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, unification_kind_t, 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 bool arg_from_parm_pack_p (tree, tree);
207 static tree current_template_args (void);
208 static tree fixup_template_type_parm_type (tree, int);
209 static tree fixup_template_parm_index (tree, tree, int);
210 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
212 /* Make the current scope suitable for access checking when we are
213 processing T. T can be FUNCTION_DECL for instantiated function
214 template, or VAR_DECL for static member variable (need by
215 instantiate_decl). */
218 push_access_scope (tree t)
220 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
221 || TREE_CODE (t) == VAR_DECL);
223 if (DECL_FRIEND_CONTEXT (t))
224 push_nested_class (DECL_FRIEND_CONTEXT (t));
225 else if (DECL_CLASS_SCOPE_P (t))
226 push_nested_class (DECL_CONTEXT (t));
228 push_to_top_level ();
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 saved_access_scope = tree_cons
233 (NULL_TREE, current_function_decl, saved_access_scope);
234 current_function_decl = t;
238 /* Restore the scope set up by push_access_scope. T is the node we
242 pop_access_scope (tree t)
244 if (TREE_CODE (t) == FUNCTION_DECL)
246 current_function_decl = TREE_VALUE (saved_access_scope);
247 saved_access_scope = TREE_CHAIN (saved_access_scope);
250 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
253 pop_from_top_level ();
256 /* Do any processing required when DECL (a member template
257 declaration) is finished. Returns the TEMPLATE_DECL corresponding
258 to DECL, unless it is a specialization, in which case the DECL
259 itself is returned. */
262 finish_member_template_decl (tree decl)
264 if (decl == error_mark_node)
265 return error_mark_node;
267 gcc_assert (DECL_P (decl));
269 if (TREE_CODE (decl) == TYPE_DECL)
273 type = TREE_TYPE (decl);
274 if (type == error_mark_node)
275 return error_mark_node;
276 if (MAYBE_CLASS_TYPE_P (type)
277 && CLASSTYPE_TEMPLATE_INFO (type)
278 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
280 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
281 check_member_template (tmpl);
286 else if (TREE_CODE (decl) == FIELD_DECL)
287 error ("data member %qD cannot be a member template", decl);
288 else if (DECL_TEMPLATE_INFO (decl))
290 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
292 check_member_template (DECL_TI_TEMPLATE (decl));
293 return DECL_TI_TEMPLATE (decl);
299 error ("invalid member template declaration %qD", decl);
301 return error_mark_node;
304 /* Create a template info node. */
307 build_template_info (tree template_decl, tree template_args)
309 tree result = make_node (TEMPLATE_INFO);
310 TI_TEMPLATE (result) = template_decl;
311 TI_ARGS (result) = template_args;
315 /* Return the template info node corresponding to T, whatever T is. */
318 get_template_info (const_tree t)
320 tree tinfo = NULL_TREE;
322 if (!t || t == error_mark_node)
325 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
326 tinfo = DECL_TEMPLATE_INFO (t);
328 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
331 if (TAGGED_TYPE_P (t))
332 tinfo = TYPE_TEMPLATE_INFO (t);
333 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
334 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
339 /* Returns the template nesting level of the indicated class TYPE.
349 A<T>::B<U> has depth two, while A<T> has depth one.
350 Both A<T>::B<int> and A<int>::B<U> have depth one, if
351 they are instantiations, not specializations.
353 This function is guaranteed to return 0 if passed NULL_TREE so
354 that, for example, `template_class_depth (current_class_type)' is
358 template_class_depth (tree type)
363 type && TREE_CODE (type) != NAMESPACE_DECL;
364 type = (TREE_CODE (type) == FUNCTION_DECL)
365 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
367 tree tinfo = get_template_info (type);
369 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
370 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
377 /* Subroutine of maybe_begin_member_template_processing.
378 Returns true if processing DECL needs us to push template parms. */
381 inline_needs_template_parms (tree decl)
383 if (! DECL_TEMPLATE_INFO (decl))
386 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
387 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
390 /* Subroutine of maybe_begin_member_template_processing.
391 Push the template parms in PARMS, starting from LEVELS steps into the
392 chain, and ending at the beginning, since template parms are listed
396 push_inline_template_parms_recursive (tree parmlist, int levels)
398 tree parms = TREE_VALUE (parmlist);
402 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
404 ++processing_template_decl;
405 current_template_parms
406 = tree_cons (size_int (processing_template_decl),
407 parms, current_template_parms);
408 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
410 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
412 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
414 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
416 if (parm == error_mark_node)
419 gcc_assert (DECL_P (parm));
421 switch (TREE_CODE (parm))
430 /* Make a CONST_DECL as is done in process_template_parm.
431 It is ugly that we recreate this here; the original
432 version built in process_template_parm is no longer
434 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
435 CONST_DECL, DECL_NAME (parm),
437 DECL_ARTIFICIAL (decl) = 1;
438 TREE_CONSTANT (decl) = 1;
439 TREE_READONLY (decl) = 1;
440 DECL_INITIAL (decl) = DECL_INITIAL (parm);
441 SET_DECL_TEMPLATE_PARM_P (decl);
452 /* Restore the template parameter context for a member template or
453 a friend template defined in a class definition. */
456 maybe_begin_member_template_processing (tree decl)
461 if (inline_needs_template_parms (decl))
463 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
464 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
466 if (DECL_TEMPLATE_SPECIALIZATION (decl))
469 parms = TREE_CHAIN (parms);
472 push_inline_template_parms_recursive (parms, levels);
475 /* Remember how many levels of template parameters we pushed so that
476 we can pop them later. */
477 VEC_safe_push (int, heap, inline_parm_levels, levels);
480 /* Undo the effects of maybe_begin_member_template_processing. */
483 maybe_end_member_template_processing (void)
488 if (VEC_length (int, inline_parm_levels) == 0)
491 last = VEC_pop (int, inline_parm_levels);
492 for (i = 0; i < last; ++i)
494 --processing_template_decl;
495 current_template_parms = TREE_CHAIN (current_template_parms);
500 /* Return a new template argument vector which contains all of ARGS,
501 but has as its innermost set of arguments the EXTRA_ARGS. */
504 add_to_template_args (tree args, tree extra_args)
511 if (args == NULL_TREE || extra_args == error_mark_node)
514 extra_depth = TMPL_ARGS_DEPTH (extra_args);
515 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
517 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
518 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
520 for (j = 1; j <= extra_depth; ++j, ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
526 /* Like add_to_template_args, but only the outermost ARGS are added to
527 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
528 (EXTRA_ARGS) levels are added. This function is used to combine
529 the template arguments from a partial instantiation with the
530 template arguments used to attain the full instantiation from the
531 partial instantiation. */
534 add_outermost_template_args (tree args, tree extra_args)
538 /* If there are more levels of EXTRA_ARGS than there are ARGS,
539 something very fishy is going on. */
540 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
542 /* If *all* the new arguments will be the EXTRA_ARGS, just return
544 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
547 /* For the moment, we make ARGS look like it contains fewer levels. */
548 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
550 new_args = add_to_template_args (args, extra_args);
552 /* Now, we restore ARGS to its full dimensions. */
553 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
558 /* Return the N levels of innermost template arguments from the ARGS. */
561 get_innermost_template_args (tree args, int n)
569 /* If N is 1, just return the innermost set of template arguments. */
571 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
573 /* If we're not removing anything, just return the arguments we were
575 extra_levels = TMPL_ARGS_DEPTH (args) - n;
576 gcc_assert (extra_levels >= 0);
577 if (extra_levels == 0)
580 /* Make a new set of arguments, not containing the outer arguments. */
581 new_args = make_tree_vec (n);
582 for (i = 1; i <= n; ++i)
583 SET_TMPL_ARGS_LEVEL (new_args, i,
584 TMPL_ARGS_LEVEL (args, i + extra_levels));
589 /* The inverse of get_innermost_template_args: Return all but the innermost
590 EXTRA_LEVELS levels of template arguments from the ARGS. */
593 strip_innermost_template_args (tree args, int extra_levels)
596 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
601 /* If N is 1, just return the outermost set of template arguments. */
603 return TMPL_ARGS_LEVEL (args, 1);
605 /* If we're not removing anything, just return the arguments we were
607 gcc_assert (extra_levels >= 0);
608 if (extra_levels == 0)
611 /* Make a new set of arguments, not containing the inner arguments. */
612 new_args = make_tree_vec (n);
613 for (i = 1; i <= n; ++i)
614 SET_TMPL_ARGS_LEVEL (new_args, i,
615 TMPL_ARGS_LEVEL (args, i));
620 /* We've got a template header coming up; push to a new level for storing
624 begin_template_parm_list (void)
626 /* We use a non-tag-transparent scope here, which causes pushtag to
627 put tags in this scope, rather than in the enclosing class or
628 namespace scope. This is the right thing, since we want
629 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
630 global template class, push_template_decl handles putting the
631 TEMPLATE_DECL into top-level scope. For a nested template class,
634 template <class T> struct S1 {
635 template <class T> struct S2 {};
638 pushtag contains special code to call pushdecl_with_scope on the
639 TEMPLATE_DECL for S2. */
640 begin_scope (sk_template_parms, NULL);
641 ++processing_template_decl;
642 ++processing_template_parmlist;
643 note_template_header (0);
646 /* This routine is called when a specialization is declared. If it is
647 invalid to declare a specialization here, an error is reported and
648 false is returned, otherwise this routine will return true. */
651 check_specialization_scope (void)
653 tree scope = current_scope ();
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template
664 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
666 error ("explicit specialization in non-namespace scope %qD", scope);
672 In an explicit specialization declaration for a member of a class
673 template or a member template that appears in namespace scope,
674 the member template and some of its enclosing class templates may
675 remain unspecialized, except that the declaration shall not
676 explicitly specialize a class member template if its enclosing
677 class templates are not explicitly specialized as well. */
678 if (current_template_parms)
680 error ("enclosing class templates are not explicitly specialized");
687 /* We've just seen template <>. */
690 begin_specialization (void)
692 begin_scope (sk_template_spec, NULL);
693 note_template_header (1);
694 return check_specialization_scope ();
697 /* Called at then end of processing a declaration preceded by
701 end_specialization (void)
704 reset_specialization ();
707 /* Any template <>'s that we have seen thus far are not referring to a
708 function specialization. */
711 reset_specialization (void)
713 processing_specialization = 0;
714 template_header_count = 0;
717 /* We've just seen a template header. If SPECIALIZATION is nonzero,
718 it was of the form template <>. */
721 note_template_header (int specialization)
723 processing_specialization = specialization;
724 template_header_count++;
727 /* We're beginning an explicit instantiation. */
730 begin_explicit_instantiation (void)
732 gcc_assert (!processing_explicit_instantiation);
733 processing_explicit_instantiation = true;
738 end_explicit_instantiation (void)
740 gcc_assert (processing_explicit_instantiation);
741 processing_explicit_instantiation = false;
744 /* An explicit specialization or partial specialization TMPL is being
745 declared. Check that the namespace in which the specialization is
746 occurring is permissible. Returns false iff it is invalid to
747 specialize TMPL in the current namespace. */
750 check_specialization_namespace (tree tmpl)
752 tree tpl_ns = decl_namespace_context (tmpl);
756 An explicit specialization shall be declared in the namespace of
757 which the template is a member, or, for member templates, in the
758 namespace of which the enclosing class or enclosing class
759 template is a member. An explicit specialization of a member
760 function, member class or static data member of a class template
761 shall be declared in the namespace of which the class template is
763 if (current_scope() != DECL_CONTEXT (tmpl)
764 && !at_namespace_scope_p ())
766 error ("specialization of %qD must appear at namespace scope", tmpl);
769 if (is_associated_namespace (current_namespace, tpl_ns))
770 /* Same or super-using namespace. */
774 permerror (input_location, "specialization of %qD in different namespace", tmpl);
775 permerror (input_location, " from definition of %q+#D", tmpl);
780 /* SPEC is an explicit instantiation. Check that it is valid to
781 perform this explicit instantiation in the current namespace. */
784 check_explicit_instantiation_namespace (tree spec)
788 /* DR 275: An explicit instantiation shall appear in an enclosing
789 namespace of its template. */
790 ns = decl_namespace_context (spec);
791 if (!is_ancestor (current_namespace, ns))
792 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
793 "(which does not enclose namespace %qD)",
794 spec, current_namespace, ns);
797 /* The TYPE is being declared. If it is a template type, that means it
798 is a partial specialization. Do appropriate error-checking. */
801 maybe_process_partial_specialization (tree type)
805 if (type == error_mark_node)
806 return error_mark_node;
808 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
810 error ("name of class shadows template template parameter %qD",
812 return error_mark_node;
815 context = TYPE_CONTEXT (type);
817 if ((CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
818 /* Consider non-class instantiations of alias templates as
821 && TYPE_TEMPLATE_INFO (type)
822 && DECL_LANG_SPECIFIC (TYPE_NAME (type))
823 && DECL_USE_TEMPLATE (TYPE_NAME (type))))
825 /* This is for ordinary explicit specialization and partial
826 specialization of a template class such as:
828 template <> class C<int>;
832 template <class T> class C<T*>;
834 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
836 if (CLASS_TYPE_P (type)
837 && CLASSTYPE_IMPLICIT_INSTANTIATION (type)
838 && !COMPLETE_TYPE_P (type))
840 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
841 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
842 if (processing_template_decl)
844 if (push_template_decl (TYPE_MAIN_DECL (type))
846 return error_mark_node;
849 else if (CLASS_TYPE_P (type)
850 && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
851 error ("specialization of %qT after instantiation", type);
853 if (DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (type)))
855 error ("partial specialization of alias template %qD",
856 TYPE_TI_TEMPLATE (type));
857 return error_mark_node;
860 else if (CLASS_TYPE_P (type)
861 && !CLASSTYPE_USE_TEMPLATE (type)
862 && CLASSTYPE_TEMPLATE_INFO (type)
863 && context && CLASS_TYPE_P (context)
864 && CLASSTYPE_TEMPLATE_INFO (context))
866 /* This is for an explicit specialization of member class
867 template according to [temp.expl.spec/18]:
869 template <> template <class U> class C<int>::D;
871 The context `C<int>' must be an implicit instantiation.
872 Otherwise this is just a member class template declared
875 template <> class C<int> { template <class U> class D; };
876 template <> template <class U> class C<int>::D;
878 In the first case, `C<int>::D' is a specialization of `C<T>::D'
879 while in the second case, `C<int>::D' is a primary template
880 and `C<T>::D' may not exist. */
882 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
883 && !COMPLETE_TYPE_P (type))
886 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
888 if (current_namespace
889 != decl_namespace_context (tmpl))
891 permerror (input_location, "specializing %q#T in different namespace", type);
892 permerror (input_location, " from definition of %q+#D", tmpl);
895 /* Check for invalid specialization after instantiation:
897 template <> template <> class C<int>::D<int>;
898 template <> template <class U> class C<int>::D; */
900 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
901 t; t = TREE_CHAIN (t))
903 tree inst = TREE_VALUE (t);
904 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
906 /* We already have a full specialization of this partial
907 instantiation. Reassign it to the new member
908 specialization template. */
913 elt.tmpl = most_general_template (tmpl);
914 elt.args = CLASSTYPE_TI_ARGS (inst);
917 htab_remove_elt (type_specializations, &elt);
920 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
922 slot = htab_find_slot (type_specializations, &elt, INSERT);
923 entry = ggc_alloc_spec_entry ();
927 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
928 /* But if we've had an implicit instantiation, that's a
929 problem ([temp.expl.spec]/6). */
930 error ("specialization %qT after instantiation %qT",
934 /* Mark TYPE as a specialization. And as a result, we only
935 have one level of template argument for the innermost
937 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
938 CLASSTYPE_TI_ARGS (type)
939 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
942 else if (processing_specialization)
944 /* Someday C++0x may allow for enum template specialization. */
945 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
946 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
947 pedwarn (input_location, OPT_pedantic, "template specialization "
948 "of %qD not allowed by ISO C++", type);
951 error ("explicit specialization of non-template %qT", type);
952 return error_mark_node;
959 /* Returns nonzero if we can optimize the retrieval of specializations
960 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
961 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
964 optimize_specialization_lookup_p (tree tmpl)
966 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
967 && DECL_CLASS_SCOPE_P (tmpl)
968 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
970 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
971 /* The optimized lookup depends on the fact that the
972 template arguments for the member function template apply
973 purely to the containing class, which is not true if the
974 containing class is an explicit or partial
976 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
977 && !DECL_MEMBER_TEMPLATE_P (tmpl)
978 && !DECL_CONV_FN_P (tmpl)
979 /* It is possible to have a template that is not a member
980 template and is not a member of a template class:
982 template <typename T>
983 struct S { friend A::f(); };
985 Here, the friend function is a template, but the context does
986 not have template information. The optimized lookup relies
987 on having ARGS be the template arguments for both the class
988 and the function template. */
989 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
992 /* Retrieve the specialization (in the sense of [temp.spec] - a
993 specialization is either an instantiation or an explicit
994 specialization) of TMPL for the given template ARGS. If there is
995 no such specialization, return NULL_TREE. The ARGS are a vector of
996 arguments, or a vector of vectors of arguments, in the case of
997 templates with more than one level of parameters.
999 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
1000 then we search for a partial specialization matching ARGS. This
1001 parameter is ignored if TMPL is not a class template. */
1004 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
1006 if (args == error_mark_node)
1009 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1011 /* There should be as many levels of arguments as there are
1012 levels of parameters. */
1013 gcc_assert (TMPL_ARGS_DEPTH (args)
1014 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1016 if (optimize_specialization_lookup_p (tmpl))
1018 tree class_template;
1019 tree class_specialization;
1020 VEC(tree,gc) *methods;
1024 /* The template arguments actually apply to the containing
1025 class. Find the class specialization with those
1027 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1028 class_specialization
1029 = retrieve_specialization (class_template, args, 0);
1030 if (!class_specialization)
1032 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1033 for the specialization. */
1034 idx = class_method_index_for_fn (class_specialization, tmpl);
1037 /* Iterate through the methods with the indicated name, looking
1038 for the one that has an instance of TMPL. */
1039 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1040 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1042 tree fn = OVL_CURRENT (fns);
1043 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1044 /* using-declarations can add base methods to the method vec,
1045 and we don't want those here. */
1046 && DECL_CONTEXT (fn) == class_specialization)
1055 htab_t specializations;
1059 elt.spec = NULL_TREE;
1061 if (DECL_CLASS_TEMPLATE_P (tmpl))
1062 specializations = type_specializations;
1064 specializations = decl_specializations;
1067 hash = hash_specialization (&elt);
1068 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1076 /* Like retrieve_specialization, but for local declarations. */
1079 retrieve_local_specialization (tree tmpl)
1083 if (local_specializations == NULL)
1086 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1087 htab_hash_pointer (tmpl));
1088 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1091 /* Returns nonzero iff DECL is a specialization of TMPL. */
1094 is_specialization_of (tree decl, tree tmpl)
1098 if (TREE_CODE (decl) == FUNCTION_DECL)
1102 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1108 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1110 for (t = TREE_TYPE (decl);
1112 t = CLASSTYPE_USE_TEMPLATE (t)
1113 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1114 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1121 /* Returns nonzero iff DECL is a specialization of friend declaration
1122 FRIEND_DECL according to [temp.friend]. */
1125 is_specialization_of_friend (tree decl, tree friend_decl)
1127 bool need_template = true;
1130 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1131 || TREE_CODE (decl) == TYPE_DECL);
1133 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1134 of a template class, we want to check if DECL is a specialization
1136 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1137 && DECL_TEMPLATE_INFO (friend_decl)
1138 && !DECL_USE_TEMPLATE (friend_decl))
1140 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1141 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1142 need_template = false;
1144 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1145 && !PRIMARY_TEMPLATE_P (friend_decl))
1146 need_template = false;
1148 /* There is nothing to do if this is not a template friend. */
1149 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1152 if (is_specialization_of (decl, friend_decl))
1156 A member of a class template may be declared to be a friend of a
1157 non-template class. In this case, the corresponding member of
1158 every specialization of the class template is a friend of the
1159 class granting friendship.
1161 For example, given a template friend declaration
1163 template <class T> friend void A<T>::f();
1165 the member function below is considered a friend
1167 template <> struct A<int> {
1171 For this type of template friend, TEMPLATE_DEPTH below will be
1172 nonzero. To determine if DECL is a friend of FRIEND, we first
1173 check if the enclosing class is a specialization of another. */
1175 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1177 && DECL_CLASS_SCOPE_P (decl)
1178 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1179 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1181 /* Next, we check the members themselves. In order to handle
1182 a few tricky cases, such as when FRIEND_DECL's are
1184 template <class T> friend void A<T>::g(T t);
1185 template <class T> template <T t> friend void A<T>::h();
1189 void A<int>::g(int);
1190 template <int> void A<int>::h();
1192 we need to figure out ARGS, the template arguments from
1193 the context of DECL. This is required for template substitution
1194 of `T' in the function parameter of `g' and template parameter
1195 of `h' in the above examples. Here ARGS corresponds to `int'. */
1197 tree context = DECL_CONTEXT (decl);
1198 tree args = NULL_TREE;
1199 int current_depth = 0;
1201 while (current_depth < template_depth)
1203 if (CLASSTYPE_TEMPLATE_INFO (context))
1205 if (current_depth == 0)
1206 args = TYPE_TI_ARGS (context);
1208 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1211 context = TYPE_CONTEXT (context);
1214 if (TREE_CODE (decl) == FUNCTION_DECL)
1219 tree friend_args_type;
1220 tree decl_args_type;
1222 /* Make sure that both DECL and FRIEND_DECL are templates or
1224 is_template = DECL_TEMPLATE_INFO (decl)
1225 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1226 if (need_template ^ is_template)
1228 else if (is_template)
1230 /* If both are templates, check template parameter list. */
1232 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1234 if (!comp_template_parms
1235 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1239 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1242 decl_type = TREE_TYPE (decl);
1244 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1245 tf_none, NULL_TREE);
1246 if (friend_type == error_mark_node)
1249 /* Check if return types match. */
1250 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1253 /* Check if function parameter types match, ignoring the
1254 `this' parameter. */
1255 friend_args_type = TYPE_ARG_TYPES (friend_type);
1256 decl_args_type = TYPE_ARG_TYPES (decl_type);
1257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1258 friend_args_type = TREE_CHAIN (friend_args_type);
1259 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1260 decl_args_type = TREE_CHAIN (decl_args_type);
1262 return compparms (decl_args_type, friend_args_type);
1266 /* DECL is a TYPE_DECL */
1268 tree decl_type = TREE_TYPE (decl);
1270 /* Make sure that both DECL and FRIEND_DECL are templates or
1273 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1274 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1276 if (need_template ^ is_template)
1278 else if (is_template)
1281 /* If both are templates, check the name of the two
1282 TEMPLATE_DECL's first because is_friend didn't. */
1283 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1284 != DECL_NAME (friend_decl))
1287 /* Now check template parameter list. */
1289 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1291 return comp_template_parms
1292 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1296 return (DECL_NAME (decl)
1297 == DECL_NAME (friend_decl));
1303 /* Register the specialization SPEC as a specialization of TMPL with
1304 the indicated ARGS. IS_FRIEND indicates whether the specialization
1305 is actually just a friend declaration. Returns SPEC, or an
1306 equivalent prior declaration, if available. */
1309 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1316 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1318 if (TREE_CODE (spec) == FUNCTION_DECL
1319 && uses_template_parms (DECL_TI_ARGS (spec)))
1320 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1321 register it; we want the corresponding TEMPLATE_DECL instead.
1322 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1323 the more obvious `uses_template_parms (spec)' to avoid problems
1324 with default function arguments. In particular, given
1325 something like this:
1327 template <class T> void f(T t1, T t = T())
1329 the default argument expression is not substituted for in an
1330 instantiation unless and until it is actually needed. */
1333 if (optimize_specialization_lookup_p (tmpl))
1334 /* We don't put these specializations in the hash table, but we might
1335 want to give an error about a mismatch. */
1336 fn = retrieve_specialization (tmpl, args, 0);
1344 hash = hash_specialization (&elt);
1347 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1349 fn = ((spec_entry *) *slot)->spec;
1354 /* We can sometimes try to re-register a specialization that we've
1355 already got. In particular, regenerate_decl_from_template calls
1356 duplicate_decls which will update the specialization list. But,
1357 we'll still get called again here anyhow. It's more convenient
1358 to simply allow this than to try to prevent it. */
1361 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1363 if (DECL_TEMPLATE_INSTANTIATION (fn))
1365 if (DECL_ODR_USED (fn)
1366 || DECL_EXPLICIT_INSTANTIATION (fn))
1368 error ("specialization of %qD after instantiation",
1370 return error_mark_node;
1375 /* This situation should occur only if the first
1376 specialization is an implicit instantiation, the
1377 second is an explicit specialization, and the
1378 implicit instantiation has not yet been used. That
1379 situation can occur if we have implicitly
1380 instantiated a member function and then specialized
1383 We can also wind up here if a friend declaration that
1384 looked like an instantiation turns out to be a
1387 template <class T> void foo(T);
1388 class S { friend void foo<>(int) };
1389 template <> void foo(int);
1391 We transform the existing DECL in place so that any
1392 pointers to it become pointers to the updated
1395 If there was a definition for the template, but not
1396 for the specialization, we want this to look as if
1397 there were no definition, and vice versa. */
1398 DECL_INITIAL (fn) = NULL_TREE;
1399 duplicate_decls (spec, fn, is_friend);
1400 /* The call to duplicate_decls will have applied
1403 An explicit specialization of a function template
1404 is inline only if it is explicitly declared to be,
1405 and independently of whether its function template
1408 to the primary function; now copy the inline bits to
1409 the various clones. */
1410 FOR_EACH_CLONE (clone, fn)
1412 DECL_DECLARED_INLINE_P (clone)
1413 = DECL_DECLARED_INLINE_P (fn);
1414 DECL_SOURCE_LOCATION (clone)
1415 = DECL_SOURCE_LOCATION (fn);
1417 check_specialization_namespace (fn);
1422 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1424 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1425 /* Dup decl failed, but this is a new definition. Set the
1426 line number so any errors match this new
1428 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1434 return duplicate_decls (spec, fn, is_friend);
1436 /* A specialization must be declared in the same namespace as the
1437 template it is specializing. */
1438 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1439 && !check_specialization_namespace (tmpl))
1440 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1442 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */)
1444 spec_entry *entry = ggc_alloc_spec_entry ();
1445 gcc_assert (tmpl && args && spec);
1448 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1449 && PRIMARY_TEMPLATE_P (tmpl)
1450 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1451 /* TMPL is a forward declaration of a template function; keep a list
1452 of all specializations in case we need to reassign them to a friend
1453 template later in tsubst_friend_function. */
1454 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1455 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1461 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1462 TMPL and ARGS members, ignores SPEC. */
1465 eq_specializations (const void *p1, const void *p2)
1467 const spec_entry *e1 = (const spec_entry *)p1;
1468 const spec_entry *e2 = (const spec_entry *)p2;
1470 return (e1->tmpl == e2->tmpl
1471 && comp_template_args (e1->args, e2->args));
1474 /* Returns a hash for a template TMPL and template arguments ARGS. */
1477 hash_tmpl_and_args (tree tmpl, tree args)
1479 hashval_t val = DECL_UID (tmpl);
1480 return iterative_hash_template_arg (args, val);
1483 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1487 hash_specialization (const void *p)
1489 const spec_entry *e = (const spec_entry *)p;
1490 return hash_tmpl_and_args (e->tmpl, e->args);
1493 /* Recursively calculate a hash value for a template argument ARG, for use
1494 in the hash tables of template specializations. */
1497 iterative_hash_template_arg (tree arg, hashval_t val)
1499 unsigned HOST_WIDE_INT i;
1500 enum tree_code code;
1503 if (arg == NULL_TREE)
1504 return iterative_hash_object (arg, val);
1509 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1510 /* We can get one of these when re-hashing a previous entry in the middle
1511 of substituting into a pack expansion. Just look through it. */
1512 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1514 code = TREE_CODE (arg);
1515 tclass = TREE_CODE_CLASS (code);
1517 val = iterative_hash_object (code, val);
1524 case IDENTIFIER_NODE:
1525 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1529 int i, len = TREE_VEC_LENGTH (arg);
1530 for (i = 0; i < len; ++i)
1531 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1535 case TYPE_PACK_EXPANSION:
1536 case EXPR_PACK_EXPANSION:
1537 val = iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1538 return iterative_hash_template_arg (PACK_EXPANSION_EXTRA_ARGS (arg), val);
1540 case TYPE_ARGUMENT_PACK:
1541 case NONTYPE_ARGUMENT_PACK:
1542 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1545 for (; arg; arg = TREE_CHAIN (arg))
1546 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1550 for (; arg; arg = OVL_NEXT (arg))
1551 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1557 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1559 val = iterative_hash_template_arg (field, val);
1560 val = iterative_hash_template_arg (value, val);
1566 if (!DECL_ARTIFICIAL (arg))
1568 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1569 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1571 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1574 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1577 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1578 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1580 case TEMPLATE_PARM_INDEX:
1581 val = iterative_hash_template_arg
1582 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1583 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1584 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1587 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1588 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1589 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1592 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1594 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1598 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1599 code = TREE_CODE (TREE_OPERAND (arg, 1));
1600 val = iterative_hash_object (code, val);
1601 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1604 /* A lambda can't appear in a template arg, but don't crash on
1606 gcc_assert (seen_error ());
1610 case IMPLICIT_CONV_EXPR:
1611 case STATIC_CAST_EXPR:
1612 case REINTERPRET_CAST_EXPR:
1613 case CONST_CAST_EXPR:
1614 case DYNAMIC_CAST_EXPR:
1616 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1617 /* Now hash operands as usual. */
1627 if (TYPE_CANONICAL (arg))
1628 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1630 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1631 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1632 /* Otherwise just compare the types during lookup. */
1635 case tcc_declaration:
1637 return iterative_hash_expr (arg, val);
1640 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1642 unsigned n = cp_tree_operand_length (arg);
1643 for (i = 0; i < n; ++i)
1644 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1652 /* Unregister the specialization SPEC as a specialization of TMPL.
1653 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1654 if the SPEC was listed as a specialization of TMPL.
1656 Note that SPEC has been ggc_freed, so we can't look inside it. */
1659 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1664 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1665 elt.args = TI_ARGS (tinfo);
1666 elt.spec = NULL_TREE;
1668 entry = (spec_entry *) htab_find (decl_specializations, &elt);
1671 gcc_assert (entry->spec == spec || entry->spec == new_spec);
1672 gcc_assert (new_spec != NULL_TREE);
1673 entry->spec = new_spec;
1680 /* Compare an entry in the local specializations hash table P1 (which
1681 is really a pointer to a TREE_LIST) with P2 (which is really a
1685 eq_local_specializations (const void *p1, const void *p2)
1687 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1690 /* Hash P1, an entry in the local specializations table. */
1693 hash_local_specialization (const void* p1)
1695 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1698 /* Like register_specialization, but for local declarations. We are
1699 registering SPEC, an instantiation of TMPL. */
1702 register_local_specialization (tree spec, tree tmpl)
1706 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1707 htab_hash_pointer (tmpl), INSERT);
1708 *slot = build_tree_list (spec, tmpl);
1711 /* TYPE is a class type. Returns true if TYPE is an explicitly
1712 specialized class. */
1715 explicit_class_specialization_p (tree type)
1717 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1719 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1722 /* Print the list of functions at FNS, going through all the overloads
1723 for each element of the list. Alternatively, FNS can not be a
1724 TREE_LIST, in which case it will be printed together with all the
1727 MORE and *STR should respectively be FALSE and NULL when the function
1728 is called from the outside. They are used internally on recursive
1729 calls. print_candidates manages the two parameters and leaves NULL
1730 in *STR when it ends. */
1733 print_candidates_1 (tree fns, bool more, const char **str)
1736 char *spaces = NULL;
1738 for (fn = fns; fn; fn = OVL_NEXT (fn))
1739 if (TREE_CODE (fn) == TREE_LIST)
1741 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1742 print_candidates_1 (TREE_VALUE (fn2),
1743 TREE_CHAIN (fn2) || more, str);
1749 /* Pick the prefix string. */
1750 if (!more && !OVL_NEXT (fns))
1752 error ("candidate is: %+#D", OVL_CURRENT (fn));
1756 *str = _("candidates are:");
1757 spaces = get_spaces (*str);
1759 error ("%s %+#D", *str, OVL_CURRENT (fn));
1760 *str = spaces ? spaces : *str;
1770 /* Print the list of candidate FNS in an error message. FNS can also
1771 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1774 print_candidates (tree fns)
1776 const char *str = NULL;
1777 print_candidates_1 (fns, false, &str);
1778 gcc_assert (str == NULL);
1781 /* Returns the template (one of the functions given by TEMPLATE_ID)
1782 which can be specialized to match the indicated DECL with the
1783 explicit template args given in TEMPLATE_ID. The DECL may be
1784 NULL_TREE if none is available. In that case, the functions in
1785 TEMPLATE_ID are non-members.
1787 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1788 specialization of a member template.
1790 The TEMPLATE_COUNT is the number of references to qualifying
1791 template classes that appeared in the name of the function. See
1792 check_explicit_specialization for a more accurate description.
1794 TSK indicates what kind of template declaration (if any) is being
1795 declared. TSK_TEMPLATE indicates that the declaration given by
1796 DECL, though a FUNCTION_DECL, has template parameters, and is
1797 therefore a template function.
1799 The template args (those explicitly specified and those deduced)
1800 are output in a newly created vector *TARGS_OUT.
1802 If it is impossible to determine the result, an error message is
1803 issued. The error_mark_node is returned to indicate failure. */
1806 determine_specialization (tree template_id,
1809 int need_member_template,
1815 tree explicit_targs;
1816 tree candidates = NULL_TREE;
1817 /* A TREE_LIST of templates of which DECL may be a specialization.
1818 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1819 corresponding TREE_PURPOSE is the set of template arguments that,
1820 when used to instantiate the template, would produce a function
1821 with the signature of DECL. */
1822 tree templates = NULL_TREE;
1824 cp_binding_level *b;
1826 *targs_out = NULL_TREE;
1828 if (template_id == error_mark_node || decl == error_mark_node)
1829 return error_mark_node;
1831 fns = TREE_OPERAND (template_id, 0);
1832 explicit_targs = TREE_OPERAND (template_id, 1);
1834 if (fns == error_mark_node)
1835 return error_mark_node;
1837 /* Check for baselinks. */
1838 if (BASELINK_P (fns))
1839 fns = BASELINK_FUNCTIONS (fns);
1841 if (!is_overloaded_fn (fns))
1843 error ("%qD is not a function template", fns);
1844 return error_mark_node;
1847 /* Count the number of template headers specified for this
1850 for (b = current_binding_level;
1851 b->kind == sk_template_parms;
1855 for (; fns; fns = OVL_NEXT (fns))
1857 tree fn = OVL_CURRENT (fns);
1859 if (TREE_CODE (fn) == TEMPLATE_DECL)
1861 tree decl_arg_types;
1864 /* In case of explicit specialization, we need to check if
1865 the number of template headers appearing in the specialization
1866 is correct. This is usually done in check_explicit_specialization,
1867 but the check done there cannot be exhaustive when specializing
1868 member functions. Consider the following code:
1870 template <> void A<int>::f(int);
1871 template <> template <> void A<int>::f(int);
1873 Assuming that A<int> is not itself an explicit specialization
1874 already, the first line specializes "f" which is a non-template
1875 member function, whilst the second line specializes "f" which
1876 is a template member function. So both lines are syntactically
1877 correct, and check_explicit_specialization does not reject
1880 Here, we can do better, as we are matching the specialization
1881 against the declarations. We count the number of template
1882 headers, and we check if they match TEMPLATE_COUNT + 1
1883 (TEMPLATE_COUNT is the number of qualifying template classes,
1884 plus there must be another header for the member template
1887 Notice that if header_count is zero, this is not a
1888 specialization but rather a template instantiation, so there
1889 is no check we can perform here. */
1890 if (header_count && header_count != template_count + 1)
1893 /* Check that the number of template arguments at the
1894 innermost level for DECL is the same as for FN. */
1895 if (current_binding_level->kind == sk_template_parms
1896 && !current_binding_level->explicit_spec_p
1897 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1898 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1899 (current_template_parms))))
1902 /* DECL might be a specialization of FN. */
1903 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1904 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1906 /* For a non-static member function, we need to make sure
1907 that the const qualification is the same. Since
1908 get_bindings does not try to merge the "this" parameter,
1909 we must do the comparison explicitly. */
1910 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1911 && !same_type_p (TREE_VALUE (fn_arg_types),
1912 TREE_VALUE (decl_arg_types)))
1915 /* Skip the "this" parameter and, for constructors of
1916 classes with virtual bases, the VTT parameter. A
1917 full specialization of a constructor will have a VTT
1918 parameter, but a template never will. */
1920 = skip_artificial_parms_for (decl, decl_arg_types);
1922 = skip_artificial_parms_for (fn, fn_arg_types);
1924 /* Check that the number of function parameters matches.
1926 template <class T> void f(int i = 0);
1927 template <> void f<int>();
1928 The specialization f<int> is invalid but is not caught
1929 by get_bindings below. */
1930 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1933 /* Function templates cannot be specializations; there are
1934 no partial specializations of functions. Therefore, if
1935 the type of DECL does not match FN, there is no
1937 if (tsk == tsk_template)
1939 if (compparms (fn_arg_types, decl_arg_types))
1940 candidates = tree_cons (NULL_TREE, fn, candidates);
1944 /* See whether this function might be a specialization of this
1946 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1949 /* We cannot deduce template arguments that when used to
1950 specialize TMPL will produce DECL. */
1953 /* Save this template, and the arguments deduced. */
1954 templates = tree_cons (targs, fn, templates);
1956 else if (need_member_template)
1957 /* FN is an ordinary member function, and we need a
1958 specialization of a member template. */
1960 else if (TREE_CODE (fn) != FUNCTION_DECL)
1961 /* We can get IDENTIFIER_NODEs here in certain erroneous
1964 else if (!DECL_FUNCTION_MEMBER_P (fn))
1965 /* This is just an ordinary non-member function. Nothing can
1966 be a specialization of that. */
1968 else if (DECL_ARTIFICIAL (fn))
1969 /* Cannot specialize functions that are created implicitly. */
1973 tree decl_arg_types;
1975 /* This is an ordinary member function. However, since
1976 we're here, we can assume it's enclosing class is a
1977 template class. For example,
1979 template <typename T> struct S { void f(); };
1980 template <> void S<int>::f() {}
1982 Here, S<int>::f is a non-template, but S<int> is a
1983 template class. If FN has the same type as DECL, we
1984 might be in business. */
1986 if (!DECL_TEMPLATE_INFO (fn))
1987 /* Its enclosing class is an explicit specialization
1988 of a template class. This is not a candidate. */
1991 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1992 TREE_TYPE (TREE_TYPE (fn))))
1993 /* The return types differ. */
1996 /* Adjust the type of DECL in case FN is a static member. */
1997 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1998 if (DECL_STATIC_FUNCTION_P (fn)
1999 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2000 decl_arg_types = TREE_CHAIN (decl_arg_types);
2002 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2005 candidates = tree_cons (NULL_TREE, fn, candidates);
2009 if (templates && TREE_CHAIN (templates))
2015 It is possible for a specialization with a given function
2016 signature to be instantiated from more than one function
2017 template. In such cases, explicit specification of the
2018 template arguments must be used to uniquely identify the
2019 function template specialization being specialized.
2021 Note that here, there's no suggestion that we're supposed to
2022 determine which of the candidate templates is most
2023 specialized. However, we, also have:
2027 Partial ordering of overloaded function template
2028 declarations is used in the following contexts to select
2029 the function template to which a function template
2030 specialization refers:
2032 -- when an explicit specialization refers to a function
2035 So, we do use the partial ordering rules, at least for now.
2036 This extension can only serve to make invalid programs valid,
2037 so it's safe. And, there is strong anecdotal evidence that
2038 the committee intended the partial ordering rules to apply;
2039 the EDG front end has that behavior, and John Spicer claims
2040 that the committee simply forgot to delete the wording in
2041 [temp.expl.spec]. */
2042 tree tmpl = most_specialized_instantiation (templates);
2043 if (tmpl != error_mark_node)
2046 TREE_CHAIN (templates) = NULL_TREE;
2050 if (templates == NULL_TREE && candidates == NULL_TREE)
2052 error ("template-id %qD for %q+D does not match any template "
2053 "declaration", template_id, decl);
2054 if (header_count && header_count != template_count + 1)
2055 inform (input_location, "saw %d %<template<>%>, need %d for "
2056 "specializing a member function template",
2057 header_count, template_count + 1);
2058 return error_mark_node;
2060 else if ((templates && TREE_CHAIN (templates))
2061 || (candidates && TREE_CHAIN (candidates))
2062 || (templates && candidates))
2064 error ("ambiguous template specialization %qD for %q+D",
2066 candidates = chainon (candidates, templates);
2067 print_candidates (candidates);
2068 return error_mark_node;
2071 /* We have one, and exactly one, match. */
2074 tree fn = TREE_VALUE (candidates);
2075 *targs_out = copy_node (DECL_TI_ARGS (fn));
2076 /* DECL is a re-declaration or partial instantiation of a template
2078 if (TREE_CODE (fn) == TEMPLATE_DECL)
2080 /* It was a specialization of an ordinary member function in a
2082 return DECL_TI_TEMPLATE (fn);
2085 /* It was a specialization of a template. */
2086 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2087 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2089 *targs_out = copy_node (targs);
2090 SET_TMPL_ARGS_LEVEL (*targs_out,
2091 TMPL_ARGS_DEPTH (*targs_out),
2092 TREE_PURPOSE (templates));
2095 *targs_out = TREE_PURPOSE (templates);
2096 return TREE_VALUE (templates);
2099 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2100 but with the default argument values filled in from those in the
2104 copy_default_args_to_explicit_spec_1 (tree spec_types,
2107 tree new_spec_types;
2112 if (spec_types == void_list_node)
2113 return void_list_node;
2115 /* Substitute into the rest of the list. */
2117 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2118 TREE_CHAIN (tmpl_types));
2120 /* Add the default argument for this parameter. */
2121 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2122 TREE_VALUE (spec_types),
2126 /* DECL is an explicit specialization. Replicate default arguments
2127 from the template it specializes. (That way, code like:
2129 template <class T> void f(T = 3);
2130 template <> void f(double);
2133 works, as required.) An alternative approach would be to look up
2134 the correct default arguments at the call-site, but this approach
2135 is consistent with how implicit instantiations are handled. */
2138 copy_default_args_to_explicit_spec (tree decl)
2143 tree new_spec_types;
2147 tree object_type = NULL_TREE;
2148 tree in_charge = NULL_TREE;
2149 tree vtt = NULL_TREE;
2151 /* See if there's anything we need to do. */
2152 tmpl = DECL_TI_TEMPLATE (decl);
2153 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2154 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2155 if (TREE_PURPOSE (t))
2160 old_type = TREE_TYPE (decl);
2161 spec_types = TYPE_ARG_TYPES (old_type);
2163 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2165 /* Remove the this pointer, but remember the object's type for
2167 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2168 spec_types = TREE_CHAIN (spec_types);
2169 tmpl_types = TREE_CHAIN (tmpl_types);
2171 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2173 /* DECL may contain more parameters than TMPL due to the extra
2174 in-charge parameter in constructors and destructors. */
2175 in_charge = spec_types;
2176 spec_types = TREE_CHAIN (spec_types);
2178 if (DECL_HAS_VTT_PARM_P (decl))
2181 spec_types = TREE_CHAIN (spec_types);
2185 /* Compute the merged default arguments. */
2187 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2189 /* Compute the new FUNCTION_TYPE. */
2193 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2198 /* Put the in-charge parameter back. */
2199 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2200 TREE_VALUE (in_charge),
2203 new_type = build_method_type_directly (object_type,
2204 TREE_TYPE (old_type),
2208 new_type = build_function_type (TREE_TYPE (old_type),
2210 new_type = cp_build_type_attribute_variant (new_type,
2211 TYPE_ATTRIBUTES (old_type));
2212 new_type = build_exception_variant (new_type,
2213 TYPE_RAISES_EXCEPTIONS (old_type));
2214 TREE_TYPE (decl) = new_type;
2217 /* Check to see if the function just declared, as indicated in
2218 DECLARATOR, and in DECL, is a specialization of a function
2219 template. We may also discover that the declaration is an explicit
2220 instantiation at this point.
2222 Returns DECL, or an equivalent declaration that should be used
2223 instead if all goes well. Issues an error message if something is
2224 amiss. Returns error_mark_node if the error is not easily
2227 FLAGS is a bitmask consisting of the following flags:
2229 2: The function has a definition.
2230 4: The function is a friend.
2232 The TEMPLATE_COUNT is the number of references to qualifying
2233 template classes that appeared in the name of the function. For
2236 template <class T> struct S { void f(); };
2239 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2240 classes are not counted in the TEMPLATE_COUNT, so that in
2242 template <class T> struct S {};
2243 template <> struct S<int> { void f(); }
2244 template <> void S<int>::f();
2246 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2247 invalid; there should be no template <>.)
2249 If the function is a specialization, it is marked as such via
2250 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2251 is set up correctly, and it is added to the list of specializations
2252 for that template. */
2255 check_explicit_specialization (tree declarator,
2260 int have_def = flags & 2;
2261 int is_friend = flags & 4;
2262 int specialization = 0;
2263 int explicit_instantiation = 0;
2264 int member_specialization = 0;
2265 tree ctype = DECL_CLASS_CONTEXT (decl);
2266 tree dname = DECL_NAME (decl);
2271 if (!processing_specialization)
2274 tsk = tsk_excessive_parms;
2277 tsk = current_tmpl_spec_kind (template_count);
2282 if (processing_specialization)
2285 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2287 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2290 /* This could be something like:
2292 template <class T> void f(T);
2293 class S { friend void f<>(int); } */
2297 /* This case handles bogus declarations like template <>
2298 template <class T> void f<int>(); */
2300 error ("template-id %qD in declaration of primary template",
2307 case tsk_invalid_member_spec:
2308 /* The error has already been reported in
2309 check_specialization_scope. */
2310 return error_mark_node;
2312 case tsk_invalid_expl_inst:
2313 error ("template parameter list used in explicit instantiation");
2319 error ("definition provided for explicit instantiation");
2321 explicit_instantiation = 1;
2324 case tsk_excessive_parms:
2325 case tsk_insufficient_parms:
2326 if (tsk == tsk_excessive_parms)
2327 error ("too many template parameter lists in declaration of %qD",
2329 else if (template_header_count)
2330 error("too few template parameter lists in declaration of %qD", decl);
2332 error("explicit specialization of %qD must be introduced by "
2333 "%<template <>%>", decl);
2337 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2339 member_specialization = 1;
2345 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2347 /* This case handles bogus declarations like template <>
2348 template <class T> void f<int>(); */
2350 if (uses_template_parms (declarator))
2351 error ("function template partial specialization %qD "
2352 "is not allowed", declarator);
2354 error ("template-id %qD in declaration of primary template",
2359 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2360 /* This is a specialization of a member template, without
2361 specialization the containing class. Something like:
2363 template <class T> struct S {
2364 template <class U> void f (U);
2366 template <> template <class U> void S<int>::f(U) {}
2368 That's a specialization -- but of the entire template. */
2376 if (specialization || member_specialization)
2378 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2379 for (; t; t = TREE_CHAIN (t))
2380 if (TREE_PURPOSE (t))
2382 permerror (input_location,
2383 "default argument specified in explicit specialization");
2388 if (specialization || member_specialization || explicit_instantiation)
2390 tree tmpl = NULL_TREE;
2391 tree targs = NULL_TREE;
2393 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2394 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2398 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2403 /* If there is no class context, the explicit instantiation
2404 must be at namespace scope. */
2405 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2407 /* Find the namespace binding, using the declaration
2409 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2411 if (fns == error_mark_node || !is_overloaded_fn (fns))
2413 error ("%qD is not a template function", dname);
2414 fns = error_mark_node;
2418 tree fn = OVL_CURRENT (fns);
2419 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2420 CP_DECL_CONTEXT (fn)))
2421 error ("%qD is not declared in %qD",
2422 decl, current_namespace);
2426 declarator = lookup_template_function (fns, NULL_TREE);
2429 if (declarator == error_mark_node)
2430 return error_mark_node;
2432 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2434 if (!explicit_instantiation)
2435 /* A specialization in class scope. This is invalid,
2436 but the error will already have been flagged by
2437 check_specialization_scope. */
2438 return error_mark_node;
2441 /* It's not valid to write an explicit instantiation in
2444 class C { template void f(); }
2446 This case is caught by the parser. However, on
2449 template class C { void f(); };
2451 (which is invalid) we can get here. The error will be
2458 else if (ctype != NULL_TREE
2459 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2462 /* Find the list of functions in ctype that have the same
2463 name as the declared function. */
2464 tree name = TREE_OPERAND (declarator, 0);
2465 tree fns = NULL_TREE;
2468 if (constructor_name_p (name, ctype))
2470 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2472 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2473 : !CLASSTYPE_DESTRUCTORS (ctype))
2475 /* From [temp.expl.spec]:
2477 If such an explicit specialization for the member
2478 of a class template names an implicitly-declared
2479 special member function (clause _special_), the
2480 program is ill-formed.
2482 Similar language is found in [temp.explicit]. */
2483 error ("specialization of implicitly-declared special member function");
2484 return error_mark_node;
2487 name = is_constructor ? ctor_identifier : dtor_identifier;
2490 if (!DECL_CONV_FN_P (decl))
2492 idx = lookup_fnfields_1 (ctype, name);
2494 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2498 VEC(tree,gc) *methods;
2501 /* For a type-conversion operator, we cannot do a
2502 name-based lookup. We might be looking for `operator
2503 int' which will be a specialization of `operator T'.
2504 So, we find *all* the conversion operators, and then
2505 select from them. */
2508 methods = CLASSTYPE_METHOD_VEC (ctype);
2510 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2511 VEC_iterate (tree, methods, idx, ovl);
2514 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2515 /* There are no more conversion functions. */
2518 /* Glue all these conversion functions together
2519 with those we already have. */
2520 for (; ovl; ovl = OVL_NEXT (ovl))
2521 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2525 if (fns == NULL_TREE)
2527 error ("no member function %qD declared in %qT", name, ctype);
2528 return error_mark_node;
2531 TREE_OPERAND (declarator, 0) = fns;
2534 /* Figure out what exactly is being specialized at this point.
2535 Note that for an explicit instantiation, even one for a
2536 member function, we cannot tell apriori whether the
2537 instantiation is for a member template, or just a member
2538 function of a template class. Even if a member template is
2539 being instantiated, the member template arguments may be
2540 elided if they can be deduced from the rest of the
2542 tmpl = determine_specialization (declarator, decl,
2544 member_specialization,
2548 if (!tmpl || tmpl == error_mark_node)
2549 /* We couldn't figure out what this declaration was
2551 return error_mark_node;
2554 tree gen_tmpl = most_general_template (tmpl);
2556 if (explicit_instantiation)
2558 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2559 is done by do_decl_instantiation later. */
2561 int arg_depth = TMPL_ARGS_DEPTH (targs);
2562 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2564 if (arg_depth > parm_depth)
2566 /* If TMPL is not the most general template (for
2567 example, if TMPL is a friend template that is
2568 injected into namespace scope), then there will
2569 be too many levels of TARGS. Remove some of them
2574 new_targs = make_tree_vec (parm_depth);
2575 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2576 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2577 = TREE_VEC_ELT (targs, i);
2581 return instantiate_template (tmpl, targs, tf_error);
2584 /* If we thought that the DECL was a member function, but it
2585 turns out to be specializing a static member function,
2586 make DECL a static member function as well. */
2587 if (DECL_STATIC_FUNCTION_P (tmpl)
2588 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2589 revert_static_member_fn (decl);
2591 /* If this is a specialization of a member template of a
2592 template class, we want to return the TEMPLATE_DECL, not
2593 the specialization of it. */
2594 if (tsk == tsk_template)
2596 tree result = DECL_TEMPLATE_RESULT (tmpl);
2597 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2598 DECL_INITIAL (result) = NULL_TREE;
2602 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2603 DECL_SOURCE_LOCATION (result)
2604 = DECL_SOURCE_LOCATION (decl);
2605 /* We want to use the argument list specified in the
2606 definition, not in the original declaration. */
2607 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2608 for (parm = DECL_ARGUMENTS (result); parm;
2609 parm = DECL_CHAIN (parm))
2610 DECL_CONTEXT (parm) = result;
2612 return register_specialization (tmpl, gen_tmpl, targs,
2616 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2617 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2619 /* Inherit default function arguments from the template
2620 DECL is specializing. */
2621 copy_default_args_to_explicit_spec (decl);
2623 /* This specialization has the same protection as the
2624 template it specializes. */
2625 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2626 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2628 /* 7.1.1-1 [dcl.stc]
2630 A storage-class-specifier shall not be specified in an
2631 explicit specialization...
2633 The parser rejects these, so unless action is taken here,
2634 explicit function specializations will always appear with
2637 The action recommended by the C++ CWG in response to C++
2638 defect report 605 is to make the storage class and linkage
2639 of the explicit specialization match the templated function:
2641 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2643 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2645 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2646 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2648 /* This specialization has the same linkage and visibility as
2649 the function template it specializes. */
2650 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2651 if (! TREE_PUBLIC (decl))
2653 DECL_INTERFACE_KNOWN (decl) = 1;
2654 DECL_NOT_REALLY_EXTERN (decl) = 1;
2656 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2657 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2659 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2660 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2664 /* If DECL is a friend declaration, declared using an
2665 unqualified name, the namespace associated with DECL may
2666 have been set incorrectly. For example, in:
2668 template <typename T> void f(T);
2670 struct S { friend void f<int>(int); }
2673 we will have set the DECL_CONTEXT for the friend
2674 declaration to N, rather than to the global namespace. */
2675 if (DECL_NAMESPACE_SCOPE_P (decl))
2676 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2678 if (is_friend && !have_def)
2679 /* This is not really a declaration of a specialization.
2680 It's just the name of an instantiation. But, it's not
2681 a request for an instantiation, either. */
2682 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2683 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2684 /* This is indeed a specialization. In case of constructors
2685 and destructors, we need in-charge and not-in-charge
2686 versions in V3 ABI. */
2687 clone_function_decl (decl, /*update_method_vec_p=*/0);
2689 /* Register this specialization so that we can find it
2691 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2698 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2699 parameters. These are represented in the same format used for
2700 DECL_TEMPLATE_PARMS. */
2703 comp_template_parms (const_tree parms1, const_tree parms2)
2708 if (parms1 == parms2)
2711 for (p1 = parms1, p2 = parms2;
2712 p1 != NULL_TREE && p2 != NULL_TREE;
2713 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2715 tree t1 = TREE_VALUE (p1);
2716 tree t2 = TREE_VALUE (p2);
2719 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2720 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2722 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2725 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2727 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2728 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2730 /* If either of the template parameters are invalid, assume
2731 they match for the sake of error recovery. */
2732 if (parm1 == error_mark_node || parm2 == error_mark_node)
2735 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2738 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2739 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2740 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2742 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2747 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2748 /* One set of parameters has more parameters lists than the
2755 /* Determine whether PARM is a parameter pack. */
2758 template_parameter_pack_p (const_tree parm)
2760 /* Determine if we have a non-type template parameter pack. */
2761 if (TREE_CODE (parm) == PARM_DECL)
2762 return (DECL_TEMPLATE_PARM_P (parm)
2763 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2764 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2765 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2767 /* If this is a list of template parameters, we could get a
2768 TYPE_DECL or a TEMPLATE_DECL. */
2769 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2770 parm = TREE_TYPE (parm);
2772 /* Otherwise it must be a type template parameter. */
2773 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2774 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2775 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2778 /* Determine if T is a function parameter pack. */
2781 function_parameter_pack_p (const_tree t)
2783 if (t && TREE_CODE (t) == PARM_DECL)
2784 return FUNCTION_PARAMETER_PACK_P (t);
2788 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2789 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2792 get_function_template_decl (const_tree primary_func_tmpl_inst)
2794 if (! primary_func_tmpl_inst
2795 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2796 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2799 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2802 /* Return true iff the function parameter PARAM_DECL was expanded
2803 from the function parameter pack PACK. */
2806 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2808 if (DECL_ARTIFICIAL (param_decl)
2809 || !function_parameter_pack_p (pack))
2812 /* The parameter pack and its pack arguments have the same
2814 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2817 /* Determine whether ARGS describes a variadic template args list,
2818 i.e., one that is terminated by a template argument pack. */
2821 template_args_variadic_p (tree args)
2826 if (args == NULL_TREE)
2829 args = INNERMOST_TEMPLATE_ARGS (args);
2830 nargs = TREE_VEC_LENGTH (args);
2835 last_parm = TREE_VEC_ELT (args, nargs - 1);
2837 return ARGUMENT_PACK_P (last_parm);
2840 /* Generate a new name for the parameter pack name NAME (an
2841 IDENTIFIER_NODE) that incorporates its */
2844 make_ith_pack_parameter_name (tree name, int i)
2846 /* Munge the name to include the parameter index. */
2847 #define NUMBUF_LEN 128
2848 char numbuf[NUMBUF_LEN];
2852 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2853 newname_len = IDENTIFIER_LENGTH (name)
2854 + strlen (numbuf) + 2;
2855 newname = (char*)alloca (newname_len);
2856 snprintf (newname, newname_len,
2857 "%s#%i", IDENTIFIER_POINTER (name), i);
2858 return get_identifier (newname);
2861 /* Return true if T is a primary function, class or alias template
2865 primary_template_instantiation_p (const_tree t)
2870 if (TREE_CODE (t) == FUNCTION_DECL)
2871 return DECL_LANG_SPECIFIC (t)
2872 && DECL_TEMPLATE_INSTANTIATION (t)
2873 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2874 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2875 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2876 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2878 && TYPE_TEMPLATE_INFO (t)
2879 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
2880 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t)))
2885 /* Return true if PARM is a template template parameter. */
2888 template_template_parameter_p (const_tree parm)
2890 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2893 /* Return the template parameters of T if T is a
2894 primary template instantiation, NULL otherwise. */
2897 get_primary_template_innermost_parameters (const_tree t)
2899 tree parms = NULL, template_info = NULL;
2901 if ((template_info = get_template_info (t))
2902 && primary_template_instantiation_p (t))
2903 parms = INNERMOST_TEMPLATE_PARMS
2904 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2909 /* Return the template parameters of the LEVELth level from the full list
2910 of template parameters PARMS. */
2913 get_template_parms_at_level (tree parms, int level)
2917 || TREE_CODE (parms) != TREE_LIST
2918 || level > TMPL_PARMS_DEPTH (parms))
2921 for (p = parms; p; p = TREE_CHAIN (p))
2922 if (TMPL_PARMS_DEPTH (p) == level)
2928 /* Returns the template arguments of T if T is a template instantiation,
2932 get_template_innermost_arguments (const_tree t)
2934 tree args = NULL, template_info = NULL;
2936 if ((template_info = get_template_info (t))
2937 && TI_ARGS (template_info))
2938 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2943 /* Return the argument pack elements of T if T is a template argument pack,
2947 get_template_argument_pack_elems (const_tree t)
2949 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2950 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2953 return ARGUMENT_PACK_ARGS (t);
2956 /* Structure used to track the progress of find_parameter_packs_r. */
2957 struct find_parameter_pack_data
2959 /* TREE_LIST that will contain all of the parameter packs found by
2961 tree* parameter_packs;
2963 /* Set of AST nodes that have been visited by the traversal. */
2964 struct pointer_set_t *visited;
2967 /* Identifies all of the argument packs that occur in a template
2968 argument and appends them to the TREE_LIST inside DATA, which is a
2969 find_parameter_pack_data structure. This is a subroutine of
2970 make_pack_expansion and uses_parameter_packs. */
2972 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2975 struct find_parameter_pack_data* ppd =
2976 (struct find_parameter_pack_data*)data;
2977 bool parameter_pack_p = false;
2979 /* Handle type aliases/typedefs. */
2982 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
2983 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2985 if (TYPE_TEMPLATE_INFO (t))
2986 cp_walk_tree (&TYPE_TI_ARGS (t),
2987 &find_parameter_packs_r,
2993 /* Identify whether this is a parameter pack or not. */
2994 switch (TREE_CODE (t))
2996 case TEMPLATE_PARM_INDEX:
2997 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2998 parameter_pack_p = true;
3001 case TEMPLATE_TYPE_PARM:
3002 t = TYPE_MAIN_VARIANT (t);
3003 case TEMPLATE_TEMPLATE_PARM:
3004 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3005 parameter_pack_p = true;
3009 if (FUNCTION_PARAMETER_PACK_P (t))
3011 /* We don't want to walk into the type of a PARM_DECL,
3012 because we don't want to see the type parameter pack. */
3014 parameter_pack_p = true;
3019 parameter_pack_p = true;
3022 /* Not a parameter pack. */
3026 if (parameter_pack_p)
3028 /* Add this parameter pack to the list. */
3029 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3033 cp_walk_tree (&TYPE_CONTEXT (t),
3034 &find_parameter_packs_r, ppd, ppd->visited);
3036 /* This switch statement will return immediately if we don't find a
3038 switch (TREE_CODE (t))
3040 case TEMPLATE_PARM_INDEX:
3043 case BOUND_TEMPLATE_TEMPLATE_PARM:
3044 /* Check the template itself. */
3045 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3046 &find_parameter_packs_r, ppd, ppd->visited);
3047 /* Check the template arguments. */
3048 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3053 case TEMPLATE_TYPE_PARM:
3054 case TEMPLATE_TEMPLATE_PARM:
3061 if (TYPE_PTRMEMFUNC_P (t))
3067 if (TYPE_TEMPLATE_INFO (t))
3068 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3069 &find_parameter_packs_r, ppd, ppd->visited);
3076 cp_walk_tree (&TREE_TYPE (t),
3077 &find_parameter_packs_r, ppd, ppd->visited);
3081 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3086 case TYPE_PACK_EXPANSION:
3087 case EXPR_PACK_EXPANSION:
3092 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3097 case IDENTIFIER_NODE:
3098 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3110 /* Determines if the expression or type T uses any parameter packs. */
3112 uses_parameter_packs (tree t)
3114 tree parameter_packs = NULL_TREE;
3115 struct find_parameter_pack_data ppd;
3116 ppd.parameter_packs = ¶meter_packs;
3117 ppd.visited = pointer_set_create ();
3118 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3119 pointer_set_destroy (ppd.visited);
3120 return parameter_packs != NULL_TREE;
3123 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3124 representation a base-class initializer into a parameter pack
3125 expansion. If all goes well, the resulting node will be an
3126 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3129 make_pack_expansion (tree arg)
3132 tree parameter_packs = NULL_TREE;
3133 bool for_types = false;
3134 struct find_parameter_pack_data ppd;
3136 if (!arg || arg == error_mark_node)
3139 if (TREE_CODE (arg) == TREE_LIST)
3141 /* The only time we will see a TREE_LIST here is for a base
3142 class initializer. In this case, the TREE_PURPOSE will be a
3143 _TYPE node (representing the base class expansion we're
3144 initializing) and the TREE_VALUE will be a TREE_LIST
3145 containing the initialization arguments.
3147 The resulting expansion looks somewhat different from most
3148 expansions. Rather than returning just one _EXPANSION, we
3149 return a TREE_LIST whose TREE_PURPOSE is a
3150 TYPE_PACK_EXPANSION containing the bases that will be
3151 initialized. The TREE_VALUE will be identical to the
3152 original TREE_VALUE, which is a list of arguments that will
3153 be passed to each base. We do not introduce any new pack
3154 expansion nodes into the TREE_VALUE (although it is possible
3155 that some already exist), because the TREE_PURPOSE and
3156 TREE_VALUE all need to be expanded together with the same
3157 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3158 resulting TREE_PURPOSE will mention the parameter packs in
3159 both the bases and the arguments to the bases. */
3162 tree parameter_packs = NULL_TREE;
3164 /* Determine which parameter packs will be used by the base
3166 ppd.visited = pointer_set_create ();
3167 ppd.parameter_packs = ¶meter_packs;
3168 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3171 if (parameter_packs == NULL_TREE)
3173 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3174 pointer_set_destroy (ppd.visited);
3175 return error_mark_node;
3178 if (TREE_VALUE (arg) != void_type_node)
3180 /* Collect the sets of parameter packs used in each of the
3181 initialization arguments. */
3182 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3184 /* Determine which parameter packs will be expanded in this
3186 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3191 pointer_set_destroy (ppd.visited);
3193 /* Create the pack expansion type for the base type. */
3194 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3195 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3196 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3198 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3199 they will rarely be compared to anything. */
3200 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3202 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3205 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3208 /* Build the PACK_EXPANSION_* node. */
3210 ? cxx_make_type (TYPE_PACK_EXPANSION)
3211 : make_node (EXPR_PACK_EXPANSION);
3212 SET_PACK_EXPANSION_PATTERN (result, arg);
3213 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3215 /* Propagate type and const-expression information. */
3216 TREE_TYPE (result) = TREE_TYPE (arg);
3217 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3220 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3221 they will rarely be compared to anything. */
3222 SET_TYPE_STRUCTURAL_EQUALITY (result);
3224 /* Determine which parameter packs will be expanded. */
3225 ppd.parameter_packs = ¶meter_packs;
3226 ppd.visited = pointer_set_create ();
3227 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3228 pointer_set_destroy (ppd.visited);
3230 /* Make sure we found some parameter packs. */
3231 if (parameter_packs == NULL_TREE)
3234 error ("expansion pattern %<%T%> contains no argument packs", arg);
3236 error ("expansion pattern %<%E%> contains no argument packs", arg);
3237 return error_mark_node;
3239 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3244 /* Checks T for any "bare" parameter packs, which have not yet been
3245 expanded, and issues an error if any are found. This operation can
3246 only be done on full expressions or types (e.g., an expression
3247 statement, "if" condition, etc.), because we could have expressions like:
3249 foo(f(g(h(args)))...)
3251 where "args" is a parameter pack. check_for_bare_parameter_packs
3252 should not be called for the subexpressions args, h(args),
3253 g(h(args)), or f(g(h(args))), because we would produce erroneous
3256 Returns TRUE and emits an error if there were bare parameter packs,
3257 returns FALSE otherwise. */
3259 check_for_bare_parameter_packs (tree t)
3261 tree parameter_packs = NULL_TREE;
3262 struct find_parameter_pack_data ppd;
3264 if (!processing_template_decl || !t || t == error_mark_node)
3267 if (TREE_CODE (t) == TYPE_DECL)
3270 ppd.parameter_packs = ¶meter_packs;
3271 ppd.visited = pointer_set_create ();
3272 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3273 pointer_set_destroy (ppd.visited);
3275 if (parameter_packs)
3277 error ("parameter packs not expanded with %<...%>:");
3278 while (parameter_packs)
3280 tree pack = TREE_VALUE (parameter_packs);
3281 tree name = NULL_TREE;
3283 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3284 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3285 name = TYPE_NAME (pack);
3286 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3287 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3289 name = DECL_NAME (pack);
3292 inform (input_location, " %qD", name);
3294 inform (input_location, " <anonymous>");
3296 parameter_packs = TREE_CHAIN (parameter_packs);
3305 /* Expand any parameter packs that occur in the template arguments in
3308 expand_template_argument_pack (tree args)
3310 tree result_args = NULL_TREE;
3311 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3312 int num_result_args = -1;
3313 int non_default_args_count = -1;
3315 /* First, determine if we need to expand anything, and the number of
3316 slots we'll need. */
3317 for (in_arg = 0; in_arg < nargs; ++in_arg)
3319 tree arg = TREE_VEC_ELT (args, in_arg);
3320 if (arg == NULL_TREE)
3322 if (ARGUMENT_PACK_P (arg))
3324 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3325 if (num_result_args < 0)
3326 num_result_args = in_arg + num_packed;
3328 num_result_args += num_packed;
3332 if (num_result_args >= 0)
3337 /* If no expansion is necessary, we're done. */
3338 if (num_result_args < 0)
3341 /* Expand arguments. */
3342 result_args = make_tree_vec (num_result_args);
3343 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3344 non_default_args_count =
3345 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3346 for (in_arg = 0; in_arg < nargs; ++in_arg)
3348 tree arg = TREE_VEC_ELT (args, in_arg);
3349 if (ARGUMENT_PACK_P (arg))
3351 tree packed = ARGUMENT_PACK_ARGS (arg);
3352 int i, num_packed = TREE_VEC_LENGTH (packed);
3353 for (i = 0; i < num_packed; ++i, ++out_arg)
3354 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3355 if (non_default_args_count > 0)
3356 non_default_args_count += num_packed;
3360 TREE_VEC_ELT (result_args, out_arg) = arg;
3364 if (non_default_args_count >= 0)
3365 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3369 /* Checks if DECL shadows a template parameter.
3371 [temp.local]: A template-parameter shall not be redeclared within its
3372 scope (including nested scopes).
3374 Emits an error and returns TRUE if the DECL shadows a parameter,
3375 returns FALSE otherwise. */
3378 check_template_shadow (tree decl)
3382 /* If we're not in a template, we can't possibly shadow a template
3384 if (!current_template_parms)
3387 /* Figure out what we're shadowing. */
3388 if (TREE_CODE (decl) == OVERLOAD)
3389 decl = OVL_CURRENT (decl);
3390 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3392 /* If there's no previous binding for this name, we're not shadowing
3393 anything, let alone a template parameter. */
3397 /* If we're not shadowing a template parameter, we're done. Note
3398 that OLDDECL might be an OVERLOAD (or perhaps even an
3399 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3401 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3404 /* We check for decl != olddecl to avoid bogus errors for using a
3405 name inside a class. We check TPFI to avoid duplicate errors for
3406 inline member templates. */
3408 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3411 error ("declaration of %q+#D", decl);
3412 error (" shadows template parm %q+#D", olddecl);
3416 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3417 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3418 template parameters. */
3421 build_template_parm_index (int index,
3428 tree t = make_node (TEMPLATE_PARM_INDEX);
3429 TEMPLATE_PARM_IDX (t) = index;
3430 TEMPLATE_PARM_LEVEL (t) = level;
3431 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3432 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3433 TEMPLATE_PARM_DECL (t) = decl;
3434 TREE_TYPE (t) = type;
3435 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3436 TREE_READONLY (t) = TREE_READONLY (decl);
3441 /* Find the canonical type parameter for the given template type
3442 parameter. Returns the canonical type parameter, which may be TYPE
3443 if no such parameter existed. */
3446 canonical_type_parameter (tree type)
3449 int idx = TEMPLATE_TYPE_IDX (type);
3450 if (!canonical_template_parms)
3451 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3453 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3454 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3456 list = VEC_index (tree, canonical_template_parms, idx);
3457 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3458 list = TREE_CHAIN (list);
3461 return TREE_VALUE (list);
3464 VEC_replace(tree, canonical_template_parms, idx,
3465 tree_cons (NULL_TREE, type,
3466 VEC_index (tree, canonical_template_parms, idx)));
3471 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3472 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3473 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3474 new one is created. */
3477 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3478 tsubst_flags_t complain)
3480 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3481 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3482 != TEMPLATE_PARM_LEVEL (index) - levels)
3483 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3485 tree orig_decl = TEMPLATE_PARM_DECL (index);
3488 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3489 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3490 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3491 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3492 DECL_ARTIFICIAL (decl) = 1;
3493 SET_DECL_TEMPLATE_PARM_P (decl);
3495 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3496 TEMPLATE_PARM_LEVEL (index) - levels,
3497 TEMPLATE_PARM_ORIG_LEVEL (index),
3498 TEMPLATE_PARM_NUM_SIBLINGS (index),
3500 TEMPLATE_PARM_DESCENDANTS (index) = t;
3501 TEMPLATE_PARM_PARAMETER_PACK (t)
3502 = TEMPLATE_PARM_PARAMETER_PACK (index);
3504 /* Template template parameters need this. */
3505 if (TREE_CODE (decl) == TEMPLATE_DECL)
3506 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3507 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3511 return TEMPLATE_PARM_DESCENDANTS (index);
3514 /* Process information from new template parameter PARM and append it
3515 to the LIST being built. This new parameter is a non-type
3516 parameter iff IS_NON_TYPE is true. This new parameter is a
3517 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3518 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3519 parameter list PARM belongs to. This is used used to create a
3520 proper canonical type for the type of PARM that is to be created,
3521 iff PARM is a type. If the size is not known, this parameter shall
3525 process_template_parm (tree list, location_t parm_loc, tree parm,
3526 bool is_non_type, bool is_parameter_pack,
3527 unsigned num_template_parms)
3534 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3535 defval = TREE_PURPOSE (parm);
3539 tree p = tree_last (list);
3541 if (p && TREE_VALUE (p) != error_mark_node)
3544 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3545 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3547 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3557 parm = TREE_VALUE (parm);
3559 SET_DECL_TEMPLATE_PARM_P (parm);
3561 if (TREE_TYPE (parm) == error_mark_node)
3563 err_parm_list = build_tree_list (defval, parm);
3564 TREE_VALUE (err_parm_list) = error_mark_node;
3565 return chainon (list, err_parm_list);
3571 The top-level cv-qualifiers on the template-parameter are
3572 ignored when determining its type. */
3573 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3574 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3576 err_parm_list = build_tree_list (defval, parm);
3577 TREE_VALUE (err_parm_list) = error_mark_node;
3578 return chainon (list, err_parm_list);
3581 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3583 /* This template parameter is not a parameter pack, but it
3584 should be. Complain about "bare" parameter packs. */
3585 check_for_bare_parameter_packs (TREE_TYPE (parm));
3587 /* Recover by calling this a parameter pack. */
3588 is_parameter_pack = true;
3592 /* A template parameter is not modifiable. */
3593 TREE_CONSTANT (parm) = 1;
3594 TREE_READONLY (parm) = 1;
3595 decl = build_decl (parm_loc,
3596 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3597 TREE_CONSTANT (decl) = 1;
3598 TREE_READONLY (decl) = 1;
3599 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3600 = build_template_parm_index (idx, processing_template_decl,
3601 processing_template_decl,
3603 decl, TREE_TYPE (parm));
3605 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3606 = is_parameter_pack;
3611 parm = TREE_VALUE (TREE_VALUE (parm));
3613 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3615 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3616 /* This is for distinguishing between real templates and template
3617 template parameters */
3618 TREE_TYPE (parm) = t;
3619 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3624 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3625 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3626 decl = build_decl (parm_loc,
3627 TYPE_DECL, parm, t);
3630 TYPE_NAME (t) = decl;
3631 TYPE_STUB_DECL (t) = decl;
3633 TEMPLATE_TYPE_PARM_INDEX (t)
3634 = build_template_parm_index (idx, processing_template_decl,
3635 processing_template_decl,
3637 decl, TREE_TYPE (parm));
3638 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3639 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3641 DECL_ARTIFICIAL (decl) = 1;
3642 SET_DECL_TEMPLATE_PARM_P (decl);
3644 parm = build_tree_list (defval, parm);
3645 return chainon (list, parm);
3648 /* The end of a template parameter list has been reached. Process the
3649 tree list into a parameter vector, converting each parameter into a more
3650 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3654 end_template_parm_list (tree parms)
3658 tree saved_parmlist = make_tree_vec (list_length (parms));
3660 current_template_parms
3661 = tree_cons (size_int (processing_template_decl),
3662 saved_parmlist, current_template_parms);
3664 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3666 next = TREE_CHAIN (parm);
3667 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3668 TREE_CHAIN (parm) = NULL_TREE;
3671 --processing_template_parmlist;
3673 return saved_parmlist;
3676 /* Create a new type almost identical to TYPE but which has the
3677 following differences:
3679 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3680 template sibling parameters of T.
3682 2/ T has a new canonical type that matches the new number
3685 3/ From now on, T is going to be what lookups referring to the
3686 name of TYPE will return. No lookup should return TYPE anymore.
3688 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3690 This is a subroutine of fixup_template_parms. */
3693 fixup_template_type_parm_type (tree type, int num_parms)
3695 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3697 /* This is the decl which name is inserted into the symbol table for
3698 the template parm type. So whenever we lookup the type name, this
3699 is the DECL we get. */
3702 /* Do not fix up the type twice. */
3703 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3706 t = copy_type (type);
3707 decl = TYPE_NAME (t);
3709 TYPE_MAIN_VARIANT (t) = t;
3710 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3711 TYPE_POINTER_TO (t) = 0;
3712 TYPE_REFERENCE_TO (t) = 0;
3714 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3715 TEMPLATE_PARM_LEVEL (orig_idx),
3716 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3719 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3720 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3721 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3723 TYPE_STUB_DECL (t) = decl;
3724 TEMPLATE_TYPE_DECL (t) = decl;
3725 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3726 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3728 /* Update the type associated to the type name stored in the symbol
3729 table. Now, whenever the type name is looked up, the resulting
3730 type is properly fixed up. */
3731 TREE_TYPE (decl) = t;
3733 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3738 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3739 identical to I, but that is fixed up as to:
3741 1/ carry the number of sibling parms (NUM_PARMS) of the template
3742 parm represented by I.
3744 2/ replace all references to template parm types declared before I
3745 (in the same template parm list as I) by references to template
3746 parm types contained in ARGS. ARGS should contain the list of
3747 template parms that have been fixed up so far, in a form suitable
3748 to be passed to tsubst.
3750 This is a subroutine of fixup_template_parms. */
3753 fixup_template_parm_index (tree i, tree args, int num_parms)
3755 tree index, decl, type;
3758 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3759 /* Do not fix up the index twice. */
3760 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3763 decl = TEMPLATE_PARM_DECL (i);
3764 type = TREE_TYPE (decl);
3766 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3767 TEMPLATE_PARM_LEVEL (i),
3768 TEMPLATE_PARM_ORIG_LEVEL (i),
3772 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3773 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3775 type = tsubst (type, args, tf_none, NULL_TREE);
3777 TREE_TYPE (decl) = type;
3778 TREE_TYPE (index) = type;
3784 This is a subroutine of fixup_template_parms.
3786 It computes the canonical type of the type of the template
3787 parameter PARM_DESC and update all references to that type so that
3788 they use the newly computed canonical type. No access check is
3789 performed during the fixup. PARM_DESC is a TREE_LIST which
3790 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3791 default argument of the template parm if any. IDX is the index of
3792 the template parameter, starting at 0. NUM_PARMS is the number of
3793 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3794 TREE_VEC containing the full set of template parameters in a form
3795 suitable to be passed to substs functions as their ARGS
3796 argument. This is what current_template_args returns for a given
3797 template. The innermost vector of args in ARGLIST is the set of
3798 template parms that have been fixed up so far. This function adds
3799 the fixed up parameter into that vector. */
3802 fixup_template_parm (tree parm_desc,
3807 tree parm = TREE_VALUE (parm_desc);
3808 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3810 push_deferring_access_checks (dk_no_check);
3812 if (TREE_CODE (parm) == TYPE_DECL)
3814 /* PARM is a template type parameter. Fix up its type, add
3815 the fixed-up template parm to the vector of fixed-up
3816 template parms so far, and substitute the fixed-up
3817 template parms into the default argument of this
3820 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3821 TREE_TYPE (parm) = t;
3823 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3825 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3827 /* PARM is a template template parameter. This is going to
3829 tree tparms, targs, innermost_args, t;
3832 /* First, fix up the parms of the template template parm
3833 because the parms are involved in defining the new canonical
3834 type of the template template parm. */
3836 /* So we need to substitute the template parm types that have
3837 been fixed up so far into the template parms of this template
3838 template parm. E.g, consider this:
3840 template<class T, template<T u> class TT> class S;
3842 In this case we want to substitute T into the
3843 template parameters of TT.
3845 So let's walk the template parms of PARM here, and
3846 tsubst ARGLIST into into each of the template
3849 /* For this substitution we need to build the full set of
3850 template parameters and use that as arguments for the
3851 tsubsting function. */
3852 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3854 /* This will contain the innermost parms of PARM into which
3855 we have substituted so far. */
3856 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3857 targs = add_to_template_args (arglist, innermost_args);
3858 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3862 parameter = TREE_VEC_ELT (tparms, j);
3864 /* INNERMOST_ARGS needs to have at least the same number
3865 of elements as the index PARAMETER, ortherwise
3866 tsubsting into PARAMETER will result in partially
3867 instantiating it, reducing its tempate parm
3868 level. Let's tactically fill INNERMOST_ARGS for that
3870 TREE_VEC_ELT (innermost_args, j) =
3871 template_parm_to_arg (parameter);
3873 fixup_template_parm (parameter, j,
3874 TREE_VEC_LENGTH (tparms),
3878 /* Now fix up the type of the template template parm. */
3880 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3881 TREE_TYPE (parm) = t;
3883 TREE_VEC_ELT (fixedup_args, idx) =
3884 template_parm_to_arg (parm_desc);
3886 else if (TREE_CODE (parm) == PARM_DECL)
3888 /* PARM is a non-type template parameter. We need to:
3890 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3891 proper number of sibling parameters.
3893 * Make lookups of the template parameter return a reference
3894 to the fixed-up index. No lookup should return references
3895 to the former index anymore.
3897 * Substitute the template parms that got fixed up so far
3899 * into the type of PARM. */
3901 tree index = DECL_INITIAL (parm);
3903 /* PUSHED_DECL is the decl added to the symbol table with
3904 the name of the parameter. E,g:
3906 template<class T, T u> //#0
3907 auto my_function(T t) -> decltype(u); //#1
3909 Here, when looking up u at //#1, we get the decl of u
3910 resulting from the declaration in #0. This is what
3911 PUSHED_DECL is. We need to replace the reference to the
3912 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3913 fixed-up TEMPLATE_PARM_INDEX. */
3914 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3916 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3917 fixup the type of PUSHED_DECL as well and luckily
3918 fixup_template_parm_index does it for us too. */
3919 tree fixed_up_index =
3920 fixup_template_parm_index (index, arglist, num_parms);
3922 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3924 /* Add this fixed up PARM to the template parms we've fixed
3925 up so far and use that to substitute the fixed-up
3926 template parms into the type of PARM. */
3927 TREE_VEC_ELT (fixedup_args, idx) =
3928 template_parm_to_arg (parm_desc);
3929 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3930 tf_none, NULL_TREE);
3933 TREE_PURPOSE (parm_desc) =
3934 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3935 arglist, tf_none, parm);
3937 pop_deferring_access_checks ();
3940 /* Walk the current template parms and properly compute the canonical
3941 types of the dependent types created during
3942 cp_parser_template_parameter_list. */
3945 fixup_template_parms (void)
3952 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3953 if (parameter_vec == NULL_TREE)
3956 num_parms = TREE_VEC_LENGTH (parameter_vec);
3958 /* This vector contains the current innermost template parms that
3959 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3960 to be passed to tsubst* functions as their ARGS argument. */
3961 fixedup_args = make_tree_vec (num_parms);
3963 /* This vector contains the full set of template parms in a form
3964 suitable to be passed to substs functions as their ARGS
3966 arglist = current_template_args ();
3967 arglist = add_outermost_template_args (arglist, fixedup_args);
3969 /* Let's do the proper fixup now. */
3970 for (i = 0; i < num_parms; ++i)
3971 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3972 i, num_parms, arglist);
3975 /* end_template_decl is called after a template declaration is seen. */
3978 end_template_decl (void)
3980 reset_specialization ();
3982 if (! processing_template_decl)
3985 /* This matches the pushlevel in begin_template_parm_list. */
3988 --processing_template_decl;
3989 current_template_parms = TREE_CHAIN (current_template_parms);
3992 /* Takes a TREE_LIST representing a template parameter and convert it
3993 into an argument suitable to be passed to the type substitution
3994 functions. Note that If the TREE_LIST contains an error_mark
3995 node, the returned argument is error_mark_node. */
3998 template_parm_to_arg (tree t)
4002 || TREE_CODE (t) != TREE_LIST)
4005 if (error_operand_p (TREE_VALUE (t)))
4006 return error_mark_node;
4010 if (TREE_CODE (t) == TYPE_DECL
4011 || TREE_CODE (t) == TEMPLATE_DECL)
4015 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4017 /* Turn this argument into a TYPE_ARGUMENT_PACK
4018 with a single element, which expands T. */
4019 tree vec = make_tree_vec (1);
4020 #ifdef ENABLE_CHECKING
4021 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4022 (vec, TREE_VEC_LENGTH (vec));
4024 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4026 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4027 SET_ARGUMENT_PACK_ARGS (t, vec);
4032 t = DECL_INITIAL (t);
4034 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4036 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4037 with a single element, which expands T. */
4038 tree vec = make_tree_vec (1);
4039 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4040 #ifdef ENABLE_CHECKING
4041 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4042 (vec, TREE_VEC_LENGTH (vec));
4044 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4046 t = make_node (NONTYPE_ARGUMENT_PACK);
4047 SET_ARGUMENT_PACK_ARGS (t, vec);
4048 TREE_TYPE (t) = type;
4054 /* This function returns TRUE if PARM_PACK is a template parameter
4055 pack and if ARG_PACK is what template_parm_to_arg returned when
4056 passed PARM_PACK. */
4059 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4061 /* For clarity in the comments below let's use the representation
4062 argument_pack<elements>' to denote an argument pack and its
4065 In the 'if' block below, we want to detect cases where
4066 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4067 check if ARG_PACK is an argument pack which sole element is
4068 the expansion of PARM_PACK. That argument pack is typically
4069 created by template_parm_to_arg when passed a parameter
4073 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4074 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4076 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4077 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4078 /* So we have an argument_pack<P...>. We want to test if P
4079 is actually PARM_PACK. We will not use cp_tree_equal to
4080 test P and PARM_PACK because during type fixup (by
4081 fixup_template_parm) P can be a pre-fixup version of a
4082 type and PARM_PACK be its post-fixup version.
4083 cp_tree_equal would consider them as different even
4084 though we would want to consider them compatible for our
4085 precise purpose here.
4087 Thus we are going to consider that P and PARM_PACK are
4088 compatible if they have the same DECL. */
4089 if ((/* If ARG_PACK is a type parameter pack named by the
4090 same DECL as parm_pack ... */
4092 && TYPE_P (parm_pack)
4093 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4094 /* ... or if PARM_PACK is a non-type parameter named by the
4095 same DECL as ARG_PACK. Note that PARM_PACK being a
4096 non-type parameter means it's either a PARM_DECL or a
4097 TEMPLATE_PARM_INDEX. */
4098 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4099 && ((TREE_CODE (parm_pack) == PARM_DECL
4100 && (TEMPLATE_PARM_DECL (pattern)
4101 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4102 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4103 && (TEMPLATE_PARM_DECL (pattern)
4104 == TEMPLATE_PARM_DECL (parm_pack))))))
4105 && template_parameter_pack_p (pattern))
4111 /* Within the declaration of a template, return all levels of template
4112 parameters that apply. The template parameters are represented as
4113 a TREE_VEC, in the form documented in cp-tree.h for template
4117 current_template_args (void)
4120 tree args = NULL_TREE;
4121 int length = TMPL_PARMS_DEPTH (current_template_parms);
4124 /* If there is only one level of template parameters, we do not
4125 create a TREE_VEC of TREE_VECs. Instead, we return a single
4126 TREE_VEC containing the arguments. */
4128 args = make_tree_vec (length);
4130 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4132 tree a = copy_node (TREE_VALUE (header));
4135 TREE_TYPE (a) = NULL_TREE;
4136 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4137 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4139 #ifdef ENABLE_CHECKING
4140 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4144 TREE_VEC_ELT (args, --l) = a;
4149 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4150 /* This can happen for template parms of a template template
4153 template<template<class T, class U> class TT> struct S;
4155 Consider the level of the parms of TT; T and U both have
4156 level 2; TT has no template parm of level 1. So in this case
4157 the first element of full_template_args is NULL_TREE. If we
4158 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4159 of 2. This will make tsubst wrongly consider that T and U
4160 have level 1. Instead, let's create a dummy vector as the
4161 first element of full_template_args so that TMPL_ARG_DEPTH
4162 returns the correct depth for args. */
4163 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4167 /* Update the declared TYPE by doing any lookups which were thought to be
4168 dependent, but are not now that we know the SCOPE of the declarator. */
4171 maybe_update_decl_type (tree orig_type, tree scope)
4173 tree type = orig_type;
4175 if (type == NULL_TREE)
4178 if (TREE_CODE (orig_type) == TYPE_DECL)
4179 type = TREE_TYPE (type);
4181 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4182 && dependent_type_p (type)
4183 /* Don't bother building up the args in this case. */
4184 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4186 /* tsubst in the args corresponding to the template parameters,
4187 including auto if present. Most things will be unchanged, but
4188 make_typename_type and tsubst_qualified_id will resolve
4189 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4190 tree args = current_template_args ();
4191 tree auto_node = type_uses_auto (type);
4195 tree auto_vec = make_tree_vec (1);
4196 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4197 args = add_to_template_args (args, auto_vec);
4199 pushed = push_scope (scope);
4200 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4205 if (type == error_mark_node)
4208 if (TREE_CODE (orig_type) == TYPE_DECL)
4210 if (same_type_p (type, TREE_TYPE (orig_type)))
4213 type = TYPE_NAME (type);
4218 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4219 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4220 a member template. Used by push_template_decl below. */
4223 build_template_decl (tree decl, tree parms, bool member_template_p)
4225 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4226 DECL_TEMPLATE_PARMS (tmpl) = parms;
4227 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4228 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4229 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4234 struct template_parm_data
4236 /* The level of the template parameters we are currently
4240 /* The index of the specialization argument we are currently
4244 /* An array whose size is the number of template parameters. The
4245 elements are nonzero if the parameter has been used in any one
4246 of the arguments processed so far. */
4249 /* An array whose size is the number of template arguments. The
4250 elements are nonzero if the argument makes use of template
4251 parameters of this level. */
4252 int* arg_uses_template_parms;
4255 /* Subroutine of push_template_decl used to see if each template
4256 parameter in a partial specialization is used in the explicit
4257 argument list. If T is of the LEVEL given in DATA (which is
4258 treated as a template_parm_data*), then DATA->PARMS is marked
4262 mark_template_parm (tree t, void* data)
4266 struct template_parm_data* tpd = (struct template_parm_data*) data;
4268 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4270 level = TEMPLATE_PARM_LEVEL (t);
4271 idx = TEMPLATE_PARM_IDX (t);
4275 level = TEMPLATE_TYPE_LEVEL (t);
4276 idx = TEMPLATE_TYPE_IDX (t);
4279 if (level == tpd->level)
4281 tpd->parms[idx] = 1;
4282 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4285 /* Return zero so that for_each_template_parm will continue the
4286 traversal of the tree; we want to mark *every* template parm. */
4290 /* Process the partial specialization DECL. */
4293 process_partial_specialization (tree decl)
4295 tree type = TREE_TYPE (decl);
4296 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4297 tree specargs = CLASSTYPE_TI_ARGS (type);
4298 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4299 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4302 int nargs = TREE_VEC_LENGTH (inner_args);
4305 bool did_error_intro = false;
4306 struct template_parm_data tpd;
4307 struct template_parm_data tpd2;
4309 gcc_assert (current_template_parms);
4311 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4312 ntparms = TREE_VEC_LENGTH (inner_parms);
4314 /* We check that each of the template parameters given in the
4315 partial specialization is used in the argument list to the
4316 specialization. For example:
4318 template <class T> struct S;
4319 template <class T> struct S<T*>;
4321 The second declaration is OK because `T*' uses the template
4322 parameter T, whereas
4324 template <class T> struct S<int>;
4326 is no good. Even trickier is:
4337 The S2<T> declaration is actually invalid; it is a
4338 full-specialization. Of course,
4341 struct S2<T (*)(U)>;
4343 or some such would have been OK. */
4344 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4345 tpd.parms = XALLOCAVEC (int, ntparms);
4346 memset (tpd.parms, 0, sizeof (int) * ntparms);
4348 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4349 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4350 for (i = 0; i < nargs; ++i)
4352 tpd.current_arg = i;
4353 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4354 &mark_template_parm,
4357 /*include_nondeduced_p=*/false);
4359 for (i = 0; i < ntparms; ++i)
4360 if (tpd.parms[i] == 0)
4362 /* One of the template parms was not used in the
4364 if (!did_error_intro)
4366 error ("template parameters not used in partial specialization:");
4367 did_error_intro = true;
4370 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4373 if (did_error_intro)
4374 return error_mark_node;
4376 /* [temp.class.spec]
4378 The argument list of the specialization shall not be identical to
4379 the implicit argument list of the primary template. */
4380 if (comp_template_args
4382 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4384 error ("partial specialization %qT does not specialize any template arguments", type);
4386 /* [temp.class.spec]
4388 A partially specialized non-type argument expression shall not
4389 involve template parameters of the partial specialization except
4390 when the argument expression is a simple identifier.
4392 The type of a template parameter corresponding to a specialized
4393 non-type argument shall not be dependent on a parameter of the
4396 Also, we verify that pack expansions only occur at the
4397 end of the argument list. */
4398 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4400 for (i = 0; i < nargs; ++i)
4402 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4403 tree arg = TREE_VEC_ELT (inner_args, i);
4404 tree packed_args = NULL_TREE;
4407 if (ARGUMENT_PACK_P (arg))
4409 /* Extract the arguments from the argument pack. We'll be
4410 iterating over these in the following loop. */
4411 packed_args = ARGUMENT_PACK_ARGS (arg);
4412 len = TREE_VEC_LENGTH (packed_args);
4415 for (j = 0; j < len; j++)
4418 /* Get the Jth argument in the parameter pack. */
4419 arg = TREE_VEC_ELT (packed_args, j);
4421 if (PACK_EXPANSION_P (arg))
4423 /* Pack expansions must come at the end of the
4425 if ((packed_args && j < len - 1)
4426 || (!packed_args && i < nargs - 1))
4428 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4429 error ("parameter pack argument %qE must be at the "
4430 "end of the template argument list", arg);
4432 error ("parameter pack argument %qT must be at the "
4433 "end of the template argument list", arg);
4437 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4438 /* We only care about the pattern. */
4439 arg = PACK_EXPANSION_PATTERN (arg);
4441 if (/* These first two lines are the `non-type' bit. */
4443 && TREE_CODE (arg) != TEMPLATE_DECL
4444 /* This next line is the `argument expression is not just a
4445 simple identifier' condition and also the `specialized
4446 non-type argument' bit. */
4447 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4449 if ((!packed_args && tpd.arg_uses_template_parms[i])
4450 || (packed_args && uses_template_parms (arg)))
4451 error ("template argument %qE involves template parameter(s)",
4455 /* Look at the corresponding template parameter,
4456 marking which template parameters its type depends
4458 tree type = TREE_TYPE (parm);
4462 /* We haven't yet initialized TPD2. Do so now. */
4463 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4464 /* The number of parameters here is the number in the
4465 main template, which, as checked in the assertion
4467 tpd2.parms = XALLOCAVEC (int, nargs);
4469 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4472 /* Mark the template parameters. But this time, we're
4473 looking for the template parameters of the main
4474 template, not in the specialization. */
4475 tpd2.current_arg = i;
4476 tpd2.arg_uses_template_parms[i] = 0;
4477 memset (tpd2.parms, 0, sizeof (int) * nargs);
4478 for_each_template_parm (type,
4479 &mark_template_parm,
4482 /*include_nondeduced_p=*/false);
4484 if (tpd2.arg_uses_template_parms [i])
4486 /* The type depended on some template parameters.
4487 If they are fully specialized in the
4488 specialization, that's OK. */
4491 for (j = 0; j < nargs; ++j)
4492 if (tpd2.parms[j] != 0
4493 && tpd.arg_uses_template_parms [j])
4496 error_n (input_location, count,
4497 "type %qT of template argument %qE depends "
4498 "on a template parameter",
4499 "type %qT of template argument %qE depends "
4500 "on template parameters",
4509 /* We should only get here once. */
4510 gcc_assert (!COMPLETE_TYPE_P (type));
4512 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4513 = tree_cons (specargs, inner_parms,
4514 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4515 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4517 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4518 inst = TREE_CHAIN (inst))
4520 tree inst_type = TREE_VALUE (inst);
4521 if (COMPLETE_TYPE_P (inst_type)
4522 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4524 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4525 if (spec && TREE_TYPE (spec) == type)
4526 permerror (input_location,
4527 "partial specialization of %qT after instantiation "
4528 "of %qT", type, inst_type);
4535 /* Check that a template declaration's use of default arguments and
4536 parameter packs is not invalid. Here, PARMS are the template
4537 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4538 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4542 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4543 declaration (but not a definition); 1 indicates a declaration, 2
4544 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4545 emitted for extraneous default arguments.
4547 Returns TRUE if there were no errors found, FALSE otherwise. */
4550 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4551 int is_partial, int is_friend_decl)
4554 int last_level_to_check;
4556 bool no_errors = true;
4560 A default template-argument shall not be specified in a
4561 function template declaration or a function template definition, nor
4562 in the template-parameter-list of the definition of a member of a
4565 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4566 /* You can't have a function template declaration in a local
4567 scope, nor you can you define a member of a class template in a
4571 if (current_class_type
4572 && !TYPE_BEING_DEFINED (current_class_type)
4573 && DECL_LANG_SPECIFIC (decl)
4574 && DECL_DECLARES_FUNCTION_P (decl)
4575 /* If this is either a friend defined in the scope of the class
4576 or a member function. */
4577 && (DECL_FUNCTION_MEMBER_P (decl)
4578 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4579 : DECL_FRIEND_CONTEXT (decl)
4580 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4582 /* And, if it was a member function, it really was defined in
4583 the scope of the class. */
4584 && (!DECL_FUNCTION_MEMBER_P (decl)
4585 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4586 /* We already checked these parameters when the template was
4587 declared, so there's no need to do it again now. This function
4588 was defined in class scope, but we're processing it's body now
4589 that the class is complete. */
4592 /* Core issue 226 (C++0x only): the following only applies to class
4594 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4598 If a template-parameter has a default template-argument, all
4599 subsequent template-parameters shall have a default
4600 template-argument supplied. */
4601 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4603 tree inner_parms = TREE_VALUE (parm_level);
4604 int ntparms = TREE_VEC_LENGTH (inner_parms);
4605 int seen_def_arg_p = 0;
4608 for (i = 0; i < ntparms; ++i)
4610 tree parm = TREE_VEC_ELT (inner_parms, i);
4612 if (parm == error_mark_node)
4615 if (TREE_PURPOSE (parm))
4617 else if (seen_def_arg_p
4618 && !template_parameter_pack_p (TREE_VALUE (parm)))
4620 error ("no default argument for %qD", TREE_VALUE (parm));
4621 /* For better subsequent error-recovery, we indicate that
4622 there should have been a default argument. */
4623 TREE_PURPOSE (parm) = error_mark_node;
4629 /* Don't complain about an enclosing partial
4631 && parm_level == parms
4632 && TREE_CODE (decl) == TYPE_DECL
4634 && template_parameter_pack_p (TREE_VALUE (parm)))
4636 /* A primary class template can only have one
4637 parameter pack, at the end of the template
4640 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4641 error ("parameter pack %qE must be at the end of the"
4642 " template parameter list", TREE_VALUE (parm));
4644 error ("parameter pack %qT must be at the end of the"
4645 " template parameter list",
4646 TREE_TYPE (TREE_VALUE (parm)));
4648 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4656 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4660 /* For an ordinary class template, default template arguments are
4661 allowed at the innermost level, e.g.:
4662 template <class T = int>
4664 but, in a partial specialization, they're not allowed even
4665 there, as we have in [temp.class.spec]:
4667 The template parameter list of a specialization shall not
4668 contain default template argument values.
4670 So, for a partial specialization, or for a function template
4671 (in C++98/C++03), we look at all of them. */
4674 /* But, for a primary class template that is not a partial
4675 specialization we look at all template parameters except the
4677 parms = TREE_CHAIN (parms);
4679 /* Figure out what error message to issue. */
4680 if (is_friend_decl == 2)
4681 msg = G_("default template arguments may not be used in function template "
4682 "friend re-declaration");
4683 else if (is_friend_decl)
4684 msg = G_("default template arguments may not be used in function template "
4685 "friend declarations");
4686 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4687 msg = G_("default template arguments may not be used in function templates "
4688 "without -std=c++11 or -std=gnu++11");
4689 else if (is_partial)
4690 msg = G_("default template arguments may not be used in "
4691 "partial specializations");
4693 msg = G_("default argument for template parameter for class enclosing %qD");
4695 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4696 /* If we're inside a class definition, there's no need to
4697 examine the parameters to the class itself. On the one
4698 hand, they will be checked when the class is defined, and,
4699 on the other, default arguments are valid in things like:
4700 template <class T = double>
4701 struct S { template <class U> void f(U); };
4702 Here the default argument for `S' has no bearing on the
4703 declaration of `f'. */
4704 last_level_to_check = template_class_depth (current_class_type) + 1;
4706 /* Check everything. */
4707 last_level_to_check = 0;
4709 for (parm_level = parms;
4710 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4711 parm_level = TREE_CHAIN (parm_level))
4713 tree inner_parms = TREE_VALUE (parm_level);
4717 ntparms = TREE_VEC_LENGTH (inner_parms);
4718 for (i = 0; i < ntparms; ++i)
4720 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4723 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4728 if (is_friend_decl == 2)
4735 /* Clear out the default argument so that we are not
4737 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4741 /* At this point, if we're still interested in issuing messages,
4742 they must apply to classes surrounding the object declared. */
4744 msg = G_("default argument for template parameter for class "
4751 /* Worker for push_template_decl_real, called via
4752 for_each_template_parm. DATA is really an int, indicating the
4753 level of the parameters we are interested in. If T is a template
4754 parameter of that level, return nonzero. */
4757 template_parm_this_level_p (tree t, void* data)
4759 int this_level = *(int *)data;
4762 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4763 level = TEMPLATE_PARM_LEVEL (t);
4765 level = TEMPLATE_TYPE_LEVEL (t);
4766 return level == this_level;
4769 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4770 parameters given by current_template_args, or reuses a
4771 previously existing one, if appropriate. Returns the DECL, or an
4772 equivalent one, if it is replaced via a call to duplicate_decls.
4774 If IS_FRIEND is true, DECL is a friend declaration. */
4777 push_template_decl_real (tree decl, bool is_friend)
4785 int new_template_p = 0;
4786 /* True if the template is a member template, in the sense of
4788 bool member_template_p = false;
4790 if (decl == error_mark_node || !current_template_parms)
4791 return error_mark_node;
4793 /* See if this is a partial specialization. */
4794 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4795 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4796 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4798 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4802 /* For a friend, we want the context of the friend function, not
4803 the type of which it is a friend. */
4804 ctx = CP_DECL_CONTEXT (decl);
4805 else if (CP_DECL_CONTEXT (decl)
4806 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4807 /* In the case of a virtual function, we want the class in which
4809 ctx = CP_DECL_CONTEXT (decl);
4811 /* Otherwise, if we're currently defining some class, the DECL
4812 is assumed to be a member of the class. */
4813 ctx = current_scope ();
4815 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4818 if (!DECL_CONTEXT (decl))
4819 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4821 /* See if this is a primary template. */
4822 if (is_friend && ctx)
4823 /* A friend template that specifies a class context, i.e.
4824 template <typename T> friend void A<T>::f();
4828 primary = template_parm_scope_p ();
4832 if (DECL_CLASS_SCOPE_P (decl))
4833 member_template_p = true;
4834 if (TREE_CODE (decl) == TYPE_DECL
4835 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4837 error ("template class without a name");
4838 return error_mark_node;
4840 else if (TREE_CODE (decl) == FUNCTION_DECL)
4842 if (DECL_DESTRUCTOR_P (decl))
4846 A destructor shall not be a member template. */
4847 error ("destructor %qD declared as member template", decl);
4848 return error_mark_node;
4850 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4851 && (!prototype_p (TREE_TYPE (decl))
4852 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4853 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4854 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4855 == void_list_node)))
4857 /* [basic.stc.dynamic.allocation]
4859 An allocation function can be a function
4860 template. ... Template allocation functions shall
4861 have two or more parameters. */
4862 error ("invalid template declaration of %qD", decl);
4863 return error_mark_node;
4866 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4867 && CLASS_TYPE_P (TREE_TYPE (decl)))
4869 else if (TREE_CODE (decl) == TYPE_DECL
4870 && TYPE_DECL_ALIAS_P (decl))
4871 /* alias-declaration */
4872 gcc_assert (!DECL_ARTIFICIAL (decl));
4875 error ("template declaration of %q#D", decl);
4876 return error_mark_node;
4880 /* Check to see that the rules regarding the use of default
4881 arguments are not being violated. */
4882 check_default_tmpl_args (decl, current_template_parms,
4883 primary, is_partial, /*is_friend_decl=*/0);
4885 /* Ensure that there are no parameter packs in the type of this
4886 declaration that have not been expanded. */
4887 if (TREE_CODE (decl) == FUNCTION_DECL)
4889 /* Check each of the arguments individually to see if there are
4890 any bare parameter packs. */
4891 tree type = TREE_TYPE (decl);
4892 tree arg = DECL_ARGUMENTS (decl);
4893 tree argtype = TYPE_ARG_TYPES (type);
4895 while (arg && argtype)
4897 if (!FUNCTION_PARAMETER_PACK_P (arg)
4898 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4900 /* This is a PARM_DECL that contains unexpanded parameter
4901 packs. We have already complained about this in the
4902 check_for_bare_parameter_packs call, so just replace
4903 these types with ERROR_MARK_NODE. */
4904 TREE_TYPE (arg) = error_mark_node;
4905 TREE_VALUE (argtype) = error_mark_node;
4908 arg = DECL_CHAIN (arg);
4909 argtype = TREE_CHAIN (argtype);
4912 /* Check for bare parameter packs in the return type and the
4913 exception specifiers. */
4914 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4915 /* Errors were already issued, set return type to int
4916 as the frontend doesn't expect error_mark_node as
4918 TREE_TYPE (type) = integer_type_node;
4919 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4920 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4922 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4923 && TYPE_DECL_ALIAS_P (decl))
4924 ? DECL_ORIGINAL_TYPE (decl)
4925 : TREE_TYPE (decl)))
4927 TREE_TYPE (decl) = error_mark_node;
4928 return error_mark_node;
4932 return process_partial_specialization (decl);
4934 args = current_template_args ();
4937 || TREE_CODE (ctx) == FUNCTION_DECL
4938 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4939 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4941 if (DECL_LANG_SPECIFIC (decl)
4942 && DECL_TEMPLATE_INFO (decl)
4943 && DECL_TI_TEMPLATE (decl))
4944 tmpl = DECL_TI_TEMPLATE (decl);
4945 /* If DECL is a TYPE_DECL for a class-template, then there won't
4946 be DECL_LANG_SPECIFIC. The information equivalent to
4947 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4948 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4949 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4950 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4952 /* Since a template declaration already existed for this
4953 class-type, we must be redeclaring it here. Make sure
4954 that the redeclaration is valid. */
4955 redeclare_class_template (TREE_TYPE (decl),
4956 current_template_parms);
4957 /* We don't need to create a new TEMPLATE_DECL; just use the
4958 one we already had. */
4959 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4963 tmpl = build_template_decl (decl, current_template_parms,
4967 if (DECL_LANG_SPECIFIC (decl)
4968 && DECL_TEMPLATE_SPECIALIZATION (decl))
4970 /* A specialization of a member template of a template
4972 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4973 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4974 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4980 tree a, t, current, parms;
4982 tree tinfo = get_template_info (decl);
4986 error ("template definition of non-template %q#D", decl);
4987 return error_mark_node;
4990 tmpl = TI_TEMPLATE (tinfo);
4992 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4993 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4994 && DECL_TEMPLATE_SPECIALIZATION (decl)
4995 && DECL_MEMBER_TEMPLATE_P (tmpl))
4999 /* The declaration is a specialization of a member
5000 template, declared outside the class. Therefore, the
5001 innermost template arguments will be NULL, so we
5002 replace them with the arguments determined by the
5003 earlier call to check_explicit_specialization. */
5004 args = DECL_TI_ARGS (decl);
5007 = build_template_decl (decl, current_template_parms,
5009 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
5010 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
5011 DECL_TI_TEMPLATE (decl) = new_tmpl;
5012 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
5013 DECL_TEMPLATE_INFO (new_tmpl)
5014 = build_template_info (tmpl, args);
5016 register_specialization (new_tmpl,
5017 most_general_template (tmpl),
5023 /* Make sure the template headers we got make sense. */
5025 parms = DECL_TEMPLATE_PARMS (tmpl);
5026 i = TMPL_PARMS_DEPTH (parms);
5027 if (TMPL_ARGS_DEPTH (args) != i)
5029 error ("expected %d levels of template parms for %q#D, got %d",
5030 i, decl, TMPL_ARGS_DEPTH (args));
5033 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5035 a = TMPL_ARGS_LEVEL (args, i);
5036 t = INNERMOST_TEMPLATE_PARMS (parms);
5038 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5040 if (current == decl)
5041 error ("got %d template parameters for %q#D",
5042 TREE_VEC_LENGTH (a), decl);
5044 error ("got %d template parameters for %q#T",
5045 TREE_VEC_LENGTH (a), current);
5046 error (" but %d required", TREE_VEC_LENGTH (t));
5047 return error_mark_node;
5050 if (current == decl)
5052 else if (current == NULL_TREE)
5053 /* Can happen in erroneous input. */
5056 current = (TYPE_P (current)
5057 ? TYPE_CONTEXT (current)
5058 : DECL_CONTEXT (current));
5061 /* Check that the parms are used in the appropriate qualifying scopes
5062 in the declarator. */
5063 if (!comp_template_args
5065 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5068 template arguments to %qD do not match original template %qD",
5069 decl, DECL_TEMPLATE_RESULT (tmpl));
5070 if (!uses_template_parms (TI_ARGS (tinfo)))
5071 inform (input_location, "use template<> for an explicit specialization");
5072 /* Avoid crash in import_export_decl. */
5073 DECL_INTERFACE_KNOWN (decl) = 1;
5074 return error_mark_node;
5078 DECL_TEMPLATE_RESULT (tmpl) = decl;
5079 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5081 /* Push template declarations for global functions and types. Note
5082 that we do not try to push a global template friend declared in a
5083 template class; such a thing may well depend on the template
5084 parameters of the class. */
5085 if (new_template_p && !ctx
5086 && !(is_friend && template_class_depth (current_class_type) > 0))
5088 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5089 if (tmpl == error_mark_node)
5090 return error_mark_node;
5092 /* Hide template friend classes that haven't been declared yet. */
5093 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5095 DECL_ANTICIPATED (tmpl) = 1;
5096 DECL_FRIEND_P (tmpl) = 1;
5102 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5105 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5106 if (DECL_CONV_FN_P (tmpl))
5108 int depth = TMPL_PARMS_DEPTH (parms);
5110 /* It is a conversion operator. See if the type converted to
5111 depends on innermost template operands. */
5113 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5115 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5118 /* Give template template parms a DECL_CONTEXT of the template
5119 for which they are a parameter. */
5120 parms = INNERMOST_TEMPLATE_PARMS (parms);
5121 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5123 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5124 if (TREE_CODE (parm) == TEMPLATE_DECL)
5125 DECL_CONTEXT (parm) = tmpl;
5129 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5130 back to its most general template. If TMPL is a specialization,
5131 ARGS may only have the innermost set of arguments. Add the missing
5132 argument levels if necessary. */
5133 if (DECL_TEMPLATE_INFO (tmpl))
5134 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5136 info = build_template_info (tmpl, args);
5138 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5139 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5142 if (primary && !DECL_LANG_SPECIFIC (decl))
5143 retrofit_lang_decl (decl);
5144 if (DECL_LANG_SPECIFIC (decl))
5145 DECL_TEMPLATE_INFO (decl) = info;
5148 return DECL_TEMPLATE_RESULT (tmpl);
5152 push_template_decl (tree decl)
5154 return push_template_decl_real (decl, false);
5157 /* Called when a class template TYPE is redeclared with the indicated
5158 template PARMS, e.g.:
5160 template <class T> struct S;
5161 template <class T> struct S {}; */
5164 redeclare_class_template (tree type, tree parms)
5170 if (!TYPE_TEMPLATE_INFO (type))
5172 error ("%qT is not a template type", type);
5176 tmpl = TYPE_TI_TEMPLATE (type);
5177 if (!PRIMARY_TEMPLATE_P (tmpl))
5178 /* The type is nested in some template class. Nothing to worry
5179 about here; there are no new template parameters for the nested
5185 error ("template specifiers not specified in declaration of %qD",
5190 parms = INNERMOST_TEMPLATE_PARMS (parms);
5191 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5193 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5195 error_n (input_location, TREE_VEC_LENGTH (parms),
5196 "redeclared with %d template parameter",
5197 "redeclared with %d template parameters",
5198 TREE_VEC_LENGTH (parms));
5199 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5200 "previous declaration %q+D used %d template parameter",
5201 "previous declaration %q+D used %d template parameters",
5202 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5206 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5213 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5214 || TREE_VEC_ELT (parms, i) == error_mark_node)
5217 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5218 if (tmpl_parm == error_mark_node)
5221 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5222 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5223 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5225 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5227 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5228 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5229 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5230 || (TREE_CODE (tmpl_parm) != PARM_DECL
5231 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5232 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5233 || (TREE_CODE (tmpl_parm) == PARM_DECL
5234 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5235 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5237 error ("template parameter %q+#D", tmpl_parm);
5238 error ("redeclared here as %q#D", parm);
5242 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5244 /* We have in [temp.param]:
5246 A template-parameter may not be given default arguments
5247 by two different declarations in the same scope. */
5248 error_at (input_location, "redefinition of default argument for %q#D", parm);
5249 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5250 "original definition appeared here");
5254 if (parm_default != NULL_TREE)
5255 /* Update the previous template parameters (which are the ones
5256 that will really count) with the new default value. */
5257 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5258 else if (tmpl_default != NULL_TREE)
5259 /* Update the new parameters, too; they'll be used as the
5260 parameters for any members. */
5261 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5267 /* Simplify EXPR if it is a non-dependent expression. Returns the
5268 (possibly simplified) expression. */
5271 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5273 if (expr == NULL_TREE)
5276 /* If we're in a template, but EXPR isn't value dependent, simplify
5277 it. We're supposed to treat:
5279 template <typename T> void f(T[1 + 1]);
5280 template <typename T> void f(T[2]);
5282 as two declarations of the same function, for example. */
5283 if (processing_template_decl
5284 && !type_dependent_expression_p (expr)
5285 && potential_constant_expression (expr)
5286 && !value_dependent_expression_p (expr))
5288 HOST_WIDE_INT saved_processing_template_decl;
5290 saved_processing_template_decl = processing_template_decl;
5291 processing_template_decl = 0;
5292 expr = tsubst_copy_and_build (expr,
5295 /*in_decl=*/NULL_TREE,
5296 /*function_p=*/false,
5297 /*integral_constant_expression_p=*/true);
5298 processing_template_decl = saved_processing_template_decl;
5304 fold_non_dependent_expr (tree expr)
5306 return fold_non_dependent_expr_sfinae (expr, tf_error);
5309 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5310 template declaration, or a TYPE_DECL for an alias declaration. */
5313 alias_type_or_template_p (tree t)
5317 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5320 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5321 || DECL_ALIAS_TEMPLATE_P (t));
5324 /* Return TRUE iff is a specialization of an alias template. */
5327 alias_template_specialization_p (tree t)
5331 return (primary_template_instantiation_p (t)
5332 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5335 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5336 must be a function or a pointer-to-function type, as specified
5337 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5338 and check that the resulting function has external linkage. */
5341 convert_nontype_argument_function (tree type, tree expr)
5345 linkage_kind linkage;
5347 fn = instantiate_type (type, fns, tf_none);
5348 if (fn == error_mark_node)
5349 return error_mark_node;
5352 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5353 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5354 if (BASELINK_P (fn_no_ptr))
5355 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5357 /* [temp.arg.nontype]/1
5359 A template-argument for a non-type, non-template template-parameter
5362 -- the address of an object or function with external [C++11: or
5363 internal] linkage. */
5364 linkage = decl_linkage (fn_no_ptr);
5365 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5367 if (cxx_dialect >= cxx0x)
5368 error ("%qE is not a valid template argument for type %qT "
5369 "because %qD has no linkage",
5370 expr, type, fn_no_ptr);
5372 error ("%qE is not a valid template argument for type %qT "
5373 "because %qD does not have external linkage",
5374 expr, type, fn_no_ptr);
5381 /* Subroutine of convert_nontype_argument.
5382 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5383 Emit an error otherwise. */
5386 check_valid_ptrmem_cst_expr (tree type, tree expr,
5387 tsubst_flags_t complain)
5390 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5392 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5394 if (complain & tf_error)
5396 error ("%qE is not a valid template argument for type %qT",
5398 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5403 /* Returns TRUE iff the address of OP is value-dependent.
5405 14.6.2.4 [temp.dep.temp]:
5406 A non-integral non-type template-argument is dependent if its type is
5407 dependent or it has either of the following forms
5410 and contains a nested-name-specifier which specifies a class-name that
5411 names a dependent type.
5413 We generalize this to just say that the address of a member of a
5414 dependent class is value-dependent; the above doesn't cover the
5415 address of a static data member named with an unqualified-id. */
5418 has_value_dependent_address (tree op)
5420 /* We could use get_inner_reference here, but there's no need;
5421 this is only relevant for template non-type arguments, which
5422 can only be expressed as &id-expression. */
5425 tree ctx = CP_DECL_CONTEXT (op);
5426 if (TYPE_P (ctx) && dependent_type_p (ctx))
5433 /* The next set of functions are used for providing helpful explanatory
5434 diagnostics for failed overload resolution. Their messages should be
5435 indented by two spaces for consistency with the messages in
5439 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5445 unify_parameter_deduction_failure (bool explain_p, tree parm)
5448 inform (input_location,
5449 " couldn't deduce template parameter %qD", parm);
5454 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5460 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5463 inform (input_location,
5464 " types %qT and %qT have incompatible cv-qualifiers",
5470 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5473 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5478 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5481 inform (input_location,
5482 " template parameter %qD is not a parameter pack, but "
5489 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5492 inform (input_location,
5493 " template argument %qE does not match "
5494 "pointer-to-member constant %qE",
5500 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5503 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5508 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5511 inform (input_location,
5512 " inconsistent parameter pack deduction with %qT and %qT",
5518 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5523 inform (input_location,
5524 " deduced conflicting types for parameter %qT (%qT and %qT)",
5525 parm, first, second);
5527 inform (input_location,
5528 " deduced conflicting values for non-type parameter "
5529 "%qE (%qE and %qE)", parm, first, second);
5535 unify_vla_arg (bool explain_p, tree arg)
5538 inform (input_location,
5539 " variable-sized array type %qT is not "
5540 "a valid template argument",
5546 unify_method_type_error (bool explain_p, tree arg)
5549 inform (input_location,
5550 " member function type %qT is not a valid template argument",
5556 unify_arity (bool explain_p, int have, int wanted)
5559 inform_n (input_location, wanted,
5560 " candidate expects %d argument, %d provided",
5561 " candidate expects %d arguments, %d provided",
5567 unify_too_many_arguments (bool explain_p, int have, int wanted)
5569 return unify_arity (explain_p, have, wanted);
5573 unify_too_few_arguments (bool explain_p, int have, int wanted)
5575 return unify_arity (explain_p, have, wanted);
5579 unify_arg_conversion (bool explain_p, tree to_type,
5580 tree from_type, tree arg)
5583 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5584 arg, from_type, to_type);
5589 unify_no_common_base (bool explain_p, enum template_base_result r,
5590 tree parm, tree arg)
5595 case tbr_ambiguous_baseclass:
5596 inform (input_location, " %qT is an ambiguous base class of %qT",
5600 inform (input_location, " %qT is not derived from %qT", arg, parm);
5607 unify_inconsistent_template_template_parameters (bool explain_p)
5610 inform (input_location,
5611 " template parameters of a template template argument are "
5612 "inconsistent with other deduced template arguments");
5617 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5620 inform (input_location,
5621 " can't deduce a template for %qT from non-template type %qT",
5627 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5630 inform (input_location,
5631 " template argument %qE does not match %qD", arg, parm);
5636 unify_overload_resolution_failure (bool explain_p, tree arg)
5639 inform (input_location,
5640 " could not resolve address from overloaded function %qE",
5645 /* Attempt to convert the non-type template parameter EXPR to the
5646 indicated TYPE. If the conversion is successful, return the
5647 converted value. If the conversion is unsuccessful, return
5648 NULL_TREE if we issued an error message, or error_mark_node if we
5649 did not. We issue error messages for out-and-out bad template
5650 parameters, but not simply because the conversion failed, since we
5651 might be just trying to do argument deduction. Both TYPE and EXPR
5652 must be non-dependent.
5654 The conversion follows the special rules described in
5655 [temp.arg.nontype], and it is much more strict than an implicit
5658 This function is called twice for each template argument (see
5659 lookup_template_class for a more accurate description of this
5660 problem). This means that we need to handle expressions which
5661 are not valid in a C++ source, but can be created from the
5662 first call (for instance, casts to perform conversions). These
5663 hacks can go away after we fix the double coercion problem. */
5666 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5670 /* Detect immediately string literals as invalid non-type argument.
5671 This special-case is not needed for correctness (we would easily
5672 catch this later), but only to provide better diagnostic for this
5673 common user mistake. As suggested by DR 100, we do not mention
5674 linkage issues in the diagnostic as this is not the point. */
5675 /* FIXME we're making this OK. */
5676 if (TREE_CODE (expr) == STRING_CST)
5678 if (complain & tf_error)
5679 error ("%qE is not a valid template argument for type %qT "
5680 "because string literals can never be used in this context",
5685 /* Add the ADDR_EXPR now for the benefit of
5686 value_dependent_expression_p. */
5687 if (TYPE_PTROBV_P (type)
5688 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5689 expr = decay_conversion (expr);
5691 /* If we are in a template, EXPR may be non-dependent, but still
5692 have a syntactic, rather than semantic, form. For example, EXPR
5693 might be a SCOPE_REF, rather than the VAR_DECL to which the
5694 SCOPE_REF refers. Preserving the qualifying scope is necessary
5695 so that access checking can be performed when the template is
5696 instantiated -- but here we need the resolved form so that we can
5697 convert the argument. */
5698 if (TYPE_REF_OBJ_P (type)
5699 && has_value_dependent_address (expr))
5700 /* If we want the address and it's value-dependent, don't fold. */;
5701 else if (!type_unknown_p (expr))
5702 expr = fold_non_dependent_expr_sfinae (expr, complain);
5703 if (error_operand_p (expr))
5704 return error_mark_node;
5705 expr_type = TREE_TYPE (expr);
5706 if (TREE_CODE (type) == REFERENCE_TYPE)
5707 expr = mark_lvalue_use (expr);
5709 expr = mark_rvalue_use (expr);
5711 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5712 to a non-type argument of "nullptr". */
5713 if (expr == nullptr_node
5714 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5715 expr = convert (type, expr);
5717 /* In C++11, integral or enumeration non-type template arguments can be
5718 arbitrary constant expressions. Pointer and pointer to
5719 member arguments can be general constant expressions that evaluate
5720 to a null value, but otherwise still need to be of a specific form. */
5721 if (cxx_dialect >= cxx0x)
5723 if (TREE_CODE (expr) == PTRMEM_CST)
5724 /* A PTRMEM_CST is already constant, and a valid template
5725 argument for a parameter of pointer to member type, we just want
5726 to leave it in that form rather than lower it to a
5728 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5729 expr = maybe_constant_value (expr);
5730 else if (TYPE_PTR_P (type)
5731 || TYPE_PTR_TO_MEMBER_P (type))
5733 tree folded = maybe_constant_value (expr);
5734 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5735 : null_member_pointer_value_p (folded))
5740 /* HACK: Due to double coercion, we can get a
5741 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5742 which is the tree that we built on the first call (see
5743 below when coercing to reference to object or to reference to
5744 function). We just strip everything and get to the arg.
5745 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5747 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5749 tree probe_type, probe = expr;
5750 if (REFERENCE_REF_P (probe))
5751 probe = TREE_OPERAND (probe, 0);
5752 probe_type = TREE_TYPE (probe);
5753 if (TREE_CODE (probe) == NOP_EXPR)
5755 /* ??? Maybe we could use convert_from_reference here, but we
5756 would need to relax its constraints because the NOP_EXPR
5757 could actually change the type to something more cv-qualified,
5758 and this is not folded by convert_from_reference. */
5759 tree addr = TREE_OPERAND (probe, 0);
5760 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5761 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5762 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5763 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5764 (TREE_TYPE (probe_type),
5765 TREE_TYPE (TREE_TYPE (addr))));
5767 expr = TREE_OPERAND (addr, 0);
5768 expr_type = TREE_TYPE (expr);
5772 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5773 parameter is a pointer to object, through decay and
5774 qualification conversion. Let's strip everything. */
5775 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5778 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5779 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5780 /* Skip the ADDR_EXPR only if it is part of the decay for
5781 an array. Otherwise, it is part of the original argument
5782 in the source code. */
5783 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5784 expr = TREE_OPERAND (expr, 0);
5785 expr_type = TREE_TYPE (expr);
5788 /* [temp.arg.nontype]/5, bullet 1
5790 For a non-type template-parameter of integral or enumeration type,
5791 integral promotions (_conv.prom_) and integral conversions
5792 (_conv.integral_) are applied. */
5793 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5795 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5796 t = maybe_constant_value (t);
5797 if (t != error_mark_node)
5800 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5801 return error_mark_node;
5803 /* Notice that there are constant expressions like '4 % 0' which
5804 do not fold into integer constants. */
5805 if (TREE_CODE (expr) != INTEGER_CST)
5807 if (complain & tf_error)
5809 int errs = errorcount, warns = warningcount;
5810 expr = cxx_constant_value (expr);
5811 if (errorcount > errs || warningcount > warns)
5812 inform (EXPR_LOC_OR_HERE (expr),
5813 "in template argument for type %qT ", type);
5814 if (expr == error_mark_node)
5816 /* else cxx_constant_value complained but gave us
5817 a real constant, so go ahead. */
5818 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5824 /* [temp.arg.nontype]/5, bullet 2
5826 For a non-type template-parameter of type pointer to object,
5827 qualification conversions (_conv.qual_) and the array-to-pointer
5828 conversion (_conv.array_) are applied. */
5829 else if (TYPE_PTROBV_P (type))
5831 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5833 A template-argument for a non-type, non-template template-parameter
5834 shall be one of: [...]
5836 -- the name of a non-type template-parameter;
5837 -- the address of an object or function with external linkage, [...]
5838 expressed as "& id-expression" where the & is optional if the name
5839 refers to a function or array, or if the corresponding
5840 template-parameter is a reference.
5842 Here, we do not care about functions, as they are invalid anyway
5843 for a parameter of type pointer-to-object. */
5845 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5846 /* Non-type template parameters are OK. */
5848 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5849 /* Null pointer values are OK in C++11. */;
5850 else if (TREE_CODE (expr) != ADDR_EXPR
5851 && TREE_CODE (expr_type) != ARRAY_TYPE)
5853 if (TREE_CODE (expr) == VAR_DECL)
5855 error ("%qD is not a valid template argument "
5856 "because %qD is a variable, not the address of "
5861 /* Other values, like integer constants, might be valid
5862 non-type arguments of some other type. */
5863 return error_mark_node;
5869 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5870 ? TREE_OPERAND (expr, 0) : expr);
5871 if (TREE_CODE (decl) != VAR_DECL)
5873 error ("%qE is not a valid template argument of type %qT "
5874 "because %qE is not a variable",
5878 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5880 error ("%qE is not a valid template argument of type %qT "
5881 "because %qD does not have external linkage",
5885 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5887 error ("%qE is not a valid template argument of type %qT "
5888 "because %qD has no linkage",
5894 expr = decay_conversion (expr);
5895 if (expr == error_mark_node)
5896 return error_mark_node;
5898 expr = perform_qualification_conversions (type, expr);
5899 if (expr == error_mark_node)
5900 return error_mark_node;
5902 /* [temp.arg.nontype]/5, bullet 3
5904 For a non-type template-parameter of type reference to object, no
5905 conversions apply. The type referred to by the reference may be more
5906 cv-qualified than the (otherwise identical) type of the
5907 template-argument. The template-parameter is bound directly to the
5908 template-argument, which must be an lvalue. */
5909 else if (TYPE_REF_OBJ_P (type))
5911 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5913 return error_mark_node;
5915 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5917 error ("%qE is not a valid template argument for type %qT "
5918 "because of conflicts in cv-qualification", expr, type);
5922 if (!real_lvalue_p (expr))
5924 error ("%qE is not a valid template argument for type %qT "
5925 "because it is not an lvalue", expr, type);
5929 /* [temp.arg.nontype]/1
5931 A template-argument for a non-type, non-template template-parameter
5932 shall be one of: [...]
5934 -- the address of an object or function with external linkage. */
5935 if (TREE_CODE (expr) == INDIRECT_REF
5936 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5938 expr = TREE_OPERAND (expr, 0);
5941 error ("%q#D is not a valid template argument for type %qT "
5942 "because a reference variable does not have a constant "
5943 "address", expr, type);
5950 error ("%qE is not a valid template argument for type %qT "
5951 "because it is not an object with external linkage",
5956 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5958 error ("%qE is not a valid template argument for type %qT "
5959 "because object %qD has not external linkage",
5964 expr = build_nop (type, build_address (expr));
5966 /* [temp.arg.nontype]/5, bullet 4
5968 For a non-type template-parameter of type pointer to function, only
5969 the function-to-pointer conversion (_conv.func_) is applied. If the
5970 template-argument represents a set of overloaded functions (or a
5971 pointer to such), the matching function is selected from the set
5973 else if (TYPE_PTRFN_P (type))
5975 /* If the argument is a template-id, we might not have enough
5976 context information to decay the pointer. */
5977 if (!type_unknown_p (expr_type))
5979 expr = decay_conversion (expr);
5980 if (expr == error_mark_node)
5981 return error_mark_node;
5984 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5985 /* Null pointer values are OK in C++11. */
5986 return perform_qualification_conversions (type, expr);
5988 expr = convert_nontype_argument_function (type, expr);
5989 if (!expr || expr == error_mark_node)
5992 if (TREE_CODE (expr) != ADDR_EXPR)
5994 error ("%qE is not a valid template argument for type %qT", expr, type);
5995 error ("it must be the address of a function with external linkage");
5999 /* [temp.arg.nontype]/5, bullet 5
6001 For a non-type template-parameter of type reference to function, no
6002 conversions apply. If the template-argument represents a set of
6003 overloaded functions, the matching function is selected from the set
6005 else if (TYPE_REFFN_P (type))
6007 if (TREE_CODE (expr) == ADDR_EXPR)
6009 error ("%qE is not a valid template argument for type %qT "
6010 "because it is a pointer", expr, type);
6011 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
6015 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
6016 if (!expr || expr == error_mark_node)
6019 expr = build_nop (type, build_address (expr));
6021 /* [temp.arg.nontype]/5, bullet 6
6023 For a non-type template-parameter of type pointer to member function,
6024 no conversions apply. If the template-argument represents a set of
6025 overloaded member functions, the matching member function is selected
6026 from the set (_over.over_). */
6027 else if (TYPE_PTRMEMFUNC_P (type))
6029 expr = instantiate_type (type, expr, tf_none);
6030 if (expr == error_mark_node)
6031 return error_mark_node;
6033 /* [temp.arg.nontype] bullet 1 says the pointer to member
6034 expression must be a pointer-to-member constant. */
6035 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6036 return error_mark_node;
6038 /* There is no way to disable standard conversions in
6039 resolve_address_of_overloaded_function (called by
6040 instantiate_type). It is possible that the call succeeded by
6041 converting &B::I to &D::I (where B is a base of D), so we need
6042 to reject this conversion here.
6044 Actually, even if there was a way to disable standard conversions,
6045 it would still be better to reject them here so that we can
6046 provide a superior diagnostic. */
6047 if (!same_type_p (TREE_TYPE (expr), type))
6049 error ("%qE is not a valid template argument for type %qT "
6050 "because it is of type %qT", expr, type,
6052 /* If we are just one standard conversion off, explain. */
6053 if (can_convert (type, TREE_TYPE (expr)))
6054 inform (input_location,
6055 "standard conversions are not allowed in this context");
6059 /* [temp.arg.nontype]/5, bullet 7
6061 For a non-type template-parameter of type pointer to data member,
6062 qualification conversions (_conv.qual_) are applied. */
6063 else if (TYPE_PTRMEM_P (type))
6065 /* [temp.arg.nontype] bullet 1 says the pointer to member
6066 expression must be a pointer-to-member constant. */
6067 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6068 return error_mark_node;
6070 expr = perform_qualification_conversions (type, expr);
6071 if (expr == error_mark_node)
6074 else if (NULLPTR_TYPE_P (type))
6076 if (expr != nullptr_node)
6078 error ("%qE is not a valid template argument for type %qT "
6079 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6084 /* A template non-type parameter must be one of the above. */
6088 /* Sanity check: did we actually convert the argument to the
6090 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6091 (type, TREE_TYPE (expr)));
6095 /* Subroutine of coerce_template_template_parms, which returns 1 if
6096 PARM_PARM and ARG_PARM match using the rule for the template
6097 parameters of template template parameters. Both PARM and ARG are
6098 template parameters; the rest of the arguments are the same as for
6099 coerce_template_template_parms.
6102 coerce_template_template_parm (tree parm,
6104 tsubst_flags_t complain,
6108 if (arg == NULL_TREE || arg == error_mark_node
6109 || parm == NULL_TREE || parm == error_mark_node)
6112 if (TREE_CODE (arg) != TREE_CODE (parm))
6115 switch (TREE_CODE (parm))
6118 /* We encounter instantiations of templates like
6119 template <template <template <class> class> class TT>
6122 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6123 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6125 if (!coerce_template_template_parms
6126 (parmparm, argparm, complain, in_decl, outer_args))
6132 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6133 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6134 /* Argument is a parameter pack but parameter is not. */
6139 /* The tsubst call is used to handle cases such as
6141 template <int> class C {};
6142 template <class T, template <T> class TT> class D {};
6145 i.e. the parameter list of TT depends on earlier parameters. */
6146 if (!uses_template_parms (TREE_TYPE (arg))
6148 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6152 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6153 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6154 /* Argument is a parameter pack but parameter is not. */
6167 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6168 template template parameters. Both PARM_PARMS and ARG_PARMS are
6169 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6172 Consider the example:
6173 template <class T> class A;
6174 template<template <class U> class TT> class B;
6176 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6177 the parameters to A, and OUTER_ARGS contains A. */
6180 coerce_template_template_parms (tree parm_parms,
6182 tsubst_flags_t complain,
6186 int nparms, nargs, i;
6190 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6191 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6193 nparms = TREE_VEC_LENGTH (parm_parms);
6194 nargs = TREE_VEC_LENGTH (arg_parms);
6196 /* Determine whether we have a parameter pack at the end of the
6197 template template parameter's template parameter list. */
6198 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6200 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6202 if (parm == error_mark_node)
6205 switch (TREE_CODE (parm))
6209 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6214 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6224 && !(variadic_p && nargs >= nparms - 1))
6227 /* Check all of the template parameters except the parameter pack at
6228 the end (if any). */
6229 for (i = 0; i < nparms - variadic_p; ++i)
6231 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6232 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6235 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6236 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6238 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6246 /* Check each of the template parameters in the template
6247 argument against the template parameter pack at the end of
6248 the template template parameter. */
6249 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6252 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6254 for (; i < nargs; ++i)
6256 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6259 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6261 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6270 /* Verifies that the deduced template arguments (in TARGS) for the
6271 template template parameters (in TPARMS) represent valid bindings,
6272 by comparing the template parameter list of each template argument
6273 to the template parameter list of its corresponding template
6274 template parameter, in accordance with DR150. This
6275 routine can only be called after all template arguments have been
6276 deduced. It will return TRUE if all of the template template
6277 parameter bindings are okay, FALSE otherwise. */
6279 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6281 int i, ntparms = TREE_VEC_LENGTH (tparms);
6284 /* We're dealing with template parms in this process. */
6285 ++processing_template_decl;
6287 targs = INNERMOST_TEMPLATE_ARGS (targs);
6289 for (i = 0; i < ntparms; ++i)
6291 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6292 tree targ = TREE_VEC_ELT (targs, i);
6294 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6296 tree packed_args = NULL_TREE;
6299 if (ARGUMENT_PACK_P (targ))
6301 /* Look inside the argument pack. */
6302 packed_args = ARGUMENT_PACK_ARGS (targ);
6303 len = TREE_VEC_LENGTH (packed_args);
6306 for (idx = 0; idx < len; ++idx)
6308 tree targ_parms = NULL_TREE;
6311 /* Extract the next argument from the argument
6313 targ = TREE_VEC_ELT (packed_args, idx);
6315 if (PACK_EXPANSION_P (targ))
6316 /* Look at the pattern of the pack expansion. */
6317 targ = PACK_EXPANSION_PATTERN (targ);
6319 /* Extract the template parameters from the template
6321 if (TREE_CODE (targ) == TEMPLATE_DECL)
6322 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6323 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6324 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6326 /* Verify that we can coerce the template template
6327 parameters from the template argument to the template
6328 parameter. This requires an exact match. */
6330 && !coerce_template_template_parms
6331 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6346 --processing_template_decl;
6350 /* Since type attributes aren't mangled, we need to strip them from
6351 template type arguments. */
6354 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6357 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6359 mv = TYPE_MAIN_VARIANT (arg);
6360 arg = strip_typedefs (arg);
6361 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6362 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6364 if (complain & tf_warning)
6365 warning (0, "ignoring attributes on template argument %qT", arg);
6366 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6367 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6372 /* Convert the indicated template ARG as necessary to match the
6373 indicated template PARM. Returns the converted ARG, or
6374 error_mark_node if the conversion was unsuccessful. Error and
6375 warning messages are issued under control of COMPLAIN. This
6376 conversion is for the Ith parameter in the parameter list. ARGS is
6377 the full set of template arguments deduced so far. */
6380 convert_template_argument (tree parm,
6383 tsubst_flags_t complain,
6389 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6391 if (TREE_CODE (arg) == TREE_LIST
6392 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6394 /* The template argument was the name of some
6395 member function. That's usually
6396 invalid, but static members are OK. In any
6397 case, grab the underlying fields/functions
6398 and issue an error later if required. */
6399 orig_arg = TREE_VALUE (arg);
6400 TREE_TYPE (arg) = unknown_type_node;
6405 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6406 requires_type = (TREE_CODE (parm) == TYPE_DECL
6407 || requires_tmpl_type);
6409 /* When determining whether an argument pack expansion is a template,
6410 look at the pattern. */
6411 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6412 arg = PACK_EXPANSION_PATTERN (arg);
6414 /* Deal with an injected-class-name used as a template template arg. */
6415 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6417 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6418 if (TREE_CODE (t) == TEMPLATE_DECL)
6420 if (cxx_dialect >= cxx0x)
6421 /* OK under DR 1004. */;
6422 else if (complain & tf_warning_or_error)
6423 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6424 " used as template template argument", TYPE_NAME (arg));
6425 else if (flag_pedantic_errors)
6433 ((TREE_CODE (arg) == TEMPLATE_DECL
6434 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6435 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6436 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6439 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6440 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6441 arg = TYPE_STUB_DECL (arg);
6443 is_type = TYPE_P (arg) || is_tmpl_type;
6445 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6446 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6448 permerror (input_location, "to refer to a type member of a template parameter, "
6449 "use %<typename %E%>", orig_arg);
6451 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6452 TREE_OPERAND (arg, 1),
6454 complain & tf_error);
6458 if (is_type != requires_type)
6462 if (complain & tf_error)
6464 error ("type/value mismatch at argument %d in template "
6465 "parameter list for %qD",
6468 error (" expected a constant of type %qT, got %qT",
6470 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6471 else if (requires_tmpl_type)
6472 error (" expected a class template, got %qE", orig_arg);
6474 error (" expected a type, got %qE", orig_arg);
6477 return error_mark_node;
6479 if (is_tmpl_type ^ requires_tmpl_type)
6481 if (in_decl && (complain & tf_error))
6483 error ("type/value mismatch at argument %d in template "
6484 "parameter list for %qD",
6487 error (" expected a type, got %qT", DECL_NAME (arg));
6489 error (" expected a class template, got %qT", orig_arg);
6491 return error_mark_node;
6496 if (requires_tmpl_type)
6498 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6499 /* The number of argument required is not known yet.
6500 Just accept it for now. */
6501 val = TREE_TYPE (arg);
6504 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6507 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6509 if (coerce_template_template_parms (parmparm, argparm,
6515 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6517 if (val != error_mark_node)
6519 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6520 val = TREE_TYPE (val);
6521 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6522 val = make_pack_expansion (val);
6527 if (in_decl && (complain & tf_error))
6529 error ("type/value mismatch at argument %d in "
6530 "template parameter list for %qD",
6532 error (" expected a template of type %qD, got %qT",
6536 val = error_mark_node;
6542 /* We only form one instance of each template specialization.
6543 Therefore, if we use a non-canonical variant (i.e., a
6544 typedef), any future messages referring to the type will use
6545 the typedef, which is confusing if those future uses do not
6546 themselves also use the typedef. */
6548 val = canonicalize_type_argument (val, complain);
6552 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6554 if (invalid_nontype_parm_type_p (t, complain))
6555 return error_mark_node;
6557 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6559 if (same_type_p (t, TREE_TYPE (orig_arg)))
6563 /* Not sure if this is reachable, but it doesn't hurt
6565 error ("type mismatch in nontype parameter pack");
6566 val = error_mark_node;
6569 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6570 /* We used to call digest_init here. However, digest_init
6571 will report errors, which we don't want when complain
6572 is zero. More importantly, digest_init will try too
6573 hard to convert things: for example, `0' should not be
6574 converted to pointer type at this point according to
6575 the standard. Accepting this is not merely an
6576 extension, since deciding whether or not these
6577 conversions can occur is part of determining which
6578 function template to call, or whether a given explicit
6579 argument specification is valid. */
6580 val = convert_nontype_argument (t, orig_arg, complain);
6584 if (val == NULL_TREE)
6585 val = error_mark_node;
6586 else if (val == error_mark_node && (complain & tf_error))
6587 error ("could not convert template argument %qE to %qT", orig_arg, t);
6589 if (TREE_CODE (val) == SCOPE_REF)
6591 /* Strip typedefs from the SCOPE_REF. */
6592 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6593 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6595 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6596 QUALIFIED_NAME_IS_TEMPLATE (val));
6603 /* Coerces the remaining template arguments in INNER_ARGS (from
6604 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6605 Returns the coerced argument pack. PARM_IDX is the position of this
6606 parameter in the template parameter list. ARGS is the original
6607 template argument list. */
6609 coerce_template_parameter_pack (tree parms,
6617 tsubst_flags_t complain)
6619 tree parm = TREE_VEC_ELT (parms, parm_idx);
6620 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6623 tree packed_types = NULL_TREE;
6625 if (arg_idx > nargs)
6628 packed_args = make_tree_vec (nargs - arg_idx);
6630 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6631 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6633 /* When the template parameter is a non-type template
6634 parameter pack whose type uses parameter packs, we need
6635 to look at each of the template arguments
6636 separately. Build a vector of the types for these
6637 non-type template parameters in PACKED_TYPES. */
6639 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6640 packed_types = tsubst_pack_expansion (expansion, args,
6643 if (packed_types == error_mark_node)
6644 return error_mark_node;
6646 /* Check that we have the right number of arguments. */
6648 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6649 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6652 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6653 error ("wrong number of template arguments (%d, should be %d)",
6654 nargs, needed_parms);
6655 return error_mark_node;
6658 /* If we aren't able to check the actual arguments now
6659 (because they haven't been expanded yet), we can at least
6660 verify that all of the types used for the non-type
6661 template parameter pack are, in fact, valid for non-type
6662 template parameters. */
6664 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6666 int j, len = TREE_VEC_LENGTH (packed_types);
6667 for (j = 0; j < len; ++j)
6669 tree t = TREE_VEC_ELT (packed_types, j);
6670 if (invalid_nontype_parm_type_p (t, complain))
6671 return error_mark_node;
6676 /* Convert the remaining arguments, which will be a part of the
6677 parameter pack "parm". */
6678 for (; arg_idx < nargs; ++arg_idx)
6680 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6681 tree actual_parm = TREE_VALUE (parm);
6683 if (packed_types && !PACK_EXPANSION_P (arg))
6685 /* When we have a vector of types (corresponding to the
6686 non-type template parameter pack that uses parameter
6687 packs in its type, as mention above), and the
6688 argument is not an expansion (which expands to a
6689 currently unknown number of arguments), clone the
6690 parm and give it the next type in PACKED_TYPES. */
6691 actual_parm = copy_node (actual_parm);
6692 TREE_TYPE (actual_parm) =
6693 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6696 if (arg != error_mark_node)
6697 arg = convert_template_argument (actual_parm,
6698 arg, new_args, complain, parm_idx,
6700 if (arg == error_mark_node)
6702 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6705 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6706 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6707 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6710 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6711 TREE_TYPE (argument_pack)
6712 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6713 TREE_CONSTANT (argument_pack) = 1;
6716 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6717 #ifdef ENABLE_CHECKING
6718 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6719 TREE_VEC_LENGTH (packed_args));
6721 return argument_pack;
6724 /* Convert all template arguments to their appropriate types, and
6725 return a vector containing the innermost resulting template
6726 arguments. If any error occurs, return error_mark_node. Error and
6727 warning messages are issued under control of COMPLAIN.
6729 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6730 for arguments not specified in ARGS. Otherwise, if
6731 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6732 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6733 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6737 coerce_template_parms (tree parms,
6740 tsubst_flags_t complain,
6741 bool require_all_args,
6742 bool use_default_args)
6744 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6747 tree new_inner_args;
6748 int saved_unevaluated_operand;
6749 int saved_inhibit_evaluation_warnings;
6751 /* When used as a boolean value, indicates whether this is a
6752 variadic template parameter list. Since it's an int, we can also
6753 subtract it from nparms to get the number of non-variadic
6756 int post_variadic_parms = 0;
6758 if (args == error_mark_node)
6759 return error_mark_node;
6761 nparms = TREE_VEC_LENGTH (parms);
6763 /* Determine if there are any parameter packs. */
6764 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6766 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6768 ++post_variadic_parms;
6769 if (template_parameter_pack_p (tparm))
6773 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6774 /* If there are no parameters that follow a parameter pack, we need to
6775 expand any argument packs so that we can deduce a parameter pack from
6776 some non-packed args followed by an argument pack, as in variadic85.C.
6777 If there are such parameters, we need to leave argument packs intact
6778 so the arguments are assigned properly. This can happen when dealing
6779 with a nested class inside a partial specialization of a class
6780 template, as in variadic92.C, or when deducing a template parameter pack
6781 from a sub-declarator, as in variadic114.C. */
6782 if (!post_variadic_parms)
6783 inner_args = expand_template_argument_pack (inner_args);
6785 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6786 if ((nargs > nparms && !variadic_p)
6787 || (nargs < nparms - variadic_p
6789 && (!use_default_args
6790 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6791 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6793 if (complain & tf_error)
6797 nparms -= variadic_p;
6798 error ("wrong number of template arguments "
6799 "(%d, should be %d or more)", nargs, nparms);
6802 error ("wrong number of template arguments "
6803 "(%d, should be %d)", nargs, nparms);
6806 error ("provided for %q+D", in_decl);
6809 return error_mark_node;
6812 /* We need to evaluate the template arguments, even though this
6813 template-id may be nested within a "sizeof". */
6814 saved_unevaluated_operand = cp_unevaluated_operand;
6815 cp_unevaluated_operand = 0;
6816 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6817 c_inhibit_evaluation_warnings = 0;
6818 new_inner_args = make_tree_vec (nparms);
6819 new_args = add_outermost_template_args (args, new_inner_args);
6820 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6825 /* Get the Ith template parameter. */
6826 parm = TREE_VEC_ELT (parms, parm_idx);
6828 if (parm == error_mark_node)
6830 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6834 /* Calculate the next argument. */
6835 if (arg_idx < nargs)
6836 arg = TREE_VEC_ELT (inner_args, arg_idx);
6840 if (template_parameter_pack_p (TREE_VALUE (parm))
6841 && !(arg && ARGUMENT_PACK_P (arg)))
6843 /* All remaining arguments will be placed in the
6844 template parameter pack PARM. */
6845 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6846 inner_args, arg_idx,
6850 /* Store this argument. */
6851 if (arg == error_mark_node)
6853 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6855 /* We are done with all of the arguments. */
6862 if (PACK_EXPANSION_P (arg))
6864 /* We don't know how many args we have yet, just
6865 use the unconverted ones for now. */
6866 new_inner_args = args;
6870 else if (require_all_args)
6872 /* There must be a default arg in this case. */
6873 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6875 /* The position of the first default template argument,
6876 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6878 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6879 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6884 if (arg == error_mark_node)
6886 if (complain & tf_error)
6887 error ("template argument %d is invalid", arg_idx + 1);
6890 /* This only occurs if there was an error in the template
6891 parameter list itself (which we would already have
6892 reported) that we are trying to recover from, e.g., a class
6893 template with a parameter list such as
6894 template<typename..., typename>. */
6897 arg = convert_template_argument (TREE_VALUE (parm),
6898 arg, new_args, complain,
6901 if (arg == error_mark_node)
6903 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6905 cp_unevaluated_operand = saved_unevaluated_operand;
6906 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6909 return error_mark_node;
6911 #ifdef ENABLE_CHECKING
6912 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6913 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6914 TREE_VEC_LENGTH (new_inner_args));
6917 return new_inner_args;
6920 /* Returns 1 if template args OT and NT are equivalent. */
6923 template_args_equal (tree ot, tree nt)
6927 if (nt == NULL_TREE || ot == NULL_TREE)
6930 if (TREE_CODE (nt) == TREE_VEC)
6931 /* For member templates */
6932 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6933 else if (PACK_EXPANSION_P (ot))
6934 return (PACK_EXPANSION_P (nt)
6935 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6936 PACK_EXPANSION_PATTERN (nt))
6937 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6938 PACK_EXPANSION_EXTRA_ARGS (nt)));
6939 else if (ARGUMENT_PACK_P (ot))
6944 if (!ARGUMENT_PACK_P (nt))
6947 opack = ARGUMENT_PACK_ARGS (ot);
6948 npack = ARGUMENT_PACK_ARGS (nt);
6949 len = TREE_VEC_LENGTH (opack);
6950 if (TREE_VEC_LENGTH (npack) != len)
6952 for (i = 0; i < len; ++i)
6953 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6954 TREE_VEC_ELT (npack, i)))
6958 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6960 /* We get here probably because we are in the middle of substituting
6961 into the pattern of a pack expansion. In that case the
6962 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6963 interested in. So we want to use the initial pack argument for
6965 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6966 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6967 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6968 return template_args_equal (ot, nt);
6970 else if (TYPE_P (nt))
6971 return TYPE_P (ot) && same_type_p (ot, nt);
6972 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6975 return cp_tree_equal (ot, nt);
6978 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6979 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6980 NEWARG_PTR with the offending arguments if they are non-NULL. */
6983 comp_template_args_with_info (tree oldargs, tree newargs,
6984 tree *oldarg_ptr, tree *newarg_ptr)
6988 if (oldargs == newargs)
6991 if (!oldargs || !newargs)
6994 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6997 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6999 tree nt = TREE_VEC_ELT (newargs, i);
7000 tree ot = TREE_VEC_ELT (oldargs, i);
7002 if (! template_args_equal (ot, nt))
7004 if (oldarg_ptr != NULL)
7006 if (newarg_ptr != NULL)
7014 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
7015 of template arguments. Returns 0 otherwise. */
7018 comp_template_args (tree oldargs, tree newargs)
7020 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
7024 add_pending_template (tree d)
7026 tree ti = (TYPE_P (d)
7027 ? CLASSTYPE_TEMPLATE_INFO (d)
7028 : DECL_TEMPLATE_INFO (d));
7029 struct pending_template *pt;
7032 if (TI_PENDING_TEMPLATE_FLAG (ti))
7035 /* We are called both from instantiate_decl, where we've already had a
7036 tinst_level pushed, and instantiate_template, where we haven't.
7038 level = !current_tinst_level || current_tinst_level->decl != d;
7041 push_tinst_level (d);
7043 pt = ggc_alloc_pending_template ();
7045 pt->tinst = current_tinst_level;
7046 if (last_pending_template)
7047 last_pending_template->next = pt;
7049 pending_templates = pt;
7051 last_pending_template = pt;
7053 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7060 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7061 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7062 documentation for TEMPLATE_ID_EXPR. */
7065 lookup_template_function (tree fns, tree arglist)
7069 if (fns == error_mark_node || arglist == error_mark_node)
7070 return error_mark_node;
7072 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7074 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7076 error ("%q#D is not a function template", fns);
7077 return error_mark_node;
7080 if (BASELINK_P (fns))
7082 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7084 BASELINK_FUNCTIONS (fns),
7089 type = TREE_TYPE (fns);
7090 if (TREE_CODE (fns) == OVERLOAD || !type)
7091 type = unknown_type_node;
7093 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7096 /* Within the scope of a template class S<T>, the name S gets bound
7097 (in build_self_reference) to a TYPE_DECL for the class, not a
7098 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7099 or one of its enclosing classes, and that type is a template,
7100 return the associated TEMPLATE_DECL. Otherwise, the original
7103 Also handle the case when DECL is a TREE_LIST of ambiguous
7104 injected-class-names from different bases. */
7107 maybe_get_template_decl_from_type_decl (tree decl)
7109 if (decl == NULL_TREE)
7112 /* DR 176: A lookup that finds an injected-class-name (10.2
7113 [class.member.lookup]) can result in an ambiguity in certain cases
7114 (for example, if it is found in more than one base class). If all of
7115 the injected-class-names that are found refer to specializations of
7116 the same class template, and if the name is followed by a
7117 template-argument-list, the reference refers to the class template
7118 itself and not a specialization thereof, and is not ambiguous. */
7119 if (TREE_CODE (decl) == TREE_LIST)
7121 tree t, tmpl = NULL_TREE;
7122 for (t = decl; t; t = TREE_CHAIN (t))
7124 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7127 else if (tmpl != elt)
7130 if (tmpl && t == NULL_TREE)
7136 return (decl != NULL_TREE
7137 && DECL_SELF_REFERENCE_P (decl)
7138 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7139 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7142 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7143 parameters, find the desired type.
7145 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7147 IN_DECL, if non-NULL, is the template declaration we are trying to
7150 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7151 the class we are looking up.
7153 Issue error and warning messages under control of COMPLAIN.
7155 If the template class is really a local class in a template
7156 function, then the FUNCTION_CONTEXT is the function in which it is
7159 ??? Note that this function is currently called *twice* for each
7160 template-id: the first time from the parser, while creating the
7161 incomplete type (finish_template_type), and the second type during the
7162 real instantiation (instantiate_template_class). This is surely something
7163 that we want to avoid. It also causes some problems with argument
7164 coercion (see convert_nontype_argument for more information on this). */
7167 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7168 int entering_scope, tsubst_flags_t complain)
7170 tree templ = NULL_TREE, parmlist;
7177 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7179 tree value = innermost_non_namespace_value (d1);
7180 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7185 push_decl_namespace (context);
7186 templ = lookup_name (d1);
7187 templ = maybe_get_template_decl_from_type_decl (templ);
7189 pop_decl_namespace ();
7192 context = DECL_CONTEXT (templ);
7194 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7196 tree type = TREE_TYPE (d1);
7198 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7199 an implicit typename for the second A. Deal with it. */
7200 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7201 type = TREE_TYPE (type);
7203 if (CLASSTYPE_TEMPLATE_INFO (type))
7205 templ = CLASSTYPE_TI_TEMPLATE (type);
7206 d1 = DECL_NAME (templ);
7209 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7210 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7212 templ = TYPE_TI_TEMPLATE (d1);
7213 d1 = DECL_NAME (templ);
7215 else if (TREE_CODE (d1) == TEMPLATE_DECL
7216 && DECL_TEMPLATE_RESULT (d1)
7217 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7220 d1 = DECL_NAME (templ);
7221 context = DECL_CONTEXT (templ);
7224 /* Issue an error message if we didn't find a template. */
7227 if (complain & tf_error)
7228 error ("%qT is not a template", d1);
7229 return error_mark_node;
7232 if (TREE_CODE (templ) != TEMPLATE_DECL
7233 /* Make sure it's a user visible template, if it was named by
7235 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7236 && !PRIMARY_TEMPLATE_P (templ)))
7238 if (complain & tf_error)
7240 error ("non-template type %qT used as a template", d1);
7242 error ("for template declaration %q+D", in_decl);
7244 return error_mark_node;
7247 complain &= ~tf_user;
7249 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7251 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7252 template arguments */
7258 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7260 /* Consider an example where a template template parameter declared as
7262 template <class T, class U = std::allocator<T> > class TT
7264 The template parameter level of T and U are one level larger than
7265 of TT. To proper process the default argument of U, say when an
7266 instantiation `TT<int>' is seen, we need to build the full
7267 arguments containing {int} as the innermost level. Outer levels,
7268 available when not appearing as default template argument, can be
7269 obtained from the arguments of the enclosing template.
7271 Suppose that TT is later substituted with std::vector. The above
7272 instantiation is `TT<int, std::allocator<T> >' with TT at
7273 level 1, and T at level 2, while the template arguments at level 1
7274 becomes {std::vector} and the inner level 2 is {int}. */
7276 outer = DECL_CONTEXT (templ);
7278 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7279 else if (current_template_parms)
7280 /* This is an argument of the current template, so we haven't set
7281 DECL_CONTEXT yet. */
7282 outer = current_template_args ();
7285 arglist = add_to_template_args (outer, arglist);
7287 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7289 /*require_all_args=*/true,
7290 /*use_default_args=*/true);
7291 if (arglist2 == error_mark_node
7292 || (!uses_template_parms (arglist2)
7293 && check_instantiated_args (templ, arglist2, complain)))
7294 return error_mark_node;
7296 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7301 tree template_type = TREE_TYPE (templ);
7304 tree found = NULL_TREE;
7307 int is_dependent_type;
7308 int use_partial_inst_tmpl = false;
7310 if (template_type == error_mark_node)
7311 /* An error occured while building the template TEMPL, and a
7312 diagnostic has most certainly been emitted for that
7313 already. Let's propagate that error. */
7314 return error_mark_node;
7316 gen_tmpl = most_general_template (templ);
7317 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7318 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7319 arg_depth = TMPL_ARGS_DEPTH (arglist);
7321 if (arg_depth == 1 && parm_depth > 1)
7323 /* We've been given an incomplete set of template arguments.
7326 template <class T> struct S1 {
7327 template <class U> struct S2 {};
7328 template <class U> struct S2<U*> {};
7331 we will be called with an ARGLIST of `U*', but the
7332 TEMPLATE will be `template <class T> template
7333 <class U> struct S1<T>::S2'. We must fill in the missing
7336 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7338 arg_depth = TMPL_ARGS_DEPTH (arglist);
7341 /* Now we should have enough arguments. */
7342 gcc_assert (parm_depth == arg_depth);
7344 /* From here on, we're only interested in the most general
7347 /* Calculate the BOUND_ARGS. These will be the args that are
7348 actually tsubst'd into the definition to create the
7352 /* We have multiple levels of arguments to coerce, at once. */
7354 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7356 tree bound_args = make_tree_vec (parm_depth);
7358 for (i = saved_depth,
7359 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7360 i > 0 && t != NULL_TREE;
7361 --i, t = TREE_CHAIN (t))
7364 if (i == saved_depth)
7365 a = coerce_template_parms (TREE_VALUE (t),
7368 /*require_all_args=*/true,
7369 /*use_default_args=*/true);
7371 /* Outer levels should have already been coerced. */
7372 a = TMPL_ARGS_LEVEL (arglist, i);
7374 /* Don't process further if one of the levels fails. */
7375 if (a == error_mark_node)
7377 /* Restore the ARGLIST to its full size. */
7378 TREE_VEC_LENGTH (arglist) = saved_depth;
7379 return error_mark_node;
7382 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7384 /* We temporarily reduce the length of the ARGLIST so
7385 that coerce_template_parms will see only the arguments
7386 corresponding to the template parameters it is
7388 TREE_VEC_LENGTH (arglist)--;
7391 /* Restore the ARGLIST to its full size. */
7392 TREE_VEC_LENGTH (arglist) = saved_depth;
7394 arglist = bound_args;
7398 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7399 INNERMOST_TEMPLATE_ARGS (arglist),
7402 /*require_all_args=*/true,
7403 /*use_default_args=*/true);
7405 if (arglist == error_mark_node)
7406 /* We were unable to bind the arguments. */
7407 return error_mark_node;
7409 /* In the scope of a template class, explicit references to the
7410 template class refer to the type of the template, not any
7411 instantiation of it. For example, in:
7413 template <class T> class C { void f(C<T>); }
7415 the `C<T>' is just the same as `C'. Outside of the
7416 class, however, such a reference is an instantiation. */
7418 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7419 || currently_open_class (template_type))
7420 /* comp_template_args is expensive, check it last. */
7421 && comp_template_args (TYPE_TI_ARGS (template_type),
7423 return template_type;
7425 /* If we already have this specialization, return it. */
7426 elt.tmpl = gen_tmpl;
7428 hash = hash_specialization (&elt);
7429 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7435 is_dependent_type = uses_template_parms (arglist);
7437 /* If the deduced arguments are invalid, then the binding
7439 if (!is_dependent_type
7440 && check_instantiated_args (gen_tmpl,
7441 INNERMOST_TEMPLATE_ARGS (arglist),
7443 return error_mark_node;
7445 if (!is_dependent_type
7446 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7447 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7448 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7450 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7451 DECL_NAME (gen_tmpl),
7452 /*tag_scope=*/ts_global);
7456 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7459 context = global_namespace;
7461 /* Create the type. */
7462 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7464 if (!is_dependent_type)
7466 set_current_access_from_decl (TYPE_NAME (template_type));
7467 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7468 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7469 arglist, complain, in_decl),
7470 SCOPED_ENUM_P (template_type), NULL);
7474 /* We don't want to call start_enum for this type, since
7475 the values for the enumeration constants may involve
7476 template parameters. And, no one should be interested
7477 in the enumeration constants for such a type. */
7478 t = cxx_make_type (ENUMERAL_TYPE);
7479 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7481 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7482 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7483 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7485 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7487 /* The user referred to a specialization of an alias
7488 template represented by GEN_TMPL.
7490 [temp.alias]/2 says:
7492 When a template-id refers to the specialization of an
7493 alias template, it is equivalent to the associated
7494 type obtained by substitution of its
7495 template-arguments for the template-parameters in the
7496 type-id of the alias template. */
7498 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7499 /* Note that the call above (by indirectly calling
7500 register_specialization in tsubst_decl) registers the
7501 TYPE_DECL representing the specialization of the alias
7502 template. So next time someone substitutes ARGLIST for
7503 the template parms into the alias template (GEN_TMPL),
7504 she'll get that TYPE_DECL back. */
7506 if (t == error_mark_node)
7509 else if (CLASS_TYPE_P (template_type))
7511 t = make_class_type (TREE_CODE (template_type));
7512 CLASSTYPE_DECLARED_CLASS (t)
7513 = CLASSTYPE_DECLARED_CLASS (template_type);
7514 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7515 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7517 /* A local class. Make sure the decl gets registered properly. */
7518 if (context == current_function_decl)
7519 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7521 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7522 /* This instantiation is another name for the primary
7523 template type. Set the TYPE_CANONICAL field
7525 TYPE_CANONICAL (t) = template_type;
7526 else if (any_template_arguments_need_structural_equality_p (arglist))
7527 /* Some of the template arguments require structural
7528 equality testing, so this template class requires
7529 structural equality testing. */
7530 SET_TYPE_STRUCTURAL_EQUALITY (t);
7535 /* If we called start_enum or pushtag above, this information
7536 will already be set up. */
7539 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7541 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7542 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7543 DECL_SOURCE_LOCATION (type_decl)
7544 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7547 type_decl = TYPE_NAME (t);
7549 if (CLASS_TYPE_P (template_type))
7551 TREE_PRIVATE (type_decl)
7552 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7553 TREE_PROTECTED (type_decl)
7554 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7555 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7557 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7558 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7562 /* Let's consider the explicit specialization of a member
7563 of a class template specialization that is implicitely instantiated,
7568 template<class U> struct M {}; //#0
7573 struct S<int>::M<char> //#1
7577 [temp.expl.spec]/4 says this is valid.
7579 In this case, when we write:
7582 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7585 When we encounter #1, we want to store the partial instantiation
7586 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7588 For all cases other than this "explicit specialization of member of a
7589 class template", we just want to store the most general template into
7590 the CLASSTYPE_TI_TEMPLATE of M.
7592 This case of "explicit specialization of member of a class template"
7594 1/ the enclosing class is an instantiation of, and therefore not
7595 the same as, the context of the most general template, and
7596 2/ we aren't looking at the partial instantiation itself, i.e.
7597 the innermost arguments are not the same as the innermost parms of
7598 the most general template.
7600 So it's only when 1/ and 2/ happens that we want to use the partial
7601 instantiation of the member template in lieu of its most general
7604 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7605 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7606 /* the enclosing class must be an instantiation... */
7607 && CLASS_TYPE_P (context)
7608 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7610 tree partial_inst_args;
7611 TREE_VEC_LENGTH (arglist)--;
7612 ++processing_template_decl;
7614 tsubst (INNERMOST_TEMPLATE_ARGS
7615 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7616 arglist, complain, NULL_TREE);
7617 --processing_template_decl;
7618 TREE_VEC_LENGTH (arglist)++;
7619 use_partial_inst_tmpl =
7620 /*...and we must not be looking at the partial instantiation
7622 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7626 if (!use_partial_inst_tmpl)
7627 /* This case is easy; there are no member templates involved. */
7631 /* This is a full instantiation of a member template. Find
7632 the partial instantiation of which this is an instance. */
7634 /* Temporarily reduce by one the number of levels in the ARGLIST
7635 so as to avoid comparing the last set of arguments. */
7636 TREE_VEC_LENGTH (arglist)--;
7637 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7638 TREE_VEC_LENGTH (arglist)++;
7639 /* FOUND is either a proper class type, or an alias
7640 template specialization. In the later case, it's a
7641 TYPE_DECL, resulting from the substituting of arguments
7642 for parameters in the TYPE_DECL of the alias template
7643 done earlier. So be careful while getting the template
7645 found = TREE_CODE (found) == TYPE_DECL
7646 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7647 : CLASSTYPE_TI_TEMPLATE (found);
7650 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7653 slot = htab_find_slot_with_hash (type_specializations,
7654 &elt, hash, INSERT);
7655 entry = ggc_alloc_spec_entry ();
7659 /* Note this use of the partial instantiation so we can check it
7660 later in maybe_process_partial_specialization. */
7661 DECL_TEMPLATE_INSTANTIATIONS (templ)
7662 = tree_cons (arglist, t,
7663 DECL_TEMPLATE_INSTANTIATIONS (templ));
7665 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7666 /* Now that the type has been registered on the instantiations
7667 list, we set up the enumerators. Because the enumeration
7668 constants may involve the enumeration type itself, we make
7669 sure to register the type first, and then create the
7670 constants. That way, doing tsubst_expr for the enumeration
7671 constants won't result in recursive calls here; we'll find
7672 the instantiation and exit above. */
7673 tsubst_enum (template_type, t, arglist);
7675 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7676 /* If the type makes use of template parameters, the
7677 code that generates debugging information will crash. */
7678 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7680 /* Possibly limit visibility based on template args. */
7681 TREE_PUBLIC (type_decl) = 1;
7682 determine_visibility (type_decl);
7688 /* Wrapper for lookup_template_class_1. */
7691 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7692 int entering_scope, tsubst_flags_t complain)
7695 timevar_push (TV_TEMPLATE_INST);
7696 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7697 entering_scope, complain);
7698 timevar_pop (TV_TEMPLATE_INST);
7706 /* True when we should also visit template parameters that occur in
7707 non-deduced contexts. */
7708 bool include_nondeduced_p;
7709 struct pointer_set_t *visited;
7712 /* Called from for_each_template_parm via walk_tree. */
7715 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7718 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7719 tree_fn_t fn = pfd->fn;
7720 void *data = pfd->data;
7723 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7724 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7725 pfd->include_nondeduced_p))
7726 return error_mark_node;
7728 switch (TREE_CODE (t))
7731 if (TYPE_PTRMEMFUNC_P (t))
7737 if (!TYPE_TEMPLATE_INFO (t))
7739 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7740 fn, data, pfd->visited,
7741 pfd->include_nondeduced_p))
7742 return error_mark_node;
7746 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7747 fn, data, pfd->visited,
7748 pfd->include_nondeduced_p)
7749 || for_each_template_parm (TYPE_MAX_VALUE (t),
7750 fn, data, pfd->visited,
7751 pfd->include_nondeduced_p))
7752 return error_mark_node;
7756 /* Since we're not going to walk subtrees, we have to do this
7758 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7759 pfd->visited, pfd->include_nondeduced_p))
7760 return error_mark_node;
7764 /* Check the return type. */
7765 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7766 pfd->include_nondeduced_p))
7767 return error_mark_node;
7769 /* Check the parameter types. Since default arguments are not
7770 instantiated until they are needed, the TYPE_ARG_TYPES may
7771 contain expressions that involve template parameters. But,
7772 no-one should be looking at them yet. And, once they're
7773 instantiated, they don't contain template parameters, so
7774 there's no point in looking at them then, either. */
7778 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7779 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7780 pfd->visited, pfd->include_nondeduced_p))
7781 return error_mark_node;
7783 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7784 want walk_tree walking into them itself. */
7790 case UNDERLYING_TYPE:
7791 if (pfd->include_nondeduced_p
7792 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7794 pfd->include_nondeduced_p))
7795 return error_mark_node;
7800 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7801 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7802 pfd->visited, pfd->include_nondeduced_p))
7803 return error_mark_node;
7808 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7809 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7810 pfd->visited, pfd->include_nondeduced_p))
7811 return error_mark_node;
7812 if (DECL_CONTEXT (t)
7813 && pfd->include_nondeduced_p
7814 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7815 pfd->visited, pfd->include_nondeduced_p))
7816 return error_mark_node;
7819 case BOUND_TEMPLATE_TEMPLATE_PARM:
7820 /* Record template parameters such as `T' inside `TT<T>'. */
7821 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7822 pfd->include_nondeduced_p))
7823 return error_mark_node;
7826 case TEMPLATE_TEMPLATE_PARM:
7827 case TEMPLATE_TYPE_PARM:
7828 case TEMPLATE_PARM_INDEX:
7829 if (fn && (*fn)(t, data))
7830 return error_mark_node;
7832 return error_mark_node;
7836 /* A template template parameter is encountered. */
7837 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7838 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7839 pfd->include_nondeduced_p))
7840 return error_mark_node;
7842 /* Already substituted template template parameter */
7848 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7850 pfd->include_nondeduced_p))
7851 return error_mark_node;
7855 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7856 && pfd->include_nondeduced_p
7857 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7858 (TREE_TYPE (t)), fn, data,
7859 pfd->visited, pfd->include_nondeduced_p))
7860 return error_mark_node;
7865 /* If there's no type, then this thing must be some expression
7866 involving template parameters. */
7867 if (!fn && !TREE_TYPE (t))
7868 return error_mark_node;
7873 case IMPLICIT_CONV_EXPR:
7874 case REINTERPRET_CAST_EXPR:
7875 case CONST_CAST_EXPR:
7876 case STATIC_CAST_EXPR:
7877 case DYNAMIC_CAST_EXPR:
7881 case PSEUDO_DTOR_EXPR:
7883 return error_mark_node;
7890 /* We didn't find any template parameters we liked. */
7894 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7895 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7896 call FN with the parameter and the DATA.
7897 If FN returns nonzero, the iteration is terminated, and
7898 for_each_template_parm returns 1. Otherwise, the iteration
7899 continues. If FN never returns a nonzero value, the value
7900 returned by for_each_template_parm is 0. If FN is NULL, it is
7901 considered to be the function which always returns 1.
7903 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7904 parameters that occur in non-deduced contexts. When false, only
7905 visits those template parameters that can be deduced. */
7908 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7909 struct pointer_set_t *visited,
7910 bool include_nondeduced_p)
7912 struct pair_fn_data pfd;
7918 pfd.include_nondeduced_p = include_nondeduced_p;
7920 /* Walk the tree. (Conceptually, we would like to walk without
7921 duplicates, but for_each_template_parm_r recursively calls
7922 for_each_template_parm, so we would need to reorganize a fair
7923 bit to use walk_tree_without_duplicates, so we keep our own
7926 pfd.visited = visited;
7928 pfd.visited = pointer_set_create ();
7929 result = cp_walk_tree (&t,
7930 for_each_template_parm_r,
7932 pfd.visited) != NULL_TREE;
7937 pointer_set_destroy (pfd.visited);
7944 /* Returns true if T depends on any template parameter. */
7947 uses_template_parms (tree t)
7950 int saved_processing_template_decl;
7952 saved_processing_template_decl = processing_template_decl;
7953 if (!saved_processing_template_decl)
7954 processing_template_decl = 1;
7956 dependent_p = dependent_type_p (t);
7957 else if (TREE_CODE (t) == TREE_VEC)
7958 dependent_p = any_dependent_template_arguments_p (t);
7959 else if (TREE_CODE (t) == TREE_LIST)
7960 dependent_p = (uses_template_parms (TREE_VALUE (t))
7961 || uses_template_parms (TREE_CHAIN (t)));
7962 else if (TREE_CODE (t) == TYPE_DECL)
7963 dependent_p = dependent_type_p (TREE_TYPE (t));
7966 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7967 || TREE_CODE (t) == OVERLOAD
7969 || TREE_CODE (t) == IDENTIFIER_NODE
7970 || TREE_CODE (t) == TRAIT_EXPR
7971 || TREE_CODE (t) == CONSTRUCTOR
7972 || CONSTANT_CLASS_P (t))
7973 dependent_p = (type_dependent_expression_p (t)
7974 || value_dependent_expression_p (t));
7977 gcc_assert (t == error_mark_node);
7978 dependent_p = false;
7981 processing_template_decl = saved_processing_template_decl;
7986 /* Returns true if T depends on any template parameter with level LEVEL. */
7989 uses_template_parms_level (tree t, int level)
7991 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7992 /*include_nondeduced_p=*/true);
7995 /* Returns TRUE iff INST is an instantiation we don't need to do in an
7996 ill-formed translation unit, i.e. a variable or function that isn't
7997 usable in a constant expression. */
8000 neglectable_inst_p (tree d)
8003 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
8004 : decl_maybe_constant_var_p (d)));
8007 /* Returns TRUE iff we should refuse to instantiate DECL because it's
8008 neglectable and instantiated from within an erroneous instantiation. */
8011 limit_bad_template_recursion (tree decl)
8013 struct tinst_level *lev = current_tinst_level;
8014 int errs = errorcount + sorrycount;
8015 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
8018 for (; lev; lev = lev->next)
8019 if (neglectable_inst_p (lev->decl))
8022 return (lev && errs > lev->errors);
8025 static int tinst_depth;
8026 extern int max_tinst_depth;
8027 #ifdef GATHER_STATISTICS
8030 static GTY(()) struct tinst_level *last_error_tinst_level;
8032 /* We're starting to instantiate D; record the template instantiation context
8033 for diagnostics and to restore it later. */
8036 push_tinst_level (tree d)
8038 struct tinst_level *new_level;
8040 if (tinst_depth >= max_tinst_depth)
8042 last_error_tinst_level = current_tinst_level;
8043 if (TREE_CODE (d) == TREE_LIST)
8044 error ("template instantiation depth exceeds maximum of %d (use "
8045 "-ftemplate-depth= to increase the maximum) substituting %qS",
8046 max_tinst_depth, d);
8048 error ("template instantiation depth exceeds maximum of %d (use "
8049 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8050 max_tinst_depth, d);
8052 print_instantiation_context ();
8057 /* If the current instantiation caused problems, don't let it instantiate
8058 anything else. Do allow deduction substitution and decls usable in
8059 constant expressions. */
8060 if (limit_bad_template_recursion (d))
8063 new_level = ggc_alloc_tinst_level ();
8064 new_level->decl = d;
8065 new_level->locus = input_location;
8066 new_level->errors = errorcount+sorrycount;
8067 new_level->in_system_header_p = in_system_header;
8068 new_level->next = current_tinst_level;
8069 current_tinst_level = new_level;
8072 #ifdef GATHER_STATISTICS
8073 if (tinst_depth > depth_reached)
8074 depth_reached = tinst_depth;
8080 /* We're done instantiating this template; return to the instantiation
8084 pop_tinst_level (void)
8086 /* Restore the filename and line number stashed away when we started
8087 this instantiation. */
8088 input_location = current_tinst_level->locus;
8089 current_tinst_level = current_tinst_level->next;
8093 /* We're instantiating a deferred template; restore the template
8094 instantiation context in which the instantiation was requested, which
8095 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8098 reopen_tinst_level (struct tinst_level *level)
8100 struct tinst_level *t;
8103 for (t = level; t; t = t->next)
8106 current_tinst_level = level;
8108 if (current_tinst_level)
8109 current_tinst_level->errors = errorcount+sorrycount;
8113 /* Returns the TINST_LEVEL which gives the original instantiation
8116 struct tinst_level *
8117 outermost_tinst_level (void)
8119 struct tinst_level *level = current_tinst_level;
8122 level = level->next;
8126 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8129 parameter_of_template_p (tree parm, tree templ)
8134 if (!parm || !templ)
8137 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8138 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8140 parms = DECL_TEMPLATE_PARMS (templ);
8141 parms = INNERMOST_TEMPLATE_PARMS (parms);
8143 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8145 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8147 || (DECL_INITIAL (parm)
8148 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8155 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8156 vector of template arguments, as for tsubst.
8158 Returns an appropriate tsubst'd friend declaration. */
8161 tsubst_friend_function (tree decl, tree args)
8165 if (TREE_CODE (decl) == FUNCTION_DECL
8166 && DECL_TEMPLATE_INSTANTIATION (decl)
8167 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8168 /* This was a friend declared with an explicit template
8169 argument list, e.g.:
8173 to indicate that f was a template instantiation, not a new
8174 function declaration. Now, we have to figure out what
8175 instantiation of what template. */
8177 tree template_id, arglist, fns;
8180 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8182 /* Friend functions are looked up in the containing namespace scope.
8183 We must enter that scope, to avoid finding member functions of the
8184 current class with same name. */
8185 push_nested_namespace (ns);
8186 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8187 tf_warning_or_error, NULL_TREE,
8188 /*integral_constant_expression_p=*/false);
8189 pop_nested_namespace (ns);
8190 arglist = tsubst (DECL_TI_ARGS (decl), args,
8191 tf_warning_or_error, NULL_TREE);
8192 template_id = lookup_template_function (fns, arglist);
8194 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8195 tmpl = determine_specialization (template_id, new_friend,
8197 /*need_member_template=*/0,
8198 TREE_VEC_LENGTH (args),
8200 return instantiate_template (tmpl, new_args, tf_error);
8203 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8205 /* The NEW_FRIEND will look like an instantiation, to the
8206 compiler, but is not an instantiation from the point of view of
8207 the language. For example, we might have had:
8209 template <class T> struct S {
8210 template <class U> friend void f(T, U);
8213 Then, in S<int>, template <class U> void f(int, U) is not an
8214 instantiation of anything. */
8215 if (new_friend == error_mark_node)
8216 return error_mark_node;
8218 DECL_USE_TEMPLATE (new_friend) = 0;
8219 if (TREE_CODE (decl) == TEMPLATE_DECL)
8221 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8222 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8223 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8226 /* The mangled name for the NEW_FRIEND is incorrect. The function
8227 is not a template instantiation and should not be mangled like
8228 one. Therefore, we forget the mangling here; we'll recompute it
8229 later if we need it. */
8230 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8232 SET_DECL_RTL (new_friend, NULL);
8233 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8236 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8239 tree new_friend_template_info;
8240 tree new_friend_result_template_info;
8242 int new_friend_is_defn;
8244 /* We must save some information from NEW_FRIEND before calling
8245 duplicate decls since that function will free NEW_FRIEND if
8247 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8248 new_friend_is_defn =
8249 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8250 (template_for_substitution (new_friend)))
8252 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8254 /* This declaration is a `primary' template. */
8255 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8257 new_friend_result_template_info
8258 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8261 new_friend_result_template_info = NULL_TREE;
8263 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8264 if (new_friend_is_defn)
8265 DECL_INITIAL (new_friend) = error_mark_node;
8267 /* Inside pushdecl_namespace_level, we will push into the
8268 current namespace. However, the friend function should go
8269 into the namespace of the template. */
8270 ns = decl_namespace_context (new_friend);
8271 push_nested_namespace (ns);
8272 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8273 pop_nested_namespace (ns);
8275 if (old_decl == error_mark_node)
8276 return error_mark_node;
8278 if (old_decl != new_friend)
8280 /* This new friend declaration matched an existing
8281 declaration. For example, given:
8283 template <class T> void f(T);
8284 template <class U> class C {
8285 template <class T> friend void f(T) {}
8288 the friend declaration actually provides the definition
8289 of `f', once C has been instantiated for some type. So,
8290 old_decl will be the out-of-class template declaration,
8291 while new_friend is the in-class definition.
8293 But, if `f' was called before this point, the
8294 instantiation of `f' will have DECL_TI_ARGS corresponding
8295 to `T' but not to `U', references to which might appear
8296 in the definition of `f'. Previously, the most general
8297 template for an instantiation of `f' was the out-of-class
8298 version; now it is the in-class version. Therefore, we
8299 run through all specialization of `f', adding to their
8300 DECL_TI_ARGS appropriately. In particular, they need a
8301 new set of outer arguments, corresponding to the
8302 arguments for this class instantiation.
8304 The same situation can arise with something like this:
8307 template <class T> class C {
8311 when `C<int>' is instantiated. Now, `f(int)' is defined
8314 if (!new_friend_is_defn)
8315 /* On the other hand, if the in-class declaration does
8316 *not* provide a definition, then we don't want to alter
8317 existing definitions. We can just leave everything
8322 tree new_template = TI_TEMPLATE (new_friend_template_info);
8323 tree new_args = TI_ARGS (new_friend_template_info);
8325 /* Overwrite whatever template info was there before, if
8326 any, with the new template information pertaining to
8328 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8330 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8332 /* We should have called reregister_specialization in
8334 gcc_assert (retrieve_specialization (new_template,
8338 /* Instantiate it if the global has already been used. */
8339 if (DECL_ODR_USED (old_decl))
8340 instantiate_decl (old_decl, /*defer_ok=*/true,
8341 /*expl_inst_class_mem_p=*/false);
8347 /* Indicate that the old function template is a partial
8349 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8350 = new_friend_result_template_info;
8352 gcc_assert (new_template
8353 == most_general_template (new_template));
8354 gcc_assert (new_template != old_decl);
8356 /* Reassign any specializations already in the hash table
8357 to the new more general template, and add the
8358 additional template args. */
8359 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8363 tree spec = TREE_VALUE (t);
8366 elt.tmpl = old_decl;
8367 elt.args = DECL_TI_ARGS (spec);
8368 elt.spec = NULL_TREE;
8370 htab_remove_elt (decl_specializations, &elt);
8373 = add_outermost_template_args (new_args,
8374 DECL_TI_ARGS (spec));
8376 register_specialization
8377 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8380 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8384 /* The information from NEW_FRIEND has been merged into OLD_DECL
8385 by duplicate_decls. */
8386 new_friend = old_decl;
8391 tree context = DECL_CONTEXT (new_friend);
8395 template <class T> class C {
8396 template <class U> friend void C1<U>::f (); // case 1
8397 friend void C2<T>::f (); // case 2
8399 we only need to make sure CONTEXT is a complete type for
8400 case 2. To distinguish between the two cases, we note that
8401 CONTEXT of case 1 remains dependent type after tsubst while
8402 this isn't true for case 2. */
8403 ++processing_template_decl;
8404 dependent_p = dependent_type_p (context);
8405 --processing_template_decl;
8408 && !complete_type_or_else (context, NULL_TREE))
8409 return error_mark_node;
8411 if (COMPLETE_TYPE_P (context))
8413 /* Check to see that the declaration is really present, and,
8414 possibly obtain an improved declaration. */
8415 tree fn = check_classfn (context,
8416 new_friend, NULL_TREE);
8426 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8427 template arguments, as for tsubst.
8429 Returns an appropriate tsubst'd friend type or error_mark_node on
8433 tsubst_friend_class (tree friend_tmpl, tree args)
8439 context = CP_DECL_CONTEXT (friend_tmpl);
8441 if (context != global_namespace)
8443 if (TREE_CODE (context) == NAMESPACE_DECL)
8444 push_nested_namespace (context);
8446 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8449 /* Look for a class template declaration. We look for hidden names
8450 because two friend declarations of the same template are the
8451 same. For example, in:
8454 template <typename> friend class F;
8456 template <typename> struct B {
8457 template <typename> friend class F;
8460 both F templates are the same. */
8461 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8462 /*block_p=*/true, 0,
8463 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8465 /* But, if we don't find one, it might be because we're in a
8466 situation like this:
8474 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8475 for `S<int>', not the TEMPLATE_DECL. */
8476 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8478 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8479 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8482 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8484 /* The friend template has already been declared. Just
8485 check to see that the declarations match, and install any new
8486 default parameters. We must tsubst the default parameters,
8487 of course. We only need the innermost template parameters
8488 because that is all that redeclare_class_template will look
8490 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8491 > TMPL_ARGS_DEPTH (args))
8494 location_t saved_input_location;
8495 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8496 args, tf_warning_or_error);
8498 saved_input_location = input_location;
8499 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8500 redeclare_class_template (TREE_TYPE (tmpl), parms);
8501 input_location = saved_input_location;
8505 friend_type = TREE_TYPE (tmpl);
8509 /* The friend template has not already been declared. In this
8510 case, the instantiation of the template class will cause the
8511 injection of this template into the global scope. */
8512 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8513 if (tmpl == error_mark_node)
8514 return error_mark_node;
8516 /* The new TMPL is not an instantiation of anything, so we
8517 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8518 the new type because that is supposed to be the corresponding
8519 template decl, i.e., TMPL. */
8520 DECL_USE_TEMPLATE (tmpl) = 0;
8521 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8522 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8523 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8524 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8526 /* Inject this template into the global scope. */
8527 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8530 if (context != global_namespace)
8532 if (TREE_CODE (context) == NAMESPACE_DECL)
8533 pop_nested_namespace (context);
8535 pop_nested_class ();
8541 /* Returns zero if TYPE cannot be completed later due to circularity.
8542 Otherwise returns one. */
8545 can_complete_type_without_circularity (tree type)
8547 if (type == NULL_TREE || type == error_mark_node)
8549 else if (COMPLETE_TYPE_P (type))
8551 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8552 return can_complete_type_without_circularity (TREE_TYPE (type));
8553 else if (CLASS_TYPE_P (type)
8554 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8560 /* Apply any attributes which had to be deferred until instantiation
8561 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8562 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8565 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8566 tree args, tsubst_flags_t complain, tree in_decl)
8568 tree last_dep = NULL_TREE;
8572 for (t = attributes; t; t = TREE_CHAIN (t))
8573 if (ATTR_IS_DEPENDENT (t))
8576 attributes = copy_list (attributes);
8580 if (DECL_P (*decl_p))
8582 if (TREE_TYPE (*decl_p) == error_mark_node)
8584 p = &DECL_ATTRIBUTES (*decl_p);
8587 p = &TYPE_ATTRIBUTES (*decl_p);
8591 tree late_attrs = NULL_TREE;
8592 tree *q = &late_attrs;
8594 for (*p = attributes; *p; )
8597 if (ATTR_IS_DEPENDENT (t))
8599 *p = TREE_CHAIN (t);
8600 TREE_CHAIN (t) = NULL_TREE;
8601 /* If the first attribute argument is an identifier, don't
8602 pass it through tsubst. Attributes like mode, format,
8603 cleanup and several target specific attributes expect it
8606 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8607 && TREE_VALUE (TREE_VALUE (t))
8608 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8609 == IDENTIFIER_NODE))
8612 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8614 /*integral_constant_expression_p=*/false);
8615 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8617 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8622 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8623 /*integral_constant_expression_p=*/false);
8625 q = &TREE_CHAIN (t);
8628 p = &TREE_CHAIN (t);
8631 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8635 /* Perform (or defer) access check for typedefs that were referenced
8636 from within the template TMPL code.
8637 This is a subroutine of instantiate_template and instantiate_class_template.
8638 TMPL is the template to consider and TARGS is the list of arguments of
8642 perform_typedefs_access_check (tree tmpl, tree targs)
8644 location_t saved_location;
8646 qualified_typedef_usage_t *iter;
8649 || (!CLASS_TYPE_P (tmpl)
8650 && TREE_CODE (tmpl) != FUNCTION_DECL))
8653 saved_location = input_location;
8654 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8655 get_types_needing_access_check (tmpl),
8658 tree type_decl = iter->typedef_decl;
8659 tree type_scope = iter->context;
8661 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8664 if (uses_template_parms (type_decl))
8665 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8666 if (uses_template_parms (type_scope))
8667 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8669 /* Make access check error messages point to the location
8670 of the use of the typedef. */
8671 input_location = iter->locus;
8672 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8673 type_decl, type_decl);
8675 input_location = saved_location;
8679 instantiate_class_template_1 (tree type)
8681 tree templ, args, pattern, t, member;
8685 unsigned int saved_maximum_field_alignment;
8687 if (type == error_mark_node)
8688 return error_mark_node;
8690 if (COMPLETE_OR_OPEN_TYPE_P (type)
8691 || uses_template_parms (type))
8694 /* Figure out which template is being instantiated. */
8695 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8696 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8698 /* Determine what specialization of the original template to
8700 t = most_specialized_class (type, templ, tf_warning_or_error);
8701 if (t == error_mark_node)
8703 TYPE_BEING_DEFINED (type) = 1;
8704 return error_mark_node;
8708 /* This TYPE is actually an instantiation of a partial
8709 specialization. We replace the innermost set of ARGS with
8710 the arguments appropriate for substitution. For example,
8713 template <class T> struct S {};
8714 template <class T> struct S<T*> {};
8716 and supposing that we are instantiating S<int*>, ARGS will
8717 presently be {int*} -- but we need {int}. */
8718 pattern = TREE_TYPE (t);
8719 args = TREE_PURPOSE (t);
8723 pattern = TREE_TYPE (templ);
8724 args = CLASSTYPE_TI_ARGS (type);
8727 /* If the template we're instantiating is incomplete, then clearly
8728 there's nothing we can do. */
8729 if (!COMPLETE_TYPE_P (pattern))
8732 /* If we've recursively instantiated too many templates, stop. */
8733 if (! push_tinst_level (type))
8736 /* Now we're really doing the instantiation. Mark the type as in
8737 the process of being defined. */
8738 TYPE_BEING_DEFINED (type) = 1;
8740 /* We may be in the middle of deferred access check. Disable
8742 push_deferring_access_checks (dk_no_deferred);
8744 push_to_top_level ();
8745 /* Use #pragma pack from the template context. */
8746 saved_maximum_field_alignment = maximum_field_alignment;
8747 maximum_field_alignment = TYPE_PRECISION (pattern);
8749 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8751 /* Set the input location to the most specialized template definition.
8752 This is needed if tsubsting causes an error. */
8753 typedecl = TYPE_MAIN_DECL (pattern);
8754 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8755 DECL_SOURCE_LOCATION (typedecl);
8757 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8758 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8759 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8760 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8761 if (ANON_AGGR_TYPE_P (pattern))
8762 SET_ANON_AGGR_TYPE_P (type);
8763 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8765 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8766 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8767 /* Adjust visibility for template arguments. */
8768 determine_visibility (TYPE_MAIN_DECL (type));
8770 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8772 pbinfo = TYPE_BINFO (pattern);
8774 /* We should never instantiate a nested class before its enclosing
8775 class; we need to look up the nested class by name before we can
8776 instantiate it, and that lookup should instantiate the enclosing
8778 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8779 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8781 base_list = NULL_TREE;
8782 if (BINFO_N_BASE_BINFOS (pbinfo))
8788 /* We must enter the scope containing the type, as that is where
8789 the accessibility of types named in dependent bases are
8791 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8793 /* Substitute into each of the bases to determine the actual
8795 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8798 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8799 tree expanded_bases = NULL_TREE;
8802 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8805 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8806 args, tf_error, NULL_TREE);
8807 if (expanded_bases == error_mark_node)
8810 len = TREE_VEC_LENGTH (expanded_bases);
8813 for (idx = 0; idx < len; idx++)
8816 /* Extract the already-expanded base class. */
8817 base = TREE_VEC_ELT (expanded_bases, idx);
8819 /* Substitute to figure out the base class. */
8820 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8823 if (base == error_mark_node)
8826 base_list = tree_cons (access, base, base_list);
8827 if (BINFO_VIRTUAL_P (pbase_binfo))
8828 TREE_TYPE (base_list) = integer_type_node;
8832 /* The list is now in reverse order; correct that. */
8833 base_list = nreverse (base_list);
8836 pop_scope (pushed_scope);
8838 /* Now call xref_basetypes to set up all the base-class
8840 xref_basetypes (type, base_list);
8842 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8843 (int) ATTR_FLAG_TYPE_IN_PLACE,
8844 args, tf_error, NULL_TREE);
8845 fixup_attribute_variants (type);
8847 /* Now that our base classes are set up, enter the scope of the
8848 class, so that name lookups into base classes, etc. will work
8849 correctly. This is precisely analogous to what we do in
8850 begin_class_definition when defining an ordinary non-template
8851 class, except we also need to push the enclosing classes. */
8852 push_nested_class (type);
8854 /* Now members are processed in the order of declaration. */
8855 for (member = CLASSTYPE_DECL_LIST (pattern);
8856 member; member = TREE_CHAIN (member))
8858 tree t = TREE_VALUE (member);
8860 if (TREE_PURPOSE (member))
8864 /* Build new CLASSTYPE_NESTED_UTDS. */
8867 bool class_template_p;
8869 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8870 && TYPE_LANG_SPECIFIC (t)
8871 && CLASSTYPE_IS_TEMPLATE (t));
8872 /* If the member is a class template, then -- even after
8873 substitution -- there may be dependent types in the
8874 template argument list for the class. We increment
8875 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8876 that function will assume that no types are dependent
8877 when outside of a template. */
8878 if (class_template_p)
8879 ++processing_template_decl;
8880 newtag = tsubst (t, args, tf_error, NULL_TREE);
8881 if (class_template_p)
8882 --processing_template_decl;
8883 if (newtag == error_mark_node)
8886 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8888 tree name = TYPE_IDENTIFIER (t);
8890 if (class_template_p)
8891 /* Unfortunately, lookup_template_class sets
8892 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8893 instantiation (i.e., for the type of a member
8894 template class nested within a template class.)
8895 This behavior is required for
8896 maybe_process_partial_specialization to work
8897 correctly, but is not accurate in this case;
8898 the TAG is not an instantiation of anything.
8899 (The corresponding TEMPLATE_DECL is an
8900 instantiation, but the TYPE is not.) */
8901 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8903 /* Now, we call pushtag to put this NEWTAG into the scope of
8904 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8905 pushtag calling push_template_decl. We don't have to do
8906 this for enums because it will already have been done in
8909 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8910 pushtag (name, newtag, /*tag_scope=*/ts_current);
8913 else if (TREE_CODE (t) == FUNCTION_DECL
8914 || DECL_FUNCTION_TEMPLATE_P (t))
8916 /* Build new TYPE_METHODS. */
8919 if (TREE_CODE (t) == TEMPLATE_DECL)
8920 ++processing_template_decl;
8921 r = tsubst (t, args, tf_error, NULL_TREE);
8922 if (TREE_CODE (t) == TEMPLATE_DECL)
8923 --processing_template_decl;
8924 set_current_access_from_decl (r);
8925 finish_member_declaration (r);
8926 /* Instantiate members marked with attribute used. */
8927 if (r != error_mark_node && DECL_PRESERVE_P (r))
8932 /* Build new TYPE_FIELDS. */
8933 if (TREE_CODE (t) == STATIC_ASSERT)
8936 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8937 tf_warning_or_error, NULL_TREE,
8938 /*integral_constant_expression_p=*/true);
8939 finish_static_assert (condition,
8940 STATIC_ASSERT_MESSAGE (t),
8941 STATIC_ASSERT_SOURCE_LOCATION (t),
8944 else if (TREE_CODE (t) != CONST_DECL)
8948 /* The file and line for this declaration, to
8949 assist in error message reporting. Since we
8950 called push_tinst_level above, we don't need to
8952 input_location = DECL_SOURCE_LOCATION (t);
8954 if (TREE_CODE (t) == TEMPLATE_DECL)
8955 ++processing_template_decl;
8956 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8957 if (TREE_CODE (t) == TEMPLATE_DECL)
8958 --processing_template_decl;
8959 if (TREE_CODE (r) == VAR_DECL)
8963 [t]he initialization (and any associated
8964 side-effects) of a static data member does
8965 not occur unless the static data member is
8966 itself used in a way that requires the
8967 definition of the static data member to
8970 Therefore, we do not substitute into the
8971 initialized for the static data member here. */
8972 finish_static_data_member_decl
8975 /*init_const_expr_p=*/false,
8976 /*asmspec_tree=*/NULL_TREE,
8978 /* Instantiate members marked with attribute used. */
8979 if (r != error_mark_node && DECL_PRESERVE_P (r))
8982 else if (TREE_CODE (r) == FIELD_DECL)
8984 /* Determine whether R has a valid type and can be
8985 completed later. If R is invalid, then it is
8986 replaced by error_mark_node so that it will not be
8987 added to TYPE_FIELDS. */
8988 tree rtype = TREE_TYPE (r);
8989 if (can_complete_type_without_circularity (rtype))
8990 complete_type (rtype);
8992 if (!COMPLETE_TYPE_P (rtype))
8994 cxx_incomplete_type_error (r, rtype);
8995 r = error_mark_node;
8999 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
9000 such a thing will already have been added to the field
9001 list by tsubst_enum in finish_member_declaration in the
9002 CLASSTYPE_NESTED_UTDS case above. */
9003 if (!(TREE_CODE (r) == TYPE_DECL
9004 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
9005 && DECL_ARTIFICIAL (r)))
9007 set_current_access_from_decl (r);
9008 finish_member_declaration (r);
9015 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
9017 /* Build new CLASSTYPE_FRIEND_CLASSES. */
9019 tree friend_type = t;
9020 bool adjust_processing_template_decl = false;
9022 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9024 /* template <class T> friend class C; */
9025 friend_type = tsubst_friend_class (friend_type, args);
9026 adjust_processing_template_decl = true;
9028 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9030 /* template <class T> friend class C::D; */
9031 friend_type = tsubst (friend_type, args,
9032 tf_warning_or_error, NULL_TREE);
9033 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9034 friend_type = TREE_TYPE (friend_type);
9035 adjust_processing_template_decl = true;
9037 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9038 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9040 /* This could be either
9044 when dependent_type_p is false or
9046 template <class U> friend class T::C;
9049 friend_type = tsubst (friend_type, args,
9050 tf_warning_or_error, NULL_TREE);
9051 /* Bump processing_template_decl for correct
9052 dependent_type_p calculation. */
9053 ++processing_template_decl;
9054 if (dependent_type_p (friend_type))
9055 adjust_processing_template_decl = true;
9056 --processing_template_decl;
9058 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9059 && hidden_name_p (TYPE_NAME (friend_type)))
9063 where C hasn't been declared yet. Let's lookup name
9064 from namespace scope directly, bypassing any name that
9065 come from dependent base class. */
9066 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9068 /* The call to xref_tag_from_type does injection for friend
9070 push_nested_namespace (ns);
9072 xref_tag_from_type (friend_type, NULL_TREE,
9073 /*tag_scope=*/ts_current);
9074 pop_nested_namespace (ns);
9076 else if (uses_template_parms (friend_type))
9077 /* friend class C<T>; */
9078 friend_type = tsubst (friend_type, args,
9079 tf_warning_or_error, NULL_TREE);
9084 where C is already declared or
9086 friend class C<int>;
9088 We don't have to do anything in these cases. */
9090 if (adjust_processing_template_decl)
9091 /* Trick make_friend_class into realizing that the friend
9092 we're adding is a template, not an ordinary class. It's
9093 important that we use make_friend_class since it will
9094 perform some error-checking and output cross-reference
9096 ++processing_template_decl;
9098 if (friend_type != error_mark_node)
9099 make_friend_class (type, friend_type, /*complain=*/false);
9101 if (adjust_processing_template_decl)
9102 --processing_template_decl;
9106 /* Build new DECL_FRIENDLIST. */
9109 /* The file and line for this declaration, to
9110 assist in error message reporting. Since we
9111 called push_tinst_level above, we don't need to
9113 input_location = DECL_SOURCE_LOCATION (t);
9115 if (TREE_CODE (t) == TEMPLATE_DECL)
9117 ++processing_template_decl;
9118 push_deferring_access_checks (dk_no_check);
9121 r = tsubst_friend_function (t, args);
9122 add_friend (type, r, /*complain=*/false);
9123 if (TREE_CODE (t) == TEMPLATE_DECL)
9125 pop_deferring_access_checks ();
9126 --processing_template_decl;
9132 if (CLASSTYPE_LAMBDA_EXPR (type))
9134 tree decl = lambda_function (type);
9137 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9138 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9140 apply_lambda_return_type (lambda, void_type_node);
9141 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9143 instantiate_decl (decl, false, false);
9144 maybe_add_lambda_conv_op (type);
9147 gcc_assert (errorcount);
9150 /* Set the file and line number information to whatever is given for
9151 the class itself. This puts error messages involving generated
9152 implicit functions at a predictable point, and the same point
9153 that would be used for non-template classes. */
9154 input_location = DECL_SOURCE_LOCATION (typedecl);
9156 unreverse_member_declarations (type);
9157 finish_struct_1 (type);
9158 TYPE_BEING_DEFINED (type) = 0;
9160 /* We don't instantiate default arguments for member functions. 14.7.1:
9162 The implicit instantiation of a class template specialization causes
9163 the implicit instantiation of the declarations, but not of the
9164 definitions or default arguments, of the class member functions,
9165 member classes, static data members and member templates.... */
9167 /* Some typedefs referenced from within the template code need to be access
9168 checked at template instantiation time, i.e now. These types were
9169 added to the template at parsing time. Let's get those and perform
9170 the access checks then. */
9171 perform_typedefs_access_check (pattern, args);
9172 perform_deferred_access_checks ();
9173 pop_nested_class ();
9174 maximum_field_alignment = saved_maximum_field_alignment;
9175 pop_from_top_level ();
9176 pop_deferring_access_checks ();
9179 /* The vtable for a template class can be emitted in any translation
9180 unit in which the class is instantiated. When there is no key
9181 method, however, finish_struct_1 will already have added TYPE to
9182 the keyed_classes list. */
9183 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9184 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9189 /* Wrapper for instantiate_class_template_1. */
9192 instantiate_class_template (tree type)
9195 timevar_push (TV_TEMPLATE_INST);
9196 ret = instantiate_class_template_1 (type);
9197 timevar_pop (TV_TEMPLATE_INST);
9202 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9208 else if (TYPE_P (t))
9209 r = tsubst (t, args, complain, in_decl);
9212 if (!(complain & tf_warning))
9213 ++c_inhibit_evaluation_warnings;
9214 r = tsubst_expr (t, args, complain, in_decl,
9215 /*integral_constant_expression_p=*/true);
9216 if (!(complain & tf_warning))
9217 --c_inhibit_evaluation_warnings;
9218 /* Preserve the raw-reference nature of T. */
9219 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9220 && REFERENCE_REF_P (r))
9221 r = TREE_OPERAND (r, 0);
9226 /* Given a function parameter pack TMPL_PARM and some function parameters
9227 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9228 and set *SPEC_P to point at the next point in the list. */
9231 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9233 /* Collect all of the extra "packed" parameters into an
9237 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9238 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9239 tree spec_parm = *spec_p;
9242 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9244 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9247 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9248 parmvec = make_tree_vec (len);
9249 parmtypevec = make_tree_vec (len);
9250 spec_parm = *spec_p;
9251 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9253 TREE_VEC_ELT (parmvec, i) = spec_parm;
9254 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9257 /* Build the argument packs. */
9258 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9259 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9260 TREE_TYPE (argpack) = argtypepack;
9261 *spec_p = spec_parm;
9266 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9267 NONTYPE_ARGUMENT_PACK. */
9270 make_fnparm_pack (tree spec_parm)
9272 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9275 /* Substitute ARGS into T, which is an pack expansion
9276 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9277 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9278 (if only a partial substitution could be performed) or
9279 ERROR_MARK_NODE if there was an error. */
9281 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9285 tree pack, packs = NULL_TREE;
9286 bool unsubstituted_packs = false;
9287 bool real_packs = false;
9288 int missing_level = 0;
9291 htab_t saved_local_specializations = NULL;
9294 gcc_assert (PACK_EXPANSION_P (t));
9295 pattern = PACK_EXPANSION_PATTERN (t);
9297 /* Add in any args remembered from an earlier partial instantiation. */
9298 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9300 levels = TMPL_ARGS_DEPTH (args);
9302 /* Determine the argument packs that will instantiate the parameter
9303 packs used in the expansion expression. While we're at it,
9304 compute the number of arguments to be expanded and make sure it
9306 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9307 pack = TREE_CHAIN (pack))
9309 tree parm_pack = TREE_VALUE (pack);
9310 tree arg_pack = NULL_TREE;
9311 tree orig_arg = NULL_TREE;
9314 if (TREE_CODE (parm_pack) == BASES)
9316 if (BASES_DIRECT (parm_pack))
9317 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9318 args, complain, in_decl, false));
9320 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9321 args, complain, in_decl, false));
9323 if (TREE_CODE (parm_pack) == PARM_DECL)
9325 if (!cp_unevaluated_operand)
9326 arg_pack = retrieve_local_specialization (parm_pack);
9329 /* We can't rely on local_specializations for a parameter
9330 name used later in a function declaration (such as in a
9331 late-specified return type). Even if it exists, it might
9332 have the wrong value for a recursive call. Just make a
9333 dummy decl, since it's only used for its type. */
9334 arg_pack = tsubst_decl (parm_pack, args, complain);
9335 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9336 /* Partial instantiation of the parm_pack, we can't build
9337 up an argument pack yet. */
9338 arg_pack = NULL_TREE;
9340 arg_pack = make_fnparm_pack (arg_pack);
9346 template_parm_level_and_index (parm_pack, &level, &idx);
9348 if (level <= levels)
9349 arg_pack = TMPL_ARG (args, level, idx);
9352 orig_arg = arg_pack;
9353 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9354 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9356 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9357 /* This can only happen if we forget to expand an argument
9358 pack somewhere else. Just return an error, silently. */
9360 result = make_tree_vec (1);
9361 TREE_VEC_ELT (result, 0) = error_mark_node;
9365 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9366 /* The argument pack that the parameter maps to is just an
9367 expansion of the parameter itself, such as one would find
9368 in the implicit typedef of a class inside the class itself.
9369 Consider this parameter "unsubstituted", so that we will
9370 maintain the outer pack expansion. */
9371 arg_pack = NULL_TREE;
9376 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9378 /* Don't bother trying to do a partial substitution with
9379 incomplete packs; we'll try again after deduction. */
9380 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9385 else if (len != my_len)
9387 if (!(complain & tf_error))
9388 /* Fail quietly. */;
9389 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9390 error ("mismatched argument pack lengths while expanding "
9394 error ("mismatched argument pack lengths while expanding "
9397 return error_mark_node;
9400 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9401 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9403 /* This isn't a real argument pack yet. */;
9407 /* Keep track of the parameter packs and their corresponding
9409 packs = tree_cons (parm_pack, arg_pack, packs);
9410 TREE_TYPE (packs) = orig_arg;
9414 /* We can't substitute for this parameter pack. We use a flag as
9415 well as the missing_level counter because function parameter
9416 packs don't have a level. */
9417 unsubstituted_packs = true;
9418 if (!missing_level || missing_level > level)
9419 missing_level = level;
9423 /* We cannot expand this expansion expression, because we don't have
9424 all of the argument packs we need. */
9425 if (unsubstituted_packs)
9429 /* We got some full packs, but we can't substitute them in until we
9430 have values for all the packs. So remember these until then. */
9433 t = make_pack_expansion (pattern);
9435 /* The call to add_to_template_args above assumes no overlap
9436 between saved args and new args, so prune away any fake
9437 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9438 if (missing_level && levels >= missing_level)
9440 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9441 && missing_level > 1);
9442 TREE_VEC_LENGTH (args) = missing_level - 1;
9443 save_args = copy_node (args);
9444 TREE_VEC_LENGTH (args) = levels;
9449 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9453 /* There were no real arguments, we're just replacing a parameter
9454 pack with another version of itself. Substitute into the
9455 pattern and return a PACK_EXPANSION_*. The caller will need to
9457 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9458 t = tsubst_expr (pattern, args, complain, in_decl,
9459 /*integral_constant_expression_p=*/false);
9461 t = tsubst (pattern, args, complain, in_decl);
9462 t = make_pack_expansion (t);
9467 /* We could not find any argument packs that work. */
9469 return error_mark_node;
9471 if (cp_unevaluated_operand)
9473 /* We're in a late-specified return type, so create our own local
9474 specializations table; the current table is either NULL or (in the
9475 case of recursive unification) might have bindings that we don't
9476 want to use or alter. */
9477 saved_local_specializations = local_specializations;
9478 local_specializations = htab_create (37,
9479 hash_local_specialization,
9480 eq_local_specializations,
9484 /* For each argument in each argument pack, substitute into the
9486 result = make_tree_vec (len);
9487 for (i = 0; i < len; ++i)
9489 /* For parameter pack, change the substitution of the parameter
9490 pack to the ith argument in its argument pack, then expand
9492 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9494 tree parm = TREE_PURPOSE (pack);
9497 /* Select the Ith argument from the pack. */
9498 if (TREE_CODE (parm) == PARM_DECL)
9502 arg = make_node (ARGUMENT_PACK_SELECT);
9503 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9505 register_local_specialization (arg, parm);
9508 arg = retrieve_local_specialization (parm);
9513 template_parm_level_and_index (parm, &level, &idx);
9517 arg = make_node (ARGUMENT_PACK_SELECT);
9518 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9519 /* Update the corresponding argument. */
9520 TMPL_ARG (args, level, idx) = arg;
9523 /* Re-use the ARGUMENT_PACK_SELECT. */
9524 arg = TMPL_ARG (args, level, idx);
9526 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9529 /* Substitute into the PATTERN with the altered arguments. */
9530 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9531 TREE_VEC_ELT (result, i) =
9532 tsubst_expr (pattern, args, complain, in_decl,
9533 /*integral_constant_expression_p=*/false);
9535 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9537 if (TREE_VEC_ELT (result, i) == error_mark_node)
9539 result = error_mark_node;
9544 /* Update ARGS to restore the substitution from parameter packs to
9545 their argument packs. */
9546 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9548 tree parm = TREE_PURPOSE (pack);
9550 if (TREE_CODE (parm) == PARM_DECL)
9551 register_local_specialization (TREE_TYPE (pack), parm);
9555 template_parm_level_and_index (parm, &level, &idx);
9557 /* Update the corresponding argument. */
9558 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9559 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9562 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9566 if (saved_local_specializations)
9568 htab_delete (local_specializations);
9569 local_specializations = saved_local_specializations;
9575 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9576 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9577 parameter packs; all parms generated from a function parameter pack will
9578 have the same DECL_PARM_INDEX. */
9581 get_pattern_parm (tree parm, tree tmpl)
9583 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9586 if (DECL_ARTIFICIAL (parm))
9588 for (patparm = DECL_ARGUMENTS (pattern);
9589 patparm; patparm = DECL_CHAIN (patparm))
9590 if (DECL_ARTIFICIAL (patparm)
9591 && DECL_NAME (parm) == DECL_NAME (patparm))
9596 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9597 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9598 gcc_assert (DECL_PARM_INDEX (patparm)
9599 == DECL_PARM_INDEX (parm));
9605 /* Substitute ARGS into the vector or list of template arguments T. */
9608 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9611 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9614 if (t == error_mark_node)
9615 return error_mark_node;
9617 len = TREE_VEC_LENGTH (t);
9618 elts = XALLOCAVEC (tree, len);
9620 for (i = 0; i < len; i++)
9622 tree orig_arg = TREE_VEC_ELT (t, i);
9625 if (TREE_CODE (orig_arg) == TREE_VEC)
9626 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9627 else if (PACK_EXPANSION_P (orig_arg))
9629 /* Substitute into an expansion expression. */
9630 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9632 if (TREE_CODE (new_arg) == TREE_VEC)
9633 /* Add to the expanded length adjustment the number of
9634 expanded arguments. We subtract one from this
9635 measurement, because the argument pack expression
9636 itself is already counted as 1 in
9637 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9638 the argument pack is empty. */
9639 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9641 else if (ARGUMENT_PACK_P (orig_arg))
9643 /* Substitute into each of the arguments. */
9644 new_arg = TYPE_P (orig_arg)
9645 ? cxx_make_type (TREE_CODE (orig_arg))
9646 : make_node (TREE_CODE (orig_arg));
9648 SET_ARGUMENT_PACK_ARGS (
9650 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9651 args, complain, in_decl));
9653 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9654 new_arg = error_mark_node;
9656 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9657 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9659 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9661 if (TREE_TYPE (new_arg) == error_mark_node)
9662 new_arg = error_mark_node;
9666 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9668 if (new_arg == error_mark_node)
9669 return error_mark_node;
9672 if (new_arg != orig_arg)
9679 /* Make space for the expanded arguments coming from template
9681 t = make_tree_vec (len + expanded_len_adjust);
9682 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9683 arguments for a member template.
9684 In that case each TREE_VEC in ORIG_T represents a level of template
9685 arguments, and ORIG_T won't carry any non defaulted argument count.
9686 It will rather be the nested TREE_VECs that will carry one.
9687 In other words, ORIG_T carries a non defaulted argument count only
9688 if it doesn't contain any nested TREE_VEC. */
9689 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9691 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9692 count += expanded_len_adjust;
9693 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9695 for (i = 0, out = 0; i < len; i++)
9697 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9698 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9699 && TREE_CODE (elts[i]) == TREE_VEC)
9703 /* Now expand the template argument pack "in place". */
9704 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9705 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9709 TREE_VEC_ELT (t, out) = elts[i];
9717 /* Return the result of substituting ARGS into the template parameters
9718 given by PARMS. If there are m levels of ARGS and m + n levels of
9719 PARMS, then the result will contain n levels of PARMS. For
9720 example, if PARMS is `template <class T> template <class U>
9721 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9722 result will be `template <int*, double, class V>'. */
9725 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9730 /* When substituting into a template, we must set
9731 PROCESSING_TEMPLATE_DECL as the template parameters may be
9732 dependent if they are based on one-another, and the dependency
9733 predicates are short-circuit outside of templates. */
9734 ++processing_template_decl;
9736 for (new_parms = &r;
9737 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9738 new_parms = &(TREE_CHAIN (*new_parms)),
9739 parms = TREE_CHAIN (parms))
9742 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9745 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9749 if (parms == error_mark_node)
9752 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9754 if (tuple == error_mark_node)
9757 TREE_VEC_ELT (new_vec, i) =
9758 tsubst_template_parm (tuple, args, complain);
9762 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9763 - TMPL_ARGS_DEPTH (args)),
9764 new_vec, NULL_TREE);
9767 --processing_template_decl;
9772 /* Return the result of substituting ARGS into one template parameter
9773 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9774 parameter and which TREE_PURPOSE is the default argument of the
9775 template parameter. */
9778 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9780 tree default_value, parm_decl;
9782 if (args == NULL_TREE
9784 || t == error_mark_node)
9787 gcc_assert (TREE_CODE (t) == TREE_LIST);
9789 default_value = TREE_PURPOSE (t);
9790 parm_decl = TREE_VALUE (t);
9792 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9793 if (TREE_CODE (parm_decl) == PARM_DECL
9794 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9795 parm_decl = error_mark_node;
9796 default_value = tsubst_template_arg (default_value, args,
9797 complain, NULL_TREE);
9799 return build_tree_list (default_value, parm_decl);
9802 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9803 type T. If T is not an aggregate or enumeration type, it is
9804 handled as if by tsubst. IN_DECL is as for tsubst. If
9805 ENTERING_SCOPE is nonzero, T is the context for a template which
9806 we are presently tsubst'ing. Return the substituted value. */
9809 tsubst_aggr_type (tree t,
9811 tsubst_flags_t complain,
9818 switch (TREE_CODE (t))
9821 if (TYPE_PTRMEMFUNC_P (t))
9822 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9824 /* Else fall through. */
9827 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9832 int saved_unevaluated_operand;
9833 int saved_inhibit_evaluation_warnings;
9835 /* In "sizeof(X<I>)" we need to evaluate "I". */
9836 saved_unevaluated_operand = cp_unevaluated_operand;
9837 cp_unevaluated_operand = 0;
9838 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9839 c_inhibit_evaluation_warnings = 0;
9841 /* First, determine the context for the type we are looking
9843 context = TYPE_CONTEXT (t);
9844 if (context && TYPE_P (context))
9846 context = tsubst_aggr_type (context, args, complain,
9847 in_decl, /*entering_scope=*/1);
9848 /* If context is a nested class inside a class template,
9849 it may still need to be instantiated (c++/33959). */
9850 context = complete_type (context);
9853 /* Then, figure out what arguments are appropriate for the
9854 type we are trying to find. For example, given:
9856 template <class T> struct S;
9857 template <class T, class U> void f(T, U) { S<U> su; }
9859 and supposing that we are instantiating f<int, double>,
9860 then our ARGS will be {int, double}, but, when looking up
9861 S we only want {double}. */
9862 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9864 if (argvec == error_mark_node)
9865 r = error_mark_node;
9868 r = lookup_template_class (t, argvec, in_decl, context,
9869 entering_scope, complain);
9870 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9873 cp_unevaluated_operand = saved_unevaluated_operand;
9874 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9879 /* This is not a template type, so there's nothing to do. */
9883 return tsubst (t, args, complain, in_decl);
9887 /* Substitute into the default argument ARG (a default argument for
9888 FN), which has the indicated TYPE. */
9891 tsubst_default_argument (tree fn, tree type, tree arg)
9893 tree saved_class_ptr = NULL_TREE;
9894 tree saved_class_ref = NULL_TREE;
9896 /* This can happen in invalid code. */
9897 if (TREE_CODE (arg) == DEFAULT_ARG)
9900 /* This default argument came from a template. Instantiate the
9901 default argument here, not in tsubst. In the case of
9910 we must be careful to do name lookup in the scope of S<T>,
9911 rather than in the current class. */
9912 push_access_scope (fn);
9913 /* The "this" pointer is not valid in a default argument. */
9916 saved_class_ptr = current_class_ptr;
9917 cp_function_chain->x_current_class_ptr = NULL_TREE;
9918 saved_class_ref = current_class_ref;
9919 cp_function_chain->x_current_class_ref = NULL_TREE;
9922 push_deferring_access_checks(dk_no_deferred);
9923 /* The default argument expression may cause implicitly defined
9924 member functions to be synthesized, which will result in garbage
9925 collection. We must treat this situation as if we were within
9926 the body of function so as to avoid collecting live data on the
9929 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9930 tf_warning_or_error, NULL_TREE,
9931 /*integral_constant_expression_p=*/false);
9933 pop_deferring_access_checks();
9935 /* Restore the "this" pointer. */
9938 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9939 cp_function_chain->x_current_class_ref = saved_class_ref;
9942 /* Make sure the default argument is reasonable. */
9943 arg = check_default_argument (type, arg);
9945 pop_access_scope (fn);
9950 /* Substitute into all the default arguments for FN. */
9953 tsubst_default_arguments (tree fn)
9958 tmpl_args = DECL_TI_ARGS (fn);
9960 /* If this function is not yet instantiated, we certainly don't need
9961 its default arguments. */
9962 if (uses_template_parms (tmpl_args))
9964 /* Don't do this again for clones. */
9965 if (DECL_CLONED_FUNCTION_P (fn))
9968 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9970 arg = TREE_CHAIN (arg))
9971 if (TREE_PURPOSE (arg))
9972 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9974 TREE_PURPOSE (arg));
9977 /* Substitute the ARGS into the T, which is a _DECL. Return the
9978 result of the substitution. Issue error and warning messages under
9979 control of COMPLAIN. */
9982 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9984 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9985 location_t saved_loc;
9990 /* Set the filename and linenumber to improve error-reporting. */
9991 saved_loc = input_location;
9992 input_location = DECL_SOURCE_LOCATION (t);
9994 switch (TREE_CODE (t))
9998 /* We can get here when processing a member function template,
9999 member class template, or template template parameter. */
10000 tree decl = DECL_TEMPLATE_RESULT (t);
10005 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10007 /* Template template parameter is treated here. */
10008 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10009 if (new_type == error_mark_node)
10010 RETURN (error_mark_node);
10013 DECL_CHAIN (r) = NULL_TREE;
10014 TREE_TYPE (r) = new_type;
10015 DECL_TEMPLATE_RESULT (r)
10016 = build_decl (DECL_SOURCE_LOCATION (decl),
10017 TYPE_DECL, DECL_NAME (decl), new_type);
10018 DECL_TEMPLATE_PARMS (r)
10019 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10021 TYPE_NAME (new_type) = r;
10025 /* We might already have an instance of this template.
10026 The ARGS are for the surrounding class type, so the
10027 full args contain the tsubst'd args for the context,
10028 plus the innermost args from the template decl. */
10029 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10030 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10031 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10032 /* Because this is a template, the arguments will still be
10033 dependent, even after substitution. If
10034 PROCESSING_TEMPLATE_DECL is not set, the dependency
10035 predicates will short-circuit. */
10036 ++processing_template_decl;
10037 full_args = tsubst_template_args (tmpl_args, args,
10038 complain, in_decl);
10039 --processing_template_decl;
10040 if (full_args == error_mark_node)
10041 RETURN (error_mark_node);
10043 /* If this is a default template template argument,
10044 tsubst might not have changed anything. */
10045 if (full_args == tmpl_args)
10048 hash = hash_tmpl_and_args (t, full_args);
10049 spec = retrieve_specialization (t, full_args, hash);
10050 if (spec != NULL_TREE)
10056 /* Make a new template decl. It will be similar to the
10057 original, but will record the current template arguments.
10058 We also create a new function declaration, which is just
10059 like the old one, but points to this new template, rather
10060 than the old one. */
10062 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10063 DECL_CHAIN (r) = NULL_TREE;
10065 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10067 if (TREE_CODE (decl) == TYPE_DECL
10068 && !TYPE_DECL_ALIAS_P (decl))
10071 ++processing_template_decl;
10072 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10073 --processing_template_decl;
10074 if (new_type == error_mark_node)
10075 RETURN (error_mark_node);
10077 TREE_TYPE (r) = new_type;
10078 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10079 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10080 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10081 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10086 ++processing_template_decl;
10087 new_decl = tsubst (decl, args, complain, in_decl);
10088 --processing_template_decl;
10089 if (new_decl == error_mark_node)
10090 RETURN (error_mark_node);
10092 DECL_TEMPLATE_RESULT (r) = new_decl;
10093 DECL_TI_TEMPLATE (new_decl) = r;
10094 TREE_TYPE (r) = TREE_TYPE (new_decl);
10095 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10096 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10099 SET_DECL_IMPLICIT_INSTANTIATION (r);
10100 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10101 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10103 /* The template parameters for this new template are all the
10104 template parameters for the old template, except the
10105 outermost level of parameters. */
10106 DECL_TEMPLATE_PARMS (r)
10107 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10110 if (PRIMARY_TEMPLATE_P (t))
10111 DECL_PRIMARY_TEMPLATE (r) = r;
10113 if (TREE_CODE (decl) != TYPE_DECL)
10114 /* Record this non-type partial instantiation. */
10115 register_specialization (r, t,
10116 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10121 case FUNCTION_DECL:
10124 tree argvec = NULL_TREE;
10132 /* Nobody should be tsubst'ing into non-template functions. */
10133 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10135 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10140 /* If T is not dependent, just return it. We have to
10141 increment PROCESSING_TEMPLATE_DECL because
10142 value_dependent_expression_p assumes that nothing is
10143 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10144 ++processing_template_decl;
10145 dependent_p = value_dependent_expression_p (t);
10146 --processing_template_decl;
10150 /* Calculate the most general template of which R is a
10151 specialization, and the complete set of arguments used to
10153 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10154 argvec = tsubst_template_args (DECL_TI_ARGS
10155 (DECL_TEMPLATE_RESULT
10156 (DECL_TI_TEMPLATE (t))),
10157 args, complain, in_decl);
10158 if (argvec == error_mark_node)
10159 RETURN (error_mark_node);
10161 /* Check to see if we already have this specialization. */
10162 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10163 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10171 /* We can see more levels of arguments than parameters if
10172 there was a specialization of a member template, like
10175 template <class T> struct S { template <class U> void f(); }
10176 template <> template <class U> void S<int>::f(U);
10178 Here, we'll be substituting into the specialization,
10179 because that's where we can find the code we actually
10180 want to generate, but we'll have enough arguments for
10181 the most general template.
10183 We also deal with the peculiar case:
10185 template <class T> struct S {
10186 template <class U> friend void f();
10188 template <class U> void f() {}
10190 template void f<double>();
10192 Here, the ARGS for the instantiation of will be {int,
10193 double}. But, we only need as many ARGS as there are
10194 levels of template parameters in CODE_PATTERN. We are
10195 careful not to get fooled into reducing the ARGS in
10198 template <class T> struct S { template <class U> void f(U); }
10199 template <class T> template <> void S<T>::f(int) {}
10201 which we can spot because the pattern will be a
10202 specialization in this case. */
10203 args_depth = TMPL_ARGS_DEPTH (args);
10205 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10206 if (args_depth > parms_depth
10207 && !DECL_TEMPLATE_SPECIALIZATION (t))
10208 args = get_innermost_template_args (args, parms_depth);
10212 /* This special case arises when we have something like this:
10214 template <class T> struct S {
10215 friend void f<int>(int, double);
10218 Here, the DECL_TI_TEMPLATE for the friend declaration
10219 will be an IDENTIFIER_NODE. We are being called from
10220 tsubst_friend_function, and we want only to create a
10221 new decl (R) with appropriate types so that we can call
10222 determine_specialization. */
10223 gen_tmpl = NULL_TREE;
10226 if (DECL_CLASS_SCOPE_P (t))
10228 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10232 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10233 complain, t, /*entering_scope=*/1);
10238 ctx = DECL_CONTEXT (t);
10240 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10241 if (type == error_mark_node)
10242 RETURN (error_mark_node);
10244 /* We do NOT check for matching decls pushed separately at this
10245 point, as they may not represent instantiations of this
10246 template, and in any case are considered separate under the
10249 DECL_USE_TEMPLATE (r) = 0;
10250 TREE_TYPE (r) = type;
10251 /* Clear out the mangled name and RTL for the instantiation. */
10252 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10253 SET_DECL_RTL (r, NULL);
10254 /* Leave DECL_INITIAL set on deleted instantiations. */
10255 if (!DECL_DELETED_FN (r))
10256 DECL_INITIAL (r) = NULL_TREE;
10257 DECL_CONTEXT (r) = ctx;
10259 if (member && DECL_CONV_FN_P (r))
10260 /* Type-conversion operator. Reconstruct the name, in
10261 case it's the name of one of the template's parameters. */
10262 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10264 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10266 DECL_RESULT (r) = NULL_TREE;
10268 TREE_STATIC (r) = 0;
10269 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10270 DECL_EXTERNAL (r) = 1;
10271 /* If this is an instantiation of a function with internal
10272 linkage, we already know what object file linkage will be
10273 assigned to the instantiation. */
10274 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10275 DECL_DEFER_OUTPUT (r) = 0;
10276 DECL_CHAIN (r) = NULL_TREE;
10277 DECL_PENDING_INLINE_INFO (r) = 0;
10278 DECL_PENDING_INLINE_P (r) = 0;
10279 DECL_SAVED_TREE (r) = NULL_TREE;
10280 DECL_STRUCT_FUNCTION (r) = NULL;
10282 /* We'll re-clone as appropriate in instantiate_template. */
10283 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10285 /* If we aren't complaining now, return on error before we register
10286 the specialization so that we'll complain eventually. */
10287 if ((complain & tf_error) == 0
10288 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10289 && !grok_op_properties (r, /*complain=*/false))
10290 RETURN (error_mark_node);
10292 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10293 this in the special friend case mentioned above where
10294 GEN_TMPL is NULL. */
10297 DECL_TEMPLATE_INFO (r)
10298 = build_template_info (gen_tmpl, argvec);
10299 SET_DECL_IMPLICIT_INSTANTIATION (r);
10300 register_specialization (r, gen_tmpl, argvec, false, hash);
10302 /* We're not supposed to instantiate default arguments
10303 until they are called, for a template. But, for a
10306 template <class T> void f ()
10307 { extern void g(int i = T()); }
10309 we should do the substitution when the template is
10310 instantiated. We handle the member function case in
10311 instantiate_class_template since the default arguments
10312 might refer to other members of the class. */
10314 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10315 && !uses_template_parms (argvec))
10316 tsubst_default_arguments (r);
10319 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10321 /* Copy the list of befriending classes. */
10322 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10324 friends = &TREE_CHAIN (*friends))
10326 *friends = copy_node (*friends);
10327 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10332 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10334 maybe_retrofit_in_chrg (r);
10335 if (DECL_CONSTRUCTOR_P (r))
10336 grok_ctor_properties (ctx, r);
10337 /* If this is an instantiation of a member template, clone it.
10338 If it isn't, that'll be handled by
10339 clone_constructors_and_destructors. */
10340 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10341 clone_function_decl (r, /*update_method_vec_p=*/0);
10343 else if ((complain & tf_error) != 0
10344 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10345 && !grok_op_properties (r, /*complain=*/true))
10346 RETURN (error_mark_node);
10348 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10349 SET_DECL_FRIEND_CONTEXT (r,
10350 tsubst (DECL_FRIEND_CONTEXT (t),
10351 args, complain, in_decl));
10353 /* Possibly limit visibility based on template args. */
10354 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10355 if (DECL_VISIBILITY_SPECIFIED (t))
10357 DECL_VISIBILITY_SPECIFIED (r) = 0;
10358 DECL_ATTRIBUTES (r)
10359 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10361 determine_visibility (r);
10362 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10363 && !processing_template_decl)
10364 defaulted_late_check (r);
10366 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10367 args, complain, in_decl);
10373 tree type = NULL_TREE;
10375 tree expanded_types = NULL_TREE;
10376 tree prev_r = NULL_TREE;
10377 tree first_r = NULL_TREE;
10379 if (FUNCTION_PARAMETER_PACK_P (t))
10381 /* If there is a local specialization that isn't a
10382 parameter pack, it means that we're doing a "simple"
10383 substitution from inside tsubst_pack_expansion. Just
10384 return the local specialization (which will be a single
10386 tree spec = retrieve_local_specialization (t);
10388 && TREE_CODE (spec) == PARM_DECL
10389 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10392 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10393 the parameters in this function parameter pack. */
10394 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10395 complain, in_decl);
10396 if (TREE_CODE (expanded_types) == TREE_VEC)
10398 len = TREE_VEC_LENGTH (expanded_types);
10400 /* Zero-length parameter packs are boring. Just substitute
10403 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10408 /* All we did was update the type. Make a note of that. */
10409 type = expanded_types;
10410 expanded_types = NULL_TREE;
10414 /* Loop through all of the parameter's we'll build. When T is
10415 a function parameter pack, LEN is the number of expanded
10416 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10418 for (i = 0; i < len; ++i)
10422 if (DECL_TEMPLATE_PARM_P (t))
10423 SET_DECL_TEMPLATE_PARM_P (r);
10425 if (expanded_types)
10426 /* We're on the Ith parameter of the function parameter
10429 /* An argument of a function parameter pack is not a parameter
10431 FUNCTION_PARAMETER_PACK_P (r) = false;
10433 /* Get the Ith type. */
10434 type = TREE_VEC_ELT (expanded_types, i);
10437 /* Rename the parameter to include the index. */
10439 make_ith_pack_parameter_name (DECL_NAME (r), i);
10442 /* We're dealing with a normal parameter. */
10443 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10445 type = type_decays_to (type);
10446 TREE_TYPE (r) = type;
10447 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10449 if (DECL_INITIAL (r))
10451 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10452 DECL_INITIAL (r) = TREE_TYPE (r);
10454 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10455 complain, in_decl);
10458 DECL_CONTEXT (r) = NULL_TREE;
10460 if (!DECL_TEMPLATE_PARM_P (r))
10461 DECL_ARG_TYPE (r) = type_passed_as (type);
10463 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10464 args, complain, in_decl);
10466 /* Keep track of the first new parameter we
10467 generate. That's what will be returned to the
10472 /* Build a proper chain of parameters when substituting
10473 into a function parameter pack. */
10475 DECL_CHAIN (prev_r) = r;
10478 if (DECL_CHAIN (t))
10479 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10480 complain, DECL_CHAIN (t));
10482 /* FIRST_R contains the start of the chain we've built. */
10492 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10493 if (type == error_mark_node)
10494 RETURN (error_mark_node);
10495 TREE_TYPE (r) = type;
10496 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10498 if (DECL_C_BIT_FIELD (r))
10499 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10500 non-bit-fields DECL_INITIAL is a non-static data member
10501 initializer, which gets deferred instantiation. */
10503 = tsubst_expr (DECL_INITIAL (t), args,
10505 /*integral_constant_expression_p=*/true);
10506 else if (DECL_INITIAL (t))
10508 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10509 NSDMI in perform_member_init. Still set DECL_INITIAL
10510 so that we know there is one. */
10511 DECL_INITIAL (r) = void_zero_node;
10512 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10513 retrofit_lang_decl (r);
10514 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10516 /* We don't have to set DECL_CONTEXT here; it is set by
10517 finish_member_declaration. */
10518 DECL_CHAIN (r) = NULL_TREE;
10519 if (VOID_TYPE_P (type))
10520 error ("instantiation of %q+D as type %qT", r, type);
10522 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10523 args, complain, in_decl);
10528 /* We reach here only for member using decls. */
10529 if (DECL_DEPENDENT_P (t))
10531 r = do_class_using_decl
10532 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10533 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10535 r = error_mark_node;
10538 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10539 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10545 DECL_CHAIN (r) = NULL_TREE;
10552 tree argvec = NULL_TREE;
10553 tree gen_tmpl = NULL_TREE;
10555 tree tmpl = NULL_TREE;
10557 tree type = NULL_TREE;
10560 if (TREE_CODE (t) == TYPE_DECL
10561 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10563 /* If this is the canonical decl, we don't have to
10564 mess with instantiations, and often we can't (for
10565 typename, template type parms and such). Note that
10566 TYPE_NAME is not correct for the above test if
10567 we've copied the type for a typedef. */
10568 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10569 if (type == error_mark_node)
10570 RETURN (error_mark_node);
10571 r = TYPE_NAME (type);
10575 /* Check to see if we already have the specialization we
10578 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10580 /* T is a static data member or namespace-scope entity.
10581 We have to substitute into namespace-scope variables
10582 (even though such entities are never templates) because
10585 template <class T> void f() { extern T t; }
10587 where the entity referenced is not known until
10588 instantiation time. */
10590 ctx = DECL_CONTEXT (t);
10591 if (DECL_CLASS_SCOPE_P (t))
10593 ctx = tsubst_aggr_type (ctx, args,
10595 in_decl, /*entering_scope=*/1);
10596 /* If CTX is unchanged, then T is in fact the
10597 specialization we want. That situation occurs when
10598 referencing a static data member within in its own
10599 class. We can use pointer equality, rather than
10600 same_type_p, because DECL_CONTEXT is always
10602 if (ctx == DECL_CONTEXT (t)
10603 && (TREE_CODE (t) != TYPE_DECL
10604 /* ... unless T is a member template; in which
10605 case our caller can be willing to create a
10606 specialization of that template represented
10608 || !(DECL_TI_TEMPLATE (t)
10609 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10615 tmpl = DECL_TI_TEMPLATE (t);
10616 gen_tmpl = most_general_template (tmpl);
10617 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10618 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10619 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10624 /* A local variable. */
10626 /* Subsequent calls to pushdecl will fill this in. */
10628 spec = retrieve_local_specialization (t);
10630 /* If we already have the specialization we need, there is
10631 nothing more to do. */
10638 /* Create a new node for the specialization we need. */
10640 if (type == NULL_TREE)
10642 if (is_typedef_decl (t))
10643 type = DECL_ORIGINAL_TYPE (t);
10645 type = TREE_TYPE (t);
10646 if (TREE_CODE (t) == VAR_DECL
10647 && VAR_HAD_UNKNOWN_BOUND (t)
10648 && type != error_mark_node)
10649 type = strip_array_domain (type);
10650 type = tsubst (type, args, complain, in_decl);
10652 if (TREE_CODE (r) == VAR_DECL)
10654 /* Even if the original location is out of scope, the
10655 newly substituted one is not. */
10656 DECL_DEAD_FOR_LOCAL (r) = 0;
10657 DECL_INITIALIZED_P (r) = 0;
10658 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10659 if (type == error_mark_node)
10660 RETURN (error_mark_node);
10661 if (TREE_CODE (type) == FUNCTION_TYPE)
10663 /* It may seem that this case cannot occur, since:
10668 declares a function, not a variable. However:
10671 template <typename T> void g() { T t; }
10672 template void g<f>();
10674 is an attempt to declare a variable with function
10676 error ("variable %qD has function type",
10677 /* R is not yet sufficiently initialized, so we
10678 just use its name. */
10680 RETURN (error_mark_node);
10682 type = complete_type (type);
10683 /* Wait until cp_finish_decl to set this again, to handle
10684 circular dependency (template/instantiate6.C). */
10685 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10686 type = check_var_type (DECL_NAME (r), type);
10688 if (DECL_HAS_VALUE_EXPR_P (t))
10690 tree ve = DECL_VALUE_EXPR (t);
10691 ve = tsubst_expr (ve, args, complain, in_decl,
10692 /*constant_expression_p=*/false);
10693 if (REFERENCE_REF_P (ve))
10695 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10696 ve = TREE_OPERAND (ve, 0);
10698 SET_DECL_VALUE_EXPR (r, ve);
10701 else if (DECL_SELF_REFERENCE_P (t))
10702 SET_DECL_SELF_REFERENCE_P (r);
10703 TREE_TYPE (r) = type;
10704 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10705 DECL_CONTEXT (r) = ctx;
10706 /* Clear out the mangled name and RTL for the instantiation. */
10707 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10708 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10709 SET_DECL_RTL (r, NULL);
10710 /* The initializer must not be expanded until it is required;
10711 see [temp.inst]. */
10712 DECL_INITIAL (r) = NULL_TREE;
10713 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10714 SET_DECL_RTL (r, NULL);
10715 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10716 if (TREE_CODE (r) == VAR_DECL)
10718 /* Possibly limit visibility based on template args. */
10719 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10720 if (DECL_VISIBILITY_SPECIFIED (t))
10722 DECL_VISIBILITY_SPECIFIED (r) = 0;
10723 DECL_ATTRIBUTES (r)
10724 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10726 determine_visibility (r);
10731 /* A static data member declaration is always marked
10732 external when it is declared in-class, even if an
10733 initializer is present. We mimic the non-template
10734 processing here. */
10735 DECL_EXTERNAL (r) = 1;
10737 register_specialization (r, gen_tmpl, argvec, false, hash);
10738 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10739 SET_DECL_IMPLICIT_INSTANTIATION (r);
10741 else if (cp_unevaluated_operand)
10743 /* We're substituting this var in a decltype outside of its
10744 scope, such as for a lambda return type. Don't add it to
10745 local_specializations, do perform auto deduction. */
10746 tree auto_node = type_uses_auto (type);
10750 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10751 /*constant_expression_p=*/false);
10752 init = resolve_nondeduced_context (init);
10753 TREE_TYPE (r) = type
10754 = do_auto_deduction (type, init, auto_node);
10758 register_local_specialization (r, t);
10760 DECL_CHAIN (r) = NULL_TREE;
10762 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10764 args, complain, in_decl);
10766 /* Preserve a typedef that names a type. */
10767 if (is_typedef_decl (r))
10769 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10770 set_underlying_type (r);
10773 layout_decl (r, 0);
10778 gcc_unreachable ();
10783 /* Restore the file and line information. */
10784 input_location = saved_loc;
10789 /* Substitute into the ARG_TYPES of a function type. */
10792 tsubst_arg_types (tree arg_types,
10794 tsubst_flags_t complain,
10797 tree remaining_arg_types;
10798 tree type = NULL_TREE;
10800 tree expanded_args = NULL_TREE;
10803 if (!arg_types || arg_types == void_list_node)
10806 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10807 args, complain, in_decl);
10808 if (remaining_arg_types == error_mark_node)
10809 return error_mark_node;
10811 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10813 /* For a pack expansion, perform substitution on the
10814 entire expression. Later on, we'll handle the arguments
10816 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10817 args, complain, in_decl);
10819 if (TREE_CODE (expanded_args) == TREE_VEC)
10820 /* So that we'll spin through the parameters, one by one. */
10821 i = TREE_VEC_LENGTH (expanded_args);
10824 /* We only partially substituted into the parameter
10825 pack. Our type is TYPE_PACK_EXPANSION. */
10826 type = expanded_args;
10827 expanded_args = NULL_TREE;
10835 type = TREE_VEC_ELT (expanded_args, i);
10837 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10839 if (type == error_mark_node)
10840 return error_mark_node;
10841 if (VOID_TYPE_P (type))
10843 if (complain & tf_error)
10845 error ("invalid parameter type %qT", type);
10847 error ("in declaration %q+D", in_decl);
10849 return error_mark_node;
10852 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10853 top-level qualifiers as required. */
10854 type = cv_unqualified (type_decays_to (type));
10856 /* We do not substitute into default arguments here. The standard
10857 mandates that they be instantiated only when needed, which is
10858 done in build_over_call. */
10859 default_arg = TREE_PURPOSE (arg_types);
10861 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10863 /* We've instantiated a template before its default arguments
10864 have been parsed. This can happen for a nested template
10865 class, and is not an error unless we require the default
10866 argument in a call of this function. */
10867 remaining_arg_types =
10868 tree_cons (default_arg, type, remaining_arg_types);
10869 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10870 remaining_arg_types);
10873 remaining_arg_types =
10874 hash_tree_cons (default_arg, type, remaining_arg_types);
10877 return remaining_arg_types;
10880 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10881 *not* handle the exception-specification for FNTYPE, because the
10882 initial substitution of explicitly provided template parameters
10883 during argument deduction forbids substitution into the
10884 exception-specification:
10888 All references in the function type of the function template to the
10889 corresponding template parameters are replaced by the specified tem-
10890 plate argument values. If a substitution in a template parameter or
10891 in the function type of the function template results in an invalid
10892 type, type deduction fails. [Note: The equivalent substitution in
10893 exception specifications is done only when the function is instanti-
10894 ated, at which point a program is ill-formed if the substitution
10895 results in an invalid type.] */
10898 tsubst_function_type (tree t,
10900 tsubst_flags_t complain,
10907 /* The TYPE_CONTEXT is not used for function/method types. */
10908 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10910 /* Substitute the return type. */
10911 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10912 if (return_type == error_mark_node)
10913 return error_mark_node;
10914 /* The standard does not presently indicate that creation of a
10915 function type with an invalid return type is a deduction failure.
10916 However, that is clearly analogous to creating an array of "void"
10917 or a reference to a reference. This is core issue #486. */
10918 if (TREE_CODE (return_type) == ARRAY_TYPE
10919 || TREE_CODE (return_type) == FUNCTION_TYPE)
10921 if (complain & tf_error)
10923 if (TREE_CODE (return_type) == ARRAY_TYPE)
10924 error ("function returning an array");
10926 error ("function returning a function");
10928 return error_mark_node;
10931 /* Substitute the argument types. */
10932 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10933 complain, in_decl);
10934 if (arg_types == error_mark_node)
10935 return error_mark_node;
10937 /* Construct a new type node and return it. */
10938 if (TREE_CODE (t) == FUNCTION_TYPE)
10940 fntype = build_function_type (return_type, arg_types);
10941 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10945 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10946 if (! MAYBE_CLASS_TYPE_P (r))
10950 Type deduction may fail for any of the following
10953 -- Attempting to create "pointer to member of T" when T
10954 is not a class type. */
10955 if (complain & tf_error)
10956 error ("creating pointer to member function of non-class type %qT",
10958 return error_mark_node;
10961 fntype = build_method_type_directly (r, return_type,
10962 TREE_CHAIN (arg_types));
10964 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10969 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10970 ARGS into that specification, and return the substituted
10971 specification. If there is no specification, return NULL_TREE. */
10974 tsubst_exception_specification (tree fntype,
10976 tsubst_flags_t complain,
10983 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10984 new_specs = NULL_TREE;
10985 if (specs && TREE_PURPOSE (specs))
10987 /* A noexcept-specifier. */
10988 tree expr = TREE_PURPOSE (specs);
10989 if (expr == boolean_true_node || expr == boolean_false_node)
10993 /* Defer instantiation of noexcept-specifiers to avoid
10994 excessive instantiations (c++/49107). */
10995 new_specs = make_node (DEFERRED_NOEXCEPT);
10996 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
10998 /* We already partially instantiated this member template,
10999 so combine the new args with the old. */
11000 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11001 = DEFERRED_NOEXCEPT_PATTERN (expr);
11002 DEFERRED_NOEXCEPT_ARGS (new_specs)
11003 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11007 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11008 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11012 new_specs = tsubst_copy_and_build
11013 (expr, args, complain, in_decl, /*function_p=*/false,
11014 /*integral_constant_expression_p=*/true);
11015 new_specs = build_noexcept_spec (new_specs, complain);
11019 if (! TREE_VALUE (specs))
11026 tree expanded_specs = NULL_TREE;
11028 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11030 /* Expand the pack expansion type. */
11031 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11035 if (expanded_specs == error_mark_node)
11036 return error_mark_node;
11037 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11038 len = TREE_VEC_LENGTH (expanded_specs);
11041 /* We're substituting into a member template, so
11042 we got a TYPE_PACK_EXPANSION back. Add that
11043 expansion and move on. */
11044 gcc_assert (TREE_CODE (expanded_specs)
11045 == TYPE_PACK_EXPANSION);
11046 new_specs = add_exception_specifier (new_specs,
11049 specs = TREE_CHAIN (specs);
11054 for (i = 0; i < len; ++i)
11056 if (expanded_specs)
11057 spec = TREE_VEC_ELT (expanded_specs, i);
11059 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11060 if (spec == error_mark_node)
11062 new_specs = add_exception_specifier (new_specs, spec,
11066 specs = TREE_CHAIN (specs);
11072 /* Take the tree structure T and replace template parameters used
11073 therein with the argument vector ARGS. IN_DECL is an associated
11074 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11075 Issue error and warning messages under control of COMPLAIN. Note
11076 that we must be relatively non-tolerant of extensions here, in
11077 order to preserve conformance; if we allow substitutions that
11078 should not be allowed, we may allow argument deductions that should
11079 not succeed, and therefore report ambiguous overload situations
11080 where there are none. In theory, we could allow the substitution,
11081 but indicate that it should have failed, and allow our caller to
11082 make sure that the right thing happens, but we don't try to do this
11085 This function is used for dealing with types, decls and the like;
11086 for expressions, use tsubst_expr or tsubst_copy. */
11089 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11091 enum tree_code code;
11092 tree type, r = NULL_TREE;
11094 if (t == NULL_TREE || t == error_mark_node
11095 || t == integer_type_node
11096 || t == void_type_node
11097 || t == char_type_node
11098 || t == unknown_type_node
11099 || TREE_CODE (t) == NAMESPACE_DECL
11100 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11104 return tsubst_decl (t, args, complain);
11106 if (args == NULL_TREE)
11109 code = TREE_CODE (t);
11111 if (code == IDENTIFIER_NODE)
11112 type = IDENTIFIER_TYPE_VALUE (t);
11114 type = TREE_TYPE (t);
11116 gcc_assert (type != unknown_type_node);
11118 /* Reuse typedefs. We need to do this to handle dependent attributes,
11119 such as attribute aligned. */
11121 && typedef_variant_p (t))
11123 tree decl = TYPE_NAME (t);
11125 if (TYPE_DECL_ALIAS_P (decl)
11126 && DECL_LANG_SPECIFIC (decl)
11127 && DECL_TEMPLATE_INFO (decl)
11128 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11130 /* DECL represents an alias template and we want to
11131 instantiate it. Let's substitute our arguments for the
11132 template parameters into the declaration and get the
11134 r = tsubst (decl, args, complain, decl);
11136 else if (DECL_CLASS_SCOPE_P (decl)
11137 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11138 && uses_template_parms (DECL_CONTEXT (decl)))
11140 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11141 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11142 r = retrieve_specialization (tmpl, gen_args, 0);
11144 else if (DECL_FUNCTION_SCOPE_P (decl)
11145 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11146 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11147 r = retrieve_local_specialization (decl);
11149 /* The typedef is from a non-template context. */
11155 r = cp_build_qualified_type_real
11156 (r, cp_type_quals (t) | cp_type_quals (r),
11157 complain | tf_ignore_bad_quals);
11160 /* Else we must be instantiating the typedef, so fall through. */
11164 && code != TYPENAME_TYPE
11165 && code != TEMPLATE_TYPE_PARM
11166 && code != IDENTIFIER_NODE
11167 && code != FUNCTION_TYPE
11168 && code != METHOD_TYPE)
11169 type = tsubst (type, args, complain, in_decl);
11170 if (type == error_mark_node)
11171 return error_mark_node;
11177 case ENUMERAL_TYPE:
11178 return tsubst_aggr_type (t, args, complain, in_decl,
11179 /*entering_scope=*/0);
11182 case IDENTIFIER_NODE:
11193 if (t == integer_type_node)
11196 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11197 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11201 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11203 max = tsubst_expr (omax, args, complain, in_decl,
11204 /*integral_constant_expression_p=*/false);
11206 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11208 if (TREE_CODE (max) == NOP_EXPR
11209 && TREE_SIDE_EFFECTS (omax)
11210 && !TREE_TYPE (max))
11211 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11213 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11214 with TREE_SIDE_EFFECTS that indicates this is not an integral
11215 constant expression. */
11216 if (processing_template_decl
11217 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11219 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11220 TREE_SIDE_EFFECTS (max) = 1;
11223 return compute_array_index_type (NULL_TREE, max, complain);
11226 case TEMPLATE_TYPE_PARM:
11227 case TEMPLATE_TEMPLATE_PARM:
11228 case BOUND_TEMPLATE_TEMPLATE_PARM:
11229 case TEMPLATE_PARM_INDEX:
11234 tree arg = NULL_TREE;
11238 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11239 template_parm_level_and_index (t, &level, &idx);
11241 levels = TMPL_ARGS_DEPTH (args);
11242 if (level <= levels)
11244 arg = TMPL_ARG (args, level, idx);
11246 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11247 /* See through ARGUMENT_PACK_SELECT arguments. */
11248 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11251 if (arg == error_mark_node)
11252 return error_mark_node;
11253 else if (arg != NULL_TREE)
11255 if (ARGUMENT_PACK_P (arg))
11256 /* If ARG is an argument pack, we don't actually want to
11257 perform a substitution here, because substitutions
11258 for argument packs are only done
11259 element-by-element. We can get to this point when
11260 substituting the type of a non-type template
11261 parameter pack, when that type actually contains
11262 template parameter packs from an outer template, e.g.,
11264 template<typename... Types> struct A {
11265 template<Types... Values> struct B { };
11269 if (code == TEMPLATE_TYPE_PARM)
11272 gcc_assert (TYPE_P (arg));
11274 quals = cp_type_quals (arg) | cp_type_quals (t);
11276 return cp_build_qualified_type_real
11277 (arg, quals, complain | tf_ignore_bad_quals);
11279 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11281 /* We are processing a type constructed from a
11282 template template parameter. */
11283 tree argvec = tsubst (TYPE_TI_ARGS (t),
11284 args, complain, in_decl);
11285 if (argvec == error_mark_node)
11286 return error_mark_node;
11288 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11289 || TREE_CODE (arg) == TEMPLATE_DECL
11290 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11292 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11293 /* Consider this code:
11295 template <template <class> class Template>
11297 template <class Arg> using Bind = Template<Arg>;
11300 template <template <class> class Template, class Arg>
11301 using Instantiate = Template<Arg>; //#0
11303 template <template <class> class Template,
11306 Instantiate<Internal<Template>::template Bind,
11309 When #1 is parsed, the
11310 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11311 parameter `Template' in #0 matches the
11312 UNBOUND_CLASS_TEMPLATE representing the argument
11313 `Internal<Template>::template Bind'; We then want
11314 to assemble the type `Bind<Argument>' that can't
11315 be fully created right now, because
11316 `Internal<Template>' not being complete, the Bind
11317 template cannot be looked up in that context. So
11318 we need to "store" `Bind<Argument>' for later
11319 when the context of Bind becomes complete. Let's
11320 store that in a TYPENAME_TYPE. */
11321 return make_typename_type (TYPE_CONTEXT (arg),
11322 build_nt (TEMPLATE_ID_EXPR,
11323 TYPE_IDENTIFIER (arg),
11328 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11329 are resolving nested-types in the signature of a
11330 member function templates. Otherwise ARG is a
11331 TEMPLATE_DECL and is the real template to be
11333 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11334 arg = TYPE_NAME (arg);
11336 r = lookup_template_class (arg,
11338 DECL_CONTEXT (arg),
11339 /*entering_scope=*/0,
11341 return cp_build_qualified_type_real
11342 (r, cp_type_quals (t), complain);
11345 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11346 return convert_from_reference (unshare_expr (arg));
11350 /* This can happen during the attempted tsubst'ing in
11351 unify. This means that we don't yet have any information
11352 about the template parameter in question. */
11355 /* If we get here, we must have been looking at a parm for a
11356 more deeply nested template. Make a new version of this
11357 template parameter, but with a lower level. */
11360 case TEMPLATE_TYPE_PARM:
11361 case TEMPLATE_TEMPLATE_PARM:
11362 case BOUND_TEMPLATE_TEMPLATE_PARM:
11363 if (cp_type_quals (t))
11365 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11366 r = cp_build_qualified_type_real
11367 (r, cp_type_quals (t),
11368 complain | (code == TEMPLATE_TYPE_PARM
11369 ? tf_ignore_bad_quals : 0));
11374 TEMPLATE_TYPE_PARM_INDEX (r)
11375 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11376 r, levels, args, complain);
11377 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11378 TYPE_MAIN_VARIANT (r) = r;
11379 TYPE_POINTER_TO (r) = NULL_TREE;
11380 TYPE_REFERENCE_TO (r) = NULL_TREE;
11382 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11383 /* We have reduced the level of the template
11384 template parameter, but not the levels of its
11385 template parameters, so canonical_type_parameter
11386 will not be able to find the canonical template
11387 template parameter for this level. Thus, we
11388 require structural equality checking to compare
11389 TEMPLATE_TEMPLATE_PARMs. */
11390 SET_TYPE_STRUCTURAL_EQUALITY (r);
11391 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11392 SET_TYPE_STRUCTURAL_EQUALITY (r);
11394 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11396 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11398 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11399 complain, in_decl);
11400 if (argvec == error_mark_node)
11401 return error_mark_node;
11403 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11404 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11409 case TEMPLATE_PARM_INDEX:
11410 r = reduce_template_parm_level (t, type, levels, args, complain);
11414 gcc_unreachable ();
11422 tree purpose, value, chain;
11424 if (t == void_list_node)
11427 purpose = TREE_PURPOSE (t);
11430 purpose = tsubst (purpose, args, complain, in_decl);
11431 if (purpose == error_mark_node)
11432 return error_mark_node;
11434 value = TREE_VALUE (t);
11437 value = tsubst (value, args, complain, in_decl);
11438 if (value == error_mark_node)
11439 return error_mark_node;
11441 chain = TREE_CHAIN (t);
11442 if (chain && chain != void_type_node)
11444 chain = tsubst (chain, args, complain, in_decl);
11445 if (chain == error_mark_node)
11446 return error_mark_node;
11448 if (purpose == TREE_PURPOSE (t)
11449 && value == TREE_VALUE (t)
11450 && chain == TREE_CHAIN (t))
11452 return hash_tree_cons (purpose, value, chain);
11456 /* We should never be tsubsting a binfo. */
11457 gcc_unreachable ();
11460 /* A vector of template arguments. */
11461 gcc_assert (!type);
11462 return tsubst_template_args (t, args, complain, in_decl);
11465 case REFERENCE_TYPE:
11467 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11472 Type deduction may fail for any of the following
11475 -- Attempting to create a pointer to reference type.
11476 -- Attempting to create a reference to a reference type or
11477 a reference to void.
11479 Core issue 106 says that creating a reference to a reference
11480 during instantiation is no longer a cause for failure. We
11481 only enforce this check in strict C++98 mode. */
11482 if ((TREE_CODE (type) == REFERENCE_TYPE
11483 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11484 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11486 static location_t last_loc;
11488 /* We keep track of the last time we issued this error
11489 message to avoid spewing a ton of messages during a
11490 single bad template instantiation. */
11491 if (complain & tf_error
11492 && last_loc != input_location)
11494 if (TREE_CODE (type) == VOID_TYPE)
11495 error ("forming reference to void");
11496 else if (code == POINTER_TYPE)
11497 error ("forming pointer to reference type %qT", type);
11499 error ("forming reference to reference type %qT", type);
11500 last_loc = input_location;
11503 return error_mark_node;
11505 else if (code == POINTER_TYPE)
11507 r = build_pointer_type (type);
11508 if (TREE_CODE (type) == METHOD_TYPE)
11509 r = build_ptrmemfunc_type (r);
11511 else if (TREE_CODE (type) == REFERENCE_TYPE)
11512 /* In C++0x, during template argument substitution, when there is an
11513 attempt to create a reference to a reference type, reference
11514 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11516 "If a template-argument for a template-parameter T names a type
11517 that is a reference to a type A, an attempt to create the type
11518 'lvalue reference to cv T' creates the type 'lvalue reference to
11519 A,' while an attempt to create the type type rvalue reference to
11520 cv T' creates the type T"
11522 r = cp_build_reference_type
11524 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11526 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11527 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11529 if (r != error_mark_node)
11530 /* Will this ever be needed for TYPE_..._TO values? */
11537 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11538 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11542 Type deduction may fail for any of the following
11545 -- Attempting to create "pointer to member of T" when T
11546 is not a class type. */
11547 if (complain & tf_error)
11548 error ("creating pointer to member of non-class type %qT", r);
11549 return error_mark_node;
11551 if (TREE_CODE (type) == REFERENCE_TYPE)
11553 if (complain & tf_error)
11554 error ("creating pointer to member reference type %qT", type);
11555 return error_mark_node;
11557 if (TREE_CODE (type) == VOID_TYPE)
11559 if (complain & tf_error)
11560 error ("creating pointer to member of type void");
11561 return error_mark_node;
11563 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11564 if (TREE_CODE (type) == FUNCTION_TYPE)
11566 /* The type of the implicit object parameter gets its
11567 cv-qualifiers from the FUNCTION_TYPE. */
11569 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11570 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11571 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11575 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11579 case FUNCTION_TYPE:
11584 fntype = tsubst_function_type (t, args, complain, in_decl);
11585 if (fntype == error_mark_node)
11586 return error_mark_node;
11588 /* Substitute the exception specification. */
11589 specs = tsubst_exception_specification (t, args, complain,
11590 in_decl, /*defer_ok*/true);
11591 if (specs == error_mark_node)
11592 return error_mark_node;
11594 fntype = build_exception_variant (fntype, specs);
11599 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11600 if (domain == error_mark_node)
11601 return error_mark_node;
11603 /* As an optimization, we avoid regenerating the array type if
11604 it will obviously be the same as T. */
11605 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11608 /* These checks should match the ones in grokdeclarator.
11612 The deduction may fail for any of the following reasons:
11614 -- Attempting to create an array with an element type that
11615 is void, a function type, or a reference type, or [DR337]
11616 an abstract class type. */
11617 if (TREE_CODE (type) == VOID_TYPE
11618 || TREE_CODE (type) == FUNCTION_TYPE
11619 || TREE_CODE (type) == REFERENCE_TYPE)
11621 if (complain & tf_error)
11622 error ("creating array of %qT", type);
11623 return error_mark_node;
11625 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11627 if (complain & tf_error)
11628 error ("creating array of %qT, which is an abstract class type",
11630 return error_mark_node;
11633 r = build_cplus_array_type (type, domain);
11635 if (TYPE_USER_ALIGN (t))
11637 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11638 TYPE_USER_ALIGN (r) = 1;
11644 case TYPENAME_TYPE:
11646 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11647 in_decl, /*entering_scope=*/1);
11648 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11649 complain, in_decl);
11651 if (ctx == error_mark_node || f == error_mark_node)
11652 return error_mark_node;
11654 if (!MAYBE_CLASS_TYPE_P (ctx))
11656 if (complain & tf_error)
11657 error ("%qT is not a class, struct, or union type", ctx);
11658 return error_mark_node;
11660 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11662 /* Normally, make_typename_type does not require that the CTX
11663 have complete type in order to allow things like:
11665 template <class T> struct S { typename S<T>::X Y; };
11667 But, such constructs have already been resolved by this
11668 point, so here CTX really should have complete type, unless
11669 it's a partial instantiation. */
11670 ctx = complete_type (ctx);
11671 if (!COMPLETE_TYPE_P (ctx))
11673 if (complain & tf_error)
11674 cxx_incomplete_type_error (NULL_TREE, ctx);
11675 return error_mark_node;
11679 f = make_typename_type (ctx, f, typename_type,
11680 (complain & tf_error) | tf_keep_type_decl);
11681 if (f == error_mark_node)
11683 if (TREE_CODE (f) == TYPE_DECL)
11685 complain |= tf_ignore_bad_quals;
11689 if (TREE_CODE (f) != TYPENAME_TYPE)
11691 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11693 if (complain & tf_error)
11694 error ("%qT resolves to %qT, which is not an enumeration type",
11697 return error_mark_node;
11699 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11701 if (complain & tf_error)
11702 error ("%qT resolves to %qT, which is is not a class type",
11705 return error_mark_node;
11709 return cp_build_qualified_type_real
11710 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11713 case UNBOUND_CLASS_TEMPLATE:
11715 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11716 in_decl, /*entering_scope=*/1);
11717 tree name = TYPE_IDENTIFIER (t);
11718 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11720 if (ctx == error_mark_node || name == error_mark_node)
11721 return error_mark_node;
11724 parm_list = tsubst_template_parms (parm_list, args, complain);
11725 return make_unbound_class_template (ctx, name, parm_list, complain);
11732 ++cp_unevaluated_operand;
11733 ++c_inhibit_evaluation_warnings;
11735 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11737 /*integral_constant_expression_p=*/false);
11739 --cp_unevaluated_operand;
11740 --c_inhibit_evaluation_warnings;
11742 type = finish_typeof (type);
11743 return cp_build_qualified_type_real (type,
11745 | cp_type_quals (type),
11749 case DECLTYPE_TYPE:
11753 ++cp_unevaluated_operand;
11754 ++c_inhibit_evaluation_warnings;
11756 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11758 /*integral_constant_expression_p=*/false);
11760 --cp_unevaluated_operand;
11761 --c_inhibit_evaluation_warnings;
11763 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11764 type = lambda_capture_field_type (type);
11765 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11766 type = lambda_proxy_type (type);
11768 type = finish_decltype_type
11769 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11770 return cp_build_qualified_type_real (type,
11772 | cp_type_quals (type),
11776 case UNDERLYING_TYPE:
11778 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11779 complain, in_decl);
11780 return finish_underlying_type (type);
11783 case TYPE_ARGUMENT_PACK:
11784 case NONTYPE_ARGUMENT_PACK:
11786 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11788 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11792 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11794 /* For template nontype argument packs, also substitute into
11796 if (code == NONTYPE_ARGUMENT_PACK)
11797 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11815 /* We should use one of the expression tsubsts for these codes. */
11816 gcc_unreachable ();
11819 sorry ("use of %qs in template", tree_code_name [(int) code]);
11820 return error_mark_node;
11824 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11825 type of the expression on the left-hand side of the "." or "->"
11829 tsubst_baselink (tree baselink, tree object_type,
11830 tree args, tsubst_flags_t complain, tree in_decl)
11833 tree qualifying_scope;
11836 tree template_args = 0;
11837 bool template_id_p = false;
11839 /* A baselink indicates a function from a base class. Both the
11840 BASELINK_ACCESS_BINFO and the base class referenced may
11841 indicate bases of the template class, rather than the
11842 instantiated class. In addition, lookups that were not
11843 ambiguous before may be ambiguous now. Therefore, we perform
11844 the lookup again. */
11845 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11846 qualifying_scope = tsubst (qualifying_scope, args,
11847 complain, in_decl);
11848 fns = BASELINK_FUNCTIONS (baselink);
11849 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11850 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11852 template_id_p = true;
11853 template_args = TREE_OPERAND (fns, 1);
11854 fns = TREE_OPERAND (fns, 0);
11856 template_args = tsubst_template_args (template_args, args,
11857 complain, in_decl);
11859 name = DECL_NAME (get_first_fn (fns));
11860 if (IDENTIFIER_TYPENAME_P (name))
11861 name = mangle_conv_op_name_for_type (optype);
11862 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11864 return error_mark_node;
11866 /* If lookup found a single function, mark it as used at this
11867 point. (If it lookup found multiple functions the one selected
11868 later by overload resolution will be marked as used at that
11870 if (BASELINK_P (baselink))
11871 fns = BASELINK_FUNCTIONS (baselink);
11872 if (!template_id_p && !really_overloaded_fn (fns))
11873 mark_used (OVL_CURRENT (fns));
11875 /* Add back the template arguments, if present. */
11876 if (BASELINK_P (baselink) && template_id_p)
11877 BASELINK_FUNCTIONS (baselink)
11878 = build_nt (TEMPLATE_ID_EXPR,
11879 BASELINK_FUNCTIONS (baselink),
11881 /* Update the conversion operator type. */
11882 BASELINK_OPTYPE (baselink) = optype;
11885 object_type = current_class_type;
11886 return adjust_result_of_qualified_name_lookup (baselink,
11891 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11892 true if the qualified-id will be a postfix-expression in-and-of
11893 itself; false if more of the postfix-expression follows the
11894 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11898 tsubst_qualified_id (tree qualified_id, tree args,
11899 tsubst_flags_t complain, tree in_decl,
11900 bool done, bool address_p)
11906 tree template_args;
11908 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11910 /* Figure out what name to look up. */
11911 name = TREE_OPERAND (qualified_id, 1);
11912 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11914 is_template = true;
11915 template_args = TREE_OPERAND (name, 1);
11917 template_args = tsubst_template_args (template_args, args,
11918 complain, in_decl);
11919 name = TREE_OPERAND (name, 0);
11923 is_template = false;
11924 template_args = NULL_TREE;
11927 /* Substitute into the qualifying scope. When there are no ARGS, we
11928 are just trying to simplify a non-dependent expression. In that
11929 case the qualifying scope may be dependent, and, in any case,
11930 substituting will not help. */
11931 scope = TREE_OPERAND (qualified_id, 0);
11934 scope = tsubst (scope, args, complain, in_decl);
11935 expr = tsubst_copy (name, args, complain, in_decl);
11940 if (dependent_scope_p (scope))
11943 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11944 return build_qualified_name (NULL_TREE, scope, expr,
11945 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11948 if (!BASELINK_P (name) && !DECL_P (expr))
11950 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11952 /* A BIT_NOT_EXPR is used to represent a destructor. */
11953 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11955 error ("qualifying type %qT does not match destructor name ~%qT",
11956 scope, TREE_OPERAND (expr, 0));
11957 expr = error_mark_node;
11960 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11961 /*is_type_p=*/0, false);
11964 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11965 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11966 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11968 if (complain & tf_error)
11970 error ("dependent-name %qE is parsed as a non-type, but "
11971 "instantiation yields a type", qualified_id);
11972 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11974 return error_mark_node;
11980 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11982 /* Remember that there was a reference to this entity. */
11986 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11988 if (complain & tf_error)
11989 qualified_name_lookup_error (scope,
11990 TREE_OPERAND (qualified_id, 1),
11991 expr, input_location);
11992 return error_mark_node;
11996 expr = lookup_template_function (expr, template_args);
11998 if (expr == error_mark_node && complain & tf_error)
11999 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12000 expr, input_location);
12001 else if (TYPE_P (scope))
12003 expr = (adjust_result_of_qualified_name_lookup
12004 (expr, scope, current_class_type));
12005 expr = (finish_qualified_id_expr
12006 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12007 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12008 /*template_arg_p=*/false));
12011 /* Expressions do not generally have reference type. */
12012 if (TREE_CODE (expr) != SCOPE_REF
12013 /* However, if we're about to form a pointer-to-member, we just
12014 want the referenced member referenced. */
12015 && TREE_CODE (expr) != OFFSET_REF)
12016 expr = convert_from_reference (expr);
12021 /* Like tsubst, but deals with expressions. This function just replaces
12022 template parms; to finish processing the resultant expression, use
12023 tsubst_copy_and_build or tsubst_expr. */
12026 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12028 enum tree_code code;
12031 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12034 code = TREE_CODE (t);
12039 r = retrieve_local_specialization (t);
12045 /* We get here for a use of 'this' in an NSDMI. */
12046 if (DECL_NAME (t) == this_identifier
12047 && at_function_scope_p ()
12048 && DECL_CONSTRUCTOR_P (current_function_decl))
12049 return current_class_ptr;
12051 /* This can happen for a parameter name used later in a function
12052 declaration (such as in a late-specified return type). Just
12053 make a dummy decl, since it's only used for its type. */
12054 gcc_assert (cp_unevaluated_operand != 0);
12055 /* We copy T because want to tsubst the PARM_DECL only,
12056 not the following PARM_DECLs that are chained to T. */
12058 r = tsubst_decl (c, args, complain);
12059 /* Give it the template pattern as its context; its true context
12060 hasn't been instantiated yet and this is good enough for
12062 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12065 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12066 r = ARGUMENT_PACK_SELECT_ARG (r);
12075 if (DECL_TEMPLATE_PARM_P (t))
12076 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12077 /* There is no need to substitute into namespace-scope
12079 if (DECL_NAMESPACE_SCOPE_P (t))
12081 /* If ARGS is NULL, then T is known to be non-dependent. */
12082 if (args == NULL_TREE)
12083 return integral_constant_value (t);
12085 /* Unfortunately, we cannot just call lookup_name here.
12088 template <int I> int f() {
12090 struct S { void g() { E e = a; } };
12093 When we instantiate f<7>::S::g(), say, lookup_name is not
12094 clever enough to find f<7>::a. */
12096 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12097 /*entering_scope=*/0);
12099 for (v = TYPE_VALUES (enum_type);
12101 v = TREE_CHAIN (v))
12102 if (TREE_PURPOSE (v) == DECL_NAME (t))
12103 return TREE_VALUE (v);
12105 /* We didn't find the name. That should never happen; if
12106 name-lookup found it during preliminary parsing, we
12107 should find it again here during instantiation. */
12108 gcc_unreachable ();
12113 if (DECL_CONTEXT (t))
12117 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12118 /*entering_scope=*/1);
12119 if (ctx != DECL_CONTEXT (t))
12121 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12124 if (complain & tf_error)
12125 error ("using invalid field %qD", t);
12126 return error_mark_node;
12135 case FUNCTION_DECL:
12136 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12137 || local_variable_p (t))
12138 t = tsubst (t, args, complain, in_decl);
12142 case NAMESPACE_DECL:
12146 /* An OVERLOAD will always be a non-dependent overload set; an
12147 overload set from function scope will just be represented with an
12148 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12149 gcc_assert (!uses_template_parms (t));
12153 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12155 case TEMPLATE_DECL:
12156 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12157 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12158 args, complain, in_decl);
12159 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12160 return tsubst (t, args, complain, in_decl);
12161 else if (DECL_CLASS_SCOPE_P (t)
12162 && uses_template_parms (DECL_CONTEXT (t)))
12164 /* Template template argument like the following example need
12167 template <template <class> class TT> struct C {};
12168 template <class T> struct D {
12169 template <class U> struct E {};
12174 We are processing the template argument `E' in #1 for
12175 the template instantiation #2. Originally, `E' is a
12176 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12177 have to substitute this with one having context `D<int>'. */
12179 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12180 return lookup_field (context, DECL_NAME(t), 0, false);
12183 /* Ordinary template template argument. */
12187 case REINTERPRET_CAST_EXPR:
12188 case CONST_CAST_EXPR:
12189 case STATIC_CAST_EXPR:
12190 case DYNAMIC_CAST_EXPR:
12191 case IMPLICIT_CONV_EXPR:
12195 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12196 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12199 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12205 ++cp_unevaluated_operand;
12206 ++c_inhibit_evaluation_warnings;
12207 /* We only want to compute the number of arguments. */
12208 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12209 complain, in_decl);
12210 --cp_unevaluated_operand;
12211 --c_inhibit_evaluation_warnings;
12213 if (TREE_CODE (expanded) == TREE_VEC)
12214 len = TREE_VEC_LENGTH (expanded);
12216 if (expanded == error_mark_node)
12217 return error_mark_node;
12218 else if (PACK_EXPANSION_P (expanded)
12219 || (TREE_CODE (expanded) == TREE_VEC
12221 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12223 if (TREE_CODE (expanded) == TREE_VEC)
12224 expanded = TREE_VEC_ELT (expanded, len - 1);
12226 if (TYPE_P (expanded))
12227 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12228 complain & tf_error);
12230 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12231 complain & tf_error);
12234 return build_int_cst (size_type_node, len);
12240 case TRUTH_NOT_EXPR:
12243 case UNARY_PLUS_EXPR: /* Unary + */
12245 case AT_ENCODE_EXPR:
12249 case REALPART_EXPR:
12250 case IMAGPART_EXPR:
12252 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12253 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12255 case COMPONENT_REF:
12260 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12261 name = TREE_OPERAND (t, 1);
12262 if (TREE_CODE (name) == BIT_NOT_EXPR)
12264 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12265 complain, in_decl);
12266 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12268 else if (TREE_CODE (name) == SCOPE_REF
12269 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12271 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12272 complain, in_decl);
12273 name = TREE_OPERAND (name, 1);
12274 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12275 complain, in_decl);
12276 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12277 name = build_qualified_name (/*type=*/NULL_TREE,
12279 /*template_p=*/false);
12281 else if (BASELINK_P (name))
12282 name = tsubst_baselink (name,
12283 non_reference (TREE_TYPE (object)),
12287 name = tsubst_copy (name, args, complain, in_decl);
12288 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12294 case TRUNC_DIV_EXPR:
12295 case CEIL_DIV_EXPR:
12296 case FLOOR_DIV_EXPR:
12297 case ROUND_DIV_EXPR:
12298 case EXACT_DIV_EXPR:
12302 case TRUNC_MOD_EXPR:
12303 case FLOOR_MOD_EXPR:
12304 case TRUTH_ANDIF_EXPR:
12305 case TRUTH_ORIF_EXPR:
12306 case TRUTH_AND_EXPR:
12307 case TRUTH_OR_EXPR:
12320 case COMPOUND_EXPR:
12323 case PREDECREMENT_EXPR:
12324 case PREINCREMENT_EXPR:
12325 case POSTDECREMENT_EXPR:
12326 case POSTINCREMENT_EXPR:
12328 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12329 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12332 return build_qualified_name (/*type=*/NULL_TREE,
12333 tsubst_copy (TREE_OPERAND (t, 0),
12334 args, complain, in_decl),
12335 tsubst_copy (TREE_OPERAND (t, 1),
12336 args, complain, in_decl),
12337 QUALIFIED_NAME_IS_TEMPLATE (t));
12342 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12343 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12344 NULL_TREE, NULL_TREE);
12348 int n = VL_EXP_OPERAND_LENGTH (t);
12349 tree result = build_vl_exp (CALL_EXPR, n);
12351 for (i = 0; i < n; i++)
12352 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12353 complain, in_decl);
12359 case PSEUDO_DTOR_EXPR:
12362 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12363 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12364 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12365 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12372 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12373 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12374 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12375 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12382 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12383 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12384 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12385 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12389 case TEMPLATE_ID_EXPR:
12391 /* Substituted template arguments */
12392 tree fn = TREE_OPERAND (t, 0);
12393 tree targs = TREE_OPERAND (t, 1);
12395 fn = tsubst_copy (fn, args, complain, in_decl);
12397 targs = tsubst_template_args (targs, args, complain, in_decl);
12399 return lookup_template_function (fn, targs);
12404 tree purpose, value, chain;
12406 if (t == void_list_node)
12409 purpose = TREE_PURPOSE (t);
12411 purpose = tsubst_copy (purpose, args, complain, in_decl);
12412 value = TREE_VALUE (t);
12414 value = tsubst_copy (value, args, complain, in_decl);
12415 chain = TREE_CHAIN (t);
12416 if (chain && chain != void_type_node)
12417 chain = tsubst_copy (chain, args, complain, in_decl);
12418 if (purpose == TREE_PURPOSE (t)
12419 && value == TREE_VALUE (t)
12420 && chain == TREE_CHAIN (t))
12422 return tree_cons (purpose, value, chain);
12427 case ENUMERAL_TYPE:
12429 case TEMPLATE_TYPE_PARM:
12430 case TEMPLATE_TEMPLATE_PARM:
12431 case BOUND_TEMPLATE_TEMPLATE_PARM:
12432 case TEMPLATE_PARM_INDEX:
12434 case REFERENCE_TYPE:
12436 case FUNCTION_TYPE:
12439 case TYPENAME_TYPE:
12440 case UNBOUND_CLASS_TEMPLATE:
12442 case DECLTYPE_TYPE:
12444 return tsubst (t, args, complain, in_decl);
12446 case IDENTIFIER_NODE:
12447 if (IDENTIFIER_TYPENAME_P (t))
12449 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12450 return mangle_conv_op_name_for_type (new_type);
12456 /* This is handled by tsubst_copy_and_build. */
12457 gcc_unreachable ();
12460 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12462 tsubst (TREE_TYPE (t), args, complain, in_decl));
12464 case CLEANUP_POINT_EXPR:
12465 /* We shouldn't have built any of these during initial template
12466 generation. Instead, they should be built during instantiation
12467 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12468 gcc_unreachable ();
12472 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12473 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12474 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12475 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12476 mark_used (TREE_OPERAND (r, 1));
12479 case EXPR_PACK_EXPANSION:
12480 error ("invalid use of pack expansion expression");
12481 return error_mark_node;
12483 case NONTYPE_ARGUMENT_PACK:
12484 error ("use %<...%> to expand argument pack");
12485 return error_mark_node;
12492 /* Instantiate any typedefs in the type. */
12493 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12494 r = fold_convert (type, t);
12495 gcc_assert (TREE_CODE (r) == code);
12500 /* These can sometimes show up in a partial instantiation, but never
12501 involve template parms. */
12502 gcc_assert (!uses_template_parms (t));
12506 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12507 gcc_checking_assert (false);
12512 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12515 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12518 tree new_clauses = NULL, nc, oc;
12520 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12522 nc = copy_node (oc);
12523 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12526 switch (OMP_CLAUSE_CODE (nc))
12528 case OMP_CLAUSE_LASTPRIVATE:
12529 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12531 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12532 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12533 in_decl, /*integral_constant_expression_p=*/false);
12534 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12535 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12538 case OMP_CLAUSE_PRIVATE:
12539 case OMP_CLAUSE_SHARED:
12540 case OMP_CLAUSE_FIRSTPRIVATE:
12541 case OMP_CLAUSE_REDUCTION:
12542 case OMP_CLAUSE_COPYIN:
12543 case OMP_CLAUSE_COPYPRIVATE:
12544 case OMP_CLAUSE_IF:
12545 case OMP_CLAUSE_NUM_THREADS:
12546 case OMP_CLAUSE_SCHEDULE:
12547 case OMP_CLAUSE_COLLAPSE:
12548 case OMP_CLAUSE_FINAL:
12549 OMP_CLAUSE_OPERAND (nc, 0)
12550 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12551 in_decl, /*integral_constant_expression_p=*/false);
12553 case OMP_CLAUSE_NOWAIT:
12554 case OMP_CLAUSE_ORDERED:
12555 case OMP_CLAUSE_DEFAULT:
12556 case OMP_CLAUSE_UNTIED:
12557 case OMP_CLAUSE_MERGEABLE:
12560 gcc_unreachable ();
12564 return finish_omp_clauses (nreverse (new_clauses));
12567 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12570 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12573 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12575 tree purpose, value, chain;
12580 if (TREE_CODE (t) != TREE_LIST)
12581 return tsubst_copy_and_build (t, args, complain, in_decl,
12582 /*function_p=*/false,
12583 /*integral_constant_expression_p=*/false);
12585 if (t == void_list_node)
12588 purpose = TREE_PURPOSE (t);
12590 purpose = RECUR (purpose);
12591 value = TREE_VALUE (t);
12592 if (value && TREE_CODE (value) != LABEL_DECL)
12593 value = RECUR (value);
12594 chain = TREE_CHAIN (t);
12595 if (chain && chain != void_type_node)
12596 chain = RECUR (chain);
12597 return tree_cons (purpose, value, chain);
12601 /* Substitute one OMP_FOR iterator. */
12604 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12605 tree condv, tree incrv, tree *clauses,
12606 tree args, tsubst_flags_t complain, tree in_decl,
12607 bool integral_constant_expression_p)
12609 #define RECUR(NODE) \
12610 tsubst_expr ((NODE), args, complain, in_decl, \
12611 integral_constant_expression_p)
12612 tree decl, init, cond, incr, auto_node;
12614 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12615 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12616 decl = RECUR (TREE_OPERAND (init, 0));
12617 init = TREE_OPERAND (init, 1);
12618 auto_node = type_uses_auto (TREE_TYPE (decl));
12619 if (auto_node && init)
12621 tree init_expr = init;
12622 if (TREE_CODE (init_expr) == DECL_EXPR)
12623 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12624 init_expr = RECUR (init_expr);
12626 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12628 gcc_assert (!type_dependent_expression_p (decl));
12630 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12632 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12633 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12634 if (TREE_CODE (incr) == MODIFY_EXPR)
12635 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12636 RECUR (TREE_OPERAND (incr, 1)),
12639 incr = RECUR (incr);
12640 TREE_VEC_ELT (declv, i) = decl;
12641 TREE_VEC_ELT (initv, i) = init;
12642 TREE_VEC_ELT (condv, i) = cond;
12643 TREE_VEC_ELT (incrv, i) = incr;
12647 if (init && TREE_CODE (init) != DECL_EXPR)
12650 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12652 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12653 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12654 && OMP_CLAUSE_DECL (c) == decl)
12656 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12657 && OMP_CLAUSE_DECL (c) == decl)
12658 error ("iteration variable %qD should not be firstprivate", decl);
12659 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12660 && OMP_CLAUSE_DECL (c) == decl)
12661 error ("iteration variable %qD should not be reduction", decl);
12665 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12666 OMP_CLAUSE_DECL (c) = decl;
12667 c = finish_omp_clauses (c);
12670 OMP_CLAUSE_CHAIN (c) = *clauses;
12675 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12676 if (COMPARISON_CLASS_P (cond))
12677 cond = build2 (TREE_CODE (cond), boolean_type_node,
12678 RECUR (TREE_OPERAND (cond, 0)),
12679 RECUR (TREE_OPERAND (cond, 1)));
12681 cond = RECUR (cond);
12682 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12683 switch (TREE_CODE (incr))
12685 case PREINCREMENT_EXPR:
12686 case PREDECREMENT_EXPR:
12687 case POSTINCREMENT_EXPR:
12688 case POSTDECREMENT_EXPR:
12689 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12690 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12693 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12694 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12696 tree rhs = TREE_OPERAND (incr, 1);
12697 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12698 RECUR (TREE_OPERAND (incr, 0)),
12699 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12700 RECUR (TREE_OPERAND (rhs, 0)),
12701 RECUR (TREE_OPERAND (rhs, 1))));
12704 incr = RECUR (incr);
12707 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12708 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12710 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12711 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12712 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12713 TREE_TYPE (decl), lhs,
12714 RECUR (TREE_OPERAND (incr, 2))));
12716 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12717 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12718 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12720 tree rhs = TREE_OPERAND (incr, 2);
12721 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12722 RECUR (TREE_OPERAND (incr, 0)),
12723 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12724 RECUR (TREE_OPERAND (rhs, 0)),
12725 RECUR (TREE_OPERAND (rhs, 1))));
12728 incr = RECUR (incr);
12731 incr = RECUR (incr);
12735 TREE_VEC_ELT (declv, i) = decl;
12736 TREE_VEC_ELT (initv, i) = init;
12737 TREE_VEC_ELT (condv, i) = cond;
12738 TREE_VEC_ELT (incrv, i) = incr;
12742 /* Like tsubst_copy for expressions, etc. but also does semantic
12746 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12747 bool integral_constant_expression_p)
12749 #define RECUR(NODE) \
12750 tsubst_expr ((NODE), args, complain, in_decl, \
12751 integral_constant_expression_p)
12755 if (t == NULL_TREE || t == error_mark_node)
12758 if (EXPR_HAS_LOCATION (t))
12759 input_location = EXPR_LOCATION (t);
12760 if (STATEMENT_CODE_P (TREE_CODE (t)))
12761 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12763 switch (TREE_CODE (t))
12765 case STATEMENT_LIST:
12767 tree_stmt_iterator i;
12768 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12769 RECUR (tsi_stmt (i));
12773 case CTOR_INITIALIZER:
12774 finish_mem_initializers (tsubst_initializer_list
12775 (TREE_OPERAND (t, 0), args));
12779 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12783 tmp = RECUR (EXPR_STMT_EXPR (t));
12784 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12785 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12787 finish_expr_stmt (tmp);
12791 do_using_directive (USING_STMT_NAMESPACE (t));
12796 tree decl, pattern_decl;
12799 pattern_decl = decl = DECL_EXPR_DECL (t);
12800 if (TREE_CODE (decl) == LABEL_DECL)
12801 finish_label_decl (DECL_NAME (decl));
12802 else if (TREE_CODE (decl) == USING_DECL)
12804 tree scope = USING_DECL_SCOPE (decl);
12805 tree name = DECL_NAME (decl);
12808 scope = tsubst (scope, args, complain, in_decl);
12809 decl = lookup_qualified_name (scope, name,
12810 /*is_type_p=*/false,
12811 /*complain=*/false);
12812 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12813 qualified_name_lookup_error (scope, name, decl, input_location);
12815 do_local_using_decl (decl, scope, name);
12819 init = DECL_INITIAL (decl);
12820 decl = tsubst (decl, args, complain, in_decl);
12821 if (decl != error_mark_node)
12823 /* By marking the declaration as instantiated, we avoid
12824 trying to instantiate it. Since instantiate_decl can't
12825 handle local variables, and since we've already done
12826 all that needs to be done, that's the right thing to
12828 if (TREE_CODE (decl) == VAR_DECL)
12829 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12830 if (TREE_CODE (decl) == VAR_DECL
12831 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12832 /* Anonymous aggregates are a special case. */
12833 finish_anon_union (decl);
12834 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12836 DECL_CONTEXT (decl) = current_function_decl;
12837 insert_capture_proxy (decl);
12841 int const_init = false;
12842 maybe_push_decl (decl);
12843 if (TREE_CODE (decl) == VAR_DECL
12844 && DECL_PRETTY_FUNCTION_P (decl))
12846 /* For __PRETTY_FUNCTION__ we have to adjust the
12848 const char *const name
12849 = cxx_printable_name (current_function_decl, 2);
12850 init = cp_fname_init (name, &TREE_TYPE (decl));
12854 tree t = RECUR (init);
12858 /* If we had an initializer but it
12859 instantiated to nothing,
12860 value-initialize the object. This will
12861 only occur when the initializer was a
12862 pack expansion where the parameter packs
12863 used in that expansion were of length
12865 init = build_value_init (TREE_TYPE (decl),
12867 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12868 init = get_target_expr_sfinae (init, complain);
12874 if (TREE_CODE (decl) == VAR_DECL)
12875 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12877 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12882 /* A DECL_EXPR can also be used as an expression, in the condition
12883 clause of an if/for/while construct. */
12888 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12889 RECUR (FOR_INIT_STMT (t));
12890 finish_for_init_stmt (stmt);
12891 tmp = RECUR (FOR_COND (t));
12892 finish_for_cond (tmp, stmt);
12893 tmp = RECUR (FOR_EXPR (t));
12894 finish_for_expr (tmp, stmt);
12895 RECUR (FOR_BODY (t));
12896 finish_for_stmt (stmt);
12899 case RANGE_FOR_STMT:
12902 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12903 decl = RANGE_FOR_DECL (t);
12904 decl = tsubst (decl, args, complain, in_decl);
12905 maybe_push_decl (decl);
12906 expr = RECUR (RANGE_FOR_EXPR (t));
12907 stmt = cp_convert_range_for (stmt, decl, expr);
12908 RECUR (RANGE_FOR_BODY (t));
12909 finish_for_stmt (stmt);
12914 stmt = begin_while_stmt ();
12915 tmp = RECUR (WHILE_COND (t));
12916 finish_while_stmt_cond (tmp, stmt);
12917 RECUR (WHILE_BODY (t));
12918 finish_while_stmt (stmt);
12922 stmt = begin_do_stmt ();
12923 RECUR (DO_BODY (t));
12924 finish_do_body (stmt);
12925 tmp = RECUR (DO_COND (t));
12926 finish_do_stmt (tmp, stmt);
12930 stmt = begin_if_stmt ();
12931 tmp = RECUR (IF_COND (t));
12932 finish_if_stmt_cond (tmp, stmt);
12933 RECUR (THEN_CLAUSE (t));
12934 finish_then_clause (stmt);
12936 if (ELSE_CLAUSE (t))
12938 begin_else_clause (stmt);
12939 RECUR (ELSE_CLAUSE (t));
12940 finish_else_clause (stmt);
12943 finish_if_stmt (stmt);
12947 if (BIND_EXPR_BODY_BLOCK (t))
12948 stmt = begin_function_body ();
12950 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12951 ? BCS_TRY_BLOCK : 0);
12953 RECUR (BIND_EXPR_BODY (t));
12955 if (BIND_EXPR_BODY_BLOCK (t))
12956 finish_function_body (stmt);
12958 finish_compound_stmt (stmt);
12962 finish_break_stmt ();
12965 case CONTINUE_STMT:
12966 finish_continue_stmt ();
12970 stmt = begin_switch_stmt ();
12971 tmp = RECUR (SWITCH_STMT_COND (t));
12972 finish_switch_cond (tmp, stmt);
12973 RECUR (SWITCH_STMT_BODY (t));
12974 finish_switch_stmt (stmt);
12977 case CASE_LABEL_EXPR:
12978 finish_case_label (EXPR_LOCATION (t),
12979 RECUR (CASE_LOW (t)),
12980 RECUR (CASE_HIGH (t)));
12985 tree decl = LABEL_EXPR_LABEL (t);
12988 label = finish_label_stmt (DECL_NAME (decl));
12989 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12990 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12995 tmp = GOTO_DESTINATION (t);
12996 if (TREE_CODE (tmp) != LABEL_DECL)
12997 /* Computed goto's must be tsubst'd into. On the other hand,
12998 non-computed gotos must not be; the identifier in question
12999 will have no binding. */
13002 tmp = DECL_NAME (tmp);
13003 finish_goto_stmt (tmp);
13007 tmp = finish_asm_stmt
13008 (ASM_VOLATILE_P (t),
13009 RECUR (ASM_STRING (t)),
13010 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13011 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13012 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13013 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13015 tree asm_expr = tmp;
13016 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13017 asm_expr = TREE_OPERAND (asm_expr, 0);
13018 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13025 stmt = begin_try_block ();
13026 RECUR (TRY_STMTS (t));
13027 finish_cleanup_try_block (stmt);
13028 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13032 tree compound_stmt = NULL_TREE;
13034 if (FN_TRY_BLOCK_P (t))
13035 stmt = begin_function_try_block (&compound_stmt);
13037 stmt = begin_try_block ();
13039 RECUR (TRY_STMTS (t));
13041 if (FN_TRY_BLOCK_P (t))
13042 finish_function_try_block (stmt);
13044 finish_try_block (stmt);
13046 RECUR (TRY_HANDLERS (t));
13047 if (FN_TRY_BLOCK_P (t))
13048 finish_function_handler_sequence (stmt, compound_stmt);
13050 finish_handler_sequence (stmt);
13056 tree decl = HANDLER_PARMS (t);
13060 decl = tsubst (decl, args, complain, in_decl);
13061 /* Prevent instantiate_decl from trying to instantiate
13062 this variable. We've already done all that needs to be
13064 if (decl != error_mark_node)
13065 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13067 stmt = begin_handler ();
13068 finish_handler_parms (decl, stmt);
13069 RECUR (HANDLER_BODY (t));
13070 finish_handler (stmt);
13075 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13078 case STATIC_ASSERT:
13081 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13084 /*integral_constant_expression_p=*/true);
13085 finish_static_assert (condition,
13086 STATIC_ASSERT_MESSAGE (t),
13087 STATIC_ASSERT_SOURCE_LOCATION (t),
13088 /*member_p=*/false);
13093 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13094 args, complain, in_decl);
13095 stmt = begin_omp_parallel ();
13096 RECUR (OMP_PARALLEL_BODY (t));
13097 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13098 = OMP_PARALLEL_COMBINED (t);
13102 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13103 args, complain, in_decl);
13104 stmt = begin_omp_task ();
13105 RECUR (OMP_TASK_BODY (t));
13106 finish_omp_task (tmp, stmt);
13111 tree clauses, body, pre_body;
13112 tree declv, initv, condv, incrv;
13115 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13116 args, complain, in_decl);
13117 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13118 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13119 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13120 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13122 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13123 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13124 &clauses, args, complain, in_decl,
13125 integral_constant_expression_p);
13127 stmt = begin_omp_structured_block ();
13129 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13130 if (TREE_VEC_ELT (initv, i) == NULL
13131 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13132 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13133 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13135 tree init = RECUR (TREE_VEC_ELT (initv, i));
13136 gcc_assert (init == TREE_VEC_ELT (declv, i));
13137 TREE_VEC_ELT (initv, i) = NULL_TREE;
13141 tree decl_expr = TREE_VEC_ELT (initv, i);
13142 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13143 gcc_assert (init != NULL);
13144 TREE_VEC_ELT (initv, i) = RECUR (init);
13145 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13147 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13150 pre_body = push_stmt_list ();
13151 RECUR (OMP_FOR_PRE_BODY (t));
13152 pre_body = pop_stmt_list (pre_body);
13154 body = push_stmt_list ();
13155 RECUR (OMP_FOR_BODY (t));
13156 body = pop_stmt_list (body);
13158 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13159 body, pre_body, clauses);
13161 add_stmt (finish_omp_structured_block (stmt));
13167 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13168 stmt = push_stmt_list ();
13169 RECUR (OMP_BODY (t));
13170 stmt = pop_stmt_list (stmt);
13173 OMP_BODY (t) = stmt;
13174 OMP_CLAUSES (t) = tmp;
13182 stmt = push_stmt_list ();
13183 RECUR (OMP_BODY (t));
13184 stmt = pop_stmt_list (stmt);
13187 OMP_BODY (t) = stmt;
13192 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13193 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13195 tree op1 = TREE_OPERAND (t, 1);
13196 tree rhs1 = NULL_TREE;
13198 if (TREE_CODE (op1) == COMPOUND_EXPR)
13200 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13201 op1 = TREE_OPERAND (op1, 1);
13203 lhs = RECUR (TREE_OPERAND (op1, 0));
13204 rhs = RECUR (TREE_OPERAND (op1, 1));
13205 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13206 NULL_TREE, NULL_TREE, rhs1);
13210 tree op1 = TREE_OPERAND (t, 1);
13211 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13212 tree rhs1 = NULL_TREE;
13213 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13214 enum tree_code opcode = NOP_EXPR;
13215 if (code == OMP_ATOMIC_READ)
13217 v = RECUR (TREE_OPERAND (op1, 0));
13218 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13220 else if (code == OMP_ATOMIC_CAPTURE_OLD
13221 || code == OMP_ATOMIC_CAPTURE_NEW)
13223 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13224 v = RECUR (TREE_OPERAND (op1, 0));
13225 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13226 if (TREE_CODE (op11) == COMPOUND_EXPR)
13228 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13229 op11 = TREE_OPERAND (op11, 1);
13231 lhs = RECUR (TREE_OPERAND (op11, 0));
13232 rhs = RECUR (TREE_OPERAND (op11, 1));
13233 opcode = TREE_CODE (op11);
13238 lhs = RECUR (TREE_OPERAND (op1, 0));
13239 rhs = RECUR (TREE_OPERAND (op1, 1));
13241 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13245 case TRANSACTION_EXPR:
13248 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13249 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13251 if (TRANSACTION_EXPR_IS_STMT (t))
13253 tree body = TRANSACTION_EXPR_BODY (t);
13254 tree noex = NULL_TREE;
13255 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13257 noex = MUST_NOT_THROW_COND (body);
13258 if (noex == NULL_TREE)
13259 noex = boolean_true_node;
13260 body = TREE_OPERAND (body, 0);
13262 stmt = begin_transaction_stmt (input_location, NULL, flags);
13264 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13268 stmt = build_transaction_expr (EXPR_LOCATION (t),
13269 RECUR (TRANSACTION_EXPR_BODY (t)),
13276 case MUST_NOT_THROW_EXPR:
13277 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13278 RECUR (MUST_NOT_THROW_COND (t)));
13280 case EXPR_PACK_EXPANSION:
13281 error ("invalid use of pack expansion expression");
13282 return error_mark_node;
13284 case NONTYPE_ARGUMENT_PACK:
13285 error ("use %<...%> to expand argument pack");
13286 return error_mark_node;
13289 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13291 return tsubst_copy_and_build (t, args, complain, in_decl,
13292 /*function_p=*/false,
13293 integral_constant_expression_p);
13300 /* T is a postfix-expression that is not being used in a function
13301 call. Return the substituted version of T. */
13304 tsubst_non_call_postfix_expression (tree t, tree args,
13305 tsubst_flags_t complain,
13308 if (TREE_CODE (t) == SCOPE_REF)
13309 t = tsubst_qualified_id (t, args, complain, in_decl,
13310 /*done=*/false, /*address_p=*/false);
13312 t = tsubst_copy_and_build (t, args, complain, in_decl,
13313 /*function_p=*/false,
13314 /*integral_constant_expression_p=*/false);
13319 /* Like tsubst but deals with expressions and performs semantic
13320 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13323 tsubst_copy_and_build (tree t,
13325 tsubst_flags_t complain,
13328 bool integral_constant_expression_p)
13330 #define RECUR(NODE) \
13331 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13332 /*function_p=*/false, \
13333 integral_constant_expression_p)
13337 if (t == NULL_TREE || t == error_mark_node)
13340 switch (TREE_CODE (t))
13344 /* Fall through. */
13345 case IDENTIFIER_NODE:
13349 bool non_integral_constant_expression_p;
13350 const char *error_msg;
13352 if (IDENTIFIER_TYPENAME_P (t))
13354 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13355 t = mangle_conv_op_name_for_type (new_type);
13358 /* Look up the name. */
13359 decl = lookup_name (t);
13361 /* By convention, expressions use ERROR_MARK_NODE to indicate
13362 failure, not NULL_TREE. */
13363 if (decl == NULL_TREE)
13364 decl = error_mark_node;
13366 decl = finish_id_expression (t, decl, NULL_TREE,
13368 integral_constant_expression_p,
13369 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13370 &non_integral_constant_expression_p,
13371 /*template_p=*/false,
13373 /*address_p=*/false,
13374 /*template_arg_p=*/false,
13379 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13381 if (complain & tf_error)
13382 unqualified_name_lookup_error (decl);
13383 decl = error_mark_node;
13388 case TEMPLATE_ID_EXPR:
13391 tree templ = RECUR (TREE_OPERAND (t, 0));
13392 tree targs = TREE_OPERAND (t, 1);
13395 targs = tsubst_template_args (targs, args, complain, in_decl);
13397 if (TREE_CODE (templ) == COMPONENT_REF)
13399 object = TREE_OPERAND (templ, 0);
13400 templ = TREE_OPERAND (templ, 1);
13403 object = NULL_TREE;
13404 templ = lookup_template_function (templ, targs);
13407 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13408 object, templ, NULL_TREE);
13410 return baselink_for_fns (templ);
13415 tree r = RECUR (TREE_OPERAND (t, 0));
13417 if (REFERENCE_REF_P (t))
13419 /* A type conversion to reference type will be enclosed in
13420 such an indirect ref, but the substitution of the cast
13421 will have also added such an indirect ref. */
13422 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13423 r = convert_from_reference (r);
13426 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13432 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13433 RECUR (TREE_OPERAND (t, 0)));
13435 case IMPLICIT_CONV_EXPR:
13437 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13438 tree expr = RECUR (TREE_OPERAND (t, 0));
13439 int flags = LOOKUP_IMPLICIT;
13440 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13441 flags = LOOKUP_NORMAL;
13442 return perform_implicit_conversion_flags (type, expr, complain,
13449 tsubst (TREE_TYPE (t), args, complain, in_decl),
13450 RECUR (TREE_OPERAND (t, 0)));
13453 case REINTERPRET_CAST_EXPR:
13454 case CONST_CAST_EXPR:
13455 case DYNAMIC_CAST_EXPR:
13456 case STATIC_CAST_EXPR:
13461 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13462 if (integral_constant_expression_p
13463 && !cast_valid_in_integral_constant_expression_p (type))
13465 if (complain & tf_error)
13466 error ("a cast to a type other than an integral or "
13467 "enumeration type cannot appear in a constant-expression");
13468 return error_mark_node;
13471 op = RECUR (TREE_OPERAND (t, 0));
13473 switch (TREE_CODE (t))
13476 return build_functional_cast (type, op, complain);
13477 case REINTERPRET_CAST_EXPR:
13478 return build_reinterpret_cast (type, op, complain);
13479 case CONST_CAST_EXPR:
13480 return build_const_cast (type, op, complain);
13481 case DYNAMIC_CAST_EXPR:
13482 return build_dynamic_cast (type, op, complain);
13483 case STATIC_CAST_EXPR:
13484 return build_static_cast (type, op, complain);
13486 gcc_unreachable ();
13490 case POSTDECREMENT_EXPR:
13491 case POSTINCREMENT_EXPR:
13492 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13493 args, complain, in_decl);
13494 return build_x_unary_op (TREE_CODE (t), op1, complain);
13496 case PREDECREMENT_EXPR:
13497 case PREINCREMENT_EXPR:
13501 case TRUTH_NOT_EXPR:
13502 case UNARY_PLUS_EXPR: /* Unary + */
13503 case REALPART_EXPR:
13504 case IMAGPART_EXPR:
13505 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13508 case FIX_TRUNC_EXPR:
13509 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13513 op1 = TREE_OPERAND (t, 0);
13514 if (TREE_CODE (op1) == LABEL_DECL)
13515 return finish_label_address_expr (DECL_NAME (op1),
13516 EXPR_LOCATION (op1));
13517 if (TREE_CODE (op1) == SCOPE_REF)
13518 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13519 /*done=*/true, /*address_p=*/true);
13521 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13523 return build_x_unary_op (ADDR_EXPR, op1, complain);
13528 case TRUNC_DIV_EXPR:
13529 case CEIL_DIV_EXPR:
13530 case FLOOR_DIV_EXPR:
13531 case ROUND_DIV_EXPR:
13532 case EXACT_DIV_EXPR:
13536 case TRUNC_MOD_EXPR:
13537 case FLOOR_MOD_EXPR:
13538 case TRUTH_ANDIF_EXPR:
13539 case TRUTH_ORIF_EXPR:
13540 case TRUTH_AND_EXPR:
13541 case TRUTH_OR_EXPR:
13556 return build_x_binary_op
13558 RECUR (TREE_OPERAND (t, 0)),
13559 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13561 : TREE_CODE (TREE_OPERAND (t, 0))),
13562 RECUR (TREE_OPERAND (t, 1)),
13563 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13565 : TREE_CODE (TREE_OPERAND (t, 1))),
13570 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13571 /*address_p=*/false);
13573 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13574 args, complain, in_decl);
13575 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13578 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13579 return tsubst_copy (t, args, complain, in_decl);
13583 op1 = TREE_OPERAND (t, 0);
13586 /* When there are no ARGS, we are trying to evaluate a
13587 non-dependent expression from the parser. Trying to do
13588 the substitutions may not work. */
13590 op1 = TREE_TYPE (op1);
13594 ++cp_unevaluated_operand;
13595 ++c_inhibit_evaluation_warnings;
13596 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13597 /*function_p=*/false,
13598 /*integral_constant_expression_p=*/false);
13599 --cp_unevaluated_operand;
13600 --c_inhibit_evaluation_warnings;
13603 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13604 complain & tf_error);
13606 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13607 complain & tf_error);
13609 case AT_ENCODE_EXPR:
13611 op1 = TREE_OPERAND (t, 0);
13612 ++cp_unevaluated_operand;
13613 ++c_inhibit_evaluation_warnings;
13614 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13615 /*function_p=*/false,
13616 /*integral_constant_expression_p=*/false);
13617 --cp_unevaluated_operand;
13618 --c_inhibit_evaluation_warnings;
13619 return objc_build_encode_expr (op1);
13622 case NOEXCEPT_EXPR:
13623 op1 = TREE_OPERAND (t, 0);
13624 ++cp_unevaluated_operand;
13625 ++c_inhibit_evaluation_warnings;
13626 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13627 /*function_p=*/false,
13628 /*integral_constant_expression_p=*/false);
13629 --cp_unevaluated_operand;
13630 --c_inhibit_evaluation_warnings;
13631 return finish_noexcept_expr (op1, complain);
13635 tree r = build_x_modify_expr
13636 (RECUR (TREE_OPERAND (t, 0)),
13637 TREE_CODE (TREE_OPERAND (t, 1)),
13638 RECUR (TREE_OPERAND (t, 2)),
13640 /* TREE_NO_WARNING must be set if either the expression was
13641 parenthesized or it uses an operator such as >>= rather
13642 than plain assignment. In the former case, it was already
13643 set and must be copied. In the latter case,
13644 build_x_modify_expr sets it and it must not be reset
13646 if (TREE_NO_WARNING (t))
13647 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13652 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13653 args, complain, in_decl);
13654 /* Remember that there was a reference to this entity. */
13657 return build_x_arrow (op1);
13661 tree placement = RECUR (TREE_OPERAND (t, 0));
13662 tree init = RECUR (TREE_OPERAND (t, 3));
13663 VEC(tree,gc) *placement_vec;
13664 VEC(tree,gc) *init_vec;
13667 if (placement == NULL_TREE)
13668 placement_vec = NULL;
13671 placement_vec = make_tree_vector ();
13672 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13673 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13676 /* If there was an initializer in the original tree, but it
13677 instantiated to an empty list, then we should pass a
13678 non-NULL empty vector to tell build_new that it was an
13679 empty initializer() rather than no initializer. This can
13680 only happen when the initializer is a pack expansion whose
13681 parameter packs are of length zero. */
13682 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13686 init_vec = make_tree_vector ();
13687 if (init == void_zero_node)
13688 gcc_assert (init_vec != NULL);
13691 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13692 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13696 ret = build_new (&placement_vec,
13697 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13698 RECUR (TREE_OPERAND (t, 2)),
13700 NEW_EXPR_USE_GLOBAL (t),
13703 if (placement_vec != NULL)
13704 release_tree_vector (placement_vec);
13705 if (init_vec != NULL)
13706 release_tree_vector (init_vec);
13712 return delete_sanity
13713 (RECUR (TREE_OPERAND (t, 0)),
13714 RECUR (TREE_OPERAND (t, 1)),
13715 DELETE_EXPR_USE_VEC (t),
13716 DELETE_EXPR_USE_GLOBAL (t),
13719 case COMPOUND_EXPR:
13720 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13721 RECUR (TREE_OPERAND (t, 1)),
13727 VEC(tree,gc) *call_args;
13728 unsigned int nargs, i;
13733 function = CALL_EXPR_FN (t);
13734 /* When we parsed the expression, we determined whether or
13735 not Koenig lookup should be performed. */
13736 koenig_p = KOENIG_LOOKUP_P (t);
13737 if (TREE_CODE (function) == SCOPE_REF)
13739 qualified_p = true;
13740 function = tsubst_qualified_id (function, args, complain, in_decl,
13742 /*address_p=*/false);
13744 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13746 /* Do nothing; calling tsubst_copy_and_build on an identifier
13747 would incorrectly perform unqualified lookup again.
13749 Note that we can also have an IDENTIFIER_NODE if the earlier
13750 unqualified lookup found a member function; in that case
13751 koenig_p will be false and we do want to do the lookup
13752 again to find the instantiated member function.
13754 FIXME but doing that causes c++/15272, so we need to stop
13755 using IDENTIFIER_NODE in that situation. */
13756 qualified_p = false;
13760 if (TREE_CODE (function) == COMPONENT_REF)
13762 tree op = TREE_OPERAND (function, 1);
13764 qualified_p = (TREE_CODE (op) == SCOPE_REF
13765 || (BASELINK_P (op)
13766 && BASELINK_QUALIFIED_P (op)));
13769 qualified_p = false;
13771 function = tsubst_copy_and_build (function, args, complain,
13774 integral_constant_expression_p);
13776 if (BASELINK_P (function))
13777 qualified_p = true;
13780 nargs = call_expr_nargs (t);
13781 call_args = make_tree_vector ();
13782 for (i = 0; i < nargs; ++i)
13784 tree arg = CALL_EXPR_ARG (t, i);
13786 if (!PACK_EXPANSION_P (arg))
13787 VEC_safe_push (tree, gc, call_args,
13788 RECUR (CALL_EXPR_ARG (t, i)));
13791 /* Expand the pack expansion and push each entry onto
13793 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13794 if (TREE_CODE (arg) == TREE_VEC)
13796 unsigned int len, j;
13798 len = TREE_VEC_LENGTH (arg);
13799 for (j = 0; j < len; ++j)
13801 tree value = TREE_VEC_ELT (arg, j);
13802 if (value != NULL_TREE)
13803 value = convert_from_reference (value);
13804 VEC_safe_push (tree, gc, call_args, value);
13809 /* A partial substitution. Add one entry. */
13810 VEC_safe_push (tree, gc, call_args, arg);
13815 /* We do not perform argument-dependent lookup if normal
13816 lookup finds a non-function, in accordance with the
13817 expected resolution of DR 218. */
13819 && ((is_overloaded_fn (function)
13820 /* If lookup found a member function, the Koenig lookup is
13821 not appropriate, even if an unqualified-name was used
13822 to denote the function. */
13823 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13824 || TREE_CODE (function) == IDENTIFIER_NODE)
13825 /* Only do this when substitution turns a dependent call
13826 into a non-dependent call. */
13827 && type_dependent_expression_p_push (t)
13828 && !any_type_dependent_arguments_p (call_args))
13829 function = perform_koenig_lookup (function, call_args, false,
13832 if (TREE_CODE (function) == IDENTIFIER_NODE
13833 && !any_type_dependent_arguments_p (call_args))
13835 if (koenig_p && (complain & tf_warning_or_error))
13837 /* For backwards compatibility and good diagnostics, try
13838 the unqualified lookup again if we aren't in SFINAE
13840 tree unq = (tsubst_copy_and_build
13841 (function, args, complain, in_decl, true,
13842 integral_constant_expression_p));
13843 if (unq == error_mark_node)
13844 return error_mark_node;
13846 if (unq != function)
13849 if (TREE_CODE (fn) == INDIRECT_REF)
13850 fn = TREE_OPERAND (fn, 0);
13851 if (TREE_CODE (fn) == COMPONENT_REF)
13852 fn = TREE_OPERAND (fn, 1);
13853 if (is_overloaded_fn (fn))
13854 fn = get_first_fn (fn);
13855 permerror (EXPR_LOC_OR_HERE (t),
13856 "%qD was not declared in this scope, "
13857 "and no declarations were found by "
13858 "argument-dependent lookup at the point "
13859 "of instantiation", function);
13861 /* Can't say anything more. */;
13862 else if (DECL_CLASS_SCOPE_P (fn))
13864 inform (EXPR_LOC_OR_HERE (t),
13865 "declarations in dependent base %qT are "
13866 "not found by unqualified lookup",
13867 DECL_CLASS_CONTEXT (fn));
13868 if (current_class_ptr)
13869 inform (EXPR_LOC_OR_HERE (t),
13870 "use %<this->%D%> instead", function);
13872 inform (EXPR_LOC_OR_HERE (t),
13873 "use %<%T::%D%> instead",
13874 current_class_name, function);
13877 inform (0, "%q+D declared here, later in the "
13878 "translation unit", fn);
13882 if (TREE_CODE (function) == IDENTIFIER_NODE)
13884 unqualified_name_lookup_error (function);
13885 release_tree_vector (call_args);
13886 return error_mark_node;
13890 /* Remember that there was a reference to this entity. */
13891 if (DECL_P (function))
13892 mark_used (function);
13894 if (TREE_CODE (function) == OFFSET_REF)
13895 ret = build_offset_ref_call_from_tree (function, &call_args);
13896 else if (TREE_CODE (function) == COMPONENT_REF)
13898 tree instance = TREE_OPERAND (function, 0);
13899 tree fn = TREE_OPERAND (function, 1);
13901 if (processing_template_decl
13902 && (type_dependent_expression_p (instance)
13903 || (!BASELINK_P (fn)
13904 && TREE_CODE (fn) != FIELD_DECL)
13905 || type_dependent_expression_p (fn)
13906 || any_type_dependent_arguments_p (call_args)))
13907 ret = build_nt_call_vec (function, call_args);
13908 else if (!BASELINK_P (fn))
13909 ret = finish_call_expr (function, &call_args,
13910 /*disallow_virtual=*/false,
13911 /*koenig_p=*/false,
13914 ret = (build_new_method_call
13916 &call_args, NULL_TREE,
13917 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13922 ret = finish_call_expr (function, &call_args,
13923 /*disallow_virtual=*/qualified_p,
13927 release_tree_vector (call_args);
13933 return build_x_conditional_expr
13934 (RECUR (TREE_OPERAND (t, 0)),
13935 RECUR (TREE_OPERAND (t, 1)),
13936 RECUR (TREE_OPERAND (t, 2)),
13939 case PSEUDO_DTOR_EXPR:
13940 return finish_pseudo_destructor_expr
13941 (RECUR (TREE_OPERAND (t, 0)),
13942 RECUR (TREE_OPERAND (t, 1)),
13943 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13947 tree purpose, value, chain;
13949 if (t == void_list_node)
13952 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13953 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13955 /* We have pack expansions, so expand those and
13956 create a new list out of it. */
13957 tree purposevec = NULL_TREE;
13958 tree valuevec = NULL_TREE;
13962 /* Expand the argument expressions. */
13963 if (TREE_PURPOSE (t))
13964 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13965 complain, in_decl);
13966 if (TREE_VALUE (t))
13967 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13968 complain, in_decl);
13970 /* Build the rest of the list. */
13971 chain = TREE_CHAIN (t);
13972 if (chain && chain != void_type_node)
13973 chain = RECUR (chain);
13975 /* Determine the number of arguments. */
13976 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13978 len = TREE_VEC_LENGTH (purposevec);
13979 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13981 else if (TREE_CODE (valuevec) == TREE_VEC)
13982 len = TREE_VEC_LENGTH (valuevec);
13985 /* Since we only performed a partial substitution into
13986 the argument pack, we only return a single list
13988 if (purposevec == TREE_PURPOSE (t)
13989 && valuevec == TREE_VALUE (t)
13990 && chain == TREE_CHAIN (t))
13993 return tree_cons (purposevec, valuevec, chain);
13996 /* Convert the argument vectors into a TREE_LIST */
14000 /* Grab the Ith values. */
14002 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14005 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14008 /* Build the list (backwards). */
14009 chain = tree_cons (purpose, value, chain);
14015 purpose = TREE_PURPOSE (t);
14017 purpose = RECUR (purpose);
14018 value = TREE_VALUE (t);
14020 value = RECUR (value);
14021 chain = TREE_CHAIN (t);
14022 if (chain && chain != void_type_node)
14023 chain = RECUR (chain);
14024 if (purpose == TREE_PURPOSE (t)
14025 && value == TREE_VALUE (t)
14026 && chain == TREE_CHAIN (t))
14028 return tree_cons (purpose, value, chain);
14031 case COMPONENT_REF:
14037 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14038 args, complain, in_decl);
14039 /* Remember that there was a reference to this entity. */
14040 if (DECL_P (object))
14041 mark_used (object);
14042 object_type = TREE_TYPE (object);
14044 member = TREE_OPERAND (t, 1);
14045 if (BASELINK_P (member))
14046 member = tsubst_baselink (member,
14047 non_reference (TREE_TYPE (object)),
14048 args, complain, in_decl);
14050 member = tsubst_copy (member, args, complain, in_decl);
14051 if (member == error_mark_node)
14052 return error_mark_node;
14054 if (type_dependent_expression_p (object))
14055 /* We can't do much here. */;
14056 else if (!CLASS_TYPE_P (object_type))
14058 if (SCALAR_TYPE_P (object_type))
14060 tree s = NULL_TREE;
14061 tree dtor = member;
14063 if (TREE_CODE (dtor) == SCOPE_REF)
14065 s = TREE_OPERAND (dtor, 0);
14066 dtor = TREE_OPERAND (dtor, 1);
14068 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14070 dtor = TREE_OPERAND (dtor, 0);
14072 return finish_pseudo_destructor_expr (object, s, dtor);
14076 else if (TREE_CODE (member) == SCOPE_REF
14077 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14079 /* Lookup the template functions now that we know what the
14081 tree scope = TREE_OPERAND (member, 0);
14082 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14083 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14084 member = lookup_qualified_name (scope, tmpl,
14085 /*is_type_p=*/false,
14086 /*complain=*/false);
14087 if (BASELINK_P (member))
14089 BASELINK_FUNCTIONS (member)
14090 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14092 member = (adjust_result_of_qualified_name_lookup
14093 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14098 qualified_name_lookup_error (scope, tmpl, member,
14100 return error_mark_node;
14103 else if (TREE_CODE (member) == SCOPE_REF
14104 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14105 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14107 if (complain & tf_error)
14109 if (TYPE_P (TREE_OPERAND (member, 0)))
14110 error ("%qT is not a class or namespace",
14111 TREE_OPERAND (member, 0));
14113 error ("%qD is not a class or namespace",
14114 TREE_OPERAND (member, 0));
14116 return error_mark_node;
14118 else if (TREE_CODE (member) == FIELD_DECL)
14119 return finish_non_static_data_member (member, object, NULL_TREE);
14121 return finish_class_member_access_expr (object, member,
14122 /*template_p=*/false,
14128 (RECUR (TREE_OPERAND (t, 0)));
14132 VEC(constructor_elt,gc) *n;
14133 constructor_elt *ce;
14134 unsigned HOST_WIDE_INT idx;
14135 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14136 bool process_index_p;
14138 bool need_copy_p = false;
14141 if (type == error_mark_node)
14142 return error_mark_node;
14144 /* digest_init will do the wrong thing if we let it. */
14145 if (type && TYPE_PTRMEMFUNC_P (type))
14148 /* We do not want to process the index of aggregate
14149 initializers as they are identifier nodes which will be
14150 looked up by digest_init. */
14151 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14153 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14154 newlen = VEC_length (constructor_elt, n);
14155 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14157 if (ce->index && process_index_p)
14158 ce->index = RECUR (ce->index);
14160 if (PACK_EXPANSION_P (ce->value))
14162 /* Substitute into the pack expansion. */
14163 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14166 if (ce->value == error_mark_node
14167 || PACK_EXPANSION_P (ce->value))
14169 else if (TREE_VEC_LENGTH (ce->value) == 1)
14170 /* Just move the argument into place. */
14171 ce->value = TREE_VEC_ELT (ce->value, 0);
14174 /* Update the length of the final CONSTRUCTOR
14175 arguments vector, and note that we will need to
14177 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14178 need_copy_p = true;
14182 ce->value = RECUR (ce->value);
14187 VEC(constructor_elt,gc) *old_n = n;
14189 n = VEC_alloc (constructor_elt, gc, newlen);
14190 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14192 if (TREE_CODE (ce->value) == TREE_VEC)
14194 int i, len = TREE_VEC_LENGTH (ce->value);
14195 for (i = 0; i < len; ++i)
14196 CONSTRUCTOR_APPEND_ELT (n, 0,
14197 TREE_VEC_ELT (ce->value, i));
14200 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14204 r = build_constructor (init_list_type_node, n);
14205 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14207 if (TREE_HAS_CONSTRUCTOR (t))
14208 return finish_compound_literal (type, r, complain);
14210 TREE_TYPE (r) = type;
14216 tree operand_0 = TREE_OPERAND (t, 0);
14217 if (TYPE_P (operand_0))
14219 operand_0 = tsubst (operand_0, args, complain, in_decl);
14220 return get_typeid (operand_0);
14224 operand_0 = RECUR (operand_0);
14225 return build_typeid (operand_0);
14236 tree r = tsubst_copy (t, args, complain, in_decl);
14238 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14239 /* If the original type was a reference, we'll be wrapped in
14240 the appropriate INDIRECT_REF. */
14241 r = convert_from_reference (r);
14246 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14247 tsubst (TREE_TYPE (t), args, complain, in_decl));
14249 case OFFSETOF_EXPR:
14250 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14254 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14255 complain, in_decl);
14257 tree type2 = TRAIT_EXPR_TYPE2 (t);
14259 type2 = tsubst_copy (type2, args, complain, in_decl);
14261 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14266 tree old_stmt_expr = cur_stmt_expr;
14267 tree stmt_expr = begin_stmt_expr ();
14269 cur_stmt_expr = stmt_expr;
14270 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14271 integral_constant_expression_p);
14272 stmt_expr = finish_stmt_expr (stmt_expr, false);
14273 cur_stmt_expr = old_stmt_expr;
14275 /* If the resulting list of expression statement is empty,
14276 fold it further into void_zero_node. */
14277 if (empty_expr_stmt_p (stmt_expr))
14278 stmt_expr = void_zero_node;
14284 t = tsubst_copy (t, args, complain, in_decl);
14285 /* As in finish_id_expression, we resolve enumeration constants
14286 to their underlying values. */
14287 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14289 used_types_insert (TREE_TYPE (t));
14290 return DECL_INITIAL (t);
14296 tree r = build_lambda_expr ();
14298 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14299 LAMBDA_EXPR_CLOSURE (r) = type;
14300 CLASSTYPE_LAMBDA_EXPR (type) = r;
14302 LAMBDA_EXPR_LOCATION (r)
14303 = LAMBDA_EXPR_LOCATION (t);
14304 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14305 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14306 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14307 LAMBDA_EXPR_DISCRIMINATOR (r)
14308 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14309 LAMBDA_EXPR_EXTRA_SCOPE (r)
14310 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14311 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14313 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14314 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14317 LAMBDA_EXPR_RETURN_TYPE (r)
14318 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14320 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14321 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14323 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14324 determine_visibility (TYPE_NAME (type));
14325 /* Now that we know visibility, instantiate the type so we have a
14326 declaration of the op() for later calls to lambda_function. */
14327 complete_type (type);
14329 /* The capture list refers to closure members, so this needs to
14330 wait until after we finish instantiating the type. */
14331 LAMBDA_EXPR_CAPTURE_LIST (r)
14332 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14334 return build_lambda_object (r);
14338 /* We can get here for a constant initializer of non-dependent type.
14339 FIXME stop folding in cp_parser_initializer_clause. */
14340 gcc_assert (TREE_CONSTANT (t));
14342 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14343 TREE_CONSTANT (r) = true;
14347 case TRANSACTION_EXPR:
14348 return tsubst_expr(t, args, complain, in_decl,
14349 integral_constant_expression_p);
14352 /* Handle Objective-C++ constructs, if appropriate. */
14355 = objcp_tsubst_copy_and_build (t, args, complain,
14356 in_decl, /*function_p=*/false);
14360 return tsubst_copy (t, args, complain, in_decl);
14366 /* Verify that the instantiated ARGS are valid. For type arguments,
14367 make sure that the type's linkage is ok. For non-type arguments,
14368 make sure they are constants if they are integral or enumerations.
14369 Emit an error under control of COMPLAIN, and return TRUE on error. */
14372 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14374 if (ARGUMENT_PACK_P (t))
14376 tree vec = ARGUMENT_PACK_ARGS (t);
14377 int len = TREE_VEC_LENGTH (vec);
14378 bool result = false;
14381 for (i = 0; i < len; ++i)
14382 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14386 else if (TYPE_P (t))
14388 /* [basic.link]: A name with no linkage (notably, the name
14389 of a class or enumeration declared in a local scope)
14390 shall not be used to declare an entity with linkage.
14391 This implies that names with no linkage cannot be used as
14394 DR 757 relaxes this restriction for C++0x. */
14395 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14396 : no_linkage_check (t, /*relaxed_p=*/false));
14400 /* DR 488 makes use of a type with no linkage cause
14401 type deduction to fail. */
14402 if (complain & tf_error)
14404 if (TYPE_ANONYMOUS_P (nt))
14405 error ("%qT is/uses anonymous type", t);
14407 error ("template argument for %qD uses local type %qT",
14412 /* In order to avoid all sorts of complications, we do not
14413 allow variably-modified types as template arguments. */
14414 else if (variably_modified_type_p (t, NULL_TREE))
14416 if (complain & tf_error)
14417 error ("%qT is a variably modified type", t);
14421 /* A non-type argument of integral or enumerated type must be a
14423 else if (TREE_TYPE (t)
14424 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14425 && !TREE_CONSTANT (t))
14427 if (complain & tf_error)
14428 error ("integral expression %qE is not constant", t);
14435 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14437 int ix, len = DECL_NTPARMS (tmpl);
14438 bool result = false;
14440 for (ix = 0; ix != len; ix++)
14442 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14445 if (result && (complain & tf_error))
14446 error (" trying to instantiate %qD", tmpl);
14450 /* In C++0x, it's possible to have a function template whose type depends
14451 on itself recursively. This is most obvious with decltype, but can also
14452 occur with enumeration scope (c++/48969). So we need to catch infinite
14453 recursion and reject the substitution at deduction time; this function
14454 will return error_mark_node for any repeated substitution.
14456 This also catches excessive recursion such as when f<N> depends on
14457 f<N-1> across all integers, and returns error_mark_node for all the
14458 substitutions back up to the initial one.
14460 This is, of course, not reentrant. */
14463 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14465 static bool excessive_deduction_depth;
14466 static int deduction_depth;
14467 struct pending_template *old_last_pend = last_pending_template;
14468 struct tinst_level *old_error_tinst = last_error_tinst_level;
14470 tree fntype = TREE_TYPE (fn);
14474 if (excessive_deduction_depth)
14475 return error_mark_node;
14477 tinst = build_tree_list (fn, targs);
14478 if (!push_tinst_level (tinst))
14480 excessive_deduction_depth = true;
14482 return error_mark_node;
14485 input_location = DECL_SOURCE_LOCATION (fn);
14487 push_deduction_access_scope (fn);
14488 r = tsubst (fntype, targs, complain, NULL_TREE);
14489 pop_deduction_access_scope (fn);
14492 if (excessive_deduction_depth)
14494 r = error_mark_node;
14495 if (deduction_depth == 0)
14496 /* Reset once we're all the way out. */
14497 excessive_deduction_depth = false;
14500 pop_tinst_level ();
14501 /* We can't free this if a pending_template entry or last_error_tinst_level
14502 is pointing at it. */
14503 if (last_pending_template == old_last_pend
14504 && last_error_tinst_level == old_error_tinst)
14509 /* Instantiate the indicated variable or function template TMPL with
14510 the template arguments in TARG_PTR. */
14513 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14515 tree targ_ptr = orig_args;
14519 HOST_WIDE_INT saved_processing_template_decl;
14521 if (tmpl == error_mark_node)
14522 return error_mark_node;
14524 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14526 /* If this function is a clone, handle it specially. */
14527 if (DECL_CLONED_FUNCTION_P (tmpl))
14532 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14533 DECL_CLONED_FUNCTION. */
14534 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14535 targ_ptr, complain);
14536 if (spec == error_mark_node)
14537 return error_mark_node;
14539 /* Look for the clone. */
14540 FOR_EACH_CLONE (clone, spec)
14541 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14543 /* We should always have found the clone by now. */
14544 gcc_unreachable ();
14548 /* Check to see if we already have this specialization. */
14549 gen_tmpl = most_general_template (tmpl);
14550 if (tmpl != gen_tmpl)
14551 /* The TMPL is a partial instantiation. To get a full set of
14552 arguments we must add the arguments used to perform the
14553 partial instantiation. */
14554 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14557 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14558 but it doesn't seem to be on the hot path. */
14559 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14561 gcc_assert (tmpl == gen_tmpl
14562 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14564 || fndecl == NULL_TREE);
14566 if (spec != NULL_TREE)
14569 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14571 return error_mark_node;
14573 /* We are building a FUNCTION_DECL, during which the access of its
14574 parameters and return types have to be checked. However this
14575 FUNCTION_DECL which is the desired context for access checking
14576 is not built yet. We solve this chicken-and-egg problem by
14577 deferring all checks until we have the FUNCTION_DECL. */
14578 push_deferring_access_checks (dk_deferred);
14580 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
14581 (because, for example, we have encountered a non-dependent
14582 function call in the body of a template function and must now
14583 determine which of several overloaded functions will be called),
14584 within the instantiation itself we are not processing a
14586 saved_processing_template_decl = processing_template_decl;
14587 processing_template_decl = 0;
14588 /* Substitute template parameters to obtain the specialization. */
14589 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14590 targ_ptr, complain, gen_tmpl);
14591 processing_template_decl = saved_processing_template_decl;
14592 if (fndecl == error_mark_node)
14593 return error_mark_node;
14595 /* Now we know the specialization, compute access previously
14597 push_access_scope (fndecl);
14599 /* Some typedefs referenced from within the template code need to be access
14600 checked at template instantiation time, i.e now. These types were
14601 added to the template at parsing time. Let's get those and perfom
14602 the acces checks then. */
14603 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14604 perform_deferred_access_checks ();
14605 pop_access_scope (fndecl);
14606 pop_deferring_access_checks ();
14608 /* The DECL_TI_TEMPLATE should always be the immediate parent
14609 template, not the most general template. */
14610 DECL_TI_TEMPLATE (fndecl) = tmpl;
14612 /* If we've just instantiated the main entry point for a function,
14613 instantiate all the alternate entry points as well. We do this
14614 by cloning the instantiation of the main entry point, not by
14615 instantiating the template clones. */
14616 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14617 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14622 /* Wrapper for instantiate_template_1. */
14625 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14628 timevar_push (TV_TEMPLATE_INST);
14629 ret = instantiate_template_1 (tmpl, orig_args, complain);
14630 timevar_pop (TV_TEMPLATE_INST);
14634 /* We're going to do deduction substitution on the type of TMPL, a function
14635 template. In C++11 mode, push into that access scope. In C++03 mode,
14636 disable access checking. */
14639 push_deduction_access_scope (tree tmpl)
14641 if (cxx_dialect >= cxx0x)
14643 int ptd = processing_template_decl;
14644 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14645 /* Preserve processing_template_decl across push_to_top_level. */
14646 if (ptd && !processing_template_decl)
14647 ++processing_template_decl;
14650 push_deferring_access_checks (dk_no_check);
14653 /* And pop back out. */
14656 pop_deduction_access_scope (tree tmpl)
14658 if (cxx_dialect >= cxx0x)
14659 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14661 pop_deferring_access_checks ();
14664 /* PARM is a template parameter pack for FN. Returns true iff
14665 PARM is used in a deducible way in the argument list of FN. */
14668 pack_deducible_p (tree parm, tree fn)
14670 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14671 for (; t; t = TREE_CHAIN (t))
14673 tree type = TREE_VALUE (t);
14675 if (!PACK_EXPANSION_P (type))
14677 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14678 packs; packs = TREE_CHAIN (packs))
14679 if (TREE_VALUE (packs) == parm)
14681 /* The template parameter pack is used in a function parameter
14682 pack. If this is the end of the parameter list, the
14683 template parameter pack is deducible. */
14684 if (TREE_CHAIN (t) == void_list_node)
14687 /* Otherwise, not. Well, it could be deduced from
14688 a non-pack parameter, but doing so would end up with
14689 a deduction mismatch, so don't bother. */
14693 /* The template parameter pack isn't used in any function parameter
14694 packs, but it might be used deeper, e.g. tuple<Args...>. */
14698 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14699 NARGS elements of the arguments that are being used when calling
14700 it. TARGS is a vector into which the deduced template arguments
14703 Return zero for success, 2 for an incomplete match that doesn't resolve
14704 all the types, and 1 for complete failure. An error message will be
14705 printed only for an incomplete match.
14707 If FN is a conversion operator, or we are trying to produce a specific
14708 specialization, RETURN_TYPE is the return type desired.
14710 The EXPLICIT_TARGS are explicit template arguments provided via a
14713 The parameter STRICT is one of:
14716 We are deducing arguments for a function call, as in
14717 [temp.deduct.call].
14720 We are deducing arguments for a conversion function, as in
14721 [temp.deduct.conv].
14724 We are deducing arguments when doing an explicit instantiation
14725 as in [temp.explicit], when determining an explicit specialization
14726 as in [temp.expl.spec], or when taking the address of a function
14727 template, as in [temp.deduct.funcaddr]. */
14730 fn_type_unification (tree fn,
14731 tree explicit_targs,
14734 unsigned int nargs,
14736 unification_kind_t strict,
14744 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14746 fntype = TREE_TYPE (fn);
14747 if (explicit_targs)
14751 The specified template arguments must match the template
14752 parameters in kind (i.e., type, nontype, template), and there
14753 must not be more arguments than there are parameters;
14754 otherwise type deduction fails.
14756 Nontype arguments must match the types of the corresponding
14757 nontype template parameters, or must be convertible to the
14758 types of the corresponding nontype parameters as specified in
14759 _temp.arg.nontype_, otherwise type deduction fails.
14761 All references in the function type of the function template
14762 to the corresponding template parameters are replaced by the
14763 specified template argument values. If a substitution in a
14764 template parameter or in the function type of the function
14765 template results in an invalid type, type deduction fails. */
14766 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14767 int i, len = TREE_VEC_LENGTH (tparms);
14768 tree converted_args;
14769 bool incomplete = false;
14771 if (explicit_targs == error_mark_node)
14772 return unify_invalid (explain_p);
14775 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14777 ? tf_warning_or_error
14779 /*require_all_args=*/false,
14780 /*use_default_args=*/false));
14781 if (converted_args == error_mark_node)
14784 /* Substitute the explicit args into the function type. This is
14785 necessary so that, for instance, explicitly declared function
14786 arguments can match null pointed constants. If we were given
14787 an incomplete set of explicit args, we must not do semantic
14788 processing during substitution as we could create partial
14790 for (i = 0; i < len; i++)
14792 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14793 bool parameter_pack = false;
14794 tree targ = TREE_VEC_ELT (converted_args, i);
14796 /* Dig out the actual parm. */
14797 if (TREE_CODE (parm) == TYPE_DECL
14798 || TREE_CODE (parm) == TEMPLATE_DECL)
14800 parm = TREE_TYPE (parm);
14801 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14803 else if (TREE_CODE (parm) == PARM_DECL)
14805 parm = DECL_INITIAL (parm);
14806 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14809 if (!parameter_pack && targ == NULL_TREE)
14810 /* No explicit argument for this template parameter. */
14813 if (parameter_pack && pack_deducible_p (parm, fn))
14815 /* Mark the argument pack as "incomplete". We could
14816 still deduce more arguments during unification.
14817 We remove this mark in type_unification_real. */
14820 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14821 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14822 = ARGUMENT_PACK_ARGS (targ);
14825 /* We have some incomplete argument packs. */
14830 processing_template_decl += incomplete;
14831 fntype = deduction_tsubst_fntype (fn, converted_args,
14833 ? tf_warning_or_error
14835 processing_template_decl -= incomplete;
14837 if (fntype == error_mark_node)
14840 /* Place the explicitly specified arguments in TARGS. */
14841 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14842 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14845 /* Never do unification on the 'this' parameter. */
14846 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14852 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14853 new_args = XALLOCAVEC (tree, nargs + 1);
14854 new_args[0] = return_type;
14855 memcpy (new_args + 1, args, nargs * sizeof (tree));
14860 /* We allow incomplete unification without an error message here
14861 because the standard doesn't seem to explicitly prohibit it. Our
14862 callers must be ready to deal with unification failures in any
14864 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14865 targs, parms, args, nargs, /*subr=*/0,
14866 strict, flags, explain_p);
14868 /* Now that we have bindings for all of the template arguments,
14869 ensure that the arguments deduced for the template template
14870 parameters have compatible template parameter lists. We cannot
14871 check this property before we have deduced all template
14872 arguments, because the template parameter types of a template
14873 template parameter might depend on prior template parameters
14874 deduced after the template template parameter. The following
14875 ill-formed example illustrates this issue:
14877 template<typename T, template<T> class C> void f(C<5>, T);
14879 template<int N> struct X {};
14882 f(X<5>(), 5l); // error: template argument deduction fails
14885 The template parameter list of 'C' depends on the template type
14886 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14887 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14888 time that we deduce 'C'. */
14890 && !template_template_parm_bindings_ok_p
14891 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14892 return unify_inconsistent_template_template_parameters (explain_p);
14895 /* All is well so far. Now, check:
14899 When all template arguments have been deduced, all uses of
14900 template parameters in nondeduced contexts are replaced with
14901 the corresponding deduced argument values. If the
14902 substitution results in an invalid type, as described above,
14903 type deduction fails. */
14905 tree substed = deduction_tsubst_fntype (fn, targs,
14907 ? tf_warning_or_error
14909 if (substed == error_mark_node)
14912 /* If we're looking for an exact match, check that what we got
14913 is indeed an exact match. It might not be if some template
14914 parameters are used in non-deduced contexts. */
14915 if (strict == DEDUCE_EXACT)
14920 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14922 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14923 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14924 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14925 return unify_type_mismatch (explain_p, args[i],
14926 TREE_VALUE (sarg));
14933 /* Adjust types before performing type deduction, as described in
14934 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14935 sections are symmetric. PARM is the type of a function parameter
14936 or the return type of the conversion function. ARG is the type of
14937 the argument passed to the call, or the type of the value
14938 initialized with the result of the conversion function.
14939 ARG_EXPR is the original argument expression, which may be null. */
14942 maybe_adjust_types_for_deduction (unification_kind_t strict,
14956 /* Swap PARM and ARG throughout the remainder of this
14957 function; the handling is precisely symmetric since PARM
14958 will initialize ARG rather than vice versa. */
14966 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14967 too, but here handle it by stripping the reference from PARM
14968 rather than by adding it to ARG. */
14969 if (TREE_CODE (*parm) == REFERENCE_TYPE
14970 && TYPE_REF_IS_RVALUE (*parm)
14971 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14972 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14973 && TREE_CODE (*arg) == REFERENCE_TYPE
14974 && !TYPE_REF_IS_RVALUE (*arg))
14975 *parm = TREE_TYPE (*parm);
14976 /* Nothing else to do in this case. */
14980 gcc_unreachable ();
14983 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14985 /* [temp.deduct.call]
14987 If P is not a reference type:
14989 --If A is an array type, the pointer type produced by the
14990 array-to-pointer standard conversion (_conv.array_) is
14991 used in place of A for type deduction; otherwise,
14993 --If A is a function type, the pointer type produced by
14994 the function-to-pointer standard conversion
14995 (_conv.func_) is used in place of A for type deduction;
14998 --If A is a cv-qualified type, the top level
14999 cv-qualifiers of A's type are ignored for type
15001 if (TREE_CODE (*arg) == ARRAY_TYPE)
15002 *arg = build_pointer_type (TREE_TYPE (*arg));
15003 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15004 *arg = build_pointer_type (*arg);
15006 *arg = TYPE_MAIN_VARIANT (*arg);
15009 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15010 of the form T&&, where T is a template parameter, and the argument
15011 is an lvalue, T is deduced as A& */
15012 if (TREE_CODE (*parm) == REFERENCE_TYPE
15013 && TYPE_REF_IS_RVALUE (*parm)
15014 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15015 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15016 && (arg_expr ? real_lvalue_p (arg_expr)
15017 /* try_one_overload doesn't provide an arg_expr, but
15018 functions are always lvalues. */
15019 : TREE_CODE (*arg) == FUNCTION_TYPE))
15020 *arg = build_reference_type (*arg);
15022 /* [temp.deduct.call]
15024 If P is a cv-qualified type, the top level cv-qualifiers
15025 of P's type are ignored for type deduction. If P is a
15026 reference type, the type referred to by P is used for
15028 *parm = TYPE_MAIN_VARIANT (*parm);
15029 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15031 *parm = TREE_TYPE (*parm);
15032 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15035 /* DR 322. For conversion deduction, remove a reference type on parm
15036 too (which has been swapped into ARG). */
15037 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15038 *arg = TREE_TYPE (*arg);
15043 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15044 template which does contain any deducible template parameters; check if
15045 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15046 unify_one_argument. */
15049 check_non_deducible_conversion (tree parm, tree arg, int strict,
15050 int flags, bool explain_p)
15055 type = TREE_TYPE (arg);
15059 if (same_type_p (parm, type))
15060 return unify_success (explain_p);
15062 if (strict == DEDUCE_CONV)
15064 if (can_convert_arg (type, parm, NULL_TREE, flags))
15065 return unify_success (explain_p);
15067 else if (strict != DEDUCE_EXACT)
15069 if (can_convert_arg (parm, type,
15070 TYPE_P (arg) ? NULL_TREE : arg,
15072 return unify_success (explain_p);
15075 if (strict == DEDUCE_EXACT)
15076 return unify_type_mismatch (explain_p, parm, arg);
15078 return unify_arg_conversion (explain_p, parm, type, arg);
15081 /* Subroutine of type_unification_real and unify_pack_expansion to
15082 handle unification of a single P/A pair. Parameters are as
15083 for those functions. */
15086 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15087 int subr, unification_kind_t strict, int flags,
15090 tree arg_expr = NULL_TREE;
15093 if (arg == error_mark_node || parm == error_mark_node)
15094 return unify_invalid (explain_p);
15095 if (arg == unknown_type_node)
15096 /* We can't deduce anything from this, but we might get all the
15097 template args from other function args. */
15098 return unify_success (explain_p);
15100 /* FIXME uses_deducible_template_parms */
15101 if (TYPE_P (parm) && !uses_template_parms (parm))
15102 return check_non_deducible_conversion (parm, arg, strict, flags,
15108 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15109 | UNIFY_ALLOW_MORE_CV_QUAL
15110 | UNIFY_ALLOW_DERIVED);
15114 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15118 arg_strict = UNIFY_ALLOW_NONE;
15122 gcc_unreachable ();
15125 /* We only do these transformations if this is the top-level
15126 parameter_type_list in a call or declaration matching; in other
15127 situations (nested function declarators, template argument lists) we
15128 won't be comparing a type to an expression, and we don't do any type
15134 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15135 if (type_unknown_p (arg))
15137 /* [temp.deduct.type] A template-argument can be
15138 deduced from a pointer to function or pointer
15139 to member function argument if the set of
15140 overloaded functions does not contain function
15141 templates and at most one of a set of
15142 overloaded functions provides a unique
15145 if (resolve_overloaded_unification
15146 (tparms, targs, parm, arg, strict,
15147 arg_strict, explain_p))
15148 return unify_success (explain_p);
15149 return unify_overload_resolution_failure (explain_p, arg);
15153 arg = unlowered_expr_type (arg);
15154 if (arg == error_mark_node)
15155 return unify_invalid (explain_p);
15159 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15162 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15163 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15165 /* For deduction from an init-list we need the actual list. */
15166 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15168 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15171 /* Most parms like fn_type_unification.
15173 If SUBR is 1, we're being called recursively (to unify the
15174 arguments of a function or method parameter of a function
15178 type_unification_real (tree tparms,
15182 unsigned int xnargs,
15184 unification_kind_t strict,
15190 int ntparms = TREE_VEC_LENGTH (tparms);
15191 int saw_undeduced = 0;
15194 unsigned int nargs;
15197 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15198 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15199 gcc_assert (ntparms > 0);
15201 /* Reset the number of non-defaulted template arguments contained
15203 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15211 while (parms && parms != void_list_node
15214 parm = TREE_VALUE (parms);
15216 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15217 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15218 /* For a function parameter pack that occurs at the end of the
15219 parameter-declaration-list, the type A of each remaining
15220 argument of the call is compared with the type P of the
15221 declarator-id of the function parameter pack. */
15224 parms = TREE_CHAIN (parms);
15226 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15227 /* For a function parameter pack that does not occur at the
15228 end of the parameter-declaration-list, the type of the
15229 parameter pack is a non-deduced context. */
15235 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15241 && parms != void_list_node
15242 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15244 /* Unify the remaining arguments with the pack expansion type. */
15246 tree parmvec = make_tree_vec (1);
15248 /* Allocate a TREE_VEC and copy in all of the arguments */
15249 argvec = make_tree_vec (nargs - ia);
15250 for (i = 0; ia < nargs; ++ia, ++i)
15251 TREE_VEC_ELT (argvec, i) = args[ia];
15253 /* Copy the parameter into parmvec. */
15254 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15255 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15256 /*subr=*/subr, explain_p))
15259 /* Advance to the end of the list of parameters. */
15260 parms = TREE_CHAIN (parms);
15263 /* Fail if we've reached the end of the parm list, and more args
15264 are present, and the parm list isn't variadic. */
15265 if (ia < nargs && parms == void_list_node)
15266 return unify_too_many_arguments (explain_p, nargs, ia);
15267 /* Fail if parms are left and they don't have default values. */
15268 if (parms && parms != void_list_node
15269 && TREE_PURPOSE (parms) == NULL_TREE)
15271 unsigned int count = nargs;
15273 while (p && p != void_list_node)
15276 p = TREE_CHAIN (p);
15278 return unify_too_few_arguments (explain_p, ia, count);
15283 tsubst_flags_t complain = (explain_p
15284 ? tf_warning_or_error
15287 /* Check to see if we need another pass before we start clearing
15288 ARGUMENT_PACK_INCOMPLETE_P. */
15289 for (i = 0; i < ntparms; i++)
15291 tree targ = TREE_VEC_ELT (targs, i);
15292 tree tparm = TREE_VEC_ELT (tparms, i);
15294 if (targ || tparm == error_mark_node)
15296 tparm = TREE_VALUE (tparm);
15298 /* If this is an undeduced nontype parameter that depends on
15299 a type parameter, try another pass; its type may have been
15300 deduced from a later argument than the one from which
15301 this parameter can be deduced. */
15302 if (TREE_CODE (tparm) == PARM_DECL
15303 && uses_template_parms (TREE_TYPE (tparm))
15304 && !saw_undeduced++)
15308 for (i = 0; i < ntparms; i++)
15310 tree targ = TREE_VEC_ELT (targs, i);
15311 tree tparm = TREE_VEC_ELT (tparms, i);
15313 /* Clear the "incomplete" flags on all argument packs now so that
15314 substituting them into later default arguments works. */
15315 if (targ && ARGUMENT_PACK_P (targ))
15317 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15318 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15321 if (targ || tparm == error_mark_node)
15323 tparm = TREE_VALUE (tparm);
15325 /* Core issue #226 (C++0x) [temp.deduct]:
15327 If a template argument has not been deduced, its
15328 default template argument, if any, is used.
15330 When we are in C++98 mode, TREE_PURPOSE will either
15331 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15332 to explicitly check cxx_dialect here. */
15333 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15335 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15336 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15337 location_t save_loc = input_location;
15339 input_location = DECL_SOURCE_LOCATION (parm);
15340 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15341 arg = convert_template_argument (parm, arg, targs, complain,
15343 input_location = save_loc;
15344 if (arg == error_mark_node)
15348 TREE_VEC_ELT (targs, i) = arg;
15349 /* The position of the first default template argument,
15350 is also the number of non-defaulted arguments in TARGS.
15352 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15353 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15358 /* If the type parameter is a parameter pack, then it will
15359 be deduced to an empty parameter pack. */
15360 if (template_parameter_pack_p (tparm))
15364 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15366 arg = make_node (NONTYPE_ARGUMENT_PACK);
15367 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15368 TREE_CONSTANT (arg) = 1;
15371 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15373 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15375 TREE_VEC_ELT (targs, i) = arg;
15379 return unify_parameter_deduction_failure (explain_p, tparm);
15382 #ifdef ENABLE_CHECKING
15383 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15384 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15387 return unify_success (explain_p);
15390 /* Subroutine of type_unification_real. Args are like the variables
15391 at the call site. ARG is an overloaded function (or template-id);
15392 we try deducing template args from each of the overloads, and if
15393 only one succeeds, we go with that. Modifies TARGS and returns
15394 true on success. */
15397 resolve_overloaded_unification (tree tparms,
15401 unification_kind_t strict,
15405 tree tempargs = copy_node (targs);
15407 tree goodfn = NULL_TREE;
15410 if (TREE_CODE (arg) == ADDR_EXPR)
15412 arg = TREE_OPERAND (arg, 0);
15418 if (TREE_CODE (arg) == COMPONENT_REF)
15419 /* Handle `&x' where `x' is some static or non-static member
15421 arg = TREE_OPERAND (arg, 1);
15423 if (TREE_CODE (arg) == OFFSET_REF)
15424 arg = TREE_OPERAND (arg, 1);
15426 /* Strip baselink information. */
15427 if (BASELINK_P (arg))
15428 arg = BASELINK_FUNCTIONS (arg);
15430 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15432 /* If we got some explicit template args, we need to plug them into
15433 the affected templates before we try to unify, in case the
15434 explicit args will completely resolve the templates in question. */
15437 tree expl_subargs = TREE_OPERAND (arg, 1);
15438 arg = TREE_OPERAND (arg, 0);
15440 for (; arg; arg = OVL_NEXT (arg))
15442 tree fn = OVL_CURRENT (arg);
15443 tree subargs, elem;
15445 if (TREE_CODE (fn) != TEMPLATE_DECL)
15448 ++processing_template_decl;
15449 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15450 expl_subargs, /*check_ret=*/false);
15451 if (subargs && !any_dependent_template_arguments_p (subargs))
15453 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15454 if (try_one_overload (tparms, targs, tempargs, parm,
15455 elem, strict, sub_strict, addr_p, explain_p)
15456 && (!goodfn || !decls_match (goodfn, elem)))
15464 --processing_template_decl;
15466 /* If no templates (or more than one) are fully resolved by the
15467 explicit arguments, this template-id is a non-deduced context; it
15468 could still be OK if we deduce all template arguments for the
15469 enclosing call through other arguments. */
15473 else if (TREE_CODE (arg) != OVERLOAD
15474 && TREE_CODE (arg) != FUNCTION_DECL)
15475 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15476 -- but the deduction does not succeed because the expression is
15477 not just the function on its own. */
15480 for (; arg; arg = OVL_NEXT (arg))
15481 if (try_one_overload (tparms, targs, tempargs, parm,
15482 TREE_TYPE (OVL_CURRENT (arg)),
15483 strict, sub_strict, addr_p, explain_p)
15484 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15486 goodfn = OVL_CURRENT (arg);
15490 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15491 to function or pointer to member function argument if the set of
15492 overloaded functions does not contain function templates and at most
15493 one of a set of overloaded functions provides a unique match.
15495 So if we found multiple possibilities, we return success but don't
15496 deduce anything. */
15500 int i = TREE_VEC_LENGTH (targs);
15502 if (TREE_VEC_ELT (tempargs, i))
15503 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15511 /* Core DR 115: In contexts where deduction is done and fails, or in
15512 contexts where deduction is not done, if a template argument list is
15513 specified and it, along with any default template arguments, identifies
15514 a single function template specialization, then the template-id is an
15515 lvalue for the function template specialization. */
15518 resolve_nondeduced_context (tree orig_expr)
15520 tree expr, offset, baselink;
15523 if (!type_unknown_p (orig_expr))
15528 offset = NULL_TREE;
15529 baselink = NULL_TREE;
15531 if (TREE_CODE (expr) == ADDR_EXPR)
15533 expr = TREE_OPERAND (expr, 0);
15536 if (TREE_CODE (expr) == OFFSET_REF)
15539 expr = TREE_OPERAND (expr, 1);
15541 if (BASELINK_P (expr))
15544 expr = BASELINK_FUNCTIONS (expr);
15547 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15550 tree goodfn = NULL_TREE;
15552 /* If we got some explicit template args, we need to plug them into
15553 the affected templates before we try to unify, in case the
15554 explicit args will completely resolve the templates in question. */
15556 tree expl_subargs = TREE_OPERAND (expr, 1);
15557 tree arg = TREE_OPERAND (expr, 0);
15558 tree badfn = NULL_TREE;
15559 tree badargs = NULL_TREE;
15561 for (; arg; arg = OVL_NEXT (arg))
15563 tree fn = OVL_CURRENT (arg);
15564 tree subargs, elem;
15566 if (TREE_CODE (fn) != TEMPLATE_DECL)
15569 ++processing_template_decl;
15570 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15571 expl_subargs, /*check_ret=*/false);
15572 if (subargs && !any_dependent_template_arguments_p (subargs))
15574 elem = instantiate_template (fn, subargs, tf_none);
15575 if (elem == error_mark_node)
15580 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15586 --processing_template_decl;
15590 mark_used (goodfn);
15593 expr = build_baselink (BASELINK_BINFO (baselink),
15594 BASELINK_ACCESS_BINFO (baselink),
15595 expr, BASELINK_OPTYPE (baselink));
15599 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15600 expr = build_offset_ref (base, expr, addr);
15603 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15606 else if (good == 0 && badargs)
15607 /* There were no good options and at least one bad one, so let the
15608 user know what the problem is. */
15609 instantiate_template (badfn, badargs, tf_warning_or_error);
15614 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15615 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15616 different overloads deduce different arguments for a given parm.
15617 ADDR_P is true if the expression for which deduction is being
15618 performed was of the form "& fn" rather than simply "fn".
15620 Returns 1 on success. */
15623 try_one_overload (tree tparms,
15628 unification_kind_t strict,
15637 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15638 to function or pointer to member function argument if the set of
15639 overloaded functions does not contain function templates and at most
15640 one of a set of overloaded functions provides a unique match.
15642 So if this is a template, just return success. */
15644 if (uses_template_parms (arg))
15647 if (TREE_CODE (arg) == METHOD_TYPE)
15648 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15650 arg = build_pointer_type (arg);
15652 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15654 /* We don't copy orig_targs for this because if we have already deduced
15655 some template args from previous args, unify would complain when we
15656 try to deduce a template parameter for the same argument, even though
15657 there isn't really a conflict. */
15658 nargs = TREE_VEC_LENGTH (targs);
15659 tempargs = make_tree_vec (nargs);
15661 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15664 /* First make sure we didn't deduce anything that conflicts with
15665 explicitly specified args. */
15666 for (i = nargs; i--; )
15668 tree elt = TREE_VEC_ELT (tempargs, i);
15669 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15673 else if (uses_template_parms (elt))
15674 /* Since we're unifying against ourselves, we will fill in
15675 template args used in the function parm list with our own
15676 template parms. Discard them. */
15677 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15678 else if (oldelt && !template_args_equal (oldelt, elt))
15682 for (i = nargs; i--; )
15684 tree elt = TREE_VEC_ELT (tempargs, i);
15687 TREE_VEC_ELT (targs, i) = elt;
15693 /* PARM is a template class (perhaps with unbound template
15694 parameters). ARG is a fully instantiated type. If ARG can be
15695 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15696 TARGS are as for unify. */
15699 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15702 tree copy_of_targs;
15704 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15705 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15706 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15709 /* We need to make a new template argument vector for the call to
15710 unify. If we used TARGS, we'd clutter it up with the result of
15711 the attempted unification, even if this class didn't work out.
15712 We also don't want to commit ourselves to all the unifications
15713 we've already done, since unification is supposed to be done on
15714 an argument-by-argument basis. In other words, consider the
15715 following pathological case:
15717 template <int I, int J, int K>
15720 template <int I, int J>
15721 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15723 template <int I, int J, int K>
15724 void f(S<I, J, K>, S<I, I, I>);
15733 Now, by the time we consider the unification involving `s2', we
15734 already know that we must have `f<0, 0, 0>'. But, even though
15735 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15736 because there are two ways to unify base classes of S<0, 1, 2>
15737 with S<I, I, I>. If we kept the already deduced knowledge, we
15738 would reject the possibility I=1. */
15739 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15741 /* If unification failed, we're done. */
15742 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15743 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15749 /* Given a template type PARM and a class type ARG, find the unique
15750 base type in ARG that is an instance of PARM. We do not examine
15751 ARG itself; only its base-classes. If there is not exactly one
15752 appropriate base class, return NULL_TREE. PARM may be the type of
15753 a partial specialization, as well as a plain template type. Used
15756 static enum template_base_result
15757 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15758 bool explain_p, tree *result)
15760 tree rval = NULL_TREE;
15763 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15765 binfo = TYPE_BINFO (complete_type (arg));
15768 /* The type could not be completed. */
15769 *result = NULL_TREE;
15770 return tbr_incomplete_type;
15773 /* Walk in inheritance graph order. The search order is not
15774 important, and this avoids multiple walks of virtual bases. */
15775 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15777 tree r = try_class_unification (tparms, targs, parm,
15778 BINFO_TYPE (binfo), explain_p);
15782 /* If there is more than one satisfactory baseclass, then:
15786 If they yield more than one possible deduced A, the type
15790 if (rval && !same_type_p (r, rval))
15792 *result = NULL_TREE;
15793 return tbr_ambiguous_baseclass;
15801 return tbr_success;
15804 /* Returns the level of DECL, which declares a template parameter. */
15807 template_decl_level (tree decl)
15809 switch (TREE_CODE (decl))
15812 case TEMPLATE_DECL:
15813 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15816 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15819 gcc_unreachable ();
15824 /* Decide whether ARG can be unified with PARM, considering only the
15825 cv-qualifiers of each type, given STRICT as documented for unify.
15826 Returns nonzero iff the unification is OK on that basis. */
15829 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15831 int arg_quals = cp_type_quals (arg);
15832 int parm_quals = cp_type_quals (parm);
15834 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15835 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15837 /* Although a CVR qualifier is ignored when being applied to a
15838 substituted template parameter ([8.3.2]/1 for example), that
15839 does not allow us to unify "const T" with "int&" because both
15840 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15841 It is ok when we're allowing additional CV qualifiers
15842 at the outer level [14.8.2.1]/3,1st bullet. */
15843 if ((TREE_CODE (arg) == REFERENCE_TYPE
15844 || TREE_CODE (arg) == FUNCTION_TYPE
15845 || TREE_CODE (arg) == METHOD_TYPE)
15846 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15849 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15850 && (parm_quals & TYPE_QUAL_RESTRICT))
15854 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15855 && (arg_quals & parm_quals) != parm_quals)
15858 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15859 && (parm_quals & arg_quals) != arg_quals)
15865 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15867 template_parm_level_and_index (tree parm, int* level, int* index)
15869 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15870 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15871 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15873 *index = TEMPLATE_TYPE_IDX (parm);
15874 *level = TEMPLATE_TYPE_LEVEL (parm);
15878 *index = TEMPLATE_PARM_IDX (parm);
15879 *level = TEMPLATE_PARM_LEVEL (parm);
15883 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15885 if (unify (TP, TA, P, A, S, EP)) \
15889 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15890 expansion at the end of PACKED_PARMS. Returns 0 if the type
15891 deduction succeeds, 1 otherwise. STRICT is the same as in
15892 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15893 call argument list. We'll need to adjust the arguments to make them
15894 types. SUBR tells us if this is from a recursive call to
15895 type_unification_real, or for comparing two template argument
15899 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15900 tree packed_args, unification_kind_t strict,
15901 bool subr, bool explain_p)
15904 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15905 tree pattern = PACK_EXPANSION_PATTERN (parm);
15906 tree pack, packs = NULL_TREE;
15907 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15908 int len = TREE_VEC_LENGTH (packed_args);
15910 /* Determine the parameter packs we will be deducing from the
15911 pattern, and record their current deductions. */
15912 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15913 pack; pack = TREE_CHAIN (pack))
15915 tree parm_pack = TREE_VALUE (pack);
15918 /* Determine the index and level of this parameter pack. */
15919 template_parm_level_and_index (parm_pack, &level, &idx);
15921 /* Keep track of the parameter packs and their corresponding
15923 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15924 TREE_TYPE (packs) = make_tree_vec (len - start);
15927 /* Loop through all of the arguments that have not yet been
15928 unified and unify each with the pattern. */
15929 for (i = start; i < len; i++)
15932 bool any_explicit = false;
15933 tree arg = TREE_VEC_ELT (packed_args, i);
15935 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
15936 or the element of its argument pack at the current index if
15937 this argument was explicitly specified. */
15938 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15942 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15945 if (TREE_VALUE (pack)
15946 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
15947 && (i < TREE_VEC_LENGTH (pargs)))
15949 any_explicit = true;
15950 arg = TREE_VEC_ELT (pargs, i);
15952 TMPL_ARG (targs, level, idx) = arg;
15955 /* If we had explicit template arguments, substitute them into the
15956 pattern before deduction. */
15959 /* Some arguments might still be unspecified or dependent. */
15961 ++processing_template_decl;
15962 dependent = any_dependent_template_arguments_p (targs);
15964 --processing_template_decl;
15965 parm = tsubst (pattern, targs,
15966 explain_p ? tf_warning_or_error : tf_none,
15969 --processing_template_decl;
15970 if (parm == error_mark_node)
15976 /* Unify the pattern with the current argument. */
15977 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15978 LOOKUP_IMPLICIT, explain_p))
15981 /* For each parameter pack, collect the deduced value. */
15982 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15985 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15987 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15988 TMPL_ARG (targs, level, idx);
15992 /* Verify that the results of unification with the parameter packs
15993 produce results consistent with what we've seen before, and make
15994 the deduced argument packs available. */
15995 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15997 tree old_pack = TREE_VALUE (pack);
15998 tree new_args = TREE_TYPE (pack);
15999 int i, len = TREE_VEC_LENGTH (new_args);
16001 bool nondeduced_p = false;
16003 /* By default keep the original deduced argument pack.
16004 If necessary, more specific code is going to update the
16005 resulting deduced argument later down in this function. */
16006 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16007 TMPL_ARG (targs, level, idx) = old_pack;
16009 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16010 actually deduce anything. */
16011 for (i = 0; i < len && !nondeduced_p; ++i)
16012 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16013 nondeduced_p = true;
16017 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16019 /* If we had fewer function args than explicit template args,
16020 just use the explicits. */
16021 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16022 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16023 if (len < explicit_len)
16024 new_args = explicit_args;
16030 /* Build the deduced *_ARGUMENT_PACK. */
16031 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16033 result = make_node (NONTYPE_ARGUMENT_PACK);
16034 TREE_TYPE (result) =
16035 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16036 TREE_CONSTANT (result) = 1;
16039 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16041 SET_ARGUMENT_PACK_ARGS (result, new_args);
16043 /* Note the deduced argument packs for this parameter
16045 TMPL_ARG (targs, level, idx) = result;
16047 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16048 && (ARGUMENT_PACK_ARGS (old_pack)
16049 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16051 /* We only had the explicitly-provided arguments before, but
16052 now we have a complete set of arguments. */
16053 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16055 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16056 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16057 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16061 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16062 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16064 if (!comp_template_args_with_info (old_args, new_args,
16065 &bad_old_arg, &bad_new_arg))
16066 /* Inconsistent unification of this parameter pack. */
16067 return unify_parameter_pack_inconsistent (explain_p,
16073 return unify_success (explain_p);
16076 /* Deduce the value of template parameters. TPARMS is the (innermost)
16077 set of template parameters to a template. TARGS is the bindings
16078 for those template parameters, as determined thus far; TARGS may
16079 include template arguments for outer levels of template parameters
16080 as well. PARM is a parameter to a template function, or a
16081 subcomponent of that parameter; ARG is the corresponding argument.
16082 This function attempts to match PARM with ARG in a manner
16083 consistent with the existing assignments in TARGS. If more values
16084 are deduced, then TARGS is updated.
16086 Returns 0 if the type deduction succeeds, 1 otherwise. The
16087 parameter STRICT is a bitwise or of the following flags:
16090 Require an exact match between PARM and ARG.
16091 UNIFY_ALLOW_MORE_CV_QUAL:
16092 Allow the deduced ARG to be more cv-qualified (by qualification
16093 conversion) than ARG.
16094 UNIFY_ALLOW_LESS_CV_QUAL:
16095 Allow the deduced ARG to be less cv-qualified than ARG.
16096 UNIFY_ALLOW_DERIVED:
16097 Allow the deduced ARG to be a template base class of ARG,
16098 or a pointer to a template base class of the type pointed to by
16100 UNIFY_ALLOW_INTEGER:
16101 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16102 case for more information.
16103 UNIFY_ALLOW_OUTER_LEVEL:
16104 This is the outermost level of a deduction. Used to determine validity
16105 of qualification conversions. A valid qualification conversion must
16106 have const qualified pointers leading up to the inner type which
16107 requires additional CV quals, except at the outer level, where const
16108 is not required [conv.qual]. It would be normal to set this flag in
16109 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16110 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16111 This is the outermost level of a deduction, and PARM can be more CV
16112 qualified at this point.
16113 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16114 This is the outermost level of a deduction, and PARM can be less CV
16115 qualified at this point. */
16118 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16124 int strict_in = strict;
16126 /* I don't think this will do the right thing with respect to types.
16127 But the only case I've seen it in so far has been array bounds, where
16128 signedness is the only information lost, and I think that will be
16130 while (TREE_CODE (parm) == NOP_EXPR)
16131 parm = TREE_OPERAND (parm, 0);
16133 if (arg == error_mark_node)
16134 return unify_invalid (explain_p);
16135 if (arg == unknown_type_node
16136 || arg == init_list_type_node)
16137 /* We can't deduce anything from this, but we might get all the
16138 template args from other function args. */
16139 return unify_success (explain_p);
16141 /* If PARM uses template parameters, then we can't bail out here,
16142 even if ARG == PARM, since we won't record unifications for the
16143 template parameters. We might need them if we're trying to
16144 figure out which of two things is more specialized. */
16145 if (arg == parm && !uses_template_parms (parm))
16146 return unify_success (explain_p);
16148 /* Handle init lists early, so the rest of the function can assume
16149 we're dealing with a type. */
16150 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16154 tree orig_parm = parm;
16156 /* Replace T with std::initializer_list<T> for deduction. */
16157 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16158 && flag_deduce_init_list)
16159 parm = listify (parm);
16161 if (!is_std_init_list (parm))
16162 /* We can only deduce from an initializer list argument if the
16163 parameter is std::initializer_list; otherwise this is a
16164 non-deduced context. */
16165 return unify_success (explain_p);
16167 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16169 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16171 int elt_strict = strict;
16173 if (elt == error_mark_node)
16174 return unify_invalid (explain_p);
16176 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16178 tree type = TREE_TYPE (elt);
16179 /* It should only be possible to get here for a call. */
16180 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16181 elt_strict |= maybe_adjust_types_for_deduction
16182 (DEDUCE_CALL, &elttype, &type, elt);
16186 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16190 /* If the std::initializer_list<T> deduction worked, replace the
16191 deduced A with std::initializer_list<A>. */
16192 if (orig_parm != parm)
16194 idx = TEMPLATE_TYPE_IDX (orig_parm);
16195 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16196 targ = listify (targ);
16197 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16199 return unify_success (explain_p);
16202 /* Immediately reject some pairs that won't unify because of
16203 cv-qualification mismatches. */
16204 if (TREE_CODE (arg) == TREE_CODE (parm)
16206 /* It is the elements of the array which hold the cv quals of an array
16207 type, and the elements might be template type parms. We'll check
16208 when we recurse. */
16209 && TREE_CODE (arg) != ARRAY_TYPE
16210 /* We check the cv-qualifiers when unifying with template type
16211 parameters below. We want to allow ARG `const T' to unify with
16212 PARM `T' for example, when computing which of two templates
16213 is more specialized, for example. */
16214 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16215 && !check_cv_quals_for_unify (strict_in, arg, parm))
16216 return unify_cv_qual_mismatch (explain_p, parm, arg);
16218 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16219 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16220 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16221 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16222 strict &= ~UNIFY_ALLOW_DERIVED;
16223 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16224 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16226 switch (TREE_CODE (parm))
16228 case TYPENAME_TYPE:
16230 case UNBOUND_CLASS_TEMPLATE:
16231 /* In a type which contains a nested-name-specifier, template
16232 argument values cannot be deduced for template parameters used
16233 within the nested-name-specifier. */
16234 return unify_success (explain_p);
16236 case TEMPLATE_TYPE_PARM:
16237 case TEMPLATE_TEMPLATE_PARM:
16238 case BOUND_TEMPLATE_TEMPLATE_PARM:
16239 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16240 if (tparm == error_mark_node)
16241 return unify_invalid (explain_p);
16243 if (TEMPLATE_TYPE_LEVEL (parm)
16244 != template_decl_level (tparm))
16245 /* The PARM is not one we're trying to unify. Just check
16246 to see if it matches ARG. */
16248 if (TREE_CODE (arg) == TREE_CODE (parm)
16249 && same_type_p (parm, arg))
16250 return unify_success (explain_p);
16252 return unify_type_mismatch (explain_p, parm, arg);
16254 idx = TEMPLATE_TYPE_IDX (parm);
16255 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16256 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16258 /* Check for mixed types and values. */
16259 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16260 && TREE_CODE (tparm) != TYPE_DECL)
16261 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16262 && TREE_CODE (tparm) != TEMPLATE_DECL))
16263 gcc_unreachable ();
16265 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16267 /* ARG must be constructed from a template class or a template
16268 template parameter. */
16269 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16270 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16271 return unify_template_deduction_failure (explain_p, parm, arg);
16274 tree parmvec = TYPE_TI_ARGS (parm);
16275 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16276 tree full_argvec = add_to_template_args (targs, argvec);
16278 = DECL_INNERMOST_TEMPLATE_PARMS
16279 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16281 int parm_variadic_p = 0;
16283 /* The resolution to DR150 makes clear that default
16284 arguments for an N-argument may not be used to bind T
16285 to a template template parameter with fewer than N
16286 parameters. It is not safe to permit the binding of
16287 default arguments as an extension, as that may change
16288 the meaning of a conforming program. Consider:
16290 struct Dense { static const unsigned int dim = 1; };
16292 template <template <typename> class View,
16294 void operator+(float, View<Block> const&);
16296 template <typename Block,
16297 unsigned int Dim = Block::dim>
16298 struct Lvalue_proxy { operator float() const; };
16302 Lvalue_proxy<Dense> p;
16307 Here, if Lvalue_proxy is permitted to bind to View, then
16308 the global operator+ will be used; if they are not, the
16309 Lvalue_proxy will be converted to float. */
16310 if (coerce_template_parms (parm_parms,
16312 TYPE_TI_TEMPLATE (parm),
16314 ? tf_warning_or_error
16316 /*require_all_args=*/true,
16317 /*use_default_args=*/false)
16318 == error_mark_node)
16321 /* Deduce arguments T, i from TT<T> or TT<i>.
16322 We check each element of PARMVEC and ARGVEC individually
16323 rather than the whole TREE_VEC since they can have
16324 different number of elements. */
16326 parmvec = expand_template_argument_pack (parmvec);
16327 argvec = expand_template_argument_pack (argvec);
16329 len = TREE_VEC_LENGTH (parmvec);
16331 /* Check if the parameters end in a pack, making them
16334 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16335 parm_variadic_p = 1;
16337 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16338 return unify_too_few_arguments (explain_p,
16339 TREE_VEC_LENGTH (argvec), len);
16341 for (i = 0; i < len - parm_variadic_p; ++i)
16343 RECUR_AND_CHECK_FAILURE (tparms, targs,
16344 TREE_VEC_ELT (parmvec, i),
16345 TREE_VEC_ELT (argvec, i),
16346 UNIFY_ALLOW_NONE, explain_p);
16349 if (parm_variadic_p
16350 && unify_pack_expansion (tparms, targs,
16353 /*subr=*/true, explain_p))
16356 arg = TYPE_TI_TEMPLATE (arg);
16358 /* Fall through to deduce template name. */
16361 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16362 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16364 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16366 /* Simple cases: Value already set, does match or doesn't. */
16367 if (targ != NULL_TREE && template_args_equal (targ, arg))
16368 return unify_success (explain_p);
16370 return unify_inconsistency (explain_p, parm, targ, arg);
16374 /* If PARM is `const T' and ARG is only `int', we don't have
16375 a match unless we are allowing additional qualification.
16376 If ARG is `const int' and PARM is just `T' that's OK;
16377 that binds `const int' to `T'. */
16378 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16380 return unify_cv_qual_mismatch (explain_p, parm, arg);
16382 /* Consider the case where ARG is `const volatile int' and
16383 PARM is `const T'. Then, T should be `volatile int'. */
16384 arg = cp_build_qualified_type_real
16385 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16386 if (arg == error_mark_node)
16387 return unify_invalid (explain_p);
16389 /* Simple cases: Value already set, does match or doesn't. */
16390 if (targ != NULL_TREE && same_type_p (targ, arg))
16391 return unify_success (explain_p);
16393 return unify_inconsistency (explain_p, parm, targ, arg);
16395 /* Make sure that ARG is not a variable-sized array. (Note
16396 that were talking about variable-sized arrays (like
16397 `int[n]'), rather than arrays of unknown size (like
16398 `int[]').) We'll get very confused by such a type since
16399 the bound of the array is not constant, and therefore
16400 not mangleable. Besides, such types are not allowed in
16401 ISO C++, so we can do as we please here. We do allow
16402 them for 'auto' deduction, since that isn't ABI-exposed. */
16403 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16404 return unify_vla_arg (explain_p, arg);
16406 /* Strip typedefs as in convert_template_argument. */
16407 arg = canonicalize_type_argument (arg, tf_none);
16410 /* If ARG is a parameter pack or an expansion, we cannot unify
16411 against it unless PARM is also a parameter pack. */
16412 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16413 && !template_parameter_pack_p (parm))
16414 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16416 /* If the argument deduction results is a METHOD_TYPE,
16417 then there is a problem.
16418 METHOD_TYPE doesn't map to any real C++ type the result of
16419 the deduction can not be of that type. */
16420 if (TREE_CODE (arg) == METHOD_TYPE)
16421 return unify_method_type_error (explain_p, arg);
16423 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16424 return unify_success (explain_p);
16426 case TEMPLATE_PARM_INDEX:
16427 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16428 if (tparm == error_mark_node)
16429 return unify_invalid (explain_p);
16431 if (TEMPLATE_PARM_LEVEL (parm)
16432 != template_decl_level (tparm))
16434 /* The PARM is not one we're trying to unify. Just check
16435 to see if it matches ARG. */
16436 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16437 && cp_tree_equal (parm, arg));
16439 unify_expression_unequal (explain_p, parm, arg);
16443 idx = TEMPLATE_PARM_IDX (parm);
16444 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16448 int x = !cp_tree_equal (targ, arg);
16450 unify_inconsistency (explain_p, parm, targ, arg);
16454 /* [temp.deduct.type] If, in the declaration of a function template
16455 with a non-type template-parameter, the non-type
16456 template-parameter is used in an expression in the function
16457 parameter-list and, if the corresponding template-argument is
16458 deduced, the template-argument type shall match the type of the
16459 template-parameter exactly, except that a template-argument
16460 deduced from an array bound may be of any integral type.
16461 The non-type parameter might use already deduced type parameters. */
16462 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16463 if (!TREE_TYPE (arg))
16464 /* Template-parameter dependent expression. Just accept it for now.
16465 It will later be processed in convert_template_argument. */
16467 else if (same_type_p (TREE_TYPE (arg), tparm))
16469 else if ((strict & UNIFY_ALLOW_INTEGER)
16470 && (TREE_CODE (tparm) == INTEGER_TYPE
16471 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16472 /* Convert the ARG to the type of PARM; the deduced non-type
16473 template argument must exactly match the types of the
16474 corresponding parameter. */
16475 arg = fold (build_nop (tparm, arg));
16476 else if (uses_template_parms (tparm))
16477 /* We haven't deduced the type of this parameter yet. Try again
16479 return unify_success (explain_p);
16481 return unify_type_mismatch (explain_p, tparm, arg);
16483 /* If ARG is a parameter pack or an expansion, we cannot unify
16484 against it unless PARM is also a parameter pack. */
16485 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16486 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16487 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16489 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16490 return unify_success (explain_p);
16494 /* A pointer-to-member constant can be unified only with
16495 another constant. */
16496 if (TREE_CODE (arg) != PTRMEM_CST)
16497 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16499 /* Just unify the class member. It would be useless (and possibly
16500 wrong, depending on the strict flags) to unify also
16501 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16502 arg refer to the same variable, even if through different
16503 classes. For instance:
16505 struct A { int x; };
16508 Unification of &A::x and &B::x must succeed. */
16509 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16510 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16515 if (TREE_CODE (arg) != POINTER_TYPE)
16516 return unify_type_mismatch (explain_p, parm, arg);
16518 /* [temp.deduct.call]
16520 A can be another pointer or pointer to member type that can
16521 be converted to the deduced A via a qualification
16522 conversion (_conv.qual_).
16524 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16525 This will allow for additional cv-qualification of the
16526 pointed-to types if appropriate. */
16528 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16529 /* The derived-to-base conversion only persists through one
16530 level of pointers. */
16531 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16533 return unify (tparms, targs, TREE_TYPE (parm),
16534 TREE_TYPE (arg), strict, explain_p);
16537 case REFERENCE_TYPE:
16538 if (TREE_CODE (arg) != REFERENCE_TYPE)
16539 return unify_type_mismatch (explain_p, parm, arg);
16540 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16541 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16544 if (TREE_CODE (arg) != ARRAY_TYPE)
16545 return unify_type_mismatch (explain_p, parm, arg);
16546 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16547 != (TYPE_DOMAIN (arg) == NULL_TREE))
16548 return unify_type_mismatch (explain_p, parm, arg);
16549 if (TYPE_DOMAIN (parm) != NULL_TREE)
16556 /* Our representation of array types uses "N - 1" as the
16557 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16558 not an integer constant. We cannot unify arbitrarily
16559 complex expressions, so we eliminate the MINUS_EXPRs
16561 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16562 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16565 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16566 parm_max = TREE_OPERAND (parm_max, 0);
16568 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16569 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16572 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16573 trying to unify the type of a variable with the type
16574 of a template parameter. For example:
16576 template <unsigned int N>
16577 void f (char (&) [N]);
16584 Here, the type of the ARG will be "int [g(i)]", and
16585 may be a SAVE_EXPR, etc. */
16586 if (TREE_CODE (arg_max) != MINUS_EXPR)
16587 return unify_vla_arg (explain_p, arg);
16588 arg_max = TREE_OPERAND (arg_max, 0);
16591 /* If only one of the bounds used a MINUS_EXPR, compensate
16592 by adding one to the other bound. */
16593 if (parm_cst && !arg_cst)
16594 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16598 else if (arg_cst && !parm_cst)
16599 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16604 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16605 UNIFY_ALLOW_INTEGER, explain_p);
16607 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16608 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16615 case ENUMERAL_TYPE:
16618 if (TREE_CODE (arg) != TREE_CODE (parm))
16619 return unify_type_mismatch (explain_p, parm, arg);
16621 /* We have already checked cv-qualification at the top of the
16623 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16624 return unify_type_mismatch (explain_p, parm, arg);
16626 /* As far as unification is concerned, this wins. Later checks
16627 will invalidate it if necessary. */
16628 return unify_success (explain_p);
16630 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16631 /* Type INTEGER_CST can come from ordinary constant template args. */
16633 while (TREE_CODE (arg) == NOP_EXPR)
16634 arg = TREE_OPERAND (arg, 0);
16636 if (TREE_CODE (arg) != INTEGER_CST)
16637 return unify_template_argument_mismatch (explain_p, parm, arg);
16638 return (tree_int_cst_equal (parm, arg)
16639 ? unify_success (explain_p)
16640 : unify_template_argument_mismatch (explain_p, parm, arg));
16644 int i, len, argslen;
16645 int parm_variadic_p = 0;
16647 if (TREE_CODE (arg) != TREE_VEC)
16648 return unify_template_argument_mismatch (explain_p, parm, arg);
16650 len = TREE_VEC_LENGTH (parm);
16651 argslen = TREE_VEC_LENGTH (arg);
16653 /* Check for pack expansions in the parameters. */
16654 for (i = 0; i < len; ++i)
16656 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16659 /* We can unify against something with a trailing
16661 parm_variadic_p = 1;
16663 /* [temp.deduct.type]/9: If the template argument list of
16664 P contains a pack expansion that is not the last
16665 template argument, the entire template argument list
16666 is a non-deduced context. */
16667 return unify_success (explain_p);
16671 /* If we don't have enough arguments to satisfy the parameters
16672 (not counting the pack expression at the end), or we have
16673 too many arguments for a parameter list that doesn't end in
16674 a pack expression, we can't unify. */
16675 if (parm_variadic_p
16676 ? argslen < len - parm_variadic_p
16678 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16680 /* Unify all of the parameters that precede the (optional)
16681 pack expression. */
16682 for (i = 0; i < len - parm_variadic_p; ++i)
16684 RECUR_AND_CHECK_FAILURE (tparms, targs,
16685 TREE_VEC_ELT (parm, i),
16686 TREE_VEC_ELT (arg, i),
16687 UNIFY_ALLOW_NONE, explain_p);
16689 if (parm_variadic_p)
16690 return unify_pack_expansion (tparms, targs, parm, arg,
16692 /*subr=*/true, explain_p);
16693 return unify_success (explain_p);
16698 if (TREE_CODE (arg) != TREE_CODE (parm))
16699 return unify_type_mismatch (explain_p, parm, arg);
16701 if (TYPE_PTRMEMFUNC_P (parm))
16703 if (!TYPE_PTRMEMFUNC_P (arg))
16704 return unify_type_mismatch (explain_p, parm, arg);
16706 return unify (tparms, targs,
16707 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16708 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16709 strict, explain_p);
16712 if (CLASSTYPE_TEMPLATE_INFO (parm))
16714 tree t = NULL_TREE;
16716 if (strict_in & UNIFY_ALLOW_DERIVED)
16718 /* First, we try to unify the PARM and ARG directly. */
16719 t = try_class_unification (tparms, targs,
16720 parm, arg, explain_p);
16724 /* Fallback to the special case allowed in
16725 [temp.deduct.call]:
16727 If P is a class, and P has the form
16728 template-id, then A can be a derived class of
16729 the deduced A. Likewise, if P is a pointer to
16730 a class of the form template-id, A can be a
16731 pointer to a derived class pointed to by the
16733 enum template_base_result r;
16734 r = get_template_base (tparms, targs, parm, arg,
16738 return unify_no_common_base (explain_p, r, parm, arg);
16741 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16742 && (CLASSTYPE_TI_TEMPLATE (parm)
16743 == CLASSTYPE_TI_TEMPLATE (arg)))
16744 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16745 Then, we should unify `int' and `U'. */
16748 /* There's no chance of unification succeeding. */
16749 return unify_type_mismatch (explain_p, parm, arg);
16751 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16752 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16754 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16755 return unify_type_mismatch (explain_p, parm, arg);
16756 return unify_success (explain_p);
16759 case FUNCTION_TYPE:
16761 unsigned int nargs;
16766 if (TREE_CODE (arg) != TREE_CODE (parm))
16767 return unify_type_mismatch (explain_p, parm, arg);
16769 /* CV qualifications for methods can never be deduced, they must
16770 match exactly. We need to check them explicitly here,
16771 because type_unification_real treats them as any other
16772 cv-qualified parameter. */
16773 if (TREE_CODE (parm) == METHOD_TYPE
16774 && (!check_cv_quals_for_unify
16776 class_of_this_parm (arg),
16777 class_of_this_parm (parm))))
16778 return unify_cv_qual_mismatch (explain_p, parm, arg);
16780 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16781 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16783 nargs = list_length (TYPE_ARG_TYPES (arg));
16784 args = XALLOCAVEC (tree, nargs);
16785 for (a = TYPE_ARG_TYPES (arg), i = 0;
16786 a != NULL_TREE && a != void_list_node;
16787 a = TREE_CHAIN (a), ++i)
16788 args[i] = TREE_VALUE (a);
16791 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16792 args, nargs, 1, DEDUCE_EXACT,
16793 LOOKUP_NORMAL, explain_p);
16797 /* Unify a pointer to member with a pointer to member function, which
16798 deduces the type of the member as a function type. */
16799 if (TYPE_PTRMEMFUNC_P (arg))
16804 /* Check top-level cv qualifiers */
16805 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16806 return unify_cv_qual_mismatch (explain_p, parm, arg);
16808 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16809 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16810 UNIFY_ALLOW_NONE, explain_p);
16812 /* Determine the type of the function we are unifying against. */
16813 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16815 build_function_type (TREE_TYPE (method_type),
16816 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16818 /* Extract the cv-qualifiers of the member function from the
16819 implicit object parameter and place them on the function
16820 type to be restored later. */
16821 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16822 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16825 if (TREE_CODE (arg) != OFFSET_TYPE)
16826 return unify_type_mismatch (explain_p, parm, arg);
16827 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16828 TYPE_OFFSET_BASETYPE (arg),
16829 UNIFY_ALLOW_NONE, explain_p);
16830 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16831 strict, explain_p);
16834 if (DECL_TEMPLATE_PARM_P (parm))
16835 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16836 if (arg != integral_constant_value (parm))
16837 return unify_template_argument_mismatch (explain_p, parm, arg);
16838 return unify_success (explain_p);
16841 case TEMPLATE_DECL:
16842 /* Matched cases are handled by the ARG == PARM test above. */
16843 return unify_template_argument_mismatch (explain_p, parm, arg);
16846 /* A non-type template parameter that is a variable should be a
16847 an integral constant, in which case, it whould have been
16848 folded into its (constant) value. So we should not be getting
16849 a variable here. */
16850 gcc_unreachable ();
16852 case TYPE_ARGUMENT_PACK:
16853 case NONTYPE_ARGUMENT_PACK:
16854 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16855 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16858 case DECLTYPE_TYPE:
16859 case UNDERLYING_TYPE:
16860 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16861 or UNDERLYING_TYPE nodes. */
16862 return unify_success (explain_p);
16865 /* Unification fails if we hit an error node. */
16866 return unify_invalid (explain_p);
16869 /* An unresolved overload is a nondeduced context. */
16870 if (type_unknown_p (parm))
16871 return unify_success (explain_p);
16872 gcc_assert (EXPR_P (parm));
16874 /* We must be looking at an expression. This can happen with
16878 void foo(S<I>, S<I + 2>);
16880 This is a "nondeduced context":
16884 The nondeduced contexts are:
16886 --A type that is a template-id in which one or more of
16887 the template-arguments is an expression that references
16888 a template-parameter.
16890 In these cases, we assume deduction succeeded, but don't
16891 actually infer any unifications. */
16893 if (!uses_template_parms (parm)
16894 && !template_args_equal (parm, arg))
16895 return unify_expression_unequal (explain_p, parm, arg);
16897 return unify_success (explain_p);
16900 #undef RECUR_AND_CHECK_FAILURE
16902 /* Note that DECL can be defined in this translation unit, if
16906 mark_definable (tree decl)
16909 DECL_NOT_REALLY_EXTERN (decl) = 1;
16910 FOR_EACH_CLONE (clone, decl)
16911 DECL_NOT_REALLY_EXTERN (clone) = 1;
16914 /* Called if RESULT is explicitly instantiated, or is a member of an
16915 explicitly instantiated class. */
16918 mark_decl_instantiated (tree result, int extern_p)
16920 SET_DECL_EXPLICIT_INSTANTIATION (result);
16922 /* If this entity has already been written out, it's too late to
16923 make any modifications. */
16924 if (TREE_ASM_WRITTEN (result))
16927 if (TREE_CODE (result) != FUNCTION_DECL)
16928 /* The TREE_PUBLIC flag for function declarations will have been
16929 set correctly by tsubst. */
16930 TREE_PUBLIC (result) = 1;
16932 /* This might have been set by an earlier implicit instantiation. */
16933 DECL_COMDAT (result) = 0;
16936 DECL_NOT_REALLY_EXTERN (result) = 0;
16939 mark_definable (result);
16940 /* Always make artificials weak. */
16941 if (DECL_ARTIFICIAL (result) && flag_weak)
16942 comdat_linkage (result);
16943 /* For WIN32 we also want to put explicit instantiations in
16944 linkonce sections. */
16945 else if (TREE_PUBLIC (result))
16946 maybe_make_one_only (result);
16949 /* If EXTERN_P, then this function will not be emitted -- unless
16950 followed by an explicit instantiation, at which point its linkage
16951 will be adjusted. If !EXTERN_P, then this function will be
16952 emitted here. In neither circumstance do we want
16953 import_export_decl to adjust the linkage. */
16954 DECL_INTERFACE_KNOWN (result) = 1;
16957 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16958 important template arguments. If any are missing, we check whether
16959 they're important by using error_mark_node for substituting into any
16960 args that were used for partial ordering (the ones between ARGS and END)
16961 and seeing if it bubbles up. */
16964 check_undeduced_parms (tree targs, tree args, tree end)
16966 bool found = false;
16968 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16969 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16972 TREE_VEC_ELT (targs, i) = error_mark_node;
16976 for (; args != end; args = TREE_CHAIN (args))
16978 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16979 if (substed == error_mark_node)
16986 /* Given two function templates PAT1 and PAT2, return:
16988 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16989 -1 if PAT2 is more specialized than PAT1.
16990 0 if neither is more specialized.
16992 LEN indicates the number of parameters we should consider
16993 (defaulted parameters should not be considered).
16995 The 1998 std underspecified function template partial ordering, and
16996 DR214 addresses the issue. We take pairs of arguments, one from
16997 each of the templates, and deduce them against each other. One of
16998 the templates will be more specialized if all the *other*
16999 template's arguments deduce against its arguments and at least one
17000 of its arguments *does* *not* deduce against the other template's
17001 corresponding argument. Deduction is done as for class templates.
17002 The arguments used in deduction have reference and top level cv
17003 qualifiers removed. Iff both arguments were originally reference
17004 types *and* deduction succeeds in both directions, the template
17005 with the more cv-qualified argument wins for that pairing (if
17006 neither is more cv-qualified, they both are equal). Unlike regular
17007 deduction, after all the arguments have been deduced in this way,
17008 we do *not* verify the deduced template argument values can be
17009 substituted into non-deduced contexts.
17011 The logic can be a bit confusing here, because we look at deduce1 and
17012 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17013 can find template arguments for pat1 to make arg1 look like arg2, that
17014 means that arg2 is at least as specialized as arg1. */
17017 more_specialized_fn (tree pat1, tree pat2, int len)
17019 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17020 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17021 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17022 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17023 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17024 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17025 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17026 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17027 tree origs1, origs2;
17028 bool lose1 = false;
17029 bool lose2 = false;
17031 /* Remove the this parameter from non-static member functions. If
17032 one is a non-static member function and the other is not a static
17033 member function, remove the first parameter from that function
17034 also. This situation occurs for operator functions where we
17035 locate both a member function (with this pointer) and non-member
17036 operator (with explicit first operand). */
17037 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17039 len--; /* LEN is the number of significant arguments for DECL1 */
17040 args1 = TREE_CHAIN (args1);
17041 if (!DECL_STATIC_FUNCTION_P (decl2))
17042 args2 = TREE_CHAIN (args2);
17044 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17046 args2 = TREE_CHAIN (args2);
17047 if (!DECL_STATIC_FUNCTION_P (decl1))
17050 args1 = TREE_CHAIN (args1);
17054 /* If only one is a conversion operator, they are unordered. */
17055 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17058 /* Consider the return type for a conversion function */
17059 if (DECL_CONV_FN_P (decl1))
17061 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17062 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17066 processing_template_decl++;
17072 /* Stop when an ellipsis is seen. */
17073 && args1 != NULL_TREE && args2 != NULL_TREE)
17075 tree arg1 = TREE_VALUE (args1);
17076 tree arg2 = TREE_VALUE (args2);
17077 int deduce1, deduce2;
17081 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17082 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17084 /* When both arguments are pack expansions, we need only
17085 unify the patterns themselves. */
17086 arg1 = PACK_EXPANSION_PATTERN (arg1);
17087 arg2 = PACK_EXPANSION_PATTERN (arg2);
17089 /* This is the last comparison we need to do. */
17093 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17095 arg1 = TREE_TYPE (arg1);
17096 quals1 = cp_type_quals (arg1);
17099 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17101 arg2 = TREE_TYPE (arg2);
17102 quals2 = cp_type_quals (arg2);
17105 if ((quals1 < 0) != (quals2 < 0))
17107 /* Only of the args is a reference, see if we should apply
17108 array/function pointer decay to it. This is not part of
17109 DR214, but is, IMHO, consistent with the deduction rules
17110 for the function call itself, and with our earlier
17111 implementation of the underspecified partial ordering
17112 rules. (nathan). */
17115 switch (TREE_CODE (arg1))
17118 arg1 = TREE_TYPE (arg1);
17120 case FUNCTION_TYPE:
17121 arg1 = build_pointer_type (arg1);
17130 switch (TREE_CODE (arg2))
17133 arg2 = TREE_TYPE (arg2);
17135 case FUNCTION_TYPE:
17136 arg2 = build_pointer_type (arg2);
17145 arg1 = TYPE_MAIN_VARIANT (arg1);
17146 arg2 = TYPE_MAIN_VARIANT (arg2);
17148 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17150 int i, len2 = list_length (args2);
17151 tree parmvec = make_tree_vec (1);
17152 tree argvec = make_tree_vec (len2);
17155 /* Setup the parameter vector, which contains only ARG1. */
17156 TREE_VEC_ELT (parmvec, 0) = arg1;
17158 /* Setup the argument vector, which contains the remaining
17160 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17161 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17163 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17164 argvec, DEDUCE_EXACT,
17165 /*subr=*/true, /*explain_p=*/false)
17168 /* We cannot deduce in the other direction, because ARG1 is
17169 a pack expansion but ARG2 is not. */
17172 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17174 int i, len1 = list_length (args1);
17175 tree parmvec = make_tree_vec (1);
17176 tree argvec = make_tree_vec (len1);
17179 /* Setup the parameter vector, which contains only ARG1. */
17180 TREE_VEC_ELT (parmvec, 0) = arg2;
17182 /* Setup the argument vector, which contains the remaining
17184 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17185 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17187 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17188 argvec, DEDUCE_EXACT,
17189 /*subr=*/true, /*explain_p=*/false)
17192 /* We cannot deduce in the other direction, because ARG2 is
17193 a pack expansion but ARG1 is not.*/
17199 /* The normal case, where neither argument is a pack
17201 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17202 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17204 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17205 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17209 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17210 arg2, then arg2 is not as specialized as arg1. */
17216 /* "If, for a given type, deduction succeeds in both directions
17217 (i.e., the types are identical after the transformations above)
17218 and if the type from the argument template is more cv-qualified
17219 than the type from the parameter template (as described above)
17220 that type is considered to be more specialized than the other. If
17221 neither type is more cv-qualified than the other then neither type
17222 is more specialized than the other." */
17224 if (deduce1 && deduce2
17225 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17227 if ((quals1 & quals2) == quals2)
17229 if ((quals1 & quals2) == quals1)
17233 if (lose1 && lose2)
17234 /* We've failed to deduce something in either direction.
17235 These must be unordered. */
17238 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17239 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17240 /* We have already processed all of the arguments in our
17241 handing of the pack expansion type. */
17244 args1 = TREE_CHAIN (args1);
17245 args2 = TREE_CHAIN (args2);
17248 /* "In most cases, all template parameters must have values in order for
17249 deduction to succeed, but for partial ordering purposes a template
17250 parameter may remain without a value provided it is not used in the
17251 types being used for partial ordering."
17253 Thus, if we are missing any of the targs1 we need to substitute into
17254 origs1, then pat2 is not as specialized as pat1. This can happen when
17255 there is a nondeduced context. */
17256 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17258 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17261 processing_template_decl--;
17263 /* All things being equal, if the next argument is a pack expansion
17264 for one function but not for the other, prefer the
17265 non-variadic function. FIXME this is bogus; see c++/41958. */
17267 && args1 && TREE_VALUE (args1)
17268 && args2 && TREE_VALUE (args2))
17270 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17271 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17274 if (lose1 == lose2)
17282 /* Determine which of two partial specializations is more specialized.
17284 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17285 to the first partial specialization. The TREE_VALUE is the
17286 innermost set of template parameters for the partial
17287 specialization. PAT2 is similar, but for the second template.
17289 Return 1 if the first partial specialization is more specialized;
17290 -1 if the second is more specialized; 0 if neither is more
17293 See [temp.class.order] for information about determining which of
17294 two templates is more specialized. */
17297 more_specialized_class (tree pat1, tree pat2)
17302 bool any_deductions = false;
17304 tmpl1 = TREE_TYPE (pat1);
17305 tmpl2 = TREE_TYPE (pat2);
17307 /* Just like what happens for functions, if we are ordering between
17308 different class template specializations, we may encounter dependent
17309 types in the arguments, and we need our dependency check functions
17310 to behave correctly. */
17311 ++processing_template_decl;
17312 targs = get_class_bindings (TREE_VALUE (pat1),
17313 CLASSTYPE_TI_ARGS (tmpl1),
17314 CLASSTYPE_TI_ARGS (tmpl2));
17318 any_deductions = true;
17321 targs = get_class_bindings (TREE_VALUE (pat2),
17322 CLASSTYPE_TI_ARGS (tmpl2),
17323 CLASSTYPE_TI_ARGS (tmpl1));
17327 any_deductions = true;
17329 --processing_template_decl;
17331 /* In the case of a tie where at least one of the class templates
17332 has a parameter pack at the end, the template with the most
17333 non-packed parameters wins. */
17336 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17337 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17339 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17340 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17341 int len1 = TREE_VEC_LENGTH (args1);
17342 int len2 = TREE_VEC_LENGTH (args2);
17344 /* We don't count the pack expansion at the end. */
17345 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17347 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17352 else if (len1 < len2)
17359 /* Return the template arguments that will produce the function signature
17360 DECL from the function template FN, with the explicit template
17361 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17362 also match. Return NULL_TREE if no satisfactory arguments could be
17366 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17368 int ntparms = DECL_NTPARMS (fn);
17369 tree targs = make_tree_vec (ntparms);
17371 tree decl_arg_types;
17373 unsigned int nargs, ix;
17376 /* Substitute the explicit template arguments into the type of DECL.
17377 The call to fn_type_unification will handle substitution into the
17379 decl_type = TREE_TYPE (decl);
17380 if (explicit_args && uses_template_parms (decl_type))
17383 tree converted_args;
17385 if (DECL_TEMPLATE_INFO (decl))
17386 tmpl = DECL_TI_TEMPLATE (decl);
17388 /* We can get here for some invalid specializations. */
17392 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17393 explicit_args, NULL_TREE,
17395 /*require_all_args=*/false,
17396 /*use_default_args=*/false);
17397 if (converted_args == error_mark_node)
17400 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17401 if (decl_type == error_mark_node)
17405 /* Never do unification on the 'this' parameter. */
17406 decl_arg_types = skip_artificial_parms_for (decl,
17407 TYPE_ARG_TYPES (decl_type));
17409 nargs = list_length (decl_arg_types);
17410 args = XALLOCAVEC (tree, nargs);
17411 for (arg = decl_arg_types, ix = 0;
17412 arg != NULL_TREE && arg != void_list_node;
17413 arg = TREE_CHAIN (arg), ++ix)
17414 args[ix] = TREE_VALUE (arg);
17416 if (fn_type_unification (fn, explicit_args, targs,
17418 (check_rettype || DECL_CONV_FN_P (fn)
17419 ? TREE_TYPE (decl_type) : NULL_TREE),
17420 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17426 /* Return the innermost template arguments that, when applied to a
17427 template specialization whose innermost template parameters are
17428 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17431 For example, suppose we have:
17433 template <class T, class U> struct S {};
17434 template <class T> struct S<T*, int> {};
17436 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17437 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17438 int}. The resulting vector will be {double}, indicating that `T'
17439 is bound to `double'. */
17442 get_class_bindings (tree tparms, tree spec_args, tree args)
17444 int i, ntparms = TREE_VEC_LENGTH (tparms);
17446 tree innermost_deduced_args;
17448 innermost_deduced_args = make_tree_vec (ntparms);
17449 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17451 deduced_args = copy_node (args);
17452 SET_TMPL_ARGS_LEVEL (deduced_args,
17453 TMPL_ARGS_DEPTH (deduced_args),
17454 innermost_deduced_args);
17457 deduced_args = innermost_deduced_args;
17459 if (unify (tparms, deduced_args,
17460 INNERMOST_TEMPLATE_ARGS (spec_args),
17461 INNERMOST_TEMPLATE_ARGS (args),
17462 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17465 for (i = 0; i < ntparms; ++i)
17466 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17469 /* Verify that nondeduced template arguments agree with the type
17470 obtained from argument deduction.
17474 struct A { typedef int X; };
17475 template <class T, class U> struct C {};
17476 template <class T> struct C<T, typename T::X> {};
17478 Then with the instantiation `C<A, int>', we can deduce that
17479 `T' is `A' but unify () does not check whether `typename T::X'
17481 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17482 if (spec_args == error_mark_node
17483 /* We only need to check the innermost arguments; the other
17484 arguments will always agree. */
17485 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17486 INNERMOST_TEMPLATE_ARGS (args)))
17489 /* Now that we have bindings for all of the template arguments,
17490 ensure that the arguments deduced for the template template
17491 parameters have compatible template parameter lists. See the use
17492 of template_template_parm_bindings_ok_p in fn_type_unification
17493 for more information. */
17494 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17497 return deduced_args;
17500 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17501 Return the TREE_LIST node with the most specialized template, if
17502 any. If there is no most specialized template, the error_mark_node
17505 Note that this function does not look at, or modify, the
17506 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17507 returned is one of the elements of INSTANTIATIONS, callers may
17508 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17509 and retrieve it from the value returned. */
17512 most_specialized_instantiation (tree templates)
17516 ++processing_template_decl;
17519 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17523 if (get_bindings (TREE_VALUE (champ),
17524 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17525 NULL_TREE, /*check_ret=*/true))
17528 if (get_bindings (TREE_VALUE (fn),
17529 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17530 NULL_TREE, /*check_ret=*/true))
17537 /* Equally specialized, move to next function. If there
17538 is no next function, nothing's most specialized. */
17539 fn = TREE_CHAIN (fn);
17547 /* Now verify that champ is better than everything earlier in the
17548 instantiation list. */
17549 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17550 if (get_bindings (TREE_VALUE (champ),
17551 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17552 NULL_TREE, /*check_ret=*/true)
17553 || !get_bindings (TREE_VALUE (fn),
17554 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17555 NULL_TREE, /*check_ret=*/true))
17561 processing_template_decl--;
17564 return error_mark_node;
17569 /* If DECL is a specialization of some template, return the most
17570 general such template. Otherwise, returns NULL_TREE.
17572 For example, given:
17574 template <class T> struct S { template <class U> void f(U); };
17576 if TMPL is `template <class U> void S<int>::f(U)' this will return
17577 the full template. This function will not trace past partial
17578 specializations, however. For example, given in addition:
17580 template <class T> struct S<T*> { template <class U> void f(U); };
17582 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17583 `template <class T> template <class U> S<T*>::f(U)'. */
17586 most_general_template (tree decl)
17588 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17589 an immediate specialization. */
17590 if (TREE_CODE (decl) == FUNCTION_DECL)
17592 if (DECL_TEMPLATE_INFO (decl)) {
17593 decl = DECL_TI_TEMPLATE (decl);
17595 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17596 template friend. */
17597 if (TREE_CODE (decl) != TEMPLATE_DECL)
17603 /* Look for more and more general templates. */
17604 while (DECL_TEMPLATE_INFO (decl))
17606 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17607 (See cp-tree.h for details.) */
17608 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17611 if (CLASS_TYPE_P (TREE_TYPE (decl))
17612 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17615 /* Stop if we run into an explicitly specialized class template. */
17616 if (!DECL_NAMESPACE_SCOPE_P (decl)
17617 && DECL_CONTEXT (decl)
17618 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17621 decl = DECL_TI_TEMPLATE (decl);
17627 /* Return the most specialized of the class template partial
17628 specializations of TMPL which can produce TYPE, a specialization of
17629 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17630 a _TYPE node corresponding to the partial specialization, while the
17631 TREE_PURPOSE is the set of template arguments that must be
17632 substituted into the TREE_TYPE in order to generate TYPE.
17634 If the choice of partial specialization is ambiguous, a diagnostic
17635 is issued, and the error_mark_node is returned. If there are no
17636 partial specializations of TMPL matching TYPE, then NULL_TREE is
17640 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17642 tree list = NULL_TREE;
17648 tree outer_args = NULL_TREE;
17650 tmpl = most_general_template (tmpl);
17651 args = CLASSTYPE_TI_ARGS (type);
17653 /* For determining which partial specialization to use, only the
17654 innermost args are interesting. */
17655 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17657 outer_args = strip_innermost_template_args (args, 1);
17658 args = INNERMOST_TEMPLATE_ARGS (args);
17661 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17663 tree partial_spec_args;
17665 tree parms = TREE_VALUE (t);
17667 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17669 ++processing_template_decl;
17675 /* Discard the outer levels of args, and then substitute in the
17676 template args from the enclosing class. */
17677 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17678 partial_spec_args = tsubst_template_args
17679 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17681 /* PARMS already refers to just the innermost parms, but the
17682 template parms in partial_spec_args had their levels lowered
17683 by tsubst, so we need to do the same for the parm list. We
17684 can't just tsubst the TREE_VEC itself, as tsubst wants to
17685 treat a TREE_VEC as an argument vector. */
17686 parms = copy_node (parms);
17687 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17688 TREE_VEC_ELT (parms, i) =
17689 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17693 partial_spec_args =
17694 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17695 add_to_template_args (outer_args,
17696 partial_spec_args),
17698 /*require_all_args=*/true,
17699 /*use_default_args=*/true);
17701 --processing_template_decl;
17703 if (partial_spec_args == error_mark_node)
17704 return error_mark_node;
17706 spec_args = get_class_bindings (parms,
17712 spec_args = add_to_template_args (outer_args, spec_args);
17713 list = tree_cons (spec_args, TREE_VALUE (t), list);
17714 TREE_TYPE (list) = TREE_TYPE (t);
17721 ambiguous_p = false;
17724 t = TREE_CHAIN (t);
17725 for (; t; t = TREE_CHAIN (t))
17727 fate = more_specialized_class (champ, t);
17734 t = TREE_CHAIN (t);
17737 ambiguous_p = true;
17746 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17748 fate = more_specialized_class (champ, t);
17751 ambiguous_p = true;
17759 char *spaces = NULL;
17760 if (!(complain & tf_error))
17761 return error_mark_node;
17762 error ("ambiguous class template instantiation for %q#T", type);
17763 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17764 for (t = list; t; t = TREE_CHAIN (t))
17766 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17767 spaces = spaces ? spaces : get_spaces (str);
17770 return error_mark_node;
17776 /* Explicitly instantiate DECL. */
17779 do_decl_instantiation (tree decl, tree storage)
17781 tree result = NULL_TREE;
17784 if (!decl || decl == error_mark_node)
17785 /* An error occurred, for which grokdeclarator has already issued
17786 an appropriate message. */
17788 else if (! DECL_LANG_SPECIFIC (decl))
17790 error ("explicit instantiation of non-template %q#D", decl);
17793 else if (TREE_CODE (decl) == VAR_DECL)
17795 /* There is an asymmetry here in the way VAR_DECLs and
17796 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17797 the latter, the DECL we get back will be marked as a
17798 template instantiation, and the appropriate
17799 DECL_TEMPLATE_INFO will be set up. This does not happen for
17800 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17801 should handle VAR_DECLs as it currently handles
17803 if (!DECL_CLASS_SCOPE_P (decl))
17805 error ("%qD is not a static data member of a class template", decl);
17808 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17809 if (!result || TREE_CODE (result) != VAR_DECL)
17811 error ("no matching template for %qD found", decl);
17814 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17816 error ("type %qT for explicit instantiation %qD does not match "
17817 "declared type %qT", TREE_TYPE (result), decl,
17822 else if (TREE_CODE (decl) != FUNCTION_DECL)
17824 error ("explicit instantiation of %q#D", decl);
17830 /* Check for various error cases. Note that if the explicit
17831 instantiation is valid the RESULT will currently be marked as an
17832 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17833 until we get here. */
17835 if (DECL_TEMPLATE_SPECIALIZATION (result))
17837 /* DR 259 [temp.spec].
17839 Both an explicit instantiation and a declaration of an explicit
17840 specialization shall not appear in a program unless the explicit
17841 instantiation follows a declaration of the explicit specialization.
17843 For a given set of template parameters, if an explicit
17844 instantiation of a template appears after a declaration of an
17845 explicit specialization for that template, the explicit
17846 instantiation has no effect. */
17849 else if (DECL_EXPLICIT_INSTANTIATION (result))
17853 No program shall explicitly instantiate any template more
17856 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17857 the first instantiation was `extern' and the second is not,
17858 and EXTERN_P for the opposite case. */
17859 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17860 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17861 /* If an "extern" explicit instantiation follows an ordinary
17862 explicit instantiation, the template is instantiated. */
17866 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17868 error ("no matching template for %qD found", result);
17871 else if (!DECL_TEMPLATE_INFO (result))
17873 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17877 if (storage == NULL_TREE)
17879 else if (storage == ridpointers[(int) RID_EXTERN])
17881 if (!in_system_header && (cxx_dialect == cxx98))
17882 pedwarn (input_location, OPT_pedantic,
17883 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17888 error ("storage class %qD applied to template instantiation", storage);
17890 check_explicit_instantiation_namespace (result);
17891 mark_decl_instantiated (result, extern_p);
17893 instantiate_decl (result, /*defer_ok=*/1,
17894 /*expl_inst_class_mem_p=*/false);
17898 mark_class_instantiated (tree t, int extern_p)
17900 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17901 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17902 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17903 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17906 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17907 rest_of_type_compilation (t, 1);
17911 /* Called from do_type_instantiation through binding_table_foreach to
17912 do recursive instantiation for the type bound in ENTRY. */
17914 bt_instantiate_type_proc (binding_entry entry, void *data)
17916 tree storage = *(tree *) data;
17918 if (MAYBE_CLASS_TYPE_P (entry->type)
17919 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17920 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17923 /* Called from do_type_instantiation to instantiate a member
17924 (a member function or a static member variable) of an
17925 explicitly instantiated class template. */
17927 instantiate_class_member (tree decl, int extern_p)
17929 mark_decl_instantiated (decl, extern_p);
17931 instantiate_decl (decl, /*defer_ok=*/1,
17932 /*expl_inst_class_mem_p=*/true);
17935 /* Perform an explicit instantiation of template class T. STORAGE, if
17936 non-null, is the RID for extern, inline or static. COMPLAIN is
17937 nonzero if this is called from the parser, zero if called recursively,
17938 since the standard is unclear (as detailed below). */
17941 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17946 int previous_instantiation_extern_p = 0;
17948 if (TREE_CODE (t) == TYPE_DECL)
17951 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17954 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
17956 error ("explicit instantiation of non-class template %qD", tmpl);
17958 error ("explicit instantiation of non-template type %qT", t);
17964 if (!COMPLETE_TYPE_P (t))
17966 if (complain & tf_error)
17967 error ("explicit instantiation of %q#T before definition of template",
17972 if (storage != NULL_TREE)
17974 if (!in_system_header)
17976 if (storage == ridpointers[(int) RID_EXTERN])
17978 if (cxx_dialect == cxx98)
17979 pedwarn (input_location, OPT_pedantic,
17980 "ISO C++ 1998 forbids the use of %<extern%> on "
17981 "explicit instantiations");
17984 pedwarn (input_location, OPT_pedantic,
17985 "ISO C++ forbids the use of %qE"
17986 " on explicit instantiations", storage);
17989 if (storage == ridpointers[(int) RID_INLINE])
17991 else if (storage == ridpointers[(int) RID_EXTERN])
17993 else if (storage == ridpointers[(int) RID_STATIC])
17997 error ("storage class %qD applied to template instantiation",
18003 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18005 /* DR 259 [temp.spec].
18007 Both an explicit instantiation and a declaration of an explicit
18008 specialization shall not appear in a program unless the explicit
18009 instantiation follows a declaration of the explicit specialization.
18011 For a given set of template parameters, if an explicit
18012 instantiation of a template appears after a declaration of an
18013 explicit specialization for that template, the explicit
18014 instantiation has no effect. */
18017 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18021 No program shall explicitly instantiate any template more
18024 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18025 instantiation was `extern'. If EXTERN_P then the second is.
18026 These cases are OK. */
18027 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18029 if (!previous_instantiation_extern_p && !extern_p
18030 && (complain & tf_error))
18031 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18033 /* If we've already instantiated the template, just return now. */
18034 if (!CLASSTYPE_INTERFACE_ONLY (t))
18038 check_explicit_instantiation_namespace (TYPE_NAME (t));
18039 mark_class_instantiated (t, extern_p);
18047 /* In contrast to implicit instantiation, where only the
18048 declarations, and not the definitions, of members are
18049 instantiated, we have here:
18053 The explicit instantiation of a class template specialization
18054 implies the instantiation of all of its members not
18055 previously explicitly specialized in the translation unit
18056 containing the explicit instantiation.
18058 Of course, we can't instantiate member template classes, since
18059 we don't have any arguments for them. Note that the standard
18060 is unclear on whether the instantiation of the members are
18061 *explicit* instantiations or not. However, the most natural
18062 interpretation is that it should be an explicit instantiation. */
18065 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18066 if (TREE_CODE (tmp) == FUNCTION_DECL
18067 && DECL_TEMPLATE_INSTANTIATION (tmp))
18068 instantiate_class_member (tmp, extern_p);
18070 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18071 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18072 instantiate_class_member (tmp, extern_p);
18074 if (CLASSTYPE_NESTED_UTDS (t))
18075 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18076 bt_instantiate_type_proc, &storage);
18080 /* Given a function DECL, which is a specialization of TMPL, modify
18081 DECL to be a re-instantiation of TMPL with the same template
18082 arguments. TMPL should be the template into which tsubst'ing
18083 should occur for DECL, not the most general template.
18085 One reason for doing this is a scenario like this:
18088 void f(const T&, int i);
18090 void g() { f(3, 7); }
18093 void f(const T& t, const int i) { }
18095 Note that when the template is first instantiated, with
18096 instantiate_template, the resulting DECL will have no name for the
18097 first parameter, and the wrong type for the second. So, when we go
18098 to instantiate the DECL, we regenerate it. */
18101 regenerate_decl_from_template (tree decl, tree tmpl)
18103 /* The arguments used to instantiate DECL, from the most general
18108 args = DECL_TI_ARGS (decl);
18109 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18111 /* Make sure that we can see identifiers, and compute access
18113 push_access_scope (decl);
18115 if (TREE_CODE (decl) == FUNCTION_DECL)
18123 args_depth = TMPL_ARGS_DEPTH (args);
18124 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18125 if (args_depth > parms_depth)
18126 args = get_innermost_template_args (args, parms_depth);
18128 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18129 args, tf_error, NULL_TREE,
18130 /*defer_ok*/false);
18131 if (specs && specs != error_mark_node)
18132 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18135 /* Merge parameter declarations. */
18136 decl_parm = skip_artificial_parms_for (decl,
18137 DECL_ARGUMENTS (decl));
18139 = skip_artificial_parms_for (code_pattern,
18140 DECL_ARGUMENTS (code_pattern));
18141 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18146 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18147 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18148 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18150 parm_type = type_decays_to (parm_type);
18151 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18152 TREE_TYPE (decl_parm) = parm_type;
18153 attributes = DECL_ATTRIBUTES (pattern_parm);
18154 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18156 DECL_ATTRIBUTES (decl_parm) = attributes;
18157 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18159 decl_parm = DECL_CHAIN (decl_parm);
18160 pattern_parm = DECL_CHAIN (pattern_parm);
18162 /* Merge any parameters that match with the function parameter
18164 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18167 tree expanded_types;
18168 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18169 the parameters in this function parameter pack. */
18170 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18171 args, tf_error, NULL_TREE);
18172 len = TREE_VEC_LENGTH (expanded_types);
18173 for (i = 0; i < len; i++)
18178 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18179 /* Rename the parameter to include the index. */
18180 DECL_NAME (decl_parm) =
18181 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18182 parm_type = TREE_VEC_ELT (expanded_types, i);
18183 parm_type = type_decays_to (parm_type);
18184 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18185 TREE_TYPE (decl_parm) = parm_type;
18186 attributes = DECL_ATTRIBUTES (pattern_parm);
18187 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18189 DECL_ATTRIBUTES (decl_parm) = attributes;
18190 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18192 decl_parm = DECL_CHAIN (decl_parm);
18195 /* Merge additional specifiers from the CODE_PATTERN. */
18196 if (DECL_DECLARED_INLINE_P (code_pattern)
18197 && !DECL_DECLARED_INLINE_P (decl))
18198 DECL_DECLARED_INLINE_P (decl) = 1;
18200 else if (TREE_CODE (decl) == VAR_DECL)
18202 DECL_INITIAL (decl) =
18203 tsubst_expr (DECL_INITIAL (code_pattern), args,
18204 tf_error, DECL_TI_TEMPLATE (decl),
18205 /*integral_constant_expression_p=*/false);
18206 if (VAR_HAD_UNKNOWN_BOUND (decl))
18207 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18208 tf_error, DECL_TI_TEMPLATE (decl));
18211 gcc_unreachable ();
18213 pop_access_scope (decl);
18216 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18217 substituted to get DECL. */
18220 template_for_substitution (tree decl)
18222 tree tmpl = DECL_TI_TEMPLATE (decl);
18224 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18225 for the instantiation. This is not always the most general
18226 template. Consider, for example:
18229 struct S { template <class U> void f();
18230 template <> void f<int>(); };
18232 and an instantiation of S<double>::f<int>. We want TD to be the
18233 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18234 while (/* An instantiation cannot have a definition, so we need a
18235 more general template. */
18236 DECL_TEMPLATE_INSTANTIATION (tmpl)
18237 /* We must also deal with friend templates. Given:
18239 template <class T> struct S {
18240 template <class U> friend void f() {};
18243 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18244 so far as the language is concerned, but that's still
18245 where we get the pattern for the instantiation from. On
18246 other hand, if the definition comes outside the class, say:
18248 template <class T> struct S {
18249 template <class U> friend void f();
18251 template <class U> friend void f() {}
18253 we don't need to look any further. That's what the check for
18254 DECL_INITIAL is for. */
18255 || (TREE_CODE (decl) == FUNCTION_DECL
18256 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18257 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18259 /* The present template, TD, should not be a definition. If it
18260 were a definition, we should be using it! Note that we
18261 cannot restructure the loop to just keep going until we find
18262 a template with a definition, since that might go too far if
18263 a specialization was declared, but not defined. */
18264 gcc_assert (TREE_CODE (decl) != VAR_DECL
18265 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18267 /* Fetch the more general template. */
18268 tmpl = DECL_TI_TEMPLATE (tmpl);
18274 /* Returns true if we need to instantiate this template instance even if we
18275 know we aren't going to emit it.. */
18278 always_instantiate_p (tree decl)
18280 /* We always instantiate inline functions so that we can inline them. An
18281 explicit instantiation declaration prohibits implicit instantiation of
18282 non-inline functions. With high levels of optimization, we would
18283 normally inline non-inline functions -- but we're not allowed to do
18284 that for "extern template" functions. Therefore, we check
18285 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18286 return ((TREE_CODE (decl) == FUNCTION_DECL
18287 && DECL_DECLARED_INLINE_P (decl))
18288 /* And we need to instantiate static data members so that
18289 their initializers are available in integral constant
18291 || (TREE_CODE (decl) == VAR_DECL
18292 && decl_maybe_constant_var_p (decl)));
18295 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18296 instantiate it now, modifying TREE_TYPE (fn). */
18299 maybe_instantiate_noexcept (tree fn)
18301 tree fntype, spec, noex, clone;
18303 if (DECL_CLONED_FUNCTION_P (fn))
18304 fn = DECL_CLONED_FUNCTION (fn);
18305 fntype = TREE_TYPE (fn);
18306 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18308 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18311 noex = TREE_PURPOSE (spec);
18313 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18315 if (push_tinst_level (fn))
18317 push_access_scope (fn);
18318 input_location = DECL_SOURCE_LOCATION (fn);
18319 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18320 DEFERRED_NOEXCEPT_ARGS (noex),
18321 tf_warning_or_error, fn,
18322 /*function_p=*/false,
18323 /*integral_constant_expression_p=*/true);
18324 pop_access_scope (fn);
18325 pop_tinst_level ();
18326 spec = build_noexcept_spec (noex, tf_warning_or_error);
18327 if (spec == error_mark_node)
18328 spec = noexcept_false_spec;
18331 spec = noexcept_false_spec;
18335 /* This is an implicitly declared function, so NOEX is a list of
18336 other functions to evaluate and merge. */
18338 spec = noexcept_true_spec;
18339 for (elt = noex; elt; elt = OVL_NEXT (elt))
18341 tree fn = OVL_CURRENT (elt);
18343 maybe_instantiate_noexcept (fn);
18344 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18345 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18349 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18351 FOR_EACH_CLONE (clone, fn)
18353 if (TREE_TYPE (clone) == fntype)
18354 TREE_TYPE (clone) = TREE_TYPE (fn);
18356 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18360 /* Produce the definition of D, a _DECL generated from a template. If
18361 DEFER_OK is nonzero, then we don't have to actually do the
18362 instantiation now; we just have to do it sometime. Normally it is
18363 an error if this is an explicit instantiation but D is undefined.
18364 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18365 explicitly instantiated class template. */
18368 instantiate_decl (tree d, int defer_ok,
18369 bool expl_inst_class_mem_p)
18371 tree tmpl = DECL_TI_TEMPLATE (d);
18378 bool pattern_defined;
18380 location_t saved_loc = input_location;
18383 /* This function should only be used to instantiate templates for
18384 functions and static member variables. */
18385 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18386 || TREE_CODE (d) == VAR_DECL);
18388 /* Variables are never deferred; if instantiation is required, they
18389 are instantiated right away. That allows for better code in the
18390 case that an expression refers to the value of the variable --
18391 if the variable has a constant value the referring expression can
18392 take advantage of that fact. */
18393 if (TREE_CODE (d) == VAR_DECL
18394 || DECL_DECLARED_CONSTEXPR_P (d))
18397 /* Don't instantiate cloned functions. Instead, instantiate the
18398 functions they cloned. */
18399 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18400 d = DECL_CLONED_FUNCTION (d);
18402 if (DECL_TEMPLATE_INSTANTIATED (d)
18403 || (TREE_CODE (d) == FUNCTION_DECL
18404 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18405 || DECL_TEMPLATE_SPECIALIZATION (d))
18406 /* D has already been instantiated or explicitly specialized, so
18407 there's nothing for us to do here.
18409 It might seem reasonable to check whether or not D is an explicit
18410 instantiation, and, if so, stop here. But when an explicit
18411 instantiation is deferred until the end of the compilation,
18412 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18413 the instantiation. */
18416 /* Check to see whether we know that this template will be
18417 instantiated in some other file, as with "extern template"
18419 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18421 /* In general, we do not instantiate such templates. */
18422 if (external_p && !always_instantiate_p (d))
18425 gen_tmpl = most_general_template (tmpl);
18426 gen_args = DECL_TI_ARGS (d);
18428 if (tmpl != gen_tmpl)
18429 /* We should already have the extra args. */
18430 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18431 == TMPL_ARGS_DEPTH (gen_args));
18432 /* And what's in the hash table should match D. */
18433 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18434 || spec == NULL_TREE);
18436 /* This needs to happen before any tsubsting. */
18437 if (! push_tinst_level (d))
18440 timevar_push (TV_TEMPLATE_INST);
18442 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18443 for the instantiation. */
18444 td = template_for_substitution (d);
18445 code_pattern = DECL_TEMPLATE_RESULT (td);
18447 /* We should never be trying to instantiate a member of a class
18448 template or partial specialization. */
18449 gcc_assert (d != code_pattern);
18451 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18452 || DECL_TEMPLATE_SPECIALIZATION (td))
18453 /* In the case of a friend template whose definition is provided
18454 outside the class, we may have too many arguments. Drop the
18455 ones we don't need. The same is true for specializations. */
18456 args = get_innermost_template_args
18457 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18461 if (TREE_CODE (d) == FUNCTION_DECL)
18462 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18463 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18465 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18467 /* We may be in the middle of deferred access check. Disable it now. */
18468 push_deferring_access_checks (dk_no_deferred);
18470 /* Unless an explicit instantiation directive has already determined
18471 the linkage of D, remember that a definition is available for
18473 if (pattern_defined
18474 && !DECL_INTERFACE_KNOWN (d)
18475 && !DECL_NOT_REALLY_EXTERN (d))
18476 mark_definable (d);
18478 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18479 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18480 input_location = DECL_SOURCE_LOCATION (d);
18482 /* If D is a member of an explicitly instantiated class template,
18483 and no definition is available, treat it like an implicit
18485 if (!pattern_defined && expl_inst_class_mem_p
18486 && DECL_EXPLICIT_INSTANTIATION (d))
18488 /* Leave linkage flags alone on instantiations with anonymous
18490 if (TREE_PUBLIC (d))
18492 DECL_NOT_REALLY_EXTERN (d) = 0;
18493 DECL_INTERFACE_KNOWN (d) = 0;
18495 SET_DECL_IMPLICIT_INSTANTIATION (d);
18498 if (TREE_CODE (d) == FUNCTION_DECL)
18499 maybe_instantiate_noexcept (d);
18501 /* Recheck the substitutions to obtain any warning messages
18502 about ignoring cv qualifiers. Don't do this for artificial decls,
18503 as it breaks the context-sensitive substitution for lambda op(). */
18504 if (!defer_ok && !DECL_ARTIFICIAL (d))
18506 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18507 tree type = TREE_TYPE (gen);
18509 /* Make sure that we can see identifiers, and compute access
18510 correctly. D is already the target FUNCTION_DECL with the
18512 push_access_scope (d);
18514 if (TREE_CODE (gen) == FUNCTION_DECL)
18516 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18517 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18518 d, /*defer_ok*/true);
18519 /* Don't simply tsubst the function type, as that will give
18520 duplicate warnings about poor parameter qualifications.
18521 The function arguments are the same as the decl_arguments
18522 without the top level cv qualifiers. */
18523 type = TREE_TYPE (type);
18525 tsubst (type, gen_args, tf_warning_or_error, d);
18527 pop_access_scope (d);
18530 /* Defer all other templates, unless we have been explicitly
18531 forbidden from doing so. */
18532 if (/* If there is no definition, we cannot instantiate the
18535 /* If it's OK to postpone instantiation, do so. */
18537 /* If this is a static data member that will be defined
18538 elsewhere, we don't want to instantiate the entire data
18539 member, but we do want to instantiate the initializer so that
18540 we can substitute that elsewhere. */
18541 || (external_p && TREE_CODE (d) == VAR_DECL))
18543 /* The definition of the static data member is now required so
18544 we must substitute the initializer. */
18545 if (TREE_CODE (d) == VAR_DECL
18546 && !DECL_INITIAL (d)
18547 && DECL_INITIAL (code_pattern))
18551 bool const_init = false;
18553 ns = decl_namespace_context (d);
18554 push_nested_namespace (ns);
18555 push_nested_class (DECL_CONTEXT (d));
18556 init = tsubst_expr (DECL_INITIAL (code_pattern),
18558 tf_warning_or_error, NULL_TREE,
18559 /*integral_constant_expression_p=*/false);
18560 /* Make sure the initializer is still constant, in case of
18561 circular dependency (template/instantiate6.C). */
18563 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18564 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18565 /*asmspec_tree=*/NULL_TREE,
18566 LOOKUP_ONLYCONVERTING);
18567 pop_nested_class ();
18568 pop_nested_namespace (ns);
18571 /* We restore the source position here because it's used by
18572 add_pending_template. */
18573 input_location = saved_loc;
18575 if (at_eof && !pattern_defined
18576 && DECL_EXPLICIT_INSTANTIATION (d)
18577 && DECL_NOT_REALLY_EXTERN (d))
18580 The definition of a non-exported function template, a
18581 non-exported member function template, or a non-exported
18582 member function or static data member of a class template
18583 shall be present in every translation unit in which it is
18584 explicitly instantiated. */
18585 permerror (input_location, "explicit instantiation of %qD "
18586 "but no definition available", d);
18588 /* If we're in unevaluated context, we just wanted to get the
18589 constant value; this isn't an odr use, so don't queue
18590 a full instantiation. */
18591 if (cp_unevaluated_operand != 0)
18593 /* ??? Historically, we have instantiated inline functions, even
18594 when marked as "extern template". */
18595 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18596 add_pending_template (d);
18599 /* Tell the repository that D is available in this translation unit
18600 -- and see if it is supposed to be instantiated here. */
18601 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18603 /* In a PCH file, despite the fact that the repository hasn't
18604 requested instantiation in the PCH it is still possible that
18605 an instantiation will be required in a file that includes the
18608 add_pending_template (d);
18609 /* Instantiate inline functions so that the inliner can do its
18610 job, even though we'll not be emitting a copy of this
18612 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18616 need_push = !cfun || !global_bindings_p ();
18618 push_to_top_level ();
18620 /* Mark D as instantiated so that recursive calls to
18621 instantiate_decl do not try to instantiate it again. */
18622 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18624 /* Regenerate the declaration in case the template has been modified
18625 by a subsequent redeclaration. */
18626 regenerate_decl_from_template (d, td);
18628 /* We already set the file and line above. Reset them now in case
18629 they changed as a result of calling regenerate_decl_from_template. */
18630 input_location = DECL_SOURCE_LOCATION (d);
18632 if (TREE_CODE (d) == VAR_DECL)
18635 bool const_init = false;
18637 /* Clear out DECL_RTL; whatever was there before may not be right
18638 since we've reset the type of the declaration. */
18639 SET_DECL_RTL (d, NULL);
18640 DECL_IN_AGGR_P (d) = 0;
18642 /* The initializer is placed in DECL_INITIAL by
18643 regenerate_decl_from_template so we don't need to
18644 push/pop_access_scope again here. Pull it out so that
18645 cp_finish_decl can process it. */
18646 init = DECL_INITIAL (d);
18647 DECL_INITIAL (d) = NULL_TREE;
18648 DECL_INITIALIZED_P (d) = 0;
18650 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18651 initializer. That function will defer actual emission until
18652 we have a chance to determine linkage. */
18653 DECL_EXTERNAL (d) = 0;
18655 /* Enter the scope of D so that access-checking works correctly. */
18656 push_nested_class (DECL_CONTEXT (d));
18657 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18658 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18659 pop_nested_class ();
18661 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18662 synthesize_method (d);
18663 else if (TREE_CODE (d) == FUNCTION_DECL)
18665 htab_t saved_local_specializations;
18670 /* Save away the current list, in case we are instantiating one
18671 template from within the body of another. */
18672 saved_local_specializations = local_specializations;
18674 /* Set up the list of local specializations. */
18675 local_specializations = htab_create (37,
18676 hash_local_specialization,
18677 eq_local_specializations,
18680 /* Set up context. */
18681 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18683 /* Create substitution entries for the parameters. */
18684 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18685 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18686 spec_parm = DECL_ARGUMENTS (d);
18687 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18689 register_local_specialization (spec_parm, tmpl_parm);
18690 spec_parm = skip_artificial_parms_for (d, spec_parm);
18691 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18693 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18695 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18697 register_local_specialization (spec_parm, tmpl_parm);
18698 spec_parm = DECL_CHAIN (spec_parm);
18702 /* Register the (value) argument pack as a specialization of
18703 TMPL_PARM, then move on. */
18704 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18705 register_local_specialization (argpack, tmpl_parm);
18708 gcc_assert (!spec_parm);
18710 /* Substitute into the body of the function. */
18711 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18712 tf_warning_or_error, tmpl,
18713 /*integral_constant_expression_p=*/false);
18715 /* Set the current input_location to the end of the function
18716 so that finish_function knows where we are. */
18717 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18719 /* We don't need the local specializations any more. */
18720 htab_delete (local_specializations);
18721 local_specializations = saved_local_specializations;
18723 /* Finish the function. */
18724 d = finish_function (0);
18725 expand_or_defer_fn (d);
18728 /* We're not deferring instantiation any more. */
18729 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18732 pop_from_top_level ();
18735 input_location = saved_loc;
18736 pop_deferring_access_checks ();
18737 pop_tinst_level ();
18739 timevar_pop (TV_TEMPLATE_INST);
18744 /* Run through the list of templates that we wish we could
18745 instantiate, and instantiate any we can. RETRIES is the
18746 number of times we retry pending template instantiation. */
18749 instantiate_pending_templates (int retries)
18752 location_t saved_loc = input_location;
18754 /* Instantiating templates may trigger vtable generation. This in turn
18755 may require further template instantiations. We place a limit here
18756 to avoid infinite loop. */
18757 if (pending_templates && retries >= max_tinst_depth)
18759 tree decl = pending_templates->tinst->decl;
18761 error ("template instantiation depth exceeds maximum of %d"
18762 " instantiating %q+D, possibly from virtual table generation"
18763 " (use -ftemplate-depth= to increase the maximum)",
18764 max_tinst_depth, decl);
18765 if (TREE_CODE (decl) == FUNCTION_DECL)
18766 /* Pretend that we defined it. */
18767 DECL_INITIAL (decl) = error_mark_node;
18773 struct pending_template **t = &pending_templates;
18774 struct pending_template *last = NULL;
18778 tree instantiation = reopen_tinst_level ((*t)->tinst);
18779 bool complete = false;
18781 if (TYPE_P (instantiation))
18785 if (!COMPLETE_TYPE_P (instantiation))
18787 instantiate_class_template (instantiation);
18788 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18789 for (fn = TYPE_METHODS (instantiation);
18791 fn = TREE_CHAIN (fn))
18792 if (! DECL_ARTIFICIAL (fn))
18793 instantiate_decl (fn,
18795 /*expl_inst_class_mem_p=*/false);
18796 if (COMPLETE_TYPE_P (instantiation))
18800 complete = COMPLETE_TYPE_P (instantiation);
18804 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18805 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18808 = instantiate_decl (instantiation,
18810 /*expl_inst_class_mem_p=*/false);
18811 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18815 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18816 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18820 /* If INSTANTIATION has been instantiated, then we don't
18821 need to consider it again in the future. */
18829 current_tinst_level = NULL;
18831 last_pending_template = last;
18833 while (reconsider);
18835 input_location = saved_loc;
18838 /* Substitute ARGVEC into T, which is a list of initializers for
18839 either base class or a non-static data member. The TREE_PURPOSEs
18840 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18841 instantiate_decl. */
18844 tsubst_initializer_list (tree t, tree argvec)
18846 tree inits = NULL_TREE;
18848 for (; t; t = TREE_CHAIN (t))
18852 tree expanded_bases = NULL_TREE;
18853 tree expanded_arguments = NULL_TREE;
18856 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18861 /* Expand the base class expansion type into separate base
18863 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18864 tf_warning_or_error,
18866 if (expanded_bases == error_mark_node)
18869 /* We'll be building separate TREE_LISTs of arguments for
18871 len = TREE_VEC_LENGTH (expanded_bases);
18872 expanded_arguments = make_tree_vec (len);
18873 for (i = 0; i < len; i++)
18874 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18876 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18877 expand each argument in the TREE_VALUE of t. */
18878 expr = make_node (EXPR_PACK_EXPANSION);
18879 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18880 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18882 if (TREE_VALUE (t) == void_type_node)
18883 /* VOID_TYPE_NODE is used to indicate
18884 value-initialization. */
18886 for (i = 0; i < len; i++)
18887 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18891 /* Substitute parameter packs into each argument in the
18893 in_base_initializer = 1;
18894 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18896 tree expanded_exprs;
18898 /* Expand the argument. */
18899 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18901 = tsubst_pack_expansion (expr, argvec,
18902 tf_warning_or_error,
18904 if (expanded_exprs == error_mark_node)
18907 /* Prepend each of the expanded expressions to the
18908 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18909 for (i = 0; i < len; i++)
18911 TREE_VEC_ELT (expanded_arguments, i) =
18912 tree_cons (NULL_TREE,
18913 TREE_VEC_ELT (expanded_exprs, i),
18914 TREE_VEC_ELT (expanded_arguments, i));
18917 in_base_initializer = 0;
18919 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18920 since we built them backwards. */
18921 for (i = 0; i < len; i++)
18923 TREE_VEC_ELT (expanded_arguments, i) =
18924 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18929 for (i = 0; i < len; ++i)
18931 if (expanded_bases)
18933 decl = TREE_VEC_ELT (expanded_bases, i);
18934 decl = expand_member_init (decl);
18935 init = TREE_VEC_ELT (expanded_arguments, i);
18939 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18940 tf_warning_or_error, NULL_TREE);
18942 decl = expand_member_init (decl);
18943 if (decl && !DECL_P (decl))
18944 in_base_initializer = 1;
18946 init = TREE_VALUE (t);
18947 if (init != void_type_node)
18948 init = tsubst_expr (init, argvec,
18949 tf_warning_or_error, NULL_TREE,
18950 /*integral_constant_expression_p=*/false);
18951 in_base_initializer = 0;
18956 init = build_tree_list (decl, init);
18957 TREE_CHAIN (init) = inits;
18965 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18968 set_current_access_from_decl (tree decl)
18970 if (TREE_PRIVATE (decl))
18971 current_access_specifier = access_private_node;
18972 else if (TREE_PROTECTED (decl))
18973 current_access_specifier = access_protected_node;
18975 current_access_specifier = access_public_node;
18978 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18979 is the instantiation (which should have been created with
18980 start_enum) and ARGS are the template arguments to use. */
18983 tsubst_enum (tree tag, tree newtag, tree args)
18987 if (SCOPED_ENUM_P (newtag))
18988 begin_scope (sk_scoped_enum, newtag);
18990 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18995 decl = TREE_VALUE (e);
18996 /* Note that in a template enum, the TREE_VALUE is the
18997 CONST_DECL, not the corresponding INTEGER_CST. */
18998 value = tsubst_expr (DECL_INITIAL (decl),
18999 args, tf_warning_or_error, NULL_TREE,
19000 /*integral_constant_expression_p=*/true);
19002 /* Give this enumeration constant the correct access. */
19003 set_current_access_from_decl (decl);
19005 /* Actually build the enumerator itself. */
19007 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19010 if (SCOPED_ENUM_P (newtag))
19013 finish_enum_value_list (newtag);
19014 finish_enum (newtag);
19016 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19017 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19020 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19021 its type -- but without substituting the innermost set of template
19022 arguments. So, innermost set of template parameters will appear in
19026 get_mostly_instantiated_function_type (tree decl)
19034 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19035 targs = DECL_TI_ARGS (decl);
19036 tparms = DECL_TEMPLATE_PARMS (tmpl);
19037 parm_depth = TMPL_PARMS_DEPTH (tparms);
19039 /* There should be as many levels of arguments as there are levels
19041 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19043 fn_type = TREE_TYPE (tmpl);
19045 if (parm_depth == 1)
19046 /* No substitution is necessary. */
19053 /* Replace the innermost level of the TARGS with NULL_TREEs to
19054 let tsubst know not to substitute for those parameters. */
19055 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19056 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19057 SET_TMPL_ARGS_LEVEL (partial_args, i,
19058 TMPL_ARGS_LEVEL (targs, i));
19059 SET_TMPL_ARGS_LEVEL (partial_args,
19060 TMPL_ARGS_DEPTH (targs),
19061 make_tree_vec (DECL_NTPARMS (tmpl)));
19063 /* Make sure that we can see identifiers, and compute access
19065 push_access_scope (decl);
19067 ++processing_template_decl;
19068 /* Now, do the (partial) substitution to figure out the
19069 appropriate function type. */
19070 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19071 --processing_template_decl;
19073 /* Substitute into the template parameters to obtain the real
19074 innermost set of parameters. This step is important if the
19075 innermost set of template parameters contains value
19076 parameters whose types depend on outer template parameters. */
19077 TREE_VEC_LENGTH (partial_args)--;
19078 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19080 pop_access_scope (decl);
19086 /* Return truthvalue if we're processing a template different from
19087 the last one involved in diagnostics. */
19089 problematic_instantiation_changed (void)
19091 return current_tinst_level != last_error_tinst_level;
19094 /* Remember current template involved in diagnostics. */
19096 record_last_problematic_instantiation (void)
19098 last_error_tinst_level = current_tinst_level;
19101 struct tinst_level *
19102 current_instantiation (void)
19104 return current_tinst_level;
19107 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19108 type. Return zero for ok, nonzero for disallowed. Issue error and
19109 warning messages under control of COMPLAIN. */
19112 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19114 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19116 else if (POINTER_TYPE_P (type))
19118 else if (TYPE_PTR_TO_MEMBER_P (type))
19120 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19122 else if (TREE_CODE (type) == TYPENAME_TYPE)
19124 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19126 else if (TREE_CODE (type) == NULLPTR_TYPE)
19129 if (complain & tf_error)
19131 if (type == error_mark_node)
19132 inform (input_location, "invalid template non-type parameter");
19134 error ("%q#T is not a valid type for a template non-type parameter",
19140 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19141 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19144 dependent_type_p_r (tree type)
19150 A type is dependent if it is:
19152 -- a template parameter. Template template parameters are types
19153 for us (since TYPE_P holds true for them) so we handle
19155 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19156 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19158 /* -- a qualified-id with a nested-name-specifier which contains a
19159 class-name that names a dependent type or whose unqualified-id
19160 names a dependent type. */
19161 if (TREE_CODE (type) == TYPENAME_TYPE)
19163 /* -- a cv-qualified type where the cv-unqualified type is
19165 type = TYPE_MAIN_VARIANT (type);
19166 /* -- a compound type constructed from any dependent type. */
19167 if (TYPE_PTR_TO_MEMBER_P (type))
19168 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19169 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19171 else if (TREE_CODE (type) == POINTER_TYPE
19172 || TREE_CODE (type) == REFERENCE_TYPE)
19173 return dependent_type_p (TREE_TYPE (type));
19174 else if (TREE_CODE (type) == FUNCTION_TYPE
19175 || TREE_CODE (type) == METHOD_TYPE)
19179 if (dependent_type_p (TREE_TYPE (type)))
19181 for (arg_type = TYPE_ARG_TYPES (type);
19183 arg_type = TREE_CHAIN (arg_type))
19184 if (dependent_type_p (TREE_VALUE (arg_type)))
19188 /* -- an array type constructed from any dependent type or whose
19189 size is specified by a constant expression that is
19192 We checked for type- and value-dependence of the bounds in
19193 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19194 if (TREE_CODE (type) == ARRAY_TYPE)
19196 if (TYPE_DOMAIN (type)
19197 && dependent_type_p (TYPE_DOMAIN (type)))
19199 return dependent_type_p (TREE_TYPE (type));
19202 /* -- a template-id in which either the template name is a template
19204 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19206 /* ... or any of the template arguments is a dependent type or
19207 an expression that is type-dependent or value-dependent. */
19208 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19209 && (any_dependent_template_arguments_p
19210 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19213 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19214 dependent; if the argument of the `typeof' expression is not
19215 type-dependent, then it should already been have resolved. */
19216 if (TREE_CODE (type) == TYPEOF_TYPE
19217 || TREE_CODE (type) == DECLTYPE_TYPE
19218 || TREE_CODE (type) == UNDERLYING_TYPE)
19221 /* A template argument pack is dependent if any of its packed
19223 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19225 tree args = ARGUMENT_PACK_ARGS (type);
19226 int i, len = TREE_VEC_LENGTH (args);
19227 for (i = 0; i < len; ++i)
19228 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19232 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19233 be template parameters. */
19234 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19237 /* The standard does not specifically mention types that are local
19238 to template functions or local classes, but they should be
19239 considered dependent too. For example:
19241 template <int I> void f() {
19246 The size of `E' cannot be known until the value of `I' has been
19247 determined. Therefore, `E' must be considered dependent. */
19248 scope = TYPE_CONTEXT (type);
19249 if (scope && TYPE_P (scope))
19250 return dependent_type_p (scope);
19251 /* Don't use type_dependent_expression_p here, as it can lead
19252 to infinite recursion trying to determine whether a lambda
19253 nested in a lambda is dependent (c++/47687). */
19254 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19255 && DECL_LANG_SPECIFIC (scope)
19256 && DECL_TEMPLATE_INFO (scope)
19257 && (any_dependent_template_arguments_p
19258 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19261 /* Other types are non-dependent. */
19265 /* Returns TRUE if TYPE is dependent, in the sense of
19266 [temp.dep.type]. Note that a NULL type is considered dependent. */
19269 dependent_type_p (tree type)
19271 /* If there are no template parameters in scope, then there can't be
19272 any dependent types. */
19273 if (!processing_template_decl)
19275 /* If we are not processing a template, then nobody should be
19276 providing us with a dependent type. */
19278 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19282 /* If the type is NULL, we have not computed a type for the entity
19283 in question; in that case, the type is dependent. */
19287 /* Erroneous types can be considered non-dependent. */
19288 if (type == error_mark_node)
19291 /* If we have not already computed the appropriate value for TYPE,
19293 if (!TYPE_DEPENDENT_P_VALID (type))
19295 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19296 TYPE_DEPENDENT_P_VALID (type) = 1;
19299 return TYPE_DEPENDENT_P (type);
19302 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19303 lookup. In other words, a dependent type that is not the current
19307 dependent_scope_p (tree scope)
19309 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19310 && !currently_open_class (scope));
19313 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19314 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19317 /* Note that this predicate is not appropriate for general expressions;
19318 only constant expressions (that satisfy potential_constant_expression)
19319 can be tested for value dependence.
19321 We should really also have a predicate for "instantiation-dependent".
19323 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19324 (what about instantiation-dependent constant-expressions?)
19325 is_late_template_attribute: defer if instantiation-dependent.
19326 compute_array_index_type: proceed if constant and not t- or v-dependent
19327 if instantiation-dependent, need to remember full expression
19328 uses_template_parms: FIXME - need to audit callers
19329 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19330 dependent_type_p [array_type]: dependent if index type is dependent
19332 static_assert - instantiation-dependent */
19335 value_dependent_expression_p (tree expression)
19337 if (!processing_template_decl)
19340 /* A name declared with a dependent type. */
19341 if (DECL_P (expression) && type_dependent_expression_p (expression))
19344 switch (TREE_CODE (expression))
19346 case IDENTIFIER_NODE:
19347 /* A name that has not been looked up -- must be dependent. */
19350 case TEMPLATE_PARM_INDEX:
19351 /* A non-type template parm. */
19355 /* A non-type template parm. */
19356 if (DECL_TEMPLATE_PARM_P (expression))
19358 return value_dependent_expression_p (DECL_INITIAL (expression));
19361 /* A constant with literal type and is initialized
19362 with an expression that is value-dependent. */
19363 if (DECL_INITIAL (expression)
19364 && decl_constant_var_p (expression)
19365 && value_dependent_expression_p (DECL_INITIAL (expression)))
19369 case DYNAMIC_CAST_EXPR:
19370 case STATIC_CAST_EXPR:
19371 case CONST_CAST_EXPR:
19372 case REINTERPRET_CAST_EXPR:
19374 /* These expressions are value-dependent if the type to which
19375 the cast occurs is dependent or the expression being casted
19376 is value-dependent. */
19378 tree type = TREE_TYPE (expression);
19380 if (dependent_type_p (type))
19383 /* A functional cast has a list of operands. */
19384 expression = TREE_OPERAND (expression, 0);
19387 /* If there are no operands, it must be an expression such
19388 as "int()". This should not happen for aggregate types
19389 because it would form non-constant expressions. */
19390 gcc_assert (cxx_dialect >= cxx0x
19391 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19396 if (TREE_CODE (expression) == TREE_LIST)
19397 return any_value_dependent_elements_p (expression);
19399 return value_dependent_expression_p (expression);
19405 /* A `sizeof' expression is value-dependent if the operand is
19406 type-dependent or is a pack expansion. */
19407 expression = TREE_OPERAND (expression, 0);
19408 if (PACK_EXPANSION_P (expression))
19410 else if (TYPE_P (expression))
19411 return dependent_type_p (expression);
19412 return type_dependent_expression_p (expression);
19414 case AT_ENCODE_EXPR:
19415 /* An 'encode' expression is value-dependent if the operand is
19417 expression = TREE_OPERAND (expression, 0);
19418 return dependent_type_p (expression);
19420 case NOEXCEPT_EXPR:
19421 expression = TREE_OPERAND (expression, 0);
19422 return type_dependent_expression_p (expression);
19426 tree name = TREE_OPERAND (expression, 1);
19427 return value_dependent_expression_p (name);
19430 case COMPONENT_REF:
19431 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19432 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19434 case NONTYPE_ARGUMENT_PACK:
19435 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19436 is value-dependent. */
19438 tree values = ARGUMENT_PACK_ARGS (expression);
19439 int i, len = TREE_VEC_LENGTH (values);
19441 for (i = 0; i < len; ++i)
19442 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19450 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19451 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19452 || (type2 ? dependent_type_p (type2) : false));
19456 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19457 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19460 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19461 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19465 tree op = TREE_OPERAND (expression, 0);
19466 return (value_dependent_expression_p (op)
19467 || has_value_dependent_address (op));
19472 tree fn = get_callee_fndecl (expression);
19474 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19476 nargs = call_expr_nargs (expression);
19477 for (i = 0; i < nargs; ++i)
19479 tree op = CALL_EXPR_ARG (expression, i);
19480 /* In a call to a constexpr member function, look through the
19481 implicit ADDR_EXPR on the object argument so that it doesn't
19482 cause the call to be considered value-dependent. We also
19483 look through it in potential_constant_expression. */
19484 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19485 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19486 && TREE_CODE (op) == ADDR_EXPR)
19487 op = TREE_OPERAND (op, 0);
19488 if (value_dependent_expression_p (op))
19494 case TEMPLATE_ID_EXPR:
19495 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19497 return type_dependent_expression_p (expression);
19503 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19504 if (value_dependent_expression_p (val))
19510 /* A constant expression is value-dependent if any subexpression is
19511 value-dependent. */
19512 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19514 case tcc_reference:
19516 case tcc_comparison:
19518 case tcc_expression:
19521 int i, len = cp_tree_operand_length (expression);
19523 for (i = 0; i < len; i++)
19525 tree t = TREE_OPERAND (expression, i);
19527 /* In some cases, some of the operands may be missing.l
19528 (For example, in the case of PREDECREMENT_EXPR, the
19529 amount to increment by may be missing.) That doesn't
19530 make the expression dependent. */
19531 if (t && value_dependent_expression_p (t))
19542 /* The expression is not value-dependent. */
19546 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19547 [temp.dep.expr]. Note that an expression with no type is
19548 considered dependent. Other parts of the compiler arrange for an
19549 expression with type-dependent subexpressions to have no type, so
19550 this function doesn't have to be fully recursive. */
19553 type_dependent_expression_p (tree expression)
19555 if (!processing_template_decl)
19558 if (expression == error_mark_node)
19561 /* An unresolved name is always dependent. */
19562 if (TREE_CODE (expression) == IDENTIFIER_NODE
19563 || TREE_CODE (expression) == USING_DECL)
19566 /* Some expression forms are never type-dependent. */
19567 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19568 || TREE_CODE (expression) == SIZEOF_EXPR
19569 || TREE_CODE (expression) == ALIGNOF_EXPR
19570 || TREE_CODE (expression) == AT_ENCODE_EXPR
19571 || TREE_CODE (expression) == NOEXCEPT_EXPR
19572 || TREE_CODE (expression) == TRAIT_EXPR
19573 || TREE_CODE (expression) == TYPEID_EXPR
19574 || TREE_CODE (expression) == DELETE_EXPR
19575 || TREE_CODE (expression) == VEC_DELETE_EXPR
19576 || TREE_CODE (expression) == THROW_EXPR)
19579 /* The types of these expressions depends only on the type to which
19580 the cast occurs. */
19581 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19582 || TREE_CODE (expression) == STATIC_CAST_EXPR
19583 || TREE_CODE (expression) == CONST_CAST_EXPR
19584 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19585 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19586 || TREE_CODE (expression) == CAST_EXPR)
19587 return dependent_type_p (TREE_TYPE (expression));
19589 /* The types of these expressions depends only on the type created
19590 by the expression. */
19591 if (TREE_CODE (expression) == NEW_EXPR
19592 || TREE_CODE (expression) == VEC_NEW_EXPR)
19594 /* For NEW_EXPR tree nodes created inside a template, either
19595 the object type itself or a TREE_LIST may appear as the
19597 tree type = TREE_OPERAND (expression, 1);
19598 if (TREE_CODE (type) == TREE_LIST)
19599 /* This is an array type. We need to check array dimensions
19601 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19602 || value_dependent_expression_p
19603 (TREE_OPERAND (TREE_VALUE (type), 1));
19605 return dependent_type_p (type);
19608 if (TREE_CODE (expression) == SCOPE_REF)
19610 tree scope = TREE_OPERAND (expression, 0);
19611 tree name = TREE_OPERAND (expression, 1);
19613 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19614 contains an identifier associated by name lookup with one or more
19615 declarations declared with a dependent type, or...a
19616 nested-name-specifier or qualified-id that names a member of an
19617 unknown specialization. */
19618 return (type_dependent_expression_p (name)
19619 || dependent_scope_p (scope));
19622 if (TREE_CODE (expression) == FUNCTION_DECL
19623 && DECL_LANG_SPECIFIC (expression)
19624 && DECL_TEMPLATE_INFO (expression)
19625 && (any_dependent_template_arguments_p
19626 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19629 if (TREE_CODE (expression) == TEMPLATE_DECL
19630 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19633 if (TREE_CODE (expression) == STMT_EXPR)
19634 expression = stmt_expr_value_expr (expression);
19636 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19641 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19643 if (type_dependent_expression_p (elt))
19649 /* A static data member of the current instantiation with incomplete
19650 array type is type-dependent, as the definition and specializations
19651 can have different bounds. */
19652 if (TREE_CODE (expression) == VAR_DECL
19653 && DECL_CLASS_SCOPE_P (expression)
19654 && dependent_type_p (DECL_CONTEXT (expression))
19655 && VAR_HAD_UNKNOWN_BOUND (expression))
19658 if (TREE_TYPE (expression) == unknown_type_node)
19660 if (TREE_CODE (expression) == ADDR_EXPR)
19661 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19662 if (TREE_CODE (expression) == COMPONENT_REF
19663 || TREE_CODE (expression) == OFFSET_REF)
19665 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19667 expression = TREE_OPERAND (expression, 1);
19668 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19671 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19672 if (TREE_CODE (expression) == SCOPE_REF)
19675 if (BASELINK_P (expression))
19676 expression = BASELINK_FUNCTIONS (expression);
19678 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19680 if (any_dependent_template_arguments_p
19681 (TREE_OPERAND (expression, 1)))
19683 expression = TREE_OPERAND (expression, 0);
19685 gcc_assert (TREE_CODE (expression) == OVERLOAD
19686 || TREE_CODE (expression) == FUNCTION_DECL);
19690 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19692 expression = OVL_NEXT (expression);
19697 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19699 return (dependent_type_p (TREE_TYPE (expression)));
19702 /* Like type_dependent_expression_p, but it also works while not processing
19703 a template definition, i.e. during substitution or mangling. */
19706 type_dependent_expression_p_push (tree expr)
19709 ++processing_template_decl;
19710 b = type_dependent_expression_p (expr);
19711 --processing_template_decl;
19715 /* Returns TRUE if ARGS contains a type-dependent expression. */
19718 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19723 FOR_EACH_VEC_ELT (tree, args, i, arg)
19725 if (type_dependent_expression_p (arg))
19731 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19732 expressions) contains any type-dependent expressions. */
19735 any_type_dependent_elements_p (const_tree list)
19737 for (; list; list = TREE_CHAIN (list))
19738 if (value_dependent_expression_p (TREE_VALUE (list)))
19744 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19745 expressions) contains any value-dependent expressions. */
19748 any_value_dependent_elements_p (const_tree list)
19750 for (; list; list = TREE_CHAIN (list))
19751 if (value_dependent_expression_p (TREE_VALUE (list)))
19757 /* Returns TRUE if the ARG (a template argument) is dependent. */
19760 dependent_template_arg_p (tree arg)
19762 if (!processing_template_decl)
19765 /* Assume a template argument that was wrongly written by the user
19766 is dependent. This is consistent with what
19767 any_dependent_template_arguments_p [that calls this function]
19769 if (!arg || arg == error_mark_node)
19772 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19773 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19775 if (TREE_CODE (arg) == TEMPLATE_DECL
19776 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19777 return dependent_template_p (arg);
19778 else if (ARGUMENT_PACK_P (arg))
19780 tree args = ARGUMENT_PACK_ARGS (arg);
19781 int i, len = TREE_VEC_LENGTH (args);
19782 for (i = 0; i < len; ++i)
19784 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19790 else if (TYPE_P (arg))
19791 return dependent_type_p (arg);
19793 return (type_dependent_expression_p (arg)
19794 || value_dependent_expression_p (arg));
19797 /* Returns true if ARGS (a collection of template arguments) contains
19798 any types that require structural equality testing. */
19801 any_template_arguments_need_structural_equality_p (tree args)
19808 if (args == error_mark_node)
19811 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19813 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19814 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19816 tree arg = TREE_VEC_ELT (level, j);
19817 tree packed_args = NULL_TREE;
19820 if (ARGUMENT_PACK_P (arg))
19822 /* Look inside the argument pack. */
19823 packed_args = ARGUMENT_PACK_ARGS (arg);
19824 len = TREE_VEC_LENGTH (packed_args);
19827 for (k = 0; k < len; ++k)
19830 arg = TREE_VEC_ELT (packed_args, k);
19832 if (error_operand_p (arg))
19834 else if (TREE_CODE (arg) == TEMPLATE_DECL
19835 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19837 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19839 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19840 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19849 /* Returns true if ARGS (a collection of template arguments) contains
19850 any dependent arguments. */
19853 any_dependent_template_arguments_p (const_tree args)
19860 if (args == error_mark_node)
19863 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19865 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19866 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19867 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19874 /* Returns TRUE if the template TMPL is dependent. */
19877 dependent_template_p (tree tmpl)
19879 if (TREE_CODE (tmpl) == OVERLOAD)
19883 if (dependent_template_p (OVL_CURRENT (tmpl)))
19885 tmpl = OVL_NEXT (tmpl);
19890 /* Template template parameters are dependent. */
19891 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19892 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19894 /* So are names that have not been looked up. */
19895 if (TREE_CODE (tmpl) == SCOPE_REF
19896 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19898 /* So are member templates of dependent classes. */
19899 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19900 return dependent_type_p (DECL_CONTEXT (tmpl));
19904 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19907 dependent_template_id_p (tree tmpl, tree args)
19909 return (dependent_template_p (tmpl)
19910 || any_dependent_template_arguments_p (args));
19913 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19917 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19921 if (!processing_template_decl)
19924 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19926 tree decl = TREE_VEC_ELT (declv, i);
19927 tree init = TREE_VEC_ELT (initv, i);
19928 tree cond = TREE_VEC_ELT (condv, i);
19929 tree incr = TREE_VEC_ELT (incrv, i);
19931 if (type_dependent_expression_p (decl))
19934 if (init && type_dependent_expression_p (init))
19937 if (type_dependent_expression_p (cond))
19940 if (COMPARISON_CLASS_P (cond)
19941 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19942 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19945 if (TREE_CODE (incr) == MODOP_EXPR)
19947 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19948 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19951 else if (type_dependent_expression_p (incr))
19953 else if (TREE_CODE (incr) == MODIFY_EXPR)
19955 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19957 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19959 tree t = TREE_OPERAND (incr, 1);
19960 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19961 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19970 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19971 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19972 no such TYPE can be found. Note that this function peers inside
19973 uninstantiated templates and therefore should be used only in
19974 extremely limited situations. ONLY_CURRENT_P restricts this
19975 peering to the currently open classes hierarchy (which is required
19976 when comparing types). */
19979 resolve_typename_type (tree type, bool only_current_p)
19988 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19990 scope = TYPE_CONTEXT (type);
19991 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19992 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19993 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19994 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19995 identifier of the TYPENAME_TYPE anymore.
19996 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19997 TYPENAME_TYPE instead, we avoid messing up with a possible
19998 typedef variant case. */
19999 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20001 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20002 it first before we can figure out what NAME refers to. */
20003 if (TREE_CODE (scope) == TYPENAME_TYPE)
20004 scope = resolve_typename_type (scope, only_current_p);
20005 /* If we don't know what SCOPE refers to, then we cannot resolve the
20007 if (TREE_CODE (scope) == TYPENAME_TYPE)
20009 /* If the SCOPE is a template type parameter, we have no way of
20010 resolving the name. */
20011 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20013 /* If the SCOPE is not the current instantiation, there's no reason
20014 to look inside it. */
20015 if (only_current_p && !currently_open_class (scope))
20017 /* If this is a typedef, we don't want to look inside (c++/11987). */
20018 if (typedef_variant_p (type))
20020 /* If SCOPE isn't the template itself, it will not have a valid
20021 TYPE_FIELDS list. */
20022 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20023 /* scope is either the template itself or a compatible instantiation
20024 like X<T>, so look up the name in the original template. */
20025 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20027 /* scope is a partial instantiation, so we can't do the lookup or we
20028 will lose the template arguments. */
20030 /* Enter the SCOPE so that name lookup will be resolved as if we
20031 were in the class definition. In particular, SCOPE will no
20032 longer be considered a dependent type. */
20033 pushed_scope = push_scope (scope);
20034 /* Look up the declaration. */
20035 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20036 tf_warning_or_error);
20038 result = NULL_TREE;
20040 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20041 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20044 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20045 && TREE_CODE (decl) == TYPE_DECL)
20047 result = TREE_TYPE (decl);
20048 if (result == error_mark_node)
20049 result = NULL_TREE;
20051 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20052 && DECL_CLASS_TEMPLATE_P (decl))
20056 /* Obtain the template and the arguments. */
20057 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20058 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20059 /* Instantiate the template. */
20060 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20061 /*entering_scope=*/0,
20062 tf_error | tf_user);
20063 if (result == error_mark_node)
20064 result = NULL_TREE;
20067 /* Leave the SCOPE. */
20069 pop_scope (pushed_scope);
20071 /* If we failed to resolve it, return the original typename. */
20075 /* If lookup found a typename type, resolve that too. */
20076 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20078 /* Ill-formed programs can cause infinite recursion here, so we
20079 must catch that. */
20080 TYPENAME_IS_RESOLVING_P (type) = 1;
20081 result = resolve_typename_type (result, only_current_p);
20082 TYPENAME_IS_RESOLVING_P (type) = 0;
20085 /* Qualify the resulting type. */
20086 quals = cp_type_quals (type);
20088 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20093 /* EXPR is an expression which is not type-dependent. Return a proxy
20094 for EXPR that can be used to compute the types of larger
20095 expressions containing EXPR. */
20098 build_non_dependent_expr (tree expr)
20102 #ifdef ENABLE_CHECKING
20103 /* Try to get a constant value for all non-type-dependent expressions in
20104 order to expose bugs in *_dependent_expression_p and constexpr. */
20105 if (cxx_dialect >= cxx0x)
20106 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20109 /* Preserve OVERLOADs; the functions must be available to resolve
20112 if (TREE_CODE (inner_expr) == STMT_EXPR)
20113 inner_expr = stmt_expr_value_expr (inner_expr);
20114 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20115 inner_expr = TREE_OPERAND (inner_expr, 0);
20116 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20117 inner_expr = TREE_OPERAND (inner_expr, 1);
20118 if (is_overloaded_fn (inner_expr)
20119 || TREE_CODE (inner_expr) == OFFSET_REF)
20121 /* There is no need to return a proxy for a variable. */
20122 if (TREE_CODE (expr) == VAR_DECL)
20124 /* Preserve string constants; conversions from string constants to
20125 "char *" are allowed, even though normally a "const char *"
20126 cannot be used to initialize a "char *". */
20127 if (TREE_CODE (expr) == STRING_CST)
20129 /* Preserve arithmetic constants, as an optimization -- there is no
20130 reason to create a new node. */
20131 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20133 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20134 There is at least one place where we want to know that a
20135 particular expression is a throw-expression: when checking a ?:
20136 expression, there are special rules if the second or third
20137 argument is a throw-expression. */
20138 if (TREE_CODE (expr) == THROW_EXPR)
20141 /* Don't wrap an initializer list, we need to be able to look inside. */
20142 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20145 if (TREE_CODE (expr) == COND_EXPR)
20146 return build3 (COND_EXPR,
20148 TREE_OPERAND (expr, 0),
20149 (TREE_OPERAND (expr, 1)
20150 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20151 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20152 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20153 if (TREE_CODE (expr) == COMPOUND_EXPR
20154 && !COMPOUND_EXPR_OVERLOADED (expr))
20155 return build2 (COMPOUND_EXPR,
20157 TREE_OPERAND (expr, 0),
20158 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20160 /* If the type is unknown, it can't really be non-dependent */
20161 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20163 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20164 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20167 /* ARGS is a vector of expressions as arguments to a function call.
20168 Replace the arguments with equivalent non-dependent expressions.
20169 This modifies ARGS in place. */
20172 make_args_non_dependent (VEC(tree,gc) *args)
20177 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20179 tree newarg = build_non_dependent_expr (arg);
20181 VEC_replace (tree, args, ix, newarg);
20185 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20186 with a level one deeper than the actual template parms. */
20191 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20192 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20193 TYPE_DECL, get_identifier ("auto"), au);
20194 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20195 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20196 (0, processing_template_decl + 1, processing_template_decl + 1,
20197 0, TYPE_NAME (au), NULL_TREE);
20198 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20199 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20200 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20205 /* Given type ARG, return std::initializer_list<ARG>. */
20210 tree std_init_list = namespace_binding
20211 (get_identifier ("initializer_list"), std_node);
20213 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20215 error ("deducing from brace-enclosed initializer list requires "
20216 "#include <initializer_list>");
20217 return error_mark_node;
20219 argvec = make_tree_vec (1);
20220 TREE_VEC_ELT (argvec, 0) = arg;
20221 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20222 NULL_TREE, 0, tf_warning_or_error);
20225 /* Replace auto in TYPE with std::initializer_list<auto>. */
20228 listify_autos (tree type, tree auto_node)
20230 tree init_auto = listify (auto_node);
20231 tree argvec = make_tree_vec (1);
20232 TREE_VEC_ELT (argvec, 0) = init_auto;
20233 if (processing_template_decl)
20234 argvec = add_to_template_args (current_template_args (), argvec);
20235 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20238 /* walk_tree helper for do_auto_deduction. */
20241 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20244 /* Is this a variable with the type we're looking for? */
20246 && TREE_TYPE (*tp) == type)
20252 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20253 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20256 do_auto_deduction (tree type, tree init, tree auto_node)
20258 tree parms, tparms, targs;
20263 if (processing_template_decl
20264 && (TREE_TYPE (init) == NULL_TREE
20265 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20266 /* Not enough information to try this yet. */
20269 /* The name of the object being declared shall not appear in the
20270 initializer expression. */
20271 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20274 error ("variable %q#D with %<auto%> type used in its own "
20275 "initializer", decl);
20276 return error_mark_node;
20279 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20280 with either a new invented type template parameter U or, if the
20281 initializer is a braced-init-list (8.5.4), with
20282 std::initializer_list<U>. */
20283 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20284 type = listify_autos (type, auto_node);
20286 init = resolve_nondeduced_context (init);
20288 parms = build_tree_list (NULL_TREE, type);
20290 tparms = make_tree_vec (1);
20291 targs = make_tree_vec (1);
20292 TREE_VEC_ELT (tparms, 0)
20293 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20294 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20295 DEDUCE_CALL, LOOKUP_NORMAL,
20296 /*explain_p=*/false);
20299 if (processing_template_decl)
20300 /* Try again at instantiation time. */
20302 if (type && type != error_mark_node)
20303 /* If type is error_mark_node a diagnostic must have been
20304 emitted by now. Also, having a mention to '<type error>'
20305 in the diagnostic is not really useful to the user. */
20306 error ("unable to deduce %qT from %qE", type, init);
20307 return error_mark_node;
20310 /* If the list of declarators contains more than one declarator, the type
20311 of each declared variable is determined as described above. If the
20312 type deduced for the template parameter U is not the same in each
20313 deduction, the program is ill-formed. */
20314 if (TREE_TYPE (auto_node)
20315 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20317 error ("inconsistent deduction for %qT: %qT and then %qT",
20318 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20319 return error_mark_node;
20321 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20323 if (processing_template_decl)
20324 targs = add_to_template_args (current_template_args (), targs);
20325 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20328 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20332 splice_late_return_type (tree type, tree late_return_type)
20336 if (late_return_type == NULL_TREE)
20338 argvec = make_tree_vec (1);
20339 TREE_VEC_ELT (argvec, 0) = late_return_type;
20340 if (processing_template_parmlist)
20341 /* For a late-specified return type in a template type-parameter, we
20342 need to add a dummy argument level for its parmlist. */
20343 argvec = add_to_template_args
20344 (make_tree_vec (processing_template_parmlist), argvec);
20345 if (current_template_parms)
20346 argvec = add_to_template_args (current_template_args (), argvec);
20347 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20350 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20353 is_auto (const_tree type)
20355 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20356 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20362 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20363 appear as a type-specifier for the declaration in question, we don't
20364 have to look through the whole type. */
20367 type_uses_auto (tree type)
20369 enum tree_code code;
20370 if (is_auto (type))
20373 code = TREE_CODE (type);
20375 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20376 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20377 || code == METHOD_TYPE || code == ARRAY_TYPE)
20378 return type_uses_auto (TREE_TYPE (type));
20380 if (TYPE_PTRMEMFUNC_P (type))
20381 return type_uses_auto (TREE_TYPE (TREE_TYPE
20382 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20387 /* For a given template T, return the vector of typedefs referenced
20388 in T for which access check is needed at T instantiation time.
20389 T is either a FUNCTION_DECL or a RECORD_TYPE.
20390 Those typedefs were added to T by the function
20391 append_type_to_template_for_access_check. */
20393 VEC(qualified_typedef_usage_t,gc)*
20394 get_types_needing_access_check (tree t)
20397 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20399 if (!t || t == error_mark_node)
20402 if (!(ti = get_template_info (t)))
20405 if (CLASS_TYPE_P (t)
20406 || TREE_CODE (t) == FUNCTION_DECL)
20408 if (!TI_TEMPLATE (ti))
20411 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20417 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20418 tied to T. That list of typedefs will be access checked at
20419 T instantiation time.
20420 T is either a FUNCTION_DECL or a RECORD_TYPE.
20421 TYPE_DECL is a TYPE_DECL node representing a typedef.
20422 SCOPE is the scope through which TYPE_DECL is accessed.
20423 LOCATION is the location of the usage point of TYPE_DECL.
20425 This function is a subroutine of
20426 append_type_to_template_for_access_check. */
20429 append_type_to_template_for_access_check_1 (tree t,
20432 location_t location)
20434 qualified_typedef_usage_t typedef_usage;
20437 if (!t || t == error_mark_node)
20440 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20441 || CLASS_TYPE_P (t))
20443 && TREE_CODE (type_decl) == TYPE_DECL
20446 if (!(ti = get_template_info (t)))
20449 gcc_assert (TI_TEMPLATE (ti));
20451 typedef_usage.typedef_decl = type_decl;
20452 typedef_usage.context = scope;
20453 typedef_usage.locus = location;
20455 VEC_safe_push (qualified_typedef_usage_t, gc,
20456 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20460 /* Append TYPE_DECL to the template TEMPL.
20461 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20462 At TEMPL instanciation time, TYPE_DECL will be checked to see
20463 if it can be accessed through SCOPE.
20464 LOCATION is the location of the usage point of TYPE_DECL.
20466 e.g. consider the following code snippet:
20473 template<class U> struct S
20475 C::myint mi; // <-- usage point of the typedef C::myint
20480 At S<char> instantiation time, we need to check the access of C::myint
20481 In other words, we need to check the access of the myint typedef through
20482 the C scope. For that purpose, this function will add the myint typedef
20483 and the scope C through which its being accessed to a list of typedefs
20484 tied to the template S. That list will be walked at template instantiation
20485 time and access check performed on each typedefs it contains.
20486 Note that this particular code snippet should yield an error because
20487 myint is private to C. */
20490 append_type_to_template_for_access_check (tree templ,
20493 location_t location)
20495 qualified_typedef_usage_t *iter;
20498 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20500 /* Make sure we don't append the type to the template twice. */
20501 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20502 get_types_needing_access_check (templ),
20504 if (iter->typedef_decl == type_decl && scope == iter->context)
20507 append_type_to_template_for_access_check_1 (templ, type_decl,
20511 /* Set up the hash tables for template instantiations. */
20514 init_template_processing (void)
20516 decl_specializations = htab_create_ggc (37,
20517 hash_specialization,
20518 eq_specializations,
20520 type_specializations = htab_create_ggc (37,
20521 hash_specialization,
20522 eq_specializations,
20526 /* Print stats about the template hash tables for -fstats. */
20529 print_template_statistics (void)
20531 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20532 "%f collisions\n", (long) htab_size (decl_specializations),
20533 (long) htab_elements (decl_specializations),
20534 htab_collisions (decl_specializations));
20535 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20536 "%f collisions\n", (long) htab_size (type_specializations),
20537 (long) htab_elements (type_specializations),
20538 htab_collisions (type_specializations));
20541 #include "gt-cp-pt.h"