tf_warning_or_error, d);
18091 pop_access_scope (d);
18094 /* Defer all other templates, unless we have been explicitly
18095 forbidden from doing so. */
18096 if (/* If there is no definition, we cannot instantiate the
18099 /* If it's OK to postpone instantiation, do so. */
18101 /* If this is a static data member that will be defined
18102 elsewhere, we don't want to instantiate the entire data
18103 member, but we do want to instantiate the initializer so that
18104 we can substitute that elsewhere. */
18105 || (external_p && TREE_CODE (d) == VAR_DECL))
18107 /* The definition of the static data member is now required so
18108 we must substitute the initializer. */
18109 if (TREE_CODE (d) == VAR_DECL
18110 && !DECL_INITIAL (d)
18111 && DECL_INITIAL (code_pattern))
18115 bool const_init = false;
18117 ns = decl_namespace_context (d);
18118 push_nested_namespace (ns);
18119 push_nested_class (DECL_CONTEXT (d));
18120 init = tsubst_expr (DECL_INITIAL (code_pattern),
18122 tf_warning_or_error, NULL_TREE,
18123 /*integral_constant_expression_p=*/false);
18124 /* Make sure the initializer is still constant, in case of
18125 circular dependency (template/instantiate6.C). */
18127 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18128 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18129 /*asmspec_tree=*/NULL_TREE,
18130 LOOKUP_ONLYCONVERTING);
18131 pop_nested_class ();
18132 pop_nested_namespace (ns);
18135 /* We restore the source position here because it's used by
18136 add_pending_template. */
18137 input_location = saved_loc;
18139 if (at_eof && !pattern_defined
18140 && DECL_EXPLICIT_INSTANTIATION (d)
18141 && DECL_NOT_REALLY_EXTERN (d))
18144 The definition of a non-exported function template, a
18145 non-exported member function template, or a non-exported
18146 member function or static data member of a class template
18147 shall be present in every translation unit in which it is
18148 explicitly instantiated. */
18149 permerror (input_location, "explicit instantiation of %qD "
18150 "but no definition available", d);
18152 /* If we're in unevaluated context, we just wanted to get the
18153 constant value; this isn't an odr use, so don't queue
18154 a full instantiation. */
18155 if (cp_unevaluated_operand != 0)
18157 /* ??? Historically, we have instantiated inline functions, even
18158 when marked as "extern template". */
18159 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18160 add_pending_template (d);
18163 /* Tell the repository that D is available in this translation unit
18164 -- and see if it is supposed to be instantiated here. */
18165 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18167 /* In a PCH file, despite the fact that the repository hasn't
18168 requested instantiation in the PCH it is still possible that
18169 an instantiation will be required in a file that includes the
18172 add_pending_template (d);
18173 /* Instantiate inline functions so that the inliner can do its
18174 job, even though we'll not be emitting a copy of this
18176 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18180 need_push = !cfun || !global_bindings_p ();
18182 push_to_top_level ();
18184 /* Mark D as instantiated so that recursive calls to
18185 instantiate_decl do not try to instantiate it again. */
18186 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18188 /* Regenerate the declaration in case the template has been modified
18189 by a subsequent redeclaration. */
18190 regenerate_decl_from_template (d, td);
18192 /* We already set the file and line above. Reset them now in case
18193 they changed as a result of calling regenerate_decl_from_template. */
18194 input_location = DECL_SOURCE_LOCATION (d);
18196 if (TREE_CODE (d) == VAR_DECL)
18199 bool const_init = false;
18201 /* Clear out DECL_RTL; whatever was there before may not be right
18202 since we've reset the type of the declaration. */
18203 SET_DECL_RTL (d, NULL);
18204 DECL_IN_AGGR_P (d) = 0;
18206 /* The initializer is placed in DECL_INITIAL by
18207 regenerate_decl_from_template so we don't need to
18208 push/pop_access_scope again here. Pull it out so that
18209 cp_finish_decl can process it. */
18210 init = DECL_INITIAL (d);
18211 DECL_INITIAL (d) = NULL_TREE;
18212 DECL_INITIALIZED_P (d) = 0;
18214 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18215 initializer. That function will defer actual emission until
18216 we have a chance to determine linkage. */
18217 DECL_EXTERNAL (d) = 0;
18219 /* Enter the scope of D so that access-checking works correctly. */
18220 push_nested_class (DECL_CONTEXT (d));
18221 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18222 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18223 pop_nested_class ();
18225 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18226 synthesize_method (d);
18227 else if (TREE_CODE (d) == FUNCTION_DECL)
18229 htab_t saved_local_specializations;
18234 /* Save away the current list, in case we are instantiating one
18235 template from within the body of another. */
18236 saved_local_specializations = local_specializations;
18238 /* Set up the list of local specializations. */
18239 local_specializations = htab_create (37,
18240 hash_local_specialization,
18241 eq_local_specializations,
18244 /* Set up context. */
18245 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18247 /* Create substitution entries for the parameters. */
18248 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18249 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18250 spec_parm = DECL_ARGUMENTS (d);
18251 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18253 register_local_specialization (spec_parm, tmpl_parm);
18254 spec_parm = skip_artificial_parms_for (d, spec_parm);
18255 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18257 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18259 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18261 register_local_specialization (spec_parm, tmpl_parm);
18262 spec_parm = DECL_CHAIN (spec_parm);
18266 /* Register the (value) argument pack as a specialization of
18267 TMPL_PARM, then move on. */
18268 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18269 register_local_specialization (argpack, tmpl_parm);
18272 gcc_assert (!spec_parm);
18274 /* Substitute into the body of the function. */
18275 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18276 tf_warning_or_error, tmpl,
18277 /*integral_constant_expression_p=*/false);
18279 /* Set the current input_location to the end of the function
18280 so that finish_function knows where we are. */
18281 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18283 /* We don't need the local specializations any more. */
18284 htab_delete (local_specializations);
18285 local_specializations = saved_local_specializations;
18287 /* Finish the function. */
18288 d = finish_function (0);
18289 expand_or_defer_fn (d);
18292 /* We're not deferring instantiation any more. */
18293 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18296 pop_from_top_level ();
18299 input_location = saved_loc;
18300 pop_deferring_access_checks ();
18301 pop_tinst_level ();
18303 timevar_pop (TV_TEMPLATE_INST);
18308 /* Run through the list of templates that we wish we could
18309 instantiate, and instantiate any we can. RETRIES is the
18310 number of times we retry pending template instantiation. */
18313 instantiate_pending_templates (int retries)
18316 location_t saved_loc = input_location;
18318 /* Instantiating templates may trigger vtable generation. This in turn
18319 may require further template instantiations. We place a limit here
18320 to avoid infinite loop. */
18321 if (pending_templates && retries >= max_tinst_depth)
18323 tree decl = pending_templates->tinst->decl;
18325 error ("template instantiation depth exceeds maximum of %d"
18326 " instantiating %q+D, possibly from virtual table generation"
18327 " (use -ftemplate-depth= to increase the maximum)",
18328 max_tinst_depth, decl);
18329 if (TREE_CODE (decl) == FUNCTION_DECL)
18330 /* Pretend that we defined it. */
18331 DECL_INITIAL (decl) = error_mark_node;
18337 struct pending_template **t = &pending_templates;
18338 struct pending_template *last = NULL;
18342 tree instantiation = reopen_tinst_level ((*t)->tinst);
18343 bool complete = false;
18345 if (TYPE_P (instantiation))
18349 if (!COMPLETE_TYPE_P (instantiation))
18351 instantiate_class_template (instantiation);
18352 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18353 for (fn = TYPE_METHODS (instantiation);
18355 fn = TREE_CHAIN (fn))
18356 if (! DECL_ARTIFICIAL (fn))
18357 instantiate_decl (fn,
18359 /*expl_inst_class_mem_p=*/false);
18360 if (COMPLETE_TYPE_P (instantiation))
18364 complete = COMPLETE_TYPE_P (instantiation);
18368 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18369 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18372 = instantiate_decl (instantiation,
18374 /*expl_inst_class_mem_p=*/false);
18375 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18379 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18380 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18384 /* If INSTANTIATION has been instantiated, then we don't
18385 need to consider it again in the future. */
18393 current_tinst_level = NULL;
18395 last_pending_template = last;
18397 while (reconsider);
18399 input_location = saved_loc;
18402 /* Substitute ARGVEC into T, which is a list of initializers for
18403 either base class or a non-static data member. The TREE_PURPOSEs
18404 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18405 instantiate_decl. */
18408 tsubst_initializer_list (tree t, tree argvec)
18410 tree inits = NULL_TREE;
18412 for (; t; t = TREE_CHAIN (t))
18416 tree expanded_bases = NULL_TREE;
18417 tree expanded_arguments = NULL_TREE;
18420 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18425 /* Expand the base class expansion type into separate base
18427 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18428 tf_warning_or_error,
18430 if (expanded_bases == error_mark_node)
18433 /* We'll be building separate TREE_LISTs of arguments for
18435 len = TREE_VEC_LENGTH (expanded_bases);
18436 expanded_arguments = make_tree_vec (len);
18437 for (i = 0; i < len; i++)
18438 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18440 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18441 expand each argument in the TREE_VALUE of t. */
18442 expr = make_node (EXPR_PACK_EXPANSION);
18443 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18444 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18446 if (TREE_VALUE (t) == void_type_node)
18447 /* VOID_TYPE_NODE is used to indicate
18448 value-initialization. */
18450 for (i = 0; i < len; i++)
18451 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18455 /* Substitute parameter packs into each argument in the
18457 in_base_initializer = 1;
18458 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18460 tree expanded_exprs;
18462 /* Expand the argument. */
18463 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18465 = tsubst_pack_expansion (expr, argvec,
18466 tf_warning_or_error,
18468 if (expanded_exprs == error_mark_node)
18471 /* Prepend each of the expanded expressions to the
18472 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18473 for (i = 0; i < len; i++)
18475 TREE_VEC_ELT (expanded_arguments, i) =
18476 tree_cons (NULL_TREE,
18477 TREE_VEC_ELT (expanded_exprs, i),
18478 TREE_VEC_ELT (expanded_arguments, i));
18481 in_base_initializer = 0;
18483 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18484 since we built them backwards. */
18485 for (i = 0; i < len; i++)
18487 TREE_VEC_ELT (expanded_arguments, i) =
18488 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18493 for (i = 0; i < len; ++i)
18495 if (expanded_bases)
18497 decl = TREE_VEC_ELT (expanded_bases, i);
18498 decl = expand_member_init (decl);
18499 init = TREE_VEC_ELT (expanded_arguments, i);
18503 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18504 tf_warning_or_error, NULL_TREE);
18506 decl = expand_member_init (decl);
18507 if (decl && !DECL_P (decl))
18508 in_base_initializer = 1;
18510 init = TREE_VALUE (t);
18511 if (init != void_type_node)
18512 init = tsubst_expr (init, argvec,
18513 tf_warning_or_error, NULL_TREE,
18514 /*integral_constant_expression_p=*/false);
18515 in_base_initializer = 0;
18520 init = build_tree_list (decl, init);
18521 TREE_CHAIN (init) = inits;
18529 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18532 set_current_access_from_decl (tree decl)
18534 if (TREE_PRIVATE (decl))
18535 current_access_specifier = access_private_node;
18536 else if (TREE_PROTECTED (decl))
18537 current_access_specifier = access_protected_node;
18539 current_access_specifier = access_public_node;
18542 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18543 is the instantiation (which should have been created with
18544 start_enum) and ARGS are the template arguments to use. */
18547 tsubst_enum (tree tag, tree newtag, tree args)
18551 if (SCOPED_ENUM_P (newtag))
18552 begin_scope (sk_scoped_enum, newtag);
18554 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18559 decl = TREE_VALUE (e);
18560 /* Note that in a template enum, the TREE_VALUE is the
18561 CONST_DECL, not the corresponding INTEGER_CST. */
18562 value = tsubst_expr (DECL_INITIAL (decl),
18563 args, tf_warning_or_error, NULL_TREE,
18564 /*integral_constant_expression_p=*/true);
18566 /* Give this enumeration constant the correct access. */
18567 set_current_access_from_decl (decl);
18569 /* Actually build the enumerator itself. */
18571 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
18574 if (SCOPED_ENUM_P (newtag))
18577 finish_enum_value_list (newtag);
18578 finish_enum (newtag);
18580 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
18581 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
18584 /* DECL is a FUNCTION_DECL that is a template specialization. Return
18585 its type -- but without substituting the innermost set of template
18586 arguments. So, innermost set of template parameters will appear in
18590 get_mostly_instantiated_function_type (tree decl)
18598 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
18599 targs = DECL_TI_ARGS (decl);
18600 tparms = DECL_TEMPLATE_PARMS (tmpl);
18601 parm_depth = TMPL_PARMS_DEPTH (tparms);
18603 /* There should be as many levels of arguments as there are levels
18605 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18607 fn_type = TREE_TYPE (tmpl);
18609 if (parm_depth == 1)
18610 /* No substitution is necessary. */
18617 /* Replace the innermost level of the TARGS with NULL_TREEs to
18618 let tsubst know not to substitute for those parameters. */
18619 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18620 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18621 SET_TMPL_ARGS_LEVEL (partial_args, i,
18622 TMPL_ARGS_LEVEL (targs, i));
18623 SET_TMPL_ARGS_LEVEL (partial_args,
18624 TMPL_ARGS_DEPTH (targs),
18625 make_tree_vec (DECL_NTPARMS (tmpl)));
18627 /* Make sure that we can see identifiers, and compute access
18629 push_access_scope (decl);
18631 ++processing_template_decl;
18632 /* Now, do the (partial) substitution to figure out the
18633 appropriate function type. */
18634 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
18635 --processing_template_decl;
18637 /* Substitute into the template parameters to obtain the real
18638 innermost set of parameters. This step is important if the
18639 innermost set of template parameters contains value
18640 parameters whose types depend on outer template parameters. */
18641 TREE_VEC_LENGTH (partial_args)--;
18642 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
18644 pop_access_scope (decl);
18650 /* Return truthvalue if we're processing a template different from
18651 the last one involved in diagnostics. */
18653 problematic_instantiation_changed (void)
18655 return current_tinst_level != last_error_tinst_level;
18658 /* Remember current template involved in diagnostics. */
18660 record_last_problematic_instantiation (void)
18662 last_error_tinst_level = current_tinst_level;
18665 struct tinst_level *
18666 current_instantiation (void)
18668 return current_tinst_level;
18671 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18672 type. Return zero for ok, nonzero for disallowed. Issue error and
18673 warning messages under control of COMPLAIN. */
18676 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18678 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18680 else if (POINTER_TYPE_P (type))
18682 else if (TYPE_PTR_TO_MEMBER_P (type))
18684 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18686 else if (TREE_CODE (type) == TYPENAME_TYPE)
18688 else if (TREE_CODE (type) == DECLTYPE_TYPE)
18691 if (complain & tf_error)
18692 error ("%q#T is not a valid type for a template constant parameter", type);
18696 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18697 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18700 dependent_type_p_r (tree type)
18706 A type is dependent if it is:
18708 -- a template parameter. Template template parameters are types
18709 for us (since TYPE_P holds true for them) so we handle
18711 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18712 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18714 /* -- a qualified-id with a nested-name-specifier which contains a
18715 class-name that names a dependent type or whose unqualified-id
18716 names a dependent type. */
18717 if (TREE_CODE (type) == TYPENAME_TYPE)
18719 /* -- a cv-qualified type where the cv-unqualified type is
18721 type = TYPE_MAIN_VARIANT (type);
18722 /* -- a compound type constructed from any dependent type. */
18723 if (TYPE_PTR_TO_MEMBER_P (type))
18724 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18725 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18727 else if (TREE_CODE (type) == POINTER_TYPE
18728 || TREE_CODE (type) == REFERENCE_TYPE)
18729 return dependent_type_p (TREE_TYPE (type));
18730 else if (TREE_CODE (type) == FUNCTION_TYPE
18731 || TREE_CODE (type) == METHOD_TYPE)
18735 if (dependent_type_p (TREE_TYPE (type)))
18737 for (arg_type = TYPE_ARG_TYPES (type);
18739 arg_type = TREE_CHAIN (arg_type))
18740 if (dependent_type_p (TREE_VALUE (arg_type)))
18744 /* -- an array type constructed from any dependent type or whose
18745 size is specified by a constant expression that is
18748 We checked for type- and value-dependence of the bounds in
18749 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18750 if (TREE_CODE (type) == ARRAY_TYPE)
18752 if (TYPE_DOMAIN (type)
18753 && dependent_type_p (TYPE_DOMAIN (type)))
18755 return dependent_type_p (TREE_TYPE (type));
18758 /* -- a template-id in which either the template name is a template
18760 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18762 /* ... or any of the template arguments is a dependent type or
18763 an expression that is type-dependent or value-dependent. */
18764 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18765 && (any_dependent_template_arguments_p
18766 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18769 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18770 dependent; if the argument of the `typeof' expression is not
18771 type-dependent, then it should already been have resolved. */
18772 if (TREE_CODE (type) == TYPEOF_TYPE
18773 || TREE_CODE (type) == DECLTYPE_TYPE
18774 || TREE_CODE (type) == UNDERLYING_TYPE)
18777 /* A template argument pack is dependent if any of its packed
18779 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18781 tree args = ARGUMENT_PACK_ARGS (type);
18782 int i, len = TREE_VEC_LENGTH (args);
18783 for (i = 0; i < len; ++i)
18784 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18788 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18789 be template parameters. */
18790 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18793 /* The standard does not specifically mention types that are local
18794 to template functions or local classes, but they should be
18795 considered dependent too. For example:
18797 template <int I> void f() {
18802 The size of `E' cannot be known until the value of `I' has been
18803 determined. Therefore, `E' must be considered dependent. */
18804 scope = TYPE_CONTEXT (type);
18805 if (scope && TYPE_P (scope))
18806 return dependent_type_p (scope);
18807 /* Don't use type_dependent_expression_p here, as it can lead
18808 to infinite recursion trying to determine whether a lambda
18809 nested in a lambda is dependent (c++/47687). */
18810 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
18811 && DECL_LANG_SPECIFIC (scope)
18812 && DECL_TEMPLATE_INFO (scope)
18813 && (any_dependent_template_arguments_p
18814 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
18817 /* Other types are non-dependent. */
18821 /* Returns TRUE if TYPE is dependent, in the sense of
18822 [temp.dep.type]. Note that a NULL type is considered dependent. */
18825 dependent_type_p (tree type)
18827 /* If there are no template parameters in scope, then there can't be
18828 any dependent types. */
18829 if (!processing_template_decl)
18831 /* If we are not processing a template, then nobody should be
18832 providing us with a dependent type. */
18834 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18838 /* If the type is NULL, we have not computed a type for the entity
18839 in question; in that case, the type is dependent. */
18843 /* Erroneous types can be considered non-dependent. */
18844 if (type == error_mark_node)
18847 /* If we have not already computed the appropriate value for TYPE,
18849 if (!TYPE_DEPENDENT_P_VALID (type))
18851 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18852 TYPE_DEPENDENT_P_VALID (type) = 1;
18855 return TYPE_DEPENDENT_P (type);
18858 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18859 lookup. In other words, a dependent type that is not the current
18863 dependent_scope_p (tree scope)
18865 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18866 && !currently_open_class (scope));
18869 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18870 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18873 /* Note that this predicate is not appropriate for general expressions;
18874 only constant expressions (that satisfy potential_constant_expression)
18875 can be tested for value dependence.
18877 We should really also have a predicate for "instantiation-dependent".
18879 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18880 (what about instantiation-dependent constant-expressions?)
18881 is_late_template_attribute: defer if instantiation-dependent.
18882 compute_array_index_type: proceed if constant and not t- or v-dependent
18883 if instantiation-dependent, need to remember full expression
18884 uses_template_parms: FIXME - need to audit callers
18885 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18886 dependent_type_p [array_type]: dependent if index type is dependent
18888 static_assert - instantiation-dependent */
18891 value_dependent_expression_p (tree expression)
18893 if (!processing_template_decl)
18896 /* A name declared with a dependent type. */
18897 if (DECL_P (expression) && type_dependent_expression_p (expression))
18900 switch (TREE_CODE (expression))
18902 case IDENTIFIER_NODE:
18903 /* A name that has not been looked up -- must be dependent. */
18906 case TEMPLATE_PARM_INDEX:
18907 /* A non-type template parm. */
18911 /* A non-type template parm. */
18912 if (DECL_TEMPLATE_PARM_P (expression))
18914 return value_dependent_expression_p (DECL_INITIAL (expression));
18917 /* A constant with literal type and is initialized
18918 with an expression that is value-dependent. */
18919 if (DECL_INITIAL (expression)
18920 && decl_constant_var_p (expression)
18921 && value_dependent_expression_p (DECL_INITIAL (expression)))
18925 case DYNAMIC_CAST_EXPR:
18926 case STATIC_CAST_EXPR:
18927 case CONST_CAST_EXPR:
18928 case REINTERPRET_CAST_EXPR:
18930 /* These expressions are value-dependent if the type to which
18931 the cast occurs is dependent or the expression being casted
18932 is value-dependent. */
18934 tree type = TREE_TYPE (expression);
18936 if (dependent_type_p (type))
18939 /* A functional cast has a list of operands. */
18940 expression = TREE_OPERAND (expression, 0);
18943 /* If there are no operands, it must be an expression such
18944 as "int()". This should not happen for aggregate types
18945 because it would form non-constant expressions. */
18946 gcc_assert (cxx_dialect >= cxx0x
18947 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
18952 if (TREE_CODE (expression) == TREE_LIST)
18953 return any_value_dependent_elements_p (expression);
18955 return value_dependent_expression_p (expression);
18961 /* A `sizeof' expression is value-dependent if the operand is
18962 type-dependent or is a pack expansion. */
18963 expression = TREE_OPERAND (expression, 0);
18964 if (PACK_EXPANSION_P (expression))
18966 else if (TYPE_P (expression))
18967 return dependent_type_p (expression);
18968 return type_dependent_expression_p (expression);
18970 case AT_ENCODE_EXPR:
18971 /* An 'encode' expression is value-dependent if the operand is
18973 expression = TREE_OPERAND (expression, 0);
18974 return dependent_type_p (expression);
18976 case NOEXCEPT_EXPR:
18977 expression = TREE_OPERAND (expression, 0);
18978 return type_dependent_expression_p (expression);
18982 tree name = TREE_OPERAND (expression, 1);
18983 return value_dependent_expression_p (name);
18986 case COMPONENT_REF:
18987 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
18988 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
18990 case NONTYPE_ARGUMENT_PACK:
18991 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
18992 is value-dependent. */
18994 tree values = ARGUMENT_PACK_ARGS (expression);
18995 int i, len = TREE_VEC_LENGTH (values);
18997 for (i = 0; i < len; ++i)
18998 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19006 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19007 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19008 || (type2 ? dependent_type_p (type2) : false));
19012 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19013 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19016 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19017 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19021 tree op = TREE_OPERAND (expression, 0);
19022 return (value_dependent_expression_p (op)
19023 || has_value_dependent_address (op));
19028 tree fn = get_callee_fndecl (expression);
19030 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19032 nargs = call_expr_nargs (expression);
19033 for (i = 0; i < nargs; ++i)
19035 tree op = CALL_EXPR_ARG (expression, i);
19036 /* In a call to a constexpr member function, look through the
19037 implicit ADDR_EXPR on the object argument so that it doesn't
19038 cause the call to be considered value-dependent. We also
19039 look through it in potential_constant_expression. */
19040 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19041 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19042 && TREE_CODE (op) == ADDR_EXPR)
19043 op = TREE_OPERAND (op, 0);
19044 if (value_dependent_expression_p (op))
19050 case TEMPLATE_ID_EXPR:
19051 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19053 return type_dependent_expression_p (expression);
19059 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19060 if (value_dependent_expression_p (val))
19066 /* A constant expression is value-dependent if any subexpression is
19067 value-dependent. */
19068 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19070 case tcc_reference:
19072 case tcc_comparison:
19074 case tcc_expression:
19077 int i, len = cp_tree_operand_length (expression);
19079 for (i = 0; i < len; i++)
19081 tree t = TREE_OPERAND (expression, i);
19083 /* In some cases, some of the operands may be missing.l
19084 (For example, in the case of PREDECREMENT_EXPR, the
19085 amount to increment by may be missing.) That doesn't
19086 make the expression dependent. */
19087 if (t && value_dependent_expression_p (t))
19098 /* The expression is not value-dependent. */
19102 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19103 [temp.dep.expr]. Note that an expression with no type is
19104 considered dependent. Other parts of the compiler arrange for an
19105 expression with type-dependent subexpressions to have no type, so
19106 this function doesn't have to be fully recursive. */
19109 type_dependent_expression_p (tree expression)
19111 if (!processing_template_decl)
19114 if (expression == error_mark_node)
19117 /* An unresolved name is always dependent. */
19118 if (TREE_CODE (expression) == IDENTIFIER_NODE
19119 || TREE_CODE (expression) == USING_DECL)
19122 /* Some expression forms are never type-dependent. */
19123 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19124 || TREE_CODE (expression) == SIZEOF_EXPR
19125 || TREE_CODE (expression) == ALIGNOF_EXPR
19126 || TREE_CODE (expression) == AT_ENCODE_EXPR
19127 || TREE_CODE (expression) == NOEXCEPT_EXPR
19128 || TREE_CODE (expression) == TRAIT_EXPR
19129 || TREE_CODE (expression) == TYPEID_EXPR
19130 || TREE_CODE (expression) == DELETE_EXPR
19131 || TREE_CODE (expression) == VEC_DELETE_EXPR
19132 || TREE_CODE (expression) == THROW_EXPR)
19135 /* The types of these expressions depends only on the type to which
19136 the cast occurs. */
19137 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19138 || TREE_CODE (expression) == STATIC_CAST_EXPR
19139 || TREE_CODE (expression) == CONST_CAST_EXPR
19140 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19141 || TREE_CODE (expression) == CAST_EXPR)
19142 return dependent_type_p (TREE_TYPE (expression));
19144 /* The types of these expressions depends only on the type created
19145 by the expression. */
19146 if (TREE_CODE (expression) == NEW_EXPR
19147 || TREE_CODE (expression) == VEC_NEW_EXPR)
19149 /* For NEW_EXPR tree nodes created inside a template, either
19150 the object type itself or a TREE_LIST may appear as the
19152 tree type = TREE_OPERAND (expression, 1);
19153 if (TREE_CODE (type) == TREE_LIST)
19154 /* This is an array type. We need to check array dimensions
19156 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19157 || value_dependent_expression_p
19158 (TREE_OPERAND (TREE_VALUE (type), 1));
19160 return dependent_type_p (type);
19163 if (TREE_CODE (expression) == SCOPE_REF)
19165 tree scope = TREE_OPERAND (expression, 0);
19166 tree name = TREE_OPERAND (expression, 1);
19168 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19169 contains an identifier associated by name lookup with one or more
19170 declarations declared with a dependent type, or...a
19171 nested-name-specifier or qualified-id that names a member of an
19172 unknown specialization. */
19173 return (type_dependent_expression_p (name)
19174 || dependent_scope_p (scope));
19177 if (TREE_CODE (expression) == FUNCTION_DECL
19178 && DECL_LANG_SPECIFIC (expression)
19179 && DECL_TEMPLATE_INFO (expression)
19180 && (any_dependent_template_arguments_p
19181 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19184 if (TREE_CODE (expression) == TEMPLATE_DECL
19185 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19188 if (TREE_CODE (expression) == STMT_EXPR)
19189 expression = stmt_expr_value_expr (expression);
19191 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19196 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19198 if (type_dependent_expression_p (elt))
19204 /* A static data member of the current instantiation with incomplete
19205 array type is type-dependent, as the definition and specializations
19206 can have different bounds. */
19207 if (TREE_CODE (expression) == VAR_DECL
19208 && DECL_CLASS_SCOPE_P (expression)
19209 && dependent_type_p (DECL_CONTEXT (expression))
19210 && VAR_HAD_UNKNOWN_BOUND (expression))
19213 if (TREE_TYPE (expression) == unknown_type_node)
19215 if (TREE_CODE (expression) == ADDR_EXPR)
19216 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19217 if (TREE_CODE (expression) == COMPONENT_REF
19218 || TREE_CODE (expression) == OFFSET_REF)
19220 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19222 expression = TREE_OPERAND (expression, 1);
19223 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19226 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19227 if (TREE_CODE (expression) == SCOPE_REF)
19230 if (TREE_CODE (expression) == BASELINK)
19231 expression = BASELINK_FUNCTIONS (expression);
19233 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19235 if (any_dependent_template_arguments_p
19236 (TREE_OPERAND (expression, 1)))
19238 expression = TREE_OPERAND (expression, 0);
19240 gcc_assert (TREE_CODE (expression) == OVERLOAD
19241 || TREE_CODE (expression) == FUNCTION_DECL);
19245 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19247 expression = OVL_NEXT (expression);
19252 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19254 return (dependent_type_p (TREE_TYPE (expression)));
19257 /* Like type_dependent_expression_p, but it also works while not processing
19258 a template definition, i.e. during substitution or mangling. */
19261 type_dependent_expression_p_push (tree expr)
19264 ++processing_template_decl;
19265 b = type_dependent_expression_p (expr);
19266 --processing_template_decl;
19270 /* Returns TRUE if ARGS contains a type-dependent expression. */
19273 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19278 FOR_EACH_VEC_ELT (tree, args, i, arg)
19280 if (type_dependent_expression_p (arg))
19286 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19287 expressions) contains any type-dependent expressions. */
19290 any_type_dependent_elements_p (const_tree list)
19292 for (; list; list = TREE_CHAIN (list))
19293 if (value_dependent_expression_p (TREE_VALUE (list)))
19299 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19300 expressions) contains any value-dependent expressions. */
19303 any_value_dependent_elements_p (const_tree list)
19305 for (; list; list = TREE_CHAIN (list))
19306 if (value_dependent_expression_p (TREE_VALUE (list)))
19312 /* Returns TRUE if the ARG (a template argument) is dependent. */
19315 dependent_template_arg_p (tree arg)
19317 if (!processing_template_decl)
19320 /* Assume a template argument that was wrongly written by the user
19321 is dependent. This is consistent with what
19322 any_dependent_template_arguments_p [that calls this function]
19324 if (!arg || arg == error_mark_node)
19327 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19328 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19330 if (TREE_CODE (arg) == TEMPLATE_DECL
19331 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19332 return dependent_template_p (arg);
19333 else if (ARGUMENT_PACK_P (arg))
19335 tree args = ARGUMENT_PACK_ARGS (arg);
19336 int i, len = TREE_VEC_LENGTH (args);
19337 for (i = 0; i < len; ++i)
19339 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19345 else if (TYPE_P (arg))
19346 return dependent_type_p (arg);
19348 return (type_dependent_expression_p (arg)
19349 || value_dependent_expression_p (arg));
19352 /* Returns true if ARGS (a collection of template arguments) contains
19353 any types that require structural equality testing. */
19356 any_template_arguments_need_structural_equality_p (tree args)
19363 if (args == error_mark_node)
19366 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19368 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19369 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19371 tree arg = TREE_VEC_ELT (level, j);
19372 tree packed_args = NULL_TREE;
19375 if (ARGUMENT_PACK_P (arg))
19377 /* Look inside the argument pack. */
19378 packed_args = ARGUMENT_PACK_ARGS (arg);
19379 len = TREE_VEC_LENGTH (packed_args);
19382 for (k = 0; k < len; ++k)
19385 arg = TREE_VEC_ELT (packed_args, k);
19387 if (error_operand_p (arg))
19389 else if (TREE_CODE (arg) == TEMPLATE_DECL
19390 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19392 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19394 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19395 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19404 /* Returns true if ARGS (a collection of template arguments) contains
19405 any dependent arguments. */
19408 any_dependent_template_arguments_p (const_tree args)
19415 if (args == error_mark_node)
19418 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19420 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19421 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19422 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19429 /* Returns TRUE if the template TMPL is dependent. */
19432 dependent_template_p (tree tmpl)
19434 if (TREE_CODE (tmpl) == OVERLOAD)
19438 if (dependent_template_p (OVL_CURRENT (tmpl)))
19440 tmpl = OVL_NEXT (tmpl);
19445 /* Template template parameters are dependent. */
19446 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19447 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19449 /* So are names that have not been looked up. */
19450 if (TREE_CODE (tmpl) == SCOPE_REF
19451 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19453 /* So are member templates of dependent classes. */
19454 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19455 return dependent_type_p (DECL_CONTEXT (tmpl));
19459 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19462 dependent_template_id_p (tree tmpl, tree args)
19464 return (dependent_template_p (tmpl)
19465 || any_dependent_template_arguments_p (args));
19468 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19472 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19476 if (!processing_template_decl)
19479 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19481 tree decl = TREE_VEC_ELT (declv, i);
19482 tree init = TREE_VEC_ELT (initv, i);
19483 tree cond = TREE_VEC_ELT (condv, i);
19484 tree incr = TREE_VEC_ELT (incrv, i);
19486 if (type_dependent_expression_p (decl))
19489 if (init && type_dependent_expression_p (init))
19492 if (type_dependent_expression_p (cond))
19495 if (COMPARISON_CLASS_P (cond)
19496 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19497 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19500 if (TREE_CODE (incr) == MODOP_EXPR)
19502 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19503 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19506 else if (type_dependent_expression_p (incr))
19508 else if (TREE_CODE (incr) == MODIFY_EXPR)
19510 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19512 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19514 tree t = TREE_OPERAND (incr, 1);
19515 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19516 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19525 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19526 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19527 no such TYPE can be found. Note that this function peers inside
19528 uninstantiated templates and therefore should be used only in
19529 extremely limited situations. ONLY_CURRENT_P restricts this
19530 peering to the currently open classes hierarchy (which is required
19531 when comparing types). */
19534 resolve_typename_type (tree type, bool only_current_p)
19543 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19545 scope = TYPE_CONTEXT (type);
19546 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19547 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19548 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19549 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19550 identifier of the TYPENAME_TYPE anymore.
19551 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19552 TYPENAME_TYPE instead, we avoid messing up with a possible
19553 typedef variant case. */
19554 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
19556 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
19557 it first before we can figure out what NAME refers to. */
19558 if (TREE_CODE (scope) == TYPENAME_TYPE)
19559 scope = resolve_typename_type (scope, only_current_p);
19560 /* If we don't know what SCOPE refers to, then we cannot resolve the
19562 if (TREE_CODE (scope) == TYPENAME_TYPE)
19564 /* If the SCOPE is a template type parameter, we have no way of
19565 resolving the name. */
19566 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
19568 /* If the SCOPE is not the current instantiation, there's no reason
19569 to look inside it. */
19570 if (only_current_p && !currently_open_class (scope))
19572 /* If this is a typedef, we don't want to look inside (c++/11987). */
19573 if (typedef_variant_p (type))
19575 /* If SCOPE isn't the template itself, it will not have a valid
19576 TYPE_FIELDS list. */
19577 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
19578 /* scope is either the template itself or a compatible instantiation
19579 like X<T>, so look up the name in the original template. */
19580 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
19582 /* scope is a partial instantiation, so we can't do the lookup or we
19583 will lose the template arguments. */
19585 /* Enter the SCOPE so that name lookup will be resolved as if we
19586 were in the class definition. In particular, SCOPE will no
19587 longer be considered a dependent type. */
19588 pushed_scope = push_scope (scope);
19589 /* Look up the declaration. */
19590 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
19592 result = NULL_TREE;
19594 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
19595 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
19598 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
19599 && TREE_CODE (decl) == TYPE_DECL)
19601 result = TREE_TYPE (decl);
19602 if (result == error_mark_node)
19603 result = NULL_TREE;
19605 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19606 && DECL_CLASS_TEMPLATE_P (decl))
19610 /* Obtain the template and the arguments. */
19611 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19612 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19613 /* Instantiate the template. */
19614 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
19615 /*entering_scope=*/0,
19616 tf_error | tf_user);
19617 if (result == error_mark_node)
19618 result = NULL_TREE;
19621 /* Leave the SCOPE. */
19623 pop_scope (pushed_scope);
19625 /* If we failed to resolve it, return the original typename. */
19629 /* If lookup found a typename type, resolve that too. */
19630 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
19632 /* Ill-formed programs can cause infinite recursion here, so we
19633 must catch that. */
19634 TYPENAME_IS_RESOLVING_P (type) = 1;
19635 result = resolve_typename_type (result, only_current_p);
19636 TYPENAME_IS_RESOLVING_P (type) = 0;
19639 /* Qualify the resulting type. */
19640 quals = cp_type_quals (type);
19642 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
19647 /* EXPR is an expression which is not type-dependent. Return a proxy
19648 for EXPR that can be used to compute the types of larger
19649 expressions containing EXPR. */
19652 build_non_dependent_expr (tree expr)
19656 #ifdef ENABLE_CHECKING
19657 /* Try to get a constant value for all non-type-dependent expressions in
19658 order to expose bugs in *_dependent_expression_p and constexpr. */
19659 if (cxx_dialect >= cxx0x)
19660 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
19663 /* Preserve OVERLOADs; the functions must be available to resolve
19666 if (TREE_CODE (inner_expr) == STMT_EXPR)
19667 inner_expr = stmt_expr_value_expr (inner_expr);
19668 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19669 inner_expr = TREE_OPERAND (inner_expr, 0);
19670 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19671 inner_expr = TREE_OPERAND (inner_expr, 1);
19672 if (is_overloaded_fn (inner_expr)
19673 || TREE_CODE (inner_expr) == OFFSET_REF)
19675 /* There is no need to return a proxy for a variable. */
19676 if (TREE_CODE (expr) == VAR_DECL)
19678 /* Preserve string constants; conversions from string constants to
19679 "char *" are allowed, even though normally a "const char *"
19680 cannot be used to initialize a "char *". */
19681 if (TREE_CODE (expr) == STRING_CST)
19683 /* Preserve arithmetic constants, as an optimization -- there is no
19684 reason to create a new node. */
19685 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19687 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19688 There is at least one place where we want to know that a
19689 particular expression is a throw-expression: when checking a ?:
19690 expression, there are special rules if the second or third
19691 argument is a throw-expression. */
19692 if (TREE_CODE (expr) == THROW_EXPR)
19695 /* Don't wrap an initializer list, we need to be able to look inside. */
19696 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
19699 if (TREE_CODE (expr) == COND_EXPR)
19700 return build3 (COND_EXPR,
19702 TREE_OPERAND (expr, 0),
19703 (TREE_OPERAND (expr, 1)
19704 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19705 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19706 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19707 if (TREE_CODE (expr) == COMPOUND_EXPR
19708 && !COMPOUND_EXPR_OVERLOADED (expr))
19709 return build2 (COMPOUND_EXPR,
19711 TREE_OPERAND (expr, 0),
19712 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19714 /* If the type is unknown, it can't really be non-dependent */
19715 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19717 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19718 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19721 /* ARGS is a vector of expressions as arguments to a function call.
19722 Replace the arguments with equivalent non-dependent expressions.
19723 This modifies ARGS in place. */
19726 make_args_non_dependent (VEC(tree,gc) *args)
19731 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19733 tree newarg = build_non_dependent_expr (arg);
19735 VEC_replace (tree, args, ix, newarg);
19739 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19740 with a level one deeper than the actual template parms. */
19745 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19746 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19747 TYPE_DECL, get_identifier ("auto"), au);
19748 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19749 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19750 (0, processing_template_decl + 1, processing_template_decl + 1,
19751 0, TYPE_NAME (au), NULL_TREE);
19752 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19753 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19754 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19759 /* Given type ARG, return std::initializer_list<ARG>. */
19764 tree std_init_list = namespace_binding
19765 (get_identifier ("initializer_list"), std_node);
19767 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19769 error ("deducing from brace-enclosed initializer list requires "
19770 "#include <initializer_list>");
19771 return error_mark_node;
19773 argvec = make_tree_vec (1);
19774 TREE_VEC_ELT (argvec, 0) = arg;
19775 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19776 NULL_TREE, 0, tf_warning_or_error);
19779 /* Replace auto in TYPE with std::initializer_list<auto>. */
19782 listify_autos (tree type, tree auto_node)
19784 tree init_auto = listify (auto_node);
19785 tree argvec = make_tree_vec (1);
19786 TREE_VEC_ELT (argvec, 0) = init_auto;
19787 if (processing_template_decl)
19788 argvec = add_to_template_args (current_template_args (), argvec);
19789 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19792 /* walk_tree helper for do_auto_deduction. */
19795 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19798 /* Is this a variable with the type we're looking for? */
19800 && TREE_TYPE (*tp) == type)
19806 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19807 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19810 do_auto_deduction (tree type, tree init, tree auto_node)
19812 tree parms, tparms, targs;
19817 if (processing_template_decl
19818 && (TREE_TYPE (init) == NULL_TREE
19819 || BRACE_ENCLOSED_INITIALIZER_P (init)))
19820 /* Not enough information to try this yet. */
19823 /* The name of the object being declared shall not appear in the
19824 initializer expression. */
19825 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19828 error ("variable %q#D with %<auto%> type used in its own "
19829 "initializer", decl);
19830 return error_mark_node;
19833 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19834 with either a new invented type template parameter U or, if the
19835 initializer is a braced-init-list (8.5.4), with
19836 std::initializer_list<U>. */
19837 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19838 type = listify_autos (type, auto_node);
19840 init = resolve_nondeduced_context (init);
19842 parms = build_tree_list (NULL_TREE, type);
19844 tparms = make_tree_vec (1);
19845 targs = make_tree_vec (1);
19846 TREE_VEC_ELT (tparms, 0)
19847 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19848 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19849 DEDUCE_CALL, LOOKUP_NORMAL,
19850 /*explain_p=*/false);
19853 if (processing_template_decl)
19854 /* Try again at instantiation time. */
19856 if (type && type != error_mark_node)
19857 /* If type is error_mark_node a diagnostic must have been
19858 emitted by now. Also, having a mention to '<type error>'
19859 in the diagnostic is not really useful to the user. */
19860 error ("unable to deduce %qT from %qE", type, init);
19861 return error_mark_node;
19864 /* If the list of declarators contains more than one declarator, the type
19865 of each declared variable is determined as described above. If the
19866 type deduced for the template parameter U is not the same in each
19867 deduction, the program is ill-formed. */
19868 if (TREE_TYPE (auto_node)
19869 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19871 error ("inconsistent deduction for %qT: %qT and then %qT",
19872 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19873 return error_mark_node;
19875 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19877 if (processing_template_decl)
19878 targs = add_to_template_args (current_template_args (), targs);
19879 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19882 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19886 splice_late_return_type (tree type, tree late_return_type)
19890 if (late_return_type == NULL_TREE)
19892 argvec = make_tree_vec (1);
19893 TREE_VEC_ELT (argvec, 0) = late_return_type;
19894 if (processing_template_parmlist)
19895 /* For a late-specified return type in a template type-parameter, we
19896 need to add a dummy argument level for its parmlist. */
19897 argvec = add_to_template_args
19898 (make_tree_vec (processing_template_parmlist), argvec);
19899 if (current_template_parms)
19900 argvec = add_to_template_args (current_template_args (), argvec);
19901 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19904 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19907 is_auto (const_tree type)
19909 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19910 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
19916 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
19917 appear as a type-specifier for the declaration in question, we don't
19918 have to look through the whole type. */
19921 type_uses_auto (tree type)
19923 enum tree_code code;
19924 if (is_auto (type))
19927 code = TREE_CODE (type);
19929 if (code == POINTER_TYPE || code == REFERENCE_TYPE
19930 || code == OFFSET_TYPE || code == FUNCTION_TYPE
19931 || code == METHOD_TYPE || code == ARRAY_TYPE)
19932 return type_uses_auto (TREE_TYPE (type));
19934 if (TYPE_PTRMEMFUNC_P (type))
19935 return type_uses_auto (TREE_TYPE (TREE_TYPE
19936 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
19941 /* For a given template T, return the vector of typedefs referenced
19942 in T for which access check is needed at T instantiation time.
19943 T is either a FUNCTION_DECL or a RECORD_TYPE.
19944 Those typedefs were added to T by the function
19945 append_type_to_template_for_access_check. */
19947 VEC(qualified_typedef_usage_t,gc)*
19948 get_types_needing_access_check (tree t)
19951 VEC(qualified_typedef_usage_t,gc) *result = NULL;
19953 if (!t || t == error_mark_node)
19956 if (!(ti = get_template_info (t)))
19959 if (CLASS_TYPE_P (t)
19960 || TREE_CODE (t) == FUNCTION_DECL)
19962 if (!TI_TEMPLATE (ti))
19965 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
19971 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
19972 tied to T. That list of typedefs will be access checked at
19973 T instantiation time.
19974 T is either a FUNCTION_DECL or a RECORD_TYPE.
19975 TYPE_DECL is a TYPE_DECL node representing a typedef.
19976 SCOPE is the scope through which TYPE_DECL is accessed.
19977 LOCATION is the location of the usage point of TYPE_DECL.
19979 This function is a subroutine of
19980 append_type_to_template_for_access_check. */
19983 append_type_to_template_for_access_check_1 (tree t,
19986 location_t location)
19988 qualified_typedef_usage_t typedef_usage;
19991 if (!t || t == error_mark_node)
19994 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
19995 || CLASS_TYPE_P (t))
19997 && TREE_CODE (type_decl) == TYPE_DECL
20000 if (!(ti = get_template_info (t)))
20003 gcc_assert (TI_TEMPLATE (ti));
20005 typedef_usage.typedef_decl = type_decl;
20006 typedef_usage.context = scope;
20007 typedef_usage.locus = location;
20009 VEC_safe_push (qualified_typedef_usage_t, gc,
20010 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20014 /* Append TYPE_DECL to the template TEMPL.
20015 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20016 At TEMPL instanciation time, TYPE_DECL will be checked to see
20017 if it can be accessed through SCOPE.
20018 LOCATION is the location of the usage point of TYPE_DECL.
20020 e.g. consider the following code snippet:
20027 template<class U> struct S
20029 C::myint mi; // <-- usage point of the typedef C::myint
20034 At S<char> instantiation time, we need to check the access of C::myint
20035 In other words, we need to check the access of the myint typedef through
20036 the C scope. For that purpose, this function will add the myint typedef
20037 and the scope C through which its being accessed to a list of typedefs
20038 tied to the template S. That list will be walked at template instantiation
20039 time and access check performed on each typedefs it contains.
20040 Note that this particular code snippet should yield an error because
20041 myint is private to C. */
20044 append_type_to_template_for_access_check (tree templ,
20047 location_t location)
20049 qualified_typedef_usage_t *iter;
20052 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20054 /* Make sure we don't append the type to the template twice. */
20055 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20056 get_types_needing_access_check (templ),
20058 if (iter->typedef_decl == type_decl && scope == iter->context)
20061 append_type_to_template_for_access_check_1 (templ, type_decl,
20065 /* Set up the hash tables for template instantiations. */
20068 init_template_processing (void)
20070 decl_specializations = htab_create_ggc (37,
20071 hash_specialization,
20072 eq_specializations,
20074 type_specializations = htab_create_ggc (37,
20075 hash_specialization,
20076 eq_specializations,
20080 /* Print stats about the template hash tables for -fstats. */
20083 print_template_statistics (void)
20085 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20086 "%f collisions\n", (long) htab_size (decl_specializations),
20087 (long) htab_elements (decl_specializations),
20088 htab_collisions (decl_specializations));
20089 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20090 "%f collisions\n", (long) htab_size (type_specializations),
20091 (long) htab_elements (type_specializations),
20092 htab_collisions (type_specializations));
20095 #include "gt-cp-pt.h"