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 /* Identify whether this is a parameter pack or not. */
2980 switch (TREE_CODE (t))
2982 case TEMPLATE_PARM_INDEX:
2983 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2984 parameter_pack_p = true;
2987 case TEMPLATE_TYPE_PARM:
2988 t = TYPE_MAIN_VARIANT (t);
2989 case TEMPLATE_TEMPLATE_PARM:
2990 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2991 parameter_pack_p = true;
2995 if (FUNCTION_PARAMETER_PACK_P (t))
2997 /* We don't want to walk into the type of a PARM_DECL,
2998 because we don't want to see the type parameter pack. */
3000 parameter_pack_p = true;
3005 parameter_pack_p = true;
3008 /* Not a parameter pack. */
3012 if (parameter_pack_p)
3014 /* Add this parameter pack to the list. */
3015 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3019 cp_walk_tree (&TYPE_CONTEXT (t),
3020 &find_parameter_packs_r, ppd, ppd->visited);
3022 /* This switch statement will return immediately if we don't find a
3024 switch (TREE_CODE (t))
3026 case TEMPLATE_PARM_INDEX:
3029 case BOUND_TEMPLATE_TEMPLATE_PARM:
3030 /* Check the template itself. */
3031 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3032 &find_parameter_packs_r, ppd, ppd->visited);
3033 /* Check the template arguments. */
3034 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3039 case TEMPLATE_TYPE_PARM:
3040 case TEMPLATE_TEMPLATE_PARM:
3047 if (TYPE_PTRMEMFUNC_P (t))
3053 if (TYPE_TEMPLATE_INFO (t))
3054 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3055 &find_parameter_packs_r, ppd, ppd->visited);
3062 cp_walk_tree (&TREE_TYPE (t),
3063 &find_parameter_packs_r, ppd, ppd->visited);
3067 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3072 case TYPE_PACK_EXPANSION:
3073 case EXPR_PACK_EXPANSION:
3078 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3083 case IDENTIFIER_NODE:
3084 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3096 /* Determines if the expression or type T uses any parameter packs. */
3098 uses_parameter_packs (tree t)
3100 tree parameter_packs = NULL_TREE;
3101 struct find_parameter_pack_data ppd;
3102 ppd.parameter_packs = ¶meter_packs;
3103 ppd.visited = pointer_set_create ();
3104 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3105 pointer_set_destroy (ppd.visited);
3106 return parameter_packs != NULL_TREE;
3109 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3110 representation a base-class initializer into a parameter pack
3111 expansion. If all goes well, the resulting node will be an
3112 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3115 make_pack_expansion (tree arg)
3118 tree parameter_packs = NULL_TREE;
3119 bool for_types = false;
3120 struct find_parameter_pack_data ppd;
3122 if (!arg || arg == error_mark_node)
3125 if (TREE_CODE (arg) == TREE_LIST)
3127 /* The only time we will see a TREE_LIST here is for a base
3128 class initializer. In this case, the TREE_PURPOSE will be a
3129 _TYPE node (representing the base class expansion we're
3130 initializing) and the TREE_VALUE will be a TREE_LIST
3131 containing the initialization arguments.
3133 The resulting expansion looks somewhat different from most
3134 expansions. Rather than returning just one _EXPANSION, we
3135 return a TREE_LIST whose TREE_PURPOSE is a
3136 TYPE_PACK_EXPANSION containing the bases that will be
3137 initialized. The TREE_VALUE will be identical to the
3138 original TREE_VALUE, which is a list of arguments that will
3139 be passed to each base. We do not introduce any new pack
3140 expansion nodes into the TREE_VALUE (although it is possible
3141 that some already exist), because the TREE_PURPOSE and
3142 TREE_VALUE all need to be expanded together with the same
3143 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3144 resulting TREE_PURPOSE will mention the parameter packs in
3145 both the bases and the arguments to the bases. */
3148 tree parameter_packs = NULL_TREE;
3150 /* Determine which parameter packs will be used by the base
3152 ppd.visited = pointer_set_create ();
3153 ppd.parameter_packs = ¶meter_packs;
3154 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3157 if (parameter_packs == NULL_TREE)
3159 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3160 pointer_set_destroy (ppd.visited);
3161 return error_mark_node;
3164 if (TREE_VALUE (arg) != void_type_node)
3166 /* Collect the sets of parameter packs used in each of the
3167 initialization arguments. */
3168 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3170 /* Determine which parameter packs will be expanded in this
3172 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3177 pointer_set_destroy (ppd.visited);
3179 /* Create the pack expansion type for the base type. */
3180 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3181 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3182 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3184 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3185 they will rarely be compared to anything. */
3186 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3188 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3191 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3194 /* Build the PACK_EXPANSION_* node. */
3196 ? cxx_make_type (TYPE_PACK_EXPANSION)
3197 : make_node (EXPR_PACK_EXPANSION);
3198 SET_PACK_EXPANSION_PATTERN (result, arg);
3199 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3201 /* Propagate type and const-expression information. */
3202 TREE_TYPE (result) = TREE_TYPE (arg);
3203 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3206 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3207 they will rarely be compared to anything. */
3208 SET_TYPE_STRUCTURAL_EQUALITY (result);
3210 /* Determine which parameter packs will be expanded. */
3211 ppd.parameter_packs = ¶meter_packs;
3212 ppd.visited = pointer_set_create ();
3213 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3214 pointer_set_destroy (ppd.visited);
3216 /* Make sure we found some parameter packs. */
3217 if (parameter_packs == NULL_TREE)
3220 error ("expansion pattern %<%T%> contains no argument packs", arg);
3222 error ("expansion pattern %<%E%> contains no argument packs", arg);
3223 return error_mark_node;
3225 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3230 /* Checks T for any "bare" parameter packs, which have not yet been
3231 expanded, and issues an error if any are found. This operation can
3232 only be done on full expressions or types (e.g., an expression
3233 statement, "if" condition, etc.), because we could have expressions like:
3235 foo(f(g(h(args)))...)
3237 where "args" is a parameter pack. check_for_bare_parameter_packs
3238 should not be called for the subexpressions args, h(args),
3239 g(h(args)), or f(g(h(args))), because we would produce erroneous
3242 Returns TRUE and emits an error if there were bare parameter packs,
3243 returns FALSE otherwise. */
3245 check_for_bare_parameter_packs (tree t)
3247 tree parameter_packs = NULL_TREE;
3248 struct find_parameter_pack_data ppd;
3250 if (!processing_template_decl || !t || t == error_mark_node)
3253 if (TREE_CODE (t) == TYPE_DECL)
3256 ppd.parameter_packs = ¶meter_packs;
3257 ppd.visited = pointer_set_create ();
3258 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3259 pointer_set_destroy (ppd.visited);
3261 if (parameter_packs)
3263 error ("parameter packs not expanded with %<...%>:");
3264 while (parameter_packs)
3266 tree pack = TREE_VALUE (parameter_packs);
3267 tree name = NULL_TREE;
3269 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3270 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3271 name = TYPE_NAME (pack);
3272 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3273 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3275 name = DECL_NAME (pack);
3278 inform (input_location, " %qD", name);
3280 inform (input_location, " <anonymous>");
3282 parameter_packs = TREE_CHAIN (parameter_packs);
3291 /* Expand any parameter packs that occur in the template arguments in
3294 expand_template_argument_pack (tree args)
3296 tree result_args = NULL_TREE;
3297 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3298 int num_result_args = -1;
3299 int non_default_args_count = -1;
3301 /* First, determine if we need to expand anything, and the number of
3302 slots we'll need. */
3303 for (in_arg = 0; in_arg < nargs; ++in_arg)
3305 tree arg = TREE_VEC_ELT (args, in_arg);
3306 if (arg == NULL_TREE)
3308 if (ARGUMENT_PACK_P (arg))
3310 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3311 if (num_result_args < 0)
3312 num_result_args = in_arg + num_packed;
3314 num_result_args += num_packed;
3318 if (num_result_args >= 0)
3323 /* If no expansion is necessary, we're done. */
3324 if (num_result_args < 0)
3327 /* Expand arguments. */
3328 result_args = make_tree_vec (num_result_args);
3329 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3330 non_default_args_count =
3331 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3332 for (in_arg = 0; in_arg < nargs; ++in_arg)
3334 tree arg = TREE_VEC_ELT (args, in_arg);
3335 if (ARGUMENT_PACK_P (arg))
3337 tree packed = ARGUMENT_PACK_ARGS (arg);
3338 int i, num_packed = TREE_VEC_LENGTH (packed);
3339 for (i = 0; i < num_packed; ++i, ++out_arg)
3340 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3341 if (non_default_args_count > 0)
3342 non_default_args_count += num_packed;
3346 TREE_VEC_ELT (result_args, out_arg) = arg;
3350 if (non_default_args_count >= 0)
3351 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3355 /* Checks if DECL shadows a template parameter.
3357 [temp.local]: A template-parameter shall not be redeclared within its
3358 scope (including nested scopes).
3360 Emits an error and returns TRUE if the DECL shadows a parameter,
3361 returns FALSE otherwise. */
3364 check_template_shadow (tree decl)
3368 /* If we're not in a template, we can't possibly shadow a template
3370 if (!current_template_parms)
3373 /* Figure out what we're shadowing. */
3374 if (TREE_CODE (decl) == OVERLOAD)
3375 decl = OVL_CURRENT (decl);
3376 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3378 /* If there's no previous binding for this name, we're not shadowing
3379 anything, let alone a template parameter. */
3383 /* If we're not shadowing a template parameter, we're done. Note
3384 that OLDDECL might be an OVERLOAD (or perhaps even an
3385 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3387 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3390 /* We check for decl != olddecl to avoid bogus errors for using a
3391 name inside a class. We check TPFI to avoid duplicate errors for
3392 inline member templates. */
3394 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3397 error ("declaration of %q+#D", decl);
3398 error (" shadows template parm %q+#D", olddecl);
3402 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3403 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3404 template parameters. */
3407 build_template_parm_index (int index,
3414 tree t = make_node (TEMPLATE_PARM_INDEX);
3415 TEMPLATE_PARM_IDX (t) = index;
3416 TEMPLATE_PARM_LEVEL (t) = level;
3417 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3418 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3419 TEMPLATE_PARM_DECL (t) = decl;
3420 TREE_TYPE (t) = type;
3421 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3422 TREE_READONLY (t) = TREE_READONLY (decl);
3427 /* Find the canonical type parameter for the given template type
3428 parameter. Returns the canonical type parameter, which may be TYPE
3429 if no such parameter existed. */
3432 canonical_type_parameter (tree type)
3435 int idx = TEMPLATE_TYPE_IDX (type);
3436 if (!canonical_template_parms)
3437 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3439 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3440 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3442 list = VEC_index (tree, canonical_template_parms, idx);
3443 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3444 list = TREE_CHAIN (list);
3447 return TREE_VALUE (list);
3450 VEC_replace(tree, canonical_template_parms, idx,
3451 tree_cons (NULL_TREE, type,
3452 VEC_index (tree, canonical_template_parms, idx)));
3457 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3458 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3459 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3460 new one is created. */
3463 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3464 tsubst_flags_t complain)
3466 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3467 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3468 != TEMPLATE_PARM_LEVEL (index) - levels)
3469 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3471 tree orig_decl = TEMPLATE_PARM_DECL (index);
3474 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3475 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3476 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3477 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3478 DECL_ARTIFICIAL (decl) = 1;
3479 SET_DECL_TEMPLATE_PARM_P (decl);
3481 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3482 TEMPLATE_PARM_LEVEL (index) - levels,
3483 TEMPLATE_PARM_ORIG_LEVEL (index),
3484 TEMPLATE_PARM_NUM_SIBLINGS (index),
3486 TEMPLATE_PARM_DESCENDANTS (index) = t;
3487 TEMPLATE_PARM_PARAMETER_PACK (t)
3488 = TEMPLATE_PARM_PARAMETER_PACK (index);
3490 /* Template template parameters need this. */
3491 if (TREE_CODE (decl) == TEMPLATE_DECL)
3492 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3493 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3497 return TEMPLATE_PARM_DESCENDANTS (index);
3500 /* Process information from new template parameter PARM and append it
3501 to the LIST being built. This new parameter is a non-type
3502 parameter iff IS_NON_TYPE is true. This new parameter is a
3503 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3504 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3505 parameter list PARM belongs to. This is used used to create a
3506 proper canonical type for the type of PARM that is to be created,
3507 iff PARM is a type. If the size is not known, this parameter shall
3511 process_template_parm (tree list, location_t parm_loc, tree parm,
3512 bool is_non_type, bool is_parameter_pack,
3513 unsigned num_template_parms)
3520 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3521 defval = TREE_PURPOSE (parm);
3525 tree p = tree_last (list);
3527 if (p && TREE_VALUE (p) != error_mark_node)
3530 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3531 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3533 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3543 parm = TREE_VALUE (parm);
3545 SET_DECL_TEMPLATE_PARM_P (parm);
3547 if (TREE_TYPE (parm) == error_mark_node)
3549 err_parm_list = build_tree_list (defval, parm);
3550 TREE_VALUE (err_parm_list) = error_mark_node;
3551 return chainon (list, err_parm_list);
3557 The top-level cv-qualifiers on the template-parameter are
3558 ignored when determining its type. */
3559 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3560 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3562 err_parm_list = build_tree_list (defval, parm);
3563 TREE_VALUE (err_parm_list) = error_mark_node;
3564 return chainon (list, err_parm_list);
3567 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3569 /* This template parameter is not a parameter pack, but it
3570 should be. Complain about "bare" parameter packs. */
3571 check_for_bare_parameter_packs (TREE_TYPE (parm));
3573 /* Recover by calling this a parameter pack. */
3574 is_parameter_pack = true;
3578 /* A template parameter is not modifiable. */
3579 TREE_CONSTANT (parm) = 1;
3580 TREE_READONLY (parm) = 1;
3581 decl = build_decl (parm_loc,
3582 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3583 TREE_CONSTANT (decl) = 1;
3584 TREE_READONLY (decl) = 1;
3585 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3586 = build_template_parm_index (idx, processing_template_decl,
3587 processing_template_decl,
3589 decl, TREE_TYPE (parm));
3591 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3592 = is_parameter_pack;
3597 parm = TREE_VALUE (TREE_VALUE (parm));
3599 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3601 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3602 /* This is for distinguishing between real templates and template
3603 template parameters */
3604 TREE_TYPE (parm) = t;
3605 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3610 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3611 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3612 decl = build_decl (parm_loc,
3613 TYPE_DECL, parm, t);
3616 TYPE_NAME (t) = decl;
3617 TYPE_STUB_DECL (t) = decl;
3619 TEMPLATE_TYPE_PARM_INDEX (t)
3620 = build_template_parm_index (idx, processing_template_decl,
3621 processing_template_decl,
3623 decl, TREE_TYPE (parm));
3624 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3625 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3627 DECL_ARTIFICIAL (decl) = 1;
3628 SET_DECL_TEMPLATE_PARM_P (decl);
3630 parm = build_tree_list (defval, parm);
3631 return chainon (list, parm);
3634 /* The end of a template parameter list has been reached. Process the
3635 tree list into a parameter vector, converting each parameter into a more
3636 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3640 end_template_parm_list (tree parms)
3644 tree saved_parmlist = make_tree_vec (list_length (parms));
3646 current_template_parms
3647 = tree_cons (size_int (processing_template_decl),
3648 saved_parmlist, current_template_parms);
3650 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3652 next = TREE_CHAIN (parm);
3653 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3654 TREE_CHAIN (parm) = NULL_TREE;
3657 --processing_template_parmlist;
3659 return saved_parmlist;
3662 /* Create a new type almost identical to TYPE but which has the
3663 following differences:
3665 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3666 template sibling parameters of T.
3668 2/ T has a new canonical type that matches the new number
3671 3/ From now on, T is going to be what lookups referring to the
3672 name of TYPE will return. No lookup should return TYPE anymore.
3674 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3676 This is a subroutine of fixup_template_parms. */
3679 fixup_template_type_parm_type (tree type, int num_parms)
3681 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3683 /* This is the decl which name is inserted into the symbol table for
3684 the template parm type. So whenever we lookup the type name, this
3685 is the DECL we get. */
3688 /* Do not fix up the type twice. */
3689 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3692 t = copy_type (type);
3693 decl = TYPE_NAME (t);
3695 TYPE_MAIN_VARIANT (t) = t;
3696 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3697 TYPE_POINTER_TO (t) = 0;
3698 TYPE_REFERENCE_TO (t) = 0;
3700 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3701 TEMPLATE_PARM_LEVEL (orig_idx),
3702 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3705 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3706 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3707 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3709 TYPE_STUB_DECL (t) = decl;
3710 TEMPLATE_TYPE_DECL (t) = decl;
3711 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3712 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3714 /* Update the type associated to the type name stored in the symbol
3715 table. Now, whenever the type name is looked up, the resulting
3716 type is properly fixed up. */
3717 TREE_TYPE (decl) = t;
3719 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3724 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3725 identical to I, but that is fixed up as to:
3727 1/ carry the number of sibling parms (NUM_PARMS) of the template
3728 parm represented by I.
3730 2/ replace all references to template parm types declared before I
3731 (in the same template parm list as I) by references to template
3732 parm types contained in ARGS. ARGS should contain the list of
3733 template parms that have been fixed up so far, in a form suitable
3734 to be passed to tsubst.
3736 This is a subroutine of fixup_template_parms. */
3739 fixup_template_parm_index (tree i, tree args, int num_parms)
3741 tree index, decl, type;
3744 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3745 /* Do not fix up the index twice. */
3746 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3749 decl = TEMPLATE_PARM_DECL (i);
3750 type = TREE_TYPE (decl);
3752 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3753 TEMPLATE_PARM_LEVEL (i),
3754 TEMPLATE_PARM_ORIG_LEVEL (i),
3758 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3759 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3761 type = tsubst (type, args, tf_none, NULL_TREE);
3763 TREE_TYPE (decl) = type;
3764 TREE_TYPE (index) = type;
3770 This is a subroutine of fixup_template_parms.
3772 It computes the canonical type of the type of the template
3773 parameter PARM_DESC and update all references to that type so that
3774 they use the newly computed canonical type. No access check is
3775 performed during the fixup. PARM_DESC is a TREE_LIST which
3776 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3777 default argument of the template parm if any. IDX is the index of
3778 the template parameter, starting at 0. NUM_PARMS is the number of
3779 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3780 TREE_VEC containing the full set of template parameters in a form
3781 suitable to be passed to substs functions as their ARGS
3782 argument. This is what current_template_args returns for a given
3783 template. The innermost vector of args in ARGLIST is the set of
3784 template parms that have been fixed up so far. This function adds
3785 the fixed up parameter into that vector. */
3788 fixup_template_parm (tree parm_desc,
3793 tree parm = TREE_VALUE (parm_desc);
3794 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3796 push_deferring_access_checks (dk_no_check);
3798 if (TREE_CODE (parm) == TYPE_DECL)
3800 /* PARM is a template type parameter. Fix up its type, add
3801 the fixed-up template parm to the vector of fixed-up
3802 template parms so far, and substitute the fixed-up
3803 template parms into the default argument of this
3806 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3807 TREE_TYPE (parm) = t;
3809 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3811 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3813 /* PARM is a template template parameter. This is going to
3815 tree tparms, targs, innermost_args, t;
3818 /* First, fix up the parms of the template template parm
3819 because the parms are involved in defining the new canonical
3820 type of the template template parm. */
3822 /* So we need to substitute the template parm types that have
3823 been fixed up so far into the template parms of this template
3824 template parm. E.g, consider this:
3826 template<class T, template<T u> class TT> class S;
3828 In this case we want to substitute T into the
3829 template parameters of TT.
3831 So let's walk the template parms of PARM here, and
3832 tsubst ARGLIST into into each of the template
3835 /* For this substitution we need to build the full set of
3836 template parameters and use that as arguments for the
3837 tsubsting function. */
3838 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3840 /* This will contain the innermost parms of PARM into which
3841 we have substituted so far. */
3842 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3843 targs = add_to_template_args (arglist, innermost_args);
3844 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3848 parameter = TREE_VEC_ELT (tparms, j);
3850 /* INNERMOST_ARGS needs to have at least the same number
3851 of elements as the index PARAMETER, ortherwise
3852 tsubsting into PARAMETER will result in partially
3853 instantiating it, reducing its tempate parm
3854 level. Let's tactically fill INNERMOST_ARGS for that
3856 TREE_VEC_ELT (innermost_args, j) =
3857 template_parm_to_arg (parameter);
3859 fixup_template_parm (parameter, j,
3860 TREE_VEC_LENGTH (tparms),
3864 /* Now fix up the type of the template template parm. */
3866 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3867 TREE_TYPE (parm) = t;
3869 TREE_VEC_ELT (fixedup_args, idx) =
3870 template_parm_to_arg (parm_desc);
3872 else if (TREE_CODE (parm) == PARM_DECL)
3874 /* PARM is a non-type template parameter. We need to:
3876 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3877 proper number of sibling parameters.
3879 * Make lookups of the template parameter return a reference
3880 to the fixed-up index. No lookup should return references
3881 to the former index anymore.
3883 * Substitute the template parms that got fixed up so far
3885 * into the type of PARM. */
3887 tree index = DECL_INITIAL (parm);
3889 /* PUSHED_DECL is the decl added to the symbol table with
3890 the name of the parameter. E,g:
3892 template<class T, T u> //#0
3893 auto my_function(T t) -> decltype(u); //#1
3895 Here, when looking up u at //#1, we get the decl of u
3896 resulting from the declaration in #0. This is what
3897 PUSHED_DECL is. We need to replace the reference to the
3898 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3899 fixed-up TEMPLATE_PARM_INDEX. */
3900 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3902 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3903 fixup the type of PUSHED_DECL as well and luckily
3904 fixup_template_parm_index does it for us too. */
3905 tree fixed_up_index =
3906 fixup_template_parm_index (index, arglist, num_parms);
3908 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3910 /* Add this fixed up PARM to the template parms we've fixed
3911 up so far and use that to substitute the fixed-up
3912 template parms into the type of PARM. */
3913 TREE_VEC_ELT (fixedup_args, idx) =
3914 template_parm_to_arg (parm_desc);
3915 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3916 tf_none, NULL_TREE);
3919 TREE_PURPOSE (parm_desc) =
3920 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3921 arglist, tf_none, parm);
3923 pop_deferring_access_checks ();
3926 /* Walk the current template parms and properly compute the canonical
3927 types of the dependent types created during
3928 cp_parser_template_parameter_list. */
3931 fixup_template_parms (void)
3938 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3939 if (parameter_vec == NULL_TREE)
3942 num_parms = TREE_VEC_LENGTH (parameter_vec);
3944 /* This vector contains the current innermost template parms that
3945 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3946 to be passed to tsubst* functions as their ARGS argument. */
3947 fixedup_args = make_tree_vec (num_parms);
3949 /* This vector contains the full set of template parms in a form
3950 suitable to be passed to substs functions as their ARGS
3952 arglist = current_template_args ();
3953 arglist = add_outermost_template_args (arglist, fixedup_args);
3955 /* Let's do the proper fixup now. */
3956 for (i = 0; i < num_parms; ++i)
3957 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3958 i, num_parms, arglist);
3961 /* end_template_decl is called after a template declaration is seen. */
3964 end_template_decl (void)
3966 reset_specialization ();
3968 if (! processing_template_decl)
3971 /* This matches the pushlevel in begin_template_parm_list. */
3974 --processing_template_decl;
3975 current_template_parms = TREE_CHAIN (current_template_parms);
3978 /* Takes a TREE_LIST representing a template parameter and convert it
3979 into an argument suitable to be passed to the type substitution
3980 functions. Note that If the TREE_LIST contains an error_mark
3981 node, the returned argument is error_mark_node. */
3984 template_parm_to_arg (tree t)
3988 || TREE_CODE (t) != TREE_LIST)
3991 if (error_operand_p (TREE_VALUE (t)))
3992 return error_mark_node;
3996 if (TREE_CODE (t) == TYPE_DECL
3997 || TREE_CODE (t) == TEMPLATE_DECL)
4001 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4003 /* Turn this argument into a TYPE_ARGUMENT_PACK
4004 with a single element, which expands T. */
4005 tree vec = make_tree_vec (1);
4006 #ifdef ENABLE_CHECKING
4007 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4008 (vec, TREE_VEC_LENGTH (vec));
4010 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4012 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4013 SET_ARGUMENT_PACK_ARGS (t, vec);
4018 t = DECL_INITIAL (t);
4020 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4022 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4023 with a single element, which expands T. */
4024 tree vec = make_tree_vec (1);
4025 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4026 #ifdef ENABLE_CHECKING
4027 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4028 (vec, TREE_VEC_LENGTH (vec));
4030 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4032 t = make_node (NONTYPE_ARGUMENT_PACK);
4033 SET_ARGUMENT_PACK_ARGS (t, vec);
4034 TREE_TYPE (t) = type;
4040 /* This function returns TRUE if PARM_PACK is a template parameter
4041 pack and if ARG_PACK is what template_parm_to_arg returned when
4042 passed PARM_PACK. */
4045 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4047 /* For clarity in the comments below let's use the representation
4048 argument_pack<elements>' to denote an argument pack and its
4051 In the 'if' block below, we want to detect cases where
4052 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4053 check if ARG_PACK is an argument pack which sole element is
4054 the expansion of PARM_PACK. That argument pack is typically
4055 created by template_parm_to_arg when passed a parameter
4059 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4060 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4062 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4063 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4064 /* So we have an argument_pack<P...>. We want to test if P
4065 is actually PARM_PACK. We will not use cp_tree_equal to
4066 test P and PARM_PACK because during type fixup (by
4067 fixup_template_parm) P can be a pre-fixup version of a
4068 type and PARM_PACK be its post-fixup version.
4069 cp_tree_equal would consider them as different even
4070 though we would want to consider them compatible for our
4071 precise purpose here.
4073 Thus we are going to consider that P and PARM_PACK are
4074 compatible if they have the same DECL. */
4075 if ((/* If ARG_PACK is a type parameter pack named by the
4076 same DECL as parm_pack ... */
4078 && TYPE_P (parm_pack)
4079 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4080 /* ... or if PARM_PACK is a non-type parameter named by the
4081 same DECL as ARG_PACK. Note that PARM_PACK being a
4082 non-type parameter means it's either a PARM_DECL or a
4083 TEMPLATE_PARM_INDEX. */
4084 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4085 && ((TREE_CODE (parm_pack) == PARM_DECL
4086 && (TEMPLATE_PARM_DECL (pattern)
4087 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4088 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4089 && (TEMPLATE_PARM_DECL (pattern)
4090 == TEMPLATE_PARM_DECL (parm_pack))))))
4091 && template_parameter_pack_p (pattern))
4097 /* Within the declaration of a template, return all levels of template
4098 parameters that apply. The template parameters are represented as
4099 a TREE_VEC, in the form documented in cp-tree.h for template
4103 current_template_args (void)
4106 tree args = NULL_TREE;
4107 int length = TMPL_PARMS_DEPTH (current_template_parms);
4110 /* If there is only one level of template parameters, we do not
4111 create a TREE_VEC of TREE_VECs. Instead, we return a single
4112 TREE_VEC containing the arguments. */
4114 args = make_tree_vec (length);
4116 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4118 tree a = copy_node (TREE_VALUE (header));
4121 TREE_TYPE (a) = NULL_TREE;
4122 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4123 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4125 #ifdef ENABLE_CHECKING
4126 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4130 TREE_VEC_ELT (args, --l) = a;
4135 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4136 /* This can happen for template parms of a template template
4139 template<template<class T, class U> class TT> struct S;
4141 Consider the level of the parms of TT; T and U both have
4142 level 2; TT has no template parm of level 1. So in this case
4143 the first element of full_template_args is NULL_TREE. If we
4144 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4145 of 2. This will make tsubst wrongly consider that T and U
4146 have level 1. Instead, let's create a dummy vector as the
4147 first element of full_template_args so that TMPL_ARG_DEPTH
4148 returns the correct depth for args. */
4149 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4153 /* Update the declared TYPE by doing any lookups which were thought to be
4154 dependent, but are not now that we know the SCOPE of the declarator. */
4157 maybe_update_decl_type (tree orig_type, tree scope)
4159 tree type = orig_type;
4161 if (type == NULL_TREE)
4164 if (TREE_CODE (orig_type) == TYPE_DECL)
4165 type = TREE_TYPE (type);
4167 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4168 && dependent_type_p (type)
4169 /* Don't bother building up the args in this case. */
4170 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4172 /* tsubst in the args corresponding to the template parameters,
4173 including auto if present. Most things will be unchanged, but
4174 make_typename_type and tsubst_qualified_id will resolve
4175 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4176 tree args = current_template_args ();
4177 tree auto_node = type_uses_auto (type);
4181 tree auto_vec = make_tree_vec (1);
4182 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4183 args = add_to_template_args (args, auto_vec);
4185 pushed = push_scope (scope);
4186 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4191 if (type == error_mark_node)
4194 if (TREE_CODE (orig_type) == TYPE_DECL)
4196 if (same_type_p (type, TREE_TYPE (orig_type)))
4199 type = TYPE_NAME (type);
4204 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4205 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4206 a member template. Used by push_template_decl below. */
4209 build_template_decl (tree decl, tree parms, bool member_template_p)
4211 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4212 DECL_TEMPLATE_PARMS (tmpl) = parms;
4213 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4214 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4215 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4220 struct template_parm_data
4222 /* The level of the template parameters we are currently
4226 /* The index of the specialization argument we are currently
4230 /* An array whose size is the number of template parameters. The
4231 elements are nonzero if the parameter has been used in any one
4232 of the arguments processed so far. */
4235 /* An array whose size is the number of template arguments. The
4236 elements are nonzero if the argument makes use of template
4237 parameters of this level. */
4238 int* arg_uses_template_parms;
4241 /* Subroutine of push_template_decl used to see if each template
4242 parameter in a partial specialization is used in the explicit
4243 argument list. If T is of the LEVEL given in DATA (which is
4244 treated as a template_parm_data*), then DATA->PARMS is marked
4248 mark_template_parm (tree t, void* data)
4252 struct template_parm_data* tpd = (struct template_parm_data*) data;
4254 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4256 level = TEMPLATE_PARM_LEVEL (t);
4257 idx = TEMPLATE_PARM_IDX (t);
4261 level = TEMPLATE_TYPE_LEVEL (t);
4262 idx = TEMPLATE_TYPE_IDX (t);
4265 if (level == tpd->level)
4267 tpd->parms[idx] = 1;
4268 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4271 /* Return zero so that for_each_template_parm will continue the
4272 traversal of the tree; we want to mark *every* template parm. */
4276 /* Process the partial specialization DECL. */
4279 process_partial_specialization (tree decl)
4281 tree type = TREE_TYPE (decl);
4282 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4283 tree specargs = CLASSTYPE_TI_ARGS (type);
4284 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4285 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4288 int nargs = TREE_VEC_LENGTH (inner_args);
4291 bool did_error_intro = false;
4292 struct template_parm_data tpd;
4293 struct template_parm_data tpd2;
4295 gcc_assert (current_template_parms);
4297 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4298 ntparms = TREE_VEC_LENGTH (inner_parms);
4300 /* We check that each of the template parameters given in the
4301 partial specialization is used in the argument list to the
4302 specialization. For example:
4304 template <class T> struct S;
4305 template <class T> struct S<T*>;
4307 The second declaration is OK because `T*' uses the template
4308 parameter T, whereas
4310 template <class T> struct S<int>;
4312 is no good. Even trickier is:
4323 The S2<T> declaration is actually invalid; it is a
4324 full-specialization. Of course,
4327 struct S2<T (*)(U)>;
4329 or some such would have been OK. */
4330 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4331 tpd.parms = XALLOCAVEC (int, ntparms);
4332 memset (tpd.parms, 0, sizeof (int) * ntparms);
4334 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4335 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4336 for (i = 0; i < nargs; ++i)
4338 tpd.current_arg = i;
4339 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4340 &mark_template_parm,
4343 /*include_nondeduced_p=*/false);
4345 for (i = 0; i < ntparms; ++i)
4346 if (tpd.parms[i] == 0)
4348 /* One of the template parms was not used in the
4350 if (!did_error_intro)
4352 error ("template parameters not used in partial specialization:");
4353 did_error_intro = true;
4356 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4359 if (did_error_intro)
4360 return error_mark_node;
4362 /* [temp.class.spec]
4364 The argument list of the specialization shall not be identical to
4365 the implicit argument list of the primary template. */
4366 if (comp_template_args
4368 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4370 error ("partial specialization %qT does not specialize any template arguments", type);
4372 /* [temp.class.spec]
4374 A partially specialized non-type argument expression shall not
4375 involve template parameters of the partial specialization except
4376 when the argument expression is a simple identifier.
4378 The type of a template parameter corresponding to a specialized
4379 non-type argument shall not be dependent on a parameter of the
4382 Also, we verify that pack expansions only occur at the
4383 end of the argument list. */
4384 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4386 for (i = 0; i < nargs; ++i)
4388 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4389 tree arg = TREE_VEC_ELT (inner_args, i);
4390 tree packed_args = NULL_TREE;
4393 if (ARGUMENT_PACK_P (arg))
4395 /* Extract the arguments from the argument pack. We'll be
4396 iterating over these in the following loop. */
4397 packed_args = ARGUMENT_PACK_ARGS (arg);
4398 len = TREE_VEC_LENGTH (packed_args);
4401 for (j = 0; j < len; j++)
4404 /* Get the Jth argument in the parameter pack. */
4405 arg = TREE_VEC_ELT (packed_args, j);
4407 if (PACK_EXPANSION_P (arg))
4409 /* Pack expansions must come at the end of the
4411 if ((packed_args && j < len - 1)
4412 || (!packed_args && i < nargs - 1))
4414 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4415 error ("parameter pack argument %qE must be at the "
4416 "end of the template argument list", arg);
4418 error ("parameter pack argument %qT must be at the "
4419 "end of the template argument list", arg);
4423 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4424 /* We only care about the pattern. */
4425 arg = PACK_EXPANSION_PATTERN (arg);
4427 if (/* These first two lines are the `non-type' bit. */
4429 && TREE_CODE (arg) != TEMPLATE_DECL
4430 /* This next line is the `argument expression is not just a
4431 simple identifier' condition and also the `specialized
4432 non-type argument' bit. */
4433 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4435 if ((!packed_args && tpd.arg_uses_template_parms[i])
4436 || (packed_args && uses_template_parms (arg)))
4437 error ("template argument %qE involves template parameter(s)",
4441 /* Look at the corresponding template parameter,
4442 marking which template parameters its type depends
4444 tree type = TREE_TYPE (parm);
4448 /* We haven't yet initialized TPD2. Do so now. */
4449 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4450 /* The number of parameters here is the number in the
4451 main template, which, as checked in the assertion
4453 tpd2.parms = XALLOCAVEC (int, nargs);
4455 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4458 /* Mark the template parameters. But this time, we're
4459 looking for the template parameters of the main
4460 template, not in the specialization. */
4461 tpd2.current_arg = i;
4462 tpd2.arg_uses_template_parms[i] = 0;
4463 memset (tpd2.parms, 0, sizeof (int) * nargs);
4464 for_each_template_parm (type,
4465 &mark_template_parm,
4468 /*include_nondeduced_p=*/false);
4470 if (tpd2.arg_uses_template_parms [i])
4472 /* The type depended on some template parameters.
4473 If they are fully specialized in the
4474 specialization, that's OK. */
4477 for (j = 0; j < nargs; ++j)
4478 if (tpd2.parms[j] != 0
4479 && tpd.arg_uses_template_parms [j])
4482 error_n (input_location, count,
4483 "type %qT of template argument %qE depends "
4484 "on a template parameter",
4485 "type %qT of template argument %qE depends "
4486 "on template parameters",
4495 /* We should only get here once. */
4496 gcc_assert (!COMPLETE_TYPE_P (type));
4498 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4499 = tree_cons (specargs, inner_parms,
4500 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4501 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4503 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4504 inst = TREE_CHAIN (inst))
4506 tree inst_type = TREE_VALUE (inst);
4507 if (COMPLETE_TYPE_P (inst_type)
4508 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4510 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4511 if (spec && TREE_TYPE (spec) == type)
4512 permerror (input_location,
4513 "partial specialization of %qT after instantiation "
4514 "of %qT", type, inst_type);
4521 /* Check that a template declaration's use of default arguments and
4522 parameter packs is not invalid. Here, PARMS are the template
4523 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4524 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4528 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4529 declaration (but not a definition); 1 indicates a declaration, 2
4530 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4531 emitted for extraneous default arguments.
4533 Returns TRUE if there were no errors found, FALSE otherwise. */
4536 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4537 int is_partial, int is_friend_decl)
4540 int last_level_to_check;
4542 bool no_errors = true;
4546 A default template-argument shall not be specified in a
4547 function template declaration or a function template definition, nor
4548 in the template-parameter-list of the definition of a member of a
4551 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4552 /* You can't have a function template declaration in a local
4553 scope, nor you can you define a member of a class template in a
4557 if (current_class_type
4558 && !TYPE_BEING_DEFINED (current_class_type)
4559 && DECL_LANG_SPECIFIC (decl)
4560 && DECL_DECLARES_FUNCTION_P (decl)
4561 /* If this is either a friend defined in the scope of the class
4562 or a member function. */
4563 && (DECL_FUNCTION_MEMBER_P (decl)
4564 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4565 : DECL_FRIEND_CONTEXT (decl)
4566 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4568 /* And, if it was a member function, it really was defined in
4569 the scope of the class. */
4570 && (!DECL_FUNCTION_MEMBER_P (decl)
4571 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4572 /* We already checked these parameters when the template was
4573 declared, so there's no need to do it again now. This function
4574 was defined in class scope, but we're processing it's body now
4575 that the class is complete. */
4578 /* Core issue 226 (C++0x only): the following only applies to class
4580 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4584 If a template-parameter has a default template-argument, all
4585 subsequent template-parameters shall have a default
4586 template-argument supplied. */
4587 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4589 tree inner_parms = TREE_VALUE (parm_level);
4590 int ntparms = TREE_VEC_LENGTH (inner_parms);
4591 int seen_def_arg_p = 0;
4594 for (i = 0; i < ntparms; ++i)
4596 tree parm = TREE_VEC_ELT (inner_parms, i);
4598 if (parm == error_mark_node)
4601 if (TREE_PURPOSE (parm))
4603 else if (seen_def_arg_p
4604 && !template_parameter_pack_p (TREE_VALUE (parm)))
4606 error ("no default argument for %qD", TREE_VALUE (parm));
4607 /* For better subsequent error-recovery, we indicate that
4608 there should have been a default argument. */
4609 TREE_PURPOSE (parm) = error_mark_node;
4615 /* Don't complain about an enclosing partial
4617 && parm_level == parms
4618 && TREE_CODE (decl) == TYPE_DECL
4620 && template_parameter_pack_p (TREE_VALUE (parm)))
4622 /* A primary class template can only have one
4623 parameter pack, at the end of the template
4626 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4627 error ("parameter pack %qE must be at the end of the"
4628 " template parameter list", TREE_VALUE (parm));
4630 error ("parameter pack %qT must be at the end of the"
4631 " template parameter list",
4632 TREE_TYPE (TREE_VALUE (parm)));
4634 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4642 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4646 /* For an ordinary class template, default template arguments are
4647 allowed at the innermost level, e.g.:
4648 template <class T = int>
4650 but, in a partial specialization, they're not allowed even
4651 there, as we have in [temp.class.spec]:
4653 The template parameter list of a specialization shall not
4654 contain default template argument values.
4656 So, for a partial specialization, or for a function template
4657 (in C++98/C++03), we look at all of them. */
4660 /* But, for a primary class template that is not a partial
4661 specialization we look at all template parameters except the
4663 parms = TREE_CHAIN (parms);
4665 /* Figure out what error message to issue. */
4666 if (is_friend_decl == 2)
4667 msg = G_("default template arguments may not be used in function template "
4668 "friend re-declaration");
4669 else if (is_friend_decl)
4670 msg = G_("default template arguments may not be used in function template "
4671 "friend declarations");
4672 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4673 msg = G_("default template arguments may not be used in function templates "
4674 "without -std=c++11 or -std=gnu++11");
4675 else if (is_partial)
4676 msg = G_("default template arguments may not be used in "
4677 "partial specializations");
4679 msg = G_("default argument for template parameter for class enclosing %qD");
4681 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4682 /* If we're inside a class definition, there's no need to
4683 examine the parameters to the class itself. On the one
4684 hand, they will be checked when the class is defined, and,
4685 on the other, default arguments are valid in things like:
4686 template <class T = double>
4687 struct S { template <class U> void f(U); };
4688 Here the default argument for `S' has no bearing on the
4689 declaration of `f'. */
4690 last_level_to_check = template_class_depth (current_class_type) + 1;
4692 /* Check everything. */
4693 last_level_to_check = 0;
4695 for (parm_level = parms;
4696 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4697 parm_level = TREE_CHAIN (parm_level))
4699 tree inner_parms = TREE_VALUE (parm_level);
4703 ntparms = TREE_VEC_LENGTH (inner_parms);
4704 for (i = 0; i < ntparms; ++i)
4706 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4709 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4714 if (is_friend_decl == 2)
4721 /* Clear out the default argument so that we are not
4723 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4727 /* At this point, if we're still interested in issuing messages,
4728 they must apply to classes surrounding the object declared. */
4730 msg = G_("default argument for template parameter for class "
4737 /* Worker for push_template_decl_real, called via
4738 for_each_template_parm. DATA is really an int, indicating the
4739 level of the parameters we are interested in. If T is a template
4740 parameter of that level, return nonzero. */
4743 template_parm_this_level_p (tree t, void* data)
4745 int this_level = *(int *)data;
4748 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4749 level = TEMPLATE_PARM_LEVEL (t);
4751 level = TEMPLATE_TYPE_LEVEL (t);
4752 return level == this_level;
4755 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4756 parameters given by current_template_args, or reuses a
4757 previously existing one, if appropriate. Returns the DECL, or an
4758 equivalent one, if it is replaced via a call to duplicate_decls.
4760 If IS_FRIEND is true, DECL is a friend declaration. */
4763 push_template_decl_real (tree decl, bool is_friend)
4771 int new_template_p = 0;
4772 /* True if the template is a member template, in the sense of
4774 bool member_template_p = false;
4776 if (decl == error_mark_node || !current_template_parms)
4777 return error_mark_node;
4779 /* See if this is a partial specialization. */
4780 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4781 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4782 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4784 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4788 /* For a friend, we want the context of the friend function, not
4789 the type of which it is a friend. */
4790 ctx = CP_DECL_CONTEXT (decl);
4791 else if (CP_DECL_CONTEXT (decl)
4792 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4793 /* In the case of a virtual function, we want the class in which
4795 ctx = CP_DECL_CONTEXT (decl);
4797 /* Otherwise, if we're currently defining some class, the DECL
4798 is assumed to be a member of the class. */
4799 ctx = current_scope ();
4801 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4804 if (!DECL_CONTEXT (decl))
4805 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4807 /* See if this is a primary template. */
4808 if (is_friend && ctx)
4809 /* A friend template that specifies a class context, i.e.
4810 template <typename T> friend void A<T>::f();
4814 primary = template_parm_scope_p ();
4818 if (DECL_CLASS_SCOPE_P (decl))
4819 member_template_p = true;
4820 if (TREE_CODE (decl) == TYPE_DECL
4821 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4823 error ("template class without a name");
4824 return error_mark_node;
4826 else if (TREE_CODE (decl) == FUNCTION_DECL)
4828 if (DECL_DESTRUCTOR_P (decl))
4832 A destructor shall not be a member template. */
4833 error ("destructor %qD declared as member template", decl);
4834 return error_mark_node;
4836 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4837 && (!prototype_p (TREE_TYPE (decl))
4838 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4839 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4840 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4841 == void_list_node)))
4843 /* [basic.stc.dynamic.allocation]
4845 An allocation function can be a function
4846 template. ... Template allocation functions shall
4847 have two or more parameters. */
4848 error ("invalid template declaration of %qD", decl);
4849 return error_mark_node;
4852 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4853 && CLASS_TYPE_P (TREE_TYPE (decl)))
4855 else if (TREE_CODE (decl) == TYPE_DECL
4856 && TYPE_DECL_ALIAS_P (decl))
4857 /* alias-declaration */
4858 gcc_assert (!DECL_ARTIFICIAL (decl));
4861 error ("template declaration of %q#D", decl);
4862 return error_mark_node;
4866 /* Check to see that the rules regarding the use of default
4867 arguments are not being violated. */
4868 check_default_tmpl_args (decl, current_template_parms,
4869 primary, is_partial, /*is_friend_decl=*/0);
4871 /* Ensure that there are no parameter packs in the type of this
4872 declaration that have not been expanded. */
4873 if (TREE_CODE (decl) == FUNCTION_DECL)
4875 /* Check each of the arguments individually to see if there are
4876 any bare parameter packs. */
4877 tree type = TREE_TYPE (decl);
4878 tree arg = DECL_ARGUMENTS (decl);
4879 tree argtype = TYPE_ARG_TYPES (type);
4881 while (arg && argtype)
4883 if (!FUNCTION_PARAMETER_PACK_P (arg)
4884 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4886 /* This is a PARM_DECL that contains unexpanded parameter
4887 packs. We have already complained about this in the
4888 check_for_bare_parameter_packs call, so just replace
4889 these types with ERROR_MARK_NODE. */
4890 TREE_TYPE (arg) = error_mark_node;
4891 TREE_VALUE (argtype) = error_mark_node;
4894 arg = DECL_CHAIN (arg);
4895 argtype = TREE_CHAIN (argtype);
4898 /* Check for bare parameter packs in the return type and the
4899 exception specifiers. */
4900 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4901 /* Errors were already issued, set return type to int
4902 as the frontend doesn't expect error_mark_node as
4904 TREE_TYPE (type) = integer_type_node;
4905 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4906 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4908 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4910 TREE_TYPE (decl) = error_mark_node;
4911 return error_mark_node;
4915 return process_partial_specialization (decl);
4917 args = current_template_args ();
4920 || TREE_CODE (ctx) == FUNCTION_DECL
4921 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4922 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4924 if (DECL_LANG_SPECIFIC (decl)
4925 && DECL_TEMPLATE_INFO (decl)
4926 && DECL_TI_TEMPLATE (decl))
4927 tmpl = DECL_TI_TEMPLATE (decl);
4928 /* If DECL is a TYPE_DECL for a class-template, then there won't
4929 be DECL_LANG_SPECIFIC. The information equivalent to
4930 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4931 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4932 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4933 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4935 /* Since a template declaration already existed for this
4936 class-type, we must be redeclaring it here. Make sure
4937 that the redeclaration is valid. */
4938 redeclare_class_template (TREE_TYPE (decl),
4939 current_template_parms);
4940 /* We don't need to create a new TEMPLATE_DECL; just use the
4941 one we already had. */
4942 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4946 tmpl = build_template_decl (decl, current_template_parms,
4950 if (DECL_LANG_SPECIFIC (decl)
4951 && DECL_TEMPLATE_SPECIALIZATION (decl))
4953 /* A specialization of a member template of a template
4955 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4956 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4957 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4963 tree a, t, current, parms;
4965 tree tinfo = get_template_info (decl);
4969 error ("template definition of non-template %q#D", decl);
4970 return error_mark_node;
4973 tmpl = TI_TEMPLATE (tinfo);
4975 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4976 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4977 && DECL_TEMPLATE_SPECIALIZATION (decl)
4978 && DECL_MEMBER_TEMPLATE_P (tmpl))
4982 /* The declaration is a specialization of a member
4983 template, declared outside the class. Therefore, the
4984 innermost template arguments will be NULL, so we
4985 replace them with the arguments determined by the
4986 earlier call to check_explicit_specialization. */
4987 args = DECL_TI_ARGS (decl);
4990 = build_template_decl (decl, current_template_parms,
4992 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4993 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4994 DECL_TI_TEMPLATE (decl) = new_tmpl;
4995 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4996 DECL_TEMPLATE_INFO (new_tmpl)
4997 = build_template_info (tmpl, args);
4999 register_specialization (new_tmpl,
5000 most_general_template (tmpl),
5006 /* Make sure the template headers we got make sense. */
5008 parms = DECL_TEMPLATE_PARMS (tmpl);
5009 i = TMPL_PARMS_DEPTH (parms);
5010 if (TMPL_ARGS_DEPTH (args) != i)
5012 error ("expected %d levels of template parms for %q#D, got %d",
5013 i, decl, TMPL_ARGS_DEPTH (args));
5016 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5018 a = TMPL_ARGS_LEVEL (args, i);
5019 t = INNERMOST_TEMPLATE_PARMS (parms);
5021 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5023 if (current == decl)
5024 error ("got %d template parameters for %q#D",
5025 TREE_VEC_LENGTH (a), decl);
5027 error ("got %d template parameters for %q#T",
5028 TREE_VEC_LENGTH (a), current);
5029 error (" but %d required", TREE_VEC_LENGTH (t));
5030 return error_mark_node;
5033 if (current == decl)
5035 else if (current == NULL_TREE)
5036 /* Can happen in erroneous input. */
5039 current = (TYPE_P (current)
5040 ? TYPE_CONTEXT (current)
5041 : DECL_CONTEXT (current));
5044 /* Check that the parms are used in the appropriate qualifying scopes
5045 in the declarator. */
5046 if (!comp_template_args
5048 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5051 template arguments to %qD do not match original template %qD",
5052 decl, DECL_TEMPLATE_RESULT (tmpl));
5053 if (!uses_template_parms (TI_ARGS (tinfo)))
5054 inform (input_location, "use template<> for an explicit specialization");
5055 /* Avoid crash in import_export_decl. */
5056 DECL_INTERFACE_KNOWN (decl) = 1;
5057 return error_mark_node;
5061 DECL_TEMPLATE_RESULT (tmpl) = decl;
5062 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5064 /* Push template declarations for global functions and types. Note
5065 that we do not try to push a global template friend declared in a
5066 template class; such a thing may well depend on the template
5067 parameters of the class. */
5068 if (new_template_p && !ctx
5069 && !(is_friend && template_class_depth (current_class_type) > 0))
5071 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5072 if (tmpl == error_mark_node)
5073 return error_mark_node;
5075 /* Hide template friend classes that haven't been declared yet. */
5076 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5078 DECL_ANTICIPATED (tmpl) = 1;
5079 DECL_FRIEND_P (tmpl) = 1;
5085 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5088 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5089 if (DECL_CONV_FN_P (tmpl))
5091 int depth = TMPL_PARMS_DEPTH (parms);
5093 /* It is a conversion operator. See if the type converted to
5094 depends on innermost template operands. */
5096 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5098 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5101 /* Give template template parms a DECL_CONTEXT of the template
5102 for which they are a parameter. */
5103 parms = INNERMOST_TEMPLATE_PARMS (parms);
5104 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5106 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5107 if (TREE_CODE (parm) == TEMPLATE_DECL)
5108 DECL_CONTEXT (parm) = tmpl;
5112 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5113 back to its most general template. If TMPL is a specialization,
5114 ARGS may only have the innermost set of arguments. Add the missing
5115 argument levels if necessary. */
5116 if (DECL_TEMPLATE_INFO (tmpl))
5117 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5119 info = build_template_info (tmpl, args);
5121 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5122 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5125 if (primary && !DECL_LANG_SPECIFIC (decl))
5126 retrofit_lang_decl (decl);
5127 if (DECL_LANG_SPECIFIC (decl))
5128 DECL_TEMPLATE_INFO (decl) = info;
5131 return DECL_TEMPLATE_RESULT (tmpl);
5135 push_template_decl (tree decl)
5137 return push_template_decl_real (decl, false);
5140 /* Called when a class template TYPE is redeclared with the indicated
5141 template PARMS, e.g.:
5143 template <class T> struct S;
5144 template <class T> struct S {}; */
5147 redeclare_class_template (tree type, tree parms)
5153 if (!TYPE_TEMPLATE_INFO (type))
5155 error ("%qT is not a template type", type);
5159 tmpl = TYPE_TI_TEMPLATE (type);
5160 if (!PRIMARY_TEMPLATE_P (tmpl))
5161 /* The type is nested in some template class. Nothing to worry
5162 about here; there are no new template parameters for the nested
5168 error ("template specifiers not specified in declaration of %qD",
5173 parms = INNERMOST_TEMPLATE_PARMS (parms);
5174 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5176 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5178 error_n (input_location, TREE_VEC_LENGTH (parms),
5179 "redeclared with %d template parameter",
5180 "redeclared with %d template parameters",
5181 TREE_VEC_LENGTH (parms));
5182 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5183 "previous declaration %q+D used %d template parameter",
5184 "previous declaration %q+D used %d template parameters",
5185 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5189 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5196 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5197 || TREE_VEC_ELT (parms, i) == error_mark_node)
5200 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5201 if (tmpl_parm == error_mark_node)
5204 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5205 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5206 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5208 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5210 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5211 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5212 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5213 || (TREE_CODE (tmpl_parm) != PARM_DECL
5214 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5215 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5216 || (TREE_CODE (tmpl_parm) == PARM_DECL
5217 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5218 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5220 error ("template parameter %q+#D", tmpl_parm);
5221 error ("redeclared here as %q#D", parm);
5225 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5227 /* We have in [temp.param]:
5229 A template-parameter may not be given default arguments
5230 by two different declarations in the same scope. */
5231 error_at (input_location, "redefinition of default argument for %q#D", parm);
5232 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5233 "original definition appeared here");
5237 if (parm_default != NULL_TREE)
5238 /* Update the previous template parameters (which are the ones
5239 that will really count) with the new default value. */
5240 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5241 else if (tmpl_default != NULL_TREE)
5242 /* Update the new parameters, too; they'll be used as the
5243 parameters for any members. */
5244 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5250 /* Simplify EXPR if it is a non-dependent expression. Returns the
5251 (possibly simplified) expression. */
5254 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5256 if (expr == NULL_TREE)
5259 /* If we're in a template, but EXPR isn't value dependent, simplify
5260 it. We're supposed to treat:
5262 template <typename T> void f(T[1 + 1]);
5263 template <typename T> void f(T[2]);
5265 as two declarations of the same function, for example. */
5266 if (processing_template_decl
5267 && !type_dependent_expression_p (expr)
5268 && potential_constant_expression (expr)
5269 && !value_dependent_expression_p (expr))
5271 HOST_WIDE_INT saved_processing_template_decl;
5273 saved_processing_template_decl = processing_template_decl;
5274 processing_template_decl = 0;
5275 expr = tsubst_copy_and_build (expr,
5278 /*in_decl=*/NULL_TREE,
5279 /*function_p=*/false,
5280 /*integral_constant_expression_p=*/true);
5281 processing_template_decl = saved_processing_template_decl;
5287 fold_non_dependent_expr (tree expr)
5289 return fold_non_dependent_expr_sfinae (expr, tf_error);
5292 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5293 template declaration, or a TYPE_DECL for an alias declaration. */
5296 alias_type_or_template_p (tree t)
5300 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5303 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5304 || DECL_ALIAS_TEMPLATE_P (t));
5307 /* Return TRUE iff is a specialization of an alias template. */
5310 alias_template_specialization_p (tree t)
5314 return (primary_template_instantiation_p (t)
5315 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5318 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5319 must be a function or a pointer-to-function type, as specified
5320 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5321 and check that the resulting function has external linkage. */
5324 convert_nontype_argument_function (tree type, tree expr)
5328 linkage_kind linkage;
5330 fn = instantiate_type (type, fns, tf_none);
5331 if (fn == error_mark_node)
5332 return error_mark_node;
5335 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5336 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5337 if (BASELINK_P (fn_no_ptr))
5338 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5340 /* [temp.arg.nontype]/1
5342 A template-argument for a non-type, non-template template-parameter
5345 -- the address of an object or function with external [C++11: or
5346 internal] linkage. */
5347 linkage = decl_linkage (fn_no_ptr);
5348 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5350 if (cxx_dialect >= cxx0x)
5351 error ("%qE is not a valid template argument for type %qT "
5352 "because %qD has no linkage",
5353 expr, type, fn_no_ptr);
5355 error ("%qE is not a valid template argument for type %qT "
5356 "because %qD does not have external linkage",
5357 expr, type, fn_no_ptr);
5364 /* Subroutine of convert_nontype_argument.
5365 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5366 Emit an error otherwise. */
5369 check_valid_ptrmem_cst_expr (tree type, tree expr,
5370 tsubst_flags_t complain)
5373 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5375 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5377 if (complain & tf_error)
5379 error ("%qE is not a valid template argument for type %qT",
5381 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5386 /* Returns TRUE iff the address of OP is value-dependent.
5388 14.6.2.4 [temp.dep.temp]:
5389 A non-integral non-type template-argument is dependent if its type is
5390 dependent or it has either of the following forms
5393 and contains a nested-name-specifier which specifies a class-name that
5394 names a dependent type.
5396 We generalize this to just say that the address of a member of a
5397 dependent class is value-dependent; the above doesn't cover the
5398 address of a static data member named with an unqualified-id. */
5401 has_value_dependent_address (tree op)
5403 /* We could use get_inner_reference here, but there's no need;
5404 this is only relevant for template non-type arguments, which
5405 can only be expressed as &id-expression. */
5408 tree ctx = CP_DECL_CONTEXT (op);
5409 if (TYPE_P (ctx) && dependent_type_p (ctx))
5416 /* The next set of functions are used for providing helpful explanatory
5417 diagnostics for failed overload resolution. Their messages should be
5418 indented by two spaces for consistency with the messages in
5422 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5428 unify_parameter_deduction_failure (bool explain_p, tree parm)
5431 inform (input_location,
5432 " couldn't deduce template parameter %qD", parm);
5437 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5443 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5446 inform (input_location,
5447 " types %qT and %qT have incompatible cv-qualifiers",
5453 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5456 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5461 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5464 inform (input_location,
5465 " template parameter %qD is not a parameter pack, but "
5472 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5475 inform (input_location,
5476 " template argument %qE does not match "
5477 "pointer-to-member constant %qE",
5483 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5486 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5491 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5494 inform (input_location,
5495 " inconsistent parameter pack deduction with %qT and %qT",
5501 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5504 inform (input_location,
5505 " conflicting deductions for parameter %qE (%qE and %qE)",
5506 parm, first, second);
5511 unify_vla_arg (bool explain_p, tree arg)
5514 inform (input_location,
5515 " variable-sized array type %qT is not "
5516 "a valid template argument",
5522 unify_method_type_error (bool explain_p, tree arg)
5525 inform (input_location,
5526 " member function type %qT is not a valid template argument",
5532 unify_arity (bool explain_p, int have, int wanted)
5535 inform_n (input_location, wanted,
5536 " candidate expects %d argument, %d provided",
5537 " candidate expects %d arguments, %d provided",
5543 unify_too_many_arguments (bool explain_p, int have, int wanted)
5545 return unify_arity (explain_p, have, wanted);
5549 unify_too_few_arguments (bool explain_p, int have, int wanted)
5551 return unify_arity (explain_p, have, wanted);
5555 unify_arg_conversion (bool explain_p, tree to_type,
5556 tree from_type, tree arg)
5559 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5560 arg, from_type, to_type);
5565 unify_no_common_base (bool explain_p, enum template_base_result r,
5566 tree parm, tree arg)
5571 case tbr_ambiguous_baseclass:
5572 inform (input_location, " %qT is an ambiguous base class of %qT",
5576 inform (input_location, " %qT is not derived from %qT", arg, parm);
5583 unify_inconsistent_template_template_parameters (bool explain_p)
5586 inform (input_location,
5587 " template parameters of a template template argument are "
5588 "inconsistent with other deduced template arguments");
5593 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5596 inform (input_location,
5597 " can't deduce a template for %qT from non-template type %qT",
5603 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5606 inform (input_location,
5607 " template argument %qE does not match %qD", arg, parm);
5612 unify_overload_resolution_failure (bool explain_p, tree arg)
5615 inform (input_location,
5616 " could not resolve address from overloaded function %qE",
5621 /* Attempt to convert the non-type template parameter EXPR to the
5622 indicated TYPE. If the conversion is successful, return the
5623 converted value. If the conversion is unsuccessful, return
5624 NULL_TREE if we issued an error message, or error_mark_node if we
5625 did not. We issue error messages for out-and-out bad template
5626 parameters, but not simply because the conversion failed, since we
5627 might be just trying to do argument deduction. Both TYPE and EXPR
5628 must be non-dependent.
5630 The conversion follows the special rules described in
5631 [temp.arg.nontype], and it is much more strict than an implicit
5634 This function is called twice for each template argument (see
5635 lookup_template_class for a more accurate description of this
5636 problem). This means that we need to handle expressions which
5637 are not valid in a C++ source, but can be created from the
5638 first call (for instance, casts to perform conversions). These
5639 hacks can go away after we fix the double coercion problem. */
5642 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5646 /* Detect immediately string literals as invalid non-type argument.
5647 This special-case is not needed for correctness (we would easily
5648 catch this later), but only to provide better diagnostic for this
5649 common user mistake. As suggested by DR 100, we do not mention
5650 linkage issues in the diagnostic as this is not the point. */
5651 /* FIXME we're making this OK. */
5652 if (TREE_CODE (expr) == STRING_CST)
5654 if (complain & tf_error)
5655 error ("%qE is not a valid template argument for type %qT "
5656 "because string literals can never be used in this context",
5661 /* Add the ADDR_EXPR now for the benefit of
5662 value_dependent_expression_p. */
5663 if (TYPE_PTROBV_P (type)
5664 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5665 expr = decay_conversion (expr);
5667 /* If we are in a template, EXPR may be non-dependent, but still
5668 have a syntactic, rather than semantic, form. For example, EXPR
5669 might be a SCOPE_REF, rather than the VAR_DECL to which the
5670 SCOPE_REF refers. Preserving the qualifying scope is necessary
5671 so that access checking can be performed when the template is
5672 instantiated -- but here we need the resolved form so that we can
5673 convert the argument. */
5674 if (TYPE_REF_OBJ_P (type)
5675 && has_value_dependent_address (expr))
5676 /* If we want the address and it's value-dependent, don't fold. */;
5677 else if (!type_unknown_p (expr))
5678 expr = fold_non_dependent_expr_sfinae (expr, complain);
5679 if (error_operand_p (expr))
5680 return error_mark_node;
5681 expr_type = TREE_TYPE (expr);
5682 if (TREE_CODE (type) == REFERENCE_TYPE)
5683 expr = mark_lvalue_use (expr);
5685 expr = mark_rvalue_use (expr);
5687 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5688 to a non-type argument of "nullptr". */
5689 if (expr == nullptr_node
5690 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5691 expr = convert (type, expr);
5693 /* In C++11, integral or enumeration non-type template arguments can be
5694 arbitrary constant expressions. Pointer and pointer to
5695 member arguments can be general constant expressions that evaluate
5696 to a null value, but otherwise still need to be of a specific form. */
5697 if (cxx_dialect >= cxx0x)
5699 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5700 expr = maybe_constant_value (expr);
5701 else if (TYPE_PTR_P (type)
5702 || (TYPE_PTR_TO_MEMBER_P (type)
5703 && TREE_CODE (expr) != PTRMEM_CST))
5705 tree folded = maybe_constant_value (expr);
5706 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5707 : null_member_pointer_value_p (folded))
5712 /* HACK: Due to double coercion, we can get a
5713 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5714 which is the tree that we built on the first call (see
5715 below when coercing to reference to object or to reference to
5716 function). We just strip everything and get to the arg.
5717 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5719 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5721 tree probe_type, probe = expr;
5722 if (REFERENCE_REF_P (probe))
5723 probe = TREE_OPERAND (probe, 0);
5724 probe_type = TREE_TYPE (probe);
5725 if (TREE_CODE (probe) == NOP_EXPR)
5727 /* ??? Maybe we could use convert_from_reference here, but we
5728 would need to relax its constraints because the NOP_EXPR
5729 could actually change the type to something more cv-qualified,
5730 and this is not folded by convert_from_reference. */
5731 tree addr = TREE_OPERAND (probe, 0);
5732 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5733 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5734 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5735 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5736 (TREE_TYPE (probe_type),
5737 TREE_TYPE (TREE_TYPE (addr))));
5739 expr = TREE_OPERAND (addr, 0);
5740 expr_type = TREE_TYPE (expr);
5744 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5745 parameter is a pointer to object, through decay and
5746 qualification conversion. Let's strip everything. */
5747 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5750 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5751 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5752 /* Skip the ADDR_EXPR only if it is part of the decay for
5753 an array. Otherwise, it is part of the original argument
5754 in the source code. */
5755 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5756 expr = TREE_OPERAND (expr, 0);
5757 expr_type = TREE_TYPE (expr);
5760 /* [temp.arg.nontype]/5, bullet 1
5762 For a non-type template-parameter of integral or enumeration type,
5763 integral promotions (_conv.prom_) and integral conversions
5764 (_conv.integral_) are applied. */
5765 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5767 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5768 t = maybe_constant_value (t);
5769 if (t != error_mark_node)
5772 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5773 return error_mark_node;
5775 /* Notice that there are constant expressions like '4 % 0' which
5776 do not fold into integer constants. */
5777 if (TREE_CODE (expr) != INTEGER_CST)
5779 if (complain & tf_error)
5781 int errs = errorcount, warns = warningcount;
5782 expr = cxx_constant_value (expr);
5783 if (errorcount > errs || warningcount > warns)
5784 inform (EXPR_LOC_OR_HERE (expr),
5785 "in template argument for type %qT ", type);
5786 if (expr == error_mark_node)
5788 /* else cxx_constant_value complained but gave us
5789 a real constant, so go ahead. */
5790 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5796 /* [temp.arg.nontype]/5, bullet 2
5798 For a non-type template-parameter of type pointer to object,
5799 qualification conversions (_conv.qual_) and the array-to-pointer
5800 conversion (_conv.array_) are applied. */
5801 else if (TYPE_PTROBV_P (type))
5803 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5805 A template-argument for a non-type, non-template template-parameter
5806 shall be one of: [...]
5808 -- the name of a non-type template-parameter;
5809 -- the address of an object or function with external linkage, [...]
5810 expressed as "& id-expression" where the & is optional if the name
5811 refers to a function or array, or if the corresponding
5812 template-parameter is a reference.
5814 Here, we do not care about functions, as they are invalid anyway
5815 for a parameter of type pointer-to-object. */
5817 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5818 /* Non-type template parameters are OK. */
5820 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5821 /* Null pointer values are OK in C++11. */;
5822 else if (TREE_CODE (expr) != ADDR_EXPR
5823 && TREE_CODE (expr_type) != ARRAY_TYPE)
5825 if (TREE_CODE (expr) == VAR_DECL)
5827 error ("%qD is not a valid template argument "
5828 "because %qD is a variable, not the address of "
5833 /* Other values, like integer constants, might be valid
5834 non-type arguments of some other type. */
5835 return error_mark_node;
5841 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5842 ? TREE_OPERAND (expr, 0) : expr);
5843 if (TREE_CODE (decl) != VAR_DECL)
5845 error ("%qE is not a valid template argument of type %qT "
5846 "because %qE is not a variable",
5850 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5852 error ("%qE is not a valid template argument of type %qT "
5853 "because %qD does not have external linkage",
5857 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5859 error ("%qE is not a valid template argument of type %qT "
5860 "because %qD has no linkage",
5866 expr = decay_conversion (expr);
5867 if (expr == error_mark_node)
5868 return error_mark_node;
5870 expr = perform_qualification_conversions (type, expr);
5871 if (expr == error_mark_node)
5872 return error_mark_node;
5874 /* [temp.arg.nontype]/5, bullet 3
5876 For a non-type template-parameter of type reference to object, no
5877 conversions apply. The type referred to by the reference may be more
5878 cv-qualified than the (otherwise identical) type of the
5879 template-argument. The template-parameter is bound directly to the
5880 template-argument, which must be an lvalue. */
5881 else if (TYPE_REF_OBJ_P (type))
5883 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5885 return error_mark_node;
5887 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5889 error ("%qE is not a valid template argument for type %qT "
5890 "because of conflicts in cv-qualification", expr, type);
5894 if (!real_lvalue_p (expr))
5896 error ("%qE is not a valid template argument for type %qT "
5897 "because it is not an lvalue", expr, type);
5901 /* [temp.arg.nontype]/1
5903 A template-argument for a non-type, non-template template-parameter
5904 shall be one of: [...]
5906 -- the address of an object or function with external linkage. */
5907 if (TREE_CODE (expr) == INDIRECT_REF
5908 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5910 expr = TREE_OPERAND (expr, 0);
5913 error ("%q#D is not a valid template argument for type %qT "
5914 "because a reference variable does not have a constant "
5915 "address", expr, type);
5922 error ("%qE is not a valid template argument for type %qT "
5923 "because it is not an object with external linkage",
5928 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5930 error ("%qE is not a valid template argument for type %qT "
5931 "because object %qD has not external linkage",
5936 expr = build_nop (type, build_address (expr));
5938 /* [temp.arg.nontype]/5, bullet 4
5940 For a non-type template-parameter of type pointer to function, only
5941 the function-to-pointer conversion (_conv.func_) is applied. If the
5942 template-argument represents a set of overloaded functions (or a
5943 pointer to such), the matching function is selected from the set
5945 else if (TYPE_PTRFN_P (type))
5947 /* If the argument is a template-id, we might not have enough
5948 context information to decay the pointer. */
5949 if (!type_unknown_p (expr_type))
5951 expr = decay_conversion (expr);
5952 if (expr == error_mark_node)
5953 return error_mark_node;
5956 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5957 /* Null pointer values are OK in C++11. */
5958 return perform_qualification_conversions (type, expr);
5960 expr = convert_nontype_argument_function (type, expr);
5961 if (!expr || expr == error_mark_node)
5964 if (TREE_CODE (expr) != ADDR_EXPR)
5966 error ("%qE is not a valid template argument for type %qT", expr, type);
5967 error ("it must be the address of a function with external linkage");
5971 /* [temp.arg.nontype]/5, bullet 5
5973 For a non-type template-parameter of type reference to function, no
5974 conversions apply. If the template-argument represents a set of
5975 overloaded functions, the matching function is selected from the set
5977 else if (TYPE_REFFN_P (type))
5979 if (TREE_CODE (expr) == ADDR_EXPR)
5981 error ("%qE is not a valid template argument for type %qT "
5982 "because it is a pointer", expr, type);
5983 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5987 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5988 if (!expr || expr == error_mark_node)
5991 expr = build_nop (type, build_address (expr));
5993 /* [temp.arg.nontype]/5, bullet 6
5995 For a non-type template-parameter of type pointer to member function,
5996 no conversions apply. If the template-argument represents a set of
5997 overloaded member functions, the matching member function is selected
5998 from the set (_over.over_). */
5999 else if (TYPE_PTRMEMFUNC_P (type))
6001 expr = instantiate_type (type, expr, tf_none);
6002 if (expr == error_mark_node)
6003 return error_mark_node;
6005 /* [temp.arg.nontype] bullet 1 says the pointer to member
6006 expression must be a pointer-to-member constant. */
6007 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6008 return error_mark_node;
6010 /* There is no way to disable standard conversions in
6011 resolve_address_of_overloaded_function (called by
6012 instantiate_type). It is possible that the call succeeded by
6013 converting &B::I to &D::I (where B is a base of D), so we need
6014 to reject this conversion here.
6016 Actually, even if there was a way to disable standard conversions,
6017 it would still be better to reject them here so that we can
6018 provide a superior diagnostic. */
6019 if (!same_type_p (TREE_TYPE (expr), type))
6021 error ("%qE is not a valid template argument for type %qT "
6022 "because it is of type %qT", expr, type,
6024 /* If we are just one standard conversion off, explain. */
6025 if (can_convert (type, TREE_TYPE (expr)))
6026 inform (input_location,
6027 "standard conversions are not allowed in this context");
6031 /* [temp.arg.nontype]/5, bullet 7
6033 For a non-type template-parameter of type pointer to data member,
6034 qualification conversions (_conv.qual_) are applied. */
6035 else if (TYPE_PTRMEM_P (type))
6037 /* [temp.arg.nontype] bullet 1 says the pointer to member
6038 expression must be a pointer-to-member constant. */
6039 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6040 return error_mark_node;
6042 expr = perform_qualification_conversions (type, expr);
6043 if (expr == error_mark_node)
6046 else if (NULLPTR_TYPE_P (type))
6048 if (expr != nullptr_node)
6050 error ("%qE is not a valid template argument for type %qT "
6051 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6056 /* A template non-type parameter must be one of the above. */
6060 /* Sanity check: did we actually convert the argument to the
6062 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6063 (type, TREE_TYPE (expr)));
6067 /* Subroutine of coerce_template_template_parms, which returns 1 if
6068 PARM_PARM and ARG_PARM match using the rule for the template
6069 parameters of template template parameters. Both PARM and ARG are
6070 template parameters; the rest of the arguments are the same as for
6071 coerce_template_template_parms.
6074 coerce_template_template_parm (tree parm,
6076 tsubst_flags_t complain,
6080 if (arg == NULL_TREE || arg == error_mark_node
6081 || parm == NULL_TREE || parm == error_mark_node)
6084 if (TREE_CODE (arg) != TREE_CODE (parm))
6087 switch (TREE_CODE (parm))
6090 /* We encounter instantiations of templates like
6091 template <template <template <class> class> class TT>
6094 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6095 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6097 if (!coerce_template_template_parms
6098 (parmparm, argparm, complain, in_decl, outer_args))
6104 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6105 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6106 /* Argument is a parameter pack but parameter is not. */
6111 /* The tsubst call is used to handle cases such as
6113 template <int> class C {};
6114 template <class T, template <T> class TT> class D {};
6117 i.e. the parameter list of TT depends on earlier parameters. */
6118 if (!uses_template_parms (TREE_TYPE (arg))
6120 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6124 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6125 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6126 /* Argument is a parameter pack but parameter is not. */
6139 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6140 template template parameters. Both PARM_PARMS and ARG_PARMS are
6141 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6144 Consider the example:
6145 template <class T> class A;
6146 template<template <class U> class TT> class B;
6148 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6149 the parameters to A, and OUTER_ARGS contains A. */
6152 coerce_template_template_parms (tree parm_parms,
6154 tsubst_flags_t complain,
6158 int nparms, nargs, i;
6162 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6163 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6165 nparms = TREE_VEC_LENGTH (parm_parms);
6166 nargs = TREE_VEC_LENGTH (arg_parms);
6168 /* Determine whether we have a parameter pack at the end of the
6169 template template parameter's template parameter list. */
6170 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6172 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6174 if (parm == error_mark_node)
6177 switch (TREE_CODE (parm))
6181 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6186 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6196 && !(variadic_p && nargs >= nparms - 1))
6199 /* Check all of the template parameters except the parameter pack at
6200 the end (if any). */
6201 for (i = 0; i < nparms - variadic_p; ++i)
6203 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6204 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6207 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6208 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6210 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6218 /* Check each of the template parameters in the template
6219 argument against the template parameter pack at the end of
6220 the template template parameter. */
6221 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6224 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6226 for (; i < nargs; ++i)
6228 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6231 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6233 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6242 /* Verifies that the deduced template arguments (in TARGS) for the
6243 template template parameters (in TPARMS) represent valid bindings,
6244 by comparing the template parameter list of each template argument
6245 to the template parameter list of its corresponding template
6246 template parameter, in accordance with DR150. This
6247 routine can only be called after all template arguments have been
6248 deduced. It will return TRUE if all of the template template
6249 parameter bindings are okay, FALSE otherwise. */
6251 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6253 int i, ntparms = TREE_VEC_LENGTH (tparms);
6256 /* We're dealing with template parms in this process. */
6257 ++processing_template_decl;
6259 targs = INNERMOST_TEMPLATE_ARGS (targs);
6261 for (i = 0; i < ntparms; ++i)
6263 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6264 tree targ = TREE_VEC_ELT (targs, i);
6266 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6268 tree packed_args = NULL_TREE;
6271 if (ARGUMENT_PACK_P (targ))
6273 /* Look inside the argument pack. */
6274 packed_args = ARGUMENT_PACK_ARGS (targ);
6275 len = TREE_VEC_LENGTH (packed_args);
6278 for (idx = 0; idx < len; ++idx)
6280 tree targ_parms = NULL_TREE;
6283 /* Extract the next argument from the argument
6285 targ = TREE_VEC_ELT (packed_args, idx);
6287 if (PACK_EXPANSION_P (targ))
6288 /* Look at the pattern of the pack expansion. */
6289 targ = PACK_EXPANSION_PATTERN (targ);
6291 /* Extract the template parameters from the template
6293 if (TREE_CODE (targ) == TEMPLATE_DECL)
6294 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6295 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6296 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6298 /* Verify that we can coerce the template template
6299 parameters from the template argument to the template
6300 parameter. This requires an exact match. */
6302 && !coerce_template_template_parms
6303 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6318 --processing_template_decl;
6322 /* Since type attributes aren't mangled, we need to strip them from
6323 template type arguments. */
6326 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6329 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6331 mv = TYPE_MAIN_VARIANT (arg);
6332 arg = strip_typedefs (arg);
6333 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6334 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6336 if (complain & tf_warning)
6337 warning (0, "ignoring attributes on template argument %qT", arg);
6338 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6339 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6344 /* Convert the indicated template ARG as necessary to match the
6345 indicated template PARM. Returns the converted ARG, or
6346 error_mark_node if the conversion was unsuccessful. Error and
6347 warning messages are issued under control of COMPLAIN. This
6348 conversion is for the Ith parameter in the parameter list. ARGS is
6349 the full set of template arguments deduced so far. */
6352 convert_template_argument (tree parm,
6355 tsubst_flags_t complain,
6361 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6363 if (TREE_CODE (arg) == TREE_LIST
6364 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6366 /* The template argument was the name of some
6367 member function. That's usually
6368 invalid, but static members are OK. In any
6369 case, grab the underlying fields/functions
6370 and issue an error later if required. */
6371 orig_arg = TREE_VALUE (arg);
6372 TREE_TYPE (arg) = unknown_type_node;
6377 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6378 requires_type = (TREE_CODE (parm) == TYPE_DECL
6379 || requires_tmpl_type);
6381 /* When determining whether an argument pack expansion is a template,
6382 look at the pattern. */
6383 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6384 arg = PACK_EXPANSION_PATTERN (arg);
6386 /* Deal with an injected-class-name used as a template template arg. */
6387 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6389 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6390 if (TREE_CODE (t) == TEMPLATE_DECL)
6392 if (cxx_dialect >= cxx0x)
6393 /* OK under DR 1004. */;
6394 else if (complain & tf_warning_or_error)
6395 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6396 " used as template template argument", TYPE_NAME (arg));
6397 else if (flag_pedantic_errors)
6405 ((TREE_CODE (arg) == TEMPLATE_DECL
6406 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6407 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6408 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6411 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6412 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6413 arg = TYPE_STUB_DECL (arg);
6415 is_type = TYPE_P (arg) || is_tmpl_type;
6417 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6418 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6420 permerror (input_location, "to refer to a type member of a template parameter, "
6421 "use %<typename %E%>", orig_arg);
6423 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6424 TREE_OPERAND (arg, 1),
6426 complain & tf_error);
6430 if (is_type != requires_type)
6434 if (complain & tf_error)
6436 error ("type/value mismatch at argument %d in template "
6437 "parameter list for %qD",
6440 error (" expected a constant of type %qT, got %qT",
6442 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6443 else if (requires_tmpl_type)
6444 error (" expected a class template, got %qE", orig_arg);
6446 error (" expected a type, got %qE", orig_arg);
6449 return error_mark_node;
6451 if (is_tmpl_type ^ requires_tmpl_type)
6453 if (in_decl && (complain & tf_error))
6455 error ("type/value mismatch at argument %d in template "
6456 "parameter list for %qD",
6459 error (" expected a type, got %qT", DECL_NAME (arg));
6461 error (" expected a class template, got %qT", orig_arg);
6463 return error_mark_node;
6468 if (requires_tmpl_type)
6470 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6471 /* The number of argument required is not known yet.
6472 Just accept it for now. */
6473 val = TREE_TYPE (arg);
6476 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6479 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6481 if (coerce_template_template_parms (parmparm, argparm,
6487 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6489 if (val != error_mark_node)
6491 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6492 val = TREE_TYPE (val);
6493 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6494 val = make_pack_expansion (val);
6499 if (in_decl && (complain & tf_error))
6501 error ("type/value mismatch at argument %d in "
6502 "template parameter list for %qD",
6504 error (" expected a template of type %qD, got %qT",
6508 val = error_mark_node;
6514 /* We only form one instance of each template specialization.
6515 Therefore, if we use a non-canonical variant (i.e., a
6516 typedef), any future messages referring to the type will use
6517 the typedef, which is confusing if those future uses do not
6518 themselves also use the typedef. */
6520 val = canonicalize_type_argument (val, complain);
6524 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6526 if (invalid_nontype_parm_type_p (t, complain))
6527 return error_mark_node;
6529 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6531 if (same_type_p (t, TREE_TYPE (orig_arg)))
6535 /* Not sure if this is reachable, but it doesn't hurt
6537 error ("type mismatch in nontype parameter pack");
6538 val = error_mark_node;
6541 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6542 /* We used to call digest_init here. However, digest_init
6543 will report errors, which we don't want when complain
6544 is zero. More importantly, digest_init will try too
6545 hard to convert things: for example, `0' should not be
6546 converted to pointer type at this point according to
6547 the standard. Accepting this is not merely an
6548 extension, since deciding whether or not these
6549 conversions can occur is part of determining which
6550 function template to call, or whether a given explicit
6551 argument specification is valid. */
6552 val = convert_nontype_argument (t, orig_arg, complain);
6556 if (val == NULL_TREE)
6557 val = error_mark_node;
6558 else if (val == error_mark_node && (complain & tf_error))
6559 error ("could not convert template argument %qE to %qT", orig_arg, t);
6561 if (TREE_CODE (val) == SCOPE_REF)
6563 /* Strip typedefs from the SCOPE_REF. */
6564 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6565 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6567 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6568 QUALIFIED_NAME_IS_TEMPLATE (val));
6575 /* Coerces the remaining template arguments in INNER_ARGS (from
6576 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6577 Returns the coerced argument pack. PARM_IDX is the position of this
6578 parameter in the template parameter list. ARGS is the original
6579 template argument list. */
6581 coerce_template_parameter_pack (tree parms,
6589 tsubst_flags_t complain)
6591 tree parm = TREE_VEC_ELT (parms, parm_idx);
6592 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6595 tree packed_types = NULL_TREE;
6597 if (arg_idx > nargs)
6600 packed_args = make_tree_vec (nargs - arg_idx);
6602 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6603 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6605 /* When the template parameter is a non-type template
6606 parameter pack whose type uses parameter packs, we need
6607 to look at each of the template arguments
6608 separately. Build a vector of the types for these
6609 non-type template parameters in PACKED_TYPES. */
6611 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6612 packed_types = tsubst_pack_expansion (expansion, args,
6615 if (packed_types == error_mark_node)
6616 return error_mark_node;
6618 /* Check that we have the right number of arguments. */
6620 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6621 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6624 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6625 error ("wrong number of template arguments (%d, should be %d)",
6626 nargs, needed_parms);
6627 return error_mark_node;
6630 /* If we aren't able to check the actual arguments now
6631 (because they haven't been expanded yet), we can at least
6632 verify that all of the types used for the non-type
6633 template parameter pack are, in fact, valid for non-type
6634 template parameters. */
6636 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6638 int j, len = TREE_VEC_LENGTH (packed_types);
6639 for (j = 0; j < len; ++j)
6641 tree t = TREE_VEC_ELT (packed_types, j);
6642 if (invalid_nontype_parm_type_p (t, complain))
6643 return error_mark_node;
6648 /* Convert the remaining arguments, which will be a part of the
6649 parameter pack "parm". */
6650 for (; arg_idx < nargs; ++arg_idx)
6652 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6653 tree actual_parm = TREE_VALUE (parm);
6655 if (packed_types && !PACK_EXPANSION_P (arg))
6657 /* When we have a vector of types (corresponding to the
6658 non-type template parameter pack that uses parameter
6659 packs in its type, as mention above), and the
6660 argument is not an expansion (which expands to a
6661 currently unknown number of arguments), clone the
6662 parm and give it the next type in PACKED_TYPES. */
6663 actual_parm = copy_node (actual_parm);
6664 TREE_TYPE (actual_parm) =
6665 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6668 if (arg != error_mark_node)
6669 arg = convert_template_argument (actual_parm,
6670 arg, new_args, complain, parm_idx,
6672 if (arg == error_mark_node)
6674 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6677 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6678 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6679 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6682 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6683 TREE_TYPE (argument_pack)
6684 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6685 TREE_CONSTANT (argument_pack) = 1;
6688 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6689 #ifdef ENABLE_CHECKING
6690 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6691 TREE_VEC_LENGTH (packed_args));
6693 return argument_pack;
6696 /* Convert all template arguments to their appropriate types, and
6697 return a vector containing the innermost resulting template
6698 arguments. If any error occurs, return error_mark_node. Error and
6699 warning messages are issued under control of COMPLAIN.
6701 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6702 for arguments not specified in ARGS. Otherwise, if
6703 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6704 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6705 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6709 coerce_template_parms (tree parms,
6712 tsubst_flags_t complain,
6713 bool require_all_args,
6714 bool use_default_args)
6716 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6719 tree new_inner_args;
6720 int saved_unevaluated_operand;
6721 int saved_inhibit_evaluation_warnings;
6723 /* When used as a boolean value, indicates whether this is a
6724 variadic template parameter list. Since it's an int, we can also
6725 subtract it from nparms to get the number of non-variadic
6728 int post_variadic_parms = 0;
6730 if (args == error_mark_node)
6731 return error_mark_node;
6733 nparms = TREE_VEC_LENGTH (parms);
6735 /* Determine if there are any parameter packs. */
6736 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6738 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6740 ++post_variadic_parms;
6741 if (template_parameter_pack_p (tparm))
6745 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6746 /* If there are no parameters that follow a parameter pack, we need to
6747 expand any argument packs so that we can deduce a parameter pack from
6748 some non-packed args followed by an argument pack, as in variadic85.C.
6749 If there are such parameters, we need to leave argument packs intact
6750 so the arguments are assigned properly. This can happen when dealing
6751 with a nested class inside a partial specialization of a class
6752 template, as in variadic92.C, or when deducing a template parameter pack
6753 from a sub-declarator, as in variadic114.C. */
6754 if (!post_variadic_parms)
6755 inner_args = expand_template_argument_pack (inner_args);
6757 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6758 if ((nargs > nparms && !variadic_p)
6759 || (nargs < nparms - variadic_p
6761 && (!use_default_args
6762 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6763 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6765 if (complain & tf_error)
6769 nparms -= variadic_p;
6770 error ("wrong number of template arguments "
6771 "(%d, should be %d or more)", nargs, nparms);
6774 error ("wrong number of template arguments "
6775 "(%d, should be %d)", nargs, nparms);
6778 error ("provided for %q+D", in_decl);
6781 return error_mark_node;
6784 /* We need to evaluate the template arguments, even though this
6785 template-id may be nested within a "sizeof". */
6786 saved_unevaluated_operand = cp_unevaluated_operand;
6787 cp_unevaluated_operand = 0;
6788 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6789 c_inhibit_evaluation_warnings = 0;
6790 new_inner_args = make_tree_vec (nparms);
6791 new_args = add_outermost_template_args (args, new_inner_args);
6792 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6797 /* Get the Ith template parameter. */
6798 parm = TREE_VEC_ELT (parms, parm_idx);
6800 if (parm == error_mark_node)
6802 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6806 /* Calculate the next argument. */
6807 if (arg_idx < nargs)
6808 arg = TREE_VEC_ELT (inner_args, arg_idx);
6812 if (template_parameter_pack_p (TREE_VALUE (parm))
6813 && !(arg && ARGUMENT_PACK_P (arg)))
6815 /* All remaining arguments will be placed in the
6816 template parameter pack PARM. */
6817 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6818 inner_args, arg_idx,
6822 /* Store this argument. */
6823 if (arg == error_mark_node)
6825 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6827 /* We are done with all of the arguments. */
6834 if (PACK_EXPANSION_P (arg))
6836 /* We don't know how many args we have yet, just
6837 use the unconverted ones for now. */
6838 new_inner_args = args;
6842 else if (require_all_args)
6844 /* There must be a default arg in this case. */
6845 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6847 /* The position of the first default template argument,
6848 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6850 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6851 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6856 if (arg == error_mark_node)
6858 if (complain & tf_error)
6859 error ("template argument %d is invalid", arg_idx + 1);
6862 /* This only occurs if there was an error in the template
6863 parameter list itself (which we would already have
6864 reported) that we are trying to recover from, e.g., a class
6865 template with a parameter list such as
6866 template<typename..., typename>. */
6869 arg = convert_template_argument (TREE_VALUE (parm),
6870 arg, new_args, complain,
6873 if (arg == error_mark_node)
6875 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6877 cp_unevaluated_operand = saved_unevaluated_operand;
6878 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6881 return error_mark_node;
6883 #ifdef ENABLE_CHECKING
6884 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6885 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6886 TREE_VEC_LENGTH (new_inner_args));
6889 return new_inner_args;
6892 /* Returns 1 if template args OT and NT are equivalent. */
6895 template_args_equal (tree ot, tree nt)
6899 if (nt == NULL_TREE || ot == NULL_TREE)
6902 if (TREE_CODE (nt) == TREE_VEC)
6903 /* For member templates */
6904 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6905 else if (PACK_EXPANSION_P (ot))
6906 return (PACK_EXPANSION_P (nt)
6907 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6908 PACK_EXPANSION_PATTERN (nt))
6909 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6910 PACK_EXPANSION_EXTRA_ARGS (nt)));
6911 else if (ARGUMENT_PACK_P (ot))
6916 if (!ARGUMENT_PACK_P (nt))
6919 opack = ARGUMENT_PACK_ARGS (ot);
6920 npack = ARGUMENT_PACK_ARGS (nt);
6921 len = TREE_VEC_LENGTH (opack);
6922 if (TREE_VEC_LENGTH (npack) != len)
6924 for (i = 0; i < len; ++i)
6925 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6926 TREE_VEC_ELT (npack, i)))
6930 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6932 /* We get here probably because we are in the middle of substituting
6933 into the pattern of a pack expansion. In that case the
6934 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6935 interested in. So we want to use the initial pack argument for
6937 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6938 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6939 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6940 return template_args_equal (ot, nt);
6942 else if (TYPE_P (nt))
6943 return TYPE_P (ot) && same_type_p (ot, nt);
6944 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6947 return cp_tree_equal (ot, nt);
6950 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6951 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6952 NEWARG_PTR with the offending arguments if they are non-NULL. */
6955 comp_template_args_with_info (tree oldargs, tree newargs,
6956 tree *oldarg_ptr, tree *newarg_ptr)
6960 if (oldargs == newargs)
6963 if (!oldargs || !newargs)
6966 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6969 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6971 tree nt = TREE_VEC_ELT (newargs, i);
6972 tree ot = TREE_VEC_ELT (oldargs, i);
6974 if (! template_args_equal (ot, nt))
6976 if (oldarg_ptr != NULL)
6978 if (newarg_ptr != NULL)
6986 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6987 of template arguments. Returns 0 otherwise. */
6990 comp_template_args (tree oldargs, tree newargs)
6992 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
6996 add_pending_template (tree d)
6998 tree ti = (TYPE_P (d)
6999 ? CLASSTYPE_TEMPLATE_INFO (d)
7000 : DECL_TEMPLATE_INFO (d));
7001 struct pending_template *pt;
7004 if (TI_PENDING_TEMPLATE_FLAG (ti))
7007 /* We are called both from instantiate_decl, where we've already had a
7008 tinst_level pushed, and instantiate_template, where we haven't.
7010 level = !current_tinst_level || current_tinst_level->decl != d;
7013 push_tinst_level (d);
7015 pt = ggc_alloc_pending_template ();
7017 pt->tinst = current_tinst_level;
7018 if (last_pending_template)
7019 last_pending_template->next = pt;
7021 pending_templates = pt;
7023 last_pending_template = pt;
7025 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7032 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7033 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7034 documentation for TEMPLATE_ID_EXPR. */
7037 lookup_template_function (tree fns, tree arglist)
7041 if (fns == error_mark_node || arglist == error_mark_node)
7042 return error_mark_node;
7044 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7046 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7048 error ("%q#D is not a function template", fns);
7049 return error_mark_node;
7052 if (BASELINK_P (fns))
7054 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7056 BASELINK_FUNCTIONS (fns),
7061 type = TREE_TYPE (fns);
7062 if (TREE_CODE (fns) == OVERLOAD || !type)
7063 type = unknown_type_node;
7065 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7068 /* Within the scope of a template class S<T>, the name S gets bound
7069 (in build_self_reference) to a TYPE_DECL for the class, not a
7070 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7071 or one of its enclosing classes, and that type is a template,
7072 return the associated TEMPLATE_DECL. Otherwise, the original
7075 Also handle the case when DECL is a TREE_LIST of ambiguous
7076 injected-class-names from different bases. */
7079 maybe_get_template_decl_from_type_decl (tree decl)
7081 if (decl == NULL_TREE)
7084 /* DR 176: A lookup that finds an injected-class-name (10.2
7085 [class.member.lookup]) can result in an ambiguity in certain cases
7086 (for example, if it is found in more than one base class). If all of
7087 the injected-class-names that are found refer to specializations of
7088 the same class template, and if the name is followed by a
7089 template-argument-list, the reference refers to the class template
7090 itself and not a specialization thereof, and is not ambiguous. */
7091 if (TREE_CODE (decl) == TREE_LIST)
7093 tree t, tmpl = NULL_TREE;
7094 for (t = decl; t; t = TREE_CHAIN (t))
7096 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7099 else if (tmpl != elt)
7102 if (tmpl && t == NULL_TREE)
7108 return (decl != NULL_TREE
7109 && DECL_SELF_REFERENCE_P (decl)
7110 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7111 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7114 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7115 parameters, find the desired type.
7117 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7119 IN_DECL, if non-NULL, is the template declaration we are trying to
7122 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7123 the class we are looking up.
7125 Issue error and warning messages under control of COMPLAIN.
7127 If the template class is really a local class in a template
7128 function, then the FUNCTION_CONTEXT is the function in which it is
7131 ??? Note that this function is currently called *twice* for each
7132 template-id: the first time from the parser, while creating the
7133 incomplete type (finish_template_type), and the second type during the
7134 real instantiation (instantiate_template_class). This is surely something
7135 that we want to avoid. It also causes some problems with argument
7136 coercion (see convert_nontype_argument for more information on this). */
7139 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7140 int entering_scope, tsubst_flags_t complain)
7142 tree templ = NULL_TREE, parmlist;
7149 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7151 tree value = innermost_non_namespace_value (d1);
7152 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7157 push_decl_namespace (context);
7158 templ = lookup_name (d1);
7159 templ = maybe_get_template_decl_from_type_decl (templ);
7161 pop_decl_namespace ();
7164 context = DECL_CONTEXT (templ);
7166 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7168 tree type = TREE_TYPE (d1);
7170 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7171 an implicit typename for the second A. Deal with it. */
7172 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7173 type = TREE_TYPE (type);
7175 if (CLASSTYPE_TEMPLATE_INFO (type))
7177 templ = CLASSTYPE_TI_TEMPLATE (type);
7178 d1 = DECL_NAME (templ);
7181 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7182 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7184 templ = TYPE_TI_TEMPLATE (d1);
7185 d1 = DECL_NAME (templ);
7187 else if (TREE_CODE (d1) == TEMPLATE_DECL
7188 && DECL_TEMPLATE_RESULT (d1)
7189 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7192 d1 = DECL_NAME (templ);
7193 context = DECL_CONTEXT (templ);
7196 /* Issue an error message if we didn't find a template. */
7199 if (complain & tf_error)
7200 error ("%qT is not a template", d1);
7201 return error_mark_node;
7204 if (TREE_CODE (templ) != TEMPLATE_DECL
7205 /* Make sure it's a user visible template, if it was named by
7207 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7208 && !PRIMARY_TEMPLATE_P (templ)))
7210 if (complain & tf_error)
7212 error ("non-template type %qT used as a template", d1);
7214 error ("for template declaration %q+D", in_decl);
7216 return error_mark_node;
7219 complain &= ~tf_user;
7221 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7223 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7224 template arguments */
7230 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7232 /* Consider an example where a template template parameter declared as
7234 template <class T, class U = std::allocator<T> > class TT
7236 The template parameter level of T and U are one level larger than
7237 of TT. To proper process the default argument of U, say when an
7238 instantiation `TT<int>' is seen, we need to build the full
7239 arguments containing {int} as the innermost level. Outer levels,
7240 available when not appearing as default template argument, can be
7241 obtained from the arguments of the enclosing template.
7243 Suppose that TT is later substituted with std::vector. The above
7244 instantiation is `TT<int, std::allocator<T> >' with TT at
7245 level 1, and T at level 2, while the template arguments at level 1
7246 becomes {std::vector} and the inner level 2 is {int}. */
7248 outer = DECL_CONTEXT (templ);
7250 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7251 else if (current_template_parms)
7252 /* This is an argument of the current template, so we haven't set
7253 DECL_CONTEXT yet. */
7254 outer = current_template_args ();
7257 arglist = add_to_template_args (outer, arglist);
7259 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7261 /*require_all_args=*/true,
7262 /*use_default_args=*/true);
7263 if (arglist2 == error_mark_node
7264 || (!uses_template_parms (arglist2)
7265 && check_instantiated_args (templ, arglist2, complain)))
7266 return error_mark_node;
7268 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7273 tree template_type = TREE_TYPE (templ);
7276 tree found = NULL_TREE;
7279 int is_dependent_type;
7280 int use_partial_inst_tmpl = false;
7282 if (template_type == error_mark_node)
7283 /* An error occured while building the template TEMPL, and a
7284 diagnostic has most certainly been emitted for that
7285 already. Let's propagate that error. */
7286 return error_mark_node;
7288 gen_tmpl = most_general_template (templ);
7289 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7290 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7291 arg_depth = TMPL_ARGS_DEPTH (arglist);
7293 if (arg_depth == 1 && parm_depth > 1)
7295 /* We've been given an incomplete set of template arguments.
7298 template <class T> struct S1 {
7299 template <class U> struct S2 {};
7300 template <class U> struct S2<U*> {};
7303 we will be called with an ARGLIST of `U*', but the
7304 TEMPLATE will be `template <class T> template
7305 <class U> struct S1<T>::S2'. We must fill in the missing
7308 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7310 arg_depth = TMPL_ARGS_DEPTH (arglist);
7313 /* Now we should have enough arguments. */
7314 gcc_assert (parm_depth == arg_depth);
7316 /* From here on, we're only interested in the most general
7319 /* Calculate the BOUND_ARGS. These will be the args that are
7320 actually tsubst'd into the definition to create the
7324 /* We have multiple levels of arguments to coerce, at once. */
7326 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7328 tree bound_args = make_tree_vec (parm_depth);
7330 for (i = saved_depth,
7331 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7332 i > 0 && t != NULL_TREE;
7333 --i, t = TREE_CHAIN (t))
7336 if (i == saved_depth)
7337 a = coerce_template_parms (TREE_VALUE (t),
7340 /*require_all_args=*/true,
7341 /*use_default_args=*/true);
7343 /* Outer levels should have already been coerced. */
7344 a = TMPL_ARGS_LEVEL (arglist, i);
7346 /* Don't process further if one of the levels fails. */
7347 if (a == error_mark_node)
7349 /* Restore the ARGLIST to its full size. */
7350 TREE_VEC_LENGTH (arglist) = saved_depth;
7351 return error_mark_node;
7354 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7356 /* We temporarily reduce the length of the ARGLIST so
7357 that coerce_template_parms will see only the arguments
7358 corresponding to the template parameters it is
7360 TREE_VEC_LENGTH (arglist)--;
7363 /* Restore the ARGLIST to its full size. */
7364 TREE_VEC_LENGTH (arglist) = saved_depth;
7366 arglist = bound_args;
7370 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7371 INNERMOST_TEMPLATE_ARGS (arglist),
7374 /*require_all_args=*/true,
7375 /*use_default_args=*/true);
7377 if (arglist == error_mark_node)
7378 /* We were unable to bind the arguments. */
7379 return error_mark_node;
7381 /* In the scope of a template class, explicit references to the
7382 template class refer to the type of the template, not any
7383 instantiation of it. For example, in:
7385 template <class T> class C { void f(C<T>); }
7387 the `C<T>' is just the same as `C'. Outside of the
7388 class, however, such a reference is an instantiation. */
7390 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7391 || currently_open_class (template_type))
7392 /* comp_template_args is expensive, check it last. */
7393 && comp_template_args (TYPE_TI_ARGS (template_type),
7395 return template_type;
7397 /* If we already have this specialization, return it. */
7398 elt.tmpl = gen_tmpl;
7400 hash = hash_specialization (&elt);
7401 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7407 is_dependent_type = uses_template_parms (arglist);
7409 /* If the deduced arguments are invalid, then the binding
7411 if (!is_dependent_type
7412 && check_instantiated_args (gen_tmpl,
7413 INNERMOST_TEMPLATE_ARGS (arglist),
7415 return error_mark_node;
7417 if (!is_dependent_type
7418 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7419 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7420 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7422 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7423 DECL_NAME (gen_tmpl),
7424 /*tag_scope=*/ts_global);
7428 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7431 context = global_namespace;
7433 /* Create the type. */
7434 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7436 if (!is_dependent_type)
7438 set_current_access_from_decl (TYPE_NAME (template_type));
7439 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7440 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7441 arglist, complain, in_decl),
7442 SCOPED_ENUM_P (template_type), NULL);
7446 /* We don't want to call start_enum for this type, since
7447 the values for the enumeration constants may involve
7448 template parameters. And, no one should be interested
7449 in the enumeration constants for such a type. */
7450 t = cxx_make_type (ENUMERAL_TYPE);
7451 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7453 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7454 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7455 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7457 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7459 /* The user referred to a specialization of an alias
7460 template represented by GEN_TMPL.
7462 [temp.alias]/2 says:
7464 When a template-id refers to the specialization of an
7465 alias template, it is equivalent to the associated
7466 type obtained by substitution of its
7467 template-arguments for the template-parameters in the
7468 type-id of the alias template. */
7470 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7471 /* Note that the call above (by indirectly calling
7472 register_specialization in tsubst_decl) registers the
7473 TYPE_DECL representing the specialization of the alias
7474 template. So next time someone substitutes ARGLIST for
7475 the template parms into the alias template (GEN_TMPL),
7476 she'll get that TYPE_DECL back. */
7478 if (t == error_mark_node)
7481 else if (CLASS_TYPE_P (template_type))
7483 t = make_class_type (TREE_CODE (template_type));
7484 CLASSTYPE_DECLARED_CLASS (t)
7485 = CLASSTYPE_DECLARED_CLASS (template_type);
7486 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7487 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7489 /* A local class. Make sure the decl gets registered properly. */
7490 if (context == current_function_decl)
7491 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7493 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7494 /* This instantiation is another name for the primary
7495 template type. Set the TYPE_CANONICAL field
7497 TYPE_CANONICAL (t) = template_type;
7498 else if (any_template_arguments_need_structural_equality_p (arglist))
7499 /* Some of the template arguments require structural
7500 equality testing, so this template class requires
7501 structural equality testing. */
7502 SET_TYPE_STRUCTURAL_EQUALITY (t);
7507 /* If we called start_enum or pushtag above, this information
7508 will already be set up. */
7511 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7513 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7514 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7515 DECL_SOURCE_LOCATION (type_decl)
7516 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7519 type_decl = TYPE_NAME (t);
7521 if (CLASS_TYPE_P (template_type))
7523 TREE_PRIVATE (type_decl)
7524 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7525 TREE_PROTECTED (type_decl)
7526 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7527 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7529 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7530 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7534 /* Let's consider the explicit specialization of a member
7535 of a class template specialization that is implicitely instantiated,
7540 template<class U> struct M {}; //#0
7545 struct S<int>::M<char> //#1
7549 [temp.expl.spec]/4 says this is valid.
7551 In this case, when we write:
7554 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7557 When we encounter #1, we want to store the partial instantiation
7558 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7560 For all cases other than this "explicit specialization of member of a
7561 class template", we just want to store the most general template into
7562 the CLASSTYPE_TI_TEMPLATE of M.
7564 This case of "explicit specialization of member of a class template"
7566 1/ the enclosing class is an instantiation of, and therefore not
7567 the same as, the context of the most general template, and
7568 2/ we aren't looking at the partial instantiation itself, i.e.
7569 the innermost arguments are not the same as the innermost parms of
7570 the most general template.
7572 So it's only when 1/ and 2/ happens that we want to use the partial
7573 instantiation of the member template in lieu of its most general
7576 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7577 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7578 /* the enclosing class must be an instantiation... */
7579 && CLASS_TYPE_P (context)
7580 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7582 tree partial_inst_args;
7583 TREE_VEC_LENGTH (arglist)--;
7584 ++processing_template_decl;
7586 tsubst (INNERMOST_TEMPLATE_ARGS
7587 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7588 arglist, complain, NULL_TREE);
7589 --processing_template_decl;
7590 TREE_VEC_LENGTH (arglist)++;
7591 use_partial_inst_tmpl =
7592 /*...and we must not be looking at the partial instantiation
7594 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7598 if (!use_partial_inst_tmpl)
7599 /* This case is easy; there are no member templates involved. */
7603 /* This is a full instantiation of a member template. Find
7604 the partial instantiation of which this is an instance. */
7606 /* Temporarily reduce by one the number of levels in the ARGLIST
7607 so as to avoid comparing the last set of arguments. */
7608 TREE_VEC_LENGTH (arglist)--;
7609 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7610 TREE_VEC_LENGTH (arglist)++;
7611 /* FOUND is either a proper class type, or an alias
7612 template specialization. In the later case, it's a
7613 TYPE_DECL, resulting from the substituting of arguments
7614 for parameters in the TYPE_DECL of the alias template
7615 done earlier. So be careful while getting the template
7617 found = TREE_CODE (found) == TYPE_DECL
7618 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7619 : CLASSTYPE_TI_TEMPLATE (found);
7622 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7625 slot = htab_find_slot_with_hash (type_specializations,
7626 &elt, hash, INSERT);
7627 entry = ggc_alloc_spec_entry ();
7631 /* Note this use of the partial instantiation so we can check it
7632 later in maybe_process_partial_specialization. */
7633 DECL_TEMPLATE_INSTANTIATIONS (templ)
7634 = tree_cons (arglist, t,
7635 DECL_TEMPLATE_INSTANTIATIONS (templ));
7637 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7638 /* Now that the type has been registered on the instantiations
7639 list, we set up the enumerators. Because the enumeration
7640 constants may involve the enumeration type itself, we make
7641 sure to register the type first, and then create the
7642 constants. That way, doing tsubst_expr for the enumeration
7643 constants won't result in recursive calls here; we'll find
7644 the instantiation and exit above. */
7645 tsubst_enum (template_type, t, arglist);
7647 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7648 /* If the type makes use of template parameters, the
7649 code that generates debugging information will crash. */
7650 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7652 /* Possibly limit visibility based on template args. */
7653 TREE_PUBLIC (type_decl) = 1;
7654 determine_visibility (type_decl);
7660 /* Wrapper for lookup_template_class_1. */
7663 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7664 int entering_scope, tsubst_flags_t complain)
7667 timevar_push (TV_TEMPLATE_INST);
7668 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7669 entering_scope, complain);
7670 timevar_pop (TV_TEMPLATE_INST);
7678 /* True when we should also visit template parameters that occur in
7679 non-deduced contexts. */
7680 bool include_nondeduced_p;
7681 struct pointer_set_t *visited;
7684 /* Called from for_each_template_parm via walk_tree. */
7687 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7690 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7691 tree_fn_t fn = pfd->fn;
7692 void *data = pfd->data;
7695 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7696 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7697 pfd->include_nondeduced_p))
7698 return error_mark_node;
7700 switch (TREE_CODE (t))
7703 if (TYPE_PTRMEMFUNC_P (t))
7709 if (!TYPE_TEMPLATE_INFO (t))
7711 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7712 fn, data, pfd->visited,
7713 pfd->include_nondeduced_p))
7714 return error_mark_node;
7718 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7719 fn, data, pfd->visited,
7720 pfd->include_nondeduced_p)
7721 || for_each_template_parm (TYPE_MAX_VALUE (t),
7722 fn, data, pfd->visited,
7723 pfd->include_nondeduced_p))
7724 return error_mark_node;
7728 /* Since we're not going to walk subtrees, we have to do this
7730 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7731 pfd->visited, pfd->include_nondeduced_p))
7732 return error_mark_node;
7736 /* Check the return type. */
7737 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7738 pfd->include_nondeduced_p))
7739 return error_mark_node;
7741 /* Check the parameter types. Since default arguments are not
7742 instantiated until they are needed, the TYPE_ARG_TYPES may
7743 contain expressions that involve template parameters. But,
7744 no-one should be looking at them yet. And, once they're
7745 instantiated, they don't contain template parameters, so
7746 there's no point in looking at them then, either. */
7750 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7751 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7752 pfd->visited, pfd->include_nondeduced_p))
7753 return error_mark_node;
7755 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7756 want walk_tree walking into them itself. */
7762 case UNDERLYING_TYPE:
7763 if (pfd->include_nondeduced_p
7764 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7766 pfd->include_nondeduced_p))
7767 return error_mark_node;
7772 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7773 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7774 pfd->visited, pfd->include_nondeduced_p))
7775 return error_mark_node;
7780 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7781 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7782 pfd->visited, pfd->include_nondeduced_p))
7783 return error_mark_node;
7784 if (DECL_CONTEXT (t)
7785 && pfd->include_nondeduced_p
7786 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7787 pfd->visited, pfd->include_nondeduced_p))
7788 return error_mark_node;
7791 case BOUND_TEMPLATE_TEMPLATE_PARM:
7792 /* Record template parameters such as `T' inside `TT<T>'. */
7793 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7794 pfd->include_nondeduced_p))
7795 return error_mark_node;
7798 case TEMPLATE_TEMPLATE_PARM:
7799 case TEMPLATE_TYPE_PARM:
7800 case TEMPLATE_PARM_INDEX:
7801 if (fn && (*fn)(t, data))
7802 return error_mark_node;
7804 return error_mark_node;
7808 /* A template template parameter is encountered. */
7809 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7810 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7811 pfd->include_nondeduced_p))
7812 return error_mark_node;
7814 /* Already substituted template template parameter */
7820 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7822 pfd->include_nondeduced_p))
7823 return error_mark_node;
7827 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7828 && pfd->include_nondeduced_p
7829 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7830 (TREE_TYPE (t)), fn, data,
7831 pfd->visited, pfd->include_nondeduced_p))
7832 return error_mark_node;
7837 /* If there's no type, then this thing must be some expression
7838 involving template parameters. */
7839 if (!fn && !TREE_TYPE (t))
7840 return error_mark_node;
7845 case IMPLICIT_CONV_EXPR:
7846 case REINTERPRET_CAST_EXPR:
7847 case CONST_CAST_EXPR:
7848 case STATIC_CAST_EXPR:
7849 case DYNAMIC_CAST_EXPR:
7853 case PSEUDO_DTOR_EXPR:
7855 return error_mark_node;
7862 /* We didn't find any template parameters we liked. */
7866 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7867 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7868 call FN with the parameter and the DATA.
7869 If FN returns nonzero, the iteration is terminated, and
7870 for_each_template_parm returns 1. Otherwise, the iteration
7871 continues. If FN never returns a nonzero value, the value
7872 returned by for_each_template_parm is 0. If FN is NULL, it is
7873 considered to be the function which always returns 1.
7875 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7876 parameters that occur in non-deduced contexts. When false, only
7877 visits those template parameters that can be deduced. */
7880 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7881 struct pointer_set_t *visited,
7882 bool include_nondeduced_p)
7884 struct pair_fn_data pfd;
7890 pfd.include_nondeduced_p = include_nondeduced_p;
7892 /* Walk the tree. (Conceptually, we would like to walk without
7893 duplicates, but for_each_template_parm_r recursively calls
7894 for_each_template_parm, so we would need to reorganize a fair
7895 bit to use walk_tree_without_duplicates, so we keep our own
7898 pfd.visited = visited;
7900 pfd.visited = pointer_set_create ();
7901 result = cp_walk_tree (&t,
7902 for_each_template_parm_r,
7904 pfd.visited) != NULL_TREE;
7909 pointer_set_destroy (pfd.visited);
7916 /* Returns true if T depends on any template parameter. */
7919 uses_template_parms (tree t)
7922 int saved_processing_template_decl;
7924 saved_processing_template_decl = processing_template_decl;
7925 if (!saved_processing_template_decl)
7926 processing_template_decl = 1;
7928 dependent_p = dependent_type_p (t);
7929 else if (TREE_CODE (t) == TREE_VEC)
7930 dependent_p = any_dependent_template_arguments_p (t);
7931 else if (TREE_CODE (t) == TREE_LIST)
7932 dependent_p = (uses_template_parms (TREE_VALUE (t))
7933 || uses_template_parms (TREE_CHAIN (t)));
7934 else if (TREE_CODE (t) == TYPE_DECL)
7935 dependent_p = dependent_type_p (TREE_TYPE (t));
7938 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7939 || TREE_CODE (t) == OVERLOAD
7941 || TREE_CODE (t) == IDENTIFIER_NODE
7942 || TREE_CODE (t) == TRAIT_EXPR
7943 || TREE_CODE (t) == CONSTRUCTOR
7944 || CONSTANT_CLASS_P (t))
7945 dependent_p = (type_dependent_expression_p (t)
7946 || value_dependent_expression_p (t));
7949 gcc_assert (t == error_mark_node);
7950 dependent_p = false;
7953 processing_template_decl = saved_processing_template_decl;
7958 /* Returns true if T depends on any template parameter with level LEVEL. */
7961 uses_template_parms_level (tree t, int level)
7963 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7964 /*include_nondeduced_p=*/true);
7967 /* Returns TRUE iff INST is an instantiation we don't need to do in an
7968 ill-formed translation unit, i.e. a variable or function that isn't
7969 usable in a constant expression. */
7972 neglectable_inst_p (tree d)
7975 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
7976 : decl_maybe_constant_var_p (d)));
7979 /* Returns TRUE iff we should refuse to instantiate DECL because it's
7980 neglectable and instantiated from within an erroneous instantiation. */
7983 limit_bad_template_recursion (tree decl)
7985 struct tinst_level *lev = current_tinst_level;
7986 int errs = errorcount + sorrycount;
7987 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
7990 for (; lev; lev = lev->next)
7991 if (neglectable_inst_p (lev->decl))
7994 return (lev && errs > lev->errors);
7997 static int tinst_depth;
7998 extern int max_tinst_depth;
7999 #ifdef GATHER_STATISTICS
8002 static GTY(()) struct tinst_level *last_error_tinst_level;
8004 /* We're starting to instantiate D; record the template instantiation context
8005 for diagnostics and to restore it later. */
8008 push_tinst_level (tree d)
8010 struct tinst_level *new_level;
8012 if (tinst_depth >= max_tinst_depth)
8014 last_error_tinst_level = current_tinst_level;
8015 if (TREE_CODE (d) == TREE_LIST)
8016 error ("template instantiation depth exceeds maximum of %d (use "
8017 "-ftemplate-depth= to increase the maximum) substituting %qS",
8018 max_tinst_depth, d);
8020 error ("template instantiation depth exceeds maximum of %d (use "
8021 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8022 max_tinst_depth, d);
8024 print_instantiation_context ();
8029 /* If the current instantiation caused problems, don't let it instantiate
8030 anything else. Do allow deduction substitution and decls usable in
8031 constant expressions. */
8032 if (limit_bad_template_recursion (d))
8035 new_level = ggc_alloc_tinst_level ();
8036 new_level->decl = d;
8037 new_level->locus = input_location;
8038 new_level->errors = errorcount+sorrycount;
8039 new_level->in_system_header_p = in_system_header;
8040 new_level->next = current_tinst_level;
8041 current_tinst_level = new_level;
8044 #ifdef GATHER_STATISTICS
8045 if (tinst_depth > depth_reached)
8046 depth_reached = tinst_depth;
8052 /* We're done instantiating this template; return to the instantiation
8056 pop_tinst_level (void)
8058 /* Restore the filename and line number stashed away when we started
8059 this instantiation. */
8060 input_location = current_tinst_level->locus;
8061 current_tinst_level = current_tinst_level->next;
8065 /* We're instantiating a deferred template; restore the template
8066 instantiation context in which the instantiation was requested, which
8067 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8070 reopen_tinst_level (struct tinst_level *level)
8072 struct tinst_level *t;
8075 for (t = level; t; t = t->next)
8078 current_tinst_level = level;
8080 if (current_tinst_level)
8081 current_tinst_level->errors = errorcount+sorrycount;
8085 /* Returns the TINST_LEVEL which gives the original instantiation
8088 struct tinst_level *
8089 outermost_tinst_level (void)
8091 struct tinst_level *level = current_tinst_level;
8094 level = level->next;
8098 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8101 parameter_of_template_p (tree parm, tree templ)
8106 if (!parm || !templ)
8109 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8110 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8112 parms = DECL_TEMPLATE_PARMS (templ);
8113 parms = INNERMOST_TEMPLATE_PARMS (parms);
8115 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8117 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8119 || (DECL_INITIAL (parm)
8120 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8127 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8128 vector of template arguments, as for tsubst.
8130 Returns an appropriate tsubst'd friend declaration. */
8133 tsubst_friend_function (tree decl, tree args)
8137 if (TREE_CODE (decl) == FUNCTION_DECL
8138 && DECL_TEMPLATE_INSTANTIATION (decl)
8139 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8140 /* This was a friend declared with an explicit template
8141 argument list, e.g.:
8145 to indicate that f was a template instantiation, not a new
8146 function declaration. Now, we have to figure out what
8147 instantiation of what template. */
8149 tree template_id, arglist, fns;
8152 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8154 /* Friend functions are looked up in the containing namespace scope.
8155 We must enter that scope, to avoid finding member functions of the
8156 current class with same name. */
8157 push_nested_namespace (ns);
8158 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8159 tf_warning_or_error, NULL_TREE,
8160 /*integral_constant_expression_p=*/false);
8161 pop_nested_namespace (ns);
8162 arglist = tsubst (DECL_TI_ARGS (decl), args,
8163 tf_warning_or_error, NULL_TREE);
8164 template_id = lookup_template_function (fns, arglist);
8166 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8167 tmpl = determine_specialization (template_id, new_friend,
8169 /*need_member_template=*/0,
8170 TREE_VEC_LENGTH (args),
8172 return instantiate_template (tmpl, new_args, tf_error);
8175 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8177 /* The NEW_FRIEND will look like an instantiation, to the
8178 compiler, but is not an instantiation from the point of view of
8179 the language. For example, we might have had:
8181 template <class T> struct S {
8182 template <class U> friend void f(T, U);
8185 Then, in S<int>, template <class U> void f(int, U) is not an
8186 instantiation of anything. */
8187 if (new_friend == error_mark_node)
8188 return error_mark_node;
8190 DECL_USE_TEMPLATE (new_friend) = 0;
8191 if (TREE_CODE (decl) == TEMPLATE_DECL)
8193 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8194 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8195 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8198 /* The mangled name for the NEW_FRIEND is incorrect. The function
8199 is not a template instantiation and should not be mangled like
8200 one. Therefore, we forget the mangling here; we'll recompute it
8201 later if we need it. */
8202 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8204 SET_DECL_RTL (new_friend, NULL);
8205 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8208 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8211 tree new_friend_template_info;
8212 tree new_friend_result_template_info;
8214 int new_friend_is_defn;
8216 /* We must save some information from NEW_FRIEND before calling
8217 duplicate decls since that function will free NEW_FRIEND if
8219 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8220 new_friend_is_defn =
8221 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8222 (template_for_substitution (new_friend)))
8224 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8226 /* This declaration is a `primary' template. */
8227 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8229 new_friend_result_template_info
8230 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8233 new_friend_result_template_info = NULL_TREE;
8235 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8236 if (new_friend_is_defn)
8237 DECL_INITIAL (new_friend) = error_mark_node;
8239 /* Inside pushdecl_namespace_level, we will push into the
8240 current namespace. However, the friend function should go
8241 into the namespace of the template. */
8242 ns = decl_namespace_context (new_friend);
8243 push_nested_namespace (ns);
8244 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8245 pop_nested_namespace (ns);
8247 if (old_decl == error_mark_node)
8248 return error_mark_node;
8250 if (old_decl != new_friend)
8252 /* This new friend declaration matched an existing
8253 declaration. For example, given:
8255 template <class T> void f(T);
8256 template <class U> class C {
8257 template <class T> friend void f(T) {}
8260 the friend declaration actually provides the definition
8261 of `f', once C has been instantiated for some type. So,
8262 old_decl will be the out-of-class template declaration,
8263 while new_friend is the in-class definition.
8265 But, if `f' was called before this point, the
8266 instantiation of `f' will have DECL_TI_ARGS corresponding
8267 to `T' but not to `U', references to which might appear
8268 in the definition of `f'. Previously, the most general
8269 template for an instantiation of `f' was the out-of-class
8270 version; now it is the in-class version. Therefore, we
8271 run through all specialization of `f', adding to their
8272 DECL_TI_ARGS appropriately. In particular, they need a
8273 new set of outer arguments, corresponding to the
8274 arguments for this class instantiation.
8276 The same situation can arise with something like this:
8279 template <class T> class C {
8283 when `C<int>' is instantiated. Now, `f(int)' is defined
8286 if (!new_friend_is_defn)
8287 /* On the other hand, if the in-class declaration does
8288 *not* provide a definition, then we don't want to alter
8289 existing definitions. We can just leave everything
8294 tree new_template = TI_TEMPLATE (new_friend_template_info);
8295 tree new_args = TI_ARGS (new_friend_template_info);
8297 /* Overwrite whatever template info was there before, if
8298 any, with the new template information pertaining to
8300 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8302 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8304 /* We should have called reregister_specialization in
8306 gcc_assert (retrieve_specialization (new_template,
8310 /* Instantiate it if the global has already been used. */
8311 if (DECL_ODR_USED (old_decl))
8312 instantiate_decl (old_decl, /*defer_ok=*/true,
8313 /*expl_inst_class_mem_p=*/false);
8319 /* Indicate that the old function template is a partial
8321 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8322 = new_friend_result_template_info;
8324 gcc_assert (new_template
8325 == most_general_template (new_template));
8326 gcc_assert (new_template != old_decl);
8328 /* Reassign any specializations already in the hash table
8329 to the new more general template, and add the
8330 additional template args. */
8331 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8335 tree spec = TREE_VALUE (t);
8338 elt.tmpl = old_decl;
8339 elt.args = DECL_TI_ARGS (spec);
8340 elt.spec = NULL_TREE;
8342 htab_remove_elt (decl_specializations, &elt);
8345 = add_outermost_template_args (new_args,
8346 DECL_TI_ARGS (spec));
8348 register_specialization
8349 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8352 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8356 /* The information from NEW_FRIEND has been merged into OLD_DECL
8357 by duplicate_decls. */
8358 new_friend = old_decl;
8363 tree context = DECL_CONTEXT (new_friend);
8367 template <class T> class C {
8368 template <class U> friend void C1<U>::f (); // case 1
8369 friend void C2<T>::f (); // case 2
8371 we only need to make sure CONTEXT is a complete type for
8372 case 2. To distinguish between the two cases, we note that
8373 CONTEXT of case 1 remains dependent type after tsubst while
8374 this isn't true for case 2. */
8375 ++processing_template_decl;
8376 dependent_p = dependent_type_p (context);
8377 --processing_template_decl;
8380 && !complete_type_or_else (context, NULL_TREE))
8381 return error_mark_node;
8383 if (COMPLETE_TYPE_P (context))
8385 /* Check to see that the declaration is really present, and,
8386 possibly obtain an improved declaration. */
8387 tree fn = check_classfn (context,
8388 new_friend, NULL_TREE);
8398 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8399 template arguments, as for tsubst.
8401 Returns an appropriate tsubst'd friend type or error_mark_node on
8405 tsubst_friend_class (tree friend_tmpl, tree args)
8411 context = CP_DECL_CONTEXT (friend_tmpl);
8413 if (context != global_namespace)
8415 if (TREE_CODE (context) == NAMESPACE_DECL)
8416 push_nested_namespace (context);
8418 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8421 /* Look for a class template declaration. We look for hidden names
8422 because two friend declarations of the same template are the
8423 same. For example, in:
8426 template <typename> friend class F;
8428 template <typename> struct B {
8429 template <typename> friend class F;
8432 both F templates are the same. */
8433 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8434 /*block_p=*/true, 0,
8435 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8437 /* But, if we don't find one, it might be because we're in a
8438 situation like this:
8446 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8447 for `S<int>', not the TEMPLATE_DECL. */
8448 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8450 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8451 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8454 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8456 /* The friend template has already been declared. Just
8457 check to see that the declarations match, and install any new
8458 default parameters. We must tsubst the default parameters,
8459 of course. We only need the innermost template parameters
8460 because that is all that redeclare_class_template will look
8462 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8463 > TMPL_ARGS_DEPTH (args))
8466 location_t saved_input_location;
8467 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8468 args, tf_warning_or_error);
8470 saved_input_location = input_location;
8471 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8472 redeclare_class_template (TREE_TYPE (tmpl), parms);
8473 input_location = saved_input_location;
8477 friend_type = TREE_TYPE (tmpl);
8481 /* The friend template has not already been declared. In this
8482 case, the instantiation of the template class will cause the
8483 injection of this template into the global scope. */
8484 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8485 if (tmpl == error_mark_node)
8486 return error_mark_node;
8488 /* The new TMPL is not an instantiation of anything, so we
8489 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8490 the new type because that is supposed to be the corresponding
8491 template decl, i.e., TMPL. */
8492 DECL_USE_TEMPLATE (tmpl) = 0;
8493 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8494 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8495 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8496 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8498 /* Inject this template into the global scope. */
8499 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8502 if (context != global_namespace)
8504 if (TREE_CODE (context) == NAMESPACE_DECL)
8505 pop_nested_namespace (context);
8507 pop_nested_class ();
8513 /* Returns zero if TYPE cannot be completed later due to circularity.
8514 Otherwise returns one. */
8517 can_complete_type_without_circularity (tree type)
8519 if (type == NULL_TREE || type == error_mark_node)
8521 else if (COMPLETE_TYPE_P (type))
8523 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8524 return can_complete_type_without_circularity (TREE_TYPE (type));
8525 else if (CLASS_TYPE_P (type)
8526 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8532 /* Apply any attributes which had to be deferred until instantiation
8533 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8534 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8537 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8538 tree args, tsubst_flags_t complain, tree in_decl)
8540 tree last_dep = NULL_TREE;
8544 for (t = attributes; t; t = TREE_CHAIN (t))
8545 if (ATTR_IS_DEPENDENT (t))
8548 attributes = copy_list (attributes);
8552 if (DECL_P (*decl_p))
8554 if (TREE_TYPE (*decl_p) == error_mark_node)
8556 p = &DECL_ATTRIBUTES (*decl_p);
8559 p = &TYPE_ATTRIBUTES (*decl_p);
8563 tree late_attrs = NULL_TREE;
8564 tree *q = &late_attrs;
8566 for (*p = attributes; *p; )
8569 if (ATTR_IS_DEPENDENT (t))
8571 *p = TREE_CHAIN (t);
8572 TREE_CHAIN (t) = NULL_TREE;
8573 /* If the first attribute argument is an identifier, don't
8574 pass it through tsubst. Attributes like mode, format,
8575 cleanup and several target specific attributes expect it
8578 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8579 && TREE_VALUE (TREE_VALUE (t))
8580 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8581 == IDENTIFIER_NODE))
8584 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8586 /*integral_constant_expression_p=*/false);
8587 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8589 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8594 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8595 /*integral_constant_expression_p=*/false);
8597 q = &TREE_CHAIN (t);
8600 p = &TREE_CHAIN (t);
8603 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8607 /* Perform (or defer) access check for typedefs that were referenced
8608 from within the template TMPL code.
8609 This is a subroutine of instantiate_template and instantiate_class_template.
8610 TMPL is the template to consider and TARGS is the list of arguments of
8614 perform_typedefs_access_check (tree tmpl, tree targs)
8616 location_t saved_location;
8618 qualified_typedef_usage_t *iter;
8621 || (!CLASS_TYPE_P (tmpl)
8622 && TREE_CODE (tmpl) != FUNCTION_DECL))
8625 saved_location = input_location;
8626 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8627 get_types_needing_access_check (tmpl),
8630 tree type_decl = iter->typedef_decl;
8631 tree type_scope = iter->context;
8633 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8636 if (uses_template_parms (type_decl))
8637 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8638 if (uses_template_parms (type_scope))
8639 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8641 /* Make access check error messages point to the location
8642 of the use of the typedef. */
8643 input_location = iter->locus;
8644 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8645 type_decl, type_decl);
8647 input_location = saved_location;
8651 instantiate_class_template_1 (tree type)
8653 tree templ, args, pattern, t, member;
8657 unsigned int saved_maximum_field_alignment;
8659 if (type == error_mark_node)
8660 return error_mark_node;
8662 if (COMPLETE_OR_OPEN_TYPE_P (type)
8663 || uses_template_parms (type))
8666 /* Figure out which template is being instantiated. */
8667 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8668 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8670 /* Determine what specialization of the original template to
8672 t = most_specialized_class (type, templ, tf_warning_or_error);
8673 if (t == error_mark_node)
8675 TYPE_BEING_DEFINED (type) = 1;
8676 return error_mark_node;
8680 /* This TYPE is actually an instantiation of a partial
8681 specialization. We replace the innermost set of ARGS with
8682 the arguments appropriate for substitution. For example,
8685 template <class T> struct S {};
8686 template <class T> struct S<T*> {};
8688 and supposing that we are instantiating S<int*>, ARGS will
8689 presently be {int*} -- but we need {int}. */
8690 pattern = TREE_TYPE (t);
8691 args = TREE_PURPOSE (t);
8695 pattern = TREE_TYPE (templ);
8696 args = CLASSTYPE_TI_ARGS (type);
8699 /* If the template we're instantiating is incomplete, then clearly
8700 there's nothing we can do. */
8701 if (!COMPLETE_TYPE_P (pattern))
8704 /* If we've recursively instantiated too many templates, stop. */
8705 if (! push_tinst_level (type))
8708 /* Now we're really doing the instantiation. Mark the type as in
8709 the process of being defined. */
8710 TYPE_BEING_DEFINED (type) = 1;
8712 /* We may be in the middle of deferred access check. Disable
8714 push_deferring_access_checks (dk_no_deferred);
8716 push_to_top_level ();
8717 /* Use #pragma pack from the template context. */
8718 saved_maximum_field_alignment = maximum_field_alignment;
8719 maximum_field_alignment = TYPE_PRECISION (pattern);
8721 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8723 /* Set the input location to the most specialized template definition.
8724 This is needed if tsubsting causes an error. */
8725 typedecl = TYPE_MAIN_DECL (pattern);
8726 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8727 DECL_SOURCE_LOCATION (typedecl);
8729 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8730 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8731 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8732 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8733 if (ANON_AGGR_TYPE_P (pattern))
8734 SET_ANON_AGGR_TYPE_P (type);
8735 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8737 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8738 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8739 /* Adjust visibility for template arguments. */
8740 determine_visibility (TYPE_MAIN_DECL (type));
8742 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8744 pbinfo = TYPE_BINFO (pattern);
8746 /* We should never instantiate a nested class before its enclosing
8747 class; we need to look up the nested class by name before we can
8748 instantiate it, and that lookup should instantiate the enclosing
8750 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8751 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8753 base_list = NULL_TREE;
8754 if (BINFO_N_BASE_BINFOS (pbinfo))
8760 /* We must enter the scope containing the type, as that is where
8761 the accessibility of types named in dependent bases are
8763 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8765 /* Substitute into each of the bases to determine the actual
8767 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8770 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8771 tree expanded_bases = NULL_TREE;
8774 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8777 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8778 args, tf_error, NULL_TREE);
8779 if (expanded_bases == error_mark_node)
8782 len = TREE_VEC_LENGTH (expanded_bases);
8785 for (idx = 0; idx < len; idx++)
8788 /* Extract the already-expanded base class. */
8789 base = TREE_VEC_ELT (expanded_bases, idx);
8791 /* Substitute to figure out the base class. */
8792 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8795 if (base == error_mark_node)
8798 base_list = tree_cons (access, base, base_list);
8799 if (BINFO_VIRTUAL_P (pbase_binfo))
8800 TREE_TYPE (base_list) = integer_type_node;
8804 /* The list is now in reverse order; correct that. */
8805 base_list = nreverse (base_list);
8808 pop_scope (pushed_scope);
8810 /* Now call xref_basetypes to set up all the base-class
8812 xref_basetypes (type, base_list);
8814 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8815 (int) ATTR_FLAG_TYPE_IN_PLACE,
8816 args, tf_error, NULL_TREE);
8817 fixup_attribute_variants (type);
8819 /* Now that our base classes are set up, enter the scope of the
8820 class, so that name lookups into base classes, etc. will work
8821 correctly. This is precisely analogous to what we do in
8822 begin_class_definition when defining an ordinary non-template
8823 class, except we also need to push the enclosing classes. */
8824 push_nested_class (type);
8826 /* Now members are processed in the order of declaration. */
8827 for (member = CLASSTYPE_DECL_LIST (pattern);
8828 member; member = TREE_CHAIN (member))
8830 tree t = TREE_VALUE (member);
8832 if (TREE_PURPOSE (member))
8836 /* Build new CLASSTYPE_NESTED_UTDS. */
8839 bool class_template_p;
8841 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8842 && TYPE_LANG_SPECIFIC (t)
8843 && CLASSTYPE_IS_TEMPLATE (t));
8844 /* If the member is a class template, then -- even after
8845 substitution -- there may be dependent types in the
8846 template argument list for the class. We increment
8847 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8848 that function will assume that no types are dependent
8849 when outside of a template. */
8850 if (class_template_p)
8851 ++processing_template_decl;
8852 newtag = tsubst (t, args, tf_error, NULL_TREE);
8853 if (class_template_p)
8854 --processing_template_decl;
8855 if (newtag == error_mark_node)
8858 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8860 tree name = TYPE_IDENTIFIER (t);
8862 if (class_template_p)
8863 /* Unfortunately, lookup_template_class sets
8864 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8865 instantiation (i.e., for the type of a member
8866 template class nested within a template class.)
8867 This behavior is required for
8868 maybe_process_partial_specialization to work
8869 correctly, but is not accurate in this case;
8870 the TAG is not an instantiation of anything.
8871 (The corresponding TEMPLATE_DECL is an
8872 instantiation, but the TYPE is not.) */
8873 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8875 /* Now, we call pushtag to put this NEWTAG into the scope of
8876 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8877 pushtag calling push_template_decl. We don't have to do
8878 this for enums because it will already have been done in
8881 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8882 pushtag (name, newtag, /*tag_scope=*/ts_current);
8885 else if (TREE_CODE (t) == FUNCTION_DECL
8886 || DECL_FUNCTION_TEMPLATE_P (t))
8888 /* Build new TYPE_METHODS. */
8891 if (TREE_CODE (t) == TEMPLATE_DECL)
8892 ++processing_template_decl;
8893 r = tsubst (t, args, tf_error, NULL_TREE);
8894 if (TREE_CODE (t) == TEMPLATE_DECL)
8895 --processing_template_decl;
8896 set_current_access_from_decl (r);
8897 finish_member_declaration (r);
8898 /* Instantiate members marked with attribute used. */
8899 if (r != error_mark_node && DECL_PRESERVE_P (r))
8904 /* Build new TYPE_FIELDS. */
8905 if (TREE_CODE (t) == STATIC_ASSERT)
8908 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8909 tf_warning_or_error, NULL_TREE,
8910 /*integral_constant_expression_p=*/true);
8911 finish_static_assert (condition,
8912 STATIC_ASSERT_MESSAGE (t),
8913 STATIC_ASSERT_SOURCE_LOCATION (t),
8916 else if (TREE_CODE (t) != CONST_DECL)
8920 /* The file and line for this declaration, to
8921 assist in error message reporting. Since we
8922 called push_tinst_level above, we don't need to
8924 input_location = DECL_SOURCE_LOCATION (t);
8926 if (TREE_CODE (t) == TEMPLATE_DECL)
8927 ++processing_template_decl;
8928 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8929 if (TREE_CODE (t) == TEMPLATE_DECL)
8930 --processing_template_decl;
8931 if (TREE_CODE (r) == VAR_DECL)
8935 [t]he initialization (and any associated
8936 side-effects) of a static data member does
8937 not occur unless the static data member is
8938 itself used in a way that requires the
8939 definition of the static data member to
8942 Therefore, we do not substitute into the
8943 initialized for the static data member here. */
8944 finish_static_data_member_decl
8947 /*init_const_expr_p=*/false,
8948 /*asmspec_tree=*/NULL_TREE,
8950 /* Instantiate members marked with attribute used. */
8951 if (r != error_mark_node && DECL_PRESERVE_P (r))
8954 else if (TREE_CODE (r) == FIELD_DECL)
8956 /* Determine whether R has a valid type and can be
8957 completed later. If R is invalid, then it is
8958 replaced by error_mark_node so that it will not be
8959 added to TYPE_FIELDS. */
8960 tree rtype = TREE_TYPE (r);
8961 if (can_complete_type_without_circularity (rtype))
8962 complete_type (rtype);
8964 if (!COMPLETE_TYPE_P (rtype))
8966 cxx_incomplete_type_error (r, rtype);
8967 r = error_mark_node;
8971 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8972 such a thing will already have been added to the field
8973 list by tsubst_enum in finish_member_declaration in the
8974 CLASSTYPE_NESTED_UTDS case above. */
8975 if (!(TREE_CODE (r) == TYPE_DECL
8976 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8977 && DECL_ARTIFICIAL (r)))
8979 set_current_access_from_decl (r);
8980 finish_member_declaration (r);
8987 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8989 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8991 tree friend_type = t;
8992 bool adjust_processing_template_decl = false;
8994 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8996 /* template <class T> friend class C; */
8997 friend_type = tsubst_friend_class (friend_type, args);
8998 adjust_processing_template_decl = true;
9000 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9002 /* template <class T> friend class C::D; */
9003 friend_type = tsubst (friend_type, args,
9004 tf_warning_or_error, NULL_TREE);
9005 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9006 friend_type = TREE_TYPE (friend_type);
9007 adjust_processing_template_decl = true;
9009 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9010 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9012 /* This could be either
9016 when dependent_type_p is false or
9018 template <class U> friend class T::C;
9021 friend_type = tsubst (friend_type, args,
9022 tf_warning_or_error, NULL_TREE);
9023 /* Bump processing_template_decl for correct
9024 dependent_type_p calculation. */
9025 ++processing_template_decl;
9026 if (dependent_type_p (friend_type))
9027 adjust_processing_template_decl = true;
9028 --processing_template_decl;
9030 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9031 && hidden_name_p (TYPE_NAME (friend_type)))
9035 where C hasn't been declared yet. Let's lookup name
9036 from namespace scope directly, bypassing any name that
9037 come from dependent base class. */
9038 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9040 /* The call to xref_tag_from_type does injection for friend
9042 push_nested_namespace (ns);
9044 xref_tag_from_type (friend_type, NULL_TREE,
9045 /*tag_scope=*/ts_current);
9046 pop_nested_namespace (ns);
9048 else if (uses_template_parms (friend_type))
9049 /* friend class C<T>; */
9050 friend_type = tsubst (friend_type, args,
9051 tf_warning_or_error, NULL_TREE);
9056 where C is already declared or
9058 friend class C<int>;
9060 We don't have to do anything in these cases. */
9062 if (adjust_processing_template_decl)
9063 /* Trick make_friend_class into realizing that the friend
9064 we're adding is a template, not an ordinary class. It's
9065 important that we use make_friend_class since it will
9066 perform some error-checking and output cross-reference
9068 ++processing_template_decl;
9070 if (friend_type != error_mark_node)
9071 make_friend_class (type, friend_type, /*complain=*/false);
9073 if (adjust_processing_template_decl)
9074 --processing_template_decl;
9078 /* Build new DECL_FRIENDLIST. */
9081 /* The file and line for this declaration, to
9082 assist in error message reporting. Since we
9083 called push_tinst_level above, we don't need to
9085 input_location = DECL_SOURCE_LOCATION (t);
9087 if (TREE_CODE (t) == TEMPLATE_DECL)
9089 ++processing_template_decl;
9090 push_deferring_access_checks (dk_no_check);
9093 r = tsubst_friend_function (t, args);
9094 add_friend (type, r, /*complain=*/false);
9095 if (TREE_CODE (t) == TEMPLATE_DECL)
9097 pop_deferring_access_checks ();
9098 --processing_template_decl;
9104 if (CLASSTYPE_LAMBDA_EXPR (type))
9106 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9107 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9109 apply_lambda_return_type (lambda, void_type_node);
9110 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9112 instantiate_decl (lambda_function (type), false, false);
9113 maybe_add_lambda_conv_op (type);
9116 /* Set the file and line number information to whatever is given for
9117 the class itself. This puts error messages involving generated
9118 implicit functions at a predictable point, and the same point
9119 that would be used for non-template classes. */
9120 input_location = DECL_SOURCE_LOCATION (typedecl);
9122 unreverse_member_declarations (type);
9123 finish_struct_1 (type);
9124 TYPE_BEING_DEFINED (type) = 0;
9126 /* We don't instantiate default arguments for member functions. 14.7.1:
9128 The implicit instantiation of a class template specialization causes
9129 the implicit instantiation of the declarations, but not of the
9130 definitions or default arguments, of the class member functions,
9131 member classes, static data members and member templates.... */
9133 /* Some typedefs referenced from within the template code need to be access
9134 checked at template instantiation time, i.e now. These types were
9135 added to the template at parsing time. Let's get those and perform
9136 the access checks then. */
9137 perform_typedefs_access_check (pattern, args);
9138 perform_deferred_access_checks ();
9139 pop_nested_class ();
9140 maximum_field_alignment = saved_maximum_field_alignment;
9141 pop_from_top_level ();
9142 pop_deferring_access_checks ();
9145 /* The vtable for a template class can be emitted in any translation
9146 unit in which the class is instantiated. When there is no key
9147 method, however, finish_struct_1 will already have added TYPE to
9148 the keyed_classes list. */
9149 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9150 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9155 /* Wrapper for instantiate_class_template_1. */
9158 instantiate_class_template (tree type)
9161 timevar_push (TV_TEMPLATE_INST);
9162 ret = instantiate_class_template_1 (type);
9163 timevar_pop (TV_TEMPLATE_INST);
9168 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9174 else if (TYPE_P (t))
9175 r = tsubst (t, args, complain, in_decl);
9178 if (!(complain & tf_warning))
9179 ++c_inhibit_evaluation_warnings;
9180 r = tsubst_expr (t, args, complain, in_decl,
9181 /*integral_constant_expression_p=*/true);
9182 if (!(complain & tf_warning))
9183 --c_inhibit_evaluation_warnings;
9184 /* Preserve the raw-reference nature of T. */
9185 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9186 && REFERENCE_REF_P (r))
9187 r = TREE_OPERAND (r, 0);
9192 /* Given a function parameter pack TMPL_PARM and some function parameters
9193 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9194 and set *SPEC_P to point at the next point in the list. */
9197 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9199 /* Collect all of the extra "packed" parameters into an
9203 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9204 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9205 tree spec_parm = *spec_p;
9208 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9210 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9213 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9214 parmvec = make_tree_vec (len);
9215 parmtypevec = make_tree_vec (len);
9216 spec_parm = *spec_p;
9217 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9219 TREE_VEC_ELT (parmvec, i) = spec_parm;
9220 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9223 /* Build the argument packs. */
9224 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9225 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9226 TREE_TYPE (argpack) = argtypepack;
9227 *spec_p = spec_parm;
9232 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9233 NONTYPE_ARGUMENT_PACK. */
9236 make_fnparm_pack (tree spec_parm)
9238 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9241 /* Substitute ARGS into T, which is an pack expansion
9242 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9243 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9244 (if only a partial substitution could be performed) or
9245 ERROR_MARK_NODE if there was an error. */
9247 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9251 tree pack, packs = NULL_TREE;
9252 bool unsubstituted_packs = false;
9253 bool real_packs = false;
9254 int missing_level = 0;
9257 htab_t saved_local_specializations = NULL;
9260 gcc_assert (PACK_EXPANSION_P (t));
9261 pattern = PACK_EXPANSION_PATTERN (t);
9263 /* Add in any args remembered from an earlier partial instantiation. */
9264 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9266 levels = TMPL_ARGS_DEPTH (args);
9268 /* Determine the argument packs that will instantiate the parameter
9269 packs used in the expansion expression. While we're at it,
9270 compute the number of arguments to be expanded and make sure it
9272 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9273 pack = TREE_CHAIN (pack))
9275 tree parm_pack = TREE_VALUE (pack);
9276 tree arg_pack = NULL_TREE;
9277 tree orig_arg = NULL_TREE;
9280 if (TREE_CODE (parm_pack) == BASES)
9282 if (BASES_DIRECT (parm_pack))
9283 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9284 args, complain, in_decl, false));
9286 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9287 args, complain, in_decl, false));
9289 if (TREE_CODE (parm_pack) == PARM_DECL)
9291 if (!cp_unevaluated_operand)
9292 arg_pack = retrieve_local_specialization (parm_pack);
9295 /* We can't rely on local_specializations for a parameter
9296 name used later in a function declaration (such as in a
9297 late-specified return type). Even if it exists, it might
9298 have the wrong value for a recursive call. Just make a
9299 dummy decl, since it's only used for its type. */
9300 arg_pack = tsubst_decl (parm_pack, args, complain);
9301 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9302 /* Partial instantiation of the parm_pack, we can't build
9303 up an argument pack yet. */
9304 arg_pack = NULL_TREE;
9306 arg_pack = make_fnparm_pack (arg_pack);
9312 template_parm_level_and_index (parm_pack, &level, &idx);
9314 if (level <= levels)
9315 arg_pack = TMPL_ARG (args, level, idx);
9318 orig_arg = arg_pack;
9319 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9320 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9322 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9323 /* This can only happen if we forget to expand an argument
9324 pack somewhere else. Just return an error, silently. */
9326 result = make_tree_vec (1);
9327 TREE_VEC_ELT (result, 0) = error_mark_node;
9331 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9332 /* The argument pack that the parameter maps to is just an
9333 expansion of the parameter itself, such as one would find
9334 in the implicit typedef of a class inside the class itself.
9335 Consider this parameter "unsubstituted", so that we will
9336 maintain the outer pack expansion. */
9337 arg_pack = NULL_TREE;
9342 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9344 /* Don't bother trying to do a partial substitution with
9345 incomplete packs; we'll try again after deduction. */
9346 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9351 else if (len != my_len)
9353 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9354 error ("mismatched argument pack lengths while expanding "
9358 error ("mismatched argument pack lengths while expanding "
9361 return error_mark_node;
9364 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9365 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9367 /* This isn't a real argument pack yet. */;
9371 /* Keep track of the parameter packs and their corresponding
9373 packs = tree_cons (parm_pack, arg_pack, packs);
9374 TREE_TYPE (packs) = orig_arg;
9378 /* We can't substitute for this parameter pack. We use a flag as
9379 well as the missing_level counter because function parameter
9380 packs don't have a level. */
9381 unsubstituted_packs = true;
9382 if (!missing_level || missing_level > level)
9383 missing_level = level;
9387 /* We cannot expand this expansion expression, because we don't have
9388 all of the argument packs we need. */
9389 if (unsubstituted_packs)
9393 /* We got some full packs, but we can't substitute them in until we
9394 have values for all the packs. So remember these until then. */
9397 t = make_pack_expansion (pattern);
9399 /* The call to add_to_template_args above assumes no overlap
9400 between saved args and new args, so prune away any fake
9401 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9402 if (missing_level && levels >= missing_level)
9404 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9405 && missing_level > 1);
9406 TREE_VEC_LENGTH (args) = missing_level - 1;
9407 save_args = copy_node (args);
9408 TREE_VEC_LENGTH (args) = levels;
9413 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9417 /* There were no real arguments, we're just replacing a parameter
9418 pack with another version of itself. Substitute into the
9419 pattern and return a PACK_EXPANSION_*. The caller will need to
9421 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9422 t = tsubst_expr (pattern, args, complain, in_decl,
9423 /*integral_constant_expression_p=*/false);
9425 t = tsubst (pattern, args, complain, in_decl);
9426 t = make_pack_expansion (t);
9431 /* We could not find any argument packs that work. */
9433 return error_mark_node;
9435 if (cp_unevaluated_operand)
9437 /* We're in a late-specified return type, so create our own local
9438 specializations table; the current table is either NULL or (in the
9439 case of recursive unification) might have bindings that we don't
9440 want to use or alter. */
9441 saved_local_specializations = local_specializations;
9442 local_specializations = htab_create (37,
9443 hash_local_specialization,
9444 eq_local_specializations,
9448 /* For each argument in each argument pack, substitute into the
9450 result = make_tree_vec (len);
9451 for (i = 0; i < len; ++i)
9453 /* For parameter pack, change the substitution of the parameter
9454 pack to the ith argument in its argument pack, then expand
9456 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9458 tree parm = TREE_PURPOSE (pack);
9461 /* Select the Ith argument from the pack. */
9462 if (TREE_CODE (parm) == PARM_DECL)
9466 arg = make_node (ARGUMENT_PACK_SELECT);
9467 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9469 register_local_specialization (arg, parm);
9472 arg = retrieve_local_specialization (parm);
9477 template_parm_level_and_index (parm, &level, &idx);
9481 arg = make_node (ARGUMENT_PACK_SELECT);
9482 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9483 /* Update the corresponding argument. */
9484 TMPL_ARG (args, level, idx) = arg;
9487 /* Re-use the ARGUMENT_PACK_SELECT. */
9488 arg = TMPL_ARG (args, level, idx);
9490 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9493 /* Substitute into the PATTERN with the altered arguments. */
9494 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9495 TREE_VEC_ELT (result, i) =
9496 tsubst_expr (pattern, args, complain, in_decl,
9497 /*integral_constant_expression_p=*/false);
9499 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9501 if (TREE_VEC_ELT (result, i) == error_mark_node)
9503 result = error_mark_node;
9508 /* Update ARGS to restore the substitution from parameter packs to
9509 their argument packs. */
9510 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9512 tree parm = TREE_PURPOSE (pack);
9514 if (TREE_CODE (parm) == PARM_DECL)
9515 register_local_specialization (TREE_TYPE (pack), parm);
9519 template_parm_level_and_index (parm, &level, &idx);
9521 /* Update the corresponding argument. */
9522 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9523 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9526 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9530 if (saved_local_specializations)
9532 htab_delete (local_specializations);
9533 local_specializations = saved_local_specializations;
9539 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9540 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9541 parameter packs; all parms generated from a function parameter pack will
9542 have the same DECL_PARM_INDEX. */
9545 get_pattern_parm (tree parm, tree tmpl)
9547 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9550 if (DECL_ARTIFICIAL (parm))
9552 for (patparm = DECL_ARGUMENTS (pattern);
9553 patparm; patparm = DECL_CHAIN (patparm))
9554 if (DECL_ARTIFICIAL (patparm)
9555 && DECL_NAME (parm) == DECL_NAME (patparm))
9560 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9561 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9562 gcc_assert (DECL_PARM_INDEX (patparm)
9563 == DECL_PARM_INDEX (parm));
9569 /* Substitute ARGS into the vector or list of template arguments T. */
9572 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9575 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9578 if (t == error_mark_node)
9579 return error_mark_node;
9581 len = TREE_VEC_LENGTH (t);
9582 elts = XALLOCAVEC (tree, len);
9584 for (i = 0; i < len; i++)
9586 tree orig_arg = TREE_VEC_ELT (t, i);
9589 if (TREE_CODE (orig_arg) == TREE_VEC)
9590 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9591 else if (PACK_EXPANSION_P (orig_arg))
9593 /* Substitute into an expansion expression. */
9594 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9596 if (TREE_CODE (new_arg) == TREE_VEC)
9597 /* Add to the expanded length adjustment the number of
9598 expanded arguments. We subtract one from this
9599 measurement, because the argument pack expression
9600 itself is already counted as 1 in
9601 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9602 the argument pack is empty. */
9603 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9605 else if (ARGUMENT_PACK_P (orig_arg))
9607 /* Substitute into each of the arguments. */
9608 new_arg = TYPE_P (orig_arg)
9609 ? cxx_make_type (TREE_CODE (orig_arg))
9610 : make_node (TREE_CODE (orig_arg));
9612 SET_ARGUMENT_PACK_ARGS (
9614 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9615 args, complain, in_decl));
9617 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9618 new_arg = error_mark_node;
9620 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9621 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9623 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9625 if (TREE_TYPE (new_arg) == error_mark_node)
9626 new_arg = error_mark_node;
9630 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9632 if (new_arg == error_mark_node)
9633 return error_mark_node;
9636 if (new_arg != orig_arg)
9643 /* Make space for the expanded arguments coming from template
9645 t = make_tree_vec (len + expanded_len_adjust);
9646 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9647 arguments for a member template.
9648 In that case each TREE_VEC in ORIG_T represents a level of template
9649 arguments, and ORIG_T won't carry any non defaulted argument count.
9650 It will rather be the nested TREE_VECs that will carry one.
9651 In other words, ORIG_T carries a non defaulted argument count only
9652 if it doesn't contain any nested TREE_VEC. */
9653 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9655 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9656 count += expanded_len_adjust;
9657 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9659 for (i = 0, out = 0; i < len; i++)
9661 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9662 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9663 && TREE_CODE (elts[i]) == TREE_VEC)
9667 /* Now expand the template argument pack "in place". */
9668 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9669 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9673 TREE_VEC_ELT (t, out) = elts[i];
9681 /* Return the result of substituting ARGS into the template parameters
9682 given by PARMS. If there are m levels of ARGS and m + n levels of
9683 PARMS, then the result will contain n levels of PARMS. For
9684 example, if PARMS is `template <class T> template <class U>
9685 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9686 result will be `template <int*, double, class V>'. */
9689 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9694 /* When substituting into a template, we must set
9695 PROCESSING_TEMPLATE_DECL as the template parameters may be
9696 dependent if they are based on one-another, and the dependency
9697 predicates are short-circuit outside of templates. */
9698 ++processing_template_decl;
9700 for (new_parms = &r;
9701 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9702 new_parms = &(TREE_CHAIN (*new_parms)),
9703 parms = TREE_CHAIN (parms))
9706 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9709 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9713 if (parms == error_mark_node)
9716 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9718 if (tuple == error_mark_node)
9721 TREE_VEC_ELT (new_vec, i) =
9722 tsubst_template_parm (tuple, args, complain);
9726 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9727 - TMPL_ARGS_DEPTH (args)),
9728 new_vec, NULL_TREE);
9731 --processing_template_decl;
9736 /* Return the result of substituting ARGS into one template parameter
9737 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9738 parameter and which TREE_PURPOSE is the default argument of the
9739 template parameter. */
9742 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9744 tree default_value, parm_decl;
9746 if (args == NULL_TREE
9748 || t == error_mark_node)
9751 gcc_assert (TREE_CODE (t) == TREE_LIST);
9753 default_value = TREE_PURPOSE (t);
9754 parm_decl = TREE_VALUE (t);
9756 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9757 if (TREE_CODE (parm_decl) == PARM_DECL
9758 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9759 parm_decl = error_mark_node;
9760 default_value = tsubst_template_arg (default_value, args,
9761 complain, NULL_TREE);
9763 return build_tree_list (default_value, parm_decl);
9766 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9767 type T. If T is not an aggregate or enumeration type, it is
9768 handled as if by tsubst. IN_DECL is as for tsubst. If
9769 ENTERING_SCOPE is nonzero, T is the context for a template which
9770 we are presently tsubst'ing. Return the substituted value. */
9773 tsubst_aggr_type (tree t,
9775 tsubst_flags_t complain,
9782 switch (TREE_CODE (t))
9785 if (TYPE_PTRMEMFUNC_P (t))
9786 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9788 /* Else fall through. */
9791 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9796 int saved_unevaluated_operand;
9797 int saved_inhibit_evaluation_warnings;
9799 /* In "sizeof(X<I>)" we need to evaluate "I". */
9800 saved_unevaluated_operand = cp_unevaluated_operand;
9801 cp_unevaluated_operand = 0;
9802 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9803 c_inhibit_evaluation_warnings = 0;
9805 /* First, determine the context for the type we are looking
9807 context = TYPE_CONTEXT (t);
9808 if (context && TYPE_P (context))
9810 context = tsubst_aggr_type (context, args, complain,
9811 in_decl, /*entering_scope=*/1);
9812 /* If context is a nested class inside a class template,
9813 it may still need to be instantiated (c++/33959). */
9814 context = complete_type (context);
9817 /* Then, figure out what arguments are appropriate for the
9818 type we are trying to find. For example, given:
9820 template <class T> struct S;
9821 template <class T, class U> void f(T, U) { S<U> su; }
9823 and supposing that we are instantiating f<int, double>,
9824 then our ARGS will be {int, double}, but, when looking up
9825 S we only want {double}. */
9826 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9828 if (argvec == error_mark_node)
9829 r = error_mark_node;
9832 r = lookup_template_class (t, argvec, in_decl, context,
9833 entering_scope, complain);
9834 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9837 cp_unevaluated_operand = saved_unevaluated_operand;
9838 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9843 /* This is not a template type, so there's nothing to do. */
9847 return tsubst (t, args, complain, in_decl);
9851 /* Substitute into the default argument ARG (a default argument for
9852 FN), which has the indicated TYPE. */
9855 tsubst_default_argument (tree fn, tree type, tree arg)
9857 tree saved_class_ptr = NULL_TREE;
9858 tree saved_class_ref = NULL_TREE;
9860 /* This can happen in invalid code. */
9861 if (TREE_CODE (arg) == DEFAULT_ARG)
9864 /* This default argument came from a template. Instantiate the
9865 default argument here, not in tsubst. In the case of
9874 we must be careful to do name lookup in the scope of S<T>,
9875 rather than in the current class. */
9876 push_access_scope (fn);
9877 /* The "this" pointer is not valid in a default argument. */
9880 saved_class_ptr = current_class_ptr;
9881 cp_function_chain->x_current_class_ptr = NULL_TREE;
9882 saved_class_ref = current_class_ref;
9883 cp_function_chain->x_current_class_ref = NULL_TREE;
9886 push_deferring_access_checks(dk_no_deferred);
9887 /* The default argument expression may cause implicitly defined
9888 member functions to be synthesized, which will result in garbage
9889 collection. We must treat this situation as if we were within
9890 the body of function so as to avoid collecting live data on the
9893 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9894 tf_warning_or_error, NULL_TREE,
9895 /*integral_constant_expression_p=*/false);
9897 pop_deferring_access_checks();
9899 /* Restore the "this" pointer. */
9902 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9903 cp_function_chain->x_current_class_ref = saved_class_ref;
9906 /* Make sure the default argument is reasonable. */
9907 arg = check_default_argument (type, arg);
9909 pop_access_scope (fn);
9914 /* Substitute into all the default arguments for FN. */
9917 tsubst_default_arguments (tree fn)
9922 tmpl_args = DECL_TI_ARGS (fn);
9924 /* If this function is not yet instantiated, we certainly don't need
9925 its default arguments. */
9926 if (uses_template_parms (tmpl_args))
9928 /* Don't do this again for clones. */
9929 if (DECL_CLONED_FUNCTION_P (fn))
9932 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9934 arg = TREE_CHAIN (arg))
9935 if (TREE_PURPOSE (arg))
9936 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9938 TREE_PURPOSE (arg));
9941 /* Substitute the ARGS into the T, which is a _DECL. Return the
9942 result of the substitution. Issue error and warning messages under
9943 control of COMPLAIN. */
9946 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9948 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9949 location_t saved_loc;
9954 /* Set the filename and linenumber to improve error-reporting. */
9955 saved_loc = input_location;
9956 input_location = DECL_SOURCE_LOCATION (t);
9958 switch (TREE_CODE (t))
9962 /* We can get here when processing a member function template,
9963 member class template, or template template parameter. */
9964 tree decl = DECL_TEMPLATE_RESULT (t);
9969 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9971 /* Template template parameter is treated here. */
9972 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9973 if (new_type == error_mark_node)
9974 RETURN (error_mark_node);
9977 DECL_CHAIN (r) = NULL_TREE;
9978 TREE_TYPE (r) = new_type;
9979 DECL_TEMPLATE_RESULT (r)
9980 = build_decl (DECL_SOURCE_LOCATION (decl),
9981 TYPE_DECL, DECL_NAME (decl), new_type);
9982 DECL_TEMPLATE_PARMS (r)
9983 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9985 TYPE_NAME (new_type) = r;
9989 /* We might already have an instance of this template.
9990 The ARGS are for the surrounding class type, so the
9991 full args contain the tsubst'd args for the context,
9992 plus the innermost args from the template decl. */
9993 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9994 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9995 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9996 /* Because this is a template, the arguments will still be
9997 dependent, even after substitution. If
9998 PROCESSING_TEMPLATE_DECL is not set, the dependency
9999 predicates will short-circuit. */
10000 ++processing_template_decl;
10001 full_args = tsubst_template_args (tmpl_args, args,
10002 complain, in_decl);
10003 --processing_template_decl;
10004 if (full_args == error_mark_node)
10005 RETURN (error_mark_node);
10007 /* If this is a default template template argument,
10008 tsubst might not have changed anything. */
10009 if (full_args == tmpl_args)
10012 hash = hash_tmpl_and_args (t, full_args);
10013 spec = retrieve_specialization (t, full_args, hash);
10014 if (spec != NULL_TREE)
10020 /* Make a new template decl. It will be similar to the
10021 original, but will record the current template arguments.
10022 We also create a new function declaration, which is just
10023 like the old one, but points to this new template, rather
10024 than the old one. */
10026 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10027 DECL_CHAIN (r) = NULL_TREE;
10029 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10031 if (TREE_CODE (decl) == TYPE_DECL
10032 && !TYPE_DECL_ALIAS_P (decl))
10035 ++processing_template_decl;
10036 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10037 --processing_template_decl;
10038 if (new_type == error_mark_node)
10039 RETURN (error_mark_node);
10041 TREE_TYPE (r) = new_type;
10042 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10043 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10044 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10045 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10050 ++processing_template_decl;
10051 new_decl = tsubst (decl, args, complain, in_decl);
10052 --processing_template_decl;
10053 if (new_decl == error_mark_node)
10054 RETURN (error_mark_node);
10056 DECL_TEMPLATE_RESULT (r) = new_decl;
10057 DECL_TI_TEMPLATE (new_decl) = r;
10058 TREE_TYPE (r) = TREE_TYPE (new_decl);
10059 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10060 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10063 SET_DECL_IMPLICIT_INSTANTIATION (r);
10064 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10065 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10067 /* The template parameters for this new template are all the
10068 template parameters for the old template, except the
10069 outermost level of parameters. */
10070 DECL_TEMPLATE_PARMS (r)
10071 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10074 if (PRIMARY_TEMPLATE_P (t))
10075 DECL_PRIMARY_TEMPLATE (r) = r;
10077 if (TREE_CODE (decl) != TYPE_DECL)
10078 /* Record this non-type partial instantiation. */
10079 register_specialization (r, t,
10080 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10085 case FUNCTION_DECL:
10088 tree argvec = NULL_TREE;
10096 /* Nobody should be tsubst'ing into non-template functions. */
10097 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10099 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10104 /* If T is not dependent, just return it. We have to
10105 increment PROCESSING_TEMPLATE_DECL because
10106 value_dependent_expression_p assumes that nothing is
10107 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10108 ++processing_template_decl;
10109 dependent_p = value_dependent_expression_p (t);
10110 --processing_template_decl;
10114 /* Calculate the most general template of which R is a
10115 specialization, and the complete set of arguments used to
10117 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10118 argvec = tsubst_template_args (DECL_TI_ARGS
10119 (DECL_TEMPLATE_RESULT
10120 (DECL_TI_TEMPLATE (t))),
10121 args, complain, in_decl);
10122 if (argvec == error_mark_node)
10123 RETURN (error_mark_node);
10125 /* Check to see if we already have this specialization. */
10126 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10127 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10135 /* We can see more levels of arguments than parameters if
10136 there was a specialization of a member template, like
10139 template <class T> struct S { template <class U> void f(); }
10140 template <> template <class U> void S<int>::f(U);
10142 Here, we'll be substituting into the specialization,
10143 because that's where we can find the code we actually
10144 want to generate, but we'll have enough arguments for
10145 the most general template.
10147 We also deal with the peculiar case:
10149 template <class T> struct S {
10150 template <class U> friend void f();
10152 template <class U> void f() {}
10154 template void f<double>();
10156 Here, the ARGS for the instantiation of will be {int,
10157 double}. But, we only need as many ARGS as there are
10158 levels of template parameters in CODE_PATTERN. We are
10159 careful not to get fooled into reducing the ARGS in
10162 template <class T> struct S { template <class U> void f(U); }
10163 template <class T> template <> void S<T>::f(int) {}
10165 which we can spot because the pattern will be a
10166 specialization in this case. */
10167 args_depth = TMPL_ARGS_DEPTH (args);
10169 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10170 if (args_depth > parms_depth
10171 && !DECL_TEMPLATE_SPECIALIZATION (t))
10172 args = get_innermost_template_args (args, parms_depth);
10176 /* This special case arises when we have something like this:
10178 template <class T> struct S {
10179 friend void f<int>(int, double);
10182 Here, the DECL_TI_TEMPLATE for the friend declaration
10183 will be an IDENTIFIER_NODE. We are being called from
10184 tsubst_friend_function, and we want only to create a
10185 new decl (R) with appropriate types so that we can call
10186 determine_specialization. */
10187 gen_tmpl = NULL_TREE;
10190 if (DECL_CLASS_SCOPE_P (t))
10192 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10196 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10197 complain, t, /*entering_scope=*/1);
10202 ctx = DECL_CONTEXT (t);
10204 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10205 if (type == error_mark_node)
10206 RETURN (error_mark_node);
10208 /* We do NOT check for matching decls pushed separately at this
10209 point, as they may not represent instantiations of this
10210 template, and in any case are considered separate under the
10213 DECL_USE_TEMPLATE (r) = 0;
10214 TREE_TYPE (r) = type;
10215 /* Clear out the mangled name and RTL for the instantiation. */
10216 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10217 SET_DECL_RTL (r, NULL);
10218 /* Leave DECL_INITIAL set on deleted instantiations. */
10219 if (!DECL_DELETED_FN (r))
10220 DECL_INITIAL (r) = NULL_TREE;
10221 DECL_CONTEXT (r) = ctx;
10223 if (member && DECL_CONV_FN_P (r))
10224 /* Type-conversion operator. Reconstruct the name, in
10225 case it's the name of one of the template's parameters. */
10226 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10228 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10230 DECL_RESULT (r) = NULL_TREE;
10232 TREE_STATIC (r) = 0;
10233 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10234 DECL_EXTERNAL (r) = 1;
10235 /* If this is an instantiation of a function with internal
10236 linkage, we already know what object file linkage will be
10237 assigned to the instantiation. */
10238 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10239 DECL_DEFER_OUTPUT (r) = 0;
10240 DECL_CHAIN (r) = NULL_TREE;
10241 DECL_PENDING_INLINE_INFO (r) = 0;
10242 DECL_PENDING_INLINE_P (r) = 0;
10243 DECL_SAVED_TREE (r) = NULL_TREE;
10244 DECL_STRUCT_FUNCTION (r) = NULL;
10246 /* We'll re-clone as appropriate in instantiate_template. */
10247 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10249 /* If we aren't complaining now, return on error before we register
10250 the specialization so that we'll complain eventually. */
10251 if ((complain & tf_error) == 0
10252 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10253 && !grok_op_properties (r, /*complain=*/false))
10254 RETURN (error_mark_node);
10256 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10257 this in the special friend case mentioned above where
10258 GEN_TMPL is NULL. */
10261 DECL_TEMPLATE_INFO (r)
10262 = build_template_info (gen_tmpl, argvec);
10263 SET_DECL_IMPLICIT_INSTANTIATION (r);
10264 register_specialization (r, gen_tmpl, argvec, false, hash);
10266 /* We're not supposed to instantiate default arguments
10267 until they are called, for a template. But, for a
10270 template <class T> void f ()
10271 { extern void g(int i = T()); }
10273 we should do the substitution when the template is
10274 instantiated. We handle the member function case in
10275 instantiate_class_template since the default arguments
10276 might refer to other members of the class. */
10278 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10279 && !uses_template_parms (argvec))
10280 tsubst_default_arguments (r);
10283 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10285 /* Copy the list of befriending classes. */
10286 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10288 friends = &TREE_CHAIN (*friends))
10290 *friends = copy_node (*friends);
10291 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10296 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10298 maybe_retrofit_in_chrg (r);
10299 if (DECL_CONSTRUCTOR_P (r))
10300 grok_ctor_properties (ctx, r);
10301 /* If this is an instantiation of a member template, clone it.
10302 If it isn't, that'll be handled by
10303 clone_constructors_and_destructors. */
10304 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10305 clone_function_decl (r, /*update_method_vec_p=*/0);
10307 else if ((complain & tf_error) != 0
10308 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10309 && !grok_op_properties (r, /*complain=*/true))
10310 RETURN (error_mark_node);
10312 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10313 SET_DECL_FRIEND_CONTEXT (r,
10314 tsubst (DECL_FRIEND_CONTEXT (t),
10315 args, complain, in_decl));
10317 /* Possibly limit visibility based on template args. */
10318 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10319 if (DECL_VISIBILITY_SPECIFIED (t))
10321 DECL_VISIBILITY_SPECIFIED (r) = 0;
10322 DECL_ATTRIBUTES (r)
10323 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10325 determine_visibility (r);
10326 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10327 && !processing_template_decl)
10328 defaulted_late_check (r);
10330 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10331 args, complain, in_decl);
10337 tree type = NULL_TREE;
10339 tree expanded_types = NULL_TREE;
10340 tree prev_r = NULL_TREE;
10341 tree first_r = NULL_TREE;
10343 if (FUNCTION_PARAMETER_PACK_P (t))
10345 /* If there is a local specialization that isn't a
10346 parameter pack, it means that we're doing a "simple"
10347 substitution from inside tsubst_pack_expansion. Just
10348 return the local specialization (which will be a single
10350 tree spec = retrieve_local_specialization (t);
10352 && TREE_CODE (spec) == PARM_DECL
10353 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10356 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10357 the parameters in this function parameter pack. */
10358 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10359 complain, in_decl);
10360 if (TREE_CODE (expanded_types) == TREE_VEC)
10362 len = TREE_VEC_LENGTH (expanded_types);
10364 /* Zero-length parameter packs are boring. Just substitute
10367 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10372 /* All we did was update the type. Make a note of that. */
10373 type = expanded_types;
10374 expanded_types = NULL_TREE;
10378 /* Loop through all of the parameter's we'll build. When T is
10379 a function parameter pack, LEN is the number of expanded
10380 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10382 for (i = 0; i < len; ++i)
10386 if (DECL_TEMPLATE_PARM_P (t))
10387 SET_DECL_TEMPLATE_PARM_P (r);
10389 if (expanded_types)
10390 /* We're on the Ith parameter of the function parameter
10393 /* An argument of a function parameter pack is not a parameter
10395 FUNCTION_PARAMETER_PACK_P (r) = false;
10397 /* Get the Ith type. */
10398 type = TREE_VEC_ELT (expanded_types, i);
10401 /* Rename the parameter to include the index. */
10403 make_ith_pack_parameter_name (DECL_NAME (r), i);
10406 /* We're dealing with a normal parameter. */
10407 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10409 type = type_decays_to (type);
10410 TREE_TYPE (r) = type;
10411 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10413 if (DECL_INITIAL (r))
10415 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10416 DECL_INITIAL (r) = TREE_TYPE (r);
10418 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10419 complain, in_decl);
10422 DECL_CONTEXT (r) = NULL_TREE;
10424 if (!DECL_TEMPLATE_PARM_P (r))
10425 DECL_ARG_TYPE (r) = type_passed_as (type);
10427 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10428 args, complain, in_decl);
10430 /* Keep track of the first new parameter we
10431 generate. That's what will be returned to the
10436 /* Build a proper chain of parameters when substituting
10437 into a function parameter pack. */
10439 DECL_CHAIN (prev_r) = r;
10442 if (DECL_CHAIN (t))
10443 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10444 complain, DECL_CHAIN (t));
10446 /* FIRST_R contains the start of the chain we've built. */
10456 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10457 if (type == error_mark_node)
10458 RETURN (error_mark_node);
10459 TREE_TYPE (r) = type;
10460 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10462 if (DECL_C_BIT_FIELD (r))
10463 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10464 non-bit-fields DECL_INITIAL is a non-static data member
10465 initializer, which gets deferred instantiation. */
10467 = tsubst_expr (DECL_INITIAL (t), args,
10469 /*integral_constant_expression_p=*/true);
10470 else if (DECL_INITIAL (t))
10472 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10473 NSDMI in perform_member_init. Still set DECL_INITIAL
10474 so that we know there is one. */
10475 DECL_INITIAL (r) = void_zero_node;
10476 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10477 retrofit_lang_decl (r);
10478 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10480 /* We don't have to set DECL_CONTEXT here; it is set by
10481 finish_member_declaration. */
10482 DECL_CHAIN (r) = NULL_TREE;
10483 if (VOID_TYPE_P (type))
10484 error ("instantiation of %q+D as type %qT", r, type);
10486 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10487 args, complain, in_decl);
10492 /* We reach here only for member using decls. */
10493 if (DECL_DEPENDENT_P (t))
10495 r = do_class_using_decl
10496 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10497 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10499 r = error_mark_node;
10502 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10503 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10509 DECL_CHAIN (r) = NULL_TREE;
10516 tree argvec = NULL_TREE;
10517 tree gen_tmpl = NULL_TREE;
10519 tree tmpl = NULL_TREE;
10521 tree type = NULL_TREE;
10524 if (TREE_CODE (t) == TYPE_DECL
10525 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10527 /* If this is the canonical decl, we don't have to
10528 mess with instantiations, and often we can't (for
10529 typename, template type parms and such). Note that
10530 TYPE_NAME is not correct for the above test if
10531 we've copied the type for a typedef. */
10532 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10533 if (type == error_mark_node)
10534 RETURN (error_mark_node);
10535 r = TYPE_NAME (type);
10539 /* Check to see if we already have the specialization we
10542 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10544 /* T is a static data member or namespace-scope entity.
10545 We have to substitute into namespace-scope variables
10546 (even though such entities are never templates) because
10549 template <class T> void f() { extern T t; }
10551 where the entity referenced is not known until
10552 instantiation time. */
10554 ctx = DECL_CONTEXT (t);
10555 if (DECL_CLASS_SCOPE_P (t))
10557 ctx = tsubst_aggr_type (ctx, args,
10559 in_decl, /*entering_scope=*/1);
10560 /* If CTX is unchanged, then T is in fact the
10561 specialization we want. That situation occurs when
10562 referencing a static data member within in its own
10563 class. We can use pointer equality, rather than
10564 same_type_p, because DECL_CONTEXT is always
10566 if (ctx == DECL_CONTEXT (t)
10567 && (TREE_CODE (t) != TYPE_DECL
10568 /* ... unless T is a member template; in which
10569 case our caller can be willing to create a
10570 specialization of that template represented
10572 || !(DECL_TI_TEMPLATE (t)
10573 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10579 tmpl = DECL_TI_TEMPLATE (t);
10580 gen_tmpl = most_general_template (tmpl);
10581 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10582 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10583 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10588 /* A local variable. */
10590 /* Subsequent calls to pushdecl will fill this in. */
10592 spec = retrieve_local_specialization (t);
10594 /* If we already have the specialization we need, there is
10595 nothing more to do. */
10602 /* Create a new node for the specialization we need. */
10604 if (type == NULL_TREE)
10606 if (is_typedef_decl (t))
10607 type = DECL_ORIGINAL_TYPE (t);
10609 type = TREE_TYPE (t);
10610 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10611 type = strip_array_domain (type);
10612 type = tsubst (type, args, complain, in_decl);
10614 if (TREE_CODE (r) == VAR_DECL)
10616 /* Even if the original location is out of scope, the
10617 newly substituted one is not. */
10618 DECL_DEAD_FOR_LOCAL (r) = 0;
10619 DECL_INITIALIZED_P (r) = 0;
10620 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10621 if (type == error_mark_node)
10622 RETURN (error_mark_node);
10623 if (TREE_CODE (type) == FUNCTION_TYPE)
10625 /* It may seem that this case cannot occur, since:
10630 declares a function, not a variable. However:
10633 template <typename T> void g() { T t; }
10634 template void g<f>();
10636 is an attempt to declare a variable with function
10638 error ("variable %qD has function type",
10639 /* R is not yet sufficiently initialized, so we
10640 just use its name. */
10642 RETURN (error_mark_node);
10644 type = complete_type (type);
10645 /* Wait until cp_finish_decl to set this again, to handle
10646 circular dependency (template/instantiate6.C). */
10647 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10648 type = check_var_type (DECL_NAME (r), type);
10650 if (DECL_HAS_VALUE_EXPR_P (t))
10652 tree ve = DECL_VALUE_EXPR (t);
10653 ve = tsubst_expr (ve, args, complain, in_decl,
10654 /*constant_expression_p=*/false);
10655 if (REFERENCE_REF_P (ve))
10657 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10658 ve = TREE_OPERAND (ve, 0);
10660 SET_DECL_VALUE_EXPR (r, ve);
10663 else if (DECL_SELF_REFERENCE_P (t))
10664 SET_DECL_SELF_REFERENCE_P (r);
10665 TREE_TYPE (r) = type;
10666 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10667 DECL_CONTEXT (r) = ctx;
10668 /* Clear out the mangled name and RTL for the instantiation. */
10669 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10670 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10671 SET_DECL_RTL (r, NULL);
10672 /* The initializer must not be expanded until it is required;
10673 see [temp.inst]. */
10674 DECL_INITIAL (r) = NULL_TREE;
10675 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10676 SET_DECL_RTL (r, NULL);
10677 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10678 if (TREE_CODE (r) == VAR_DECL)
10680 /* Possibly limit visibility based on template args. */
10681 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10682 if (DECL_VISIBILITY_SPECIFIED (t))
10684 DECL_VISIBILITY_SPECIFIED (r) = 0;
10685 DECL_ATTRIBUTES (r)
10686 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10688 determine_visibility (r);
10693 /* A static data member declaration is always marked
10694 external when it is declared in-class, even if an
10695 initializer is present. We mimic the non-template
10696 processing here. */
10697 DECL_EXTERNAL (r) = 1;
10699 register_specialization (r, gen_tmpl, argvec, false, hash);
10700 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10701 SET_DECL_IMPLICIT_INSTANTIATION (r);
10703 else if (cp_unevaluated_operand)
10705 /* We're substituting this var in a decltype outside of its
10706 scope, such as for a lambda return type. Don't add it to
10707 local_specializations, do perform auto deduction. */
10708 tree auto_node = type_uses_auto (type);
10712 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10713 /*constant_expression_p=*/false);
10714 init = resolve_nondeduced_context (init);
10715 TREE_TYPE (r) = type
10716 = do_auto_deduction (type, init, auto_node);
10720 register_local_specialization (r, t);
10722 DECL_CHAIN (r) = NULL_TREE;
10724 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10726 args, complain, in_decl);
10728 /* Preserve a typedef that names a type. */
10729 if (is_typedef_decl (r))
10731 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10732 set_underlying_type (r);
10735 layout_decl (r, 0);
10740 gcc_unreachable ();
10745 /* Restore the file and line information. */
10746 input_location = saved_loc;
10751 /* Substitute into the ARG_TYPES of a function type. */
10754 tsubst_arg_types (tree arg_types,
10756 tsubst_flags_t complain,
10759 tree remaining_arg_types;
10760 tree type = NULL_TREE;
10762 tree expanded_args = NULL_TREE;
10765 if (!arg_types || arg_types == void_list_node)
10768 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10769 args, complain, in_decl);
10770 if (remaining_arg_types == error_mark_node)
10771 return error_mark_node;
10773 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10775 /* For a pack expansion, perform substitution on the
10776 entire expression. Later on, we'll handle the arguments
10778 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10779 args, complain, in_decl);
10781 if (TREE_CODE (expanded_args) == TREE_VEC)
10782 /* So that we'll spin through the parameters, one by one. */
10783 i = TREE_VEC_LENGTH (expanded_args);
10786 /* We only partially substituted into the parameter
10787 pack. Our type is TYPE_PACK_EXPANSION. */
10788 type = expanded_args;
10789 expanded_args = NULL_TREE;
10797 type = TREE_VEC_ELT (expanded_args, i);
10799 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10801 if (type == error_mark_node)
10802 return error_mark_node;
10803 if (VOID_TYPE_P (type))
10805 if (complain & tf_error)
10807 error ("invalid parameter type %qT", type);
10809 error ("in declaration %q+D", in_decl);
10811 return error_mark_node;
10814 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10815 top-level qualifiers as required. */
10816 type = cv_unqualified (type_decays_to (type));
10818 /* We do not substitute into default arguments here. The standard
10819 mandates that they be instantiated only when needed, which is
10820 done in build_over_call. */
10821 default_arg = TREE_PURPOSE (arg_types);
10823 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10825 /* We've instantiated a template before its default arguments
10826 have been parsed. This can happen for a nested template
10827 class, and is not an error unless we require the default
10828 argument in a call of this function. */
10829 remaining_arg_types =
10830 tree_cons (default_arg, type, remaining_arg_types);
10831 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10832 remaining_arg_types);
10835 remaining_arg_types =
10836 hash_tree_cons (default_arg, type, remaining_arg_types);
10839 return remaining_arg_types;
10842 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10843 *not* handle the exception-specification for FNTYPE, because the
10844 initial substitution of explicitly provided template parameters
10845 during argument deduction forbids substitution into the
10846 exception-specification:
10850 All references in the function type of the function template to the
10851 corresponding template parameters are replaced by the specified tem-
10852 plate argument values. If a substitution in a template parameter or
10853 in the function type of the function template results in an invalid
10854 type, type deduction fails. [Note: The equivalent substitution in
10855 exception specifications is done only when the function is instanti-
10856 ated, at which point a program is ill-formed if the substitution
10857 results in an invalid type.] */
10860 tsubst_function_type (tree t,
10862 tsubst_flags_t complain,
10869 /* The TYPE_CONTEXT is not used for function/method types. */
10870 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10872 /* Substitute the return type. */
10873 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10874 if (return_type == error_mark_node)
10875 return error_mark_node;
10876 /* The standard does not presently indicate that creation of a
10877 function type with an invalid return type is a deduction failure.
10878 However, that is clearly analogous to creating an array of "void"
10879 or a reference to a reference. This is core issue #486. */
10880 if (TREE_CODE (return_type) == ARRAY_TYPE
10881 || TREE_CODE (return_type) == FUNCTION_TYPE)
10883 if (complain & tf_error)
10885 if (TREE_CODE (return_type) == ARRAY_TYPE)
10886 error ("function returning an array");
10888 error ("function returning a function");
10890 return error_mark_node;
10893 /* Substitute the argument types. */
10894 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10895 complain, in_decl);
10896 if (arg_types == error_mark_node)
10897 return error_mark_node;
10899 /* Construct a new type node and return it. */
10900 if (TREE_CODE (t) == FUNCTION_TYPE)
10902 fntype = build_function_type (return_type, arg_types);
10903 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10907 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10908 if (! MAYBE_CLASS_TYPE_P (r))
10912 Type deduction may fail for any of the following
10915 -- Attempting to create "pointer to member of T" when T
10916 is not a class type. */
10917 if (complain & tf_error)
10918 error ("creating pointer to member function of non-class type %qT",
10920 return error_mark_node;
10923 fntype = build_method_type_directly (r, return_type,
10924 TREE_CHAIN (arg_types));
10926 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10931 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10932 ARGS into that specification, and return the substituted
10933 specification. If there is no specification, return NULL_TREE. */
10936 tsubst_exception_specification (tree fntype,
10938 tsubst_flags_t complain,
10945 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10946 new_specs = NULL_TREE;
10947 if (specs && TREE_PURPOSE (specs))
10949 /* A noexcept-specifier. */
10950 tree expr = TREE_PURPOSE (specs);
10951 if (expr == boolean_true_node || expr == boolean_false_node)
10955 /* Defer instantiation of noexcept-specifiers to avoid
10956 excessive instantiations (c++/49107). */
10957 new_specs = make_node (DEFERRED_NOEXCEPT);
10958 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
10960 /* We already partially instantiated this member template,
10961 so combine the new args with the old. */
10962 DEFERRED_NOEXCEPT_PATTERN (new_specs)
10963 = DEFERRED_NOEXCEPT_PATTERN (expr);
10964 DEFERRED_NOEXCEPT_ARGS (new_specs)
10965 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
10969 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
10970 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
10974 new_specs = tsubst_copy_and_build
10975 (expr, args, complain, in_decl, /*function_p=*/false,
10976 /*integral_constant_expression_p=*/true);
10977 new_specs = build_noexcept_spec (new_specs, complain);
10981 if (! TREE_VALUE (specs))
10988 tree expanded_specs = NULL_TREE;
10990 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10992 /* Expand the pack expansion type. */
10993 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10997 if (expanded_specs == error_mark_node)
10998 return error_mark_node;
10999 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11000 len = TREE_VEC_LENGTH (expanded_specs);
11003 /* We're substituting into a member template, so
11004 we got a TYPE_PACK_EXPANSION back. Add that
11005 expansion and move on. */
11006 gcc_assert (TREE_CODE (expanded_specs)
11007 == TYPE_PACK_EXPANSION);
11008 new_specs = add_exception_specifier (new_specs,
11011 specs = TREE_CHAIN (specs);
11016 for (i = 0; i < len; ++i)
11018 if (expanded_specs)
11019 spec = TREE_VEC_ELT (expanded_specs, i);
11021 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11022 if (spec == error_mark_node)
11024 new_specs = add_exception_specifier (new_specs, spec,
11028 specs = TREE_CHAIN (specs);
11034 /* Take the tree structure T and replace template parameters used
11035 therein with the argument vector ARGS. IN_DECL is an associated
11036 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11037 Issue error and warning messages under control of COMPLAIN. Note
11038 that we must be relatively non-tolerant of extensions here, in
11039 order to preserve conformance; if we allow substitutions that
11040 should not be allowed, we may allow argument deductions that should
11041 not succeed, and therefore report ambiguous overload situations
11042 where there are none. In theory, we could allow the substitution,
11043 but indicate that it should have failed, and allow our caller to
11044 make sure that the right thing happens, but we don't try to do this
11047 This function is used for dealing with types, decls and the like;
11048 for expressions, use tsubst_expr or tsubst_copy. */
11051 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11053 enum tree_code code;
11054 tree type, r = NULL_TREE;
11056 if (t == NULL_TREE || t == error_mark_node
11057 || t == integer_type_node
11058 || t == void_type_node
11059 || t == char_type_node
11060 || t == unknown_type_node
11061 || TREE_CODE (t) == NAMESPACE_DECL
11062 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11066 return tsubst_decl (t, args, complain);
11068 if (args == NULL_TREE)
11071 code = TREE_CODE (t);
11073 if (code == IDENTIFIER_NODE)
11074 type = IDENTIFIER_TYPE_VALUE (t);
11076 type = TREE_TYPE (t);
11078 gcc_assert (type != unknown_type_node);
11080 /* Reuse typedefs. We need to do this to handle dependent attributes,
11081 such as attribute aligned. */
11083 && typedef_variant_p (t))
11085 tree decl = TYPE_NAME (t);
11087 if (TYPE_DECL_ALIAS_P (decl)
11088 && DECL_LANG_SPECIFIC (decl)
11089 && DECL_TEMPLATE_INFO (decl)
11090 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11092 /* DECL represents an alias template and we want to
11093 instantiate it. Let's substitute our arguments for the
11094 template parameters into the declaration and get the
11096 r = tsubst (decl, args, complain, decl);
11098 else if (DECL_CLASS_SCOPE_P (decl)
11099 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11100 && uses_template_parms (DECL_CONTEXT (decl)))
11102 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11103 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11104 r = retrieve_specialization (tmpl, gen_args, 0);
11106 else if (DECL_FUNCTION_SCOPE_P (decl)
11107 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11108 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11109 r = retrieve_local_specialization (decl);
11111 /* The typedef is from a non-template context. */
11117 r = cp_build_qualified_type_real
11118 (r, cp_type_quals (t) | cp_type_quals (r),
11119 complain | tf_ignore_bad_quals);
11122 /* Else we must be instantiating the typedef, so fall through. */
11126 && code != TYPENAME_TYPE
11127 && code != TEMPLATE_TYPE_PARM
11128 && code != IDENTIFIER_NODE
11129 && code != FUNCTION_TYPE
11130 && code != METHOD_TYPE)
11131 type = tsubst (type, args, complain, in_decl);
11132 if (type == error_mark_node)
11133 return error_mark_node;
11139 case ENUMERAL_TYPE:
11140 return tsubst_aggr_type (t, args, complain, in_decl,
11141 /*entering_scope=*/0);
11144 case IDENTIFIER_NODE:
11155 if (t == integer_type_node)
11158 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11159 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11163 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11165 max = tsubst_expr (omax, args, complain, in_decl,
11166 /*integral_constant_expression_p=*/false);
11168 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11170 if (TREE_CODE (max) == NOP_EXPR
11171 && TREE_SIDE_EFFECTS (omax)
11172 && !TREE_TYPE (max))
11173 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11175 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11176 with TREE_SIDE_EFFECTS that indicates this is not an integral
11177 constant expression. */
11178 if (processing_template_decl
11179 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11181 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11182 TREE_SIDE_EFFECTS (max) = 1;
11185 return compute_array_index_type (NULL_TREE, max, complain);
11188 case TEMPLATE_TYPE_PARM:
11189 case TEMPLATE_TEMPLATE_PARM:
11190 case BOUND_TEMPLATE_TEMPLATE_PARM:
11191 case TEMPLATE_PARM_INDEX:
11196 tree arg = NULL_TREE;
11200 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11201 template_parm_level_and_index (t, &level, &idx);
11203 levels = TMPL_ARGS_DEPTH (args);
11204 if (level <= levels)
11206 arg = TMPL_ARG (args, level, idx);
11208 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11209 /* See through ARGUMENT_PACK_SELECT arguments. */
11210 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11213 if (arg == error_mark_node)
11214 return error_mark_node;
11215 else if (arg != NULL_TREE)
11217 if (ARGUMENT_PACK_P (arg))
11218 /* If ARG is an argument pack, we don't actually want to
11219 perform a substitution here, because substitutions
11220 for argument packs are only done
11221 element-by-element. We can get to this point when
11222 substituting the type of a non-type template
11223 parameter pack, when that type actually contains
11224 template parameter packs from an outer template, e.g.,
11226 template<typename... Types> struct A {
11227 template<Types... Values> struct B { };
11231 if (code == TEMPLATE_TYPE_PARM)
11234 gcc_assert (TYPE_P (arg));
11236 quals = cp_type_quals (arg) | cp_type_quals (t);
11238 return cp_build_qualified_type_real
11239 (arg, quals, complain | tf_ignore_bad_quals);
11241 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11243 /* We are processing a type constructed from a
11244 template template parameter. */
11245 tree argvec = tsubst (TYPE_TI_ARGS (t),
11246 args, complain, in_decl);
11247 if (argvec == error_mark_node)
11248 return error_mark_node;
11250 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11251 || TREE_CODE (arg) == TEMPLATE_DECL
11252 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11254 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11255 /* Consider this code:
11257 template <template <class> class Template>
11259 template <class Arg> using Bind = Template<Arg>;
11262 template <template <class> class Template, class Arg>
11263 using Instantiate = Template<Arg>; //#0
11265 template <template <class> class Template,
11268 Instantiate<Internal<Template>::template Bind,
11271 When #1 is parsed, the
11272 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11273 parameter `Template' in #0 matches the
11274 UNBOUND_CLASS_TEMPLATE representing the argument
11275 `Internal<Template>::template Bind'; We then want
11276 to assemble the type `Bind<Argument>' that can't
11277 be fully created right now, because
11278 `Internal<Template>' not being complete, the Bind
11279 template cannot be looked up in that context. So
11280 we need to "store" `Bind<Argument>' for later
11281 when the context of Bind becomes complete. Let's
11282 store that in a TYPENAME_TYPE. */
11283 return make_typename_type (TYPE_CONTEXT (arg),
11284 build_nt (TEMPLATE_ID_EXPR,
11285 TYPE_IDENTIFIER (arg),
11290 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11291 are resolving nested-types in the signature of a
11292 member function templates. Otherwise ARG is a
11293 TEMPLATE_DECL and is the real template to be
11295 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11296 arg = TYPE_NAME (arg);
11298 r = lookup_template_class (arg,
11300 DECL_CONTEXT (arg),
11301 /*entering_scope=*/0,
11303 return cp_build_qualified_type_real
11304 (r, cp_type_quals (t), complain);
11307 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11308 return convert_from_reference (unshare_expr (arg));
11312 /* This can happen during the attempted tsubst'ing in
11313 unify. This means that we don't yet have any information
11314 about the template parameter in question. */
11317 /* If we get here, we must have been looking at a parm for a
11318 more deeply nested template. Make a new version of this
11319 template parameter, but with a lower level. */
11322 case TEMPLATE_TYPE_PARM:
11323 case TEMPLATE_TEMPLATE_PARM:
11324 case BOUND_TEMPLATE_TEMPLATE_PARM:
11325 if (cp_type_quals (t))
11327 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11328 r = cp_build_qualified_type_real
11329 (r, cp_type_quals (t),
11330 complain | (code == TEMPLATE_TYPE_PARM
11331 ? tf_ignore_bad_quals : 0));
11336 TEMPLATE_TYPE_PARM_INDEX (r)
11337 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11338 r, levels, args, complain);
11339 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11340 TYPE_MAIN_VARIANT (r) = r;
11341 TYPE_POINTER_TO (r) = NULL_TREE;
11342 TYPE_REFERENCE_TO (r) = NULL_TREE;
11344 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11345 /* We have reduced the level of the template
11346 template parameter, but not the levels of its
11347 template parameters, so canonical_type_parameter
11348 will not be able to find the canonical template
11349 template parameter for this level. Thus, we
11350 require structural equality checking to compare
11351 TEMPLATE_TEMPLATE_PARMs. */
11352 SET_TYPE_STRUCTURAL_EQUALITY (r);
11353 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11354 SET_TYPE_STRUCTURAL_EQUALITY (r);
11356 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11358 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11360 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11361 complain, in_decl);
11362 if (argvec == error_mark_node)
11363 return error_mark_node;
11365 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11366 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11371 case TEMPLATE_PARM_INDEX:
11372 r = reduce_template_parm_level (t, type, levels, args, complain);
11376 gcc_unreachable ();
11384 tree purpose, value, chain;
11386 if (t == void_list_node)
11389 purpose = TREE_PURPOSE (t);
11392 purpose = tsubst (purpose, args, complain, in_decl);
11393 if (purpose == error_mark_node)
11394 return error_mark_node;
11396 value = TREE_VALUE (t);
11399 value = tsubst (value, args, complain, in_decl);
11400 if (value == error_mark_node)
11401 return error_mark_node;
11403 chain = TREE_CHAIN (t);
11404 if (chain && chain != void_type_node)
11406 chain = tsubst (chain, args, complain, in_decl);
11407 if (chain == error_mark_node)
11408 return error_mark_node;
11410 if (purpose == TREE_PURPOSE (t)
11411 && value == TREE_VALUE (t)
11412 && chain == TREE_CHAIN (t))
11414 return hash_tree_cons (purpose, value, chain);
11418 /* We should never be tsubsting a binfo. */
11419 gcc_unreachable ();
11422 /* A vector of template arguments. */
11423 gcc_assert (!type);
11424 return tsubst_template_args (t, args, complain, in_decl);
11427 case REFERENCE_TYPE:
11429 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11434 Type deduction may fail for any of the following
11437 -- Attempting to create a pointer to reference type.
11438 -- Attempting to create a reference to a reference type or
11439 a reference to void.
11441 Core issue 106 says that creating a reference to a reference
11442 during instantiation is no longer a cause for failure. We
11443 only enforce this check in strict C++98 mode. */
11444 if ((TREE_CODE (type) == REFERENCE_TYPE
11445 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11446 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11448 static location_t last_loc;
11450 /* We keep track of the last time we issued this error
11451 message to avoid spewing a ton of messages during a
11452 single bad template instantiation. */
11453 if (complain & tf_error
11454 && last_loc != input_location)
11456 if (TREE_CODE (type) == VOID_TYPE)
11457 error ("forming reference to void");
11458 else if (code == POINTER_TYPE)
11459 error ("forming pointer to reference type %qT", type);
11461 error ("forming reference to reference type %qT", type);
11462 last_loc = input_location;
11465 return error_mark_node;
11467 else if (code == POINTER_TYPE)
11469 r = build_pointer_type (type);
11470 if (TREE_CODE (type) == METHOD_TYPE)
11471 r = build_ptrmemfunc_type (r);
11473 else if (TREE_CODE (type) == REFERENCE_TYPE)
11474 /* In C++0x, during template argument substitution, when there is an
11475 attempt to create a reference to a reference type, reference
11476 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11478 "If a template-argument for a template-parameter T names a type
11479 that is a reference to a type A, an attempt to create the type
11480 'lvalue reference to cv T' creates the type 'lvalue reference to
11481 A,' while an attempt to create the type type rvalue reference to
11482 cv T' creates the type T"
11484 r = cp_build_reference_type
11486 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11488 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11489 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11491 if (r != error_mark_node)
11492 /* Will this ever be needed for TYPE_..._TO values? */
11499 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11500 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11504 Type deduction may fail for any of the following
11507 -- Attempting to create "pointer to member of T" when T
11508 is not a class type. */
11509 if (complain & tf_error)
11510 error ("creating pointer to member of non-class type %qT", r);
11511 return error_mark_node;
11513 if (TREE_CODE (type) == REFERENCE_TYPE)
11515 if (complain & tf_error)
11516 error ("creating pointer to member reference type %qT", type);
11517 return error_mark_node;
11519 if (TREE_CODE (type) == VOID_TYPE)
11521 if (complain & tf_error)
11522 error ("creating pointer to member of type void");
11523 return error_mark_node;
11525 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11526 if (TREE_CODE (type) == FUNCTION_TYPE)
11528 /* The type of the implicit object parameter gets its
11529 cv-qualifiers from the FUNCTION_TYPE. */
11531 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11532 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11533 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11537 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11541 case FUNCTION_TYPE:
11546 fntype = tsubst_function_type (t, args, complain, in_decl);
11547 if (fntype == error_mark_node)
11548 return error_mark_node;
11550 /* Substitute the exception specification. */
11551 specs = tsubst_exception_specification (t, args, complain,
11552 in_decl, /*defer_ok*/true);
11553 if (specs == error_mark_node)
11554 return error_mark_node;
11556 fntype = build_exception_variant (fntype, specs);
11561 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11562 if (domain == error_mark_node)
11563 return error_mark_node;
11565 /* As an optimization, we avoid regenerating the array type if
11566 it will obviously be the same as T. */
11567 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11570 /* These checks should match the ones in grokdeclarator.
11574 The deduction may fail for any of the following reasons:
11576 -- Attempting to create an array with an element type that
11577 is void, a function type, or a reference type, or [DR337]
11578 an abstract class type. */
11579 if (TREE_CODE (type) == VOID_TYPE
11580 || TREE_CODE (type) == FUNCTION_TYPE
11581 || TREE_CODE (type) == REFERENCE_TYPE)
11583 if (complain & tf_error)
11584 error ("creating array of %qT", type);
11585 return error_mark_node;
11587 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11589 if (complain & tf_error)
11590 error ("creating array of %qT, which is an abstract class type",
11592 return error_mark_node;
11595 r = build_cplus_array_type (type, domain);
11597 if (TYPE_USER_ALIGN (t))
11599 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11600 TYPE_USER_ALIGN (r) = 1;
11606 case TYPENAME_TYPE:
11608 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11609 in_decl, /*entering_scope=*/1);
11610 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11611 complain, in_decl);
11613 if (ctx == error_mark_node || f == error_mark_node)
11614 return error_mark_node;
11616 if (!MAYBE_CLASS_TYPE_P (ctx))
11618 if (complain & tf_error)
11619 error ("%qT is not a class, struct, or union type", ctx);
11620 return error_mark_node;
11622 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11624 /* Normally, make_typename_type does not require that the CTX
11625 have complete type in order to allow things like:
11627 template <class T> struct S { typename S<T>::X Y; };
11629 But, such constructs have already been resolved by this
11630 point, so here CTX really should have complete type, unless
11631 it's a partial instantiation. */
11632 ctx = complete_type (ctx);
11633 if (!COMPLETE_TYPE_P (ctx))
11635 if (complain & tf_error)
11636 cxx_incomplete_type_error (NULL_TREE, ctx);
11637 return error_mark_node;
11641 f = make_typename_type (ctx, f, typename_type,
11642 (complain & tf_error) | tf_keep_type_decl);
11643 if (f == error_mark_node)
11645 if (TREE_CODE (f) == TYPE_DECL)
11647 complain |= tf_ignore_bad_quals;
11651 if (TREE_CODE (f) != TYPENAME_TYPE)
11653 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11655 if (complain & tf_error)
11656 error ("%qT resolves to %qT, which is not an enumeration type",
11659 return error_mark_node;
11661 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11663 if (complain & tf_error)
11664 error ("%qT resolves to %qT, which is is not a class type",
11667 return error_mark_node;
11671 return cp_build_qualified_type_real
11672 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11675 case UNBOUND_CLASS_TEMPLATE:
11677 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11678 in_decl, /*entering_scope=*/1);
11679 tree name = TYPE_IDENTIFIER (t);
11680 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11682 if (ctx == error_mark_node || name == error_mark_node)
11683 return error_mark_node;
11686 parm_list = tsubst_template_parms (parm_list, args, complain);
11687 return make_unbound_class_template (ctx, name, parm_list, complain);
11694 ++cp_unevaluated_operand;
11695 ++c_inhibit_evaluation_warnings;
11697 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11699 /*integral_constant_expression_p=*/false);
11701 --cp_unevaluated_operand;
11702 --c_inhibit_evaluation_warnings;
11704 type = finish_typeof (type);
11705 return cp_build_qualified_type_real (type,
11707 | cp_type_quals (type),
11711 case DECLTYPE_TYPE:
11715 ++cp_unevaluated_operand;
11716 ++c_inhibit_evaluation_warnings;
11718 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11720 /*integral_constant_expression_p=*/false);
11722 --cp_unevaluated_operand;
11723 --c_inhibit_evaluation_warnings;
11725 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11726 type = lambda_capture_field_type (type);
11727 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11728 type = lambda_proxy_type (type);
11730 type = finish_decltype_type
11731 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11732 return cp_build_qualified_type_real (type,
11734 | cp_type_quals (type),
11738 case UNDERLYING_TYPE:
11740 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11741 complain, in_decl);
11742 return finish_underlying_type (type);
11745 case TYPE_ARGUMENT_PACK:
11746 case NONTYPE_ARGUMENT_PACK:
11748 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11750 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11754 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11756 /* For template nontype argument packs, also substitute into
11758 if (code == NONTYPE_ARGUMENT_PACK)
11759 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11777 /* We should use one of the expression tsubsts for these codes. */
11778 gcc_unreachable ();
11781 sorry ("use of %qs in template", tree_code_name [(int) code]);
11782 return error_mark_node;
11786 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11787 type of the expression on the left-hand side of the "." or "->"
11791 tsubst_baselink (tree baselink, tree object_type,
11792 tree args, tsubst_flags_t complain, tree in_decl)
11795 tree qualifying_scope;
11798 tree template_args = 0;
11799 bool template_id_p = false;
11801 /* A baselink indicates a function from a base class. Both the
11802 BASELINK_ACCESS_BINFO and the base class referenced may
11803 indicate bases of the template class, rather than the
11804 instantiated class. In addition, lookups that were not
11805 ambiguous before may be ambiguous now. Therefore, we perform
11806 the lookup again. */
11807 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11808 qualifying_scope = tsubst (qualifying_scope, args,
11809 complain, in_decl);
11810 fns = BASELINK_FUNCTIONS (baselink);
11811 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11812 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11814 template_id_p = true;
11815 template_args = TREE_OPERAND (fns, 1);
11816 fns = TREE_OPERAND (fns, 0);
11818 template_args = tsubst_template_args (template_args, args,
11819 complain, in_decl);
11821 name = DECL_NAME (get_first_fn (fns));
11822 if (IDENTIFIER_TYPENAME_P (name))
11823 name = mangle_conv_op_name_for_type (optype);
11824 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11826 return error_mark_node;
11828 /* If lookup found a single function, mark it as used at this
11829 point. (If it lookup found multiple functions the one selected
11830 later by overload resolution will be marked as used at that
11832 if (BASELINK_P (baselink))
11833 fns = BASELINK_FUNCTIONS (baselink);
11834 if (!template_id_p && !really_overloaded_fn (fns))
11835 mark_used (OVL_CURRENT (fns));
11837 /* Add back the template arguments, if present. */
11838 if (BASELINK_P (baselink) && template_id_p)
11839 BASELINK_FUNCTIONS (baselink)
11840 = build_nt (TEMPLATE_ID_EXPR,
11841 BASELINK_FUNCTIONS (baselink),
11843 /* Update the conversion operator type. */
11844 BASELINK_OPTYPE (baselink) = optype;
11847 object_type = current_class_type;
11848 return adjust_result_of_qualified_name_lookup (baselink,
11853 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11854 true if the qualified-id will be a postfix-expression in-and-of
11855 itself; false if more of the postfix-expression follows the
11856 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11860 tsubst_qualified_id (tree qualified_id, tree args,
11861 tsubst_flags_t complain, tree in_decl,
11862 bool done, bool address_p)
11868 tree template_args;
11870 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11872 /* Figure out what name to look up. */
11873 name = TREE_OPERAND (qualified_id, 1);
11874 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11876 is_template = true;
11877 template_args = TREE_OPERAND (name, 1);
11879 template_args = tsubst_template_args (template_args, args,
11880 complain, in_decl);
11881 name = TREE_OPERAND (name, 0);
11885 is_template = false;
11886 template_args = NULL_TREE;
11889 /* Substitute into the qualifying scope. When there are no ARGS, we
11890 are just trying to simplify a non-dependent expression. In that
11891 case the qualifying scope may be dependent, and, in any case,
11892 substituting will not help. */
11893 scope = TREE_OPERAND (qualified_id, 0);
11896 scope = tsubst (scope, args, complain, in_decl);
11897 expr = tsubst_copy (name, args, complain, in_decl);
11902 if (dependent_scope_p (scope))
11905 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11906 return build_qualified_name (NULL_TREE, scope, expr,
11907 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11910 if (!BASELINK_P (name) && !DECL_P (expr))
11912 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11914 /* A BIT_NOT_EXPR is used to represent a destructor. */
11915 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11917 error ("qualifying type %qT does not match destructor name ~%qT",
11918 scope, TREE_OPERAND (expr, 0));
11919 expr = error_mark_node;
11922 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11923 /*is_type_p=*/0, false);
11926 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11927 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11928 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11930 if (complain & tf_error)
11932 error ("dependent-name %qE is parsed as a non-type, but "
11933 "instantiation yields a type", qualified_id);
11934 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11936 return error_mark_node;
11942 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11944 /* Remember that there was a reference to this entity. */
11948 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11950 if (complain & tf_error)
11951 qualified_name_lookup_error (scope,
11952 TREE_OPERAND (qualified_id, 1),
11953 expr, input_location);
11954 return error_mark_node;
11958 expr = lookup_template_function (expr, template_args);
11960 if (expr == error_mark_node && complain & tf_error)
11961 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11962 expr, input_location);
11963 else if (TYPE_P (scope))
11965 expr = (adjust_result_of_qualified_name_lookup
11966 (expr, scope, current_class_type));
11967 expr = (finish_qualified_id_expr
11968 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
11969 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11970 /*template_arg_p=*/false));
11973 /* Expressions do not generally have reference type. */
11974 if (TREE_CODE (expr) != SCOPE_REF
11975 /* However, if we're about to form a pointer-to-member, we just
11976 want the referenced member referenced. */
11977 && TREE_CODE (expr) != OFFSET_REF)
11978 expr = convert_from_reference (expr);
11983 /* Like tsubst, but deals with expressions. This function just replaces
11984 template parms; to finish processing the resultant expression, use
11985 tsubst_copy_and_build or tsubst_expr. */
11988 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11990 enum tree_code code;
11993 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11996 code = TREE_CODE (t);
12001 r = retrieve_local_specialization (t);
12007 /* We get here for a use of 'this' in an NSDMI. */
12008 if (DECL_NAME (t) == this_identifier
12009 && at_function_scope_p ()
12010 && DECL_CONSTRUCTOR_P (current_function_decl))
12011 return current_class_ptr;
12013 /* This can happen for a parameter name used later in a function
12014 declaration (such as in a late-specified return type). Just
12015 make a dummy decl, since it's only used for its type. */
12016 gcc_assert (cp_unevaluated_operand != 0);
12017 /* We copy T because want to tsubst the PARM_DECL only,
12018 not the following PARM_DECLs that are chained to T. */
12020 r = tsubst_decl (c, args, complain);
12021 /* Give it the template pattern as its context; its true context
12022 hasn't been instantiated yet and this is good enough for
12024 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12027 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12028 r = ARGUMENT_PACK_SELECT_ARG (r);
12037 if (DECL_TEMPLATE_PARM_P (t))
12038 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12039 /* There is no need to substitute into namespace-scope
12041 if (DECL_NAMESPACE_SCOPE_P (t))
12043 /* If ARGS is NULL, then T is known to be non-dependent. */
12044 if (args == NULL_TREE)
12045 return integral_constant_value (t);
12047 /* Unfortunately, we cannot just call lookup_name here.
12050 template <int I> int f() {
12052 struct S { void g() { E e = a; } };
12055 When we instantiate f<7>::S::g(), say, lookup_name is not
12056 clever enough to find f<7>::a. */
12058 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12059 /*entering_scope=*/0);
12061 for (v = TYPE_VALUES (enum_type);
12063 v = TREE_CHAIN (v))
12064 if (TREE_PURPOSE (v) == DECL_NAME (t))
12065 return TREE_VALUE (v);
12067 /* We didn't find the name. That should never happen; if
12068 name-lookup found it during preliminary parsing, we
12069 should find it again here during instantiation. */
12070 gcc_unreachable ();
12075 if (DECL_CONTEXT (t))
12079 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12080 /*entering_scope=*/1);
12081 if (ctx != DECL_CONTEXT (t))
12083 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12086 if (complain & tf_error)
12087 error ("using invalid field %qD", t);
12088 return error_mark_node;
12097 case FUNCTION_DECL:
12098 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12099 || local_variable_p (t))
12100 t = tsubst (t, args, complain, in_decl);
12104 case NAMESPACE_DECL:
12108 /* An OVERLOAD will always be a non-dependent overload set; an
12109 overload set from function scope will just be represented with an
12110 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12111 gcc_assert (!uses_template_parms (t));
12115 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12117 case TEMPLATE_DECL:
12118 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12119 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12120 args, complain, in_decl);
12121 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12122 return tsubst (t, args, complain, in_decl);
12123 else if (DECL_CLASS_SCOPE_P (t)
12124 && uses_template_parms (DECL_CONTEXT (t)))
12126 /* Template template argument like the following example need
12129 template <template <class> class TT> struct C {};
12130 template <class T> struct D {
12131 template <class U> struct E {};
12136 We are processing the template argument `E' in #1 for
12137 the template instantiation #2. Originally, `E' is a
12138 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12139 have to substitute this with one having context `D<int>'. */
12141 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12142 return lookup_field (context, DECL_NAME(t), 0, false);
12145 /* Ordinary template template argument. */
12149 case REINTERPRET_CAST_EXPR:
12150 case CONST_CAST_EXPR:
12151 case STATIC_CAST_EXPR:
12152 case DYNAMIC_CAST_EXPR:
12153 case IMPLICIT_CONV_EXPR:
12157 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12158 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12161 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12167 ++cp_unevaluated_operand;
12168 ++c_inhibit_evaluation_warnings;
12169 /* We only want to compute the number of arguments. */
12170 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12171 complain, in_decl);
12172 --cp_unevaluated_operand;
12173 --c_inhibit_evaluation_warnings;
12175 if (TREE_CODE (expanded) == TREE_VEC)
12176 len = TREE_VEC_LENGTH (expanded);
12178 if (expanded == error_mark_node)
12179 return error_mark_node;
12180 else if (PACK_EXPANSION_P (expanded)
12181 || (TREE_CODE (expanded) == TREE_VEC
12183 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12185 if (TREE_CODE (expanded) == TREE_VEC)
12186 expanded = TREE_VEC_ELT (expanded, len - 1);
12188 if (TYPE_P (expanded))
12189 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12190 complain & tf_error);
12192 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12193 complain & tf_error);
12196 return build_int_cst (size_type_node, len);
12202 case TRUTH_NOT_EXPR:
12205 case UNARY_PLUS_EXPR: /* Unary + */
12207 case AT_ENCODE_EXPR:
12211 case REALPART_EXPR:
12212 case IMAGPART_EXPR:
12214 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12215 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12217 case COMPONENT_REF:
12222 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12223 name = TREE_OPERAND (t, 1);
12224 if (TREE_CODE (name) == BIT_NOT_EXPR)
12226 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12227 complain, in_decl);
12228 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12230 else if (TREE_CODE (name) == SCOPE_REF
12231 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12233 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12234 complain, in_decl);
12235 name = TREE_OPERAND (name, 1);
12236 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12237 complain, in_decl);
12238 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12239 name = build_qualified_name (/*type=*/NULL_TREE,
12241 /*template_p=*/false);
12243 else if (BASELINK_P (name))
12244 name = tsubst_baselink (name,
12245 non_reference (TREE_TYPE (object)),
12249 name = tsubst_copy (name, args, complain, in_decl);
12250 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12256 case TRUNC_DIV_EXPR:
12257 case CEIL_DIV_EXPR:
12258 case FLOOR_DIV_EXPR:
12259 case ROUND_DIV_EXPR:
12260 case EXACT_DIV_EXPR:
12264 case TRUNC_MOD_EXPR:
12265 case FLOOR_MOD_EXPR:
12266 case TRUTH_ANDIF_EXPR:
12267 case TRUTH_ORIF_EXPR:
12268 case TRUTH_AND_EXPR:
12269 case TRUTH_OR_EXPR:
12282 case COMPOUND_EXPR:
12285 case PREDECREMENT_EXPR:
12286 case PREINCREMENT_EXPR:
12287 case POSTDECREMENT_EXPR:
12288 case POSTINCREMENT_EXPR:
12290 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12291 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12294 return build_qualified_name (/*type=*/NULL_TREE,
12295 tsubst_copy (TREE_OPERAND (t, 0),
12296 args, complain, in_decl),
12297 tsubst_copy (TREE_OPERAND (t, 1),
12298 args, complain, in_decl),
12299 QUALIFIED_NAME_IS_TEMPLATE (t));
12304 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12305 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12306 NULL_TREE, NULL_TREE);
12310 int n = VL_EXP_OPERAND_LENGTH (t);
12311 tree result = build_vl_exp (CALL_EXPR, n);
12313 for (i = 0; i < n; i++)
12314 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12315 complain, in_decl);
12321 case PSEUDO_DTOR_EXPR:
12324 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12325 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12326 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12327 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12334 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12335 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12336 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12337 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12344 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12345 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12346 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12347 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12351 case TEMPLATE_ID_EXPR:
12353 /* Substituted template arguments */
12354 tree fn = TREE_OPERAND (t, 0);
12355 tree targs = TREE_OPERAND (t, 1);
12357 fn = tsubst_copy (fn, args, complain, in_decl);
12359 targs = tsubst_template_args (targs, args, complain, in_decl);
12361 return lookup_template_function (fn, targs);
12366 tree purpose, value, chain;
12368 if (t == void_list_node)
12371 purpose = TREE_PURPOSE (t);
12373 purpose = tsubst_copy (purpose, args, complain, in_decl);
12374 value = TREE_VALUE (t);
12376 value = tsubst_copy (value, args, complain, in_decl);
12377 chain = TREE_CHAIN (t);
12378 if (chain && chain != void_type_node)
12379 chain = tsubst_copy (chain, args, complain, in_decl);
12380 if (purpose == TREE_PURPOSE (t)
12381 && value == TREE_VALUE (t)
12382 && chain == TREE_CHAIN (t))
12384 return tree_cons (purpose, value, chain);
12389 case ENUMERAL_TYPE:
12391 case TEMPLATE_TYPE_PARM:
12392 case TEMPLATE_TEMPLATE_PARM:
12393 case BOUND_TEMPLATE_TEMPLATE_PARM:
12394 case TEMPLATE_PARM_INDEX:
12396 case REFERENCE_TYPE:
12398 case FUNCTION_TYPE:
12401 case TYPENAME_TYPE:
12402 case UNBOUND_CLASS_TEMPLATE:
12404 case DECLTYPE_TYPE:
12406 return tsubst (t, args, complain, in_decl);
12408 case IDENTIFIER_NODE:
12409 if (IDENTIFIER_TYPENAME_P (t))
12411 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12412 return mangle_conv_op_name_for_type (new_type);
12418 /* This is handled by tsubst_copy_and_build. */
12419 gcc_unreachable ();
12422 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12424 tsubst (TREE_TYPE (t), args, complain, in_decl));
12426 case CLEANUP_POINT_EXPR:
12427 /* We shouldn't have built any of these during initial template
12428 generation. Instead, they should be built during instantiation
12429 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12430 gcc_unreachable ();
12434 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12435 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12436 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12437 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12438 mark_used (TREE_OPERAND (r, 1));
12441 case EXPR_PACK_EXPANSION:
12442 error ("invalid use of pack expansion expression");
12443 return error_mark_node;
12445 case NONTYPE_ARGUMENT_PACK:
12446 error ("use %<...%> to expand argument pack");
12447 return error_mark_node;
12454 /* Instantiate any typedefs in the type. */
12455 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12456 r = fold_convert (type, t);
12457 gcc_assert (TREE_CODE (r) == code);
12462 /* These can sometimes show up in a partial instantiation, but never
12463 involve template parms. */
12464 gcc_assert (!uses_template_parms (t));
12468 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12469 gcc_checking_assert (false);
12474 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12477 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12480 tree new_clauses = NULL, nc, oc;
12482 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12484 nc = copy_node (oc);
12485 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12488 switch (OMP_CLAUSE_CODE (nc))
12490 case OMP_CLAUSE_LASTPRIVATE:
12491 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12493 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12494 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12495 in_decl, /*integral_constant_expression_p=*/false);
12496 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12497 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12500 case OMP_CLAUSE_PRIVATE:
12501 case OMP_CLAUSE_SHARED:
12502 case OMP_CLAUSE_FIRSTPRIVATE:
12503 case OMP_CLAUSE_REDUCTION:
12504 case OMP_CLAUSE_COPYIN:
12505 case OMP_CLAUSE_COPYPRIVATE:
12506 case OMP_CLAUSE_IF:
12507 case OMP_CLAUSE_NUM_THREADS:
12508 case OMP_CLAUSE_SCHEDULE:
12509 case OMP_CLAUSE_COLLAPSE:
12510 case OMP_CLAUSE_FINAL:
12511 OMP_CLAUSE_OPERAND (nc, 0)
12512 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12513 in_decl, /*integral_constant_expression_p=*/false);
12515 case OMP_CLAUSE_NOWAIT:
12516 case OMP_CLAUSE_ORDERED:
12517 case OMP_CLAUSE_DEFAULT:
12518 case OMP_CLAUSE_UNTIED:
12519 case OMP_CLAUSE_MERGEABLE:
12522 gcc_unreachable ();
12526 return finish_omp_clauses (nreverse (new_clauses));
12529 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12532 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12535 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12537 tree purpose, value, chain;
12542 if (TREE_CODE (t) != TREE_LIST)
12543 return tsubst_copy_and_build (t, args, complain, in_decl,
12544 /*function_p=*/false,
12545 /*integral_constant_expression_p=*/false);
12547 if (t == void_list_node)
12550 purpose = TREE_PURPOSE (t);
12552 purpose = RECUR (purpose);
12553 value = TREE_VALUE (t);
12554 if (value && TREE_CODE (value) != LABEL_DECL)
12555 value = RECUR (value);
12556 chain = TREE_CHAIN (t);
12557 if (chain && chain != void_type_node)
12558 chain = RECUR (chain);
12559 return tree_cons (purpose, value, chain);
12563 /* Substitute one OMP_FOR iterator. */
12566 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12567 tree condv, tree incrv, tree *clauses,
12568 tree args, tsubst_flags_t complain, tree in_decl,
12569 bool integral_constant_expression_p)
12571 #define RECUR(NODE) \
12572 tsubst_expr ((NODE), args, complain, in_decl, \
12573 integral_constant_expression_p)
12574 tree decl, init, cond, incr, auto_node;
12576 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12577 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12578 decl = RECUR (TREE_OPERAND (init, 0));
12579 init = TREE_OPERAND (init, 1);
12580 auto_node = type_uses_auto (TREE_TYPE (decl));
12581 if (auto_node && init)
12583 tree init_expr = init;
12584 if (TREE_CODE (init_expr) == DECL_EXPR)
12585 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12586 init_expr = RECUR (init_expr);
12588 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12590 gcc_assert (!type_dependent_expression_p (decl));
12592 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12594 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12595 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12596 if (TREE_CODE (incr) == MODIFY_EXPR)
12597 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12598 RECUR (TREE_OPERAND (incr, 1)),
12601 incr = RECUR (incr);
12602 TREE_VEC_ELT (declv, i) = decl;
12603 TREE_VEC_ELT (initv, i) = init;
12604 TREE_VEC_ELT (condv, i) = cond;
12605 TREE_VEC_ELT (incrv, i) = incr;
12609 if (init && TREE_CODE (init) != DECL_EXPR)
12612 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12614 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12615 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12616 && OMP_CLAUSE_DECL (c) == decl)
12618 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12619 && OMP_CLAUSE_DECL (c) == decl)
12620 error ("iteration variable %qD should not be firstprivate", decl);
12621 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12622 && OMP_CLAUSE_DECL (c) == decl)
12623 error ("iteration variable %qD should not be reduction", decl);
12627 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12628 OMP_CLAUSE_DECL (c) = decl;
12629 c = finish_omp_clauses (c);
12632 OMP_CLAUSE_CHAIN (c) = *clauses;
12637 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12638 if (COMPARISON_CLASS_P (cond))
12639 cond = build2 (TREE_CODE (cond), boolean_type_node,
12640 RECUR (TREE_OPERAND (cond, 0)),
12641 RECUR (TREE_OPERAND (cond, 1)));
12643 cond = RECUR (cond);
12644 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12645 switch (TREE_CODE (incr))
12647 case PREINCREMENT_EXPR:
12648 case PREDECREMENT_EXPR:
12649 case POSTINCREMENT_EXPR:
12650 case POSTDECREMENT_EXPR:
12651 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12652 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12655 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12656 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12658 tree rhs = TREE_OPERAND (incr, 1);
12659 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12660 RECUR (TREE_OPERAND (incr, 0)),
12661 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12662 RECUR (TREE_OPERAND (rhs, 0)),
12663 RECUR (TREE_OPERAND (rhs, 1))));
12666 incr = RECUR (incr);
12669 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12670 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12672 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12673 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12674 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12675 TREE_TYPE (decl), lhs,
12676 RECUR (TREE_OPERAND (incr, 2))));
12678 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12679 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12680 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12682 tree rhs = TREE_OPERAND (incr, 2);
12683 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12684 RECUR (TREE_OPERAND (incr, 0)),
12685 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12686 RECUR (TREE_OPERAND (rhs, 0)),
12687 RECUR (TREE_OPERAND (rhs, 1))));
12690 incr = RECUR (incr);
12693 incr = RECUR (incr);
12697 TREE_VEC_ELT (declv, i) = decl;
12698 TREE_VEC_ELT (initv, i) = init;
12699 TREE_VEC_ELT (condv, i) = cond;
12700 TREE_VEC_ELT (incrv, i) = incr;
12704 /* Like tsubst_copy for expressions, etc. but also does semantic
12708 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12709 bool integral_constant_expression_p)
12711 #define RECUR(NODE) \
12712 tsubst_expr ((NODE), args, complain, in_decl, \
12713 integral_constant_expression_p)
12717 if (t == NULL_TREE || t == error_mark_node)
12720 if (EXPR_HAS_LOCATION (t))
12721 input_location = EXPR_LOCATION (t);
12722 if (STATEMENT_CODE_P (TREE_CODE (t)))
12723 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12725 switch (TREE_CODE (t))
12727 case STATEMENT_LIST:
12729 tree_stmt_iterator i;
12730 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12731 RECUR (tsi_stmt (i));
12735 case CTOR_INITIALIZER:
12736 finish_mem_initializers (tsubst_initializer_list
12737 (TREE_OPERAND (t, 0), args));
12741 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12745 tmp = RECUR (EXPR_STMT_EXPR (t));
12746 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12747 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12749 finish_expr_stmt (tmp);
12753 do_using_directive (USING_STMT_NAMESPACE (t));
12758 tree decl, pattern_decl;
12761 pattern_decl = decl = DECL_EXPR_DECL (t);
12762 if (TREE_CODE (decl) == LABEL_DECL)
12763 finish_label_decl (DECL_NAME (decl));
12764 else if (TREE_CODE (decl) == USING_DECL)
12766 tree scope = USING_DECL_SCOPE (decl);
12767 tree name = DECL_NAME (decl);
12770 scope = tsubst (scope, args, complain, in_decl);
12771 decl = lookup_qualified_name (scope, name,
12772 /*is_type_p=*/false,
12773 /*complain=*/false);
12774 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12775 qualified_name_lookup_error (scope, name, decl, input_location);
12777 do_local_using_decl (decl, scope, name);
12781 init = DECL_INITIAL (decl);
12782 decl = tsubst (decl, args, complain, in_decl);
12783 if (decl != error_mark_node)
12785 /* By marking the declaration as instantiated, we avoid
12786 trying to instantiate it. Since instantiate_decl can't
12787 handle local variables, and since we've already done
12788 all that needs to be done, that's the right thing to
12790 if (TREE_CODE (decl) == VAR_DECL)
12791 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12792 if (TREE_CODE (decl) == VAR_DECL
12793 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12794 /* Anonymous aggregates are a special case. */
12795 finish_anon_union (decl);
12798 int const_init = false;
12799 maybe_push_decl (decl);
12800 if (TREE_CODE (decl) == VAR_DECL
12801 && DECL_PRETTY_FUNCTION_P (decl))
12803 /* For __PRETTY_FUNCTION__ we have to adjust the
12805 const char *const name
12806 = cxx_printable_name (current_function_decl, 2);
12807 init = cp_fname_init (name, &TREE_TYPE (decl));
12811 tree t = RECUR (init);
12815 /* If we had an initializer but it
12816 instantiated to nothing,
12817 value-initialize the object. This will
12818 only occur when the initializer was a
12819 pack expansion where the parameter packs
12820 used in that expansion were of length
12822 init = build_value_init (TREE_TYPE (decl),
12824 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12825 init = get_target_expr_sfinae (init, complain);
12831 if (TREE_CODE (decl) == VAR_DECL)
12832 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12834 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12839 /* A DECL_EXPR can also be used as an expression, in the condition
12840 clause of an if/for/while construct. */
12845 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12846 RECUR (FOR_INIT_STMT (t));
12847 finish_for_init_stmt (stmt);
12848 tmp = RECUR (FOR_COND (t));
12849 finish_for_cond (tmp, stmt);
12850 tmp = RECUR (FOR_EXPR (t));
12851 finish_for_expr (tmp, stmt);
12852 RECUR (FOR_BODY (t));
12853 finish_for_stmt (stmt);
12856 case RANGE_FOR_STMT:
12859 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12860 decl = RANGE_FOR_DECL (t);
12861 decl = tsubst (decl, args, complain, in_decl);
12862 maybe_push_decl (decl);
12863 expr = RECUR (RANGE_FOR_EXPR (t));
12864 stmt = cp_convert_range_for (stmt, decl, expr);
12865 RECUR (RANGE_FOR_BODY (t));
12866 finish_for_stmt (stmt);
12871 stmt = begin_while_stmt ();
12872 tmp = RECUR (WHILE_COND (t));
12873 finish_while_stmt_cond (tmp, stmt);
12874 RECUR (WHILE_BODY (t));
12875 finish_while_stmt (stmt);
12879 stmt = begin_do_stmt ();
12880 RECUR (DO_BODY (t));
12881 finish_do_body (stmt);
12882 tmp = RECUR (DO_COND (t));
12883 finish_do_stmt (tmp, stmt);
12887 stmt = begin_if_stmt ();
12888 tmp = RECUR (IF_COND (t));
12889 finish_if_stmt_cond (tmp, stmt);
12890 RECUR (THEN_CLAUSE (t));
12891 finish_then_clause (stmt);
12893 if (ELSE_CLAUSE (t))
12895 begin_else_clause (stmt);
12896 RECUR (ELSE_CLAUSE (t));
12897 finish_else_clause (stmt);
12900 finish_if_stmt (stmt);
12904 if (BIND_EXPR_BODY_BLOCK (t))
12905 stmt = begin_function_body ();
12907 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12908 ? BCS_TRY_BLOCK : 0);
12910 RECUR (BIND_EXPR_BODY (t));
12912 if (BIND_EXPR_BODY_BLOCK (t))
12913 finish_function_body (stmt);
12915 finish_compound_stmt (stmt);
12919 finish_break_stmt ();
12922 case CONTINUE_STMT:
12923 finish_continue_stmt ();
12927 stmt = begin_switch_stmt ();
12928 tmp = RECUR (SWITCH_STMT_COND (t));
12929 finish_switch_cond (tmp, stmt);
12930 RECUR (SWITCH_STMT_BODY (t));
12931 finish_switch_stmt (stmt);
12934 case CASE_LABEL_EXPR:
12935 finish_case_label (EXPR_LOCATION (t),
12936 RECUR (CASE_LOW (t)),
12937 RECUR (CASE_HIGH (t)));
12942 tree decl = LABEL_EXPR_LABEL (t);
12945 label = finish_label_stmt (DECL_NAME (decl));
12946 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12947 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12952 tmp = GOTO_DESTINATION (t);
12953 if (TREE_CODE (tmp) != LABEL_DECL)
12954 /* Computed goto's must be tsubst'd into. On the other hand,
12955 non-computed gotos must not be; the identifier in question
12956 will have no binding. */
12959 tmp = DECL_NAME (tmp);
12960 finish_goto_stmt (tmp);
12964 tmp = finish_asm_stmt
12965 (ASM_VOLATILE_P (t),
12966 RECUR (ASM_STRING (t)),
12967 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12968 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12969 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12970 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12972 tree asm_expr = tmp;
12973 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12974 asm_expr = TREE_OPERAND (asm_expr, 0);
12975 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12982 stmt = begin_try_block ();
12983 RECUR (TRY_STMTS (t));
12984 finish_cleanup_try_block (stmt);
12985 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12989 tree compound_stmt = NULL_TREE;
12991 if (FN_TRY_BLOCK_P (t))
12992 stmt = begin_function_try_block (&compound_stmt);
12994 stmt = begin_try_block ();
12996 RECUR (TRY_STMTS (t));
12998 if (FN_TRY_BLOCK_P (t))
12999 finish_function_try_block (stmt);
13001 finish_try_block (stmt);
13003 RECUR (TRY_HANDLERS (t));
13004 if (FN_TRY_BLOCK_P (t))
13005 finish_function_handler_sequence (stmt, compound_stmt);
13007 finish_handler_sequence (stmt);
13013 tree decl = HANDLER_PARMS (t);
13017 decl = tsubst (decl, args, complain, in_decl);
13018 /* Prevent instantiate_decl from trying to instantiate
13019 this variable. We've already done all that needs to be
13021 if (decl != error_mark_node)
13022 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13024 stmt = begin_handler ();
13025 finish_handler_parms (decl, stmt);
13026 RECUR (HANDLER_BODY (t));
13027 finish_handler (stmt);
13032 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13035 case STATIC_ASSERT:
13038 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13041 /*integral_constant_expression_p=*/true);
13042 finish_static_assert (condition,
13043 STATIC_ASSERT_MESSAGE (t),
13044 STATIC_ASSERT_SOURCE_LOCATION (t),
13045 /*member_p=*/false);
13050 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13051 args, complain, in_decl);
13052 stmt = begin_omp_parallel ();
13053 RECUR (OMP_PARALLEL_BODY (t));
13054 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13055 = OMP_PARALLEL_COMBINED (t);
13059 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13060 args, complain, in_decl);
13061 stmt = begin_omp_task ();
13062 RECUR (OMP_TASK_BODY (t));
13063 finish_omp_task (tmp, stmt);
13068 tree clauses, body, pre_body;
13069 tree declv, initv, condv, incrv;
13072 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13073 args, complain, in_decl);
13074 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13075 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13076 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13077 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13079 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13080 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13081 &clauses, args, complain, in_decl,
13082 integral_constant_expression_p);
13084 stmt = begin_omp_structured_block ();
13086 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13087 if (TREE_VEC_ELT (initv, i) == NULL
13088 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13089 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13090 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13092 tree init = RECUR (TREE_VEC_ELT (initv, i));
13093 gcc_assert (init == TREE_VEC_ELT (declv, i));
13094 TREE_VEC_ELT (initv, i) = NULL_TREE;
13098 tree decl_expr = TREE_VEC_ELT (initv, i);
13099 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13100 gcc_assert (init != NULL);
13101 TREE_VEC_ELT (initv, i) = RECUR (init);
13102 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13104 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13107 pre_body = push_stmt_list ();
13108 RECUR (OMP_FOR_PRE_BODY (t));
13109 pre_body = pop_stmt_list (pre_body);
13111 body = push_stmt_list ();
13112 RECUR (OMP_FOR_BODY (t));
13113 body = pop_stmt_list (body);
13115 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13116 body, pre_body, clauses);
13118 add_stmt (finish_omp_structured_block (stmt));
13124 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13125 stmt = push_stmt_list ();
13126 RECUR (OMP_BODY (t));
13127 stmt = pop_stmt_list (stmt);
13130 OMP_BODY (t) = stmt;
13131 OMP_CLAUSES (t) = tmp;
13139 stmt = push_stmt_list ();
13140 RECUR (OMP_BODY (t));
13141 stmt = pop_stmt_list (stmt);
13144 OMP_BODY (t) = stmt;
13149 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13150 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13152 tree op1 = TREE_OPERAND (t, 1);
13153 tree rhs1 = NULL_TREE;
13155 if (TREE_CODE (op1) == COMPOUND_EXPR)
13157 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13158 op1 = TREE_OPERAND (op1, 1);
13160 lhs = RECUR (TREE_OPERAND (op1, 0));
13161 rhs = RECUR (TREE_OPERAND (op1, 1));
13162 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13163 NULL_TREE, NULL_TREE, rhs1);
13167 tree op1 = TREE_OPERAND (t, 1);
13168 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13169 tree rhs1 = NULL_TREE;
13170 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13171 enum tree_code opcode = NOP_EXPR;
13172 if (code == OMP_ATOMIC_READ)
13174 v = RECUR (TREE_OPERAND (op1, 0));
13175 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13177 else if (code == OMP_ATOMIC_CAPTURE_OLD
13178 || code == OMP_ATOMIC_CAPTURE_NEW)
13180 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13181 v = RECUR (TREE_OPERAND (op1, 0));
13182 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13183 if (TREE_CODE (op11) == COMPOUND_EXPR)
13185 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13186 op11 = TREE_OPERAND (op11, 1);
13188 lhs = RECUR (TREE_OPERAND (op11, 0));
13189 rhs = RECUR (TREE_OPERAND (op11, 1));
13190 opcode = TREE_CODE (op11);
13195 lhs = RECUR (TREE_OPERAND (op1, 0));
13196 rhs = RECUR (TREE_OPERAND (op1, 1));
13198 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13202 case TRANSACTION_EXPR:
13205 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13206 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13208 if (TRANSACTION_EXPR_IS_STMT (t))
13210 stmt = begin_transaction_stmt (input_location, NULL, flags);
13211 RECUR (TRANSACTION_EXPR_BODY (t));
13212 finish_transaction_stmt (stmt, NULL, flags);
13216 stmt = build_transaction_expr (EXPR_LOCATION (t),
13217 RECUR (TRANSACTION_EXPR_BODY (t)),
13224 case EXPR_PACK_EXPANSION:
13225 error ("invalid use of pack expansion expression");
13226 return error_mark_node;
13228 case NONTYPE_ARGUMENT_PACK:
13229 error ("use %<...%> to expand argument pack");
13230 return error_mark_node;
13233 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13235 return tsubst_copy_and_build (t, args, complain, in_decl,
13236 /*function_p=*/false,
13237 integral_constant_expression_p);
13244 /* T is a postfix-expression that is not being used in a function
13245 call. Return the substituted version of T. */
13248 tsubst_non_call_postfix_expression (tree t, tree args,
13249 tsubst_flags_t complain,
13252 if (TREE_CODE (t) == SCOPE_REF)
13253 t = tsubst_qualified_id (t, args, complain, in_decl,
13254 /*done=*/false, /*address_p=*/false);
13256 t = tsubst_copy_and_build (t, args, complain, in_decl,
13257 /*function_p=*/false,
13258 /*integral_constant_expression_p=*/false);
13263 /* Like tsubst but deals with expressions and performs semantic
13264 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13267 tsubst_copy_and_build (tree t,
13269 tsubst_flags_t complain,
13272 bool integral_constant_expression_p)
13274 #define RECUR(NODE) \
13275 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13276 /*function_p=*/false, \
13277 integral_constant_expression_p)
13281 if (t == NULL_TREE || t == error_mark_node)
13284 switch (TREE_CODE (t))
13288 /* Fall through. */
13289 case IDENTIFIER_NODE:
13293 bool non_integral_constant_expression_p;
13294 const char *error_msg;
13296 if (IDENTIFIER_TYPENAME_P (t))
13298 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13299 t = mangle_conv_op_name_for_type (new_type);
13302 /* Look up the name. */
13303 decl = lookup_name (t);
13305 /* By convention, expressions use ERROR_MARK_NODE to indicate
13306 failure, not NULL_TREE. */
13307 if (decl == NULL_TREE)
13308 decl = error_mark_node;
13310 decl = finish_id_expression (t, decl, NULL_TREE,
13312 integral_constant_expression_p,
13313 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13314 &non_integral_constant_expression_p,
13315 /*template_p=*/false,
13317 /*address_p=*/false,
13318 /*template_arg_p=*/false,
13323 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13325 if (complain & tf_error)
13326 unqualified_name_lookup_error (decl);
13327 decl = error_mark_node;
13332 case TEMPLATE_ID_EXPR:
13335 tree templ = RECUR (TREE_OPERAND (t, 0));
13336 tree targs = TREE_OPERAND (t, 1);
13339 targs = tsubst_template_args (targs, args, complain, in_decl);
13341 if (TREE_CODE (templ) == COMPONENT_REF)
13343 object = TREE_OPERAND (templ, 0);
13344 templ = TREE_OPERAND (templ, 1);
13347 object = NULL_TREE;
13348 templ = lookup_template_function (templ, targs);
13351 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13352 object, templ, NULL_TREE);
13354 return baselink_for_fns (templ);
13359 tree r = RECUR (TREE_OPERAND (t, 0));
13361 if (REFERENCE_REF_P (t))
13363 /* A type conversion to reference type will be enclosed in
13364 such an indirect ref, but the substitution of the cast
13365 will have also added such an indirect ref. */
13366 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13367 r = convert_from_reference (r);
13370 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13376 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13377 RECUR (TREE_OPERAND (t, 0)));
13379 case IMPLICIT_CONV_EXPR:
13381 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13382 tree expr = RECUR (TREE_OPERAND (t, 0));
13383 int flags = LOOKUP_IMPLICIT;
13384 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13385 flags = LOOKUP_NORMAL;
13386 return perform_implicit_conversion_flags (type, expr, complain,
13393 tsubst (TREE_TYPE (t), args, complain, in_decl),
13394 RECUR (TREE_OPERAND (t, 0)));
13397 case REINTERPRET_CAST_EXPR:
13398 case CONST_CAST_EXPR:
13399 case DYNAMIC_CAST_EXPR:
13400 case STATIC_CAST_EXPR:
13405 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13406 if (integral_constant_expression_p
13407 && !cast_valid_in_integral_constant_expression_p (type))
13409 if (complain & tf_error)
13410 error ("a cast to a type other than an integral or "
13411 "enumeration type cannot appear in a constant-expression");
13412 return error_mark_node;
13415 op = RECUR (TREE_OPERAND (t, 0));
13417 switch (TREE_CODE (t))
13420 return build_functional_cast (type, op, complain);
13421 case REINTERPRET_CAST_EXPR:
13422 return build_reinterpret_cast (type, op, complain);
13423 case CONST_CAST_EXPR:
13424 return build_const_cast (type, op, complain);
13425 case DYNAMIC_CAST_EXPR:
13426 return build_dynamic_cast (type, op, complain);
13427 case STATIC_CAST_EXPR:
13428 return build_static_cast (type, op, complain);
13430 gcc_unreachable ();
13434 case POSTDECREMENT_EXPR:
13435 case POSTINCREMENT_EXPR:
13436 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13437 args, complain, in_decl);
13438 return build_x_unary_op (TREE_CODE (t), op1, complain);
13440 case PREDECREMENT_EXPR:
13441 case PREINCREMENT_EXPR:
13445 case TRUTH_NOT_EXPR:
13446 case UNARY_PLUS_EXPR: /* Unary + */
13447 case REALPART_EXPR:
13448 case IMAGPART_EXPR:
13449 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13452 case FIX_TRUNC_EXPR:
13453 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13457 op1 = TREE_OPERAND (t, 0);
13458 if (TREE_CODE (op1) == LABEL_DECL)
13459 return finish_label_address_expr (DECL_NAME (op1),
13460 EXPR_LOCATION (op1));
13461 if (TREE_CODE (op1) == SCOPE_REF)
13462 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13463 /*done=*/true, /*address_p=*/true);
13465 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13467 return build_x_unary_op (ADDR_EXPR, op1, complain);
13472 case TRUNC_DIV_EXPR:
13473 case CEIL_DIV_EXPR:
13474 case FLOOR_DIV_EXPR:
13475 case ROUND_DIV_EXPR:
13476 case EXACT_DIV_EXPR:
13480 case TRUNC_MOD_EXPR:
13481 case FLOOR_MOD_EXPR:
13482 case TRUTH_ANDIF_EXPR:
13483 case TRUTH_ORIF_EXPR:
13484 case TRUTH_AND_EXPR:
13485 case TRUTH_OR_EXPR:
13500 return build_x_binary_op
13502 RECUR (TREE_OPERAND (t, 0)),
13503 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13505 : TREE_CODE (TREE_OPERAND (t, 0))),
13506 RECUR (TREE_OPERAND (t, 1)),
13507 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13509 : TREE_CODE (TREE_OPERAND (t, 1))),
13514 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13515 /*address_p=*/false);
13517 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13518 args, complain, in_decl);
13519 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13522 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13523 return tsubst_copy (t, args, complain, in_decl);
13527 op1 = TREE_OPERAND (t, 0);
13530 /* When there are no ARGS, we are trying to evaluate a
13531 non-dependent expression from the parser. Trying to do
13532 the substitutions may not work. */
13534 op1 = TREE_TYPE (op1);
13538 ++cp_unevaluated_operand;
13539 ++c_inhibit_evaluation_warnings;
13540 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13541 /*function_p=*/false,
13542 /*integral_constant_expression_p=*/false);
13543 --cp_unevaluated_operand;
13544 --c_inhibit_evaluation_warnings;
13547 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13548 complain & tf_error);
13550 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13551 complain & tf_error);
13553 case AT_ENCODE_EXPR:
13555 op1 = TREE_OPERAND (t, 0);
13556 ++cp_unevaluated_operand;
13557 ++c_inhibit_evaluation_warnings;
13558 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13559 /*function_p=*/false,
13560 /*integral_constant_expression_p=*/false);
13561 --cp_unevaluated_operand;
13562 --c_inhibit_evaluation_warnings;
13563 return objc_build_encode_expr (op1);
13566 case NOEXCEPT_EXPR:
13567 op1 = TREE_OPERAND (t, 0);
13568 ++cp_unevaluated_operand;
13569 ++c_inhibit_evaluation_warnings;
13570 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13571 /*function_p=*/false,
13572 /*integral_constant_expression_p=*/false);
13573 --cp_unevaluated_operand;
13574 --c_inhibit_evaluation_warnings;
13575 return finish_noexcept_expr (op1, complain);
13579 tree r = build_x_modify_expr
13580 (RECUR (TREE_OPERAND (t, 0)),
13581 TREE_CODE (TREE_OPERAND (t, 1)),
13582 RECUR (TREE_OPERAND (t, 2)),
13584 /* TREE_NO_WARNING must be set if either the expression was
13585 parenthesized or it uses an operator such as >>= rather
13586 than plain assignment. In the former case, it was already
13587 set and must be copied. In the latter case,
13588 build_x_modify_expr sets it and it must not be reset
13590 if (TREE_NO_WARNING (t))
13591 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13596 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13597 args, complain, in_decl);
13598 /* Remember that there was a reference to this entity. */
13601 return build_x_arrow (op1);
13605 tree placement = RECUR (TREE_OPERAND (t, 0));
13606 tree init = RECUR (TREE_OPERAND (t, 3));
13607 VEC(tree,gc) *placement_vec;
13608 VEC(tree,gc) *init_vec;
13611 if (placement == NULL_TREE)
13612 placement_vec = NULL;
13615 placement_vec = make_tree_vector ();
13616 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13617 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13620 /* If there was an initializer in the original tree, but it
13621 instantiated to an empty list, then we should pass a
13622 non-NULL empty vector to tell build_new that it was an
13623 empty initializer() rather than no initializer. This can
13624 only happen when the initializer is a pack expansion whose
13625 parameter packs are of length zero. */
13626 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13630 init_vec = make_tree_vector ();
13631 if (init == void_zero_node)
13632 gcc_assert (init_vec != NULL);
13635 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13636 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13640 ret = build_new (&placement_vec,
13641 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13642 RECUR (TREE_OPERAND (t, 2)),
13644 NEW_EXPR_USE_GLOBAL (t),
13647 if (placement_vec != NULL)
13648 release_tree_vector (placement_vec);
13649 if (init_vec != NULL)
13650 release_tree_vector (init_vec);
13656 return delete_sanity
13657 (RECUR (TREE_OPERAND (t, 0)),
13658 RECUR (TREE_OPERAND (t, 1)),
13659 DELETE_EXPR_USE_VEC (t),
13660 DELETE_EXPR_USE_GLOBAL (t),
13663 case COMPOUND_EXPR:
13664 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13665 RECUR (TREE_OPERAND (t, 1)),
13671 VEC(tree,gc) *call_args;
13672 unsigned int nargs, i;
13677 function = CALL_EXPR_FN (t);
13678 /* When we parsed the expression, we determined whether or
13679 not Koenig lookup should be performed. */
13680 koenig_p = KOENIG_LOOKUP_P (t);
13681 if (TREE_CODE (function) == SCOPE_REF)
13683 qualified_p = true;
13684 function = tsubst_qualified_id (function, args, complain, in_decl,
13686 /*address_p=*/false);
13688 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13690 /* Do nothing; calling tsubst_copy_and_build on an identifier
13691 would incorrectly perform unqualified lookup again.
13693 Note that we can also have an IDENTIFIER_NODE if the earlier
13694 unqualified lookup found a member function; in that case
13695 koenig_p will be false and we do want to do the lookup
13696 again to find the instantiated member function.
13698 FIXME but doing that causes c++/15272, so we need to stop
13699 using IDENTIFIER_NODE in that situation. */
13700 qualified_p = false;
13704 if (TREE_CODE (function) == COMPONENT_REF)
13706 tree op = TREE_OPERAND (function, 1);
13708 qualified_p = (TREE_CODE (op) == SCOPE_REF
13709 || (BASELINK_P (op)
13710 && BASELINK_QUALIFIED_P (op)));
13713 qualified_p = false;
13715 function = tsubst_copy_and_build (function, args, complain,
13718 integral_constant_expression_p);
13720 if (BASELINK_P (function))
13721 qualified_p = true;
13724 nargs = call_expr_nargs (t);
13725 call_args = make_tree_vector ();
13726 for (i = 0; i < nargs; ++i)
13728 tree arg = CALL_EXPR_ARG (t, i);
13730 if (!PACK_EXPANSION_P (arg))
13731 VEC_safe_push (tree, gc, call_args,
13732 RECUR (CALL_EXPR_ARG (t, i)));
13735 /* Expand the pack expansion and push each entry onto
13737 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13738 if (TREE_CODE (arg) == TREE_VEC)
13740 unsigned int len, j;
13742 len = TREE_VEC_LENGTH (arg);
13743 for (j = 0; j < len; ++j)
13745 tree value = TREE_VEC_ELT (arg, j);
13746 if (value != NULL_TREE)
13747 value = convert_from_reference (value);
13748 VEC_safe_push (tree, gc, call_args, value);
13753 /* A partial substitution. Add one entry. */
13754 VEC_safe_push (tree, gc, call_args, arg);
13759 /* We do not perform argument-dependent lookup if normal
13760 lookup finds a non-function, in accordance with the
13761 expected resolution of DR 218. */
13763 && ((is_overloaded_fn (function)
13764 /* If lookup found a member function, the Koenig lookup is
13765 not appropriate, even if an unqualified-name was used
13766 to denote the function. */
13767 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13768 || TREE_CODE (function) == IDENTIFIER_NODE)
13769 /* Only do this when substitution turns a dependent call
13770 into a non-dependent call. */
13771 && type_dependent_expression_p_push (t)
13772 && !any_type_dependent_arguments_p (call_args))
13773 function = perform_koenig_lookup (function, call_args, false,
13776 if (TREE_CODE (function) == IDENTIFIER_NODE
13777 && !any_type_dependent_arguments_p (call_args))
13779 if (koenig_p && (complain & tf_warning_or_error))
13781 /* For backwards compatibility and good diagnostics, try
13782 the unqualified lookup again if we aren't in SFINAE
13784 tree unq = (tsubst_copy_and_build
13785 (function, args, complain, in_decl, true,
13786 integral_constant_expression_p));
13787 if (unq == error_mark_node)
13788 return error_mark_node;
13790 if (unq != function)
13793 if (TREE_CODE (fn) == INDIRECT_REF)
13794 fn = TREE_OPERAND (fn, 0);
13795 if (TREE_CODE (fn) == COMPONENT_REF)
13796 fn = TREE_OPERAND (fn, 1);
13797 if (is_overloaded_fn (fn))
13798 fn = get_first_fn (fn);
13799 permerror (EXPR_LOC_OR_HERE (t),
13800 "%qD was not declared in this scope, "
13801 "and no declarations were found by "
13802 "argument-dependent lookup at the point "
13803 "of instantiation", function);
13805 /* Can't say anything more. */;
13806 else if (DECL_CLASS_SCOPE_P (fn))
13808 inform (EXPR_LOC_OR_HERE (t),
13809 "declarations in dependent base %qT are "
13810 "not found by unqualified lookup",
13811 DECL_CLASS_CONTEXT (fn));
13812 if (current_class_ptr)
13813 inform (EXPR_LOC_OR_HERE (t),
13814 "use %<this->%D%> instead", function);
13816 inform (EXPR_LOC_OR_HERE (t),
13817 "use %<%T::%D%> instead",
13818 current_class_name, function);
13821 inform (0, "%q+D declared here, later in the "
13822 "translation unit", fn);
13826 if (TREE_CODE (function) == IDENTIFIER_NODE)
13828 unqualified_name_lookup_error (function);
13829 release_tree_vector (call_args);
13830 return error_mark_node;
13834 /* Remember that there was a reference to this entity. */
13835 if (DECL_P (function))
13836 mark_used (function);
13838 if (TREE_CODE (function) == OFFSET_REF)
13839 ret = build_offset_ref_call_from_tree (function, &call_args);
13840 else if (TREE_CODE (function) == COMPONENT_REF)
13842 tree instance = TREE_OPERAND (function, 0);
13843 tree fn = TREE_OPERAND (function, 1);
13845 if (processing_template_decl
13846 && (type_dependent_expression_p (instance)
13847 || (!BASELINK_P (fn)
13848 && TREE_CODE (fn) != FIELD_DECL)
13849 || type_dependent_expression_p (fn)
13850 || any_type_dependent_arguments_p (call_args)))
13851 ret = build_nt_call_vec (function, call_args);
13852 else if (!BASELINK_P (fn))
13853 ret = finish_call_expr (function, &call_args,
13854 /*disallow_virtual=*/false,
13855 /*koenig_p=*/false,
13858 ret = (build_new_method_call
13860 &call_args, NULL_TREE,
13861 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13866 ret = finish_call_expr (function, &call_args,
13867 /*disallow_virtual=*/qualified_p,
13871 release_tree_vector (call_args);
13877 return build_x_conditional_expr
13878 (RECUR (TREE_OPERAND (t, 0)),
13879 RECUR (TREE_OPERAND (t, 1)),
13880 RECUR (TREE_OPERAND (t, 2)),
13883 case PSEUDO_DTOR_EXPR:
13884 return finish_pseudo_destructor_expr
13885 (RECUR (TREE_OPERAND (t, 0)),
13886 RECUR (TREE_OPERAND (t, 1)),
13887 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13891 tree purpose, value, chain;
13893 if (t == void_list_node)
13896 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13897 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13899 /* We have pack expansions, so expand those and
13900 create a new list out of it. */
13901 tree purposevec = NULL_TREE;
13902 tree valuevec = NULL_TREE;
13906 /* Expand the argument expressions. */
13907 if (TREE_PURPOSE (t))
13908 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13909 complain, in_decl);
13910 if (TREE_VALUE (t))
13911 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13912 complain, in_decl);
13914 /* Build the rest of the list. */
13915 chain = TREE_CHAIN (t);
13916 if (chain && chain != void_type_node)
13917 chain = RECUR (chain);
13919 /* Determine the number of arguments. */
13920 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13922 len = TREE_VEC_LENGTH (purposevec);
13923 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13925 else if (TREE_CODE (valuevec) == TREE_VEC)
13926 len = TREE_VEC_LENGTH (valuevec);
13929 /* Since we only performed a partial substitution into
13930 the argument pack, we only return a single list
13932 if (purposevec == TREE_PURPOSE (t)
13933 && valuevec == TREE_VALUE (t)
13934 && chain == TREE_CHAIN (t))
13937 return tree_cons (purposevec, valuevec, chain);
13940 /* Convert the argument vectors into a TREE_LIST */
13944 /* Grab the Ith values. */
13946 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13949 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13952 /* Build the list (backwards). */
13953 chain = tree_cons (purpose, value, chain);
13959 purpose = TREE_PURPOSE (t);
13961 purpose = RECUR (purpose);
13962 value = TREE_VALUE (t);
13964 value = RECUR (value);
13965 chain = TREE_CHAIN (t);
13966 if (chain && chain != void_type_node)
13967 chain = RECUR (chain);
13968 if (purpose == TREE_PURPOSE (t)
13969 && value == TREE_VALUE (t)
13970 && chain == TREE_CHAIN (t))
13972 return tree_cons (purpose, value, chain);
13975 case COMPONENT_REF:
13981 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13982 args, complain, in_decl);
13983 /* Remember that there was a reference to this entity. */
13984 if (DECL_P (object))
13985 mark_used (object);
13986 object_type = TREE_TYPE (object);
13988 member = TREE_OPERAND (t, 1);
13989 if (BASELINK_P (member))
13990 member = tsubst_baselink (member,
13991 non_reference (TREE_TYPE (object)),
13992 args, complain, in_decl);
13994 member = tsubst_copy (member, args, complain, in_decl);
13995 if (member == error_mark_node)
13996 return error_mark_node;
13998 if (type_dependent_expression_p (object))
13999 /* We can't do much here. */;
14000 else if (!CLASS_TYPE_P (object_type))
14002 if (SCALAR_TYPE_P (object_type))
14004 tree s = NULL_TREE;
14005 tree dtor = member;
14007 if (TREE_CODE (dtor) == SCOPE_REF)
14009 s = TREE_OPERAND (dtor, 0);
14010 dtor = TREE_OPERAND (dtor, 1);
14012 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14014 dtor = TREE_OPERAND (dtor, 0);
14016 return finish_pseudo_destructor_expr (object, s, dtor);
14020 else if (TREE_CODE (member) == SCOPE_REF
14021 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14023 /* Lookup the template functions now that we know what the
14025 tree scope = TREE_OPERAND (member, 0);
14026 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14027 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14028 member = lookup_qualified_name (scope, tmpl,
14029 /*is_type_p=*/false,
14030 /*complain=*/false);
14031 if (BASELINK_P (member))
14033 BASELINK_FUNCTIONS (member)
14034 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14036 member = (adjust_result_of_qualified_name_lookup
14037 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14042 qualified_name_lookup_error (scope, tmpl, member,
14044 return error_mark_node;
14047 else if (TREE_CODE (member) == SCOPE_REF
14048 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14049 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14051 if (complain & tf_error)
14053 if (TYPE_P (TREE_OPERAND (member, 0)))
14054 error ("%qT is not a class or namespace",
14055 TREE_OPERAND (member, 0));
14057 error ("%qD is not a class or namespace",
14058 TREE_OPERAND (member, 0));
14060 return error_mark_node;
14062 else if (TREE_CODE (member) == FIELD_DECL)
14063 return finish_non_static_data_member (member, object, NULL_TREE);
14065 return finish_class_member_access_expr (object, member,
14066 /*template_p=*/false,
14072 (RECUR (TREE_OPERAND (t, 0)));
14076 VEC(constructor_elt,gc) *n;
14077 constructor_elt *ce;
14078 unsigned HOST_WIDE_INT idx;
14079 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14080 bool process_index_p;
14082 bool need_copy_p = false;
14085 if (type == error_mark_node)
14086 return error_mark_node;
14088 /* digest_init will do the wrong thing if we let it. */
14089 if (type && TYPE_PTRMEMFUNC_P (type))
14092 /* We do not want to process the index of aggregate
14093 initializers as they are identifier nodes which will be
14094 looked up by digest_init. */
14095 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14097 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14098 newlen = VEC_length (constructor_elt, n);
14099 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14101 if (ce->index && process_index_p)
14102 ce->index = RECUR (ce->index);
14104 if (PACK_EXPANSION_P (ce->value))
14106 /* Substitute into the pack expansion. */
14107 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14110 if (ce->value == error_mark_node
14111 || PACK_EXPANSION_P (ce->value))
14113 else if (TREE_VEC_LENGTH (ce->value) == 1)
14114 /* Just move the argument into place. */
14115 ce->value = TREE_VEC_ELT (ce->value, 0);
14118 /* Update the length of the final CONSTRUCTOR
14119 arguments vector, and note that we will need to
14121 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14122 need_copy_p = true;
14126 ce->value = RECUR (ce->value);
14131 VEC(constructor_elt,gc) *old_n = n;
14133 n = VEC_alloc (constructor_elt, gc, newlen);
14134 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14136 if (TREE_CODE (ce->value) == TREE_VEC)
14138 int i, len = TREE_VEC_LENGTH (ce->value);
14139 for (i = 0; i < len; ++i)
14140 CONSTRUCTOR_APPEND_ELT (n, 0,
14141 TREE_VEC_ELT (ce->value, i));
14144 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14148 r = build_constructor (init_list_type_node, n);
14149 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14151 if (TREE_HAS_CONSTRUCTOR (t))
14152 return finish_compound_literal (type, r, complain);
14154 TREE_TYPE (r) = type;
14160 tree operand_0 = TREE_OPERAND (t, 0);
14161 if (TYPE_P (operand_0))
14163 operand_0 = tsubst (operand_0, args, complain, in_decl);
14164 return get_typeid (operand_0);
14168 operand_0 = RECUR (operand_0);
14169 return build_typeid (operand_0);
14180 tree r = tsubst_copy (t, args, complain, in_decl);
14182 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14183 /* If the original type was a reference, we'll be wrapped in
14184 the appropriate INDIRECT_REF. */
14185 r = convert_from_reference (r);
14190 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14191 tsubst (TREE_TYPE (t), args, complain, in_decl));
14193 case OFFSETOF_EXPR:
14194 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14198 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14199 complain, in_decl);
14201 tree type2 = TRAIT_EXPR_TYPE2 (t);
14203 type2 = tsubst_copy (type2, args, complain, in_decl);
14205 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14210 tree old_stmt_expr = cur_stmt_expr;
14211 tree stmt_expr = begin_stmt_expr ();
14213 cur_stmt_expr = stmt_expr;
14214 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14215 integral_constant_expression_p);
14216 stmt_expr = finish_stmt_expr (stmt_expr, false);
14217 cur_stmt_expr = old_stmt_expr;
14219 /* If the resulting list of expression statement is empty,
14220 fold it further into void_zero_node. */
14221 if (empty_expr_stmt_p (stmt_expr))
14222 stmt_expr = void_zero_node;
14228 t = tsubst_copy (t, args, complain, in_decl);
14229 /* As in finish_id_expression, we resolve enumeration constants
14230 to their underlying values. */
14231 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14233 used_types_insert (TREE_TYPE (t));
14234 return DECL_INITIAL (t);
14240 tree r = build_lambda_expr ();
14242 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14243 LAMBDA_EXPR_CLOSURE (r) = type;
14244 CLASSTYPE_LAMBDA_EXPR (type) = r;
14246 LAMBDA_EXPR_LOCATION (r)
14247 = LAMBDA_EXPR_LOCATION (t);
14248 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14249 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14250 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14251 LAMBDA_EXPR_DISCRIMINATOR (r)
14252 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14253 LAMBDA_EXPR_EXTRA_SCOPE (r)
14254 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14255 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14257 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14258 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14261 LAMBDA_EXPR_RETURN_TYPE (r)
14262 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14264 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14265 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14267 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14268 determine_visibility (TYPE_NAME (type));
14269 /* Now that we know visibility, instantiate the type so we have a
14270 declaration of the op() for later calls to lambda_function. */
14271 complete_type (type);
14273 /* The capture list refers to closure members, so this needs to
14274 wait until after we finish instantiating the type. */
14275 LAMBDA_EXPR_CAPTURE_LIST (r)
14276 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14278 return build_lambda_object (r);
14282 /* We can get here for a constant initializer of non-dependent type.
14283 FIXME stop folding in cp_parser_initializer_clause. */
14284 gcc_assert (TREE_CONSTANT (t));
14286 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14287 TREE_CONSTANT (r) = true;
14292 /* Handle Objective-C++ constructs, if appropriate. */
14295 = objcp_tsubst_copy_and_build (t, args, complain,
14296 in_decl, /*function_p=*/false);
14300 return tsubst_copy (t, args, complain, in_decl);
14306 /* Verify that the instantiated ARGS are valid. For type arguments,
14307 make sure that the type's linkage is ok. For non-type arguments,
14308 make sure they are constants if they are integral or enumerations.
14309 Emit an error under control of COMPLAIN, and return TRUE on error. */
14312 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14314 if (ARGUMENT_PACK_P (t))
14316 tree vec = ARGUMENT_PACK_ARGS (t);
14317 int len = TREE_VEC_LENGTH (vec);
14318 bool result = false;
14321 for (i = 0; i < len; ++i)
14322 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14326 else if (TYPE_P (t))
14328 /* [basic.link]: A name with no linkage (notably, the name
14329 of a class or enumeration declared in a local scope)
14330 shall not be used to declare an entity with linkage.
14331 This implies that names with no linkage cannot be used as
14334 DR 757 relaxes this restriction for C++0x. */
14335 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14336 : no_linkage_check (t, /*relaxed_p=*/false));
14340 /* DR 488 makes use of a type with no linkage cause
14341 type deduction to fail. */
14342 if (complain & tf_error)
14344 if (TYPE_ANONYMOUS_P (nt))
14345 error ("%qT is/uses anonymous type", t);
14347 error ("template argument for %qD uses local type %qT",
14352 /* In order to avoid all sorts of complications, we do not
14353 allow variably-modified types as template arguments. */
14354 else if (variably_modified_type_p (t, NULL_TREE))
14356 if (complain & tf_error)
14357 error ("%qT is a variably modified type", t);
14361 /* A non-type argument of integral or enumerated type must be a
14363 else if (TREE_TYPE (t)
14364 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14365 && !TREE_CONSTANT (t))
14367 if (complain & tf_error)
14368 error ("integral expression %qE is not constant", t);
14375 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14377 int ix, len = DECL_NTPARMS (tmpl);
14378 bool result = false;
14380 for (ix = 0; ix != len; ix++)
14382 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14385 if (result && (complain & tf_error))
14386 error (" trying to instantiate %qD", tmpl);
14390 /* In C++0x, it's possible to have a function template whose type depends
14391 on itself recursively. This is most obvious with decltype, but can also
14392 occur with enumeration scope (c++/48969). So we need to catch infinite
14393 recursion and reject the substitution at deduction time; this function
14394 will return error_mark_node for any repeated substitution.
14396 This also catches excessive recursion such as when f<N> depends on
14397 f<N-1> across all integers, and returns error_mark_node for all the
14398 substitutions back up to the initial one.
14400 This is, of course, not reentrant. */
14403 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14405 static bool excessive_deduction_depth;
14406 static int deduction_depth;
14407 struct pending_template *old_last_pend = last_pending_template;
14408 struct tinst_level *old_error_tinst = last_error_tinst_level;
14410 tree fntype = TREE_TYPE (fn);
14414 if (excessive_deduction_depth)
14415 return error_mark_node;
14417 tinst = build_tree_list (fn, targs);
14418 if (!push_tinst_level (tinst))
14420 excessive_deduction_depth = true;
14422 return error_mark_node;
14425 input_location = DECL_SOURCE_LOCATION (fn);
14427 push_deduction_access_scope (fn);
14428 r = tsubst (fntype, targs, complain, NULL_TREE);
14429 pop_deduction_access_scope (fn);
14432 if (excessive_deduction_depth)
14434 r = error_mark_node;
14435 if (deduction_depth == 0)
14436 /* Reset once we're all the way out. */
14437 excessive_deduction_depth = false;
14440 pop_tinst_level ();
14441 /* We can't free this if a pending_template entry or last_error_tinst_level
14442 is pointing at it. */
14443 if (last_pending_template == old_last_pend
14444 && last_error_tinst_level == old_error_tinst)
14449 /* Instantiate the indicated variable or function template TMPL with
14450 the template arguments in TARG_PTR. */
14453 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14455 tree targ_ptr = orig_args;
14459 HOST_WIDE_INT saved_processing_template_decl;
14461 if (tmpl == error_mark_node)
14462 return error_mark_node;
14464 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14466 /* If this function is a clone, handle it specially. */
14467 if (DECL_CLONED_FUNCTION_P (tmpl))
14472 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14473 DECL_CLONED_FUNCTION. */
14474 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14475 targ_ptr, complain);
14476 if (spec == error_mark_node)
14477 return error_mark_node;
14479 /* Look for the clone. */
14480 FOR_EACH_CLONE (clone, spec)
14481 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14483 /* We should always have found the clone by now. */
14484 gcc_unreachable ();
14488 /* Check to see if we already have this specialization. */
14489 gen_tmpl = most_general_template (tmpl);
14490 if (tmpl != gen_tmpl)
14491 /* The TMPL is a partial instantiation. To get a full set of
14492 arguments we must add the arguments used to perform the
14493 partial instantiation. */
14494 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14497 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14498 but it doesn't seem to be on the hot path. */
14499 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14501 gcc_assert (tmpl == gen_tmpl
14502 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14504 || fndecl == NULL_TREE);
14506 if (spec != NULL_TREE)
14509 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14511 return error_mark_node;
14513 /* We are building a FUNCTION_DECL, during which the access of its
14514 parameters and return types have to be checked. However this
14515 FUNCTION_DECL which is the desired context for access checking
14516 is not built yet. We solve this chicken-and-egg problem by
14517 deferring all checks until we have the FUNCTION_DECL. */
14518 push_deferring_access_checks (dk_deferred);
14520 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
14521 (because, for example, we have encountered a non-dependent
14522 function call in the body of a template function and must now
14523 determine which of several overloaded functions will be called),
14524 within the instantiation itself we are not processing a
14526 saved_processing_template_decl = processing_template_decl;
14527 processing_template_decl = 0;
14528 /* Substitute template parameters to obtain the specialization. */
14529 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14530 targ_ptr, complain, gen_tmpl);
14531 processing_template_decl = saved_processing_template_decl;
14532 if (fndecl == error_mark_node)
14533 return error_mark_node;
14535 /* Now we know the specialization, compute access previously
14537 push_access_scope (fndecl);
14539 /* Some typedefs referenced from within the template code need to be access
14540 checked at template instantiation time, i.e now. These types were
14541 added to the template at parsing time. Let's get those and perfom
14542 the acces checks then. */
14543 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14544 perform_deferred_access_checks ();
14545 pop_access_scope (fndecl);
14546 pop_deferring_access_checks ();
14548 /* The DECL_TI_TEMPLATE should always be the immediate parent
14549 template, not the most general template. */
14550 DECL_TI_TEMPLATE (fndecl) = tmpl;
14552 /* If we've just instantiated the main entry point for a function,
14553 instantiate all the alternate entry points as well. We do this
14554 by cloning the instantiation of the main entry point, not by
14555 instantiating the template clones. */
14556 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14557 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14562 /* Wrapper for instantiate_template_1. */
14565 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14568 timevar_push (TV_TEMPLATE_INST);
14569 ret = instantiate_template_1 (tmpl, orig_args, complain);
14570 timevar_pop (TV_TEMPLATE_INST);
14574 /* We're going to do deduction substitution on the type of TMPL, a function
14575 template. In C++11 mode, push into that access scope. In C++03 mode,
14576 disable access checking. */
14579 push_deduction_access_scope (tree tmpl)
14581 if (cxx_dialect >= cxx0x)
14583 int ptd = processing_template_decl;
14584 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14585 /* Preserve processing_template_decl across push_to_top_level. */
14586 if (ptd && !processing_template_decl)
14587 ++processing_template_decl;
14590 push_deferring_access_checks (dk_no_check);
14593 /* And pop back out. */
14596 pop_deduction_access_scope (tree tmpl)
14598 if (cxx_dialect >= cxx0x)
14599 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14601 pop_deferring_access_checks ();
14604 /* PARM is a template parameter pack for FN. Returns true iff
14605 PARM is used in a deducible way in the argument list of FN. */
14608 pack_deducible_p (tree parm, tree fn)
14610 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14611 for (; t; t = TREE_CHAIN (t))
14613 tree type = TREE_VALUE (t);
14615 if (!PACK_EXPANSION_P (type))
14617 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14618 packs; packs = TREE_CHAIN (packs))
14619 if (TREE_VALUE (packs) == parm)
14621 /* The template parameter pack is used in a function parameter
14622 pack. If this is the end of the parameter list, the
14623 template parameter pack is deducible. */
14624 if (TREE_CHAIN (t) == void_list_node)
14627 /* Otherwise, not. Well, it could be deduced from
14628 a non-pack parameter, but doing so would end up with
14629 a deduction mismatch, so don't bother. */
14633 /* The template parameter pack isn't used in any function parameter
14634 packs, but it might be used deeper, e.g. tuple<Args...>. */
14638 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14639 NARGS elements of the arguments that are being used when calling
14640 it. TARGS is a vector into which the deduced template arguments
14643 Return zero for success, 2 for an incomplete match that doesn't resolve
14644 all the types, and 1 for complete failure. An error message will be
14645 printed only for an incomplete match.
14647 If FN is a conversion operator, or we are trying to produce a specific
14648 specialization, RETURN_TYPE is the return type desired.
14650 The EXPLICIT_TARGS are explicit template arguments provided via a
14653 The parameter STRICT is one of:
14656 We are deducing arguments for a function call, as in
14657 [temp.deduct.call].
14660 We are deducing arguments for a conversion function, as in
14661 [temp.deduct.conv].
14664 We are deducing arguments when doing an explicit instantiation
14665 as in [temp.explicit], when determining an explicit specialization
14666 as in [temp.expl.spec], or when taking the address of a function
14667 template, as in [temp.deduct.funcaddr]. */
14670 fn_type_unification (tree fn,
14671 tree explicit_targs,
14674 unsigned int nargs,
14676 unification_kind_t strict,
14684 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14686 fntype = TREE_TYPE (fn);
14687 if (explicit_targs)
14691 The specified template arguments must match the template
14692 parameters in kind (i.e., type, nontype, template), and there
14693 must not be more arguments than there are parameters;
14694 otherwise type deduction fails.
14696 Nontype arguments must match the types of the corresponding
14697 nontype template parameters, or must be convertible to the
14698 types of the corresponding nontype parameters as specified in
14699 _temp.arg.nontype_, otherwise type deduction fails.
14701 All references in the function type of the function template
14702 to the corresponding template parameters are replaced by the
14703 specified template argument values. If a substitution in a
14704 template parameter or in the function type of the function
14705 template results in an invalid type, type deduction fails. */
14706 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14707 int i, len = TREE_VEC_LENGTH (tparms);
14708 tree converted_args;
14709 bool incomplete = false;
14711 if (explicit_targs == error_mark_node)
14712 return unify_invalid (explain_p);
14715 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14717 ? tf_warning_or_error
14719 /*require_all_args=*/false,
14720 /*use_default_args=*/false));
14721 if (converted_args == error_mark_node)
14724 /* Substitute the explicit args into the function type. This is
14725 necessary so that, for instance, explicitly declared function
14726 arguments can match null pointed constants. If we were given
14727 an incomplete set of explicit args, we must not do semantic
14728 processing during substitution as we could create partial
14730 for (i = 0; i < len; i++)
14732 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14733 bool parameter_pack = false;
14734 tree targ = TREE_VEC_ELT (converted_args, i);
14736 /* Dig out the actual parm. */
14737 if (TREE_CODE (parm) == TYPE_DECL
14738 || TREE_CODE (parm) == TEMPLATE_DECL)
14740 parm = TREE_TYPE (parm);
14741 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14743 else if (TREE_CODE (parm) == PARM_DECL)
14745 parm = DECL_INITIAL (parm);
14746 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14749 if (!parameter_pack && targ == NULL_TREE)
14750 /* No explicit argument for this template parameter. */
14753 if (parameter_pack && pack_deducible_p (parm, fn))
14755 /* Mark the argument pack as "incomplete". We could
14756 still deduce more arguments during unification.
14757 We remove this mark in type_unification_real. */
14760 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14761 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14762 = ARGUMENT_PACK_ARGS (targ);
14765 /* We have some incomplete argument packs. */
14770 processing_template_decl += incomplete;
14771 fntype = deduction_tsubst_fntype (fn, converted_args,
14773 ? tf_warning_or_error
14775 processing_template_decl -= incomplete;
14777 if (fntype == error_mark_node)
14780 /* Place the explicitly specified arguments in TARGS. */
14781 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14782 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14785 /* Never do unification on the 'this' parameter. */
14786 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14792 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14793 new_args = XALLOCAVEC (tree, nargs + 1);
14794 new_args[0] = return_type;
14795 memcpy (new_args + 1, args, nargs * sizeof (tree));
14800 /* We allow incomplete unification without an error message here
14801 because the standard doesn't seem to explicitly prohibit it. Our
14802 callers must be ready to deal with unification failures in any
14804 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14805 targs, parms, args, nargs, /*subr=*/0,
14806 strict, flags, explain_p);
14808 /* Now that we have bindings for all of the template arguments,
14809 ensure that the arguments deduced for the template template
14810 parameters have compatible template parameter lists. We cannot
14811 check this property before we have deduced all template
14812 arguments, because the template parameter types of a template
14813 template parameter might depend on prior template parameters
14814 deduced after the template template parameter. The following
14815 ill-formed example illustrates this issue:
14817 template<typename T, template<T> class C> void f(C<5>, T);
14819 template<int N> struct X {};
14822 f(X<5>(), 5l); // error: template argument deduction fails
14825 The template parameter list of 'C' depends on the template type
14826 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14827 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14828 time that we deduce 'C'. */
14830 && !template_template_parm_bindings_ok_p
14831 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14832 return unify_inconsistent_template_template_parameters (explain_p);
14835 /* All is well so far. Now, check:
14839 When all template arguments have been deduced, all uses of
14840 template parameters in nondeduced contexts are replaced with
14841 the corresponding deduced argument values. If the
14842 substitution results in an invalid type, as described above,
14843 type deduction fails. */
14845 tree substed = deduction_tsubst_fntype (fn, targs,
14847 ? tf_warning_or_error
14849 if (substed == error_mark_node)
14852 /* If we're looking for an exact match, check that what we got
14853 is indeed an exact match. It might not be if some template
14854 parameters are used in non-deduced contexts. */
14855 if (strict == DEDUCE_EXACT)
14860 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14862 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14863 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14864 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14865 return unify_type_mismatch (explain_p, args[i],
14866 TREE_VALUE (sarg));
14873 /* Adjust types before performing type deduction, as described in
14874 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14875 sections are symmetric. PARM is the type of a function parameter
14876 or the return type of the conversion function. ARG is the type of
14877 the argument passed to the call, or the type of the value
14878 initialized with the result of the conversion function.
14879 ARG_EXPR is the original argument expression, which may be null. */
14882 maybe_adjust_types_for_deduction (unification_kind_t strict,
14896 /* Swap PARM and ARG throughout the remainder of this
14897 function; the handling is precisely symmetric since PARM
14898 will initialize ARG rather than vice versa. */
14906 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14907 too, but here handle it by stripping the reference from PARM
14908 rather than by adding it to ARG. */
14909 if (TREE_CODE (*parm) == REFERENCE_TYPE
14910 && TYPE_REF_IS_RVALUE (*parm)
14911 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14912 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14913 && TREE_CODE (*arg) == REFERENCE_TYPE
14914 && !TYPE_REF_IS_RVALUE (*arg))
14915 *parm = TREE_TYPE (*parm);
14916 /* Nothing else to do in this case. */
14920 gcc_unreachable ();
14923 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14925 /* [temp.deduct.call]
14927 If P is not a reference type:
14929 --If A is an array type, the pointer type produced by the
14930 array-to-pointer standard conversion (_conv.array_) is
14931 used in place of A for type deduction; otherwise,
14933 --If A is a function type, the pointer type produced by
14934 the function-to-pointer standard conversion
14935 (_conv.func_) is used in place of A for type deduction;
14938 --If A is a cv-qualified type, the top level
14939 cv-qualifiers of A's type are ignored for type
14941 if (TREE_CODE (*arg) == ARRAY_TYPE)
14942 *arg = build_pointer_type (TREE_TYPE (*arg));
14943 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14944 *arg = build_pointer_type (*arg);
14946 *arg = TYPE_MAIN_VARIANT (*arg);
14949 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14950 of the form T&&, where T is a template parameter, and the argument
14951 is an lvalue, T is deduced as A& */
14952 if (TREE_CODE (*parm) == REFERENCE_TYPE
14953 && TYPE_REF_IS_RVALUE (*parm)
14954 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14955 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14956 && (arg_expr ? real_lvalue_p (arg_expr)
14957 /* try_one_overload doesn't provide an arg_expr, but
14958 functions are always lvalues. */
14959 : TREE_CODE (*arg) == FUNCTION_TYPE))
14960 *arg = build_reference_type (*arg);
14962 /* [temp.deduct.call]
14964 If P is a cv-qualified type, the top level cv-qualifiers
14965 of P's type are ignored for type deduction. If P is a
14966 reference type, the type referred to by P is used for
14968 *parm = TYPE_MAIN_VARIANT (*parm);
14969 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14971 *parm = TREE_TYPE (*parm);
14972 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14975 /* DR 322. For conversion deduction, remove a reference type on parm
14976 too (which has been swapped into ARG). */
14977 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14978 *arg = TREE_TYPE (*arg);
14983 /* Subroutine of unify_one_argument. PARM is a function parameter of a
14984 template which does contain any deducible template parameters; check if
14985 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
14986 unify_one_argument. */
14989 check_non_deducible_conversion (tree parm, tree arg, int strict,
14990 int flags, bool explain_p)
14995 type = TREE_TYPE (arg);
14999 if (same_type_p (parm, type))
15000 return unify_success (explain_p);
15002 if (strict == DEDUCE_CONV)
15004 if (can_convert_arg (type, parm, NULL_TREE, flags))
15005 return unify_success (explain_p);
15007 else if (strict != DEDUCE_EXACT)
15009 if (can_convert_arg (parm, type,
15010 TYPE_P (arg) ? NULL_TREE : arg,
15012 return unify_success (explain_p);
15015 if (strict == DEDUCE_EXACT)
15016 return unify_type_mismatch (explain_p, parm, arg);
15018 return unify_arg_conversion (explain_p, parm, type, arg);
15021 /* Subroutine of type_unification_real and unify_pack_expansion to
15022 handle unification of a single P/A pair. Parameters are as
15023 for those functions. */
15026 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15027 int subr, unification_kind_t strict, int flags,
15030 tree arg_expr = NULL_TREE;
15033 if (arg == error_mark_node || parm == error_mark_node)
15034 return unify_invalid (explain_p);
15035 if (arg == unknown_type_node)
15036 /* We can't deduce anything from this, but we might get all the
15037 template args from other function args. */
15038 return unify_success (explain_p);
15040 /* FIXME uses_deducible_template_parms */
15041 if (TYPE_P (parm) && !uses_template_parms (parm))
15042 return check_non_deducible_conversion (parm, arg, strict, flags,
15048 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15049 | UNIFY_ALLOW_MORE_CV_QUAL
15050 | UNIFY_ALLOW_DERIVED);
15054 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15058 arg_strict = UNIFY_ALLOW_NONE;
15062 gcc_unreachable ();
15065 /* We only do these transformations if this is the top-level
15066 parameter_type_list in a call or declaration matching; in other
15067 situations (nested function declarators, template argument lists) we
15068 won't be comparing a type to an expression, and we don't do any type
15074 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15075 if (type_unknown_p (arg))
15077 /* [temp.deduct.type] A template-argument can be
15078 deduced from a pointer to function or pointer
15079 to member function argument if the set of
15080 overloaded functions does not contain function
15081 templates and at most one of a set of
15082 overloaded functions provides a unique
15085 if (resolve_overloaded_unification
15086 (tparms, targs, parm, arg, strict,
15087 arg_strict, explain_p))
15088 return unify_success (explain_p);
15089 return unify_overload_resolution_failure (explain_p, arg);
15093 arg = unlowered_expr_type (arg);
15094 if (arg == error_mark_node)
15095 return unify_invalid (explain_p);
15099 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15102 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15103 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15105 /* For deduction from an init-list we need the actual list. */
15106 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15108 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15111 /* Most parms like fn_type_unification.
15113 If SUBR is 1, we're being called recursively (to unify the
15114 arguments of a function or method parameter of a function
15118 type_unification_real (tree tparms,
15122 unsigned int xnargs,
15124 unification_kind_t strict,
15130 int ntparms = TREE_VEC_LENGTH (tparms);
15131 int saw_undeduced = 0;
15134 unsigned int nargs;
15137 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15138 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15139 gcc_assert (ntparms > 0);
15141 /* Reset the number of non-defaulted template arguments contained
15143 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15151 while (parms && parms != void_list_node
15154 parm = TREE_VALUE (parms);
15156 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15157 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15158 /* For a function parameter pack that occurs at the end of the
15159 parameter-declaration-list, the type A of each remaining
15160 argument of the call is compared with the type P of the
15161 declarator-id of the function parameter pack. */
15164 parms = TREE_CHAIN (parms);
15166 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15167 /* For a function parameter pack that does not occur at the
15168 end of the parameter-declaration-list, the type of the
15169 parameter pack is a non-deduced context. */
15175 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15181 && parms != void_list_node
15182 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15184 /* Unify the remaining arguments with the pack expansion type. */
15186 tree parmvec = make_tree_vec (1);
15188 /* Allocate a TREE_VEC and copy in all of the arguments */
15189 argvec = make_tree_vec (nargs - ia);
15190 for (i = 0; ia < nargs; ++ia, ++i)
15191 TREE_VEC_ELT (argvec, i) = args[ia];
15193 /* Copy the parameter into parmvec. */
15194 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15195 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15196 /*subr=*/subr, explain_p))
15199 /* Advance to the end of the list of parameters. */
15200 parms = TREE_CHAIN (parms);
15203 /* Fail if we've reached the end of the parm list, and more args
15204 are present, and the parm list isn't variadic. */
15205 if (ia < nargs && parms == void_list_node)
15206 return unify_too_many_arguments (explain_p, nargs, ia);
15207 /* Fail if parms are left and they don't have default values. */
15208 if (parms && parms != void_list_node
15209 && TREE_PURPOSE (parms) == NULL_TREE)
15211 unsigned int count = nargs;
15213 while (p && p != void_list_node)
15216 p = TREE_CHAIN (p);
15218 return unify_too_few_arguments (explain_p, ia, count);
15223 tsubst_flags_t complain = (explain_p
15224 ? tf_warning_or_error
15227 /* Check to see if we need another pass before we start clearing
15228 ARGUMENT_PACK_INCOMPLETE_P. */
15229 for (i = 0; i < ntparms; i++)
15231 tree targ = TREE_VEC_ELT (targs, i);
15232 tree tparm = TREE_VEC_ELT (tparms, i);
15234 if (targ || tparm == error_mark_node)
15236 tparm = TREE_VALUE (tparm);
15238 /* If this is an undeduced nontype parameter that depends on
15239 a type parameter, try another pass; its type may have been
15240 deduced from a later argument than the one from which
15241 this parameter can be deduced. */
15242 if (TREE_CODE (tparm) == PARM_DECL
15243 && uses_template_parms (TREE_TYPE (tparm))
15244 && !saw_undeduced++)
15248 for (i = 0; i < ntparms; i++)
15250 tree targ = TREE_VEC_ELT (targs, i);
15251 tree tparm = TREE_VEC_ELT (tparms, i);
15253 /* Clear the "incomplete" flags on all argument packs now so that
15254 substituting them into later default arguments works. */
15255 if (targ && ARGUMENT_PACK_P (targ))
15257 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15258 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15261 if (targ || tparm == error_mark_node)
15263 tparm = TREE_VALUE (tparm);
15265 /* Core issue #226 (C++0x) [temp.deduct]:
15267 If a template argument has not been deduced, its
15268 default template argument, if any, is used.
15270 When we are in C++98 mode, TREE_PURPOSE will either
15271 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15272 to explicitly check cxx_dialect here. */
15273 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15275 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15276 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15277 location_t save_loc = input_location;
15279 input_location = DECL_SOURCE_LOCATION (parm);
15280 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15281 arg = convert_template_argument (parm, arg, targs, complain,
15283 input_location = save_loc;
15284 if (arg == error_mark_node)
15288 TREE_VEC_ELT (targs, i) = arg;
15289 /* The position of the first default template argument,
15290 is also the number of non-defaulted arguments in TARGS.
15292 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15293 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15298 /* If the type parameter is a parameter pack, then it will
15299 be deduced to an empty parameter pack. */
15300 if (template_parameter_pack_p (tparm))
15304 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15306 arg = make_node (NONTYPE_ARGUMENT_PACK);
15307 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15308 TREE_CONSTANT (arg) = 1;
15311 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15313 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15315 TREE_VEC_ELT (targs, i) = arg;
15319 return unify_parameter_deduction_failure (explain_p, tparm);
15322 #ifdef ENABLE_CHECKING
15323 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15324 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15327 return unify_success (explain_p);
15330 /* Subroutine of type_unification_real. Args are like the variables
15331 at the call site. ARG is an overloaded function (or template-id);
15332 we try deducing template args from each of the overloads, and if
15333 only one succeeds, we go with that. Modifies TARGS and returns
15334 true on success. */
15337 resolve_overloaded_unification (tree tparms,
15341 unification_kind_t strict,
15345 tree tempargs = copy_node (targs);
15347 tree goodfn = NULL_TREE;
15350 if (TREE_CODE (arg) == ADDR_EXPR)
15352 arg = TREE_OPERAND (arg, 0);
15358 if (TREE_CODE (arg) == COMPONENT_REF)
15359 /* Handle `&x' where `x' is some static or non-static member
15361 arg = TREE_OPERAND (arg, 1);
15363 if (TREE_CODE (arg) == OFFSET_REF)
15364 arg = TREE_OPERAND (arg, 1);
15366 /* Strip baselink information. */
15367 if (BASELINK_P (arg))
15368 arg = BASELINK_FUNCTIONS (arg);
15370 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15372 /* If we got some explicit template args, we need to plug them into
15373 the affected templates before we try to unify, in case the
15374 explicit args will completely resolve the templates in question. */
15377 tree expl_subargs = TREE_OPERAND (arg, 1);
15378 arg = TREE_OPERAND (arg, 0);
15380 for (; arg; arg = OVL_NEXT (arg))
15382 tree fn = OVL_CURRENT (arg);
15383 tree subargs, elem;
15385 if (TREE_CODE (fn) != TEMPLATE_DECL)
15388 ++processing_template_decl;
15389 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15390 expl_subargs, /*check_ret=*/false);
15391 if (subargs && !any_dependent_template_arguments_p (subargs))
15393 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15394 if (try_one_overload (tparms, targs, tempargs, parm,
15395 elem, strict, sub_strict, addr_p, explain_p)
15396 && (!goodfn || !decls_match (goodfn, elem)))
15404 --processing_template_decl;
15406 /* If no templates (or more than one) are fully resolved by the
15407 explicit arguments, this template-id is a non-deduced context; it
15408 could still be OK if we deduce all template arguments for the
15409 enclosing call through other arguments. */
15413 else if (TREE_CODE (arg) != OVERLOAD
15414 && TREE_CODE (arg) != FUNCTION_DECL)
15415 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15416 -- but the deduction does not succeed because the expression is
15417 not just the function on its own. */
15420 for (; arg; arg = OVL_NEXT (arg))
15421 if (try_one_overload (tparms, targs, tempargs, parm,
15422 TREE_TYPE (OVL_CURRENT (arg)),
15423 strict, sub_strict, addr_p, explain_p)
15424 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15426 goodfn = OVL_CURRENT (arg);
15430 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15431 to function or pointer to member function argument if the set of
15432 overloaded functions does not contain function templates and at most
15433 one of a set of overloaded functions provides a unique match.
15435 So if we found multiple possibilities, we return success but don't
15436 deduce anything. */
15440 int i = TREE_VEC_LENGTH (targs);
15442 if (TREE_VEC_ELT (tempargs, i))
15443 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15451 /* Core DR 115: In contexts where deduction is done and fails, or in
15452 contexts where deduction is not done, if a template argument list is
15453 specified and it, along with any default template arguments, identifies
15454 a single function template specialization, then the template-id is an
15455 lvalue for the function template specialization. */
15458 resolve_nondeduced_context (tree orig_expr)
15460 tree expr, offset, baselink;
15463 if (!type_unknown_p (orig_expr))
15468 offset = NULL_TREE;
15469 baselink = NULL_TREE;
15471 if (TREE_CODE (expr) == ADDR_EXPR)
15473 expr = TREE_OPERAND (expr, 0);
15476 if (TREE_CODE (expr) == OFFSET_REF)
15479 expr = TREE_OPERAND (expr, 1);
15481 if (BASELINK_P (expr))
15484 expr = BASELINK_FUNCTIONS (expr);
15487 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15490 tree goodfn = NULL_TREE;
15492 /* If we got some explicit template args, we need to plug them into
15493 the affected templates before we try to unify, in case the
15494 explicit args will completely resolve the templates in question. */
15496 tree expl_subargs = TREE_OPERAND (expr, 1);
15497 tree arg = TREE_OPERAND (expr, 0);
15498 tree badfn = NULL_TREE;
15499 tree badargs = NULL_TREE;
15501 for (; arg; arg = OVL_NEXT (arg))
15503 tree fn = OVL_CURRENT (arg);
15504 tree subargs, elem;
15506 if (TREE_CODE (fn) != TEMPLATE_DECL)
15509 ++processing_template_decl;
15510 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15511 expl_subargs, /*check_ret=*/false);
15512 if (subargs && !any_dependent_template_arguments_p (subargs))
15514 elem = instantiate_template (fn, subargs, tf_none);
15515 if (elem == error_mark_node)
15520 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15526 --processing_template_decl;
15530 mark_used (goodfn);
15533 expr = build_baselink (BASELINK_BINFO (baselink),
15534 BASELINK_ACCESS_BINFO (baselink),
15535 expr, BASELINK_OPTYPE (baselink));
15539 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15540 expr = build_offset_ref (base, expr, addr);
15543 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15546 else if (good == 0 && badargs)
15547 /* There were no good options and at least one bad one, so let the
15548 user know what the problem is. */
15549 instantiate_template (badfn, badargs, tf_warning_or_error);
15554 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15555 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15556 different overloads deduce different arguments for a given parm.
15557 ADDR_P is true if the expression for which deduction is being
15558 performed was of the form "& fn" rather than simply "fn".
15560 Returns 1 on success. */
15563 try_one_overload (tree tparms,
15568 unification_kind_t strict,
15577 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15578 to function or pointer to member function argument if the set of
15579 overloaded functions does not contain function templates and at most
15580 one of a set of overloaded functions provides a unique match.
15582 So if this is a template, just return success. */
15584 if (uses_template_parms (arg))
15587 if (TREE_CODE (arg) == METHOD_TYPE)
15588 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15590 arg = build_pointer_type (arg);
15592 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15594 /* We don't copy orig_targs for this because if we have already deduced
15595 some template args from previous args, unify would complain when we
15596 try to deduce a template parameter for the same argument, even though
15597 there isn't really a conflict. */
15598 nargs = TREE_VEC_LENGTH (targs);
15599 tempargs = make_tree_vec (nargs);
15601 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15604 /* First make sure we didn't deduce anything that conflicts with
15605 explicitly specified args. */
15606 for (i = nargs; i--; )
15608 tree elt = TREE_VEC_ELT (tempargs, i);
15609 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15613 else if (uses_template_parms (elt))
15614 /* Since we're unifying against ourselves, we will fill in
15615 template args used in the function parm list with our own
15616 template parms. Discard them. */
15617 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15618 else if (oldelt && !template_args_equal (oldelt, elt))
15622 for (i = nargs; i--; )
15624 tree elt = TREE_VEC_ELT (tempargs, i);
15627 TREE_VEC_ELT (targs, i) = elt;
15633 /* PARM is a template class (perhaps with unbound template
15634 parameters). ARG is a fully instantiated type. If ARG can be
15635 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15636 TARGS are as for unify. */
15639 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15642 tree copy_of_targs;
15644 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15645 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15646 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15649 /* We need to make a new template argument vector for the call to
15650 unify. If we used TARGS, we'd clutter it up with the result of
15651 the attempted unification, even if this class didn't work out.
15652 We also don't want to commit ourselves to all the unifications
15653 we've already done, since unification is supposed to be done on
15654 an argument-by-argument basis. In other words, consider the
15655 following pathological case:
15657 template <int I, int J, int K>
15660 template <int I, int J>
15661 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15663 template <int I, int J, int K>
15664 void f(S<I, J, K>, S<I, I, I>);
15673 Now, by the time we consider the unification involving `s2', we
15674 already know that we must have `f<0, 0, 0>'. But, even though
15675 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15676 because there are two ways to unify base classes of S<0, 1, 2>
15677 with S<I, I, I>. If we kept the already deduced knowledge, we
15678 would reject the possibility I=1. */
15679 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15681 /* If unification failed, we're done. */
15682 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15683 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15689 /* Given a template type PARM and a class type ARG, find the unique
15690 base type in ARG that is an instance of PARM. We do not examine
15691 ARG itself; only its base-classes. If there is not exactly one
15692 appropriate base class, return NULL_TREE. PARM may be the type of
15693 a partial specialization, as well as a plain template type. Used
15696 static enum template_base_result
15697 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15698 bool explain_p, tree *result)
15700 tree rval = NULL_TREE;
15703 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15705 binfo = TYPE_BINFO (complete_type (arg));
15708 /* The type could not be completed. */
15709 *result = NULL_TREE;
15710 return tbr_incomplete_type;
15713 /* Walk in inheritance graph order. The search order is not
15714 important, and this avoids multiple walks of virtual bases. */
15715 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15717 tree r = try_class_unification (tparms, targs, parm,
15718 BINFO_TYPE (binfo), explain_p);
15722 /* If there is more than one satisfactory baseclass, then:
15726 If they yield more than one possible deduced A, the type
15730 if (rval && !same_type_p (r, rval))
15732 *result = NULL_TREE;
15733 return tbr_ambiguous_baseclass;
15741 return tbr_success;
15744 /* Returns the level of DECL, which declares a template parameter. */
15747 template_decl_level (tree decl)
15749 switch (TREE_CODE (decl))
15752 case TEMPLATE_DECL:
15753 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15756 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15759 gcc_unreachable ();
15764 /* Decide whether ARG can be unified with PARM, considering only the
15765 cv-qualifiers of each type, given STRICT as documented for unify.
15766 Returns nonzero iff the unification is OK on that basis. */
15769 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15771 int arg_quals = cp_type_quals (arg);
15772 int parm_quals = cp_type_quals (parm);
15774 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15775 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15777 /* Although a CVR qualifier is ignored when being applied to a
15778 substituted template parameter ([8.3.2]/1 for example), that
15779 does not allow us to unify "const T" with "int&" because both
15780 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15781 It is ok when we're allowing additional CV qualifiers
15782 at the outer level [14.8.2.1]/3,1st bullet. */
15783 if ((TREE_CODE (arg) == REFERENCE_TYPE
15784 || TREE_CODE (arg) == FUNCTION_TYPE
15785 || TREE_CODE (arg) == METHOD_TYPE)
15786 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15789 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15790 && (parm_quals & TYPE_QUAL_RESTRICT))
15794 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15795 && (arg_quals & parm_quals) != parm_quals)
15798 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15799 && (parm_quals & arg_quals) != arg_quals)
15805 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15807 template_parm_level_and_index (tree parm, int* level, int* index)
15809 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15810 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15811 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15813 *index = TEMPLATE_TYPE_IDX (parm);
15814 *level = TEMPLATE_TYPE_LEVEL (parm);
15818 *index = TEMPLATE_PARM_IDX (parm);
15819 *level = TEMPLATE_PARM_LEVEL (parm);
15823 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15825 if (unify (TP, TA, P, A, S, EP)) \
15829 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15830 expansion at the end of PACKED_PARMS. Returns 0 if the type
15831 deduction succeeds, 1 otherwise. STRICT is the same as in
15832 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15833 call argument list. We'll need to adjust the arguments to make them
15834 types. SUBR tells us if this is from a recursive call to
15835 type_unification_real, or for comparing two template argument
15839 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15840 tree packed_args, unification_kind_t strict,
15841 bool subr, bool explain_p)
15844 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15845 tree pattern = PACK_EXPANSION_PATTERN (parm);
15846 tree pack, packs = NULL_TREE;
15847 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15848 int len = TREE_VEC_LENGTH (packed_args);
15850 /* Determine the parameter packs we will be deducing from the
15851 pattern, and record their current deductions. */
15852 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15853 pack; pack = TREE_CHAIN (pack))
15855 tree parm_pack = TREE_VALUE (pack);
15858 /* Determine the index and level of this parameter pack. */
15859 template_parm_level_and_index (parm_pack, &level, &idx);
15861 /* Keep track of the parameter packs and their corresponding
15863 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15864 TREE_TYPE (packs) = make_tree_vec (len - start);
15867 /* Loop through all of the arguments that have not yet been
15868 unified and unify each with the pattern. */
15869 for (i = start; i < len; i++)
15872 bool any_explicit = false;
15873 tree arg = TREE_VEC_ELT (packed_args, i);
15875 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
15876 or the element of its argument pack at the current index if
15877 this argument was explicitly specified. */
15878 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15882 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15885 if (TREE_VALUE (pack)
15886 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
15887 && (i < TREE_VEC_LENGTH (pargs)))
15889 any_explicit = true;
15890 arg = TREE_VEC_ELT (pargs, i);
15892 TMPL_ARG (targs, level, idx) = arg;
15895 /* If we had explicit template arguments, substitute them into the
15896 pattern before deduction. */
15899 /* Some arguments might still be unspecified or dependent. */
15901 ++processing_template_decl;
15902 dependent = any_dependent_template_arguments_p (targs);
15904 --processing_template_decl;
15905 parm = tsubst (pattern, targs,
15906 explain_p ? tf_warning_or_error : tf_none,
15909 --processing_template_decl;
15910 if (parm == error_mark_node)
15916 /* Unify the pattern with the current argument. */
15917 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15918 LOOKUP_IMPLICIT, explain_p))
15921 /* For each parameter pack, collect the deduced value. */
15922 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15925 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15927 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15928 TMPL_ARG (targs, level, idx);
15932 /* Verify that the results of unification with the parameter packs
15933 produce results consistent with what we've seen before, and make
15934 the deduced argument packs available. */
15935 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15937 tree old_pack = TREE_VALUE (pack);
15938 tree new_args = TREE_TYPE (pack);
15939 int i, len = TREE_VEC_LENGTH (new_args);
15941 bool nondeduced_p = false;
15943 /* By default keep the original deduced argument pack.
15944 If necessary, more specific code is going to update the
15945 resulting deduced argument later down in this function. */
15946 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15947 TMPL_ARG (targs, level, idx) = old_pack;
15949 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15950 actually deduce anything. */
15951 for (i = 0; i < len && !nondeduced_p; ++i)
15952 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15953 nondeduced_p = true;
15957 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15959 /* If we had fewer function args than explicit template args,
15960 just use the explicits. */
15961 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15962 int explicit_len = TREE_VEC_LENGTH (explicit_args);
15963 if (len < explicit_len)
15964 new_args = explicit_args;
15970 /* Build the deduced *_ARGUMENT_PACK. */
15971 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15973 result = make_node (NONTYPE_ARGUMENT_PACK);
15974 TREE_TYPE (result) =
15975 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15976 TREE_CONSTANT (result) = 1;
15979 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15981 SET_ARGUMENT_PACK_ARGS (result, new_args);
15983 /* Note the deduced argument packs for this parameter
15985 TMPL_ARG (targs, level, idx) = result;
15987 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15988 && (ARGUMENT_PACK_ARGS (old_pack)
15989 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15991 /* We only had the explicitly-provided arguments before, but
15992 now we have a complete set of arguments. */
15993 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15995 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15996 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15997 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16001 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16002 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16004 if (!comp_template_args_with_info (old_args, new_args,
16005 &bad_old_arg, &bad_new_arg))
16006 /* Inconsistent unification of this parameter pack. */
16007 return unify_parameter_pack_inconsistent (explain_p,
16013 return unify_success (explain_p);
16016 /* Deduce the value of template parameters. TPARMS is the (innermost)
16017 set of template parameters to a template. TARGS is the bindings
16018 for those template parameters, as determined thus far; TARGS may
16019 include template arguments for outer levels of template parameters
16020 as well. PARM is a parameter to a template function, or a
16021 subcomponent of that parameter; ARG is the corresponding argument.
16022 This function attempts to match PARM with ARG in a manner
16023 consistent with the existing assignments in TARGS. If more values
16024 are deduced, then TARGS is updated.
16026 Returns 0 if the type deduction succeeds, 1 otherwise. The
16027 parameter STRICT is a bitwise or of the following flags:
16030 Require an exact match between PARM and ARG.
16031 UNIFY_ALLOW_MORE_CV_QUAL:
16032 Allow the deduced ARG to be more cv-qualified (by qualification
16033 conversion) than ARG.
16034 UNIFY_ALLOW_LESS_CV_QUAL:
16035 Allow the deduced ARG to be less cv-qualified than ARG.
16036 UNIFY_ALLOW_DERIVED:
16037 Allow the deduced ARG to be a template base class of ARG,
16038 or a pointer to a template base class of the type pointed to by
16040 UNIFY_ALLOW_INTEGER:
16041 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16042 case for more information.
16043 UNIFY_ALLOW_OUTER_LEVEL:
16044 This is the outermost level of a deduction. Used to determine validity
16045 of qualification conversions. A valid qualification conversion must
16046 have const qualified pointers leading up to the inner type which
16047 requires additional CV quals, except at the outer level, where const
16048 is not required [conv.qual]. It would be normal to set this flag in
16049 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16050 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16051 This is the outermost level of a deduction, and PARM can be more CV
16052 qualified at this point.
16053 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16054 This is the outermost level of a deduction, and PARM can be less CV
16055 qualified at this point. */
16058 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16064 int strict_in = strict;
16066 /* I don't think this will do the right thing with respect to types.
16067 But the only case I've seen it in so far has been array bounds, where
16068 signedness is the only information lost, and I think that will be
16070 while (TREE_CODE (parm) == NOP_EXPR)
16071 parm = TREE_OPERAND (parm, 0);
16073 if (arg == error_mark_node)
16074 return unify_invalid (explain_p);
16075 if (arg == unknown_type_node
16076 || arg == init_list_type_node)
16077 /* We can't deduce anything from this, but we might get all the
16078 template args from other function args. */
16079 return unify_success (explain_p);
16081 /* If PARM uses template parameters, then we can't bail out here,
16082 even if ARG == PARM, since we won't record unifications for the
16083 template parameters. We might need them if we're trying to
16084 figure out which of two things is more specialized. */
16085 if (arg == parm && !uses_template_parms (parm))
16086 return unify_success (explain_p);
16088 /* Handle init lists early, so the rest of the function can assume
16089 we're dealing with a type. */
16090 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16094 tree orig_parm = parm;
16096 /* Replace T with std::initializer_list<T> for deduction. */
16097 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16098 && flag_deduce_init_list)
16099 parm = listify (parm);
16101 if (!is_std_init_list (parm))
16102 /* We can only deduce from an initializer list argument if the
16103 parameter is std::initializer_list; otherwise this is a
16104 non-deduced context. */
16105 return unify_success (explain_p);
16107 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16109 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16111 int elt_strict = strict;
16113 if (elt == error_mark_node)
16114 return unify_invalid (explain_p);
16116 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16118 tree type = TREE_TYPE (elt);
16119 /* It should only be possible to get here for a call. */
16120 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16121 elt_strict |= maybe_adjust_types_for_deduction
16122 (DEDUCE_CALL, &elttype, &type, elt);
16126 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16130 /* If the std::initializer_list<T> deduction worked, replace the
16131 deduced A with std::initializer_list<A>. */
16132 if (orig_parm != parm)
16134 idx = TEMPLATE_TYPE_IDX (orig_parm);
16135 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16136 targ = listify (targ);
16137 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16139 return unify_success (explain_p);
16142 /* Immediately reject some pairs that won't unify because of
16143 cv-qualification mismatches. */
16144 if (TREE_CODE (arg) == TREE_CODE (parm)
16146 /* It is the elements of the array which hold the cv quals of an array
16147 type, and the elements might be template type parms. We'll check
16148 when we recurse. */
16149 && TREE_CODE (arg) != ARRAY_TYPE
16150 /* We check the cv-qualifiers when unifying with template type
16151 parameters below. We want to allow ARG `const T' to unify with
16152 PARM `T' for example, when computing which of two templates
16153 is more specialized, for example. */
16154 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16155 && !check_cv_quals_for_unify (strict_in, arg, parm))
16156 return unify_cv_qual_mismatch (explain_p, parm, arg);
16158 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16159 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16160 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16161 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16162 strict &= ~UNIFY_ALLOW_DERIVED;
16163 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16164 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16166 switch (TREE_CODE (parm))
16168 case TYPENAME_TYPE:
16170 case UNBOUND_CLASS_TEMPLATE:
16171 /* In a type which contains a nested-name-specifier, template
16172 argument values cannot be deduced for template parameters used
16173 within the nested-name-specifier. */
16174 return unify_success (explain_p);
16176 case TEMPLATE_TYPE_PARM:
16177 case TEMPLATE_TEMPLATE_PARM:
16178 case BOUND_TEMPLATE_TEMPLATE_PARM:
16179 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16180 if (tparm == error_mark_node)
16181 return unify_invalid (explain_p);
16183 if (TEMPLATE_TYPE_LEVEL (parm)
16184 != template_decl_level (tparm))
16185 /* The PARM is not one we're trying to unify. Just check
16186 to see if it matches ARG. */
16188 if (TREE_CODE (arg) == TREE_CODE (parm)
16189 && same_type_p (parm, arg))
16190 return unify_success (explain_p);
16192 return unify_type_mismatch (explain_p, parm, arg);
16194 idx = TEMPLATE_TYPE_IDX (parm);
16195 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16196 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16198 /* Check for mixed types and values. */
16199 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16200 && TREE_CODE (tparm) != TYPE_DECL)
16201 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16202 && TREE_CODE (tparm) != TEMPLATE_DECL))
16203 gcc_unreachable ();
16205 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16207 /* ARG must be constructed from a template class or a template
16208 template parameter. */
16209 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16210 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16211 return unify_template_deduction_failure (explain_p, parm, arg);
16214 tree parmvec = TYPE_TI_ARGS (parm);
16215 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16216 tree full_argvec = add_to_template_args (targs, argvec);
16218 = DECL_INNERMOST_TEMPLATE_PARMS
16219 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16221 int parm_variadic_p = 0;
16223 /* The resolution to DR150 makes clear that default
16224 arguments for an N-argument may not be used to bind T
16225 to a template template parameter with fewer than N
16226 parameters. It is not safe to permit the binding of
16227 default arguments as an extension, as that may change
16228 the meaning of a conforming program. Consider:
16230 struct Dense { static const unsigned int dim = 1; };
16232 template <template <typename> class View,
16234 void operator+(float, View<Block> const&);
16236 template <typename Block,
16237 unsigned int Dim = Block::dim>
16238 struct Lvalue_proxy { operator float() const; };
16242 Lvalue_proxy<Dense> p;
16247 Here, if Lvalue_proxy is permitted to bind to View, then
16248 the global operator+ will be used; if they are not, the
16249 Lvalue_proxy will be converted to float. */
16250 if (coerce_template_parms (parm_parms,
16252 TYPE_TI_TEMPLATE (parm),
16254 ? tf_warning_or_error
16256 /*require_all_args=*/true,
16257 /*use_default_args=*/false)
16258 == error_mark_node)
16261 /* Deduce arguments T, i from TT<T> or TT<i>.
16262 We check each element of PARMVEC and ARGVEC individually
16263 rather than the whole TREE_VEC since they can have
16264 different number of elements. */
16266 parmvec = expand_template_argument_pack (parmvec);
16267 argvec = expand_template_argument_pack (argvec);
16269 len = TREE_VEC_LENGTH (parmvec);
16271 /* Check if the parameters end in a pack, making them
16274 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16275 parm_variadic_p = 1;
16277 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16278 return unify_too_few_arguments (explain_p,
16279 TREE_VEC_LENGTH (argvec), len);
16281 for (i = 0; i < len - parm_variadic_p; ++i)
16283 RECUR_AND_CHECK_FAILURE (tparms, targs,
16284 TREE_VEC_ELT (parmvec, i),
16285 TREE_VEC_ELT (argvec, i),
16286 UNIFY_ALLOW_NONE, explain_p);
16289 if (parm_variadic_p
16290 && unify_pack_expansion (tparms, targs,
16293 /*subr=*/true, explain_p))
16296 arg = TYPE_TI_TEMPLATE (arg);
16298 /* Fall through to deduce template name. */
16301 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16302 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16304 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16306 /* Simple cases: Value already set, does match or doesn't. */
16307 if (targ != NULL_TREE && template_args_equal (targ, arg))
16308 return unify_success (explain_p);
16310 return unify_inconsistency (explain_p, parm, targ, arg);
16314 /* If PARM is `const T' and ARG is only `int', we don't have
16315 a match unless we are allowing additional qualification.
16316 If ARG is `const int' and PARM is just `T' that's OK;
16317 that binds `const int' to `T'. */
16318 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16320 return unify_cv_qual_mismatch (explain_p, parm, arg);
16322 /* Consider the case where ARG is `const volatile int' and
16323 PARM is `const T'. Then, T should be `volatile int'. */
16324 arg = cp_build_qualified_type_real
16325 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16326 if (arg == error_mark_node)
16327 return unify_invalid (explain_p);
16329 /* Simple cases: Value already set, does match or doesn't. */
16330 if (targ != NULL_TREE && same_type_p (targ, arg))
16331 return unify_success (explain_p);
16333 return unify_inconsistency (explain_p, parm, targ, arg);
16335 /* Make sure that ARG is not a variable-sized array. (Note
16336 that were talking about variable-sized arrays (like
16337 `int[n]'), rather than arrays of unknown size (like
16338 `int[]').) We'll get very confused by such a type since
16339 the bound of the array is not constant, and therefore
16340 not mangleable. Besides, such types are not allowed in
16341 ISO C++, so we can do as we please here. We do allow
16342 them for 'auto' deduction, since that isn't ABI-exposed. */
16343 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16344 return unify_vla_arg (explain_p, arg);
16346 /* Strip typedefs as in convert_template_argument. */
16347 arg = canonicalize_type_argument (arg, tf_none);
16350 /* If ARG is a parameter pack or an expansion, we cannot unify
16351 against it unless PARM is also a parameter pack. */
16352 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16353 && !template_parameter_pack_p (parm))
16354 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16356 /* If the argument deduction results is a METHOD_TYPE,
16357 then there is a problem.
16358 METHOD_TYPE doesn't map to any real C++ type the result of
16359 the deduction can not be of that type. */
16360 if (TREE_CODE (arg) == METHOD_TYPE)
16361 return unify_method_type_error (explain_p, arg);
16363 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16364 return unify_success (explain_p);
16366 case TEMPLATE_PARM_INDEX:
16367 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16368 if (tparm == error_mark_node)
16369 return unify_invalid (explain_p);
16371 if (TEMPLATE_PARM_LEVEL (parm)
16372 != template_decl_level (tparm))
16374 /* The PARM is not one we're trying to unify. Just check
16375 to see if it matches ARG. */
16376 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16377 && cp_tree_equal (parm, arg));
16379 unify_expression_unequal (explain_p, parm, arg);
16383 idx = TEMPLATE_PARM_IDX (parm);
16384 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16388 int x = !cp_tree_equal (targ, arg);
16390 unify_inconsistency (explain_p, parm, targ, arg);
16394 /* [temp.deduct.type] If, in the declaration of a function template
16395 with a non-type template-parameter, the non-type
16396 template-parameter is used in an expression in the function
16397 parameter-list and, if the corresponding template-argument is
16398 deduced, the template-argument type shall match the type of the
16399 template-parameter exactly, except that a template-argument
16400 deduced from an array bound may be of any integral type.
16401 The non-type parameter might use already deduced type parameters. */
16402 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16403 if (!TREE_TYPE (arg))
16404 /* Template-parameter dependent expression. Just accept it for now.
16405 It will later be processed in convert_template_argument. */
16407 else if (same_type_p (TREE_TYPE (arg), tparm))
16409 else if ((strict & UNIFY_ALLOW_INTEGER)
16410 && (TREE_CODE (tparm) == INTEGER_TYPE
16411 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16412 /* Convert the ARG to the type of PARM; the deduced non-type
16413 template argument must exactly match the types of the
16414 corresponding parameter. */
16415 arg = fold (build_nop (tparm, arg));
16416 else if (uses_template_parms (tparm))
16417 /* We haven't deduced the type of this parameter yet. Try again
16419 return unify_success (explain_p);
16421 return unify_type_mismatch (explain_p, tparm, arg);
16423 /* If ARG is a parameter pack or an expansion, we cannot unify
16424 against it unless PARM is also a parameter pack. */
16425 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16426 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16427 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16429 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16430 return unify_success (explain_p);
16434 /* A pointer-to-member constant can be unified only with
16435 another constant. */
16436 if (TREE_CODE (arg) != PTRMEM_CST)
16437 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16439 /* Just unify the class member. It would be useless (and possibly
16440 wrong, depending on the strict flags) to unify also
16441 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16442 arg refer to the same variable, even if through different
16443 classes. For instance:
16445 struct A { int x; };
16448 Unification of &A::x and &B::x must succeed. */
16449 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16450 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16455 if (TREE_CODE (arg) != POINTER_TYPE)
16456 return unify_type_mismatch (explain_p, parm, arg);
16458 /* [temp.deduct.call]
16460 A can be another pointer or pointer to member type that can
16461 be converted to the deduced A via a qualification
16462 conversion (_conv.qual_).
16464 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16465 This will allow for additional cv-qualification of the
16466 pointed-to types if appropriate. */
16468 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16469 /* The derived-to-base conversion only persists through one
16470 level of pointers. */
16471 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16473 return unify (tparms, targs, TREE_TYPE (parm),
16474 TREE_TYPE (arg), strict, explain_p);
16477 case REFERENCE_TYPE:
16478 if (TREE_CODE (arg) != REFERENCE_TYPE)
16479 return unify_type_mismatch (explain_p, parm, arg);
16480 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16481 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16484 if (TREE_CODE (arg) != ARRAY_TYPE)
16485 return unify_type_mismatch (explain_p, parm, arg);
16486 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16487 != (TYPE_DOMAIN (arg) == NULL_TREE))
16488 return unify_type_mismatch (explain_p, parm, arg);
16489 if (TYPE_DOMAIN (parm) != NULL_TREE)
16496 /* Our representation of array types uses "N - 1" as the
16497 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16498 not an integer constant. We cannot unify arbitrarily
16499 complex expressions, so we eliminate the MINUS_EXPRs
16501 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16502 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16505 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16506 parm_max = TREE_OPERAND (parm_max, 0);
16508 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16509 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16512 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16513 trying to unify the type of a variable with the type
16514 of a template parameter. For example:
16516 template <unsigned int N>
16517 void f (char (&) [N]);
16524 Here, the type of the ARG will be "int [g(i)]", and
16525 may be a SAVE_EXPR, etc. */
16526 if (TREE_CODE (arg_max) != MINUS_EXPR)
16527 return unify_vla_arg (explain_p, arg);
16528 arg_max = TREE_OPERAND (arg_max, 0);
16531 /* If only one of the bounds used a MINUS_EXPR, compensate
16532 by adding one to the other bound. */
16533 if (parm_cst && !arg_cst)
16534 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16538 else if (arg_cst && !parm_cst)
16539 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16544 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16545 UNIFY_ALLOW_INTEGER, explain_p);
16547 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16548 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16555 case ENUMERAL_TYPE:
16557 if (TREE_CODE (arg) != TREE_CODE (parm))
16558 return unify_type_mismatch (explain_p, parm, arg);
16560 /* We have already checked cv-qualification at the top of the
16562 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16563 return unify_type_mismatch (explain_p, parm, arg);
16565 /* As far as unification is concerned, this wins. Later checks
16566 will invalidate it if necessary. */
16567 return unify_success (explain_p);
16569 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16570 /* Type INTEGER_CST can come from ordinary constant template args. */
16572 while (TREE_CODE (arg) == NOP_EXPR)
16573 arg = TREE_OPERAND (arg, 0);
16575 if (TREE_CODE (arg) != INTEGER_CST)
16576 return unify_template_argument_mismatch (explain_p, parm, arg);
16577 return (tree_int_cst_equal (parm, arg)
16578 ? unify_success (explain_p)
16579 : unify_template_argument_mismatch (explain_p, parm, arg));
16583 int i, len, argslen;
16584 int parm_variadic_p = 0;
16586 if (TREE_CODE (arg) != TREE_VEC)
16587 return unify_template_argument_mismatch (explain_p, parm, arg);
16589 len = TREE_VEC_LENGTH (parm);
16590 argslen = TREE_VEC_LENGTH (arg);
16592 /* Check for pack expansions in the parameters. */
16593 for (i = 0; i < len; ++i)
16595 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16598 /* We can unify against something with a trailing
16600 parm_variadic_p = 1;
16602 /* [temp.deduct.type]/9: If the template argument list of
16603 P contains a pack expansion that is not the last
16604 template argument, the entire template argument list
16605 is a non-deduced context. */
16606 return unify_success (explain_p);
16610 /* If we don't have enough arguments to satisfy the parameters
16611 (not counting the pack expression at the end), or we have
16612 too many arguments for a parameter list that doesn't end in
16613 a pack expression, we can't unify. */
16614 if (parm_variadic_p
16615 ? argslen < len - parm_variadic_p
16617 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16619 /* Unify all of the parameters that precede the (optional)
16620 pack expression. */
16621 for (i = 0; i < len - parm_variadic_p; ++i)
16623 RECUR_AND_CHECK_FAILURE (tparms, targs,
16624 TREE_VEC_ELT (parm, i),
16625 TREE_VEC_ELT (arg, i),
16626 UNIFY_ALLOW_NONE, explain_p);
16628 if (parm_variadic_p)
16629 return unify_pack_expansion (tparms, targs, parm, arg,
16631 /*subr=*/true, explain_p);
16632 return unify_success (explain_p);
16637 if (TREE_CODE (arg) != TREE_CODE (parm))
16638 return unify_type_mismatch (explain_p, parm, arg);
16640 if (TYPE_PTRMEMFUNC_P (parm))
16642 if (!TYPE_PTRMEMFUNC_P (arg))
16643 return unify_type_mismatch (explain_p, parm, arg);
16645 return unify (tparms, targs,
16646 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16647 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16648 strict, explain_p);
16651 if (CLASSTYPE_TEMPLATE_INFO (parm))
16653 tree t = NULL_TREE;
16655 if (strict_in & UNIFY_ALLOW_DERIVED)
16657 /* First, we try to unify the PARM and ARG directly. */
16658 t = try_class_unification (tparms, targs,
16659 parm, arg, explain_p);
16663 /* Fallback to the special case allowed in
16664 [temp.deduct.call]:
16666 If P is a class, and P has the form
16667 template-id, then A can be a derived class of
16668 the deduced A. Likewise, if P is a pointer to
16669 a class of the form template-id, A can be a
16670 pointer to a derived class pointed to by the
16672 enum template_base_result r;
16673 r = get_template_base (tparms, targs, parm, arg,
16677 return unify_no_common_base (explain_p, r, parm, arg);
16680 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16681 && (CLASSTYPE_TI_TEMPLATE (parm)
16682 == CLASSTYPE_TI_TEMPLATE (arg)))
16683 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16684 Then, we should unify `int' and `U'. */
16687 /* There's no chance of unification succeeding. */
16688 return unify_type_mismatch (explain_p, parm, arg);
16690 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16691 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16693 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16694 return unify_type_mismatch (explain_p, parm, arg);
16695 return unify_success (explain_p);
16698 case FUNCTION_TYPE:
16700 unsigned int nargs;
16705 if (TREE_CODE (arg) != TREE_CODE (parm))
16706 return unify_type_mismatch (explain_p, parm, arg);
16708 /* CV qualifications for methods can never be deduced, they must
16709 match exactly. We need to check them explicitly here,
16710 because type_unification_real treats them as any other
16711 cv-qualified parameter. */
16712 if (TREE_CODE (parm) == METHOD_TYPE
16713 && (!check_cv_quals_for_unify
16715 class_of_this_parm (arg),
16716 class_of_this_parm (parm))))
16717 return unify_cv_qual_mismatch (explain_p, parm, arg);
16719 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16720 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16722 nargs = list_length (TYPE_ARG_TYPES (arg));
16723 args = XALLOCAVEC (tree, nargs);
16724 for (a = TYPE_ARG_TYPES (arg), i = 0;
16725 a != NULL_TREE && a != void_list_node;
16726 a = TREE_CHAIN (a), ++i)
16727 args[i] = TREE_VALUE (a);
16730 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16731 args, nargs, 1, DEDUCE_EXACT,
16732 LOOKUP_NORMAL, explain_p);
16736 /* Unify a pointer to member with a pointer to member function, which
16737 deduces the type of the member as a function type. */
16738 if (TYPE_PTRMEMFUNC_P (arg))
16743 /* Check top-level cv qualifiers */
16744 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16745 return unify_cv_qual_mismatch (explain_p, parm, arg);
16747 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16748 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16749 UNIFY_ALLOW_NONE, explain_p);
16751 /* Determine the type of the function we are unifying against. */
16752 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16754 build_function_type (TREE_TYPE (method_type),
16755 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16757 /* Extract the cv-qualifiers of the member function from the
16758 implicit object parameter and place them on the function
16759 type to be restored later. */
16760 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16761 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16764 if (TREE_CODE (arg) != OFFSET_TYPE)
16765 return unify_type_mismatch (explain_p, parm, arg);
16766 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16767 TYPE_OFFSET_BASETYPE (arg),
16768 UNIFY_ALLOW_NONE, explain_p);
16769 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16770 strict, explain_p);
16773 if (DECL_TEMPLATE_PARM_P (parm))
16774 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16775 if (arg != integral_constant_value (parm))
16776 return unify_template_argument_mismatch (explain_p, parm, arg);
16777 return unify_success (explain_p);
16780 case TEMPLATE_DECL:
16781 /* Matched cases are handled by the ARG == PARM test above. */
16782 return unify_template_argument_mismatch (explain_p, parm, arg);
16785 /* A non-type template parameter that is a variable should be a
16786 an integral constant, in which case, it whould have been
16787 folded into its (constant) value. So we should not be getting
16788 a variable here. */
16789 gcc_unreachable ();
16791 case TYPE_ARGUMENT_PACK:
16792 case NONTYPE_ARGUMENT_PACK:
16793 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16794 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16797 case DECLTYPE_TYPE:
16798 case UNDERLYING_TYPE:
16799 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16800 or UNDERLYING_TYPE nodes. */
16801 return unify_success (explain_p);
16804 /* Unification fails if we hit an error node. */
16805 return unify_invalid (explain_p);
16808 /* An unresolved overload is a nondeduced context. */
16809 if (type_unknown_p (parm))
16810 return unify_success (explain_p);
16811 gcc_assert (EXPR_P (parm));
16813 /* We must be looking at an expression. This can happen with
16817 void foo(S<I>, S<I + 2>);
16819 This is a "nondeduced context":
16823 The nondeduced contexts are:
16825 --A type that is a template-id in which one or more of
16826 the template-arguments is an expression that references
16827 a template-parameter.
16829 In these cases, we assume deduction succeeded, but don't
16830 actually infer any unifications. */
16832 if (!uses_template_parms (parm)
16833 && !template_args_equal (parm, arg))
16834 return unify_expression_unequal (explain_p, parm, arg);
16836 return unify_success (explain_p);
16839 #undef RECUR_AND_CHECK_FAILURE
16841 /* Note that DECL can be defined in this translation unit, if
16845 mark_definable (tree decl)
16848 DECL_NOT_REALLY_EXTERN (decl) = 1;
16849 FOR_EACH_CLONE (clone, decl)
16850 DECL_NOT_REALLY_EXTERN (clone) = 1;
16853 /* Called if RESULT is explicitly instantiated, or is a member of an
16854 explicitly instantiated class. */
16857 mark_decl_instantiated (tree result, int extern_p)
16859 SET_DECL_EXPLICIT_INSTANTIATION (result);
16861 /* If this entity has already been written out, it's too late to
16862 make any modifications. */
16863 if (TREE_ASM_WRITTEN (result))
16866 if (TREE_CODE (result) != FUNCTION_DECL)
16867 /* The TREE_PUBLIC flag for function declarations will have been
16868 set correctly by tsubst. */
16869 TREE_PUBLIC (result) = 1;
16871 /* This might have been set by an earlier implicit instantiation. */
16872 DECL_COMDAT (result) = 0;
16875 DECL_NOT_REALLY_EXTERN (result) = 0;
16878 mark_definable (result);
16879 /* Always make artificials weak. */
16880 if (DECL_ARTIFICIAL (result) && flag_weak)
16881 comdat_linkage (result);
16882 /* For WIN32 we also want to put explicit instantiations in
16883 linkonce sections. */
16884 else if (TREE_PUBLIC (result))
16885 maybe_make_one_only (result);
16888 /* If EXTERN_P, then this function will not be emitted -- unless
16889 followed by an explicit instantiation, at which point its linkage
16890 will be adjusted. If !EXTERN_P, then this function will be
16891 emitted here. In neither circumstance do we want
16892 import_export_decl to adjust the linkage. */
16893 DECL_INTERFACE_KNOWN (result) = 1;
16896 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16897 important template arguments. If any are missing, we check whether
16898 they're important by using error_mark_node for substituting into any
16899 args that were used for partial ordering (the ones between ARGS and END)
16900 and seeing if it bubbles up. */
16903 check_undeduced_parms (tree targs, tree args, tree end)
16905 bool found = false;
16907 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16908 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16911 TREE_VEC_ELT (targs, i) = error_mark_node;
16915 for (; args != end; args = TREE_CHAIN (args))
16917 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16918 if (substed == error_mark_node)
16925 /* Given two function templates PAT1 and PAT2, return:
16927 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16928 -1 if PAT2 is more specialized than PAT1.
16929 0 if neither is more specialized.
16931 LEN indicates the number of parameters we should consider
16932 (defaulted parameters should not be considered).
16934 The 1998 std underspecified function template partial ordering, and
16935 DR214 addresses the issue. We take pairs of arguments, one from
16936 each of the templates, and deduce them against each other. One of
16937 the templates will be more specialized if all the *other*
16938 template's arguments deduce against its arguments and at least one
16939 of its arguments *does* *not* deduce against the other template's
16940 corresponding argument. Deduction is done as for class templates.
16941 The arguments used in deduction have reference and top level cv
16942 qualifiers removed. Iff both arguments were originally reference
16943 types *and* deduction succeeds in both directions, the template
16944 with the more cv-qualified argument wins for that pairing (if
16945 neither is more cv-qualified, they both are equal). Unlike regular
16946 deduction, after all the arguments have been deduced in this way,
16947 we do *not* verify the deduced template argument values can be
16948 substituted into non-deduced contexts.
16950 The logic can be a bit confusing here, because we look at deduce1 and
16951 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16952 can find template arguments for pat1 to make arg1 look like arg2, that
16953 means that arg2 is at least as specialized as arg1. */
16956 more_specialized_fn (tree pat1, tree pat2, int len)
16958 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16959 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16960 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16961 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16962 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16963 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16964 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16965 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16966 tree origs1, origs2;
16967 bool lose1 = false;
16968 bool lose2 = false;
16970 /* Remove the this parameter from non-static member functions. If
16971 one is a non-static member function and the other is not a static
16972 member function, remove the first parameter from that function
16973 also. This situation occurs for operator functions where we
16974 locate both a member function (with this pointer) and non-member
16975 operator (with explicit first operand). */
16976 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16978 len--; /* LEN is the number of significant arguments for DECL1 */
16979 args1 = TREE_CHAIN (args1);
16980 if (!DECL_STATIC_FUNCTION_P (decl2))
16981 args2 = TREE_CHAIN (args2);
16983 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16985 args2 = TREE_CHAIN (args2);
16986 if (!DECL_STATIC_FUNCTION_P (decl1))
16989 args1 = TREE_CHAIN (args1);
16993 /* If only one is a conversion operator, they are unordered. */
16994 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16997 /* Consider the return type for a conversion function */
16998 if (DECL_CONV_FN_P (decl1))
17000 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17001 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17005 processing_template_decl++;
17011 /* Stop when an ellipsis is seen. */
17012 && args1 != NULL_TREE && args2 != NULL_TREE)
17014 tree arg1 = TREE_VALUE (args1);
17015 tree arg2 = TREE_VALUE (args2);
17016 int deduce1, deduce2;
17020 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17021 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17023 /* When both arguments are pack expansions, we need only
17024 unify the patterns themselves. */
17025 arg1 = PACK_EXPANSION_PATTERN (arg1);
17026 arg2 = PACK_EXPANSION_PATTERN (arg2);
17028 /* This is the last comparison we need to do. */
17032 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17034 arg1 = TREE_TYPE (arg1);
17035 quals1 = cp_type_quals (arg1);
17038 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17040 arg2 = TREE_TYPE (arg2);
17041 quals2 = cp_type_quals (arg2);
17044 if ((quals1 < 0) != (quals2 < 0))
17046 /* Only of the args is a reference, see if we should apply
17047 array/function pointer decay to it. This is not part of
17048 DR214, but is, IMHO, consistent with the deduction rules
17049 for the function call itself, and with our earlier
17050 implementation of the underspecified partial ordering
17051 rules. (nathan). */
17054 switch (TREE_CODE (arg1))
17057 arg1 = TREE_TYPE (arg1);
17059 case FUNCTION_TYPE:
17060 arg1 = build_pointer_type (arg1);
17069 switch (TREE_CODE (arg2))
17072 arg2 = TREE_TYPE (arg2);
17074 case FUNCTION_TYPE:
17075 arg2 = build_pointer_type (arg2);
17084 arg1 = TYPE_MAIN_VARIANT (arg1);
17085 arg2 = TYPE_MAIN_VARIANT (arg2);
17087 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17089 int i, len2 = list_length (args2);
17090 tree parmvec = make_tree_vec (1);
17091 tree argvec = make_tree_vec (len2);
17094 /* Setup the parameter vector, which contains only ARG1. */
17095 TREE_VEC_ELT (parmvec, 0) = arg1;
17097 /* Setup the argument vector, which contains the remaining
17099 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17100 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17102 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17103 argvec, DEDUCE_EXACT,
17104 /*subr=*/true, /*explain_p=*/false)
17107 /* We cannot deduce in the other direction, because ARG1 is
17108 a pack expansion but ARG2 is not. */
17111 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17113 int i, len1 = list_length (args1);
17114 tree parmvec = make_tree_vec (1);
17115 tree argvec = make_tree_vec (len1);
17118 /* Setup the parameter vector, which contains only ARG1. */
17119 TREE_VEC_ELT (parmvec, 0) = arg2;
17121 /* Setup the argument vector, which contains the remaining
17123 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17124 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17126 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17127 argvec, DEDUCE_EXACT,
17128 /*subr=*/true, /*explain_p=*/false)
17131 /* We cannot deduce in the other direction, because ARG2 is
17132 a pack expansion but ARG1 is not.*/
17138 /* The normal case, where neither argument is a pack
17140 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17141 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17143 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17144 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17148 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17149 arg2, then arg2 is not as specialized as arg1. */
17155 /* "If, for a given type, deduction succeeds in both directions
17156 (i.e., the types are identical after the transformations above)
17157 and if the type from the argument template is more cv-qualified
17158 than the type from the parameter template (as described above)
17159 that type is considered to be more specialized than the other. If
17160 neither type is more cv-qualified than the other then neither type
17161 is more specialized than the other." */
17163 if (deduce1 && deduce2
17164 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17166 if ((quals1 & quals2) == quals2)
17168 if ((quals1 & quals2) == quals1)
17172 if (lose1 && lose2)
17173 /* We've failed to deduce something in either direction.
17174 These must be unordered. */
17177 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17178 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17179 /* We have already processed all of the arguments in our
17180 handing of the pack expansion type. */
17183 args1 = TREE_CHAIN (args1);
17184 args2 = TREE_CHAIN (args2);
17187 /* "In most cases, all template parameters must have values in order for
17188 deduction to succeed, but for partial ordering purposes a template
17189 parameter may remain without a value provided it is not used in the
17190 types being used for partial ordering."
17192 Thus, if we are missing any of the targs1 we need to substitute into
17193 origs1, then pat2 is not as specialized as pat1. This can happen when
17194 there is a nondeduced context. */
17195 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17197 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17200 processing_template_decl--;
17202 /* All things being equal, if the next argument is a pack expansion
17203 for one function but not for the other, prefer the
17204 non-variadic function. FIXME this is bogus; see c++/41958. */
17206 && args1 && TREE_VALUE (args1)
17207 && args2 && TREE_VALUE (args2))
17209 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17210 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17213 if (lose1 == lose2)
17221 /* Determine which of two partial specializations is more specialized.
17223 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17224 to the first partial specialization. The TREE_VALUE is the
17225 innermost set of template parameters for the partial
17226 specialization. PAT2 is similar, but for the second template.
17228 Return 1 if the first partial specialization is more specialized;
17229 -1 if the second is more specialized; 0 if neither is more
17232 See [temp.class.order] for information about determining which of
17233 two templates is more specialized. */
17236 more_specialized_class (tree pat1, tree pat2)
17241 bool any_deductions = false;
17243 tmpl1 = TREE_TYPE (pat1);
17244 tmpl2 = TREE_TYPE (pat2);
17246 /* Just like what happens for functions, if we are ordering between
17247 different class template specializations, we may encounter dependent
17248 types in the arguments, and we need our dependency check functions
17249 to behave correctly. */
17250 ++processing_template_decl;
17251 targs = get_class_bindings (TREE_VALUE (pat1),
17252 CLASSTYPE_TI_ARGS (tmpl1),
17253 CLASSTYPE_TI_ARGS (tmpl2));
17257 any_deductions = true;
17260 targs = get_class_bindings (TREE_VALUE (pat2),
17261 CLASSTYPE_TI_ARGS (tmpl2),
17262 CLASSTYPE_TI_ARGS (tmpl1));
17266 any_deductions = true;
17268 --processing_template_decl;
17270 /* In the case of a tie where at least one of the class templates
17271 has a parameter pack at the end, the template with the most
17272 non-packed parameters wins. */
17275 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17276 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17278 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17279 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17280 int len1 = TREE_VEC_LENGTH (args1);
17281 int len2 = TREE_VEC_LENGTH (args2);
17283 /* We don't count the pack expansion at the end. */
17284 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17286 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17291 else if (len1 < len2)
17298 /* Return the template arguments that will produce the function signature
17299 DECL from the function template FN, with the explicit template
17300 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17301 also match. Return NULL_TREE if no satisfactory arguments could be
17305 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17307 int ntparms = DECL_NTPARMS (fn);
17308 tree targs = make_tree_vec (ntparms);
17310 tree decl_arg_types;
17312 unsigned int nargs, ix;
17315 /* Substitute the explicit template arguments into the type of DECL.
17316 The call to fn_type_unification will handle substitution into the
17318 decl_type = TREE_TYPE (decl);
17319 if (explicit_args && uses_template_parms (decl_type))
17322 tree converted_args;
17324 if (DECL_TEMPLATE_INFO (decl))
17325 tmpl = DECL_TI_TEMPLATE (decl);
17327 /* We can get here for some invalid specializations. */
17331 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17332 explicit_args, NULL_TREE,
17334 /*require_all_args=*/false,
17335 /*use_default_args=*/false);
17336 if (converted_args == error_mark_node)
17339 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17340 if (decl_type == error_mark_node)
17344 /* Never do unification on the 'this' parameter. */
17345 decl_arg_types = skip_artificial_parms_for (decl,
17346 TYPE_ARG_TYPES (decl_type));
17348 nargs = list_length (decl_arg_types);
17349 args = XALLOCAVEC (tree, nargs);
17350 for (arg = decl_arg_types, ix = 0;
17351 arg != NULL_TREE && arg != void_list_node;
17352 arg = TREE_CHAIN (arg), ++ix)
17353 args[ix] = TREE_VALUE (arg);
17355 if (fn_type_unification (fn, explicit_args, targs,
17357 (check_rettype || DECL_CONV_FN_P (fn)
17358 ? TREE_TYPE (decl_type) : NULL_TREE),
17359 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17365 /* Return the innermost template arguments that, when applied to a
17366 template specialization whose innermost template parameters are
17367 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17370 For example, suppose we have:
17372 template <class T, class U> struct S {};
17373 template <class T> struct S<T*, int> {};
17375 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17376 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17377 int}. The resulting vector will be {double}, indicating that `T'
17378 is bound to `double'. */
17381 get_class_bindings (tree tparms, tree spec_args, tree args)
17383 int i, ntparms = TREE_VEC_LENGTH (tparms);
17385 tree innermost_deduced_args;
17387 innermost_deduced_args = make_tree_vec (ntparms);
17388 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17390 deduced_args = copy_node (args);
17391 SET_TMPL_ARGS_LEVEL (deduced_args,
17392 TMPL_ARGS_DEPTH (deduced_args),
17393 innermost_deduced_args);
17396 deduced_args = innermost_deduced_args;
17398 if (unify (tparms, deduced_args,
17399 INNERMOST_TEMPLATE_ARGS (spec_args),
17400 INNERMOST_TEMPLATE_ARGS (args),
17401 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17404 for (i = 0; i < ntparms; ++i)
17405 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17408 /* Verify that nondeduced template arguments agree with the type
17409 obtained from argument deduction.
17413 struct A { typedef int X; };
17414 template <class T, class U> struct C {};
17415 template <class T> struct C<T, typename T::X> {};
17417 Then with the instantiation `C<A, int>', we can deduce that
17418 `T' is `A' but unify () does not check whether `typename T::X'
17420 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17421 if (spec_args == error_mark_node
17422 /* We only need to check the innermost arguments; the other
17423 arguments will always agree. */
17424 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17425 INNERMOST_TEMPLATE_ARGS (args)))
17428 /* Now that we have bindings for all of the template arguments,
17429 ensure that the arguments deduced for the template template
17430 parameters have compatible template parameter lists. See the use
17431 of template_template_parm_bindings_ok_p in fn_type_unification
17432 for more information. */
17433 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17436 return deduced_args;
17439 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17440 Return the TREE_LIST node with the most specialized template, if
17441 any. If there is no most specialized template, the error_mark_node
17444 Note that this function does not look at, or modify, the
17445 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17446 returned is one of the elements of INSTANTIATIONS, callers may
17447 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17448 and retrieve it from the value returned. */
17451 most_specialized_instantiation (tree templates)
17455 ++processing_template_decl;
17458 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17462 if (get_bindings (TREE_VALUE (champ),
17463 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17464 NULL_TREE, /*check_ret=*/true))
17467 if (get_bindings (TREE_VALUE (fn),
17468 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17469 NULL_TREE, /*check_ret=*/true))
17476 /* Equally specialized, move to next function. If there
17477 is no next function, nothing's most specialized. */
17478 fn = TREE_CHAIN (fn);
17486 /* Now verify that champ is better than everything earlier in the
17487 instantiation list. */
17488 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17489 if (get_bindings (TREE_VALUE (champ),
17490 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17491 NULL_TREE, /*check_ret=*/true)
17492 || !get_bindings (TREE_VALUE (fn),
17493 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17494 NULL_TREE, /*check_ret=*/true))
17500 processing_template_decl--;
17503 return error_mark_node;
17508 /* If DECL is a specialization of some template, return the most
17509 general such template. Otherwise, returns NULL_TREE.
17511 For example, given:
17513 template <class T> struct S { template <class U> void f(U); };
17515 if TMPL is `template <class U> void S<int>::f(U)' this will return
17516 the full template. This function will not trace past partial
17517 specializations, however. For example, given in addition:
17519 template <class T> struct S<T*> { template <class U> void f(U); };
17521 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17522 `template <class T> template <class U> S<T*>::f(U)'. */
17525 most_general_template (tree decl)
17527 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17528 an immediate specialization. */
17529 if (TREE_CODE (decl) == FUNCTION_DECL)
17531 if (DECL_TEMPLATE_INFO (decl)) {
17532 decl = DECL_TI_TEMPLATE (decl);
17534 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17535 template friend. */
17536 if (TREE_CODE (decl) != TEMPLATE_DECL)
17542 /* Look for more and more general templates. */
17543 while (DECL_TEMPLATE_INFO (decl))
17545 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17546 (See cp-tree.h for details.) */
17547 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17550 if (CLASS_TYPE_P (TREE_TYPE (decl))
17551 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17554 /* Stop if we run into an explicitly specialized class template. */
17555 if (!DECL_NAMESPACE_SCOPE_P (decl)
17556 && DECL_CONTEXT (decl)
17557 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17560 decl = DECL_TI_TEMPLATE (decl);
17566 /* Return the most specialized of the class template partial
17567 specializations of TMPL which can produce TYPE, a specialization of
17568 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17569 a _TYPE node corresponding to the partial specialization, while the
17570 TREE_PURPOSE is the set of template arguments that must be
17571 substituted into the TREE_TYPE in order to generate TYPE.
17573 If the choice of partial specialization is ambiguous, a diagnostic
17574 is issued, and the error_mark_node is returned. If there are no
17575 partial specializations of TMPL matching TYPE, then NULL_TREE is
17579 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17581 tree list = NULL_TREE;
17587 tree outer_args = NULL_TREE;
17589 tmpl = most_general_template (tmpl);
17590 args = CLASSTYPE_TI_ARGS (type);
17592 /* For determining which partial specialization to use, only the
17593 innermost args are interesting. */
17594 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17596 outer_args = strip_innermost_template_args (args, 1);
17597 args = INNERMOST_TEMPLATE_ARGS (args);
17600 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17602 tree partial_spec_args;
17604 tree parms = TREE_VALUE (t);
17606 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17608 ++processing_template_decl;
17614 /* Discard the outer levels of args, and then substitute in the
17615 template args from the enclosing class. */
17616 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17617 partial_spec_args = tsubst_template_args
17618 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17620 /* PARMS already refers to just the innermost parms, but the
17621 template parms in partial_spec_args had their levels lowered
17622 by tsubst, so we need to do the same for the parm list. We
17623 can't just tsubst the TREE_VEC itself, as tsubst wants to
17624 treat a TREE_VEC as an argument vector. */
17625 parms = copy_node (parms);
17626 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17627 TREE_VEC_ELT (parms, i) =
17628 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17632 partial_spec_args =
17633 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17634 add_to_template_args (outer_args,
17635 partial_spec_args),
17637 /*require_all_args=*/true,
17638 /*use_default_args=*/true);
17640 --processing_template_decl;
17642 if (partial_spec_args == error_mark_node)
17643 return error_mark_node;
17645 spec_args = get_class_bindings (parms,
17651 spec_args = add_to_template_args (outer_args, spec_args);
17652 list = tree_cons (spec_args, TREE_VALUE (t), list);
17653 TREE_TYPE (list) = TREE_TYPE (t);
17660 ambiguous_p = false;
17663 t = TREE_CHAIN (t);
17664 for (; t; t = TREE_CHAIN (t))
17666 fate = more_specialized_class (champ, t);
17673 t = TREE_CHAIN (t);
17676 ambiguous_p = true;
17685 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17687 fate = more_specialized_class (champ, t);
17690 ambiguous_p = true;
17698 char *spaces = NULL;
17699 if (!(complain & tf_error))
17700 return error_mark_node;
17701 error ("ambiguous class template instantiation for %q#T", type);
17702 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17703 for (t = list; t; t = TREE_CHAIN (t))
17705 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17706 spaces = spaces ? spaces : get_spaces (str);
17709 return error_mark_node;
17715 /* Explicitly instantiate DECL. */
17718 do_decl_instantiation (tree decl, tree storage)
17720 tree result = NULL_TREE;
17723 if (!decl || decl == error_mark_node)
17724 /* An error occurred, for which grokdeclarator has already issued
17725 an appropriate message. */
17727 else if (! DECL_LANG_SPECIFIC (decl))
17729 error ("explicit instantiation of non-template %q#D", decl);
17732 else if (TREE_CODE (decl) == VAR_DECL)
17734 /* There is an asymmetry here in the way VAR_DECLs and
17735 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17736 the latter, the DECL we get back will be marked as a
17737 template instantiation, and the appropriate
17738 DECL_TEMPLATE_INFO will be set up. This does not happen for
17739 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17740 should handle VAR_DECLs as it currently handles
17742 if (!DECL_CLASS_SCOPE_P (decl))
17744 error ("%qD is not a static data member of a class template", decl);
17747 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17748 if (!result || TREE_CODE (result) != VAR_DECL)
17750 error ("no matching template for %qD found", decl);
17753 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17755 error ("type %qT for explicit instantiation %qD does not match "
17756 "declared type %qT", TREE_TYPE (result), decl,
17761 else if (TREE_CODE (decl) != FUNCTION_DECL)
17763 error ("explicit instantiation of %q#D", decl);
17769 /* Check for various error cases. Note that if the explicit
17770 instantiation is valid the RESULT will currently be marked as an
17771 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17772 until we get here. */
17774 if (DECL_TEMPLATE_SPECIALIZATION (result))
17776 /* DR 259 [temp.spec].
17778 Both an explicit instantiation and a declaration of an explicit
17779 specialization shall not appear in a program unless the explicit
17780 instantiation follows a declaration of the explicit specialization.
17782 For a given set of template parameters, if an explicit
17783 instantiation of a template appears after a declaration of an
17784 explicit specialization for that template, the explicit
17785 instantiation has no effect. */
17788 else if (DECL_EXPLICIT_INSTANTIATION (result))
17792 No program shall explicitly instantiate any template more
17795 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17796 the first instantiation was `extern' and the second is not,
17797 and EXTERN_P for the opposite case. */
17798 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17799 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17800 /* If an "extern" explicit instantiation follows an ordinary
17801 explicit instantiation, the template is instantiated. */
17805 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17807 error ("no matching template for %qD found", result);
17810 else if (!DECL_TEMPLATE_INFO (result))
17812 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17816 if (storage == NULL_TREE)
17818 else if (storage == ridpointers[(int) RID_EXTERN])
17820 if (!in_system_header && (cxx_dialect == cxx98))
17821 pedwarn (input_location, OPT_pedantic,
17822 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17827 error ("storage class %qD applied to template instantiation", storage);
17829 check_explicit_instantiation_namespace (result);
17830 mark_decl_instantiated (result, extern_p);
17832 instantiate_decl (result, /*defer_ok=*/1,
17833 /*expl_inst_class_mem_p=*/false);
17837 mark_class_instantiated (tree t, int extern_p)
17839 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17840 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17841 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17842 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17845 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17846 rest_of_type_compilation (t, 1);
17850 /* Called from do_type_instantiation through binding_table_foreach to
17851 do recursive instantiation for the type bound in ENTRY. */
17853 bt_instantiate_type_proc (binding_entry entry, void *data)
17855 tree storage = *(tree *) data;
17857 if (MAYBE_CLASS_TYPE_P (entry->type)
17858 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17859 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17862 /* Called from do_type_instantiation to instantiate a member
17863 (a member function or a static member variable) of an
17864 explicitly instantiated class template. */
17866 instantiate_class_member (tree decl, int extern_p)
17868 mark_decl_instantiated (decl, extern_p);
17870 instantiate_decl (decl, /*defer_ok=*/1,
17871 /*expl_inst_class_mem_p=*/true);
17874 /* Perform an explicit instantiation of template class T. STORAGE, if
17875 non-null, is the RID for extern, inline or static. COMPLAIN is
17876 nonzero if this is called from the parser, zero if called recursively,
17877 since the standard is unclear (as detailed below). */
17880 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17885 int previous_instantiation_extern_p = 0;
17887 if (TREE_CODE (t) == TYPE_DECL)
17890 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17893 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
17895 error ("explicit instantiation of non-class template %qD", tmpl);
17897 error ("explicit instantiation of non-template type %qT", t);
17903 if (!COMPLETE_TYPE_P (t))
17905 if (complain & tf_error)
17906 error ("explicit instantiation of %q#T before definition of template",
17911 if (storage != NULL_TREE)
17913 if (!in_system_header)
17915 if (storage == ridpointers[(int) RID_EXTERN])
17917 if (cxx_dialect == cxx98)
17918 pedwarn (input_location, OPT_pedantic,
17919 "ISO C++ 1998 forbids the use of %<extern%> on "
17920 "explicit instantiations");
17923 pedwarn (input_location, OPT_pedantic,
17924 "ISO C++ forbids the use of %qE"
17925 " on explicit instantiations", storage);
17928 if (storage == ridpointers[(int) RID_INLINE])
17930 else if (storage == ridpointers[(int) RID_EXTERN])
17932 else if (storage == ridpointers[(int) RID_STATIC])
17936 error ("storage class %qD applied to template instantiation",
17942 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17944 /* DR 259 [temp.spec].
17946 Both an explicit instantiation and a declaration of an explicit
17947 specialization shall not appear in a program unless the explicit
17948 instantiation follows a declaration of the explicit specialization.
17950 For a given set of template parameters, if an explicit
17951 instantiation of a template appears after a declaration of an
17952 explicit specialization for that template, the explicit
17953 instantiation has no effect. */
17956 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17960 No program shall explicitly instantiate any template more
17963 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17964 instantiation was `extern'. If EXTERN_P then the second is.
17965 These cases are OK. */
17966 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17968 if (!previous_instantiation_extern_p && !extern_p
17969 && (complain & tf_error))
17970 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17972 /* If we've already instantiated the template, just return now. */
17973 if (!CLASSTYPE_INTERFACE_ONLY (t))
17977 check_explicit_instantiation_namespace (TYPE_NAME (t));
17978 mark_class_instantiated (t, extern_p);
17986 /* In contrast to implicit instantiation, where only the
17987 declarations, and not the definitions, of members are
17988 instantiated, we have here:
17992 The explicit instantiation of a class template specialization
17993 implies the instantiation of all of its members not
17994 previously explicitly specialized in the translation unit
17995 containing the explicit instantiation.
17997 Of course, we can't instantiate member template classes, since
17998 we don't have any arguments for them. Note that the standard
17999 is unclear on whether the instantiation of the members are
18000 *explicit* instantiations or not. However, the most natural
18001 interpretation is that it should be an explicit instantiation. */
18004 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18005 if (TREE_CODE (tmp) == FUNCTION_DECL
18006 && DECL_TEMPLATE_INSTANTIATION (tmp))
18007 instantiate_class_member (tmp, extern_p);
18009 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18010 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18011 instantiate_class_member (tmp, extern_p);
18013 if (CLASSTYPE_NESTED_UTDS (t))
18014 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18015 bt_instantiate_type_proc, &storage);
18019 /* Given a function DECL, which is a specialization of TMPL, modify
18020 DECL to be a re-instantiation of TMPL with the same template
18021 arguments. TMPL should be the template into which tsubst'ing
18022 should occur for DECL, not the most general template.
18024 One reason for doing this is a scenario like this:
18027 void f(const T&, int i);
18029 void g() { f(3, 7); }
18032 void f(const T& t, const int i) { }
18034 Note that when the template is first instantiated, with
18035 instantiate_template, the resulting DECL will have no name for the
18036 first parameter, and the wrong type for the second. So, when we go
18037 to instantiate the DECL, we regenerate it. */
18040 regenerate_decl_from_template (tree decl, tree tmpl)
18042 /* The arguments used to instantiate DECL, from the most general
18047 args = DECL_TI_ARGS (decl);
18048 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18050 /* Make sure that we can see identifiers, and compute access
18052 push_access_scope (decl);
18054 if (TREE_CODE (decl) == FUNCTION_DECL)
18062 args_depth = TMPL_ARGS_DEPTH (args);
18063 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18064 if (args_depth > parms_depth)
18065 args = get_innermost_template_args (args, parms_depth);
18067 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18068 args, tf_error, NULL_TREE,
18069 /*defer_ok*/false);
18070 if (specs && specs != error_mark_node)
18071 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18074 /* Merge parameter declarations. */
18075 decl_parm = skip_artificial_parms_for (decl,
18076 DECL_ARGUMENTS (decl));
18078 = skip_artificial_parms_for (code_pattern,
18079 DECL_ARGUMENTS (code_pattern));
18080 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18085 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18086 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18087 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18089 parm_type = type_decays_to (parm_type);
18090 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18091 TREE_TYPE (decl_parm) = parm_type;
18092 attributes = DECL_ATTRIBUTES (pattern_parm);
18093 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18095 DECL_ATTRIBUTES (decl_parm) = attributes;
18096 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18098 decl_parm = DECL_CHAIN (decl_parm);
18099 pattern_parm = DECL_CHAIN (pattern_parm);
18101 /* Merge any parameters that match with the function parameter
18103 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18106 tree expanded_types;
18107 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18108 the parameters in this function parameter pack. */
18109 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18110 args, tf_error, NULL_TREE);
18111 len = TREE_VEC_LENGTH (expanded_types);
18112 for (i = 0; i < len; i++)
18117 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18118 /* Rename the parameter to include the index. */
18119 DECL_NAME (decl_parm) =
18120 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18121 parm_type = TREE_VEC_ELT (expanded_types, i);
18122 parm_type = type_decays_to (parm_type);
18123 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18124 TREE_TYPE (decl_parm) = parm_type;
18125 attributes = DECL_ATTRIBUTES (pattern_parm);
18126 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18128 DECL_ATTRIBUTES (decl_parm) = attributes;
18129 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18131 decl_parm = DECL_CHAIN (decl_parm);
18134 /* Merge additional specifiers from the CODE_PATTERN. */
18135 if (DECL_DECLARED_INLINE_P (code_pattern)
18136 && !DECL_DECLARED_INLINE_P (decl))
18137 DECL_DECLARED_INLINE_P (decl) = 1;
18139 else if (TREE_CODE (decl) == VAR_DECL)
18141 DECL_INITIAL (decl) =
18142 tsubst_expr (DECL_INITIAL (code_pattern), args,
18143 tf_error, DECL_TI_TEMPLATE (decl),
18144 /*integral_constant_expression_p=*/false);
18145 if (VAR_HAD_UNKNOWN_BOUND (decl))
18146 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18147 tf_error, DECL_TI_TEMPLATE (decl));
18150 gcc_unreachable ();
18152 pop_access_scope (decl);
18155 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18156 substituted to get DECL. */
18159 template_for_substitution (tree decl)
18161 tree tmpl = DECL_TI_TEMPLATE (decl);
18163 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18164 for the instantiation. This is not always the most general
18165 template. Consider, for example:
18168 struct S { template <class U> void f();
18169 template <> void f<int>(); };
18171 and an instantiation of S<double>::f<int>. We want TD to be the
18172 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18173 while (/* An instantiation cannot have a definition, so we need a
18174 more general template. */
18175 DECL_TEMPLATE_INSTANTIATION (tmpl)
18176 /* We must also deal with friend templates. Given:
18178 template <class T> struct S {
18179 template <class U> friend void f() {};
18182 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18183 so far as the language is concerned, but that's still
18184 where we get the pattern for the instantiation from. On
18185 other hand, if the definition comes outside the class, say:
18187 template <class T> struct S {
18188 template <class U> friend void f();
18190 template <class U> friend void f() {}
18192 we don't need to look any further. That's what the check for
18193 DECL_INITIAL is for. */
18194 || (TREE_CODE (decl) == FUNCTION_DECL
18195 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18196 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18198 /* The present template, TD, should not be a definition. If it
18199 were a definition, we should be using it! Note that we
18200 cannot restructure the loop to just keep going until we find
18201 a template with a definition, since that might go too far if
18202 a specialization was declared, but not defined. */
18203 gcc_assert (TREE_CODE (decl) != VAR_DECL
18204 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18206 /* Fetch the more general template. */
18207 tmpl = DECL_TI_TEMPLATE (tmpl);
18213 /* Returns true if we need to instantiate this template instance even if we
18214 know we aren't going to emit it.. */
18217 always_instantiate_p (tree decl)
18219 /* We always instantiate inline functions so that we can inline them. An
18220 explicit instantiation declaration prohibits implicit instantiation of
18221 non-inline functions. With high levels of optimization, we would
18222 normally inline non-inline functions -- but we're not allowed to do
18223 that for "extern template" functions. Therefore, we check
18224 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18225 return ((TREE_CODE (decl) == FUNCTION_DECL
18226 && DECL_DECLARED_INLINE_P (decl))
18227 /* And we need to instantiate static data members so that
18228 their initializers are available in integral constant
18230 || (TREE_CODE (decl) == VAR_DECL
18231 && decl_maybe_constant_var_p (decl)));
18234 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18235 instantiate it now, modifying TREE_TYPE (fn). */
18238 maybe_instantiate_noexcept (tree fn)
18240 tree fntype, spec, noex, clone;
18242 if (DECL_CLONED_FUNCTION_P (fn))
18243 fn = DECL_CLONED_FUNCTION (fn);
18244 fntype = TREE_TYPE (fn);
18245 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18247 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18250 noex = TREE_PURPOSE (spec);
18252 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18254 if (push_tinst_level (fn))
18256 push_access_scope (fn);
18257 input_location = DECL_SOURCE_LOCATION (fn);
18258 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18259 DEFERRED_NOEXCEPT_ARGS (noex),
18260 tf_warning_or_error, fn,
18261 /*function_p=*/false,
18262 /*integral_constant_expression_p=*/true);
18263 pop_access_scope (fn);
18264 pop_tinst_level ();
18265 spec = build_noexcept_spec (noex, tf_warning_or_error);
18266 if (spec == error_mark_node)
18267 spec = noexcept_false_spec;
18270 spec = noexcept_false_spec;
18274 /* This is an implicitly declared function, so NOEX is a list of
18275 other functions to evaluate and merge. */
18277 spec = noexcept_true_spec;
18278 for (elt = noex; elt; elt = OVL_NEXT (elt))
18280 tree fn = OVL_CURRENT (elt);
18282 maybe_instantiate_noexcept (fn);
18283 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18284 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18288 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18290 FOR_EACH_CLONE (clone, fn)
18292 if (TREE_TYPE (clone) == fntype)
18293 TREE_TYPE (clone) = TREE_TYPE (fn);
18295 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18299 /* Produce the definition of D, a _DECL generated from a template. If
18300 DEFER_OK is nonzero, then we don't have to actually do the
18301 instantiation now; we just have to do it sometime. Normally it is
18302 an error if this is an explicit instantiation but D is undefined.
18303 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18304 explicitly instantiated class template. */
18307 instantiate_decl (tree d, int defer_ok,
18308 bool expl_inst_class_mem_p)
18310 tree tmpl = DECL_TI_TEMPLATE (d);
18317 bool pattern_defined;
18319 location_t saved_loc = input_location;
18322 /* This function should only be used to instantiate templates for
18323 functions and static member variables. */
18324 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18325 || TREE_CODE (d) == VAR_DECL);
18327 /* Variables are never deferred; if instantiation is required, they
18328 are instantiated right away. That allows for better code in the
18329 case that an expression refers to the value of the variable --
18330 if the variable has a constant value the referring expression can
18331 take advantage of that fact. */
18332 if (TREE_CODE (d) == VAR_DECL
18333 || DECL_DECLARED_CONSTEXPR_P (d))
18336 /* Don't instantiate cloned functions. Instead, instantiate the
18337 functions they cloned. */
18338 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18339 d = DECL_CLONED_FUNCTION (d);
18341 if (DECL_TEMPLATE_INSTANTIATED (d)
18342 || (TREE_CODE (d) == FUNCTION_DECL
18343 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18344 || DECL_TEMPLATE_SPECIALIZATION (d))
18345 /* D has already been instantiated or explicitly specialized, so
18346 there's nothing for us to do here.
18348 It might seem reasonable to check whether or not D is an explicit
18349 instantiation, and, if so, stop here. But when an explicit
18350 instantiation is deferred until the end of the compilation,
18351 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18352 the instantiation. */
18355 /* Check to see whether we know that this template will be
18356 instantiated in some other file, as with "extern template"
18358 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18360 /* In general, we do not instantiate such templates. */
18361 if (external_p && !always_instantiate_p (d))
18364 gen_tmpl = most_general_template (tmpl);
18365 gen_args = DECL_TI_ARGS (d);
18367 if (tmpl != gen_tmpl)
18368 /* We should already have the extra args. */
18369 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18370 == TMPL_ARGS_DEPTH (gen_args));
18371 /* And what's in the hash table should match D. */
18372 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18373 || spec == NULL_TREE);
18375 /* This needs to happen before any tsubsting. */
18376 if (! push_tinst_level (d))
18379 timevar_push (TV_TEMPLATE_INST);
18381 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18382 for the instantiation. */
18383 td = template_for_substitution (d);
18384 code_pattern = DECL_TEMPLATE_RESULT (td);
18386 /* We should never be trying to instantiate a member of a class
18387 template or partial specialization. */
18388 gcc_assert (d != code_pattern);
18390 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18391 || DECL_TEMPLATE_SPECIALIZATION (td))
18392 /* In the case of a friend template whose definition is provided
18393 outside the class, we may have too many arguments. Drop the
18394 ones we don't need. The same is true for specializations. */
18395 args = get_innermost_template_args
18396 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18400 if (TREE_CODE (d) == FUNCTION_DECL)
18401 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18402 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18404 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18406 /* We may be in the middle of deferred access check. Disable it now. */
18407 push_deferring_access_checks (dk_no_deferred);
18409 /* Unless an explicit instantiation directive has already determined
18410 the linkage of D, remember that a definition is available for
18412 if (pattern_defined
18413 && !DECL_INTERFACE_KNOWN (d)
18414 && !DECL_NOT_REALLY_EXTERN (d))
18415 mark_definable (d);
18417 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18418 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18419 input_location = DECL_SOURCE_LOCATION (d);
18421 /* If D is a member of an explicitly instantiated class template,
18422 and no definition is available, treat it like an implicit
18424 if (!pattern_defined && expl_inst_class_mem_p
18425 && DECL_EXPLICIT_INSTANTIATION (d))
18427 /* Leave linkage flags alone on instantiations with anonymous
18429 if (TREE_PUBLIC (d))
18431 DECL_NOT_REALLY_EXTERN (d) = 0;
18432 DECL_INTERFACE_KNOWN (d) = 0;
18434 SET_DECL_IMPLICIT_INSTANTIATION (d);
18437 if (TREE_CODE (d) == FUNCTION_DECL)
18438 maybe_instantiate_noexcept (d);
18440 /* Recheck the substitutions to obtain any warning messages
18441 about ignoring cv qualifiers. Don't do this for artificial decls,
18442 as it breaks the context-sensitive substitution for lambda op(). */
18443 if (!defer_ok && !DECL_ARTIFICIAL (d))
18445 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18446 tree type = TREE_TYPE (gen);
18448 /* Make sure that we can see identifiers, and compute access
18449 correctly. D is already the target FUNCTION_DECL with the
18451 push_access_scope (d);
18453 if (TREE_CODE (gen) == FUNCTION_DECL)
18455 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18456 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18457 d, /*defer_ok*/true);
18458 /* Don't simply tsubst the function type, as that will give
18459 duplicate warnings about poor parameter qualifications.
18460 The function arguments are the same as the decl_arguments
18461 without the top level cv qualifiers. */
18462 type = TREE_TYPE (type);
18464 tsubst (type, gen_args, tf_warning_or_error, d);
18466 pop_access_scope (d);
18469 /* Defer all other templates, unless we have been explicitly
18470 forbidden from doing so. */
18471 if (/* If there is no definition, we cannot instantiate the
18474 /* If it's OK to postpone instantiation, do so. */
18476 /* If this is a static data member that will be defined
18477 elsewhere, we don't want to instantiate the entire data
18478 member, but we do want to instantiate the initializer so that
18479 we can substitute that elsewhere. */
18480 || (external_p && TREE_CODE (d) == VAR_DECL))
18482 /* The definition of the static data member is now required so
18483 we must substitute the initializer. */
18484 if (TREE_CODE (d) == VAR_DECL
18485 && !DECL_INITIAL (d)
18486 && DECL_INITIAL (code_pattern))
18490 bool const_init = false;
18492 ns = decl_namespace_context (d);
18493 push_nested_namespace (ns);
18494 push_nested_class (DECL_CONTEXT (d));
18495 init = tsubst_expr (DECL_INITIAL (code_pattern),
18497 tf_warning_or_error, NULL_TREE,
18498 /*integral_constant_expression_p=*/false);
18499 /* Make sure the initializer is still constant, in case of
18500 circular dependency (template/instantiate6.C). */
18502 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18503 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18504 /*asmspec_tree=*/NULL_TREE,
18505 LOOKUP_ONLYCONVERTING);
18506 pop_nested_class ();
18507 pop_nested_namespace (ns);
18510 /* We restore the source position here because it's used by
18511 add_pending_template. */
18512 input_location = saved_loc;
18514 if (at_eof && !pattern_defined
18515 && DECL_EXPLICIT_INSTANTIATION (d)
18516 && DECL_NOT_REALLY_EXTERN (d))
18519 The definition of a non-exported function template, a
18520 non-exported member function template, or a non-exported
18521 member function or static data member of a class template
18522 shall be present in every translation unit in which it is
18523 explicitly instantiated. */
18524 permerror (input_location, "explicit instantiation of %qD "
18525 "but no definition available", d);
18527 /* If we're in unevaluated context, we just wanted to get the
18528 constant value; this isn't an odr use, so don't queue
18529 a full instantiation. */
18530 if (cp_unevaluated_operand != 0)
18532 /* ??? Historically, we have instantiated inline functions, even
18533 when marked as "extern template". */
18534 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18535 add_pending_template (d);
18538 /* Tell the repository that D is available in this translation unit
18539 -- and see if it is supposed to be instantiated here. */
18540 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18542 /* In a PCH file, despite the fact that the repository hasn't
18543 requested instantiation in the PCH it is still possible that
18544 an instantiation will be required in a file that includes the
18547 add_pending_template (d);
18548 /* Instantiate inline functions so that the inliner can do its
18549 job, even though we'll not be emitting a copy of this
18551 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18555 need_push = !cfun || !global_bindings_p ();
18557 push_to_top_level ();
18559 /* Mark D as instantiated so that recursive calls to
18560 instantiate_decl do not try to instantiate it again. */
18561 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18563 /* Regenerate the declaration in case the template has been modified
18564 by a subsequent redeclaration. */
18565 regenerate_decl_from_template (d, td);
18567 /* We already set the file and line above. Reset them now in case
18568 they changed as a result of calling regenerate_decl_from_template. */
18569 input_location = DECL_SOURCE_LOCATION (d);
18571 if (TREE_CODE (d) == VAR_DECL)
18574 bool const_init = false;
18576 /* Clear out DECL_RTL; whatever was there before may not be right
18577 since we've reset the type of the declaration. */
18578 SET_DECL_RTL (d, NULL);
18579 DECL_IN_AGGR_P (d) = 0;
18581 /* The initializer is placed in DECL_INITIAL by
18582 regenerate_decl_from_template so we don't need to
18583 push/pop_access_scope again here. Pull it out so that
18584 cp_finish_decl can process it. */
18585 init = DECL_INITIAL (d);
18586 DECL_INITIAL (d) = NULL_TREE;
18587 DECL_INITIALIZED_P (d) = 0;
18589 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18590 initializer. That function will defer actual emission until
18591 we have a chance to determine linkage. */
18592 DECL_EXTERNAL (d) = 0;
18594 /* Enter the scope of D so that access-checking works correctly. */
18595 push_nested_class (DECL_CONTEXT (d));
18596 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18597 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18598 pop_nested_class ();
18600 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18601 synthesize_method (d);
18602 else if (TREE_CODE (d) == FUNCTION_DECL)
18604 htab_t saved_local_specializations;
18609 /* Save away the current list, in case we are instantiating one
18610 template from within the body of another. */
18611 saved_local_specializations = local_specializations;
18613 /* Set up the list of local specializations. */
18614 local_specializations = htab_create (37,
18615 hash_local_specialization,
18616 eq_local_specializations,
18619 /* Set up context. */
18620 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18622 /* Create substitution entries for the parameters. */
18623 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18624 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18625 spec_parm = DECL_ARGUMENTS (d);
18626 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18628 register_local_specialization (spec_parm, tmpl_parm);
18629 spec_parm = skip_artificial_parms_for (d, spec_parm);
18630 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18632 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18634 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18636 register_local_specialization (spec_parm, tmpl_parm);
18637 spec_parm = DECL_CHAIN (spec_parm);
18641 /* Register the (value) argument pack as a specialization of
18642 TMPL_PARM, then move on. */
18643 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18644 register_local_specialization (argpack, tmpl_parm);
18647 gcc_assert (!spec_parm);
18649 /* Substitute into the body of the function. */
18650 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18651 tf_warning_or_error, tmpl,
18652 /*integral_constant_expression_p=*/false);
18654 /* Set the current input_location to the end of the function
18655 so that finish_function knows where we are. */
18656 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18658 /* We don't need the local specializations any more. */
18659 htab_delete (local_specializations);
18660 local_specializations = saved_local_specializations;
18662 /* Finish the function. */
18663 d = finish_function (0);
18664 expand_or_defer_fn (d);
18667 /* We're not deferring instantiation any more. */
18668 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18671 pop_from_top_level ();
18674 input_location = saved_loc;
18675 pop_deferring_access_checks ();
18676 pop_tinst_level ();
18678 timevar_pop (TV_TEMPLATE_INST);
18683 /* Run through the list of templates that we wish we could
18684 instantiate, and instantiate any we can. RETRIES is the
18685 number of times we retry pending template instantiation. */
18688 instantiate_pending_templates (int retries)
18691 location_t saved_loc = input_location;
18693 /* Instantiating templates may trigger vtable generation. This in turn
18694 may require further template instantiations. We place a limit here
18695 to avoid infinite loop. */
18696 if (pending_templates && retries >= max_tinst_depth)
18698 tree decl = pending_templates->tinst->decl;
18700 error ("template instantiation depth exceeds maximum of %d"
18701 " instantiating %q+D, possibly from virtual table generation"
18702 " (use -ftemplate-depth= to increase the maximum)",
18703 max_tinst_depth, decl);
18704 if (TREE_CODE (decl) == FUNCTION_DECL)
18705 /* Pretend that we defined it. */
18706 DECL_INITIAL (decl) = error_mark_node;
18712 struct pending_template **t = &pending_templates;
18713 struct pending_template *last = NULL;
18717 tree instantiation = reopen_tinst_level ((*t)->tinst);
18718 bool complete = false;
18720 if (TYPE_P (instantiation))
18724 if (!COMPLETE_TYPE_P (instantiation))
18726 instantiate_class_template (instantiation);
18727 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18728 for (fn = TYPE_METHODS (instantiation);
18730 fn = TREE_CHAIN (fn))
18731 if (! DECL_ARTIFICIAL (fn))
18732 instantiate_decl (fn,
18734 /*expl_inst_class_mem_p=*/false);
18735 if (COMPLETE_TYPE_P (instantiation))
18739 complete = COMPLETE_TYPE_P (instantiation);
18743 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18744 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18747 = instantiate_decl (instantiation,
18749 /*expl_inst_class_mem_p=*/false);
18750 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18754 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18755 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18759 /* If INSTANTIATION has been instantiated, then we don't
18760 need to consider it again in the future. */
18768 current_tinst_level = NULL;
18770 last_pending_template = last;
18772 while (reconsider);
18774 input_location = saved_loc;
18777 /* Substitute ARGVEC into T, which is a list of initializers for
18778 either base class or a non-static data member. The TREE_PURPOSEs
18779 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18780 instantiate_decl. */
18783 tsubst_initializer_list (tree t, tree argvec)
18785 tree inits = NULL_TREE;
18787 for (; t; t = TREE_CHAIN (t))
18791 tree expanded_bases = NULL_TREE;
18792 tree expanded_arguments = NULL_TREE;
18795 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18800 /* Expand the base class expansion type into separate base
18802 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18803 tf_warning_or_error,
18805 if (expanded_bases == error_mark_node)
18808 /* We'll be building separate TREE_LISTs of arguments for
18810 len = TREE_VEC_LENGTH (expanded_bases);
18811 expanded_arguments = make_tree_vec (len);
18812 for (i = 0; i < len; i++)
18813 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18815 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18816 expand each argument in the TREE_VALUE of t. */
18817 expr = make_node (EXPR_PACK_EXPANSION);
18818 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18819 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18821 if (TREE_VALUE (t) == void_type_node)
18822 /* VOID_TYPE_NODE is used to indicate
18823 value-initialization. */
18825 for (i = 0; i < len; i++)
18826 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18830 /* Substitute parameter packs into each argument in the
18832 in_base_initializer = 1;
18833 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18835 tree expanded_exprs;
18837 /* Expand the argument. */
18838 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18840 = tsubst_pack_expansion (expr, argvec,
18841 tf_warning_or_error,
18843 if (expanded_exprs == error_mark_node)
18846 /* Prepend each of the expanded expressions to the
18847 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18848 for (i = 0; i < len; i++)
18850 TREE_VEC_ELT (expanded_arguments, i) =
18851 tree_cons (NULL_TREE,
18852 TREE_VEC_ELT (expanded_exprs, i),
18853 TREE_VEC_ELT (expanded_arguments, i));
18856 in_base_initializer = 0;
18858 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18859 since we built them backwards. */
18860 for (i = 0; i < len; i++)
18862 TREE_VEC_ELT (expanded_arguments, i) =
18863 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18868 for (i = 0; i < len; ++i)
18870 if (expanded_bases)
18872 decl = TREE_VEC_ELT (expanded_bases, i);
18873 decl = expand_member_init (decl);
18874 init = TREE_VEC_ELT (expanded_arguments, i);
18878 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18879 tf_warning_or_error, NULL_TREE);
18881 decl = expand_member_init (decl);
18882 if (decl && !DECL_P (decl))
18883 in_base_initializer = 1;
18885 init = TREE_VALUE (t);
18886 if (init != void_type_node)
18887 init = tsubst_expr (init, argvec,
18888 tf_warning_or_error, NULL_TREE,
18889 /*integral_constant_expression_p=*/false);
18890 in_base_initializer = 0;
18895 init = build_tree_list (decl, init);
18896 TREE_CHAIN (init) = inits;
18904 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18907 set_current_access_from_decl (tree decl)
18909 if (TREE_PRIVATE (decl))
18910 current_access_specifier = access_private_node;
18911 else if (TREE_PROTECTED (decl))
18912 current_access_specifier = access_protected_node;
18914 current_access_specifier = access_public_node;
18917 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18918 is the instantiation (which should have been created with
18919 start_enum) and ARGS are the template arguments to use. */
18922 tsubst_enum (tree tag, tree newtag, tree args)
18926 if (SCOPED_ENUM_P (newtag))
18927 begin_scope (sk_scoped_enum, newtag);
18929 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18934 decl = TREE_VALUE (e);
18935 /* Note that in a template enum, the TREE_VALUE is the
18936 CONST_DECL, not the corresponding INTEGER_CST. */
18937 value = tsubst_expr (DECL_INITIAL (decl),
18938 args, tf_warning_or_error, NULL_TREE,
18939 /*integral_constant_expression_p=*/true);
18941 /* Give this enumeration constant the correct access. */
18942 set_current_access_from_decl (decl);
18944 /* Actually build the enumerator itself. */
18946 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
18949 if (SCOPED_ENUM_P (newtag))
18952 finish_enum_value_list (newtag);
18953 finish_enum (newtag);
18955 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
18956 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
18959 /* DECL is a FUNCTION_DECL that is a template specialization. Return
18960 its type -- but without substituting the innermost set of template
18961 arguments. So, innermost set of template parameters will appear in
18965 get_mostly_instantiated_function_type (tree decl)
18973 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
18974 targs = DECL_TI_ARGS (decl);
18975 tparms = DECL_TEMPLATE_PARMS (tmpl);
18976 parm_depth = TMPL_PARMS_DEPTH (tparms);
18978 /* There should be as many levels of arguments as there are levels
18980 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18982 fn_type = TREE_TYPE (tmpl);
18984 if (parm_depth == 1)
18985 /* No substitution is necessary. */
18992 /* Replace the innermost level of the TARGS with NULL_TREEs to
18993 let tsubst know not to substitute for those parameters. */
18994 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18995 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18996 SET_TMPL_ARGS_LEVEL (partial_args, i,
18997 TMPL_ARGS_LEVEL (targs, i));
18998 SET_TMPL_ARGS_LEVEL (partial_args,
18999 TMPL_ARGS_DEPTH (targs),
19000 make_tree_vec (DECL_NTPARMS (tmpl)));
19002 /* Make sure that we can see identifiers, and compute access
19004 push_access_scope (decl);
19006 ++processing_template_decl;
19007 /* Now, do the (partial) substitution to figure out the
19008 appropriate function type. */
19009 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19010 --processing_template_decl;
19012 /* Substitute into the template parameters to obtain the real
19013 innermost set of parameters. This step is important if the
19014 innermost set of template parameters contains value
19015 parameters whose types depend on outer template parameters. */
19016 TREE_VEC_LENGTH (partial_args)--;
19017 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19019 pop_access_scope (decl);
19025 /* Return truthvalue if we're processing a template different from
19026 the last one involved in diagnostics. */
19028 problematic_instantiation_changed (void)
19030 return current_tinst_level != last_error_tinst_level;
19033 /* Remember current template involved in diagnostics. */
19035 record_last_problematic_instantiation (void)
19037 last_error_tinst_level = current_tinst_level;
19040 struct tinst_level *
19041 current_instantiation (void)
19043 return current_tinst_level;
19046 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19047 type. Return zero for ok, nonzero for disallowed. Issue error and
19048 warning messages under control of COMPLAIN. */
19051 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19053 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19055 else if (POINTER_TYPE_P (type))
19057 else if (TYPE_PTR_TO_MEMBER_P (type))
19059 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19061 else if (TREE_CODE (type) == TYPENAME_TYPE)
19063 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19065 else if (TREE_CODE (type) == NULLPTR_TYPE)
19068 if (complain & tf_error)
19070 if (type == error_mark_node)
19071 inform (input_location, "invalid template non-type parameter");
19073 error ("%q#T is not a valid type for a template non-type parameter",
19079 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19080 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19083 dependent_type_p_r (tree type)
19089 A type is dependent if it is:
19091 -- a template parameter. Template template parameters are types
19092 for us (since TYPE_P holds true for them) so we handle
19094 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19095 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19097 /* -- a qualified-id with a nested-name-specifier which contains a
19098 class-name that names a dependent type or whose unqualified-id
19099 names a dependent type. */
19100 if (TREE_CODE (type) == TYPENAME_TYPE)
19102 /* -- a cv-qualified type where the cv-unqualified type is
19104 type = TYPE_MAIN_VARIANT (type);
19105 /* -- a compound type constructed from any dependent type. */
19106 if (TYPE_PTR_TO_MEMBER_P (type))
19107 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19108 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19110 else if (TREE_CODE (type) == POINTER_TYPE
19111 || TREE_CODE (type) == REFERENCE_TYPE)
19112 return dependent_type_p (TREE_TYPE (type));
19113 else if (TREE_CODE (type) == FUNCTION_TYPE
19114 || TREE_CODE (type) == METHOD_TYPE)
19118 if (dependent_type_p (TREE_TYPE (type)))
19120 for (arg_type = TYPE_ARG_TYPES (type);
19122 arg_type = TREE_CHAIN (arg_type))
19123 if (dependent_type_p (TREE_VALUE (arg_type)))
19127 /* -- an array type constructed from any dependent type or whose
19128 size is specified by a constant expression that is
19131 We checked for type- and value-dependence of the bounds in
19132 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19133 if (TREE_CODE (type) == ARRAY_TYPE)
19135 if (TYPE_DOMAIN (type)
19136 && dependent_type_p (TYPE_DOMAIN (type)))
19138 return dependent_type_p (TREE_TYPE (type));
19141 /* -- a template-id in which either the template name is a template
19143 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19145 /* ... or any of the template arguments is a dependent type or
19146 an expression that is type-dependent or value-dependent. */
19147 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19148 && (any_dependent_template_arguments_p
19149 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19152 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19153 dependent; if the argument of the `typeof' expression is not
19154 type-dependent, then it should already been have resolved. */
19155 if (TREE_CODE (type) == TYPEOF_TYPE
19156 || TREE_CODE (type) == DECLTYPE_TYPE
19157 || TREE_CODE (type) == UNDERLYING_TYPE)
19160 /* A template argument pack is dependent if any of its packed
19162 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19164 tree args = ARGUMENT_PACK_ARGS (type);
19165 int i, len = TREE_VEC_LENGTH (args);
19166 for (i = 0; i < len; ++i)
19167 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19171 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19172 be template parameters. */
19173 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19176 /* The standard does not specifically mention types that are local
19177 to template functions or local classes, but they should be
19178 considered dependent too. For example:
19180 template <int I> void f() {
19185 The size of `E' cannot be known until the value of `I' has been
19186 determined. Therefore, `E' must be considered dependent. */
19187 scope = TYPE_CONTEXT (type);
19188 if (scope && TYPE_P (scope))
19189 return dependent_type_p (scope);
19190 /* Don't use type_dependent_expression_p here, as it can lead
19191 to infinite recursion trying to determine whether a lambda
19192 nested in a lambda is dependent (c++/47687). */
19193 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19194 && DECL_LANG_SPECIFIC (scope)
19195 && DECL_TEMPLATE_INFO (scope)
19196 && (any_dependent_template_arguments_p
19197 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19200 /* Other types are non-dependent. */
19204 /* Returns TRUE if TYPE is dependent, in the sense of
19205 [temp.dep.type]. Note that a NULL type is considered dependent. */
19208 dependent_type_p (tree type)
19210 /* If there are no template parameters in scope, then there can't be
19211 any dependent types. */
19212 if (!processing_template_decl)
19214 /* If we are not processing a template, then nobody should be
19215 providing us with a dependent type. */
19217 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19221 /* If the type is NULL, we have not computed a type for the entity
19222 in question; in that case, the type is dependent. */
19226 /* Erroneous types can be considered non-dependent. */
19227 if (type == error_mark_node)
19230 /* If we have not already computed the appropriate value for TYPE,
19232 if (!TYPE_DEPENDENT_P_VALID (type))
19234 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19235 TYPE_DEPENDENT_P_VALID (type) = 1;
19238 return TYPE_DEPENDENT_P (type);
19241 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19242 lookup. In other words, a dependent type that is not the current
19246 dependent_scope_p (tree scope)
19248 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19249 && !currently_open_class (scope));
19252 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19253 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19256 /* Note that this predicate is not appropriate for general expressions;
19257 only constant expressions (that satisfy potential_constant_expression)
19258 can be tested for value dependence.
19260 We should really also have a predicate for "instantiation-dependent".
19262 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19263 (what about instantiation-dependent constant-expressions?)
19264 is_late_template_attribute: defer if instantiation-dependent.
19265 compute_array_index_type: proceed if constant and not t- or v-dependent
19266 if instantiation-dependent, need to remember full expression
19267 uses_template_parms: FIXME - need to audit callers
19268 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19269 dependent_type_p [array_type]: dependent if index type is dependent
19271 static_assert - instantiation-dependent */
19274 value_dependent_expression_p (tree expression)
19276 if (!processing_template_decl)
19279 /* A name declared with a dependent type. */
19280 if (DECL_P (expression) && type_dependent_expression_p (expression))
19283 switch (TREE_CODE (expression))
19285 case IDENTIFIER_NODE:
19286 /* A name that has not been looked up -- must be dependent. */
19289 case TEMPLATE_PARM_INDEX:
19290 /* A non-type template parm. */
19294 /* A non-type template parm. */
19295 if (DECL_TEMPLATE_PARM_P (expression))
19297 return value_dependent_expression_p (DECL_INITIAL (expression));
19300 /* A constant with literal type and is initialized
19301 with an expression that is value-dependent. */
19302 if (DECL_INITIAL (expression)
19303 && decl_constant_var_p (expression)
19304 && value_dependent_expression_p (DECL_INITIAL (expression)))
19308 case DYNAMIC_CAST_EXPR:
19309 case STATIC_CAST_EXPR:
19310 case CONST_CAST_EXPR:
19311 case REINTERPRET_CAST_EXPR:
19313 /* These expressions are value-dependent if the type to which
19314 the cast occurs is dependent or the expression being casted
19315 is value-dependent. */
19317 tree type = TREE_TYPE (expression);
19319 if (dependent_type_p (type))
19322 /* A functional cast has a list of operands. */
19323 expression = TREE_OPERAND (expression, 0);
19326 /* If there are no operands, it must be an expression such
19327 as "int()". This should not happen for aggregate types
19328 because it would form non-constant expressions. */
19329 gcc_assert (cxx_dialect >= cxx0x
19330 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19335 if (TREE_CODE (expression) == TREE_LIST)
19336 return any_value_dependent_elements_p (expression);
19338 return value_dependent_expression_p (expression);
19344 /* A `sizeof' expression is value-dependent if the operand is
19345 type-dependent or is a pack expansion. */
19346 expression = TREE_OPERAND (expression, 0);
19347 if (PACK_EXPANSION_P (expression))
19349 else if (TYPE_P (expression))
19350 return dependent_type_p (expression);
19351 return type_dependent_expression_p (expression);
19353 case AT_ENCODE_EXPR:
19354 /* An 'encode' expression is value-dependent if the operand is
19356 expression = TREE_OPERAND (expression, 0);
19357 return dependent_type_p (expression);
19359 case NOEXCEPT_EXPR:
19360 expression = TREE_OPERAND (expression, 0);
19361 return type_dependent_expression_p (expression);
19365 tree name = TREE_OPERAND (expression, 1);
19366 return value_dependent_expression_p (name);
19369 case COMPONENT_REF:
19370 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19371 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19373 case NONTYPE_ARGUMENT_PACK:
19374 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19375 is value-dependent. */
19377 tree values = ARGUMENT_PACK_ARGS (expression);
19378 int i, len = TREE_VEC_LENGTH (values);
19380 for (i = 0; i < len; ++i)
19381 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19389 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19390 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19391 || (type2 ? dependent_type_p (type2) : false));
19395 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19396 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19399 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19400 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19404 tree op = TREE_OPERAND (expression, 0);
19405 return (value_dependent_expression_p (op)
19406 || has_value_dependent_address (op));
19411 tree fn = get_callee_fndecl (expression);
19413 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19415 nargs = call_expr_nargs (expression);
19416 for (i = 0; i < nargs; ++i)
19418 tree op = CALL_EXPR_ARG (expression, i);
19419 /* In a call to a constexpr member function, look through the
19420 implicit ADDR_EXPR on the object argument so that it doesn't
19421 cause the call to be considered value-dependent. We also
19422 look through it in potential_constant_expression. */
19423 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19424 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19425 && TREE_CODE (op) == ADDR_EXPR)
19426 op = TREE_OPERAND (op, 0);
19427 if (value_dependent_expression_p (op))
19433 case TEMPLATE_ID_EXPR:
19434 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19436 return type_dependent_expression_p (expression);
19442 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19443 if (value_dependent_expression_p (val))
19449 /* A constant expression is value-dependent if any subexpression is
19450 value-dependent. */
19451 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19453 case tcc_reference:
19455 case tcc_comparison:
19457 case tcc_expression:
19460 int i, len = cp_tree_operand_length (expression);
19462 for (i = 0; i < len; i++)
19464 tree t = TREE_OPERAND (expression, i);
19466 /* In some cases, some of the operands may be missing.l
19467 (For example, in the case of PREDECREMENT_EXPR, the
19468 amount to increment by may be missing.) That doesn't
19469 make the expression dependent. */
19470 if (t && value_dependent_expression_p (t))
19481 /* The expression is not value-dependent. */
19485 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19486 [temp.dep.expr]. Note that an expression with no type is
19487 considered dependent. Other parts of the compiler arrange for an
19488 expression with type-dependent subexpressions to have no type, so
19489 this function doesn't have to be fully recursive. */
19492 type_dependent_expression_p (tree expression)
19494 if (!processing_template_decl)
19497 if (expression == error_mark_node)
19500 /* An unresolved name is always dependent. */
19501 if (TREE_CODE (expression) == IDENTIFIER_NODE
19502 || TREE_CODE (expression) == USING_DECL)
19505 /* Some expression forms are never type-dependent. */
19506 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19507 || TREE_CODE (expression) == SIZEOF_EXPR
19508 || TREE_CODE (expression) == ALIGNOF_EXPR
19509 || TREE_CODE (expression) == AT_ENCODE_EXPR
19510 || TREE_CODE (expression) == NOEXCEPT_EXPR
19511 || TREE_CODE (expression) == TRAIT_EXPR
19512 || TREE_CODE (expression) == TYPEID_EXPR
19513 || TREE_CODE (expression) == DELETE_EXPR
19514 || TREE_CODE (expression) == VEC_DELETE_EXPR
19515 || TREE_CODE (expression) == THROW_EXPR)
19518 /* The types of these expressions depends only on the type to which
19519 the cast occurs. */
19520 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19521 || TREE_CODE (expression) == STATIC_CAST_EXPR
19522 || TREE_CODE (expression) == CONST_CAST_EXPR
19523 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19524 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19525 || TREE_CODE (expression) == CAST_EXPR)
19526 return dependent_type_p (TREE_TYPE (expression));
19528 /* The types of these expressions depends only on the type created
19529 by the expression. */
19530 if (TREE_CODE (expression) == NEW_EXPR
19531 || TREE_CODE (expression) == VEC_NEW_EXPR)
19533 /* For NEW_EXPR tree nodes created inside a template, either
19534 the object type itself or a TREE_LIST may appear as the
19536 tree type = TREE_OPERAND (expression, 1);
19537 if (TREE_CODE (type) == TREE_LIST)
19538 /* This is an array type. We need to check array dimensions
19540 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19541 || value_dependent_expression_p
19542 (TREE_OPERAND (TREE_VALUE (type), 1));
19544 return dependent_type_p (type);
19547 if (TREE_CODE (expression) == SCOPE_REF)
19549 tree scope = TREE_OPERAND (expression, 0);
19550 tree name = TREE_OPERAND (expression, 1);
19552 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19553 contains an identifier associated by name lookup with one or more
19554 declarations declared with a dependent type, or...a
19555 nested-name-specifier or qualified-id that names a member of an
19556 unknown specialization. */
19557 return (type_dependent_expression_p (name)
19558 || dependent_scope_p (scope));
19561 if (TREE_CODE (expression) == FUNCTION_DECL
19562 && DECL_LANG_SPECIFIC (expression)
19563 && DECL_TEMPLATE_INFO (expression)
19564 && (any_dependent_template_arguments_p
19565 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19568 if (TREE_CODE (expression) == TEMPLATE_DECL
19569 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19572 if (TREE_CODE (expression) == STMT_EXPR)
19573 expression = stmt_expr_value_expr (expression);
19575 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19580 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19582 if (type_dependent_expression_p (elt))
19588 /* A static data member of the current instantiation with incomplete
19589 array type is type-dependent, as the definition and specializations
19590 can have different bounds. */
19591 if (TREE_CODE (expression) == VAR_DECL
19592 && DECL_CLASS_SCOPE_P (expression)
19593 && dependent_type_p (DECL_CONTEXT (expression))
19594 && VAR_HAD_UNKNOWN_BOUND (expression))
19597 if (TREE_TYPE (expression) == unknown_type_node)
19599 if (TREE_CODE (expression) == ADDR_EXPR)
19600 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19601 if (TREE_CODE (expression) == COMPONENT_REF
19602 || TREE_CODE (expression) == OFFSET_REF)
19604 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19606 expression = TREE_OPERAND (expression, 1);
19607 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19610 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19611 if (TREE_CODE (expression) == SCOPE_REF)
19614 if (BASELINK_P (expression))
19615 expression = BASELINK_FUNCTIONS (expression);
19617 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19619 if (any_dependent_template_arguments_p
19620 (TREE_OPERAND (expression, 1)))
19622 expression = TREE_OPERAND (expression, 0);
19624 gcc_assert (TREE_CODE (expression) == OVERLOAD
19625 || TREE_CODE (expression) == FUNCTION_DECL);
19629 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19631 expression = OVL_NEXT (expression);
19636 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19638 return (dependent_type_p (TREE_TYPE (expression)));
19641 /* Like type_dependent_expression_p, but it also works while not processing
19642 a template definition, i.e. during substitution or mangling. */
19645 type_dependent_expression_p_push (tree expr)
19648 ++processing_template_decl;
19649 b = type_dependent_expression_p (expr);
19650 --processing_template_decl;
19654 /* Returns TRUE if ARGS contains a type-dependent expression. */
19657 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19662 FOR_EACH_VEC_ELT (tree, args, i, arg)
19664 if (type_dependent_expression_p (arg))
19670 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19671 expressions) contains any type-dependent expressions. */
19674 any_type_dependent_elements_p (const_tree list)
19676 for (; list; list = TREE_CHAIN (list))
19677 if (value_dependent_expression_p (TREE_VALUE (list)))
19683 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19684 expressions) contains any value-dependent expressions. */
19687 any_value_dependent_elements_p (const_tree list)
19689 for (; list; list = TREE_CHAIN (list))
19690 if (value_dependent_expression_p (TREE_VALUE (list)))
19696 /* Returns TRUE if the ARG (a template argument) is dependent. */
19699 dependent_template_arg_p (tree arg)
19701 if (!processing_template_decl)
19704 /* Assume a template argument that was wrongly written by the user
19705 is dependent. This is consistent with what
19706 any_dependent_template_arguments_p [that calls this function]
19708 if (!arg || arg == error_mark_node)
19711 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19712 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19714 if (TREE_CODE (arg) == TEMPLATE_DECL
19715 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19716 return dependent_template_p (arg);
19717 else if (ARGUMENT_PACK_P (arg))
19719 tree args = ARGUMENT_PACK_ARGS (arg);
19720 int i, len = TREE_VEC_LENGTH (args);
19721 for (i = 0; i < len; ++i)
19723 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19729 else if (TYPE_P (arg))
19730 return dependent_type_p (arg);
19732 return (type_dependent_expression_p (arg)
19733 || value_dependent_expression_p (arg));
19736 /* Returns true if ARGS (a collection of template arguments) contains
19737 any types that require structural equality testing. */
19740 any_template_arguments_need_structural_equality_p (tree args)
19747 if (args == error_mark_node)
19750 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19752 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19753 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19755 tree arg = TREE_VEC_ELT (level, j);
19756 tree packed_args = NULL_TREE;
19759 if (ARGUMENT_PACK_P (arg))
19761 /* Look inside the argument pack. */
19762 packed_args = ARGUMENT_PACK_ARGS (arg);
19763 len = TREE_VEC_LENGTH (packed_args);
19766 for (k = 0; k < len; ++k)
19769 arg = TREE_VEC_ELT (packed_args, k);
19771 if (error_operand_p (arg))
19773 else if (TREE_CODE (arg) == TEMPLATE_DECL
19774 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19776 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19778 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19779 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19788 /* Returns true if ARGS (a collection of template arguments) contains
19789 any dependent arguments. */
19792 any_dependent_template_arguments_p (const_tree args)
19799 if (args == error_mark_node)
19802 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19804 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19805 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19806 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19813 /* Returns TRUE if the template TMPL is dependent. */
19816 dependent_template_p (tree tmpl)
19818 if (TREE_CODE (tmpl) == OVERLOAD)
19822 if (dependent_template_p (OVL_CURRENT (tmpl)))
19824 tmpl = OVL_NEXT (tmpl);
19829 /* Template template parameters are dependent. */
19830 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19831 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19833 /* So are names that have not been looked up. */
19834 if (TREE_CODE (tmpl) == SCOPE_REF
19835 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19837 /* So are member templates of dependent classes. */
19838 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19839 return dependent_type_p (DECL_CONTEXT (tmpl));
19843 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19846 dependent_template_id_p (tree tmpl, tree args)
19848 return (dependent_template_p (tmpl)
19849 || any_dependent_template_arguments_p (args));
19852 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19856 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19860 if (!processing_template_decl)
19863 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19865 tree decl = TREE_VEC_ELT (declv, i);
19866 tree init = TREE_VEC_ELT (initv, i);
19867 tree cond = TREE_VEC_ELT (condv, i);
19868 tree incr = TREE_VEC_ELT (incrv, i);
19870 if (type_dependent_expression_p (decl))
19873 if (init && type_dependent_expression_p (init))
19876 if (type_dependent_expression_p (cond))
19879 if (COMPARISON_CLASS_P (cond)
19880 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19881 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19884 if (TREE_CODE (incr) == MODOP_EXPR)
19886 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19887 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19890 else if (type_dependent_expression_p (incr))
19892 else if (TREE_CODE (incr) == MODIFY_EXPR)
19894 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19896 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19898 tree t = TREE_OPERAND (incr, 1);
19899 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19900 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19909 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19910 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19911 no such TYPE can be found. Note that this function peers inside
19912 uninstantiated templates and therefore should be used only in
19913 extremely limited situations. ONLY_CURRENT_P restricts this
19914 peering to the currently open classes hierarchy (which is required
19915 when comparing types). */
19918 resolve_typename_type (tree type, bool only_current_p)
19927 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19929 scope = TYPE_CONTEXT (type);
19930 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19931 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19932 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19933 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19934 identifier of the TYPENAME_TYPE anymore.
19935 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19936 TYPENAME_TYPE instead, we avoid messing up with a possible
19937 typedef variant case. */
19938 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
19940 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
19941 it first before we can figure out what NAME refers to. */
19942 if (TREE_CODE (scope) == TYPENAME_TYPE)
19943 scope = resolve_typename_type (scope, only_current_p);
19944 /* If we don't know what SCOPE refers to, then we cannot resolve the
19946 if (TREE_CODE (scope) == TYPENAME_TYPE)
19948 /* If the SCOPE is a template type parameter, we have no way of
19949 resolving the name. */
19950 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
19952 /* If the SCOPE is not the current instantiation, there's no reason
19953 to look inside it. */
19954 if (only_current_p && !currently_open_class (scope))
19956 /* If this is a typedef, we don't want to look inside (c++/11987). */
19957 if (typedef_variant_p (type))
19959 /* If SCOPE isn't the template itself, it will not have a valid
19960 TYPE_FIELDS list. */
19961 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
19962 /* scope is either the template itself or a compatible instantiation
19963 like X<T>, so look up the name in the original template. */
19964 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
19966 /* scope is a partial instantiation, so we can't do the lookup or we
19967 will lose the template arguments. */
19969 /* Enter the SCOPE so that name lookup will be resolved as if we
19970 were in the class definition. In particular, SCOPE will no
19971 longer be considered a dependent type. */
19972 pushed_scope = push_scope (scope);
19973 /* Look up the declaration. */
19974 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
19975 tf_warning_or_error);
19977 result = NULL_TREE;
19979 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
19980 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
19983 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
19984 && TREE_CODE (decl) == TYPE_DECL)
19986 result = TREE_TYPE (decl);
19987 if (result == error_mark_node)
19988 result = NULL_TREE;
19990 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19991 && DECL_CLASS_TEMPLATE_P (decl))
19995 /* Obtain the template and the arguments. */
19996 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19997 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19998 /* Instantiate the template. */
19999 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20000 /*entering_scope=*/0,
20001 tf_error | tf_user);
20002 if (result == error_mark_node)
20003 result = NULL_TREE;
20006 /* Leave the SCOPE. */
20008 pop_scope (pushed_scope);
20010 /* If we failed to resolve it, return the original typename. */
20014 /* If lookup found a typename type, resolve that too. */
20015 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20017 /* Ill-formed programs can cause infinite recursion here, so we
20018 must catch that. */
20019 TYPENAME_IS_RESOLVING_P (type) = 1;
20020 result = resolve_typename_type (result, only_current_p);
20021 TYPENAME_IS_RESOLVING_P (type) = 0;
20024 /* Qualify the resulting type. */
20025 quals = cp_type_quals (type);
20027 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20032 /* EXPR is an expression which is not type-dependent. Return a proxy
20033 for EXPR that can be used to compute the types of larger
20034 expressions containing EXPR. */
20037 build_non_dependent_expr (tree expr)
20041 #ifdef ENABLE_CHECKING
20042 /* Try to get a constant value for all non-type-dependent expressions in
20043 order to expose bugs in *_dependent_expression_p and constexpr. */
20044 if (cxx_dialect >= cxx0x)
20045 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20048 /* Preserve OVERLOADs; the functions must be available to resolve
20051 if (TREE_CODE (inner_expr) == STMT_EXPR)
20052 inner_expr = stmt_expr_value_expr (inner_expr);
20053 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20054 inner_expr = TREE_OPERAND (inner_expr, 0);
20055 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20056 inner_expr = TREE_OPERAND (inner_expr, 1);
20057 if (is_overloaded_fn (inner_expr)
20058 || TREE_CODE (inner_expr) == OFFSET_REF)
20060 /* There is no need to return a proxy for a variable. */
20061 if (TREE_CODE (expr) == VAR_DECL)
20063 /* Preserve string constants; conversions from string constants to
20064 "char *" are allowed, even though normally a "const char *"
20065 cannot be used to initialize a "char *". */
20066 if (TREE_CODE (expr) == STRING_CST)
20068 /* Preserve arithmetic constants, as an optimization -- there is no
20069 reason to create a new node. */
20070 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20072 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20073 There is at least one place where we want to know that a
20074 particular expression is a throw-expression: when checking a ?:
20075 expression, there are special rules if the second or third
20076 argument is a throw-expression. */
20077 if (TREE_CODE (expr) == THROW_EXPR)
20080 /* Don't wrap an initializer list, we need to be able to look inside. */
20081 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20084 if (TREE_CODE (expr) == COND_EXPR)
20085 return build3 (COND_EXPR,
20087 TREE_OPERAND (expr, 0),
20088 (TREE_OPERAND (expr, 1)
20089 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20090 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20091 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20092 if (TREE_CODE (expr) == COMPOUND_EXPR
20093 && !COMPOUND_EXPR_OVERLOADED (expr))
20094 return build2 (COMPOUND_EXPR,
20096 TREE_OPERAND (expr, 0),
20097 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20099 /* If the type is unknown, it can't really be non-dependent */
20100 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20102 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20103 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20106 /* ARGS is a vector of expressions as arguments to a function call.
20107 Replace the arguments with equivalent non-dependent expressions.
20108 This modifies ARGS in place. */
20111 make_args_non_dependent (VEC(tree,gc) *args)
20116 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20118 tree newarg = build_non_dependent_expr (arg);
20120 VEC_replace (tree, args, ix, newarg);
20124 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20125 with a level one deeper than the actual template parms. */
20130 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20131 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20132 TYPE_DECL, get_identifier ("auto"), au);
20133 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20134 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20135 (0, processing_template_decl + 1, processing_template_decl + 1,
20136 0, TYPE_NAME (au), NULL_TREE);
20137 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20138 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20139 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20144 /* Given type ARG, return std::initializer_list<ARG>. */
20149 tree std_init_list = namespace_binding
20150 (get_identifier ("initializer_list"), std_node);
20152 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20154 error ("deducing from brace-enclosed initializer list requires "
20155 "#include <initializer_list>");
20156 return error_mark_node;
20158 argvec = make_tree_vec (1);
20159 TREE_VEC_ELT (argvec, 0) = arg;
20160 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20161 NULL_TREE, 0, tf_warning_or_error);
20164 /* Replace auto in TYPE with std::initializer_list<auto>. */
20167 listify_autos (tree type, tree auto_node)
20169 tree init_auto = listify (auto_node);
20170 tree argvec = make_tree_vec (1);
20171 TREE_VEC_ELT (argvec, 0) = init_auto;
20172 if (processing_template_decl)
20173 argvec = add_to_template_args (current_template_args (), argvec);
20174 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20177 /* walk_tree helper for do_auto_deduction. */
20180 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20183 /* Is this a variable with the type we're looking for? */
20185 && TREE_TYPE (*tp) == type)
20191 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20192 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20195 do_auto_deduction (tree type, tree init, tree auto_node)
20197 tree parms, tparms, targs;
20202 if (processing_template_decl
20203 && (TREE_TYPE (init) == NULL_TREE
20204 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20205 /* Not enough information to try this yet. */
20208 /* The name of the object being declared shall not appear in the
20209 initializer expression. */
20210 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20213 error ("variable %q#D with %<auto%> type used in its own "
20214 "initializer", decl);
20215 return error_mark_node;
20218 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20219 with either a new invented type template parameter U or, if the
20220 initializer is a braced-init-list (8.5.4), with
20221 std::initializer_list<U>. */
20222 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20223 type = listify_autos (type, auto_node);
20225 init = resolve_nondeduced_context (init);
20227 parms = build_tree_list (NULL_TREE, type);
20229 tparms = make_tree_vec (1);
20230 targs = make_tree_vec (1);
20231 TREE_VEC_ELT (tparms, 0)
20232 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20233 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20234 DEDUCE_CALL, LOOKUP_NORMAL,
20235 /*explain_p=*/false);
20238 if (processing_template_decl)
20239 /* Try again at instantiation time. */
20241 if (type && type != error_mark_node)
20242 /* If type is error_mark_node a diagnostic must have been
20243 emitted by now. Also, having a mention to '<type error>'
20244 in the diagnostic is not really useful to the user. */
20245 error ("unable to deduce %qT from %qE", type, init);
20246 return error_mark_node;
20249 /* If the list of declarators contains more than one declarator, the type
20250 of each declared variable is determined as described above. If the
20251 type deduced for the template parameter U is not the same in each
20252 deduction, the program is ill-formed. */
20253 if (TREE_TYPE (auto_node)
20254 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20256 error ("inconsistent deduction for %qT: %qT and then %qT",
20257 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20258 return error_mark_node;
20260 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20262 if (processing_template_decl)
20263 targs = add_to_template_args (current_template_args (), targs);
20264 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20267 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20271 splice_late_return_type (tree type, tree late_return_type)
20275 if (late_return_type == NULL_TREE)
20277 argvec = make_tree_vec (1);
20278 TREE_VEC_ELT (argvec, 0) = late_return_type;
20279 if (processing_template_parmlist)
20280 /* For a late-specified return type in a template type-parameter, we
20281 need to add a dummy argument level for its parmlist. */
20282 argvec = add_to_template_args
20283 (make_tree_vec (processing_template_parmlist), argvec);
20284 if (current_template_parms)
20285 argvec = add_to_template_args (current_template_args (), argvec);
20286 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20289 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20292 is_auto (const_tree type)
20294 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20295 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20301 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20302 appear as a type-specifier for the declaration in question, we don't
20303 have to look through the whole type. */
20306 type_uses_auto (tree type)
20308 enum tree_code code;
20309 if (is_auto (type))
20312 code = TREE_CODE (type);
20314 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20315 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20316 || code == METHOD_TYPE || code == ARRAY_TYPE)
20317 return type_uses_auto (TREE_TYPE (type));
20319 if (TYPE_PTRMEMFUNC_P (type))
20320 return type_uses_auto (TREE_TYPE (TREE_TYPE
20321 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20326 /* For a given template T, return the vector of typedefs referenced
20327 in T for which access check is needed at T instantiation time.
20328 T is either a FUNCTION_DECL or a RECORD_TYPE.
20329 Those typedefs were added to T by the function
20330 append_type_to_template_for_access_check. */
20332 VEC(qualified_typedef_usage_t,gc)*
20333 get_types_needing_access_check (tree t)
20336 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20338 if (!t || t == error_mark_node)
20341 if (!(ti = get_template_info (t)))
20344 if (CLASS_TYPE_P (t)
20345 || TREE_CODE (t) == FUNCTION_DECL)
20347 if (!TI_TEMPLATE (ti))
20350 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20356 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20357 tied to T. That list of typedefs will be access checked at
20358 T instantiation time.
20359 T is either a FUNCTION_DECL or a RECORD_TYPE.
20360 TYPE_DECL is a TYPE_DECL node representing a typedef.
20361 SCOPE is the scope through which TYPE_DECL is accessed.
20362 LOCATION is the location of the usage point of TYPE_DECL.
20364 This function is a subroutine of
20365 append_type_to_template_for_access_check. */
20368 append_type_to_template_for_access_check_1 (tree t,
20371 location_t location)
20373 qualified_typedef_usage_t typedef_usage;
20376 if (!t || t == error_mark_node)
20379 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20380 || CLASS_TYPE_P (t))
20382 && TREE_CODE (type_decl) == TYPE_DECL
20385 if (!(ti = get_template_info (t)))
20388 gcc_assert (TI_TEMPLATE (ti));
20390 typedef_usage.typedef_decl = type_decl;
20391 typedef_usage.context = scope;
20392 typedef_usage.locus = location;
20394 VEC_safe_push (qualified_typedef_usage_t, gc,
20395 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20399 /* Append TYPE_DECL to the template TEMPL.
20400 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20401 At TEMPL instanciation time, TYPE_DECL will be checked to see
20402 if it can be accessed through SCOPE.
20403 LOCATION is the location of the usage point of TYPE_DECL.
20405 e.g. consider the following code snippet:
20412 template<class U> struct S
20414 C::myint mi; // <-- usage point of the typedef C::myint
20419 At S<char> instantiation time, we need to check the access of C::myint
20420 In other words, we need to check the access of the myint typedef through
20421 the C scope. For that purpose, this function will add the myint typedef
20422 and the scope C through which its being accessed to a list of typedefs
20423 tied to the template S. That list will be walked at template instantiation
20424 time and access check performed on each typedefs it contains.
20425 Note that this particular code snippet should yield an error because
20426 myint is private to C. */
20429 append_type_to_template_for_access_check (tree templ,
20432 location_t location)
20434 qualified_typedef_usage_t *iter;
20437 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20439 /* Make sure we don't append the type to the template twice. */
20440 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20441 get_types_needing_access_check (templ),
20443 if (iter->typedef_decl == type_decl && scope == iter->context)
20446 append_type_to_template_for_access_check_1 (templ, type_decl,
20450 /* Set up the hash tables for template instantiations. */
20453 init_template_processing (void)
20455 decl_specializations = htab_create_ggc (37,
20456 hash_specialization,
20457 eq_specializations,
20459 type_specializations = htab_create_ggc (37,
20460 hash_specialization,
20461 eq_specializations,
20465 /* Print stats about the template hash tables for -fstats. */
20468 print_template_statistics (void)
20470 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20471 "%f collisions\n", (long) htab_size (decl_specializations),
20472 (long) htab_elements (decl_specializations),
20473 htab_collisions (decl_specializations));
20474 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20475 "%f collisions\n", (long) htab_size (type_specializations),
20476 (long) htab_elements (type_specializations),
20477 htab_collisions (type_specializations));
20480 #include "gt-cp-pt.h"