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, 2012
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;
1865 /* In case of explicit specialization, we need to check if
1866 the number of template headers appearing in the specialization
1867 is correct. This is usually done in check_explicit_specialization,
1868 but the check done there cannot be exhaustive when specializing
1869 member functions. Consider the following code:
1871 template <> void A<int>::f(int);
1872 template <> template <> void A<int>::f(int);
1874 Assuming that A<int> is not itself an explicit specialization
1875 already, the first line specializes "f" which is a non-template
1876 member function, whilst the second line specializes "f" which
1877 is a template member function. So both lines are syntactically
1878 correct, and check_explicit_specialization does not reject
1881 Here, we can do better, as we are matching the specialization
1882 against the declarations. We count the number of template
1883 headers, and we check if they match TEMPLATE_COUNT + 1
1884 (TEMPLATE_COUNT is the number of qualifying template classes,
1885 plus there must be another header for the member template
1888 Notice that if header_count is zero, this is not a
1889 specialization but rather a template instantiation, so there
1890 is no check we can perform here. */
1891 if (header_count && header_count != template_count + 1)
1894 /* Check that the number of template arguments at the
1895 innermost level for DECL is the same as for FN. */
1896 if (current_binding_level->kind == sk_template_parms
1897 && !current_binding_level->explicit_spec_p
1898 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1899 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1900 (current_template_parms))))
1903 /* DECL might be a specialization of FN. */
1904 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1905 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1907 /* For a non-static member function, we need to make sure
1908 that the const qualification is the same. Since
1909 get_bindings does not try to merge the "this" parameter,
1910 we must do the comparison explicitly. */
1911 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1912 && !same_type_p (TREE_VALUE (fn_arg_types),
1913 TREE_VALUE (decl_arg_types)))
1916 /* Skip the "this" parameter and, for constructors of
1917 classes with virtual bases, the VTT parameter. A
1918 full specialization of a constructor will have a VTT
1919 parameter, but a template never will. */
1921 = skip_artificial_parms_for (decl, decl_arg_types);
1923 = skip_artificial_parms_for (fn, fn_arg_types);
1925 /* Check that the number of function parameters matches.
1927 template <class T> void f(int i = 0);
1928 template <> void f<int>();
1929 The specialization f<int> is invalid but is not caught
1930 by get_bindings below. */
1931 if (cxx_dialect < cxx11
1932 && list_length (fn_arg_types) != list_length (decl_arg_types))
1935 /* Function templates cannot be specializations; there are
1936 no partial specializations of functions. Therefore, if
1937 the type of DECL does not match FN, there is no
1939 if (tsk == tsk_template)
1941 if (compparms (fn_arg_types, decl_arg_types))
1942 candidates = tree_cons (NULL_TREE, fn, candidates);
1946 /* See whether this function might be a specialization of this
1948 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1951 /* We cannot deduce template arguments that when used to
1952 specialize TMPL will produce DECL. */
1955 if (cxx_dialect >= cxx11)
1957 /* Make sure that the deduced arguments actually work. */
1958 insttype = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
1959 if (insttype == error_mark_node)
1962 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (insttype));
1963 if (!compparms (fn_arg_types, decl_arg_types))
1967 /* Save this template, and the arguments deduced. */
1968 templates = tree_cons (targs, fn, templates);
1970 else if (need_member_template)
1971 /* FN is an ordinary member function, and we need a
1972 specialization of a member template. */
1974 else if (TREE_CODE (fn) != FUNCTION_DECL)
1975 /* We can get IDENTIFIER_NODEs here in certain erroneous
1978 else if (!DECL_FUNCTION_MEMBER_P (fn))
1979 /* This is just an ordinary non-member function. Nothing can
1980 be a specialization of that. */
1982 else if (DECL_ARTIFICIAL (fn))
1983 /* Cannot specialize functions that are created implicitly. */
1987 tree decl_arg_types;
1989 /* This is an ordinary member function. However, since
1990 we're here, we can assume it's enclosing class is a
1991 template class. For example,
1993 template <typename T> struct S { void f(); };
1994 template <> void S<int>::f() {}
1996 Here, S<int>::f is a non-template, but S<int> is a
1997 template class. If FN has the same type as DECL, we
1998 might be in business. */
2000 if (!DECL_TEMPLATE_INFO (fn))
2001 /* Its enclosing class is an explicit specialization
2002 of a template class. This is not a candidate. */
2005 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
2006 TREE_TYPE (TREE_TYPE (fn))))
2007 /* The return types differ. */
2010 /* Adjust the type of DECL in case FN is a static member. */
2011 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
2012 if (DECL_STATIC_FUNCTION_P (fn)
2013 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2014 decl_arg_types = TREE_CHAIN (decl_arg_types);
2016 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2019 candidates = tree_cons (NULL_TREE, fn, candidates);
2023 if (templates && TREE_CHAIN (templates))
2029 It is possible for a specialization with a given function
2030 signature to be instantiated from more than one function
2031 template. In such cases, explicit specification of the
2032 template arguments must be used to uniquely identify the
2033 function template specialization being specialized.
2035 Note that here, there's no suggestion that we're supposed to
2036 determine which of the candidate templates is most
2037 specialized. However, we, also have:
2041 Partial ordering of overloaded function template
2042 declarations is used in the following contexts to select
2043 the function template to which a function template
2044 specialization refers:
2046 -- when an explicit specialization refers to a function
2049 So, we do use the partial ordering rules, at least for now.
2050 This extension can only serve to make invalid programs valid,
2051 so it's safe. And, there is strong anecdotal evidence that
2052 the committee intended the partial ordering rules to apply;
2053 the EDG front end has that behavior, and John Spicer claims
2054 that the committee simply forgot to delete the wording in
2055 [temp.expl.spec]. */
2056 tree tmpl = most_specialized_instantiation (templates);
2057 if (tmpl != error_mark_node)
2060 TREE_CHAIN (templates) = NULL_TREE;
2064 if (templates == NULL_TREE && candidates == NULL_TREE)
2066 error ("template-id %qD for %q+D does not match any template "
2067 "declaration", template_id, decl);
2068 if (header_count && header_count != template_count + 1)
2069 inform (input_location, "saw %d %<template<>%>, need %d for "
2070 "specializing a member function template",
2071 header_count, template_count + 1);
2072 return error_mark_node;
2074 else if ((templates && TREE_CHAIN (templates))
2075 || (candidates && TREE_CHAIN (candidates))
2076 || (templates && candidates))
2078 error ("ambiguous template specialization %qD for %q+D",
2080 candidates = chainon (candidates, templates);
2081 print_candidates (candidates);
2082 return error_mark_node;
2085 /* We have one, and exactly one, match. */
2088 tree fn = TREE_VALUE (candidates);
2089 *targs_out = copy_node (DECL_TI_ARGS (fn));
2090 /* DECL is a re-declaration or partial instantiation of a template
2092 if (TREE_CODE (fn) == TEMPLATE_DECL)
2094 /* It was a specialization of an ordinary member function in a
2096 return DECL_TI_TEMPLATE (fn);
2099 /* It was a specialization of a template. */
2100 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2101 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2103 *targs_out = copy_node (targs);
2104 SET_TMPL_ARGS_LEVEL (*targs_out,
2105 TMPL_ARGS_DEPTH (*targs_out),
2106 TREE_PURPOSE (templates));
2109 *targs_out = TREE_PURPOSE (templates);
2110 return TREE_VALUE (templates);
2113 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2114 but with the default argument values filled in from those in the
2118 copy_default_args_to_explicit_spec_1 (tree spec_types,
2121 tree new_spec_types;
2126 if (spec_types == void_list_node)
2127 return void_list_node;
2129 /* Substitute into the rest of the list. */
2131 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2132 TREE_CHAIN (tmpl_types));
2134 /* Add the default argument for this parameter. */
2135 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2136 TREE_VALUE (spec_types),
2140 /* DECL is an explicit specialization. Replicate default arguments
2141 from the template it specializes. (That way, code like:
2143 template <class T> void f(T = 3);
2144 template <> void f(double);
2147 works, as required.) An alternative approach would be to look up
2148 the correct default arguments at the call-site, but this approach
2149 is consistent with how implicit instantiations are handled. */
2152 copy_default_args_to_explicit_spec (tree decl)
2157 tree new_spec_types;
2161 tree object_type = NULL_TREE;
2162 tree in_charge = NULL_TREE;
2163 tree vtt = NULL_TREE;
2165 /* See if there's anything we need to do. */
2166 tmpl = DECL_TI_TEMPLATE (decl);
2167 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2168 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2169 if (TREE_PURPOSE (t))
2174 old_type = TREE_TYPE (decl);
2175 spec_types = TYPE_ARG_TYPES (old_type);
2177 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2179 /* Remove the this pointer, but remember the object's type for
2181 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2182 spec_types = TREE_CHAIN (spec_types);
2183 tmpl_types = TREE_CHAIN (tmpl_types);
2185 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2187 /* DECL may contain more parameters than TMPL due to the extra
2188 in-charge parameter in constructors and destructors. */
2189 in_charge = spec_types;
2190 spec_types = TREE_CHAIN (spec_types);
2192 if (DECL_HAS_VTT_PARM_P (decl))
2195 spec_types = TREE_CHAIN (spec_types);
2199 /* Compute the merged default arguments. */
2201 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2203 /* Compute the new FUNCTION_TYPE. */
2207 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2212 /* Put the in-charge parameter back. */
2213 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2214 TREE_VALUE (in_charge),
2217 new_type = build_method_type_directly (object_type,
2218 TREE_TYPE (old_type),
2222 new_type = build_function_type (TREE_TYPE (old_type),
2224 new_type = cp_build_type_attribute_variant (new_type,
2225 TYPE_ATTRIBUTES (old_type));
2226 new_type = build_exception_variant (new_type,
2227 TYPE_RAISES_EXCEPTIONS (old_type));
2228 TREE_TYPE (decl) = new_type;
2231 /* Check to see if the function just declared, as indicated in
2232 DECLARATOR, and in DECL, is a specialization of a function
2233 template. We may also discover that the declaration is an explicit
2234 instantiation at this point.
2236 Returns DECL, or an equivalent declaration that should be used
2237 instead if all goes well. Issues an error message if something is
2238 amiss. Returns error_mark_node if the error is not easily
2241 FLAGS is a bitmask consisting of the following flags:
2243 2: The function has a definition.
2244 4: The function is a friend.
2246 The TEMPLATE_COUNT is the number of references to qualifying
2247 template classes that appeared in the name of the function. For
2250 template <class T> struct S { void f(); };
2253 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2254 classes are not counted in the TEMPLATE_COUNT, so that in
2256 template <class T> struct S {};
2257 template <> struct S<int> { void f(); }
2258 template <> void S<int>::f();
2260 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2261 invalid; there should be no template <>.)
2263 If the function is a specialization, it is marked as such via
2264 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2265 is set up correctly, and it is added to the list of specializations
2266 for that template. */
2269 check_explicit_specialization (tree declarator,
2274 int have_def = flags & 2;
2275 int is_friend = flags & 4;
2276 int specialization = 0;
2277 int explicit_instantiation = 0;
2278 int member_specialization = 0;
2279 tree ctype = DECL_CLASS_CONTEXT (decl);
2280 tree dname = DECL_NAME (decl);
2285 if (!processing_specialization)
2288 tsk = tsk_excessive_parms;
2291 tsk = current_tmpl_spec_kind (template_count);
2296 if (processing_specialization)
2299 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2301 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2304 /* This could be something like:
2306 template <class T> void f(T);
2307 class S { friend void f<>(int); } */
2311 /* This case handles bogus declarations like template <>
2312 template <class T> void f<int>(); */
2314 error ("template-id %qD in declaration of primary template",
2321 case tsk_invalid_member_spec:
2322 /* The error has already been reported in
2323 check_specialization_scope. */
2324 return error_mark_node;
2326 case tsk_invalid_expl_inst:
2327 error ("template parameter list used in explicit instantiation");
2333 error ("definition provided for explicit instantiation");
2335 explicit_instantiation = 1;
2338 case tsk_excessive_parms:
2339 case tsk_insufficient_parms:
2340 if (tsk == tsk_excessive_parms)
2341 error ("too many template parameter lists in declaration of %qD",
2343 else if (template_header_count)
2344 error("too few template parameter lists in declaration of %qD", decl);
2346 error("explicit specialization of %qD must be introduced by "
2347 "%<template <>%>", decl);
2351 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2353 member_specialization = 1;
2359 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2361 /* This case handles bogus declarations like template <>
2362 template <class T> void f<int>(); */
2364 if (uses_template_parms (declarator))
2365 error ("function template partial specialization %qD "
2366 "is not allowed", declarator);
2368 error ("template-id %qD in declaration of primary template",
2373 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2374 /* This is a specialization of a member template, without
2375 specialization the containing class. Something like:
2377 template <class T> struct S {
2378 template <class U> void f (U);
2380 template <> template <class U> void S<int>::f(U) {}
2382 That's a specialization -- but of the entire template. */
2390 if (specialization || member_specialization)
2392 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2393 for (; t; t = TREE_CHAIN (t))
2394 if (TREE_PURPOSE (t))
2396 permerror (input_location,
2397 "default argument specified in explicit specialization");
2402 if (specialization || member_specialization || explicit_instantiation)
2404 tree tmpl = NULL_TREE;
2405 tree targs = NULL_TREE;
2407 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2408 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2412 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2417 /* If there is no class context, the explicit instantiation
2418 must be at namespace scope. */
2419 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2421 /* Find the namespace binding, using the declaration
2423 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2425 if (fns == error_mark_node || !is_overloaded_fn (fns))
2427 error ("%qD is not a template function", dname);
2428 fns = error_mark_node;
2432 tree fn = OVL_CURRENT (fns);
2433 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2434 CP_DECL_CONTEXT (fn)))
2435 error ("%qD is not declared in %qD",
2436 decl, current_namespace);
2440 declarator = lookup_template_function (fns, NULL_TREE);
2443 if (declarator == error_mark_node)
2444 return error_mark_node;
2446 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2448 if (!explicit_instantiation)
2449 /* A specialization in class scope. This is invalid,
2450 but the error will already have been flagged by
2451 check_specialization_scope. */
2452 return error_mark_node;
2455 /* It's not valid to write an explicit instantiation in
2458 class C { template void f(); }
2460 This case is caught by the parser. However, on
2463 template class C { void f(); };
2465 (which is invalid) we can get here. The error will be
2472 else if (ctype != NULL_TREE
2473 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2476 /* Find the list of functions in ctype that have the same
2477 name as the declared function. */
2478 tree name = TREE_OPERAND (declarator, 0);
2479 tree fns = NULL_TREE;
2482 if (constructor_name_p (name, ctype))
2484 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2486 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2487 : !CLASSTYPE_DESTRUCTORS (ctype))
2489 /* From [temp.expl.spec]:
2491 If such an explicit specialization for the member
2492 of a class template names an implicitly-declared
2493 special member function (clause _special_), the
2494 program is ill-formed.
2496 Similar language is found in [temp.explicit]. */
2497 error ("specialization of implicitly-declared special member function");
2498 return error_mark_node;
2501 name = is_constructor ? ctor_identifier : dtor_identifier;
2504 if (!DECL_CONV_FN_P (decl))
2506 idx = lookup_fnfields_1 (ctype, name);
2508 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2512 VEC(tree,gc) *methods;
2515 /* For a type-conversion operator, we cannot do a
2516 name-based lookup. We might be looking for `operator
2517 int' which will be a specialization of `operator T'.
2518 So, we find *all* the conversion operators, and then
2519 select from them. */
2522 methods = CLASSTYPE_METHOD_VEC (ctype);
2524 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2525 VEC_iterate (tree, methods, idx, ovl);
2528 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2529 /* There are no more conversion functions. */
2532 /* Glue all these conversion functions together
2533 with those we already have. */
2534 for (; ovl; ovl = OVL_NEXT (ovl))
2535 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2539 if (fns == NULL_TREE)
2541 error ("no member function %qD declared in %qT", name, ctype);
2542 return error_mark_node;
2545 TREE_OPERAND (declarator, 0) = fns;
2548 /* Figure out what exactly is being specialized at this point.
2549 Note that for an explicit instantiation, even one for a
2550 member function, we cannot tell apriori whether the
2551 instantiation is for a member template, or just a member
2552 function of a template class. Even if a member template is
2553 being instantiated, the member template arguments may be
2554 elided if they can be deduced from the rest of the
2556 tmpl = determine_specialization (declarator, decl,
2558 member_specialization,
2562 if (!tmpl || tmpl == error_mark_node)
2563 /* We couldn't figure out what this declaration was
2565 return error_mark_node;
2568 tree gen_tmpl = most_general_template (tmpl);
2570 if (explicit_instantiation)
2572 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2573 is done by do_decl_instantiation later. */
2575 int arg_depth = TMPL_ARGS_DEPTH (targs);
2576 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2578 if (arg_depth > parm_depth)
2580 /* If TMPL is not the most general template (for
2581 example, if TMPL is a friend template that is
2582 injected into namespace scope), then there will
2583 be too many levels of TARGS. Remove some of them
2588 new_targs = make_tree_vec (parm_depth);
2589 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2590 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2591 = TREE_VEC_ELT (targs, i);
2595 return instantiate_template (tmpl, targs, tf_error);
2598 /* If we thought that the DECL was a member function, but it
2599 turns out to be specializing a static member function,
2600 make DECL a static member function as well. */
2601 if (DECL_STATIC_FUNCTION_P (tmpl)
2602 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2603 revert_static_member_fn (decl);
2605 /* If this is a specialization of a member template of a
2606 template class, we want to return the TEMPLATE_DECL, not
2607 the specialization of it. */
2608 if (tsk == tsk_template)
2610 tree result = DECL_TEMPLATE_RESULT (tmpl);
2611 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2612 DECL_INITIAL (result) = NULL_TREE;
2616 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2617 DECL_SOURCE_LOCATION (result)
2618 = DECL_SOURCE_LOCATION (decl);
2619 /* We want to use the argument list specified in the
2620 definition, not in the original declaration. */
2621 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2622 for (parm = DECL_ARGUMENTS (result); parm;
2623 parm = DECL_CHAIN (parm))
2624 DECL_CONTEXT (parm) = result;
2626 return register_specialization (tmpl, gen_tmpl, targs,
2630 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2631 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2633 /* Inherit default function arguments from the template
2634 DECL is specializing. */
2635 copy_default_args_to_explicit_spec (decl);
2637 /* This specialization has the same protection as the
2638 template it specializes. */
2639 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2640 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2642 /* 7.1.1-1 [dcl.stc]
2644 A storage-class-specifier shall not be specified in an
2645 explicit specialization...
2647 The parser rejects these, so unless action is taken here,
2648 explicit function specializations will always appear with
2651 The action recommended by the C++ CWG in response to C++
2652 defect report 605 is to make the storage class and linkage
2653 of the explicit specialization match the templated function:
2655 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2657 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2659 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2660 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2662 /* This specialization has the same linkage and visibility as
2663 the function template it specializes. */
2664 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2665 if (! TREE_PUBLIC (decl))
2667 DECL_INTERFACE_KNOWN (decl) = 1;
2668 DECL_NOT_REALLY_EXTERN (decl) = 1;
2670 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2671 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2673 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2674 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2678 /* If DECL is a friend declaration, declared using an
2679 unqualified name, the namespace associated with DECL may
2680 have been set incorrectly. For example, in:
2682 template <typename T> void f(T);
2684 struct S { friend void f<int>(int); }
2687 we will have set the DECL_CONTEXT for the friend
2688 declaration to N, rather than to the global namespace. */
2689 if (DECL_NAMESPACE_SCOPE_P (decl))
2690 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2692 if (is_friend && !have_def)
2693 /* This is not really a declaration of a specialization.
2694 It's just the name of an instantiation. But, it's not
2695 a request for an instantiation, either. */
2696 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2697 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2698 /* This is indeed a specialization. In case of constructors
2699 and destructors, we need in-charge and not-in-charge
2700 versions in V3 ABI. */
2701 clone_function_decl (decl, /*update_method_vec_p=*/0);
2703 /* Register this specialization so that we can find it
2705 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2712 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2713 parameters. These are represented in the same format used for
2714 DECL_TEMPLATE_PARMS. */
2717 comp_template_parms (const_tree parms1, const_tree parms2)
2722 if (parms1 == parms2)
2725 for (p1 = parms1, p2 = parms2;
2726 p1 != NULL_TREE && p2 != NULL_TREE;
2727 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2729 tree t1 = TREE_VALUE (p1);
2730 tree t2 = TREE_VALUE (p2);
2733 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2734 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2736 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2739 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2741 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2742 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2744 /* If either of the template parameters are invalid, assume
2745 they match for the sake of error recovery. */
2746 if (parm1 == error_mark_node || parm2 == error_mark_node)
2749 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2752 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2753 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2754 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2756 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2761 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2762 /* One set of parameters has more parameters lists than the
2769 /* Determine whether PARM is a parameter pack. */
2772 template_parameter_pack_p (const_tree parm)
2774 /* Determine if we have a non-type template parameter pack. */
2775 if (TREE_CODE (parm) == PARM_DECL)
2776 return (DECL_TEMPLATE_PARM_P (parm)
2777 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2778 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2779 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2781 /* If this is a list of template parameters, we could get a
2782 TYPE_DECL or a TEMPLATE_DECL. */
2783 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2784 parm = TREE_TYPE (parm);
2786 /* Otherwise it must be a type template parameter. */
2787 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2788 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2789 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2792 /* Determine if T is a function parameter pack. */
2795 function_parameter_pack_p (const_tree t)
2797 if (t && TREE_CODE (t) == PARM_DECL)
2798 return FUNCTION_PARAMETER_PACK_P (t);
2802 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2803 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2806 get_function_template_decl (const_tree primary_func_tmpl_inst)
2808 if (! primary_func_tmpl_inst
2809 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2810 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2813 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2816 /* Return true iff the function parameter PARAM_DECL was expanded
2817 from the function parameter pack PACK. */
2820 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2822 if (DECL_ARTIFICIAL (param_decl)
2823 || !function_parameter_pack_p (pack))
2826 /* The parameter pack and its pack arguments have the same
2828 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2831 /* Determine whether ARGS describes a variadic template args list,
2832 i.e., one that is terminated by a template argument pack. */
2835 template_args_variadic_p (tree args)
2840 if (args == NULL_TREE)
2843 args = INNERMOST_TEMPLATE_ARGS (args);
2844 nargs = TREE_VEC_LENGTH (args);
2849 last_parm = TREE_VEC_ELT (args, nargs - 1);
2851 return ARGUMENT_PACK_P (last_parm);
2854 /* Generate a new name for the parameter pack name NAME (an
2855 IDENTIFIER_NODE) that incorporates its */
2858 make_ith_pack_parameter_name (tree name, int i)
2860 /* Munge the name to include the parameter index. */
2861 #define NUMBUF_LEN 128
2862 char numbuf[NUMBUF_LEN];
2866 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2867 newname_len = IDENTIFIER_LENGTH (name)
2868 + strlen (numbuf) + 2;
2869 newname = (char*)alloca (newname_len);
2870 snprintf (newname, newname_len,
2871 "%s#%i", IDENTIFIER_POINTER (name), i);
2872 return get_identifier (newname);
2875 /* Return true if T is a primary function, class or alias template
2879 primary_template_instantiation_p (const_tree t)
2884 if (TREE_CODE (t) == FUNCTION_DECL)
2885 return DECL_LANG_SPECIFIC (t)
2886 && DECL_TEMPLATE_INSTANTIATION (t)
2887 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2888 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2889 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2890 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2892 && TYPE_TEMPLATE_INFO (t)
2893 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
2894 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t)))
2899 /* Return true if PARM is a template template parameter. */
2902 template_template_parameter_p (const_tree parm)
2904 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2907 /* Return the template parameters of T if T is a
2908 primary template instantiation, NULL otherwise. */
2911 get_primary_template_innermost_parameters (const_tree t)
2913 tree parms = NULL, template_info = NULL;
2915 if ((template_info = get_template_info (t))
2916 && primary_template_instantiation_p (t))
2917 parms = INNERMOST_TEMPLATE_PARMS
2918 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2923 /* Return the template parameters of the LEVELth level from the full list
2924 of template parameters PARMS. */
2927 get_template_parms_at_level (tree parms, int level)
2931 || TREE_CODE (parms) != TREE_LIST
2932 || level > TMPL_PARMS_DEPTH (parms))
2935 for (p = parms; p; p = TREE_CHAIN (p))
2936 if (TMPL_PARMS_DEPTH (p) == level)
2942 /* Returns the template arguments of T if T is a template instantiation,
2946 get_template_innermost_arguments (const_tree t)
2948 tree args = NULL, template_info = NULL;
2950 if ((template_info = get_template_info (t))
2951 && TI_ARGS (template_info))
2952 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2957 /* Return the argument pack elements of T if T is a template argument pack,
2961 get_template_argument_pack_elems (const_tree t)
2963 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2964 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2967 return ARGUMENT_PACK_ARGS (t);
2970 /* Structure used to track the progress of find_parameter_packs_r. */
2971 struct find_parameter_pack_data
2973 /* TREE_LIST that will contain all of the parameter packs found by
2975 tree* parameter_packs;
2977 /* Set of AST nodes that have been visited by the traversal. */
2978 struct pointer_set_t *visited;
2981 /* Identifies all of the argument packs that occur in a template
2982 argument and appends them to the TREE_LIST inside DATA, which is a
2983 find_parameter_pack_data structure. This is a subroutine of
2984 make_pack_expansion and uses_parameter_packs. */
2986 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2989 struct find_parameter_pack_data* ppd =
2990 (struct find_parameter_pack_data*)data;
2991 bool parameter_pack_p = false;
2993 /* Handle type aliases/typedefs. */
2996 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
2997 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2999 if (TYPE_TEMPLATE_INFO (t))
3000 cp_walk_tree (&TYPE_TI_ARGS (t),
3001 &find_parameter_packs_r,
3007 /* Identify whether this is a parameter pack or not. */
3008 switch (TREE_CODE (t))
3010 case TEMPLATE_PARM_INDEX:
3011 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3012 parameter_pack_p = true;
3015 case TEMPLATE_TYPE_PARM:
3016 t = TYPE_MAIN_VARIANT (t);
3017 case TEMPLATE_TEMPLATE_PARM:
3018 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3019 parameter_pack_p = true;
3023 if (FUNCTION_PARAMETER_PACK_P (t))
3025 /* We don't want to walk into the type of a PARM_DECL,
3026 because we don't want to see the type parameter pack. */
3028 parameter_pack_p = true;
3033 parameter_pack_p = true;
3036 /* Not a parameter pack. */
3040 if (parameter_pack_p)
3042 /* Add this parameter pack to the list. */
3043 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3047 cp_walk_tree (&TYPE_CONTEXT (t),
3048 &find_parameter_packs_r, ppd, ppd->visited);
3050 /* This switch statement will return immediately if we don't find a
3052 switch (TREE_CODE (t))
3054 case TEMPLATE_PARM_INDEX:
3057 case BOUND_TEMPLATE_TEMPLATE_PARM:
3058 /* Check the template itself. */
3059 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3060 &find_parameter_packs_r, ppd, ppd->visited);
3061 /* Check the template arguments. */
3062 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3067 case TEMPLATE_TYPE_PARM:
3068 case TEMPLATE_TEMPLATE_PARM:
3075 if (TYPE_PTRMEMFUNC_P (t))
3081 if (TYPE_TEMPLATE_INFO (t))
3082 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3083 &find_parameter_packs_r, ppd, ppd->visited);
3090 cp_walk_tree (&TREE_TYPE (t),
3091 &find_parameter_packs_r, ppd, ppd->visited);
3095 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3100 case TYPE_PACK_EXPANSION:
3101 case EXPR_PACK_EXPANSION:
3106 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3111 case IDENTIFIER_NODE:
3112 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3124 /* Determines if the expression or type T uses any parameter packs. */
3126 uses_parameter_packs (tree t)
3128 tree parameter_packs = NULL_TREE;
3129 struct find_parameter_pack_data ppd;
3130 ppd.parameter_packs = ¶meter_packs;
3131 ppd.visited = pointer_set_create ();
3132 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3133 pointer_set_destroy (ppd.visited);
3134 return parameter_packs != NULL_TREE;
3137 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3138 representation a base-class initializer into a parameter pack
3139 expansion. If all goes well, the resulting node will be an
3140 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3143 make_pack_expansion (tree arg)
3146 tree parameter_packs = NULL_TREE;
3147 bool for_types = false;
3148 struct find_parameter_pack_data ppd;
3150 if (!arg || arg == error_mark_node)
3153 if (TREE_CODE (arg) == TREE_LIST)
3155 /* The only time we will see a TREE_LIST here is for a base
3156 class initializer. In this case, the TREE_PURPOSE will be a
3157 _TYPE node (representing the base class expansion we're
3158 initializing) and the TREE_VALUE will be a TREE_LIST
3159 containing the initialization arguments.
3161 The resulting expansion looks somewhat different from most
3162 expansions. Rather than returning just one _EXPANSION, we
3163 return a TREE_LIST whose TREE_PURPOSE is a
3164 TYPE_PACK_EXPANSION containing the bases that will be
3165 initialized. The TREE_VALUE will be identical to the
3166 original TREE_VALUE, which is a list of arguments that will
3167 be passed to each base. We do not introduce any new pack
3168 expansion nodes into the TREE_VALUE (although it is possible
3169 that some already exist), because the TREE_PURPOSE and
3170 TREE_VALUE all need to be expanded together with the same
3171 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3172 resulting TREE_PURPOSE will mention the parameter packs in
3173 both the bases and the arguments to the bases. */
3176 tree parameter_packs = NULL_TREE;
3178 /* Determine which parameter packs will be used by the base
3180 ppd.visited = pointer_set_create ();
3181 ppd.parameter_packs = ¶meter_packs;
3182 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3185 if (parameter_packs == NULL_TREE)
3187 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3188 pointer_set_destroy (ppd.visited);
3189 return error_mark_node;
3192 if (TREE_VALUE (arg) != void_type_node)
3194 /* Collect the sets of parameter packs used in each of the
3195 initialization arguments. */
3196 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3198 /* Determine which parameter packs will be expanded in this
3200 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3205 pointer_set_destroy (ppd.visited);
3207 /* Create the pack expansion type for the base type. */
3208 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3209 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3210 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3212 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3213 they will rarely be compared to anything. */
3214 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3216 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3219 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3222 /* Build the PACK_EXPANSION_* node. */
3224 ? cxx_make_type (TYPE_PACK_EXPANSION)
3225 : make_node (EXPR_PACK_EXPANSION);
3226 SET_PACK_EXPANSION_PATTERN (result, arg);
3227 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3229 /* Propagate type and const-expression information. */
3230 TREE_TYPE (result) = TREE_TYPE (arg);
3231 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3234 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3235 they will rarely be compared to anything. */
3236 SET_TYPE_STRUCTURAL_EQUALITY (result);
3238 /* Determine which parameter packs will be expanded. */
3239 ppd.parameter_packs = ¶meter_packs;
3240 ppd.visited = pointer_set_create ();
3241 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3242 pointer_set_destroy (ppd.visited);
3244 /* Make sure we found some parameter packs. */
3245 if (parameter_packs == NULL_TREE)
3248 error ("expansion pattern %<%T%> contains no argument packs", arg);
3250 error ("expansion pattern %<%E%> contains no argument packs", arg);
3251 return error_mark_node;
3253 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3255 PACK_EXPANSION_LOCAL_P (result) = at_function_scope_p ();
3260 /* Checks T for any "bare" parameter packs, which have not yet been
3261 expanded, and issues an error if any are found. This operation can
3262 only be done on full expressions or types (e.g., an expression
3263 statement, "if" condition, etc.), because we could have expressions like:
3265 foo(f(g(h(args)))...)
3267 where "args" is a parameter pack. check_for_bare_parameter_packs
3268 should not be called for the subexpressions args, h(args),
3269 g(h(args)), or f(g(h(args))), because we would produce erroneous
3272 Returns TRUE and emits an error if there were bare parameter packs,
3273 returns FALSE otherwise. */
3275 check_for_bare_parameter_packs (tree t)
3277 tree parameter_packs = NULL_TREE;
3278 struct find_parameter_pack_data ppd;
3280 if (!processing_template_decl || !t || t == error_mark_node)
3283 if (TREE_CODE (t) == TYPE_DECL)
3286 ppd.parameter_packs = ¶meter_packs;
3287 ppd.visited = pointer_set_create ();
3288 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3289 pointer_set_destroy (ppd.visited);
3291 if (parameter_packs)
3293 error ("parameter packs not expanded with %<...%>:");
3294 while (parameter_packs)
3296 tree pack = TREE_VALUE (parameter_packs);
3297 tree name = NULL_TREE;
3299 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3300 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3301 name = TYPE_NAME (pack);
3302 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3303 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3305 name = DECL_NAME (pack);
3308 inform (input_location, " %qD", name);
3310 inform (input_location, " <anonymous>");
3312 parameter_packs = TREE_CHAIN (parameter_packs);
3321 /* Expand any parameter packs that occur in the template arguments in
3324 expand_template_argument_pack (tree args)
3326 tree result_args = NULL_TREE;
3327 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3328 int num_result_args = -1;
3329 int non_default_args_count = -1;
3331 /* First, determine if we need to expand anything, and the number of
3332 slots we'll need. */
3333 for (in_arg = 0; in_arg < nargs; ++in_arg)
3335 tree arg = TREE_VEC_ELT (args, in_arg);
3336 if (arg == NULL_TREE)
3338 if (ARGUMENT_PACK_P (arg))
3340 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3341 if (num_result_args < 0)
3342 num_result_args = in_arg + num_packed;
3344 num_result_args += num_packed;
3348 if (num_result_args >= 0)
3353 /* If no expansion is necessary, we're done. */
3354 if (num_result_args < 0)
3357 /* Expand arguments. */
3358 result_args = make_tree_vec (num_result_args);
3359 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3360 non_default_args_count =
3361 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3362 for (in_arg = 0; in_arg < nargs; ++in_arg)
3364 tree arg = TREE_VEC_ELT (args, in_arg);
3365 if (ARGUMENT_PACK_P (arg))
3367 tree packed = ARGUMENT_PACK_ARGS (arg);
3368 int i, num_packed = TREE_VEC_LENGTH (packed);
3369 for (i = 0; i < num_packed; ++i, ++out_arg)
3370 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3371 if (non_default_args_count > 0)
3372 non_default_args_count += num_packed;
3376 TREE_VEC_ELT (result_args, out_arg) = arg;
3380 if (non_default_args_count >= 0)
3381 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3385 /* Checks if DECL shadows a template parameter.
3387 [temp.local]: A template-parameter shall not be redeclared within its
3388 scope (including nested scopes).
3390 Emits an error and returns TRUE if the DECL shadows a parameter,
3391 returns FALSE otherwise. */
3394 check_template_shadow (tree decl)
3398 /* If we're not in a template, we can't possibly shadow a template
3400 if (!current_template_parms)
3403 /* Figure out what we're shadowing. */
3404 if (TREE_CODE (decl) == OVERLOAD)
3405 decl = OVL_CURRENT (decl);
3406 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3408 /* If there's no previous binding for this name, we're not shadowing
3409 anything, let alone a template parameter. */
3413 /* If we're not shadowing a template parameter, we're done. Note
3414 that OLDDECL might be an OVERLOAD (or perhaps even an
3415 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3417 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3420 /* We check for decl != olddecl to avoid bogus errors for using a
3421 name inside a class. We check TPFI to avoid duplicate errors for
3422 inline member templates. */
3424 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3427 error ("declaration of %q+#D", decl);
3428 error (" shadows template parm %q+#D", olddecl);
3432 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3433 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3434 template parameters. */
3437 build_template_parm_index (int index,
3444 tree t = make_node (TEMPLATE_PARM_INDEX);
3445 TEMPLATE_PARM_IDX (t) = index;
3446 TEMPLATE_PARM_LEVEL (t) = level;
3447 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3448 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3449 TEMPLATE_PARM_DECL (t) = decl;
3450 TREE_TYPE (t) = type;
3451 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3452 TREE_READONLY (t) = TREE_READONLY (decl);
3457 /* Find the canonical type parameter for the given template type
3458 parameter. Returns the canonical type parameter, which may be TYPE
3459 if no such parameter existed. */
3462 canonical_type_parameter (tree type)
3465 int idx = TEMPLATE_TYPE_IDX (type);
3466 if (!canonical_template_parms)
3467 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3469 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3470 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3472 list = VEC_index (tree, canonical_template_parms, idx);
3473 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3474 list = TREE_CHAIN (list);
3477 return TREE_VALUE (list);
3480 VEC_replace(tree, canonical_template_parms, idx,
3481 tree_cons (NULL_TREE, type,
3482 VEC_index (tree, canonical_template_parms, idx)));
3487 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3488 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3489 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3490 new one is created. */
3493 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3494 tsubst_flags_t complain)
3496 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3497 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3498 != TEMPLATE_PARM_LEVEL (index) - levels)
3499 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3501 tree orig_decl = TEMPLATE_PARM_DECL (index);
3504 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3505 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3506 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3507 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3508 DECL_ARTIFICIAL (decl) = 1;
3509 SET_DECL_TEMPLATE_PARM_P (decl);
3511 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3512 TEMPLATE_PARM_LEVEL (index) - levels,
3513 TEMPLATE_PARM_ORIG_LEVEL (index),
3514 TEMPLATE_PARM_NUM_SIBLINGS (index),
3516 TEMPLATE_PARM_DESCENDANTS (index) = t;
3517 TEMPLATE_PARM_PARAMETER_PACK (t)
3518 = TEMPLATE_PARM_PARAMETER_PACK (index);
3520 /* Template template parameters need this. */
3521 if (TREE_CODE (decl) == TEMPLATE_DECL)
3522 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3523 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3527 return TEMPLATE_PARM_DESCENDANTS (index);
3530 /* Process information from new template parameter PARM and append it
3531 to the LIST being built. This new parameter is a non-type
3532 parameter iff IS_NON_TYPE is true. This new parameter is a
3533 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3534 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3535 parameter list PARM belongs to. This is used used to create a
3536 proper canonical type for the type of PARM that is to be created,
3537 iff PARM is a type. If the size is not known, this parameter shall
3541 process_template_parm (tree list, location_t parm_loc, tree parm,
3542 bool is_non_type, bool is_parameter_pack,
3543 unsigned num_template_parms)
3550 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3551 defval = TREE_PURPOSE (parm);
3555 tree p = tree_last (list);
3557 if (p && TREE_VALUE (p) != error_mark_node)
3560 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3561 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3563 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3573 parm = TREE_VALUE (parm);
3575 SET_DECL_TEMPLATE_PARM_P (parm);
3577 if (TREE_TYPE (parm) == error_mark_node)
3579 err_parm_list = build_tree_list (defval, parm);
3580 TREE_VALUE (err_parm_list) = error_mark_node;
3581 return chainon (list, err_parm_list);
3587 The top-level cv-qualifiers on the template-parameter are
3588 ignored when determining its type. */
3589 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3590 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3592 err_parm_list = build_tree_list (defval, parm);
3593 TREE_VALUE (err_parm_list) = error_mark_node;
3594 return chainon (list, err_parm_list);
3597 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3599 /* This template parameter is not a parameter pack, but it
3600 should be. Complain about "bare" parameter packs. */
3601 check_for_bare_parameter_packs (TREE_TYPE (parm));
3603 /* Recover by calling this a parameter pack. */
3604 is_parameter_pack = true;
3608 /* A template parameter is not modifiable. */
3609 TREE_CONSTANT (parm) = 1;
3610 TREE_READONLY (parm) = 1;
3611 decl = build_decl (parm_loc,
3612 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3613 TREE_CONSTANT (decl) = 1;
3614 TREE_READONLY (decl) = 1;
3615 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3616 = build_template_parm_index (idx, processing_template_decl,
3617 processing_template_decl,
3619 decl, TREE_TYPE (parm));
3621 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3622 = is_parameter_pack;
3627 parm = TREE_VALUE (TREE_VALUE (parm));
3629 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3631 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3632 /* This is for distinguishing between real templates and template
3633 template parameters */
3634 TREE_TYPE (parm) = t;
3635 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3640 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3641 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3642 decl = build_decl (parm_loc,
3643 TYPE_DECL, parm, t);
3646 TYPE_NAME (t) = decl;
3647 TYPE_STUB_DECL (t) = decl;
3649 TEMPLATE_TYPE_PARM_INDEX (t)
3650 = build_template_parm_index (idx, processing_template_decl,
3651 processing_template_decl,
3653 decl, TREE_TYPE (parm));
3654 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3655 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3657 DECL_ARTIFICIAL (decl) = 1;
3658 SET_DECL_TEMPLATE_PARM_P (decl);
3660 parm = build_tree_list (defval, parm);
3661 return chainon (list, parm);
3664 /* The end of a template parameter list has been reached. Process the
3665 tree list into a parameter vector, converting each parameter into a more
3666 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3670 end_template_parm_list (tree parms)
3674 tree saved_parmlist = make_tree_vec (list_length (parms));
3676 current_template_parms
3677 = tree_cons (size_int (processing_template_decl),
3678 saved_parmlist, current_template_parms);
3680 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3682 next = TREE_CHAIN (parm);
3683 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3684 TREE_CHAIN (parm) = NULL_TREE;
3687 --processing_template_parmlist;
3689 return saved_parmlist;
3692 /* Create a new type almost identical to TYPE but which has the
3693 following differences:
3695 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3696 template sibling parameters of T.
3698 2/ T has a new canonical type that matches the new number
3701 3/ From now on, T is going to be what lookups referring to the
3702 name of TYPE will return. No lookup should return TYPE anymore.
3704 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3706 This is a subroutine of fixup_template_parms. */
3709 fixup_template_type_parm_type (tree type, int num_parms)
3711 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3713 /* This is the decl which name is inserted into the symbol table for
3714 the template parm type. So whenever we lookup the type name, this
3715 is the DECL we get. */
3718 /* Do not fix up the type twice. */
3719 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3722 t = copy_type (type);
3723 decl = TYPE_NAME (t);
3725 TYPE_MAIN_VARIANT (t) = t;
3726 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3727 TYPE_POINTER_TO (t) = 0;
3728 TYPE_REFERENCE_TO (t) = 0;
3730 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3731 TEMPLATE_PARM_LEVEL (orig_idx),
3732 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3735 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3736 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3737 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3739 TYPE_STUB_DECL (t) = decl;
3740 TEMPLATE_TYPE_DECL (t) = decl;
3741 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3742 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3744 /* Update the type associated to the type name stored in the symbol
3745 table. Now, whenever the type name is looked up, the resulting
3746 type is properly fixed up. */
3747 TREE_TYPE (decl) = t;
3749 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3754 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3755 identical to I, but that is fixed up as to:
3757 1/ carry the number of sibling parms (NUM_PARMS) of the template
3758 parm represented by I.
3760 2/ replace all references to template parm types declared before I
3761 (in the same template parm list as I) by references to template
3762 parm types contained in ARGS. ARGS should contain the list of
3763 template parms that have been fixed up so far, in a form suitable
3764 to be passed to tsubst.
3766 This is a subroutine of fixup_template_parms. */
3769 fixup_template_parm_index (tree i, tree args, int num_parms)
3771 tree index, decl, type;
3774 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3775 /* Do not fix up the index twice. */
3776 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3779 decl = TEMPLATE_PARM_DECL (i);
3780 type = TREE_TYPE (decl);
3782 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3783 TEMPLATE_PARM_LEVEL (i),
3784 TEMPLATE_PARM_ORIG_LEVEL (i),
3788 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3789 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3791 type = tsubst (type, args, tf_none, NULL_TREE);
3793 TREE_TYPE (decl) = type;
3794 TREE_TYPE (index) = type;
3800 This is a subroutine of fixup_template_parms.
3802 It computes the canonical type of the type of the template
3803 parameter PARM_DESC and update all references to that type so that
3804 they use the newly computed canonical type. No access check is
3805 performed during the fixup. PARM_DESC is a TREE_LIST which
3806 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3807 default argument of the template parm if any. IDX is the index of
3808 the template parameter, starting at 0. NUM_PARMS is the number of
3809 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3810 TREE_VEC containing the full set of template parameters in a form
3811 suitable to be passed to substs functions as their ARGS
3812 argument. This is what current_template_args returns for a given
3813 template. The innermost vector of args in ARGLIST is the set of
3814 template parms that have been fixed up so far. This function adds
3815 the fixed up parameter into that vector. */
3818 fixup_template_parm (tree parm_desc,
3823 tree parm = TREE_VALUE (parm_desc);
3824 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3826 push_deferring_access_checks (dk_no_check);
3828 if (TREE_CODE (parm) == TYPE_DECL)
3830 /* PARM is a template type parameter. Fix up its type, add
3831 the fixed-up template parm to the vector of fixed-up
3832 template parms so far, and substitute the fixed-up
3833 template parms into the default argument of this
3836 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3837 TREE_TYPE (parm) = t;
3839 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3841 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3843 /* PARM is a template template parameter. This is going to
3845 tree tparms, targs, innermost_args, t;
3848 /* First, fix up the parms of the template template parm
3849 because the parms are involved in defining the new canonical
3850 type of the template template parm. */
3852 /* So we need to substitute the template parm types that have
3853 been fixed up so far into the template parms of this template
3854 template parm. E.g, consider this:
3856 template<class T, template<T u> class TT> class S;
3858 In this case we want to substitute T into the
3859 template parameters of TT.
3861 So let's walk the template parms of PARM here, and
3862 tsubst ARGLIST into into each of the template
3865 /* For this substitution we need to build the full set of
3866 template parameters and use that as arguments for the
3867 tsubsting function. */
3868 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3870 /* This will contain the innermost parms of PARM into which
3871 we have substituted so far. */
3872 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3873 targs = add_to_template_args (arglist, innermost_args);
3874 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3878 parameter = TREE_VEC_ELT (tparms, j);
3880 /* INNERMOST_ARGS needs to have at least the same number
3881 of elements as the index PARAMETER, ortherwise
3882 tsubsting into PARAMETER will result in partially
3883 instantiating it, reducing its tempate parm
3884 level. Let's tactically fill INNERMOST_ARGS for that
3886 TREE_VEC_ELT (innermost_args, j) =
3887 template_parm_to_arg (parameter);
3889 fixup_template_parm (parameter, j,
3890 TREE_VEC_LENGTH (tparms),
3894 /* Now fix up the type of the template template parm. */
3896 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3897 TREE_TYPE (parm) = t;
3899 TREE_VEC_ELT (fixedup_args, idx) =
3900 template_parm_to_arg (parm_desc);
3902 else if (TREE_CODE (parm) == PARM_DECL)
3904 /* PARM is a non-type template parameter. We need to:
3906 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3907 proper number of sibling parameters.
3909 * Make lookups of the template parameter return a reference
3910 to the fixed-up index. No lookup should return references
3911 to the former index anymore.
3913 * Substitute the template parms that got fixed up so far
3915 * into the type of PARM. */
3917 tree index = DECL_INITIAL (parm);
3919 /* PUSHED_DECL is the decl added to the symbol table with
3920 the name of the parameter. E,g:
3922 template<class T, T u> //#0
3923 auto my_function(T t) -> decltype(u); //#1
3925 Here, when looking up u at //#1, we get the decl of u
3926 resulting from the declaration in #0. This is what
3927 PUSHED_DECL is. We need to replace the reference to the
3928 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3929 fixed-up TEMPLATE_PARM_INDEX. */
3930 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3932 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3933 fixup the type of PUSHED_DECL as well and luckily
3934 fixup_template_parm_index does it for us too. */
3935 tree fixed_up_index =
3936 fixup_template_parm_index (index, arglist, num_parms);
3938 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3940 /* Add this fixed up PARM to the template parms we've fixed
3941 up so far and use that to substitute the fixed-up
3942 template parms into the type of PARM. */
3943 TREE_VEC_ELT (fixedup_args, idx) =
3944 template_parm_to_arg (parm_desc);
3945 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3946 tf_none, NULL_TREE);
3949 TREE_PURPOSE (parm_desc) =
3950 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3951 arglist, tf_none, parm);
3953 pop_deferring_access_checks ();
3956 /* Walk the current template parms and properly compute the canonical
3957 types of the dependent types created during
3958 cp_parser_template_parameter_list. */
3961 fixup_template_parms (void)
3968 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3969 if (parameter_vec == NULL_TREE)
3972 num_parms = TREE_VEC_LENGTH (parameter_vec);
3974 /* This vector contains the current innermost template parms that
3975 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3976 to be passed to tsubst* functions as their ARGS argument. */
3977 fixedup_args = make_tree_vec (num_parms);
3979 /* This vector contains the full set of template parms in a form
3980 suitable to be passed to substs functions as their ARGS
3982 arglist = current_template_args ();
3983 arglist = add_outermost_template_args (arglist, fixedup_args);
3985 /* Let's do the proper fixup now. */
3986 for (i = 0; i < num_parms; ++i)
3987 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3988 i, num_parms, arglist);
3991 /* end_template_decl is called after a template declaration is seen. */
3994 end_template_decl (void)
3996 reset_specialization ();
3998 if (! processing_template_decl)
4001 /* This matches the pushlevel in begin_template_parm_list. */
4004 --processing_template_decl;
4005 current_template_parms = TREE_CHAIN (current_template_parms);
4008 /* Takes a TREE_LIST representing a template parameter and convert it
4009 into an argument suitable to be passed to the type substitution
4010 functions. Note that If the TREE_LIST contains an error_mark
4011 node, the returned argument is error_mark_node. */
4014 template_parm_to_arg (tree t)
4018 || TREE_CODE (t) != TREE_LIST)
4021 if (error_operand_p (TREE_VALUE (t)))
4022 return error_mark_node;
4026 if (TREE_CODE (t) == TYPE_DECL
4027 || TREE_CODE (t) == TEMPLATE_DECL)
4031 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4033 /* Turn this argument into a TYPE_ARGUMENT_PACK
4034 with a single element, which expands T. */
4035 tree vec = make_tree_vec (1);
4036 #ifdef ENABLE_CHECKING
4037 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4038 (vec, TREE_VEC_LENGTH (vec));
4040 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4042 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4043 SET_ARGUMENT_PACK_ARGS (t, vec);
4048 t = DECL_INITIAL (t);
4050 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4052 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4053 with a single element, which expands T. */
4054 tree vec = make_tree_vec (1);
4055 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4056 #ifdef ENABLE_CHECKING
4057 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4058 (vec, TREE_VEC_LENGTH (vec));
4060 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4062 t = make_node (NONTYPE_ARGUMENT_PACK);
4063 SET_ARGUMENT_PACK_ARGS (t, vec);
4064 TREE_TYPE (t) = type;
4070 /* This function returns TRUE if PARM_PACK is a template parameter
4071 pack and if ARG_PACK is what template_parm_to_arg returned when
4072 passed PARM_PACK. */
4075 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4077 /* For clarity in the comments below let's use the representation
4078 argument_pack<elements>' to denote an argument pack and its
4081 In the 'if' block below, we want to detect cases where
4082 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4083 check if ARG_PACK is an argument pack which sole element is
4084 the expansion of PARM_PACK. That argument pack is typically
4085 created by template_parm_to_arg when passed a parameter
4089 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4090 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4092 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4093 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4094 /* So we have an argument_pack<P...>. We want to test if P
4095 is actually PARM_PACK. We will not use cp_tree_equal to
4096 test P and PARM_PACK because during type fixup (by
4097 fixup_template_parm) P can be a pre-fixup version of a
4098 type and PARM_PACK be its post-fixup version.
4099 cp_tree_equal would consider them as different even
4100 though we would want to consider them compatible for our
4101 precise purpose here.
4103 Thus we are going to consider that P and PARM_PACK are
4104 compatible if they have the same DECL. */
4105 if ((/* If ARG_PACK is a type parameter pack named by the
4106 same DECL as parm_pack ... */
4108 && TYPE_P (parm_pack)
4109 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4110 /* ... or if PARM_PACK is a non-type parameter named by the
4111 same DECL as ARG_PACK. Note that PARM_PACK being a
4112 non-type parameter means it's either a PARM_DECL or a
4113 TEMPLATE_PARM_INDEX. */
4114 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4115 && ((TREE_CODE (parm_pack) == PARM_DECL
4116 && (TEMPLATE_PARM_DECL (pattern)
4117 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4118 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4119 && (TEMPLATE_PARM_DECL (pattern)
4120 == TEMPLATE_PARM_DECL (parm_pack))))))
4121 && template_parameter_pack_p (pattern))
4127 /* Within the declaration of a template, return all levels of template
4128 parameters that apply. The template parameters are represented as
4129 a TREE_VEC, in the form documented in cp-tree.h for template
4133 current_template_args (void)
4136 tree args = NULL_TREE;
4137 int length = TMPL_PARMS_DEPTH (current_template_parms);
4140 /* If there is only one level of template parameters, we do not
4141 create a TREE_VEC of TREE_VECs. Instead, we return a single
4142 TREE_VEC containing the arguments. */
4144 args = make_tree_vec (length);
4146 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4148 tree a = copy_node (TREE_VALUE (header));
4151 TREE_TYPE (a) = NULL_TREE;
4152 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4153 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4155 #ifdef ENABLE_CHECKING
4156 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4160 TREE_VEC_ELT (args, --l) = a;
4165 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4166 /* This can happen for template parms of a template template
4169 template<template<class T, class U> class TT> struct S;
4171 Consider the level of the parms of TT; T and U both have
4172 level 2; TT has no template parm of level 1. So in this case
4173 the first element of full_template_args is NULL_TREE. If we
4174 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4175 of 2. This will make tsubst wrongly consider that T and U
4176 have level 1. Instead, let's create a dummy vector as the
4177 first element of full_template_args so that TMPL_ARG_DEPTH
4178 returns the correct depth for args. */
4179 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4183 /* Update the declared TYPE by doing any lookups which were thought to be
4184 dependent, but are not now that we know the SCOPE of the declarator. */
4187 maybe_update_decl_type (tree orig_type, tree scope)
4189 tree type = orig_type;
4191 if (type == NULL_TREE)
4194 if (TREE_CODE (orig_type) == TYPE_DECL)
4195 type = TREE_TYPE (type);
4197 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4198 && dependent_type_p (type)
4199 /* Don't bother building up the args in this case. */
4200 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4202 /* tsubst in the args corresponding to the template parameters,
4203 including auto if present. Most things will be unchanged, but
4204 make_typename_type and tsubst_qualified_id will resolve
4205 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4206 tree args = current_template_args ();
4207 tree auto_node = type_uses_auto (type);
4211 tree auto_vec = make_tree_vec (1);
4212 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4213 args = add_to_template_args (args, auto_vec);
4215 pushed = push_scope (scope);
4216 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4221 if (type == error_mark_node)
4224 if (TREE_CODE (orig_type) == TYPE_DECL)
4226 if (same_type_p (type, TREE_TYPE (orig_type)))
4229 type = TYPE_NAME (type);
4234 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4235 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4236 a member template. Used by push_template_decl below. */
4239 build_template_decl (tree decl, tree parms, bool member_template_p)
4241 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4242 DECL_TEMPLATE_PARMS (tmpl) = parms;
4243 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4244 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4245 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4250 struct template_parm_data
4252 /* The level of the template parameters we are currently
4256 /* The index of the specialization argument we are currently
4260 /* An array whose size is the number of template parameters. The
4261 elements are nonzero if the parameter has been used in any one
4262 of the arguments processed so far. */
4265 /* An array whose size is the number of template arguments. The
4266 elements are nonzero if the argument makes use of template
4267 parameters of this level. */
4268 int* arg_uses_template_parms;
4271 /* Subroutine of push_template_decl used to see if each template
4272 parameter in a partial specialization is used in the explicit
4273 argument list. If T is of the LEVEL given in DATA (which is
4274 treated as a template_parm_data*), then DATA->PARMS is marked
4278 mark_template_parm (tree t, void* data)
4282 struct template_parm_data* tpd = (struct template_parm_data*) data;
4284 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4286 level = TEMPLATE_PARM_LEVEL (t);
4287 idx = TEMPLATE_PARM_IDX (t);
4291 level = TEMPLATE_TYPE_LEVEL (t);
4292 idx = TEMPLATE_TYPE_IDX (t);
4295 if (level == tpd->level)
4297 tpd->parms[idx] = 1;
4298 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4301 /* Return zero so that for_each_template_parm will continue the
4302 traversal of the tree; we want to mark *every* template parm. */
4306 /* Process the partial specialization DECL. */
4309 process_partial_specialization (tree decl)
4311 tree type = TREE_TYPE (decl);
4312 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4313 tree specargs = CLASSTYPE_TI_ARGS (type);
4314 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4315 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4318 int nargs = TREE_VEC_LENGTH (inner_args);
4321 bool did_error_intro = false;
4322 struct template_parm_data tpd;
4323 struct template_parm_data tpd2;
4325 gcc_assert (current_template_parms);
4327 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4328 ntparms = TREE_VEC_LENGTH (inner_parms);
4330 /* We check that each of the template parameters given in the
4331 partial specialization is used in the argument list to the
4332 specialization. For example:
4334 template <class T> struct S;
4335 template <class T> struct S<T*>;
4337 The second declaration is OK because `T*' uses the template
4338 parameter T, whereas
4340 template <class T> struct S<int>;
4342 is no good. Even trickier is:
4353 The S2<T> declaration is actually invalid; it is a
4354 full-specialization. Of course,
4357 struct S2<T (*)(U)>;
4359 or some such would have been OK. */
4360 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4361 tpd.parms = XALLOCAVEC (int, ntparms);
4362 memset (tpd.parms, 0, sizeof (int) * ntparms);
4364 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4365 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4366 for (i = 0; i < nargs; ++i)
4368 tpd.current_arg = i;
4369 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4370 &mark_template_parm,
4373 /*include_nondeduced_p=*/false);
4375 for (i = 0; i < ntparms; ++i)
4376 if (tpd.parms[i] == 0)
4378 /* One of the template parms was not used in the
4380 if (!did_error_intro)
4382 error ("template parameters not used in partial specialization:");
4383 did_error_intro = true;
4386 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4389 if (did_error_intro)
4390 return error_mark_node;
4392 /* [temp.class.spec]
4394 The argument list of the specialization shall not be identical to
4395 the implicit argument list of the primary template. */
4396 if (comp_template_args
4398 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4400 error ("partial specialization %qT does not specialize any template arguments", type);
4402 /* [temp.class.spec]
4404 A partially specialized non-type argument expression shall not
4405 involve template parameters of the partial specialization except
4406 when the argument expression is a simple identifier.
4408 The type of a template parameter corresponding to a specialized
4409 non-type argument shall not be dependent on a parameter of the
4412 Also, we verify that pack expansions only occur at the
4413 end of the argument list. */
4414 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4416 for (i = 0; i < nargs; ++i)
4418 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4419 tree arg = TREE_VEC_ELT (inner_args, i);
4420 tree packed_args = NULL_TREE;
4423 if (ARGUMENT_PACK_P (arg))
4425 /* Extract the arguments from the argument pack. We'll be
4426 iterating over these in the following loop. */
4427 packed_args = ARGUMENT_PACK_ARGS (arg);
4428 len = TREE_VEC_LENGTH (packed_args);
4431 for (j = 0; j < len; j++)
4434 /* Get the Jth argument in the parameter pack. */
4435 arg = TREE_VEC_ELT (packed_args, j);
4437 if (PACK_EXPANSION_P (arg))
4439 /* Pack expansions must come at the end of the
4441 if ((packed_args && j < len - 1)
4442 || (!packed_args && i < nargs - 1))
4444 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4445 error ("parameter pack argument %qE must be at the "
4446 "end of the template argument list", arg);
4448 error ("parameter pack argument %qT must be at the "
4449 "end of the template argument list", arg);
4453 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4454 /* We only care about the pattern. */
4455 arg = PACK_EXPANSION_PATTERN (arg);
4457 if (/* These first two lines are the `non-type' bit. */
4459 && TREE_CODE (arg) != TEMPLATE_DECL
4460 /* This next line is the `argument expression is not just a
4461 simple identifier' condition and also the `specialized
4462 non-type argument' bit. */
4463 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4465 if ((!packed_args && tpd.arg_uses_template_parms[i])
4466 || (packed_args && uses_template_parms (arg)))
4467 error ("template argument %qE involves template parameter(s)",
4471 /* Look at the corresponding template parameter,
4472 marking which template parameters its type depends
4474 tree type = TREE_TYPE (parm);
4478 /* We haven't yet initialized TPD2. Do so now. */
4479 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4480 /* The number of parameters here is the number in the
4481 main template, which, as checked in the assertion
4483 tpd2.parms = XALLOCAVEC (int, nargs);
4485 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4488 /* Mark the template parameters. But this time, we're
4489 looking for the template parameters of the main
4490 template, not in the specialization. */
4491 tpd2.current_arg = i;
4492 tpd2.arg_uses_template_parms[i] = 0;
4493 memset (tpd2.parms, 0, sizeof (int) * nargs);
4494 for_each_template_parm (type,
4495 &mark_template_parm,
4498 /*include_nondeduced_p=*/false);
4500 if (tpd2.arg_uses_template_parms [i])
4502 /* The type depended on some template parameters.
4503 If they are fully specialized in the
4504 specialization, that's OK. */
4507 for (j = 0; j < nargs; ++j)
4508 if (tpd2.parms[j] != 0
4509 && tpd.arg_uses_template_parms [j])
4512 error_n (input_location, count,
4513 "type %qT of template argument %qE depends "
4514 "on a template parameter",
4515 "type %qT of template argument %qE depends "
4516 "on template parameters",
4525 /* We should only get here once. */
4526 gcc_assert (!COMPLETE_TYPE_P (type));
4528 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4529 = tree_cons (specargs, inner_parms,
4530 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4531 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4533 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4534 inst = TREE_CHAIN (inst))
4536 tree inst_type = TREE_VALUE (inst);
4537 if (COMPLETE_TYPE_P (inst_type)
4538 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4540 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4541 if (spec && TREE_TYPE (spec) == type)
4542 permerror (input_location,
4543 "partial specialization of %qT after instantiation "
4544 "of %qT", type, inst_type);
4551 /* Check that a template declaration's use of default arguments and
4552 parameter packs is not invalid. Here, PARMS are the template
4553 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4554 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4558 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4559 declaration (but not a definition); 1 indicates a declaration, 2
4560 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4561 emitted for extraneous default arguments.
4563 Returns TRUE if there were no errors found, FALSE otherwise. */
4566 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4567 int is_partial, int is_friend_decl)
4570 int last_level_to_check;
4572 bool no_errors = true;
4576 A default template-argument shall not be specified in a
4577 function template declaration or a function template definition, nor
4578 in the template-parameter-list of the definition of a member of a
4581 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4582 /* You can't have a function template declaration in a local
4583 scope, nor you can you define a member of a class template in a
4587 if (current_class_type
4588 && !TYPE_BEING_DEFINED (current_class_type)
4589 && DECL_LANG_SPECIFIC (decl)
4590 && DECL_DECLARES_FUNCTION_P (decl)
4591 /* If this is either a friend defined in the scope of the class
4592 or a member function. */
4593 && (DECL_FUNCTION_MEMBER_P (decl)
4594 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4595 : DECL_FRIEND_CONTEXT (decl)
4596 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4598 /* And, if it was a member function, it really was defined in
4599 the scope of the class. */
4600 && (!DECL_FUNCTION_MEMBER_P (decl)
4601 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4602 /* We already checked these parameters when the template was
4603 declared, so there's no need to do it again now. This function
4604 was defined in class scope, but we're processing it's body now
4605 that the class is complete. */
4608 /* Core issue 226 (C++0x only): the following only applies to class
4610 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4614 If a template-parameter has a default template-argument, all
4615 subsequent template-parameters shall have a default
4616 template-argument supplied. */
4617 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4619 tree inner_parms = TREE_VALUE (parm_level);
4620 int ntparms = TREE_VEC_LENGTH (inner_parms);
4621 int seen_def_arg_p = 0;
4624 for (i = 0; i < ntparms; ++i)
4626 tree parm = TREE_VEC_ELT (inner_parms, i);
4628 if (parm == error_mark_node)
4631 if (TREE_PURPOSE (parm))
4633 else if (seen_def_arg_p
4634 && !template_parameter_pack_p (TREE_VALUE (parm)))
4636 error ("no default argument for %qD", TREE_VALUE (parm));
4637 /* For better subsequent error-recovery, we indicate that
4638 there should have been a default argument. */
4639 TREE_PURPOSE (parm) = error_mark_node;
4645 /* Don't complain about an enclosing partial
4647 && parm_level == parms
4648 && TREE_CODE (decl) == TYPE_DECL
4650 && template_parameter_pack_p (TREE_VALUE (parm)))
4652 /* A primary class template can only have one
4653 parameter pack, at the end of the template
4656 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4657 error ("parameter pack %qE must be at the end of the"
4658 " template parameter list", TREE_VALUE (parm));
4660 error ("parameter pack %qT must be at the end of the"
4661 " template parameter list",
4662 TREE_TYPE (TREE_VALUE (parm)));
4664 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4672 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4676 /* For an ordinary class template, default template arguments are
4677 allowed at the innermost level, e.g.:
4678 template <class T = int>
4680 but, in a partial specialization, they're not allowed even
4681 there, as we have in [temp.class.spec]:
4683 The template parameter list of a specialization shall not
4684 contain default template argument values.
4686 So, for a partial specialization, or for a function template
4687 (in C++98/C++03), we look at all of them. */
4690 /* But, for a primary class template that is not a partial
4691 specialization we look at all template parameters except the
4693 parms = TREE_CHAIN (parms);
4695 /* Figure out what error message to issue. */
4696 if (is_friend_decl == 2)
4697 msg = G_("default template arguments may not be used in function template "
4698 "friend re-declaration");
4699 else if (is_friend_decl)
4700 msg = G_("default template arguments may not be used in function template "
4701 "friend declarations");
4702 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4703 msg = G_("default template arguments may not be used in function templates "
4704 "without -std=c++11 or -std=gnu++11");
4705 else if (is_partial)
4706 msg = G_("default template arguments may not be used in "
4707 "partial specializations");
4709 msg = G_("default argument for template parameter for class enclosing %qD");
4711 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4712 /* If we're inside a class definition, there's no need to
4713 examine the parameters to the class itself. On the one
4714 hand, they will be checked when the class is defined, and,
4715 on the other, default arguments are valid in things like:
4716 template <class T = double>
4717 struct S { template <class U> void f(U); };
4718 Here the default argument for `S' has no bearing on the
4719 declaration of `f'. */
4720 last_level_to_check = template_class_depth (current_class_type) + 1;
4722 /* Check everything. */
4723 last_level_to_check = 0;
4725 for (parm_level = parms;
4726 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4727 parm_level = TREE_CHAIN (parm_level))
4729 tree inner_parms = TREE_VALUE (parm_level);
4733 ntparms = TREE_VEC_LENGTH (inner_parms);
4734 for (i = 0; i < ntparms; ++i)
4736 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4739 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4744 if (is_friend_decl == 2)
4751 /* Clear out the default argument so that we are not
4753 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4757 /* At this point, if we're still interested in issuing messages,
4758 they must apply to classes surrounding the object declared. */
4760 msg = G_("default argument for template parameter for class "
4767 /* Worker for push_template_decl_real, called via
4768 for_each_template_parm. DATA is really an int, indicating the
4769 level of the parameters we are interested in. If T is a template
4770 parameter of that level, return nonzero. */
4773 template_parm_this_level_p (tree t, void* data)
4775 int this_level = *(int *)data;
4778 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4779 level = TEMPLATE_PARM_LEVEL (t);
4781 level = TEMPLATE_TYPE_LEVEL (t);
4782 return level == this_level;
4785 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4786 parameters given by current_template_args, or reuses a
4787 previously existing one, if appropriate. Returns the DECL, or an
4788 equivalent one, if it is replaced via a call to duplicate_decls.
4790 If IS_FRIEND is true, DECL is a friend declaration. */
4793 push_template_decl_real (tree decl, bool is_friend)
4801 int new_template_p = 0;
4802 /* True if the template is a member template, in the sense of
4804 bool member_template_p = false;
4806 if (decl == error_mark_node || !current_template_parms)
4807 return error_mark_node;
4809 /* See if this is a partial specialization. */
4810 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4811 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4812 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4814 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4818 /* For a friend, we want the context of the friend function, not
4819 the type of which it is a friend. */
4820 ctx = CP_DECL_CONTEXT (decl);
4821 else if (CP_DECL_CONTEXT (decl)
4822 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4823 /* In the case of a virtual function, we want the class in which
4825 ctx = CP_DECL_CONTEXT (decl);
4827 /* Otherwise, if we're currently defining some class, the DECL
4828 is assumed to be a member of the class. */
4829 ctx = current_scope ();
4831 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4834 if (!DECL_CONTEXT (decl))
4835 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4837 /* See if this is a primary template. */
4838 if (is_friend && ctx)
4839 /* A friend template that specifies a class context, i.e.
4840 template <typename T> friend void A<T>::f();
4844 primary = template_parm_scope_p ();
4848 if (DECL_CLASS_SCOPE_P (decl))
4849 member_template_p = true;
4850 if (TREE_CODE (decl) == TYPE_DECL
4851 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4853 error ("template class without a name");
4854 return error_mark_node;
4856 else if (TREE_CODE (decl) == FUNCTION_DECL)
4858 if (DECL_DESTRUCTOR_P (decl))
4862 A destructor shall not be a member template. */
4863 error ("destructor %qD declared as member template", decl);
4864 return error_mark_node;
4866 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4867 && (!prototype_p (TREE_TYPE (decl))
4868 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4869 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4870 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4871 == void_list_node)))
4873 /* [basic.stc.dynamic.allocation]
4875 An allocation function can be a function
4876 template. ... Template allocation functions shall
4877 have two or more parameters. */
4878 error ("invalid template declaration of %qD", decl);
4879 return error_mark_node;
4882 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4883 && CLASS_TYPE_P (TREE_TYPE (decl)))
4885 else if (TREE_CODE (decl) == TYPE_DECL
4886 && TYPE_DECL_ALIAS_P (decl))
4887 /* alias-declaration */
4888 gcc_assert (!DECL_ARTIFICIAL (decl));
4891 error ("template declaration of %q#D", decl);
4892 return error_mark_node;
4896 /* Check to see that the rules regarding the use of default
4897 arguments are not being violated. */
4898 check_default_tmpl_args (decl, current_template_parms,
4899 primary, is_partial, /*is_friend_decl=*/0);
4901 /* Ensure that there are no parameter packs in the type of this
4902 declaration that have not been expanded. */
4903 if (TREE_CODE (decl) == FUNCTION_DECL)
4905 /* Check each of the arguments individually to see if there are
4906 any bare parameter packs. */
4907 tree type = TREE_TYPE (decl);
4908 tree arg = DECL_ARGUMENTS (decl);
4909 tree argtype = TYPE_ARG_TYPES (type);
4911 while (arg && argtype)
4913 if (!FUNCTION_PARAMETER_PACK_P (arg)
4914 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4916 /* This is a PARM_DECL that contains unexpanded parameter
4917 packs. We have already complained about this in the
4918 check_for_bare_parameter_packs call, so just replace
4919 these types with ERROR_MARK_NODE. */
4920 TREE_TYPE (arg) = error_mark_node;
4921 TREE_VALUE (argtype) = error_mark_node;
4924 arg = DECL_CHAIN (arg);
4925 argtype = TREE_CHAIN (argtype);
4928 /* Check for bare parameter packs in the return type and the
4929 exception specifiers. */
4930 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4931 /* Errors were already issued, set return type to int
4932 as the frontend doesn't expect error_mark_node as
4934 TREE_TYPE (type) = integer_type_node;
4935 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4936 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4938 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4939 && TYPE_DECL_ALIAS_P (decl))
4940 ? DECL_ORIGINAL_TYPE (decl)
4941 : TREE_TYPE (decl)))
4943 TREE_TYPE (decl) = error_mark_node;
4944 return error_mark_node;
4948 return process_partial_specialization (decl);
4950 args = current_template_args ();
4953 || TREE_CODE (ctx) == FUNCTION_DECL
4954 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4955 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4957 if (DECL_LANG_SPECIFIC (decl)
4958 && DECL_TEMPLATE_INFO (decl)
4959 && DECL_TI_TEMPLATE (decl))
4960 tmpl = DECL_TI_TEMPLATE (decl);
4961 /* If DECL is a TYPE_DECL for a class-template, then there won't
4962 be DECL_LANG_SPECIFIC. The information equivalent to
4963 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4964 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4965 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4966 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4968 /* Since a template declaration already existed for this
4969 class-type, we must be redeclaring it here. Make sure
4970 that the redeclaration is valid. */
4971 redeclare_class_template (TREE_TYPE (decl),
4972 current_template_parms);
4973 /* We don't need to create a new TEMPLATE_DECL; just use the
4974 one we already had. */
4975 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4979 tmpl = build_template_decl (decl, current_template_parms,
4983 if (DECL_LANG_SPECIFIC (decl)
4984 && DECL_TEMPLATE_SPECIALIZATION (decl))
4986 /* A specialization of a member template of a template
4988 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4989 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4990 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4996 tree a, t, current, parms;
4998 tree tinfo = get_template_info (decl);
5002 error ("template definition of non-template %q#D", decl);
5003 return error_mark_node;
5006 tmpl = TI_TEMPLATE (tinfo);
5008 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
5009 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
5010 && DECL_TEMPLATE_SPECIALIZATION (decl)
5011 && DECL_MEMBER_TEMPLATE_P (tmpl))
5015 /* The declaration is a specialization of a member
5016 template, declared outside the class. Therefore, the
5017 innermost template arguments will be NULL, so we
5018 replace them with the arguments determined by the
5019 earlier call to check_explicit_specialization. */
5020 args = DECL_TI_ARGS (decl);
5023 = build_template_decl (decl, current_template_parms,
5025 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
5026 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
5027 DECL_TI_TEMPLATE (decl) = new_tmpl;
5028 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
5029 DECL_TEMPLATE_INFO (new_tmpl)
5030 = build_template_info (tmpl, args);
5032 register_specialization (new_tmpl,
5033 most_general_template (tmpl),
5039 /* Make sure the template headers we got make sense. */
5041 parms = DECL_TEMPLATE_PARMS (tmpl);
5042 i = TMPL_PARMS_DEPTH (parms);
5043 if (TMPL_ARGS_DEPTH (args) != i)
5045 error ("expected %d levels of template parms for %q#D, got %d",
5046 i, decl, TMPL_ARGS_DEPTH (args));
5049 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5051 a = TMPL_ARGS_LEVEL (args, i);
5052 t = INNERMOST_TEMPLATE_PARMS (parms);
5054 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5056 if (current == decl)
5057 error ("got %d template parameters for %q#D",
5058 TREE_VEC_LENGTH (a), decl);
5060 error ("got %d template parameters for %q#T",
5061 TREE_VEC_LENGTH (a), current);
5062 error (" but %d required", TREE_VEC_LENGTH (t));
5063 return error_mark_node;
5066 if (current == decl)
5068 else if (current == NULL_TREE)
5069 /* Can happen in erroneous input. */
5072 current = (TYPE_P (current)
5073 ? TYPE_CONTEXT (current)
5074 : DECL_CONTEXT (current));
5077 /* Check that the parms are used in the appropriate qualifying scopes
5078 in the declarator. */
5079 if (!comp_template_args
5081 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5084 template arguments to %qD do not match original template %qD",
5085 decl, DECL_TEMPLATE_RESULT (tmpl));
5086 if (!uses_template_parms (TI_ARGS (tinfo)))
5087 inform (input_location, "use template<> for an explicit specialization");
5088 /* Avoid crash in import_export_decl. */
5089 DECL_INTERFACE_KNOWN (decl) = 1;
5090 return error_mark_node;
5094 DECL_TEMPLATE_RESULT (tmpl) = decl;
5095 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5097 /* Push template declarations for global functions and types. Note
5098 that we do not try to push a global template friend declared in a
5099 template class; such a thing may well depend on the template
5100 parameters of the class. */
5101 if (new_template_p && !ctx
5102 && !(is_friend && template_class_depth (current_class_type) > 0))
5104 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5105 if (tmpl == error_mark_node)
5106 return error_mark_node;
5108 /* Hide template friend classes that haven't been declared yet. */
5109 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5111 DECL_ANTICIPATED (tmpl) = 1;
5112 DECL_FRIEND_P (tmpl) = 1;
5118 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5121 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5122 if (DECL_CONV_FN_P (tmpl))
5124 int depth = TMPL_PARMS_DEPTH (parms);
5126 /* It is a conversion operator. See if the type converted to
5127 depends on innermost template operands. */
5129 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5131 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5134 /* Give template template parms a DECL_CONTEXT of the template
5135 for which they are a parameter. */
5136 parms = INNERMOST_TEMPLATE_PARMS (parms);
5137 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5139 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5140 if (TREE_CODE (parm) == TEMPLATE_DECL)
5141 DECL_CONTEXT (parm) = tmpl;
5145 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5146 back to its most general template. If TMPL is a specialization,
5147 ARGS may only have the innermost set of arguments. Add the missing
5148 argument levels if necessary. */
5149 if (DECL_TEMPLATE_INFO (tmpl))
5150 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5152 info = build_template_info (tmpl, args);
5154 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5155 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5158 if (primary && !DECL_LANG_SPECIFIC (decl))
5159 retrofit_lang_decl (decl);
5160 if (DECL_LANG_SPECIFIC (decl))
5161 DECL_TEMPLATE_INFO (decl) = info;
5164 return DECL_TEMPLATE_RESULT (tmpl);
5168 push_template_decl (tree decl)
5170 return push_template_decl_real (decl, false);
5173 /* Called when a class template TYPE is redeclared with the indicated
5174 template PARMS, e.g.:
5176 template <class T> struct S;
5177 template <class T> struct S {}; */
5180 redeclare_class_template (tree type, tree parms)
5186 if (!TYPE_TEMPLATE_INFO (type))
5188 error ("%qT is not a template type", type);
5192 tmpl = TYPE_TI_TEMPLATE (type);
5193 if (!PRIMARY_TEMPLATE_P (tmpl))
5194 /* The type is nested in some template class. Nothing to worry
5195 about here; there are no new template parameters for the nested
5201 error ("template specifiers not specified in declaration of %qD",
5206 parms = INNERMOST_TEMPLATE_PARMS (parms);
5207 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5209 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5211 error_n (input_location, TREE_VEC_LENGTH (parms),
5212 "redeclared with %d template parameter",
5213 "redeclared with %d template parameters",
5214 TREE_VEC_LENGTH (parms));
5215 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5216 "previous declaration %q+D used %d template parameter",
5217 "previous declaration %q+D used %d template parameters",
5218 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5222 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5229 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5230 || TREE_VEC_ELT (parms, i) == error_mark_node)
5233 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5234 if (tmpl_parm == error_mark_node)
5237 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5238 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5239 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5241 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5243 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5244 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5245 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5246 || (TREE_CODE (tmpl_parm) != PARM_DECL
5247 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5248 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5249 || (TREE_CODE (tmpl_parm) == PARM_DECL
5250 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5251 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5253 error ("template parameter %q+#D", tmpl_parm);
5254 error ("redeclared here as %q#D", parm);
5258 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5260 /* We have in [temp.param]:
5262 A template-parameter may not be given default arguments
5263 by two different declarations in the same scope. */
5264 error_at (input_location, "redefinition of default argument for %q#D", parm);
5265 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5266 "original definition appeared here");
5270 if (parm_default != NULL_TREE)
5271 /* Update the previous template parameters (which are the ones
5272 that will really count) with the new default value. */
5273 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5274 else if (tmpl_default != NULL_TREE)
5275 /* Update the new parameters, too; they'll be used as the
5276 parameters for any members. */
5277 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5283 /* Simplify EXPR if it is a non-dependent expression. Returns the
5284 (possibly simplified) expression. */
5287 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5289 if (expr == NULL_TREE)
5292 /* If we're in a template, but EXPR isn't value dependent, simplify
5293 it. We're supposed to treat:
5295 template <typename T> void f(T[1 + 1]);
5296 template <typename T> void f(T[2]);
5298 as two declarations of the same function, for example. */
5299 if (processing_template_decl
5300 && !type_dependent_expression_p (expr)
5301 && potential_constant_expression (expr)
5302 && !value_dependent_expression_p (expr))
5304 HOST_WIDE_INT saved_processing_template_decl;
5306 saved_processing_template_decl = processing_template_decl;
5307 processing_template_decl = 0;
5308 expr = tsubst_copy_and_build (expr,
5311 /*in_decl=*/NULL_TREE,
5312 /*function_p=*/false,
5313 /*integral_constant_expression_p=*/true);
5314 processing_template_decl = saved_processing_template_decl;
5320 fold_non_dependent_expr (tree expr)
5322 return fold_non_dependent_expr_sfinae (expr, tf_error);
5325 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5326 template declaration, or a TYPE_DECL for an alias declaration. */
5329 alias_type_or_template_p (tree t)
5333 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5336 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5337 || DECL_ALIAS_TEMPLATE_P (t));
5340 /* Return TRUE iff is a specialization of an alias template. */
5343 alias_template_specialization_p (tree t)
5347 return (primary_template_instantiation_p (t)
5348 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5351 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5352 must be a function or a pointer-to-function type, as specified
5353 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5354 and check that the resulting function has external linkage. */
5357 convert_nontype_argument_function (tree type, tree expr)
5361 linkage_kind linkage;
5363 fn = instantiate_type (type, fns, tf_none);
5364 if (fn == error_mark_node)
5365 return error_mark_node;
5368 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5369 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5370 if (BASELINK_P (fn_no_ptr))
5371 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5373 /* [temp.arg.nontype]/1
5375 A template-argument for a non-type, non-template template-parameter
5378 -- the address of an object or function with external [C++11: or
5379 internal] linkage. */
5380 linkage = decl_linkage (fn_no_ptr);
5381 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5383 if (cxx_dialect >= cxx0x)
5384 error ("%qE is not a valid template argument for type %qT "
5385 "because %qD has no linkage",
5386 expr, type, fn_no_ptr);
5388 error ("%qE is not a valid template argument for type %qT "
5389 "because %qD does not have external linkage",
5390 expr, type, fn_no_ptr);
5397 /* Subroutine of convert_nontype_argument.
5398 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5399 Emit an error otherwise. */
5402 check_valid_ptrmem_cst_expr (tree type, tree expr,
5403 tsubst_flags_t complain)
5406 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5408 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5410 if (complain & tf_error)
5412 error ("%qE is not a valid template argument for type %qT",
5414 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5419 /* Returns TRUE iff the address of OP is value-dependent.
5421 14.6.2.4 [temp.dep.temp]:
5422 A non-integral non-type template-argument is dependent if its type is
5423 dependent or it has either of the following forms
5426 and contains a nested-name-specifier which specifies a class-name that
5427 names a dependent type.
5429 We generalize this to just say that the address of a member of a
5430 dependent class is value-dependent; the above doesn't cover the
5431 address of a static data member named with an unqualified-id. */
5434 has_value_dependent_address (tree op)
5436 /* We could use get_inner_reference here, but there's no need;
5437 this is only relevant for template non-type arguments, which
5438 can only be expressed as &id-expression. */
5441 tree ctx = CP_DECL_CONTEXT (op);
5442 if (TYPE_P (ctx) && dependent_type_p (ctx))
5449 /* The next set of functions are used for providing helpful explanatory
5450 diagnostics for failed overload resolution. Their messages should be
5451 indented by two spaces for consistency with the messages in
5455 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5461 unify_parameter_deduction_failure (bool explain_p, tree parm)
5464 inform (input_location,
5465 " couldn't deduce template parameter %qD", parm);
5470 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5476 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5479 inform (input_location,
5480 " types %qT and %qT have incompatible cv-qualifiers",
5486 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5489 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5494 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5497 inform (input_location,
5498 " template parameter %qD is not a parameter pack, but "
5505 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5508 inform (input_location,
5509 " template argument %qE does not match "
5510 "pointer-to-member constant %qE",
5516 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5519 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5524 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5527 inform (input_location,
5528 " inconsistent parameter pack deduction with %qT and %qT",
5534 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5539 inform (input_location,
5540 " deduced conflicting types for parameter %qT (%qT and %qT)",
5541 parm, first, second);
5543 inform (input_location,
5544 " deduced conflicting values for non-type parameter "
5545 "%qE (%qE and %qE)", parm, first, second);
5551 unify_vla_arg (bool explain_p, tree arg)
5554 inform (input_location,
5555 " variable-sized array type %qT is not "
5556 "a valid template argument",
5562 unify_method_type_error (bool explain_p, tree arg)
5565 inform (input_location,
5566 " member function type %qT is not a valid template argument",
5572 unify_arity (bool explain_p, int have, int wanted)
5575 inform_n (input_location, wanted,
5576 " candidate expects %d argument, %d provided",
5577 " candidate expects %d arguments, %d provided",
5583 unify_too_many_arguments (bool explain_p, int have, int wanted)
5585 return unify_arity (explain_p, have, wanted);
5589 unify_too_few_arguments (bool explain_p, int have, int wanted)
5591 return unify_arity (explain_p, have, wanted);
5595 unify_arg_conversion (bool explain_p, tree to_type,
5596 tree from_type, tree arg)
5599 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5600 arg, from_type, to_type);
5605 unify_no_common_base (bool explain_p, enum template_base_result r,
5606 tree parm, tree arg)
5611 case tbr_ambiguous_baseclass:
5612 inform (input_location, " %qT is an ambiguous base class of %qT",
5616 inform (input_location, " %qT is not derived from %qT", arg, parm);
5623 unify_inconsistent_template_template_parameters (bool explain_p)
5626 inform (input_location,
5627 " template parameters of a template template argument are "
5628 "inconsistent with other deduced template arguments");
5633 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5636 inform (input_location,
5637 " can't deduce a template for %qT from non-template type %qT",
5643 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5646 inform (input_location,
5647 " template argument %qE does not match %qD", arg, parm);
5652 unify_overload_resolution_failure (bool explain_p, tree arg)
5655 inform (input_location,
5656 " could not resolve address from overloaded function %qE",
5661 /* Attempt to convert the non-type template parameter EXPR to the
5662 indicated TYPE. If the conversion is successful, return the
5663 converted value. If the conversion is unsuccessful, return
5664 NULL_TREE if we issued an error message, or error_mark_node if we
5665 did not. We issue error messages for out-and-out bad template
5666 parameters, but not simply because the conversion failed, since we
5667 might be just trying to do argument deduction. Both TYPE and EXPR
5668 must be non-dependent.
5670 The conversion follows the special rules described in
5671 [temp.arg.nontype], and it is much more strict than an implicit
5674 This function is called twice for each template argument (see
5675 lookup_template_class for a more accurate description of this
5676 problem). This means that we need to handle expressions which
5677 are not valid in a C++ source, but can be created from the
5678 first call (for instance, casts to perform conversions). These
5679 hacks can go away after we fix the double coercion problem. */
5682 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5686 /* Detect immediately string literals as invalid non-type argument.
5687 This special-case is not needed for correctness (we would easily
5688 catch this later), but only to provide better diagnostic for this
5689 common user mistake. As suggested by DR 100, we do not mention
5690 linkage issues in the diagnostic as this is not the point. */
5691 /* FIXME we're making this OK. */
5692 if (TREE_CODE (expr) == STRING_CST)
5694 if (complain & tf_error)
5695 error ("%qE is not a valid template argument for type %qT "
5696 "because string literals can never be used in this context",
5701 /* Add the ADDR_EXPR now for the benefit of
5702 value_dependent_expression_p. */
5703 if (TYPE_PTROBV_P (type)
5704 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5705 expr = decay_conversion (expr);
5707 /* If we are in a template, EXPR may be non-dependent, but still
5708 have a syntactic, rather than semantic, form. For example, EXPR
5709 might be a SCOPE_REF, rather than the VAR_DECL to which the
5710 SCOPE_REF refers. Preserving the qualifying scope is necessary
5711 so that access checking can be performed when the template is
5712 instantiated -- but here we need the resolved form so that we can
5713 convert the argument. */
5714 if (TYPE_REF_OBJ_P (type)
5715 && has_value_dependent_address (expr))
5716 /* If we want the address and it's value-dependent, don't fold. */;
5717 else if (!type_unknown_p (expr))
5718 expr = fold_non_dependent_expr_sfinae (expr, complain);
5719 if (error_operand_p (expr))
5720 return error_mark_node;
5721 expr_type = TREE_TYPE (expr);
5722 if (TREE_CODE (type) == REFERENCE_TYPE)
5723 expr = mark_lvalue_use (expr);
5725 expr = mark_rvalue_use (expr);
5727 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5728 to a non-type argument of "nullptr". */
5729 if (expr == nullptr_node
5730 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5731 expr = convert (type, expr);
5733 /* In C++11, integral or enumeration non-type template arguments can be
5734 arbitrary constant expressions. Pointer and pointer to
5735 member arguments can be general constant expressions that evaluate
5736 to a null value, but otherwise still need to be of a specific form. */
5737 if (cxx_dialect >= cxx0x)
5739 if (TREE_CODE (expr) == PTRMEM_CST)
5740 /* A PTRMEM_CST is already constant, and a valid template
5741 argument for a parameter of pointer to member type, we just want
5742 to leave it in that form rather than lower it to a
5744 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5745 expr = maybe_constant_value (expr);
5746 else if (TYPE_PTR_P (type)
5747 || TYPE_PTR_TO_MEMBER_P (type))
5749 tree folded = maybe_constant_value (expr);
5750 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5751 : null_member_pointer_value_p (folded))
5756 /* HACK: Due to double coercion, we can get a
5757 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5758 which is the tree that we built on the first call (see
5759 below when coercing to reference to object or to reference to
5760 function). We just strip everything and get to the arg.
5761 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5763 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5765 tree probe_type, probe = expr;
5766 if (REFERENCE_REF_P (probe))
5767 probe = TREE_OPERAND (probe, 0);
5768 probe_type = TREE_TYPE (probe);
5769 if (TREE_CODE (probe) == NOP_EXPR)
5771 /* ??? Maybe we could use convert_from_reference here, but we
5772 would need to relax its constraints because the NOP_EXPR
5773 could actually change the type to something more cv-qualified,
5774 and this is not folded by convert_from_reference. */
5775 tree addr = TREE_OPERAND (probe, 0);
5776 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5777 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5778 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5779 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5780 (TREE_TYPE (probe_type),
5781 TREE_TYPE (TREE_TYPE (addr))));
5783 expr = TREE_OPERAND (addr, 0);
5784 expr_type = TREE_TYPE (expr);
5788 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5789 parameter is a pointer to object, through decay and
5790 qualification conversion. Let's strip everything. */
5791 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5794 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5795 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5796 /* Skip the ADDR_EXPR only if it is part of the decay for
5797 an array. Otherwise, it is part of the original argument
5798 in the source code. */
5799 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5800 expr = TREE_OPERAND (expr, 0);
5801 expr_type = TREE_TYPE (expr);
5804 /* [temp.arg.nontype]/5, bullet 1
5806 For a non-type template-parameter of integral or enumeration type,
5807 integral promotions (_conv.prom_) and integral conversions
5808 (_conv.integral_) are applied. */
5809 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5811 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5812 t = maybe_constant_value (t);
5813 if (t != error_mark_node)
5816 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5817 return error_mark_node;
5819 /* Notice that there are constant expressions like '4 % 0' which
5820 do not fold into integer constants. */
5821 if (TREE_CODE (expr) != INTEGER_CST)
5823 if (complain & tf_error)
5825 int errs = errorcount, warns = warningcount;
5826 if (processing_template_decl
5827 && !require_potential_constant_expression (expr))
5829 expr = cxx_constant_value (expr);
5830 if (errorcount > errs || warningcount > warns)
5831 inform (EXPR_LOC_OR_HERE (expr),
5832 "in template argument for type %qT ", type);
5833 if (expr == error_mark_node)
5835 /* else cxx_constant_value complained but gave us
5836 a real constant, so go ahead. */
5837 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5843 /* [temp.arg.nontype]/5, bullet 2
5845 For a non-type template-parameter of type pointer to object,
5846 qualification conversions (_conv.qual_) and the array-to-pointer
5847 conversion (_conv.array_) are applied. */
5848 else if (TYPE_PTROBV_P (type))
5850 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5852 A template-argument for a non-type, non-template template-parameter
5853 shall be one of: [...]
5855 -- the name of a non-type template-parameter;
5856 -- the address of an object or function with external linkage, [...]
5857 expressed as "& id-expression" where the & is optional if the name
5858 refers to a function or array, or if the corresponding
5859 template-parameter is a reference.
5861 Here, we do not care about functions, as they are invalid anyway
5862 for a parameter of type pointer-to-object. */
5864 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5865 /* Non-type template parameters are OK. */
5867 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5868 /* Null pointer values are OK in C++11. */;
5869 else if (TREE_CODE (expr) != ADDR_EXPR
5870 && TREE_CODE (expr_type) != ARRAY_TYPE)
5872 if (TREE_CODE (expr) == VAR_DECL)
5874 error ("%qD is not a valid template argument "
5875 "because %qD is a variable, not the address of "
5880 /* Other values, like integer constants, might be valid
5881 non-type arguments of some other type. */
5882 return error_mark_node;
5888 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5889 ? TREE_OPERAND (expr, 0) : expr);
5890 if (TREE_CODE (decl) != VAR_DECL)
5892 error ("%qE is not a valid template argument of type %qT "
5893 "because %qE is not a variable",
5897 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5899 error ("%qE is not a valid template argument of type %qT "
5900 "because %qD does not have external linkage",
5904 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5906 error ("%qE is not a valid template argument of type %qT "
5907 "because %qD has no linkage",
5913 expr = decay_conversion (expr);
5914 if (expr == error_mark_node)
5915 return error_mark_node;
5917 expr = perform_qualification_conversions (type, expr);
5918 if (expr == error_mark_node)
5919 return error_mark_node;
5921 /* [temp.arg.nontype]/5, bullet 3
5923 For a non-type template-parameter of type reference to object, no
5924 conversions apply. The type referred to by the reference may be more
5925 cv-qualified than the (otherwise identical) type of the
5926 template-argument. The template-parameter is bound directly to the
5927 template-argument, which must be an lvalue. */
5928 else if (TYPE_REF_OBJ_P (type))
5930 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5932 return error_mark_node;
5934 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5936 error ("%qE is not a valid template argument for type %qT "
5937 "because of conflicts in cv-qualification", expr, type);
5941 if (!real_lvalue_p (expr))
5943 error ("%qE is not a valid template argument for type %qT "
5944 "because it is not an lvalue", expr, type);
5948 /* [temp.arg.nontype]/1
5950 A template-argument for a non-type, non-template template-parameter
5951 shall be one of: [...]
5953 -- the address of an object or function with external linkage. */
5954 if (TREE_CODE (expr) == INDIRECT_REF
5955 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5957 expr = TREE_OPERAND (expr, 0);
5960 error ("%q#D is not a valid template argument for type %qT "
5961 "because a reference variable does not have a constant "
5962 "address", expr, type);
5969 error ("%qE is not a valid template argument for type %qT "
5970 "because it is not an object with external linkage",
5975 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5977 error ("%qE is not a valid template argument for type %qT "
5978 "because object %qD has not external linkage",
5983 expr = build_nop (type, build_address (expr));
5985 /* [temp.arg.nontype]/5, bullet 4
5987 For a non-type template-parameter of type pointer to function, only
5988 the function-to-pointer conversion (_conv.func_) is applied. If the
5989 template-argument represents a set of overloaded functions (or a
5990 pointer to such), the matching function is selected from the set
5992 else if (TYPE_PTRFN_P (type))
5994 /* If the argument is a template-id, we might not have enough
5995 context information to decay the pointer. */
5996 if (!type_unknown_p (expr_type))
5998 expr = decay_conversion (expr);
5999 if (expr == error_mark_node)
6000 return error_mark_node;
6003 if (cxx_dialect >= cxx0x && integer_zerop (expr))
6004 /* Null pointer values are OK in C++11. */
6005 return perform_qualification_conversions (type, expr);
6007 expr = convert_nontype_argument_function (type, expr);
6008 if (!expr || expr == error_mark_node)
6011 if (TREE_CODE (expr) != ADDR_EXPR)
6013 error ("%qE is not a valid template argument for type %qT", expr, type);
6014 error ("it must be the address of a function with external linkage");
6018 /* [temp.arg.nontype]/5, bullet 5
6020 For a non-type template-parameter of type reference to function, no
6021 conversions apply. If the template-argument represents a set of
6022 overloaded functions, the matching function is selected from the set
6024 else if (TYPE_REFFN_P (type))
6026 if (TREE_CODE (expr) == ADDR_EXPR)
6028 error ("%qE is not a valid template argument for type %qT "
6029 "because it is a pointer", expr, type);
6030 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
6034 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
6035 if (!expr || expr == error_mark_node)
6038 expr = build_nop (type, build_address (expr));
6040 /* [temp.arg.nontype]/5, bullet 6
6042 For a non-type template-parameter of type pointer to member function,
6043 no conversions apply. If the template-argument represents a set of
6044 overloaded member functions, the matching member function is selected
6045 from the set (_over.over_). */
6046 else if (TYPE_PTRMEMFUNC_P (type))
6048 expr = instantiate_type (type, expr, tf_none);
6049 if (expr == error_mark_node)
6050 return error_mark_node;
6052 /* [temp.arg.nontype] bullet 1 says the pointer to member
6053 expression must be a pointer-to-member constant. */
6054 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6055 return error_mark_node;
6057 /* There is no way to disable standard conversions in
6058 resolve_address_of_overloaded_function (called by
6059 instantiate_type). It is possible that the call succeeded by
6060 converting &B::I to &D::I (where B is a base of D), so we need
6061 to reject this conversion here.
6063 Actually, even if there was a way to disable standard conversions,
6064 it would still be better to reject them here so that we can
6065 provide a superior diagnostic. */
6066 if (!same_type_p (TREE_TYPE (expr), type))
6068 error ("%qE is not a valid template argument for type %qT "
6069 "because it is of type %qT", expr, type,
6071 /* If we are just one standard conversion off, explain. */
6072 if (can_convert (type, TREE_TYPE (expr)))
6073 inform (input_location,
6074 "standard conversions are not allowed in this context");
6078 /* [temp.arg.nontype]/5, bullet 7
6080 For a non-type template-parameter of type pointer to data member,
6081 qualification conversions (_conv.qual_) are applied. */
6082 else if (TYPE_PTRMEM_P (type))
6084 /* [temp.arg.nontype] bullet 1 says the pointer to member
6085 expression must be a pointer-to-member constant. */
6086 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6087 return error_mark_node;
6089 expr = perform_qualification_conversions (type, expr);
6090 if (expr == error_mark_node)
6093 else if (NULLPTR_TYPE_P (type))
6095 if (expr != nullptr_node)
6097 error ("%qE is not a valid template argument for type %qT "
6098 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6103 /* A template non-type parameter must be one of the above. */
6107 /* Sanity check: did we actually convert the argument to the
6109 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6110 (type, TREE_TYPE (expr)));
6114 /* Subroutine of coerce_template_template_parms, which returns 1 if
6115 PARM_PARM and ARG_PARM match using the rule for the template
6116 parameters of template template parameters. Both PARM and ARG are
6117 template parameters; the rest of the arguments are the same as for
6118 coerce_template_template_parms.
6121 coerce_template_template_parm (tree parm,
6123 tsubst_flags_t complain,
6127 if (arg == NULL_TREE || arg == error_mark_node
6128 || parm == NULL_TREE || parm == error_mark_node)
6131 if (TREE_CODE (arg) != TREE_CODE (parm))
6134 switch (TREE_CODE (parm))
6137 /* We encounter instantiations of templates like
6138 template <template <template <class> class> class TT>
6141 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6142 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6144 if (!coerce_template_template_parms
6145 (parmparm, argparm, complain, in_decl, outer_args))
6151 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6152 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6153 /* Argument is a parameter pack but parameter is not. */
6158 /* The tsubst call is used to handle cases such as
6160 template <int> class C {};
6161 template <class T, template <T> class TT> class D {};
6164 i.e. the parameter list of TT depends on earlier parameters. */
6165 if (!uses_template_parms (TREE_TYPE (arg))
6167 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6171 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6172 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6173 /* Argument is a parameter pack but parameter is not. */
6186 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6187 template template parameters. Both PARM_PARMS and ARG_PARMS are
6188 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6191 Consider the example:
6192 template <class T> class A;
6193 template<template <class U> class TT> class B;
6195 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6196 the parameters to A, and OUTER_ARGS contains A. */
6199 coerce_template_template_parms (tree parm_parms,
6201 tsubst_flags_t complain,
6205 int nparms, nargs, i;
6209 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6210 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6212 nparms = TREE_VEC_LENGTH (parm_parms);
6213 nargs = TREE_VEC_LENGTH (arg_parms);
6215 /* Determine whether we have a parameter pack at the end of the
6216 template template parameter's template parameter list. */
6217 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6219 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6221 if (parm == error_mark_node)
6224 switch (TREE_CODE (parm))
6228 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6233 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6243 && !(variadic_p && nargs >= nparms - 1))
6246 /* Check all of the template parameters except the parameter pack at
6247 the end (if any). */
6248 for (i = 0; i < nparms - variadic_p; ++i)
6250 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6251 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6254 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6255 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6257 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6265 /* Check each of the template parameters in the template
6266 argument against the template parameter pack at the end of
6267 the template template parameter. */
6268 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6271 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6273 for (; i < nargs; ++i)
6275 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6278 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6280 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6289 /* Verifies that the deduced template arguments (in TARGS) for the
6290 template template parameters (in TPARMS) represent valid bindings,
6291 by comparing the template parameter list of each template argument
6292 to the template parameter list of its corresponding template
6293 template parameter, in accordance with DR150. This
6294 routine can only be called after all template arguments have been
6295 deduced. It will return TRUE if all of the template template
6296 parameter bindings are okay, FALSE otherwise. */
6298 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6300 int i, ntparms = TREE_VEC_LENGTH (tparms);
6303 /* We're dealing with template parms in this process. */
6304 ++processing_template_decl;
6306 targs = INNERMOST_TEMPLATE_ARGS (targs);
6308 for (i = 0; i < ntparms; ++i)
6310 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6311 tree targ = TREE_VEC_ELT (targs, i);
6313 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6315 tree packed_args = NULL_TREE;
6318 if (ARGUMENT_PACK_P (targ))
6320 /* Look inside the argument pack. */
6321 packed_args = ARGUMENT_PACK_ARGS (targ);
6322 len = TREE_VEC_LENGTH (packed_args);
6325 for (idx = 0; idx < len; ++idx)
6327 tree targ_parms = NULL_TREE;
6330 /* Extract the next argument from the argument
6332 targ = TREE_VEC_ELT (packed_args, idx);
6334 if (PACK_EXPANSION_P (targ))
6335 /* Look at the pattern of the pack expansion. */
6336 targ = PACK_EXPANSION_PATTERN (targ);
6338 /* Extract the template parameters from the template
6340 if (TREE_CODE (targ) == TEMPLATE_DECL)
6341 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6342 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6343 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6345 /* Verify that we can coerce the template template
6346 parameters from the template argument to the template
6347 parameter. This requires an exact match. */
6349 && !coerce_template_template_parms
6350 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6365 --processing_template_decl;
6369 /* Since type attributes aren't mangled, we need to strip them from
6370 template type arguments. */
6373 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6376 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6378 mv = TYPE_MAIN_VARIANT (arg);
6379 arg = strip_typedefs (arg);
6380 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6381 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6383 if (complain & tf_warning)
6384 warning (0, "ignoring attributes on template argument %qT", arg);
6385 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6386 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6391 /* Convert the indicated template ARG as necessary to match the
6392 indicated template PARM. Returns the converted ARG, or
6393 error_mark_node if the conversion was unsuccessful. Error and
6394 warning messages are issued under control of COMPLAIN. This
6395 conversion is for the Ith parameter in the parameter list. ARGS is
6396 the full set of template arguments deduced so far. */
6399 convert_template_argument (tree parm,
6402 tsubst_flags_t complain,
6408 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6410 if (TREE_CODE (arg) == TREE_LIST
6411 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6413 /* The template argument was the name of some
6414 member function. That's usually
6415 invalid, but static members are OK. In any
6416 case, grab the underlying fields/functions
6417 and issue an error later if required. */
6418 orig_arg = TREE_VALUE (arg);
6419 TREE_TYPE (arg) = unknown_type_node;
6424 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6425 requires_type = (TREE_CODE (parm) == TYPE_DECL
6426 || requires_tmpl_type);
6428 /* When determining whether an argument pack expansion is a template,
6429 look at the pattern. */
6430 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6431 arg = PACK_EXPANSION_PATTERN (arg);
6433 /* Deal with an injected-class-name used as a template template arg. */
6434 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6436 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6437 if (TREE_CODE (t) == TEMPLATE_DECL)
6439 if (cxx_dialect >= cxx0x)
6440 /* OK under DR 1004. */;
6441 else if (complain & tf_warning_or_error)
6442 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6443 " used as template template argument", TYPE_NAME (arg));
6444 else if (flag_pedantic_errors)
6452 ((TREE_CODE (arg) == TEMPLATE_DECL
6453 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6454 || (requires_tmpl_type && TREE_CODE (arg) == TYPE_ARGUMENT_PACK)
6455 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6456 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6459 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6460 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6461 arg = TYPE_STUB_DECL (arg);
6463 is_type = TYPE_P (arg) || is_tmpl_type;
6465 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6466 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6468 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR)
6470 if (complain & tf_error)
6471 error ("invalid use of destructor %qE as a type", orig_arg);
6472 return error_mark_node;
6475 permerror (input_location,
6476 "to refer to a type member of a template parameter, "
6477 "use %<typename %E%>", orig_arg);
6479 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6480 TREE_OPERAND (arg, 1),
6482 complain & tf_error);
6486 if (is_type != requires_type)
6490 if (complain & tf_error)
6492 error ("type/value mismatch at argument %d in template "
6493 "parameter list for %qD",
6496 error (" expected a constant of type %qT, got %qT",
6498 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6499 else if (requires_tmpl_type)
6500 error (" expected a class template, got %qE", orig_arg);
6502 error (" expected a type, got %qE", orig_arg);
6505 return error_mark_node;
6507 if (is_tmpl_type ^ requires_tmpl_type)
6509 if (in_decl && (complain & tf_error))
6511 error ("type/value mismatch at argument %d in template "
6512 "parameter list for %qD",
6515 error (" expected a type, got %qT", DECL_NAME (arg));
6517 error (" expected a class template, got %qT", orig_arg);
6519 return error_mark_node;
6524 if (requires_tmpl_type)
6526 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6528 else if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6529 /* The number of argument required is not known yet.
6530 Just accept it for now. */
6531 val = TREE_TYPE (arg);
6534 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6537 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6539 if (coerce_template_template_parms (parmparm, argparm,
6545 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6547 if (val != error_mark_node)
6549 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6550 val = TREE_TYPE (val);
6551 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6552 val = make_pack_expansion (val);
6557 if (in_decl && (complain & tf_error))
6559 error ("type/value mismatch at argument %d in "
6560 "template parameter list for %qD",
6562 error (" expected a template of type %qD, got %qT",
6566 val = error_mark_node;
6572 /* We only form one instance of each template specialization.
6573 Therefore, if we use a non-canonical variant (i.e., a
6574 typedef), any future messages referring to the type will use
6575 the typedef, which is confusing if those future uses do not
6576 themselves also use the typedef. */
6578 val = canonicalize_type_argument (val, complain);
6582 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6584 if (invalid_nontype_parm_type_p (t, complain))
6585 return error_mark_node;
6587 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6589 if (same_type_p (t, TREE_TYPE (orig_arg)))
6593 /* Not sure if this is reachable, but it doesn't hurt
6595 error ("type mismatch in nontype parameter pack");
6596 val = error_mark_node;
6599 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6600 /* We used to call digest_init here. However, digest_init
6601 will report errors, which we don't want when complain
6602 is zero. More importantly, digest_init will try too
6603 hard to convert things: for example, `0' should not be
6604 converted to pointer type at this point according to
6605 the standard. Accepting this is not merely an
6606 extension, since deciding whether or not these
6607 conversions can occur is part of determining which
6608 function template to call, or whether a given explicit
6609 argument specification is valid. */
6610 val = convert_nontype_argument (t, orig_arg, complain);
6614 if (val == NULL_TREE)
6615 val = error_mark_node;
6616 else if (val == error_mark_node && (complain & tf_error))
6617 error ("could not convert template argument %qE to %qT", orig_arg, t);
6619 if (TREE_CODE (val) == SCOPE_REF)
6621 /* Strip typedefs from the SCOPE_REF. */
6622 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6623 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6625 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6626 QUALIFIED_NAME_IS_TEMPLATE (val));
6633 /* Coerces the remaining template arguments in INNER_ARGS (from
6634 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6635 Returns the coerced argument pack. PARM_IDX is the position of this
6636 parameter in the template parameter list. ARGS is the original
6637 template argument list. */
6639 coerce_template_parameter_pack (tree parms,
6647 tsubst_flags_t complain)
6649 tree parm = TREE_VEC_ELT (parms, parm_idx);
6650 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6653 tree packed_types = NULL_TREE;
6655 if (arg_idx > nargs)
6658 packed_args = make_tree_vec (nargs - arg_idx);
6660 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6661 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6663 /* When the template parameter is a non-type template
6664 parameter pack whose type uses parameter packs, we need
6665 to look at each of the template arguments
6666 separately. Build a vector of the types for these
6667 non-type template parameters in PACKED_TYPES. */
6669 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6670 packed_types = tsubst_pack_expansion (expansion, args,
6673 if (packed_types == error_mark_node)
6674 return error_mark_node;
6676 /* Check that we have the right number of arguments. */
6678 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6679 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6682 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6683 error ("wrong number of template arguments (%d, should be %d)",
6684 nargs, needed_parms);
6685 return error_mark_node;
6688 /* If we aren't able to check the actual arguments now
6689 (because they haven't been expanded yet), we can at least
6690 verify that all of the types used for the non-type
6691 template parameter pack are, in fact, valid for non-type
6692 template parameters. */
6694 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6696 int j, len = TREE_VEC_LENGTH (packed_types);
6697 for (j = 0; j < len; ++j)
6699 tree t = TREE_VEC_ELT (packed_types, j);
6700 if (invalid_nontype_parm_type_p (t, complain))
6701 return error_mark_node;
6706 /* Convert the remaining arguments, which will be a part of the
6707 parameter pack "parm". */
6708 for (; arg_idx < nargs; ++arg_idx)
6710 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6711 tree actual_parm = TREE_VALUE (parm);
6713 if (packed_types && !PACK_EXPANSION_P (arg))
6715 /* When we have a vector of types (corresponding to the
6716 non-type template parameter pack that uses parameter
6717 packs in its type, as mention above), and the
6718 argument is not an expansion (which expands to a
6719 currently unknown number of arguments), clone the
6720 parm and give it the next type in PACKED_TYPES. */
6721 actual_parm = copy_node (actual_parm);
6722 TREE_TYPE (actual_parm) =
6723 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6726 if (arg != error_mark_node)
6727 arg = convert_template_argument (actual_parm,
6728 arg, new_args, complain, parm_idx,
6730 if (arg == error_mark_node)
6732 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6735 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6736 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6737 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6740 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6741 TREE_TYPE (argument_pack)
6742 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6743 TREE_CONSTANT (argument_pack) = 1;
6746 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6747 #ifdef ENABLE_CHECKING
6748 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6749 TREE_VEC_LENGTH (packed_args));
6751 return argument_pack;
6754 /* Returns true if the template argument vector ARGS contains
6755 any pack expansions, false otherwise. */
6758 any_pack_expanson_args_p (tree args)
6762 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
6763 if (PACK_EXPANSION_P (TREE_VEC_ELT (args, i)))
6768 /* Convert all template arguments to their appropriate types, and
6769 return a vector containing the innermost resulting template
6770 arguments. If any error occurs, return error_mark_node. Error and
6771 warning messages are issued under control of COMPLAIN.
6773 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6774 for arguments not specified in ARGS. Otherwise, if
6775 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6776 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6777 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6781 coerce_template_parms (tree parms,
6784 tsubst_flags_t complain,
6785 bool require_all_args,
6786 bool use_default_args)
6788 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6791 tree new_inner_args;
6792 int saved_unevaluated_operand;
6793 int saved_inhibit_evaluation_warnings;
6795 /* When used as a boolean value, indicates whether this is a
6796 variadic template parameter list. Since it's an int, we can also
6797 subtract it from nparms to get the number of non-variadic
6800 int post_variadic_parms = 0;
6802 if (args == error_mark_node)
6803 return error_mark_node;
6805 nparms = TREE_VEC_LENGTH (parms);
6807 /* Determine if there are any parameter packs. */
6808 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6810 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6812 ++post_variadic_parms;
6813 if (template_parameter_pack_p (tparm))
6817 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6818 /* If there are no parameters that follow a parameter pack, we need to
6819 expand any argument packs so that we can deduce a parameter pack from
6820 some non-packed args followed by an argument pack, as in variadic85.C.
6821 If there are such parameters, we need to leave argument packs intact
6822 so the arguments are assigned properly. This can happen when dealing
6823 with a nested class inside a partial specialization of a class
6824 template, as in variadic92.C, or when deducing a template parameter pack
6825 from a sub-declarator, as in variadic114.C. */
6826 if (!post_variadic_parms)
6827 inner_args = expand_template_argument_pack (inner_args);
6829 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6830 if ((nargs > nparms && !variadic_p)
6831 || (nargs < nparms - variadic_p
6833 && !any_pack_expanson_args_p (inner_args)
6834 && (!use_default_args
6835 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6836 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6838 if (complain & tf_error)
6842 nparms -= variadic_p;
6843 error ("wrong number of template arguments "
6844 "(%d, should be %d or more)", nargs, nparms);
6847 error ("wrong number of template arguments "
6848 "(%d, should be %d)", nargs, nparms);
6851 error ("provided for %q+D", in_decl);
6854 return error_mark_node;
6857 /* We need to evaluate the template arguments, even though this
6858 template-id may be nested within a "sizeof". */
6859 saved_unevaluated_operand = cp_unevaluated_operand;
6860 cp_unevaluated_operand = 0;
6861 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6862 c_inhibit_evaluation_warnings = 0;
6863 new_inner_args = make_tree_vec (nparms);
6864 new_args = add_outermost_template_args (args, new_inner_args);
6865 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6870 /* Get the Ith template parameter. */
6871 parm = TREE_VEC_ELT (parms, parm_idx);
6873 if (parm == error_mark_node)
6875 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6879 /* Calculate the next argument. */
6880 if (arg_idx < nargs)
6881 arg = TREE_VEC_ELT (inner_args, arg_idx);
6885 if (template_parameter_pack_p (TREE_VALUE (parm))
6886 && !(arg && ARGUMENT_PACK_P (arg)))
6888 /* All remaining arguments will be placed in the
6889 template parameter pack PARM. */
6890 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6891 inner_args, arg_idx,
6895 /* Store this argument. */
6896 if (arg == error_mark_node)
6898 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6900 /* We are done with all of the arguments. */
6907 if (PACK_EXPANSION_P (arg))
6909 /* We don't know how many args we have yet, just
6910 use the unconverted ones for now. */
6911 new_inner_args = inner_args;
6915 else if (require_all_args)
6917 /* There must be a default arg in this case. */
6918 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6920 /* The position of the first default template argument,
6921 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6923 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6924 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6929 if (arg == error_mark_node)
6931 if (complain & tf_error)
6932 error ("template argument %d is invalid", arg_idx + 1);
6935 /* This only occurs if there was an error in the template
6936 parameter list itself (which we would already have
6937 reported) that we are trying to recover from, e.g., a class
6938 template with a parameter list such as
6939 template<typename..., typename>. */
6942 arg = convert_template_argument (TREE_VALUE (parm),
6943 arg, new_args, complain,
6946 if (arg == error_mark_node)
6948 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6950 cp_unevaluated_operand = saved_unevaluated_operand;
6951 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6954 return error_mark_node;
6956 #ifdef ENABLE_CHECKING
6957 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6958 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6959 TREE_VEC_LENGTH (new_inner_args));
6962 return new_inner_args;
6965 /* Returns 1 if template args OT and NT are equivalent. */
6968 template_args_equal (tree ot, tree nt)
6972 if (nt == NULL_TREE || ot == NULL_TREE)
6975 if (TREE_CODE (nt) == TREE_VEC)
6976 /* For member templates */
6977 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6978 else if (PACK_EXPANSION_P (ot))
6979 return (PACK_EXPANSION_P (nt)
6980 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6981 PACK_EXPANSION_PATTERN (nt))
6982 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6983 PACK_EXPANSION_EXTRA_ARGS (nt)));
6984 else if (ARGUMENT_PACK_P (ot))
6989 if (!ARGUMENT_PACK_P (nt))
6992 opack = ARGUMENT_PACK_ARGS (ot);
6993 npack = ARGUMENT_PACK_ARGS (nt);
6994 len = TREE_VEC_LENGTH (opack);
6995 if (TREE_VEC_LENGTH (npack) != len)
6997 for (i = 0; i < len; ++i)
6998 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6999 TREE_VEC_ELT (npack, i)))
7003 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
7005 /* We get here probably because we are in the middle of substituting
7006 into the pattern of a pack expansion. In that case the
7007 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
7008 interested in. So we want to use the initial pack argument for
7010 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
7011 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
7012 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
7013 return template_args_equal (ot, nt);
7015 else if (TYPE_P (nt))
7016 return TYPE_P (ot) && same_type_p (ot, nt);
7017 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
7020 return cp_tree_equal (ot, nt);
7023 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
7024 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
7025 NEWARG_PTR with the offending arguments if they are non-NULL. */
7028 comp_template_args_with_info (tree oldargs, tree newargs,
7029 tree *oldarg_ptr, tree *newarg_ptr)
7033 if (oldargs == newargs)
7036 if (!oldargs || !newargs)
7039 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
7042 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
7044 tree nt = TREE_VEC_ELT (newargs, i);
7045 tree ot = TREE_VEC_ELT (oldargs, i);
7047 if (! template_args_equal (ot, nt))
7049 if (oldarg_ptr != NULL)
7051 if (newarg_ptr != NULL)
7059 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
7060 of template arguments. Returns 0 otherwise. */
7063 comp_template_args (tree oldargs, tree newargs)
7065 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
7069 add_pending_template (tree d)
7071 tree ti = (TYPE_P (d)
7072 ? CLASSTYPE_TEMPLATE_INFO (d)
7073 : DECL_TEMPLATE_INFO (d));
7074 struct pending_template *pt;
7077 if (TI_PENDING_TEMPLATE_FLAG (ti))
7080 /* We are called both from instantiate_decl, where we've already had a
7081 tinst_level pushed, and instantiate_template, where we haven't.
7083 level = !current_tinst_level || current_tinst_level->decl != d;
7086 push_tinst_level (d);
7088 pt = ggc_alloc_pending_template ();
7090 pt->tinst = current_tinst_level;
7091 if (last_pending_template)
7092 last_pending_template->next = pt;
7094 pending_templates = pt;
7096 last_pending_template = pt;
7098 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7105 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7106 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7107 documentation for TEMPLATE_ID_EXPR. */
7110 lookup_template_function (tree fns, tree arglist)
7114 if (fns == error_mark_node || arglist == error_mark_node)
7115 return error_mark_node;
7117 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7119 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7121 error ("%q#D is not a function template", fns);
7122 return error_mark_node;
7125 if (BASELINK_P (fns))
7127 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7129 BASELINK_FUNCTIONS (fns),
7134 type = TREE_TYPE (fns);
7135 if (TREE_CODE (fns) == OVERLOAD || !type)
7136 type = unknown_type_node;
7138 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7141 /* Within the scope of a template class S<T>, the name S gets bound
7142 (in build_self_reference) to a TYPE_DECL for the class, not a
7143 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7144 or one of its enclosing classes, and that type is a template,
7145 return the associated TEMPLATE_DECL. Otherwise, the original
7148 Also handle the case when DECL is a TREE_LIST of ambiguous
7149 injected-class-names from different bases. */
7152 maybe_get_template_decl_from_type_decl (tree decl)
7154 if (decl == NULL_TREE)
7157 /* DR 176: A lookup that finds an injected-class-name (10.2
7158 [class.member.lookup]) can result in an ambiguity in certain cases
7159 (for example, if it is found in more than one base class). If all of
7160 the injected-class-names that are found refer to specializations of
7161 the same class template, and if the name is followed by a
7162 template-argument-list, the reference refers to the class template
7163 itself and not a specialization thereof, and is not ambiguous. */
7164 if (TREE_CODE (decl) == TREE_LIST)
7166 tree t, tmpl = NULL_TREE;
7167 for (t = decl; t; t = TREE_CHAIN (t))
7169 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7172 else if (tmpl != elt)
7175 if (tmpl && t == NULL_TREE)
7181 return (decl != NULL_TREE
7182 && DECL_SELF_REFERENCE_P (decl)
7183 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7184 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7187 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7188 parameters, find the desired type.
7190 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7192 IN_DECL, if non-NULL, is the template declaration we are trying to
7195 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7196 the class we are looking up.
7198 Issue error and warning messages under control of COMPLAIN.
7200 If the template class is really a local class in a template
7201 function, then the FUNCTION_CONTEXT is the function in which it is
7204 ??? Note that this function is currently called *twice* for each
7205 template-id: the first time from the parser, while creating the
7206 incomplete type (finish_template_type), and the second type during the
7207 real instantiation (instantiate_template_class). This is surely something
7208 that we want to avoid. It also causes some problems with argument
7209 coercion (see convert_nontype_argument for more information on this). */
7212 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7213 int entering_scope, tsubst_flags_t complain)
7215 tree templ = NULL_TREE, parmlist;
7222 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7224 tree value = innermost_non_namespace_value (d1);
7225 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7230 push_decl_namespace (context);
7231 templ = lookup_name (d1);
7232 templ = maybe_get_template_decl_from_type_decl (templ);
7234 pop_decl_namespace ();
7237 context = DECL_CONTEXT (templ);
7239 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7241 tree type = TREE_TYPE (d1);
7243 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7244 an implicit typename for the second A. Deal with it. */
7245 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7246 type = TREE_TYPE (type);
7248 if (CLASSTYPE_TEMPLATE_INFO (type))
7250 templ = CLASSTYPE_TI_TEMPLATE (type);
7251 d1 = DECL_NAME (templ);
7254 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7255 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7257 templ = TYPE_TI_TEMPLATE (d1);
7258 d1 = DECL_NAME (templ);
7260 else if (TREE_CODE (d1) == TEMPLATE_DECL
7261 && DECL_TEMPLATE_RESULT (d1)
7262 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7265 d1 = DECL_NAME (templ);
7266 context = DECL_CONTEXT (templ);
7269 /* Issue an error message if we didn't find a template. */
7272 if (complain & tf_error)
7273 error ("%qT is not a template", d1);
7274 return error_mark_node;
7277 if (TREE_CODE (templ) != TEMPLATE_DECL
7278 /* Make sure it's a user visible template, if it was named by
7280 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7281 && !PRIMARY_TEMPLATE_P (templ)))
7283 if (complain & tf_error)
7285 error ("non-template type %qT used as a template", d1);
7287 error ("for template declaration %q+D", in_decl);
7289 return error_mark_node;
7292 complain &= ~tf_user;
7294 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7296 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7297 template arguments */
7303 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7305 /* Consider an example where a template template parameter declared as
7307 template <class T, class U = std::allocator<T> > class TT
7309 The template parameter level of T and U are one level larger than
7310 of TT. To proper process the default argument of U, say when an
7311 instantiation `TT<int>' is seen, we need to build the full
7312 arguments containing {int} as the innermost level. Outer levels,
7313 available when not appearing as default template argument, can be
7314 obtained from the arguments of the enclosing template.
7316 Suppose that TT is later substituted with std::vector. The above
7317 instantiation is `TT<int, std::allocator<T> >' with TT at
7318 level 1, and T at level 2, while the template arguments at level 1
7319 becomes {std::vector} and the inner level 2 is {int}. */
7321 outer = DECL_CONTEXT (templ);
7323 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7324 else if (current_template_parms)
7325 /* This is an argument of the current template, so we haven't set
7326 DECL_CONTEXT yet. */
7327 outer = current_template_args ();
7330 arglist = add_to_template_args (outer, arglist);
7332 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7334 /*require_all_args=*/true,
7335 /*use_default_args=*/true);
7336 if (arglist2 == error_mark_node
7337 || (!uses_template_parms (arglist2)
7338 && check_instantiated_args (templ, arglist2, complain)))
7339 return error_mark_node;
7341 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7346 tree template_type = TREE_TYPE (templ);
7349 tree found = NULL_TREE;
7352 int is_dependent_type;
7353 int use_partial_inst_tmpl = false;
7355 if (template_type == error_mark_node)
7356 /* An error occured while building the template TEMPL, and a
7357 diagnostic has most certainly been emitted for that
7358 already. Let's propagate that error. */
7359 return error_mark_node;
7361 gen_tmpl = most_general_template (templ);
7362 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7363 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7364 arg_depth = TMPL_ARGS_DEPTH (arglist);
7366 if (arg_depth == 1 && parm_depth > 1)
7368 /* We've been given an incomplete set of template arguments.
7371 template <class T> struct S1 {
7372 template <class U> struct S2 {};
7373 template <class U> struct S2<U*> {};
7376 we will be called with an ARGLIST of `U*', but the
7377 TEMPLATE will be `template <class T> template
7378 <class U> struct S1<T>::S2'. We must fill in the missing
7381 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7383 arg_depth = TMPL_ARGS_DEPTH (arglist);
7386 /* Now we should have enough arguments. */
7387 gcc_assert (parm_depth == arg_depth);
7389 /* From here on, we're only interested in the most general
7392 /* Calculate the BOUND_ARGS. These will be the args that are
7393 actually tsubst'd into the definition to create the
7397 /* We have multiple levels of arguments to coerce, at once. */
7399 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7401 tree bound_args = make_tree_vec (parm_depth);
7403 for (i = saved_depth,
7404 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7405 i > 0 && t != NULL_TREE;
7406 --i, t = TREE_CHAIN (t))
7409 if (i == saved_depth)
7410 a = coerce_template_parms (TREE_VALUE (t),
7413 /*require_all_args=*/true,
7414 /*use_default_args=*/true);
7416 /* Outer levels should have already been coerced. */
7417 a = TMPL_ARGS_LEVEL (arglist, i);
7419 /* Don't process further if one of the levels fails. */
7420 if (a == error_mark_node)
7422 /* Restore the ARGLIST to its full size. */
7423 TREE_VEC_LENGTH (arglist) = saved_depth;
7424 return error_mark_node;
7427 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7429 /* We temporarily reduce the length of the ARGLIST so
7430 that coerce_template_parms will see only the arguments
7431 corresponding to the template parameters it is
7433 TREE_VEC_LENGTH (arglist)--;
7436 /* Restore the ARGLIST to its full size. */
7437 TREE_VEC_LENGTH (arglist) = saved_depth;
7439 arglist = bound_args;
7443 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7444 INNERMOST_TEMPLATE_ARGS (arglist),
7447 /*require_all_args=*/true,
7448 /*use_default_args=*/true);
7450 if (arglist == error_mark_node)
7451 /* We were unable to bind the arguments. */
7452 return error_mark_node;
7454 /* In the scope of a template class, explicit references to the
7455 template class refer to the type of the template, not any
7456 instantiation of it. For example, in:
7458 template <class T> class C { void f(C<T>); }
7460 the `C<T>' is just the same as `C'. Outside of the
7461 class, however, such a reference is an instantiation. */
7463 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7464 || currently_open_class (template_type))
7465 /* comp_template_args is expensive, check it last. */
7466 && comp_template_args (TYPE_TI_ARGS (template_type),
7468 return template_type;
7470 /* If we already have this specialization, return it. */
7471 elt.tmpl = gen_tmpl;
7473 hash = hash_specialization (&elt);
7474 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7480 is_dependent_type = uses_template_parms (arglist);
7482 /* If the deduced arguments are invalid, then the binding
7484 if (!is_dependent_type
7485 && check_instantiated_args (gen_tmpl,
7486 INNERMOST_TEMPLATE_ARGS (arglist),
7488 return error_mark_node;
7490 if (!is_dependent_type
7491 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7492 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7493 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7495 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7496 DECL_NAME (gen_tmpl),
7497 /*tag_scope=*/ts_global);
7501 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7503 if (context == error_mark_node)
7504 return error_mark_node;
7507 context = global_namespace;
7509 /* Create the type. */
7510 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7512 if (!is_dependent_type)
7514 set_current_access_from_decl (TYPE_NAME (template_type));
7515 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7516 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7517 arglist, complain, in_decl),
7518 SCOPED_ENUM_P (template_type), NULL);
7522 /* We don't want to call start_enum for this type, since
7523 the values for the enumeration constants may involve
7524 template parameters. And, no one should be interested
7525 in the enumeration constants for such a type. */
7526 t = cxx_make_type (ENUMERAL_TYPE);
7527 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7529 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7530 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7531 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7533 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7535 /* The user referred to a specialization of an alias
7536 template represented by GEN_TMPL.
7538 [temp.alias]/2 says:
7540 When a template-id refers to the specialization of an
7541 alias template, it is equivalent to the associated
7542 type obtained by substitution of its
7543 template-arguments for the template-parameters in the
7544 type-id of the alias template. */
7546 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7547 /* Note that the call above (by indirectly calling
7548 register_specialization in tsubst_decl) registers the
7549 TYPE_DECL representing the specialization of the alias
7550 template. So next time someone substitutes ARGLIST for
7551 the template parms into the alias template (GEN_TMPL),
7552 she'll get that TYPE_DECL back. */
7554 if (t == error_mark_node)
7557 else if (CLASS_TYPE_P (template_type))
7559 t = make_class_type (TREE_CODE (template_type));
7560 CLASSTYPE_DECLARED_CLASS (t)
7561 = CLASSTYPE_DECLARED_CLASS (template_type);
7562 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7563 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7565 /* A local class. Make sure the decl gets registered properly. */
7566 if (context == current_function_decl)
7567 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7569 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7570 /* This instantiation is another name for the primary
7571 template type. Set the TYPE_CANONICAL field
7573 TYPE_CANONICAL (t) = template_type;
7574 else if (any_template_arguments_need_structural_equality_p (arglist))
7575 /* Some of the template arguments require structural
7576 equality testing, so this template class requires
7577 structural equality testing. */
7578 SET_TYPE_STRUCTURAL_EQUALITY (t);
7583 /* If we called start_enum or pushtag above, this information
7584 will already be set up. */
7587 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7589 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7590 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7591 DECL_SOURCE_LOCATION (type_decl)
7592 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7595 type_decl = TYPE_NAME (t);
7597 if (CLASS_TYPE_P (template_type))
7599 TREE_PRIVATE (type_decl)
7600 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7601 TREE_PROTECTED (type_decl)
7602 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7603 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7605 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7606 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7610 /* Let's consider the explicit specialization of a member
7611 of a class template specialization that is implicitely instantiated,
7616 template<class U> struct M {}; //#0
7621 struct S<int>::M<char> //#1
7625 [temp.expl.spec]/4 says this is valid.
7627 In this case, when we write:
7630 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7633 When we encounter #1, we want to store the partial instantiation
7634 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7636 For all cases other than this "explicit specialization of member of a
7637 class template", we just want to store the most general template into
7638 the CLASSTYPE_TI_TEMPLATE of M.
7640 This case of "explicit specialization of member of a class template"
7642 1/ the enclosing class is an instantiation of, and therefore not
7643 the same as, the context of the most general template, and
7644 2/ we aren't looking at the partial instantiation itself, i.e.
7645 the innermost arguments are not the same as the innermost parms of
7646 the most general template.
7648 So it's only when 1/ and 2/ happens that we want to use the partial
7649 instantiation of the member template in lieu of its most general
7652 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7653 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7654 /* the enclosing class must be an instantiation... */
7655 && CLASS_TYPE_P (context)
7656 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7658 tree partial_inst_args;
7659 TREE_VEC_LENGTH (arglist)--;
7660 ++processing_template_decl;
7662 tsubst (INNERMOST_TEMPLATE_ARGS
7663 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7664 arglist, complain, NULL_TREE);
7665 --processing_template_decl;
7666 TREE_VEC_LENGTH (arglist)++;
7667 use_partial_inst_tmpl =
7668 /*...and we must not be looking at the partial instantiation
7670 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7674 if (!use_partial_inst_tmpl)
7675 /* This case is easy; there are no member templates involved. */
7679 /* This is a full instantiation of a member template. Find
7680 the partial instantiation of which this is an instance. */
7682 /* Temporarily reduce by one the number of levels in the ARGLIST
7683 so as to avoid comparing the last set of arguments. */
7684 TREE_VEC_LENGTH (arglist)--;
7685 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7686 TREE_VEC_LENGTH (arglist)++;
7687 /* FOUND is either a proper class type, or an alias
7688 template specialization. In the later case, it's a
7689 TYPE_DECL, resulting from the substituting of arguments
7690 for parameters in the TYPE_DECL of the alias template
7691 done earlier. So be careful while getting the template
7693 found = TREE_CODE (found) == TYPE_DECL
7694 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7695 : CLASSTYPE_TI_TEMPLATE (found);
7698 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7701 slot = htab_find_slot_with_hash (type_specializations,
7702 &elt, hash, INSERT);
7703 entry = ggc_alloc_spec_entry ();
7707 /* Note this use of the partial instantiation so we can check it
7708 later in maybe_process_partial_specialization. */
7709 DECL_TEMPLATE_INSTANTIATIONS (templ)
7710 = tree_cons (arglist, t,
7711 DECL_TEMPLATE_INSTANTIATIONS (templ));
7713 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7714 /* Now that the type has been registered on the instantiations
7715 list, we set up the enumerators. Because the enumeration
7716 constants may involve the enumeration type itself, we make
7717 sure to register the type first, and then create the
7718 constants. That way, doing tsubst_expr for the enumeration
7719 constants won't result in recursive calls here; we'll find
7720 the instantiation and exit above. */
7721 tsubst_enum (template_type, t, arglist);
7723 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7724 /* If the type makes use of template parameters, the
7725 code that generates debugging information will crash. */
7726 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7728 /* Possibly limit visibility based on template args. */
7729 TREE_PUBLIC (type_decl) = 1;
7730 determine_visibility (type_decl);
7736 /* Wrapper for lookup_template_class_1. */
7739 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7740 int entering_scope, tsubst_flags_t complain)
7743 timevar_push (TV_TEMPLATE_INST);
7744 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7745 entering_scope, complain);
7746 timevar_pop (TV_TEMPLATE_INST);
7754 /* True when we should also visit template parameters that occur in
7755 non-deduced contexts. */
7756 bool include_nondeduced_p;
7757 struct pointer_set_t *visited;
7760 /* Called from for_each_template_parm via walk_tree. */
7763 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7766 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7767 tree_fn_t fn = pfd->fn;
7768 void *data = pfd->data;
7771 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7772 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7773 pfd->include_nondeduced_p))
7774 return error_mark_node;
7776 switch (TREE_CODE (t))
7779 if (TYPE_PTRMEMFUNC_P (t))
7785 if (!TYPE_TEMPLATE_INFO (t))
7787 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7788 fn, data, pfd->visited,
7789 pfd->include_nondeduced_p))
7790 return error_mark_node;
7794 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7795 fn, data, pfd->visited,
7796 pfd->include_nondeduced_p)
7797 || for_each_template_parm (TYPE_MAX_VALUE (t),
7798 fn, data, pfd->visited,
7799 pfd->include_nondeduced_p))
7800 return error_mark_node;
7804 /* Since we're not going to walk subtrees, we have to do this
7806 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7807 pfd->visited, pfd->include_nondeduced_p))
7808 return error_mark_node;
7812 /* Check the return type. */
7813 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7814 pfd->include_nondeduced_p))
7815 return error_mark_node;
7817 /* Check the parameter types. Since default arguments are not
7818 instantiated until they are needed, the TYPE_ARG_TYPES may
7819 contain expressions that involve template parameters. But,
7820 no-one should be looking at them yet. And, once they're
7821 instantiated, they don't contain template parameters, so
7822 there's no point in looking at them then, either. */
7826 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7827 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7828 pfd->visited, pfd->include_nondeduced_p))
7829 return error_mark_node;
7831 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7832 want walk_tree walking into them itself. */
7838 case UNDERLYING_TYPE:
7839 if (pfd->include_nondeduced_p
7840 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7842 pfd->include_nondeduced_p))
7843 return error_mark_node;
7848 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7849 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7850 pfd->visited, pfd->include_nondeduced_p))
7851 return error_mark_node;
7856 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7857 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7858 pfd->visited, pfd->include_nondeduced_p))
7859 return error_mark_node;
7860 if (DECL_CONTEXT (t)
7861 && pfd->include_nondeduced_p
7862 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7863 pfd->visited, pfd->include_nondeduced_p))
7864 return error_mark_node;
7867 case BOUND_TEMPLATE_TEMPLATE_PARM:
7868 /* Record template parameters such as `T' inside `TT<T>'. */
7869 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7870 pfd->include_nondeduced_p))
7871 return error_mark_node;
7874 case TEMPLATE_TEMPLATE_PARM:
7875 case TEMPLATE_TYPE_PARM:
7876 case TEMPLATE_PARM_INDEX:
7877 if (fn && (*fn)(t, data))
7878 return error_mark_node;
7880 return error_mark_node;
7884 /* A template template parameter is encountered. */
7885 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7886 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7887 pfd->include_nondeduced_p))
7888 return error_mark_node;
7890 /* Already substituted template template parameter */
7896 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7898 pfd->include_nondeduced_p))
7899 return error_mark_node;
7903 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7904 && pfd->include_nondeduced_p
7905 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7906 (TREE_TYPE (t)), fn, data,
7907 pfd->visited, pfd->include_nondeduced_p))
7908 return error_mark_node;
7913 /* If there's no type, then this thing must be some expression
7914 involving template parameters. */
7915 if (!fn && !TREE_TYPE (t))
7916 return error_mark_node;
7921 case IMPLICIT_CONV_EXPR:
7922 case REINTERPRET_CAST_EXPR:
7923 case CONST_CAST_EXPR:
7924 case STATIC_CAST_EXPR:
7925 case DYNAMIC_CAST_EXPR:
7929 case PSEUDO_DTOR_EXPR:
7931 return error_mark_node;
7938 /* We didn't find any template parameters we liked. */
7942 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7943 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7944 call FN with the parameter and the DATA.
7945 If FN returns nonzero, the iteration is terminated, and
7946 for_each_template_parm returns 1. Otherwise, the iteration
7947 continues. If FN never returns a nonzero value, the value
7948 returned by for_each_template_parm is 0. If FN is NULL, it is
7949 considered to be the function which always returns 1.
7951 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7952 parameters that occur in non-deduced contexts. When false, only
7953 visits those template parameters that can be deduced. */
7956 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7957 struct pointer_set_t *visited,
7958 bool include_nondeduced_p)
7960 struct pair_fn_data pfd;
7966 pfd.include_nondeduced_p = include_nondeduced_p;
7968 /* Walk the tree. (Conceptually, we would like to walk without
7969 duplicates, but for_each_template_parm_r recursively calls
7970 for_each_template_parm, so we would need to reorganize a fair
7971 bit to use walk_tree_without_duplicates, so we keep our own
7974 pfd.visited = visited;
7976 pfd.visited = pointer_set_create ();
7977 result = cp_walk_tree (&t,
7978 for_each_template_parm_r,
7980 pfd.visited) != NULL_TREE;
7985 pointer_set_destroy (pfd.visited);
7992 /* Returns true if T depends on any template parameter. */
7995 uses_template_parms (tree t)
7998 int saved_processing_template_decl;
8000 saved_processing_template_decl = processing_template_decl;
8001 if (!saved_processing_template_decl)
8002 processing_template_decl = 1;
8004 dependent_p = dependent_type_p (t);
8005 else if (TREE_CODE (t) == TREE_VEC)
8006 dependent_p = any_dependent_template_arguments_p (t);
8007 else if (TREE_CODE (t) == TREE_LIST)
8008 dependent_p = (uses_template_parms (TREE_VALUE (t))
8009 || uses_template_parms (TREE_CHAIN (t)));
8010 else if (TREE_CODE (t) == TYPE_DECL)
8011 dependent_p = dependent_type_p (TREE_TYPE (t));
8014 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
8015 || TREE_CODE (t) == OVERLOAD
8017 || TREE_CODE (t) == IDENTIFIER_NODE
8018 || TREE_CODE (t) == TRAIT_EXPR
8019 || TREE_CODE (t) == CONSTRUCTOR
8020 || CONSTANT_CLASS_P (t))
8021 dependent_p = (type_dependent_expression_p (t)
8022 || value_dependent_expression_p (t));
8025 gcc_assert (t == error_mark_node);
8026 dependent_p = false;
8029 processing_template_decl = saved_processing_template_decl;
8034 /* Returns true if T depends on any template parameter with level LEVEL. */
8037 uses_template_parms_level (tree t, int level)
8039 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
8040 /*include_nondeduced_p=*/true);
8043 /* Returns TRUE iff INST is an instantiation we don't need to do in an
8044 ill-formed translation unit, i.e. a variable or function that isn't
8045 usable in a constant expression. */
8048 neglectable_inst_p (tree d)
8051 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
8052 : decl_maybe_constant_var_p (d)));
8055 /* Returns TRUE iff we should refuse to instantiate DECL because it's
8056 neglectable and instantiated from within an erroneous instantiation. */
8059 limit_bad_template_recursion (tree decl)
8061 struct tinst_level *lev = current_tinst_level;
8062 int errs = errorcount + sorrycount;
8063 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
8066 for (; lev; lev = lev->next)
8067 if (neglectable_inst_p (lev->decl))
8070 return (lev && errs > lev->errors);
8073 static int tinst_depth;
8074 extern int max_tinst_depth;
8075 #ifdef GATHER_STATISTICS
8078 static GTY(()) struct tinst_level *last_error_tinst_level;
8080 /* We're starting to instantiate D; record the template instantiation context
8081 for diagnostics and to restore it later. */
8084 push_tinst_level (tree d)
8086 struct tinst_level *new_level;
8088 if (tinst_depth >= max_tinst_depth)
8090 last_error_tinst_level = current_tinst_level;
8091 if (TREE_CODE (d) == TREE_LIST)
8092 error ("template instantiation depth exceeds maximum of %d (use "
8093 "-ftemplate-depth= to increase the maximum) substituting %qS",
8094 max_tinst_depth, d);
8096 error ("template instantiation depth exceeds maximum of %d (use "
8097 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8098 max_tinst_depth, d);
8100 print_instantiation_context ();
8105 /* If the current instantiation caused problems, don't let it instantiate
8106 anything else. Do allow deduction substitution and decls usable in
8107 constant expressions. */
8108 if (limit_bad_template_recursion (d))
8111 new_level = ggc_alloc_tinst_level ();
8112 new_level->decl = d;
8113 new_level->locus = input_location;
8114 new_level->errors = errorcount+sorrycount;
8115 new_level->in_system_header_p = in_system_header;
8116 new_level->next = current_tinst_level;
8117 current_tinst_level = new_level;
8120 #ifdef GATHER_STATISTICS
8121 if (tinst_depth > depth_reached)
8122 depth_reached = tinst_depth;
8128 /* We're done instantiating this template; return to the instantiation
8132 pop_tinst_level (void)
8134 /* Restore the filename and line number stashed away when we started
8135 this instantiation. */
8136 input_location = current_tinst_level->locus;
8137 current_tinst_level = current_tinst_level->next;
8141 /* We're instantiating a deferred template; restore the template
8142 instantiation context in which the instantiation was requested, which
8143 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8146 reopen_tinst_level (struct tinst_level *level)
8148 struct tinst_level *t;
8151 for (t = level; t; t = t->next)
8154 current_tinst_level = level;
8156 if (current_tinst_level)
8157 current_tinst_level->errors = errorcount+sorrycount;
8161 /* Returns the TINST_LEVEL which gives the original instantiation
8164 struct tinst_level *
8165 outermost_tinst_level (void)
8167 struct tinst_level *level = current_tinst_level;
8170 level = level->next;
8174 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8177 parameter_of_template_p (tree parm, tree templ)
8182 if (!parm || !templ)
8185 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8186 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8188 parms = DECL_TEMPLATE_PARMS (templ);
8189 parms = INNERMOST_TEMPLATE_PARMS (parms);
8191 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8193 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8194 if (p == error_mark_node)
8198 || (DECL_INITIAL (parm)
8199 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8206 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8207 vector of template arguments, as for tsubst.
8209 Returns an appropriate tsubst'd friend declaration. */
8212 tsubst_friend_function (tree decl, tree args)
8216 if (TREE_CODE (decl) == FUNCTION_DECL
8217 && DECL_TEMPLATE_INSTANTIATION (decl)
8218 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8219 /* This was a friend declared with an explicit template
8220 argument list, e.g.:
8224 to indicate that f was a template instantiation, not a new
8225 function declaration. Now, we have to figure out what
8226 instantiation of what template. */
8228 tree template_id, arglist, fns;
8231 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8233 /* Friend functions are looked up in the containing namespace scope.
8234 We must enter that scope, to avoid finding member functions of the
8235 current class with same name. */
8236 push_nested_namespace (ns);
8237 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8238 tf_warning_or_error, NULL_TREE,
8239 /*integral_constant_expression_p=*/false);
8240 pop_nested_namespace (ns);
8241 arglist = tsubst (DECL_TI_ARGS (decl), args,
8242 tf_warning_or_error, NULL_TREE);
8243 template_id = lookup_template_function (fns, arglist);
8245 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8246 tmpl = determine_specialization (template_id, new_friend,
8248 /*need_member_template=*/0,
8249 TREE_VEC_LENGTH (args),
8251 return instantiate_template (tmpl, new_args, tf_error);
8254 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8256 /* The NEW_FRIEND will look like an instantiation, to the
8257 compiler, but is not an instantiation from the point of view of
8258 the language. For example, we might have had:
8260 template <class T> struct S {
8261 template <class U> friend void f(T, U);
8264 Then, in S<int>, template <class U> void f(int, U) is not an
8265 instantiation of anything. */
8266 if (new_friend == error_mark_node)
8267 return error_mark_node;
8269 DECL_USE_TEMPLATE (new_friend) = 0;
8270 if (TREE_CODE (decl) == TEMPLATE_DECL)
8272 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8273 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8274 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8277 /* The mangled name for the NEW_FRIEND is incorrect. The function
8278 is not a template instantiation and should not be mangled like
8279 one. Therefore, we forget the mangling here; we'll recompute it
8280 later if we need it. */
8281 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8283 SET_DECL_RTL (new_friend, NULL);
8284 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8287 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8290 tree new_friend_template_info;
8291 tree new_friend_result_template_info;
8293 int new_friend_is_defn;
8295 /* We must save some information from NEW_FRIEND before calling
8296 duplicate decls since that function will free NEW_FRIEND if
8298 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8299 new_friend_is_defn =
8300 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8301 (template_for_substitution (new_friend)))
8303 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8305 /* This declaration is a `primary' template. */
8306 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8308 new_friend_result_template_info
8309 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8312 new_friend_result_template_info = NULL_TREE;
8314 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8315 if (new_friend_is_defn)
8316 DECL_INITIAL (new_friend) = error_mark_node;
8318 /* Inside pushdecl_namespace_level, we will push into the
8319 current namespace. However, the friend function should go
8320 into the namespace of the template. */
8321 ns = decl_namespace_context (new_friend);
8322 push_nested_namespace (ns);
8323 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8324 pop_nested_namespace (ns);
8326 if (old_decl == error_mark_node)
8327 return error_mark_node;
8329 if (old_decl != new_friend)
8331 /* This new friend declaration matched an existing
8332 declaration. For example, given:
8334 template <class T> void f(T);
8335 template <class U> class C {
8336 template <class T> friend void f(T) {}
8339 the friend declaration actually provides the definition
8340 of `f', once C has been instantiated for some type. So,
8341 old_decl will be the out-of-class template declaration,
8342 while new_friend is the in-class definition.
8344 But, if `f' was called before this point, the
8345 instantiation of `f' will have DECL_TI_ARGS corresponding
8346 to `T' but not to `U', references to which might appear
8347 in the definition of `f'. Previously, the most general
8348 template for an instantiation of `f' was the out-of-class
8349 version; now it is the in-class version. Therefore, we
8350 run through all specialization of `f', adding to their
8351 DECL_TI_ARGS appropriately. In particular, they need a
8352 new set of outer arguments, corresponding to the
8353 arguments for this class instantiation.
8355 The same situation can arise with something like this:
8358 template <class T> class C {
8362 when `C<int>' is instantiated. Now, `f(int)' is defined
8365 if (!new_friend_is_defn)
8366 /* On the other hand, if the in-class declaration does
8367 *not* provide a definition, then we don't want to alter
8368 existing definitions. We can just leave everything
8373 tree new_template = TI_TEMPLATE (new_friend_template_info);
8374 tree new_args = TI_ARGS (new_friend_template_info);
8376 /* Overwrite whatever template info was there before, if
8377 any, with the new template information pertaining to
8379 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8381 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8383 /* We should have called reregister_specialization in
8385 gcc_assert (retrieve_specialization (new_template,
8389 /* Instantiate it if the global has already been used. */
8390 if (DECL_ODR_USED (old_decl))
8391 instantiate_decl (old_decl, /*defer_ok=*/true,
8392 /*expl_inst_class_mem_p=*/false);
8398 /* Indicate that the old function template is a partial
8400 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8401 = new_friend_result_template_info;
8403 gcc_assert (new_template
8404 == most_general_template (new_template));
8405 gcc_assert (new_template != old_decl);
8407 /* Reassign any specializations already in the hash table
8408 to the new more general template, and add the
8409 additional template args. */
8410 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8414 tree spec = TREE_VALUE (t);
8417 elt.tmpl = old_decl;
8418 elt.args = DECL_TI_ARGS (spec);
8419 elt.spec = NULL_TREE;
8421 htab_remove_elt (decl_specializations, &elt);
8424 = add_outermost_template_args (new_args,
8425 DECL_TI_ARGS (spec));
8427 register_specialization
8428 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8431 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8435 /* The information from NEW_FRIEND has been merged into OLD_DECL
8436 by duplicate_decls. */
8437 new_friend = old_decl;
8442 tree context = DECL_CONTEXT (new_friend);
8446 template <class T> class C {
8447 template <class U> friend void C1<U>::f (); // case 1
8448 friend void C2<T>::f (); // case 2
8450 we only need to make sure CONTEXT is a complete type for
8451 case 2. To distinguish between the two cases, we note that
8452 CONTEXT of case 1 remains dependent type after tsubst while
8453 this isn't true for case 2. */
8454 ++processing_template_decl;
8455 dependent_p = dependent_type_p (context);
8456 --processing_template_decl;
8459 && !complete_type_or_else (context, NULL_TREE))
8460 return error_mark_node;
8462 if (COMPLETE_TYPE_P (context))
8464 /* Check to see that the declaration is really present, and,
8465 possibly obtain an improved declaration. */
8466 tree fn = check_classfn (context,
8467 new_friend, NULL_TREE);
8477 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8478 template arguments, as for tsubst.
8480 Returns an appropriate tsubst'd friend type or error_mark_node on
8484 tsubst_friend_class (tree friend_tmpl, tree args)
8490 context = CP_DECL_CONTEXT (friend_tmpl);
8492 if (context != global_namespace)
8494 if (TREE_CODE (context) == NAMESPACE_DECL)
8495 push_nested_namespace (context);
8497 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8500 /* Look for a class template declaration. We look for hidden names
8501 because two friend declarations of the same template are the
8502 same. For example, in:
8505 template <typename> friend class F;
8507 template <typename> struct B {
8508 template <typename> friend class F;
8511 both F templates are the same. */
8512 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8513 /*block_p=*/true, 0,
8514 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8516 /* But, if we don't find one, it might be because we're in a
8517 situation like this:
8525 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8526 for `S<int>', not the TEMPLATE_DECL. */
8527 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8529 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8530 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8533 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8535 /* The friend template has already been declared. Just
8536 check to see that the declarations match, and install any new
8537 default parameters. We must tsubst the default parameters,
8538 of course. We only need the innermost template parameters
8539 because that is all that redeclare_class_template will look
8541 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8542 > TMPL_ARGS_DEPTH (args))
8545 location_t saved_input_location;
8546 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8547 args, tf_warning_or_error);
8549 saved_input_location = input_location;
8550 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8551 redeclare_class_template (TREE_TYPE (tmpl), parms);
8552 input_location = saved_input_location;
8556 friend_type = TREE_TYPE (tmpl);
8560 /* The friend template has not already been declared. In this
8561 case, the instantiation of the template class will cause the
8562 injection of this template into the global scope. */
8563 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8564 if (tmpl == error_mark_node)
8565 return error_mark_node;
8567 /* The new TMPL is not an instantiation of anything, so we
8568 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8569 the new type because that is supposed to be the corresponding
8570 template decl, i.e., TMPL. */
8571 DECL_USE_TEMPLATE (tmpl) = 0;
8572 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8573 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8574 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8575 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8577 /* Inject this template into the global scope. */
8578 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8581 if (context != global_namespace)
8583 if (TREE_CODE (context) == NAMESPACE_DECL)
8584 pop_nested_namespace (context);
8586 pop_nested_class ();
8592 /* Returns zero if TYPE cannot be completed later due to circularity.
8593 Otherwise returns one. */
8596 can_complete_type_without_circularity (tree type)
8598 if (type == NULL_TREE || type == error_mark_node)
8600 else if (COMPLETE_TYPE_P (type))
8602 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8603 return can_complete_type_without_circularity (TREE_TYPE (type));
8604 else if (CLASS_TYPE_P (type)
8605 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8611 /* Apply any attributes which had to be deferred until instantiation
8612 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8613 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8616 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8617 tree args, tsubst_flags_t complain, tree in_decl)
8619 tree last_dep = NULL_TREE;
8623 for (t = attributes; t; t = TREE_CHAIN (t))
8624 if (ATTR_IS_DEPENDENT (t))
8627 attributes = copy_list (attributes);
8631 if (DECL_P (*decl_p))
8633 if (TREE_TYPE (*decl_p) == error_mark_node)
8635 p = &DECL_ATTRIBUTES (*decl_p);
8638 p = &TYPE_ATTRIBUTES (*decl_p);
8642 tree late_attrs = NULL_TREE;
8643 tree *q = &late_attrs;
8645 for (*p = attributes; *p; )
8648 if (ATTR_IS_DEPENDENT (t))
8650 *p = TREE_CHAIN (t);
8651 TREE_CHAIN (t) = NULL_TREE;
8652 /* If the first attribute argument is an identifier, don't
8653 pass it through tsubst. Attributes like mode, format,
8654 cleanup and several target specific attributes expect it
8657 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8658 && TREE_VALUE (TREE_VALUE (t))
8659 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8660 == IDENTIFIER_NODE))
8663 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8665 /*integral_constant_expression_p=*/false);
8666 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8668 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8673 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8674 /*integral_constant_expression_p=*/false);
8676 q = &TREE_CHAIN (t);
8679 p = &TREE_CHAIN (t);
8682 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8686 /* Perform (or defer) access check for typedefs that were referenced
8687 from within the template TMPL code.
8688 This is a subroutine of instantiate_template and instantiate_class_template.
8689 TMPL is the template to consider and TARGS is the list of arguments of
8693 perform_typedefs_access_check (tree tmpl, tree targs)
8695 location_t saved_location;
8697 qualified_typedef_usage_t *iter;
8700 || (!CLASS_TYPE_P (tmpl)
8701 && TREE_CODE (tmpl) != FUNCTION_DECL))
8704 saved_location = input_location;
8705 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8706 get_types_needing_access_check (tmpl),
8709 tree type_decl = iter->typedef_decl;
8710 tree type_scope = iter->context;
8712 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8715 if (uses_template_parms (type_decl))
8716 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8717 if (uses_template_parms (type_scope))
8718 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8720 /* Make access check error messages point to the location
8721 of the use of the typedef. */
8722 input_location = iter->locus;
8723 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8724 type_decl, type_decl);
8726 input_location = saved_location;
8730 instantiate_class_template_1 (tree type)
8732 tree templ, args, pattern, t, member;
8736 unsigned int saved_maximum_field_alignment;
8738 if (type == error_mark_node)
8739 return error_mark_node;
8741 if (COMPLETE_OR_OPEN_TYPE_P (type)
8742 || uses_template_parms (type))
8745 /* Figure out which template is being instantiated. */
8746 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8747 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8749 /* Determine what specialization of the original template to
8751 t = most_specialized_class (type, templ, tf_warning_or_error);
8752 if (t == error_mark_node)
8754 TYPE_BEING_DEFINED (type) = 1;
8755 return error_mark_node;
8759 /* This TYPE is actually an instantiation of a partial
8760 specialization. We replace the innermost set of ARGS with
8761 the arguments appropriate for substitution. For example,
8764 template <class T> struct S {};
8765 template <class T> struct S<T*> {};
8767 and supposing that we are instantiating S<int*>, ARGS will
8768 presently be {int*} -- but we need {int}. */
8769 pattern = TREE_TYPE (t);
8770 args = TREE_PURPOSE (t);
8774 pattern = TREE_TYPE (templ);
8775 args = CLASSTYPE_TI_ARGS (type);
8778 /* If the template we're instantiating is incomplete, then clearly
8779 there's nothing we can do. */
8780 if (!COMPLETE_TYPE_P (pattern))
8783 /* If we've recursively instantiated too many templates, stop. */
8784 if (! push_tinst_level (type))
8787 /* Now we're really doing the instantiation. Mark the type as in
8788 the process of being defined. */
8789 TYPE_BEING_DEFINED (type) = 1;
8791 /* We may be in the middle of deferred access check. Disable
8793 push_deferring_access_checks (dk_no_deferred);
8795 push_to_top_level ();
8796 /* Use #pragma pack from the template context. */
8797 saved_maximum_field_alignment = maximum_field_alignment;
8798 maximum_field_alignment = TYPE_PRECISION (pattern);
8800 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8802 /* Set the input location to the most specialized template definition.
8803 This is needed if tsubsting causes an error. */
8804 typedecl = TYPE_MAIN_DECL (pattern);
8805 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8806 DECL_SOURCE_LOCATION (typedecl);
8808 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8809 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8810 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8811 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8812 if (ANON_AGGR_TYPE_P (pattern))
8813 SET_ANON_AGGR_TYPE_P (type);
8814 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8816 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8817 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8818 /* Adjust visibility for template arguments. */
8819 determine_visibility (TYPE_MAIN_DECL (type));
8821 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8823 pbinfo = TYPE_BINFO (pattern);
8825 /* We should never instantiate a nested class before its enclosing
8826 class; we need to look up the nested class by name before we can
8827 instantiate it, and that lookup should instantiate the enclosing
8829 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8830 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8832 base_list = NULL_TREE;
8833 if (BINFO_N_BASE_BINFOS (pbinfo))
8839 /* We must enter the scope containing the type, as that is where
8840 the accessibility of types named in dependent bases are
8842 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8844 /* Substitute into each of the bases to determine the actual
8846 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8849 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8850 tree expanded_bases = NULL_TREE;
8853 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8856 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8857 args, tf_error, NULL_TREE);
8858 if (expanded_bases == error_mark_node)
8861 len = TREE_VEC_LENGTH (expanded_bases);
8864 for (idx = 0; idx < len; idx++)
8867 /* Extract the already-expanded base class. */
8868 base = TREE_VEC_ELT (expanded_bases, idx);
8870 /* Substitute to figure out the base class. */
8871 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8874 if (base == error_mark_node)
8877 base_list = tree_cons (access, base, base_list);
8878 if (BINFO_VIRTUAL_P (pbase_binfo))
8879 TREE_TYPE (base_list) = integer_type_node;
8883 /* The list is now in reverse order; correct that. */
8884 base_list = nreverse (base_list);
8887 pop_scope (pushed_scope);
8889 /* Now call xref_basetypes to set up all the base-class
8891 xref_basetypes (type, base_list);
8893 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8894 (int) ATTR_FLAG_TYPE_IN_PLACE,
8895 args, tf_error, NULL_TREE);
8896 fixup_attribute_variants (type);
8898 /* Now that our base classes are set up, enter the scope of the
8899 class, so that name lookups into base classes, etc. will work
8900 correctly. This is precisely analogous to what we do in
8901 begin_class_definition when defining an ordinary non-template
8902 class, except we also need to push the enclosing classes. */
8903 push_nested_class (type);
8905 /* Now members are processed in the order of declaration. */
8906 for (member = CLASSTYPE_DECL_LIST (pattern);
8907 member; member = TREE_CHAIN (member))
8909 tree t = TREE_VALUE (member);
8911 if (TREE_PURPOSE (member))
8915 /* Build new CLASSTYPE_NESTED_UTDS. */
8918 bool class_template_p;
8920 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8921 && TYPE_LANG_SPECIFIC (t)
8922 && CLASSTYPE_IS_TEMPLATE (t));
8923 /* If the member is a class template, then -- even after
8924 substitution -- there may be dependent types in the
8925 template argument list for the class. We increment
8926 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8927 that function will assume that no types are dependent
8928 when outside of a template. */
8929 if (class_template_p)
8930 ++processing_template_decl;
8931 newtag = tsubst (t, args, tf_error, NULL_TREE);
8932 if (class_template_p)
8933 --processing_template_decl;
8934 if (newtag == error_mark_node)
8937 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8939 tree name = TYPE_IDENTIFIER (t);
8941 if (class_template_p)
8942 /* Unfortunately, lookup_template_class sets
8943 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8944 instantiation (i.e., for the type of a member
8945 template class nested within a template class.)
8946 This behavior is required for
8947 maybe_process_partial_specialization to work
8948 correctly, but is not accurate in this case;
8949 the TAG is not an instantiation of anything.
8950 (The corresponding TEMPLATE_DECL is an
8951 instantiation, but the TYPE is not.) */
8952 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8954 /* Now, we call pushtag to put this NEWTAG into the scope of
8955 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8956 pushtag calling push_template_decl. We don't have to do
8957 this for enums because it will already have been done in
8960 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8961 pushtag (name, newtag, /*tag_scope=*/ts_current);
8964 else if (TREE_CODE (t) == FUNCTION_DECL
8965 || DECL_FUNCTION_TEMPLATE_P (t))
8967 /* Build new TYPE_METHODS. */
8970 if (TREE_CODE (t) == TEMPLATE_DECL)
8971 ++processing_template_decl;
8972 r = tsubst (t, args, tf_error, NULL_TREE);
8973 if (TREE_CODE (t) == TEMPLATE_DECL)
8974 --processing_template_decl;
8975 set_current_access_from_decl (r);
8976 finish_member_declaration (r);
8977 /* Instantiate members marked with attribute used. */
8978 if (r != error_mark_node && DECL_PRESERVE_P (r))
8983 /* Build new TYPE_FIELDS. */
8984 if (TREE_CODE (t) == STATIC_ASSERT)
8987 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8988 tf_warning_or_error, NULL_TREE,
8989 /*integral_constant_expression_p=*/true);
8990 finish_static_assert (condition,
8991 STATIC_ASSERT_MESSAGE (t),
8992 STATIC_ASSERT_SOURCE_LOCATION (t),
8995 else if (TREE_CODE (t) != CONST_DECL)
8999 /* The file and line for this declaration, to
9000 assist in error message reporting. Since we
9001 called push_tinst_level above, we don't need to
9003 input_location = DECL_SOURCE_LOCATION (t);
9005 if (TREE_CODE (t) == TEMPLATE_DECL)
9006 ++processing_template_decl;
9007 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
9008 if (TREE_CODE (t) == TEMPLATE_DECL)
9009 --processing_template_decl;
9010 if (TREE_CODE (r) == VAR_DECL)
9014 [t]he initialization (and any associated
9015 side-effects) of a static data member does
9016 not occur unless the static data member is
9017 itself used in a way that requires the
9018 definition of the static data member to
9021 Therefore, we do not substitute into the
9022 initialized for the static data member here. */
9023 finish_static_data_member_decl
9026 /*init_const_expr_p=*/false,
9027 /*asmspec_tree=*/NULL_TREE,
9029 /* Instantiate members marked with attribute used. */
9030 if (r != error_mark_node && DECL_PRESERVE_P (r))
9033 else if (TREE_CODE (r) == FIELD_DECL)
9035 /* Determine whether R has a valid type and can be
9036 completed later. If R is invalid, then it is
9037 replaced by error_mark_node so that it will not be
9038 added to TYPE_FIELDS. */
9039 tree rtype = TREE_TYPE (r);
9040 if (can_complete_type_without_circularity (rtype))
9041 complete_type (rtype);
9043 if (!COMPLETE_TYPE_P (rtype))
9045 cxx_incomplete_type_error (r, rtype);
9046 r = error_mark_node;
9050 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
9051 such a thing will already have been added to the field
9052 list by tsubst_enum in finish_member_declaration in the
9053 CLASSTYPE_NESTED_UTDS case above. */
9054 if (!(TREE_CODE (r) == TYPE_DECL
9055 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
9056 && DECL_ARTIFICIAL (r)))
9058 set_current_access_from_decl (r);
9059 finish_member_declaration (r);
9066 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
9068 /* Build new CLASSTYPE_FRIEND_CLASSES. */
9070 tree friend_type = t;
9071 bool adjust_processing_template_decl = false;
9073 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9075 /* template <class T> friend class C; */
9076 friend_type = tsubst_friend_class (friend_type, args);
9077 adjust_processing_template_decl = true;
9079 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9081 /* template <class T> friend class C::D; */
9082 friend_type = tsubst (friend_type, args,
9083 tf_warning_or_error, NULL_TREE);
9084 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9085 friend_type = TREE_TYPE (friend_type);
9086 adjust_processing_template_decl = true;
9088 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9089 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9091 /* This could be either
9095 when dependent_type_p is false or
9097 template <class U> friend class T::C;
9100 friend_type = tsubst (friend_type, args,
9101 tf_warning_or_error, NULL_TREE);
9102 /* Bump processing_template_decl for correct
9103 dependent_type_p calculation. */
9104 ++processing_template_decl;
9105 if (dependent_type_p (friend_type))
9106 adjust_processing_template_decl = true;
9107 --processing_template_decl;
9109 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9110 && hidden_name_p (TYPE_NAME (friend_type)))
9114 where C hasn't been declared yet. Let's lookup name
9115 from namespace scope directly, bypassing any name that
9116 come from dependent base class. */
9117 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9119 /* The call to xref_tag_from_type does injection for friend
9121 push_nested_namespace (ns);
9123 xref_tag_from_type (friend_type, NULL_TREE,
9124 /*tag_scope=*/ts_current);
9125 pop_nested_namespace (ns);
9127 else if (uses_template_parms (friend_type))
9128 /* friend class C<T>; */
9129 friend_type = tsubst (friend_type, args,
9130 tf_warning_or_error, NULL_TREE);
9135 where C is already declared or
9137 friend class C<int>;
9139 We don't have to do anything in these cases. */
9141 if (adjust_processing_template_decl)
9142 /* Trick make_friend_class into realizing that the friend
9143 we're adding is a template, not an ordinary class. It's
9144 important that we use make_friend_class since it will
9145 perform some error-checking and output cross-reference
9147 ++processing_template_decl;
9149 if (friend_type != error_mark_node)
9150 make_friend_class (type, friend_type, /*complain=*/false);
9152 if (adjust_processing_template_decl)
9153 --processing_template_decl;
9157 /* Build new DECL_FRIENDLIST. */
9160 /* The file and line for this declaration, to
9161 assist in error message reporting. Since we
9162 called push_tinst_level above, we don't need to
9164 input_location = DECL_SOURCE_LOCATION (t);
9166 if (TREE_CODE (t) == TEMPLATE_DECL)
9168 ++processing_template_decl;
9169 push_deferring_access_checks (dk_no_check);
9172 r = tsubst_friend_function (t, args);
9173 add_friend (type, r, /*complain=*/false);
9174 if (TREE_CODE (t) == TEMPLATE_DECL)
9176 pop_deferring_access_checks ();
9177 --processing_template_decl;
9183 if (CLASSTYPE_LAMBDA_EXPR (type))
9185 tree decl = lambda_function (type);
9188 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9189 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9191 apply_lambda_return_type (lambda, void_type_node);
9192 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9194 instantiate_decl (decl, false, false);
9195 maybe_add_lambda_conv_op (type);
9198 gcc_assert (errorcount);
9201 /* Set the file and line number information to whatever is given for
9202 the class itself. This puts error messages involving generated
9203 implicit functions at a predictable point, and the same point
9204 that would be used for non-template classes. */
9205 input_location = DECL_SOURCE_LOCATION (typedecl);
9207 unreverse_member_declarations (type);
9208 finish_struct_1 (type);
9209 TYPE_BEING_DEFINED (type) = 0;
9211 /* We don't instantiate default arguments for member functions. 14.7.1:
9213 The implicit instantiation of a class template specialization causes
9214 the implicit instantiation of the declarations, but not of the
9215 definitions or default arguments, of the class member functions,
9216 member classes, static data members and member templates.... */
9218 /* Some typedefs referenced from within the template code need to be access
9219 checked at template instantiation time, i.e now. These types were
9220 added to the template at parsing time. Let's get those and perform
9221 the access checks then. */
9222 perform_typedefs_access_check (pattern, args);
9223 perform_deferred_access_checks ();
9224 pop_nested_class ();
9225 maximum_field_alignment = saved_maximum_field_alignment;
9226 pop_from_top_level ();
9227 pop_deferring_access_checks ();
9230 /* The vtable for a template class can be emitted in any translation
9231 unit in which the class is instantiated. When there is no key
9232 method, however, finish_struct_1 will already have added TYPE to
9233 the keyed_classes list. */
9234 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9235 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9240 /* Wrapper for instantiate_class_template_1. */
9243 instantiate_class_template (tree type)
9246 timevar_push (TV_TEMPLATE_INST);
9247 ret = instantiate_class_template_1 (type);
9248 timevar_pop (TV_TEMPLATE_INST);
9253 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9259 else if (TYPE_P (t))
9260 r = tsubst (t, args, complain, in_decl);
9263 if (!(complain & tf_warning))
9264 ++c_inhibit_evaluation_warnings;
9265 r = tsubst_expr (t, args, complain, in_decl,
9266 /*integral_constant_expression_p=*/true);
9267 if (!(complain & tf_warning))
9268 --c_inhibit_evaluation_warnings;
9269 /* Preserve the raw-reference nature of T. */
9270 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9271 && REFERENCE_REF_P (r))
9272 r = TREE_OPERAND (r, 0);
9277 /* Given a function parameter pack TMPL_PARM and some function parameters
9278 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9279 and set *SPEC_P to point at the next point in the list. */
9282 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9284 /* Collect all of the extra "packed" parameters into an
9288 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9289 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9290 tree spec_parm = *spec_p;
9293 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9295 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9298 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9299 parmvec = make_tree_vec (len);
9300 parmtypevec = make_tree_vec (len);
9301 spec_parm = *spec_p;
9302 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9304 TREE_VEC_ELT (parmvec, i) = spec_parm;
9305 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9308 /* Build the argument packs. */
9309 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9310 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9311 TREE_TYPE (argpack) = argtypepack;
9312 *spec_p = spec_parm;
9317 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9318 NONTYPE_ARGUMENT_PACK. */
9321 make_fnparm_pack (tree spec_parm)
9323 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9326 /* Substitute ARGS into T, which is an pack expansion
9327 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9328 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9329 (if only a partial substitution could be performed) or
9330 ERROR_MARK_NODE if there was an error. */
9332 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9336 tree pack, packs = NULL_TREE;
9337 bool unsubstituted_packs = false;
9338 bool real_packs = false;
9339 int missing_level = 0;
9342 htab_t saved_local_specializations = NULL;
9343 bool need_local_specializations = false;
9346 gcc_assert (PACK_EXPANSION_P (t));
9347 pattern = PACK_EXPANSION_PATTERN (t);
9349 /* Add in any args remembered from an earlier partial instantiation. */
9350 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9352 levels = TMPL_ARGS_DEPTH (args);
9354 /* Determine the argument packs that will instantiate the parameter
9355 packs used in the expansion expression. While we're at it,
9356 compute the number of arguments to be expanded and make sure it
9358 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9359 pack = TREE_CHAIN (pack))
9361 tree parm_pack = TREE_VALUE (pack);
9362 tree arg_pack = NULL_TREE;
9363 tree orig_arg = NULL_TREE;
9366 if (TREE_CODE (parm_pack) == BASES)
9368 if (BASES_DIRECT (parm_pack))
9369 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9370 args, complain, in_decl, false));
9372 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9373 args, complain, in_decl, false));
9375 if (TREE_CODE (parm_pack) == PARM_DECL)
9377 if (PACK_EXPANSION_LOCAL_P (t))
9378 arg_pack = retrieve_local_specialization (parm_pack);
9381 /* We can't rely on local_specializations for a parameter
9382 name used later in a function declaration (such as in a
9383 late-specified return type). Even if it exists, it might
9384 have the wrong value for a recursive call. Just make a
9385 dummy decl, since it's only used for its type. */
9386 arg_pack = tsubst_decl (parm_pack, args, complain);
9387 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9388 /* Partial instantiation of the parm_pack, we can't build
9389 up an argument pack yet. */
9390 arg_pack = NULL_TREE;
9392 arg_pack = make_fnparm_pack (arg_pack);
9393 need_local_specializations = true;
9399 template_parm_level_and_index (parm_pack, &level, &idx);
9401 if (level <= levels)
9402 arg_pack = TMPL_ARG (args, level, idx);
9405 orig_arg = arg_pack;
9406 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9407 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9409 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9410 /* This can only happen if we forget to expand an argument
9411 pack somewhere else. Just return an error, silently. */
9413 result = make_tree_vec (1);
9414 TREE_VEC_ELT (result, 0) = error_mark_node;
9418 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9419 /* The argument pack that the parameter maps to is just an
9420 expansion of the parameter itself, such as one would find
9421 in the implicit typedef of a class inside the class itself.
9422 Consider this parameter "unsubstituted", so that we will
9423 maintain the outer pack expansion. */
9424 arg_pack = NULL_TREE;
9429 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9431 /* Don't bother trying to do a partial substitution with
9432 incomplete packs; we'll try again after deduction. */
9433 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9438 else if (len != my_len)
9440 if (!(complain & tf_error))
9441 /* Fail quietly. */;
9442 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9443 error ("mismatched argument pack lengths while expanding "
9447 error ("mismatched argument pack lengths while expanding "
9450 return error_mark_node;
9453 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9454 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9456 /* This isn't a real argument pack yet. */;
9460 /* Keep track of the parameter packs and their corresponding
9462 packs = tree_cons (parm_pack, arg_pack, packs);
9463 TREE_TYPE (packs) = orig_arg;
9467 /* We can't substitute for this parameter pack. We use a flag as
9468 well as the missing_level counter because function parameter
9469 packs don't have a level. */
9470 unsubstituted_packs = true;
9471 if (!missing_level || missing_level > level)
9472 missing_level = level;
9476 /* We cannot expand this expansion expression, because we don't have
9477 all of the argument packs we need. */
9478 if (unsubstituted_packs)
9482 /* We got some full packs, but we can't substitute them in until we
9483 have values for all the packs. So remember these until then. */
9486 t = make_pack_expansion (pattern);
9488 /* The call to add_to_template_args above assumes no overlap
9489 between saved args and new args, so prune away any fake
9490 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9491 if (missing_level && levels >= missing_level)
9493 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9494 && missing_level > 1);
9495 TREE_VEC_LENGTH (args) = missing_level - 1;
9496 save_args = copy_node (args);
9497 TREE_VEC_LENGTH (args) = levels;
9502 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9506 /* There were no real arguments, we're just replacing a parameter
9507 pack with another version of itself. Substitute into the
9508 pattern and return a PACK_EXPANSION_*. The caller will need to
9510 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9511 t = tsubst_expr (pattern, args, complain, in_decl,
9512 /*integral_constant_expression_p=*/false);
9514 t = tsubst (pattern, args, complain, in_decl);
9515 t = make_pack_expansion (t);
9520 /* We could not find any argument packs that work. */
9522 return error_mark_node;
9524 if (need_local_specializations)
9526 /* We're in a late-specified return type, so create our own local
9527 specializations table; the current table is either NULL or (in the
9528 case of recursive unification) might have bindings that we don't
9529 want to use or alter. */
9530 saved_local_specializations = local_specializations;
9531 local_specializations = htab_create (37,
9532 hash_local_specialization,
9533 eq_local_specializations,
9537 /* For each argument in each argument pack, substitute into the
9539 result = make_tree_vec (len);
9540 for (i = 0; i < len; ++i)
9542 /* For parameter pack, change the substitution of the parameter
9543 pack to the ith argument in its argument pack, then expand
9545 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9547 tree parm = TREE_PURPOSE (pack);
9550 /* Select the Ith argument from the pack. */
9551 if (TREE_CODE (parm) == PARM_DECL)
9555 arg = make_node (ARGUMENT_PACK_SELECT);
9556 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9558 register_local_specialization (arg, parm);
9561 arg = retrieve_local_specialization (parm);
9566 template_parm_level_and_index (parm, &level, &idx);
9570 arg = make_node (ARGUMENT_PACK_SELECT);
9571 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9572 /* Update the corresponding argument. */
9573 TMPL_ARG (args, level, idx) = arg;
9576 /* Re-use the ARGUMENT_PACK_SELECT. */
9577 arg = TMPL_ARG (args, level, idx);
9579 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9582 /* Substitute into the PATTERN with the altered arguments. */
9583 if (!TYPE_P (pattern))
9584 TREE_VEC_ELT (result, i) =
9585 tsubst_expr (pattern, args, complain, in_decl,
9586 /*integral_constant_expression_p=*/false);
9588 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9590 if (TREE_VEC_ELT (result, i) == error_mark_node)
9592 result = error_mark_node;
9597 /* Update ARGS to restore the substitution from parameter packs to
9598 their argument packs. */
9599 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9601 tree parm = TREE_PURPOSE (pack);
9603 if (TREE_CODE (parm) == PARM_DECL)
9604 register_local_specialization (TREE_TYPE (pack), parm);
9608 template_parm_level_and_index (parm, &level, &idx);
9610 /* Update the corresponding argument. */
9611 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9612 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9615 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9619 if (need_local_specializations)
9621 htab_delete (local_specializations);
9622 local_specializations = saved_local_specializations;
9628 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9629 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9630 parameter packs; all parms generated from a function parameter pack will
9631 have the same DECL_PARM_INDEX. */
9634 get_pattern_parm (tree parm, tree tmpl)
9636 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9639 if (DECL_ARTIFICIAL (parm))
9641 for (patparm = DECL_ARGUMENTS (pattern);
9642 patparm; patparm = DECL_CHAIN (patparm))
9643 if (DECL_ARTIFICIAL (patparm)
9644 && DECL_NAME (parm) == DECL_NAME (patparm))
9649 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9650 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9651 gcc_assert (DECL_PARM_INDEX (patparm)
9652 == DECL_PARM_INDEX (parm));
9658 /* Substitute ARGS into the vector or list of template arguments T. */
9661 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9664 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9667 if (t == error_mark_node)
9668 return error_mark_node;
9670 len = TREE_VEC_LENGTH (t);
9671 elts = XALLOCAVEC (tree, len);
9673 for (i = 0; i < len; i++)
9675 tree orig_arg = TREE_VEC_ELT (t, i);
9678 if (TREE_CODE (orig_arg) == TREE_VEC)
9679 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9680 else if (PACK_EXPANSION_P (orig_arg))
9682 /* Substitute into an expansion expression. */
9683 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9685 if (TREE_CODE (new_arg) == TREE_VEC)
9686 /* Add to the expanded length adjustment the number of
9687 expanded arguments. We subtract one from this
9688 measurement, because the argument pack expression
9689 itself is already counted as 1 in
9690 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9691 the argument pack is empty. */
9692 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9694 else if (ARGUMENT_PACK_P (orig_arg))
9696 /* Substitute into each of the arguments. */
9697 new_arg = TYPE_P (orig_arg)
9698 ? cxx_make_type (TREE_CODE (orig_arg))
9699 : make_node (TREE_CODE (orig_arg));
9701 SET_ARGUMENT_PACK_ARGS (
9703 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9704 args, complain, in_decl));
9706 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9707 new_arg = error_mark_node;
9709 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9710 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9712 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9714 if (TREE_TYPE (new_arg) == error_mark_node)
9715 new_arg = error_mark_node;
9719 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9721 if (new_arg == error_mark_node)
9722 return error_mark_node;
9725 if (new_arg != orig_arg)
9732 /* Make space for the expanded arguments coming from template
9734 t = make_tree_vec (len + expanded_len_adjust);
9735 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9736 arguments for a member template.
9737 In that case each TREE_VEC in ORIG_T represents a level of template
9738 arguments, and ORIG_T won't carry any non defaulted argument count.
9739 It will rather be the nested TREE_VECs that will carry one.
9740 In other words, ORIG_T carries a non defaulted argument count only
9741 if it doesn't contain any nested TREE_VEC. */
9742 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9744 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9745 count += expanded_len_adjust;
9746 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9748 for (i = 0, out = 0; i < len; i++)
9750 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9751 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9752 && TREE_CODE (elts[i]) == TREE_VEC)
9756 /* Now expand the template argument pack "in place". */
9757 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9758 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9762 TREE_VEC_ELT (t, out) = elts[i];
9770 /* Return the result of substituting ARGS into the template parameters
9771 given by PARMS. If there are m levels of ARGS and m + n levels of
9772 PARMS, then the result will contain n levels of PARMS. For
9773 example, if PARMS is `template <class T> template <class U>
9774 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9775 result will be `template <int*, double, class V>'. */
9778 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9783 /* When substituting into a template, we must set
9784 PROCESSING_TEMPLATE_DECL as the template parameters may be
9785 dependent if they are based on one-another, and the dependency
9786 predicates are short-circuit outside of templates. */
9787 ++processing_template_decl;
9789 for (new_parms = &r;
9790 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9791 new_parms = &(TREE_CHAIN (*new_parms)),
9792 parms = TREE_CHAIN (parms))
9795 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9798 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9802 if (parms == error_mark_node)
9805 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9807 if (tuple == error_mark_node)
9810 TREE_VEC_ELT (new_vec, i) =
9811 tsubst_template_parm (tuple, args, complain);
9815 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9816 - TMPL_ARGS_DEPTH (args)),
9817 new_vec, NULL_TREE);
9820 --processing_template_decl;
9825 /* Return the result of substituting ARGS into one template parameter
9826 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9827 parameter and which TREE_PURPOSE is the default argument of the
9828 template parameter. */
9831 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9833 tree default_value, parm_decl;
9835 if (args == NULL_TREE
9837 || t == error_mark_node)
9840 gcc_assert (TREE_CODE (t) == TREE_LIST);
9842 default_value = TREE_PURPOSE (t);
9843 parm_decl = TREE_VALUE (t);
9845 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9846 if (TREE_CODE (parm_decl) == PARM_DECL
9847 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9848 parm_decl = error_mark_node;
9849 default_value = tsubst_template_arg (default_value, args,
9850 complain, NULL_TREE);
9852 return build_tree_list (default_value, parm_decl);
9855 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9856 type T. If T is not an aggregate or enumeration type, it is
9857 handled as if by tsubst. IN_DECL is as for tsubst. If
9858 ENTERING_SCOPE is nonzero, T is the context for a template which
9859 we are presently tsubst'ing. Return the substituted value. */
9862 tsubst_aggr_type (tree t,
9864 tsubst_flags_t complain,
9871 switch (TREE_CODE (t))
9874 if (TYPE_PTRMEMFUNC_P (t))
9875 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9877 /* Else fall through. */
9880 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9885 int saved_unevaluated_operand;
9886 int saved_inhibit_evaluation_warnings;
9888 /* In "sizeof(X<I>)" we need to evaluate "I". */
9889 saved_unevaluated_operand = cp_unevaluated_operand;
9890 cp_unevaluated_operand = 0;
9891 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9892 c_inhibit_evaluation_warnings = 0;
9894 /* First, determine the context for the type we are looking
9896 context = TYPE_CONTEXT (t);
9897 if (context && TYPE_P (context))
9899 context = tsubst_aggr_type (context, args, complain,
9900 in_decl, /*entering_scope=*/1);
9901 /* If context is a nested class inside a class template,
9902 it may still need to be instantiated (c++/33959). */
9903 context = complete_type (context);
9906 /* Then, figure out what arguments are appropriate for the
9907 type we are trying to find. For example, given:
9909 template <class T> struct S;
9910 template <class T, class U> void f(T, U) { S<U> su; }
9912 and supposing that we are instantiating f<int, double>,
9913 then our ARGS will be {int, double}, but, when looking up
9914 S we only want {double}. */
9915 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9917 if (argvec == error_mark_node)
9918 r = error_mark_node;
9921 r = lookup_template_class (t, argvec, in_decl, context,
9922 entering_scope, complain);
9923 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9926 cp_unevaluated_operand = saved_unevaluated_operand;
9927 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9932 /* This is not a template type, so there's nothing to do. */
9936 return tsubst (t, args, complain, in_decl);
9940 /* Substitute into the default argument ARG (a default argument for
9941 FN), which has the indicated TYPE. */
9944 tsubst_default_argument (tree fn, tree type, tree arg)
9946 tree saved_class_ptr = NULL_TREE;
9947 tree saved_class_ref = NULL_TREE;
9949 /* This can happen in invalid code. */
9950 if (TREE_CODE (arg) == DEFAULT_ARG)
9953 /* This default argument came from a template. Instantiate the
9954 default argument here, not in tsubst. In the case of
9963 we must be careful to do name lookup in the scope of S<T>,
9964 rather than in the current class. */
9965 push_access_scope (fn);
9966 /* The "this" pointer is not valid in a default argument. */
9969 saved_class_ptr = current_class_ptr;
9970 cp_function_chain->x_current_class_ptr = NULL_TREE;
9971 saved_class_ref = current_class_ref;
9972 cp_function_chain->x_current_class_ref = NULL_TREE;
9975 push_deferring_access_checks(dk_no_deferred);
9976 /* The default argument expression may cause implicitly defined
9977 member functions to be synthesized, which will result in garbage
9978 collection. We must treat this situation as if we were within
9979 the body of function so as to avoid collecting live data on the
9982 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9983 tf_warning_or_error, NULL_TREE,
9984 /*integral_constant_expression_p=*/false);
9986 pop_deferring_access_checks();
9988 /* Restore the "this" pointer. */
9991 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9992 cp_function_chain->x_current_class_ref = saved_class_ref;
9995 /* Make sure the default argument is reasonable. */
9996 arg = check_default_argument (type, arg);
9998 pop_access_scope (fn);
10003 /* Substitute into all the default arguments for FN. */
10006 tsubst_default_arguments (tree fn)
10011 tmpl_args = DECL_TI_ARGS (fn);
10013 /* If this function is not yet instantiated, we certainly don't need
10014 its default arguments. */
10015 if (uses_template_parms (tmpl_args))
10017 /* Don't do this again for clones. */
10018 if (DECL_CLONED_FUNCTION_P (fn))
10021 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
10023 arg = TREE_CHAIN (arg))
10024 if (TREE_PURPOSE (arg))
10025 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
10027 TREE_PURPOSE (arg));
10030 /* Substitute the ARGS into the T, which is a _DECL. Return the
10031 result of the substitution. Issue error and warning messages under
10032 control of COMPLAIN. */
10035 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
10037 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
10038 location_t saved_loc;
10039 tree r = NULL_TREE;
10041 hashval_t hash = 0;
10043 /* Set the filename and linenumber to improve error-reporting. */
10044 saved_loc = input_location;
10045 input_location = DECL_SOURCE_LOCATION (t);
10047 switch (TREE_CODE (t))
10049 case TEMPLATE_DECL:
10051 /* We can get here when processing a member function template,
10052 member class template, or template template parameter. */
10053 tree decl = DECL_TEMPLATE_RESULT (t);
10058 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10060 /* Template template parameter is treated here. */
10061 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10062 if (new_type == error_mark_node)
10063 RETURN (error_mark_node);
10066 DECL_CHAIN (r) = NULL_TREE;
10067 TREE_TYPE (r) = new_type;
10068 DECL_TEMPLATE_RESULT (r)
10069 = build_decl (DECL_SOURCE_LOCATION (decl),
10070 TYPE_DECL, DECL_NAME (decl), new_type);
10071 DECL_TEMPLATE_PARMS (r)
10072 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10074 TYPE_NAME (new_type) = r;
10078 /* We might already have an instance of this template.
10079 The ARGS are for the surrounding class type, so the
10080 full args contain the tsubst'd args for the context,
10081 plus the innermost args from the template decl. */
10082 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10083 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10084 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10085 /* Because this is a template, the arguments will still be
10086 dependent, even after substitution. If
10087 PROCESSING_TEMPLATE_DECL is not set, the dependency
10088 predicates will short-circuit. */
10089 ++processing_template_decl;
10090 full_args = tsubst_template_args (tmpl_args, args,
10091 complain, in_decl);
10092 --processing_template_decl;
10093 if (full_args == error_mark_node)
10094 RETURN (error_mark_node);
10096 /* If this is a default template template argument,
10097 tsubst might not have changed anything. */
10098 if (full_args == tmpl_args)
10101 hash = hash_tmpl_and_args (t, full_args);
10102 spec = retrieve_specialization (t, full_args, hash);
10103 if (spec != NULL_TREE)
10109 /* Make a new template decl. It will be similar to the
10110 original, but will record the current template arguments.
10111 We also create a new function declaration, which is just
10112 like the old one, but points to this new template, rather
10113 than the old one. */
10115 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10116 DECL_CHAIN (r) = NULL_TREE;
10118 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10120 if (TREE_CODE (decl) == TYPE_DECL
10121 && !TYPE_DECL_ALIAS_P (decl))
10124 ++processing_template_decl;
10125 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10126 --processing_template_decl;
10127 if (new_type == error_mark_node)
10128 RETURN (error_mark_node);
10130 TREE_TYPE (r) = new_type;
10131 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10132 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10133 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10134 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10139 ++processing_template_decl;
10140 new_decl = tsubst (decl, args, complain, in_decl);
10141 --processing_template_decl;
10142 if (new_decl == error_mark_node)
10143 RETURN (error_mark_node);
10145 DECL_TEMPLATE_RESULT (r) = new_decl;
10146 DECL_TI_TEMPLATE (new_decl) = r;
10147 TREE_TYPE (r) = TREE_TYPE (new_decl);
10148 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10149 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10152 SET_DECL_IMPLICIT_INSTANTIATION (r);
10153 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10154 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10156 /* The template parameters for this new template are all the
10157 template parameters for the old template, except the
10158 outermost level of parameters. */
10159 DECL_TEMPLATE_PARMS (r)
10160 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10163 if (PRIMARY_TEMPLATE_P (t))
10164 DECL_PRIMARY_TEMPLATE (r) = r;
10166 if (TREE_CODE (decl) != TYPE_DECL)
10167 /* Record this non-type partial instantiation. */
10168 register_specialization (r, t,
10169 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10174 case FUNCTION_DECL:
10177 tree argvec = NULL_TREE;
10185 /* Nobody should be tsubst'ing into non-template functions. */
10186 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10188 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10193 /* If T is not dependent, just return it. We have to
10194 increment PROCESSING_TEMPLATE_DECL because
10195 value_dependent_expression_p assumes that nothing is
10196 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10197 ++processing_template_decl;
10198 dependent_p = value_dependent_expression_p (t);
10199 --processing_template_decl;
10203 /* Calculate the most general template of which R is a
10204 specialization, and the complete set of arguments used to
10206 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10207 argvec = tsubst_template_args (DECL_TI_ARGS
10208 (DECL_TEMPLATE_RESULT
10209 (DECL_TI_TEMPLATE (t))),
10210 args, complain, in_decl);
10211 if (argvec == error_mark_node)
10212 RETURN (error_mark_node);
10214 /* Check to see if we already have this specialization. */
10215 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10216 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10224 /* We can see more levels of arguments than parameters if
10225 there was a specialization of a member template, like
10228 template <class T> struct S { template <class U> void f(); }
10229 template <> template <class U> void S<int>::f(U);
10231 Here, we'll be substituting into the specialization,
10232 because that's where we can find the code we actually
10233 want to generate, but we'll have enough arguments for
10234 the most general template.
10236 We also deal with the peculiar case:
10238 template <class T> struct S {
10239 template <class U> friend void f();
10241 template <class U> void f() {}
10243 template void f<double>();
10245 Here, the ARGS for the instantiation of will be {int,
10246 double}. But, we only need as many ARGS as there are
10247 levels of template parameters in CODE_PATTERN. We are
10248 careful not to get fooled into reducing the ARGS in
10251 template <class T> struct S { template <class U> void f(U); }
10252 template <class T> template <> void S<T>::f(int) {}
10254 which we can spot because the pattern will be a
10255 specialization in this case. */
10256 args_depth = TMPL_ARGS_DEPTH (args);
10258 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10259 if (args_depth > parms_depth
10260 && !DECL_TEMPLATE_SPECIALIZATION (t))
10261 args = get_innermost_template_args (args, parms_depth);
10265 /* This special case arises when we have something like this:
10267 template <class T> struct S {
10268 friend void f<int>(int, double);
10271 Here, the DECL_TI_TEMPLATE for the friend declaration
10272 will be an IDENTIFIER_NODE. We are being called from
10273 tsubst_friend_function, and we want only to create a
10274 new decl (R) with appropriate types so that we can call
10275 determine_specialization. */
10276 gen_tmpl = NULL_TREE;
10279 if (DECL_CLASS_SCOPE_P (t))
10281 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10285 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10286 complain, t, /*entering_scope=*/1);
10291 ctx = DECL_CONTEXT (t);
10293 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10294 if (type == error_mark_node)
10295 RETURN (error_mark_node);
10297 /* We do NOT check for matching decls pushed separately at this
10298 point, as they may not represent instantiations of this
10299 template, and in any case are considered separate under the
10302 DECL_USE_TEMPLATE (r) = 0;
10303 TREE_TYPE (r) = type;
10304 /* Clear out the mangled name and RTL for the instantiation. */
10305 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10306 SET_DECL_RTL (r, NULL);
10307 /* Leave DECL_INITIAL set on deleted instantiations. */
10308 if (!DECL_DELETED_FN (r))
10309 DECL_INITIAL (r) = NULL_TREE;
10310 DECL_CONTEXT (r) = ctx;
10312 if (member && DECL_CONV_FN_P (r))
10313 /* Type-conversion operator. Reconstruct the name, in
10314 case it's the name of one of the template's parameters. */
10315 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10317 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10319 DECL_RESULT (r) = NULL_TREE;
10321 TREE_STATIC (r) = 0;
10322 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10323 DECL_EXTERNAL (r) = 1;
10324 /* If this is an instantiation of a function with internal
10325 linkage, we already know what object file linkage will be
10326 assigned to the instantiation. */
10327 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10328 DECL_DEFER_OUTPUT (r) = 0;
10329 DECL_CHAIN (r) = NULL_TREE;
10330 DECL_PENDING_INLINE_INFO (r) = 0;
10331 DECL_PENDING_INLINE_P (r) = 0;
10332 DECL_SAVED_TREE (r) = NULL_TREE;
10333 DECL_STRUCT_FUNCTION (r) = NULL;
10335 /* We'll re-clone as appropriate in instantiate_template. */
10336 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10338 /* If we aren't complaining now, return on error before we register
10339 the specialization so that we'll complain eventually. */
10340 if ((complain & tf_error) == 0
10341 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10342 && !grok_op_properties (r, /*complain=*/false))
10343 RETURN (error_mark_node);
10345 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10346 this in the special friend case mentioned above where
10347 GEN_TMPL is NULL. */
10350 DECL_TEMPLATE_INFO (r)
10351 = build_template_info (gen_tmpl, argvec);
10352 SET_DECL_IMPLICIT_INSTANTIATION (r);
10353 register_specialization (r, gen_tmpl, argvec, false, hash);
10355 /* We're not supposed to instantiate default arguments
10356 until they are called, for a template. But, for a
10359 template <class T> void f ()
10360 { extern void g(int i = T()); }
10362 we should do the substitution when the template is
10363 instantiated. We handle the member function case in
10364 instantiate_class_template since the default arguments
10365 might refer to other members of the class. */
10367 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10368 && !uses_template_parms (argvec))
10369 tsubst_default_arguments (r);
10372 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10374 /* Copy the list of befriending classes. */
10375 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10377 friends = &TREE_CHAIN (*friends))
10379 *friends = copy_node (*friends);
10380 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10385 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10387 maybe_retrofit_in_chrg (r);
10388 if (DECL_CONSTRUCTOR_P (r))
10389 grok_ctor_properties (ctx, r);
10390 /* If this is an instantiation of a member template, clone it.
10391 If it isn't, that'll be handled by
10392 clone_constructors_and_destructors. */
10393 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10394 clone_function_decl (r, /*update_method_vec_p=*/0);
10396 else if ((complain & tf_error) != 0
10397 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10398 && !grok_op_properties (r, /*complain=*/true))
10399 RETURN (error_mark_node);
10401 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10402 SET_DECL_FRIEND_CONTEXT (r,
10403 tsubst (DECL_FRIEND_CONTEXT (t),
10404 args, complain, in_decl));
10406 /* Possibly limit visibility based on template args. */
10407 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10408 if (DECL_VISIBILITY_SPECIFIED (t))
10410 DECL_VISIBILITY_SPECIFIED (r) = 0;
10411 DECL_ATTRIBUTES (r)
10412 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10414 determine_visibility (r);
10415 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10416 && !processing_template_decl)
10417 defaulted_late_check (r);
10419 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10420 args, complain, in_decl);
10426 tree type = NULL_TREE;
10428 tree expanded_types = NULL_TREE;
10429 tree prev_r = NULL_TREE;
10430 tree first_r = NULL_TREE;
10432 if (FUNCTION_PARAMETER_PACK_P (t))
10434 /* If there is a local specialization that isn't a
10435 parameter pack, it means that we're doing a "simple"
10436 substitution from inside tsubst_pack_expansion. Just
10437 return the local specialization (which will be a single
10439 tree spec = retrieve_local_specialization (t);
10441 && TREE_CODE (spec) == PARM_DECL
10442 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10445 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10446 the parameters in this function parameter pack. */
10447 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10448 complain, in_decl);
10449 if (TREE_CODE (expanded_types) == TREE_VEC)
10451 len = TREE_VEC_LENGTH (expanded_types);
10453 /* Zero-length parameter packs are boring. Just substitute
10456 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10461 /* All we did was update the type. Make a note of that. */
10462 type = expanded_types;
10463 expanded_types = NULL_TREE;
10467 /* Loop through all of the parameter's we'll build. When T is
10468 a function parameter pack, LEN is the number of expanded
10469 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10471 for (i = 0; i < len; ++i)
10475 if (DECL_TEMPLATE_PARM_P (t))
10476 SET_DECL_TEMPLATE_PARM_P (r);
10478 if (expanded_types)
10479 /* We're on the Ith parameter of the function parameter
10482 /* An argument of a function parameter pack is not a parameter
10484 FUNCTION_PARAMETER_PACK_P (r) = false;
10486 /* Get the Ith type. */
10487 type = TREE_VEC_ELT (expanded_types, i);
10490 /* Rename the parameter to include the index. */
10492 make_ith_pack_parameter_name (DECL_NAME (r), i);
10495 /* We're dealing with a normal parameter. */
10496 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10498 type = type_decays_to (type);
10499 TREE_TYPE (r) = type;
10500 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10502 if (DECL_INITIAL (r))
10504 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10505 DECL_INITIAL (r) = TREE_TYPE (r);
10507 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10508 complain, in_decl);
10511 DECL_CONTEXT (r) = NULL_TREE;
10513 if (!DECL_TEMPLATE_PARM_P (r))
10514 DECL_ARG_TYPE (r) = type_passed_as (type);
10516 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10517 args, complain, in_decl);
10519 /* Keep track of the first new parameter we
10520 generate. That's what will be returned to the
10525 /* Build a proper chain of parameters when substituting
10526 into a function parameter pack. */
10528 DECL_CHAIN (prev_r) = r;
10531 if (DECL_CHAIN (t))
10532 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10533 complain, DECL_CHAIN (t));
10535 /* FIRST_R contains the start of the chain we've built. */
10545 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10546 if (type == error_mark_node)
10547 RETURN (error_mark_node);
10548 TREE_TYPE (r) = type;
10549 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10551 if (DECL_C_BIT_FIELD (r))
10552 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10553 non-bit-fields DECL_INITIAL is a non-static data member
10554 initializer, which gets deferred instantiation. */
10556 = tsubst_expr (DECL_INITIAL (t), args,
10558 /*integral_constant_expression_p=*/true);
10559 else if (DECL_INITIAL (t))
10561 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10562 NSDMI in perform_member_init. Still set DECL_INITIAL
10563 so that we know there is one. */
10564 DECL_INITIAL (r) = void_zero_node;
10565 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10566 retrofit_lang_decl (r);
10567 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10569 /* We don't have to set DECL_CONTEXT here; it is set by
10570 finish_member_declaration. */
10571 DECL_CHAIN (r) = NULL_TREE;
10572 if (VOID_TYPE_P (type))
10573 error ("instantiation of %q+D as type %qT", r, type);
10575 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10576 args, complain, in_decl);
10581 /* We reach here only for member using decls. */
10582 if (DECL_DEPENDENT_P (t))
10584 r = do_class_using_decl
10585 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10586 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10588 r = error_mark_node;
10591 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10592 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10598 DECL_CHAIN (r) = NULL_TREE;
10605 tree argvec = NULL_TREE;
10606 tree gen_tmpl = NULL_TREE;
10608 tree tmpl = NULL_TREE;
10610 tree type = NULL_TREE;
10613 if (TREE_CODE (t) == TYPE_DECL
10614 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10616 /* If this is the canonical decl, we don't have to
10617 mess with instantiations, and often we can't (for
10618 typename, template type parms and such). Note that
10619 TYPE_NAME is not correct for the above test if
10620 we've copied the type for a typedef. */
10621 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10622 if (type == error_mark_node)
10623 RETURN (error_mark_node);
10624 r = TYPE_NAME (type);
10628 /* Check to see if we already have the specialization we
10631 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10633 /* T is a static data member or namespace-scope entity.
10634 We have to substitute into namespace-scope variables
10635 (even though such entities are never templates) because
10638 template <class T> void f() { extern T t; }
10640 where the entity referenced is not known until
10641 instantiation time. */
10643 ctx = DECL_CONTEXT (t);
10644 if (DECL_CLASS_SCOPE_P (t))
10646 ctx = tsubst_aggr_type (ctx, args,
10648 in_decl, /*entering_scope=*/1);
10649 /* If CTX is unchanged, then T is in fact the
10650 specialization we want. That situation occurs when
10651 referencing a static data member within in its own
10652 class. We can use pointer equality, rather than
10653 same_type_p, because DECL_CONTEXT is always
10655 if (ctx == DECL_CONTEXT (t)
10656 && (TREE_CODE (t) != TYPE_DECL
10657 /* ... unless T is a member template; in which
10658 case our caller can be willing to create a
10659 specialization of that template represented
10661 || !(DECL_TI_TEMPLATE (t)
10662 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10668 tmpl = DECL_TI_TEMPLATE (t);
10669 gen_tmpl = most_general_template (tmpl);
10670 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10671 if (argvec == error_mark_node)
10672 RETURN (error_mark_node);
10673 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10674 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10679 /* A local variable. */
10681 /* Subsequent calls to pushdecl will fill this in. */
10683 spec = retrieve_local_specialization (t);
10685 /* If we already have the specialization we need, there is
10686 nothing more to do. */
10693 /* Create a new node for the specialization we need. */
10695 if (type == NULL_TREE)
10697 if (is_typedef_decl (t))
10698 type = DECL_ORIGINAL_TYPE (t);
10700 type = TREE_TYPE (t);
10701 if (TREE_CODE (t) == VAR_DECL
10702 && VAR_HAD_UNKNOWN_BOUND (t)
10703 && type != error_mark_node)
10704 type = strip_array_domain (type);
10705 type = tsubst (type, args, complain, in_decl);
10707 if (TREE_CODE (r) == VAR_DECL)
10709 /* Even if the original location is out of scope, the
10710 newly substituted one is not. */
10711 DECL_DEAD_FOR_LOCAL (r) = 0;
10712 DECL_INITIALIZED_P (r) = 0;
10713 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10714 if (type == error_mark_node)
10715 RETURN (error_mark_node);
10716 if (TREE_CODE (type) == FUNCTION_TYPE)
10718 /* It may seem that this case cannot occur, since:
10723 declares a function, not a variable. However:
10726 template <typename T> void g() { T t; }
10727 template void g<f>();
10729 is an attempt to declare a variable with function
10731 error ("variable %qD has function type",
10732 /* R is not yet sufficiently initialized, so we
10733 just use its name. */
10735 RETURN (error_mark_node);
10737 type = complete_type (type);
10738 /* Wait until cp_finish_decl to set this again, to handle
10739 circular dependency (template/instantiate6.C). */
10740 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10741 type = check_var_type (DECL_NAME (r), type);
10743 if (DECL_HAS_VALUE_EXPR_P (t))
10745 tree ve = DECL_VALUE_EXPR (t);
10746 ve = tsubst_expr (ve, args, complain, in_decl,
10747 /*constant_expression_p=*/false);
10748 if (REFERENCE_REF_P (ve))
10750 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10751 ve = TREE_OPERAND (ve, 0);
10753 SET_DECL_VALUE_EXPR (r, ve);
10756 else if (DECL_SELF_REFERENCE_P (t))
10757 SET_DECL_SELF_REFERENCE_P (r);
10758 TREE_TYPE (r) = type;
10759 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10760 DECL_CONTEXT (r) = ctx;
10761 /* Clear out the mangled name and RTL for the instantiation. */
10762 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10763 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10764 SET_DECL_RTL (r, NULL);
10765 /* The initializer must not be expanded until it is required;
10766 see [temp.inst]. */
10767 DECL_INITIAL (r) = NULL_TREE;
10768 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10769 SET_DECL_RTL (r, NULL);
10770 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10771 if (TREE_CODE (r) == VAR_DECL)
10773 /* Possibly limit visibility based on template args. */
10774 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10775 if (DECL_VISIBILITY_SPECIFIED (t))
10777 DECL_VISIBILITY_SPECIFIED (r) = 0;
10778 DECL_ATTRIBUTES (r)
10779 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10781 determine_visibility (r);
10786 /* A static data member declaration is always marked
10787 external when it is declared in-class, even if an
10788 initializer is present. We mimic the non-template
10789 processing here. */
10790 DECL_EXTERNAL (r) = 1;
10792 register_specialization (r, gen_tmpl, argvec, false, hash);
10793 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10794 SET_DECL_IMPLICIT_INSTANTIATION (r);
10796 else if (cp_unevaluated_operand)
10798 /* We're substituting this var in a decltype outside of its
10799 scope, such as for a lambda return type. Don't add it to
10800 local_specializations, do perform auto deduction. */
10801 tree auto_node = type_uses_auto (type);
10805 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10806 /*constant_expression_p=*/false);
10807 init = resolve_nondeduced_context (init);
10808 TREE_TYPE (r) = type
10809 = do_auto_deduction (type, init, auto_node);
10813 register_local_specialization (r, t);
10815 DECL_CHAIN (r) = NULL_TREE;
10817 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10819 args, complain, in_decl);
10821 /* Preserve a typedef that names a type. */
10822 if (is_typedef_decl (r))
10824 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10825 set_underlying_type (r);
10828 layout_decl (r, 0);
10833 gcc_unreachable ();
10838 /* Restore the file and line information. */
10839 input_location = saved_loc;
10844 /* Substitute into the ARG_TYPES of a function type. */
10847 tsubst_arg_types (tree arg_types,
10849 tsubst_flags_t complain,
10852 tree remaining_arg_types;
10853 tree type = NULL_TREE;
10855 tree expanded_args = NULL_TREE;
10858 if (!arg_types || arg_types == void_list_node)
10861 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10862 args, complain, in_decl);
10863 if (remaining_arg_types == error_mark_node)
10864 return error_mark_node;
10866 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10868 /* For a pack expansion, perform substitution on the
10869 entire expression. Later on, we'll handle the arguments
10871 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10872 args, complain, in_decl);
10874 if (TREE_CODE (expanded_args) == TREE_VEC)
10875 /* So that we'll spin through the parameters, one by one. */
10876 i = TREE_VEC_LENGTH (expanded_args);
10879 /* We only partially substituted into the parameter
10880 pack. Our type is TYPE_PACK_EXPANSION. */
10881 type = expanded_args;
10882 expanded_args = NULL_TREE;
10890 type = TREE_VEC_ELT (expanded_args, i);
10892 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10894 if (type == error_mark_node)
10895 return error_mark_node;
10896 if (VOID_TYPE_P (type))
10898 if (complain & tf_error)
10900 error ("invalid parameter type %qT", type);
10902 error ("in declaration %q+D", in_decl);
10904 return error_mark_node;
10907 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10908 top-level qualifiers as required. */
10909 type = cv_unqualified (type_decays_to (type));
10911 /* We do not substitute into default arguments here. The standard
10912 mandates that they be instantiated only when needed, which is
10913 done in build_over_call. */
10914 default_arg = TREE_PURPOSE (arg_types);
10916 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10918 /* We've instantiated a template before its default arguments
10919 have been parsed. This can happen for a nested template
10920 class, and is not an error unless we require the default
10921 argument in a call of this function. */
10922 remaining_arg_types =
10923 tree_cons (default_arg, type, remaining_arg_types);
10924 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10925 remaining_arg_types);
10928 remaining_arg_types =
10929 hash_tree_cons (default_arg, type, remaining_arg_types);
10932 return remaining_arg_types;
10935 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10936 *not* handle the exception-specification for FNTYPE, because the
10937 initial substitution of explicitly provided template parameters
10938 during argument deduction forbids substitution into the
10939 exception-specification:
10943 All references in the function type of the function template to the
10944 corresponding template parameters are replaced by the specified tem-
10945 plate argument values. If a substitution in a template parameter or
10946 in the function type of the function template results in an invalid
10947 type, type deduction fails. [Note: The equivalent substitution in
10948 exception specifications is done only when the function is instanti-
10949 ated, at which point a program is ill-formed if the substitution
10950 results in an invalid type.] */
10953 tsubst_function_type (tree t,
10955 tsubst_flags_t complain,
10962 /* The TYPE_CONTEXT is not used for function/method types. */
10963 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10965 /* Substitute the return type. */
10966 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10967 if (return_type == error_mark_node)
10968 return error_mark_node;
10969 /* The standard does not presently indicate that creation of a
10970 function type with an invalid return type is a deduction failure.
10971 However, that is clearly analogous to creating an array of "void"
10972 or a reference to a reference. This is core issue #486. */
10973 if (TREE_CODE (return_type) == ARRAY_TYPE
10974 || TREE_CODE (return_type) == FUNCTION_TYPE)
10976 if (complain & tf_error)
10978 if (TREE_CODE (return_type) == ARRAY_TYPE)
10979 error ("function returning an array");
10981 error ("function returning a function");
10983 return error_mark_node;
10986 /* Substitute the argument types. */
10987 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10988 complain, in_decl);
10989 if (arg_types == error_mark_node)
10990 return error_mark_node;
10992 /* Construct a new type node and return it. */
10993 if (TREE_CODE (t) == FUNCTION_TYPE)
10995 fntype = build_function_type (return_type, arg_types);
10996 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
11000 tree r = TREE_TYPE (TREE_VALUE (arg_types));
11001 if (! MAYBE_CLASS_TYPE_P (r))
11005 Type deduction may fail for any of the following
11008 -- Attempting to create "pointer to member of T" when T
11009 is not a class type. */
11010 if (complain & tf_error)
11011 error ("creating pointer to member function of non-class type %qT",
11013 return error_mark_node;
11016 fntype = build_method_type_directly (r, return_type,
11017 TREE_CHAIN (arg_types));
11019 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
11024 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
11025 ARGS into that specification, and return the substituted
11026 specification. If there is no specification, return NULL_TREE. */
11029 tsubst_exception_specification (tree fntype,
11031 tsubst_flags_t complain,
11038 specs = TYPE_RAISES_EXCEPTIONS (fntype);
11039 new_specs = NULL_TREE;
11040 if (specs && TREE_PURPOSE (specs))
11042 /* A noexcept-specifier. */
11043 tree expr = TREE_PURPOSE (specs);
11044 if (expr == boolean_true_node || expr == boolean_false_node)
11048 /* Defer instantiation of noexcept-specifiers to avoid
11049 excessive instantiations (c++/49107). */
11050 new_specs = make_node (DEFERRED_NOEXCEPT);
11051 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
11053 /* We already partially instantiated this member template,
11054 so combine the new args with the old. */
11055 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11056 = DEFERRED_NOEXCEPT_PATTERN (expr);
11057 DEFERRED_NOEXCEPT_ARGS (new_specs)
11058 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11062 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11063 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11067 new_specs = tsubst_copy_and_build
11068 (expr, args, complain, in_decl, /*function_p=*/false,
11069 /*integral_constant_expression_p=*/true);
11070 new_specs = build_noexcept_spec (new_specs, complain);
11074 if (! TREE_VALUE (specs))
11081 tree expanded_specs = NULL_TREE;
11083 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11085 /* Expand the pack expansion type. */
11086 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11090 if (expanded_specs == error_mark_node)
11091 return error_mark_node;
11092 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11093 len = TREE_VEC_LENGTH (expanded_specs);
11096 /* We're substituting into a member template, so
11097 we got a TYPE_PACK_EXPANSION back. Add that
11098 expansion and move on. */
11099 gcc_assert (TREE_CODE (expanded_specs)
11100 == TYPE_PACK_EXPANSION);
11101 new_specs = add_exception_specifier (new_specs,
11104 specs = TREE_CHAIN (specs);
11109 for (i = 0; i < len; ++i)
11111 if (expanded_specs)
11112 spec = TREE_VEC_ELT (expanded_specs, i);
11114 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11115 if (spec == error_mark_node)
11117 new_specs = add_exception_specifier (new_specs, spec,
11121 specs = TREE_CHAIN (specs);
11127 /* Take the tree structure T and replace template parameters used
11128 therein with the argument vector ARGS. IN_DECL is an associated
11129 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11130 Issue error and warning messages under control of COMPLAIN. Note
11131 that we must be relatively non-tolerant of extensions here, in
11132 order to preserve conformance; if we allow substitutions that
11133 should not be allowed, we may allow argument deductions that should
11134 not succeed, and therefore report ambiguous overload situations
11135 where there are none. In theory, we could allow the substitution,
11136 but indicate that it should have failed, and allow our caller to
11137 make sure that the right thing happens, but we don't try to do this
11140 This function is used for dealing with types, decls and the like;
11141 for expressions, use tsubst_expr or tsubst_copy. */
11144 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11146 enum tree_code code;
11147 tree type, r = NULL_TREE;
11149 if (t == NULL_TREE || t == error_mark_node
11150 || t == integer_type_node
11151 || t == void_type_node
11152 || t == char_type_node
11153 || t == unknown_type_node
11154 || TREE_CODE (t) == NAMESPACE_DECL
11155 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11159 return tsubst_decl (t, args, complain);
11161 if (args == NULL_TREE)
11164 code = TREE_CODE (t);
11166 if (code == IDENTIFIER_NODE)
11167 type = IDENTIFIER_TYPE_VALUE (t);
11169 type = TREE_TYPE (t);
11171 gcc_assert (type != unknown_type_node);
11173 /* Reuse typedefs. We need to do this to handle dependent attributes,
11174 such as attribute aligned. */
11176 && typedef_variant_p (t))
11178 tree decl = TYPE_NAME (t);
11180 if (TYPE_DECL_ALIAS_P (decl)
11181 && DECL_LANG_SPECIFIC (decl)
11182 && DECL_TEMPLATE_INFO (decl)
11183 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11185 /* DECL represents an alias template and we want to
11186 instantiate it. Let's substitute our arguments for the
11187 template parameters into the declaration and get the
11189 r = tsubst (decl, args, complain, decl);
11191 else if (DECL_CLASS_SCOPE_P (decl)
11192 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11193 && uses_template_parms (DECL_CONTEXT (decl)))
11195 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11196 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11197 r = retrieve_specialization (tmpl, gen_args, 0);
11199 else if (DECL_FUNCTION_SCOPE_P (decl)
11200 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11201 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11202 r = retrieve_local_specialization (decl);
11204 /* The typedef is from a non-template context. */
11210 r = cp_build_qualified_type_real
11211 (r, cp_type_quals (t) | cp_type_quals (r),
11212 complain | tf_ignore_bad_quals);
11216 /* We don't have an instantiation yet, so drop the typedef. */
11217 t = DECL_ORIGINAL_TYPE (decl);
11221 && code != TYPENAME_TYPE
11222 && code != TEMPLATE_TYPE_PARM
11223 && code != IDENTIFIER_NODE
11224 && code != FUNCTION_TYPE
11225 && code != METHOD_TYPE)
11226 type = tsubst (type, args, complain, in_decl);
11227 if (type == error_mark_node)
11228 return error_mark_node;
11234 case ENUMERAL_TYPE:
11235 return tsubst_aggr_type (t, args, complain, in_decl,
11236 /*entering_scope=*/0);
11239 case IDENTIFIER_NODE:
11250 if (t == integer_type_node)
11253 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11254 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11258 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11260 max = tsubst_expr (omax, args, complain, in_decl,
11261 /*integral_constant_expression_p=*/false);
11263 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11265 if (TREE_CODE (max) == NOP_EXPR
11266 && TREE_SIDE_EFFECTS (omax)
11267 && !TREE_TYPE (max))
11268 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11270 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11271 with TREE_SIDE_EFFECTS that indicates this is not an integral
11272 constant expression. */
11273 if (processing_template_decl
11274 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11276 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11277 TREE_SIDE_EFFECTS (max) = 1;
11280 return compute_array_index_type (NULL_TREE, max, complain);
11283 case TEMPLATE_TYPE_PARM:
11284 case TEMPLATE_TEMPLATE_PARM:
11285 case BOUND_TEMPLATE_TEMPLATE_PARM:
11286 case TEMPLATE_PARM_INDEX:
11291 tree arg = NULL_TREE;
11295 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11296 template_parm_level_and_index (t, &level, &idx);
11298 levels = TMPL_ARGS_DEPTH (args);
11299 if (level <= levels)
11301 arg = TMPL_ARG (args, level, idx);
11303 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11304 /* See through ARGUMENT_PACK_SELECT arguments. */
11305 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11308 if (arg == error_mark_node)
11309 return error_mark_node;
11310 else if (arg != NULL_TREE)
11312 if (ARGUMENT_PACK_P (arg))
11313 /* If ARG is an argument pack, we don't actually want to
11314 perform a substitution here, because substitutions
11315 for argument packs are only done
11316 element-by-element. We can get to this point when
11317 substituting the type of a non-type template
11318 parameter pack, when that type actually contains
11319 template parameter packs from an outer template, e.g.,
11321 template<typename... Types> struct A {
11322 template<Types... Values> struct B { };
11326 if (code == TEMPLATE_TYPE_PARM)
11329 gcc_assert (TYPE_P (arg));
11331 quals = cp_type_quals (arg) | cp_type_quals (t);
11333 return cp_build_qualified_type_real
11334 (arg, quals, complain | tf_ignore_bad_quals);
11336 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11338 /* We are processing a type constructed from a
11339 template template parameter. */
11340 tree argvec = tsubst (TYPE_TI_ARGS (t),
11341 args, complain, in_decl);
11342 if (argvec == error_mark_node)
11343 return error_mark_node;
11345 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11346 || TREE_CODE (arg) == TEMPLATE_DECL
11347 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11349 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11350 /* Consider this code:
11352 template <template <class> class Template>
11354 template <class Arg> using Bind = Template<Arg>;
11357 template <template <class> class Template, class Arg>
11358 using Instantiate = Template<Arg>; //#0
11360 template <template <class> class Template,
11363 Instantiate<Internal<Template>::template Bind,
11366 When #1 is parsed, the
11367 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11368 parameter `Template' in #0 matches the
11369 UNBOUND_CLASS_TEMPLATE representing the argument
11370 `Internal<Template>::template Bind'; We then want
11371 to assemble the type `Bind<Argument>' that can't
11372 be fully created right now, because
11373 `Internal<Template>' not being complete, the Bind
11374 template cannot be looked up in that context. So
11375 we need to "store" `Bind<Argument>' for later
11376 when the context of Bind becomes complete. Let's
11377 store that in a TYPENAME_TYPE. */
11378 return make_typename_type (TYPE_CONTEXT (arg),
11379 build_nt (TEMPLATE_ID_EXPR,
11380 TYPE_IDENTIFIER (arg),
11385 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11386 are resolving nested-types in the signature of a
11387 member function templates. Otherwise ARG is a
11388 TEMPLATE_DECL and is the real template to be
11390 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11391 arg = TYPE_NAME (arg);
11393 r = lookup_template_class (arg,
11395 DECL_CONTEXT (arg),
11396 /*entering_scope=*/0,
11398 return cp_build_qualified_type_real
11399 (r, cp_type_quals (t), complain);
11402 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11403 return convert_from_reference (unshare_expr (arg));
11407 /* This can happen during the attempted tsubst'ing in
11408 unify. This means that we don't yet have any information
11409 about the template parameter in question. */
11412 /* If we get here, we must have been looking at a parm for a
11413 more deeply nested template. Make a new version of this
11414 template parameter, but with a lower level. */
11417 case TEMPLATE_TYPE_PARM:
11418 case TEMPLATE_TEMPLATE_PARM:
11419 case BOUND_TEMPLATE_TEMPLATE_PARM:
11420 if (cp_type_quals (t))
11422 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11423 r = cp_build_qualified_type_real
11424 (r, cp_type_quals (t),
11425 complain | (code == TEMPLATE_TYPE_PARM
11426 ? tf_ignore_bad_quals : 0));
11431 TEMPLATE_TYPE_PARM_INDEX (r)
11432 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11433 r, levels, args, complain);
11434 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11435 TYPE_MAIN_VARIANT (r) = r;
11436 TYPE_POINTER_TO (r) = NULL_TREE;
11437 TYPE_REFERENCE_TO (r) = NULL_TREE;
11439 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11440 /* We have reduced the level of the template
11441 template parameter, but not the levels of its
11442 template parameters, so canonical_type_parameter
11443 will not be able to find the canonical template
11444 template parameter for this level. Thus, we
11445 require structural equality checking to compare
11446 TEMPLATE_TEMPLATE_PARMs. */
11447 SET_TYPE_STRUCTURAL_EQUALITY (r);
11448 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11449 SET_TYPE_STRUCTURAL_EQUALITY (r);
11451 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11453 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11455 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11456 complain, in_decl);
11457 if (argvec == error_mark_node)
11458 return error_mark_node;
11460 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11461 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11466 case TEMPLATE_PARM_INDEX:
11467 r = reduce_template_parm_level (t, type, levels, args, complain);
11471 gcc_unreachable ();
11479 tree purpose, value, chain;
11481 if (t == void_list_node)
11484 purpose = TREE_PURPOSE (t);
11487 purpose = tsubst (purpose, args, complain, in_decl);
11488 if (purpose == error_mark_node)
11489 return error_mark_node;
11491 value = TREE_VALUE (t);
11494 value = tsubst (value, args, complain, in_decl);
11495 if (value == error_mark_node)
11496 return error_mark_node;
11498 chain = TREE_CHAIN (t);
11499 if (chain && chain != void_type_node)
11501 chain = tsubst (chain, args, complain, in_decl);
11502 if (chain == error_mark_node)
11503 return error_mark_node;
11505 if (purpose == TREE_PURPOSE (t)
11506 && value == TREE_VALUE (t)
11507 && chain == TREE_CHAIN (t))
11509 return hash_tree_cons (purpose, value, chain);
11513 /* We should never be tsubsting a binfo. */
11514 gcc_unreachable ();
11517 /* A vector of template arguments. */
11518 gcc_assert (!type);
11519 return tsubst_template_args (t, args, complain, in_decl);
11522 case REFERENCE_TYPE:
11524 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11529 Type deduction may fail for any of the following
11532 -- Attempting to create a pointer to reference type.
11533 -- Attempting to create a reference to a reference type or
11534 a reference to void.
11536 Core issue 106 says that creating a reference to a reference
11537 during instantiation is no longer a cause for failure. We
11538 only enforce this check in strict C++98 mode. */
11539 if ((TREE_CODE (type) == REFERENCE_TYPE
11540 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11541 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11543 static location_t last_loc;
11545 /* We keep track of the last time we issued this error
11546 message to avoid spewing a ton of messages during a
11547 single bad template instantiation. */
11548 if (complain & tf_error
11549 && last_loc != input_location)
11551 if (TREE_CODE (type) == VOID_TYPE)
11552 error ("forming reference to void");
11553 else if (code == POINTER_TYPE)
11554 error ("forming pointer to reference type %qT", type);
11556 error ("forming reference to reference type %qT", type);
11557 last_loc = input_location;
11560 return error_mark_node;
11562 else if (code == POINTER_TYPE)
11564 r = build_pointer_type (type);
11565 if (TREE_CODE (type) == METHOD_TYPE)
11566 r = build_ptrmemfunc_type (r);
11568 else if (TREE_CODE (type) == REFERENCE_TYPE)
11569 /* In C++0x, during template argument substitution, when there is an
11570 attempt to create a reference to a reference type, reference
11571 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11573 "If a template-argument for a template-parameter T names a type
11574 that is a reference to a type A, an attempt to create the type
11575 'lvalue reference to cv T' creates the type 'lvalue reference to
11576 A,' while an attempt to create the type type rvalue reference to
11577 cv T' creates the type T"
11579 r = cp_build_reference_type
11581 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11583 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11584 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11586 if (r != error_mark_node)
11587 /* Will this ever be needed for TYPE_..._TO values? */
11594 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11595 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11599 Type deduction may fail for any of the following
11602 -- Attempting to create "pointer to member of T" when T
11603 is not a class type. */
11604 if (complain & tf_error)
11605 error ("creating pointer to member of non-class type %qT", r);
11606 return error_mark_node;
11608 if (TREE_CODE (type) == REFERENCE_TYPE)
11610 if (complain & tf_error)
11611 error ("creating pointer to member reference type %qT", type);
11612 return error_mark_node;
11614 if (TREE_CODE (type) == VOID_TYPE)
11616 if (complain & tf_error)
11617 error ("creating pointer to member of type void");
11618 return error_mark_node;
11620 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11621 if (TREE_CODE (type) == FUNCTION_TYPE)
11623 /* The type of the implicit object parameter gets its
11624 cv-qualifiers from the FUNCTION_TYPE. */
11626 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11627 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11628 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11632 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11636 case FUNCTION_TYPE:
11641 fntype = tsubst_function_type (t, args, complain, in_decl);
11642 if (fntype == error_mark_node)
11643 return error_mark_node;
11645 /* Substitute the exception specification. */
11646 specs = tsubst_exception_specification (t, args, complain,
11647 in_decl, /*defer_ok*/true);
11648 if (specs == error_mark_node)
11649 return error_mark_node;
11651 fntype = build_exception_variant (fntype, specs);
11656 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11657 if (domain == error_mark_node)
11658 return error_mark_node;
11660 /* As an optimization, we avoid regenerating the array type if
11661 it will obviously be the same as T. */
11662 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11665 /* These checks should match the ones in grokdeclarator.
11669 The deduction may fail for any of the following reasons:
11671 -- Attempting to create an array with an element type that
11672 is void, a function type, or a reference type, or [DR337]
11673 an abstract class type. */
11674 if (TREE_CODE (type) == VOID_TYPE
11675 || TREE_CODE (type) == FUNCTION_TYPE
11676 || TREE_CODE (type) == REFERENCE_TYPE)
11678 if (complain & tf_error)
11679 error ("creating array of %qT", type);
11680 return error_mark_node;
11682 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11684 if (complain & tf_error)
11685 error ("creating array of %qT, which is an abstract class type",
11687 return error_mark_node;
11690 r = build_cplus_array_type (type, domain);
11692 if (TYPE_USER_ALIGN (t))
11694 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11695 TYPE_USER_ALIGN (r) = 1;
11701 case TYPENAME_TYPE:
11703 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11704 in_decl, /*entering_scope=*/1);
11705 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11706 complain, in_decl);
11708 if (ctx == error_mark_node || f == error_mark_node)
11709 return error_mark_node;
11711 if (!MAYBE_CLASS_TYPE_P (ctx))
11713 if (complain & tf_error)
11714 error ("%qT is not a class, struct, or union type", ctx);
11715 return error_mark_node;
11717 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11719 /* Normally, make_typename_type does not require that the CTX
11720 have complete type in order to allow things like:
11722 template <class T> struct S { typename S<T>::X Y; };
11724 But, such constructs have already been resolved by this
11725 point, so here CTX really should have complete type, unless
11726 it's a partial instantiation. */
11727 ctx = complete_type (ctx);
11728 if (!COMPLETE_TYPE_P (ctx))
11730 if (complain & tf_error)
11731 cxx_incomplete_type_error (NULL_TREE, ctx);
11732 return error_mark_node;
11736 f = make_typename_type (ctx, f, typename_type,
11737 (complain & tf_error) | tf_keep_type_decl);
11738 if (f == error_mark_node)
11740 if (TREE_CODE (f) == TYPE_DECL)
11742 complain |= tf_ignore_bad_quals;
11746 if (TREE_CODE (f) != TYPENAME_TYPE)
11748 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11750 if (complain & tf_error)
11751 error ("%qT resolves to %qT, which is not an enumeration type",
11754 return error_mark_node;
11756 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11758 if (complain & tf_error)
11759 error ("%qT resolves to %qT, which is is not a class type",
11762 return error_mark_node;
11766 return cp_build_qualified_type_real
11767 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11770 case UNBOUND_CLASS_TEMPLATE:
11772 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11773 in_decl, /*entering_scope=*/1);
11774 tree name = TYPE_IDENTIFIER (t);
11775 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11777 if (ctx == error_mark_node || name == error_mark_node)
11778 return error_mark_node;
11781 parm_list = tsubst_template_parms (parm_list, args, complain);
11782 return make_unbound_class_template (ctx, name, parm_list, complain);
11789 ++cp_unevaluated_operand;
11790 ++c_inhibit_evaluation_warnings;
11792 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11794 /*integral_constant_expression_p=*/false);
11796 --cp_unevaluated_operand;
11797 --c_inhibit_evaluation_warnings;
11799 type = finish_typeof (type);
11800 return cp_build_qualified_type_real (type,
11802 | cp_type_quals (type),
11806 case DECLTYPE_TYPE:
11810 ++cp_unevaluated_operand;
11811 ++c_inhibit_evaluation_warnings;
11813 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11815 /*integral_constant_expression_p=*/false);
11817 --cp_unevaluated_operand;
11818 --c_inhibit_evaluation_warnings;
11820 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11821 type = lambda_capture_field_type (type);
11822 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11823 type = lambda_proxy_type (type);
11825 type = finish_decltype_type
11826 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11827 return cp_build_qualified_type_real (type,
11829 | cp_type_quals (type),
11833 case UNDERLYING_TYPE:
11835 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11836 complain, in_decl);
11837 return finish_underlying_type (type);
11840 case TYPE_ARGUMENT_PACK:
11841 case NONTYPE_ARGUMENT_PACK:
11843 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11845 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11849 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11851 /* For template nontype argument packs, also substitute into
11853 if (code == NONTYPE_ARGUMENT_PACK)
11854 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11872 /* We should use one of the expression tsubsts for these codes. */
11873 gcc_unreachable ();
11876 sorry ("use of %qs in template", tree_code_name [(int) code]);
11877 return error_mark_node;
11881 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11882 type of the expression on the left-hand side of the "." or "->"
11886 tsubst_baselink (tree baselink, tree object_type,
11887 tree args, tsubst_flags_t complain, tree in_decl)
11890 tree qualifying_scope;
11893 tree template_args = 0;
11894 bool template_id_p = false;
11895 bool qualified = BASELINK_QUALIFIED_P (baselink);
11897 /* A baselink indicates a function from a base class. Both the
11898 BASELINK_ACCESS_BINFO and the base class referenced may
11899 indicate bases of the template class, rather than the
11900 instantiated class. In addition, lookups that were not
11901 ambiguous before may be ambiguous now. Therefore, we perform
11902 the lookup again. */
11903 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11904 qualifying_scope = tsubst (qualifying_scope, args,
11905 complain, in_decl);
11906 fns = BASELINK_FUNCTIONS (baselink);
11907 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11908 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11910 template_id_p = true;
11911 template_args = TREE_OPERAND (fns, 1);
11912 fns = TREE_OPERAND (fns, 0);
11914 template_args = tsubst_template_args (template_args, args,
11915 complain, in_decl);
11917 name = DECL_NAME (get_first_fn (fns));
11918 if (IDENTIFIER_TYPENAME_P (name))
11919 name = mangle_conv_op_name_for_type (optype);
11920 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11922 return error_mark_node;
11924 /* If lookup found a single function, mark it as used at this
11925 point. (If it lookup found multiple functions the one selected
11926 later by overload resolution will be marked as used at that
11928 if (BASELINK_P (baselink))
11929 fns = BASELINK_FUNCTIONS (baselink);
11930 if (!template_id_p && !really_overloaded_fn (fns))
11931 mark_used (OVL_CURRENT (fns));
11933 /* Add back the template arguments, if present. */
11934 if (BASELINK_P (baselink) && template_id_p)
11935 BASELINK_FUNCTIONS (baselink)
11936 = build_nt (TEMPLATE_ID_EXPR,
11937 BASELINK_FUNCTIONS (baselink),
11939 /* Update the conversion operator type. */
11940 BASELINK_OPTYPE (baselink) = optype;
11943 object_type = current_class_type;
11946 baselink = adjust_result_of_qualified_name_lookup (baselink,
11952 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11953 true if the qualified-id will be a postfix-expression in-and-of
11954 itself; false if more of the postfix-expression follows the
11955 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11959 tsubst_qualified_id (tree qualified_id, tree args,
11960 tsubst_flags_t complain, tree in_decl,
11961 bool done, bool address_p)
11967 tree template_args;
11969 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11971 /* Figure out what name to look up. */
11972 name = TREE_OPERAND (qualified_id, 1);
11973 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11975 is_template = true;
11976 template_args = TREE_OPERAND (name, 1);
11978 template_args = tsubst_template_args (template_args, args,
11979 complain, in_decl);
11980 name = TREE_OPERAND (name, 0);
11984 is_template = false;
11985 template_args = NULL_TREE;
11988 /* Substitute into the qualifying scope. When there are no ARGS, we
11989 are just trying to simplify a non-dependent expression. In that
11990 case the qualifying scope may be dependent, and, in any case,
11991 substituting will not help. */
11992 scope = TREE_OPERAND (qualified_id, 0);
11995 scope = tsubst (scope, args, complain, in_decl);
11996 expr = tsubst_copy (name, args, complain, in_decl);
12001 if (dependent_scope_p (scope))
12004 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
12005 return build_qualified_name (NULL_TREE, scope, expr,
12006 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
12009 if (!BASELINK_P (name) && !DECL_P (expr))
12011 if (TREE_CODE (expr) == BIT_NOT_EXPR)
12013 /* A BIT_NOT_EXPR is used to represent a destructor. */
12014 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
12016 error ("qualifying type %qT does not match destructor name ~%qT",
12017 scope, TREE_OPERAND (expr, 0));
12018 expr = error_mark_node;
12021 expr = lookup_qualified_name (scope, complete_dtor_identifier,
12022 /*is_type_p=*/0, false);
12025 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
12026 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
12027 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
12029 if (complain & tf_error)
12031 error ("dependent-name %qE is parsed as a non-type, but "
12032 "instantiation yields a type", qualified_id);
12033 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
12035 return error_mark_node;
12041 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
12043 /* Remember that there was a reference to this entity. */
12047 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
12049 if (complain & tf_error)
12050 qualified_name_lookup_error (scope,
12051 TREE_OPERAND (qualified_id, 1),
12052 expr, input_location);
12053 return error_mark_node;
12057 expr = lookup_template_function (expr, template_args);
12059 if (expr == error_mark_node && complain & tf_error)
12060 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12061 expr, input_location);
12062 else if (TYPE_P (scope))
12064 expr = (adjust_result_of_qualified_name_lookup
12065 (expr, scope, current_class_type));
12066 expr = (finish_qualified_id_expr
12067 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12068 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12069 /*template_arg_p=*/false));
12072 /* Expressions do not generally have reference type. */
12073 if (TREE_CODE (expr) != SCOPE_REF
12074 /* However, if we're about to form a pointer-to-member, we just
12075 want the referenced member referenced. */
12076 && TREE_CODE (expr) != OFFSET_REF)
12077 expr = convert_from_reference (expr);
12082 /* Like tsubst, but deals with expressions. This function just replaces
12083 template parms; to finish processing the resultant expression, use
12084 tsubst_copy_and_build or tsubst_expr. */
12087 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12089 enum tree_code code;
12092 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12095 code = TREE_CODE (t);
12100 r = retrieve_local_specialization (t);
12106 /* We get here for a use of 'this' in an NSDMI. */
12107 if (DECL_NAME (t) == this_identifier
12108 && at_function_scope_p ()
12109 && DECL_CONSTRUCTOR_P (current_function_decl))
12110 return current_class_ptr;
12112 /* This can happen for a parameter name used later in a function
12113 declaration (such as in a late-specified return type). Just
12114 make a dummy decl, since it's only used for its type. */
12115 gcc_assert (cp_unevaluated_operand != 0);
12116 /* We copy T because want to tsubst the PARM_DECL only,
12117 not the following PARM_DECLs that are chained to T. */
12119 r = tsubst_decl (c, args, complain);
12120 /* Give it the template pattern as its context; its true context
12121 hasn't been instantiated yet and this is good enough for
12123 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12126 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12127 r = ARGUMENT_PACK_SELECT_ARG (r);
12136 if (DECL_TEMPLATE_PARM_P (t))
12137 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12138 /* There is no need to substitute into namespace-scope
12140 if (DECL_NAMESPACE_SCOPE_P (t))
12142 /* If ARGS is NULL, then T is known to be non-dependent. */
12143 if (args == NULL_TREE)
12144 return integral_constant_value (t);
12146 /* Unfortunately, we cannot just call lookup_name here.
12149 template <int I> int f() {
12151 struct S { void g() { E e = a; } };
12154 When we instantiate f<7>::S::g(), say, lookup_name is not
12155 clever enough to find f<7>::a. */
12157 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12158 /*entering_scope=*/0);
12160 for (v = TYPE_VALUES (enum_type);
12162 v = TREE_CHAIN (v))
12163 if (TREE_PURPOSE (v) == DECL_NAME (t))
12164 return TREE_VALUE (v);
12166 /* We didn't find the name. That should never happen; if
12167 name-lookup found it during preliminary parsing, we
12168 should find it again here during instantiation. */
12169 gcc_unreachable ();
12174 if (DECL_CONTEXT (t))
12178 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12179 /*entering_scope=*/1);
12180 if (ctx != DECL_CONTEXT (t))
12182 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12185 if (complain & tf_error)
12186 error ("using invalid field %qD", t);
12187 return error_mark_node;
12196 case FUNCTION_DECL:
12197 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12198 || local_variable_p (t))
12199 t = tsubst (t, args, complain, in_decl);
12203 case NAMESPACE_DECL:
12207 /* An OVERLOAD will always be a non-dependent overload set; an
12208 overload set from function scope will just be represented with an
12209 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12210 gcc_assert (!uses_template_parms (t));
12214 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12216 case TEMPLATE_DECL:
12217 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12218 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12219 args, complain, in_decl);
12220 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12221 return tsubst (t, args, complain, in_decl);
12222 else if (DECL_CLASS_SCOPE_P (t)
12223 && uses_template_parms (DECL_CONTEXT (t)))
12225 /* Template template argument like the following example need
12228 template <template <class> class TT> struct C {};
12229 template <class T> struct D {
12230 template <class U> struct E {};
12235 We are processing the template argument `E' in #1 for
12236 the template instantiation #2. Originally, `E' is a
12237 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12238 have to substitute this with one having context `D<int>'. */
12240 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12241 return lookup_field (context, DECL_NAME(t), 0, false);
12244 /* Ordinary template template argument. */
12248 case REINTERPRET_CAST_EXPR:
12249 case CONST_CAST_EXPR:
12250 case STATIC_CAST_EXPR:
12251 case DYNAMIC_CAST_EXPR:
12252 case IMPLICIT_CONV_EXPR:
12256 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12257 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12260 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12266 ++cp_unevaluated_operand;
12267 ++c_inhibit_evaluation_warnings;
12268 /* We only want to compute the number of arguments. */
12269 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12270 complain, in_decl);
12271 --cp_unevaluated_operand;
12272 --c_inhibit_evaluation_warnings;
12274 if (TREE_CODE (expanded) == TREE_VEC)
12275 len = TREE_VEC_LENGTH (expanded);
12277 if (expanded == error_mark_node)
12278 return error_mark_node;
12279 else if (PACK_EXPANSION_P (expanded)
12280 || (TREE_CODE (expanded) == TREE_VEC
12282 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12284 if (TREE_CODE (expanded) == TREE_VEC)
12285 expanded = TREE_VEC_ELT (expanded, len - 1);
12287 if (TYPE_P (expanded))
12288 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12289 complain & tf_error);
12291 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12292 complain & tf_error);
12295 return build_int_cst (size_type_node, len);
12301 case TRUTH_NOT_EXPR:
12304 case UNARY_PLUS_EXPR: /* Unary + */
12306 case AT_ENCODE_EXPR:
12310 case REALPART_EXPR:
12311 case IMAGPART_EXPR:
12313 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12314 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12316 case COMPONENT_REF:
12321 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12322 name = TREE_OPERAND (t, 1);
12323 if (TREE_CODE (name) == BIT_NOT_EXPR)
12325 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12326 complain, in_decl);
12327 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12329 else if (TREE_CODE (name) == SCOPE_REF
12330 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12332 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12333 complain, in_decl);
12334 name = TREE_OPERAND (name, 1);
12335 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12336 complain, in_decl);
12337 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12338 name = build_qualified_name (/*type=*/NULL_TREE,
12340 /*template_p=*/false);
12342 else if (BASELINK_P (name))
12343 name = tsubst_baselink (name,
12344 non_reference (TREE_TYPE (object)),
12348 name = tsubst_copy (name, args, complain, in_decl);
12349 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12355 case TRUNC_DIV_EXPR:
12356 case CEIL_DIV_EXPR:
12357 case FLOOR_DIV_EXPR:
12358 case ROUND_DIV_EXPR:
12359 case EXACT_DIV_EXPR:
12363 case TRUNC_MOD_EXPR:
12364 case FLOOR_MOD_EXPR:
12365 case TRUTH_ANDIF_EXPR:
12366 case TRUTH_ORIF_EXPR:
12367 case TRUTH_AND_EXPR:
12368 case TRUTH_OR_EXPR:
12381 case COMPOUND_EXPR:
12384 case PREDECREMENT_EXPR:
12385 case PREINCREMENT_EXPR:
12386 case POSTDECREMENT_EXPR:
12387 case POSTINCREMENT_EXPR:
12389 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12390 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12393 return build_qualified_name (/*type=*/NULL_TREE,
12394 tsubst_copy (TREE_OPERAND (t, 0),
12395 args, complain, in_decl),
12396 tsubst_copy (TREE_OPERAND (t, 1),
12397 args, complain, in_decl),
12398 QUALIFIED_NAME_IS_TEMPLATE (t));
12403 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12404 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12405 NULL_TREE, NULL_TREE);
12409 int n = VL_EXP_OPERAND_LENGTH (t);
12410 tree result = build_vl_exp (CALL_EXPR, n);
12412 for (i = 0; i < n; i++)
12413 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12414 complain, in_decl);
12420 case PSEUDO_DTOR_EXPR:
12423 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12424 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12425 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12426 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12433 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12434 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12435 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12436 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12443 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12444 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12445 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12446 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12450 case TEMPLATE_ID_EXPR:
12452 /* Substituted template arguments */
12453 tree fn = TREE_OPERAND (t, 0);
12454 tree targs = TREE_OPERAND (t, 1);
12456 fn = tsubst_copy (fn, args, complain, in_decl);
12458 targs = tsubst_template_args (targs, args, complain, in_decl);
12460 return lookup_template_function (fn, targs);
12465 tree purpose, value, chain;
12467 if (t == void_list_node)
12470 purpose = TREE_PURPOSE (t);
12472 purpose = tsubst_copy (purpose, args, complain, in_decl);
12473 value = TREE_VALUE (t);
12475 value = tsubst_copy (value, args, complain, in_decl);
12476 chain = TREE_CHAIN (t);
12477 if (chain && chain != void_type_node)
12478 chain = tsubst_copy (chain, args, complain, in_decl);
12479 if (purpose == TREE_PURPOSE (t)
12480 && value == TREE_VALUE (t)
12481 && chain == TREE_CHAIN (t))
12483 return tree_cons (purpose, value, chain);
12488 case ENUMERAL_TYPE:
12490 case TEMPLATE_TYPE_PARM:
12491 case TEMPLATE_TEMPLATE_PARM:
12492 case BOUND_TEMPLATE_TEMPLATE_PARM:
12493 case TEMPLATE_PARM_INDEX:
12495 case REFERENCE_TYPE:
12497 case FUNCTION_TYPE:
12500 case TYPENAME_TYPE:
12501 case UNBOUND_CLASS_TEMPLATE:
12503 case DECLTYPE_TYPE:
12505 return tsubst (t, args, complain, in_decl);
12507 case IDENTIFIER_NODE:
12508 if (IDENTIFIER_TYPENAME_P (t))
12510 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12511 return mangle_conv_op_name_for_type (new_type);
12517 /* This is handled by tsubst_copy_and_build. */
12518 gcc_unreachable ();
12521 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12523 tsubst (TREE_TYPE (t), args, complain, in_decl));
12525 case CLEANUP_POINT_EXPR:
12526 /* We shouldn't have built any of these during initial template
12527 generation. Instead, they should be built during instantiation
12528 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12529 gcc_unreachable ();
12533 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12534 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12535 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12536 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12537 mark_used (TREE_OPERAND (r, 1));
12540 case EXPR_PACK_EXPANSION:
12541 error ("invalid use of pack expansion expression");
12542 return error_mark_node;
12544 case NONTYPE_ARGUMENT_PACK:
12545 error ("use %<...%> to expand argument pack");
12546 return error_mark_node;
12553 /* Instantiate any typedefs in the type. */
12554 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12555 r = fold_convert (type, t);
12556 gcc_assert (TREE_CODE (r) == code);
12561 /* These can sometimes show up in a partial instantiation, but never
12562 involve template parms. */
12563 gcc_assert (!uses_template_parms (t));
12567 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12568 gcc_checking_assert (false);
12573 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12576 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12579 tree new_clauses = NULL, nc, oc;
12581 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12583 nc = copy_node (oc);
12584 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12587 switch (OMP_CLAUSE_CODE (nc))
12589 case OMP_CLAUSE_LASTPRIVATE:
12590 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12592 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12593 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12594 in_decl, /*integral_constant_expression_p=*/false);
12595 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12596 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12599 case OMP_CLAUSE_PRIVATE:
12600 case OMP_CLAUSE_SHARED:
12601 case OMP_CLAUSE_FIRSTPRIVATE:
12602 case OMP_CLAUSE_REDUCTION:
12603 case OMP_CLAUSE_COPYIN:
12604 case OMP_CLAUSE_COPYPRIVATE:
12605 case OMP_CLAUSE_IF:
12606 case OMP_CLAUSE_NUM_THREADS:
12607 case OMP_CLAUSE_SCHEDULE:
12608 case OMP_CLAUSE_COLLAPSE:
12609 case OMP_CLAUSE_FINAL:
12610 OMP_CLAUSE_OPERAND (nc, 0)
12611 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12612 in_decl, /*integral_constant_expression_p=*/false);
12614 case OMP_CLAUSE_NOWAIT:
12615 case OMP_CLAUSE_ORDERED:
12616 case OMP_CLAUSE_DEFAULT:
12617 case OMP_CLAUSE_UNTIED:
12618 case OMP_CLAUSE_MERGEABLE:
12621 gcc_unreachable ();
12625 return finish_omp_clauses (nreverse (new_clauses));
12628 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12631 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12634 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12636 tree purpose, value, chain;
12641 if (TREE_CODE (t) != TREE_LIST)
12642 return tsubst_copy_and_build (t, args, complain, in_decl,
12643 /*function_p=*/false,
12644 /*integral_constant_expression_p=*/false);
12646 if (t == void_list_node)
12649 purpose = TREE_PURPOSE (t);
12651 purpose = RECUR (purpose);
12652 value = TREE_VALUE (t);
12655 if (TREE_CODE (value) != LABEL_DECL)
12656 value = RECUR (value);
12659 value = lookup_label (DECL_NAME (value));
12660 gcc_assert (TREE_CODE (value) == LABEL_DECL);
12661 TREE_USED (value) = 1;
12664 chain = TREE_CHAIN (t);
12665 if (chain && chain != void_type_node)
12666 chain = RECUR (chain);
12667 return tree_cons (purpose, value, chain);
12671 /* Substitute one OMP_FOR iterator. */
12674 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12675 tree condv, tree incrv, tree *clauses,
12676 tree args, tsubst_flags_t complain, tree in_decl,
12677 bool integral_constant_expression_p)
12679 #define RECUR(NODE) \
12680 tsubst_expr ((NODE), args, complain, in_decl, \
12681 integral_constant_expression_p)
12682 tree decl, init, cond, incr, auto_node;
12684 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12685 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12686 decl = RECUR (TREE_OPERAND (init, 0));
12687 init = TREE_OPERAND (init, 1);
12688 auto_node = type_uses_auto (TREE_TYPE (decl));
12689 if (auto_node && init)
12691 tree init_expr = init;
12692 if (TREE_CODE (init_expr) == DECL_EXPR)
12693 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12694 init_expr = RECUR (init_expr);
12696 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12698 gcc_assert (!type_dependent_expression_p (decl));
12700 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12702 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12703 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12704 if (TREE_CODE (incr) == MODIFY_EXPR)
12705 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12706 RECUR (TREE_OPERAND (incr, 1)),
12709 incr = RECUR (incr);
12710 TREE_VEC_ELT (declv, i) = decl;
12711 TREE_VEC_ELT (initv, i) = init;
12712 TREE_VEC_ELT (condv, i) = cond;
12713 TREE_VEC_ELT (incrv, i) = incr;
12717 if (init && TREE_CODE (init) != DECL_EXPR)
12720 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12722 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12723 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12724 && OMP_CLAUSE_DECL (c) == decl)
12726 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12727 && OMP_CLAUSE_DECL (c) == decl)
12728 error ("iteration variable %qD should not be firstprivate", decl);
12729 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12730 && OMP_CLAUSE_DECL (c) == decl)
12731 error ("iteration variable %qD should not be reduction", decl);
12735 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12736 OMP_CLAUSE_DECL (c) = decl;
12737 c = finish_omp_clauses (c);
12740 OMP_CLAUSE_CHAIN (c) = *clauses;
12745 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12746 if (COMPARISON_CLASS_P (cond))
12747 cond = build2 (TREE_CODE (cond), boolean_type_node,
12748 RECUR (TREE_OPERAND (cond, 0)),
12749 RECUR (TREE_OPERAND (cond, 1)));
12751 cond = RECUR (cond);
12752 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12753 switch (TREE_CODE (incr))
12755 case PREINCREMENT_EXPR:
12756 case PREDECREMENT_EXPR:
12757 case POSTINCREMENT_EXPR:
12758 case POSTDECREMENT_EXPR:
12759 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12760 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12763 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12764 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12766 tree rhs = TREE_OPERAND (incr, 1);
12767 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12768 RECUR (TREE_OPERAND (incr, 0)),
12769 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12770 RECUR (TREE_OPERAND (rhs, 0)),
12771 RECUR (TREE_OPERAND (rhs, 1))));
12774 incr = RECUR (incr);
12777 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12778 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12780 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12781 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12782 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12783 TREE_TYPE (decl), lhs,
12784 RECUR (TREE_OPERAND (incr, 2))));
12786 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12787 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12788 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12790 tree rhs = TREE_OPERAND (incr, 2);
12791 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12792 RECUR (TREE_OPERAND (incr, 0)),
12793 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12794 RECUR (TREE_OPERAND (rhs, 0)),
12795 RECUR (TREE_OPERAND (rhs, 1))));
12798 incr = RECUR (incr);
12801 incr = RECUR (incr);
12805 TREE_VEC_ELT (declv, i) = decl;
12806 TREE_VEC_ELT (initv, i) = init;
12807 TREE_VEC_ELT (condv, i) = cond;
12808 TREE_VEC_ELT (incrv, i) = incr;
12812 /* Like tsubst_copy for expressions, etc. but also does semantic
12816 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12817 bool integral_constant_expression_p)
12819 #define RECUR(NODE) \
12820 tsubst_expr ((NODE), args, complain, in_decl, \
12821 integral_constant_expression_p)
12825 if (t == NULL_TREE || t == error_mark_node)
12828 if (EXPR_HAS_LOCATION (t))
12829 input_location = EXPR_LOCATION (t);
12830 if (STATEMENT_CODE_P (TREE_CODE (t)))
12831 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12833 switch (TREE_CODE (t))
12835 case STATEMENT_LIST:
12837 tree_stmt_iterator i;
12838 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12839 RECUR (tsi_stmt (i));
12843 case CTOR_INITIALIZER:
12844 finish_mem_initializers (tsubst_initializer_list
12845 (TREE_OPERAND (t, 0), args));
12849 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12853 tmp = RECUR (EXPR_STMT_EXPR (t));
12854 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12855 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12857 finish_expr_stmt (tmp);
12861 do_using_directive (USING_STMT_NAMESPACE (t));
12866 tree decl, pattern_decl;
12869 pattern_decl = decl = DECL_EXPR_DECL (t);
12870 if (TREE_CODE (decl) == LABEL_DECL)
12871 finish_label_decl (DECL_NAME (decl));
12872 else if (TREE_CODE (decl) == USING_DECL)
12874 tree scope = USING_DECL_SCOPE (decl);
12875 tree name = DECL_NAME (decl);
12878 scope = tsubst (scope, args, complain, in_decl);
12879 decl = lookup_qualified_name (scope, name,
12880 /*is_type_p=*/false,
12881 /*complain=*/false);
12882 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12883 qualified_name_lookup_error (scope, name, decl, input_location);
12885 do_local_using_decl (decl, scope, name);
12889 init = DECL_INITIAL (decl);
12890 decl = tsubst (decl, args, complain, in_decl);
12891 if (decl != error_mark_node)
12893 /* By marking the declaration as instantiated, we avoid
12894 trying to instantiate it. Since instantiate_decl can't
12895 handle local variables, and since we've already done
12896 all that needs to be done, that's the right thing to
12898 if (TREE_CODE (decl) == VAR_DECL)
12899 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12900 if (TREE_CODE (decl) == VAR_DECL
12901 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12902 /* Anonymous aggregates are a special case. */
12903 finish_anon_union (decl);
12904 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12906 DECL_CONTEXT (decl) = current_function_decl;
12907 insert_capture_proxy (decl);
12911 int const_init = false;
12912 maybe_push_decl (decl);
12913 if (TREE_CODE (decl) == VAR_DECL
12914 && DECL_PRETTY_FUNCTION_P (decl))
12916 /* For __PRETTY_FUNCTION__ we have to adjust the
12918 const char *const name
12919 = cxx_printable_name (current_function_decl, 2);
12920 init = cp_fname_init (name, &TREE_TYPE (decl));
12924 tree t = RECUR (init);
12928 /* If we had an initializer but it
12929 instantiated to nothing,
12930 value-initialize the object. This will
12931 only occur when the initializer was a
12932 pack expansion where the parameter packs
12933 used in that expansion were of length
12935 init = build_value_init (TREE_TYPE (decl),
12937 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12938 init = get_target_expr_sfinae (init, complain);
12944 if (TREE_CODE (decl) == VAR_DECL)
12945 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12947 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12952 /* A DECL_EXPR can also be used as an expression, in the condition
12953 clause of an if/for/while construct. */
12958 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12959 RECUR (FOR_INIT_STMT (t));
12960 finish_for_init_stmt (stmt);
12961 tmp = RECUR (FOR_COND (t));
12962 finish_for_cond (tmp, stmt);
12963 tmp = RECUR (FOR_EXPR (t));
12964 finish_for_expr (tmp, stmt);
12965 RECUR (FOR_BODY (t));
12966 finish_for_stmt (stmt);
12969 case RANGE_FOR_STMT:
12972 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12973 decl = RANGE_FOR_DECL (t);
12974 decl = tsubst (decl, args, complain, in_decl);
12975 maybe_push_decl (decl);
12976 expr = RECUR (RANGE_FOR_EXPR (t));
12977 stmt = cp_convert_range_for (stmt, decl, expr);
12978 RECUR (RANGE_FOR_BODY (t));
12979 finish_for_stmt (stmt);
12984 stmt = begin_while_stmt ();
12985 tmp = RECUR (WHILE_COND (t));
12986 finish_while_stmt_cond (tmp, stmt);
12987 RECUR (WHILE_BODY (t));
12988 finish_while_stmt (stmt);
12992 stmt = begin_do_stmt ();
12993 RECUR (DO_BODY (t));
12994 finish_do_body (stmt);
12995 tmp = RECUR (DO_COND (t));
12996 finish_do_stmt (tmp, stmt);
13000 stmt = begin_if_stmt ();
13001 tmp = RECUR (IF_COND (t));
13002 finish_if_stmt_cond (tmp, stmt);
13003 RECUR (THEN_CLAUSE (t));
13004 finish_then_clause (stmt);
13006 if (ELSE_CLAUSE (t))
13008 begin_else_clause (stmt);
13009 RECUR (ELSE_CLAUSE (t));
13010 finish_else_clause (stmt);
13013 finish_if_stmt (stmt);
13017 if (BIND_EXPR_BODY_BLOCK (t))
13018 stmt = begin_function_body ();
13020 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
13021 ? BCS_TRY_BLOCK : 0);
13023 RECUR (BIND_EXPR_BODY (t));
13025 if (BIND_EXPR_BODY_BLOCK (t))
13026 finish_function_body (stmt);
13028 finish_compound_stmt (stmt);
13032 finish_break_stmt ();
13035 case CONTINUE_STMT:
13036 finish_continue_stmt ();
13040 stmt = begin_switch_stmt ();
13041 tmp = RECUR (SWITCH_STMT_COND (t));
13042 finish_switch_cond (tmp, stmt);
13043 RECUR (SWITCH_STMT_BODY (t));
13044 finish_switch_stmt (stmt);
13047 case CASE_LABEL_EXPR:
13048 finish_case_label (EXPR_LOCATION (t),
13049 RECUR (CASE_LOW (t)),
13050 RECUR (CASE_HIGH (t)));
13055 tree decl = LABEL_EXPR_LABEL (t);
13058 label = finish_label_stmt (DECL_NAME (decl));
13059 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
13060 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
13065 tmp = GOTO_DESTINATION (t);
13066 if (TREE_CODE (tmp) != LABEL_DECL)
13067 /* Computed goto's must be tsubst'd into. On the other hand,
13068 non-computed gotos must not be; the identifier in question
13069 will have no binding. */
13072 tmp = DECL_NAME (tmp);
13073 finish_goto_stmt (tmp);
13077 tmp = finish_asm_stmt
13078 (ASM_VOLATILE_P (t),
13079 RECUR (ASM_STRING (t)),
13080 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13081 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13082 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13083 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13085 tree asm_expr = tmp;
13086 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13087 asm_expr = TREE_OPERAND (asm_expr, 0);
13088 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13095 stmt = begin_try_block ();
13096 RECUR (TRY_STMTS (t));
13097 finish_cleanup_try_block (stmt);
13098 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13102 tree compound_stmt = NULL_TREE;
13104 if (FN_TRY_BLOCK_P (t))
13105 stmt = begin_function_try_block (&compound_stmt);
13107 stmt = begin_try_block ();
13109 RECUR (TRY_STMTS (t));
13111 if (FN_TRY_BLOCK_P (t))
13112 finish_function_try_block (stmt);
13114 finish_try_block (stmt);
13116 RECUR (TRY_HANDLERS (t));
13117 if (FN_TRY_BLOCK_P (t))
13118 finish_function_handler_sequence (stmt, compound_stmt);
13120 finish_handler_sequence (stmt);
13126 tree decl = HANDLER_PARMS (t);
13130 decl = tsubst (decl, args, complain, in_decl);
13131 /* Prevent instantiate_decl from trying to instantiate
13132 this variable. We've already done all that needs to be
13134 if (decl != error_mark_node)
13135 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13137 stmt = begin_handler ();
13138 finish_handler_parms (decl, stmt);
13139 RECUR (HANDLER_BODY (t));
13140 finish_handler (stmt);
13145 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13148 case STATIC_ASSERT:
13151 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13154 /*integral_constant_expression_p=*/true);
13155 finish_static_assert (condition,
13156 STATIC_ASSERT_MESSAGE (t),
13157 STATIC_ASSERT_SOURCE_LOCATION (t),
13158 /*member_p=*/false);
13163 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13164 args, complain, in_decl);
13165 stmt = begin_omp_parallel ();
13166 RECUR (OMP_PARALLEL_BODY (t));
13167 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13168 = OMP_PARALLEL_COMBINED (t);
13172 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13173 args, complain, in_decl);
13174 stmt = begin_omp_task ();
13175 RECUR (OMP_TASK_BODY (t));
13176 finish_omp_task (tmp, stmt);
13181 tree clauses, body, pre_body;
13182 tree declv, initv, condv, incrv;
13185 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13186 args, complain, in_decl);
13187 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13188 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13189 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13190 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13192 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13193 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13194 &clauses, args, complain, in_decl,
13195 integral_constant_expression_p);
13197 stmt = begin_omp_structured_block ();
13199 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13200 if (TREE_VEC_ELT (initv, i) == NULL
13201 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13202 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13203 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13205 tree init = RECUR (TREE_VEC_ELT (initv, i));
13206 gcc_assert (init == TREE_VEC_ELT (declv, i));
13207 TREE_VEC_ELT (initv, i) = NULL_TREE;
13211 tree decl_expr = TREE_VEC_ELT (initv, i);
13212 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13213 gcc_assert (init != NULL);
13214 TREE_VEC_ELT (initv, i) = RECUR (init);
13215 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13217 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13220 pre_body = push_stmt_list ();
13221 RECUR (OMP_FOR_PRE_BODY (t));
13222 pre_body = pop_stmt_list (pre_body);
13224 body = push_stmt_list ();
13225 RECUR (OMP_FOR_BODY (t));
13226 body = pop_stmt_list (body);
13228 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13229 body, pre_body, clauses);
13231 add_stmt (finish_omp_structured_block (stmt));
13237 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13238 stmt = push_stmt_list ();
13239 RECUR (OMP_BODY (t));
13240 stmt = pop_stmt_list (stmt);
13243 OMP_BODY (t) = stmt;
13244 OMP_CLAUSES (t) = tmp;
13252 stmt = push_stmt_list ();
13253 RECUR (OMP_BODY (t));
13254 stmt = pop_stmt_list (stmt);
13257 OMP_BODY (t) = stmt;
13262 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13263 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13265 tree op1 = TREE_OPERAND (t, 1);
13266 tree rhs1 = NULL_TREE;
13268 if (TREE_CODE (op1) == COMPOUND_EXPR)
13270 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13271 op1 = TREE_OPERAND (op1, 1);
13273 lhs = RECUR (TREE_OPERAND (op1, 0));
13274 rhs = RECUR (TREE_OPERAND (op1, 1));
13275 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13276 NULL_TREE, NULL_TREE, rhs1);
13280 tree op1 = TREE_OPERAND (t, 1);
13281 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13282 tree rhs1 = NULL_TREE;
13283 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13284 enum tree_code opcode = NOP_EXPR;
13285 if (code == OMP_ATOMIC_READ)
13287 v = RECUR (TREE_OPERAND (op1, 0));
13288 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13290 else if (code == OMP_ATOMIC_CAPTURE_OLD
13291 || code == OMP_ATOMIC_CAPTURE_NEW)
13293 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13294 v = RECUR (TREE_OPERAND (op1, 0));
13295 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13296 if (TREE_CODE (op11) == COMPOUND_EXPR)
13298 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13299 op11 = TREE_OPERAND (op11, 1);
13301 lhs = RECUR (TREE_OPERAND (op11, 0));
13302 rhs = RECUR (TREE_OPERAND (op11, 1));
13303 opcode = TREE_CODE (op11);
13308 lhs = RECUR (TREE_OPERAND (op1, 0));
13309 rhs = RECUR (TREE_OPERAND (op1, 1));
13311 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13315 case TRANSACTION_EXPR:
13318 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13319 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13321 if (TRANSACTION_EXPR_IS_STMT (t))
13323 tree body = TRANSACTION_EXPR_BODY (t);
13324 tree noex = NULL_TREE;
13325 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13327 noex = MUST_NOT_THROW_COND (body);
13328 if (noex == NULL_TREE)
13329 noex = boolean_true_node;
13330 body = TREE_OPERAND (body, 0);
13332 stmt = begin_transaction_stmt (input_location, NULL, flags);
13334 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13338 stmt = build_transaction_expr (EXPR_LOCATION (t),
13339 RECUR (TRANSACTION_EXPR_BODY (t)),
13346 case MUST_NOT_THROW_EXPR:
13347 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13348 RECUR (MUST_NOT_THROW_COND (t)));
13350 case EXPR_PACK_EXPANSION:
13351 error ("invalid use of pack expansion expression");
13352 return error_mark_node;
13354 case NONTYPE_ARGUMENT_PACK:
13355 error ("use %<...%> to expand argument pack");
13356 return error_mark_node;
13359 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13361 return tsubst_copy_and_build (t, args, complain, in_decl,
13362 /*function_p=*/false,
13363 integral_constant_expression_p);
13370 /* T is a postfix-expression that is not being used in a function
13371 call. Return the substituted version of T. */
13374 tsubst_non_call_postfix_expression (tree t, tree args,
13375 tsubst_flags_t complain,
13378 if (TREE_CODE (t) == SCOPE_REF)
13379 t = tsubst_qualified_id (t, args, complain, in_decl,
13380 /*done=*/false, /*address_p=*/false);
13382 t = tsubst_copy_and_build (t, args, complain, in_decl,
13383 /*function_p=*/false,
13384 /*integral_constant_expression_p=*/false);
13389 /* Like tsubst but deals with expressions and performs semantic
13390 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13393 tsubst_copy_and_build (tree t,
13395 tsubst_flags_t complain,
13398 bool integral_constant_expression_p)
13400 #define RECUR(NODE) \
13401 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13402 /*function_p=*/false, \
13403 integral_constant_expression_p)
13407 if (t == NULL_TREE || t == error_mark_node)
13410 switch (TREE_CODE (t))
13414 /* Fall through. */
13415 case IDENTIFIER_NODE:
13419 bool non_integral_constant_expression_p;
13420 const char *error_msg;
13422 if (IDENTIFIER_TYPENAME_P (t))
13424 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13425 t = mangle_conv_op_name_for_type (new_type);
13428 /* Look up the name. */
13429 decl = lookup_name (t);
13431 /* By convention, expressions use ERROR_MARK_NODE to indicate
13432 failure, not NULL_TREE. */
13433 if (decl == NULL_TREE)
13434 decl = error_mark_node;
13436 decl = finish_id_expression (t, decl, NULL_TREE,
13438 integral_constant_expression_p,
13439 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13440 &non_integral_constant_expression_p,
13441 /*template_p=*/false,
13443 /*address_p=*/false,
13444 /*template_arg_p=*/false,
13449 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13451 if (complain & tf_error)
13452 unqualified_name_lookup_error (decl);
13453 decl = error_mark_node;
13458 case TEMPLATE_ID_EXPR:
13461 tree templ = RECUR (TREE_OPERAND (t, 0));
13462 tree targs = TREE_OPERAND (t, 1);
13465 targs = tsubst_template_args (targs, args, complain, in_decl);
13467 if (TREE_CODE (templ) == COMPONENT_REF)
13469 object = TREE_OPERAND (templ, 0);
13470 templ = TREE_OPERAND (templ, 1);
13473 object = NULL_TREE;
13474 templ = lookup_template_function (templ, targs);
13477 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13478 object, templ, NULL_TREE);
13480 return baselink_for_fns (templ);
13485 tree r = RECUR (TREE_OPERAND (t, 0));
13487 if (REFERENCE_REF_P (t))
13489 /* A type conversion to reference type will be enclosed in
13490 such an indirect ref, but the substitution of the cast
13491 will have also added such an indirect ref. */
13492 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13493 r = convert_from_reference (r);
13496 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13502 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13503 RECUR (TREE_OPERAND (t, 0)));
13505 case IMPLICIT_CONV_EXPR:
13507 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13508 tree expr = RECUR (TREE_OPERAND (t, 0));
13509 int flags = LOOKUP_IMPLICIT;
13510 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13511 flags = LOOKUP_NORMAL;
13512 return perform_implicit_conversion_flags (type, expr, complain,
13519 tsubst (TREE_TYPE (t), args, complain, in_decl),
13520 RECUR (TREE_OPERAND (t, 0)));
13523 case REINTERPRET_CAST_EXPR:
13524 case CONST_CAST_EXPR:
13525 case DYNAMIC_CAST_EXPR:
13526 case STATIC_CAST_EXPR:
13531 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13532 if (integral_constant_expression_p
13533 && !cast_valid_in_integral_constant_expression_p (type))
13535 if (complain & tf_error)
13536 error ("a cast to a type other than an integral or "
13537 "enumeration type cannot appear in a constant-expression");
13538 return error_mark_node;
13541 op = RECUR (TREE_OPERAND (t, 0));
13543 switch (TREE_CODE (t))
13546 return build_functional_cast (type, op, complain);
13547 case REINTERPRET_CAST_EXPR:
13548 return build_reinterpret_cast (type, op, complain);
13549 case CONST_CAST_EXPR:
13550 return build_const_cast (type, op, complain);
13551 case DYNAMIC_CAST_EXPR:
13552 return build_dynamic_cast (type, op, complain);
13553 case STATIC_CAST_EXPR:
13554 return build_static_cast (type, op, complain);
13556 gcc_unreachable ();
13560 case POSTDECREMENT_EXPR:
13561 case POSTINCREMENT_EXPR:
13562 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13563 args, complain, in_decl);
13564 return build_x_unary_op (TREE_CODE (t), op1, complain);
13566 case PREDECREMENT_EXPR:
13567 case PREINCREMENT_EXPR:
13571 case TRUTH_NOT_EXPR:
13572 case UNARY_PLUS_EXPR: /* Unary + */
13573 case REALPART_EXPR:
13574 case IMAGPART_EXPR:
13575 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13578 case FIX_TRUNC_EXPR:
13579 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13583 op1 = TREE_OPERAND (t, 0);
13584 if (TREE_CODE (op1) == LABEL_DECL)
13585 return finish_label_address_expr (DECL_NAME (op1),
13586 EXPR_LOCATION (op1));
13587 if (TREE_CODE (op1) == SCOPE_REF)
13588 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13589 /*done=*/true, /*address_p=*/true);
13591 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13593 return build_x_unary_op (ADDR_EXPR, op1, complain);
13598 case TRUNC_DIV_EXPR:
13599 case CEIL_DIV_EXPR:
13600 case FLOOR_DIV_EXPR:
13601 case ROUND_DIV_EXPR:
13602 case EXACT_DIV_EXPR:
13606 case TRUNC_MOD_EXPR:
13607 case FLOOR_MOD_EXPR:
13608 case TRUTH_ANDIF_EXPR:
13609 case TRUTH_ORIF_EXPR:
13610 case TRUTH_AND_EXPR:
13611 case TRUTH_OR_EXPR:
13627 tree r = build_x_binary_op
13629 RECUR (TREE_OPERAND (t, 0)),
13630 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13632 : TREE_CODE (TREE_OPERAND (t, 0))),
13633 RECUR (TREE_OPERAND (t, 1)),
13634 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13636 : TREE_CODE (TREE_OPERAND (t, 1))),
13639 if (EXPR_P (r) && TREE_NO_WARNING (t))
13640 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13645 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13646 /*address_p=*/false);
13648 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13649 args, complain, in_decl);
13650 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13653 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13654 return tsubst_copy (t, args, complain, in_decl);
13658 op1 = TREE_OPERAND (t, 0);
13661 /* When there are no ARGS, we are trying to evaluate a
13662 non-dependent expression from the parser. Trying to do
13663 the substitutions may not work. */
13665 op1 = TREE_TYPE (op1);
13669 ++cp_unevaluated_operand;
13670 ++c_inhibit_evaluation_warnings;
13671 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13672 /*function_p=*/false,
13673 /*integral_constant_expression_p=*/false);
13674 --cp_unevaluated_operand;
13675 --c_inhibit_evaluation_warnings;
13678 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13679 complain & tf_error);
13681 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13682 complain & tf_error);
13684 case AT_ENCODE_EXPR:
13686 op1 = TREE_OPERAND (t, 0);
13687 ++cp_unevaluated_operand;
13688 ++c_inhibit_evaluation_warnings;
13689 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13690 /*function_p=*/false,
13691 /*integral_constant_expression_p=*/false);
13692 --cp_unevaluated_operand;
13693 --c_inhibit_evaluation_warnings;
13694 return objc_build_encode_expr (op1);
13697 case NOEXCEPT_EXPR:
13698 op1 = TREE_OPERAND (t, 0);
13699 ++cp_unevaluated_operand;
13700 ++c_inhibit_evaluation_warnings;
13701 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13702 /*function_p=*/false,
13703 /*integral_constant_expression_p=*/false);
13704 --cp_unevaluated_operand;
13705 --c_inhibit_evaluation_warnings;
13706 return finish_noexcept_expr (op1, complain);
13710 tree r = build_x_modify_expr
13711 (RECUR (TREE_OPERAND (t, 0)),
13712 TREE_CODE (TREE_OPERAND (t, 1)),
13713 RECUR (TREE_OPERAND (t, 2)),
13715 /* TREE_NO_WARNING must be set if either the expression was
13716 parenthesized or it uses an operator such as >>= rather
13717 than plain assignment. In the former case, it was already
13718 set and must be copied. In the latter case,
13719 build_x_modify_expr sets it and it must not be reset
13721 if (TREE_NO_WARNING (t))
13722 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13727 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13728 args, complain, in_decl);
13729 /* Remember that there was a reference to this entity. */
13732 return build_x_arrow (op1);
13736 tree placement = RECUR (TREE_OPERAND (t, 0));
13737 tree init = RECUR (TREE_OPERAND (t, 3));
13738 VEC(tree,gc) *placement_vec;
13739 VEC(tree,gc) *init_vec;
13742 if (placement == NULL_TREE)
13743 placement_vec = NULL;
13746 placement_vec = make_tree_vector ();
13747 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13748 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13751 /* If there was an initializer in the original tree, but it
13752 instantiated to an empty list, then we should pass a
13753 non-NULL empty vector to tell build_new that it was an
13754 empty initializer() rather than no initializer. This can
13755 only happen when the initializer is a pack expansion whose
13756 parameter packs are of length zero. */
13757 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13761 init_vec = make_tree_vector ();
13762 if (init == void_zero_node)
13763 gcc_assert (init_vec != NULL);
13766 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13767 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13771 ret = build_new (&placement_vec,
13772 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13773 RECUR (TREE_OPERAND (t, 2)),
13775 NEW_EXPR_USE_GLOBAL (t),
13778 if (placement_vec != NULL)
13779 release_tree_vector (placement_vec);
13780 if (init_vec != NULL)
13781 release_tree_vector (init_vec);
13787 return delete_sanity
13788 (RECUR (TREE_OPERAND (t, 0)),
13789 RECUR (TREE_OPERAND (t, 1)),
13790 DELETE_EXPR_USE_VEC (t),
13791 DELETE_EXPR_USE_GLOBAL (t),
13794 case COMPOUND_EXPR:
13795 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13796 RECUR (TREE_OPERAND (t, 1)),
13802 VEC(tree,gc) *call_args;
13803 unsigned int nargs, i;
13808 function = CALL_EXPR_FN (t);
13809 /* When we parsed the expression, we determined whether or
13810 not Koenig lookup should be performed. */
13811 koenig_p = KOENIG_LOOKUP_P (t);
13812 if (TREE_CODE (function) == SCOPE_REF)
13814 qualified_p = true;
13815 function = tsubst_qualified_id (function, args, complain, in_decl,
13817 /*address_p=*/false);
13819 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13821 /* Do nothing; calling tsubst_copy_and_build on an identifier
13822 would incorrectly perform unqualified lookup again.
13824 Note that we can also have an IDENTIFIER_NODE if the earlier
13825 unqualified lookup found a member function; in that case
13826 koenig_p will be false and we do want to do the lookup
13827 again to find the instantiated member function.
13829 FIXME but doing that causes c++/15272, so we need to stop
13830 using IDENTIFIER_NODE in that situation. */
13831 qualified_p = false;
13835 if (TREE_CODE (function) == COMPONENT_REF)
13837 tree op = TREE_OPERAND (function, 1);
13839 qualified_p = (TREE_CODE (op) == SCOPE_REF
13840 || (BASELINK_P (op)
13841 && BASELINK_QUALIFIED_P (op)));
13844 qualified_p = false;
13846 function = tsubst_copy_and_build (function, args, complain,
13849 integral_constant_expression_p);
13851 if (BASELINK_P (function))
13852 qualified_p = true;
13855 nargs = call_expr_nargs (t);
13856 call_args = make_tree_vector ();
13857 for (i = 0; i < nargs; ++i)
13859 tree arg = CALL_EXPR_ARG (t, i);
13861 if (!PACK_EXPANSION_P (arg))
13862 VEC_safe_push (tree, gc, call_args,
13863 RECUR (CALL_EXPR_ARG (t, i)));
13866 /* Expand the pack expansion and push each entry onto
13868 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13869 if (TREE_CODE (arg) == TREE_VEC)
13871 unsigned int len, j;
13873 len = TREE_VEC_LENGTH (arg);
13874 for (j = 0; j < len; ++j)
13876 tree value = TREE_VEC_ELT (arg, j);
13877 if (value != NULL_TREE)
13878 value = convert_from_reference (value);
13879 VEC_safe_push (tree, gc, call_args, value);
13884 /* A partial substitution. Add one entry. */
13885 VEC_safe_push (tree, gc, call_args, arg);
13890 /* We do not perform argument-dependent lookup if normal
13891 lookup finds a non-function, in accordance with the
13892 expected resolution of DR 218. */
13894 && ((is_overloaded_fn (function)
13895 /* If lookup found a member function, the Koenig lookup is
13896 not appropriate, even if an unqualified-name was used
13897 to denote the function. */
13898 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13899 || TREE_CODE (function) == IDENTIFIER_NODE)
13900 /* Only do this when substitution turns a dependent call
13901 into a non-dependent call. */
13902 && type_dependent_expression_p_push (t)
13903 && !any_type_dependent_arguments_p (call_args))
13904 function = perform_koenig_lookup (function, call_args, false,
13907 if (TREE_CODE (function) == IDENTIFIER_NODE
13908 && !any_type_dependent_arguments_p (call_args))
13910 if (koenig_p && (complain & tf_warning_or_error))
13912 /* For backwards compatibility and good diagnostics, try
13913 the unqualified lookup again if we aren't in SFINAE
13915 tree unq = (tsubst_copy_and_build
13916 (function, args, complain, in_decl, true,
13917 integral_constant_expression_p));
13918 if (unq == error_mark_node)
13919 return error_mark_node;
13921 if (unq != function)
13924 if (TREE_CODE (fn) == INDIRECT_REF)
13925 fn = TREE_OPERAND (fn, 0);
13926 if (TREE_CODE (fn) == COMPONENT_REF)
13927 fn = TREE_OPERAND (fn, 1);
13928 if (is_overloaded_fn (fn))
13929 fn = get_first_fn (fn);
13930 permerror (EXPR_LOC_OR_HERE (t),
13931 "%qD was not declared in this scope, "
13932 "and no declarations were found by "
13933 "argument-dependent lookup at the point "
13934 "of instantiation", function);
13936 /* Can't say anything more. */;
13937 else if (DECL_CLASS_SCOPE_P (fn))
13939 inform (EXPR_LOC_OR_HERE (t),
13940 "declarations in dependent base %qT are "
13941 "not found by unqualified lookup",
13942 DECL_CLASS_CONTEXT (fn));
13943 if (current_class_ptr)
13944 inform (EXPR_LOC_OR_HERE (t),
13945 "use %<this->%D%> instead", function);
13947 inform (EXPR_LOC_OR_HERE (t),
13948 "use %<%T::%D%> instead",
13949 current_class_name, function);
13952 inform (0, "%q+D declared here, later in the "
13953 "translation unit", fn);
13957 if (TREE_CODE (function) == IDENTIFIER_NODE)
13959 unqualified_name_lookup_error (function);
13960 release_tree_vector (call_args);
13961 return error_mark_node;
13965 /* Remember that there was a reference to this entity. */
13966 if (DECL_P (function))
13967 mark_used (function);
13969 if (TREE_CODE (function) == OFFSET_REF)
13970 ret = build_offset_ref_call_from_tree (function, &call_args);
13971 else if (TREE_CODE (function) == COMPONENT_REF)
13973 tree instance = TREE_OPERAND (function, 0);
13974 tree fn = TREE_OPERAND (function, 1);
13976 if (processing_template_decl
13977 && (type_dependent_expression_p (instance)
13978 || (!BASELINK_P (fn)
13979 && TREE_CODE (fn) != FIELD_DECL)
13980 || type_dependent_expression_p (fn)
13981 || any_type_dependent_arguments_p (call_args)))
13982 ret = build_nt_call_vec (function, call_args);
13983 else if (!BASELINK_P (fn))
13984 ret = finish_call_expr (function, &call_args,
13985 /*disallow_virtual=*/false,
13986 /*koenig_p=*/false,
13989 ret = (build_new_method_call
13991 &call_args, NULL_TREE,
13992 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13997 ret = finish_call_expr (function, &call_args,
13998 /*disallow_virtual=*/qualified_p,
14002 release_tree_vector (call_args);
14008 return build_x_conditional_expr
14009 (RECUR (TREE_OPERAND (t, 0)),
14010 RECUR (TREE_OPERAND (t, 1)),
14011 RECUR (TREE_OPERAND (t, 2)),
14014 case PSEUDO_DTOR_EXPR:
14015 return finish_pseudo_destructor_expr
14016 (RECUR (TREE_OPERAND (t, 0)),
14017 RECUR (TREE_OPERAND (t, 1)),
14018 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
14022 tree purpose, value, chain;
14024 if (t == void_list_node)
14027 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
14028 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
14030 /* We have pack expansions, so expand those and
14031 create a new list out of it. */
14032 tree purposevec = NULL_TREE;
14033 tree valuevec = NULL_TREE;
14037 /* Expand the argument expressions. */
14038 if (TREE_PURPOSE (t))
14039 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
14040 complain, in_decl);
14041 if (TREE_VALUE (t))
14042 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
14043 complain, in_decl);
14045 /* Build the rest of the list. */
14046 chain = TREE_CHAIN (t);
14047 if (chain && chain != void_type_node)
14048 chain = RECUR (chain);
14050 /* Determine the number of arguments. */
14051 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
14053 len = TREE_VEC_LENGTH (purposevec);
14054 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
14056 else if (TREE_CODE (valuevec) == TREE_VEC)
14057 len = TREE_VEC_LENGTH (valuevec);
14060 /* Since we only performed a partial substitution into
14061 the argument pack, we only return a single list
14063 if (purposevec == TREE_PURPOSE (t)
14064 && valuevec == TREE_VALUE (t)
14065 && chain == TREE_CHAIN (t))
14068 return tree_cons (purposevec, valuevec, chain);
14071 /* Convert the argument vectors into a TREE_LIST */
14075 /* Grab the Ith values. */
14077 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14080 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14083 /* Build the list (backwards). */
14084 chain = tree_cons (purpose, value, chain);
14090 purpose = TREE_PURPOSE (t);
14092 purpose = RECUR (purpose);
14093 value = TREE_VALUE (t);
14095 value = RECUR (value);
14096 chain = TREE_CHAIN (t);
14097 if (chain && chain != void_type_node)
14098 chain = RECUR (chain);
14099 if (purpose == TREE_PURPOSE (t)
14100 && value == TREE_VALUE (t)
14101 && chain == TREE_CHAIN (t))
14103 return tree_cons (purpose, value, chain);
14106 case COMPONENT_REF:
14112 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14113 args, complain, in_decl);
14114 /* Remember that there was a reference to this entity. */
14115 if (DECL_P (object))
14116 mark_used (object);
14117 object_type = TREE_TYPE (object);
14119 member = TREE_OPERAND (t, 1);
14120 if (BASELINK_P (member))
14121 member = tsubst_baselink (member,
14122 non_reference (TREE_TYPE (object)),
14123 args, complain, in_decl);
14125 member = tsubst_copy (member, args, complain, in_decl);
14126 if (member == error_mark_node)
14127 return error_mark_node;
14129 if (type_dependent_expression_p (object))
14130 /* We can't do much here. */;
14131 else if (!CLASS_TYPE_P (object_type))
14133 if (SCALAR_TYPE_P (object_type))
14135 tree s = NULL_TREE;
14136 tree dtor = member;
14138 if (TREE_CODE (dtor) == SCOPE_REF)
14140 s = TREE_OPERAND (dtor, 0);
14141 dtor = TREE_OPERAND (dtor, 1);
14143 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14145 dtor = TREE_OPERAND (dtor, 0);
14147 return finish_pseudo_destructor_expr (object, s, dtor);
14151 else if (TREE_CODE (member) == SCOPE_REF
14152 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14154 /* Lookup the template functions now that we know what the
14156 tree scope = TREE_OPERAND (member, 0);
14157 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14158 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14159 member = lookup_qualified_name (scope, tmpl,
14160 /*is_type_p=*/false,
14161 /*complain=*/false);
14162 if (BASELINK_P (member))
14164 BASELINK_FUNCTIONS (member)
14165 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14167 member = (adjust_result_of_qualified_name_lookup
14168 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14173 qualified_name_lookup_error (scope, tmpl, member,
14175 return error_mark_node;
14178 else if (TREE_CODE (member) == SCOPE_REF
14179 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14180 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14182 if (complain & tf_error)
14184 if (TYPE_P (TREE_OPERAND (member, 0)))
14185 error ("%qT is not a class or namespace",
14186 TREE_OPERAND (member, 0));
14188 error ("%qD is not a class or namespace",
14189 TREE_OPERAND (member, 0));
14191 return error_mark_node;
14193 else if (TREE_CODE (member) == FIELD_DECL)
14194 return finish_non_static_data_member (member, object, NULL_TREE);
14196 return finish_class_member_access_expr (object, member,
14197 /*template_p=*/false,
14203 (RECUR (TREE_OPERAND (t, 0)));
14207 VEC(constructor_elt,gc) *n;
14208 constructor_elt *ce;
14209 unsigned HOST_WIDE_INT idx;
14210 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14211 bool process_index_p;
14213 bool need_copy_p = false;
14216 if (type == error_mark_node)
14217 return error_mark_node;
14219 /* digest_init will do the wrong thing if we let it. */
14220 if (type && TYPE_PTRMEMFUNC_P (type))
14223 /* We do not want to process the index of aggregate
14224 initializers as they are identifier nodes which will be
14225 looked up by digest_init. */
14226 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14228 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14229 newlen = VEC_length (constructor_elt, n);
14230 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14232 if (ce->index && process_index_p)
14233 ce->index = RECUR (ce->index);
14235 if (PACK_EXPANSION_P (ce->value))
14237 /* Substitute into the pack expansion. */
14238 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14241 if (ce->value == error_mark_node
14242 || PACK_EXPANSION_P (ce->value))
14244 else if (TREE_VEC_LENGTH (ce->value) == 1)
14245 /* Just move the argument into place. */
14246 ce->value = TREE_VEC_ELT (ce->value, 0);
14249 /* Update the length of the final CONSTRUCTOR
14250 arguments vector, and note that we will need to
14252 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14253 need_copy_p = true;
14257 ce->value = RECUR (ce->value);
14262 VEC(constructor_elt,gc) *old_n = n;
14264 n = VEC_alloc (constructor_elt, gc, newlen);
14265 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14267 if (TREE_CODE (ce->value) == TREE_VEC)
14269 int i, len = TREE_VEC_LENGTH (ce->value);
14270 for (i = 0; i < len; ++i)
14271 CONSTRUCTOR_APPEND_ELT (n, 0,
14272 TREE_VEC_ELT (ce->value, i));
14275 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14279 r = build_constructor (init_list_type_node, n);
14280 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14282 if (TREE_HAS_CONSTRUCTOR (t))
14283 return finish_compound_literal (type, r, complain);
14285 TREE_TYPE (r) = type;
14291 tree operand_0 = TREE_OPERAND (t, 0);
14292 if (TYPE_P (operand_0))
14294 operand_0 = tsubst (operand_0, args, complain, in_decl);
14295 return get_typeid (operand_0);
14299 operand_0 = RECUR (operand_0);
14300 return build_typeid (operand_0);
14311 tree r = tsubst_copy (t, args, complain, in_decl);
14313 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14314 /* If the original type was a reference, we'll be wrapped in
14315 the appropriate INDIRECT_REF. */
14316 r = convert_from_reference (r);
14321 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14322 tsubst (TREE_TYPE (t), args, complain, in_decl));
14324 case OFFSETOF_EXPR:
14325 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14329 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14330 complain, in_decl);
14332 tree type2 = TRAIT_EXPR_TYPE2 (t);
14334 type2 = tsubst_copy (type2, args, complain, in_decl);
14336 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14341 tree old_stmt_expr = cur_stmt_expr;
14342 tree stmt_expr = begin_stmt_expr ();
14344 cur_stmt_expr = stmt_expr;
14345 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14346 integral_constant_expression_p);
14347 stmt_expr = finish_stmt_expr (stmt_expr, false);
14348 cur_stmt_expr = old_stmt_expr;
14350 /* If the resulting list of expression statement is empty,
14351 fold it further into void_zero_node. */
14352 if (empty_expr_stmt_p (stmt_expr))
14353 stmt_expr = void_zero_node;
14359 t = tsubst_copy (t, args, complain, in_decl);
14360 /* As in finish_id_expression, we resolve enumeration constants
14361 to their underlying values. */
14362 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14364 used_types_insert (TREE_TYPE (t));
14365 return DECL_INITIAL (t);
14371 tree r = build_lambda_expr ();
14373 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14374 LAMBDA_EXPR_CLOSURE (r) = type;
14375 CLASSTYPE_LAMBDA_EXPR (type) = r;
14377 LAMBDA_EXPR_LOCATION (r)
14378 = LAMBDA_EXPR_LOCATION (t);
14379 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14380 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14381 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14382 LAMBDA_EXPR_DISCRIMINATOR (r)
14383 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14384 LAMBDA_EXPR_EXTRA_SCOPE (r)
14385 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14386 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14388 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14389 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14392 LAMBDA_EXPR_RETURN_TYPE (r)
14393 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14395 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14396 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14398 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14399 determine_visibility (TYPE_NAME (type));
14400 /* Now that we know visibility, instantiate the type so we have a
14401 declaration of the op() for later calls to lambda_function. */
14402 complete_type (type);
14404 /* The capture list refers to closure members, so this needs to
14405 wait until after we finish instantiating the type. */
14406 LAMBDA_EXPR_CAPTURE_LIST (r)
14407 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14409 return build_lambda_object (r);
14413 /* We can get here for a constant initializer of non-dependent type.
14414 FIXME stop folding in cp_parser_initializer_clause. */
14415 gcc_assert (TREE_CONSTANT (t));
14417 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14418 TREE_CONSTANT (r) = true;
14422 case TRANSACTION_EXPR:
14423 return tsubst_expr(t, args, complain, in_decl,
14424 integral_constant_expression_p);
14427 /* Handle Objective-C++ constructs, if appropriate. */
14430 = objcp_tsubst_copy_and_build (t, args, complain,
14431 in_decl, /*function_p=*/false);
14435 return tsubst_copy (t, args, complain, in_decl);
14441 /* Verify that the instantiated ARGS are valid. For type arguments,
14442 make sure that the type's linkage is ok. For non-type arguments,
14443 make sure they are constants if they are integral or enumerations.
14444 Emit an error under control of COMPLAIN, and return TRUE on error. */
14447 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14449 if (ARGUMENT_PACK_P (t))
14451 tree vec = ARGUMENT_PACK_ARGS (t);
14452 int len = TREE_VEC_LENGTH (vec);
14453 bool result = false;
14456 for (i = 0; i < len; ++i)
14457 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14461 else if (TYPE_P (t))
14463 /* [basic.link]: A name with no linkage (notably, the name
14464 of a class or enumeration declared in a local scope)
14465 shall not be used to declare an entity with linkage.
14466 This implies that names with no linkage cannot be used as
14469 DR 757 relaxes this restriction for C++0x. */
14470 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14471 : no_linkage_check (t, /*relaxed_p=*/false));
14475 /* DR 488 makes use of a type with no linkage cause
14476 type deduction to fail. */
14477 if (complain & tf_error)
14479 if (TYPE_ANONYMOUS_P (nt))
14480 error ("%qT is/uses anonymous type", t);
14482 error ("template argument for %qD uses local type %qT",
14487 /* In order to avoid all sorts of complications, we do not
14488 allow variably-modified types as template arguments. */
14489 else if (variably_modified_type_p (t, NULL_TREE))
14491 if (complain & tf_error)
14492 error ("%qT is a variably modified type", t);
14496 /* A non-type argument of integral or enumerated type must be a
14498 else if (TREE_TYPE (t)
14499 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14500 && !TREE_CONSTANT (t))
14502 if (complain & tf_error)
14503 error ("integral expression %qE is not constant", t);
14510 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14512 int ix, len = DECL_NTPARMS (tmpl);
14513 bool result = false;
14515 for (ix = 0; ix != len; ix++)
14517 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14520 if (result && (complain & tf_error))
14521 error (" trying to instantiate %qD", tmpl);
14525 /* In C++0x, it's possible to have a function template whose type depends
14526 on itself recursively. This is most obvious with decltype, but can also
14527 occur with enumeration scope (c++/48969). So we need to catch infinite
14528 recursion and reject the substitution at deduction time; this function
14529 will return error_mark_node for any repeated substitution.
14531 This also catches excessive recursion such as when f<N> depends on
14532 f<N-1> across all integers, and returns error_mark_node for all the
14533 substitutions back up to the initial one.
14535 This is, of course, not reentrant. */
14538 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14540 static bool excessive_deduction_depth;
14541 static int deduction_depth;
14542 struct pending_template *old_last_pend = last_pending_template;
14543 struct tinst_level *old_error_tinst = last_error_tinst_level;
14545 tree fntype = TREE_TYPE (fn);
14549 if (excessive_deduction_depth)
14550 return error_mark_node;
14552 tinst = build_tree_list (fn, targs);
14553 if (!push_tinst_level (tinst))
14555 excessive_deduction_depth = true;
14557 return error_mark_node;
14560 input_location = DECL_SOURCE_LOCATION (fn);
14562 push_deduction_access_scope (fn);
14563 r = tsubst (fntype, targs, complain, NULL_TREE);
14564 pop_deduction_access_scope (fn);
14567 if (excessive_deduction_depth)
14569 r = error_mark_node;
14570 if (deduction_depth == 0)
14571 /* Reset once we're all the way out. */
14572 excessive_deduction_depth = false;
14575 pop_tinst_level ();
14576 /* We can't free this if a pending_template entry or last_error_tinst_level
14577 is pointing at it. */
14578 if (last_pending_template == old_last_pend
14579 && last_error_tinst_level == old_error_tinst)
14584 /* Instantiate the indicated variable or function template TMPL with
14585 the template arguments in TARG_PTR. */
14588 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14590 tree targ_ptr = orig_args;
14595 if (tmpl == error_mark_node)
14596 return error_mark_node;
14598 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14600 /* If this function is a clone, handle it specially. */
14601 if (DECL_CLONED_FUNCTION_P (tmpl))
14606 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14607 DECL_CLONED_FUNCTION. */
14608 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14609 targ_ptr, complain);
14610 if (spec == error_mark_node)
14611 return error_mark_node;
14613 /* Look for the clone. */
14614 FOR_EACH_CLONE (clone, spec)
14615 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14617 /* We should always have found the clone by now. */
14618 gcc_unreachable ();
14622 /* Check to see if we already have this specialization. */
14623 gen_tmpl = most_general_template (tmpl);
14624 if (tmpl != gen_tmpl)
14625 /* The TMPL is a partial instantiation. To get a full set of
14626 arguments we must add the arguments used to perform the
14627 partial instantiation. */
14628 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14631 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14632 but it doesn't seem to be on the hot path. */
14633 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14635 gcc_assert (tmpl == gen_tmpl
14636 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14638 || fndecl == NULL_TREE);
14640 if (spec != NULL_TREE)
14643 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14645 return error_mark_node;
14647 /* We are building a FUNCTION_DECL, during which the access of its
14648 parameters and return types have to be checked. However this
14649 FUNCTION_DECL which is the desired context for access checking
14650 is not built yet. We solve this chicken-and-egg problem by
14651 deferring all checks until we have the FUNCTION_DECL. */
14652 push_deferring_access_checks (dk_deferred);
14654 /* Instantiation of the function happens in the context of the function
14655 template, not the context of the overload resolution we're doing. */
14656 push_to_top_level ();
14657 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14659 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr,
14660 complain, gen_tmpl);
14661 push_nested_class (ctx);
14663 /* Substitute template parameters to obtain the specialization. */
14664 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14665 targ_ptr, complain, gen_tmpl);
14666 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14667 pop_nested_class ();
14668 pop_from_top_level ();
14670 if (fndecl == error_mark_node)
14671 return error_mark_node;
14673 /* Now we know the specialization, compute access previously
14675 push_access_scope (fndecl);
14677 /* Some typedefs referenced from within the template code need to be access
14678 checked at template instantiation time, i.e now. These types were
14679 added to the template at parsing time. Let's get those and perfom
14680 the acces checks then. */
14681 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14682 perform_deferred_access_checks ();
14683 pop_access_scope (fndecl);
14684 pop_deferring_access_checks ();
14686 /* The DECL_TI_TEMPLATE should always be the immediate parent
14687 template, not the most general template. */
14688 DECL_TI_TEMPLATE (fndecl) = tmpl;
14690 /* If we've just instantiated the main entry point for a function,
14691 instantiate all the alternate entry points as well. We do this
14692 by cloning the instantiation of the main entry point, not by
14693 instantiating the template clones. */
14694 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14695 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14700 /* Wrapper for instantiate_template_1. */
14703 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14706 timevar_push (TV_TEMPLATE_INST);
14707 ret = instantiate_template_1 (tmpl, orig_args, complain);
14708 timevar_pop (TV_TEMPLATE_INST);
14712 /* We're going to do deduction substitution on the type of TMPL, a function
14713 template. In C++11 mode, push into that access scope. In C++03 mode,
14714 disable access checking. */
14717 push_deduction_access_scope (tree tmpl)
14719 if (cxx_dialect >= cxx0x)
14721 int ptd = processing_template_decl;
14722 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14723 /* Preserve processing_template_decl across push_to_top_level. */
14724 if (ptd && !processing_template_decl)
14725 ++processing_template_decl;
14728 push_deferring_access_checks (dk_no_check);
14731 /* And pop back out. */
14734 pop_deduction_access_scope (tree tmpl)
14736 if (cxx_dialect >= cxx0x)
14737 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14739 pop_deferring_access_checks ();
14742 /* PARM is a template parameter pack for FN. Returns true iff
14743 PARM is used in a deducible way in the argument list of FN. */
14746 pack_deducible_p (tree parm, tree fn)
14748 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14749 for (; t; t = TREE_CHAIN (t))
14751 tree type = TREE_VALUE (t);
14753 if (!PACK_EXPANSION_P (type))
14755 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14756 packs; packs = TREE_CHAIN (packs))
14757 if (TREE_VALUE (packs) == parm)
14759 /* The template parameter pack is used in a function parameter
14760 pack. If this is the end of the parameter list, the
14761 template parameter pack is deducible. */
14762 if (TREE_CHAIN (t) == void_list_node)
14765 /* Otherwise, not. Well, it could be deduced from
14766 a non-pack parameter, but doing so would end up with
14767 a deduction mismatch, so don't bother. */
14771 /* The template parameter pack isn't used in any function parameter
14772 packs, but it might be used deeper, e.g. tuple<Args...>. */
14776 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14777 NARGS elements of the arguments that are being used when calling
14778 it. TARGS is a vector into which the deduced template arguments
14781 Return zero for success, 2 for an incomplete match that doesn't resolve
14782 all the types, and 1 for complete failure. An error message will be
14783 printed only for an incomplete match.
14785 If FN is a conversion operator, or we are trying to produce a specific
14786 specialization, RETURN_TYPE is the return type desired.
14788 The EXPLICIT_TARGS are explicit template arguments provided via a
14791 The parameter STRICT is one of:
14794 We are deducing arguments for a function call, as in
14795 [temp.deduct.call].
14798 We are deducing arguments for a conversion function, as in
14799 [temp.deduct.conv].
14802 We are deducing arguments when doing an explicit instantiation
14803 as in [temp.explicit], when determining an explicit specialization
14804 as in [temp.expl.spec], or when taking the address of a function
14805 template, as in [temp.deduct.funcaddr]. */
14808 fn_type_unification (tree fn,
14809 tree explicit_targs,
14812 unsigned int nargs,
14814 unification_kind_t strict,
14822 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14824 fntype = TREE_TYPE (fn);
14825 if (explicit_targs)
14829 The specified template arguments must match the template
14830 parameters in kind (i.e., type, nontype, template), and there
14831 must not be more arguments than there are parameters;
14832 otherwise type deduction fails.
14834 Nontype arguments must match the types of the corresponding
14835 nontype template parameters, or must be convertible to the
14836 types of the corresponding nontype parameters as specified in
14837 _temp.arg.nontype_, otherwise type deduction fails.
14839 All references in the function type of the function template
14840 to the corresponding template parameters are replaced by the
14841 specified template argument values. If a substitution in a
14842 template parameter or in the function type of the function
14843 template results in an invalid type, type deduction fails. */
14844 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14845 int i, len = TREE_VEC_LENGTH (tparms);
14846 tree converted_args;
14847 bool incomplete = false;
14849 if (explicit_targs == error_mark_node)
14850 return unify_invalid (explain_p);
14853 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14855 ? tf_warning_or_error
14857 /*require_all_args=*/false,
14858 /*use_default_args=*/false));
14859 if (converted_args == error_mark_node)
14862 /* Substitute the explicit args into the function type. This is
14863 necessary so that, for instance, explicitly declared function
14864 arguments can match null pointed constants. If we were given
14865 an incomplete set of explicit args, we must not do semantic
14866 processing during substitution as we could create partial
14868 for (i = 0; i < len; i++)
14870 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14871 bool parameter_pack = false;
14872 tree targ = TREE_VEC_ELT (converted_args, i);
14874 /* Dig out the actual parm. */
14875 if (TREE_CODE (parm) == TYPE_DECL
14876 || TREE_CODE (parm) == TEMPLATE_DECL)
14878 parm = TREE_TYPE (parm);
14879 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14881 else if (TREE_CODE (parm) == PARM_DECL)
14883 parm = DECL_INITIAL (parm);
14884 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14887 if (!parameter_pack && targ == NULL_TREE)
14888 /* No explicit argument for this template parameter. */
14891 if (parameter_pack && pack_deducible_p (parm, fn))
14893 /* Mark the argument pack as "incomplete". We could
14894 still deduce more arguments during unification.
14895 We remove this mark in type_unification_real. */
14898 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14899 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14900 = ARGUMENT_PACK_ARGS (targ);
14903 /* We have some incomplete argument packs. */
14908 processing_template_decl += incomplete;
14909 fntype = deduction_tsubst_fntype (fn, converted_args,
14911 ? tf_warning_or_error
14913 processing_template_decl -= incomplete;
14915 if (fntype == error_mark_node)
14918 /* Place the explicitly specified arguments in TARGS. */
14919 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14920 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14923 /* Never do unification on the 'this' parameter. */
14924 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14930 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14931 new_args = XALLOCAVEC (tree, nargs + 1);
14932 new_args[0] = return_type;
14933 memcpy (new_args + 1, args, nargs * sizeof (tree));
14938 /* We allow incomplete unification without an error message here
14939 because the standard doesn't seem to explicitly prohibit it. Our
14940 callers must be ready to deal with unification failures in any
14942 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14943 targs, parms, args, nargs, /*subr=*/0,
14944 strict, flags, explain_p);
14946 /* Now that we have bindings for all of the template arguments,
14947 ensure that the arguments deduced for the template template
14948 parameters have compatible template parameter lists. We cannot
14949 check this property before we have deduced all template
14950 arguments, because the template parameter types of a template
14951 template parameter might depend on prior template parameters
14952 deduced after the template template parameter. The following
14953 ill-formed example illustrates this issue:
14955 template<typename T, template<T> class C> void f(C<5>, T);
14957 template<int N> struct X {};
14960 f(X<5>(), 5l); // error: template argument deduction fails
14963 The template parameter list of 'C' depends on the template type
14964 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14965 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14966 time that we deduce 'C'. */
14968 && !template_template_parm_bindings_ok_p
14969 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14970 return unify_inconsistent_template_template_parameters (explain_p);
14973 /* All is well so far. Now, check:
14977 When all template arguments have been deduced, all uses of
14978 template parameters in nondeduced contexts are replaced with
14979 the corresponding deduced argument values. If the
14980 substitution results in an invalid type, as described above,
14981 type deduction fails. */
14983 tree substed = deduction_tsubst_fntype (fn, targs,
14985 ? tf_warning_or_error
14987 if (substed == error_mark_node)
14990 /* If we're looking for an exact match, check that what we got
14991 is indeed an exact match. It might not be if some template
14992 parameters are used in non-deduced contexts. */
14993 if (strict == DEDUCE_EXACT)
14998 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
15000 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
15001 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
15002 if (!same_type_p (args[i], TREE_VALUE (sarg)))
15003 return unify_type_mismatch (explain_p, args[i],
15004 TREE_VALUE (sarg));
15011 /* Adjust types before performing type deduction, as described in
15012 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
15013 sections are symmetric. PARM is the type of a function parameter
15014 or the return type of the conversion function. ARG is the type of
15015 the argument passed to the call, or the type of the value
15016 initialized with the result of the conversion function.
15017 ARG_EXPR is the original argument expression, which may be null. */
15020 maybe_adjust_types_for_deduction (unification_kind_t strict,
15034 /* Swap PARM and ARG throughout the remainder of this
15035 function; the handling is precisely symmetric since PARM
15036 will initialize ARG rather than vice versa. */
15044 /* Core issue #873: Do the DR606 thing (see below) for these cases,
15045 too, but here handle it by stripping the reference from PARM
15046 rather than by adding it to ARG. */
15047 if (TREE_CODE (*parm) == REFERENCE_TYPE
15048 && TYPE_REF_IS_RVALUE (*parm)
15049 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15050 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15051 && TREE_CODE (*arg) == REFERENCE_TYPE
15052 && !TYPE_REF_IS_RVALUE (*arg))
15053 *parm = TREE_TYPE (*parm);
15054 /* Nothing else to do in this case. */
15058 gcc_unreachable ();
15061 if (TREE_CODE (*parm) != REFERENCE_TYPE)
15063 /* [temp.deduct.call]
15065 If P is not a reference type:
15067 --If A is an array type, the pointer type produced by the
15068 array-to-pointer standard conversion (_conv.array_) is
15069 used in place of A for type deduction; otherwise,
15071 --If A is a function type, the pointer type produced by
15072 the function-to-pointer standard conversion
15073 (_conv.func_) is used in place of A for type deduction;
15076 --If A is a cv-qualified type, the top level
15077 cv-qualifiers of A's type are ignored for type
15079 if (TREE_CODE (*arg) == ARRAY_TYPE)
15080 *arg = build_pointer_type (TREE_TYPE (*arg));
15081 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15082 *arg = build_pointer_type (*arg);
15084 *arg = TYPE_MAIN_VARIANT (*arg);
15087 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15088 of the form T&&, where T is a template parameter, and the argument
15089 is an lvalue, T is deduced as A& */
15090 if (TREE_CODE (*parm) == REFERENCE_TYPE
15091 && TYPE_REF_IS_RVALUE (*parm)
15092 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15093 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15094 && (arg_expr ? real_lvalue_p (arg_expr)
15095 /* try_one_overload doesn't provide an arg_expr, but
15096 functions are always lvalues. */
15097 : TREE_CODE (*arg) == FUNCTION_TYPE))
15098 *arg = build_reference_type (*arg);
15100 /* [temp.deduct.call]
15102 If P is a cv-qualified type, the top level cv-qualifiers
15103 of P's type are ignored for type deduction. If P is a
15104 reference type, the type referred to by P is used for
15106 *parm = TYPE_MAIN_VARIANT (*parm);
15107 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15109 *parm = TREE_TYPE (*parm);
15110 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15113 /* DR 322. For conversion deduction, remove a reference type on parm
15114 too (which has been swapped into ARG). */
15115 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15116 *arg = TREE_TYPE (*arg);
15121 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15122 template which does contain any deducible template parameters; check if
15123 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15124 unify_one_argument. */
15127 check_non_deducible_conversion (tree parm, tree arg, int strict,
15128 int flags, bool explain_p)
15133 type = TREE_TYPE (arg);
15137 if (same_type_p (parm, type))
15138 return unify_success (explain_p);
15140 if (strict == DEDUCE_CONV)
15142 if (can_convert_arg (type, parm, NULL_TREE, flags))
15143 return unify_success (explain_p);
15145 else if (strict != DEDUCE_EXACT)
15147 if (can_convert_arg (parm, type,
15148 TYPE_P (arg) ? NULL_TREE : arg,
15150 return unify_success (explain_p);
15153 if (strict == DEDUCE_EXACT)
15154 return unify_type_mismatch (explain_p, parm, arg);
15156 return unify_arg_conversion (explain_p, parm, type, arg);
15159 /* Subroutine of type_unification_real and unify_pack_expansion to
15160 handle unification of a single P/A pair. Parameters are as
15161 for those functions. */
15164 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15165 int subr, unification_kind_t strict, int flags,
15168 tree arg_expr = NULL_TREE;
15171 if (arg == error_mark_node || parm == error_mark_node)
15172 return unify_invalid (explain_p);
15173 if (arg == unknown_type_node)
15174 /* We can't deduce anything from this, but we might get all the
15175 template args from other function args. */
15176 return unify_success (explain_p);
15178 /* FIXME uses_deducible_template_parms */
15179 if (TYPE_P (parm) && !uses_template_parms (parm))
15180 return check_non_deducible_conversion (parm, arg, strict, flags,
15186 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15187 | UNIFY_ALLOW_MORE_CV_QUAL
15188 | UNIFY_ALLOW_DERIVED);
15192 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15196 arg_strict = UNIFY_ALLOW_NONE;
15200 gcc_unreachable ();
15203 /* We only do these transformations if this is the top-level
15204 parameter_type_list in a call or declaration matching; in other
15205 situations (nested function declarators, template argument lists) we
15206 won't be comparing a type to an expression, and we don't do any type
15212 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15213 if (type_unknown_p (arg))
15215 /* [temp.deduct.type] A template-argument can be
15216 deduced from a pointer to function or pointer
15217 to member function argument if the set of
15218 overloaded functions does not contain function
15219 templates and at most one of a set of
15220 overloaded functions provides a unique
15223 if (resolve_overloaded_unification
15224 (tparms, targs, parm, arg, strict,
15225 arg_strict, explain_p))
15226 return unify_success (explain_p);
15227 return unify_overload_resolution_failure (explain_p, arg);
15231 arg = unlowered_expr_type (arg);
15232 if (arg == error_mark_node)
15233 return unify_invalid (explain_p);
15237 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15240 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15241 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15243 /* For deduction from an init-list we need the actual list. */
15244 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15246 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15249 /* Most parms like fn_type_unification.
15251 If SUBR is 1, we're being called recursively (to unify the
15252 arguments of a function or method parameter of a function
15256 type_unification_real (tree tparms,
15260 unsigned int xnargs,
15262 unification_kind_t strict,
15268 int ntparms = TREE_VEC_LENGTH (tparms);
15269 int saw_undeduced = 0;
15272 unsigned int nargs;
15275 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15276 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15277 gcc_assert (ntparms > 0);
15279 /* Reset the number of non-defaulted template arguments contained
15281 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15289 while (parms && parms != void_list_node
15292 parm = TREE_VALUE (parms);
15294 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15295 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15296 /* For a function parameter pack that occurs at the end of the
15297 parameter-declaration-list, the type A of each remaining
15298 argument of the call is compared with the type P of the
15299 declarator-id of the function parameter pack. */
15302 parms = TREE_CHAIN (parms);
15304 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15305 /* For a function parameter pack that does not occur at the
15306 end of the parameter-declaration-list, the type of the
15307 parameter pack is a non-deduced context. */
15313 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15319 && parms != void_list_node
15320 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15322 /* Unify the remaining arguments with the pack expansion type. */
15324 tree parmvec = make_tree_vec (1);
15326 /* Allocate a TREE_VEC and copy in all of the arguments */
15327 argvec = make_tree_vec (nargs - ia);
15328 for (i = 0; ia < nargs; ++ia, ++i)
15329 TREE_VEC_ELT (argvec, i) = args[ia];
15331 /* Copy the parameter into parmvec. */
15332 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15333 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15334 /*subr=*/subr, explain_p))
15337 /* Advance to the end of the list of parameters. */
15338 parms = TREE_CHAIN (parms);
15341 /* Fail if we've reached the end of the parm list, and more args
15342 are present, and the parm list isn't variadic. */
15343 if (ia < nargs && parms == void_list_node)
15344 return unify_too_many_arguments (explain_p, nargs, ia);
15345 /* Fail if parms are left and they don't have default values. */
15346 if (parms && parms != void_list_node
15347 && TREE_PURPOSE (parms) == NULL_TREE)
15349 unsigned int count = nargs;
15351 while (p && p != void_list_node)
15354 p = TREE_CHAIN (p);
15356 return unify_too_few_arguments (explain_p, ia, count);
15361 tsubst_flags_t complain = (explain_p
15362 ? tf_warning_or_error
15365 /* Check to see if we need another pass before we start clearing
15366 ARGUMENT_PACK_INCOMPLETE_P. */
15367 for (i = 0; i < ntparms; i++)
15369 tree targ = TREE_VEC_ELT (targs, i);
15370 tree tparm = TREE_VEC_ELT (tparms, i);
15372 if (targ || tparm == error_mark_node)
15374 tparm = TREE_VALUE (tparm);
15376 /* If this is an undeduced nontype parameter that depends on
15377 a type parameter, try another pass; its type may have been
15378 deduced from a later argument than the one from which
15379 this parameter can be deduced. */
15380 if (TREE_CODE (tparm) == PARM_DECL
15381 && uses_template_parms (TREE_TYPE (tparm))
15382 && !saw_undeduced++)
15386 for (i = 0; i < ntparms; i++)
15388 tree targ = TREE_VEC_ELT (targs, i);
15389 tree tparm = TREE_VEC_ELT (tparms, i);
15391 /* Clear the "incomplete" flags on all argument packs now so that
15392 substituting them into later default arguments works. */
15393 if (targ && ARGUMENT_PACK_P (targ))
15395 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15396 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15399 if (targ || tparm == error_mark_node)
15401 tparm = TREE_VALUE (tparm);
15403 /* Core issue #226 (C++0x) [temp.deduct]:
15405 If a template argument has not been deduced, its
15406 default template argument, if any, is used.
15408 When we are in C++98 mode, TREE_PURPOSE will either
15409 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15410 to explicitly check cxx_dialect here. */
15411 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15413 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15414 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15415 location_t save_loc = input_location;
15417 input_location = DECL_SOURCE_LOCATION (parm);
15418 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15419 arg = convert_template_argument (parm, arg, targs, complain,
15421 input_location = save_loc;
15422 if (arg == error_mark_node)
15426 TREE_VEC_ELT (targs, i) = arg;
15427 /* The position of the first default template argument,
15428 is also the number of non-defaulted arguments in TARGS.
15430 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15431 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15436 /* If the type parameter is a parameter pack, then it will
15437 be deduced to an empty parameter pack. */
15438 if (template_parameter_pack_p (tparm))
15442 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15444 arg = make_node (NONTYPE_ARGUMENT_PACK);
15445 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15446 TREE_CONSTANT (arg) = 1;
15449 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15451 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15453 TREE_VEC_ELT (targs, i) = arg;
15457 return unify_parameter_deduction_failure (explain_p, tparm);
15460 #ifdef ENABLE_CHECKING
15461 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15462 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15465 return unify_success (explain_p);
15468 /* Subroutine of type_unification_real. Args are like the variables
15469 at the call site. ARG is an overloaded function (or template-id);
15470 we try deducing template args from each of the overloads, and if
15471 only one succeeds, we go with that. Modifies TARGS and returns
15472 true on success. */
15475 resolve_overloaded_unification (tree tparms,
15479 unification_kind_t strict,
15483 tree tempargs = copy_node (targs);
15485 tree goodfn = NULL_TREE;
15488 if (TREE_CODE (arg) == ADDR_EXPR)
15490 arg = TREE_OPERAND (arg, 0);
15496 if (TREE_CODE (arg) == COMPONENT_REF)
15497 /* Handle `&x' where `x' is some static or non-static member
15499 arg = TREE_OPERAND (arg, 1);
15501 if (TREE_CODE (arg) == OFFSET_REF)
15502 arg = TREE_OPERAND (arg, 1);
15504 /* Strip baselink information. */
15505 if (BASELINK_P (arg))
15506 arg = BASELINK_FUNCTIONS (arg);
15508 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15510 /* If we got some explicit template args, we need to plug them into
15511 the affected templates before we try to unify, in case the
15512 explicit args will completely resolve the templates in question. */
15515 tree expl_subargs = TREE_OPERAND (arg, 1);
15516 arg = TREE_OPERAND (arg, 0);
15518 for (; arg; arg = OVL_NEXT (arg))
15520 tree fn = OVL_CURRENT (arg);
15521 tree subargs, elem;
15523 if (TREE_CODE (fn) != TEMPLATE_DECL)
15526 ++processing_template_decl;
15527 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15528 expl_subargs, /*check_ret=*/false);
15529 if (subargs && !any_dependent_template_arguments_p (subargs))
15531 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15532 if (try_one_overload (tparms, targs, tempargs, parm,
15533 elem, strict, sub_strict, addr_p, explain_p)
15534 && (!goodfn || !same_type_p (goodfn, elem)))
15542 --processing_template_decl;
15544 /* If no templates (or more than one) are fully resolved by the
15545 explicit arguments, this template-id is a non-deduced context; it
15546 could still be OK if we deduce all template arguments for the
15547 enclosing call through other arguments. */
15551 else if (TREE_CODE (arg) != OVERLOAD
15552 && TREE_CODE (arg) != FUNCTION_DECL)
15553 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15554 -- but the deduction does not succeed because the expression is
15555 not just the function on its own. */
15558 for (; arg; arg = OVL_NEXT (arg))
15559 if (try_one_overload (tparms, targs, tempargs, parm,
15560 TREE_TYPE (OVL_CURRENT (arg)),
15561 strict, sub_strict, addr_p, explain_p)
15562 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15564 goodfn = OVL_CURRENT (arg);
15568 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15569 to function or pointer to member function argument if the set of
15570 overloaded functions does not contain function templates and at most
15571 one of a set of overloaded functions provides a unique match.
15573 So if we found multiple possibilities, we return success but don't
15574 deduce anything. */
15578 int i = TREE_VEC_LENGTH (targs);
15580 if (TREE_VEC_ELT (tempargs, i))
15581 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15589 /* Core DR 115: In contexts where deduction is done and fails, or in
15590 contexts where deduction is not done, if a template argument list is
15591 specified and it, along with any default template arguments, identifies
15592 a single function template specialization, then the template-id is an
15593 lvalue for the function template specialization. */
15596 resolve_nondeduced_context (tree orig_expr)
15598 tree expr, offset, baselink;
15601 if (!type_unknown_p (orig_expr))
15606 offset = NULL_TREE;
15607 baselink = NULL_TREE;
15609 if (TREE_CODE (expr) == ADDR_EXPR)
15611 expr = TREE_OPERAND (expr, 0);
15614 if (TREE_CODE (expr) == OFFSET_REF)
15617 expr = TREE_OPERAND (expr, 1);
15619 if (BASELINK_P (expr))
15622 expr = BASELINK_FUNCTIONS (expr);
15625 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15628 tree goodfn = NULL_TREE;
15630 /* If we got some explicit template args, we need to plug them into
15631 the affected templates before we try to unify, in case the
15632 explicit args will completely resolve the templates in question. */
15634 tree expl_subargs = TREE_OPERAND (expr, 1);
15635 tree arg = TREE_OPERAND (expr, 0);
15636 tree badfn = NULL_TREE;
15637 tree badargs = NULL_TREE;
15639 for (; arg; arg = OVL_NEXT (arg))
15641 tree fn = OVL_CURRENT (arg);
15642 tree subargs, elem;
15644 if (TREE_CODE (fn) != TEMPLATE_DECL)
15647 ++processing_template_decl;
15648 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15649 expl_subargs, /*check_ret=*/false);
15650 if (subargs && !any_dependent_template_arguments_p (subargs))
15652 elem = instantiate_template (fn, subargs, tf_none);
15653 if (elem == error_mark_node)
15658 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15664 --processing_template_decl;
15668 mark_used (goodfn);
15671 expr = build_baselink (BASELINK_BINFO (baselink),
15672 BASELINK_ACCESS_BINFO (baselink),
15673 expr, BASELINK_OPTYPE (baselink));
15677 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15678 expr = build_offset_ref (base, expr, addr);
15681 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15684 else if (good == 0 && badargs)
15685 /* There were no good options and at least one bad one, so let the
15686 user know what the problem is. */
15687 instantiate_template (badfn, badargs, tf_warning_or_error);
15692 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15693 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15694 different overloads deduce different arguments for a given parm.
15695 ADDR_P is true if the expression for which deduction is being
15696 performed was of the form "& fn" rather than simply "fn".
15698 Returns 1 on success. */
15701 try_one_overload (tree tparms,
15706 unification_kind_t strict,
15715 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15716 to function or pointer to member function argument if the set of
15717 overloaded functions does not contain function templates and at most
15718 one of a set of overloaded functions provides a unique match.
15720 So if this is a template, just return success. */
15722 if (uses_template_parms (arg))
15725 if (TREE_CODE (arg) == METHOD_TYPE)
15726 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15728 arg = build_pointer_type (arg);
15730 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15732 /* We don't copy orig_targs for this because if we have already deduced
15733 some template args from previous args, unify would complain when we
15734 try to deduce a template parameter for the same argument, even though
15735 there isn't really a conflict. */
15736 nargs = TREE_VEC_LENGTH (targs);
15737 tempargs = make_tree_vec (nargs);
15739 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15742 /* First make sure we didn't deduce anything that conflicts with
15743 explicitly specified args. */
15744 for (i = nargs; i--; )
15746 tree elt = TREE_VEC_ELT (tempargs, i);
15747 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15751 else if (uses_template_parms (elt))
15752 /* Since we're unifying against ourselves, we will fill in
15753 template args used in the function parm list with our own
15754 template parms. Discard them. */
15755 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15756 else if (oldelt && !template_args_equal (oldelt, elt))
15760 for (i = nargs; i--; )
15762 tree elt = TREE_VEC_ELT (tempargs, i);
15765 TREE_VEC_ELT (targs, i) = elt;
15771 /* PARM is a template class (perhaps with unbound template
15772 parameters). ARG is a fully instantiated type. If ARG can be
15773 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15774 TARGS are as for unify. */
15777 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15780 tree copy_of_targs;
15782 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15783 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15784 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15787 /* We need to make a new template argument vector for the call to
15788 unify. If we used TARGS, we'd clutter it up with the result of
15789 the attempted unification, even if this class didn't work out.
15790 We also don't want to commit ourselves to all the unifications
15791 we've already done, since unification is supposed to be done on
15792 an argument-by-argument basis. In other words, consider the
15793 following pathological case:
15795 template <int I, int J, int K>
15798 template <int I, int J>
15799 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15801 template <int I, int J, int K>
15802 void f(S<I, J, K>, S<I, I, I>);
15811 Now, by the time we consider the unification involving `s2', we
15812 already know that we must have `f<0, 0, 0>'. But, even though
15813 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15814 because there are two ways to unify base classes of S<0, 1, 2>
15815 with S<I, I, I>. If we kept the already deduced knowledge, we
15816 would reject the possibility I=1. */
15817 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15819 /* If unification failed, we're done. */
15820 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15821 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15827 /* Given a template type PARM and a class type ARG, find the unique
15828 base type in ARG that is an instance of PARM. We do not examine
15829 ARG itself; only its base-classes. If there is not exactly one
15830 appropriate base class, return NULL_TREE. PARM may be the type of
15831 a partial specialization, as well as a plain template type. Used
15834 static enum template_base_result
15835 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15836 bool explain_p, tree *result)
15838 tree rval = NULL_TREE;
15841 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15843 binfo = TYPE_BINFO (complete_type (arg));
15846 /* The type could not be completed. */
15847 *result = NULL_TREE;
15848 return tbr_incomplete_type;
15851 /* Walk in inheritance graph order. The search order is not
15852 important, and this avoids multiple walks of virtual bases. */
15853 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15855 tree r = try_class_unification (tparms, targs, parm,
15856 BINFO_TYPE (binfo), explain_p);
15860 /* If there is more than one satisfactory baseclass, then:
15864 If they yield more than one possible deduced A, the type
15868 if (rval && !same_type_p (r, rval))
15870 *result = NULL_TREE;
15871 return tbr_ambiguous_baseclass;
15879 return tbr_success;
15882 /* Returns the level of DECL, which declares a template parameter. */
15885 template_decl_level (tree decl)
15887 switch (TREE_CODE (decl))
15890 case TEMPLATE_DECL:
15891 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15894 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15897 gcc_unreachable ();
15902 /* Decide whether ARG can be unified with PARM, considering only the
15903 cv-qualifiers of each type, given STRICT as documented for unify.
15904 Returns nonzero iff the unification is OK on that basis. */
15907 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15909 int arg_quals = cp_type_quals (arg);
15910 int parm_quals = cp_type_quals (parm);
15912 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15913 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15915 /* Although a CVR qualifier is ignored when being applied to a
15916 substituted template parameter ([8.3.2]/1 for example), that
15917 does not allow us to unify "const T" with "int&" because both
15918 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15919 It is ok when we're allowing additional CV qualifiers
15920 at the outer level [14.8.2.1]/3,1st bullet. */
15921 if ((TREE_CODE (arg) == REFERENCE_TYPE
15922 || TREE_CODE (arg) == FUNCTION_TYPE
15923 || TREE_CODE (arg) == METHOD_TYPE)
15924 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15927 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15928 && (parm_quals & TYPE_QUAL_RESTRICT))
15932 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15933 && (arg_quals & parm_quals) != parm_quals)
15936 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15937 && (parm_quals & arg_quals) != arg_quals)
15943 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15945 template_parm_level_and_index (tree parm, int* level, int* index)
15947 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15948 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15949 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15951 *index = TEMPLATE_TYPE_IDX (parm);
15952 *level = TEMPLATE_TYPE_LEVEL (parm);
15956 *index = TEMPLATE_PARM_IDX (parm);
15957 *level = TEMPLATE_PARM_LEVEL (parm);
15961 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15963 if (unify (TP, TA, P, A, S, EP)) \
15967 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15968 expansion at the end of PACKED_PARMS. Returns 0 if the type
15969 deduction succeeds, 1 otherwise. STRICT is the same as in
15970 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15971 call argument list. We'll need to adjust the arguments to make them
15972 types. SUBR tells us if this is from a recursive call to
15973 type_unification_real, or for comparing two template argument
15977 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15978 tree packed_args, unification_kind_t strict,
15979 bool subr, bool explain_p)
15982 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15983 tree pattern = PACK_EXPANSION_PATTERN (parm);
15984 tree pack, packs = NULL_TREE;
15985 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15986 int len = TREE_VEC_LENGTH (packed_args);
15988 /* Determine the parameter packs we will be deducing from the
15989 pattern, and record their current deductions. */
15990 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15991 pack; pack = TREE_CHAIN (pack))
15993 tree parm_pack = TREE_VALUE (pack);
15996 /* Determine the index and level of this parameter pack. */
15997 template_parm_level_and_index (parm_pack, &level, &idx);
15999 /* Keep track of the parameter packs and their corresponding
16001 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
16002 TREE_TYPE (packs) = make_tree_vec (len - start);
16005 /* Loop through all of the arguments that have not yet been
16006 unified and unify each with the pattern. */
16007 for (i = start; i < len; i++)
16010 bool any_explicit = false;
16011 tree arg = TREE_VEC_ELT (packed_args, i);
16013 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
16014 or the element of its argument pack at the current index if
16015 this argument was explicitly specified. */
16016 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16020 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16023 if (TREE_VALUE (pack)
16024 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
16025 && (i < TREE_VEC_LENGTH (pargs)))
16027 any_explicit = true;
16028 arg = TREE_VEC_ELT (pargs, i);
16030 TMPL_ARG (targs, level, idx) = arg;
16033 /* If we had explicit template arguments, substitute them into the
16034 pattern before deduction. */
16037 /* Some arguments might still be unspecified or dependent. */
16039 ++processing_template_decl;
16040 dependent = any_dependent_template_arguments_p (targs);
16042 --processing_template_decl;
16043 parm = tsubst (pattern, targs,
16044 explain_p ? tf_warning_or_error : tf_none,
16047 --processing_template_decl;
16048 if (parm == error_mark_node)
16054 /* Unify the pattern with the current argument. */
16055 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
16056 LOOKUP_IMPLICIT, explain_p))
16059 /* For each parameter pack, collect the deduced value. */
16060 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16063 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16065 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
16066 TMPL_ARG (targs, level, idx);
16070 /* Verify that the results of unification with the parameter packs
16071 produce results consistent with what we've seen before, and make
16072 the deduced argument packs available. */
16073 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16075 tree old_pack = TREE_VALUE (pack);
16076 tree new_args = TREE_TYPE (pack);
16077 int i, len = TREE_VEC_LENGTH (new_args);
16079 bool nondeduced_p = false;
16081 /* By default keep the original deduced argument pack.
16082 If necessary, more specific code is going to update the
16083 resulting deduced argument later down in this function. */
16084 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16085 TMPL_ARG (targs, level, idx) = old_pack;
16087 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16088 actually deduce anything. */
16089 for (i = 0; i < len && !nondeduced_p; ++i)
16090 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16091 nondeduced_p = true;
16095 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16097 /* If we had fewer function args than explicit template args,
16098 just use the explicits. */
16099 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16100 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16101 if (len < explicit_len)
16102 new_args = explicit_args;
16108 /* Build the deduced *_ARGUMENT_PACK. */
16109 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16111 result = make_node (NONTYPE_ARGUMENT_PACK);
16112 TREE_TYPE (result) =
16113 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16114 TREE_CONSTANT (result) = 1;
16117 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16119 SET_ARGUMENT_PACK_ARGS (result, new_args);
16121 /* Note the deduced argument packs for this parameter
16123 TMPL_ARG (targs, level, idx) = result;
16125 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16126 && (ARGUMENT_PACK_ARGS (old_pack)
16127 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16129 /* We only had the explicitly-provided arguments before, but
16130 now we have a complete set of arguments. */
16131 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16133 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16134 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16135 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16139 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16140 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16142 if (!comp_template_args_with_info (old_args, new_args,
16143 &bad_old_arg, &bad_new_arg))
16144 /* Inconsistent unification of this parameter pack. */
16145 return unify_parameter_pack_inconsistent (explain_p,
16151 return unify_success (explain_p);
16154 /* Deduce the value of template parameters. TPARMS is the (innermost)
16155 set of template parameters to a template. TARGS is the bindings
16156 for those template parameters, as determined thus far; TARGS may
16157 include template arguments for outer levels of template parameters
16158 as well. PARM is a parameter to a template function, or a
16159 subcomponent of that parameter; ARG is the corresponding argument.
16160 This function attempts to match PARM with ARG in a manner
16161 consistent with the existing assignments in TARGS. If more values
16162 are deduced, then TARGS is updated.
16164 Returns 0 if the type deduction succeeds, 1 otherwise. The
16165 parameter STRICT is a bitwise or of the following flags:
16168 Require an exact match between PARM and ARG.
16169 UNIFY_ALLOW_MORE_CV_QUAL:
16170 Allow the deduced ARG to be more cv-qualified (by qualification
16171 conversion) than ARG.
16172 UNIFY_ALLOW_LESS_CV_QUAL:
16173 Allow the deduced ARG to be less cv-qualified than ARG.
16174 UNIFY_ALLOW_DERIVED:
16175 Allow the deduced ARG to be a template base class of ARG,
16176 or a pointer to a template base class of the type pointed to by
16178 UNIFY_ALLOW_INTEGER:
16179 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16180 case for more information.
16181 UNIFY_ALLOW_OUTER_LEVEL:
16182 This is the outermost level of a deduction. Used to determine validity
16183 of qualification conversions. A valid qualification conversion must
16184 have const qualified pointers leading up to the inner type which
16185 requires additional CV quals, except at the outer level, where const
16186 is not required [conv.qual]. It would be normal to set this flag in
16187 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16188 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16189 This is the outermost level of a deduction, and PARM can be more CV
16190 qualified at this point.
16191 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16192 This is the outermost level of a deduction, and PARM can be less CV
16193 qualified at this point. */
16196 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16202 int strict_in = strict;
16204 /* I don't think this will do the right thing with respect to types.
16205 But the only case I've seen it in so far has been array bounds, where
16206 signedness is the only information lost, and I think that will be
16208 while (TREE_CODE (parm) == NOP_EXPR)
16209 parm = TREE_OPERAND (parm, 0);
16211 if (arg == error_mark_node)
16212 return unify_invalid (explain_p);
16213 if (arg == unknown_type_node
16214 || arg == init_list_type_node)
16215 /* We can't deduce anything from this, but we might get all the
16216 template args from other function args. */
16217 return unify_success (explain_p);
16219 /* If PARM uses template parameters, then we can't bail out here,
16220 even if ARG == PARM, since we won't record unifications for the
16221 template parameters. We might need them if we're trying to
16222 figure out which of two things is more specialized. */
16223 if (arg == parm && !uses_template_parms (parm))
16224 return unify_success (explain_p);
16226 /* Handle init lists early, so the rest of the function can assume
16227 we're dealing with a type. */
16228 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16232 tree orig_parm = parm;
16234 /* Replace T with std::initializer_list<T> for deduction. */
16235 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16236 && flag_deduce_init_list)
16237 parm = listify (parm);
16239 if (!is_std_init_list (parm))
16240 /* We can only deduce from an initializer list argument if the
16241 parameter is std::initializer_list; otherwise this is a
16242 non-deduced context. */
16243 return unify_success (explain_p);
16245 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16247 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16249 int elt_strict = strict;
16251 if (elt == error_mark_node)
16252 return unify_invalid (explain_p);
16254 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16256 tree type = TREE_TYPE (elt);
16257 /* It should only be possible to get here for a call. */
16258 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16259 elt_strict |= maybe_adjust_types_for_deduction
16260 (DEDUCE_CALL, &elttype, &type, elt);
16264 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16268 /* If the std::initializer_list<T> deduction worked, replace the
16269 deduced A with std::initializer_list<A>. */
16270 if (orig_parm != parm)
16272 idx = TEMPLATE_TYPE_IDX (orig_parm);
16273 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16274 targ = listify (targ);
16275 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16277 return unify_success (explain_p);
16280 /* Immediately reject some pairs that won't unify because of
16281 cv-qualification mismatches. */
16282 if (TREE_CODE (arg) == TREE_CODE (parm)
16284 /* It is the elements of the array which hold the cv quals of an array
16285 type, and the elements might be template type parms. We'll check
16286 when we recurse. */
16287 && TREE_CODE (arg) != ARRAY_TYPE
16288 /* We check the cv-qualifiers when unifying with template type
16289 parameters below. We want to allow ARG `const T' to unify with
16290 PARM `T' for example, when computing which of two templates
16291 is more specialized, for example. */
16292 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16293 && !check_cv_quals_for_unify (strict_in, arg, parm))
16294 return unify_cv_qual_mismatch (explain_p, parm, arg);
16296 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16297 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16298 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16299 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16300 strict &= ~UNIFY_ALLOW_DERIVED;
16301 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16302 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16304 switch (TREE_CODE (parm))
16306 case TYPENAME_TYPE:
16308 case UNBOUND_CLASS_TEMPLATE:
16309 /* In a type which contains a nested-name-specifier, template
16310 argument values cannot be deduced for template parameters used
16311 within the nested-name-specifier. */
16312 return unify_success (explain_p);
16314 case TEMPLATE_TYPE_PARM:
16315 case TEMPLATE_TEMPLATE_PARM:
16316 case BOUND_TEMPLATE_TEMPLATE_PARM:
16317 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16318 if (tparm == error_mark_node)
16319 return unify_invalid (explain_p);
16321 if (TEMPLATE_TYPE_LEVEL (parm)
16322 != template_decl_level (tparm))
16323 /* The PARM is not one we're trying to unify. Just check
16324 to see if it matches ARG. */
16326 if (TREE_CODE (arg) == TREE_CODE (parm)
16327 && same_type_p (parm, arg))
16328 return unify_success (explain_p);
16330 return unify_type_mismatch (explain_p, parm, arg);
16332 idx = TEMPLATE_TYPE_IDX (parm);
16333 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16334 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16335 if (tparm == error_mark_node)
16336 return unify_invalid (explain_p);
16338 /* Check for mixed types and values. */
16339 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16340 && TREE_CODE (tparm) != TYPE_DECL)
16341 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16342 && TREE_CODE (tparm) != TEMPLATE_DECL))
16343 gcc_unreachable ();
16345 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16347 /* ARG must be constructed from a template class or a template
16348 template parameter. */
16349 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16350 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16351 return unify_template_deduction_failure (explain_p, parm, arg);
16354 tree parmvec = TYPE_TI_ARGS (parm);
16355 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16356 tree full_argvec = add_to_template_args (targs, argvec);
16358 = DECL_INNERMOST_TEMPLATE_PARMS
16359 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16361 int parm_variadic_p = 0;
16363 /* The resolution to DR150 makes clear that default
16364 arguments for an N-argument may not be used to bind T
16365 to a template template parameter with fewer than N
16366 parameters. It is not safe to permit the binding of
16367 default arguments as an extension, as that may change
16368 the meaning of a conforming program. Consider:
16370 struct Dense { static const unsigned int dim = 1; };
16372 template <template <typename> class View,
16374 void operator+(float, View<Block> const&);
16376 template <typename Block,
16377 unsigned int Dim = Block::dim>
16378 struct Lvalue_proxy { operator float() const; };
16382 Lvalue_proxy<Dense> p;
16387 Here, if Lvalue_proxy is permitted to bind to View, then
16388 the global operator+ will be used; if they are not, the
16389 Lvalue_proxy will be converted to float. */
16390 if (coerce_template_parms (parm_parms,
16392 TYPE_TI_TEMPLATE (parm),
16394 ? tf_warning_or_error
16396 /*require_all_args=*/true,
16397 /*use_default_args=*/false)
16398 == error_mark_node)
16401 /* Deduce arguments T, i from TT<T> or TT<i>.
16402 We check each element of PARMVEC and ARGVEC individually
16403 rather than the whole TREE_VEC since they can have
16404 different number of elements. */
16406 parmvec = expand_template_argument_pack (parmvec);
16407 argvec = expand_template_argument_pack (argvec);
16409 len = TREE_VEC_LENGTH (parmvec);
16411 /* Check if the parameters end in a pack, making them
16414 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16415 parm_variadic_p = 1;
16417 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16418 return unify_too_few_arguments (explain_p,
16419 TREE_VEC_LENGTH (argvec), len);
16421 for (i = 0; i < len - parm_variadic_p; ++i)
16423 RECUR_AND_CHECK_FAILURE (tparms, targs,
16424 TREE_VEC_ELT (parmvec, i),
16425 TREE_VEC_ELT (argvec, i),
16426 UNIFY_ALLOW_NONE, explain_p);
16429 if (parm_variadic_p
16430 && unify_pack_expansion (tparms, targs,
16433 /*subr=*/true, explain_p))
16436 arg = TYPE_TI_TEMPLATE (arg);
16438 /* Fall through to deduce template name. */
16441 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16442 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16444 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16446 /* Simple cases: Value already set, does match or doesn't. */
16447 if (targ != NULL_TREE && template_args_equal (targ, arg))
16448 return unify_success (explain_p);
16450 return unify_inconsistency (explain_p, parm, targ, arg);
16454 /* If PARM is `const T' and ARG is only `int', we don't have
16455 a match unless we are allowing additional qualification.
16456 If ARG is `const int' and PARM is just `T' that's OK;
16457 that binds `const int' to `T'. */
16458 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16460 return unify_cv_qual_mismatch (explain_p, parm, arg);
16462 /* Consider the case where ARG is `const volatile int' and
16463 PARM is `const T'. Then, T should be `volatile int'. */
16464 arg = cp_build_qualified_type_real
16465 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16466 if (arg == error_mark_node)
16467 return unify_invalid (explain_p);
16469 /* Simple cases: Value already set, does match or doesn't. */
16470 if (targ != NULL_TREE && same_type_p (targ, arg))
16471 return unify_success (explain_p);
16473 return unify_inconsistency (explain_p, parm, targ, arg);
16475 /* Make sure that ARG is not a variable-sized array. (Note
16476 that were talking about variable-sized arrays (like
16477 `int[n]'), rather than arrays of unknown size (like
16478 `int[]').) We'll get very confused by such a type since
16479 the bound of the array is not constant, and therefore
16480 not mangleable. Besides, such types are not allowed in
16481 ISO C++, so we can do as we please here. We do allow
16482 them for 'auto' deduction, since that isn't ABI-exposed. */
16483 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16484 return unify_vla_arg (explain_p, arg);
16486 /* Strip typedefs as in convert_template_argument. */
16487 arg = canonicalize_type_argument (arg, tf_none);
16490 /* If ARG is a parameter pack or an expansion, we cannot unify
16491 against it unless PARM is also a parameter pack. */
16492 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16493 && !template_parameter_pack_p (parm))
16494 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16496 /* If the argument deduction results is a METHOD_TYPE,
16497 then there is a problem.
16498 METHOD_TYPE doesn't map to any real C++ type the result of
16499 the deduction can not be of that type. */
16500 if (TREE_CODE (arg) == METHOD_TYPE)
16501 return unify_method_type_error (explain_p, arg);
16503 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16504 return unify_success (explain_p);
16506 case TEMPLATE_PARM_INDEX:
16507 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16508 if (tparm == error_mark_node)
16509 return unify_invalid (explain_p);
16511 if (TEMPLATE_PARM_LEVEL (parm)
16512 != template_decl_level (tparm))
16514 /* The PARM is not one we're trying to unify. Just check
16515 to see if it matches ARG. */
16516 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16517 && cp_tree_equal (parm, arg));
16519 unify_expression_unequal (explain_p, parm, arg);
16523 idx = TEMPLATE_PARM_IDX (parm);
16524 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16528 int x = !cp_tree_equal (targ, arg);
16530 unify_inconsistency (explain_p, parm, targ, arg);
16534 /* [temp.deduct.type] If, in the declaration of a function template
16535 with a non-type template-parameter, the non-type
16536 template-parameter is used in an expression in the function
16537 parameter-list and, if the corresponding template-argument is
16538 deduced, the template-argument type shall match the type of the
16539 template-parameter exactly, except that a template-argument
16540 deduced from an array bound may be of any integral type.
16541 The non-type parameter might use already deduced type parameters. */
16542 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16543 if (!TREE_TYPE (arg))
16544 /* Template-parameter dependent expression. Just accept it for now.
16545 It will later be processed in convert_template_argument. */
16547 else if (same_type_p (TREE_TYPE (arg), tparm))
16549 else if ((strict & UNIFY_ALLOW_INTEGER)
16550 && (TREE_CODE (tparm) == INTEGER_TYPE
16551 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16552 /* Convert the ARG to the type of PARM; the deduced non-type
16553 template argument must exactly match the types of the
16554 corresponding parameter. */
16555 arg = fold (build_nop (tparm, arg));
16556 else if (uses_template_parms (tparm))
16557 /* We haven't deduced the type of this parameter yet. Try again
16559 return unify_success (explain_p);
16561 return unify_type_mismatch (explain_p, tparm, arg);
16563 /* If ARG is a parameter pack or an expansion, we cannot unify
16564 against it unless PARM is also a parameter pack. */
16565 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16566 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16567 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16569 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16570 return unify_success (explain_p);
16574 /* A pointer-to-member constant can be unified only with
16575 another constant. */
16576 if (TREE_CODE (arg) != PTRMEM_CST)
16577 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16579 /* Just unify the class member. It would be useless (and possibly
16580 wrong, depending on the strict flags) to unify also
16581 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16582 arg refer to the same variable, even if through different
16583 classes. For instance:
16585 struct A { int x; };
16588 Unification of &A::x and &B::x must succeed. */
16589 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16590 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16595 if (TREE_CODE (arg) != POINTER_TYPE)
16596 return unify_type_mismatch (explain_p, parm, arg);
16598 /* [temp.deduct.call]
16600 A can be another pointer or pointer to member type that can
16601 be converted to the deduced A via a qualification
16602 conversion (_conv.qual_).
16604 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16605 This will allow for additional cv-qualification of the
16606 pointed-to types if appropriate. */
16608 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16609 /* The derived-to-base conversion only persists through one
16610 level of pointers. */
16611 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16613 return unify (tparms, targs, TREE_TYPE (parm),
16614 TREE_TYPE (arg), strict, explain_p);
16617 case REFERENCE_TYPE:
16618 if (TREE_CODE (arg) != REFERENCE_TYPE)
16619 return unify_type_mismatch (explain_p, parm, arg);
16620 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16621 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16624 if (TREE_CODE (arg) != ARRAY_TYPE)
16625 return unify_type_mismatch (explain_p, parm, arg);
16626 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16627 != (TYPE_DOMAIN (arg) == NULL_TREE))
16628 return unify_type_mismatch (explain_p, parm, arg);
16629 if (TYPE_DOMAIN (parm) != NULL_TREE)
16636 /* Our representation of array types uses "N - 1" as the
16637 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16638 not an integer constant. We cannot unify arbitrarily
16639 complex expressions, so we eliminate the MINUS_EXPRs
16641 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16642 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16645 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16646 parm_max = TREE_OPERAND (parm_max, 0);
16648 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16649 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16652 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16653 trying to unify the type of a variable with the type
16654 of a template parameter. For example:
16656 template <unsigned int N>
16657 void f (char (&) [N]);
16664 Here, the type of the ARG will be "int [g(i)]", and
16665 may be a SAVE_EXPR, etc. */
16666 if (TREE_CODE (arg_max) != MINUS_EXPR)
16667 return unify_vla_arg (explain_p, arg);
16668 arg_max = TREE_OPERAND (arg_max, 0);
16671 /* If only one of the bounds used a MINUS_EXPR, compensate
16672 by adding one to the other bound. */
16673 if (parm_cst && !arg_cst)
16674 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16678 else if (arg_cst && !parm_cst)
16679 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16684 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16685 UNIFY_ALLOW_INTEGER, explain_p);
16687 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16688 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16695 case ENUMERAL_TYPE:
16698 if (TREE_CODE (arg) != TREE_CODE (parm))
16699 return unify_type_mismatch (explain_p, parm, arg);
16701 /* We have already checked cv-qualification at the top of the
16703 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16704 return unify_type_mismatch (explain_p, parm, arg);
16706 /* As far as unification is concerned, this wins. Later checks
16707 will invalidate it if necessary. */
16708 return unify_success (explain_p);
16710 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16711 /* Type INTEGER_CST can come from ordinary constant template args. */
16713 while (TREE_CODE (arg) == NOP_EXPR)
16714 arg = TREE_OPERAND (arg, 0);
16716 if (TREE_CODE (arg) != INTEGER_CST)
16717 return unify_template_argument_mismatch (explain_p, parm, arg);
16718 return (tree_int_cst_equal (parm, arg)
16719 ? unify_success (explain_p)
16720 : unify_template_argument_mismatch (explain_p, parm, arg));
16724 int i, len, argslen;
16725 int parm_variadic_p = 0;
16727 if (TREE_CODE (arg) != TREE_VEC)
16728 return unify_template_argument_mismatch (explain_p, parm, arg);
16730 len = TREE_VEC_LENGTH (parm);
16731 argslen = TREE_VEC_LENGTH (arg);
16733 /* Check for pack expansions in the parameters. */
16734 for (i = 0; i < len; ++i)
16736 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16739 /* We can unify against something with a trailing
16741 parm_variadic_p = 1;
16743 /* [temp.deduct.type]/9: If the template argument list of
16744 P contains a pack expansion that is not the last
16745 template argument, the entire template argument list
16746 is a non-deduced context. */
16747 return unify_success (explain_p);
16751 /* If we don't have enough arguments to satisfy the parameters
16752 (not counting the pack expression at the end), or we have
16753 too many arguments for a parameter list that doesn't end in
16754 a pack expression, we can't unify. */
16755 if (parm_variadic_p
16756 ? argslen < len - parm_variadic_p
16758 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16760 /* Unify all of the parameters that precede the (optional)
16761 pack expression. */
16762 for (i = 0; i < len - parm_variadic_p; ++i)
16764 RECUR_AND_CHECK_FAILURE (tparms, targs,
16765 TREE_VEC_ELT (parm, i),
16766 TREE_VEC_ELT (arg, i),
16767 UNIFY_ALLOW_NONE, explain_p);
16769 if (parm_variadic_p)
16770 return unify_pack_expansion (tparms, targs, parm, arg,
16772 /*subr=*/true, explain_p);
16773 return unify_success (explain_p);
16778 if (TREE_CODE (arg) != TREE_CODE (parm))
16779 return unify_type_mismatch (explain_p, parm, arg);
16781 if (TYPE_PTRMEMFUNC_P (parm))
16783 if (!TYPE_PTRMEMFUNC_P (arg))
16784 return unify_type_mismatch (explain_p, parm, arg);
16786 return unify (tparms, targs,
16787 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16788 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16789 strict, explain_p);
16792 if (CLASSTYPE_TEMPLATE_INFO (parm))
16794 tree t = NULL_TREE;
16796 if (strict_in & UNIFY_ALLOW_DERIVED)
16798 /* First, we try to unify the PARM and ARG directly. */
16799 t = try_class_unification (tparms, targs,
16800 parm, arg, explain_p);
16804 /* Fallback to the special case allowed in
16805 [temp.deduct.call]:
16807 If P is a class, and P has the form
16808 template-id, then A can be a derived class of
16809 the deduced A. Likewise, if P is a pointer to
16810 a class of the form template-id, A can be a
16811 pointer to a derived class pointed to by the
16813 enum template_base_result r;
16814 r = get_template_base (tparms, targs, parm, arg,
16818 return unify_no_common_base (explain_p, r, parm, arg);
16821 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16822 && (CLASSTYPE_TI_TEMPLATE (parm)
16823 == CLASSTYPE_TI_TEMPLATE (arg)))
16824 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16825 Then, we should unify `int' and `U'. */
16828 /* There's no chance of unification succeeding. */
16829 return unify_type_mismatch (explain_p, parm, arg);
16831 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16832 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16834 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16835 return unify_type_mismatch (explain_p, parm, arg);
16836 return unify_success (explain_p);
16839 case FUNCTION_TYPE:
16841 unsigned int nargs;
16846 if (TREE_CODE (arg) != TREE_CODE (parm))
16847 return unify_type_mismatch (explain_p, parm, arg);
16849 /* CV qualifications for methods can never be deduced, they must
16850 match exactly. We need to check them explicitly here,
16851 because type_unification_real treats them as any other
16852 cv-qualified parameter. */
16853 if (TREE_CODE (parm) == METHOD_TYPE
16854 && (!check_cv_quals_for_unify
16856 class_of_this_parm (arg),
16857 class_of_this_parm (parm))))
16858 return unify_cv_qual_mismatch (explain_p, parm, arg);
16860 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16861 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16863 nargs = list_length (TYPE_ARG_TYPES (arg));
16864 args = XALLOCAVEC (tree, nargs);
16865 for (a = TYPE_ARG_TYPES (arg), i = 0;
16866 a != NULL_TREE && a != void_list_node;
16867 a = TREE_CHAIN (a), ++i)
16868 args[i] = TREE_VALUE (a);
16871 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16872 args, nargs, 1, DEDUCE_EXACT,
16873 LOOKUP_NORMAL, explain_p);
16877 /* Unify a pointer to member with a pointer to member function, which
16878 deduces the type of the member as a function type. */
16879 if (TYPE_PTRMEMFUNC_P (arg))
16884 /* Check top-level cv qualifiers */
16885 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16886 return unify_cv_qual_mismatch (explain_p, parm, arg);
16888 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16889 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16890 UNIFY_ALLOW_NONE, explain_p);
16892 /* Determine the type of the function we are unifying against. */
16893 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16895 build_function_type (TREE_TYPE (method_type),
16896 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16898 /* Extract the cv-qualifiers of the member function from the
16899 implicit object parameter and place them on the function
16900 type to be restored later. */
16901 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16902 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16905 if (TREE_CODE (arg) != OFFSET_TYPE)
16906 return unify_type_mismatch (explain_p, parm, arg);
16907 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16908 TYPE_OFFSET_BASETYPE (arg),
16909 UNIFY_ALLOW_NONE, explain_p);
16910 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16911 strict, explain_p);
16914 if (DECL_TEMPLATE_PARM_P (parm))
16915 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16916 if (arg != integral_constant_value (parm))
16917 return unify_template_argument_mismatch (explain_p, parm, arg);
16918 return unify_success (explain_p);
16921 case TEMPLATE_DECL:
16922 /* Matched cases are handled by the ARG == PARM test above. */
16923 return unify_template_argument_mismatch (explain_p, parm, arg);
16926 /* A non-type template parameter that is a variable should be a
16927 an integral constant, in which case, it whould have been
16928 folded into its (constant) value. So we should not be getting
16929 a variable here. */
16930 gcc_unreachable ();
16932 case TYPE_ARGUMENT_PACK:
16933 case NONTYPE_ARGUMENT_PACK:
16934 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16935 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16938 case DECLTYPE_TYPE:
16939 case UNDERLYING_TYPE:
16940 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16941 or UNDERLYING_TYPE nodes. */
16942 return unify_success (explain_p);
16945 /* Unification fails if we hit an error node. */
16946 return unify_invalid (explain_p);
16949 /* An unresolved overload is a nondeduced context. */
16950 if (is_overloaded_fn (parm) || type_unknown_p (parm))
16951 return unify_success (explain_p);
16952 gcc_assert (EXPR_P (parm));
16954 /* We must be looking at an expression. This can happen with
16958 void foo(S<I>, S<I + 2>);
16960 This is a "nondeduced context":
16964 The nondeduced contexts are:
16966 --A type that is a template-id in which one or more of
16967 the template-arguments is an expression that references
16968 a template-parameter.
16970 In these cases, we assume deduction succeeded, but don't
16971 actually infer any unifications. */
16973 if (!uses_template_parms (parm)
16974 && !template_args_equal (parm, arg))
16975 return unify_expression_unequal (explain_p, parm, arg);
16977 return unify_success (explain_p);
16980 #undef RECUR_AND_CHECK_FAILURE
16982 /* Note that DECL can be defined in this translation unit, if
16986 mark_definable (tree decl)
16989 DECL_NOT_REALLY_EXTERN (decl) = 1;
16990 FOR_EACH_CLONE (clone, decl)
16991 DECL_NOT_REALLY_EXTERN (clone) = 1;
16994 /* Called if RESULT is explicitly instantiated, or is a member of an
16995 explicitly instantiated class. */
16998 mark_decl_instantiated (tree result, int extern_p)
17000 SET_DECL_EXPLICIT_INSTANTIATION (result);
17002 /* If this entity has already been written out, it's too late to
17003 make any modifications. */
17004 if (TREE_ASM_WRITTEN (result))
17007 if (TREE_CODE (result) != FUNCTION_DECL)
17008 /* The TREE_PUBLIC flag for function declarations will have been
17009 set correctly by tsubst. */
17010 TREE_PUBLIC (result) = 1;
17012 /* This might have been set by an earlier implicit instantiation. */
17013 DECL_COMDAT (result) = 0;
17016 DECL_NOT_REALLY_EXTERN (result) = 0;
17019 mark_definable (result);
17020 /* Always make artificials weak. */
17021 if (DECL_ARTIFICIAL (result) && flag_weak)
17022 comdat_linkage (result);
17023 /* For WIN32 we also want to put explicit instantiations in
17024 linkonce sections. */
17025 else if (TREE_PUBLIC (result))
17026 maybe_make_one_only (result);
17029 /* If EXTERN_P, then this function will not be emitted -- unless
17030 followed by an explicit instantiation, at which point its linkage
17031 will be adjusted. If !EXTERN_P, then this function will be
17032 emitted here. In neither circumstance do we want
17033 import_export_decl to adjust the linkage. */
17034 DECL_INTERFACE_KNOWN (result) = 1;
17037 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
17038 important template arguments. If any are missing, we check whether
17039 they're important by using error_mark_node for substituting into any
17040 args that were used for partial ordering (the ones between ARGS and END)
17041 and seeing if it bubbles up. */
17044 check_undeduced_parms (tree targs, tree args, tree end)
17046 bool found = false;
17048 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
17049 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
17052 TREE_VEC_ELT (targs, i) = error_mark_node;
17056 for (; args != end; args = TREE_CHAIN (args))
17058 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
17059 if (substed == error_mark_node)
17066 /* Given two function templates PAT1 and PAT2, return:
17068 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
17069 -1 if PAT2 is more specialized than PAT1.
17070 0 if neither is more specialized.
17072 LEN indicates the number of parameters we should consider
17073 (defaulted parameters should not be considered).
17075 The 1998 std underspecified function template partial ordering, and
17076 DR214 addresses the issue. We take pairs of arguments, one from
17077 each of the templates, and deduce them against each other. One of
17078 the templates will be more specialized if all the *other*
17079 template's arguments deduce against its arguments and at least one
17080 of its arguments *does* *not* deduce against the other template's
17081 corresponding argument. Deduction is done as for class templates.
17082 The arguments used in deduction have reference and top level cv
17083 qualifiers removed. Iff both arguments were originally reference
17084 types *and* deduction succeeds in both directions, the template
17085 with the more cv-qualified argument wins for that pairing (if
17086 neither is more cv-qualified, they both are equal). Unlike regular
17087 deduction, after all the arguments have been deduced in this way,
17088 we do *not* verify the deduced template argument values can be
17089 substituted into non-deduced contexts.
17091 The logic can be a bit confusing here, because we look at deduce1 and
17092 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17093 can find template arguments for pat1 to make arg1 look like arg2, that
17094 means that arg2 is at least as specialized as arg1. */
17097 more_specialized_fn (tree pat1, tree pat2, int len)
17099 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17100 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17101 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17102 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17103 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17104 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17105 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17106 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17107 tree origs1, origs2;
17108 bool lose1 = false;
17109 bool lose2 = false;
17111 /* Remove the this parameter from non-static member functions. If
17112 one is a non-static member function and the other is not a static
17113 member function, remove the first parameter from that function
17114 also. This situation occurs for operator functions where we
17115 locate both a member function (with this pointer) and non-member
17116 operator (with explicit first operand). */
17117 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17119 len--; /* LEN is the number of significant arguments for DECL1 */
17120 args1 = TREE_CHAIN (args1);
17121 if (!DECL_STATIC_FUNCTION_P (decl2))
17122 args2 = TREE_CHAIN (args2);
17124 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17126 args2 = TREE_CHAIN (args2);
17127 if (!DECL_STATIC_FUNCTION_P (decl1))
17130 args1 = TREE_CHAIN (args1);
17134 /* If only one is a conversion operator, they are unordered. */
17135 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17138 /* Consider the return type for a conversion function */
17139 if (DECL_CONV_FN_P (decl1))
17141 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17142 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17146 processing_template_decl++;
17152 /* Stop when an ellipsis is seen. */
17153 && args1 != NULL_TREE && args2 != NULL_TREE)
17155 tree arg1 = TREE_VALUE (args1);
17156 tree arg2 = TREE_VALUE (args2);
17157 int deduce1, deduce2;
17161 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17162 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17164 /* When both arguments are pack expansions, we need only
17165 unify the patterns themselves. */
17166 arg1 = PACK_EXPANSION_PATTERN (arg1);
17167 arg2 = PACK_EXPANSION_PATTERN (arg2);
17169 /* This is the last comparison we need to do. */
17173 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17175 arg1 = TREE_TYPE (arg1);
17176 quals1 = cp_type_quals (arg1);
17179 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17181 arg2 = TREE_TYPE (arg2);
17182 quals2 = cp_type_quals (arg2);
17185 if ((quals1 < 0) != (quals2 < 0))
17187 /* Only of the args is a reference, see if we should apply
17188 array/function pointer decay to it. This is not part of
17189 DR214, but is, IMHO, consistent with the deduction rules
17190 for the function call itself, and with our earlier
17191 implementation of the underspecified partial ordering
17192 rules. (nathan). */
17195 switch (TREE_CODE (arg1))
17198 arg1 = TREE_TYPE (arg1);
17200 case FUNCTION_TYPE:
17201 arg1 = build_pointer_type (arg1);
17210 switch (TREE_CODE (arg2))
17213 arg2 = TREE_TYPE (arg2);
17215 case FUNCTION_TYPE:
17216 arg2 = build_pointer_type (arg2);
17225 arg1 = TYPE_MAIN_VARIANT (arg1);
17226 arg2 = TYPE_MAIN_VARIANT (arg2);
17228 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17230 int i, len2 = list_length (args2);
17231 tree parmvec = make_tree_vec (1);
17232 tree argvec = make_tree_vec (len2);
17235 /* Setup the parameter vector, which contains only ARG1. */
17236 TREE_VEC_ELT (parmvec, 0) = arg1;
17238 /* Setup the argument vector, which contains the remaining
17240 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17241 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17243 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17244 argvec, DEDUCE_EXACT,
17245 /*subr=*/true, /*explain_p=*/false)
17248 /* We cannot deduce in the other direction, because ARG1 is
17249 a pack expansion but ARG2 is not. */
17252 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17254 int i, len1 = list_length (args1);
17255 tree parmvec = make_tree_vec (1);
17256 tree argvec = make_tree_vec (len1);
17259 /* Setup the parameter vector, which contains only ARG1. */
17260 TREE_VEC_ELT (parmvec, 0) = arg2;
17262 /* Setup the argument vector, which contains the remaining
17264 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17265 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17267 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17268 argvec, DEDUCE_EXACT,
17269 /*subr=*/true, /*explain_p=*/false)
17272 /* We cannot deduce in the other direction, because ARG2 is
17273 a pack expansion but ARG1 is not.*/
17279 /* The normal case, where neither argument is a pack
17281 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17282 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17284 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17285 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17289 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17290 arg2, then arg2 is not as specialized as arg1. */
17296 /* "If, for a given type, deduction succeeds in both directions
17297 (i.e., the types are identical after the transformations above)
17298 and if the type from the argument template is more cv-qualified
17299 than the type from the parameter template (as described above)
17300 that type is considered to be more specialized than the other. If
17301 neither type is more cv-qualified than the other then neither type
17302 is more specialized than the other." */
17304 if (deduce1 && deduce2
17305 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17307 if ((quals1 & quals2) == quals2)
17309 if ((quals1 & quals2) == quals1)
17313 if (lose1 && lose2)
17314 /* We've failed to deduce something in either direction.
17315 These must be unordered. */
17318 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17319 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17320 /* We have already processed all of the arguments in our
17321 handing of the pack expansion type. */
17324 args1 = TREE_CHAIN (args1);
17325 args2 = TREE_CHAIN (args2);
17328 /* "In most cases, all template parameters must have values in order for
17329 deduction to succeed, but for partial ordering purposes a template
17330 parameter may remain without a value provided it is not used in the
17331 types being used for partial ordering."
17333 Thus, if we are missing any of the targs1 we need to substitute into
17334 origs1, then pat2 is not as specialized as pat1. This can happen when
17335 there is a nondeduced context. */
17336 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17338 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17341 processing_template_decl--;
17343 /* All things being equal, if the next argument is a pack expansion
17344 for one function but not for the other, prefer the
17345 non-variadic function. FIXME this is bogus; see c++/41958. */
17347 && args1 && TREE_VALUE (args1)
17348 && args2 && TREE_VALUE (args2))
17350 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17351 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17354 if (lose1 == lose2)
17362 /* Determine which of two partial specializations is more specialized.
17364 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17365 to the first partial specialization. The TREE_VALUE is the
17366 innermost set of template parameters for the partial
17367 specialization. PAT2 is similar, but for the second template.
17369 Return 1 if the first partial specialization is more specialized;
17370 -1 if the second is more specialized; 0 if neither is more
17373 See [temp.class.order] for information about determining which of
17374 two templates is more specialized. */
17377 more_specialized_class (tree pat1, tree pat2)
17382 bool any_deductions = false;
17384 tmpl1 = TREE_TYPE (pat1);
17385 tmpl2 = TREE_TYPE (pat2);
17387 /* Just like what happens for functions, if we are ordering between
17388 different class template specializations, we may encounter dependent
17389 types in the arguments, and we need our dependency check functions
17390 to behave correctly. */
17391 ++processing_template_decl;
17392 targs = get_class_bindings (TREE_VALUE (pat1),
17393 CLASSTYPE_TI_ARGS (tmpl1),
17394 CLASSTYPE_TI_ARGS (tmpl2));
17398 any_deductions = true;
17401 targs = get_class_bindings (TREE_VALUE (pat2),
17402 CLASSTYPE_TI_ARGS (tmpl2),
17403 CLASSTYPE_TI_ARGS (tmpl1));
17407 any_deductions = true;
17409 --processing_template_decl;
17411 /* In the case of a tie where at least one of the class templates
17412 has a parameter pack at the end, the template with the most
17413 non-packed parameters wins. */
17416 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17417 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17419 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17420 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17421 int len1 = TREE_VEC_LENGTH (args1);
17422 int len2 = TREE_VEC_LENGTH (args2);
17424 /* We don't count the pack expansion at the end. */
17425 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17427 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17432 else if (len1 < len2)
17439 /* Return the template arguments that will produce the function signature
17440 DECL from the function template FN, with the explicit template
17441 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17442 also match. Return NULL_TREE if no satisfactory arguments could be
17446 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17448 int ntparms = DECL_NTPARMS (fn);
17449 tree targs = make_tree_vec (ntparms);
17451 tree decl_arg_types;
17453 unsigned int nargs, ix;
17456 /* Substitute the explicit template arguments into the type of DECL.
17457 The call to fn_type_unification will handle substitution into the
17459 decl_type = TREE_TYPE (decl);
17460 if (explicit_args && uses_template_parms (decl_type))
17463 tree converted_args;
17465 if (DECL_TEMPLATE_INFO (decl))
17466 tmpl = DECL_TI_TEMPLATE (decl);
17468 /* We can get here for some invalid specializations. */
17472 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17473 explicit_args, NULL_TREE,
17475 /*require_all_args=*/false,
17476 /*use_default_args=*/false);
17477 if (converted_args == error_mark_node)
17480 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17481 if (decl_type == error_mark_node)
17485 /* Never do unification on the 'this' parameter. */
17486 decl_arg_types = skip_artificial_parms_for (decl,
17487 TYPE_ARG_TYPES (decl_type));
17489 nargs = list_length (decl_arg_types);
17490 args = XALLOCAVEC (tree, nargs);
17491 for (arg = decl_arg_types, ix = 0;
17492 arg != NULL_TREE && arg != void_list_node;
17493 arg = TREE_CHAIN (arg), ++ix)
17494 args[ix] = TREE_VALUE (arg);
17496 if (fn_type_unification (fn, explicit_args, targs,
17498 (check_rettype || DECL_CONV_FN_P (fn)
17499 ? TREE_TYPE (decl_type) : NULL_TREE),
17500 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17506 /* Return the innermost template arguments that, when applied to a
17507 template specialization whose innermost template parameters are
17508 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17511 For example, suppose we have:
17513 template <class T, class U> struct S {};
17514 template <class T> struct S<T*, int> {};
17516 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17517 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17518 int}. The resulting vector will be {double}, indicating that `T'
17519 is bound to `double'. */
17522 get_class_bindings (tree tparms, tree spec_args, tree args)
17524 int i, ntparms = TREE_VEC_LENGTH (tparms);
17526 tree innermost_deduced_args;
17528 innermost_deduced_args = make_tree_vec (ntparms);
17529 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17531 deduced_args = copy_node (args);
17532 SET_TMPL_ARGS_LEVEL (deduced_args,
17533 TMPL_ARGS_DEPTH (deduced_args),
17534 innermost_deduced_args);
17537 deduced_args = innermost_deduced_args;
17539 if (unify (tparms, deduced_args,
17540 INNERMOST_TEMPLATE_ARGS (spec_args),
17541 INNERMOST_TEMPLATE_ARGS (args),
17542 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17545 for (i = 0; i < ntparms; ++i)
17546 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17549 /* Verify that nondeduced template arguments agree with the type
17550 obtained from argument deduction.
17554 struct A { typedef int X; };
17555 template <class T, class U> struct C {};
17556 template <class T> struct C<T, typename T::X> {};
17558 Then with the instantiation `C<A, int>', we can deduce that
17559 `T' is `A' but unify () does not check whether `typename T::X'
17561 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17562 if (spec_args == error_mark_node
17563 /* We only need to check the innermost arguments; the other
17564 arguments will always agree. */
17565 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17566 INNERMOST_TEMPLATE_ARGS (args)))
17569 /* Now that we have bindings for all of the template arguments,
17570 ensure that the arguments deduced for the template template
17571 parameters have compatible template parameter lists. See the use
17572 of template_template_parm_bindings_ok_p in fn_type_unification
17573 for more information. */
17574 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17577 return deduced_args;
17580 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17581 Return the TREE_LIST node with the most specialized template, if
17582 any. If there is no most specialized template, the error_mark_node
17585 Note that this function does not look at, or modify, the
17586 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17587 returned is one of the elements of INSTANTIATIONS, callers may
17588 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17589 and retrieve it from the value returned. */
17592 most_specialized_instantiation (tree templates)
17596 ++processing_template_decl;
17599 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17603 if (get_bindings (TREE_VALUE (champ),
17604 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17605 NULL_TREE, /*check_ret=*/true))
17608 if (get_bindings (TREE_VALUE (fn),
17609 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17610 NULL_TREE, /*check_ret=*/true))
17617 /* Equally specialized, move to next function. If there
17618 is no next function, nothing's most specialized. */
17619 fn = TREE_CHAIN (fn);
17627 /* Now verify that champ is better than everything earlier in the
17628 instantiation list. */
17629 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17630 if (get_bindings (TREE_VALUE (champ),
17631 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17632 NULL_TREE, /*check_ret=*/true)
17633 || !get_bindings (TREE_VALUE (fn),
17634 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17635 NULL_TREE, /*check_ret=*/true))
17641 processing_template_decl--;
17644 return error_mark_node;
17649 /* If DECL is a specialization of some template, return the most
17650 general such template. Otherwise, returns NULL_TREE.
17652 For example, given:
17654 template <class T> struct S { template <class U> void f(U); };
17656 if TMPL is `template <class U> void S<int>::f(U)' this will return
17657 the full template. This function will not trace past partial
17658 specializations, however. For example, given in addition:
17660 template <class T> struct S<T*> { template <class U> void f(U); };
17662 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17663 `template <class T> template <class U> S<T*>::f(U)'. */
17666 most_general_template (tree decl)
17668 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17669 an immediate specialization. */
17670 if (TREE_CODE (decl) == FUNCTION_DECL)
17672 if (DECL_TEMPLATE_INFO (decl)) {
17673 decl = DECL_TI_TEMPLATE (decl);
17675 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17676 template friend. */
17677 if (TREE_CODE (decl) != TEMPLATE_DECL)
17683 /* Look for more and more general templates. */
17684 while (DECL_TEMPLATE_INFO (decl))
17686 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17687 (See cp-tree.h for details.) */
17688 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17691 if (CLASS_TYPE_P (TREE_TYPE (decl))
17692 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17695 /* Stop if we run into an explicitly specialized class template. */
17696 if (!DECL_NAMESPACE_SCOPE_P (decl)
17697 && DECL_CONTEXT (decl)
17698 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17701 decl = DECL_TI_TEMPLATE (decl);
17707 /* Return the most specialized of the class template partial
17708 specializations of TMPL which can produce TYPE, a specialization of
17709 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17710 a _TYPE node corresponding to the partial specialization, while the
17711 TREE_PURPOSE is the set of template arguments that must be
17712 substituted into the TREE_TYPE in order to generate TYPE.
17714 If the choice of partial specialization is ambiguous, a diagnostic
17715 is issued, and the error_mark_node is returned. If there are no
17716 partial specializations of TMPL matching TYPE, then NULL_TREE is
17720 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17722 tree list = NULL_TREE;
17728 tree outer_args = NULL_TREE;
17730 tmpl = most_general_template (tmpl);
17731 args = CLASSTYPE_TI_ARGS (type);
17733 /* For determining which partial specialization to use, only the
17734 innermost args are interesting. */
17735 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17737 outer_args = strip_innermost_template_args (args, 1);
17738 args = INNERMOST_TEMPLATE_ARGS (args);
17741 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17743 tree partial_spec_args;
17745 tree parms = TREE_VALUE (t);
17747 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17749 ++processing_template_decl;
17755 /* Discard the outer levels of args, and then substitute in the
17756 template args from the enclosing class. */
17757 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17758 partial_spec_args = tsubst_template_args
17759 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17761 /* PARMS already refers to just the innermost parms, but the
17762 template parms in partial_spec_args had their levels lowered
17763 by tsubst, so we need to do the same for the parm list. We
17764 can't just tsubst the TREE_VEC itself, as tsubst wants to
17765 treat a TREE_VEC as an argument vector. */
17766 parms = copy_node (parms);
17767 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17768 TREE_VEC_ELT (parms, i) =
17769 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17773 partial_spec_args =
17774 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17775 add_to_template_args (outer_args,
17776 partial_spec_args),
17778 /*require_all_args=*/true,
17779 /*use_default_args=*/true);
17781 --processing_template_decl;
17783 if (partial_spec_args == error_mark_node)
17784 return error_mark_node;
17786 spec_args = get_class_bindings (parms,
17792 spec_args = add_to_template_args (outer_args, spec_args);
17793 list = tree_cons (spec_args, TREE_VALUE (t), list);
17794 TREE_TYPE (list) = TREE_TYPE (t);
17801 ambiguous_p = false;
17804 t = TREE_CHAIN (t);
17805 for (; t; t = TREE_CHAIN (t))
17807 fate = more_specialized_class (champ, t);
17814 t = TREE_CHAIN (t);
17817 ambiguous_p = true;
17826 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17828 fate = more_specialized_class (champ, t);
17831 ambiguous_p = true;
17839 char *spaces = NULL;
17840 if (!(complain & tf_error))
17841 return error_mark_node;
17842 error ("ambiguous class template instantiation for %q#T", type);
17843 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17844 for (t = list; t; t = TREE_CHAIN (t))
17846 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17847 spaces = spaces ? spaces : get_spaces (str);
17850 return error_mark_node;
17856 /* Explicitly instantiate DECL. */
17859 do_decl_instantiation (tree decl, tree storage)
17861 tree result = NULL_TREE;
17864 if (!decl || decl == error_mark_node)
17865 /* An error occurred, for which grokdeclarator has already issued
17866 an appropriate message. */
17868 else if (! DECL_LANG_SPECIFIC (decl))
17870 error ("explicit instantiation of non-template %q#D", decl);
17873 else if (TREE_CODE (decl) == VAR_DECL)
17875 /* There is an asymmetry here in the way VAR_DECLs and
17876 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17877 the latter, the DECL we get back will be marked as a
17878 template instantiation, and the appropriate
17879 DECL_TEMPLATE_INFO will be set up. This does not happen for
17880 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17881 should handle VAR_DECLs as it currently handles
17883 if (!DECL_CLASS_SCOPE_P (decl))
17885 error ("%qD is not a static data member of a class template", decl);
17888 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17889 if (!result || TREE_CODE (result) != VAR_DECL)
17891 error ("no matching template for %qD found", decl);
17894 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17896 error ("type %qT for explicit instantiation %qD does not match "
17897 "declared type %qT", TREE_TYPE (result), decl,
17902 else if (TREE_CODE (decl) != FUNCTION_DECL)
17904 error ("explicit instantiation of %q#D", decl);
17910 /* Check for various error cases. Note that if the explicit
17911 instantiation is valid the RESULT will currently be marked as an
17912 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17913 until we get here. */
17915 if (DECL_TEMPLATE_SPECIALIZATION (result))
17917 /* DR 259 [temp.spec].
17919 Both an explicit instantiation and a declaration of an explicit
17920 specialization shall not appear in a program unless the explicit
17921 instantiation follows a declaration of the explicit specialization.
17923 For a given set of template parameters, if an explicit
17924 instantiation of a template appears after a declaration of an
17925 explicit specialization for that template, the explicit
17926 instantiation has no effect. */
17929 else if (DECL_EXPLICIT_INSTANTIATION (result))
17933 No program shall explicitly instantiate any template more
17936 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17937 the first instantiation was `extern' and the second is not,
17938 and EXTERN_P for the opposite case. */
17939 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17940 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17941 /* If an "extern" explicit instantiation follows an ordinary
17942 explicit instantiation, the template is instantiated. */
17946 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17948 error ("no matching template for %qD found", result);
17951 else if (!DECL_TEMPLATE_INFO (result))
17953 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17957 if (storage == NULL_TREE)
17959 else if (storage == ridpointers[(int) RID_EXTERN])
17961 if (!in_system_header && (cxx_dialect == cxx98))
17962 pedwarn (input_location, OPT_pedantic,
17963 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17968 error ("storage class %qD applied to template instantiation", storage);
17970 check_explicit_instantiation_namespace (result);
17971 mark_decl_instantiated (result, extern_p);
17973 instantiate_decl (result, /*defer_ok=*/1,
17974 /*expl_inst_class_mem_p=*/false);
17978 mark_class_instantiated (tree t, int extern_p)
17980 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17981 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17982 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17983 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17986 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17987 rest_of_type_compilation (t, 1);
17991 /* Called from do_type_instantiation through binding_table_foreach to
17992 do recursive instantiation for the type bound in ENTRY. */
17994 bt_instantiate_type_proc (binding_entry entry, void *data)
17996 tree storage = *(tree *) data;
17998 if (MAYBE_CLASS_TYPE_P (entry->type)
17999 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
18000 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
18003 /* Called from do_type_instantiation to instantiate a member
18004 (a member function or a static member variable) of an
18005 explicitly instantiated class template. */
18007 instantiate_class_member (tree decl, int extern_p)
18009 mark_decl_instantiated (decl, extern_p);
18011 instantiate_decl (decl, /*defer_ok=*/1,
18012 /*expl_inst_class_mem_p=*/true);
18015 /* Perform an explicit instantiation of template class T. STORAGE, if
18016 non-null, is the RID for extern, inline or static. COMPLAIN is
18017 nonzero if this is called from the parser, zero if called recursively,
18018 since the standard is unclear (as detailed below). */
18021 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
18026 int previous_instantiation_extern_p = 0;
18028 if (TREE_CODE (t) == TYPE_DECL)
18031 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
18034 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
18036 error ("explicit instantiation of non-class template %qD", tmpl);
18038 error ("explicit instantiation of non-template type %qT", t);
18044 if (!COMPLETE_TYPE_P (t))
18046 if (complain & tf_error)
18047 error ("explicit instantiation of %q#T before definition of template",
18052 if (storage != NULL_TREE)
18054 if (!in_system_header)
18056 if (storage == ridpointers[(int) RID_EXTERN])
18058 if (cxx_dialect == cxx98)
18059 pedwarn (input_location, OPT_pedantic,
18060 "ISO C++ 1998 forbids the use of %<extern%> on "
18061 "explicit instantiations");
18064 pedwarn (input_location, OPT_pedantic,
18065 "ISO C++ forbids the use of %qE"
18066 " on explicit instantiations", storage);
18069 if (storage == ridpointers[(int) RID_INLINE])
18071 else if (storage == ridpointers[(int) RID_EXTERN])
18073 else if (storage == ridpointers[(int) RID_STATIC])
18077 error ("storage class %qD applied to template instantiation",
18083 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18085 /* DR 259 [temp.spec].
18087 Both an explicit instantiation and a declaration of an explicit
18088 specialization shall not appear in a program unless the explicit
18089 instantiation follows a declaration of the explicit specialization.
18091 For a given set of template parameters, if an explicit
18092 instantiation of a template appears after a declaration of an
18093 explicit specialization for that template, the explicit
18094 instantiation has no effect. */
18097 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18101 No program shall explicitly instantiate any template more
18104 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18105 instantiation was `extern'. If EXTERN_P then the second is.
18106 These cases are OK. */
18107 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18109 if (!previous_instantiation_extern_p && !extern_p
18110 && (complain & tf_error))
18111 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18113 /* If we've already instantiated the template, just return now. */
18114 if (!CLASSTYPE_INTERFACE_ONLY (t))
18118 check_explicit_instantiation_namespace (TYPE_NAME (t));
18119 mark_class_instantiated (t, extern_p);
18127 /* In contrast to implicit instantiation, where only the
18128 declarations, and not the definitions, of members are
18129 instantiated, we have here:
18133 The explicit instantiation of a class template specialization
18134 implies the instantiation of all of its members not
18135 previously explicitly specialized in the translation unit
18136 containing the explicit instantiation.
18138 Of course, we can't instantiate member template classes, since
18139 we don't have any arguments for them. Note that the standard
18140 is unclear on whether the instantiation of the members are
18141 *explicit* instantiations or not. However, the most natural
18142 interpretation is that it should be an explicit instantiation. */
18145 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18146 if (TREE_CODE (tmp) == FUNCTION_DECL
18147 && DECL_TEMPLATE_INSTANTIATION (tmp))
18148 instantiate_class_member (tmp, extern_p);
18150 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18151 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18152 instantiate_class_member (tmp, extern_p);
18154 if (CLASSTYPE_NESTED_UTDS (t))
18155 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18156 bt_instantiate_type_proc, &storage);
18160 /* Given a function DECL, which is a specialization of TMPL, modify
18161 DECL to be a re-instantiation of TMPL with the same template
18162 arguments. TMPL should be the template into which tsubst'ing
18163 should occur for DECL, not the most general template.
18165 One reason for doing this is a scenario like this:
18168 void f(const T&, int i);
18170 void g() { f(3, 7); }
18173 void f(const T& t, const int i) { }
18175 Note that when the template is first instantiated, with
18176 instantiate_template, the resulting DECL will have no name for the
18177 first parameter, and the wrong type for the second. So, when we go
18178 to instantiate the DECL, we regenerate it. */
18181 regenerate_decl_from_template (tree decl, tree tmpl)
18183 /* The arguments used to instantiate DECL, from the most general
18188 args = DECL_TI_ARGS (decl);
18189 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18191 /* Make sure that we can see identifiers, and compute access
18193 push_access_scope (decl);
18195 if (TREE_CODE (decl) == FUNCTION_DECL)
18203 args_depth = TMPL_ARGS_DEPTH (args);
18204 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18205 if (args_depth > parms_depth)
18206 args = get_innermost_template_args (args, parms_depth);
18208 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18209 args, tf_error, NULL_TREE,
18210 /*defer_ok*/false);
18211 if (specs && specs != error_mark_node)
18212 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18215 /* Merge parameter declarations. */
18216 decl_parm = skip_artificial_parms_for (decl,
18217 DECL_ARGUMENTS (decl));
18219 = skip_artificial_parms_for (code_pattern,
18220 DECL_ARGUMENTS (code_pattern));
18221 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18226 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18227 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18228 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18230 parm_type = type_decays_to (parm_type);
18231 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18232 TREE_TYPE (decl_parm) = parm_type;
18233 attributes = DECL_ATTRIBUTES (pattern_parm);
18234 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18236 DECL_ATTRIBUTES (decl_parm) = attributes;
18237 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18239 decl_parm = DECL_CHAIN (decl_parm);
18240 pattern_parm = DECL_CHAIN (pattern_parm);
18242 /* Merge any parameters that match with the function parameter
18244 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18247 tree expanded_types;
18248 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18249 the parameters in this function parameter pack. */
18250 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18251 args, tf_error, NULL_TREE);
18252 len = TREE_VEC_LENGTH (expanded_types);
18253 for (i = 0; i < len; i++)
18258 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18259 /* Rename the parameter to include the index. */
18260 DECL_NAME (decl_parm) =
18261 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18262 parm_type = TREE_VEC_ELT (expanded_types, i);
18263 parm_type = type_decays_to (parm_type);
18264 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18265 TREE_TYPE (decl_parm) = parm_type;
18266 attributes = DECL_ATTRIBUTES (pattern_parm);
18267 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18269 DECL_ATTRIBUTES (decl_parm) = attributes;
18270 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18272 decl_parm = DECL_CHAIN (decl_parm);
18275 /* Merge additional specifiers from the CODE_PATTERN. */
18276 if (DECL_DECLARED_INLINE_P (code_pattern)
18277 && !DECL_DECLARED_INLINE_P (decl))
18278 DECL_DECLARED_INLINE_P (decl) = 1;
18280 else if (TREE_CODE (decl) == VAR_DECL)
18282 DECL_INITIAL (decl) =
18283 tsubst_expr (DECL_INITIAL (code_pattern), args,
18284 tf_error, DECL_TI_TEMPLATE (decl),
18285 /*integral_constant_expression_p=*/false);
18286 if (VAR_HAD_UNKNOWN_BOUND (decl))
18287 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18288 tf_error, DECL_TI_TEMPLATE (decl));
18291 gcc_unreachable ();
18293 pop_access_scope (decl);
18296 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18297 substituted to get DECL. */
18300 template_for_substitution (tree decl)
18302 tree tmpl = DECL_TI_TEMPLATE (decl);
18304 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18305 for the instantiation. This is not always the most general
18306 template. Consider, for example:
18309 struct S { template <class U> void f();
18310 template <> void f<int>(); };
18312 and an instantiation of S<double>::f<int>. We want TD to be the
18313 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18314 while (/* An instantiation cannot have a definition, so we need a
18315 more general template. */
18316 DECL_TEMPLATE_INSTANTIATION (tmpl)
18317 /* We must also deal with friend templates. Given:
18319 template <class T> struct S {
18320 template <class U> friend void f() {};
18323 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18324 so far as the language is concerned, but that's still
18325 where we get the pattern for the instantiation from. On
18326 other hand, if the definition comes outside the class, say:
18328 template <class T> struct S {
18329 template <class U> friend void f();
18331 template <class U> friend void f() {}
18333 we don't need to look any further. That's what the check for
18334 DECL_INITIAL is for. */
18335 || (TREE_CODE (decl) == FUNCTION_DECL
18336 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18337 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18339 /* The present template, TD, should not be a definition. If it
18340 were a definition, we should be using it! Note that we
18341 cannot restructure the loop to just keep going until we find
18342 a template with a definition, since that might go too far if
18343 a specialization was declared, but not defined. */
18344 gcc_assert (TREE_CODE (decl) != VAR_DECL
18345 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18347 /* Fetch the more general template. */
18348 tmpl = DECL_TI_TEMPLATE (tmpl);
18354 /* Returns true if we need to instantiate this template instance even if we
18355 know we aren't going to emit it.. */
18358 always_instantiate_p (tree decl)
18360 /* We always instantiate inline functions so that we can inline them. An
18361 explicit instantiation declaration prohibits implicit instantiation of
18362 non-inline functions. With high levels of optimization, we would
18363 normally inline non-inline functions -- but we're not allowed to do
18364 that for "extern template" functions. Therefore, we check
18365 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18366 return ((TREE_CODE (decl) == FUNCTION_DECL
18367 && DECL_DECLARED_INLINE_P (decl))
18368 /* And we need to instantiate static data members so that
18369 their initializers are available in integral constant
18371 || (TREE_CODE (decl) == VAR_DECL
18372 && decl_maybe_constant_var_p (decl)));
18375 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18376 instantiate it now, modifying TREE_TYPE (fn). */
18379 maybe_instantiate_noexcept (tree fn)
18381 tree fntype, spec, noex, clone;
18383 if (DECL_CLONED_FUNCTION_P (fn))
18384 fn = DECL_CLONED_FUNCTION (fn);
18385 fntype = TREE_TYPE (fn);
18386 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18388 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18391 noex = TREE_PURPOSE (spec);
18393 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18395 if (push_tinst_level (fn))
18397 push_access_scope (fn);
18398 input_location = DECL_SOURCE_LOCATION (fn);
18399 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18400 DEFERRED_NOEXCEPT_ARGS (noex),
18401 tf_warning_or_error, fn,
18402 /*function_p=*/false,
18403 /*integral_constant_expression_p=*/true);
18404 pop_access_scope (fn);
18405 pop_tinst_level ();
18406 spec = build_noexcept_spec (noex, tf_warning_or_error);
18407 if (spec == error_mark_node)
18408 spec = noexcept_false_spec;
18411 spec = noexcept_false_spec;
18415 /* This is an implicitly declared function, so NOEX is a list of
18416 other functions to evaluate and merge. */
18418 spec = noexcept_true_spec;
18419 for (elt = noex; elt; elt = OVL_NEXT (elt))
18421 tree fn = OVL_CURRENT (elt);
18423 maybe_instantiate_noexcept (fn);
18424 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18425 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18429 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18431 FOR_EACH_CLONE (clone, fn)
18433 if (TREE_TYPE (clone) == fntype)
18434 TREE_TYPE (clone) = TREE_TYPE (fn);
18436 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18440 /* Produce the definition of D, a _DECL generated from a template. If
18441 DEFER_OK is nonzero, then we don't have to actually do the
18442 instantiation now; we just have to do it sometime. Normally it is
18443 an error if this is an explicit instantiation but D is undefined.
18444 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18445 explicitly instantiated class template. */
18448 instantiate_decl (tree d, int defer_ok,
18449 bool expl_inst_class_mem_p)
18451 tree tmpl = DECL_TI_TEMPLATE (d);
18458 bool pattern_defined;
18460 location_t saved_loc = input_location;
18463 /* This function should only be used to instantiate templates for
18464 functions and static member variables. */
18465 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18466 || TREE_CODE (d) == VAR_DECL);
18468 /* Variables are never deferred; if instantiation is required, they
18469 are instantiated right away. That allows for better code in the
18470 case that an expression refers to the value of the variable --
18471 if the variable has a constant value the referring expression can
18472 take advantage of that fact. */
18473 if (TREE_CODE (d) == VAR_DECL
18474 || DECL_DECLARED_CONSTEXPR_P (d))
18477 /* Don't instantiate cloned functions. Instead, instantiate the
18478 functions they cloned. */
18479 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18480 d = DECL_CLONED_FUNCTION (d);
18482 if (DECL_TEMPLATE_INSTANTIATED (d)
18483 || (TREE_CODE (d) == FUNCTION_DECL
18484 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18485 || DECL_TEMPLATE_SPECIALIZATION (d))
18486 /* D has already been instantiated or explicitly specialized, so
18487 there's nothing for us to do here.
18489 It might seem reasonable to check whether or not D is an explicit
18490 instantiation, and, if so, stop here. But when an explicit
18491 instantiation is deferred until the end of the compilation,
18492 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18493 the instantiation. */
18496 /* Check to see whether we know that this template will be
18497 instantiated in some other file, as with "extern template"
18499 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18501 /* In general, we do not instantiate such templates. */
18502 if (external_p && !always_instantiate_p (d))
18505 gen_tmpl = most_general_template (tmpl);
18506 gen_args = DECL_TI_ARGS (d);
18508 if (tmpl != gen_tmpl)
18509 /* We should already have the extra args. */
18510 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18511 == TMPL_ARGS_DEPTH (gen_args));
18512 /* And what's in the hash table should match D. */
18513 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18514 || spec == NULL_TREE);
18516 /* This needs to happen before any tsubsting. */
18517 if (! push_tinst_level (d))
18520 timevar_push (TV_TEMPLATE_INST);
18522 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18523 for the instantiation. */
18524 td = template_for_substitution (d);
18525 code_pattern = DECL_TEMPLATE_RESULT (td);
18527 /* We should never be trying to instantiate a member of a class
18528 template or partial specialization. */
18529 gcc_assert (d != code_pattern);
18531 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18532 || DECL_TEMPLATE_SPECIALIZATION (td))
18533 /* In the case of a friend template whose definition is provided
18534 outside the class, we may have too many arguments. Drop the
18535 ones we don't need. The same is true for specializations. */
18536 args = get_innermost_template_args
18537 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18541 if (TREE_CODE (d) == FUNCTION_DECL)
18542 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18543 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18545 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18547 /* We may be in the middle of deferred access check. Disable it now. */
18548 push_deferring_access_checks (dk_no_deferred);
18550 /* Unless an explicit instantiation directive has already determined
18551 the linkage of D, remember that a definition is available for
18553 if (pattern_defined
18554 && !DECL_INTERFACE_KNOWN (d)
18555 && !DECL_NOT_REALLY_EXTERN (d))
18556 mark_definable (d);
18558 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18559 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18560 input_location = DECL_SOURCE_LOCATION (d);
18562 /* If D is a member of an explicitly instantiated class template,
18563 and no definition is available, treat it like an implicit
18565 if (!pattern_defined && expl_inst_class_mem_p
18566 && DECL_EXPLICIT_INSTANTIATION (d))
18568 /* Leave linkage flags alone on instantiations with anonymous
18570 if (TREE_PUBLIC (d))
18572 DECL_NOT_REALLY_EXTERN (d) = 0;
18573 DECL_INTERFACE_KNOWN (d) = 0;
18575 SET_DECL_IMPLICIT_INSTANTIATION (d);
18578 if (TREE_CODE (d) == FUNCTION_DECL)
18579 maybe_instantiate_noexcept (d);
18581 /* Recheck the substitutions to obtain any warning messages
18582 about ignoring cv qualifiers. Don't do this for artificial decls,
18583 as it breaks the context-sensitive substitution for lambda op(). */
18584 if (!defer_ok && !DECL_ARTIFICIAL (d))
18586 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18587 tree type = TREE_TYPE (gen);
18589 /* Make sure that we can see identifiers, and compute access
18590 correctly. D is already the target FUNCTION_DECL with the
18592 push_access_scope (d);
18594 if (TREE_CODE (gen) == FUNCTION_DECL)
18596 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18597 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18598 d, /*defer_ok*/true);
18599 /* Don't simply tsubst the function type, as that will give
18600 duplicate warnings about poor parameter qualifications.
18601 The function arguments are the same as the decl_arguments
18602 without the top level cv qualifiers. */
18603 type = TREE_TYPE (type);
18605 tsubst (type, gen_args, tf_warning_or_error, d);
18607 pop_access_scope (d);
18610 /* Defer all other templates, unless we have been explicitly
18611 forbidden from doing so. */
18612 if (/* If there is no definition, we cannot instantiate the
18615 /* If it's OK to postpone instantiation, do so. */
18617 /* If this is a static data member that will be defined
18618 elsewhere, we don't want to instantiate the entire data
18619 member, but we do want to instantiate the initializer so that
18620 we can substitute that elsewhere. */
18621 || (external_p && TREE_CODE (d) == VAR_DECL))
18623 /* The definition of the static data member is now required so
18624 we must substitute the initializer. */
18625 if (TREE_CODE (d) == VAR_DECL
18626 && !DECL_INITIAL (d)
18627 && DECL_INITIAL (code_pattern))
18631 bool const_init = false;
18633 ns = decl_namespace_context (d);
18634 push_nested_namespace (ns);
18635 push_nested_class (DECL_CONTEXT (d));
18636 init = tsubst_expr (DECL_INITIAL (code_pattern),
18638 tf_warning_or_error, NULL_TREE,
18639 /*integral_constant_expression_p=*/false);
18640 /* Make sure the initializer is still constant, in case of
18641 circular dependency (template/instantiate6.C). */
18643 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18644 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18645 /*asmspec_tree=*/NULL_TREE,
18646 LOOKUP_ONLYCONVERTING);
18647 pop_nested_class ();
18648 pop_nested_namespace (ns);
18651 /* We restore the source position here because it's used by
18652 add_pending_template. */
18653 input_location = saved_loc;
18655 if (at_eof && !pattern_defined
18656 && DECL_EXPLICIT_INSTANTIATION (d)
18657 && DECL_NOT_REALLY_EXTERN (d))
18660 The definition of a non-exported function template, a
18661 non-exported member function template, or a non-exported
18662 member function or static data member of a class template
18663 shall be present in every translation unit in which it is
18664 explicitly instantiated. */
18665 permerror (input_location, "explicit instantiation of %qD "
18666 "but no definition available", d);
18668 /* If we're in unevaluated context, we just wanted to get the
18669 constant value; this isn't an odr use, so don't queue
18670 a full instantiation. */
18671 if (cp_unevaluated_operand != 0)
18673 /* ??? Historically, we have instantiated inline functions, even
18674 when marked as "extern template". */
18675 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18676 add_pending_template (d);
18679 /* Tell the repository that D is available in this translation unit
18680 -- and see if it is supposed to be instantiated here. */
18681 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18683 /* In a PCH file, despite the fact that the repository hasn't
18684 requested instantiation in the PCH it is still possible that
18685 an instantiation will be required in a file that includes the
18688 add_pending_template (d);
18689 /* Instantiate inline functions so that the inliner can do its
18690 job, even though we'll not be emitting a copy of this
18692 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18696 need_push = !cfun || !global_bindings_p ();
18698 push_to_top_level ();
18700 /* Mark D as instantiated so that recursive calls to
18701 instantiate_decl do not try to instantiate it again. */
18702 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18704 /* Regenerate the declaration in case the template has been modified
18705 by a subsequent redeclaration. */
18706 regenerate_decl_from_template (d, td);
18708 /* We already set the file and line above. Reset them now in case
18709 they changed as a result of calling regenerate_decl_from_template. */
18710 input_location = DECL_SOURCE_LOCATION (d);
18712 if (TREE_CODE (d) == VAR_DECL)
18715 bool const_init = false;
18717 /* Clear out DECL_RTL; whatever was there before may not be right
18718 since we've reset the type of the declaration. */
18719 SET_DECL_RTL (d, NULL);
18720 DECL_IN_AGGR_P (d) = 0;
18722 /* The initializer is placed in DECL_INITIAL by
18723 regenerate_decl_from_template so we don't need to
18724 push/pop_access_scope again here. Pull it out so that
18725 cp_finish_decl can process it. */
18726 init = DECL_INITIAL (d);
18727 DECL_INITIAL (d) = NULL_TREE;
18728 DECL_INITIALIZED_P (d) = 0;
18730 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18731 initializer. That function will defer actual emission until
18732 we have a chance to determine linkage. */
18733 DECL_EXTERNAL (d) = 0;
18735 /* Enter the scope of D so that access-checking works correctly. */
18736 push_nested_class (DECL_CONTEXT (d));
18737 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18738 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18739 pop_nested_class ();
18741 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18742 synthesize_method (d);
18743 else if (TREE_CODE (d) == FUNCTION_DECL)
18745 htab_t saved_local_specializations;
18750 /* Save away the current list, in case we are instantiating one
18751 template from within the body of another. */
18752 saved_local_specializations = local_specializations;
18754 /* Set up the list of local specializations. */
18755 local_specializations = htab_create (37,
18756 hash_local_specialization,
18757 eq_local_specializations,
18760 /* Set up context. */
18761 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18763 /* Create substitution entries for the parameters. */
18764 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18765 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18766 spec_parm = DECL_ARGUMENTS (d);
18767 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18769 register_local_specialization (spec_parm, tmpl_parm);
18770 spec_parm = skip_artificial_parms_for (d, spec_parm);
18771 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18773 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18775 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18777 register_local_specialization (spec_parm, tmpl_parm);
18778 spec_parm = DECL_CHAIN (spec_parm);
18782 /* Register the (value) argument pack as a specialization of
18783 TMPL_PARM, then move on. */
18784 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18785 register_local_specialization (argpack, tmpl_parm);
18788 gcc_assert (!spec_parm);
18790 /* Substitute into the body of the function. */
18791 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18792 tf_warning_or_error, tmpl,
18793 /*integral_constant_expression_p=*/false);
18795 /* Set the current input_location to the end of the function
18796 so that finish_function knows where we are. */
18797 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18799 /* We don't need the local specializations any more. */
18800 htab_delete (local_specializations);
18801 local_specializations = saved_local_specializations;
18803 /* Finish the function. */
18804 d = finish_function (0);
18805 expand_or_defer_fn (d);
18808 /* We're not deferring instantiation any more. */
18809 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18812 pop_from_top_level ();
18815 input_location = saved_loc;
18816 pop_deferring_access_checks ();
18817 pop_tinst_level ();
18819 timevar_pop (TV_TEMPLATE_INST);
18824 /* Run through the list of templates that we wish we could
18825 instantiate, and instantiate any we can. RETRIES is the
18826 number of times we retry pending template instantiation. */
18829 instantiate_pending_templates (int retries)
18832 location_t saved_loc = input_location;
18834 /* Instantiating templates may trigger vtable generation. This in turn
18835 may require further template instantiations. We place a limit here
18836 to avoid infinite loop. */
18837 if (pending_templates && retries >= max_tinst_depth)
18839 tree decl = pending_templates->tinst->decl;
18841 error ("template instantiation depth exceeds maximum of %d"
18842 " instantiating %q+D, possibly from virtual table generation"
18843 " (use -ftemplate-depth= to increase the maximum)",
18844 max_tinst_depth, decl);
18845 if (TREE_CODE (decl) == FUNCTION_DECL)
18846 /* Pretend that we defined it. */
18847 DECL_INITIAL (decl) = error_mark_node;
18853 struct pending_template **t = &pending_templates;
18854 struct pending_template *last = NULL;
18858 tree instantiation = reopen_tinst_level ((*t)->tinst);
18859 bool complete = false;
18861 if (TYPE_P (instantiation))
18865 if (!COMPLETE_TYPE_P (instantiation))
18867 instantiate_class_template (instantiation);
18868 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18869 for (fn = TYPE_METHODS (instantiation);
18871 fn = TREE_CHAIN (fn))
18872 if (! DECL_ARTIFICIAL (fn))
18873 instantiate_decl (fn,
18875 /*expl_inst_class_mem_p=*/false);
18876 if (COMPLETE_TYPE_P (instantiation))
18880 complete = COMPLETE_TYPE_P (instantiation);
18884 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18885 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18888 = instantiate_decl (instantiation,
18890 /*expl_inst_class_mem_p=*/false);
18891 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18895 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18896 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18900 /* If INSTANTIATION has been instantiated, then we don't
18901 need to consider it again in the future. */
18909 current_tinst_level = NULL;
18911 last_pending_template = last;
18913 while (reconsider);
18915 input_location = saved_loc;
18918 /* Substitute ARGVEC into T, which is a list of initializers for
18919 either base class or a non-static data member. The TREE_PURPOSEs
18920 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18921 instantiate_decl. */
18924 tsubst_initializer_list (tree t, tree argvec)
18926 tree inits = NULL_TREE;
18928 for (; t; t = TREE_CHAIN (t))
18932 tree expanded_bases = NULL_TREE;
18933 tree expanded_arguments = NULL_TREE;
18936 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18941 /* Expand the base class expansion type into separate base
18943 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18944 tf_warning_or_error,
18946 if (expanded_bases == error_mark_node)
18949 /* We'll be building separate TREE_LISTs of arguments for
18951 len = TREE_VEC_LENGTH (expanded_bases);
18952 expanded_arguments = make_tree_vec (len);
18953 for (i = 0; i < len; i++)
18954 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18956 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18957 expand each argument in the TREE_VALUE of t. */
18958 expr = make_node (EXPR_PACK_EXPANSION);
18959 PACK_EXPANSION_LOCAL_P (expr) = true;
18960 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18961 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18963 if (TREE_VALUE (t) == void_type_node)
18964 /* VOID_TYPE_NODE is used to indicate
18965 value-initialization. */
18967 for (i = 0; i < len; i++)
18968 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18972 /* Substitute parameter packs into each argument in the
18974 in_base_initializer = 1;
18975 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18977 tree expanded_exprs;
18979 /* Expand the argument. */
18980 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18982 = tsubst_pack_expansion (expr, argvec,
18983 tf_warning_or_error,
18985 if (expanded_exprs == error_mark_node)
18988 /* Prepend each of the expanded expressions to the
18989 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18990 for (i = 0; i < len; i++)
18992 TREE_VEC_ELT (expanded_arguments, i) =
18993 tree_cons (NULL_TREE,
18994 TREE_VEC_ELT (expanded_exprs, i),
18995 TREE_VEC_ELT (expanded_arguments, i));
18998 in_base_initializer = 0;
19000 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
19001 since we built them backwards. */
19002 for (i = 0; i < len; i++)
19004 TREE_VEC_ELT (expanded_arguments, i) =
19005 nreverse (TREE_VEC_ELT (expanded_arguments, i));
19010 for (i = 0; i < len; ++i)
19012 if (expanded_bases)
19014 decl = TREE_VEC_ELT (expanded_bases, i);
19015 decl = expand_member_init (decl);
19016 init = TREE_VEC_ELT (expanded_arguments, i);
19021 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
19022 tf_warning_or_error, NULL_TREE);
19024 decl = expand_member_init (decl);
19025 if (decl && !DECL_P (decl))
19026 in_base_initializer = 1;
19028 init = TREE_VALUE (t);
19030 if (init != void_type_node)
19031 init = tsubst_expr (init, argvec,
19032 tf_warning_or_error, NULL_TREE,
19033 /*integral_constant_expression_p=*/false);
19034 if (init == NULL_TREE && tmp != NULL_TREE)
19035 /* If we had an initializer but it instantiated to nothing,
19036 value-initialize the object. This will only occur when
19037 the initializer was a pack expansion where the parameter
19038 packs used in that expansion were of length zero. */
19039 init = void_type_node;
19040 in_base_initializer = 0;
19045 init = build_tree_list (decl, init);
19046 TREE_CHAIN (init) = inits;
19054 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
19057 set_current_access_from_decl (tree decl)
19059 if (TREE_PRIVATE (decl))
19060 current_access_specifier = access_private_node;
19061 else if (TREE_PROTECTED (decl))
19062 current_access_specifier = access_protected_node;
19064 current_access_specifier = access_public_node;
19067 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
19068 is the instantiation (which should have been created with
19069 start_enum) and ARGS are the template arguments to use. */
19072 tsubst_enum (tree tag, tree newtag, tree args)
19076 if (SCOPED_ENUM_P (newtag))
19077 begin_scope (sk_scoped_enum, newtag);
19079 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
19084 decl = TREE_VALUE (e);
19085 /* Note that in a template enum, the TREE_VALUE is the
19086 CONST_DECL, not the corresponding INTEGER_CST. */
19087 value = tsubst_expr (DECL_INITIAL (decl),
19088 args, tf_warning_or_error, NULL_TREE,
19089 /*integral_constant_expression_p=*/true);
19091 /* Give this enumeration constant the correct access. */
19092 set_current_access_from_decl (decl);
19094 /* Actually build the enumerator itself. */
19096 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19099 if (SCOPED_ENUM_P (newtag))
19102 finish_enum_value_list (newtag);
19103 finish_enum (newtag);
19105 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19106 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19109 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19110 its type -- but without substituting the innermost set of template
19111 arguments. So, innermost set of template parameters will appear in
19115 get_mostly_instantiated_function_type (tree decl)
19123 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19124 targs = DECL_TI_ARGS (decl);
19125 tparms = DECL_TEMPLATE_PARMS (tmpl);
19126 parm_depth = TMPL_PARMS_DEPTH (tparms);
19128 /* There should be as many levels of arguments as there are levels
19130 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19132 fn_type = TREE_TYPE (tmpl);
19134 if (parm_depth == 1)
19135 /* No substitution is necessary. */
19142 /* Replace the innermost level of the TARGS with NULL_TREEs to
19143 let tsubst know not to substitute for those parameters. */
19144 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19145 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19146 SET_TMPL_ARGS_LEVEL (partial_args, i,
19147 TMPL_ARGS_LEVEL (targs, i));
19148 SET_TMPL_ARGS_LEVEL (partial_args,
19149 TMPL_ARGS_DEPTH (targs),
19150 make_tree_vec (DECL_NTPARMS (tmpl)));
19152 /* Make sure that we can see identifiers, and compute access
19154 push_access_scope (decl);
19156 ++processing_template_decl;
19157 /* Now, do the (partial) substitution to figure out the
19158 appropriate function type. */
19159 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19160 --processing_template_decl;
19162 /* Substitute into the template parameters to obtain the real
19163 innermost set of parameters. This step is important if the
19164 innermost set of template parameters contains value
19165 parameters whose types depend on outer template parameters. */
19166 TREE_VEC_LENGTH (partial_args)--;
19167 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19169 pop_access_scope (decl);
19175 /* Return truthvalue if we're processing a template different from
19176 the last one involved in diagnostics. */
19178 problematic_instantiation_changed (void)
19180 return current_tinst_level != last_error_tinst_level;
19183 /* Remember current template involved in diagnostics. */
19185 record_last_problematic_instantiation (void)
19187 last_error_tinst_level = current_tinst_level;
19190 struct tinst_level *
19191 current_instantiation (void)
19193 return current_tinst_level;
19196 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19197 type. Return zero for ok, nonzero for disallowed. Issue error and
19198 warning messages under control of COMPLAIN. */
19201 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19203 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19205 else if (POINTER_TYPE_P (type))
19207 else if (TYPE_PTR_TO_MEMBER_P (type))
19209 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19211 else if (TREE_CODE (type) == TYPENAME_TYPE)
19213 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19215 else if (TREE_CODE (type) == NULLPTR_TYPE)
19218 if (complain & tf_error)
19220 if (type == error_mark_node)
19221 inform (input_location, "invalid template non-type parameter");
19223 error ("%q#T is not a valid type for a template non-type parameter",
19229 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19230 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19233 dependent_type_p_r (tree type)
19239 A type is dependent if it is:
19241 -- a template parameter. Template template parameters are types
19242 for us (since TYPE_P holds true for them) so we handle
19244 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19245 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19247 /* -- a qualified-id with a nested-name-specifier which contains a
19248 class-name that names a dependent type or whose unqualified-id
19249 names a dependent type. */
19250 if (TREE_CODE (type) == TYPENAME_TYPE)
19252 /* -- a cv-qualified type where the cv-unqualified type is
19254 type = TYPE_MAIN_VARIANT (type);
19255 /* -- a compound type constructed from any dependent type. */
19256 if (TYPE_PTR_TO_MEMBER_P (type))
19257 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19258 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19260 else if (TREE_CODE (type) == POINTER_TYPE
19261 || TREE_CODE (type) == REFERENCE_TYPE)
19262 return dependent_type_p (TREE_TYPE (type));
19263 else if (TREE_CODE (type) == FUNCTION_TYPE
19264 || TREE_CODE (type) == METHOD_TYPE)
19268 if (dependent_type_p (TREE_TYPE (type)))
19270 for (arg_type = TYPE_ARG_TYPES (type);
19272 arg_type = TREE_CHAIN (arg_type))
19273 if (dependent_type_p (TREE_VALUE (arg_type)))
19277 /* -- an array type constructed from any dependent type or whose
19278 size is specified by a constant expression that is
19281 We checked for type- and value-dependence of the bounds in
19282 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19283 if (TREE_CODE (type) == ARRAY_TYPE)
19285 if (TYPE_DOMAIN (type)
19286 && dependent_type_p (TYPE_DOMAIN (type)))
19288 return dependent_type_p (TREE_TYPE (type));
19291 /* -- a template-id in which either the template name is a template
19293 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19295 /* ... or any of the template arguments is a dependent type or
19296 an expression that is type-dependent or value-dependent. */
19297 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19298 && (any_dependent_template_arguments_p
19299 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19302 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19303 dependent; if the argument of the `typeof' expression is not
19304 type-dependent, then it should already been have resolved. */
19305 if (TREE_CODE (type) == TYPEOF_TYPE
19306 || TREE_CODE (type) == DECLTYPE_TYPE
19307 || TREE_CODE (type) == UNDERLYING_TYPE)
19310 /* A template argument pack is dependent if any of its packed
19312 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19314 tree args = ARGUMENT_PACK_ARGS (type);
19315 int i, len = TREE_VEC_LENGTH (args);
19316 for (i = 0; i < len; ++i)
19317 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19321 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19322 be template parameters. */
19323 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19326 /* The standard does not specifically mention types that are local
19327 to template functions or local classes, but they should be
19328 considered dependent too. For example:
19330 template <int I> void f() {
19335 The size of `E' cannot be known until the value of `I' has been
19336 determined. Therefore, `E' must be considered dependent. */
19337 scope = TYPE_CONTEXT (type);
19338 if (scope && TYPE_P (scope))
19339 return dependent_type_p (scope);
19340 /* Don't use type_dependent_expression_p here, as it can lead
19341 to infinite recursion trying to determine whether a lambda
19342 nested in a lambda is dependent (c++/47687). */
19343 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19344 && DECL_LANG_SPECIFIC (scope)
19345 && DECL_TEMPLATE_INFO (scope)
19346 && (any_dependent_template_arguments_p
19347 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19350 /* Other types are non-dependent. */
19354 /* Returns TRUE if TYPE is dependent, in the sense of
19355 [temp.dep.type]. Note that a NULL type is considered dependent. */
19358 dependent_type_p (tree type)
19360 /* If there are no template parameters in scope, then there can't be
19361 any dependent types. */
19362 if (!processing_template_decl)
19364 /* If we are not processing a template, then nobody should be
19365 providing us with a dependent type. */
19367 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19371 /* If the type is NULL, we have not computed a type for the entity
19372 in question; in that case, the type is dependent. */
19376 /* Erroneous types can be considered non-dependent. */
19377 if (type == error_mark_node)
19380 /* If we have not already computed the appropriate value for TYPE,
19382 if (!TYPE_DEPENDENT_P_VALID (type))
19384 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19385 TYPE_DEPENDENT_P_VALID (type) = 1;
19388 return TYPE_DEPENDENT_P (type);
19391 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19392 lookup. In other words, a dependent type that is not the current
19396 dependent_scope_p (tree scope)
19398 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19399 && !currently_open_class (scope));
19402 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19403 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19406 /* Note that this predicate is not appropriate for general expressions;
19407 only constant expressions (that satisfy potential_constant_expression)
19408 can be tested for value dependence.
19410 We should really also have a predicate for "instantiation-dependent".
19412 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19413 (what about instantiation-dependent constant-expressions?)
19414 is_late_template_attribute: defer if instantiation-dependent.
19415 compute_array_index_type: proceed if constant and not t- or v-dependent
19416 if instantiation-dependent, need to remember full expression
19417 uses_template_parms: FIXME - need to audit callers
19418 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19419 dependent_type_p [array_type]: dependent if index type is dependent
19421 static_assert - instantiation-dependent */
19424 value_dependent_expression_p (tree expression)
19426 if (!processing_template_decl)
19429 /* A name declared with a dependent type. */
19430 if (DECL_P (expression) && type_dependent_expression_p (expression))
19433 switch (TREE_CODE (expression))
19435 case IDENTIFIER_NODE:
19436 /* A name that has not been looked up -- must be dependent. */
19439 case TEMPLATE_PARM_INDEX:
19440 /* A non-type template parm. */
19444 /* A non-type template parm. */
19445 if (DECL_TEMPLATE_PARM_P (expression))
19447 return value_dependent_expression_p (DECL_INITIAL (expression));
19450 /* A constant with literal type and is initialized
19451 with an expression that is value-dependent. */
19452 if (DECL_INITIAL (expression)
19453 && decl_constant_var_p (expression)
19454 && value_dependent_expression_p (DECL_INITIAL (expression)))
19458 case DYNAMIC_CAST_EXPR:
19459 case STATIC_CAST_EXPR:
19460 case CONST_CAST_EXPR:
19461 case REINTERPRET_CAST_EXPR:
19463 /* These expressions are value-dependent if the type to which
19464 the cast occurs is dependent or the expression being casted
19465 is value-dependent. */
19467 tree type = TREE_TYPE (expression);
19469 if (dependent_type_p (type))
19472 /* A functional cast has a list of operands. */
19473 expression = TREE_OPERAND (expression, 0);
19476 /* If there are no operands, it must be an expression such
19477 as "int()". This should not happen for aggregate types
19478 because it would form non-constant expressions. */
19479 gcc_assert (cxx_dialect >= cxx0x
19480 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19485 if (TREE_CODE (expression) == TREE_LIST)
19486 return any_value_dependent_elements_p (expression);
19488 return value_dependent_expression_p (expression);
19494 /* A `sizeof' expression is value-dependent if the operand is
19495 type-dependent or is a pack expansion. */
19496 expression = TREE_OPERAND (expression, 0);
19497 if (PACK_EXPANSION_P (expression))
19499 else if (TYPE_P (expression))
19500 return dependent_type_p (expression);
19501 return type_dependent_expression_p (expression);
19503 case AT_ENCODE_EXPR:
19504 /* An 'encode' expression is value-dependent if the operand is
19506 expression = TREE_OPERAND (expression, 0);
19507 return dependent_type_p (expression);
19509 case NOEXCEPT_EXPR:
19510 expression = TREE_OPERAND (expression, 0);
19511 return type_dependent_expression_p (expression);
19515 tree name = TREE_OPERAND (expression, 1);
19516 return value_dependent_expression_p (name);
19519 case COMPONENT_REF:
19520 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19521 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19523 case NONTYPE_ARGUMENT_PACK:
19524 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19525 is value-dependent. */
19527 tree values = ARGUMENT_PACK_ARGS (expression);
19528 int i, len = TREE_VEC_LENGTH (values);
19530 for (i = 0; i < len; ++i)
19531 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19539 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19540 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19541 || (type2 ? dependent_type_p (type2) : false));
19545 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19546 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19549 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19550 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19554 tree op = TREE_OPERAND (expression, 0);
19555 return (value_dependent_expression_p (op)
19556 || has_value_dependent_address (op));
19561 tree fn = get_callee_fndecl (expression);
19563 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19565 nargs = call_expr_nargs (expression);
19566 for (i = 0; i < nargs; ++i)
19568 tree op = CALL_EXPR_ARG (expression, i);
19569 /* In a call to a constexpr member function, look through the
19570 implicit ADDR_EXPR on the object argument so that it doesn't
19571 cause the call to be considered value-dependent. We also
19572 look through it in potential_constant_expression. */
19573 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19574 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19575 && TREE_CODE (op) == ADDR_EXPR)
19576 op = TREE_OPERAND (op, 0);
19577 if (value_dependent_expression_p (op))
19583 case TEMPLATE_ID_EXPR:
19584 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19586 return type_dependent_expression_p (expression);
19592 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19593 if (value_dependent_expression_p (val))
19599 /* Treat a GNU statement expression as dependent to avoid crashing
19600 under fold_non_dependent_expr; it can't be constant. */
19604 /* A constant expression is value-dependent if any subexpression is
19605 value-dependent. */
19606 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19608 case tcc_reference:
19610 case tcc_comparison:
19612 case tcc_expression:
19615 int i, len = cp_tree_operand_length (expression);
19617 for (i = 0; i < len; i++)
19619 tree t = TREE_OPERAND (expression, i);
19621 /* In some cases, some of the operands may be missing.l
19622 (For example, in the case of PREDECREMENT_EXPR, the
19623 amount to increment by may be missing.) That doesn't
19624 make the expression dependent. */
19625 if (t && value_dependent_expression_p (t))
19636 /* The expression is not value-dependent. */
19640 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19641 [temp.dep.expr]. Note that an expression with no type is
19642 considered dependent. Other parts of the compiler arrange for an
19643 expression with type-dependent subexpressions to have no type, so
19644 this function doesn't have to be fully recursive. */
19647 type_dependent_expression_p (tree expression)
19649 if (!processing_template_decl)
19652 if (expression == error_mark_node)
19655 /* An unresolved name is always dependent. */
19656 if (TREE_CODE (expression) == IDENTIFIER_NODE
19657 || TREE_CODE (expression) == USING_DECL)
19660 /* Some expression forms are never type-dependent. */
19661 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19662 || TREE_CODE (expression) == SIZEOF_EXPR
19663 || TREE_CODE (expression) == ALIGNOF_EXPR
19664 || TREE_CODE (expression) == AT_ENCODE_EXPR
19665 || TREE_CODE (expression) == NOEXCEPT_EXPR
19666 || TREE_CODE (expression) == TRAIT_EXPR
19667 || TREE_CODE (expression) == TYPEID_EXPR
19668 || TREE_CODE (expression) == DELETE_EXPR
19669 || TREE_CODE (expression) == VEC_DELETE_EXPR
19670 || TREE_CODE (expression) == THROW_EXPR)
19673 /* The types of these expressions depends only on the type to which
19674 the cast occurs. */
19675 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19676 || TREE_CODE (expression) == STATIC_CAST_EXPR
19677 || TREE_CODE (expression) == CONST_CAST_EXPR
19678 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19679 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19680 || TREE_CODE (expression) == CAST_EXPR)
19681 return dependent_type_p (TREE_TYPE (expression));
19683 /* The types of these expressions depends only on the type created
19684 by the expression. */
19685 if (TREE_CODE (expression) == NEW_EXPR
19686 || TREE_CODE (expression) == VEC_NEW_EXPR)
19688 /* For NEW_EXPR tree nodes created inside a template, either
19689 the object type itself or a TREE_LIST may appear as the
19691 tree type = TREE_OPERAND (expression, 1);
19692 if (TREE_CODE (type) == TREE_LIST)
19693 /* This is an array type. We need to check array dimensions
19695 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19696 || value_dependent_expression_p
19697 (TREE_OPERAND (TREE_VALUE (type), 1));
19699 return dependent_type_p (type);
19702 if (TREE_CODE (expression) == SCOPE_REF)
19704 tree scope = TREE_OPERAND (expression, 0);
19705 tree name = TREE_OPERAND (expression, 1);
19707 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19708 contains an identifier associated by name lookup with one or more
19709 declarations declared with a dependent type, or...a
19710 nested-name-specifier or qualified-id that names a member of an
19711 unknown specialization. */
19712 return (type_dependent_expression_p (name)
19713 || dependent_scope_p (scope));
19716 if (TREE_CODE (expression) == FUNCTION_DECL
19717 && DECL_LANG_SPECIFIC (expression)
19718 && DECL_TEMPLATE_INFO (expression)
19719 && (any_dependent_template_arguments_p
19720 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19723 if (TREE_CODE (expression) == TEMPLATE_DECL
19724 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19727 if (TREE_CODE (expression) == STMT_EXPR)
19728 expression = stmt_expr_value_expr (expression);
19730 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19735 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19737 if (type_dependent_expression_p (elt))
19743 /* A static data member of the current instantiation with incomplete
19744 array type is type-dependent, as the definition and specializations
19745 can have different bounds. */
19746 if (TREE_CODE (expression) == VAR_DECL
19747 && DECL_CLASS_SCOPE_P (expression)
19748 && dependent_type_p (DECL_CONTEXT (expression))
19749 && VAR_HAD_UNKNOWN_BOUND (expression))
19752 if (TREE_TYPE (expression) == unknown_type_node)
19754 if (TREE_CODE (expression) == ADDR_EXPR)
19755 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19756 if (TREE_CODE (expression) == COMPONENT_REF
19757 || TREE_CODE (expression) == OFFSET_REF)
19759 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19761 expression = TREE_OPERAND (expression, 1);
19762 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19765 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19766 if (TREE_CODE (expression) == SCOPE_REF)
19769 if (BASELINK_P (expression))
19770 expression = BASELINK_FUNCTIONS (expression);
19772 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19774 if (any_dependent_template_arguments_p
19775 (TREE_OPERAND (expression, 1)))
19777 expression = TREE_OPERAND (expression, 0);
19779 gcc_assert (TREE_CODE (expression) == OVERLOAD
19780 || TREE_CODE (expression) == FUNCTION_DECL);
19784 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19786 expression = OVL_NEXT (expression);
19791 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19793 return (dependent_type_p (TREE_TYPE (expression)));
19796 /* Like type_dependent_expression_p, but it also works while not processing
19797 a template definition, i.e. during substitution or mangling. */
19800 type_dependent_expression_p_push (tree expr)
19803 ++processing_template_decl;
19804 b = type_dependent_expression_p (expr);
19805 --processing_template_decl;
19809 /* Returns TRUE if ARGS contains a type-dependent expression. */
19812 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19817 FOR_EACH_VEC_ELT (tree, args, i, arg)
19819 if (type_dependent_expression_p (arg))
19825 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19826 expressions) contains any type-dependent expressions. */
19829 any_type_dependent_elements_p (const_tree list)
19831 for (; list; list = TREE_CHAIN (list))
19832 if (value_dependent_expression_p (TREE_VALUE (list)))
19838 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19839 expressions) contains any value-dependent expressions. */
19842 any_value_dependent_elements_p (const_tree list)
19844 for (; list; list = TREE_CHAIN (list))
19845 if (value_dependent_expression_p (TREE_VALUE (list)))
19851 /* Returns TRUE if the ARG (a template argument) is dependent. */
19854 dependent_template_arg_p (tree arg)
19856 if (!processing_template_decl)
19859 /* Assume a template argument that was wrongly written by the user
19860 is dependent. This is consistent with what
19861 any_dependent_template_arguments_p [that calls this function]
19863 if (!arg || arg == error_mark_node)
19866 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19867 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19869 if (TREE_CODE (arg) == TEMPLATE_DECL
19870 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19871 return dependent_template_p (arg);
19872 else if (ARGUMENT_PACK_P (arg))
19874 tree args = ARGUMENT_PACK_ARGS (arg);
19875 int i, len = TREE_VEC_LENGTH (args);
19876 for (i = 0; i < len; ++i)
19878 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19884 else if (TYPE_P (arg))
19885 return dependent_type_p (arg);
19887 return (type_dependent_expression_p (arg)
19888 || value_dependent_expression_p (arg));
19891 /* Returns true if ARGS (a collection of template arguments) contains
19892 any types that require structural equality testing. */
19895 any_template_arguments_need_structural_equality_p (tree args)
19902 if (args == error_mark_node)
19905 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19907 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19908 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19910 tree arg = TREE_VEC_ELT (level, j);
19911 tree packed_args = NULL_TREE;
19914 if (ARGUMENT_PACK_P (arg))
19916 /* Look inside the argument pack. */
19917 packed_args = ARGUMENT_PACK_ARGS (arg);
19918 len = TREE_VEC_LENGTH (packed_args);
19921 for (k = 0; k < len; ++k)
19924 arg = TREE_VEC_ELT (packed_args, k);
19926 if (error_operand_p (arg))
19928 else if (TREE_CODE (arg) == TEMPLATE_DECL
19929 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19931 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19933 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19934 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19943 /* Returns true if ARGS (a collection of template arguments) contains
19944 any dependent arguments. */
19947 any_dependent_template_arguments_p (const_tree args)
19954 if (args == error_mark_node)
19957 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19959 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19960 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19961 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19968 /* Returns TRUE if the template TMPL is dependent. */
19971 dependent_template_p (tree tmpl)
19973 if (TREE_CODE (tmpl) == OVERLOAD)
19977 if (dependent_template_p (OVL_CURRENT (tmpl)))
19979 tmpl = OVL_NEXT (tmpl);
19984 /* Template template parameters are dependent. */
19985 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19986 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19988 /* So are names that have not been looked up. */
19989 if (TREE_CODE (tmpl) == SCOPE_REF
19990 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19992 /* So are member templates of dependent classes. */
19993 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19994 return dependent_type_p (DECL_CONTEXT (tmpl));
19998 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
20001 dependent_template_id_p (tree tmpl, tree args)
20003 return (dependent_template_p (tmpl)
20004 || any_dependent_template_arguments_p (args));
20007 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
20011 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
20015 if (!processing_template_decl)
20018 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
20020 tree decl = TREE_VEC_ELT (declv, i);
20021 tree init = TREE_VEC_ELT (initv, i);
20022 tree cond = TREE_VEC_ELT (condv, i);
20023 tree incr = TREE_VEC_ELT (incrv, i);
20025 if (type_dependent_expression_p (decl))
20028 if (init && type_dependent_expression_p (init))
20031 if (type_dependent_expression_p (cond))
20034 if (COMPARISON_CLASS_P (cond)
20035 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
20036 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
20039 if (TREE_CODE (incr) == MODOP_EXPR)
20041 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
20042 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
20045 else if (type_dependent_expression_p (incr))
20047 else if (TREE_CODE (incr) == MODIFY_EXPR)
20049 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
20051 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
20053 tree t = TREE_OPERAND (incr, 1);
20054 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
20055 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
20064 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
20065 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
20066 no such TYPE can be found. Note that this function peers inside
20067 uninstantiated templates and therefore should be used only in
20068 extremely limited situations. ONLY_CURRENT_P restricts this
20069 peering to the currently open classes hierarchy (which is required
20070 when comparing types). */
20073 resolve_typename_type (tree type, bool only_current_p)
20082 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
20084 scope = TYPE_CONTEXT (type);
20085 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
20086 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
20087 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
20088 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
20089 identifier of the TYPENAME_TYPE anymore.
20090 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
20091 TYPENAME_TYPE instead, we avoid messing up with a possible
20092 typedef variant case. */
20093 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20095 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20096 it first before we can figure out what NAME refers to. */
20097 if (TREE_CODE (scope) == TYPENAME_TYPE)
20098 scope = resolve_typename_type (scope, only_current_p);
20099 /* If we don't know what SCOPE refers to, then we cannot resolve the
20101 if (TREE_CODE (scope) == TYPENAME_TYPE)
20103 /* If the SCOPE is a template type parameter, we have no way of
20104 resolving the name. */
20105 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20107 /* If the SCOPE is not the current instantiation, there's no reason
20108 to look inside it. */
20109 if (only_current_p && !currently_open_class (scope))
20111 /* If this is a typedef, we don't want to look inside (c++/11987). */
20112 if (typedef_variant_p (type))
20114 /* If SCOPE isn't the template itself, it will not have a valid
20115 TYPE_FIELDS list. */
20116 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20117 /* scope is either the template itself or a compatible instantiation
20118 like X<T>, so look up the name in the original template. */
20119 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20121 /* scope is a partial instantiation, so we can't do the lookup or we
20122 will lose the template arguments. */
20124 /* Enter the SCOPE so that name lookup will be resolved as if we
20125 were in the class definition. In particular, SCOPE will no
20126 longer be considered a dependent type. */
20127 pushed_scope = push_scope (scope);
20128 /* Look up the declaration. */
20129 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20130 tf_warning_or_error);
20132 result = NULL_TREE;
20134 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20135 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20138 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20139 && TREE_CODE (decl) == TYPE_DECL)
20141 result = TREE_TYPE (decl);
20142 if (result == error_mark_node)
20143 result = NULL_TREE;
20145 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20146 && DECL_CLASS_TEMPLATE_P (decl))
20150 /* Obtain the template and the arguments. */
20151 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20152 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20153 /* Instantiate the template. */
20154 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20155 /*entering_scope=*/0,
20156 tf_error | tf_user);
20157 if (result == error_mark_node)
20158 result = NULL_TREE;
20161 /* Leave the SCOPE. */
20163 pop_scope (pushed_scope);
20165 /* If we failed to resolve it, return the original typename. */
20169 /* If lookup found a typename type, resolve that too. */
20170 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20172 /* Ill-formed programs can cause infinite recursion here, so we
20173 must catch that. */
20174 TYPENAME_IS_RESOLVING_P (type) = 1;
20175 result = resolve_typename_type (result, only_current_p);
20176 TYPENAME_IS_RESOLVING_P (type) = 0;
20179 /* Qualify the resulting type. */
20180 quals = cp_type_quals (type);
20182 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20187 /* EXPR is an expression which is not type-dependent. Return a proxy
20188 for EXPR that can be used to compute the types of larger
20189 expressions containing EXPR. */
20192 build_non_dependent_expr (tree expr)
20196 #ifdef ENABLE_CHECKING
20197 /* Try to get a constant value for all non-type-dependent expressions in
20198 order to expose bugs in *_dependent_expression_p and constexpr. */
20199 if (cxx_dialect >= cxx0x)
20200 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20203 /* Preserve OVERLOADs; the functions must be available to resolve
20206 if (TREE_CODE (inner_expr) == STMT_EXPR)
20207 inner_expr = stmt_expr_value_expr (inner_expr);
20208 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20209 inner_expr = TREE_OPERAND (inner_expr, 0);
20210 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20211 inner_expr = TREE_OPERAND (inner_expr, 1);
20212 if (is_overloaded_fn (inner_expr)
20213 || TREE_CODE (inner_expr) == OFFSET_REF)
20215 /* There is no need to return a proxy for a variable. */
20216 if (TREE_CODE (expr) == VAR_DECL)
20218 /* Preserve string constants; conversions from string constants to
20219 "char *" are allowed, even though normally a "const char *"
20220 cannot be used to initialize a "char *". */
20221 if (TREE_CODE (expr) == STRING_CST)
20223 /* Preserve arithmetic constants, as an optimization -- there is no
20224 reason to create a new node. */
20225 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20227 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20228 There is at least one place where we want to know that a
20229 particular expression is a throw-expression: when checking a ?:
20230 expression, there are special rules if the second or third
20231 argument is a throw-expression. */
20232 if (TREE_CODE (expr) == THROW_EXPR)
20235 /* Don't wrap an initializer list, we need to be able to look inside. */
20236 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20239 if (TREE_CODE (expr) == COND_EXPR)
20240 return build3 (COND_EXPR,
20242 TREE_OPERAND (expr, 0),
20243 (TREE_OPERAND (expr, 1)
20244 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20245 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20246 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20247 if (TREE_CODE (expr) == COMPOUND_EXPR
20248 && !COMPOUND_EXPR_OVERLOADED (expr))
20249 return build2 (COMPOUND_EXPR,
20251 TREE_OPERAND (expr, 0),
20252 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20254 /* If the type is unknown, it can't really be non-dependent */
20255 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20257 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20258 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20261 /* ARGS is a vector of expressions as arguments to a function call.
20262 Replace the arguments with equivalent non-dependent expressions.
20263 This modifies ARGS in place. */
20266 make_args_non_dependent (VEC(tree,gc) *args)
20271 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20273 tree newarg = build_non_dependent_expr (arg);
20275 VEC_replace (tree, args, ix, newarg);
20279 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20280 with a level one deeper than the actual template parms. */
20285 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20286 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20287 TYPE_DECL, get_identifier ("auto"), au);
20288 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20289 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20290 (0, processing_template_decl + 1, processing_template_decl + 1,
20291 0, TYPE_NAME (au), NULL_TREE);
20292 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20293 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20294 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20299 /* Given type ARG, return std::initializer_list<ARG>. */
20304 tree std_init_list = namespace_binding
20305 (get_identifier ("initializer_list"), std_node);
20307 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20309 error ("deducing from brace-enclosed initializer list requires "
20310 "#include <initializer_list>");
20311 return error_mark_node;
20313 argvec = make_tree_vec (1);
20314 TREE_VEC_ELT (argvec, 0) = arg;
20315 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20316 NULL_TREE, 0, tf_warning_or_error);
20319 /* Replace auto in TYPE with std::initializer_list<auto>. */
20322 listify_autos (tree type, tree auto_node)
20324 tree init_auto = listify (auto_node);
20325 tree argvec = make_tree_vec (1);
20326 TREE_VEC_ELT (argvec, 0) = init_auto;
20327 if (processing_template_decl)
20328 argvec = add_to_template_args (current_template_args (), argvec);
20329 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20332 /* walk_tree helper for do_auto_deduction. */
20335 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20338 /* Is this a variable with the type we're looking for? */
20340 && TREE_TYPE (*tp) == type)
20346 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20347 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20350 do_auto_deduction (tree type, tree init, tree auto_node)
20352 tree parms, tparms, targs;
20357 if (processing_template_decl
20358 && (TREE_TYPE (init) == NULL_TREE
20359 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20360 /* Not enough information to try this yet. */
20363 /* The name of the object being declared shall not appear in the
20364 initializer expression. */
20365 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20368 error ("variable %q#D with %<auto%> type used in its own "
20369 "initializer", decl);
20370 return error_mark_node;
20373 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20374 with either a new invented type template parameter U or, if the
20375 initializer is a braced-init-list (8.5.4), with
20376 std::initializer_list<U>. */
20377 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20378 type = listify_autos (type, auto_node);
20380 init = resolve_nondeduced_context (init);
20382 parms = build_tree_list (NULL_TREE, type);
20384 tparms = make_tree_vec (1);
20385 targs = make_tree_vec (1);
20386 TREE_VEC_ELT (tparms, 0)
20387 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20388 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20389 DEDUCE_CALL, LOOKUP_NORMAL,
20390 /*explain_p=*/false);
20393 if (processing_template_decl)
20394 /* Try again at instantiation time. */
20396 if (type && type != error_mark_node)
20397 /* If type is error_mark_node a diagnostic must have been
20398 emitted by now. Also, having a mention to '<type error>'
20399 in the diagnostic is not really useful to the user. */
20400 error ("unable to deduce %qT from %qE", type, init);
20401 return error_mark_node;
20404 /* If the list of declarators contains more than one declarator, the type
20405 of each declared variable is determined as described above. If the
20406 type deduced for the template parameter U is not the same in each
20407 deduction, the program is ill-formed. */
20408 if (TREE_TYPE (auto_node)
20409 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20411 error ("inconsistent deduction for %qT: %qT and then %qT",
20412 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20413 return error_mark_node;
20415 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20417 if (processing_template_decl)
20418 targs = add_to_template_args (current_template_args (), targs);
20419 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20422 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20426 splice_late_return_type (tree type, tree late_return_type)
20430 if (late_return_type == NULL_TREE)
20432 argvec = make_tree_vec (1);
20433 TREE_VEC_ELT (argvec, 0) = late_return_type;
20434 if (processing_template_parmlist)
20435 /* For a late-specified return type in a template type-parameter, we
20436 need to add a dummy argument level for its parmlist. */
20437 argvec = add_to_template_args
20438 (make_tree_vec (processing_template_parmlist), argvec);
20439 if (current_template_parms)
20440 argvec = add_to_template_args (current_template_args (), argvec);
20441 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20444 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20447 is_auto (const_tree type)
20449 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20450 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20456 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20457 appear as a type-specifier for the declaration in question, we don't
20458 have to look through the whole type. */
20461 type_uses_auto (tree type)
20463 enum tree_code code;
20464 if (is_auto (type))
20467 code = TREE_CODE (type);
20469 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20470 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20471 || code == METHOD_TYPE || code == ARRAY_TYPE)
20472 return type_uses_auto (TREE_TYPE (type));
20474 if (TYPE_PTRMEMFUNC_P (type))
20475 return type_uses_auto (TREE_TYPE (TREE_TYPE
20476 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20481 /* For a given template T, return the vector of typedefs referenced
20482 in T for which access check is needed at T instantiation time.
20483 T is either a FUNCTION_DECL or a RECORD_TYPE.
20484 Those typedefs were added to T by the function
20485 append_type_to_template_for_access_check. */
20487 VEC(qualified_typedef_usage_t,gc)*
20488 get_types_needing_access_check (tree t)
20491 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20493 if (!t || t == error_mark_node)
20496 if (!(ti = get_template_info (t)))
20499 if (CLASS_TYPE_P (t)
20500 || TREE_CODE (t) == FUNCTION_DECL)
20502 if (!TI_TEMPLATE (ti))
20505 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20511 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20512 tied to T. That list of typedefs will be access checked at
20513 T instantiation time.
20514 T is either a FUNCTION_DECL or a RECORD_TYPE.
20515 TYPE_DECL is a TYPE_DECL node representing a typedef.
20516 SCOPE is the scope through which TYPE_DECL is accessed.
20517 LOCATION is the location of the usage point of TYPE_DECL.
20519 This function is a subroutine of
20520 append_type_to_template_for_access_check. */
20523 append_type_to_template_for_access_check_1 (tree t,
20526 location_t location)
20528 qualified_typedef_usage_t typedef_usage;
20531 if (!t || t == error_mark_node)
20534 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20535 || CLASS_TYPE_P (t))
20537 && TREE_CODE (type_decl) == TYPE_DECL
20540 if (!(ti = get_template_info (t)))
20543 gcc_assert (TI_TEMPLATE (ti));
20545 typedef_usage.typedef_decl = type_decl;
20546 typedef_usage.context = scope;
20547 typedef_usage.locus = location;
20549 VEC_safe_push (qualified_typedef_usage_t, gc,
20550 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20554 /* Append TYPE_DECL to the template TEMPL.
20555 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20556 At TEMPL instanciation time, TYPE_DECL will be checked to see
20557 if it can be accessed through SCOPE.
20558 LOCATION is the location of the usage point of TYPE_DECL.
20560 e.g. consider the following code snippet:
20567 template<class U> struct S
20569 C::myint mi; // <-- usage point of the typedef C::myint
20574 At S<char> instantiation time, we need to check the access of C::myint
20575 In other words, we need to check the access of the myint typedef through
20576 the C scope. For that purpose, this function will add the myint typedef
20577 and the scope C through which its being accessed to a list of typedefs
20578 tied to the template S. That list will be walked at template instantiation
20579 time and access check performed on each typedefs it contains.
20580 Note that this particular code snippet should yield an error because
20581 myint is private to C. */
20584 append_type_to_template_for_access_check (tree templ,
20587 location_t location)
20589 qualified_typedef_usage_t *iter;
20592 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20594 /* Make sure we don't append the type to the template twice. */
20595 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20596 get_types_needing_access_check (templ),
20598 if (iter->typedef_decl == type_decl && scope == iter->context)
20601 append_type_to_template_for_access_check_1 (templ, type_decl,
20605 /* Set up the hash tables for template instantiations. */
20608 init_template_processing (void)
20610 decl_specializations = htab_create_ggc (37,
20611 hash_specialization,
20612 eq_specializations,
20614 type_specializations = htab_create_ggc (37,
20615 hash_specialization,
20616 eq_specializations,
20620 /* Print stats about the template hash tables for -fstats. */
20623 print_template_statistics (void)
20625 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20626 "%f collisions\n", (long) htab_size (decl_specializations),
20627 (long) htab_elements (decl_specializations),
20628 htab_collisions (decl_specializations));
20629 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20630 "%f collisions\n", (long) htab_size (type_specializations),
20631 (long) htab_elements (type_specializations),
20632 htab_collisions (type_specializations));
20635 #include "gt-cp-pt.h"