1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 enum template_base_result {
114 tbr_ambiguous_baseclass,
118 static void push_access_scope (tree);
119 static void pop_access_scope (tree);
120 static void push_deduction_access_scope (tree);
121 static void pop_deduction_access_scope (tree);
122 static bool resolve_overloaded_unification (tree, tree, tree, tree,
123 unification_kind_t, int,
125 static int try_one_overload (tree, tree, tree, tree, tree,
126 unification_kind_t, int, bool, bool);
127 static int unify (tree, tree, tree, tree, int, bool);
128 static void add_pending_template (tree);
129 static tree reopen_tinst_level (struct tinst_level *);
130 static tree tsubst_initializer_list (tree, tree);
131 static tree get_class_bindings (tree, tree, tree);
132 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
134 static void tsubst_enum (tree, tree, tree);
135 static tree add_to_template_args (tree, tree);
136 static tree add_outermost_template_args (tree, tree);
137 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
138 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
140 static int type_unification_real (tree, tree, tree, const tree *,
141 unsigned int, int, unification_kind_t, int,
143 static void note_template_header (int);
144 static tree convert_nontype_argument_function (tree, tree);
145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
146 static tree convert_template_argument (tree, tree, tree,
147 tsubst_flags_t, int, tree);
148 static int for_each_template_parm (tree, tree_fn_t, void*,
149 struct pointer_set_t*, bool);
150 static tree expand_template_argument_pack (tree);
151 static tree build_template_parm_index (int, int, int, int, tree, tree);
152 static bool inline_needs_template_parms (tree);
153 static void push_inline_template_parms_recursive (tree, int);
154 static tree retrieve_local_specialization (tree);
155 static void register_local_specialization (tree, tree);
156 static hashval_t hash_specialization (const void *p);
157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
158 static int mark_template_parm (tree, void *);
159 static int template_parm_this_level_p (tree, void *);
160 static tree tsubst_friend_function (tree, tree);
161 static tree tsubst_friend_class (tree, tree);
162 static int can_complete_type_without_circularity (tree);
163 static tree get_bindings (tree, tree, tree, bool);
164 static int template_decl_level (tree);
165 static int check_cv_quals_for_unify (int, tree, tree);
166 static void template_parm_level_and_index (tree, int*, int*);
167 static int unify_pack_expansion (tree, tree, tree,
168 tree, unification_kind_t, bool, bool);
169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
172 static void regenerate_decl_from_template (tree, tree);
173 static tree most_specialized_class (tree, tree, tsubst_flags_t);
174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
175 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
177 static bool check_specialization_scope (void);
178 static tree process_partial_specialization (tree);
179 static void set_current_access_from_decl (tree);
180 static enum template_base_result get_template_base (tree, tree, tree, tree,
182 static tree try_class_unification (tree, tree, tree, tree, bool);
183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
185 static bool template_template_parm_bindings_ok_p (tree, tree);
186 static int template_args_equal (tree, tree);
187 static void tsubst_default_arguments (tree);
188 static tree for_each_template_parm_r (tree *, int *, void *);
189 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
190 static void copy_default_args_to_explicit_spec (tree);
191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
192 static int eq_local_specializations (const void *, const void *);
193 static bool dependent_template_arg_p (tree);
194 static bool any_template_arguments_need_structural_equality_p (tree);
195 static bool dependent_type_p_r (tree);
196 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
197 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
198 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
199 static tree tsubst_decl (tree, tree, tsubst_flags_t);
200 static void perform_typedefs_access_check (tree tmpl, tree targs);
201 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
203 static tree listify (tree);
204 static tree listify_autos (tree, tree);
205 static tree template_parm_to_arg (tree t);
206 static bool arg_from_parm_pack_p (tree, tree);
207 static tree current_template_args (void);
208 static tree fixup_template_type_parm_type (tree, int);
209 static tree fixup_template_parm_index (tree, tree, int);
210 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
212 /* Make the current scope suitable for access checking when we are
213 processing T. T can be FUNCTION_DECL for instantiated function
214 template, or VAR_DECL for static member variable (need by
215 instantiate_decl). */
218 push_access_scope (tree t)
220 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
221 || TREE_CODE (t) == VAR_DECL);
223 if (DECL_FRIEND_CONTEXT (t))
224 push_nested_class (DECL_FRIEND_CONTEXT (t));
225 else if (DECL_CLASS_SCOPE_P (t))
226 push_nested_class (DECL_CONTEXT (t));
228 push_to_top_level ();
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 saved_access_scope = tree_cons
233 (NULL_TREE, current_function_decl, saved_access_scope);
234 current_function_decl = t;
238 /* Restore the scope set up by push_access_scope. T is the node we
242 pop_access_scope (tree t)
244 if (TREE_CODE (t) == FUNCTION_DECL)
246 current_function_decl = TREE_VALUE (saved_access_scope);
247 saved_access_scope = TREE_CHAIN (saved_access_scope);
250 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
253 pop_from_top_level ();
256 /* Do any processing required when DECL (a member template
257 declaration) is finished. Returns the TEMPLATE_DECL corresponding
258 to DECL, unless it is a specialization, in which case the DECL
259 itself is returned. */
262 finish_member_template_decl (tree decl)
264 if (decl == error_mark_node)
265 return error_mark_node;
267 gcc_assert (DECL_P (decl));
269 if (TREE_CODE (decl) == TYPE_DECL)
273 type = TREE_TYPE (decl);
274 if (type == error_mark_node)
275 return error_mark_node;
276 if (MAYBE_CLASS_TYPE_P (type)
277 && CLASSTYPE_TEMPLATE_INFO (type)
278 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
280 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
281 check_member_template (tmpl);
286 else if (TREE_CODE (decl) == FIELD_DECL)
287 error ("data member %qD cannot be a member template", decl);
288 else if (DECL_TEMPLATE_INFO (decl))
290 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
292 check_member_template (DECL_TI_TEMPLATE (decl));
293 return DECL_TI_TEMPLATE (decl);
299 error ("invalid member template declaration %qD", decl);
301 return error_mark_node;
304 /* Create a template info node. */
307 build_template_info (tree template_decl, tree template_args)
309 tree result = make_node (TEMPLATE_INFO);
310 TI_TEMPLATE (result) = template_decl;
311 TI_ARGS (result) = template_args;
315 /* Return the template info node corresponding to T, whatever T is. */
318 get_template_info (const_tree t)
320 tree tinfo = NULL_TREE;
322 if (!t || t == error_mark_node)
325 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
326 tinfo = DECL_TEMPLATE_INFO (t);
328 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
331 if (TAGGED_TYPE_P (t))
332 tinfo = TYPE_TEMPLATE_INFO (t);
333 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
334 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
339 /* Returns the template nesting level of the indicated class TYPE.
349 A<T>::B<U> has depth two, while A<T> has depth one.
350 Both A<T>::B<int> and A<int>::B<U> have depth one, if
351 they are instantiations, not specializations.
353 This function is guaranteed to return 0 if passed NULL_TREE so
354 that, for example, `template_class_depth (current_class_type)' is
358 template_class_depth (tree type)
363 type && TREE_CODE (type) != NAMESPACE_DECL;
364 type = (TREE_CODE (type) == FUNCTION_DECL)
365 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
367 tree tinfo = get_template_info (type);
369 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
370 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
377 /* Subroutine of maybe_begin_member_template_processing.
378 Returns true if processing DECL needs us to push template parms. */
381 inline_needs_template_parms (tree decl)
383 if (! DECL_TEMPLATE_INFO (decl))
386 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
387 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
390 /* Subroutine of maybe_begin_member_template_processing.
391 Push the template parms in PARMS, starting from LEVELS steps into the
392 chain, and ending at the beginning, since template parms are listed
396 push_inline_template_parms_recursive (tree parmlist, int levels)
398 tree parms = TREE_VALUE (parmlist);
402 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
404 ++processing_template_decl;
405 current_template_parms
406 = tree_cons (size_int (processing_template_decl),
407 parms, current_template_parms);
408 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
410 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
412 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
414 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
416 if (parm == error_mark_node)
419 gcc_assert (DECL_P (parm));
421 switch (TREE_CODE (parm))
430 /* Make a CONST_DECL as is done in process_template_parm.
431 It is ugly that we recreate this here; the original
432 version built in process_template_parm is no longer
434 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
435 CONST_DECL, DECL_NAME (parm),
437 DECL_ARTIFICIAL (decl) = 1;
438 TREE_CONSTANT (decl) = 1;
439 TREE_READONLY (decl) = 1;
440 DECL_INITIAL (decl) = DECL_INITIAL (parm);
441 SET_DECL_TEMPLATE_PARM_P (decl);
452 /* Restore the template parameter context for a member template or
453 a friend template defined in a class definition. */
456 maybe_begin_member_template_processing (tree decl)
461 if (inline_needs_template_parms (decl))
463 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
464 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
466 if (DECL_TEMPLATE_SPECIALIZATION (decl))
469 parms = TREE_CHAIN (parms);
472 push_inline_template_parms_recursive (parms, levels);
475 /* Remember how many levels of template parameters we pushed so that
476 we can pop them later. */
477 VEC_safe_push (int, heap, inline_parm_levels, levels);
480 /* Undo the effects of maybe_begin_member_template_processing. */
483 maybe_end_member_template_processing (void)
488 if (VEC_length (int, inline_parm_levels) == 0)
491 last = VEC_pop (int, inline_parm_levels);
492 for (i = 0; i < last; ++i)
494 --processing_template_decl;
495 current_template_parms = TREE_CHAIN (current_template_parms);
500 /* Return a new template argument vector which contains all of ARGS,
501 but has as its innermost set of arguments the EXTRA_ARGS. */
504 add_to_template_args (tree args, tree extra_args)
511 if (args == NULL_TREE || extra_args == error_mark_node)
514 extra_depth = TMPL_ARGS_DEPTH (extra_args);
515 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
517 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
518 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
520 for (j = 1; j <= extra_depth; ++j, ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
526 /* Like add_to_template_args, but only the outermost ARGS are added to
527 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
528 (EXTRA_ARGS) levels are added. This function is used to combine
529 the template arguments from a partial instantiation with the
530 template arguments used to attain the full instantiation from the
531 partial instantiation. */
534 add_outermost_template_args (tree args, tree extra_args)
538 /* If there are more levels of EXTRA_ARGS than there are ARGS,
539 something very fishy is going on. */
540 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
542 /* If *all* the new arguments will be the EXTRA_ARGS, just return
544 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
547 /* For the moment, we make ARGS look like it contains fewer levels. */
548 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
550 new_args = add_to_template_args (args, extra_args);
552 /* Now, we restore ARGS to its full dimensions. */
553 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
558 /* Return the N levels of innermost template arguments from the ARGS. */
561 get_innermost_template_args (tree args, int n)
569 /* If N is 1, just return the innermost set of template arguments. */
571 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
573 /* If we're not removing anything, just return the arguments we were
575 extra_levels = TMPL_ARGS_DEPTH (args) - n;
576 gcc_assert (extra_levels >= 0);
577 if (extra_levels == 0)
580 /* Make a new set of arguments, not containing the outer arguments. */
581 new_args = make_tree_vec (n);
582 for (i = 1; i <= n; ++i)
583 SET_TMPL_ARGS_LEVEL (new_args, i,
584 TMPL_ARGS_LEVEL (args, i + extra_levels));
589 /* The inverse of get_innermost_template_args: Return all but the innermost
590 EXTRA_LEVELS levels of template arguments from the ARGS. */
593 strip_innermost_template_args (tree args, int extra_levels)
596 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
601 /* If N is 1, just return the outermost set of template arguments. */
603 return TMPL_ARGS_LEVEL (args, 1);
605 /* If we're not removing anything, just return the arguments we were
607 gcc_assert (extra_levels >= 0);
608 if (extra_levels == 0)
611 /* Make a new set of arguments, not containing the inner arguments. */
612 new_args = make_tree_vec (n);
613 for (i = 1; i <= n; ++i)
614 SET_TMPL_ARGS_LEVEL (new_args, i,
615 TMPL_ARGS_LEVEL (args, i));
620 /* We've got a template header coming up; push to a new level for storing
624 begin_template_parm_list (void)
626 /* We use a non-tag-transparent scope here, which causes pushtag to
627 put tags in this scope, rather than in the enclosing class or
628 namespace scope. This is the right thing, since we want
629 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
630 global template class, push_template_decl handles putting the
631 TEMPLATE_DECL into top-level scope. For a nested template class,
634 template <class T> struct S1 {
635 template <class T> struct S2 {};
638 pushtag contains special code to call pushdecl_with_scope on the
639 TEMPLATE_DECL for S2. */
640 begin_scope (sk_template_parms, NULL);
641 ++processing_template_decl;
642 ++processing_template_parmlist;
643 note_template_header (0);
646 /* This routine is called when a specialization is declared. If it is
647 invalid to declare a specialization here, an error is reported and
648 false is returned, otherwise this routine will return true. */
651 check_specialization_scope (void)
653 tree scope = current_scope ();
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template
664 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
666 error ("explicit specialization in non-namespace scope %qD", scope);
672 In an explicit specialization declaration for a member of a class
673 template or a member template that appears in namespace scope,
674 the member template and some of its enclosing class templates may
675 remain unspecialized, except that the declaration shall not
676 explicitly specialize a class member template if its enclosing
677 class templates are not explicitly specialized as well. */
678 if (current_template_parms)
680 error ("enclosing class templates are not explicitly specialized");
687 /* We've just seen template <>. */
690 begin_specialization (void)
692 begin_scope (sk_template_spec, NULL);
693 note_template_header (1);
694 return check_specialization_scope ();
697 /* Called at then end of processing a declaration preceded by
701 end_specialization (void)
704 reset_specialization ();
707 /* Any template <>'s that we have seen thus far are not referring to a
708 function specialization. */
711 reset_specialization (void)
713 processing_specialization = 0;
714 template_header_count = 0;
717 /* We've just seen a template header. If SPECIALIZATION is nonzero,
718 it was of the form template <>. */
721 note_template_header (int specialization)
723 processing_specialization = specialization;
724 template_header_count++;
727 /* We're beginning an explicit instantiation. */
730 begin_explicit_instantiation (void)
732 gcc_assert (!processing_explicit_instantiation);
733 processing_explicit_instantiation = true;
738 end_explicit_instantiation (void)
740 gcc_assert (processing_explicit_instantiation);
741 processing_explicit_instantiation = false;
744 /* An explicit specialization or partial specialization TMPL is being
745 declared. Check that the namespace in which the specialization is
746 occurring is permissible. Returns false iff it is invalid to
747 specialize TMPL in the current namespace. */
750 check_specialization_namespace (tree tmpl)
752 tree tpl_ns = decl_namespace_context (tmpl);
756 An explicit specialization shall be declared in the namespace of
757 which the template is a member, or, for member templates, in the
758 namespace of which the enclosing class or enclosing class
759 template is a member. An explicit specialization of a member
760 function, member class or static data member of a class template
761 shall be declared in the namespace of which the class template is
763 if (current_scope() != DECL_CONTEXT (tmpl)
764 && !at_namespace_scope_p ())
766 error ("specialization of %qD must appear at namespace scope", tmpl);
769 if (is_associated_namespace (current_namespace, tpl_ns))
770 /* Same or super-using namespace. */
774 permerror (input_location, "specialization of %qD in different namespace", tmpl);
775 permerror (input_location, " from definition of %q+#D", tmpl);
780 /* SPEC is an explicit instantiation. Check that it is valid to
781 perform this explicit instantiation in the current namespace. */
784 check_explicit_instantiation_namespace (tree spec)
788 /* DR 275: An explicit instantiation shall appear in an enclosing
789 namespace of its template. */
790 ns = decl_namespace_context (spec);
791 if (!is_ancestor (current_namespace, ns))
792 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
793 "(which does not enclose namespace %qD)",
794 spec, current_namespace, ns);
797 /* The TYPE is being declared. If it is a template type, that means it
798 is a partial specialization. Do appropriate error-checking. */
801 maybe_process_partial_specialization (tree type)
805 if (type == error_mark_node)
806 return error_mark_node;
808 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
810 error ("name of class shadows template template parameter %qD",
812 return error_mark_node;
815 context = TYPE_CONTEXT (type);
817 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
819 /* This is for ordinary explicit specialization and partial
820 specialization of a template class such as:
822 template <> class C<int>;
826 template <class T> class C<T*>;
828 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
830 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
831 && !COMPLETE_TYPE_P (type))
833 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
834 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
835 if (processing_template_decl)
837 if (push_template_decl (TYPE_MAIN_DECL (type))
839 return error_mark_node;
842 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
843 error ("specialization of %qT after instantiation", type);
845 else if (CLASS_TYPE_P (type)
846 && !CLASSTYPE_USE_TEMPLATE (type)
847 && CLASSTYPE_TEMPLATE_INFO (type)
848 && context && CLASS_TYPE_P (context)
849 && CLASSTYPE_TEMPLATE_INFO (context))
851 /* This is for an explicit specialization of member class
852 template according to [temp.expl.spec/18]:
854 template <> template <class U> class C<int>::D;
856 The context `C<int>' must be an implicit instantiation.
857 Otherwise this is just a member class template declared
860 template <> class C<int> { template <class U> class D; };
861 template <> template <class U> class C<int>::D;
863 In the first case, `C<int>::D' is a specialization of `C<T>::D'
864 while in the second case, `C<int>::D' is a primary template
865 and `C<T>::D' may not exist. */
867 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
868 && !COMPLETE_TYPE_P (type))
871 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
873 if (current_namespace
874 != decl_namespace_context (tmpl))
876 permerror (input_location, "specializing %q#T in different namespace", type);
877 permerror (input_location, " from definition of %q+#D", tmpl);
880 /* Check for invalid specialization after instantiation:
882 template <> template <> class C<int>::D<int>;
883 template <> template <class U> class C<int>::D; */
885 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
886 t; t = TREE_CHAIN (t))
888 tree inst = TREE_VALUE (t);
889 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
891 /* We already have a full specialization of this partial
892 instantiation. Reassign it to the new member
893 specialization template. */
898 elt.tmpl = most_general_template (tmpl);
899 elt.args = CLASSTYPE_TI_ARGS (inst);
902 htab_remove_elt (type_specializations, &elt);
905 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
907 slot = htab_find_slot (type_specializations, &elt, INSERT);
908 entry = ggc_alloc_spec_entry ();
912 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
913 /* But if we've had an implicit instantiation, that's a
914 problem ([temp.expl.spec]/6). */
915 error ("specialization %qT after instantiation %qT",
919 /* Mark TYPE as a specialization. And as a result, we only
920 have one level of template argument for the innermost
922 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
923 CLASSTYPE_TI_ARGS (type)
924 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
927 else if (processing_specialization)
929 /* Someday C++0x may allow for enum template specialization. */
930 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
931 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
932 pedwarn (input_location, OPT_pedantic, "template specialization "
933 "of %qD not allowed by ISO C++", type);
936 error ("explicit specialization of non-template %qT", type);
937 return error_mark_node;
944 /* Returns nonzero if we can optimize the retrieval of specializations
945 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
946 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
949 optimize_specialization_lookup_p (tree tmpl)
951 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
952 && DECL_CLASS_SCOPE_P (tmpl)
953 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
955 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
956 /* The optimized lookup depends on the fact that the
957 template arguments for the member function template apply
958 purely to the containing class, which is not true if the
959 containing class is an explicit or partial
961 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
962 && !DECL_MEMBER_TEMPLATE_P (tmpl)
963 && !DECL_CONV_FN_P (tmpl)
964 /* It is possible to have a template that is not a member
965 template and is not a member of a template class:
967 template <typename T>
968 struct S { friend A::f(); };
970 Here, the friend function is a template, but the context does
971 not have template information. The optimized lookup relies
972 on having ARGS be the template arguments for both the class
973 and the function template. */
974 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
977 /* Retrieve the specialization (in the sense of [temp.spec] - a
978 specialization is either an instantiation or an explicit
979 specialization) of TMPL for the given template ARGS. If there is
980 no such specialization, return NULL_TREE. The ARGS are a vector of
981 arguments, or a vector of vectors of arguments, in the case of
982 templates with more than one level of parameters.
984 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
985 then we search for a partial specialization matching ARGS. This
986 parameter is ignored if TMPL is not a class template. */
989 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
991 if (args == error_mark_node)
994 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
996 /* There should be as many levels of arguments as there are
997 levels of parameters. */
998 gcc_assert (TMPL_ARGS_DEPTH (args)
999 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1001 if (optimize_specialization_lookup_p (tmpl))
1003 tree class_template;
1004 tree class_specialization;
1005 VEC(tree,gc) *methods;
1009 /* The template arguments actually apply to the containing
1010 class. Find the class specialization with those
1012 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1013 class_specialization
1014 = retrieve_specialization (class_template, args, 0);
1015 if (!class_specialization)
1017 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1018 for the specialization. */
1019 idx = class_method_index_for_fn (class_specialization, tmpl);
1022 /* Iterate through the methods with the indicated name, looking
1023 for the one that has an instance of TMPL. */
1024 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1025 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1027 tree fn = OVL_CURRENT (fns);
1028 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1029 /* using-declarations can add base methods to the method vec,
1030 and we don't want those here. */
1031 && DECL_CONTEXT (fn) == class_specialization)
1040 htab_t specializations;
1044 elt.spec = NULL_TREE;
1046 if (DECL_CLASS_TEMPLATE_P (tmpl))
1047 specializations = type_specializations;
1049 specializations = decl_specializations;
1052 hash = hash_specialization (&elt);
1053 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1061 /* Like retrieve_specialization, but for local declarations. */
1064 retrieve_local_specialization (tree tmpl)
1068 if (local_specializations == NULL)
1071 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1072 htab_hash_pointer (tmpl));
1073 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1076 /* Returns nonzero iff DECL is a specialization of TMPL. */
1079 is_specialization_of (tree decl, tree tmpl)
1083 if (TREE_CODE (decl) == FUNCTION_DECL)
1087 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1093 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1095 for (t = TREE_TYPE (decl);
1097 t = CLASSTYPE_USE_TEMPLATE (t)
1098 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1099 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1106 /* Returns nonzero iff DECL is a specialization of friend declaration
1107 FRIEND_DECL according to [temp.friend]. */
1110 is_specialization_of_friend (tree decl, tree friend_decl)
1112 bool need_template = true;
1115 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1116 || TREE_CODE (decl) == TYPE_DECL);
1118 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1119 of a template class, we want to check if DECL is a specialization
1121 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1122 && DECL_TEMPLATE_INFO (friend_decl)
1123 && !DECL_USE_TEMPLATE (friend_decl))
1125 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1126 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1127 need_template = false;
1129 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1130 && !PRIMARY_TEMPLATE_P (friend_decl))
1131 need_template = false;
1133 /* There is nothing to do if this is not a template friend. */
1134 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1137 if (is_specialization_of (decl, friend_decl))
1141 A member of a class template may be declared to be a friend of a
1142 non-template class. In this case, the corresponding member of
1143 every specialization of the class template is a friend of the
1144 class granting friendship.
1146 For example, given a template friend declaration
1148 template <class T> friend void A<T>::f();
1150 the member function below is considered a friend
1152 template <> struct A<int> {
1156 For this type of template friend, TEMPLATE_DEPTH below will be
1157 nonzero. To determine if DECL is a friend of FRIEND, we first
1158 check if the enclosing class is a specialization of another. */
1160 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1162 && DECL_CLASS_SCOPE_P (decl)
1163 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1164 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1166 /* Next, we check the members themselves. In order to handle
1167 a few tricky cases, such as when FRIEND_DECL's are
1169 template <class T> friend void A<T>::g(T t);
1170 template <class T> template <T t> friend void A<T>::h();
1174 void A<int>::g(int);
1175 template <int> void A<int>::h();
1177 we need to figure out ARGS, the template arguments from
1178 the context of DECL. This is required for template substitution
1179 of `T' in the function parameter of `g' and template parameter
1180 of `h' in the above examples. Here ARGS corresponds to `int'. */
1182 tree context = DECL_CONTEXT (decl);
1183 tree args = NULL_TREE;
1184 int current_depth = 0;
1186 while (current_depth < template_depth)
1188 if (CLASSTYPE_TEMPLATE_INFO (context))
1190 if (current_depth == 0)
1191 args = TYPE_TI_ARGS (context);
1193 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1196 context = TYPE_CONTEXT (context);
1199 if (TREE_CODE (decl) == FUNCTION_DECL)
1204 tree friend_args_type;
1205 tree decl_args_type;
1207 /* Make sure that both DECL and FRIEND_DECL are templates or
1209 is_template = DECL_TEMPLATE_INFO (decl)
1210 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1211 if (need_template ^ is_template)
1213 else if (is_template)
1215 /* If both are templates, check template parameter list. */
1217 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1219 if (!comp_template_parms
1220 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1224 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1227 decl_type = TREE_TYPE (decl);
1229 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1230 tf_none, NULL_TREE);
1231 if (friend_type == error_mark_node)
1234 /* Check if return types match. */
1235 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1238 /* Check if function parameter types match, ignoring the
1239 `this' parameter. */
1240 friend_args_type = TYPE_ARG_TYPES (friend_type);
1241 decl_args_type = TYPE_ARG_TYPES (decl_type);
1242 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1243 friend_args_type = TREE_CHAIN (friend_args_type);
1244 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1245 decl_args_type = TREE_CHAIN (decl_args_type);
1247 return compparms (decl_args_type, friend_args_type);
1251 /* DECL is a TYPE_DECL */
1253 tree decl_type = TREE_TYPE (decl);
1255 /* Make sure that both DECL and FRIEND_DECL are templates or
1258 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1259 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1261 if (need_template ^ is_template)
1263 else if (is_template)
1266 /* If both are templates, check the name of the two
1267 TEMPLATE_DECL's first because is_friend didn't. */
1268 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1269 != DECL_NAME (friend_decl))
1272 /* Now check template parameter list. */
1274 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1276 return comp_template_parms
1277 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1281 return (DECL_NAME (decl)
1282 == DECL_NAME (friend_decl));
1288 /* Register the specialization SPEC as a specialization of TMPL with
1289 the indicated ARGS. IS_FRIEND indicates whether the specialization
1290 is actually just a friend declaration. Returns SPEC, or an
1291 equivalent prior declaration, if available. */
1294 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1301 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1303 if (TREE_CODE (spec) == FUNCTION_DECL
1304 && uses_template_parms (DECL_TI_ARGS (spec)))
1305 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1306 register it; we want the corresponding TEMPLATE_DECL instead.
1307 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1308 the more obvious `uses_template_parms (spec)' to avoid problems
1309 with default function arguments. In particular, given
1310 something like this:
1312 template <class T> void f(T t1, T t = T())
1314 the default argument expression is not substituted for in an
1315 instantiation unless and until it is actually needed. */
1318 if (optimize_specialization_lookup_p (tmpl))
1319 /* We don't put these specializations in the hash table, but we might
1320 want to give an error about a mismatch. */
1321 fn = retrieve_specialization (tmpl, args, 0);
1329 hash = hash_specialization (&elt);
1332 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1334 fn = ((spec_entry *) *slot)->spec;
1339 /* We can sometimes try to re-register a specialization that we've
1340 already got. In particular, regenerate_decl_from_template calls
1341 duplicate_decls which will update the specialization list. But,
1342 we'll still get called again here anyhow. It's more convenient
1343 to simply allow this than to try to prevent it. */
1346 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1348 if (DECL_TEMPLATE_INSTANTIATION (fn))
1350 if (DECL_ODR_USED (fn)
1351 || DECL_EXPLICIT_INSTANTIATION (fn))
1353 error ("specialization of %qD after instantiation",
1355 return error_mark_node;
1360 /* This situation should occur only if the first
1361 specialization is an implicit instantiation, the
1362 second is an explicit specialization, and the
1363 implicit instantiation has not yet been used. That
1364 situation can occur if we have implicitly
1365 instantiated a member function and then specialized
1368 We can also wind up here if a friend declaration that
1369 looked like an instantiation turns out to be a
1372 template <class T> void foo(T);
1373 class S { friend void foo<>(int) };
1374 template <> void foo(int);
1376 We transform the existing DECL in place so that any
1377 pointers to it become pointers to the updated
1380 If there was a definition for the template, but not
1381 for the specialization, we want this to look as if
1382 there were no definition, and vice versa. */
1383 DECL_INITIAL (fn) = NULL_TREE;
1384 duplicate_decls (spec, fn, is_friend);
1385 /* The call to duplicate_decls will have applied
1388 An explicit specialization of a function template
1389 is inline only if it is explicitly declared to be,
1390 and independently of whether its function template
1393 to the primary function; now copy the inline bits to
1394 the various clones. */
1395 FOR_EACH_CLONE (clone, fn)
1397 DECL_DECLARED_INLINE_P (clone)
1398 = DECL_DECLARED_INLINE_P (fn);
1399 DECL_SOURCE_LOCATION (clone)
1400 = DECL_SOURCE_LOCATION (fn);
1402 check_specialization_namespace (fn);
1407 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1409 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1410 /* Dup decl failed, but this is a new definition. Set the
1411 line number so any errors match this new
1413 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1419 return duplicate_decls (spec, fn, is_friend);
1421 /* A specialization must be declared in the same namespace as the
1422 template it is specializing. */
1423 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1424 && !check_specialization_namespace (tmpl))
1425 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1427 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */)
1429 spec_entry *entry = ggc_alloc_spec_entry ();
1430 gcc_assert (tmpl && args && spec);
1433 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1434 && PRIMARY_TEMPLATE_P (tmpl)
1435 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1436 /* TMPL is a forward declaration of a template function; keep a list
1437 of all specializations in case we need to reassign them to a friend
1438 template later in tsubst_friend_function. */
1439 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1440 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1446 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1447 TMPL and ARGS members, ignores SPEC. */
1450 eq_specializations (const void *p1, const void *p2)
1452 const spec_entry *e1 = (const spec_entry *)p1;
1453 const spec_entry *e2 = (const spec_entry *)p2;
1455 return (e1->tmpl == e2->tmpl
1456 && comp_template_args (e1->args, e2->args));
1459 /* Returns a hash for a template TMPL and template arguments ARGS. */
1462 hash_tmpl_and_args (tree tmpl, tree args)
1464 hashval_t val = DECL_UID (tmpl);
1465 return iterative_hash_template_arg (args, val);
1468 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1472 hash_specialization (const void *p)
1474 const spec_entry *e = (const spec_entry *)p;
1475 return hash_tmpl_and_args (e->tmpl, e->args);
1478 /* Recursively calculate a hash value for a template argument ARG, for use
1479 in the hash tables of template specializations. */
1482 iterative_hash_template_arg (tree arg, hashval_t val)
1484 unsigned HOST_WIDE_INT i;
1485 enum tree_code code;
1488 if (arg == NULL_TREE)
1489 return iterative_hash_object (arg, val);
1494 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1495 /* We can get one of these when re-hashing a previous entry in the middle
1496 of substituting into a pack expansion. Just look through it. */
1497 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1499 code = TREE_CODE (arg);
1500 tclass = TREE_CODE_CLASS (code);
1502 val = iterative_hash_object (code, val);
1509 case IDENTIFIER_NODE:
1510 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1514 int i, len = TREE_VEC_LENGTH (arg);
1515 for (i = 0; i < len; ++i)
1516 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1520 case TYPE_PACK_EXPANSION:
1521 case EXPR_PACK_EXPANSION:
1522 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1524 case TYPE_ARGUMENT_PACK:
1525 case NONTYPE_ARGUMENT_PACK:
1526 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1529 for (; arg; arg = TREE_CHAIN (arg))
1530 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1534 for (; arg; arg = OVL_NEXT (arg))
1535 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1541 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1543 val = iterative_hash_template_arg (field, val);
1544 val = iterative_hash_template_arg (value, val);
1550 if (!DECL_ARTIFICIAL (arg))
1552 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1553 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1555 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1558 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1561 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1562 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1564 case TEMPLATE_PARM_INDEX:
1565 val = iterative_hash_template_arg
1566 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1567 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1568 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1571 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1572 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1573 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1576 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1578 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1582 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1583 code = TREE_CODE (TREE_OPERAND (arg, 1));
1584 val = iterative_hash_object (code, val);
1585 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1588 /* A lambda can't appear in a template arg, but don't crash on
1590 gcc_assert (seen_error ());
1594 case IMPLICIT_CONV_EXPR:
1595 case STATIC_CAST_EXPR:
1596 case REINTERPRET_CAST_EXPR:
1597 case CONST_CAST_EXPR:
1598 case DYNAMIC_CAST_EXPR:
1600 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1601 /* Now hash operands as usual. */
1611 if (TYPE_CANONICAL (arg))
1612 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1614 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1615 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1616 /* Otherwise just compare the types during lookup. */
1619 case tcc_declaration:
1621 return iterative_hash_expr (arg, val);
1624 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1626 unsigned n = cp_tree_operand_length (arg);
1627 for (i = 0; i < n; ++i)
1628 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1636 /* Unregister the specialization SPEC as a specialization of TMPL.
1637 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1638 if the SPEC was listed as a specialization of TMPL.
1640 Note that SPEC has been ggc_freed, so we can't look inside it. */
1643 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1648 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1649 elt.args = TI_ARGS (tinfo);
1650 elt.spec = NULL_TREE;
1652 entry = (spec_entry *) htab_find (decl_specializations, &elt);
1655 gcc_assert (entry->spec == spec || entry->spec == new_spec);
1656 gcc_assert (new_spec != NULL_TREE);
1657 entry->spec = new_spec;
1664 /* Compare an entry in the local specializations hash table P1 (which
1665 is really a pointer to a TREE_LIST) with P2 (which is really a
1669 eq_local_specializations (const void *p1, const void *p2)
1671 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1674 /* Hash P1, an entry in the local specializations table. */
1677 hash_local_specialization (const void* p1)
1679 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1682 /* Like register_specialization, but for local declarations. We are
1683 registering SPEC, an instantiation of TMPL. */
1686 register_local_specialization (tree spec, tree tmpl)
1690 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1691 htab_hash_pointer (tmpl), INSERT);
1692 *slot = build_tree_list (spec, tmpl);
1695 /* TYPE is a class type. Returns true if TYPE is an explicitly
1696 specialized class. */
1699 explicit_class_specialization_p (tree type)
1701 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1703 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1706 /* Print the list of functions at FNS, going through all the overloads
1707 for each element of the list. Alternatively, FNS can not be a
1708 TREE_LIST, in which case it will be printed together with all the
1711 MORE and *STR should respectively be FALSE and NULL when the function
1712 is called from the outside. They are used internally on recursive
1713 calls. print_candidates manages the two parameters and leaves NULL
1714 in *STR when it ends. */
1717 print_candidates_1 (tree fns, bool more, const char **str)
1720 char *spaces = NULL;
1722 for (fn = fns; fn; fn = OVL_NEXT (fn))
1723 if (TREE_CODE (fn) == TREE_LIST)
1725 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1726 print_candidates_1 (TREE_VALUE (fn2),
1727 TREE_CHAIN (fn2) || more, str);
1733 /* Pick the prefix string. */
1734 if (!more && !OVL_NEXT (fns))
1736 error ("candidate is: %+#D", OVL_CURRENT (fn));
1740 *str = _("candidates are:");
1741 spaces = get_spaces (*str);
1743 error ("%s %+#D", *str, OVL_CURRENT (fn));
1744 *str = spaces ? spaces : *str;
1754 /* Print the list of candidate FNS in an error message. FNS can also
1755 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1758 print_candidates (tree fns)
1760 const char *str = NULL;
1761 print_candidates_1 (fns, false, &str);
1762 gcc_assert (str == NULL);
1765 /* Returns the template (one of the functions given by TEMPLATE_ID)
1766 which can be specialized to match the indicated DECL with the
1767 explicit template args given in TEMPLATE_ID. The DECL may be
1768 NULL_TREE if none is available. In that case, the functions in
1769 TEMPLATE_ID are non-members.
1771 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1772 specialization of a member template.
1774 The TEMPLATE_COUNT is the number of references to qualifying
1775 template classes that appeared in the name of the function. See
1776 check_explicit_specialization for a more accurate description.
1778 TSK indicates what kind of template declaration (if any) is being
1779 declared. TSK_TEMPLATE indicates that the declaration given by
1780 DECL, though a FUNCTION_DECL, has template parameters, and is
1781 therefore a template function.
1783 The template args (those explicitly specified and those deduced)
1784 are output in a newly created vector *TARGS_OUT.
1786 If it is impossible to determine the result, an error message is
1787 issued. The error_mark_node is returned to indicate failure. */
1790 determine_specialization (tree template_id,
1793 int need_member_template,
1799 tree explicit_targs;
1800 tree candidates = NULL_TREE;
1801 /* A TREE_LIST of templates of which DECL may be a specialization.
1802 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1803 corresponding TREE_PURPOSE is the set of template arguments that,
1804 when used to instantiate the template, would produce a function
1805 with the signature of DECL. */
1806 tree templates = NULL_TREE;
1808 cp_binding_level *b;
1810 *targs_out = NULL_TREE;
1812 if (template_id == error_mark_node || decl == error_mark_node)
1813 return error_mark_node;
1815 fns = TREE_OPERAND (template_id, 0);
1816 explicit_targs = TREE_OPERAND (template_id, 1);
1818 if (fns == error_mark_node)
1819 return error_mark_node;
1821 /* Check for baselinks. */
1822 if (BASELINK_P (fns))
1823 fns = BASELINK_FUNCTIONS (fns);
1825 if (!is_overloaded_fn (fns))
1827 error ("%qD is not a function template", fns);
1828 return error_mark_node;
1831 /* Count the number of template headers specified for this
1834 for (b = current_binding_level;
1835 b->kind == sk_template_parms;
1839 for (; fns; fns = OVL_NEXT (fns))
1841 tree fn = OVL_CURRENT (fns);
1843 if (TREE_CODE (fn) == TEMPLATE_DECL)
1845 tree decl_arg_types;
1848 /* In case of explicit specialization, we need to check if
1849 the number of template headers appearing in the specialization
1850 is correct. This is usually done in check_explicit_specialization,
1851 but the check done there cannot be exhaustive when specializing
1852 member functions. Consider the following code:
1854 template <> void A<int>::f(int);
1855 template <> template <> void A<int>::f(int);
1857 Assuming that A<int> is not itself an explicit specialization
1858 already, the first line specializes "f" which is a non-template
1859 member function, whilst the second line specializes "f" which
1860 is a template member function. So both lines are syntactically
1861 correct, and check_explicit_specialization does not reject
1864 Here, we can do better, as we are matching the specialization
1865 against the declarations. We count the number of template
1866 headers, and we check if they match TEMPLATE_COUNT + 1
1867 (TEMPLATE_COUNT is the number of qualifying template classes,
1868 plus there must be another header for the member template
1871 Notice that if header_count is zero, this is not a
1872 specialization but rather a template instantiation, so there
1873 is no check we can perform here. */
1874 if (header_count && header_count != template_count + 1)
1877 /* Check that the number of template arguments at the
1878 innermost level for DECL is the same as for FN. */
1879 if (current_binding_level->kind == sk_template_parms
1880 && !current_binding_level->explicit_spec_p
1881 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1882 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1883 (current_template_parms))))
1886 /* DECL might be a specialization of FN. */
1887 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1888 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1890 /* For a non-static member function, we need to make sure
1891 that the const qualification is the same. Since
1892 get_bindings does not try to merge the "this" parameter,
1893 we must do the comparison explicitly. */
1894 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1895 && !same_type_p (TREE_VALUE (fn_arg_types),
1896 TREE_VALUE (decl_arg_types)))
1899 /* Skip the "this" parameter and, for constructors of
1900 classes with virtual bases, the VTT parameter. A
1901 full specialization of a constructor will have a VTT
1902 parameter, but a template never will. */
1904 = skip_artificial_parms_for (decl, decl_arg_types);
1906 = skip_artificial_parms_for (fn, fn_arg_types);
1908 /* Check that the number of function parameters matches.
1910 template <class T> void f(int i = 0);
1911 template <> void f<int>();
1912 The specialization f<int> is invalid but is not caught
1913 by get_bindings below. */
1914 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1917 /* Function templates cannot be specializations; there are
1918 no partial specializations of functions. Therefore, if
1919 the type of DECL does not match FN, there is no
1921 if (tsk == tsk_template)
1923 if (compparms (fn_arg_types, decl_arg_types))
1924 candidates = tree_cons (NULL_TREE, fn, candidates);
1928 /* See whether this function might be a specialization of this
1930 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1933 /* We cannot deduce template arguments that when used to
1934 specialize TMPL will produce DECL. */
1937 /* Save this template, and the arguments deduced. */
1938 templates = tree_cons (targs, fn, templates);
1940 else if (need_member_template)
1941 /* FN is an ordinary member function, and we need a
1942 specialization of a member template. */
1944 else if (TREE_CODE (fn) != FUNCTION_DECL)
1945 /* We can get IDENTIFIER_NODEs here in certain erroneous
1948 else if (!DECL_FUNCTION_MEMBER_P (fn))
1949 /* This is just an ordinary non-member function. Nothing can
1950 be a specialization of that. */
1952 else if (DECL_ARTIFICIAL (fn))
1953 /* Cannot specialize functions that are created implicitly. */
1957 tree decl_arg_types;
1959 /* This is an ordinary member function. However, since
1960 we're here, we can assume it's enclosing class is a
1961 template class. For example,
1963 template <typename T> struct S { void f(); };
1964 template <> void S<int>::f() {}
1966 Here, S<int>::f is a non-template, but S<int> is a
1967 template class. If FN has the same type as DECL, we
1968 might be in business. */
1970 if (!DECL_TEMPLATE_INFO (fn))
1971 /* Its enclosing class is an explicit specialization
1972 of a template class. This is not a candidate. */
1975 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1976 TREE_TYPE (TREE_TYPE (fn))))
1977 /* The return types differ. */
1980 /* Adjust the type of DECL in case FN is a static member. */
1981 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1982 if (DECL_STATIC_FUNCTION_P (fn)
1983 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1984 decl_arg_types = TREE_CHAIN (decl_arg_types);
1986 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1989 candidates = tree_cons (NULL_TREE, fn, candidates);
1993 if (templates && TREE_CHAIN (templates))
1999 It is possible for a specialization with a given function
2000 signature to be instantiated from more than one function
2001 template. In such cases, explicit specification of the
2002 template arguments must be used to uniquely identify the
2003 function template specialization being specialized.
2005 Note that here, there's no suggestion that we're supposed to
2006 determine which of the candidate templates is most
2007 specialized. However, we, also have:
2011 Partial ordering of overloaded function template
2012 declarations is used in the following contexts to select
2013 the function template to which a function template
2014 specialization refers:
2016 -- when an explicit specialization refers to a function
2019 So, we do use the partial ordering rules, at least for now.
2020 This extension can only serve to make invalid programs valid,
2021 so it's safe. And, there is strong anecdotal evidence that
2022 the committee intended the partial ordering rules to apply;
2023 the EDG front end has that behavior, and John Spicer claims
2024 that the committee simply forgot to delete the wording in
2025 [temp.expl.spec]. */
2026 tree tmpl = most_specialized_instantiation (templates);
2027 if (tmpl != error_mark_node)
2030 TREE_CHAIN (templates) = NULL_TREE;
2034 if (templates == NULL_TREE && candidates == NULL_TREE)
2036 error ("template-id %qD for %q+D does not match any template "
2037 "declaration", template_id, decl);
2038 if (header_count && header_count != template_count + 1)
2039 inform (input_location, "saw %d %<template<>%>, need %d for "
2040 "specializing a member function template",
2041 header_count, template_count + 1);
2042 return error_mark_node;
2044 else if ((templates && TREE_CHAIN (templates))
2045 || (candidates && TREE_CHAIN (candidates))
2046 || (templates && candidates))
2048 error ("ambiguous template specialization %qD for %q+D",
2050 candidates = chainon (candidates, templates);
2051 print_candidates (candidates);
2052 return error_mark_node;
2055 /* We have one, and exactly one, match. */
2058 tree fn = TREE_VALUE (candidates);
2059 *targs_out = copy_node (DECL_TI_ARGS (fn));
2060 /* DECL is a re-declaration or partial instantiation of a template
2062 if (TREE_CODE (fn) == TEMPLATE_DECL)
2064 /* It was a specialization of an ordinary member function in a
2066 return DECL_TI_TEMPLATE (fn);
2069 /* It was a specialization of a template. */
2070 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2071 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2073 *targs_out = copy_node (targs);
2074 SET_TMPL_ARGS_LEVEL (*targs_out,
2075 TMPL_ARGS_DEPTH (*targs_out),
2076 TREE_PURPOSE (templates));
2079 *targs_out = TREE_PURPOSE (templates);
2080 return TREE_VALUE (templates);
2083 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2084 but with the default argument values filled in from those in the
2088 copy_default_args_to_explicit_spec_1 (tree spec_types,
2091 tree new_spec_types;
2096 if (spec_types == void_list_node)
2097 return void_list_node;
2099 /* Substitute into the rest of the list. */
2101 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2102 TREE_CHAIN (tmpl_types));
2104 /* Add the default argument for this parameter. */
2105 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2106 TREE_VALUE (spec_types),
2110 /* DECL is an explicit specialization. Replicate default arguments
2111 from the template it specializes. (That way, code like:
2113 template <class T> void f(T = 3);
2114 template <> void f(double);
2117 works, as required.) An alternative approach would be to look up
2118 the correct default arguments at the call-site, but this approach
2119 is consistent with how implicit instantiations are handled. */
2122 copy_default_args_to_explicit_spec (tree decl)
2127 tree new_spec_types;
2131 tree object_type = NULL_TREE;
2132 tree in_charge = NULL_TREE;
2133 tree vtt = NULL_TREE;
2135 /* See if there's anything we need to do. */
2136 tmpl = DECL_TI_TEMPLATE (decl);
2137 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2138 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2139 if (TREE_PURPOSE (t))
2144 old_type = TREE_TYPE (decl);
2145 spec_types = TYPE_ARG_TYPES (old_type);
2147 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2149 /* Remove the this pointer, but remember the object's type for
2151 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2152 spec_types = TREE_CHAIN (spec_types);
2153 tmpl_types = TREE_CHAIN (tmpl_types);
2155 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2157 /* DECL may contain more parameters than TMPL due to the extra
2158 in-charge parameter in constructors and destructors. */
2159 in_charge = spec_types;
2160 spec_types = TREE_CHAIN (spec_types);
2162 if (DECL_HAS_VTT_PARM_P (decl))
2165 spec_types = TREE_CHAIN (spec_types);
2169 /* Compute the merged default arguments. */
2171 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2173 /* Compute the new FUNCTION_TYPE. */
2177 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2182 /* Put the in-charge parameter back. */
2183 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2184 TREE_VALUE (in_charge),
2187 new_type = build_method_type_directly (object_type,
2188 TREE_TYPE (old_type),
2192 new_type = build_function_type (TREE_TYPE (old_type),
2194 new_type = cp_build_type_attribute_variant (new_type,
2195 TYPE_ATTRIBUTES (old_type));
2196 new_type = build_exception_variant (new_type,
2197 TYPE_RAISES_EXCEPTIONS (old_type));
2198 TREE_TYPE (decl) = new_type;
2201 /* Check to see if the function just declared, as indicated in
2202 DECLARATOR, and in DECL, is a specialization of a function
2203 template. We may also discover that the declaration is an explicit
2204 instantiation at this point.
2206 Returns DECL, or an equivalent declaration that should be used
2207 instead if all goes well. Issues an error message if something is
2208 amiss. Returns error_mark_node if the error is not easily
2211 FLAGS is a bitmask consisting of the following flags:
2213 2: The function has a definition.
2214 4: The function is a friend.
2216 The TEMPLATE_COUNT is the number of references to qualifying
2217 template classes that appeared in the name of the function. For
2220 template <class T> struct S { void f(); };
2223 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2224 classes are not counted in the TEMPLATE_COUNT, so that in
2226 template <class T> struct S {};
2227 template <> struct S<int> { void f(); }
2228 template <> void S<int>::f();
2230 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2231 invalid; there should be no template <>.)
2233 If the function is a specialization, it is marked as such via
2234 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2235 is set up correctly, and it is added to the list of specializations
2236 for that template. */
2239 check_explicit_specialization (tree declarator,
2244 int have_def = flags & 2;
2245 int is_friend = flags & 4;
2246 int specialization = 0;
2247 int explicit_instantiation = 0;
2248 int member_specialization = 0;
2249 tree ctype = DECL_CLASS_CONTEXT (decl);
2250 tree dname = DECL_NAME (decl);
2255 if (!processing_specialization)
2258 tsk = tsk_excessive_parms;
2261 tsk = current_tmpl_spec_kind (template_count);
2266 if (processing_specialization)
2269 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2271 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2274 /* This could be something like:
2276 template <class T> void f(T);
2277 class S { friend void f<>(int); } */
2281 /* This case handles bogus declarations like template <>
2282 template <class T> void f<int>(); */
2284 error ("template-id %qD in declaration of primary template",
2291 case tsk_invalid_member_spec:
2292 /* The error has already been reported in
2293 check_specialization_scope. */
2294 return error_mark_node;
2296 case tsk_invalid_expl_inst:
2297 error ("template parameter list used in explicit instantiation");
2303 error ("definition provided for explicit instantiation");
2305 explicit_instantiation = 1;
2308 case tsk_excessive_parms:
2309 case tsk_insufficient_parms:
2310 if (tsk == tsk_excessive_parms)
2311 error ("too many template parameter lists in declaration of %qD",
2313 else if (template_header_count)
2314 error("too few template parameter lists in declaration of %qD", decl);
2316 error("explicit specialization of %qD must be introduced by "
2317 "%<template <>%>", decl);
2321 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2323 member_specialization = 1;
2329 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2331 /* This case handles bogus declarations like template <>
2332 template <class T> void f<int>(); */
2334 if (uses_template_parms (declarator))
2335 error ("function template partial specialization %qD "
2336 "is not allowed", declarator);
2338 error ("template-id %qD in declaration of primary template",
2343 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2344 /* This is a specialization of a member template, without
2345 specialization the containing class. Something like:
2347 template <class T> struct S {
2348 template <class U> void f (U);
2350 template <> template <class U> void S<int>::f(U) {}
2352 That's a specialization -- but of the entire template. */
2360 if (specialization || member_specialization)
2362 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2363 for (; t; t = TREE_CHAIN (t))
2364 if (TREE_PURPOSE (t))
2366 permerror (input_location,
2367 "default argument specified in explicit specialization");
2372 if (specialization || member_specialization || explicit_instantiation)
2374 tree tmpl = NULL_TREE;
2375 tree targs = NULL_TREE;
2377 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2378 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2382 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2387 /* If there is no class context, the explicit instantiation
2388 must be at namespace scope. */
2389 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2391 /* Find the namespace binding, using the declaration
2393 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2395 if (fns == error_mark_node || !is_overloaded_fn (fns))
2397 error ("%qD is not a template function", dname);
2398 fns = error_mark_node;
2402 tree fn = OVL_CURRENT (fns);
2403 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2404 CP_DECL_CONTEXT (fn)))
2405 error ("%qD is not declared in %qD",
2406 decl, current_namespace);
2410 declarator = lookup_template_function (fns, NULL_TREE);
2413 if (declarator == error_mark_node)
2414 return error_mark_node;
2416 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2418 if (!explicit_instantiation)
2419 /* A specialization in class scope. This is invalid,
2420 but the error will already have been flagged by
2421 check_specialization_scope. */
2422 return error_mark_node;
2425 /* It's not valid to write an explicit instantiation in
2428 class C { template void f(); }
2430 This case is caught by the parser. However, on
2433 template class C { void f(); };
2435 (which is invalid) we can get here. The error will be
2442 else if (ctype != NULL_TREE
2443 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2446 /* Find the list of functions in ctype that have the same
2447 name as the declared function. */
2448 tree name = TREE_OPERAND (declarator, 0);
2449 tree fns = NULL_TREE;
2452 if (constructor_name_p (name, ctype))
2454 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2456 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2457 : !CLASSTYPE_DESTRUCTORS (ctype))
2459 /* From [temp.expl.spec]:
2461 If such an explicit specialization for the member
2462 of a class template names an implicitly-declared
2463 special member function (clause _special_), the
2464 program is ill-formed.
2466 Similar language is found in [temp.explicit]. */
2467 error ("specialization of implicitly-declared special member function");
2468 return error_mark_node;
2471 name = is_constructor ? ctor_identifier : dtor_identifier;
2474 if (!DECL_CONV_FN_P (decl))
2476 idx = lookup_fnfields_1 (ctype, name);
2478 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2482 VEC(tree,gc) *methods;
2485 /* For a type-conversion operator, we cannot do a
2486 name-based lookup. We might be looking for `operator
2487 int' which will be a specialization of `operator T'.
2488 So, we find *all* the conversion operators, and then
2489 select from them. */
2492 methods = CLASSTYPE_METHOD_VEC (ctype);
2494 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2495 VEC_iterate (tree, methods, idx, ovl);
2498 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2499 /* There are no more conversion functions. */
2502 /* Glue all these conversion functions together
2503 with those we already have. */
2504 for (; ovl; ovl = OVL_NEXT (ovl))
2505 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2509 if (fns == NULL_TREE)
2511 error ("no member function %qD declared in %qT", name, ctype);
2512 return error_mark_node;
2515 TREE_OPERAND (declarator, 0) = fns;
2518 /* Figure out what exactly is being specialized at this point.
2519 Note that for an explicit instantiation, even one for a
2520 member function, we cannot tell apriori whether the
2521 instantiation is for a member template, or just a member
2522 function of a template class. Even if a member template is
2523 being instantiated, the member template arguments may be
2524 elided if they can be deduced from the rest of the
2526 tmpl = determine_specialization (declarator, decl,
2528 member_specialization,
2532 if (!tmpl || tmpl == error_mark_node)
2533 /* We couldn't figure out what this declaration was
2535 return error_mark_node;
2538 tree gen_tmpl = most_general_template (tmpl);
2540 if (explicit_instantiation)
2542 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2543 is done by do_decl_instantiation later. */
2545 int arg_depth = TMPL_ARGS_DEPTH (targs);
2546 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2548 if (arg_depth > parm_depth)
2550 /* If TMPL is not the most general template (for
2551 example, if TMPL is a friend template that is
2552 injected into namespace scope), then there will
2553 be too many levels of TARGS. Remove some of them
2558 new_targs = make_tree_vec (parm_depth);
2559 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2560 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2561 = TREE_VEC_ELT (targs, i);
2565 return instantiate_template (tmpl, targs, tf_error);
2568 /* If we thought that the DECL was a member function, but it
2569 turns out to be specializing a static member function,
2570 make DECL a static member function as well. */
2571 if (DECL_STATIC_FUNCTION_P (tmpl)
2572 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2573 revert_static_member_fn (decl);
2575 /* If this is a specialization of a member template of a
2576 template class, we want to return the TEMPLATE_DECL, not
2577 the specialization of it. */
2578 if (tsk == tsk_template)
2580 tree result = DECL_TEMPLATE_RESULT (tmpl);
2581 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2582 DECL_INITIAL (result) = NULL_TREE;
2586 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2587 DECL_SOURCE_LOCATION (result)
2588 = DECL_SOURCE_LOCATION (decl);
2589 /* We want to use the argument list specified in the
2590 definition, not in the original declaration. */
2591 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2592 for (parm = DECL_ARGUMENTS (result); parm;
2593 parm = DECL_CHAIN (parm))
2594 DECL_CONTEXT (parm) = result;
2596 return register_specialization (tmpl, gen_tmpl, targs,
2600 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2601 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2603 /* Inherit default function arguments from the template
2604 DECL is specializing. */
2605 copy_default_args_to_explicit_spec (decl);
2607 /* This specialization has the same protection as the
2608 template it specializes. */
2609 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2610 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2612 /* 7.1.1-1 [dcl.stc]
2614 A storage-class-specifier shall not be specified in an
2615 explicit specialization...
2617 The parser rejects these, so unless action is taken here,
2618 explicit function specializations will always appear with
2621 The action recommended by the C++ CWG in response to C++
2622 defect report 605 is to make the storage class and linkage
2623 of the explicit specialization match the templated function:
2625 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2627 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2629 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2630 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2632 /* This specialization has the same linkage and visibility as
2633 the function template it specializes. */
2634 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2635 if (! TREE_PUBLIC (decl))
2637 DECL_INTERFACE_KNOWN (decl) = 1;
2638 DECL_NOT_REALLY_EXTERN (decl) = 1;
2640 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2641 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2643 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2644 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2648 /* If DECL is a friend declaration, declared using an
2649 unqualified name, the namespace associated with DECL may
2650 have been set incorrectly. For example, in:
2652 template <typename T> void f(T);
2654 struct S { friend void f<int>(int); }
2657 we will have set the DECL_CONTEXT for the friend
2658 declaration to N, rather than to the global namespace. */
2659 if (DECL_NAMESPACE_SCOPE_P (decl))
2660 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2662 if (is_friend && !have_def)
2663 /* This is not really a declaration of a specialization.
2664 It's just the name of an instantiation. But, it's not
2665 a request for an instantiation, either. */
2666 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2667 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2668 /* This is indeed a specialization. In case of constructors
2669 and destructors, we need in-charge and not-in-charge
2670 versions in V3 ABI. */
2671 clone_function_decl (decl, /*update_method_vec_p=*/0);
2673 /* Register this specialization so that we can find it
2675 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2682 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2683 parameters. These are represented in the same format used for
2684 DECL_TEMPLATE_PARMS. */
2687 comp_template_parms (const_tree parms1, const_tree parms2)
2692 if (parms1 == parms2)
2695 for (p1 = parms1, p2 = parms2;
2696 p1 != NULL_TREE && p2 != NULL_TREE;
2697 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2699 tree t1 = TREE_VALUE (p1);
2700 tree t2 = TREE_VALUE (p2);
2703 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2704 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2706 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2709 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2711 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2712 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2714 /* If either of the template parameters are invalid, assume
2715 they match for the sake of error recovery. */
2716 if (parm1 == error_mark_node || parm2 == error_mark_node)
2719 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2722 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2723 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2724 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2726 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2731 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2732 /* One set of parameters has more parameters lists than the
2739 /* Determine whether PARM is a parameter pack. */
2742 template_parameter_pack_p (const_tree parm)
2744 /* Determine if we have a non-type template parameter pack. */
2745 if (TREE_CODE (parm) == PARM_DECL)
2746 return (DECL_TEMPLATE_PARM_P (parm)
2747 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2748 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2749 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2751 /* If this is a list of template parameters, we could get a
2752 TYPE_DECL or a TEMPLATE_DECL. */
2753 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2754 parm = TREE_TYPE (parm);
2756 /* Otherwise it must be a type template parameter. */
2757 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2758 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2759 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2762 /* Determine if T is a function parameter pack. */
2765 function_parameter_pack_p (const_tree t)
2767 if (t && TREE_CODE (t) == PARM_DECL)
2768 return FUNCTION_PARAMETER_PACK_P (t);
2772 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2773 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2776 get_function_template_decl (const_tree primary_func_tmpl_inst)
2778 if (! primary_func_tmpl_inst
2779 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2780 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2783 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2786 /* Return true iff the function parameter PARAM_DECL was expanded
2787 from the function parameter pack PACK. */
2790 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2792 if (DECL_ARTIFICIAL (param_decl)
2793 || !function_parameter_pack_p (pack))
2796 /* The parameter pack and its pack arguments have the same
2798 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2801 /* Determine whether ARGS describes a variadic template args list,
2802 i.e., one that is terminated by a template argument pack. */
2805 template_args_variadic_p (tree args)
2810 if (args == NULL_TREE)
2813 args = INNERMOST_TEMPLATE_ARGS (args);
2814 nargs = TREE_VEC_LENGTH (args);
2819 last_parm = TREE_VEC_ELT (args, nargs - 1);
2821 return ARGUMENT_PACK_P (last_parm);
2824 /* Generate a new name for the parameter pack name NAME (an
2825 IDENTIFIER_NODE) that incorporates its */
2828 make_ith_pack_parameter_name (tree name, int i)
2830 /* Munge the name to include the parameter index. */
2831 #define NUMBUF_LEN 128
2832 char numbuf[NUMBUF_LEN];
2836 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2837 newname_len = IDENTIFIER_LENGTH (name)
2838 + strlen (numbuf) + 2;
2839 newname = (char*)alloca (newname_len);
2840 snprintf (newname, newname_len,
2841 "%s#%i", IDENTIFIER_POINTER (name), i);
2842 return get_identifier (newname);
2845 /* Return true if T is a primary function
2846 or class template instantiation. */
2849 primary_template_instantiation_p (const_tree t)
2854 if (TREE_CODE (t) == FUNCTION_DECL)
2855 return DECL_LANG_SPECIFIC (t)
2856 && DECL_TEMPLATE_INSTANTIATION (t)
2857 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2858 else if (CLASS_TYPE_P (t))
2859 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2860 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2864 /* Return true if PARM is a template template parameter. */
2867 template_template_parameter_p (const_tree parm)
2869 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2872 /* Return the template parameters of T if T is a
2873 primary template instantiation, NULL otherwise. */
2876 get_primary_template_innermost_parameters (const_tree t)
2878 tree parms = NULL, template_info = NULL;
2880 if ((template_info = get_template_info (t))
2881 && primary_template_instantiation_p (t))
2882 parms = INNERMOST_TEMPLATE_PARMS
2883 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2888 /* Return the template parameters of the LEVELth level from the full list
2889 of template parameters PARMS. */
2892 get_template_parms_at_level (tree parms, int level)
2896 || TREE_CODE (parms) != TREE_LIST
2897 || level > TMPL_PARMS_DEPTH (parms))
2900 for (p = parms; p; p = TREE_CHAIN (p))
2901 if (TMPL_PARMS_DEPTH (p) == level)
2907 /* Returns the template arguments of T if T is a template instantiation,
2911 get_template_innermost_arguments (const_tree t)
2913 tree args = NULL, template_info = NULL;
2915 if ((template_info = get_template_info (t))
2916 && TI_ARGS (template_info))
2917 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2922 /* Return the argument pack elements of T if T is a template argument pack,
2926 get_template_argument_pack_elems (const_tree t)
2928 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2929 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2932 return ARGUMENT_PACK_ARGS (t);
2935 /* Structure used to track the progress of find_parameter_packs_r. */
2936 struct find_parameter_pack_data
2938 /* TREE_LIST that will contain all of the parameter packs found by
2940 tree* parameter_packs;
2942 /* Set of AST nodes that have been visited by the traversal. */
2943 struct pointer_set_t *visited;
2946 /* Identifies all of the argument packs that occur in a template
2947 argument and appends them to the TREE_LIST inside DATA, which is a
2948 find_parameter_pack_data structure. This is a subroutine of
2949 make_pack_expansion and uses_parameter_packs. */
2951 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2954 struct find_parameter_pack_data* ppd =
2955 (struct find_parameter_pack_data*)data;
2956 bool parameter_pack_p = false;
2958 /* Identify whether this is a parameter pack or not. */
2959 switch (TREE_CODE (t))
2961 case TEMPLATE_PARM_INDEX:
2962 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2963 parameter_pack_p = true;
2966 case TEMPLATE_TYPE_PARM:
2967 t = TYPE_MAIN_VARIANT (t);
2968 case TEMPLATE_TEMPLATE_PARM:
2969 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2970 parameter_pack_p = true;
2974 if (FUNCTION_PARAMETER_PACK_P (t))
2976 /* We don't want to walk into the type of a PARM_DECL,
2977 because we don't want to see the type parameter pack. */
2979 parameter_pack_p = true;
2984 parameter_pack_p = true;
2987 /* Not a parameter pack. */
2991 if (parameter_pack_p)
2993 /* Add this parameter pack to the list. */
2994 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2998 cp_walk_tree (&TYPE_CONTEXT (t),
2999 &find_parameter_packs_r, ppd, ppd->visited);
3001 /* This switch statement will return immediately if we don't find a
3003 switch (TREE_CODE (t))
3005 case TEMPLATE_PARM_INDEX:
3008 case BOUND_TEMPLATE_TEMPLATE_PARM:
3009 /* Check the template itself. */
3010 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3011 &find_parameter_packs_r, ppd, ppd->visited);
3012 /* Check the template arguments. */
3013 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3018 case TEMPLATE_TYPE_PARM:
3019 case TEMPLATE_TEMPLATE_PARM:
3026 if (TYPE_PTRMEMFUNC_P (t))
3032 if (TYPE_TEMPLATE_INFO (t))
3033 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3034 &find_parameter_packs_r, ppd, ppd->visited);
3041 cp_walk_tree (&TREE_TYPE (t),
3042 &find_parameter_packs_r, ppd, ppd->visited);
3046 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3051 case TYPE_PACK_EXPANSION:
3052 case EXPR_PACK_EXPANSION:
3057 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3062 case IDENTIFIER_NODE:
3063 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3075 /* Determines if the expression or type T uses any parameter packs. */
3077 uses_parameter_packs (tree t)
3079 tree parameter_packs = NULL_TREE;
3080 struct find_parameter_pack_data ppd;
3081 ppd.parameter_packs = ¶meter_packs;
3082 ppd.visited = pointer_set_create ();
3083 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3084 pointer_set_destroy (ppd.visited);
3085 return parameter_packs != NULL_TREE;
3088 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3089 representation a base-class initializer into a parameter pack
3090 expansion. If all goes well, the resulting node will be an
3091 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3094 make_pack_expansion (tree arg)
3097 tree parameter_packs = NULL_TREE;
3098 bool for_types = false;
3099 struct find_parameter_pack_data ppd;
3101 if (!arg || arg == error_mark_node)
3104 if (TREE_CODE (arg) == TREE_LIST)
3106 /* The only time we will see a TREE_LIST here is for a base
3107 class initializer. In this case, the TREE_PURPOSE will be a
3108 _TYPE node (representing the base class expansion we're
3109 initializing) and the TREE_VALUE will be a TREE_LIST
3110 containing the initialization arguments.
3112 The resulting expansion looks somewhat different from most
3113 expansions. Rather than returning just one _EXPANSION, we
3114 return a TREE_LIST whose TREE_PURPOSE is a
3115 TYPE_PACK_EXPANSION containing the bases that will be
3116 initialized. The TREE_VALUE will be identical to the
3117 original TREE_VALUE, which is a list of arguments that will
3118 be passed to each base. We do not introduce any new pack
3119 expansion nodes into the TREE_VALUE (although it is possible
3120 that some already exist), because the TREE_PURPOSE and
3121 TREE_VALUE all need to be expanded together with the same
3122 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3123 resulting TREE_PURPOSE will mention the parameter packs in
3124 both the bases and the arguments to the bases. */
3127 tree parameter_packs = NULL_TREE;
3129 /* Determine which parameter packs will be used by the base
3131 ppd.visited = pointer_set_create ();
3132 ppd.parameter_packs = ¶meter_packs;
3133 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3136 if (parameter_packs == NULL_TREE)
3138 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3139 pointer_set_destroy (ppd.visited);
3140 return error_mark_node;
3143 if (TREE_VALUE (arg) != void_type_node)
3145 /* Collect the sets of parameter packs used in each of the
3146 initialization arguments. */
3147 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3149 /* Determine which parameter packs will be expanded in this
3151 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3156 pointer_set_destroy (ppd.visited);
3158 /* Create the pack expansion type for the base type. */
3159 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3160 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3161 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3163 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3164 they will rarely be compared to anything. */
3165 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3167 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3170 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3173 /* Build the PACK_EXPANSION_* node. */
3175 ? cxx_make_type (TYPE_PACK_EXPANSION)
3176 : make_node (EXPR_PACK_EXPANSION);
3177 SET_PACK_EXPANSION_PATTERN (result, arg);
3178 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3180 /* Propagate type and const-expression information. */
3181 TREE_TYPE (result) = TREE_TYPE (arg);
3182 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3185 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3186 they will rarely be compared to anything. */
3187 SET_TYPE_STRUCTURAL_EQUALITY (result);
3189 /* Determine which parameter packs will be expanded. */
3190 ppd.parameter_packs = ¶meter_packs;
3191 ppd.visited = pointer_set_create ();
3192 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3193 pointer_set_destroy (ppd.visited);
3195 /* Make sure we found some parameter packs. */
3196 if (parameter_packs == NULL_TREE)
3199 error ("expansion pattern %<%T%> contains no argument packs", arg);
3201 error ("expansion pattern %<%E%> contains no argument packs", arg);
3202 return error_mark_node;
3204 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3209 /* Checks T for any "bare" parameter packs, which have not yet been
3210 expanded, and issues an error if any are found. This operation can
3211 only be done on full expressions or types (e.g., an expression
3212 statement, "if" condition, etc.), because we could have expressions like:
3214 foo(f(g(h(args)))...)
3216 where "args" is a parameter pack. check_for_bare_parameter_packs
3217 should not be called for the subexpressions args, h(args),
3218 g(h(args)), or f(g(h(args))), because we would produce erroneous
3221 Returns TRUE and emits an error if there were bare parameter packs,
3222 returns FALSE otherwise. */
3224 check_for_bare_parameter_packs (tree t)
3226 tree parameter_packs = NULL_TREE;
3227 struct find_parameter_pack_data ppd;
3229 if (!processing_template_decl || !t || t == error_mark_node)
3232 if (TREE_CODE (t) == TYPE_DECL)
3235 ppd.parameter_packs = ¶meter_packs;
3236 ppd.visited = pointer_set_create ();
3237 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3238 pointer_set_destroy (ppd.visited);
3240 if (parameter_packs)
3242 error ("parameter packs not expanded with %<...%>:");
3243 while (parameter_packs)
3245 tree pack = TREE_VALUE (parameter_packs);
3246 tree name = NULL_TREE;
3248 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3249 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3250 name = TYPE_NAME (pack);
3251 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3252 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3254 name = DECL_NAME (pack);
3257 inform (input_location, " %qD", name);
3259 inform (input_location, " <anonymous>");
3261 parameter_packs = TREE_CHAIN (parameter_packs);
3270 /* Expand any parameter packs that occur in the template arguments in
3273 expand_template_argument_pack (tree args)
3275 tree result_args = NULL_TREE;
3276 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3277 int num_result_args = -1;
3278 int non_default_args_count = -1;
3280 /* First, determine if we need to expand anything, and the number of
3281 slots we'll need. */
3282 for (in_arg = 0; in_arg < nargs; ++in_arg)
3284 tree arg = TREE_VEC_ELT (args, in_arg);
3285 if (arg == NULL_TREE)
3287 if (ARGUMENT_PACK_P (arg))
3289 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3290 if (num_result_args < 0)
3291 num_result_args = in_arg + num_packed;
3293 num_result_args += num_packed;
3297 if (num_result_args >= 0)
3302 /* If no expansion is necessary, we're done. */
3303 if (num_result_args < 0)
3306 /* Expand arguments. */
3307 result_args = make_tree_vec (num_result_args);
3308 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3309 non_default_args_count =
3310 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3311 for (in_arg = 0; in_arg < nargs; ++in_arg)
3313 tree arg = TREE_VEC_ELT (args, in_arg);
3314 if (ARGUMENT_PACK_P (arg))
3316 tree packed = ARGUMENT_PACK_ARGS (arg);
3317 int i, num_packed = TREE_VEC_LENGTH (packed);
3318 for (i = 0; i < num_packed; ++i, ++out_arg)
3319 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3320 if (non_default_args_count > 0)
3321 non_default_args_count += num_packed;
3325 TREE_VEC_ELT (result_args, out_arg) = arg;
3329 if (non_default_args_count >= 0)
3330 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3334 /* Checks if DECL shadows a template parameter.
3336 [temp.local]: A template-parameter shall not be redeclared within its
3337 scope (including nested scopes).
3339 Emits an error and returns TRUE if the DECL shadows a parameter,
3340 returns FALSE otherwise. */
3343 check_template_shadow (tree decl)
3347 /* If we're not in a template, we can't possibly shadow a template
3349 if (!current_template_parms)
3352 /* Figure out what we're shadowing. */
3353 if (TREE_CODE (decl) == OVERLOAD)
3354 decl = OVL_CURRENT (decl);
3355 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3357 /* If there's no previous binding for this name, we're not shadowing
3358 anything, let alone a template parameter. */
3362 /* If we're not shadowing a template parameter, we're done. Note
3363 that OLDDECL might be an OVERLOAD (or perhaps even an
3364 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3366 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3369 /* We check for decl != olddecl to avoid bogus errors for using a
3370 name inside a class. We check TPFI to avoid duplicate errors for
3371 inline member templates. */
3373 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3376 error ("declaration of %q+#D", decl);
3377 error (" shadows template parm %q+#D", olddecl);
3381 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3382 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3383 template parameters. */
3386 build_template_parm_index (int index,
3393 tree t = make_node (TEMPLATE_PARM_INDEX);
3394 TEMPLATE_PARM_IDX (t) = index;
3395 TEMPLATE_PARM_LEVEL (t) = level;
3396 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3397 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3398 TEMPLATE_PARM_DECL (t) = decl;
3399 TREE_TYPE (t) = type;
3400 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3401 TREE_READONLY (t) = TREE_READONLY (decl);
3406 /* Find the canonical type parameter for the given template type
3407 parameter. Returns the canonical type parameter, which may be TYPE
3408 if no such parameter existed. */
3411 canonical_type_parameter (tree type)
3414 int idx = TEMPLATE_TYPE_IDX (type);
3415 if (!canonical_template_parms)
3416 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3418 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3419 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3421 list = VEC_index (tree, canonical_template_parms, idx);
3422 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3423 list = TREE_CHAIN (list);
3426 return TREE_VALUE (list);
3429 VEC_replace(tree, canonical_template_parms, idx,
3430 tree_cons (NULL_TREE, type,
3431 VEC_index (tree, canonical_template_parms, idx)));
3436 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3437 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3438 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3439 new one is created. */
3442 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3443 tsubst_flags_t complain)
3445 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3446 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3447 != TEMPLATE_PARM_LEVEL (index) - levels)
3448 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3450 tree orig_decl = TEMPLATE_PARM_DECL (index);
3453 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3454 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3455 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3456 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3457 DECL_ARTIFICIAL (decl) = 1;
3458 SET_DECL_TEMPLATE_PARM_P (decl);
3460 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3461 TEMPLATE_PARM_LEVEL (index) - levels,
3462 TEMPLATE_PARM_ORIG_LEVEL (index),
3463 TEMPLATE_PARM_NUM_SIBLINGS (index),
3465 TEMPLATE_PARM_DESCENDANTS (index) = t;
3466 TEMPLATE_PARM_PARAMETER_PACK (t)
3467 = TEMPLATE_PARM_PARAMETER_PACK (index);
3469 /* Template template parameters need this. */
3470 if (TREE_CODE (decl) == TEMPLATE_DECL)
3471 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3472 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3476 return TEMPLATE_PARM_DESCENDANTS (index);
3479 /* Process information from new template parameter PARM and append it
3480 to the LIST being built. This new parameter is a non-type
3481 parameter iff IS_NON_TYPE is true. This new parameter is a
3482 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3483 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3484 parameter list PARM belongs to. This is used used to create a
3485 proper canonical type for the type of PARM that is to be created,
3486 iff PARM is a type. If the size is not known, this parameter shall
3490 process_template_parm (tree list, location_t parm_loc, tree parm,
3491 bool is_non_type, bool is_parameter_pack,
3492 unsigned num_template_parms)
3499 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3500 defval = TREE_PURPOSE (parm);
3504 tree p = tree_last (list);
3506 if (p && TREE_VALUE (p) != error_mark_node)
3509 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3510 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3512 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3522 parm = TREE_VALUE (parm);
3524 SET_DECL_TEMPLATE_PARM_P (parm);
3526 if (TREE_TYPE (parm) == error_mark_node)
3528 err_parm_list = build_tree_list (defval, parm);
3529 TREE_VALUE (err_parm_list) = error_mark_node;
3530 return chainon (list, err_parm_list);
3536 The top-level cv-qualifiers on the template-parameter are
3537 ignored when determining its type. */
3538 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3539 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3541 err_parm_list = build_tree_list (defval, parm);
3542 TREE_VALUE (err_parm_list) = error_mark_node;
3543 return chainon (list, err_parm_list);
3546 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3548 /* This template parameter is not a parameter pack, but it
3549 should be. Complain about "bare" parameter packs. */
3550 check_for_bare_parameter_packs (TREE_TYPE (parm));
3552 /* Recover by calling this a parameter pack. */
3553 is_parameter_pack = true;
3557 /* A template parameter is not modifiable. */
3558 TREE_CONSTANT (parm) = 1;
3559 TREE_READONLY (parm) = 1;
3560 decl = build_decl (parm_loc,
3561 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3562 TREE_CONSTANT (decl) = 1;
3563 TREE_READONLY (decl) = 1;
3564 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3565 = build_template_parm_index (idx, processing_template_decl,
3566 processing_template_decl,
3568 decl, TREE_TYPE (parm));
3570 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3571 = is_parameter_pack;
3576 parm = TREE_VALUE (TREE_VALUE (parm));
3578 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3580 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3581 /* This is for distinguishing between real templates and template
3582 template parameters */
3583 TREE_TYPE (parm) = t;
3584 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3589 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3590 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3591 decl = build_decl (parm_loc,
3592 TYPE_DECL, parm, t);
3595 TYPE_NAME (t) = decl;
3596 TYPE_STUB_DECL (t) = decl;
3598 TEMPLATE_TYPE_PARM_INDEX (t)
3599 = build_template_parm_index (idx, processing_template_decl,
3600 processing_template_decl,
3602 decl, TREE_TYPE (parm));
3603 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3604 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3606 DECL_ARTIFICIAL (decl) = 1;
3607 SET_DECL_TEMPLATE_PARM_P (decl);
3609 parm = build_tree_list (defval, parm);
3610 return chainon (list, parm);
3613 /* The end of a template parameter list has been reached. Process the
3614 tree list into a parameter vector, converting each parameter into a more
3615 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3619 end_template_parm_list (tree parms)
3623 tree saved_parmlist = make_tree_vec (list_length (parms));
3625 current_template_parms
3626 = tree_cons (size_int (processing_template_decl),
3627 saved_parmlist, current_template_parms);
3629 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3631 next = TREE_CHAIN (parm);
3632 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3633 TREE_CHAIN (parm) = NULL_TREE;
3636 --processing_template_parmlist;
3638 return saved_parmlist;
3641 /* Create a new type almost identical to TYPE but which has the
3642 following differences:
3644 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3645 template sibling parameters of T.
3647 2/ T has a new canonical type that matches the new number
3650 3/ From now on, T is going to be what lookups referring to the
3651 name of TYPE will return. No lookup should return TYPE anymore.
3653 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3655 This is a subroutine of fixup_template_parms. */
3658 fixup_template_type_parm_type (tree type, int num_parms)
3660 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3662 /* This is the decl which name is inserted into the symbol table for
3663 the template parm type. So whenever we lookup the type name, this
3664 is the DECL we get. */
3667 /* Do not fix up the type twice. */
3668 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3671 t = copy_type (type);
3672 decl = TYPE_NAME (t);
3674 TYPE_MAIN_VARIANT (t) = t;
3675 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3676 TYPE_POINTER_TO (t) = 0;
3677 TYPE_REFERENCE_TO (t) = 0;
3679 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3680 TEMPLATE_PARM_LEVEL (orig_idx),
3681 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3684 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3685 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3686 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3688 TYPE_STUB_DECL (t) = decl;
3689 TEMPLATE_TYPE_DECL (t) = decl;
3690 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3691 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3693 /* Update the type associated to the type name stored in the symbol
3694 table. Now, whenever the type name is looked up, the resulting
3695 type is properly fixed up. */
3696 TREE_TYPE (decl) = t;
3698 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3703 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3704 identical to I, but that is fixed up as to:
3706 1/ carry the number of sibling parms (NUM_PARMS) of the template
3707 parm represented by I.
3709 2/ replace all references to template parm types declared before I
3710 (in the same template parm list as I) by references to template
3711 parm types contained in ARGS. ARGS should contain the list of
3712 template parms that have been fixed up so far, in a form suitable
3713 to be passed to tsubst.
3715 This is a subroutine of fixup_template_parms. */
3718 fixup_template_parm_index (tree i, tree args, int num_parms)
3720 tree index, decl, type;
3723 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3724 /* Do not fix up the index twice. */
3725 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3728 decl = TEMPLATE_PARM_DECL (i);
3729 type = TREE_TYPE (decl);
3731 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3732 TEMPLATE_PARM_LEVEL (i),
3733 TEMPLATE_PARM_ORIG_LEVEL (i),
3737 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3738 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3740 type = tsubst (type, args, tf_none, NULL_TREE);
3742 TREE_TYPE (decl) = type;
3743 TREE_TYPE (index) = type;
3749 This is a subroutine of fixup_template_parms.
3751 It computes the canonical type of the type of the template
3752 parameter PARM_DESC and update all references to that type so that
3753 they use the newly computed canonical type. No access check is
3754 performed during the fixup. PARM_DESC is a TREE_LIST which
3755 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3756 default argument of the template parm if any. IDX is the index of
3757 the template parameter, starting at 0. NUM_PARMS is the number of
3758 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3759 TREE_VEC containing the full set of template parameters in a form
3760 suitable to be passed to substs functions as their ARGS
3761 argument. This is what current_template_args returns for a given
3762 template. The innermost vector of args in ARGLIST is the set of
3763 template parms that have been fixed up so far. This function adds
3764 the fixed up parameter into that vector. */
3767 fixup_template_parm (tree parm_desc,
3772 tree parm = TREE_VALUE (parm_desc);
3773 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3775 push_deferring_access_checks (dk_no_check);
3777 if (TREE_CODE (parm) == TYPE_DECL)
3779 /* PARM is a template type parameter. Fix up its type, add
3780 the fixed-up template parm to the vector of fixed-up
3781 template parms so far, and substitute the fixed-up
3782 template parms into the default argument of this
3785 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3786 TREE_TYPE (parm) = t;
3788 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3790 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3792 /* PARM is a template template parameter. This is going to
3794 tree tparms, targs, innermost_args, t;
3797 /* First, fix up the parms of the template template parm
3798 because the parms are involved in defining the new canonical
3799 type of the template template parm. */
3801 /* So we need to substitute the template parm types that have
3802 been fixed up so far into the template parms of this template
3803 template parm. E.g, consider this:
3805 template<class T, template<T u> class TT> class S;
3807 In this case we want to substitute T into the
3808 template parameters of TT.
3810 So let's walk the template parms of PARM here, and
3811 tsubst ARGLIST into into each of the template
3814 /* For this substitution we need to build the full set of
3815 template parameters and use that as arguments for the
3816 tsubsting function. */
3817 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3819 /* This will contain the innermost parms of PARM into which
3820 we have substituted so far. */
3821 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3822 targs = add_to_template_args (arglist, innermost_args);
3823 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3827 parameter = TREE_VEC_ELT (tparms, j);
3829 /* INNERMOST_ARGS needs to have at least the same number
3830 of elements as the index PARAMETER, ortherwise
3831 tsubsting into PARAMETER will result in partially
3832 instantiating it, reducing its tempate parm
3833 level. Let's tactically fill INNERMOST_ARGS for that
3835 TREE_VEC_ELT (innermost_args, j) =
3836 template_parm_to_arg (parameter);
3838 fixup_template_parm (parameter, j,
3839 TREE_VEC_LENGTH (tparms),
3843 /* Now fix up the type of the template template parm. */
3845 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3846 TREE_TYPE (parm) = t;
3848 TREE_VEC_ELT (fixedup_args, idx) =
3849 template_parm_to_arg (parm_desc);
3851 else if (TREE_CODE (parm) == PARM_DECL)
3853 /* PARM is a non-type template parameter. We need to:
3855 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3856 proper number of sibling parameters.
3858 * Make lookups of the template parameter return a reference
3859 to the fixed-up index. No lookup should return references
3860 to the former index anymore.
3862 * Substitute the template parms that got fixed up so far
3864 * into the type of PARM. */
3866 tree index = DECL_INITIAL (parm);
3868 /* PUSHED_DECL is the decl added to the symbol table with
3869 the name of the parameter. E,g:
3871 template<class T, T u> //#0
3872 auto my_function(T t) -> decltype(u); //#1
3874 Here, when looking up u at //#1, we get the decl of u
3875 resulting from the declaration in #0. This is what
3876 PUSHED_DECL is. We need to replace the reference to the
3877 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3878 fixed-up TEMPLATE_PARM_INDEX. */
3879 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3881 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3882 fixup the type of PUSHED_DECL as well and luckily
3883 fixup_template_parm_index does it for us too. */
3884 tree fixed_up_index =
3885 fixup_template_parm_index (index, arglist, num_parms);
3887 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3889 /* Add this fixed up PARM to the template parms we've fixed
3890 up so far and use that to substitute the fixed-up
3891 template parms into the type of PARM. */
3892 TREE_VEC_ELT (fixedup_args, idx) =
3893 template_parm_to_arg (parm_desc);
3894 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3895 tf_none, NULL_TREE);
3898 TREE_PURPOSE (parm_desc) =
3899 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3900 arglist, tf_none, parm);
3902 pop_deferring_access_checks ();
3905 /* Walk the current template parms and properly compute the canonical
3906 types of the dependent types created during
3907 cp_parser_template_parameter_list. */
3910 fixup_template_parms (void)
3917 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3918 if (parameter_vec == NULL_TREE)
3921 num_parms = TREE_VEC_LENGTH (parameter_vec);
3923 /* This vector contains the current innermost template parms that
3924 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3925 to be passed to tsubst* functions as their ARGS argument. */
3926 fixedup_args = make_tree_vec (num_parms);
3928 /* This vector contains the full set of template parms in a form
3929 suitable to be passed to substs functions as their ARGS
3931 arglist = current_template_args ();
3932 arglist = add_outermost_template_args (arglist, fixedup_args);
3934 /* Let's do the proper fixup now. */
3935 for (i = 0; i < num_parms; ++i)
3936 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3937 i, num_parms, arglist);
3940 /* end_template_decl is called after a template declaration is seen. */
3943 end_template_decl (void)
3945 reset_specialization ();
3947 if (! processing_template_decl)
3950 /* This matches the pushlevel in begin_template_parm_list. */
3953 --processing_template_decl;
3954 current_template_parms = TREE_CHAIN (current_template_parms);
3957 /* Takes a TREE_LIST representing a template parameter and convert it
3958 into an argument suitable to be passed to the type substitution
3959 functions. Note that If the TREE_LIST contains an error_mark
3960 node, the returned argument is error_mark_node. */
3963 template_parm_to_arg (tree t)
3967 || TREE_CODE (t) != TREE_LIST)
3970 if (error_operand_p (TREE_VALUE (t)))
3971 return error_mark_node;
3975 if (TREE_CODE (t) == TYPE_DECL
3976 || TREE_CODE (t) == TEMPLATE_DECL)
3980 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3982 /* Turn this argument into a TYPE_ARGUMENT_PACK
3983 with a single element, which expands T. */
3984 tree vec = make_tree_vec (1);
3985 #ifdef ENABLE_CHECKING
3986 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3987 (vec, TREE_VEC_LENGTH (vec));
3989 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3991 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3992 SET_ARGUMENT_PACK_ARGS (t, vec);
3997 t = DECL_INITIAL (t);
3999 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4001 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4002 with a single element, which expands T. */
4003 tree vec = make_tree_vec (1);
4004 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4005 #ifdef ENABLE_CHECKING
4006 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4007 (vec, TREE_VEC_LENGTH (vec));
4009 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4011 t = make_node (NONTYPE_ARGUMENT_PACK);
4012 SET_ARGUMENT_PACK_ARGS (t, vec);
4013 TREE_TYPE (t) = type;
4019 /* This function returns TRUE if PARM_PACK is a template parameter
4020 pack and if ARG_PACK is what template_parm_to_arg returned when
4021 passed PARM_PACK. */
4024 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4026 /* For clarity in the comments below let's use the representation
4027 argument_pack<elements>' to denote an argument pack and its
4030 In the 'if' block below, we want to detect cases where
4031 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4032 check if ARG_PACK is an argument pack which sole element is
4033 the expansion of PARM_PACK. That argument pack is typically
4034 created by template_parm_to_arg when passed a parameter
4038 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4039 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4041 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4042 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4043 /* So we have an argument_pack<P...>. We want to test if P
4044 is actually PARM_PACK. We will not use cp_tree_equal to
4045 test P and PARM_PACK because during type fixup (by
4046 fixup_template_parm) P can be a pre-fixup version of a
4047 type and PARM_PACK be its post-fixup version.
4048 cp_tree_equal would consider them as different even
4049 though we would want to consider them compatible for our
4050 precise purpose here.
4052 Thus we are going to consider that P and PARM_PACK are
4053 compatible if they have the same DECL. */
4054 if ((/* If ARG_PACK is a type parameter pack named by the
4055 same DECL as parm_pack ... */
4057 && TYPE_P (parm_pack)
4058 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4059 /* ... or if PARM_PACK is a non-type parameter named by the
4060 same DECL as ARG_PACK. Note that PARM_PACK being a
4061 non-type parameter means it's either a PARM_DECL or a
4062 TEMPLATE_PARM_INDEX. */
4063 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4064 && ((TREE_CODE (parm_pack) == PARM_DECL
4065 && (TEMPLATE_PARM_DECL (pattern)
4066 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4067 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4068 && (TEMPLATE_PARM_DECL (pattern)
4069 == TEMPLATE_PARM_DECL (parm_pack))))))
4070 && template_parameter_pack_p (pattern))
4076 /* Within the declaration of a template, return all levels of template
4077 parameters that apply. The template parameters are represented as
4078 a TREE_VEC, in the form documented in cp-tree.h for template
4082 current_template_args (void)
4085 tree args = NULL_TREE;
4086 int length = TMPL_PARMS_DEPTH (current_template_parms);
4089 /* If there is only one level of template parameters, we do not
4090 create a TREE_VEC of TREE_VECs. Instead, we return a single
4091 TREE_VEC containing the arguments. */
4093 args = make_tree_vec (length);
4095 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4097 tree a = copy_node (TREE_VALUE (header));
4100 TREE_TYPE (a) = NULL_TREE;
4101 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4102 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4104 #ifdef ENABLE_CHECKING
4105 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4109 TREE_VEC_ELT (args, --l) = a;
4114 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4115 /* This can happen for template parms of a template template
4118 template<template<class T, class U> class TT> struct S;
4120 Consider the level of the parms of TT; T and U both have
4121 level 2; TT has no template parm of level 1. So in this case
4122 the first element of full_template_args is NULL_TREE. If we
4123 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4124 of 2. This will make tsubst wrongly consider that T and U
4125 have level 1. Instead, let's create a dummy vector as the
4126 first element of full_template_args so that TMPL_ARG_DEPTH
4127 returns the correct depth for args. */
4128 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4132 /* Update the declared TYPE by doing any lookups which were thought to be
4133 dependent, but are not now that we know the SCOPE of the declarator. */
4136 maybe_update_decl_type (tree orig_type, tree scope)
4138 tree type = orig_type;
4140 if (type == NULL_TREE)
4143 if (TREE_CODE (orig_type) == TYPE_DECL)
4144 type = TREE_TYPE (type);
4146 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4147 && dependent_type_p (type)
4148 /* Don't bother building up the args in this case. */
4149 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4151 /* tsubst in the args corresponding to the template parameters,
4152 including auto if present. Most things will be unchanged, but
4153 make_typename_type and tsubst_qualified_id will resolve
4154 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4155 tree args = current_template_args ();
4156 tree auto_node = type_uses_auto (type);
4160 tree auto_vec = make_tree_vec (1);
4161 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4162 args = add_to_template_args (args, auto_vec);
4164 pushed = push_scope (scope);
4165 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4170 if (type == error_mark_node)
4173 if (TREE_CODE (orig_type) == TYPE_DECL)
4175 if (same_type_p (type, TREE_TYPE (orig_type)))
4178 type = TYPE_NAME (type);
4183 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4184 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4185 a member template. Used by push_template_decl below. */
4188 build_template_decl (tree decl, tree parms, bool member_template_p)
4190 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4191 DECL_TEMPLATE_PARMS (tmpl) = parms;
4192 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4193 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4194 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4199 struct template_parm_data
4201 /* The level of the template parameters we are currently
4205 /* The index of the specialization argument we are currently
4209 /* An array whose size is the number of template parameters. The
4210 elements are nonzero if the parameter has been used in any one
4211 of the arguments processed so far. */
4214 /* An array whose size is the number of template arguments. The
4215 elements are nonzero if the argument makes use of template
4216 parameters of this level. */
4217 int* arg_uses_template_parms;
4220 /* Subroutine of push_template_decl used to see if each template
4221 parameter in a partial specialization is used in the explicit
4222 argument list. If T is of the LEVEL given in DATA (which is
4223 treated as a template_parm_data*), then DATA->PARMS is marked
4227 mark_template_parm (tree t, void* data)
4231 struct template_parm_data* tpd = (struct template_parm_data*) data;
4233 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4235 level = TEMPLATE_PARM_LEVEL (t);
4236 idx = TEMPLATE_PARM_IDX (t);
4240 level = TEMPLATE_TYPE_LEVEL (t);
4241 idx = TEMPLATE_TYPE_IDX (t);
4244 if (level == tpd->level)
4246 tpd->parms[idx] = 1;
4247 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4250 /* Return zero so that for_each_template_parm will continue the
4251 traversal of the tree; we want to mark *every* template parm. */
4255 /* Process the partial specialization DECL. */
4258 process_partial_specialization (tree decl)
4260 tree type = TREE_TYPE (decl);
4261 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4262 tree specargs = CLASSTYPE_TI_ARGS (type);
4263 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4264 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4267 int nargs = TREE_VEC_LENGTH (inner_args);
4270 bool did_error_intro = false;
4271 struct template_parm_data tpd;
4272 struct template_parm_data tpd2;
4274 gcc_assert (current_template_parms);
4276 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4277 ntparms = TREE_VEC_LENGTH (inner_parms);
4279 /* We check that each of the template parameters given in the
4280 partial specialization is used in the argument list to the
4281 specialization. For example:
4283 template <class T> struct S;
4284 template <class T> struct S<T*>;
4286 The second declaration is OK because `T*' uses the template
4287 parameter T, whereas
4289 template <class T> struct S<int>;
4291 is no good. Even trickier is:
4302 The S2<T> declaration is actually invalid; it is a
4303 full-specialization. Of course,
4306 struct S2<T (*)(U)>;
4308 or some such would have been OK. */
4309 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4310 tpd.parms = XALLOCAVEC (int, ntparms);
4311 memset (tpd.parms, 0, sizeof (int) * ntparms);
4313 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4314 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4315 for (i = 0; i < nargs; ++i)
4317 tpd.current_arg = i;
4318 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4319 &mark_template_parm,
4322 /*include_nondeduced_p=*/false);
4324 for (i = 0; i < ntparms; ++i)
4325 if (tpd.parms[i] == 0)
4327 /* One of the template parms was not used in the
4329 if (!did_error_intro)
4331 error ("template parameters not used in partial specialization:");
4332 did_error_intro = true;
4335 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4338 if (did_error_intro)
4339 return error_mark_node;
4341 /* [temp.class.spec]
4343 The argument list of the specialization shall not be identical to
4344 the implicit argument list of the primary template. */
4345 if (comp_template_args
4347 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4349 error ("partial specialization %qT does not specialize any template arguments", type);
4351 /* [temp.class.spec]
4353 A partially specialized non-type argument expression shall not
4354 involve template parameters of the partial specialization except
4355 when the argument expression is a simple identifier.
4357 The type of a template parameter corresponding to a specialized
4358 non-type argument shall not be dependent on a parameter of the
4361 Also, we verify that pack expansions only occur at the
4362 end of the argument list. */
4363 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4365 for (i = 0; i < nargs; ++i)
4367 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4368 tree arg = TREE_VEC_ELT (inner_args, i);
4369 tree packed_args = NULL_TREE;
4372 if (ARGUMENT_PACK_P (arg))
4374 /* Extract the arguments from the argument pack. We'll be
4375 iterating over these in the following loop. */
4376 packed_args = ARGUMENT_PACK_ARGS (arg);
4377 len = TREE_VEC_LENGTH (packed_args);
4380 for (j = 0; j < len; j++)
4383 /* Get the Jth argument in the parameter pack. */
4384 arg = TREE_VEC_ELT (packed_args, j);
4386 if (PACK_EXPANSION_P (arg))
4388 /* Pack expansions must come at the end of the
4390 if ((packed_args && j < len - 1)
4391 || (!packed_args && i < nargs - 1))
4393 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4394 error ("parameter pack argument %qE must be at the "
4395 "end of the template argument list", arg);
4397 error ("parameter pack argument %qT must be at the "
4398 "end of the template argument list", arg);
4402 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4403 /* We only care about the pattern. */
4404 arg = PACK_EXPANSION_PATTERN (arg);
4406 if (/* These first two lines are the `non-type' bit. */
4408 && TREE_CODE (arg) != TEMPLATE_DECL
4409 /* This next line is the `argument expression is not just a
4410 simple identifier' condition and also the `specialized
4411 non-type argument' bit. */
4412 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4414 if ((!packed_args && tpd.arg_uses_template_parms[i])
4415 || (packed_args && uses_template_parms (arg)))
4416 error ("template argument %qE involves template parameter(s)",
4420 /* Look at the corresponding template parameter,
4421 marking which template parameters its type depends
4423 tree type = TREE_TYPE (parm);
4427 /* We haven't yet initialized TPD2. Do so now. */
4428 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4429 /* The number of parameters here is the number in the
4430 main template, which, as checked in the assertion
4432 tpd2.parms = XALLOCAVEC (int, nargs);
4434 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4437 /* Mark the template parameters. But this time, we're
4438 looking for the template parameters of the main
4439 template, not in the specialization. */
4440 tpd2.current_arg = i;
4441 tpd2.arg_uses_template_parms[i] = 0;
4442 memset (tpd2.parms, 0, sizeof (int) * nargs);
4443 for_each_template_parm (type,
4444 &mark_template_parm,
4447 /*include_nondeduced_p=*/false);
4449 if (tpd2.arg_uses_template_parms [i])
4451 /* The type depended on some template parameters.
4452 If they are fully specialized in the
4453 specialization, that's OK. */
4456 for (j = 0; j < nargs; ++j)
4457 if (tpd2.parms[j] != 0
4458 && tpd.arg_uses_template_parms [j])
4461 error_n (input_location, count,
4462 "type %qT of template argument %qE depends "
4463 "on a template parameter",
4464 "type %qT of template argument %qE depends "
4465 "on template parameters",
4474 /* We should only get here once. */
4475 gcc_assert (!COMPLETE_TYPE_P (type));
4477 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4478 = tree_cons (specargs, inner_parms,
4479 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4480 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4482 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4483 inst = TREE_CHAIN (inst))
4485 tree inst_type = TREE_VALUE (inst);
4486 if (COMPLETE_TYPE_P (inst_type)
4487 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4489 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4490 if (spec && TREE_TYPE (spec) == type)
4491 permerror (input_location,
4492 "partial specialization of %qT after instantiation "
4493 "of %qT", type, inst_type);
4500 /* Check that a template declaration's use of default arguments and
4501 parameter packs is not invalid. Here, PARMS are the template
4502 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4503 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4507 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4508 declaration (but not a definition); 1 indicates a declaration, 2
4509 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4510 emitted for extraneous default arguments.
4512 Returns TRUE if there were no errors found, FALSE otherwise. */
4515 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4516 int is_partial, int is_friend_decl)
4519 int last_level_to_check;
4521 bool no_errors = true;
4525 A default template-argument shall not be specified in a
4526 function template declaration or a function template definition, nor
4527 in the template-parameter-list of the definition of a member of a
4530 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4531 /* You can't have a function template declaration in a local
4532 scope, nor you can you define a member of a class template in a
4536 if (current_class_type
4537 && !TYPE_BEING_DEFINED (current_class_type)
4538 && DECL_LANG_SPECIFIC (decl)
4539 && DECL_DECLARES_FUNCTION_P (decl)
4540 /* If this is either a friend defined in the scope of the class
4541 or a member function. */
4542 && (DECL_FUNCTION_MEMBER_P (decl)
4543 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4544 : DECL_FRIEND_CONTEXT (decl)
4545 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4547 /* And, if it was a member function, it really was defined in
4548 the scope of the class. */
4549 && (!DECL_FUNCTION_MEMBER_P (decl)
4550 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4551 /* We already checked these parameters when the template was
4552 declared, so there's no need to do it again now. This function
4553 was defined in class scope, but we're processing it's body now
4554 that the class is complete. */
4557 /* Core issue 226 (C++0x only): the following only applies to class
4559 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4563 If a template-parameter has a default template-argument, all
4564 subsequent template-parameters shall have a default
4565 template-argument supplied. */
4566 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4568 tree inner_parms = TREE_VALUE (parm_level);
4569 int ntparms = TREE_VEC_LENGTH (inner_parms);
4570 int seen_def_arg_p = 0;
4573 for (i = 0; i < ntparms; ++i)
4575 tree parm = TREE_VEC_ELT (inner_parms, i);
4577 if (parm == error_mark_node)
4580 if (TREE_PURPOSE (parm))
4582 else if (seen_def_arg_p
4583 && !template_parameter_pack_p (TREE_VALUE (parm)))
4585 error ("no default argument for %qD", TREE_VALUE (parm));
4586 /* For better subsequent error-recovery, we indicate that
4587 there should have been a default argument. */
4588 TREE_PURPOSE (parm) = error_mark_node;
4594 /* Don't complain about an enclosing partial
4596 && parm_level == parms
4597 && TREE_CODE (decl) == TYPE_DECL
4599 && template_parameter_pack_p (TREE_VALUE (parm)))
4601 /* A primary class template can only have one
4602 parameter pack, at the end of the template
4605 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4606 error ("parameter pack %qE must be at the end of the"
4607 " template parameter list", TREE_VALUE (parm));
4609 error ("parameter pack %qT must be at the end of the"
4610 " template parameter list",
4611 TREE_TYPE (TREE_VALUE (parm)));
4613 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4621 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4625 /* For an ordinary class template, default template arguments are
4626 allowed at the innermost level, e.g.:
4627 template <class T = int>
4629 but, in a partial specialization, they're not allowed even
4630 there, as we have in [temp.class.spec]:
4632 The template parameter list of a specialization shall not
4633 contain default template argument values.
4635 So, for a partial specialization, or for a function template
4636 (in C++98/C++03), we look at all of them. */
4639 /* But, for a primary class template that is not a partial
4640 specialization we look at all template parameters except the
4642 parms = TREE_CHAIN (parms);
4644 /* Figure out what error message to issue. */
4645 if (is_friend_decl == 2)
4646 msg = G_("default template arguments may not be used in function template "
4647 "friend re-declaration");
4648 else if (is_friend_decl)
4649 msg = G_("default template arguments may not be used in function template "
4650 "friend declarations");
4651 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4652 msg = G_("default template arguments may not be used in function templates "
4653 "without -std=c++0x or -std=gnu++0x");
4654 else if (is_partial)
4655 msg = G_("default template arguments may not be used in "
4656 "partial specializations");
4658 msg = G_("default argument for template parameter for class enclosing %qD");
4660 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4661 /* If we're inside a class definition, there's no need to
4662 examine the parameters to the class itself. On the one
4663 hand, they will be checked when the class is defined, and,
4664 on the other, default arguments are valid in things like:
4665 template <class T = double>
4666 struct S { template <class U> void f(U); };
4667 Here the default argument for `S' has no bearing on the
4668 declaration of `f'. */
4669 last_level_to_check = template_class_depth (current_class_type) + 1;
4671 /* Check everything. */
4672 last_level_to_check = 0;
4674 for (parm_level = parms;
4675 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4676 parm_level = TREE_CHAIN (parm_level))
4678 tree inner_parms = TREE_VALUE (parm_level);
4682 ntparms = TREE_VEC_LENGTH (inner_parms);
4683 for (i = 0; i < ntparms; ++i)
4685 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4688 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4693 if (is_friend_decl == 2)
4700 /* Clear out the default argument so that we are not
4702 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4706 /* At this point, if we're still interested in issuing messages,
4707 they must apply to classes surrounding the object declared. */
4709 msg = G_("default argument for template parameter for class "
4716 /* Worker for push_template_decl_real, called via
4717 for_each_template_parm. DATA is really an int, indicating the
4718 level of the parameters we are interested in. If T is a template
4719 parameter of that level, return nonzero. */
4722 template_parm_this_level_p (tree t, void* data)
4724 int this_level = *(int *)data;
4727 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4728 level = TEMPLATE_PARM_LEVEL (t);
4730 level = TEMPLATE_TYPE_LEVEL (t);
4731 return level == this_level;
4734 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4735 parameters given by current_template_args, or reuses a
4736 previously existing one, if appropriate. Returns the DECL, or an
4737 equivalent one, if it is replaced via a call to duplicate_decls.
4739 If IS_FRIEND is true, DECL is a friend declaration. */
4742 push_template_decl_real (tree decl, bool is_friend)
4750 int new_template_p = 0;
4751 /* True if the template is a member template, in the sense of
4753 bool member_template_p = false;
4755 if (decl == error_mark_node || !current_template_parms)
4756 return error_mark_node;
4758 /* See if this is a partial specialization. */
4759 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4760 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4761 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4763 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4767 /* For a friend, we want the context of the friend function, not
4768 the type of which it is a friend. */
4769 ctx = CP_DECL_CONTEXT (decl);
4770 else if (CP_DECL_CONTEXT (decl)
4771 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4772 /* In the case of a virtual function, we want the class in which
4774 ctx = CP_DECL_CONTEXT (decl);
4776 /* Otherwise, if we're currently defining some class, the DECL
4777 is assumed to be a member of the class. */
4778 ctx = current_scope ();
4780 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4783 if (!DECL_CONTEXT (decl))
4784 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4786 /* See if this is a primary template. */
4787 if (is_friend && ctx)
4788 /* A friend template that specifies a class context, i.e.
4789 template <typename T> friend void A<T>::f();
4793 primary = template_parm_scope_p ();
4797 if (DECL_CLASS_SCOPE_P (decl))
4798 member_template_p = true;
4799 if (TREE_CODE (decl) == TYPE_DECL
4800 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4802 error ("template class without a name");
4803 return error_mark_node;
4805 else if (TREE_CODE (decl) == FUNCTION_DECL)
4807 if (DECL_DESTRUCTOR_P (decl))
4811 A destructor shall not be a member template. */
4812 error ("destructor %qD declared as member template", decl);
4813 return error_mark_node;
4815 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4816 && (!prototype_p (TREE_TYPE (decl))
4817 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4818 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4819 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4820 == void_list_node)))
4822 /* [basic.stc.dynamic.allocation]
4824 An allocation function can be a function
4825 template. ... Template allocation functions shall
4826 have two or more parameters. */
4827 error ("invalid template declaration of %qD", decl);
4828 return error_mark_node;
4831 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4832 && CLASS_TYPE_P (TREE_TYPE (decl)))
4836 error ("template declaration of %q#D", decl);
4837 return error_mark_node;
4841 /* Check to see that the rules regarding the use of default
4842 arguments are not being violated. */
4843 check_default_tmpl_args (decl, current_template_parms,
4844 primary, is_partial, /*is_friend_decl=*/0);
4846 /* Ensure that there are no parameter packs in the type of this
4847 declaration that have not been expanded. */
4848 if (TREE_CODE (decl) == FUNCTION_DECL)
4850 /* Check each of the arguments individually to see if there are
4851 any bare parameter packs. */
4852 tree type = TREE_TYPE (decl);
4853 tree arg = DECL_ARGUMENTS (decl);
4854 tree argtype = TYPE_ARG_TYPES (type);
4856 while (arg && argtype)
4858 if (!FUNCTION_PARAMETER_PACK_P (arg)
4859 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4861 /* This is a PARM_DECL that contains unexpanded parameter
4862 packs. We have already complained about this in the
4863 check_for_bare_parameter_packs call, so just replace
4864 these types with ERROR_MARK_NODE. */
4865 TREE_TYPE (arg) = error_mark_node;
4866 TREE_VALUE (argtype) = error_mark_node;
4869 arg = DECL_CHAIN (arg);
4870 argtype = TREE_CHAIN (argtype);
4873 /* Check for bare parameter packs in the return type and the
4874 exception specifiers. */
4875 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4876 /* Errors were already issued, set return type to int
4877 as the frontend doesn't expect error_mark_node as
4879 TREE_TYPE (type) = integer_type_node;
4880 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4881 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4883 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4885 TREE_TYPE (decl) = error_mark_node;
4886 return error_mark_node;
4890 return process_partial_specialization (decl);
4892 args = current_template_args ();
4895 || TREE_CODE (ctx) == FUNCTION_DECL
4896 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4897 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4899 if (DECL_LANG_SPECIFIC (decl)
4900 && DECL_TEMPLATE_INFO (decl)
4901 && DECL_TI_TEMPLATE (decl))
4902 tmpl = DECL_TI_TEMPLATE (decl);
4903 /* If DECL is a TYPE_DECL for a class-template, then there won't
4904 be DECL_LANG_SPECIFIC. The information equivalent to
4905 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4906 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4907 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4908 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4910 /* Since a template declaration already existed for this
4911 class-type, we must be redeclaring it here. Make sure
4912 that the redeclaration is valid. */
4913 redeclare_class_template (TREE_TYPE (decl),
4914 current_template_parms);
4915 /* We don't need to create a new TEMPLATE_DECL; just use the
4916 one we already had. */
4917 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4921 tmpl = build_template_decl (decl, current_template_parms,
4925 if (DECL_LANG_SPECIFIC (decl)
4926 && DECL_TEMPLATE_SPECIALIZATION (decl))
4928 /* A specialization of a member template of a template
4930 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4931 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4932 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4938 tree a, t, current, parms;
4940 tree tinfo = get_template_info (decl);
4944 error ("template definition of non-template %q#D", decl);
4945 return error_mark_node;
4948 tmpl = TI_TEMPLATE (tinfo);
4950 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4951 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4952 && DECL_TEMPLATE_SPECIALIZATION (decl)
4953 && DECL_MEMBER_TEMPLATE_P (tmpl))
4957 /* The declaration is a specialization of a member
4958 template, declared outside the class. Therefore, the
4959 innermost template arguments will be NULL, so we
4960 replace them with the arguments determined by the
4961 earlier call to check_explicit_specialization. */
4962 args = DECL_TI_ARGS (decl);
4965 = build_template_decl (decl, current_template_parms,
4967 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4968 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4969 DECL_TI_TEMPLATE (decl) = new_tmpl;
4970 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4971 DECL_TEMPLATE_INFO (new_tmpl)
4972 = build_template_info (tmpl, args);
4974 register_specialization (new_tmpl,
4975 most_general_template (tmpl),
4981 /* Make sure the template headers we got make sense. */
4983 parms = DECL_TEMPLATE_PARMS (tmpl);
4984 i = TMPL_PARMS_DEPTH (parms);
4985 if (TMPL_ARGS_DEPTH (args) != i)
4987 error ("expected %d levels of template parms for %q#D, got %d",
4988 i, decl, TMPL_ARGS_DEPTH (args));
4991 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4993 a = TMPL_ARGS_LEVEL (args, i);
4994 t = INNERMOST_TEMPLATE_PARMS (parms);
4996 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4998 if (current == decl)
4999 error ("got %d template parameters for %q#D",
5000 TREE_VEC_LENGTH (a), decl);
5002 error ("got %d template parameters for %q#T",
5003 TREE_VEC_LENGTH (a), current);
5004 error (" but %d required", TREE_VEC_LENGTH (t));
5005 return error_mark_node;
5008 if (current == decl)
5010 else if (current == NULL_TREE)
5011 /* Can happen in erroneous input. */
5014 current = (TYPE_P (current)
5015 ? TYPE_CONTEXT (current)
5016 : DECL_CONTEXT (current));
5019 /* Check that the parms are used in the appropriate qualifying scopes
5020 in the declarator. */
5021 if (!comp_template_args
5023 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5026 template arguments to %qD do not match original template %qD",
5027 decl, DECL_TEMPLATE_RESULT (tmpl));
5028 if (!uses_template_parms (TI_ARGS (tinfo)))
5029 inform (input_location, "use template<> for an explicit specialization");
5030 /* Avoid crash in import_export_decl. */
5031 DECL_INTERFACE_KNOWN (decl) = 1;
5032 return error_mark_node;
5036 DECL_TEMPLATE_RESULT (tmpl) = decl;
5037 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5039 /* Push template declarations for global functions and types. Note
5040 that we do not try to push a global template friend declared in a
5041 template class; such a thing may well depend on the template
5042 parameters of the class. */
5043 if (new_template_p && !ctx
5044 && !(is_friend && template_class_depth (current_class_type) > 0))
5046 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5047 if (tmpl == error_mark_node)
5048 return error_mark_node;
5050 /* Hide template friend classes that haven't been declared yet. */
5051 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5053 DECL_ANTICIPATED (tmpl) = 1;
5054 DECL_FRIEND_P (tmpl) = 1;
5060 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5063 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5064 if (DECL_CONV_FN_P (tmpl))
5066 int depth = TMPL_PARMS_DEPTH (parms);
5068 /* It is a conversion operator. See if the type converted to
5069 depends on innermost template operands. */
5071 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5073 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5076 /* Give template template parms a DECL_CONTEXT of the template
5077 for which they are a parameter. */
5078 parms = INNERMOST_TEMPLATE_PARMS (parms);
5079 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5081 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5082 if (TREE_CODE (parm) == TEMPLATE_DECL)
5083 DECL_CONTEXT (parm) = tmpl;
5087 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5088 back to its most general template. If TMPL is a specialization,
5089 ARGS may only have the innermost set of arguments. Add the missing
5090 argument levels if necessary. */
5091 if (DECL_TEMPLATE_INFO (tmpl))
5092 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5094 info = build_template_info (tmpl, args);
5096 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5097 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5098 else if (DECL_LANG_SPECIFIC (decl))
5099 DECL_TEMPLATE_INFO (decl) = info;
5101 return DECL_TEMPLATE_RESULT (tmpl);
5105 push_template_decl (tree decl)
5107 return push_template_decl_real (decl, false);
5110 /* Called when a class template TYPE is redeclared with the indicated
5111 template PARMS, e.g.:
5113 template <class T> struct S;
5114 template <class T> struct S {}; */
5117 redeclare_class_template (tree type, tree parms)
5123 if (!TYPE_TEMPLATE_INFO (type))
5125 error ("%qT is not a template type", type);
5129 tmpl = TYPE_TI_TEMPLATE (type);
5130 if (!PRIMARY_TEMPLATE_P (tmpl))
5131 /* The type is nested in some template class. Nothing to worry
5132 about here; there are no new template parameters for the nested
5138 error ("template specifiers not specified in declaration of %qD",
5143 parms = INNERMOST_TEMPLATE_PARMS (parms);
5144 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5146 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5148 error_n (input_location, TREE_VEC_LENGTH (parms),
5149 "redeclared with %d template parameter",
5150 "redeclared with %d template parameters",
5151 TREE_VEC_LENGTH (parms));
5152 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5153 "previous declaration %q+D used %d template parameter",
5154 "previous declaration %q+D used %d template parameters",
5155 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5159 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5166 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5167 || TREE_VEC_ELT (parms, i) == error_mark_node)
5170 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5171 if (tmpl_parm == error_mark_node)
5174 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5175 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5176 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5178 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5180 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5181 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5182 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5183 || (TREE_CODE (tmpl_parm) != PARM_DECL
5184 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5185 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5186 || (TREE_CODE (tmpl_parm) == PARM_DECL
5187 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5188 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5190 error ("template parameter %q+#D", tmpl_parm);
5191 error ("redeclared here as %q#D", parm);
5195 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5197 /* We have in [temp.param]:
5199 A template-parameter may not be given default arguments
5200 by two different declarations in the same scope. */
5201 error_at (input_location, "redefinition of default argument for %q#D", parm);
5202 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5203 "original definition appeared here");
5207 if (parm_default != NULL_TREE)
5208 /* Update the previous template parameters (which are the ones
5209 that will really count) with the new default value. */
5210 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5211 else if (tmpl_default != NULL_TREE)
5212 /* Update the new parameters, too; they'll be used as the
5213 parameters for any members. */
5214 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5220 /* Simplify EXPR if it is a non-dependent expression. Returns the
5221 (possibly simplified) expression. */
5224 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5226 if (expr == NULL_TREE)
5229 /* If we're in a template, but EXPR isn't value dependent, simplify
5230 it. We're supposed to treat:
5232 template <typename T> void f(T[1 + 1]);
5233 template <typename T> void f(T[2]);
5235 as two declarations of the same function, for example. */
5236 if (processing_template_decl
5237 && !type_dependent_expression_p (expr)
5238 && potential_constant_expression (expr)
5239 && !value_dependent_expression_p (expr))
5241 HOST_WIDE_INT saved_processing_template_decl;
5243 saved_processing_template_decl = processing_template_decl;
5244 processing_template_decl = 0;
5245 expr = tsubst_copy_and_build (expr,
5248 /*in_decl=*/NULL_TREE,
5249 /*function_p=*/false,
5250 /*integral_constant_expression_p=*/true);
5251 processing_template_decl = saved_processing_template_decl;
5257 fold_non_dependent_expr (tree expr)
5259 return fold_non_dependent_expr_sfinae (expr, tf_error);
5262 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5263 must be a function or a pointer-to-function type, as specified
5264 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5265 and check that the resulting function has external linkage. */
5268 convert_nontype_argument_function (tree type, tree expr)
5273 fn = instantiate_type (type, fns, tf_none);
5274 if (fn == error_mark_node)
5275 return error_mark_node;
5278 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5279 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5280 if (BASELINK_P (fn_no_ptr))
5281 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5283 /* [temp.arg.nontype]/1
5285 A template-argument for a non-type, non-template template-parameter
5288 -- the address of an object or function with external linkage. */
5289 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
5291 error ("%qE is not a valid template argument for type %qT "
5292 "because function %qD has not external linkage",
5293 expr, type, fn_no_ptr);
5300 /* Subroutine of convert_nontype_argument.
5301 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5302 Emit an error otherwise. */
5305 check_valid_ptrmem_cst_expr (tree type, tree expr,
5306 tsubst_flags_t complain)
5309 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5311 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5313 if (complain & tf_error)
5315 error ("%qE is not a valid template argument for type %qT",
5317 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5322 /* Returns TRUE iff the address of OP is value-dependent.
5324 14.6.2.4 [temp.dep.temp]:
5325 A non-integral non-type template-argument is dependent if its type is
5326 dependent or it has either of the following forms
5329 and contains a nested-name-specifier which specifies a class-name that
5330 names a dependent type.
5332 We generalize this to just say that the address of a member of a
5333 dependent class is value-dependent; the above doesn't cover the
5334 address of a static data member named with an unqualified-id. */
5337 has_value_dependent_address (tree op)
5339 /* We could use get_inner_reference here, but there's no need;
5340 this is only relevant for template non-type arguments, which
5341 can only be expressed as &id-expression. */
5344 tree ctx = CP_DECL_CONTEXT (op);
5345 if (TYPE_P (ctx) && dependent_type_p (ctx))
5352 /* The next set of functions are used for providing helpful explanatory
5353 diagnostics for failed overload resolution. Their messages should be
5354 indented by two spaces for consistency with the messages in
5358 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5364 unify_parameter_deduction_failure (bool explain_p, tree parm)
5367 inform (input_location,
5368 " couldn't deduce template parameter %qD", parm);
5373 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5379 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5382 inform (input_location,
5383 " types %qT and %qT have incompatible cv-qualifiers",
5389 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5392 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5397 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5400 inform (input_location,
5401 " template parameter %qD is not a parameter pack, but "
5408 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5411 inform (input_location,
5412 " template argument %qE does not match "
5413 "pointer-to-member constant %qE",
5419 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5422 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5427 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5430 inform (input_location,
5431 " inconsistent parameter pack deduction with %qT and %qT",
5437 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5440 inform (input_location,
5441 " deduced conflicting types for parameter %qT (%qT and %qT)",
5442 parm, first, second);
5447 unify_vla_arg (bool explain_p, tree arg)
5450 inform (input_location,
5451 " variable-sized array type %qT is not "
5452 "a valid template argument",
5458 unify_method_type_error (bool explain_p, tree arg)
5461 inform (input_location,
5462 " member function type %qT is not a valid template argument",
5468 unify_arity (bool explain_p, int have, int wanted)
5471 inform_n (input_location, wanted,
5472 " candidate expects %d argument, %d provided",
5473 " candidate expects %d arguments, %d provided",
5479 unify_too_many_arguments (bool explain_p, int have, int wanted)
5481 return unify_arity (explain_p, have, wanted);
5485 unify_too_few_arguments (bool explain_p, int have, int wanted)
5487 return unify_arity (explain_p, have, wanted);
5491 unify_arg_conversion (bool explain_p, tree to_type,
5492 tree from_type, tree arg)
5495 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5496 arg, from_type, to_type);
5501 unify_no_common_base (bool explain_p, enum template_base_result r,
5502 tree parm, tree arg)
5507 case tbr_ambiguous_baseclass:
5508 inform (input_location, " %qT is an ambiguous base class of %qT",
5512 inform (input_location, " %qT is not derived from %qT", arg, parm);
5519 unify_inconsistent_template_template_parameters (bool explain_p)
5522 inform (input_location,
5523 " template parameters of a template template argument are "
5524 "inconsistent with other deduced template arguments");
5529 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5532 inform (input_location,
5533 " can't deduce a template for %qT from non-template type %qT",
5539 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5542 inform (input_location,
5543 " template argument %qE does not match %qD", arg, parm);
5548 unify_overload_resolution_failure (bool explain_p, tree arg)
5551 inform (input_location,
5552 " could not resolve address from overloaded function %qE",
5557 /* Attempt to convert the non-type template parameter EXPR to the
5558 indicated TYPE. If the conversion is successful, return the
5559 converted value. If the conversion is unsuccessful, return
5560 NULL_TREE if we issued an error message, or error_mark_node if we
5561 did not. We issue error messages for out-and-out bad template
5562 parameters, but not simply because the conversion failed, since we
5563 might be just trying to do argument deduction. Both TYPE and EXPR
5564 must be non-dependent.
5566 The conversion follows the special rules described in
5567 [temp.arg.nontype], and it is much more strict than an implicit
5570 This function is called twice for each template argument (see
5571 lookup_template_class for a more accurate description of this
5572 problem). This means that we need to handle expressions which
5573 are not valid in a C++ source, but can be created from the
5574 first call (for instance, casts to perform conversions). These
5575 hacks can go away after we fix the double coercion problem. */
5578 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5582 /* Detect immediately string literals as invalid non-type argument.
5583 This special-case is not needed for correctness (we would easily
5584 catch this later), but only to provide better diagnostic for this
5585 common user mistake. As suggested by DR 100, we do not mention
5586 linkage issues in the diagnostic as this is not the point. */
5587 /* FIXME we're making this OK. */
5588 if (TREE_CODE (expr) == STRING_CST)
5590 if (complain & tf_error)
5591 error ("%qE is not a valid template argument for type %qT "
5592 "because string literals can never be used in this context",
5597 /* Add the ADDR_EXPR now for the benefit of
5598 value_dependent_expression_p. */
5599 if (TYPE_PTROBV_P (type)
5600 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5601 expr = decay_conversion (expr);
5603 /* If we are in a template, EXPR may be non-dependent, but still
5604 have a syntactic, rather than semantic, form. For example, EXPR
5605 might be a SCOPE_REF, rather than the VAR_DECL to which the
5606 SCOPE_REF refers. Preserving the qualifying scope is necessary
5607 so that access checking can be performed when the template is
5608 instantiated -- but here we need the resolved form so that we can
5609 convert the argument. */
5610 if (TYPE_REF_OBJ_P (type)
5611 && has_value_dependent_address (expr))
5612 /* If we want the address and it's value-dependent, don't fold. */;
5613 else if (!type_unknown_p (expr))
5614 expr = fold_non_dependent_expr_sfinae (expr, complain);
5615 if (error_operand_p (expr))
5616 return error_mark_node;
5617 expr_type = TREE_TYPE (expr);
5618 if (TREE_CODE (type) == REFERENCE_TYPE)
5619 expr = mark_lvalue_use (expr);
5621 expr = mark_rvalue_use (expr);
5623 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5624 to a non-type argument of "nullptr". */
5625 if (expr == nullptr_node
5626 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5627 expr = convert (type, expr);
5629 /* In C++11, non-type template arguments can be arbitrary constant
5630 expressions. But don't fold a PTRMEM_CST to a CONSTRUCTOR yet. */
5631 if (cxx_dialect >= cxx0x && TREE_CODE (expr) != PTRMEM_CST)
5632 expr = maybe_constant_value (expr);
5634 /* HACK: Due to double coercion, we can get a
5635 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5636 which is the tree that we built on the first call (see
5637 below when coercing to reference to object or to reference to
5638 function). We just strip everything and get to the arg.
5639 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5641 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5643 tree probe_type, probe = expr;
5644 if (REFERENCE_REF_P (probe))
5645 probe = TREE_OPERAND (probe, 0);
5646 probe_type = TREE_TYPE (probe);
5647 if (TREE_CODE (probe) == NOP_EXPR)
5649 /* ??? Maybe we could use convert_from_reference here, but we
5650 would need to relax its constraints because the NOP_EXPR
5651 could actually change the type to something more cv-qualified,
5652 and this is not folded by convert_from_reference. */
5653 tree addr = TREE_OPERAND (probe, 0);
5654 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5655 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5656 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5657 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5658 (TREE_TYPE (probe_type),
5659 TREE_TYPE (TREE_TYPE (addr))));
5661 expr = TREE_OPERAND (addr, 0);
5662 expr_type = TREE_TYPE (expr);
5666 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5667 parameter is a pointer to object, through decay and
5668 qualification conversion. Let's strip everything. */
5669 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5672 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5673 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5674 /* Skip the ADDR_EXPR only if it is part of the decay for
5675 an array. Otherwise, it is part of the original argument
5676 in the source code. */
5677 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5678 expr = TREE_OPERAND (expr, 0);
5679 expr_type = TREE_TYPE (expr);
5682 /* [temp.arg.nontype]/5, bullet 1
5684 For a non-type template-parameter of integral or enumeration type,
5685 integral promotions (_conv.prom_) and integral conversions
5686 (_conv.integral_) are applied. */
5687 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5689 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5690 t = maybe_constant_value (t);
5691 if (t != error_mark_node)
5694 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5695 return error_mark_node;
5697 /* Notice that there are constant expressions like '4 % 0' which
5698 do not fold into integer constants. */
5699 if (TREE_CODE (expr) != INTEGER_CST)
5701 if (complain & tf_error)
5703 int errs = errorcount, warns = warningcount;
5704 expr = cxx_constant_value (expr);
5705 if (errorcount > errs || warningcount > warns)
5706 inform (EXPR_LOC_OR_HERE (expr),
5707 "in template argument for type %qT ", type);
5708 if (expr == error_mark_node)
5710 /* else cxx_constant_value complained but gave us
5711 a real constant, so go ahead. */
5712 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5718 /* [temp.arg.nontype]/5, bullet 2
5720 For a non-type template-parameter of type pointer to object,
5721 qualification conversions (_conv.qual_) and the array-to-pointer
5722 conversion (_conv.array_) are applied. */
5723 else if (TYPE_PTROBV_P (type))
5725 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5727 A template-argument for a non-type, non-template template-parameter
5728 shall be one of: [...]
5730 -- the name of a non-type template-parameter;
5731 -- the address of an object or function with external linkage, [...]
5732 expressed as "& id-expression" where the & is optional if the name
5733 refers to a function or array, or if the corresponding
5734 template-parameter is a reference.
5736 Here, we do not care about functions, as they are invalid anyway
5737 for a parameter of type pointer-to-object. */
5739 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5740 /* Non-type template parameters are OK. */
5742 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5743 /* Null pointer values are OK in C++11. */;
5744 else if (TREE_CODE (expr) != ADDR_EXPR
5745 && TREE_CODE (expr_type) != ARRAY_TYPE)
5747 if (TREE_CODE (expr) == VAR_DECL)
5749 error ("%qD is not a valid template argument "
5750 "because %qD is a variable, not the address of "
5755 /* Other values, like integer constants, might be valid
5756 non-type arguments of some other type. */
5757 return error_mark_node;
5763 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5764 ? TREE_OPERAND (expr, 0) : expr);
5765 if (TREE_CODE (decl) != VAR_DECL)
5767 error ("%qE is not a valid template argument of type %qT "
5768 "because %qE is not a variable",
5772 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5774 error ("%qE is not a valid template argument of type %qT "
5775 "because %qD does not have external linkage",
5781 expr = decay_conversion (expr);
5782 if (expr == error_mark_node)
5783 return error_mark_node;
5785 expr = perform_qualification_conversions (type, expr);
5786 if (expr == error_mark_node)
5787 return error_mark_node;
5789 /* [temp.arg.nontype]/5, bullet 3
5791 For a non-type template-parameter of type reference to object, no
5792 conversions apply. The type referred to by the reference may be more
5793 cv-qualified than the (otherwise identical) type of the
5794 template-argument. The template-parameter is bound directly to the
5795 template-argument, which must be an lvalue. */
5796 else if (TYPE_REF_OBJ_P (type))
5798 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5800 return error_mark_node;
5802 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5804 error ("%qE is not a valid template argument for type %qT "
5805 "because of conflicts in cv-qualification", expr, type);
5809 if (!real_lvalue_p (expr))
5811 error ("%qE is not a valid template argument for type %qT "
5812 "because it is not an lvalue", expr, type);
5816 /* [temp.arg.nontype]/1
5818 A template-argument for a non-type, non-template template-parameter
5819 shall be one of: [...]
5821 -- the address of an object or function with external linkage. */
5822 if (TREE_CODE (expr) == INDIRECT_REF
5823 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5825 expr = TREE_OPERAND (expr, 0);
5828 error ("%q#D is not a valid template argument for type %qT "
5829 "because a reference variable does not have a constant "
5830 "address", expr, type);
5837 error ("%qE is not a valid template argument for type %qT "
5838 "because it is not an object with external linkage",
5843 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5845 error ("%qE is not a valid template argument for type %qT "
5846 "because object %qD has not external linkage",
5851 expr = build_nop (type, build_address (expr));
5853 /* [temp.arg.nontype]/5, bullet 4
5855 For a non-type template-parameter of type pointer to function, only
5856 the function-to-pointer conversion (_conv.func_) is applied. If the
5857 template-argument represents a set of overloaded functions (or a
5858 pointer to such), the matching function is selected from the set
5860 else if (TYPE_PTRFN_P (type))
5862 /* If the argument is a template-id, we might not have enough
5863 context information to decay the pointer. */
5864 if (!type_unknown_p (expr_type))
5866 expr = decay_conversion (expr);
5867 if (expr == error_mark_node)
5868 return error_mark_node;
5871 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5872 /* Null pointer values are OK in C++11. */
5873 return perform_qualification_conversions (type, expr);
5875 expr = convert_nontype_argument_function (type, expr);
5876 if (!expr || expr == error_mark_node)
5879 if (TREE_CODE (expr) != ADDR_EXPR)
5881 error ("%qE is not a valid template argument for type %qT", expr, type);
5882 error ("it must be the address of a function with external linkage");
5886 /* [temp.arg.nontype]/5, bullet 5
5888 For a non-type template-parameter of type reference to function, no
5889 conversions apply. If the template-argument represents a set of
5890 overloaded functions, the matching function is selected from the set
5892 else if (TYPE_REFFN_P (type))
5894 if (TREE_CODE (expr) == ADDR_EXPR)
5896 error ("%qE is not a valid template argument for type %qT "
5897 "because it is a pointer", expr, type);
5898 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5902 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5903 if (!expr || expr == error_mark_node)
5906 expr = build_nop (type, build_address (expr));
5908 /* [temp.arg.nontype]/5, bullet 6
5910 For a non-type template-parameter of type pointer to member function,
5911 no conversions apply. If the template-argument represents a set of
5912 overloaded member functions, the matching member function is selected
5913 from the set (_over.over_). */
5914 else if (TYPE_PTRMEMFUNC_P (type))
5916 expr = instantiate_type (type, expr, tf_none);
5917 if (expr == error_mark_node)
5918 return error_mark_node;
5920 /* [temp.arg.nontype] bullet 1 says the pointer to member
5921 expression must be a pointer-to-member constant. */
5922 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5923 return error_mark_node;
5925 /* There is no way to disable standard conversions in
5926 resolve_address_of_overloaded_function (called by
5927 instantiate_type). It is possible that the call succeeded by
5928 converting &B::I to &D::I (where B is a base of D), so we need
5929 to reject this conversion here.
5931 Actually, even if there was a way to disable standard conversions,
5932 it would still be better to reject them here so that we can
5933 provide a superior diagnostic. */
5934 if (!same_type_p (TREE_TYPE (expr), type))
5936 error ("%qE is not a valid template argument for type %qT "
5937 "because it is of type %qT", expr, type,
5939 /* If we are just one standard conversion off, explain. */
5940 if (can_convert (type, TREE_TYPE (expr)))
5941 inform (input_location,
5942 "standard conversions are not allowed in this context");
5946 /* [temp.arg.nontype]/5, bullet 7
5948 For a non-type template-parameter of type pointer to data member,
5949 qualification conversions (_conv.qual_) are applied. */
5950 else if (TYPE_PTRMEM_P (type))
5952 /* [temp.arg.nontype] bullet 1 says the pointer to member
5953 expression must be a pointer-to-member constant. */
5954 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5955 return error_mark_node;
5957 expr = perform_qualification_conversions (type, expr);
5958 if (expr == error_mark_node)
5961 else if (NULLPTR_TYPE_P (type))
5963 if (expr != nullptr_node)
5965 error ("%qE is not a valid template argument for type %qT "
5966 "because it is of type %qT", expr, type, TREE_TYPE (expr));
5971 /* A template non-type parameter must be one of the above. */
5975 /* Sanity check: did we actually convert the argument to the
5977 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5978 (type, TREE_TYPE (expr)));
5982 /* Subroutine of coerce_template_template_parms, which returns 1 if
5983 PARM_PARM and ARG_PARM match using the rule for the template
5984 parameters of template template parameters. Both PARM and ARG are
5985 template parameters; the rest of the arguments are the same as for
5986 coerce_template_template_parms.
5989 coerce_template_template_parm (tree parm,
5991 tsubst_flags_t complain,
5995 if (arg == NULL_TREE || arg == error_mark_node
5996 || parm == NULL_TREE || parm == error_mark_node)
5999 if (TREE_CODE (arg) != TREE_CODE (parm))
6002 switch (TREE_CODE (parm))
6005 /* We encounter instantiations of templates like
6006 template <template <template <class> class> class TT>
6009 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6010 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6012 if (!coerce_template_template_parms
6013 (parmparm, argparm, complain, in_decl, outer_args))
6019 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6020 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6021 /* Argument is a parameter pack but parameter is not. */
6026 /* The tsubst call is used to handle cases such as
6028 template <int> class C {};
6029 template <class T, template <T> class TT> class D {};
6032 i.e. the parameter list of TT depends on earlier parameters. */
6033 if (!uses_template_parms (TREE_TYPE (arg))
6035 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6039 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6040 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6041 /* Argument is a parameter pack but parameter is not. */
6054 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6055 template template parameters. Both PARM_PARMS and ARG_PARMS are
6056 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6059 Consider the example:
6060 template <class T> class A;
6061 template<template <class U> class TT> class B;
6063 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6064 the parameters to A, and OUTER_ARGS contains A. */
6067 coerce_template_template_parms (tree parm_parms,
6069 tsubst_flags_t complain,
6073 int nparms, nargs, i;
6077 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6078 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6080 nparms = TREE_VEC_LENGTH (parm_parms);
6081 nargs = TREE_VEC_LENGTH (arg_parms);
6083 /* Determine whether we have a parameter pack at the end of the
6084 template template parameter's template parameter list. */
6085 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6087 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6089 if (parm == error_mark_node)
6092 switch (TREE_CODE (parm))
6096 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6101 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6111 && !(variadic_p && nargs >= nparms - 1))
6114 /* Check all of the template parameters except the parameter pack at
6115 the end (if any). */
6116 for (i = 0; i < nparms - variadic_p; ++i)
6118 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6119 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6122 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6123 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6125 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6133 /* Check each of the template parameters in the template
6134 argument against the template parameter pack at the end of
6135 the template template parameter. */
6136 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6139 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6141 for (; i < nargs; ++i)
6143 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6146 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6148 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6157 /* Verifies that the deduced template arguments (in TARGS) for the
6158 template template parameters (in TPARMS) represent valid bindings,
6159 by comparing the template parameter list of each template argument
6160 to the template parameter list of its corresponding template
6161 template parameter, in accordance with DR150. This
6162 routine can only be called after all template arguments have been
6163 deduced. It will return TRUE if all of the template template
6164 parameter bindings are okay, FALSE otherwise. */
6166 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6168 int i, ntparms = TREE_VEC_LENGTH (tparms);
6171 /* We're dealing with template parms in this process. */
6172 ++processing_template_decl;
6174 targs = INNERMOST_TEMPLATE_ARGS (targs);
6176 for (i = 0; i < ntparms; ++i)
6178 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6179 tree targ = TREE_VEC_ELT (targs, i);
6181 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6183 tree packed_args = NULL_TREE;
6186 if (ARGUMENT_PACK_P (targ))
6188 /* Look inside the argument pack. */
6189 packed_args = ARGUMENT_PACK_ARGS (targ);
6190 len = TREE_VEC_LENGTH (packed_args);
6193 for (idx = 0; idx < len; ++idx)
6195 tree targ_parms = NULL_TREE;
6198 /* Extract the next argument from the argument
6200 targ = TREE_VEC_ELT (packed_args, idx);
6202 if (PACK_EXPANSION_P (targ))
6203 /* Look at the pattern of the pack expansion. */
6204 targ = PACK_EXPANSION_PATTERN (targ);
6206 /* Extract the template parameters from the template
6208 if (TREE_CODE (targ) == TEMPLATE_DECL)
6209 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6210 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6211 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6213 /* Verify that we can coerce the template template
6214 parameters from the template argument to the template
6215 parameter. This requires an exact match. */
6217 && !coerce_template_template_parms
6218 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6233 --processing_template_decl;
6237 /* Since type attributes aren't mangled, we need to strip them from
6238 template type arguments. */
6241 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6244 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6246 mv = TYPE_MAIN_VARIANT (arg);
6247 arg = strip_typedefs (arg);
6248 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6249 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6251 if (complain & tf_warning)
6252 warning (0, "ignoring attributes on template argument %qT", arg);
6253 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6254 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6259 /* Convert the indicated template ARG as necessary to match the
6260 indicated template PARM. Returns the converted ARG, or
6261 error_mark_node if the conversion was unsuccessful. Error and
6262 warning messages are issued under control of COMPLAIN. This
6263 conversion is for the Ith parameter in the parameter list. ARGS is
6264 the full set of template arguments deduced so far. */
6267 convert_template_argument (tree parm,
6270 tsubst_flags_t complain,
6276 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6278 if (TREE_CODE (arg) == TREE_LIST
6279 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6281 /* The template argument was the name of some
6282 member function. That's usually
6283 invalid, but static members are OK. In any
6284 case, grab the underlying fields/functions
6285 and issue an error later if required. */
6286 orig_arg = TREE_VALUE (arg);
6287 TREE_TYPE (arg) = unknown_type_node;
6292 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6293 requires_type = (TREE_CODE (parm) == TYPE_DECL
6294 || requires_tmpl_type);
6296 /* When determining whether an argument pack expansion is a template,
6297 look at the pattern. */
6298 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6299 arg = PACK_EXPANSION_PATTERN (arg);
6301 /* Deal with an injected-class-name used as a template template arg. */
6302 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6304 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6305 if (TREE_CODE (t) == TEMPLATE_DECL)
6307 if (cxx_dialect >= cxx0x)
6308 /* OK under DR 1004. */;
6309 else if (complain & tf_warning_or_error)
6310 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6311 " used as template template argument", TYPE_NAME (arg));
6312 else if (flag_pedantic_errors)
6320 ((TREE_CODE (arg) == TEMPLATE_DECL
6321 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6322 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6323 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6326 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6327 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6328 arg = TYPE_STUB_DECL (arg);
6330 is_type = TYPE_P (arg) || is_tmpl_type;
6332 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6333 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6335 permerror (input_location, "to refer to a type member of a template parameter, "
6336 "use %<typename %E%>", orig_arg);
6338 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6339 TREE_OPERAND (arg, 1),
6341 complain & tf_error);
6345 if (is_type != requires_type)
6349 if (complain & tf_error)
6351 error ("type/value mismatch at argument %d in template "
6352 "parameter list for %qD",
6355 error (" expected a constant of type %qT, got %qT",
6357 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6358 else if (requires_tmpl_type)
6359 error (" expected a class template, got %qE", orig_arg);
6361 error (" expected a type, got %qE", orig_arg);
6364 return error_mark_node;
6366 if (is_tmpl_type ^ requires_tmpl_type)
6368 if (in_decl && (complain & tf_error))
6370 error ("type/value mismatch at argument %d in template "
6371 "parameter list for %qD",
6374 error (" expected a type, got %qT", DECL_NAME (arg));
6376 error (" expected a class template, got %qT", orig_arg);
6378 return error_mark_node;
6383 if (requires_tmpl_type)
6385 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6386 /* The number of argument required is not known yet.
6387 Just accept it for now. */
6388 val = TREE_TYPE (arg);
6391 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6394 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6396 if (coerce_template_template_parms (parmparm, argparm,
6402 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6404 if (val != error_mark_node)
6406 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6407 val = TREE_TYPE (val);
6408 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6409 val = make_pack_expansion (val);
6414 if (in_decl && (complain & tf_error))
6416 error ("type/value mismatch at argument %d in "
6417 "template parameter list for %qD",
6419 error (" expected a template of type %qD, got %qT",
6423 val = error_mark_node;
6429 /* We only form one instance of each template specialization.
6430 Therefore, if we use a non-canonical variant (i.e., a
6431 typedef), any future messages referring to the type will use
6432 the typedef, which is confusing if those future uses do not
6433 themselves also use the typedef. */
6435 val = canonicalize_type_argument (val, complain);
6439 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6441 if (invalid_nontype_parm_type_p (t, complain))
6442 return error_mark_node;
6444 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6446 if (same_type_p (t, TREE_TYPE (orig_arg)))
6450 /* Not sure if this is reachable, but it doesn't hurt
6452 error ("type mismatch in nontype parameter pack");
6453 val = error_mark_node;
6456 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6457 /* We used to call digest_init here. However, digest_init
6458 will report errors, which we don't want when complain
6459 is zero. More importantly, digest_init will try too
6460 hard to convert things: for example, `0' should not be
6461 converted to pointer type at this point according to
6462 the standard. Accepting this is not merely an
6463 extension, since deciding whether or not these
6464 conversions can occur is part of determining which
6465 function template to call, or whether a given explicit
6466 argument specification is valid. */
6467 val = convert_nontype_argument (t, orig_arg, complain);
6471 if (val == NULL_TREE)
6472 val = error_mark_node;
6473 else if (val == error_mark_node && (complain & tf_error))
6474 error ("could not convert template argument %qE to %qT", orig_arg, t);
6476 if (TREE_CODE (val) == SCOPE_REF)
6478 /* Strip typedefs from the SCOPE_REF. */
6479 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6480 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6482 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6483 QUALIFIED_NAME_IS_TEMPLATE (val));
6490 /* Coerces the remaining template arguments in INNER_ARGS (from
6491 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6492 Returns the coerced argument pack. PARM_IDX is the position of this
6493 parameter in the template parameter list. ARGS is the original
6494 template argument list. */
6496 coerce_template_parameter_pack (tree parms,
6504 tsubst_flags_t complain)
6506 tree parm = TREE_VEC_ELT (parms, parm_idx);
6507 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6510 tree packed_types = NULL_TREE;
6512 if (arg_idx > nargs)
6515 packed_args = make_tree_vec (nargs - arg_idx);
6517 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6518 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6520 /* When the template parameter is a non-type template
6521 parameter pack whose type uses parameter packs, we need
6522 to look at each of the template arguments
6523 separately. Build a vector of the types for these
6524 non-type template parameters in PACKED_TYPES. */
6526 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6527 packed_types = tsubst_pack_expansion (expansion, args,
6530 if (packed_types == error_mark_node)
6531 return error_mark_node;
6533 /* Check that we have the right number of arguments. */
6535 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6536 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6539 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6540 error ("wrong number of template arguments (%d, should be %d)",
6541 nargs, needed_parms);
6542 return error_mark_node;
6545 /* If we aren't able to check the actual arguments now
6546 (because they haven't been expanded yet), we can at least
6547 verify that all of the types used for the non-type
6548 template parameter pack are, in fact, valid for non-type
6549 template parameters. */
6551 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6553 int j, len = TREE_VEC_LENGTH (packed_types);
6554 for (j = 0; j < len; ++j)
6556 tree t = TREE_VEC_ELT (packed_types, j);
6557 if (invalid_nontype_parm_type_p (t, complain))
6558 return error_mark_node;
6563 /* Convert the remaining arguments, which will be a part of the
6564 parameter pack "parm". */
6565 for (; arg_idx < nargs; ++arg_idx)
6567 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6568 tree actual_parm = TREE_VALUE (parm);
6570 if (packed_types && !PACK_EXPANSION_P (arg))
6572 /* When we have a vector of types (corresponding to the
6573 non-type template parameter pack that uses parameter
6574 packs in its type, as mention above), and the
6575 argument is not an expansion (which expands to a
6576 currently unknown number of arguments), clone the
6577 parm and give it the next type in PACKED_TYPES. */
6578 actual_parm = copy_node (actual_parm);
6579 TREE_TYPE (actual_parm) =
6580 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6583 if (arg != error_mark_node)
6584 arg = convert_template_argument (actual_parm,
6585 arg, new_args, complain, parm_idx,
6587 if (arg == error_mark_node)
6589 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6592 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6593 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6594 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6597 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6598 TREE_TYPE (argument_pack)
6599 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6600 TREE_CONSTANT (argument_pack) = 1;
6603 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6604 #ifdef ENABLE_CHECKING
6605 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6606 TREE_VEC_LENGTH (packed_args));
6608 return argument_pack;
6611 /* Convert all template arguments to their appropriate types, and
6612 return a vector containing the innermost resulting template
6613 arguments. If any error occurs, return error_mark_node. Error and
6614 warning messages are issued under control of COMPLAIN.
6616 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6617 for arguments not specified in ARGS. Otherwise, if
6618 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6619 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6620 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6624 coerce_template_parms (tree parms,
6627 tsubst_flags_t complain,
6628 bool require_all_args,
6629 bool use_default_args)
6631 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6634 tree new_inner_args;
6635 int saved_unevaluated_operand;
6636 int saved_inhibit_evaluation_warnings;
6638 /* When used as a boolean value, indicates whether this is a
6639 variadic template parameter list. Since it's an int, we can also
6640 subtract it from nparms to get the number of non-variadic
6643 int post_variadic_parms = 0;
6645 if (args == error_mark_node)
6646 return error_mark_node;
6648 nparms = TREE_VEC_LENGTH (parms);
6650 /* Determine if there are any parameter packs. */
6651 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6653 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6655 ++post_variadic_parms;
6656 if (template_parameter_pack_p (tparm))
6660 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6661 /* If there are no parameters that follow a parameter pack, we need to
6662 expand any argument packs so that we can deduce a parameter pack from
6663 some non-packed args followed by an argument pack, as in variadic85.C.
6664 If there are such parameters, we need to leave argument packs intact
6665 so the arguments are assigned properly. This can happen when dealing
6666 with a nested class inside a partial specialization of a class
6667 template, as in variadic92.C, or when deducing a template parameter pack
6668 from a sub-declarator, as in variadic114.C. */
6669 if (!post_variadic_parms)
6670 inner_args = expand_template_argument_pack (inner_args);
6672 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6673 if ((nargs > nparms && !variadic_p)
6674 || (nargs < nparms - variadic_p
6676 && (!use_default_args
6677 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6678 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6680 if (complain & tf_error)
6684 nparms -= variadic_p;
6685 error ("wrong number of template arguments "
6686 "(%d, should be %d or more)", nargs, nparms);
6689 error ("wrong number of template arguments "
6690 "(%d, should be %d)", nargs, nparms);
6693 error ("provided for %q+D", in_decl);
6696 return error_mark_node;
6699 /* We need to evaluate the template arguments, even though this
6700 template-id may be nested within a "sizeof". */
6701 saved_unevaluated_operand = cp_unevaluated_operand;
6702 cp_unevaluated_operand = 0;
6703 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6704 c_inhibit_evaluation_warnings = 0;
6705 new_inner_args = make_tree_vec (nparms);
6706 new_args = add_outermost_template_args (args, new_inner_args);
6707 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6712 /* Get the Ith template parameter. */
6713 parm = TREE_VEC_ELT (parms, parm_idx);
6715 if (parm == error_mark_node)
6717 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6721 /* Calculate the next argument. */
6722 if (arg_idx < nargs)
6723 arg = TREE_VEC_ELT (inner_args, arg_idx);
6727 if (template_parameter_pack_p (TREE_VALUE (parm))
6728 && !(arg && ARGUMENT_PACK_P (arg)))
6730 /* All remaining arguments will be placed in the
6731 template parameter pack PARM. */
6732 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6733 inner_args, arg_idx,
6737 /* Store this argument. */
6738 if (arg == error_mark_node)
6740 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6742 /* We are done with all of the arguments. */
6749 if (PACK_EXPANSION_P (arg))
6751 /* We don't know how many args we have yet, just
6752 use the unconverted ones for now. */
6753 new_inner_args = args;
6757 else if (require_all_args)
6759 /* There must be a default arg in this case. */
6760 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6762 /* The position of the first default template argument,
6763 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6765 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6766 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6771 if (arg == error_mark_node)
6773 if (complain & tf_error)
6774 error ("template argument %d is invalid", arg_idx + 1);
6777 /* This only occurs if there was an error in the template
6778 parameter list itself (which we would already have
6779 reported) that we are trying to recover from, e.g., a class
6780 template with a parameter list such as
6781 template<typename..., typename>. */
6784 arg = convert_template_argument (TREE_VALUE (parm),
6785 arg, new_args, complain,
6788 if (arg == error_mark_node)
6790 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6792 cp_unevaluated_operand = saved_unevaluated_operand;
6793 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6796 return error_mark_node;
6798 #ifdef ENABLE_CHECKING
6799 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6800 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6801 TREE_VEC_LENGTH (new_inner_args));
6804 return new_inner_args;
6807 /* Returns 1 if template args OT and NT are equivalent. */
6810 template_args_equal (tree ot, tree nt)
6814 if (nt == NULL_TREE || ot == NULL_TREE)
6817 if (TREE_CODE (nt) == TREE_VEC)
6818 /* For member templates */
6819 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6820 else if (PACK_EXPANSION_P (ot))
6821 return PACK_EXPANSION_P (nt)
6822 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6823 PACK_EXPANSION_PATTERN (nt));
6824 else if (ARGUMENT_PACK_P (ot))
6829 if (!ARGUMENT_PACK_P (nt))
6832 opack = ARGUMENT_PACK_ARGS (ot);
6833 npack = ARGUMENT_PACK_ARGS (nt);
6834 len = TREE_VEC_LENGTH (opack);
6835 if (TREE_VEC_LENGTH (npack) != len)
6837 for (i = 0; i < len; ++i)
6838 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6839 TREE_VEC_ELT (npack, i)))
6843 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6845 /* We get here probably because we are in the middle of substituting
6846 into the pattern of a pack expansion. In that case the
6847 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6848 interested in. So we want to use the initial pack argument for
6850 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6851 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6852 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6853 return template_args_equal (ot, nt);
6855 else if (TYPE_P (nt))
6856 return TYPE_P (ot) && same_type_p (ot, nt);
6857 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6860 return cp_tree_equal (ot, nt);
6863 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6864 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6865 NEWARG_PTR with the offending arguments if they are non-NULL. */
6868 comp_template_args_with_info (tree oldargs, tree newargs,
6869 tree *oldarg_ptr, tree *newarg_ptr)
6873 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6876 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6878 tree nt = TREE_VEC_ELT (newargs, i);
6879 tree ot = TREE_VEC_ELT (oldargs, i);
6881 if (! template_args_equal (ot, nt))
6883 if (oldarg_ptr != NULL)
6885 if (newarg_ptr != NULL)
6893 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6894 of template arguments. Returns 0 otherwise. */
6897 comp_template_args (tree oldargs, tree newargs)
6899 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
6903 add_pending_template (tree d)
6905 tree ti = (TYPE_P (d)
6906 ? CLASSTYPE_TEMPLATE_INFO (d)
6907 : DECL_TEMPLATE_INFO (d));
6908 struct pending_template *pt;
6911 if (TI_PENDING_TEMPLATE_FLAG (ti))
6914 /* We are called both from instantiate_decl, where we've already had a
6915 tinst_level pushed, and instantiate_template, where we haven't.
6917 level = !current_tinst_level || current_tinst_level->decl != d;
6920 push_tinst_level (d);
6922 pt = ggc_alloc_pending_template ();
6924 pt->tinst = current_tinst_level;
6925 if (last_pending_template)
6926 last_pending_template->next = pt;
6928 pending_templates = pt;
6930 last_pending_template = pt;
6932 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6939 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6940 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6941 documentation for TEMPLATE_ID_EXPR. */
6944 lookup_template_function (tree fns, tree arglist)
6948 if (fns == error_mark_node || arglist == error_mark_node)
6949 return error_mark_node;
6951 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6953 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
6955 error ("%q#D is not a function template", fns);
6956 return error_mark_node;
6959 if (BASELINK_P (fns))
6961 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6963 BASELINK_FUNCTIONS (fns),
6968 type = TREE_TYPE (fns);
6969 if (TREE_CODE (fns) == OVERLOAD || !type)
6970 type = unknown_type_node;
6972 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6975 /* Within the scope of a template class S<T>, the name S gets bound
6976 (in build_self_reference) to a TYPE_DECL for the class, not a
6977 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6978 or one of its enclosing classes, and that type is a template,
6979 return the associated TEMPLATE_DECL. Otherwise, the original
6982 Also handle the case when DECL is a TREE_LIST of ambiguous
6983 injected-class-names from different bases. */
6986 maybe_get_template_decl_from_type_decl (tree decl)
6988 if (decl == NULL_TREE)
6991 /* DR 176: A lookup that finds an injected-class-name (10.2
6992 [class.member.lookup]) can result in an ambiguity in certain cases
6993 (for example, if it is found in more than one base class). If all of
6994 the injected-class-names that are found refer to specializations of
6995 the same class template, and if the name is followed by a
6996 template-argument-list, the reference refers to the class template
6997 itself and not a specialization thereof, and is not ambiguous. */
6998 if (TREE_CODE (decl) == TREE_LIST)
7000 tree t, tmpl = NULL_TREE;
7001 for (t = decl; t; t = TREE_CHAIN (t))
7003 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7006 else if (tmpl != elt)
7009 if (tmpl && t == NULL_TREE)
7015 return (decl != NULL_TREE
7016 && DECL_SELF_REFERENCE_P (decl)
7017 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7018 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7021 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7022 parameters, find the desired type.
7024 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7026 IN_DECL, if non-NULL, is the template declaration we are trying to
7029 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7030 the class we are looking up.
7032 Issue error and warning messages under control of COMPLAIN.
7034 If the template class is really a local class in a template
7035 function, then the FUNCTION_CONTEXT is the function in which it is
7038 ??? Note that this function is currently called *twice* for each
7039 template-id: the first time from the parser, while creating the
7040 incomplete type (finish_template_type), and the second type during the
7041 real instantiation (instantiate_template_class). This is surely something
7042 that we want to avoid. It also causes some problems with argument
7043 coercion (see convert_nontype_argument for more information on this). */
7046 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7047 int entering_scope, tsubst_flags_t complain)
7049 tree templ = NULL_TREE, parmlist;
7056 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7058 tree value = innermost_non_namespace_value (d1);
7059 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7064 push_decl_namespace (context);
7065 templ = lookup_name (d1);
7066 templ = maybe_get_template_decl_from_type_decl (templ);
7068 pop_decl_namespace ();
7071 context = DECL_CONTEXT (templ);
7073 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7075 tree type = TREE_TYPE (d1);
7077 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7078 an implicit typename for the second A. Deal with it. */
7079 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7080 type = TREE_TYPE (type);
7082 if (CLASSTYPE_TEMPLATE_INFO (type))
7084 templ = CLASSTYPE_TI_TEMPLATE (type);
7085 d1 = DECL_NAME (templ);
7088 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7089 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7091 templ = TYPE_TI_TEMPLATE (d1);
7092 d1 = DECL_NAME (templ);
7094 else if (TREE_CODE (d1) == TEMPLATE_DECL
7095 && DECL_TEMPLATE_RESULT (d1)
7096 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7099 d1 = DECL_NAME (templ);
7100 context = DECL_CONTEXT (templ);
7103 /* Issue an error message if we didn't find a template. */
7106 if (complain & tf_error)
7107 error ("%qT is not a template", d1);
7108 return error_mark_node;
7111 if (TREE_CODE (templ) != TEMPLATE_DECL
7112 /* Make sure it's a user visible template, if it was named by
7114 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7115 && !PRIMARY_TEMPLATE_P (templ)))
7117 if (complain & tf_error)
7119 error ("non-template type %qT used as a template", d1);
7121 error ("for template declaration %q+D", in_decl);
7123 return error_mark_node;
7126 complain &= ~tf_user;
7128 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7130 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7131 template arguments */
7137 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7139 /* Consider an example where a template template parameter declared as
7141 template <class T, class U = std::allocator<T> > class TT
7143 The template parameter level of T and U are one level larger than
7144 of TT. To proper process the default argument of U, say when an
7145 instantiation `TT<int>' is seen, we need to build the full
7146 arguments containing {int} as the innermost level. Outer levels,
7147 available when not appearing as default template argument, can be
7148 obtained from the arguments of the enclosing template.
7150 Suppose that TT is later substituted with std::vector. The above
7151 instantiation is `TT<int, std::allocator<T> >' with TT at
7152 level 1, and T at level 2, while the template arguments at level 1
7153 becomes {std::vector} and the inner level 2 is {int}. */
7155 outer = DECL_CONTEXT (templ);
7157 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7158 else if (current_template_parms)
7159 /* This is an argument of the current template, so we haven't set
7160 DECL_CONTEXT yet. */
7161 outer = current_template_args ();
7164 arglist = add_to_template_args (outer, arglist);
7166 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7168 /*require_all_args=*/true,
7169 /*use_default_args=*/true);
7170 if (arglist2 == error_mark_node
7171 || (!uses_template_parms (arglist2)
7172 && check_instantiated_args (templ, arglist2, complain)))
7173 return error_mark_node;
7175 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7180 tree template_type = TREE_TYPE (templ);
7183 tree found = NULL_TREE;
7186 int is_dependent_type;
7187 int use_partial_inst_tmpl = false;
7189 gen_tmpl = most_general_template (templ);
7190 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7191 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7192 arg_depth = TMPL_ARGS_DEPTH (arglist);
7194 if (arg_depth == 1 && parm_depth > 1)
7196 /* We've been given an incomplete set of template arguments.
7199 template <class T> struct S1 {
7200 template <class U> struct S2 {};
7201 template <class U> struct S2<U*> {};
7204 we will be called with an ARGLIST of `U*', but the
7205 TEMPLATE will be `template <class T> template
7206 <class U> struct S1<T>::S2'. We must fill in the missing
7209 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7211 arg_depth = TMPL_ARGS_DEPTH (arglist);
7214 /* Now we should have enough arguments. */
7215 gcc_assert (parm_depth == arg_depth);
7217 /* From here on, we're only interested in the most general
7220 /* Calculate the BOUND_ARGS. These will be the args that are
7221 actually tsubst'd into the definition to create the
7225 /* We have multiple levels of arguments to coerce, at once. */
7227 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7229 tree bound_args = make_tree_vec (parm_depth);
7231 for (i = saved_depth,
7232 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7233 i > 0 && t != NULL_TREE;
7234 --i, t = TREE_CHAIN (t))
7237 if (i == saved_depth)
7238 a = coerce_template_parms (TREE_VALUE (t),
7241 /*require_all_args=*/true,
7242 /*use_default_args=*/true);
7244 /* Outer levels should have already been coerced. */
7245 a = TMPL_ARGS_LEVEL (arglist, i);
7247 /* Don't process further if one of the levels fails. */
7248 if (a == error_mark_node)
7250 /* Restore the ARGLIST to its full size. */
7251 TREE_VEC_LENGTH (arglist) = saved_depth;
7252 return error_mark_node;
7255 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7257 /* We temporarily reduce the length of the ARGLIST so
7258 that coerce_template_parms will see only the arguments
7259 corresponding to the template parameters it is
7261 TREE_VEC_LENGTH (arglist)--;
7264 /* Restore the ARGLIST to its full size. */
7265 TREE_VEC_LENGTH (arglist) = saved_depth;
7267 arglist = bound_args;
7271 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7272 INNERMOST_TEMPLATE_ARGS (arglist),
7275 /*require_all_args=*/true,
7276 /*use_default_args=*/true);
7278 if (arglist == error_mark_node)
7279 /* We were unable to bind the arguments. */
7280 return error_mark_node;
7282 /* In the scope of a template class, explicit references to the
7283 template class refer to the type of the template, not any
7284 instantiation of it. For example, in:
7286 template <class T> class C { void f(C<T>); }
7288 the `C<T>' is just the same as `C'. Outside of the
7289 class, however, such a reference is an instantiation. */
7291 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7292 || currently_open_class (template_type))
7293 /* comp_template_args is expensive, check it last. */
7294 && comp_template_args (TYPE_TI_ARGS (template_type),
7296 return template_type;
7298 /* If we already have this specialization, return it. */
7299 elt.tmpl = gen_tmpl;
7301 hash = hash_specialization (&elt);
7302 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7308 is_dependent_type = uses_template_parms (arglist);
7310 /* If the deduced arguments are invalid, then the binding
7312 if (!is_dependent_type
7313 && check_instantiated_args (gen_tmpl,
7314 INNERMOST_TEMPLATE_ARGS (arglist),
7316 return error_mark_node;
7318 if (!is_dependent_type
7319 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7320 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7321 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7323 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7324 DECL_NAME (gen_tmpl),
7325 /*tag_scope=*/ts_global);
7329 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7332 context = global_namespace;
7334 /* Create the type. */
7335 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7337 if (!is_dependent_type)
7339 set_current_access_from_decl (TYPE_NAME (template_type));
7340 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7341 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7342 arglist, complain, in_decl),
7343 SCOPED_ENUM_P (template_type), NULL);
7347 /* We don't want to call start_enum for this type, since
7348 the values for the enumeration constants may involve
7349 template parameters. And, no one should be interested
7350 in the enumeration constants for such a type. */
7351 t = cxx_make_type (ENUMERAL_TYPE);
7352 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7354 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7355 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7356 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7360 t = make_class_type (TREE_CODE (template_type));
7361 CLASSTYPE_DECLARED_CLASS (t)
7362 = CLASSTYPE_DECLARED_CLASS (template_type);
7363 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7364 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7366 /* A local class. Make sure the decl gets registered properly. */
7367 if (context == current_function_decl)
7368 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7370 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7371 /* This instantiation is another name for the primary
7372 template type. Set the TYPE_CANONICAL field
7374 TYPE_CANONICAL (t) = template_type;
7375 else if (any_template_arguments_need_structural_equality_p (arglist))
7376 /* Some of the template arguments require structural
7377 equality testing, so this template class requires
7378 structural equality testing. */
7379 SET_TYPE_STRUCTURAL_EQUALITY (t);
7382 /* If we called start_enum or pushtag above, this information
7383 will already be set up. */
7386 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7388 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7389 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7390 DECL_SOURCE_LOCATION (type_decl)
7391 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7394 type_decl = TYPE_NAME (t);
7396 TREE_PRIVATE (type_decl)
7397 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7398 TREE_PROTECTED (type_decl)
7399 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7400 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7402 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7403 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7406 /* Let's consider the explicit specialization of a member
7407 of a class template specialization that is implicitely instantiated,
7412 template<class U> struct M {}; //#0
7417 struct S<int>::M<char> //#1
7421 [temp.expl.spec]/4 says this is valid.
7423 In this case, when we write:
7426 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7429 When we encounter #1, we want to store the partial instantiation
7430 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7432 For all cases other than this "explicit specialization of member of a
7433 class template", we just want to store the most general template into
7434 the CLASSTYPE_TI_TEMPLATE of M.
7436 This case of "explicit specialization of member of a class template"
7438 1/ the enclosing class is an instantiation of, and therefore not
7439 the same as, the context of the most general template, and
7440 2/ we aren't looking at the partial instantiation itself, i.e.
7441 the innermost arguments are not the same as the innermost parms of
7442 the most general template.
7444 So it's only when 1/ and 2/ happens that we want to use the partial
7445 instantiation of the member template in lieu of its most general
7448 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7449 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7450 /* the enclosing class must be an instantiation... */
7451 && CLASS_TYPE_P (context)
7452 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7454 tree partial_inst_args;
7455 TREE_VEC_LENGTH (arglist)--;
7456 ++processing_template_decl;
7458 tsubst (INNERMOST_TEMPLATE_ARGS
7459 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7460 arglist, complain, NULL_TREE);
7461 --processing_template_decl;
7462 TREE_VEC_LENGTH (arglist)++;
7463 use_partial_inst_tmpl =
7464 /*...and we must not be looking at the partial instantiation
7466 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7470 if (!use_partial_inst_tmpl)
7471 /* This case is easy; there are no member templates involved. */
7475 /* This is a full instantiation of a member template. Find
7476 the partial instantiation of which this is an instance. */
7478 /* Temporarily reduce by one the number of levels in the ARGLIST
7479 so as to avoid comparing the last set of arguments. */
7480 TREE_VEC_LENGTH (arglist)--;
7481 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7482 TREE_VEC_LENGTH (arglist)++;
7483 found = CLASSTYPE_TI_TEMPLATE (found);
7486 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7489 slot = htab_find_slot_with_hash (type_specializations,
7490 &elt, hash, INSERT);
7491 entry = ggc_alloc_spec_entry ();
7495 /* Note this use of the partial instantiation so we can check it
7496 later in maybe_process_partial_specialization. */
7497 DECL_TEMPLATE_INSTANTIATIONS (templ)
7498 = tree_cons (arglist, t,
7499 DECL_TEMPLATE_INSTANTIATIONS (templ));
7501 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7502 /* Now that the type has been registered on the instantiations
7503 list, we set up the enumerators. Because the enumeration
7504 constants may involve the enumeration type itself, we make
7505 sure to register the type first, and then create the
7506 constants. That way, doing tsubst_expr for the enumeration
7507 constants won't result in recursive calls here; we'll find
7508 the instantiation and exit above. */
7509 tsubst_enum (template_type, t, arglist);
7511 if (is_dependent_type)
7512 /* If the type makes use of template parameters, the
7513 code that generates debugging information will crash. */
7514 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7516 /* Possibly limit visibility based on template args. */
7517 TREE_PUBLIC (type_decl) = 1;
7518 determine_visibility (type_decl);
7524 /* Wrapper for lookup_template_class_1. */
7527 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7528 int entering_scope, tsubst_flags_t complain)
7531 timevar_push (TV_TEMPLATE_INST);
7532 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7533 entering_scope, complain);
7534 timevar_pop (TV_TEMPLATE_INST);
7542 /* True when we should also visit template parameters that occur in
7543 non-deduced contexts. */
7544 bool include_nondeduced_p;
7545 struct pointer_set_t *visited;
7548 /* Called from for_each_template_parm via walk_tree. */
7551 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7554 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7555 tree_fn_t fn = pfd->fn;
7556 void *data = pfd->data;
7559 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7560 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7561 pfd->include_nondeduced_p))
7562 return error_mark_node;
7564 switch (TREE_CODE (t))
7567 if (TYPE_PTRMEMFUNC_P (t))
7573 if (!TYPE_TEMPLATE_INFO (t))
7575 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7576 fn, data, pfd->visited,
7577 pfd->include_nondeduced_p))
7578 return error_mark_node;
7582 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7583 fn, data, pfd->visited,
7584 pfd->include_nondeduced_p)
7585 || for_each_template_parm (TYPE_MAX_VALUE (t),
7586 fn, data, pfd->visited,
7587 pfd->include_nondeduced_p))
7588 return error_mark_node;
7592 /* Since we're not going to walk subtrees, we have to do this
7594 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7595 pfd->visited, pfd->include_nondeduced_p))
7596 return error_mark_node;
7600 /* Check the return type. */
7601 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7602 pfd->include_nondeduced_p))
7603 return error_mark_node;
7605 /* Check the parameter types. Since default arguments are not
7606 instantiated until they are needed, the TYPE_ARG_TYPES may
7607 contain expressions that involve template parameters. But,
7608 no-one should be looking at them yet. And, once they're
7609 instantiated, they don't contain template parameters, so
7610 there's no point in looking at them then, either. */
7614 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7615 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7616 pfd->visited, pfd->include_nondeduced_p))
7617 return error_mark_node;
7619 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7620 want walk_tree walking into them itself. */
7626 case UNDERLYING_TYPE:
7627 if (pfd->include_nondeduced_p
7628 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7630 pfd->include_nondeduced_p))
7631 return error_mark_node;
7636 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7637 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7638 pfd->visited, pfd->include_nondeduced_p))
7639 return error_mark_node;
7644 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7645 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7646 pfd->visited, pfd->include_nondeduced_p))
7647 return error_mark_node;
7648 if (DECL_CONTEXT (t)
7649 && pfd->include_nondeduced_p
7650 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7651 pfd->visited, pfd->include_nondeduced_p))
7652 return error_mark_node;
7655 case BOUND_TEMPLATE_TEMPLATE_PARM:
7656 /* Record template parameters such as `T' inside `TT<T>'. */
7657 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7658 pfd->include_nondeduced_p))
7659 return error_mark_node;
7662 case TEMPLATE_TEMPLATE_PARM:
7663 case TEMPLATE_TYPE_PARM:
7664 case TEMPLATE_PARM_INDEX:
7665 if (fn && (*fn)(t, data))
7666 return error_mark_node;
7668 return error_mark_node;
7672 /* A template template parameter is encountered. */
7673 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7674 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7675 pfd->include_nondeduced_p))
7676 return error_mark_node;
7678 /* Already substituted template template parameter */
7684 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7686 pfd->include_nondeduced_p))
7687 return error_mark_node;
7691 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7692 && pfd->include_nondeduced_p
7693 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7694 (TREE_TYPE (t)), fn, data,
7695 pfd->visited, pfd->include_nondeduced_p))
7696 return error_mark_node;
7701 /* If there's no type, then this thing must be some expression
7702 involving template parameters. */
7703 if (!fn && !TREE_TYPE (t))
7704 return error_mark_node;
7709 case IMPLICIT_CONV_EXPR:
7710 case REINTERPRET_CAST_EXPR:
7711 case CONST_CAST_EXPR:
7712 case STATIC_CAST_EXPR:
7713 case DYNAMIC_CAST_EXPR:
7717 case PSEUDO_DTOR_EXPR:
7719 return error_mark_node;
7726 /* We didn't find any template parameters we liked. */
7730 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7731 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7732 call FN with the parameter and the DATA.
7733 If FN returns nonzero, the iteration is terminated, and
7734 for_each_template_parm returns 1. Otherwise, the iteration
7735 continues. If FN never returns a nonzero value, the value
7736 returned by for_each_template_parm is 0. If FN is NULL, it is
7737 considered to be the function which always returns 1.
7739 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7740 parameters that occur in non-deduced contexts. When false, only
7741 visits those template parameters that can be deduced. */
7744 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7745 struct pointer_set_t *visited,
7746 bool include_nondeduced_p)
7748 struct pair_fn_data pfd;
7754 pfd.include_nondeduced_p = include_nondeduced_p;
7756 /* Walk the tree. (Conceptually, we would like to walk without
7757 duplicates, but for_each_template_parm_r recursively calls
7758 for_each_template_parm, so we would need to reorganize a fair
7759 bit to use walk_tree_without_duplicates, so we keep our own
7762 pfd.visited = visited;
7764 pfd.visited = pointer_set_create ();
7765 result = cp_walk_tree (&t,
7766 for_each_template_parm_r,
7768 pfd.visited) != NULL_TREE;
7773 pointer_set_destroy (pfd.visited);
7780 /* Returns true if T depends on any template parameter. */
7783 uses_template_parms (tree t)
7786 int saved_processing_template_decl;
7788 saved_processing_template_decl = processing_template_decl;
7789 if (!saved_processing_template_decl)
7790 processing_template_decl = 1;
7792 dependent_p = dependent_type_p (t);
7793 else if (TREE_CODE (t) == TREE_VEC)
7794 dependent_p = any_dependent_template_arguments_p (t);
7795 else if (TREE_CODE (t) == TREE_LIST)
7796 dependent_p = (uses_template_parms (TREE_VALUE (t))
7797 || uses_template_parms (TREE_CHAIN (t)));
7798 else if (TREE_CODE (t) == TYPE_DECL)
7799 dependent_p = dependent_type_p (TREE_TYPE (t));
7802 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7803 || TREE_CODE (t) == OVERLOAD
7805 || TREE_CODE (t) == IDENTIFIER_NODE
7806 || TREE_CODE (t) == TRAIT_EXPR
7807 || TREE_CODE (t) == CONSTRUCTOR
7808 || CONSTANT_CLASS_P (t))
7809 dependent_p = (type_dependent_expression_p (t)
7810 || value_dependent_expression_p (t));
7813 gcc_assert (t == error_mark_node);
7814 dependent_p = false;
7817 processing_template_decl = saved_processing_template_decl;
7822 /* Returns true if T depends on any template parameter with level LEVEL. */
7825 uses_template_parms_level (tree t, int level)
7827 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7828 /*include_nondeduced_p=*/true);
7831 /* Returns TRUE iff INST is an instantiation we don't need to do in an
7832 ill-formed translation unit, i.e. a variable or function that isn't
7833 usable in a constant expression. */
7836 neglectable_inst_p (tree d)
7839 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
7840 : decl_maybe_constant_var_p (d)));
7843 /* Returns TRUE iff we should refuse to instantiate DECL because it's
7844 neglectable and instantiated from within an erroneous instantiation. */
7847 limit_bad_template_recursion (tree decl)
7849 struct tinst_level *lev = current_tinst_level;
7850 int errs = errorcount + sorrycount;
7851 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
7854 for (; lev; lev = lev->next)
7855 if (neglectable_inst_p (lev->decl))
7858 return (lev && errs > lev->errors);
7861 static int tinst_depth;
7862 extern int max_tinst_depth;
7863 #ifdef GATHER_STATISTICS
7866 static GTY(()) struct tinst_level *last_error_tinst_level;
7868 /* We're starting to instantiate D; record the template instantiation context
7869 for diagnostics and to restore it later. */
7872 push_tinst_level (tree d)
7874 struct tinst_level *new_level;
7876 if (tinst_depth >= max_tinst_depth)
7878 last_error_tinst_level = current_tinst_level;
7879 if (TREE_CODE (d) == TREE_LIST)
7880 error ("template instantiation depth exceeds maximum of %d (use "
7881 "-ftemplate-depth= to increase the maximum) substituting %qS",
7882 max_tinst_depth, d);
7884 error ("template instantiation depth exceeds maximum of %d (use "
7885 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7886 max_tinst_depth, d);
7888 print_instantiation_context ();
7893 /* If the current instantiation caused problems, don't let it instantiate
7894 anything else. Do allow deduction substitution and decls usable in
7895 constant expressions. */
7896 if (limit_bad_template_recursion (d))
7899 new_level = ggc_alloc_tinst_level ();
7900 new_level->decl = d;
7901 new_level->locus = input_location;
7902 new_level->errors = errorcount+sorrycount;
7903 new_level->in_system_header_p = in_system_header;
7904 new_level->next = current_tinst_level;
7905 current_tinst_level = new_level;
7908 #ifdef GATHER_STATISTICS
7909 if (tinst_depth > depth_reached)
7910 depth_reached = tinst_depth;
7916 /* We're done instantiating this template; return to the instantiation
7920 pop_tinst_level (void)
7922 /* Restore the filename and line number stashed away when we started
7923 this instantiation. */
7924 input_location = current_tinst_level->locus;
7925 current_tinst_level = current_tinst_level->next;
7929 /* We're instantiating a deferred template; restore the template
7930 instantiation context in which the instantiation was requested, which
7931 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7934 reopen_tinst_level (struct tinst_level *level)
7936 struct tinst_level *t;
7939 for (t = level; t; t = t->next)
7942 current_tinst_level = level;
7944 if (current_tinst_level)
7945 current_tinst_level->errors = errorcount+sorrycount;
7949 /* Returns the TINST_LEVEL which gives the original instantiation
7952 struct tinst_level *
7953 outermost_tinst_level (void)
7955 struct tinst_level *level = current_tinst_level;
7958 level = level->next;
7962 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7965 parameter_of_template_p (tree parm, tree templ)
7970 if (!parm || !templ)
7973 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7974 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7976 parms = DECL_TEMPLATE_PARMS (templ);
7977 parms = INNERMOST_TEMPLATE_PARMS (parms);
7979 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7981 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
7983 || (DECL_INITIAL (parm)
7984 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
7991 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7992 vector of template arguments, as for tsubst.
7994 Returns an appropriate tsubst'd friend declaration. */
7997 tsubst_friend_function (tree decl, tree args)
8001 if (TREE_CODE (decl) == FUNCTION_DECL
8002 && DECL_TEMPLATE_INSTANTIATION (decl)
8003 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8004 /* This was a friend declared with an explicit template
8005 argument list, e.g.:
8009 to indicate that f was a template instantiation, not a new
8010 function declaration. Now, we have to figure out what
8011 instantiation of what template. */
8013 tree template_id, arglist, fns;
8016 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8018 /* Friend functions are looked up in the containing namespace scope.
8019 We must enter that scope, to avoid finding member functions of the
8020 current class with same name. */
8021 push_nested_namespace (ns);
8022 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8023 tf_warning_or_error, NULL_TREE,
8024 /*integral_constant_expression_p=*/false);
8025 pop_nested_namespace (ns);
8026 arglist = tsubst (DECL_TI_ARGS (decl), args,
8027 tf_warning_or_error, NULL_TREE);
8028 template_id = lookup_template_function (fns, arglist);
8030 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8031 tmpl = determine_specialization (template_id, new_friend,
8033 /*need_member_template=*/0,
8034 TREE_VEC_LENGTH (args),
8036 return instantiate_template (tmpl, new_args, tf_error);
8039 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8041 /* The NEW_FRIEND will look like an instantiation, to the
8042 compiler, but is not an instantiation from the point of view of
8043 the language. For example, we might have had:
8045 template <class T> struct S {
8046 template <class U> friend void f(T, U);
8049 Then, in S<int>, template <class U> void f(int, U) is not an
8050 instantiation of anything. */
8051 if (new_friend == error_mark_node)
8052 return error_mark_node;
8054 DECL_USE_TEMPLATE (new_friend) = 0;
8055 if (TREE_CODE (decl) == TEMPLATE_DECL)
8057 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8058 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8059 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8062 /* The mangled name for the NEW_FRIEND is incorrect. The function
8063 is not a template instantiation and should not be mangled like
8064 one. Therefore, we forget the mangling here; we'll recompute it
8065 later if we need it. */
8066 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8068 SET_DECL_RTL (new_friend, NULL);
8069 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8072 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8075 tree new_friend_template_info;
8076 tree new_friend_result_template_info;
8078 int new_friend_is_defn;
8080 /* We must save some information from NEW_FRIEND before calling
8081 duplicate decls since that function will free NEW_FRIEND if
8083 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8084 new_friend_is_defn =
8085 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8086 (template_for_substitution (new_friend)))
8088 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8090 /* This declaration is a `primary' template. */
8091 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8093 new_friend_result_template_info
8094 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8097 new_friend_result_template_info = NULL_TREE;
8099 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8100 if (new_friend_is_defn)
8101 DECL_INITIAL (new_friend) = error_mark_node;
8103 /* Inside pushdecl_namespace_level, we will push into the
8104 current namespace. However, the friend function should go
8105 into the namespace of the template. */
8106 ns = decl_namespace_context (new_friend);
8107 push_nested_namespace (ns);
8108 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8109 pop_nested_namespace (ns);
8111 if (old_decl == error_mark_node)
8112 return error_mark_node;
8114 if (old_decl != new_friend)
8116 /* This new friend declaration matched an existing
8117 declaration. For example, given:
8119 template <class T> void f(T);
8120 template <class U> class C {
8121 template <class T> friend void f(T) {}
8124 the friend declaration actually provides the definition
8125 of `f', once C has been instantiated for some type. So,
8126 old_decl will be the out-of-class template declaration,
8127 while new_friend is the in-class definition.
8129 But, if `f' was called before this point, the
8130 instantiation of `f' will have DECL_TI_ARGS corresponding
8131 to `T' but not to `U', references to which might appear
8132 in the definition of `f'. Previously, the most general
8133 template for an instantiation of `f' was the out-of-class
8134 version; now it is the in-class version. Therefore, we
8135 run through all specialization of `f', adding to their
8136 DECL_TI_ARGS appropriately. In particular, they need a
8137 new set of outer arguments, corresponding to the
8138 arguments for this class instantiation.
8140 The same situation can arise with something like this:
8143 template <class T> class C {
8147 when `C<int>' is instantiated. Now, `f(int)' is defined
8150 if (!new_friend_is_defn)
8151 /* On the other hand, if the in-class declaration does
8152 *not* provide a definition, then we don't want to alter
8153 existing definitions. We can just leave everything
8158 tree new_template = TI_TEMPLATE (new_friend_template_info);
8159 tree new_args = TI_ARGS (new_friend_template_info);
8161 /* Overwrite whatever template info was there before, if
8162 any, with the new template information pertaining to
8164 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8166 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8168 /* We should have called reregister_specialization in
8170 gcc_assert (retrieve_specialization (new_template,
8174 /* Instantiate it if the global has already been used. */
8175 if (DECL_ODR_USED (old_decl))
8176 instantiate_decl (old_decl, /*defer_ok=*/true,
8177 /*expl_inst_class_mem_p=*/false);
8183 /* Indicate that the old function template is a partial
8185 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8186 = new_friend_result_template_info;
8188 gcc_assert (new_template
8189 == most_general_template (new_template));
8190 gcc_assert (new_template != old_decl);
8192 /* Reassign any specializations already in the hash table
8193 to the new more general template, and add the
8194 additional template args. */
8195 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8199 tree spec = TREE_VALUE (t);
8202 elt.tmpl = old_decl;
8203 elt.args = DECL_TI_ARGS (spec);
8204 elt.spec = NULL_TREE;
8206 htab_remove_elt (decl_specializations, &elt);
8209 = add_outermost_template_args (new_args,
8210 DECL_TI_ARGS (spec));
8212 register_specialization
8213 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8216 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8220 /* The information from NEW_FRIEND has been merged into OLD_DECL
8221 by duplicate_decls. */
8222 new_friend = old_decl;
8227 tree context = DECL_CONTEXT (new_friend);
8231 template <class T> class C {
8232 template <class U> friend void C1<U>::f (); // case 1
8233 friend void C2<T>::f (); // case 2
8235 we only need to make sure CONTEXT is a complete type for
8236 case 2. To distinguish between the two cases, we note that
8237 CONTEXT of case 1 remains dependent type after tsubst while
8238 this isn't true for case 2. */
8239 ++processing_template_decl;
8240 dependent_p = dependent_type_p (context);
8241 --processing_template_decl;
8244 && !complete_type_or_else (context, NULL_TREE))
8245 return error_mark_node;
8247 if (COMPLETE_TYPE_P (context))
8249 /* Check to see that the declaration is really present, and,
8250 possibly obtain an improved declaration. */
8251 tree fn = check_classfn (context,
8252 new_friend, NULL_TREE);
8262 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8263 template arguments, as for tsubst.
8265 Returns an appropriate tsubst'd friend type or error_mark_node on
8269 tsubst_friend_class (tree friend_tmpl, tree args)
8275 context = CP_DECL_CONTEXT (friend_tmpl);
8277 if (context != global_namespace)
8279 if (TREE_CODE (context) == NAMESPACE_DECL)
8280 push_nested_namespace (context);
8282 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8285 /* Look for a class template declaration. We look for hidden names
8286 because two friend declarations of the same template are the
8287 same. For example, in:
8290 template <typename> friend class F;
8292 template <typename> struct B {
8293 template <typename> friend class F;
8296 both F templates are the same. */
8297 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8298 /*block_p=*/true, 0,
8299 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8301 /* But, if we don't find one, it might be because we're in a
8302 situation like this:
8310 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8311 for `S<int>', not the TEMPLATE_DECL. */
8312 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8314 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8315 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8318 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8320 /* The friend template has already been declared. Just
8321 check to see that the declarations match, and install any new
8322 default parameters. We must tsubst the default parameters,
8323 of course. We only need the innermost template parameters
8324 because that is all that redeclare_class_template will look
8326 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8327 > TMPL_ARGS_DEPTH (args))
8330 location_t saved_input_location;
8331 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8332 args, tf_warning_or_error);
8334 saved_input_location = input_location;
8335 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8336 redeclare_class_template (TREE_TYPE (tmpl), parms);
8337 input_location = saved_input_location;
8341 friend_type = TREE_TYPE (tmpl);
8345 /* The friend template has not already been declared. In this
8346 case, the instantiation of the template class will cause the
8347 injection of this template into the global scope. */
8348 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8349 if (tmpl == error_mark_node)
8350 return error_mark_node;
8352 /* The new TMPL is not an instantiation of anything, so we
8353 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8354 the new type because that is supposed to be the corresponding
8355 template decl, i.e., TMPL. */
8356 DECL_USE_TEMPLATE (tmpl) = 0;
8357 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8358 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8359 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8360 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8362 /* Inject this template into the global scope. */
8363 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8366 if (context != global_namespace)
8368 if (TREE_CODE (context) == NAMESPACE_DECL)
8369 pop_nested_namespace (context);
8371 pop_nested_class ();
8377 /* Returns zero if TYPE cannot be completed later due to circularity.
8378 Otherwise returns one. */
8381 can_complete_type_without_circularity (tree type)
8383 if (type == NULL_TREE || type == error_mark_node)
8385 else if (COMPLETE_TYPE_P (type))
8387 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8388 return can_complete_type_without_circularity (TREE_TYPE (type));
8389 else if (CLASS_TYPE_P (type)
8390 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8396 /* Apply any attributes which had to be deferred until instantiation
8397 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8398 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8401 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8402 tree args, tsubst_flags_t complain, tree in_decl)
8404 tree last_dep = NULL_TREE;
8408 for (t = attributes; t; t = TREE_CHAIN (t))
8409 if (ATTR_IS_DEPENDENT (t))
8412 attributes = copy_list (attributes);
8416 if (DECL_P (*decl_p))
8418 if (TREE_TYPE (*decl_p) == error_mark_node)
8420 p = &DECL_ATTRIBUTES (*decl_p);
8423 p = &TYPE_ATTRIBUTES (*decl_p);
8427 tree late_attrs = NULL_TREE;
8428 tree *q = &late_attrs;
8430 for (*p = attributes; *p; )
8433 if (ATTR_IS_DEPENDENT (t))
8435 *p = TREE_CHAIN (t);
8436 TREE_CHAIN (t) = NULL_TREE;
8437 /* If the first attribute argument is an identifier, don't
8438 pass it through tsubst. Attributes like mode, format,
8439 cleanup and several target specific attributes expect it
8442 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8443 && TREE_VALUE (TREE_VALUE (t))
8444 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8445 == IDENTIFIER_NODE))
8448 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8450 /*integral_constant_expression_p=*/false);
8451 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8453 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8458 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8459 /*integral_constant_expression_p=*/false);
8461 q = &TREE_CHAIN (t);
8464 p = &TREE_CHAIN (t);
8467 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8471 /* Perform (or defer) access check for typedefs that were referenced
8472 from within the template TMPL code.
8473 This is a subroutine of instantiate_template and instantiate_class_template.
8474 TMPL is the template to consider and TARGS is the list of arguments of
8478 perform_typedefs_access_check (tree tmpl, tree targs)
8480 location_t saved_location;
8482 qualified_typedef_usage_t *iter;
8485 || (!CLASS_TYPE_P (tmpl)
8486 && TREE_CODE (tmpl) != FUNCTION_DECL))
8489 saved_location = input_location;
8490 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8491 get_types_needing_access_check (tmpl),
8494 tree type_decl = iter->typedef_decl;
8495 tree type_scope = iter->context;
8497 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8500 if (uses_template_parms (type_decl))
8501 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8502 if (uses_template_parms (type_scope))
8503 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8505 /* Make access check error messages point to the location
8506 of the use of the typedef. */
8507 input_location = iter->locus;
8508 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8509 type_decl, type_decl);
8511 input_location = saved_location;
8515 instantiate_class_template_1 (tree type)
8517 tree templ, args, pattern, t, member;
8521 unsigned int saved_maximum_field_alignment;
8523 if (type == error_mark_node)
8524 return error_mark_node;
8526 if (COMPLETE_OR_OPEN_TYPE_P (type)
8527 || uses_template_parms (type))
8530 /* Figure out which template is being instantiated. */
8531 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8532 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8534 /* Determine what specialization of the original template to
8536 t = most_specialized_class (type, templ, tf_warning_or_error);
8537 if (t == error_mark_node)
8539 TYPE_BEING_DEFINED (type) = 1;
8540 return error_mark_node;
8544 /* This TYPE is actually an instantiation of a partial
8545 specialization. We replace the innermost set of ARGS with
8546 the arguments appropriate for substitution. For example,
8549 template <class T> struct S {};
8550 template <class T> struct S<T*> {};
8552 and supposing that we are instantiating S<int*>, ARGS will
8553 presently be {int*} -- but we need {int}. */
8554 pattern = TREE_TYPE (t);
8555 args = TREE_PURPOSE (t);
8559 pattern = TREE_TYPE (templ);
8560 args = CLASSTYPE_TI_ARGS (type);
8563 /* If the template we're instantiating is incomplete, then clearly
8564 there's nothing we can do. */
8565 if (!COMPLETE_TYPE_P (pattern))
8568 /* If we've recursively instantiated too many templates, stop. */
8569 if (! push_tinst_level (type))
8572 /* Now we're really doing the instantiation. Mark the type as in
8573 the process of being defined. */
8574 TYPE_BEING_DEFINED (type) = 1;
8576 /* We may be in the middle of deferred access check. Disable
8578 push_deferring_access_checks (dk_no_deferred);
8580 push_to_top_level ();
8581 /* Use #pragma pack from the template context. */
8582 saved_maximum_field_alignment = maximum_field_alignment;
8583 maximum_field_alignment = TYPE_PRECISION (pattern);
8585 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8587 /* Set the input location to the most specialized template definition.
8588 This is needed if tsubsting causes an error. */
8589 typedecl = TYPE_MAIN_DECL (pattern);
8590 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8591 DECL_SOURCE_LOCATION (typedecl);
8593 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8594 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8595 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8596 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8597 if (ANON_AGGR_TYPE_P (pattern))
8598 SET_ANON_AGGR_TYPE_P (type);
8599 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8601 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8602 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8604 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8606 pbinfo = TYPE_BINFO (pattern);
8608 /* We should never instantiate a nested class before its enclosing
8609 class; we need to look up the nested class by name before we can
8610 instantiate it, and that lookup should instantiate the enclosing
8612 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8613 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8615 base_list = NULL_TREE;
8616 if (BINFO_N_BASE_BINFOS (pbinfo))
8622 /* We must enter the scope containing the type, as that is where
8623 the accessibility of types named in dependent bases are
8625 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8627 /* Substitute into each of the bases to determine the actual
8629 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8632 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8633 tree expanded_bases = NULL_TREE;
8636 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8639 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8640 args, tf_error, NULL_TREE);
8641 if (expanded_bases == error_mark_node)
8644 len = TREE_VEC_LENGTH (expanded_bases);
8647 for (idx = 0; idx < len; idx++)
8650 /* Extract the already-expanded base class. */
8651 base = TREE_VEC_ELT (expanded_bases, idx);
8653 /* Substitute to figure out the base class. */
8654 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8657 if (base == error_mark_node)
8660 base_list = tree_cons (access, base, base_list);
8661 if (BINFO_VIRTUAL_P (pbase_binfo))
8662 TREE_TYPE (base_list) = integer_type_node;
8666 /* The list is now in reverse order; correct that. */
8667 base_list = nreverse (base_list);
8670 pop_scope (pushed_scope);
8672 /* Now call xref_basetypes to set up all the base-class
8674 xref_basetypes (type, base_list);
8676 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8677 (int) ATTR_FLAG_TYPE_IN_PLACE,
8678 args, tf_error, NULL_TREE);
8679 fixup_attribute_variants (type);
8681 /* Now that our base classes are set up, enter the scope of the
8682 class, so that name lookups into base classes, etc. will work
8683 correctly. This is precisely analogous to what we do in
8684 begin_class_definition when defining an ordinary non-template
8685 class, except we also need to push the enclosing classes. */
8686 push_nested_class (type);
8688 /* Now members are processed in the order of declaration. */
8689 for (member = CLASSTYPE_DECL_LIST (pattern);
8690 member; member = TREE_CHAIN (member))
8692 tree t = TREE_VALUE (member);
8694 if (TREE_PURPOSE (member))
8698 /* Build new CLASSTYPE_NESTED_UTDS. */
8701 bool class_template_p;
8703 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8704 && TYPE_LANG_SPECIFIC (t)
8705 && CLASSTYPE_IS_TEMPLATE (t));
8706 /* If the member is a class template, then -- even after
8707 substitution -- there may be dependent types in the
8708 template argument list for the class. We increment
8709 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8710 that function will assume that no types are dependent
8711 when outside of a template. */
8712 if (class_template_p)
8713 ++processing_template_decl;
8714 newtag = tsubst (t, args, tf_error, NULL_TREE);
8715 if (class_template_p)
8716 --processing_template_decl;
8717 if (newtag == error_mark_node)
8720 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8722 tree name = TYPE_IDENTIFIER (t);
8724 if (class_template_p)
8725 /* Unfortunately, lookup_template_class sets
8726 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8727 instantiation (i.e., for the type of a member
8728 template class nested within a template class.)
8729 This behavior is required for
8730 maybe_process_partial_specialization to work
8731 correctly, but is not accurate in this case;
8732 the TAG is not an instantiation of anything.
8733 (The corresponding TEMPLATE_DECL is an
8734 instantiation, but the TYPE is not.) */
8735 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8737 /* Now, we call pushtag to put this NEWTAG into the scope of
8738 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8739 pushtag calling push_template_decl. We don't have to do
8740 this for enums because it will already have been done in
8743 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8744 pushtag (name, newtag, /*tag_scope=*/ts_current);
8747 else if (TREE_CODE (t) == FUNCTION_DECL
8748 || DECL_FUNCTION_TEMPLATE_P (t))
8750 /* Build new TYPE_METHODS. */
8753 if (TREE_CODE (t) == TEMPLATE_DECL)
8754 ++processing_template_decl;
8755 r = tsubst (t, args, tf_error, NULL_TREE);
8756 if (TREE_CODE (t) == TEMPLATE_DECL)
8757 --processing_template_decl;
8758 set_current_access_from_decl (r);
8759 finish_member_declaration (r);
8760 /* Instantiate members marked with attribute used. */
8761 if (r != error_mark_node && DECL_PRESERVE_P (r))
8766 /* Build new TYPE_FIELDS. */
8767 if (TREE_CODE (t) == STATIC_ASSERT)
8770 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8771 tf_warning_or_error, NULL_TREE,
8772 /*integral_constant_expression_p=*/true);
8773 finish_static_assert (condition,
8774 STATIC_ASSERT_MESSAGE (t),
8775 STATIC_ASSERT_SOURCE_LOCATION (t),
8778 else if (TREE_CODE (t) != CONST_DECL)
8782 /* The file and line for this declaration, to
8783 assist in error message reporting. Since we
8784 called push_tinst_level above, we don't need to
8786 input_location = DECL_SOURCE_LOCATION (t);
8788 if (TREE_CODE (t) == TEMPLATE_DECL)
8789 ++processing_template_decl;
8790 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8791 if (TREE_CODE (t) == TEMPLATE_DECL)
8792 --processing_template_decl;
8793 if (TREE_CODE (r) == VAR_DECL)
8797 [t]he initialization (and any associated
8798 side-effects) of a static data member does
8799 not occur unless the static data member is
8800 itself used in a way that requires the
8801 definition of the static data member to
8804 Therefore, we do not substitute into the
8805 initialized for the static data member here. */
8806 finish_static_data_member_decl
8809 /*init_const_expr_p=*/false,
8810 /*asmspec_tree=*/NULL_TREE,
8812 /* Instantiate members marked with attribute used. */
8813 if (r != error_mark_node && DECL_PRESERVE_P (r))
8816 else if (TREE_CODE (r) == FIELD_DECL)
8818 /* Determine whether R has a valid type and can be
8819 completed later. If R is invalid, then it is
8820 replaced by error_mark_node so that it will not be
8821 added to TYPE_FIELDS. */
8822 tree rtype = TREE_TYPE (r);
8823 if (can_complete_type_without_circularity (rtype))
8824 complete_type (rtype);
8826 if (!COMPLETE_TYPE_P (rtype))
8828 cxx_incomplete_type_error (r, rtype);
8829 r = error_mark_node;
8833 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8834 such a thing will already have been added to the field
8835 list by tsubst_enum in finish_member_declaration in the
8836 CLASSTYPE_NESTED_UTDS case above. */
8837 if (!(TREE_CODE (r) == TYPE_DECL
8838 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8839 && DECL_ARTIFICIAL (r)))
8841 set_current_access_from_decl (r);
8842 finish_member_declaration (r);
8849 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
8851 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8853 tree friend_type = t;
8854 bool adjust_processing_template_decl = false;
8856 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8858 /* template <class T> friend class C; */
8859 friend_type = tsubst_friend_class (friend_type, args);
8860 adjust_processing_template_decl = true;
8862 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8864 /* template <class T> friend class C::D; */
8865 friend_type = tsubst (friend_type, args,
8866 tf_warning_or_error, NULL_TREE);
8867 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8868 friend_type = TREE_TYPE (friend_type);
8869 adjust_processing_template_decl = true;
8871 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8872 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8874 /* This could be either
8878 when dependent_type_p is false or
8880 template <class U> friend class T::C;
8883 friend_type = tsubst (friend_type, args,
8884 tf_warning_or_error, NULL_TREE);
8885 /* Bump processing_template_decl for correct
8886 dependent_type_p calculation. */
8887 ++processing_template_decl;
8888 if (dependent_type_p (friend_type))
8889 adjust_processing_template_decl = true;
8890 --processing_template_decl;
8892 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8893 && hidden_name_p (TYPE_NAME (friend_type)))
8897 where C hasn't been declared yet. Let's lookup name
8898 from namespace scope directly, bypassing any name that
8899 come from dependent base class. */
8900 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8902 /* The call to xref_tag_from_type does injection for friend
8904 push_nested_namespace (ns);
8906 xref_tag_from_type (friend_type, NULL_TREE,
8907 /*tag_scope=*/ts_current);
8908 pop_nested_namespace (ns);
8910 else if (uses_template_parms (friend_type))
8911 /* friend class C<T>; */
8912 friend_type = tsubst (friend_type, args,
8913 tf_warning_or_error, NULL_TREE);
8918 where C is already declared or
8920 friend class C<int>;
8922 We don't have to do anything in these cases. */
8924 if (adjust_processing_template_decl)
8925 /* Trick make_friend_class into realizing that the friend
8926 we're adding is a template, not an ordinary class. It's
8927 important that we use make_friend_class since it will
8928 perform some error-checking and output cross-reference
8930 ++processing_template_decl;
8932 if (friend_type != error_mark_node)
8933 make_friend_class (type, friend_type, /*complain=*/false);
8935 if (adjust_processing_template_decl)
8936 --processing_template_decl;
8940 /* Build new DECL_FRIENDLIST. */
8943 /* The file and line for this declaration, to
8944 assist in error message reporting. Since we
8945 called push_tinst_level above, we don't need to
8947 input_location = DECL_SOURCE_LOCATION (t);
8949 if (TREE_CODE (t) == TEMPLATE_DECL)
8951 ++processing_template_decl;
8952 push_deferring_access_checks (dk_no_check);
8955 r = tsubst_friend_function (t, args);
8956 add_friend (type, r, /*complain=*/false);
8957 if (TREE_CODE (t) == TEMPLATE_DECL)
8959 pop_deferring_access_checks ();
8960 --processing_template_decl;
8966 if (CLASSTYPE_LAMBDA_EXPR (type))
8968 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
8969 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
8971 apply_lambda_return_type (lambda, void_type_node);
8972 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
8974 instantiate_decl (lambda_function (type), false, false);
8975 maybe_add_lambda_conv_op (type);
8978 /* Set the file and line number information to whatever is given for
8979 the class itself. This puts error messages involving generated
8980 implicit functions at a predictable point, and the same point
8981 that would be used for non-template classes. */
8982 input_location = DECL_SOURCE_LOCATION (typedecl);
8984 unreverse_member_declarations (type);
8985 finish_struct_1 (type);
8986 TYPE_BEING_DEFINED (type) = 0;
8988 /* We don't instantiate default arguments for member functions. 14.7.1:
8990 The implicit instantiation of a class template specialization causes
8991 the implicit instantiation of the declarations, but not of the
8992 definitions or default arguments, of the class member functions,
8993 member classes, static data members and member templates.... */
8995 /* Some typedefs referenced from within the template code need to be access
8996 checked at template instantiation time, i.e now. These types were
8997 added to the template at parsing time. Let's get those and perform
8998 the access checks then. */
8999 perform_typedefs_access_check (pattern, args);
9000 perform_deferred_access_checks ();
9001 pop_nested_class ();
9002 maximum_field_alignment = saved_maximum_field_alignment;
9003 pop_from_top_level ();
9004 pop_deferring_access_checks ();
9007 /* The vtable for a template class can be emitted in any translation
9008 unit in which the class is instantiated. When there is no key
9009 method, however, finish_struct_1 will already have added TYPE to
9010 the keyed_classes list. */
9011 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9012 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9017 /* Wrapper for instantiate_class_template_1. */
9020 instantiate_class_template (tree type)
9023 timevar_push (TV_TEMPLATE_INST);
9024 ret = instantiate_class_template_1 (type);
9025 timevar_pop (TV_TEMPLATE_INST);
9030 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9036 else if (TYPE_P (t))
9037 r = tsubst (t, args, complain, in_decl);
9040 if (!(complain & tf_warning))
9041 ++c_inhibit_evaluation_warnings;
9042 r = tsubst_expr (t, args, complain, in_decl,
9043 /*integral_constant_expression_p=*/true);
9044 if (!(complain & tf_warning))
9045 --c_inhibit_evaluation_warnings;
9046 /* Preserve the raw-reference nature of T. */
9047 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9048 && REFERENCE_REF_P (r))
9049 r = TREE_OPERAND (r, 0);
9054 /* Given a function parameter pack TMPL_PARM and some function parameters
9055 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9056 and set *SPEC_P to point at the next point in the list. */
9059 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9061 /* Collect all of the extra "packed" parameters into an
9065 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9066 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9067 tree spec_parm = *spec_p;
9070 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9072 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9075 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9076 parmvec = make_tree_vec (len);
9077 parmtypevec = make_tree_vec (len);
9078 spec_parm = *spec_p;
9079 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9081 TREE_VEC_ELT (parmvec, i) = spec_parm;
9082 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9085 /* Build the argument packs. */
9086 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9087 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9088 TREE_TYPE (argpack) = argtypepack;
9089 *spec_p = spec_parm;
9094 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9095 NONTYPE_ARGUMENT_PACK. */
9098 make_fnparm_pack (tree spec_parm)
9100 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9103 /* Substitute ARGS into T, which is an pack expansion
9104 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9105 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9106 (if only a partial substitution could be performed) or
9107 ERROR_MARK_NODE if there was an error. */
9109 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9113 tree pack, packs = NULL_TREE;
9114 bool unsubstituted_packs = false;
9117 htab_t saved_local_specializations = NULL;
9119 gcc_assert (PACK_EXPANSION_P (t));
9120 pattern = PACK_EXPANSION_PATTERN (t);
9122 /* Determine the argument packs that will instantiate the parameter
9123 packs used in the expansion expression. While we're at it,
9124 compute the number of arguments to be expanded and make sure it
9126 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9127 pack = TREE_CHAIN (pack))
9129 tree parm_pack = TREE_VALUE (pack);
9130 tree arg_pack = NULL_TREE;
9131 tree orig_arg = NULL_TREE;
9133 if (TREE_CODE (parm_pack) == BASES)
9135 if (BASES_DIRECT (parm_pack))
9136 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9137 args, complain, in_decl, false));
9139 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9140 args, complain, in_decl, false));
9142 if (TREE_CODE (parm_pack) == PARM_DECL)
9144 if (!cp_unevaluated_operand)
9145 arg_pack = retrieve_local_specialization (parm_pack);
9148 /* We can't rely on local_specializations for a parameter
9149 name used later in a function declaration (such as in a
9150 late-specified return type). Even if it exists, it might
9151 have the wrong value for a recursive call. Just make a
9152 dummy decl, since it's only used for its type. */
9153 arg_pack = tsubst_decl (parm_pack, args, complain);
9154 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9155 /* Partial instantiation of the parm_pack, we can't build
9156 up an argument pack yet. */
9157 arg_pack = NULL_TREE;
9159 arg_pack = make_fnparm_pack (arg_pack);
9164 int level, idx, levels;
9165 template_parm_level_and_index (parm_pack, &level, &idx);
9167 levels = TMPL_ARGS_DEPTH (args);
9168 if (level <= levels)
9169 arg_pack = TMPL_ARG (args, level, idx);
9172 orig_arg = arg_pack;
9173 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9174 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9176 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9177 /* This can only happen if we forget to expand an argument
9178 pack somewhere else. Just return an error, silently. */
9180 result = make_tree_vec (1);
9181 TREE_VEC_ELT (result, 0) = error_mark_node;
9185 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9186 /* The argument pack that the parameter maps to is just an
9187 expansion of the parameter itself, such as one would find
9188 in the implicit typedef of a class inside the class itself.
9189 Consider this parameter "unsubstituted", so that we will
9190 maintain the outer pack expansion. */
9191 arg_pack = NULL_TREE;
9196 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9198 /* Don't bother trying to do a partial substitution with
9199 incomplete packs; we'll try again after deduction. */
9200 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9205 else if (len != my_len)
9207 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9208 error ("mismatched argument pack lengths while expanding "
9212 error ("mismatched argument pack lengths while expanding "
9215 return error_mark_node;
9218 /* Keep track of the parameter packs and their corresponding
9220 packs = tree_cons (parm_pack, arg_pack, packs);
9221 TREE_TYPE (packs) = orig_arg;
9225 /* We can't substitute for this parameter pack. */
9226 unsubstituted_packs = true;
9231 /* We cannot expand this expansion expression, because we don't have
9232 all of the argument packs we need. Substitute into the pattern
9233 and return a PACK_EXPANSION_*. The caller will need to deal with
9235 if (unsubstituted_packs)
9238 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9239 new_pat = tsubst_expr (pattern, args, complain, in_decl,
9240 /*integral_constant_expression_p=*/false);
9242 new_pat = tsubst (pattern, args, complain, in_decl);
9243 return make_pack_expansion (new_pat);
9246 /* We could not find any argument packs that work. */
9248 return error_mark_node;
9250 if (cp_unevaluated_operand)
9252 /* We're in a late-specified return type, so create our own local
9253 specializations table; the current table is either NULL or (in the
9254 case of recursive unification) might have bindings that we don't
9255 want to use or alter. */
9256 saved_local_specializations = local_specializations;
9257 local_specializations = htab_create (37,
9258 hash_local_specialization,
9259 eq_local_specializations,
9263 /* For each argument in each argument pack, substitute into the
9265 result = make_tree_vec (len);
9266 for (i = 0; i < len; ++i)
9268 /* For parameter pack, change the substitution of the parameter
9269 pack to the ith argument in its argument pack, then expand
9271 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9273 tree parm = TREE_PURPOSE (pack);
9276 /* Select the Ith argument from the pack. */
9277 if (TREE_CODE (parm) == PARM_DECL)
9281 arg = make_node (ARGUMENT_PACK_SELECT);
9282 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9284 register_local_specialization (arg, parm);
9287 arg = retrieve_local_specialization (parm);
9292 template_parm_level_and_index (parm, &level, &idx);
9296 arg = make_node (ARGUMENT_PACK_SELECT);
9297 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9298 /* Update the corresponding argument. */
9299 TMPL_ARG (args, level, idx) = arg;
9302 /* Re-use the ARGUMENT_PACK_SELECT. */
9303 arg = TMPL_ARG (args, level, idx);
9305 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9308 /* Substitute into the PATTERN with the altered arguments. */
9309 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9310 TREE_VEC_ELT (result, i) =
9311 tsubst_expr (pattern, args, complain, in_decl,
9312 /*integral_constant_expression_p=*/false);
9314 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9316 if (TREE_VEC_ELT (result, i) == error_mark_node)
9318 result = error_mark_node;
9323 /* Update ARGS to restore the substitution from parameter packs to
9324 their argument packs. */
9325 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9327 tree parm = TREE_PURPOSE (pack);
9329 if (TREE_CODE (parm) == PARM_DECL)
9330 register_local_specialization (TREE_TYPE (pack), parm);
9334 template_parm_level_and_index (parm, &level, &idx);
9336 /* Update the corresponding argument. */
9337 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9338 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9341 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9345 if (saved_local_specializations)
9347 htab_delete (local_specializations);
9348 local_specializations = saved_local_specializations;
9354 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9355 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9356 parameter packs; all parms generated from a function parameter pack will
9357 have the same DECL_PARM_INDEX. */
9360 get_pattern_parm (tree parm, tree tmpl)
9362 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9365 if (DECL_ARTIFICIAL (parm))
9367 for (patparm = DECL_ARGUMENTS (pattern);
9368 patparm; patparm = DECL_CHAIN (patparm))
9369 if (DECL_ARTIFICIAL (patparm)
9370 && DECL_NAME (parm) == DECL_NAME (patparm))
9375 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9376 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9377 gcc_assert (DECL_PARM_INDEX (patparm)
9378 == DECL_PARM_INDEX (parm));
9384 /* Substitute ARGS into the vector or list of template arguments T. */
9387 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9390 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9393 if (t == error_mark_node)
9394 return error_mark_node;
9396 len = TREE_VEC_LENGTH (t);
9397 elts = XALLOCAVEC (tree, len);
9399 for (i = 0; i < len; i++)
9401 tree orig_arg = TREE_VEC_ELT (t, i);
9404 if (TREE_CODE (orig_arg) == TREE_VEC)
9405 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9406 else if (PACK_EXPANSION_P (orig_arg))
9408 /* Substitute into an expansion expression. */
9409 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9411 if (TREE_CODE (new_arg) == TREE_VEC)
9412 /* Add to the expanded length adjustment the number of
9413 expanded arguments. We subtract one from this
9414 measurement, because the argument pack expression
9415 itself is already counted as 1 in
9416 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9417 the argument pack is empty. */
9418 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9420 else if (ARGUMENT_PACK_P (orig_arg))
9422 /* Substitute into each of the arguments. */
9423 new_arg = TYPE_P (orig_arg)
9424 ? cxx_make_type (TREE_CODE (orig_arg))
9425 : make_node (TREE_CODE (orig_arg));
9427 SET_ARGUMENT_PACK_ARGS (
9429 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9430 args, complain, in_decl));
9432 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9433 new_arg = error_mark_node;
9435 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9436 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9438 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9440 if (TREE_TYPE (new_arg) == error_mark_node)
9441 new_arg = error_mark_node;
9445 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9447 if (new_arg == error_mark_node)
9448 return error_mark_node;
9451 if (new_arg != orig_arg)
9458 /* Make space for the expanded arguments coming from template
9460 t = make_tree_vec (len + expanded_len_adjust);
9461 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9462 arguments for a member template.
9463 In that case each TREE_VEC in ORIG_T represents a level of template
9464 arguments, and ORIG_T won't carry any non defaulted argument count.
9465 It will rather be the nested TREE_VECs that will carry one.
9466 In other words, ORIG_T carries a non defaulted argument count only
9467 if it doesn't contain any nested TREE_VEC. */
9468 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9470 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9471 count += expanded_len_adjust;
9472 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9474 for (i = 0, out = 0; i < len; i++)
9476 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9477 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9478 && TREE_CODE (elts[i]) == TREE_VEC)
9482 /* Now expand the template argument pack "in place". */
9483 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9484 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9488 TREE_VEC_ELT (t, out) = elts[i];
9496 /* Return the result of substituting ARGS into the template parameters
9497 given by PARMS. If there are m levels of ARGS and m + n levels of
9498 PARMS, then the result will contain n levels of PARMS. For
9499 example, if PARMS is `template <class T> template <class U>
9500 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9501 result will be `template <int*, double, class V>'. */
9504 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9509 /* When substituting into a template, we must set
9510 PROCESSING_TEMPLATE_DECL as the template parameters may be
9511 dependent if they are based on one-another, and the dependency
9512 predicates are short-circuit outside of templates. */
9513 ++processing_template_decl;
9515 for (new_parms = &r;
9516 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9517 new_parms = &(TREE_CHAIN (*new_parms)),
9518 parms = TREE_CHAIN (parms))
9521 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9524 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9528 if (parms == error_mark_node)
9531 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9533 if (tuple == error_mark_node)
9536 TREE_VEC_ELT (new_vec, i) =
9537 tsubst_template_parm (tuple, args, complain);
9541 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9542 - TMPL_ARGS_DEPTH (args)),
9543 new_vec, NULL_TREE);
9546 --processing_template_decl;
9551 /* Return the result of substituting ARGS into one template parameter
9552 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9553 parameter and which TREE_PURPOSE is the default argument of the
9554 template parameter. */
9557 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9559 tree default_value, parm_decl;
9561 if (args == NULL_TREE
9563 || t == error_mark_node)
9566 gcc_assert (TREE_CODE (t) == TREE_LIST);
9568 default_value = TREE_PURPOSE (t);
9569 parm_decl = TREE_VALUE (t);
9571 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9572 if (TREE_CODE (parm_decl) == PARM_DECL
9573 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9574 parm_decl = error_mark_node;
9575 default_value = tsubst_template_arg (default_value, args,
9576 complain, NULL_TREE);
9578 return build_tree_list (default_value, parm_decl);
9581 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9582 type T. If T is not an aggregate or enumeration type, it is
9583 handled as if by tsubst. IN_DECL is as for tsubst. If
9584 ENTERING_SCOPE is nonzero, T is the context for a template which
9585 we are presently tsubst'ing. Return the substituted value. */
9588 tsubst_aggr_type (tree t,
9590 tsubst_flags_t complain,
9597 switch (TREE_CODE (t))
9600 if (TYPE_PTRMEMFUNC_P (t))
9601 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9603 /* Else fall through. */
9606 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9611 int saved_unevaluated_operand;
9612 int saved_inhibit_evaluation_warnings;
9614 /* In "sizeof(X<I>)" we need to evaluate "I". */
9615 saved_unevaluated_operand = cp_unevaluated_operand;
9616 cp_unevaluated_operand = 0;
9617 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9618 c_inhibit_evaluation_warnings = 0;
9620 /* First, determine the context for the type we are looking
9622 context = TYPE_CONTEXT (t);
9623 if (context && TYPE_P (context))
9625 context = tsubst_aggr_type (context, args, complain,
9626 in_decl, /*entering_scope=*/1);
9627 /* If context is a nested class inside a class template,
9628 it may still need to be instantiated (c++/33959). */
9629 context = complete_type (context);
9632 /* Then, figure out what arguments are appropriate for the
9633 type we are trying to find. For example, given:
9635 template <class T> struct S;
9636 template <class T, class U> void f(T, U) { S<U> su; }
9638 and supposing that we are instantiating f<int, double>,
9639 then our ARGS will be {int, double}, but, when looking up
9640 S we only want {double}. */
9641 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9643 if (argvec == error_mark_node)
9644 r = error_mark_node;
9647 r = lookup_template_class (t, argvec, in_decl, context,
9648 entering_scope, complain);
9649 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9652 cp_unevaluated_operand = saved_unevaluated_operand;
9653 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9658 /* This is not a template type, so there's nothing to do. */
9662 return tsubst (t, args, complain, in_decl);
9666 /* Substitute into the default argument ARG (a default argument for
9667 FN), which has the indicated TYPE. */
9670 tsubst_default_argument (tree fn, tree type, tree arg)
9672 tree saved_class_ptr = NULL_TREE;
9673 tree saved_class_ref = NULL_TREE;
9675 /* This can happen in invalid code. */
9676 if (TREE_CODE (arg) == DEFAULT_ARG)
9679 /* This default argument came from a template. Instantiate the
9680 default argument here, not in tsubst. In the case of
9689 we must be careful to do name lookup in the scope of S<T>,
9690 rather than in the current class. */
9691 push_access_scope (fn);
9692 /* The "this" pointer is not valid in a default argument. */
9695 saved_class_ptr = current_class_ptr;
9696 cp_function_chain->x_current_class_ptr = NULL_TREE;
9697 saved_class_ref = current_class_ref;
9698 cp_function_chain->x_current_class_ref = NULL_TREE;
9701 push_deferring_access_checks(dk_no_deferred);
9702 /* The default argument expression may cause implicitly defined
9703 member functions to be synthesized, which will result in garbage
9704 collection. We must treat this situation as if we were within
9705 the body of function so as to avoid collecting live data on the
9708 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9709 tf_warning_or_error, NULL_TREE,
9710 /*integral_constant_expression_p=*/false);
9712 pop_deferring_access_checks();
9714 /* Restore the "this" pointer. */
9717 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9718 cp_function_chain->x_current_class_ref = saved_class_ref;
9721 /* Make sure the default argument is reasonable. */
9722 arg = check_default_argument (type, arg);
9724 pop_access_scope (fn);
9729 /* Substitute into all the default arguments for FN. */
9732 tsubst_default_arguments (tree fn)
9737 tmpl_args = DECL_TI_ARGS (fn);
9739 /* If this function is not yet instantiated, we certainly don't need
9740 its default arguments. */
9741 if (uses_template_parms (tmpl_args))
9743 /* Don't do this again for clones. */
9744 if (DECL_CLONED_FUNCTION_P (fn))
9747 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9749 arg = TREE_CHAIN (arg))
9750 if (TREE_PURPOSE (arg))
9751 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9753 TREE_PURPOSE (arg));
9756 /* Substitute the ARGS into the T, which is a _DECL. Return the
9757 result of the substitution. Issue error and warning messages under
9758 control of COMPLAIN. */
9761 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9763 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9764 location_t saved_loc;
9769 /* Set the filename and linenumber to improve error-reporting. */
9770 saved_loc = input_location;
9771 input_location = DECL_SOURCE_LOCATION (t);
9773 switch (TREE_CODE (t))
9777 /* We can get here when processing a member function template,
9778 member class template, or template template parameter. */
9779 tree decl = DECL_TEMPLATE_RESULT (t);
9784 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9786 /* Template template parameter is treated here. */
9787 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9788 if (new_type == error_mark_node)
9789 RETURN (error_mark_node);
9792 DECL_CHAIN (r) = NULL_TREE;
9793 TREE_TYPE (r) = new_type;
9794 DECL_TEMPLATE_RESULT (r)
9795 = build_decl (DECL_SOURCE_LOCATION (decl),
9796 TYPE_DECL, DECL_NAME (decl), new_type);
9797 DECL_TEMPLATE_PARMS (r)
9798 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9800 TYPE_NAME (new_type) = r;
9804 /* We might already have an instance of this template.
9805 The ARGS are for the surrounding class type, so the
9806 full args contain the tsubst'd args for the context,
9807 plus the innermost args from the template decl. */
9808 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
9809 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
9810 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
9811 /* Because this is a template, the arguments will still be
9812 dependent, even after substitution. If
9813 PROCESSING_TEMPLATE_DECL is not set, the dependency
9814 predicates will short-circuit. */
9815 ++processing_template_decl;
9816 full_args = tsubst_template_args (tmpl_args, args,
9818 --processing_template_decl;
9819 if (full_args == error_mark_node)
9820 RETURN (error_mark_node);
9822 /* If this is a default template template argument,
9823 tsubst might not have changed anything. */
9824 if (full_args == tmpl_args)
9827 hash = hash_tmpl_and_args (t, full_args);
9828 spec = retrieve_specialization (t, full_args, hash);
9829 if (spec != NULL_TREE)
9835 /* Make a new template decl. It will be similar to the
9836 original, but will record the current template arguments.
9837 We also create a new function declaration, which is just
9838 like the old one, but points to this new template, rather
9839 than the old one. */
9841 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
9842 DECL_CHAIN (r) = NULL_TREE;
9844 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
9846 if (TREE_CODE (decl) == TYPE_DECL)
9849 ++processing_template_decl;
9850 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9851 --processing_template_decl;
9852 if (new_type == error_mark_node)
9853 RETURN (error_mark_node);
9855 TREE_TYPE (r) = new_type;
9856 CLASSTYPE_TI_TEMPLATE (new_type) = r;
9857 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
9858 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
9859 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
9864 ++processing_template_decl;
9865 new_decl = tsubst (decl, args, complain, in_decl);
9866 --processing_template_decl;
9867 if (new_decl == error_mark_node)
9868 RETURN (error_mark_node);
9870 DECL_TEMPLATE_RESULT (r) = new_decl;
9871 DECL_TI_TEMPLATE (new_decl) = r;
9872 TREE_TYPE (r) = TREE_TYPE (new_decl);
9873 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
9874 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
9877 SET_DECL_IMPLICIT_INSTANTIATION (r);
9878 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
9879 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
9881 /* The template parameters for this new template are all the
9882 template parameters for the old template, except the
9883 outermost level of parameters. */
9884 DECL_TEMPLATE_PARMS (r)
9885 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
9888 if (PRIMARY_TEMPLATE_P (t))
9889 DECL_PRIMARY_TEMPLATE (r) = r;
9891 if (TREE_CODE (decl) != TYPE_DECL)
9892 /* Record this non-type partial instantiation. */
9893 register_specialization (r, t,
9894 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
9902 tree argvec = NULL_TREE;
9910 /* Nobody should be tsubst'ing into non-template functions. */
9911 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
9913 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
9918 /* If T is not dependent, just return it. We have to
9919 increment PROCESSING_TEMPLATE_DECL because
9920 value_dependent_expression_p assumes that nothing is
9921 dependent when PROCESSING_TEMPLATE_DECL is zero. */
9922 ++processing_template_decl;
9923 dependent_p = value_dependent_expression_p (t);
9924 --processing_template_decl;
9928 /* Calculate the most general template of which R is a
9929 specialization, and the complete set of arguments used to
9931 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
9932 argvec = tsubst_template_args (DECL_TI_ARGS
9933 (DECL_TEMPLATE_RESULT
9934 (DECL_TI_TEMPLATE (t))),
9935 args, complain, in_decl);
9936 if (argvec == error_mark_node)
9937 RETURN (error_mark_node);
9939 /* Check to see if we already have this specialization. */
9940 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9941 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9949 /* We can see more levels of arguments than parameters if
9950 there was a specialization of a member template, like
9953 template <class T> struct S { template <class U> void f(); }
9954 template <> template <class U> void S<int>::f(U);
9956 Here, we'll be substituting into the specialization,
9957 because that's where we can find the code we actually
9958 want to generate, but we'll have enough arguments for
9959 the most general template.
9961 We also deal with the peculiar case:
9963 template <class T> struct S {
9964 template <class U> friend void f();
9966 template <class U> void f() {}
9968 template void f<double>();
9970 Here, the ARGS for the instantiation of will be {int,
9971 double}. But, we only need as many ARGS as there are
9972 levels of template parameters in CODE_PATTERN. We are
9973 careful not to get fooled into reducing the ARGS in
9976 template <class T> struct S { template <class U> void f(U); }
9977 template <class T> template <> void S<T>::f(int) {}
9979 which we can spot because the pattern will be a
9980 specialization in this case. */
9981 args_depth = TMPL_ARGS_DEPTH (args);
9983 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9984 if (args_depth > parms_depth
9985 && !DECL_TEMPLATE_SPECIALIZATION (t))
9986 args = get_innermost_template_args (args, parms_depth);
9990 /* This special case arises when we have something like this:
9992 template <class T> struct S {
9993 friend void f<int>(int, double);
9996 Here, the DECL_TI_TEMPLATE for the friend declaration
9997 will be an IDENTIFIER_NODE. We are being called from
9998 tsubst_friend_function, and we want only to create a
9999 new decl (R) with appropriate types so that we can call
10000 determine_specialization. */
10001 gen_tmpl = NULL_TREE;
10004 if (DECL_CLASS_SCOPE_P (t))
10006 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10010 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10011 complain, t, /*entering_scope=*/1);
10016 ctx = DECL_CONTEXT (t);
10018 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10019 if (type == error_mark_node)
10020 RETURN (error_mark_node);
10022 /* We do NOT check for matching decls pushed separately at this
10023 point, as they may not represent instantiations of this
10024 template, and in any case are considered separate under the
10027 DECL_USE_TEMPLATE (r) = 0;
10028 TREE_TYPE (r) = type;
10029 /* Clear out the mangled name and RTL for the instantiation. */
10030 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10031 SET_DECL_RTL (r, NULL);
10032 /* Leave DECL_INITIAL set on deleted instantiations. */
10033 if (!DECL_DELETED_FN (r))
10034 DECL_INITIAL (r) = NULL_TREE;
10035 DECL_CONTEXT (r) = ctx;
10037 if (member && DECL_CONV_FN_P (r))
10038 /* Type-conversion operator. Reconstruct the name, in
10039 case it's the name of one of the template's parameters. */
10040 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10042 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10044 DECL_RESULT (r) = NULL_TREE;
10046 TREE_STATIC (r) = 0;
10047 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10048 DECL_EXTERNAL (r) = 1;
10049 /* If this is an instantiation of a function with internal
10050 linkage, we already know what object file linkage will be
10051 assigned to the instantiation. */
10052 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10053 DECL_DEFER_OUTPUT (r) = 0;
10054 DECL_CHAIN (r) = NULL_TREE;
10055 DECL_PENDING_INLINE_INFO (r) = 0;
10056 DECL_PENDING_INLINE_P (r) = 0;
10057 DECL_SAVED_TREE (r) = NULL_TREE;
10058 DECL_STRUCT_FUNCTION (r) = NULL;
10060 /* We'll re-clone as appropriate in instantiate_template. */
10061 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10063 /* If we aren't complaining now, return on error before we register
10064 the specialization so that we'll complain eventually. */
10065 if ((complain & tf_error) == 0
10066 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10067 && !grok_op_properties (r, /*complain=*/false))
10068 RETURN (error_mark_node);
10070 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10071 this in the special friend case mentioned above where
10072 GEN_TMPL is NULL. */
10075 DECL_TEMPLATE_INFO (r)
10076 = build_template_info (gen_tmpl, argvec);
10077 SET_DECL_IMPLICIT_INSTANTIATION (r);
10078 register_specialization (r, gen_tmpl, argvec, false, hash);
10080 /* We're not supposed to instantiate default arguments
10081 until they are called, for a template. But, for a
10084 template <class T> void f ()
10085 { extern void g(int i = T()); }
10087 we should do the substitution when the template is
10088 instantiated. We handle the member function case in
10089 instantiate_class_template since the default arguments
10090 might refer to other members of the class. */
10092 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10093 && !uses_template_parms (argvec))
10094 tsubst_default_arguments (r);
10097 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10099 /* Copy the list of befriending classes. */
10100 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10102 friends = &TREE_CHAIN (*friends))
10104 *friends = copy_node (*friends);
10105 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10110 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10112 maybe_retrofit_in_chrg (r);
10113 if (DECL_CONSTRUCTOR_P (r))
10114 grok_ctor_properties (ctx, r);
10115 /* If this is an instantiation of a member template, clone it.
10116 If it isn't, that'll be handled by
10117 clone_constructors_and_destructors. */
10118 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10119 clone_function_decl (r, /*update_method_vec_p=*/0);
10121 else if ((complain & tf_error) != 0
10122 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10123 && !grok_op_properties (r, /*complain=*/true))
10124 RETURN (error_mark_node);
10126 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10127 SET_DECL_FRIEND_CONTEXT (r,
10128 tsubst (DECL_FRIEND_CONTEXT (t),
10129 args, complain, in_decl));
10131 /* Possibly limit visibility based on template args. */
10132 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10133 if (DECL_VISIBILITY_SPECIFIED (t))
10135 DECL_VISIBILITY_SPECIFIED (r) = 0;
10136 DECL_ATTRIBUTES (r)
10137 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10139 determine_visibility (r);
10140 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10141 && !processing_template_decl)
10142 defaulted_late_check (r);
10144 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10145 args, complain, in_decl);
10151 tree type = NULL_TREE;
10153 tree expanded_types = NULL_TREE;
10154 tree prev_r = NULL_TREE;
10155 tree first_r = NULL_TREE;
10157 if (FUNCTION_PARAMETER_PACK_P (t))
10159 /* If there is a local specialization that isn't a
10160 parameter pack, it means that we're doing a "simple"
10161 substitution from inside tsubst_pack_expansion. Just
10162 return the local specialization (which will be a single
10164 tree spec = retrieve_local_specialization (t);
10166 && TREE_CODE (spec) == PARM_DECL
10167 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10170 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10171 the parameters in this function parameter pack. */
10172 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10173 complain, in_decl);
10174 if (TREE_CODE (expanded_types) == TREE_VEC)
10176 len = TREE_VEC_LENGTH (expanded_types);
10178 /* Zero-length parameter packs are boring. Just substitute
10181 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10186 /* All we did was update the type. Make a note of that. */
10187 type = expanded_types;
10188 expanded_types = NULL_TREE;
10192 /* Loop through all of the parameter's we'll build. When T is
10193 a function parameter pack, LEN is the number of expanded
10194 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10196 for (i = 0; i < len; ++i)
10200 if (DECL_TEMPLATE_PARM_P (t))
10201 SET_DECL_TEMPLATE_PARM_P (r);
10203 if (expanded_types)
10204 /* We're on the Ith parameter of the function parameter
10207 /* An argument of a function parameter pack is not a parameter
10209 FUNCTION_PARAMETER_PACK_P (r) = false;
10211 /* Get the Ith type. */
10212 type = TREE_VEC_ELT (expanded_types, i);
10215 /* Rename the parameter to include the index. */
10217 make_ith_pack_parameter_name (DECL_NAME (r), i);
10220 /* We're dealing with a normal parameter. */
10221 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10223 type = type_decays_to (type);
10224 TREE_TYPE (r) = type;
10225 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10227 if (DECL_INITIAL (r))
10229 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10230 DECL_INITIAL (r) = TREE_TYPE (r);
10232 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10233 complain, in_decl);
10236 DECL_CONTEXT (r) = NULL_TREE;
10238 if (!DECL_TEMPLATE_PARM_P (r))
10239 DECL_ARG_TYPE (r) = type_passed_as (type);
10241 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10242 args, complain, in_decl);
10244 /* Keep track of the first new parameter we
10245 generate. That's what will be returned to the
10250 /* Build a proper chain of parameters when substituting
10251 into a function parameter pack. */
10253 DECL_CHAIN (prev_r) = r;
10256 if (DECL_CHAIN (t))
10257 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10258 complain, DECL_CHAIN (t));
10260 /* FIRST_R contains the start of the chain we've built. */
10270 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10271 if (type == error_mark_node)
10272 RETURN (error_mark_node);
10273 TREE_TYPE (r) = type;
10274 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10276 if (DECL_C_BIT_FIELD (r))
10277 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10278 non-bit-fields DECL_INITIAL is a non-static data member
10279 initializer, which gets deferred instantiation. */
10281 = tsubst_expr (DECL_INITIAL (t), args,
10283 /*integral_constant_expression_p=*/true);
10284 else if (DECL_INITIAL (t))
10286 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10287 NSDMI in perform_member_init. Still set DECL_INITIAL
10288 so that we know there is one. */
10289 DECL_INITIAL (r) = void_zero_node;
10290 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10291 retrofit_lang_decl (r);
10292 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10294 /* We don't have to set DECL_CONTEXT here; it is set by
10295 finish_member_declaration. */
10296 DECL_CHAIN (r) = NULL_TREE;
10297 if (VOID_TYPE_P (type))
10298 error ("instantiation of %q+D as type %qT", r, type);
10300 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10301 args, complain, in_decl);
10306 /* We reach here only for member using decls. */
10307 if (DECL_DEPENDENT_P (t))
10309 r = do_class_using_decl
10310 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10311 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10313 r = error_mark_node;
10316 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10317 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10323 DECL_CHAIN (r) = NULL_TREE;
10330 tree argvec = NULL_TREE;
10331 tree gen_tmpl = NULL_TREE;
10333 tree tmpl = NULL_TREE;
10335 tree type = NULL_TREE;
10338 if (TREE_CODE (t) == TYPE_DECL
10339 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10341 /* If this is the canonical decl, we don't have to
10342 mess with instantiations, and often we can't (for
10343 typename, template type parms and such). Note that
10344 TYPE_NAME is not correct for the above test if
10345 we've copied the type for a typedef. */
10346 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10347 if (type == error_mark_node)
10348 RETURN (error_mark_node);
10349 r = TYPE_NAME (type);
10353 /* Check to see if we already have the specialization we
10356 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10358 /* T is a static data member or namespace-scope entity.
10359 We have to substitute into namespace-scope variables
10360 (even though such entities are never templates) because
10363 template <class T> void f() { extern T t; }
10365 where the entity referenced is not known until
10366 instantiation time. */
10368 ctx = DECL_CONTEXT (t);
10369 if (DECL_CLASS_SCOPE_P (t))
10371 ctx = tsubst_aggr_type (ctx, args,
10373 in_decl, /*entering_scope=*/1);
10374 /* If CTX is unchanged, then T is in fact the
10375 specialization we want. That situation occurs when
10376 referencing a static data member within in its own
10377 class. We can use pointer equality, rather than
10378 same_type_p, because DECL_CONTEXT is always
10380 if (ctx == DECL_CONTEXT (t))
10386 tmpl = DECL_TI_TEMPLATE (t);
10387 gen_tmpl = most_general_template (tmpl);
10388 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10389 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10390 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10395 /* A local variable. */
10397 /* Subsequent calls to pushdecl will fill this in. */
10399 spec = retrieve_local_specialization (t);
10401 /* If we already have the specialization we need, there is
10402 nothing more to do. */
10409 /* Create a new node for the specialization we need. */
10411 if (type == NULL_TREE)
10413 if (is_typedef_decl (t))
10414 type = DECL_ORIGINAL_TYPE (t);
10416 type = TREE_TYPE (t);
10417 if (TREE_CODE (t) == VAR_DECL && VAR_HAD_UNKNOWN_BOUND (t))
10418 type = strip_array_domain (type);
10419 type = tsubst (type, args, complain, in_decl);
10421 if (TREE_CODE (r) == VAR_DECL)
10423 /* Even if the original location is out of scope, the
10424 newly substituted one is not. */
10425 DECL_DEAD_FOR_LOCAL (r) = 0;
10426 DECL_INITIALIZED_P (r) = 0;
10427 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10428 if (type == error_mark_node)
10429 RETURN (error_mark_node);
10430 if (TREE_CODE (type) == FUNCTION_TYPE)
10432 /* It may seem that this case cannot occur, since:
10437 declares a function, not a variable. However:
10440 template <typename T> void g() { T t; }
10441 template void g<f>();
10443 is an attempt to declare a variable with function
10445 error ("variable %qD has function type",
10446 /* R is not yet sufficiently initialized, so we
10447 just use its name. */
10449 RETURN (error_mark_node);
10451 type = complete_type (type);
10452 /* Wait until cp_finish_decl to set this again, to handle
10453 circular dependency (template/instantiate6.C). */
10454 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10455 type = check_var_type (DECL_NAME (r), type);
10457 if (DECL_HAS_VALUE_EXPR_P (t))
10459 tree ve = DECL_VALUE_EXPR (t);
10460 ve = tsubst_expr (ve, args, complain, in_decl,
10461 /*constant_expression_p=*/false);
10462 if (REFERENCE_REF_P (ve))
10464 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10465 ve = TREE_OPERAND (ve, 0);
10467 SET_DECL_VALUE_EXPR (r, ve);
10470 else if (DECL_SELF_REFERENCE_P (t))
10471 SET_DECL_SELF_REFERENCE_P (r);
10472 TREE_TYPE (r) = type;
10473 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10474 DECL_CONTEXT (r) = ctx;
10475 /* Clear out the mangled name and RTL for the instantiation. */
10476 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10477 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10478 SET_DECL_RTL (r, NULL);
10479 /* The initializer must not be expanded until it is required;
10480 see [temp.inst]. */
10481 DECL_INITIAL (r) = NULL_TREE;
10482 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10483 SET_DECL_RTL (r, NULL);
10484 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10485 if (TREE_CODE (r) == VAR_DECL)
10487 /* Possibly limit visibility based on template args. */
10488 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10489 if (DECL_VISIBILITY_SPECIFIED (t))
10491 DECL_VISIBILITY_SPECIFIED (r) = 0;
10492 DECL_ATTRIBUTES (r)
10493 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10495 determine_visibility (r);
10500 /* A static data member declaration is always marked
10501 external when it is declared in-class, even if an
10502 initializer is present. We mimic the non-template
10503 processing here. */
10504 DECL_EXTERNAL (r) = 1;
10506 register_specialization (r, gen_tmpl, argvec, false, hash);
10507 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10508 SET_DECL_IMPLICIT_INSTANTIATION (r);
10510 else if (cp_unevaluated_operand)
10512 /* We're substituting this var in a decltype outside of its
10513 scope, such as for a lambda return type. Don't add it to
10514 local_specializations, do perform auto deduction. */
10515 tree auto_node = type_uses_auto (type);
10519 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10520 /*constant_expression_p=*/false);
10521 init = resolve_nondeduced_context (init);
10522 TREE_TYPE (r) = type
10523 = do_auto_deduction (type, init, auto_node);
10527 register_local_specialization (r, t);
10529 DECL_CHAIN (r) = NULL_TREE;
10531 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10533 args, complain, in_decl);
10535 /* Preserve a typedef that names a type. */
10536 if (is_typedef_decl (r))
10538 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10539 set_underlying_type (r);
10542 layout_decl (r, 0);
10547 gcc_unreachable ();
10552 /* Restore the file and line information. */
10553 input_location = saved_loc;
10558 /* Substitute into the ARG_TYPES of a function type. */
10561 tsubst_arg_types (tree arg_types,
10563 tsubst_flags_t complain,
10566 tree remaining_arg_types;
10567 tree type = NULL_TREE;
10569 tree expanded_args = NULL_TREE;
10572 if (!arg_types || arg_types == void_list_node)
10575 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10576 args, complain, in_decl);
10577 if (remaining_arg_types == error_mark_node)
10578 return error_mark_node;
10580 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10582 /* For a pack expansion, perform substitution on the
10583 entire expression. Later on, we'll handle the arguments
10585 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10586 args, complain, in_decl);
10588 if (TREE_CODE (expanded_args) == TREE_VEC)
10589 /* So that we'll spin through the parameters, one by one. */
10590 i = TREE_VEC_LENGTH (expanded_args);
10593 /* We only partially substituted into the parameter
10594 pack. Our type is TYPE_PACK_EXPANSION. */
10595 type = expanded_args;
10596 expanded_args = NULL_TREE;
10604 type = TREE_VEC_ELT (expanded_args, i);
10606 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10608 if (type == error_mark_node)
10609 return error_mark_node;
10610 if (VOID_TYPE_P (type))
10612 if (complain & tf_error)
10614 error ("invalid parameter type %qT", type);
10616 error ("in declaration %q+D", in_decl);
10618 return error_mark_node;
10621 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10622 top-level qualifiers as required. */
10623 type = cv_unqualified (type_decays_to (type));
10625 /* We do not substitute into default arguments here. The standard
10626 mandates that they be instantiated only when needed, which is
10627 done in build_over_call. */
10628 default_arg = TREE_PURPOSE (arg_types);
10630 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10632 /* We've instantiated a template before its default arguments
10633 have been parsed. This can happen for a nested template
10634 class, and is not an error unless we require the default
10635 argument in a call of this function. */
10636 remaining_arg_types =
10637 tree_cons (default_arg, type, remaining_arg_types);
10638 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10639 remaining_arg_types);
10642 remaining_arg_types =
10643 hash_tree_cons (default_arg, type, remaining_arg_types);
10646 return remaining_arg_types;
10649 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10650 *not* handle the exception-specification for FNTYPE, because the
10651 initial substitution of explicitly provided template parameters
10652 during argument deduction forbids substitution into the
10653 exception-specification:
10657 All references in the function type of the function template to the
10658 corresponding template parameters are replaced by the specified tem-
10659 plate argument values. If a substitution in a template parameter or
10660 in the function type of the function template results in an invalid
10661 type, type deduction fails. [Note: The equivalent substitution in
10662 exception specifications is done only when the function is instanti-
10663 ated, at which point a program is ill-formed if the substitution
10664 results in an invalid type.] */
10667 tsubst_function_type (tree t,
10669 tsubst_flags_t complain,
10676 /* The TYPE_CONTEXT is not used for function/method types. */
10677 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10679 /* Substitute the return type. */
10680 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10681 if (return_type == error_mark_node)
10682 return error_mark_node;
10683 /* The standard does not presently indicate that creation of a
10684 function type with an invalid return type is a deduction failure.
10685 However, that is clearly analogous to creating an array of "void"
10686 or a reference to a reference. This is core issue #486. */
10687 if (TREE_CODE (return_type) == ARRAY_TYPE
10688 || TREE_CODE (return_type) == FUNCTION_TYPE)
10690 if (complain & tf_error)
10692 if (TREE_CODE (return_type) == ARRAY_TYPE)
10693 error ("function returning an array");
10695 error ("function returning a function");
10697 return error_mark_node;
10700 /* Substitute the argument types. */
10701 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10702 complain, in_decl);
10703 if (arg_types == error_mark_node)
10704 return error_mark_node;
10706 /* Construct a new type node and return it. */
10707 if (TREE_CODE (t) == FUNCTION_TYPE)
10709 fntype = build_function_type (return_type, arg_types);
10710 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10714 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10715 if (! MAYBE_CLASS_TYPE_P (r))
10719 Type deduction may fail for any of the following
10722 -- Attempting to create "pointer to member of T" when T
10723 is not a class type. */
10724 if (complain & tf_error)
10725 error ("creating pointer to member function of non-class type %qT",
10727 return error_mark_node;
10730 fntype = build_method_type_directly (r, return_type,
10731 TREE_CHAIN (arg_types));
10733 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10738 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10739 ARGS into that specification, and return the substituted
10740 specification. If there is no specification, return NULL_TREE. */
10743 tsubst_exception_specification (tree fntype,
10745 tsubst_flags_t complain,
10752 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10753 new_specs = NULL_TREE;
10754 if (specs && TREE_PURPOSE (specs))
10756 /* A noexcept-specifier. */
10757 tree expr = TREE_PURPOSE (specs);
10758 if (expr == boolean_true_node || expr == boolean_false_node)
10762 /* Defer instantiation of noexcept-specifiers to avoid
10763 excessive instantiations (c++/49107). */
10764 new_specs = make_node (DEFERRED_NOEXCEPT);
10765 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
10767 /* We already partially instantiated this member template,
10768 so combine the new args with the old. */
10769 DEFERRED_NOEXCEPT_PATTERN (new_specs)
10770 = DEFERRED_NOEXCEPT_PATTERN (expr);
10771 DEFERRED_NOEXCEPT_ARGS (new_specs)
10772 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
10776 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
10777 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
10781 new_specs = tsubst_copy_and_build
10782 (expr, args, complain, in_decl, /*function_p=*/false,
10783 /*integral_constant_expression_p=*/true);
10784 new_specs = build_noexcept_spec (new_specs, complain);
10788 if (! TREE_VALUE (specs))
10795 tree expanded_specs = NULL_TREE;
10797 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
10799 /* Expand the pack expansion type. */
10800 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
10804 if (expanded_specs == error_mark_node)
10805 return error_mark_node;
10806 else if (TREE_CODE (expanded_specs) == TREE_VEC)
10807 len = TREE_VEC_LENGTH (expanded_specs);
10810 /* We're substituting into a member template, so
10811 we got a TYPE_PACK_EXPANSION back. Add that
10812 expansion and move on. */
10813 gcc_assert (TREE_CODE (expanded_specs)
10814 == TYPE_PACK_EXPANSION);
10815 new_specs = add_exception_specifier (new_specs,
10818 specs = TREE_CHAIN (specs);
10823 for (i = 0; i < len; ++i)
10825 if (expanded_specs)
10826 spec = TREE_VEC_ELT (expanded_specs, i);
10828 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
10829 if (spec == error_mark_node)
10831 new_specs = add_exception_specifier (new_specs, spec,
10835 specs = TREE_CHAIN (specs);
10841 /* Take the tree structure T and replace template parameters used
10842 therein with the argument vector ARGS. IN_DECL is an associated
10843 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
10844 Issue error and warning messages under control of COMPLAIN. Note
10845 that we must be relatively non-tolerant of extensions here, in
10846 order to preserve conformance; if we allow substitutions that
10847 should not be allowed, we may allow argument deductions that should
10848 not succeed, and therefore report ambiguous overload situations
10849 where there are none. In theory, we could allow the substitution,
10850 but indicate that it should have failed, and allow our caller to
10851 make sure that the right thing happens, but we don't try to do this
10854 This function is used for dealing with types, decls and the like;
10855 for expressions, use tsubst_expr or tsubst_copy. */
10858 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10860 enum tree_code code;
10863 if (t == NULL_TREE || t == error_mark_node
10864 || t == integer_type_node
10865 || t == void_type_node
10866 || t == char_type_node
10867 || t == unknown_type_node
10868 || TREE_CODE (t) == NAMESPACE_DECL
10869 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
10873 return tsubst_decl (t, args, complain);
10875 if (args == NULL_TREE)
10878 code = TREE_CODE (t);
10880 if (code == IDENTIFIER_NODE)
10881 type = IDENTIFIER_TYPE_VALUE (t);
10883 type = TREE_TYPE (t);
10885 gcc_assert (type != unknown_type_node);
10887 /* Reuse typedefs. We need to do this to handle dependent attributes,
10888 such as attribute aligned. */
10890 && typedef_variant_p (t))
10892 tree decl = TYPE_NAME (t);
10894 if (DECL_CLASS_SCOPE_P (decl)
10895 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
10896 && uses_template_parms (DECL_CONTEXT (decl)))
10898 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
10899 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
10900 r = retrieve_specialization (tmpl, gen_args, 0);
10902 else if (DECL_FUNCTION_SCOPE_P (decl)
10903 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
10904 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
10905 r = retrieve_local_specialization (decl);
10907 /* The typedef is from a non-template context. */
10913 r = cp_build_qualified_type_real
10914 (r, cp_type_quals (t) | cp_type_quals (r),
10915 complain | tf_ignore_bad_quals);
10918 /* Else we must be instantiating the typedef, so fall through. */
10922 && code != TYPENAME_TYPE
10923 && code != TEMPLATE_TYPE_PARM
10924 && code != IDENTIFIER_NODE
10925 && code != FUNCTION_TYPE
10926 && code != METHOD_TYPE)
10927 type = tsubst (type, args, complain, in_decl);
10928 if (type == error_mark_node)
10929 return error_mark_node;
10935 case ENUMERAL_TYPE:
10936 return tsubst_aggr_type (t, args, complain, in_decl,
10937 /*entering_scope=*/0);
10940 case IDENTIFIER_NODE:
10951 if (t == integer_type_node)
10954 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
10955 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
10959 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
10961 max = tsubst_expr (omax, args, complain, in_decl,
10962 /*integral_constant_expression_p=*/false);
10964 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
10966 if (TREE_CODE (max) == NOP_EXPR
10967 && TREE_SIDE_EFFECTS (omax)
10968 && !TREE_TYPE (max))
10969 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
10971 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
10972 with TREE_SIDE_EFFECTS that indicates this is not an integral
10973 constant expression. */
10974 if (processing_template_decl
10975 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
10977 gcc_assert (TREE_CODE (max) == NOP_EXPR);
10978 TREE_SIDE_EFFECTS (max) = 1;
10981 return compute_array_index_type (NULL_TREE, max, complain);
10984 case TEMPLATE_TYPE_PARM:
10985 case TEMPLATE_TEMPLATE_PARM:
10986 case BOUND_TEMPLATE_TEMPLATE_PARM:
10987 case TEMPLATE_PARM_INDEX:
10992 tree arg = NULL_TREE;
10996 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10997 template_parm_level_and_index (t, &level, &idx);
10999 levels = TMPL_ARGS_DEPTH (args);
11000 if (level <= levels)
11002 arg = TMPL_ARG (args, level, idx);
11004 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11005 /* See through ARGUMENT_PACK_SELECT arguments. */
11006 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11009 if (arg == error_mark_node)
11010 return error_mark_node;
11011 else if (arg != NULL_TREE)
11013 if (ARGUMENT_PACK_P (arg))
11014 /* If ARG is an argument pack, we don't actually want to
11015 perform a substitution here, because substitutions
11016 for argument packs are only done
11017 element-by-element. We can get to this point when
11018 substituting the type of a non-type template
11019 parameter pack, when that type actually contains
11020 template parameter packs from an outer template, e.g.,
11022 template<typename... Types> struct A {
11023 template<Types... Values> struct B { };
11027 if (code == TEMPLATE_TYPE_PARM)
11030 gcc_assert (TYPE_P (arg));
11032 quals = cp_type_quals (arg) | cp_type_quals (t);
11034 return cp_build_qualified_type_real
11035 (arg, quals, complain | tf_ignore_bad_quals);
11037 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11039 /* We are processing a type constructed from a
11040 template template parameter. */
11041 tree argvec = tsubst (TYPE_TI_ARGS (t),
11042 args, complain, in_decl);
11043 if (argvec == error_mark_node)
11044 return error_mark_node;
11046 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11047 are resolving nested-types in the signature of a
11048 member function templates. Otherwise ARG is a
11049 TEMPLATE_DECL and is the real template to be
11051 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11052 arg = TYPE_NAME (arg);
11054 r = lookup_template_class (arg,
11056 DECL_CONTEXT (arg),
11057 /*entering_scope=*/0,
11059 return cp_build_qualified_type_real
11060 (r, cp_type_quals (t), complain);
11063 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11064 return convert_from_reference (unshare_expr (arg));
11068 /* This can happen during the attempted tsubst'ing in
11069 unify. This means that we don't yet have any information
11070 about the template parameter in question. */
11073 /* If we get here, we must have been looking at a parm for a
11074 more deeply nested template. Make a new version of this
11075 template parameter, but with a lower level. */
11078 case TEMPLATE_TYPE_PARM:
11079 case TEMPLATE_TEMPLATE_PARM:
11080 case BOUND_TEMPLATE_TEMPLATE_PARM:
11081 if (cp_type_quals (t))
11083 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11084 r = cp_build_qualified_type_real
11085 (r, cp_type_quals (t),
11086 complain | (code == TEMPLATE_TYPE_PARM
11087 ? tf_ignore_bad_quals : 0));
11092 TEMPLATE_TYPE_PARM_INDEX (r)
11093 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11094 r, levels, args, complain);
11095 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11096 TYPE_MAIN_VARIANT (r) = r;
11097 TYPE_POINTER_TO (r) = NULL_TREE;
11098 TYPE_REFERENCE_TO (r) = NULL_TREE;
11100 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11101 /* We have reduced the level of the template
11102 template parameter, but not the levels of its
11103 template parameters, so canonical_type_parameter
11104 will not be able to find the canonical template
11105 template parameter for this level. Thus, we
11106 require structural equality checking to compare
11107 TEMPLATE_TEMPLATE_PARMs. */
11108 SET_TYPE_STRUCTURAL_EQUALITY (r);
11109 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11110 SET_TYPE_STRUCTURAL_EQUALITY (r);
11112 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11114 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11116 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11117 complain, in_decl);
11118 if (argvec == error_mark_node)
11119 return error_mark_node;
11121 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11122 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11127 case TEMPLATE_PARM_INDEX:
11128 r = reduce_template_parm_level (t, type, levels, args, complain);
11132 gcc_unreachable ();
11140 tree purpose, value, chain;
11142 if (t == void_list_node)
11145 purpose = TREE_PURPOSE (t);
11148 purpose = tsubst (purpose, args, complain, in_decl);
11149 if (purpose == error_mark_node)
11150 return error_mark_node;
11152 value = TREE_VALUE (t);
11155 value = tsubst (value, args, complain, in_decl);
11156 if (value == error_mark_node)
11157 return error_mark_node;
11159 chain = TREE_CHAIN (t);
11160 if (chain && chain != void_type_node)
11162 chain = tsubst (chain, args, complain, in_decl);
11163 if (chain == error_mark_node)
11164 return error_mark_node;
11166 if (purpose == TREE_PURPOSE (t)
11167 && value == TREE_VALUE (t)
11168 && chain == TREE_CHAIN (t))
11170 return hash_tree_cons (purpose, value, chain);
11174 /* We should never be tsubsting a binfo. */
11175 gcc_unreachable ();
11178 /* A vector of template arguments. */
11179 gcc_assert (!type);
11180 return tsubst_template_args (t, args, complain, in_decl);
11183 case REFERENCE_TYPE:
11185 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11190 Type deduction may fail for any of the following
11193 -- Attempting to create a pointer to reference type.
11194 -- Attempting to create a reference to a reference type or
11195 a reference to void.
11197 Core issue 106 says that creating a reference to a reference
11198 during instantiation is no longer a cause for failure. We
11199 only enforce this check in strict C++98 mode. */
11200 if ((TREE_CODE (type) == REFERENCE_TYPE
11201 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11202 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11204 static location_t last_loc;
11206 /* We keep track of the last time we issued this error
11207 message to avoid spewing a ton of messages during a
11208 single bad template instantiation. */
11209 if (complain & tf_error
11210 && last_loc != input_location)
11212 if (TREE_CODE (type) == VOID_TYPE)
11213 error ("forming reference to void");
11214 else if (code == POINTER_TYPE)
11215 error ("forming pointer to reference type %qT", type);
11217 error ("forming reference to reference type %qT", type);
11218 last_loc = input_location;
11221 return error_mark_node;
11223 else if (code == POINTER_TYPE)
11225 r = build_pointer_type (type);
11226 if (TREE_CODE (type) == METHOD_TYPE)
11227 r = build_ptrmemfunc_type (r);
11229 else if (TREE_CODE (type) == REFERENCE_TYPE)
11230 /* In C++0x, during template argument substitution, when there is an
11231 attempt to create a reference to a reference type, reference
11232 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11234 "If a template-argument for a template-parameter T names a type
11235 that is a reference to a type A, an attempt to create the type
11236 'lvalue reference to cv T' creates the type 'lvalue reference to
11237 A,' while an attempt to create the type type rvalue reference to
11238 cv T' creates the type T"
11240 r = cp_build_reference_type
11242 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11244 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11245 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11247 if (r != error_mark_node)
11248 /* Will this ever be needed for TYPE_..._TO values? */
11255 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11256 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11260 Type deduction may fail for any of the following
11263 -- Attempting to create "pointer to member of T" when T
11264 is not a class type. */
11265 if (complain & tf_error)
11266 error ("creating pointer to member of non-class type %qT", r);
11267 return error_mark_node;
11269 if (TREE_CODE (type) == REFERENCE_TYPE)
11271 if (complain & tf_error)
11272 error ("creating pointer to member reference type %qT", type);
11273 return error_mark_node;
11275 if (TREE_CODE (type) == VOID_TYPE)
11277 if (complain & tf_error)
11278 error ("creating pointer to member of type void");
11279 return error_mark_node;
11281 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11282 if (TREE_CODE (type) == FUNCTION_TYPE)
11284 /* The type of the implicit object parameter gets its
11285 cv-qualifiers from the FUNCTION_TYPE. */
11287 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11288 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11289 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11293 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11297 case FUNCTION_TYPE:
11302 fntype = tsubst_function_type (t, args, complain, in_decl);
11303 if (fntype == error_mark_node)
11304 return error_mark_node;
11306 /* Substitute the exception specification. */
11307 specs = tsubst_exception_specification (t, args, complain,
11308 in_decl, /*defer_ok*/true);
11309 if (specs == error_mark_node)
11310 return error_mark_node;
11312 fntype = build_exception_variant (fntype, specs);
11317 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11318 if (domain == error_mark_node)
11319 return error_mark_node;
11321 /* As an optimization, we avoid regenerating the array type if
11322 it will obviously be the same as T. */
11323 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11326 /* These checks should match the ones in grokdeclarator.
11330 The deduction may fail for any of the following reasons:
11332 -- Attempting to create an array with an element type that
11333 is void, a function type, or a reference type, or [DR337]
11334 an abstract class type. */
11335 if (TREE_CODE (type) == VOID_TYPE
11336 || TREE_CODE (type) == FUNCTION_TYPE
11337 || TREE_CODE (type) == REFERENCE_TYPE)
11339 if (complain & tf_error)
11340 error ("creating array of %qT", type);
11341 return error_mark_node;
11343 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11345 if (complain & tf_error)
11346 error ("creating array of %qT, which is an abstract class type",
11348 return error_mark_node;
11351 r = build_cplus_array_type (type, domain);
11353 if (TYPE_USER_ALIGN (t))
11355 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11356 TYPE_USER_ALIGN (r) = 1;
11362 case TYPENAME_TYPE:
11364 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11365 in_decl, /*entering_scope=*/1);
11366 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11367 complain, in_decl);
11369 if (ctx == error_mark_node || f == error_mark_node)
11370 return error_mark_node;
11372 if (!MAYBE_CLASS_TYPE_P (ctx))
11374 if (complain & tf_error)
11375 error ("%qT is not a class, struct, or union type", ctx);
11376 return error_mark_node;
11378 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11380 /* Normally, make_typename_type does not require that the CTX
11381 have complete type in order to allow things like:
11383 template <class T> struct S { typename S<T>::X Y; };
11385 But, such constructs have already been resolved by this
11386 point, so here CTX really should have complete type, unless
11387 it's a partial instantiation. */
11388 ctx = complete_type (ctx);
11389 if (!COMPLETE_TYPE_P (ctx))
11391 if (complain & tf_error)
11392 cxx_incomplete_type_error (NULL_TREE, ctx);
11393 return error_mark_node;
11397 f = make_typename_type (ctx, f, typename_type,
11398 (complain & tf_error) | tf_keep_type_decl);
11399 if (f == error_mark_node)
11401 if (TREE_CODE (f) == TYPE_DECL)
11403 complain |= tf_ignore_bad_quals;
11407 if (TREE_CODE (f) != TYPENAME_TYPE)
11409 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11411 if (complain & tf_error)
11412 error ("%qT resolves to %qT, which is not an enumeration type",
11415 return error_mark_node;
11417 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11419 if (complain & tf_error)
11420 error ("%qT resolves to %qT, which is is not a class type",
11423 return error_mark_node;
11427 return cp_build_qualified_type_real
11428 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11431 case UNBOUND_CLASS_TEMPLATE:
11433 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11434 in_decl, /*entering_scope=*/1);
11435 tree name = TYPE_IDENTIFIER (t);
11436 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11438 if (ctx == error_mark_node || name == error_mark_node)
11439 return error_mark_node;
11442 parm_list = tsubst_template_parms (parm_list, args, complain);
11443 return make_unbound_class_template (ctx, name, parm_list, complain);
11450 ++cp_unevaluated_operand;
11451 ++c_inhibit_evaluation_warnings;
11453 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11455 /*integral_constant_expression_p=*/false);
11457 --cp_unevaluated_operand;
11458 --c_inhibit_evaluation_warnings;
11460 type = finish_typeof (type);
11461 return cp_build_qualified_type_real (type,
11463 | cp_type_quals (type),
11467 case DECLTYPE_TYPE:
11471 ++cp_unevaluated_operand;
11472 ++c_inhibit_evaluation_warnings;
11474 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11476 /*integral_constant_expression_p=*/false);
11478 --cp_unevaluated_operand;
11479 --c_inhibit_evaluation_warnings;
11481 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11482 type = lambda_capture_field_type (type);
11483 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11484 type = lambda_proxy_type (type);
11486 type = finish_decltype_type
11487 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11488 return cp_build_qualified_type_real (type,
11490 | cp_type_quals (type),
11494 case UNDERLYING_TYPE:
11496 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11497 complain, in_decl);
11498 return finish_underlying_type (type);
11501 case TYPE_ARGUMENT_PACK:
11502 case NONTYPE_ARGUMENT_PACK:
11504 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11506 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11510 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11512 /* For template nontype argument packs, also substitute into
11514 if (code == NONTYPE_ARGUMENT_PACK)
11515 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11533 /* We should use one of the expression tsubsts for these codes. */
11534 gcc_unreachable ();
11537 sorry ("use of %qs in template", tree_code_name [(int) code]);
11538 return error_mark_node;
11542 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11543 type of the expression on the left-hand side of the "." or "->"
11547 tsubst_baselink (tree baselink, tree object_type,
11548 tree args, tsubst_flags_t complain, tree in_decl)
11551 tree qualifying_scope;
11554 tree template_args = 0;
11555 bool template_id_p = false;
11557 /* A baselink indicates a function from a base class. Both the
11558 BASELINK_ACCESS_BINFO and the base class referenced may
11559 indicate bases of the template class, rather than the
11560 instantiated class. In addition, lookups that were not
11561 ambiguous before may be ambiguous now. Therefore, we perform
11562 the lookup again. */
11563 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11564 qualifying_scope = tsubst (qualifying_scope, args,
11565 complain, in_decl);
11566 fns = BASELINK_FUNCTIONS (baselink);
11567 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11568 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11570 template_id_p = true;
11571 template_args = TREE_OPERAND (fns, 1);
11572 fns = TREE_OPERAND (fns, 0);
11574 template_args = tsubst_template_args (template_args, args,
11575 complain, in_decl);
11577 name = DECL_NAME (get_first_fn (fns));
11578 if (IDENTIFIER_TYPENAME_P (name))
11579 name = mangle_conv_op_name_for_type (optype);
11580 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11582 return error_mark_node;
11584 /* If lookup found a single function, mark it as used at this
11585 point. (If it lookup found multiple functions the one selected
11586 later by overload resolution will be marked as used at that
11588 if (BASELINK_P (baselink))
11589 fns = BASELINK_FUNCTIONS (baselink);
11590 if (!template_id_p && !really_overloaded_fn (fns))
11591 mark_used (OVL_CURRENT (fns));
11593 /* Add back the template arguments, if present. */
11594 if (BASELINK_P (baselink) && template_id_p)
11595 BASELINK_FUNCTIONS (baselink)
11596 = build_nt (TEMPLATE_ID_EXPR,
11597 BASELINK_FUNCTIONS (baselink),
11599 /* Update the conversion operator type. */
11600 BASELINK_OPTYPE (baselink) = optype;
11603 object_type = current_class_type;
11604 return adjust_result_of_qualified_name_lookup (baselink,
11609 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11610 true if the qualified-id will be a postfix-expression in-and-of
11611 itself; false if more of the postfix-expression follows the
11612 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11616 tsubst_qualified_id (tree qualified_id, tree args,
11617 tsubst_flags_t complain, tree in_decl,
11618 bool done, bool address_p)
11624 tree template_args;
11626 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11628 /* Figure out what name to look up. */
11629 name = TREE_OPERAND (qualified_id, 1);
11630 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11632 is_template = true;
11633 template_args = TREE_OPERAND (name, 1);
11635 template_args = tsubst_template_args (template_args, args,
11636 complain, in_decl);
11637 name = TREE_OPERAND (name, 0);
11641 is_template = false;
11642 template_args = NULL_TREE;
11645 /* Substitute into the qualifying scope. When there are no ARGS, we
11646 are just trying to simplify a non-dependent expression. In that
11647 case the qualifying scope may be dependent, and, in any case,
11648 substituting will not help. */
11649 scope = TREE_OPERAND (qualified_id, 0);
11652 scope = tsubst (scope, args, complain, in_decl);
11653 expr = tsubst_copy (name, args, complain, in_decl);
11658 if (dependent_scope_p (scope))
11661 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11662 return build_qualified_name (NULL_TREE, scope, expr,
11663 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11666 if (!BASELINK_P (name) && !DECL_P (expr))
11668 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11670 /* A BIT_NOT_EXPR is used to represent a destructor. */
11671 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11673 error ("qualifying type %qT does not match destructor name ~%qT",
11674 scope, TREE_OPERAND (expr, 0));
11675 expr = error_mark_node;
11678 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11679 /*is_type_p=*/0, false);
11682 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11683 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11684 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11686 if (complain & tf_error)
11688 error ("dependent-name %qE is parsed as a non-type, but "
11689 "instantiation yields a type", qualified_id);
11690 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11692 return error_mark_node;
11698 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11700 /* Remember that there was a reference to this entity. */
11704 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
11706 if (complain & tf_error)
11707 qualified_name_lookup_error (scope,
11708 TREE_OPERAND (qualified_id, 1),
11709 expr, input_location);
11710 return error_mark_node;
11714 expr = lookup_template_function (expr, template_args);
11716 if (expr == error_mark_node && complain & tf_error)
11717 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
11718 expr, input_location);
11719 else if (TYPE_P (scope))
11721 expr = (adjust_result_of_qualified_name_lookup
11722 (expr, scope, current_class_type));
11723 expr = (finish_qualified_id_expr
11724 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
11725 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
11726 /*template_arg_p=*/false));
11729 /* Expressions do not generally have reference type. */
11730 if (TREE_CODE (expr) != SCOPE_REF
11731 /* However, if we're about to form a pointer-to-member, we just
11732 want the referenced member referenced. */
11733 && TREE_CODE (expr) != OFFSET_REF)
11734 expr = convert_from_reference (expr);
11739 /* Like tsubst, but deals with expressions. This function just replaces
11740 template parms; to finish processing the resultant expression, use
11741 tsubst_copy_and_build or tsubst_expr. */
11744 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11746 enum tree_code code;
11749 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
11752 code = TREE_CODE (t);
11757 r = retrieve_local_specialization (t);
11763 /* We get here for a use of 'this' in an NSDMI. */
11764 if (DECL_NAME (t) == this_identifier
11765 && at_function_scope_p ()
11766 && DECL_CONSTRUCTOR_P (current_function_decl))
11767 return current_class_ptr;
11769 /* This can happen for a parameter name used later in a function
11770 declaration (such as in a late-specified return type). Just
11771 make a dummy decl, since it's only used for its type. */
11772 gcc_assert (cp_unevaluated_operand != 0);
11773 /* We copy T because want to tsubst the PARM_DECL only,
11774 not the following PARM_DECLs that are chained to T. */
11776 r = tsubst_decl (c, args, complain);
11777 /* Give it the template pattern as its context; its true context
11778 hasn't been instantiated yet and this is good enough for
11780 DECL_CONTEXT (r) = DECL_CONTEXT (t);
11783 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
11784 r = ARGUMENT_PACK_SELECT_ARG (r);
11793 if (DECL_TEMPLATE_PARM_P (t))
11794 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
11795 /* There is no need to substitute into namespace-scope
11797 if (DECL_NAMESPACE_SCOPE_P (t))
11799 /* If ARGS is NULL, then T is known to be non-dependent. */
11800 if (args == NULL_TREE)
11801 return integral_constant_value (t);
11803 /* Unfortunately, we cannot just call lookup_name here.
11806 template <int I> int f() {
11808 struct S { void g() { E e = a; } };
11811 When we instantiate f<7>::S::g(), say, lookup_name is not
11812 clever enough to find f<7>::a. */
11814 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
11815 /*entering_scope=*/0);
11817 for (v = TYPE_VALUES (enum_type);
11819 v = TREE_CHAIN (v))
11820 if (TREE_PURPOSE (v) == DECL_NAME (t))
11821 return TREE_VALUE (v);
11823 /* We didn't find the name. That should never happen; if
11824 name-lookup found it during preliminary parsing, we
11825 should find it again here during instantiation. */
11826 gcc_unreachable ();
11831 if (DECL_CONTEXT (t))
11835 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
11836 /*entering_scope=*/1);
11837 if (ctx != DECL_CONTEXT (t))
11839 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
11842 if (complain & tf_error)
11843 error ("using invalid field %qD", t);
11844 return error_mark_node;
11853 case FUNCTION_DECL:
11854 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
11855 || local_variable_p (t))
11856 t = tsubst (t, args, complain, in_decl);
11861 /* An OVERLOAD will always be a non-dependent overload set; an
11862 overload set from function scope will just be represented with an
11863 IDENTIFIER_NODE, and from class scope with a BASELINK. */
11864 gcc_assert (!uses_template_parms (t));
11868 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
11870 case TEMPLATE_DECL:
11871 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
11872 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
11873 args, complain, in_decl);
11874 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
11875 return tsubst (t, args, complain, in_decl);
11876 else if (DECL_CLASS_SCOPE_P (t)
11877 && uses_template_parms (DECL_CONTEXT (t)))
11879 /* Template template argument like the following example need
11882 template <template <class> class TT> struct C {};
11883 template <class T> struct D {
11884 template <class U> struct E {};
11889 We are processing the template argument `E' in #1 for
11890 the template instantiation #2. Originally, `E' is a
11891 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
11892 have to substitute this with one having context `D<int>'. */
11894 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
11895 return lookup_field (context, DECL_NAME(t), 0, false);
11898 /* Ordinary template template argument. */
11902 case REINTERPRET_CAST_EXPR:
11903 case CONST_CAST_EXPR:
11904 case STATIC_CAST_EXPR:
11905 case DYNAMIC_CAST_EXPR:
11906 case IMPLICIT_CONV_EXPR:
11910 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11911 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11914 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11920 ++cp_unevaluated_operand;
11921 ++c_inhibit_evaluation_warnings;
11922 /* We only want to compute the number of arguments. */
11923 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
11924 complain, in_decl);
11925 --cp_unevaluated_operand;
11926 --c_inhibit_evaluation_warnings;
11928 if (TREE_CODE (expanded) == TREE_VEC)
11929 len = TREE_VEC_LENGTH (expanded);
11931 if (expanded == error_mark_node)
11932 return error_mark_node;
11933 else if (PACK_EXPANSION_P (expanded)
11934 || (TREE_CODE (expanded) == TREE_VEC
11936 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
11938 if (TREE_CODE (expanded) == TREE_VEC)
11939 expanded = TREE_VEC_ELT (expanded, len - 1);
11941 if (TYPE_P (expanded))
11942 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
11943 complain & tf_error);
11945 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
11946 complain & tf_error);
11949 return build_int_cst (size_type_node, len);
11955 case TRUTH_NOT_EXPR:
11958 case UNARY_PLUS_EXPR: /* Unary + */
11960 case AT_ENCODE_EXPR:
11964 case REALPART_EXPR:
11965 case IMAGPART_EXPR:
11967 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
11968 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11970 case COMPONENT_REF:
11975 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11976 name = TREE_OPERAND (t, 1);
11977 if (TREE_CODE (name) == BIT_NOT_EXPR)
11979 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11980 complain, in_decl);
11981 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11983 else if (TREE_CODE (name) == SCOPE_REF
11984 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11986 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11987 complain, in_decl);
11988 name = TREE_OPERAND (name, 1);
11989 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11990 complain, in_decl);
11991 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11992 name = build_qualified_name (/*type=*/NULL_TREE,
11994 /*template_p=*/false);
11996 else if (BASELINK_P (name))
11997 name = tsubst_baselink (name,
11998 non_reference (TREE_TYPE (object)),
12002 name = tsubst_copy (name, args, complain, in_decl);
12003 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12009 case TRUNC_DIV_EXPR:
12010 case CEIL_DIV_EXPR:
12011 case FLOOR_DIV_EXPR:
12012 case ROUND_DIV_EXPR:
12013 case EXACT_DIV_EXPR:
12017 case TRUNC_MOD_EXPR:
12018 case FLOOR_MOD_EXPR:
12019 case TRUTH_ANDIF_EXPR:
12020 case TRUTH_ORIF_EXPR:
12021 case TRUTH_AND_EXPR:
12022 case TRUTH_OR_EXPR:
12035 case COMPOUND_EXPR:
12038 case PREDECREMENT_EXPR:
12039 case PREINCREMENT_EXPR:
12040 case POSTDECREMENT_EXPR:
12041 case POSTINCREMENT_EXPR:
12043 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12044 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12047 return build_qualified_name (/*type=*/NULL_TREE,
12048 tsubst_copy (TREE_OPERAND (t, 0),
12049 args, complain, in_decl),
12050 tsubst_copy (TREE_OPERAND (t, 1),
12051 args, complain, in_decl),
12052 QUALIFIED_NAME_IS_TEMPLATE (t));
12057 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12058 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12059 NULL_TREE, NULL_TREE);
12063 int n = VL_EXP_OPERAND_LENGTH (t);
12064 tree result = build_vl_exp (CALL_EXPR, n);
12066 for (i = 0; i < n; i++)
12067 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12068 complain, in_decl);
12074 case PSEUDO_DTOR_EXPR:
12077 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12078 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12079 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12080 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12087 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12088 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12089 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12090 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12097 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12098 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12099 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12100 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12104 case TEMPLATE_ID_EXPR:
12106 /* Substituted template arguments */
12107 tree fn = TREE_OPERAND (t, 0);
12108 tree targs = TREE_OPERAND (t, 1);
12110 fn = tsubst_copy (fn, args, complain, in_decl);
12112 targs = tsubst_template_args (targs, args, complain, in_decl);
12114 return lookup_template_function (fn, targs);
12119 tree purpose, value, chain;
12121 if (t == void_list_node)
12124 purpose = TREE_PURPOSE (t);
12126 purpose = tsubst_copy (purpose, args, complain, in_decl);
12127 value = TREE_VALUE (t);
12129 value = tsubst_copy (value, args, complain, in_decl);
12130 chain = TREE_CHAIN (t);
12131 if (chain && chain != void_type_node)
12132 chain = tsubst_copy (chain, args, complain, in_decl);
12133 if (purpose == TREE_PURPOSE (t)
12134 && value == TREE_VALUE (t)
12135 && chain == TREE_CHAIN (t))
12137 return tree_cons (purpose, value, chain);
12142 case ENUMERAL_TYPE:
12144 case TEMPLATE_TYPE_PARM:
12145 case TEMPLATE_TEMPLATE_PARM:
12146 case BOUND_TEMPLATE_TEMPLATE_PARM:
12147 case TEMPLATE_PARM_INDEX:
12149 case REFERENCE_TYPE:
12151 case FUNCTION_TYPE:
12154 case TYPENAME_TYPE:
12155 case UNBOUND_CLASS_TEMPLATE:
12157 case DECLTYPE_TYPE:
12159 return tsubst (t, args, complain, in_decl);
12161 case IDENTIFIER_NODE:
12162 if (IDENTIFIER_TYPENAME_P (t))
12164 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12165 return mangle_conv_op_name_for_type (new_type);
12171 /* This is handled by tsubst_copy_and_build. */
12172 gcc_unreachable ();
12175 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12177 tsubst (TREE_TYPE (t), args, complain, in_decl));
12179 case CLEANUP_POINT_EXPR:
12180 /* We shouldn't have built any of these during initial template
12181 generation. Instead, they should be built during instantiation
12182 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12183 gcc_unreachable ();
12187 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12188 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12189 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12190 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12191 mark_used (TREE_OPERAND (r, 1));
12194 case EXPR_PACK_EXPANSION:
12195 error ("invalid use of pack expansion expression");
12196 return error_mark_node;
12198 case NONTYPE_ARGUMENT_PACK:
12199 error ("use %<...%> to expand argument pack");
12200 return error_mark_node;
12207 /* Instantiate any typedefs in the type. */
12208 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12209 r = fold_convert (type, t);
12210 gcc_assert (TREE_CODE (r) == code);
12215 /* These can sometimes show up in a partial instantiation, but never
12216 involve template parms. */
12217 gcc_assert (!uses_template_parms (t));
12221 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12222 gcc_checking_assert (false);
12227 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12230 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12233 tree new_clauses = NULL, nc, oc;
12235 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12237 nc = copy_node (oc);
12238 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12241 switch (OMP_CLAUSE_CODE (nc))
12243 case OMP_CLAUSE_LASTPRIVATE:
12244 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12246 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12247 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12248 in_decl, /*integral_constant_expression_p=*/false);
12249 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12250 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12253 case OMP_CLAUSE_PRIVATE:
12254 case OMP_CLAUSE_SHARED:
12255 case OMP_CLAUSE_FIRSTPRIVATE:
12256 case OMP_CLAUSE_REDUCTION:
12257 case OMP_CLAUSE_COPYIN:
12258 case OMP_CLAUSE_COPYPRIVATE:
12259 case OMP_CLAUSE_IF:
12260 case OMP_CLAUSE_NUM_THREADS:
12261 case OMP_CLAUSE_SCHEDULE:
12262 case OMP_CLAUSE_COLLAPSE:
12263 case OMP_CLAUSE_FINAL:
12264 OMP_CLAUSE_OPERAND (nc, 0)
12265 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12266 in_decl, /*integral_constant_expression_p=*/false);
12268 case OMP_CLAUSE_NOWAIT:
12269 case OMP_CLAUSE_ORDERED:
12270 case OMP_CLAUSE_DEFAULT:
12271 case OMP_CLAUSE_UNTIED:
12272 case OMP_CLAUSE_MERGEABLE:
12275 gcc_unreachable ();
12279 return finish_omp_clauses (nreverse (new_clauses));
12282 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12285 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12288 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12290 tree purpose, value, chain;
12295 if (TREE_CODE (t) != TREE_LIST)
12296 return tsubst_copy_and_build (t, args, complain, in_decl,
12297 /*function_p=*/false,
12298 /*integral_constant_expression_p=*/false);
12300 if (t == void_list_node)
12303 purpose = TREE_PURPOSE (t);
12305 purpose = RECUR (purpose);
12306 value = TREE_VALUE (t);
12307 if (value && TREE_CODE (value) != LABEL_DECL)
12308 value = RECUR (value);
12309 chain = TREE_CHAIN (t);
12310 if (chain && chain != void_type_node)
12311 chain = RECUR (chain);
12312 return tree_cons (purpose, value, chain);
12316 /* Substitute one OMP_FOR iterator. */
12319 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12320 tree condv, tree incrv, tree *clauses,
12321 tree args, tsubst_flags_t complain, tree in_decl,
12322 bool integral_constant_expression_p)
12324 #define RECUR(NODE) \
12325 tsubst_expr ((NODE), args, complain, in_decl, \
12326 integral_constant_expression_p)
12327 tree decl, init, cond, incr, auto_node;
12329 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12330 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12331 decl = RECUR (TREE_OPERAND (init, 0));
12332 init = TREE_OPERAND (init, 1);
12333 auto_node = type_uses_auto (TREE_TYPE (decl));
12334 if (auto_node && init)
12336 tree init_expr = init;
12337 if (TREE_CODE (init_expr) == DECL_EXPR)
12338 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12339 init_expr = RECUR (init_expr);
12341 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12343 gcc_assert (!type_dependent_expression_p (decl));
12345 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12347 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12348 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12349 if (TREE_CODE (incr) == MODIFY_EXPR)
12350 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12351 RECUR (TREE_OPERAND (incr, 1)),
12354 incr = RECUR (incr);
12355 TREE_VEC_ELT (declv, i) = decl;
12356 TREE_VEC_ELT (initv, i) = init;
12357 TREE_VEC_ELT (condv, i) = cond;
12358 TREE_VEC_ELT (incrv, i) = incr;
12362 if (init && TREE_CODE (init) != DECL_EXPR)
12365 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12367 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12368 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12369 && OMP_CLAUSE_DECL (c) == decl)
12371 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12372 && OMP_CLAUSE_DECL (c) == decl)
12373 error ("iteration variable %qD should not be firstprivate", decl);
12374 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12375 && OMP_CLAUSE_DECL (c) == decl)
12376 error ("iteration variable %qD should not be reduction", decl);
12380 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12381 OMP_CLAUSE_DECL (c) = decl;
12382 c = finish_omp_clauses (c);
12385 OMP_CLAUSE_CHAIN (c) = *clauses;
12390 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12391 if (COMPARISON_CLASS_P (cond))
12392 cond = build2 (TREE_CODE (cond), boolean_type_node,
12393 RECUR (TREE_OPERAND (cond, 0)),
12394 RECUR (TREE_OPERAND (cond, 1)));
12396 cond = RECUR (cond);
12397 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12398 switch (TREE_CODE (incr))
12400 case PREINCREMENT_EXPR:
12401 case PREDECREMENT_EXPR:
12402 case POSTINCREMENT_EXPR:
12403 case POSTDECREMENT_EXPR:
12404 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12405 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12408 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12409 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12411 tree rhs = TREE_OPERAND (incr, 1);
12412 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12413 RECUR (TREE_OPERAND (incr, 0)),
12414 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12415 RECUR (TREE_OPERAND (rhs, 0)),
12416 RECUR (TREE_OPERAND (rhs, 1))));
12419 incr = RECUR (incr);
12422 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12423 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12425 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12426 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12427 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12428 TREE_TYPE (decl), lhs,
12429 RECUR (TREE_OPERAND (incr, 2))));
12431 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12432 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12433 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12435 tree rhs = TREE_OPERAND (incr, 2);
12436 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12437 RECUR (TREE_OPERAND (incr, 0)),
12438 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12439 RECUR (TREE_OPERAND (rhs, 0)),
12440 RECUR (TREE_OPERAND (rhs, 1))));
12443 incr = RECUR (incr);
12446 incr = RECUR (incr);
12450 TREE_VEC_ELT (declv, i) = decl;
12451 TREE_VEC_ELT (initv, i) = init;
12452 TREE_VEC_ELT (condv, i) = cond;
12453 TREE_VEC_ELT (incrv, i) = incr;
12457 /* Like tsubst_copy for expressions, etc. but also does semantic
12461 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12462 bool integral_constant_expression_p)
12464 #define RECUR(NODE) \
12465 tsubst_expr ((NODE), args, complain, in_decl, \
12466 integral_constant_expression_p)
12470 if (t == NULL_TREE || t == error_mark_node)
12473 if (EXPR_HAS_LOCATION (t))
12474 input_location = EXPR_LOCATION (t);
12475 if (STATEMENT_CODE_P (TREE_CODE (t)))
12476 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12478 switch (TREE_CODE (t))
12480 case STATEMENT_LIST:
12482 tree_stmt_iterator i;
12483 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12484 RECUR (tsi_stmt (i));
12488 case CTOR_INITIALIZER:
12489 finish_mem_initializers (tsubst_initializer_list
12490 (TREE_OPERAND (t, 0), args));
12494 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12498 tmp = RECUR (EXPR_STMT_EXPR (t));
12499 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12500 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12502 finish_expr_stmt (tmp);
12506 do_using_directive (USING_STMT_NAMESPACE (t));
12511 tree decl, pattern_decl;
12514 pattern_decl = decl = DECL_EXPR_DECL (t);
12515 if (TREE_CODE (decl) == LABEL_DECL)
12516 finish_label_decl (DECL_NAME (decl));
12517 else if (TREE_CODE (decl) == USING_DECL)
12519 tree scope = USING_DECL_SCOPE (decl);
12520 tree name = DECL_NAME (decl);
12523 scope = tsubst (scope, args, complain, in_decl);
12524 decl = lookup_qualified_name (scope, name,
12525 /*is_type_p=*/false,
12526 /*complain=*/false);
12527 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12528 qualified_name_lookup_error (scope, name, decl, input_location);
12530 do_local_using_decl (decl, scope, name);
12534 init = DECL_INITIAL (decl);
12535 decl = tsubst (decl, args, complain, in_decl);
12536 if (decl != error_mark_node)
12538 /* By marking the declaration as instantiated, we avoid
12539 trying to instantiate it. Since instantiate_decl can't
12540 handle local variables, and since we've already done
12541 all that needs to be done, that's the right thing to
12543 if (TREE_CODE (decl) == VAR_DECL)
12544 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12545 if (TREE_CODE (decl) == VAR_DECL
12546 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12547 /* Anonymous aggregates are a special case. */
12548 finish_anon_union (decl);
12551 int const_init = false;
12552 maybe_push_decl (decl);
12553 if (TREE_CODE (decl) == VAR_DECL
12554 && DECL_PRETTY_FUNCTION_P (decl))
12556 /* For __PRETTY_FUNCTION__ we have to adjust the
12558 const char *const name
12559 = cxx_printable_name (current_function_decl, 2);
12560 init = cp_fname_init (name, &TREE_TYPE (decl));
12564 tree t = RECUR (init);
12568 /* If we had an initializer but it
12569 instantiated to nothing,
12570 value-initialize the object. This will
12571 only occur when the initializer was a
12572 pack expansion where the parameter packs
12573 used in that expansion were of length
12575 init = build_value_init (TREE_TYPE (decl),
12577 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12578 init = get_target_expr_sfinae (init, complain);
12584 if (TREE_CODE (decl) == VAR_DECL)
12585 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12587 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12592 /* A DECL_EXPR can also be used as an expression, in the condition
12593 clause of an if/for/while construct. */
12598 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12599 RECUR (FOR_INIT_STMT (t));
12600 finish_for_init_stmt (stmt);
12601 tmp = RECUR (FOR_COND (t));
12602 finish_for_cond (tmp, stmt);
12603 tmp = RECUR (FOR_EXPR (t));
12604 finish_for_expr (tmp, stmt);
12605 RECUR (FOR_BODY (t));
12606 finish_for_stmt (stmt);
12609 case RANGE_FOR_STMT:
12612 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12613 decl = RANGE_FOR_DECL (t);
12614 decl = tsubst (decl, args, complain, in_decl);
12615 maybe_push_decl (decl);
12616 expr = RECUR (RANGE_FOR_EXPR (t));
12617 stmt = cp_convert_range_for (stmt, decl, expr);
12618 RECUR (RANGE_FOR_BODY (t));
12619 finish_for_stmt (stmt);
12624 stmt = begin_while_stmt ();
12625 tmp = RECUR (WHILE_COND (t));
12626 finish_while_stmt_cond (tmp, stmt);
12627 RECUR (WHILE_BODY (t));
12628 finish_while_stmt (stmt);
12632 stmt = begin_do_stmt ();
12633 RECUR (DO_BODY (t));
12634 finish_do_body (stmt);
12635 tmp = RECUR (DO_COND (t));
12636 finish_do_stmt (tmp, stmt);
12640 stmt = begin_if_stmt ();
12641 tmp = RECUR (IF_COND (t));
12642 finish_if_stmt_cond (tmp, stmt);
12643 RECUR (THEN_CLAUSE (t));
12644 finish_then_clause (stmt);
12646 if (ELSE_CLAUSE (t))
12648 begin_else_clause (stmt);
12649 RECUR (ELSE_CLAUSE (t));
12650 finish_else_clause (stmt);
12653 finish_if_stmt (stmt);
12657 if (BIND_EXPR_BODY_BLOCK (t))
12658 stmt = begin_function_body ();
12660 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12661 ? BCS_TRY_BLOCK : 0);
12663 RECUR (BIND_EXPR_BODY (t));
12665 if (BIND_EXPR_BODY_BLOCK (t))
12666 finish_function_body (stmt);
12668 finish_compound_stmt (stmt);
12672 finish_break_stmt ();
12675 case CONTINUE_STMT:
12676 finish_continue_stmt ();
12680 stmt = begin_switch_stmt ();
12681 tmp = RECUR (SWITCH_STMT_COND (t));
12682 finish_switch_cond (tmp, stmt);
12683 RECUR (SWITCH_STMT_BODY (t));
12684 finish_switch_stmt (stmt);
12687 case CASE_LABEL_EXPR:
12688 finish_case_label (EXPR_LOCATION (t),
12689 RECUR (CASE_LOW (t)),
12690 RECUR (CASE_HIGH (t)));
12695 tree decl = LABEL_EXPR_LABEL (t);
12698 label = finish_label_stmt (DECL_NAME (decl));
12699 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
12700 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
12705 tmp = GOTO_DESTINATION (t);
12706 if (TREE_CODE (tmp) != LABEL_DECL)
12707 /* Computed goto's must be tsubst'd into. On the other hand,
12708 non-computed gotos must not be; the identifier in question
12709 will have no binding. */
12712 tmp = DECL_NAME (tmp);
12713 finish_goto_stmt (tmp);
12717 tmp = finish_asm_stmt
12718 (ASM_VOLATILE_P (t),
12719 RECUR (ASM_STRING (t)),
12720 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
12721 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
12722 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
12723 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
12725 tree asm_expr = tmp;
12726 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
12727 asm_expr = TREE_OPERAND (asm_expr, 0);
12728 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
12735 stmt = begin_try_block ();
12736 RECUR (TRY_STMTS (t));
12737 finish_cleanup_try_block (stmt);
12738 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
12742 tree compound_stmt = NULL_TREE;
12744 if (FN_TRY_BLOCK_P (t))
12745 stmt = begin_function_try_block (&compound_stmt);
12747 stmt = begin_try_block ();
12749 RECUR (TRY_STMTS (t));
12751 if (FN_TRY_BLOCK_P (t))
12752 finish_function_try_block (stmt);
12754 finish_try_block (stmt);
12756 RECUR (TRY_HANDLERS (t));
12757 if (FN_TRY_BLOCK_P (t))
12758 finish_function_handler_sequence (stmt, compound_stmt);
12760 finish_handler_sequence (stmt);
12766 tree decl = HANDLER_PARMS (t);
12770 decl = tsubst (decl, args, complain, in_decl);
12771 /* Prevent instantiate_decl from trying to instantiate
12772 this variable. We've already done all that needs to be
12774 if (decl != error_mark_node)
12775 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12777 stmt = begin_handler ();
12778 finish_handler_parms (decl, stmt);
12779 RECUR (HANDLER_BODY (t));
12780 finish_handler (stmt);
12785 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12788 case STATIC_ASSERT:
12791 tsubst_expr (STATIC_ASSERT_CONDITION (t),
12794 /*integral_constant_expression_p=*/true);
12795 finish_static_assert (condition,
12796 STATIC_ASSERT_MESSAGE (t),
12797 STATIC_ASSERT_SOURCE_LOCATION (t),
12798 /*member_p=*/false);
12803 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
12804 args, complain, in_decl);
12805 stmt = begin_omp_parallel ();
12806 RECUR (OMP_PARALLEL_BODY (t));
12807 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
12808 = OMP_PARALLEL_COMBINED (t);
12812 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
12813 args, complain, in_decl);
12814 stmt = begin_omp_task ();
12815 RECUR (OMP_TASK_BODY (t));
12816 finish_omp_task (tmp, stmt);
12821 tree clauses, body, pre_body;
12822 tree declv, initv, condv, incrv;
12825 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
12826 args, complain, in_decl);
12827 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12828 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12829 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12830 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
12832 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
12833 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
12834 &clauses, args, complain, in_decl,
12835 integral_constant_expression_p);
12837 stmt = begin_omp_structured_block ();
12839 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
12840 if (TREE_VEC_ELT (initv, i) == NULL
12841 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
12842 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
12843 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
12845 tree init = RECUR (TREE_VEC_ELT (initv, i));
12846 gcc_assert (init == TREE_VEC_ELT (declv, i));
12847 TREE_VEC_ELT (initv, i) = NULL_TREE;
12851 tree decl_expr = TREE_VEC_ELT (initv, i);
12852 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
12853 gcc_assert (init != NULL);
12854 TREE_VEC_ELT (initv, i) = RECUR (init);
12855 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
12857 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
12860 pre_body = push_stmt_list ();
12861 RECUR (OMP_FOR_PRE_BODY (t));
12862 pre_body = pop_stmt_list (pre_body);
12864 body = push_stmt_list ();
12865 RECUR (OMP_FOR_BODY (t));
12866 body = pop_stmt_list (body);
12868 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
12869 body, pre_body, clauses);
12871 add_stmt (finish_omp_structured_block (stmt));
12877 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
12878 stmt = push_stmt_list ();
12879 RECUR (OMP_BODY (t));
12880 stmt = pop_stmt_list (stmt);
12883 OMP_BODY (t) = stmt;
12884 OMP_CLAUSES (t) = tmp;
12892 stmt = push_stmt_list ();
12893 RECUR (OMP_BODY (t));
12894 stmt = pop_stmt_list (stmt);
12897 OMP_BODY (t) = stmt;
12902 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
12903 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
12905 tree op1 = TREE_OPERAND (t, 1);
12906 tree rhs1 = NULL_TREE;
12908 if (TREE_CODE (op1) == COMPOUND_EXPR)
12910 rhs1 = RECUR (TREE_OPERAND (op1, 0));
12911 op1 = TREE_OPERAND (op1, 1);
12913 lhs = RECUR (TREE_OPERAND (op1, 0));
12914 rhs = RECUR (TREE_OPERAND (op1, 1));
12915 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
12916 NULL_TREE, NULL_TREE, rhs1);
12920 tree op1 = TREE_OPERAND (t, 1);
12921 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
12922 tree rhs1 = NULL_TREE;
12923 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
12924 enum tree_code opcode = NOP_EXPR;
12925 if (code == OMP_ATOMIC_READ)
12927 v = RECUR (TREE_OPERAND (op1, 0));
12928 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
12930 else if (code == OMP_ATOMIC_CAPTURE_OLD
12931 || code == OMP_ATOMIC_CAPTURE_NEW)
12933 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
12934 v = RECUR (TREE_OPERAND (op1, 0));
12935 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
12936 if (TREE_CODE (op11) == COMPOUND_EXPR)
12938 rhs1 = RECUR (TREE_OPERAND (op11, 0));
12939 op11 = TREE_OPERAND (op11, 1);
12941 lhs = RECUR (TREE_OPERAND (op11, 0));
12942 rhs = RECUR (TREE_OPERAND (op11, 1));
12943 opcode = TREE_CODE (op11);
12948 lhs = RECUR (TREE_OPERAND (op1, 0));
12949 rhs = RECUR (TREE_OPERAND (op1, 1));
12951 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
12955 case EXPR_PACK_EXPANSION:
12956 error ("invalid use of pack expansion expression");
12957 return error_mark_node;
12959 case NONTYPE_ARGUMENT_PACK:
12960 error ("use %<...%> to expand argument pack");
12961 return error_mark_node;
12964 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
12966 return tsubst_copy_and_build (t, args, complain, in_decl,
12967 /*function_p=*/false,
12968 integral_constant_expression_p);
12975 /* T is a postfix-expression that is not being used in a function
12976 call. Return the substituted version of T. */
12979 tsubst_non_call_postfix_expression (tree t, tree args,
12980 tsubst_flags_t complain,
12983 if (TREE_CODE (t) == SCOPE_REF)
12984 t = tsubst_qualified_id (t, args, complain, in_decl,
12985 /*done=*/false, /*address_p=*/false);
12987 t = tsubst_copy_and_build (t, args, complain, in_decl,
12988 /*function_p=*/false,
12989 /*integral_constant_expression_p=*/false);
12994 /* Like tsubst but deals with expressions and performs semantic
12995 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
12998 tsubst_copy_and_build (tree t,
13000 tsubst_flags_t complain,
13003 bool integral_constant_expression_p)
13005 #define RECUR(NODE) \
13006 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13007 /*function_p=*/false, \
13008 integral_constant_expression_p)
13012 if (t == NULL_TREE || t == error_mark_node)
13015 switch (TREE_CODE (t))
13019 /* Fall through. */
13020 case IDENTIFIER_NODE:
13024 bool non_integral_constant_expression_p;
13025 const char *error_msg;
13027 if (IDENTIFIER_TYPENAME_P (t))
13029 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13030 t = mangle_conv_op_name_for_type (new_type);
13033 /* Look up the name. */
13034 decl = lookup_name (t);
13036 /* By convention, expressions use ERROR_MARK_NODE to indicate
13037 failure, not NULL_TREE. */
13038 if (decl == NULL_TREE)
13039 decl = error_mark_node;
13041 decl = finish_id_expression (t, decl, NULL_TREE,
13043 integral_constant_expression_p,
13044 /*allow_non_integral_constant_expression_p=*/false,
13045 &non_integral_constant_expression_p,
13046 /*template_p=*/false,
13048 /*address_p=*/false,
13049 /*template_arg_p=*/false,
13054 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13056 if (complain & tf_error)
13057 unqualified_name_lookup_error (decl);
13058 decl = error_mark_node;
13063 case TEMPLATE_ID_EXPR:
13066 tree templ = RECUR (TREE_OPERAND (t, 0));
13067 tree targs = TREE_OPERAND (t, 1);
13070 targs = tsubst_template_args (targs, args, complain, in_decl);
13072 if (TREE_CODE (templ) == COMPONENT_REF)
13074 object = TREE_OPERAND (templ, 0);
13075 templ = TREE_OPERAND (templ, 1);
13078 object = NULL_TREE;
13079 templ = lookup_template_function (templ, targs);
13082 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13083 object, templ, NULL_TREE);
13085 return baselink_for_fns (templ);
13090 tree r = RECUR (TREE_OPERAND (t, 0));
13092 if (REFERENCE_REF_P (t))
13094 /* A type conversion to reference type will be enclosed in
13095 such an indirect ref, but the substitution of the cast
13096 will have also added such an indirect ref. */
13097 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13098 r = convert_from_reference (r);
13101 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13107 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13108 RECUR (TREE_OPERAND (t, 0)));
13110 case IMPLICIT_CONV_EXPR:
13112 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13113 tree expr = RECUR (TREE_OPERAND (t, 0));
13114 int flags = LOOKUP_IMPLICIT;
13115 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13116 flags = LOOKUP_NORMAL;
13117 return perform_implicit_conversion_flags (type, expr, complain,
13124 tsubst (TREE_TYPE (t), args, complain, in_decl),
13125 RECUR (TREE_OPERAND (t, 0)));
13128 case REINTERPRET_CAST_EXPR:
13129 case CONST_CAST_EXPR:
13130 case DYNAMIC_CAST_EXPR:
13131 case STATIC_CAST_EXPR:
13136 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13137 if (integral_constant_expression_p
13138 && !cast_valid_in_integral_constant_expression_p (type))
13140 if (complain & tf_error)
13141 error ("a cast to a type other than an integral or "
13142 "enumeration type cannot appear in a constant-expression");
13143 return error_mark_node;
13146 op = RECUR (TREE_OPERAND (t, 0));
13148 switch (TREE_CODE (t))
13151 return build_functional_cast (type, op, complain);
13152 case REINTERPRET_CAST_EXPR:
13153 return build_reinterpret_cast (type, op, complain);
13154 case CONST_CAST_EXPR:
13155 return build_const_cast (type, op, complain);
13156 case DYNAMIC_CAST_EXPR:
13157 return build_dynamic_cast (type, op, complain);
13158 case STATIC_CAST_EXPR:
13159 return build_static_cast (type, op, complain);
13161 gcc_unreachable ();
13165 case POSTDECREMENT_EXPR:
13166 case POSTINCREMENT_EXPR:
13167 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13168 args, complain, in_decl);
13169 return build_x_unary_op (TREE_CODE (t), op1, complain);
13171 case PREDECREMENT_EXPR:
13172 case PREINCREMENT_EXPR:
13176 case TRUTH_NOT_EXPR:
13177 case UNARY_PLUS_EXPR: /* Unary + */
13178 case REALPART_EXPR:
13179 case IMAGPART_EXPR:
13180 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13184 op1 = TREE_OPERAND (t, 0);
13185 if (TREE_CODE (op1) == LABEL_DECL)
13186 return finish_label_address_expr (DECL_NAME (op1),
13187 EXPR_LOCATION (op1));
13188 if (TREE_CODE (op1) == SCOPE_REF)
13189 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13190 /*done=*/true, /*address_p=*/true);
13192 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13194 return build_x_unary_op (ADDR_EXPR, op1, complain);
13199 case TRUNC_DIV_EXPR:
13200 case CEIL_DIV_EXPR:
13201 case FLOOR_DIV_EXPR:
13202 case ROUND_DIV_EXPR:
13203 case EXACT_DIV_EXPR:
13207 case TRUNC_MOD_EXPR:
13208 case FLOOR_MOD_EXPR:
13209 case TRUTH_ANDIF_EXPR:
13210 case TRUTH_ORIF_EXPR:
13211 case TRUTH_AND_EXPR:
13212 case TRUTH_OR_EXPR:
13227 return build_x_binary_op
13229 RECUR (TREE_OPERAND (t, 0)),
13230 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13232 : TREE_CODE (TREE_OPERAND (t, 0))),
13233 RECUR (TREE_OPERAND (t, 1)),
13234 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13236 : TREE_CODE (TREE_OPERAND (t, 1))),
13241 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13242 /*address_p=*/false);
13244 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13245 args, complain, in_decl);
13246 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13249 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13250 return tsubst_copy (t, args, complain, in_decl);
13254 op1 = TREE_OPERAND (t, 0);
13257 /* When there are no ARGS, we are trying to evaluate a
13258 non-dependent expression from the parser. Trying to do
13259 the substitutions may not work. */
13261 op1 = TREE_TYPE (op1);
13265 ++cp_unevaluated_operand;
13266 ++c_inhibit_evaluation_warnings;
13267 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13268 /*function_p=*/false,
13269 /*integral_constant_expression_p=*/false);
13270 --cp_unevaluated_operand;
13271 --c_inhibit_evaluation_warnings;
13274 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13275 complain & tf_error);
13277 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13278 complain & tf_error);
13280 case AT_ENCODE_EXPR:
13282 op1 = TREE_OPERAND (t, 0);
13283 ++cp_unevaluated_operand;
13284 ++c_inhibit_evaluation_warnings;
13285 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13286 /*function_p=*/false,
13287 /*integral_constant_expression_p=*/false);
13288 --cp_unevaluated_operand;
13289 --c_inhibit_evaluation_warnings;
13290 return objc_build_encode_expr (op1);
13293 case NOEXCEPT_EXPR:
13294 op1 = TREE_OPERAND (t, 0);
13295 ++cp_unevaluated_operand;
13296 ++c_inhibit_evaluation_warnings;
13297 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13298 /*function_p=*/false,
13299 /*integral_constant_expression_p=*/false);
13300 --cp_unevaluated_operand;
13301 --c_inhibit_evaluation_warnings;
13302 return finish_noexcept_expr (op1, complain);
13306 tree r = build_x_modify_expr
13307 (RECUR (TREE_OPERAND (t, 0)),
13308 TREE_CODE (TREE_OPERAND (t, 1)),
13309 RECUR (TREE_OPERAND (t, 2)),
13311 /* TREE_NO_WARNING must be set if either the expression was
13312 parenthesized or it uses an operator such as >>= rather
13313 than plain assignment. In the former case, it was already
13314 set and must be copied. In the latter case,
13315 build_x_modify_expr sets it and it must not be reset
13317 if (TREE_NO_WARNING (t))
13318 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13323 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13324 args, complain, in_decl);
13325 /* Remember that there was a reference to this entity. */
13328 return build_x_arrow (op1);
13332 tree placement = RECUR (TREE_OPERAND (t, 0));
13333 tree init = RECUR (TREE_OPERAND (t, 3));
13334 VEC(tree,gc) *placement_vec;
13335 VEC(tree,gc) *init_vec;
13338 if (placement == NULL_TREE)
13339 placement_vec = NULL;
13342 placement_vec = make_tree_vector ();
13343 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13344 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13347 /* If there was an initializer in the original tree, but it
13348 instantiated to an empty list, then we should pass a
13349 non-NULL empty vector to tell build_new that it was an
13350 empty initializer() rather than no initializer. This can
13351 only happen when the initializer is a pack expansion whose
13352 parameter packs are of length zero. */
13353 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13357 init_vec = make_tree_vector ();
13358 if (init == void_zero_node)
13359 gcc_assert (init_vec != NULL);
13362 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13363 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13367 ret = build_new (&placement_vec,
13368 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13369 RECUR (TREE_OPERAND (t, 2)),
13371 NEW_EXPR_USE_GLOBAL (t),
13374 if (placement_vec != NULL)
13375 release_tree_vector (placement_vec);
13376 if (init_vec != NULL)
13377 release_tree_vector (init_vec);
13383 return delete_sanity
13384 (RECUR (TREE_OPERAND (t, 0)),
13385 RECUR (TREE_OPERAND (t, 1)),
13386 DELETE_EXPR_USE_VEC (t),
13387 DELETE_EXPR_USE_GLOBAL (t),
13390 case COMPOUND_EXPR:
13391 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13392 RECUR (TREE_OPERAND (t, 1)),
13398 VEC(tree,gc) *call_args;
13399 unsigned int nargs, i;
13404 function = CALL_EXPR_FN (t);
13405 /* When we parsed the expression, we determined whether or
13406 not Koenig lookup should be performed. */
13407 koenig_p = KOENIG_LOOKUP_P (t);
13408 if (TREE_CODE (function) == SCOPE_REF)
13410 qualified_p = true;
13411 function = tsubst_qualified_id (function, args, complain, in_decl,
13413 /*address_p=*/false);
13415 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13417 /* Do nothing; calling tsubst_copy_and_build on an identifier
13418 would incorrectly perform unqualified lookup again.
13420 Note that we can also have an IDENTIFIER_NODE if the earlier
13421 unqualified lookup found a member function; in that case
13422 koenig_p will be false and we do want to do the lookup
13423 again to find the instantiated member function.
13425 FIXME but doing that causes c++/15272, so we need to stop
13426 using IDENTIFIER_NODE in that situation. */
13427 qualified_p = false;
13431 if (TREE_CODE (function) == COMPONENT_REF)
13433 tree op = TREE_OPERAND (function, 1);
13435 qualified_p = (TREE_CODE (op) == SCOPE_REF
13436 || (BASELINK_P (op)
13437 && BASELINK_QUALIFIED_P (op)));
13440 qualified_p = false;
13442 function = tsubst_copy_and_build (function, args, complain,
13445 integral_constant_expression_p);
13447 if (BASELINK_P (function))
13448 qualified_p = true;
13451 nargs = call_expr_nargs (t);
13452 call_args = make_tree_vector ();
13453 for (i = 0; i < nargs; ++i)
13455 tree arg = CALL_EXPR_ARG (t, i);
13457 if (!PACK_EXPANSION_P (arg))
13458 VEC_safe_push (tree, gc, call_args,
13459 RECUR (CALL_EXPR_ARG (t, i)));
13462 /* Expand the pack expansion and push each entry onto
13464 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13465 if (TREE_CODE (arg) == TREE_VEC)
13467 unsigned int len, j;
13469 len = TREE_VEC_LENGTH (arg);
13470 for (j = 0; j < len; ++j)
13472 tree value = TREE_VEC_ELT (arg, j);
13473 if (value != NULL_TREE)
13474 value = convert_from_reference (value);
13475 VEC_safe_push (tree, gc, call_args, value);
13480 /* A partial substitution. Add one entry. */
13481 VEC_safe_push (tree, gc, call_args, arg);
13486 /* We do not perform argument-dependent lookup if normal
13487 lookup finds a non-function, in accordance with the
13488 expected resolution of DR 218. */
13490 && ((is_overloaded_fn (function)
13491 /* If lookup found a member function, the Koenig lookup is
13492 not appropriate, even if an unqualified-name was used
13493 to denote the function. */
13494 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13495 || TREE_CODE (function) == IDENTIFIER_NODE)
13496 /* Only do this when substitution turns a dependent call
13497 into a non-dependent call. */
13498 && type_dependent_expression_p_push (t)
13499 && !any_type_dependent_arguments_p (call_args))
13500 function = perform_koenig_lookup (function, call_args, false,
13503 if (TREE_CODE (function) == IDENTIFIER_NODE
13504 && !any_type_dependent_arguments_p (call_args))
13506 if (koenig_p && (complain & tf_warning_or_error))
13508 /* For backwards compatibility and good diagnostics, try
13509 the unqualified lookup again if we aren't in SFINAE
13511 tree unq = (tsubst_copy_and_build
13512 (function, args, complain, in_decl, true,
13513 integral_constant_expression_p));
13514 if (unq == error_mark_node)
13515 return error_mark_node;
13517 if (unq != function)
13520 if (TREE_CODE (fn) == COMPONENT_REF)
13521 fn = TREE_OPERAND (fn, 1);
13522 if (is_overloaded_fn (fn))
13523 fn = get_first_fn (fn);
13524 permerror (EXPR_LOC_OR_HERE (t),
13525 "%qD was not declared in this scope, "
13526 "and no declarations were found by "
13527 "argument-dependent lookup at the point "
13528 "of instantiation", function);
13529 if (DECL_CLASS_SCOPE_P (fn))
13531 inform (EXPR_LOC_OR_HERE (t),
13532 "declarations in dependent base %qT are "
13533 "not found by unqualified lookup",
13534 DECL_CLASS_CONTEXT (fn));
13535 if (current_class_ptr)
13536 inform (EXPR_LOC_OR_HERE (t),
13537 "use %<this->%D%> instead", function);
13539 inform (EXPR_LOC_OR_HERE (t),
13540 "use %<%T::%D%> instead",
13541 current_class_name, function);
13544 inform (0, "%q+D declared here, later in the "
13545 "translation unit", fn);
13549 if (TREE_CODE (function) == IDENTIFIER_NODE)
13551 unqualified_name_lookup_error (function);
13552 release_tree_vector (call_args);
13553 return error_mark_node;
13557 /* Remember that there was a reference to this entity. */
13558 if (DECL_P (function))
13559 mark_used (function);
13561 if (TREE_CODE (function) == OFFSET_REF)
13562 ret = build_offset_ref_call_from_tree (function, &call_args);
13563 else if (TREE_CODE (function) == COMPONENT_REF)
13565 tree instance = TREE_OPERAND (function, 0);
13566 tree fn = TREE_OPERAND (function, 1);
13568 if (processing_template_decl
13569 && (type_dependent_expression_p (instance)
13570 || (!BASELINK_P (fn)
13571 && TREE_CODE (fn) != FIELD_DECL)
13572 || type_dependent_expression_p (fn)
13573 || any_type_dependent_arguments_p (call_args)))
13574 ret = build_nt_call_vec (function, call_args);
13575 else if (!BASELINK_P (fn))
13576 ret = finish_call_expr (function, &call_args,
13577 /*disallow_virtual=*/false,
13578 /*koenig_p=*/false,
13581 ret = (build_new_method_call
13583 &call_args, NULL_TREE,
13584 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13589 ret = finish_call_expr (function, &call_args,
13590 /*disallow_virtual=*/qualified_p,
13594 release_tree_vector (call_args);
13600 return build_x_conditional_expr
13601 (RECUR (TREE_OPERAND (t, 0)),
13602 RECUR (TREE_OPERAND (t, 1)),
13603 RECUR (TREE_OPERAND (t, 2)),
13606 case PSEUDO_DTOR_EXPR:
13607 return finish_pseudo_destructor_expr
13608 (RECUR (TREE_OPERAND (t, 0)),
13609 RECUR (TREE_OPERAND (t, 1)),
13610 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13614 tree purpose, value, chain;
13616 if (t == void_list_node)
13619 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13620 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13622 /* We have pack expansions, so expand those and
13623 create a new list out of it. */
13624 tree purposevec = NULL_TREE;
13625 tree valuevec = NULL_TREE;
13629 /* Expand the argument expressions. */
13630 if (TREE_PURPOSE (t))
13631 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13632 complain, in_decl);
13633 if (TREE_VALUE (t))
13634 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13635 complain, in_decl);
13637 /* Build the rest of the list. */
13638 chain = TREE_CHAIN (t);
13639 if (chain && chain != void_type_node)
13640 chain = RECUR (chain);
13642 /* Determine the number of arguments. */
13643 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13645 len = TREE_VEC_LENGTH (purposevec);
13646 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13648 else if (TREE_CODE (valuevec) == TREE_VEC)
13649 len = TREE_VEC_LENGTH (valuevec);
13652 /* Since we only performed a partial substitution into
13653 the argument pack, we only return a single list
13655 if (purposevec == TREE_PURPOSE (t)
13656 && valuevec == TREE_VALUE (t)
13657 && chain == TREE_CHAIN (t))
13660 return tree_cons (purposevec, valuevec, chain);
13663 /* Convert the argument vectors into a TREE_LIST */
13667 /* Grab the Ith values. */
13669 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
13672 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
13675 /* Build the list (backwards). */
13676 chain = tree_cons (purpose, value, chain);
13682 purpose = TREE_PURPOSE (t);
13684 purpose = RECUR (purpose);
13685 value = TREE_VALUE (t);
13687 value = RECUR (value);
13688 chain = TREE_CHAIN (t);
13689 if (chain && chain != void_type_node)
13690 chain = RECUR (chain);
13691 if (purpose == TREE_PURPOSE (t)
13692 && value == TREE_VALUE (t)
13693 && chain == TREE_CHAIN (t))
13695 return tree_cons (purpose, value, chain);
13698 case COMPONENT_REF:
13704 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13705 args, complain, in_decl);
13706 /* Remember that there was a reference to this entity. */
13707 if (DECL_P (object))
13708 mark_used (object);
13709 object_type = TREE_TYPE (object);
13711 member = TREE_OPERAND (t, 1);
13712 if (BASELINK_P (member))
13713 member = tsubst_baselink (member,
13714 non_reference (TREE_TYPE (object)),
13715 args, complain, in_decl);
13717 member = tsubst_copy (member, args, complain, in_decl);
13718 if (member == error_mark_node)
13719 return error_mark_node;
13721 if (object_type && !CLASS_TYPE_P (object_type))
13723 if (SCALAR_TYPE_P (object_type))
13725 tree s = NULL_TREE;
13726 tree dtor = member;
13728 if (TREE_CODE (dtor) == SCOPE_REF)
13730 s = TREE_OPERAND (dtor, 0);
13731 dtor = TREE_OPERAND (dtor, 1);
13733 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
13735 dtor = TREE_OPERAND (dtor, 0);
13737 return finish_pseudo_destructor_expr (object, s, dtor);
13741 else if (TREE_CODE (member) == SCOPE_REF
13742 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
13747 /* Lookup the template functions now that we know what the
13749 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
13750 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
13751 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
13752 /*is_type_p=*/false,
13753 /*complain=*/false);
13754 if (BASELINK_P (member))
13756 BASELINK_FUNCTIONS (member)
13757 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
13759 member = (adjust_result_of_qualified_name_lookup
13760 (member, BINFO_TYPE (BASELINK_BINFO (member)),
13765 qualified_name_lookup_error (object_type, tmpl, member,
13767 return error_mark_node;
13770 else if (TREE_CODE (member) == SCOPE_REF
13771 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
13772 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
13774 if (complain & tf_error)
13776 if (TYPE_P (TREE_OPERAND (member, 0)))
13777 error ("%qT is not a class or namespace",
13778 TREE_OPERAND (member, 0));
13780 error ("%qD is not a class or namespace",
13781 TREE_OPERAND (member, 0));
13783 return error_mark_node;
13785 else if (TREE_CODE (member) == FIELD_DECL)
13786 return finish_non_static_data_member (member, object, NULL_TREE);
13788 return finish_class_member_access_expr (object, member,
13789 /*template_p=*/false,
13795 (RECUR (TREE_OPERAND (t, 0)));
13799 VEC(constructor_elt,gc) *n;
13800 constructor_elt *ce;
13801 unsigned HOST_WIDE_INT idx;
13802 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13803 bool process_index_p;
13805 bool need_copy_p = false;
13808 if (type == error_mark_node)
13809 return error_mark_node;
13811 /* digest_init will do the wrong thing if we let it. */
13812 if (type && TYPE_PTRMEMFUNC_P (type))
13815 /* We do not want to process the index of aggregate
13816 initializers as they are identifier nodes which will be
13817 looked up by digest_init. */
13818 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
13820 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
13821 newlen = VEC_length (constructor_elt, n);
13822 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
13824 if (ce->index && process_index_p)
13825 ce->index = RECUR (ce->index);
13827 if (PACK_EXPANSION_P (ce->value))
13829 /* Substitute into the pack expansion. */
13830 ce->value = tsubst_pack_expansion (ce->value, args, complain,
13833 if (ce->value == error_mark_node
13834 || PACK_EXPANSION_P (ce->value))
13836 else if (TREE_VEC_LENGTH (ce->value) == 1)
13837 /* Just move the argument into place. */
13838 ce->value = TREE_VEC_ELT (ce->value, 0);
13841 /* Update the length of the final CONSTRUCTOR
13842 arguments vector, and note that we will need to
13844 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
13845 need_copy_p = true;
13849 ce->value = RECUR (ce->value);
13854 VEC(constructor_elt,gc) *old_n = n;
13856 n = VEC_alloc (constructor_elt, gc, newlen);
13857 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
13859 if (TREE_CODE (ce->value) == TREE_VEC)
13861 int i, len = TREE_VEC_LENGTH (ce->value);
13862 for (i = 0; i < len; ++i)
13863 CONSTRUCTOR_APPEND_ELT (n, 0,
13864 TREE_VEC_ELT (ce->value, i));
13867 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
13871 r = build_constructor (init_list_type_node, n);
13872 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
13874 if (TREE_HAS_CONSTRUCTOR (t))
13875 return finish_compound_literal (type, r, complain);
13877 TREE_TYPE (r) = type;
13883 tree operand_0 = TREE_OPERAND (t, 0);
13884 if (TYPE_P (operand_0))
13886 operand_0 = tsubst (operand_0, args, complain, in_decl);
13887 return get_typeid (operand_0);
13891 operand_0 = RECUR (operand_0);
13892 return build_typeid (operand_0);
13903 tree r = tsubst_copy (t, args, complain, in_decl);
13905 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
13906 /* If the original type was a reference, we'll be wrapped in
13907 the appropriate INDIRECT_REF. */
13908 r = convert_from_reference (r);
13913 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
13914 tsubst (TREE_TYPE (t), args, complain, in_decl));
13916 case OFFSETOF_EXPR:
13917 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
13921 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
13922 complain, in_decl);
13924 tree type2 = TRAIT_EXPR_TYPE2 (t);
13926 type2 = tsubst_copy (type2, args, complain, in_decl);
13928 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
13933 tree old_stmt_expr = cur_stmt_expr;
13934 tree stmt_expr = begin_stmt_expr ();
13936 cur_stmt_expr = stmt_expr;
13937 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
13938 integral_constant_expression_p);
13939 stmt_expr = finish_stmt_expr (stmt_expr, false);
13940 cur_stmt_expr = old_stmt_expr;
13942 /* If the resulting list of expression statement is empty,
13943 fold it further into void_zero_node. */
13944 if (empty_expr_stmt_p (stmt_expr))
13945 stmt_expr = void_zero_node;
13951 t = tsubst_copy (t, args, complain, in_decl);
13952 /* As in finish_id_expression, we resolve enumeration constants
13953 to their underlying values. */
13954 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
13956 used_types_insert (TREE_TYPE (t));
13957 return DECL_INITIAL (t);
13963 tree r = build_lambda_expr ();
13965 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
13966 LAMBDA_EXPR_CLOSURE (r) = type;
13967 CLASSTYPE_LAMBDA_EXPR (type) = r;
13969 LAMBDA_EXPR_LOCATION (r)
13970 = LAMBDA_EXPR_LOCATION (t);
13971 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
13972 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
13973 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
13974 LAMBDA_EXPR_DISCRIMINATOR (r)
13975 = (LAMBDA_EXPR_DISCRIMINATOR (t));
13976 LAMBDA_EXPR_EXTRA_SCOPE (r)
13977 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
13978 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
13980 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
13981 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
13984 LAMBDA_EXPR_RETURN_TYPE (r)
13985 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
13987 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
13988 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
13990 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
13991 determine_visibility (TYPE_NAME (type));
13992 /* Now that we know visibility, instantiate the type so we have a
13993 declaration of the op() for later calls to lambda_function. */
13994 complete_type (type);
13996 /* The capture list refers to closure members, so this needs to
13997 wait until after we finish instantiating the type. */
13998 LAMBDA_EXPR_CAPTURE_LIST (r)
13999 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14001 return build_lambda_object (r);
14005 /* We can get here for a constant initializer of non-dependent type.
14006 FIXME stop folding in cp_parser_initializer_clause. */
14007 gcc_assert (TREE_CONSTANT (t));
14009 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14010 TREE_CONSTANT (r) = true;
14015 /* Handle Objective-C++ constructs, if appropriate. */
14018 = objcp_tsubst_copy_and_build (t, args, complain,
14019 in_decl, /*function_p=*/false);
14023 return tsubst_copy (t, args, complain, in_decl);
14029 /* Verify that the instantiated ARGS are valid. For type arguments,
14030 make sure that the type's linkage is ok. For non-type arguments,
14031 make sure they are constants if they are integral or enumerations.
14032 Emit an error under control of COMPLAIN, and return TRUE on error. */
14035 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14037 if (ARGUMENT_PACK_P (t))
14039 tree vec = ARGUMENT_PACK_ARGS (t);
14040 int len = TREE_VEC_LENGTH (vec);
14041 bool result = false;
14044 for (i = 0; i < len; ++i)
14045 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14049 else if (TYPE_P (t))
14051 /* [basic.link]: A name with no linkage (notably, the name
14052 of a class or enumeration declared in a local scope)
14053 shall not be used to declare an entity with linkage.
14054 This implies that names with no linkage cannot be used as
14057 DR 757 relaxes this restriction for C++0x. */
14058 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14059 : no_linkage_check (t, /*relaxed_p=*/false));
14063 /* DR 488 makes use of a type with no linkage cause
14064 type deduction to fail. */
14065 if (complain & tf_error)
14067 if (TYPE_ANONYMOUS_P (nt))
14068 error ("%qT is/uses anonymous type", t);
14070 error ("template argument for %qD uses local type %qT",
14075 /* In order to avoid all sorts of complications, we do not
14076 allow variably-modified types as template arguments. */
14077 else if (variably_modified_type_p (t, NULL_TREE))
14079 if (complain & tf_error)
14080 error ("%qT is a variably modified type", t);
14084 /* A non-type argument of integral or enumerated type must be a
14086 else if (TREE_TYPE (t)
14087 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14088 && !TREE_CONSTANT (t))
14090 if (complain & tf_error)
14091 error ("integral expression %qE is not constant", t);
14098 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14100 int ix, len = DECL_NTPARMS (tmpl);
14101 bool result = false;
14103 for (ix = 0; ix != len; ix++)
14105 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14108 if (result && (complain & tf_error))
14109 error (" trying to instantiate %qD", tmpl);
14113 /* In C++0x, it's possible to have a function template whose type depends
14114 on itself recursively. This is most obvious with decltype, but can also
14115 occur with enumeration scope (c++/48969). So we need to catch infinite
14116 recursion and reject the substitution at deduction time; this function
14117 will return error_mark_node for any repeated substitution.
14119 This also catches excessive recursion such as when f<N> depends on
14120 f<N-1> across all integers, and returns error_mark_node for all the
14121 substitutions back up to the initial one.
14123 This is, of course, not reentrant. */
14126 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14128 static bool excessive_deduction_depth;
14129 static int deduction_depth;
14130 struct pending_template *old_last_pend = last_pending_template;
14131 struct tinst_level *old_error_tinst = last_error_tinst_level;
14133 tree fntype = TREE_TYPE (fn);
14137 if (excessive_deduction_depth)
14138 return error_mark_node;
14140 tinst = build_tree_list (fn, targs);
14141 if (!push_tinst_level (tinst))
14143 excessive_deduction_depth = true;
14145 return error_mark_node;
14148 input_location = DECL_SOURCE_LOCATION (fn);
14150 push_deduction_access_scope (fn);
14151 r = tsubst (fntype, targs, complain, NULL_TREE);
14152 pop_deduction_access_scope (fn);
14155 if (excessive_deduction_depth)
14157 r = error_mark_node;
14158 if (deduction_depth == 0)
14159 /* Reset once we're all the way out. */
14160 excessive_deduction_depth = false;
14163 pop_tinst_level ();
14164 /* We can't free this if a pending_template entry or last_error_tinst_level
14165 is pointing at it. */
14166 if (last_pending_template == old_last_pend
14167 && last_error_tinst_level == old_error_tinst)
14172 /* Instantiate the indicated variable or function template TMPL with
14173 the template arguments in TARG_PTR. */
14176 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14178 tree targ_ptr = orig_args;
14182 HOST_WIDE_INT saved_processing_template_decl;
14184 if (tmpl == error_mark_node)
14185 return error_mark_node;
14187 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14189 /* If this function is a clone, handle it specially. */
14190 if (DECL_CLONED_FUNCTION_P (tmpl))
14195 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14196 DECL_CLONED_FUNCTION. */
14197 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14198 targ_ptr, complain);
14199 if (spec == error_mark_node)
14200 return error_mark_node;
14202 /* Look for the clone. */
14203 FOR_EACH_CLONE (clone, spec)
14204 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14206 /* We should always have found the clone by now. */
14207 gcc_unreachable ();
14211 /* Check to see if we already have this specialization. */
14212 gen_tmpl = most_general_template (tmpl);
14213 if (tmpl != gen_tmpl)
14214 /* The TMPL is a partial instantiation. To get a full set of
14215 arguments we must add the arguments used to perform the
14216 partial instantiation. */
14217 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14220 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14221 but it doesn't seem to be on the hot path. */
14222 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14224 gcc_assert (tmpl == gen_tmpl
14225 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14227 || fndecl == NULL_TREE);
14229 if (spec != NULL_TREE)
14232 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14234 return error_mark_node;
14236 /* We are building a FUNCTION_DECL, during which the access of its
14237 parameters and return types have to be checked. However this
14238 FUNCTION_DECL which is the desired context for access checking
14239 is not built yet. We solve this chicken-and-egg problem by
14240 deferring all checks until we have the FUNCTION_DECL. */
14241 push_deferring_access_checks (dk_deferred);
14243 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
14244 (because, for example, we have encountered a non-dependent
14245 function call in the body of a template function and must now
14246 determine which of several overloaded functions will be called),
14247 within the instantiation itself we are not processing a
14249 saved_processing_template_decl = processing_template_decl;
14250 processing_template_decl = 0;
14251 /* Substitute template parameters to obtain the specialization. */
14252 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14253 targ_ptr, complain, gen_tmpl);
14254 processing_template_decl = saved_processing_template_decl;
14255 if (fndecl == error_mark_node)
14256 return error_mark_node;
14258 /* Now we know the specialization, compute access previously
14260 push_access_scope (fndecl);
14262 /* Some typedefs referenced from within the template code need to be access
14263 checked at template instantiation time, i.e now. These types were
14264 added to the template at parsing time. Let's get those and perfom
14265 the acces checks then. */
14266 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14267 perform_deferred_access_checks ();
14268 pop_access_scope (fndecl);
14269 pop_deferring_access_checks ();
14271 /* The DECL_TI_TEMPLATE should always be the immediate parent
14272 template, not the most general template. */
14273 DECL_TI_TEMPLATE (fndecl) = tmpl;
14275 /* If we've just instantiated the main entry point for a function,
14276 instantiate all the alternate entry points as well. We do this
14277 by cloning the instantiation of the main entry point, not by
14278 instantiating the template clones. */
14279 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14280 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14285 /* Wrapper for instantiate_template_1. */
14288 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14291 timevar_push (TV_TEMPLATE_INST);
14292 ret = instantiate_template_1 (tmpl, orig_args, complain);
14293 timevar_pop (TV_TEMPLATE_INST);
14297 /* We're going to do deduction substitution on the type of TMPL, a function
14298 template. In C++11 mode, push into that access scope. In C++03 mode,
14299 disable access checking. */
14302 push_deduction_access_scope (tree tmpl)
14304 if (cxx_dialect >= cxx0x)
14306 int ptd = processing_template_decl;
14307 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14308 /* Preserve processing_template_decl across push_to_top_level. */
14309 if (ptd && !processing_template_decl)
14310 ++processing_template_decl;
14313 push_deferring_access_checks (dk_no_check);
14316 /* And pop back out. */
14319 pop_deduction_access_scope (tree tmpl)
14321 if (cxx_dialect >= cxx0x)
14322 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14324 pop_deferring_access_checks ();
14327 /* PARM is a template parameter pack for FN. Returns true iff
14328 PARM is used in a deducible way in the argument list of FN. */
14331 pack_deducible_p (tree parm, tree fn)
14333 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14334 for (; t; t = TREE_CHAIN (t))
14336 tree type = TREE_VALUE (t);
14338 if (!PACK_EXPANSION_P (type))
14340 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14341 packs; packs = TREE_CHAIN (packs))
14342 if (TREE_VALUE (packs) == parm)
14344 /* The template parameter pack is used in a function parameter
14345 pack. If this is the end of the parameter list, the
14346 template parameter pack is deducible. */
14347 if (TREE_CHAIN (t) == void_list_node)
14350 /* Otherwise, not. Well, it could be deduced from
14351 a non-pack parameter, but doing so would end up with
14352 a deduction mismatch, so don't bother. */
14356 /* The template parameter pack isn't used in any function parameter
14357 packs, but it might be used deeper, e.g. tuple<Args...>. */
14361 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14362 NARGS elements of the arguments that are being used when calling
14363 it. TARGS is a vector into which the deduced template arguments
14366 Return zero for success, 2 for an incomplete match that doesn't resolve
14367 all the types, and 1 for complete failure. An error message will be
14368 printed only for an incomplete match.
14370 If FN is a conversion operator, or we are trying to produce a specific
14371 specialization, RETURN_TYPE is the return type desired.
14373 The EXPLICIT_TARGS are explicit template arguments provided via a
14376 The parameter STRICT is one of:
14379 We are deducing arguments for a function call, as in
14380 [temp.deduct.call].
14383 We are deducing arguments for a conversion function, as in
14384 [temp.deduct.conv].
14387 We are deducing arguments when doing an explicit instantiation
14388 as in [temp.explicit], when determining an explicit specialization
14389 as in [temp.expl.spec], or when taking the address of a function
14390 template, as in [temp.deduct.funcaddr]. */
14393 fn_type_unification (tree fn,
14394 tree explicit_targs,
14397 unsigned int nargs,
14399 unification_kind_t strict,
14407 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14409 fntype = TREE_TYPE (fn);
14410 if (explicit_targs)
14414 The specified template arguments must match the template
14415 parameters in kind (i.e., type, nontype, template), and there
14416 must not be more arguments than there are parameters;
14417 otherwise type deduction fails.
14419 Nontype arguments must match the types of the corresponding
14420 nontype template parameters, or must be convertible to the
14421 types of the corresponding nontype parameters as specified in
14422 _temp.arg.nontype_, otherwise type deduction fails.
14424 All references in the function type of the function template
14425 to the corresponding template parameters are replaced by the
14426 specified template argument values. If a substitution in a
14427 template parameter or in the function type of the function
14428 template results in an invalid type, type deduction fails. */
14429 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14430 int i, len = TREE_VEC_LENGTH (tparms);
14431 tree converted_args;
14432 bool incomplete = false;
14434 if (explicit_targs == error_mark_node)
14435 return unify_invalid (explain_p);
14438 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14440 ? tf_warning_or_error
14442 /*require_all_args=*/false,
14443 /*use_default_args=*/false));
14444 if (converted_args == error_mark_node)
14447 /* Substitute the explicit args into the function type. This is
14448 necessary so that, for instance, explicitly declared function
14449 arguments can match null pointed constants. If we were given
14450 an incomplete set of explicit args, we must not do semantic
14451 processing during substitution as we could create partial
14453 for (i = 0; i < len; i++)
14455 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14456 bool parameter_pack = false;
14457 tree targ = TREE_VEC_ELT (converted_args, i);
14459 /* Dig out the actual parm. */
14460 if (TREE_CODE (parm) == TYPE_DECL
14461 || TREE_CODE (parm) == TEMPLATE_DECL)
14463 parm = TREE_TYPE (parm);
14464 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14466 else if (TREE_CODE (parm) == PARM_DECL)
14468 parm = DECL_INITIAL (parm);
14469 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14472 if (!parameter_pack && targ == NULL_TREE)
14473 /* No explicit argument for this template parameter. */
14476 if (parameter_pack && pack_deducible_p (parm, fn))
14478 /* Mark the argument pack as "incomplete". We could
14479 still deduce more arguments during unification.
14480 We remove this mark in type_unification_real. */
14483 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14484 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14485 = ARGUMENT_PACK_ARGS (targ);
14488 /* We have some incomplete argument packs. */
14493 processing_template_decl += incomplete;
14494 fntype = deduction_tsubst_fntype (fn, converted_args,
14496 ? tf_warning_or_error
14498 processing_template_decl -= incomplete;
14500 if (fntype == error_mark_node)
14503 /* Place the explicitly specified arguments in TARGS. */
14504 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14505 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14508 /* Never do unification on the 'this' parameter. */
14509 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14515 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14516 new_args = XALLOCAVEC (tree, nargs + 1);
14517 new_args[0] = return_type;
14518 memcpy (new_args + 1, args, nargs * sizeof (tree));
14523 /* We allow incomplete unification without an error message here
14524 because the standard doesn't seem to explicitly prohibit it. Our
14525 callers must be ready to deal with unification failures in any
14527 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14528 targs, parms, args, nargs, /*subr=*/0,
14529 strict, flags, explain_p);
14531 /* Now that we have bindings for all of the template arguments,
14532 ensure that the arguments deduced for the template template
14533 parameters have compatible template parameter lists. We cannot
14534 check this property before we have deduced all template
14535 arguments, because the template parameter types of a template
14536 template parameter might depend on prior template parameters
14537 deduced after the template template parameter. The following
14538 ill-formed example illustrates this issue:
14540 template<typename T, template<T> class C> void f(C<5>, T);
14542 template<int N> struct X {};
14545 f(X<5>(), 5l); // error: template argument deduction fails
14548 The template parameter list of 'C' depends on the template type
14549 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14550 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14551 time that we deduce 'C'. */
14553 && !template_template_parm_bindings_ok_p
14554 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14555 return unify_inconsistent_template_template_parameters (explain_p);
14558 /* All is well so far. Now, check:
14562 When all template arguments have been deduced, all uses of
14563 template parameters in nondeduced contexts are replaced with
14564 the corresponding deduced argument values. If the
14565 substitution results in an invalid type, as described above,
14566 type deduction fails. */
14568 tree substed = deduction_tsubst_fntype (fn, targs,
14570 ? tf_warning_or_error
14572 if (substed == error_mark_node)
14575 /* If we're looking for an exact match, check that what we got
14576 is indeed an exact match. It might not be if some template
14577 parameters are used in non-deduced contexts. */
14578 if (strict == DEDUCE_EXACT)
14583 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14585 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14586 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14587 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14588 return unify_type_mismatch (explain_p, args[i],
14589 TREE_VALUE (sarg));
14596 /* Adjust types before performing type deduction, as described in
14597 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14598 sections are symmetric. PARM is the type of a function parameter
14599 or the return type of the conversion function. ARG is the type of
14600 the argument passed to the call, or the type of the value
14601 initialized with the result of the conversion function.
14602 ARG_EXPR is the original argument expression, which may be null. */
14605 maybe_adjust_types_for_deduction (unification_kind_t strict,
14619 /* Swap PARM and ARG throughout the remainder of this
14620 function; the handling is precisely symmetric since PARM
14621 will initialize ARG rather than vice versa. */
14629 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14630 too, but here handle it by stripping the reference from PARM
14631 rather than by adding it to ARG. */
14632 if (TREE_CODE (*parm) == REFERENCE_TYPE
14633 && TYPE_REF_IS_RVALUE (*parm)
14634 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14635 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14636 && TREE_CODE (*arg) == REFERENCE_TYPE
14637 && !TYPE_REF_IS_RVALUE (*arg))
14638 *parm = TREE_TYPE (*parm);
14639 /* Nothing else to do in this case. */
14643 gcc_unreachable ();
14646 if (TREE_CODE (*parm) != REFERENCE_TYPE)
14648 /* [temp.deduct.call]
14650 If P is not a reference type:
14652 --If A is an array type, the pointer type produced by the
14653 array-to-pointer standard conversion (_conv.array_) is
14654 used in place of A for type deduction; otherwise,
14656 --If A is a function type, the pointer type produced by
14657 the function-to-pointer standard conversion
14658 (_conv.func_) is used in place of A for type deduction;
14661 --If A is a cv-qualified type, the top level
14662 cv-qualifiers of A's type are ignored for type
14664 if (TREE_CODE (*arg) == ARRAY_TYPE)
14665 *arg = build_pointer_type (TREE_TYPE (*arg));
14666 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
14667 *arg = build_pointer_type (*arg);
14669 *arg = TYPE_MAIN_VARIANT (*arg);
14672 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
14673 of the form T&&, where T is a template parameter, and the argument
14674 is an lvalue, T is deduced as A& */
14675 if (TREE_CODE (*parm) == REFERENCE_TYPE
14676 && TYPE_REF_IS_RVALUE (*parm)
14677 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14678 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14679 && (arg_expr ? real_lvalue_p (arg_expr)
14680 /* try_one_overload doesn't provide an arg_expr, but
14681 functions are always lvalues. */
14682 : TREE_CODE (*arg) == FUNCTION_TYPE))
14683 *arg = build_reference_type (*arg);
14685 /* [temp.deduct.call]
14687 If P is a cv-qualified type, the top level cv-qualifiers
14688 of P's type are ignored for type deduction. If P is a
14689 reference type, the type referred to by P is used for
14691 *parm = TYPE_MAIN_VARIANT (*parm);
14692 if (TREE_CODE (*parm) == REFERENCE_TYPE)
14694 *parm = TREE_TYPE (*parm);
14695 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14698 /* DR 322. For conversion deduction, remove a reference type on parm
14699 too (which has been swapped into ARG). */
14700 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
14701 *arg = TREE_TYPE (*arg);
14706 /* Subroutine of unify_one_argument. PARM is a function parameter of a
14707 template which does contain any deducible template parameters; check if
14708 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
14709 unify_one_argument. */
14712 check_non_deducible_conversion (tree parm, tree arg, int strict,
14713 int flags, bool explain_p)
14718 type = TREE_TYPE (arg);
14722 if (same_type_p (parm, type))
14723 return unify_success (explain_p);
14725 if (strict == DEDUCE_CONV)
14727 if (can_convert_arg (type, parm, NULL_TREE, flags))
14728 return unify_success (explain_p);
14730 else if (strict != DEDUCE_EXACT)
14732 if (can_convert_arg (parm, type,
14733 TYPE_P (arg) ? NULL_TREE : arg,
14735 return unify_success (explain_p);
14738 if (strict == DEDUCE_EXACT)
14739 return unify_type_mismatch (explain_p, parm, arg);
14741 return unify_arg_conversion (explain_p, parm, type, arg);
14744 /* Subroutine of type_unification_real and unify_pack_expansion to
14745 handle unification of a single P/A pair. Parameters are as
14746 for those functions. */
14749 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
14750 int subr, unification_kind_t strict, int flags,
14753 tree arg_expr = NULL_TREE;
14756 if (arg == error_mark_node || parm == error_mark_node)
14757 return unify_invalid (explain_p);
14758 if (arg == unknown_type_node)
14759 /* We can't deduce anything from this, but we might get all the
14760 template args from other function args. */
14761 return unify_success (explain_p);
14763 /* FIXME uses_deducible_template_parms */
14764 if (TYPE_P (parm) && !uses_template_parms (parm))
14765 return check_non_deducible_conversion (parm, arg, strict, flags,
14771 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
14772 | UNIFY_ALLOW_MORE_CV_QUAL
14773 | UNIFY_ALLOW_DERIVED);
14777 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14781 arg_strict = UNIFY_ALLOW_NONE;
14785 gcc_unreachable ();
14788 /* We only do these transformations if this is the top-level
14789 parameter_type_list in a call or declaration matching; in other
14790 situations (nested function declarators, template argument lists) we
14791 won't be comparing a type to an expression, and we don't do any type
14797 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14798 if (type_unknown_p (arg))
14800 /* [temp.deduct.type] A template-argument can be
14801 deduced from a pointer to function or pointer
14802 to member function argument if the set of
14803 overloaded functions does not contain function
14804 templates and at most one of a set of
14805 overloaded functions provides a unique
14808 if (resolve_overloaded_unification
14809 (tparms, targs, parm, arg, strict,
14810 arg_strict, explain_p))
14811 return unify_success (explain_p);
14812 return unify_overload_resolution_failure (explain_p, arg);
14816 arg = unlowered_expr_type (arg);
14817 if (arg == error_mark_node)
14818 return unify_invalid (explain_p);
14822 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
14825 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
14826 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
14828 /* For deduction from an init-list we need the actual list. */
14829 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14831 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
14834 /* Most parms like fn_type_unification.
14836 If SUBR is 1, we're being called recursively (to unify the
14837 arguments of a function or method parameter of a function
14841 type_unification_real (tree tparms,
14845 unsigned int xnargs,
14847 unification_kind_t strict,
14853 int ntparms = TREE_VEC_LENGTH (tparms);
14854 int saw_undeduced = 0;
14857 unsigned int nargs;
14860 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
14861 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
14862 gcc_assert (ntparms > 0);
14864 /* Reset the number of non-defaulted template arguments contained
14866 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
14874 while (parms && parms != void_list_node
14877 parm = TREE_VALUE (parms);
14879 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
14880 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
14881 /* For a function parameter pack that occurs at the end of the
14882 parameter-declaration-list, the type A of each remaining
14883 argument of the call is compared with the type P of the
14884 declarator-id of the function parameter pack. */
14887 parms = TREE_CHAIN (parms);
14889 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
14890 /* For a function parameter pack that does not occur at the
14891 end of the parameter-declaration-list, the type of the
14892 parameter pack is a non-deduced context. */
14898 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
14904 && parms != void_list_node
14905 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
14907 /* Unify the remaining arguments with the pack expansion type. */
14909 tree parmvec = make_tree_vec (1);
14911 /* Allocate a TREE_VEC and copy in all of the arguments */
14912 argvec = make_tree_vec (nargs - ia);
14913 for (i = 0; ia < nargs; ++ia, ++i)
14914 TREE_VEC_ELT (argvec, i) = args[ia];
14916 /* Copy the parameter into parmvec. */
14917 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
14918 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
14919 /*subr=*/subr, explain_p))
14922 /* Advance to the end of the list of parameters. */
14923 parms = TREE_CHAIN (parms);
14926 /* Fail if we've reached the end of the parm list, and more args
14927 are present, and the parm list isn't variadic. */
14928 if (ia < nargs && parms == void_list_node)
14929 return unify_too_many_arguments (explain_p, nargs, ia);
14930 /* Fail if parms are left and they don't have default values. */
14931 if (parms && parms != void_list_node
14932 && TREE_PURPOSE (parms) == NULL_TREE)
14934 unsigned int count = nargs;
14936 while (p && p != void_list_node)
14939 p = TREE_CHAIN (p);
14941 return unify_too_few_arguments (explain_p, ia, count);
14946 tsubst_flags_t complain = (explain_p
14947 ? tf_warning_or_error
14950 /* Check to see if we need another pass before we start clearing
14951 ARGUMENT_PACK_INCOMPLETE_P. */
14952 for (i = 0; i < ntparms; i++)
14954 tree targ = TREE_VEC_ELT (targs, i);
14955 tree tparm = TREE_VEC_ELT (tparms, i);
14957 if (targ || tparm == error_mark_node)
14959 tparm = TREE_VALUE (tparm);
14961 /* If this is an undeduced nontype parameter that depends on
14962 a type parameter, try another pass; its type may have been
14963 deduced from a later argument than the one from which
14964 this parameter can be deduced. */
14965 if (TREE_CODE (tparm) == PARM_DECL
14966 && uses_template_parms (TREE_TYPE (tparm))
14967 && !saw_undeduced++)
14971 for (i = 0; i < ntparms; i++)
14973 tree targ = TREE_VEC_ELT (targs, i);
14974 tree tparm = TREE_VEC_ELT (tparms, i);
14976 /* Clear the "incomplete" flags on all argument packs now so that
14977 substituting them into later default arguments works. */
14978 if (targ && ARGUMENT_PACK_P (targ))
14980 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
14981 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
14984 if (targ || tparm == error_mark_node)
14986 tparm = TREE_VALUE (tparm);
14988 /* Core issue #226 (C++0x) [temp.deduct]:
14990 If a template argument has not been deduced, its
14991 default template argument, if any, is used.
14993 When we are in C++98 mode, TREE_PURPOSE will either
14994 be NULL_TREE or ERROR_MARK_NODE, so we do not need
14995 to explicitly check cxx_dialect here. */
14996 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
14998 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14999 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15000 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15001 arg = convert_template_argument (parm, arg, targs, complain,
15003 if (arg == error_mark_node)
15007 TREE_VEC_ELT (targs, i) = arg;
15008 /* The position of the first default template argument,
15009 is also the number of non-defaulted arguments in TARGS.
15011 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15012 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15017 /* If the type parameter is a parameter pack, then it will
15018 be deduced to an empty parameter pack. */
15019 if (template_parameter_pack_p (tparm))
15023 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15025 arg = make_node (NONTYPE_ARGUMENT_PACK);
15026 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15027 TREE_CONSTANT (arg) = 1;
15030 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15032 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15034 TREE_VEC_ELT (targs, i) = arg;
15038 return unify_parameter_deduction_failure (explain_p, tparm);
15041 #ifdef ENABLE_CHECKING
15042 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15043 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15046 return unify_success (explain_p);
15049 /* Subroutine of type_unification_real. Args are like the variables
15050 at the call site. ARG is an overloaded function (or template-id);
15051 we try deducing template args from each of the overloads, and if
15052 only one succeeds, we go with that. Modifies TARGS and returns
15053 true on success. */
15056 resolve_overloaded_unification (tree tparms,
15060 unification_kind_t strict,
15064 tree tempargs = copy_node (targs);
15066 tree goodfn = NULL_TREE;
15069 if (TREE_CODE (arg) == ADDR_EXPR)
15071 arg = TREE_OPERAND (arg, 0);
15077 if (TREE_CODE (arg) == COMPONENT_REF)
15078 /* Handle `&x' where `x' is some static or non-static member
15080 arg = TREE_OPERAND (arg, 1);
15082 if (TREE_CODE (arg) == OFFSET_REF)
15083 arg = TREE_OPERAND (arg, 1);
15085 /* Strip baselink information. */
15086 if (BASELINK_P (arg))
15087 arg = BASELINK_FUNCTIONS (arg);
15089 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15091 /* If we got some explicit template args, we need to plug them into
15092 the affected templates before we try to unify, in case the
15093 explicit args will completely resolve the templates in question. */
15096 tree expl_subargs = TREE_OPERAND (arg, 1);
15097 arg = TREE_OPERAND (arg, 0);
15099 for (; arg; arg = OVL_NEXT (arg))
15101 tree fn = OVL_CURRENT (arg);
15102 tree subargs, elem;
15104 if (TREE_CODE (fn) != TEMPLATE_DECL)
15107 ++processing_template_decl;
15108 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15109 expl_subargs, /*check_ret=*/false);
15110 if (subargs && !any_dependent_template_arguments_p (subargs))
15112 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15113 if (try_one_overload (tparms, targs, tempargs, parm,
15114 elem, strict, sub_strict, addr_p, explain_p)
15115 && (!goodfn || !decls_match (goodfn, elem)))
15123 --processing_template_decl;
15125 /* If no templates (or more than one) are fully resolved by the
15126 explicit arguments, this template-id is a non-deduced context; it
15127 could still be OK if we deduce all template arguments for the
15128 enclosing call through other arguments. */
15132 else if (TREE_CODE (arg) != OVERLOAD
15133 && TREE_CODE (arg) != FUNCTION_DECL)
15134 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15135 -- but the deduction does not succeed because the expression is
15136 not just the function on its own. */
15139 for (; arg; arg = OVL_NEXT (arg))
15140 if (try_one_overload (tparms, targs, tempargs, parm,
15141 TREE_TYPE (OVL_CURRENT (arg)),
15142 strict, sub_strict, addr_p, explain_p)
15143 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15145 goodfn = OVL_CURRENT (arg);
15149 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15150 to function or pointer to member function argument if the set of
15151 overloaded functions does not contain function templates and at most
15152 one of a set of overloaded functions provides a unique match.
15154 So if we found multiple possibilities, we return success but don't
15155 deduce anything. */
15159 int i = TREE_VEC_LENGTH (targs);
15161 if (TREE_VEC_ELT (tempargs, i))
15162 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15170 /* Core DR 115: In contexts where deduction is done and fails, or in
15171 contexts where deduction is not done, if a template argument list is
15172 specified and it, along with any default template arguments, identifies
15173 a single function template specialization, then the template-id is an
15174 lvalue for the function template specialization. */
15177 resolve_nondeduced_context (tree orig_expr)
15179 tree expr, offset, baselink;
15182 if (!type_unknown_p (orig_expr))
15187 offset = NULL_TREE;
15188 baselink = NULL_TREE;
15190 if (TREE_CODE (expr) == ADDR_EXPR)
15192 expr = TREE_OPERAND (expr, 0);
15195 if (TREE_CODE (expr) == OFFSET_REF)
15198 expr = TREE_OPERAND (expr, 1);
15200 if (BASELINK_P (expr))
15203 expr = BASELINK_FUNCTIONS (expr);
15206 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15209 tree goodfn = NULL_TREE;
15211 /* If we got some explicit template args, we need to plug them into
15212 the affected templates before we try to unify, in case the
15213 explicit args will completely resolve the templates in question. */
15215 tree expl_subargs = TREE_OPERAND (expr, 1);
15216 tree arg = TREE_OPERAND (expr, 0);
15217 tree badfn = NULL_TREE;
15218 tree badargs = NULL_TREE;
15220 for (; arg; arg = OVL_NEXT (arg))
15222 tree fn = OVL_CURRENT (arg);
15223 tree subargs, elem;
15225 if (TREE_CODE (fn) != TEMPLATE_DECL)
15228 ++processing_template_decl;
15229 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15230 expl_subargs, /*check_ret=*/false);
15231 if (subargs && !any_dependent_template_arguments_p (subargs))
15233 elem = instantiate_template (fn, subargs, tf_none);
15234 if (elem == error_mark_node)
15239 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15245 --processing_template_decl;
15249 mark_used (goodfn);
15252 expr = build_baselink (BASELINK_BINFO (baselink),
15253 BASELINK_ACCESS_BINFO (baselink),
15254 expr, BASELINK_OPTYPE (baselink));
15258 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15259 expr = build_offset_ref (base, expr, addr);
15262 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15265 else if (good == 0 && badargs)
15266 /* There were no good options and at least one bad one, so let the
15267 user know what the problem is. */
15268 instantiate_template (badfn, badargs, tf_warning_or_error);
15273 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15274 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15275 different overloads deduce different arguments for a given parm.
15276 ADDR_P is true if the expression for which deduction is being
15277 performed was of the form "& fn" rather than simply "fn".
15279 Returns 1 on success. */
15282 try_one_overload (tree tparms,
15287 unification_kind_t strict,
15296 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15297 to function or pointer to member function argument if the set of
15298 overloaded functions does not contain function templates and at most
15299 one of a set of overloaded functions provides a unique match.
15301 So if this is a template, just return success. */
15303 if (uses_template_parms (arg))
15306 if (TREE_CODE (arg) == METHOD_TYPE)
15307 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15309 arg = build_pointer_type (arg);
15311 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15313 /* We don't copy orig_targs for this because if we have already deduced
15314 some template args from previous args, unify would complain when we
15315 try to deduce a template parameter for the same argument, even though
15316 there isn't really a conflict. */
15317 nargs = TREE_VEC_LENGTH (targs);
15318 tempargs = make_tree_vec (nargs);
15320 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15323 /* First make sure we didn't deduce anything that conflicts with
15324 explicitly specified args. */
15325 for (i = nargs; i--; )
15327 tree elt = TREE_VEC_ELT (tempargs, i);
15328 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15332 else if (uses_template_parms (elt))
15333 /* Since we're unifying against ourselves, we will fill in
15334 template args used in the function parm list with our own
15335 template parms. Discard them. */
15336 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15337 else if (oldelt && !template_args_equal (oldelt, elt))
15341 for (i = nargs; i--; )
15343 tree elt = TREE_VEC_ELT (tempargs, i);
15346 TREE_VEC_ELT (targs, i) = elt;
15352 /* PARM is a template class (perhaps with unbound template
15353 parameters). ARG is a fully instantiated type. If ARG can be
15354 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15355 TARGS are as for unify. */
15358 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15361 tree copy_of_targs;
15363 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15364 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15365 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15368 /* We need to make a new template argument vector for the call to
15369 unify. If we used TARGS, we'd clutter it up with the result of
15370 the attempted unification, even if this class didn't work out.
15371 We also don't want to commit ourselves to all the unifications
15372 we've already done, since unification is supposed to be done on
15373 an argument-by-argument basis. In other words, consider the
15374 following pathological case:
15376 template <int I, int J, int K>
15379 template <int I, int J>
15380 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15382 template <int I, int J, int K>
15383 void f(S<I, J, K>, S<I, I, I>);
15392 Now, by the time we consider the unification involving `s2', we
15393 already know that we must have `f<0, 0, 0>'. But, even though
15394 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15395 because there are two ways to unify base classes of S<0, 1, 2>
15396 with S<I, I, I>. If we kept the already deduced knowledge, we
15397 would reject the possibility I=1. */
15398 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15400 /* If unification failed, we're done. */
15401 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15402 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15408 /* Given a template type PARM and a class type ARG, find the unique
15409 base type in ARG that is an instance of PARM. We do not examine
15410 ARG itself; only its base-classes. If there is not exactly one
15411 appropriate base class, return NULL_TREE. PARM may be the type of
15412 a partial specialization, as well as a plain template type. Used
15415 static enum template_base_result
15416 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15417 bool explain_p, tree *result)
15419 tree rval = NULL_TREE;
15422 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15424 binfo = TYPE_BINFO (complete_type (arg));
15427 /* The type could not be completed. */
15428 *result = NULL_TREE;
15429 return tbr_incomplete_type;
15432 /* Walk in inheritance graph order. The search order is not
15433 important, and this avoids multiple walks of virtual bases. */
15434 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15436 tree r = try_class_unification (tparms, targs, parm,
15437 BINFO_TYPE (binfo), explain_p);
15441 /* If there is more than one satisfactory baseclass, then:
15445 If they yield more than one possible deduced A, the type
15449 if (rval && !same_type_p (r, rval))
15451 *result = NULL_TREE;
15452 return tbr_ambiguous_baseclass;
15460 return tbr_success;
15463 /* Returns the level of DECL, which declares a template parameter. */
15466 template_decl_level (tree decl)
15468 switch (TREE_CODE (decl))
15471 case TEMPLATE_DECL:
15472 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15475 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15478 gcc_unreachable ();
15483 /* Decide whether ARG can be unified with PARM, considering only the
15484 cv-qualifiers of each type, given STRICT as documented for unify.
15485 Returns nonzero iff the unification is OK on that basis. */
15488 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15490 int arg_quals = cp_type_quals (arg);
15491 int parm_quals = cp_type_quals (parm);
15493 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15494 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15496 /* Although a CVR qualifier is ignored when being applied to a
15497 substituted template parameter ([8.3.2]/1 for example), that
15498 does not allow us to unify "const T" with "int&" because both
15499 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15500 It is ok when we're allowing additional CV qualifiers
15501 at the outer level [14.8.2.1]/3,1st bullet. */
15502 if ((TREE_CODE (arg) == REFERENCE_TYPE
15503 || TREE_CODE (arg) == FUNCTION_TYPE
15504 || TREE_CODE (arg) == METHOD_TYPE)
15505 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15508 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15509 && (parm_quals & TYPE_QUAL_RESTRICT))
15513 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15514 && (arg_quals & parm_quals) != parm_quals)
15517 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15518 && (parm_quals & arg_quals) != arg_quals)
15524 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15526 template_parm_level_and_index (tree parm, int* level, int* index)
15528 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15529 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15530 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15532 *index = TEMPLATE_TYPE_IDX (parm);
15533 *level = TEMPLATE_TYPE_LEVEL (parm);
15537 *index = TEMPLATE_PARM_IDX (parm);
15538 *level = TEMPLATE_PARM_LEVEL (parm);
15542 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15544 if (unify (TP, TA, P, A, S, EP)) \
15548 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15549 expansion at the end of PACKED_PARMS. Returns 0 if the type
15550 deduction succeeds, 1 otherwise. STRICT is the same as in
15551 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15552 call argument list. We'll need to adjust the arguments to make them
15553 types. SUBR tells us if this is from a recursive call to
15554 type_unification_real, or for comparing two template argument
15558 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15559 tree packed_args, unification_kind_t strict,
15560 bool subr, bool explain_p)
15563 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15564 tree pattern = PACK_EXPANSION_PATTERN (parm);
15565 tree pack, packs = NULL_TREE;
15566 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15567 int len = TREE_VEC_LENGTH (packed_args);
15569 /* Determine the parameter packs we will be deducing from the
15570 pattern, and record their current deductions. */
15571 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15572 pack; pack = TREE_CHAIN (pack))
15574 tree parm_pack = TREE_VALUE (pack);
15577 /* Determine the index and level of this parameter pack. */
15578 template_parm_level_and_index (parm_pack, &level, &idx);
15580 /* Keep track of the parameter packs and their corresponding
15582 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15583 TREE_TYPE (packs) = make_tree_vec (len - start);
15586 /* Loop through all of the arguments that have not yet been
15587 unified and unify each with the pattern. */
15588 for (i = start; i < len; i++)
15591 bool any_explicit = false;
15592 tree arg = TREE_VEC_ELT (packed_args, i);
15594 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
15595 or the element of its argument pack at the current index if
15596 this argument was explicitly specified. */
15597 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15601 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15604 if (TREE_VALUE (pack)
15605 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
15606 && (i < TREE_VEC_LENGTH (pargs)))
15608 any_explicit = true;
15609 arg = TREE_VEC_ELT (pargs, i);
15611 TMPL_ARG (targs, level, idx) = arg;
15614 /* If we had explicit template arguments, substitute them into the
15615 pattern before deduction. */
15618 /* Some arguments might still be unspecified or dependent. */
15620 ++processing_template_decl;
15621 dependent = any_dependent_template_arguments_p (targs);
15623 --processing_template_decl;
15624 parm = tsubst (pattern, targs,
15625 explain_p ? tf_warning_or_error : tf_none,
15628 --processing_template_decl;
15629 if (parm == error_mark_node)
15635 /* Unify the pattern with the current argument. */
15636 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15637 LOOKUP_IMPLICIT, explain_p))
15640 /* For each parameter pack, collect the deduced value. */
15641 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15644 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15646 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
15647 TMPL_ARG (targs, level, idx);
15651 /* Verify that the results of unification with the parameter packs
15652 produce results consistent with what we've seen before, and make
15653 the deduced argument packs available. */
15654 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15656 tree old_pack = TREE_VALUE (pack);
15657 tree new_args = TREE_TYPE (pack);
15658 int i, len = TREE_VEC_LENGTH (new_args);
15660 bool nondeduced_p = false;
15662 /* By default keep the original deduced argument pack.
15663 If necessary, more specific code is going to update the
15664 resulting deduced argument later down in this function. */
15665 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15666 TMPL_ARG (targs, level, idx) = old_pack;
15668 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
15669 actually deduce anything. */
15670 for (i = 0; i < len && !nondeduced_p; ++i)
15671 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
15672 nondeduced_p = true;
15676 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
15678 /* If we had fewer function args than explicit template args,
15679 just use the explicits. */
15680 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15681 int explicit_len = TREE_VEC_LENGTH (explicit_args);
15682 if (len < explicit_len)
15683 new_args = explicit_args;
15689 /* Build the deduced *_ARGUMENT_PACK. */
15690 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
15692 result = make_node (NONTYPE_ARGUMENT_PACK);
15693 TREE_TYPE (result) =
15694 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
15695 TREE_CONSTANT (result) = 1;
15698 result = cxx_make_type (TYPE_ARGUMENT_PACK);
15700 SET_ARGUMENT_PACK_ARGS (result, new_args);
15702 /* Note the deduced argument packs for this parameter
15704 TMPL_ARG (targs, level, idx) = result;
15706 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
15707 && (ARGUMENT_PACK_ARGS (old_pack)
15708 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
15710 /* We only had the explicitly-provided arguments before, but
15711 now we have a complete set of arguments. */
15712 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
15714 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
15715 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
15716 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
15720 tree bad_old_arg, bad_new_arg;
15721 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
15723 if (!comp_template_args_with_info (old_args, new_args,
15724 &bad_old_arg, &bad_new_arg))
15725 /* Inconsistent unification of this parameter pack. */
15726 return unify_parameter_pack_inconsistent (explain_p,
15732 return unify_success (explain_p);
15735 /* Deduce the value of template parameters. TPARMS is the (innermost)
15736 set of template parameters to a template. TARGS is the bindings
15737 for those template parameters, as determined thus far; TARGS may
15738 include template arguments for outer levels of template parameters
15739 as well. PARM is a parameter to a template function, or a
15740 subcomponent of that parameter; ARG is the corresponding argument.
15741 This function attempts to match PARM with ARG in a manner
15742 consistent with the existing assignments in TARGS. If more values
15743 are deduced, then TARGS is updated.
15745 Returns 0 if the type deduction succeeds, 1 otherwise. The
15746 parameter STRICT is a bitwise or of the following flags:
15749 Require an exact match between PARM and ARG.
15750 UNIFY_ALLOW_MORE_CV_QUAL:
15751 Allow the deduced ARG to be more cv-qualified (by qualification
15752 conversion) than ARG.
15753 UNIFY_ALLOW_LESS_CV_QUAL:
15754 Allow the deduced ARG to be less cv-qualified than ARG.
15755 UNIFY_ALLOW_DERIVED:
15756 Allow the deduced ARG to be a template base class of ARG,
15757 or a pointer to a template base class of the type pointed to by
15759 UNIFY_ALLOW_INTEGER:
15760 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
15761 case for more information.
15762 UNIFY_ALLOW_OUTER_LEVEL:
15763 This is the outermost level of a deduction. Used to determine validity
15764 of qualification conversions. A valid qualification conversion must
15765 have const qualified pointers leading up to the inner type which
15766 requires additional CV quals, except at the outer level, where const
15767 is not required [conv.qual]. It would be normal to set this flag in
15768 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
15769 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
15770 This is the outermost level of a deduction, and PARM can be more CV
15771 qualified at this point.
15772 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
15773 This is the outermost level of a deduction, and PARM can be less CV
15774 qualified at this point. */
15777 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
15783 int strict_in = strict;
15785 /* I don't think this will do the right thing with respect to types.
15786 But the only case I've seen it in so far has been array bounds, where
15787 signedness is the only information lost, and I think that will be
15789 while (TREE_CODE (parm) == NOP_EXPR)
15790 parm = TREE_OPERAND (parm, 0);
15792 if (arg == error_mark_node)
15793 return unify_invalid (explain_p);
15794 if (arg == unknown_type_node
15795 || arg == init_list_type_node)
15796 /* We can't deduce anything from this, but we might get all the
15797 template args from other function args. */
15798 return unify_success (explain_p);
15800 /* If PARM uses template parameters, then we can't bail out here,
15801 even if ARG == PARM, since we won't record unifications for the
15802 template parameters. We might need them if we're trying to
15803 figure out which of two things is more specialized. */
15804 if (arg == parm && !uses_template_parms (parm))
15805 return unify_success (explain_p);
15807 /* Handle init lists early, so the rest of the function can assume
15808 we're dealing with a type. */
15809 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
15813 tree orig_parm = parm;
15815 /* Replace T with std::initializer_list<T> for deduction. */
15816 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15817 && flag_deduce_init_list)
15818 parm = listify (parm);
15820 if (!is_std_init_list (parm))
15821 /* We can only deduce from an initializer list argument if the
15822 parameter is std::initializer_list; otherwise this is a
15823 non-deduced context. */
15824 return unify_success (explain_p);
15826 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
15828 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
15830 int elt_strict = strict;
15832 if (elt == error_mark_node)
15833 return unify_invalid (explain_p);
15835 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
15837 tree type = TREE_TYPE (elt);
15838 /* It should only be possible to get here for a call. */
15839 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
15840 elt_strict |= maybe_adjust_types_for_deduction
15841 (DEDUCE_CALL, &elttype, &type, elt);
15845 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
15849 /* If the std::initializer_list<T> deduction worked, replace the
15850 deduced A with std::initializer_list<A>. */
15851 if (orig_parm != parm)
15853 idx = TEMPLATE_TYPE_IDX (orig_parm);
15854 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15855 targ = listify (targ);
15856 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
15858 return unify_success (explain_p);
15861 /* Immediately reject some pairs that won't unify because of
15862 cv-qualification mismatches. */
15863 if (TREE_CODE (arg) == TREE_CODE (parm)
15865 /* It is the elements of the array which hold the cv quals of an array
15866 type, and the elements might be template type parms. We'll check
15867 when we recurse. */
15868 && TREE_CODE (arg) != ARRAY_TYPE
15869 /* We check the cv-qualifiers when unifying with template type
15870 parameters below. We want to allow ARG `const T' to unify with
15871 PARM `T' for example, when computing which of two templates
15872 is more specialized, for example. */
15873 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
15874 && !check_cv_quals_for_unify (strict_in, arg, parm))
15875 return unify_cv_qual_mismatch (explain_p, parm, arg);
15877 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
15878 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
15879 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
15880 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
15881 strict &= ~UNIFY_ALLOW_DERIVED;
15882 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15883 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
15885 switch (TREE_CODE (parm))
15887 case TYPENAME_TYPE:
15889 case UNBOUND_CLASS_TEMPLATE:
15890 /* In a type which contains a nested-name-specifier, template
15891 argument values cannot be deduced for template parameters used
15892 within the nested-name-specifier. */
15893 return unify_success (explain_p);
15895 case TEMPLATE_TYPE_PARM:
15896 case TEMPLATE_TEMPLATE_PARM:
15897 case BOUND_TEMPLATE_TEMPLATE_PARM:
15898 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
15899 if (tparm == error_mark_node)
15900 return unify_invalid (explain_p);
15902 if (TEMPLATE_TYPE_LEVEL (parm)
15903 != template_decl_level (tparm))
15904 /* The PARM is not one we're trying to unify. Just check
15905 to see if it matches ARG. */
15907 if (TREE_CODE (arg) == TREE_CODE (parm)
15908 && same_type_p (parm, arg))
15909 return unify_success (explain_p);
15911 return unify_type_mismatch (explain_p, parm, arg);
15913 idx = TEMPLATE_TYPE_IDX (parm);
15914 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
15915 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
15917 /* Check for mixed types and values. */
15918 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15919 && TREE_CODE (tparm) != TYPE_DECL)
15920 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15921 && TREE_CODE (tparm) != TEMPLATE_DECL))
15922 gcc_unreachable ();
15924 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15926 /* ARG must be constructed from a template class or a template
15927 template parameter. */
15928 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
15929 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
15930 return unify_template_deduction_failure (explain_p, parm, arg);
15933 tree parmvec = TYPE_TI_ARGS (parm);
15934 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
15935 tree full_argvec = add_to_template_args (targs, argvec);
15937 = DECL_INNERMOST_TEMPLATE_PARMS
15938 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
15940 int parm_variadic_p = 0;
15942 /* The resolution to DR150 makes clear that default
15943 arguments for an N-argument may not be used to bind T
15944 to a template template parameter with fewer than N
15945 parameters. It is not safe to permit the binding of
15946 default arguments as an extension, as that may change
15947 the meaning of a conforming program. Consider:
15949 struct Dense { static const unsigned int dim = 1; };
15951 template <template <typename> class View,
15953 void operator+(float, View<Block> const&);
15955 template <typename Block,
15956 unsigned int Dim = Block::dim>
15957 struct Lvalue_proxy { operator float() const; };
15961 Lvalue_proxy<Dense> p;
15966 Here, if Lvalue_proxy is permitted to bind to View, then
15967 the global operator+ will be used; if they are not, the
15968 Lvalue_proxy will be converted to float. */
15969 if (coerce_template_parms (parm_parms,
15971 TYPE_TI_TEMPLATE (parm),
15973 ? tf_warning_or_error
15975 /*require_all_args=*/true,
15976 /*use_default_args=*/false)
15977 == error_mark_node)
15980 /* Deduce arguments T, i from TT<T> or TT<i>.
15981 We check each element of PARMVEC and ARGVEC individually
15982 rather than the whole TREE_VEC since they can have
15983 different number of elements. */
15985 parmvec = expand_template_argument_pack (parmvec);
15986 argvec = expand_template_argument_pack (argvec);
15988 len = TREE_VEC_LENGTH (parmvec);
15990 /* Check if the parameters end in a pack, making them
15993 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
15994 parm_variadic_p = 1;
15996 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
15997 return unify_too_few_arguments (explain_p,
15998 TREE_VEC_LENGTH (argvec), len);
16000 for (i = 0; i < len - parm_variadic_p; ++i)
16002 RECUR_AND_CHECK_FAILURE (tparms, targs,
16003 TREE_VEC_ELT (parmvec, i),
16004 TREE_VEC_ELT (argvec, i),
16005 UNIFY_ALLOW_NONE, explain_p);
16008 if (parm_variadic_p
16009 && unify_pack_expansion (tparms, targs,
16012 /*subr=*/true, explain_p))
16015 arg = TYPE_TI_TEMPLATE (arg);
16017 /* Fall through to deduce template name. */
16020 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16021 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16023 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16025 /* Simple cases: Value already set, does match or doesn't. */
16026 if (targ != NULL_TREE && template_args_equal (targ, arg))
16027 return unify_success (explain_p);
16029 return unify_inconsistency (explain_p, parm, targ, arg);
16033 /* If PARM is `const T' and ARG is only `int', we don't have
16034 a match unless we are allowing additional qualification.
16035 If ARG is `const int' and PARM is just `T' that's OK;
16036 that binds `const int' to `T'. */
16037 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16039 return unify_cv_qual_mismatch (explain_p, parm, arg);
16041 /* Consider the case where ARG is `const volatile int' and
16042 PARM is `const T'. Then, T should be `volatile int'. */
16043 arg = cp_build_qualified_type_real
16044 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16045 if (arg == error_mark_node)
16046 return unify_invalid (explain_p);
16048 /* Simple cases: Value already set, does match or doesn't. */
16049 if (targ != NULL_TREE && same_type_p (targ, arg))
16050 return unify_success (explain_p);
16052 return unify_inconsistency (explain_p, parm, targ, arg);
16054 /* Make sure that ARG is not a variable-sized array. (Note
16055 that were talking about variable-sized arrays (like
16056 `int[n]'), rather than arrays of unknown size (like
16057 `int[]').) We'll get very confused by such a type since
16058 the bound of the array is not constant, and therefore
16059 not mangleable. Besides, such types are not allowed in
16060 ISO C++, so we can do as we please here. We do allow
16061 them for 'auto' deduction, since that isn't ABI-exposed. */
16062 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16063 return unify_vla_arg (explain_p, arg);
16065 /* Strip typedefs as in convert_template_argument. */
16066 arg = canonicalize_type_argument (arg, tf_none);
16069 /* If ARG is a parameter pack or an expansion, we cannot unify
16070 against it unless PARM is also a parameter pack. */
16071 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16072 && !template_parameter_pack_p (parm))
16073 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16075 /* If the argument deduction results is a METHOD_TYPE,
16076 then there is a problem.
16077 METHOD_TYPE doesn't map to any real C++ type the result of
16078 the deduction can not be of that type. */
16079 if (TREE_CODE (arg) == METHOD_TYPE)
16080 return unify_method_type_error (explain_p, arg);
16082 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16083 return unify_success (explain_p);
16085 case TEMPLATE_PARM_INDEX:
16086 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16087 if (tparm == error_mark_node)
16088 return unify_invalid (explain_p);
16090 if (TEMPLATE_PARM_LEVEL (parm)
16091 != template_decl_level (tparm))
16093 /* The PARM is not one we're trying to unify. Just check
16094 to see if it matches ARG. */
16095 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16096 && cp_tree_equal (parm, arg));
16098 unify_expression_unequal (explain_p, parm, arg);
16102 idx = TEMPLATE_PARM_IDX (parm);
16103 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16107 int x = !cp_tree_equal (targ, arg);
16109 unify_inconsistency (explain_p, parm, targ, arg);
16113 /* [temp.deduct.type] If, in the declaration of a function template
16114 with a non-type template-parameter, the non-type
16115 template-parameter is used in an expression in the function
16116 parameter-list and, if the corresponding template-argument is
16117 deduced, the template-argument type shall match the type of the
16118 template-parameter exactly, except that a template-argument
16119 deduced from an array bound may be of any integral type.
16120 The non-type parameter might use already deduced type parameters. */
16121 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16122 if (!TREE_TYPE (arg))
16123 /* Template-parameter dependent expression. Just accept it for now.
16124 It will later be processed in convert_template_argument. */
16126 else if (same_type_p (TREE_TYPE (arg), tparm))
16128 else if ((strict & UNIFY_ALLOW_INTEGER)
16129 && (TREE_CODE (tparm) == INTEGER_TYPE
16130 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16131 /* Convert the ARG to the type of PARM; the deduced non-type
16132 template argument must exactly match the types of the
16133 corresponding parameter. */
16134 arg = fold (build_nop (tparm, arg));
16135 else if (uses_template_parms (tparm))
16136 /* We haven't deduced the type of this parameter yet. Try again
16138 return unify_success (explain_p);
16140 return unify_type_mismatch (explain_p, tparm, arg);
16142 /* If ARG is a parameter pack or an expansion, we cannot unify
16143 against it unless PARM is also a parameter pack. */
16144 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16145 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16146 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16148 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16149 return unify_success (explain_p);
16153 /* A pointer-to-member constant can be unified only with
16154 another constant. */
16155 if (TREE_CODE (arg) != PTRMEM_CST)
16156 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16158 /* Just unify the class member. It would be useless (and possibly
16159 wrong, depending on the strict flags) to unify also
16160 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16161 arg refer to the same variable, even if through different
16162 classes. For instance:
16164 struct A { int x; };
16167 Unification of &A::x and &B::x must succeed. */
16168 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16169 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16174 if (TREE_CODE (arg) != POINTER_TYPE)
16175 return unify_type_mismatch (explain_p, parm, arg);
16177 /* [temp.deduct.call]
16179 A can be another pointer or pointer to member type that can
16180 be converted to the deduced A via a qualification
16181 conversion (_conv.qual_).
16183 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16184 This will allow for additional cv-qualification of the
16185 pointed-to types if appropriate. */
16187 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16188 /* The derived-to-base conversion only persists through one
16189 level of pointers. */
16190 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16192 return unify (tparms, targs, TREE_TYPE (parm),
16193 TREE_TYPE (arg), strict, explain_p);
16196 case REFERENCE_TYPE:
16197 if (TREE_CODE (arg) != REFERENCE_TYPE)
16198 return unify_type_mismatch (explain_p, parm, arg);
16199 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16200 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16203 if (TREE_CODE (arg) != ARRAY_TYPE)
16204 return unify_type_mismatch (explain_p, parm, arg);
16205 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16206 != (TYPE_DOMAIN (arg) == NULL_TREE))
16207 return unify_type_mismatch (explain_p, parm, arg);
16208 if (TYPE_DOMAIN (parm) != NULL_TREE)
16215 /* Our representation of array types uses "N - 1" as the
16216 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16217 not an integer constant. We cannot unify arbitrarily
16218 complex expressions, so we eliminate the MINUS_EXPRs
16220 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16221 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16224 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16225 parm_max = TREE_OPERAND (parm_max, 0);
16227 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16228 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16231 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16232 trying to unify the type of a variable with the type
16233 of a template parameter. For example:
16235 template <unsigned int N>
16236 void f (char (&) [N]);
16243 Here, the type of the ARG will be "int [g(i)]", and
16244 may be a SAVE_EXPR, etc. */
16245 if (TREE_CODE (arg_max) != MINUS_EXPR)
16246 return unify_vla_arg (explain_p, arg);
16247 arg_max = TREE_OPERAND (arg_max, 0);
16250 /* If only one of the bounds used a MINUS_EXPR, compensate
16251 by adding one to the other bound. */
16252 if (parm_cst && !arg_cst)
16253 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16257 else if (arg_cst && !parm_cst)
16258 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16263 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16264 UNIFY_ALLOW_INTEGER, explain_p);
16266 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16267 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16274 case ENUMERAL_TYPE:
16276 if (TREE_CODE (arg) != TREE_CODE (parm))
16277 return unify_type_mismatch (explain_p, parm, arg);
16279 /* We have already checked cv-qualification at the top of the
16281 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16282 return unify_type_mismatch (explain_p, parm, arg);
16284 /* As far as unification is concerned, this wins. Later checks
16285 will invalidate it if necessary. */
16286 return unify_success (explain_p);
16288 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16289 /* Type INTEGER_CST can come from ordinary constant template args. */
16291 while (TREE_CODE (arg) == NOP_EXPR)
16292 arg = TREE_OPERAND (arg, 0);
16294 if (TREE_CODE (arg) != INTEGER_CST)
16295 return unify_template_argument_mismatch (explain_p, parm, arg);
16296 return (tree_int_cst_equal (parm, arg)
16297 ? unify_success (explain_p)
16298 : unify_template_argument_mismatch (explain_p, parm, arg));
16302 int i, len, argslen;
16303 int parm_variadic_p = 0;
16305 if (TREE_CODE (arg) != TREE_VEC)
16306 return unify_template_argument_mismatch (explain_p, parm, arg);
16308 len = TREE_VEC_LENGTH (parm);
16309 argslen = TREE_VEC_LENGTH (arg);
16311 /* Check for pack expansions in the parameters. */
16312 for (i = 0; i < len; ++i)
16314 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16317 /* We can unify against something with a trailing
16319 parm_variadic_p = 1;
16321 /* [temp.deduct.type]/9: If the template argument list of
16322 P contains a pack expansion that is not the last
16323 template argument, the entire template argument list
16324 is a non-deduced context. */
16325 return unify_success (explain_p);
16329 /* If we don't have enough arguments to satisfy the parameters
16330 (not counting the pack expression at the end), or we have
16331 too many arguments for a parameter list that doesn't end in
16332 a pack expression, we can't unify. */
16333 if (parm_variadic_p
16334 ? argslen < len - parm_variadic_p
16336 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16338 /* Unify all of the parameters that precede the (optional)
16339 pack expression. */
16340 for (i = 0; i < len - parm_variadic_p; ++i)
16342 RECUR_AND_CHECK_FAILURE (tparms, targs,
16343 TREE_VEC_ELT (parm, i),
16344 TREE_VEC_ELT (arg, i),
16345 UNIFY_ALLOW_NONE, explain_p);
16347 if (parm_variadic_p)
16348 return unify_pack_expansion (tparms, targs, parm, arg,
16350 /*subr=*/true, explain_p);
16351 return unify_success (explain_p);
16356 if (TREE_CODE (arg) != TREE_CODE (parm))
16357 return unify_type_mismatch (explain_p, parm, arg);
16359 if (TYPE_PTRMEMFUNC_P (parm))
16361 if (!TYPE_PTRMEMFUNC_P (arg))
16362 return unify_type_mismatch (explain_p, parm, arg);
16364 return unify (tparms, targs,
16365 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16366 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16367 strict, explain_p);
16370 if (CLASSTYPE_TEMPLATE_INFO (parm))
16372 tree t = NULL_TREE;
16374 if (strict_in & UNIFY_ALLOW_DERIVED)
16376 /* First, we try to unify the PARM and ARG directly. */
16377 t = try_class_unification (tparms, targs,
16378 parm, arg, explain_p);
16382 /* Fallback to the special case allowed in
16383 [temp.deduct.call]:
16385 If P is a class, and P has the form
16386 template-id, then A can be a derived class of
16387 the deduced A. Likewise, if P is a pointer to
16388 a class of the form template-id, A can be a
16389 pointer to a derived class pointed to by the
16391 enum template_base_result r;
16392 r = get_template_base (tparms, targs, parm, arg,
16396 return unify_no_common_base (explain_p, r, parm, arg);
16399 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16400 && (CLASSTYPE_TI_TEMPLATE (parm)
16401 == CLASSTYPE_TI_TEMPLATE (arg)))
16402 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16403 Then, we should unify `int' and `U'. */
16406 /* There's no chance of unification succeeding. */
16407 return unify_type_mismatch (explain_p, parm, arg);
16409 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16410 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16412 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16413 return unify_type_mismatch (explain_p, parm, arg);
16414 return unify_success (explain_p);
16417 case FUNCTION_TYPE:
16419 unsigned int nargs;
16424 if (TREE_CODE (arg) != TREE_CODE (parm))
16425 return unify_type_mismatch (explain_p, parm, arg);
16427 /* CV qualifications for methods can never be deduced, they must
16428 match exactly. We need to check them explicitly here,
16429 because type_unification_real treats them as any other
16430 cv-qualified parameter. */
16431 if (TREE_CODE (parm) == METHOD_TYPE
16432 && (!check_cv_quals_for_unify
16434 class_of_this_parm (arg),
16435 class_of_this_parm (parm))))
16436 return unify_cv_qual_mismatch (explain_p, parm, arg);
16438 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16439 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16441 nargs = list_length (TYPE_ARG_TYPES (arg));
16442 args = XALLOCAVEC (tree, nargs);
16443 for (a = TYPE_ARG_TYPES (arg), i = 0;
16444 a != NULL_TREE && a != void_list_node;
16445 a = TREE_CHAIN (a), ++i)
16446 args[i] = TREE_VALUE (a);
16449 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16450 args, nargs, 1, DEDUCE_EXACT,
16451 LOOKUP_NORMAL, explain_p);
16455 /* Unify a pointer to member with a pointer to member function, which
16456 deduces the type of the member as a function type. */
16457 if (TYPE_PTRMEMFUNC_P (arg))
16462 /* Check top-level cv qualifiers */
16463 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16464 return unify_cv_qual_mismatch (explain_p, parm, arg);
16466 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16467 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16468 UNIFY_ALLOW_NONE, explain_p);
16470 /* Determine the type of the function we are unifying against. */
16471 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16473 build_function_type (TREE_TYPE (method_type),
16474 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16476 /* Extract the cv-qualifiers of the member function from the
16477 implicit object parameter and place them on the function
16478 type to be restored later. */
16479 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16480 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16483 if (TREE_CODE (arg) != OFFSET_TYPE)
16484 return unify_type_mismatch (explain_p, parm, arg);
16485 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16486 TYPE_OFFSET_BASETYPE (arg),
16487 UNIFY_ALLOW_NONE, explain_p);
16488 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16489 strict, explain_p);
16492 if (DECL_TEMPLATE_PARM_P (parm))
16493 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16494 if (arg != integral_constant_value (parm))
16495 return unify_template_argument_mismatch (explain_p, parm, arg);
16496 return unify_success (explain_p);
16499 case TEMPLATE_DECL:
16500 /* Matched cases are handled by the ARG == PARM test above. */
16501 return unify_template_argument_mismatch (explain_p, parm, arg);
16504 /* A non-type template parameter that is a variable should be a
16505 an integral constant, in which case, it whould have been
16506 folded into its (constant) value. So we should not be getting
16507 a variable here. */
16508 gcc_unreachable ();
16510 case TYPE_ARGUMENT_PACK:
16511 case NONTYPE_ARGUMENT_PACK:
16512 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16513 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16516 case DECLTYPE_TYPE:
16517 case UNDERLYING_TYPE:
16518 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16519 or UNDERLYING_TYPE nodes. */
16520 return unify_success (explain_p);
16523 /* Unification fails if we hit an error node. */
16524 return unify_invalid (explain_p);
16527 /* An unresolved overload is a nondeduced context. */
16528 if (type_unknown_p (parm))
16529 return unify_success (explain_p);
16530 gcc_assert (EXPR_P (parm));
16532 /* We must be looking at an expression. This can happen with
16536 void foo(S<I>, S<I + 2>);
16538 This is a "nondeduced context":
16542 The nondeduced contexts are:
16544 --A type that is a template-id in which one or more of
16545 the template-arguments is an expression that references
16546 a template-parameter.
16548 In these cases, we assume deduction succeeded, but don't
16549 actually infer any unifications. */
16551 if (!uses_template_parms (parm)
16552 && !template_args_equal (parm, arg))
16553 return unify_expression_unequal (explain_p, parm, arg);
16555 return unify_success (explain_p);
16558 #undef RECUR_AND_CHECK_FAILURE
16560 /* Note that DECL can be defined in this translation unit, if
16564 mark_definable (tree decl)
16567 DECL_NOT_REALLY_EXTERN (decl) = 1;
16568 FOR_EACH_CLONE (clone, decl)
16569 DECL_NOT_REALLY_EXTERN (clone) = 1;
16572 /* Called if RESULT is explicitly instantiated, or is a member of an
16573 explicitly instantiated class. */
16576 mark_decl_instantiated (tree result, int extern_p)
16578 SET_DECL_EXPLICIT_INSTANTIATION (result);
16580 /* If this entity has already been written out, it's too late to
16581 make any modifications. */
16582 if (TREE_ASM_WRITTEN (result))
16585 if (TREE_CODE (result) != FUNCTION_DECL)
16586 /* The TREE_PUBLIC flag for function declarations will have been
16587 set correctly by tsubst. */
16588 TREE_PUBLIC (result) = 1;
16590 /* This might have been set by an earlier implicit instantiation. */
16591 DECL_COMDAT (result) = 0;
16594 DECL_NOT_REALLY_EXTERN (result) = 0;
16597 mark_definable (result);
16598 /* Always make artificials weak. */
16599 if (DECL_ARTIFICIAL (result) && flag_weak)
16600 comdat_linkage (result);
16601 /* For WIN32 we also want to put explicit instantiations in
16602 linkonce sections. */
16603 else if (TREE_PUBLIC (result))
16604 maybe_make_one_only (result);
16607 /* If EXTERN_P, then this function will not be emitted -- unless
16608 followed by an explicit instantiation, at which point its linkage
16609 will be adjusted. If !EXTERN_P, then this function will be
16610 emitted here. In neither circumstance do we want
16611 import_export_decl to adjust the linkage. */
16612 DECL_INTERFACE_KNOWN (result) = 1;
16615 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16616 important template arguments. If any are missing, we check whether
16617 they're important by using error_mark_node for substituting into any
16618 args that were used for partial ordering (the ones between ARGS and END)
16619 and seeing if it bubbles up. */
16622 check_undeduced_parms (tree targs, tree args, tree end)
16624 bool found = false;
16626 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16627 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16630 TREE_VEC_ELT (targs, i) = error_mark_node;
16634 for (; args != end; args = TREE_CHAIN (args))
16636 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
16637 if (substed == error_mark_node)
16644 /* Given two function templates PAT1 and PAT2, return:
16646 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
16647 -1 if PAT2 is more specialized than PAT1.
16648 0 if neither is more specialized.
16650 LEN indicates the number of parameters we should consider
16651 (defaulted parameters should not be considered).
16653 The 1998 std underspecified function template partial ordering, and
16654 DR214 addresses the issue. We take pairs of arguments, one from
16655 each of the templates, and deduce them against each other. One of
16656 the templates will be more specialized if all the *other*
16657 template's arguments deduce against its arguments and at least one
16658 of its arguments *does* *not* deduce against the other template's
16659 corresponding argument. Deduction is done as for class templates.
16660 The arguments used in deduction have reference and top level cv
16661 qualifiers removed. Iff both arguments were originally reference
16662 types *and* deduction succeeds in both directions, the template
16663 with the more cv-qualified argument wins for that pairing (if
16664 neither is more cv-qualified, they both are equal). Unlike regular
16665 deduction, after all the arguments have been deduced in this way,
16666 we do *not* verify the deduced template argument values can be
16667 substituted into non-deduced contexts.
16669 The logic can be a bit confusing here, because we look at deduce1 and
16670 targs1 to see if pat2 is at least as specialized, and vice versa; if we
16671 can find template arguments for pat1 to make arg1 look like arg2, that
16672 means that arg2 is at least as specialized as arg1. */
16675 more_specialized_fn (tree pat1, tree pat2, int len)
16677 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
16678 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
16679 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
16680 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
16681 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
16682 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
16683 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
16684 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
16685 tree origs1, origs2;
16686 bool lose1 = false;
16687 bool lose2 = false;
16689 /* Remove the this parameter from non-static member functions. If
16690 one is a non-static member function and the other is not a static
16691 member function, remove the first parameter from that function
16692 also. This situation occurs for operator functions where we
16693 locate both a member function (with this pointer) and non-member
16694 operator (with explicit first operand). */
16695 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
16697 len--; /* LEN is the number of significant arguments for DECL1 */
16698 args1 = TREE_CHAIN (args1);
16699 if (!DECL_STATIC_FUNCTION_P (decl2))
16700 args2 = TREE_CHAIN (args2);
16702 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
16704 args2 = TREE_CHAIN (args2);
16705 if (!DECL_STATIC_FUNCTION_P (decl1))
16708 args1 = TREE_CHAIN (args1);
16712 /* If only one is a conversion operator, they are unordered. */
16713 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
16716 /* Consider the return type for a conversion function */
16717 if (DECL_CONV_FN_P (decl1))
16719 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
16720 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
16724 processing_template_decl++;
16730 /* Stop when an ellipsis is seen. */
16731 && args1 != NULL_TREE && args2 != NULL_TREE)
16733 tree arg1 = TREE_VALUE (args1);
16734 tree arg2 = TREE_VALUE (args2);
16735 int deduce1, deduce2;
16739 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16740 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16742 /* When both arguments are pack expansions, we need only
16743 unify the patterns themselves. */
16744 arg1 = PACK_EXPANSION_PATTERN (arg1);
16745 arg2 = PACK_EXPANSION_PATTERN (arg2);
16747 /* This is the last comparison we need to do. */
16751 if (TREE_CODE (arg1) == REFERENCE_TYPE)
16753 arg1 = TREE_TYPE (arg1);
16754 quals1 = cp_type_quals (arg1);
16757 if (TREE_CODE (arg2) == REFERENCE_TYPE)
16759 arg2 = TREE_TYPE (arg2);
16760 quals2 = cp_type_quals (arg2);
16763 if ((quals1 < 0) != (quals2 < 0))
16765 /* Only of the args is a reference, see if we should apply
16766 array/function pointer decay to it. This is not part of
16767 DR214, but is, IMHO, consistent with the deduction rules
16768 for the function call itself, and with our earlier
16769 implementation of the underspecified partial ordering
16770 rules. (nathan). */
16773 switch (TREE_CODE (arg1))
16776 arg1 = TREE_TYPE (arg1);
16778 case FUNCTION_TYPE:
16779 arg1 = build_pointer_type (arg1);
16788 switch (TREE_CODE (arg2))
16791 arg2 = TREE_TYPE (arg2);
16793 case FUNCTION_TYPE:
16794 arg2 = build_pointer_type (arg2);
16803 arg1 = TYPE_MAIN_VARIANT (arg1);
16804 arg2 = TYPE_MAIN_VARIANT (arg2);
16806 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
16808 int i, len2 = list_length (args2);
16809 tree parmvec = make_tree_vec (1);
16810 tree argvec = make_tree_vec (len2);
16813 /* Setup the parameter vector, which contains only ARG1. */
16814 TREE_VEC_ELT (parmvec, 0) = arg1;
16816 /* Setup the argument vector, which contains the remaining
16818 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
16819 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16821 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
16822 argvec, DEDUCE_EXACT,
16823 /*subr=*/true, /*explain_p=*/false)
16826 /* We cannot deduce in the other direction, because ARG1 is
16827 a pack expansion but ARG2 is not. */
16830 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16832 int i, len1 = list_length (args1);
16833 tree parmvec = make_tree_vec (1);
16834 tree argvec = make_tree_vec (len1);
16837 /* Setup the parameter vector, which contains only ARG1. */
16838 TREE_VEC_ELT (parmvec, 0) = arg2;
16840 /* Setup the argument vector, which contains the remaining
16842 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
16843 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
16845 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
16846 argvec, DEDUCE_EXACT,
16847 /*subr=*/true, /*explain_p=*/false)
16850 /* We cannot deduce in the other direction, because ARG2 is
16851 a pack expansion but ARG1 is not.*/
16857 /* The normal case, where neither argument is a pack
16859 deduce1 = (unify (tparms1, targs1, arg1, arg2,
16860 UNIFY_ALLOW_NONE, /*explain_p=*/false)
16862 deduce2 = (unify (tparms2, targs2, arg2, arg1,
16863 UNIFY_ALLOW_NONE, /*explain_p=*/false)
16867 /* If we couldn't deduce arguments for tparms1 to make arg1 match
16868 arg2, then arg2 is not as specialized as arg1. */
16874 /* "If, for a given type, deduction succeeds in both directions
16875 (i.e., the types are identical after the transformations above)
16876 and if the type from the argument template is more cv-qualified
16877 than the type from the parameter template (as described above)
16878 that type is considered to be more specialized than the other. If
16879 neither type is more cv-qualified than the other then neither type
16880 is more specialized than the other." */
16882 if (deduce1 && deduce2
16883 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
16885 if ((quals1 & quals2) == quals2)
16887 if ((quals1 & quals2) == quals1)
16891 if (lose1 && lose2)
16892 /* We've failed to deduce something in either direction.
16893 These must be unordered. */
16896 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
16897 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
16898 /* We have already processed all of the arguments in our
16899 handing of the pack expansion type. */
16902 args1 = TREE_CHAIN (args1);
16903 args2 = TREE_CHAIN (args2);
16906 /* "In most cases, all template parameters must have values in order for
16907 deduction to succeed, but for partial ordering purposes a template
16908 parameter may remain without a value provided it is not used in the
16909 types being used for partial ordering."
16911 Thus, if we are missing any of the targs1 we need to substitute into
16912 origs1, then pat2 is not as specialized as pat1. This can happen when
16913 there is a nondeduced context. */
16914 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
16916 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
16919 processing_template_decl--;
16921 /* All things being equal, if the next argument is a pack expansion
16922 for one function but not for the other, prefer the
16923 non-variadic function. FIXME this is bogus; see c++/41958. */
16925 && args1 && TREE_VALUE (args1)
16926 && args2 && TREE_VALUE (args2))
16928 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
16929 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
16932 if (lose1 == lose2)
16940 /* Determine which of two partial specializations is more specialized.
16942 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
16943 to the first partial specialization. The TREE_VALUE is the
16944 innermost set of template parameters for the partial
16945 specialization. PAT2 is similar, but for the second template.
16947 Return 1 if the first partial specialization is more specialized;
16948 -1 if the second is more specialized; 0 if neither is more
16951 See [temp.class.order] for information about determining which of
16952 two templates is more specialized. */
16955 more_specialized_class (tree pat1, tree pat2)
16960 bool any_deductions = false;
16962 tmpl1 = TREE_TYPE (pat1);
16963 tmpl2 = TREE_TYPE (pat2);
16965 /* Just like what happens for functions, if we are ordering between
16966 different class template specializations, we may encounter dependent
16967 types in the arguments, and we need our dependency check functions
16968 to behave correctly. */
16969 ++processing_template_decl;
16970 targs = get_class_bindings (TREE_VALUE (pat1),
16971 CLASSTYPE_TI_ARGS (tmpl1),
16972 CLASSTYPE_TI_ARGS (tmpl2));
16976 any_deductions = true;
16979 targs = get_class_bindings (TREE_VALUE (pat2),
16980 CLASSTYPE_TI_ARGS (tmpl2),
16981 CLASSTYPE_TI_ARGS (tmpl1));
16985 any_deductions = true;
16987 --processing_template_decl;
16989 /* In the case of a tie where at least one of the class templates
16990 has a parameter pack at the end, the template with the most
16991 non-packed parameters wins. */
16994 && (template_args_variadic_p (TREE_PURPOSE (pat1))
16995 || template_args_variadic_p (TREE_PURPOSE (pat2))))
16997 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
16998 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
16999 int len1 = TREE_VEC_LENGTH (args1);
17000 int len2 = TREE_VEC_LENGTH (args2);
17002 /* We don't count the pack expansion at the end. */
17003 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17005 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17010 else if (len1 < len2)
17017 /* Return the template arguments that will produce the function signature
17018 DECL from the function template FN, with the explicit template
17019 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17020 also match. Return NULL_TREE if no satisfactory arguments could be
17024 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17026 int ntparms = DECL_NTPARMS (fn);
17027 tree targs = make_tree_vec (ntparms);
17029 tree decl_arg_types;
17031 unsigned int nargs, ix;
17034 /* Substitute the explicit template arguments into the type of DECL.
17035 The call to fn_type_unification will handle substitution into the
17037 decl_type = TREE_TYPE (decl);
17038 if (explicit_args && uses_template_parms (decl_type))
17041 tree converted_args;
17043 if (DECL_TEMPLATE_INFO (decl))
17044 tmpl = DECL_TI_TEMPLATE (decl);
17046 /* We can get here for some invalid specializations. */
17050 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17051 explicit_args, NULL_TREE,
17053 /*require_all_args=*/false,
17054 /*use_default_args=*/false);
17055 if (converted_args == error_mark_node)
17058 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17059 if (decl_type == error_mark_node)
17063 /* Never do unification on the 'this' parameter. */
17064 decl_arg_types = skip_artificial_parms_for (decl,
17065 TYPE_ARG_TYPES (decl_type));
17067 nargs = list_length (decl_arg_types);
17068 args = XALLOCAVEC (tree, nargs);
17069 for (arg = decl_arg_types, ix = 0;
17070 arg != NULL_TREE && arg != void_list_node;
17071 arg = TREE_CHAIN (arg), ++ix)
17072 args[ix] = TREE_VALUE (arg);
17074 if (fn_type_unification (fn, explicit_args, targs,
17076 (check_rettype || DECL_CONV_FN_P (fn)
17077 ? TREE_TYPE (decl_type) : NULL_TREE),
17078 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17084 /* Return the innermost template arguments that, when applied to a
17085 template specialization whose innermost template parameters are
17086 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17089 For example, suppose we have:
17091 template <class T, class U> struct S {};
17092 template <class T> struct S<T*, int> {};
17094 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17095 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17096 int}. The resulting vector will be {double}, indicating that `T'
17097 is bound to `double'. */
17100 get_class_bindings (tree tparms, tree spec_args, tree args)
17102 int i, ntparms = TREE_VEC_LENGTH (tparms);
17104 tree innermost_deduced_args;
17106 innermost_deduced_args = make_tree_vec (ntparms);
17107 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17109 deduced_args = copy_node (args);
17110 SET_TMPL_ARGS_LEVEL (deduced_args,
17111 TMPL_ARGS_DEPTH (deduced_args),
17112 innermost_deduced_args);
17115 deduced_args = innermost_deduced_args;
17117 if (unify (tparms, deduced_args,
17118 INNERMOST_TEMPLATE_ARGS (spec_args),
17119 INNERMOST_TEMPLATE_ARGS (args),
17120 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17123 for (i = 0; i < ntparms; ++i)
17124 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17127 /* Verify that nondeduced template arguments agree with the type
17128 obtained from argument deduction.
17132 struct A { typedef int X; };
17133 template <class T, class U> struct C {};
17134 template <class T> struct C<T, typename T::X> {};
17136 Then with the instantiation `C<A, int>', we can deduce that
17137 `T' is `A' but unify () does not check whether `typename T::X'
17139 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17140 if (spec_args == error_mark_node
17141 /* We only need to check the innermost arguments; the other
17142 arguments will always agree. */
17143 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17144 INNERMOST_TEMPLATE_ARGS (args)))
17147 /* Now that we have bindings for all of the template arguments,
17148 ensure that the arguments deduced for the template template
17149 parameters have compatible template parameter lists. See the use
17150 of template_template_parm_bindings_ok_p in fn_type_unification
17151 for more information. */
17152 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17155 return deduced_args;
17158 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17159 Return the TREE_LIST node with the most specialized template, if
17160 any. If there is no most specialized template, the error_mark_node
17163 Note that this function does not look at, or modify, the
17164 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17165 returned is one of the elements of INSTANTIATIONS, callers may
17166 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17167 and retrieve it from the value returned. */
17170 most_specialized_instantiation (tree templates)
17174 ++processing_template_decl;
17177 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17181 if (get_bindings (TREE_VALUE (champ),
17182 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17183 NULL_TREE, /*check_ret=*/true))
17186 if (get_bindings (TREE_VALUE (fn),
17187 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17188 NULL_TREE, /*check_ret=*/true))
17195 /* Equally specialized, move to next function. If there
17196 is no next function, nothing's most specialized. */
17197 fn = TREE_CHAIN (fn);
17205 /* Now verify that champ is better than everything earlier in the
17206 instantiation list. */
17207 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17208 if (get_bindings (TREE_VALUE (champ),
17209 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17210 NULL_TREE, /*check_ret=*/true)
17211 || !get_bindings (TREE_VALUE (fn),
17212 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17213 NULL_TREE, /*check_ret=*/true))
17219 processing_template_decl--;
17222 return error_mark_node;
17227 /* If DECL is a specialization of some template, return the most
17228 general such template. Otherwise, returns NULL_TREE.
17230 For example, given:
17232 template <class T> struct S { template <class U> void f(U); };
17234 if TMPL is `template <class U> void S<int>::f(U)' this will return
17235 the full template. This function will not trace past partial
17236 specializations, however. For example, given in addition:
17238 template <class T> struct S<T*> { template <class U> void f(U); };
17240 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17241 `template <class T> template <class U> S<T*>::f(U)'. */
17244 most_general_template (tree decl)
17246 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17247 an immediate specialization. */
17248 if (TREE_CODE (decl) == FUNCTION_DECL)
17250 if (DECL_TEMPLATE_INFO (decl)) {
17251 decl = DECL_TI_TEMPLATE (decl);
17253 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17254 template friend. */
17255 if (TREE_CODE (decl) != TEMPLATE_DECL)
17261 /* Look for more and more general templates. */
17262 while (DECL_TEMPLATE_INFO (decl))
17264 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17265 (See cp-tree.h for details.) */
17266 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17269 if (CLASS_TYPE_P (TREE_TYPE (decl))
17270 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17273 /* Stop if we run into an explicitly specialized class template. */
17274 if (!DECL_NAMESPACE_SCOPE_P (decl)
17275 && DECL_CONTEXT (decl)
17276 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17279 decl = DECL_TI_TEMPLATE (decl);
17285 /* Return the most specialized of the class template partial
17286 specializations of TMPL which can produce TYPE, a specialization of
17287 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17288 a _TYPE node corresponding to the partial specialization, while the
17289 TREE_PURPOSE is the set of template arguments that must be
17290 substituted into the TREE_TYPE in order to generate TYPE.
17292 If the choice of partial specialization is ambiguous, a diagnostic
17293 is issued, and the error_mark_node is returned. If there are no
17294 partial specializations of TMPL matching TYPE, then NULL_TREE is
17298 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17300 tree list = NULL_TREE;
17306 tree outer_args = NULL_TREE;
17308 tmpl = most_general_template (tmpl);
17309 args = CLASSTYPE_TI_ARGS (type);
17311 /* For determining which partial specialization to use, only the
17312 innermost args are interesting. */
17313 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17315 outer_args = strip_innermost_template_args (args, 1);
17316 args = INNERMOST_TEMPLATE_ARGS (args);
17319 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17321 tree partial_spec_args;
17323 tree parms = TREE_VALUE (t);
17325 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17327 ++processing_template_decl;
17333 /* Discard the outer levels of args, and then substitute in the
17334 template args from the enclosing class. */
17335 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17336 partial_spec_args = tsubst_template_args
17337 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17339 /* PARMS already refers to just the innermost parms, but the
17340 template parms in partial_spec_args had their levels lowered
17341 by tsubst, so we need to do the same for the parm list. We
17342 can't just tsubst the TREE_VEC itself, as tsubst wants to
17343 treat a TREE_VEC as an argument vector. */
17344 parms = copy_node (parms);
17345 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17346 TREE_VEC_ELT (parms, i) =
17347 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17351 partial_spec_args =
17352 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17353 add_to_template_args (outer_args,
17354 partial_spec_args),
17356 /*require_all_args=*/true,
17357 /*use_default_args=*/true);
17359 --processing_template_decl;
17361 if (partial_spec_args == error_mark_node)
17362 return error_mark_node;
17364 spec_args = get_class_bindings (parms,
17370 spec_args = add_to_template_args (outer_args, spec_args);
17371 list = tree_cons (spec_args, TREE_VALUE (t), list);
17372 TREE_TYPE (list) = TREE_TYPE (t);
17379 ambiguous_p = false;
17382 t = TREE_CHAIN (t);
17383 for (; t; t = TREE_CHAIN (t))
17385 fate = more_specialized_class (champ, t);
17392 t = TREE_CHAIN (t);
17395 ambiguous_p = true;
17404 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17406 fate = more_specialized_class (champ, t);
17409 ambiguous_p = true;
17417 char *spaces = NULL;
17418 if (!(complain & tf_error))
17419 return error_mark_node;
17420 error ("ambiguous class template instantiation for %q#T", type);
17421 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17422 for (t = list; t; t = TREE_CHAIN (t))
17424 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17425 spaces = spaces ? spaces : get_spaces (str);
17428 return error_mark_node;
17434 /* Explicitly instantiate DECL. */
17437 do_decl_instantiation (tree decl, tree storage)
17439 tree result = NULL_TREE;
17442 if (!decl || decl == error_mark_node)
17443 /* An error occurred, for which grokdeclarator has already issued
17444 an appropriate message. */
17446 else if (! DECL_LANG_SPECIFIC (decl))
17448 error ("explicit instantiation of non-template %q#D", decl);
17451 else if (TREE_CODE (decl) == VAR_DECL)
17453 /* There is an asymmetry here in the way VAR_DECLs and
17454 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17455 the latter, the DECL we get back will be marked as a
17456 template instantiation, and the appropriate
17457 DECL_TEMPLATE_INFO will be set up. This does not happen for
17458 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17459 should handle VAR_DECLs as it currently handles
17461 if (!DECL_CLASS_SCOPE_P (decl))
17463 error ("%qD is not a static data member of a class template", decl);
17466 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17467 if (!result || TREE_CODE (result) != VAR_DECL)
17469 error ("no matching template for %qD found", decl);
17472 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17474 error ("type %qT for explicit instantiation %qD does not match "
17475 "declared type %qT", TREE_TYPE (result), decl,
17480 else if (TREE_CODE (decl) != FUNCTION_DECL)
17482 error ("explicit instantiation of %q#D", decl);
17488 /* Check for various error cases. Note that if the explicit
17489 instantiation is valid the RESULT will currently be marked as an
17490 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17491 until we get here. */
17493 if (DECL_TEMPLATE_SPECIALIZATION (result))
17495 /* DR 259 [temp.spec].
17497 Both an explicit instantiation and a declaration of an explicit
17498 specialization shall not appear in a program unless the explicit
17499 instantiation follows a declaration of the explicit specialization.
17501 For a given set of template parameters, if an explicit
17502 instantiation of a template appears after a declaration of an
17503 explicit specialization for that template, the explicit
17504 instantiation has no effect. */
17507 else if (DECL_EXPLICIT_INSTANTIATION (result))
17511 No program shall explicitly instantiate any template more
17514 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17515 the first instantiation was `extern' and the second is not,
17516 and EXTERN_P for the opposite case. */
17517 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17518 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17519 /* If an "extern" explicit instantiation follows an ordinary
17520 explicit instantiation, the template is instantiated. */
17524 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17526 error ("no matching template for %qD found", result);
17529 else if (!DECL_TEMPLATE_INFO (result))
17531 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17535 if (storage == NULL_TREE)
17537 else if (storage == ridpointers[(int) RID_EXTERN])
17539 if (!in_system_header && (cxx_dialect == cxx98))
17540 pedwarn (input_location, OPT_pedantic,
17541 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17546 error ("storage class %qD applied to template instantiation", storage);
17548 check_explicit_instantiation_namespace (result);
17549 mark_decl_instantiated (result, extern_p);
17551 instantiate_decl (result, /*defer_ok=*/1,
17552 /*expl_inst_class_mem_p=*/false);
17556 mark_class_instantiated (tree t, int extern_p)
17558 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17559 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17560 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17561 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17564 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17565 rest_of_type_compilation (t, 1);
17569 /* Called from do_type_instantiation through binding_table_foreach to
17570 do recursive instantiation for the type bound in ENTRY. */
17572 bt_instantiate_type_proc (binding_entry entry, void *data)
17574 tree storage = *(tree *) data;
17576 if (MAYBE_CLASS_TYPE_P (entry->type)
17577 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17578 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17581 /* Called from do_type_instantiation to instantiate a member
17582 (a member function or a static member variable) of an
17583 explicitly instantiated class template. */
17585 instantiate_class_member (tree decl, int extern_p)
17587 mark_decl_instantiated (decl, extern_p);
17589 instantiate_decl (decl, /*defer_ok=*/1,
17590 /*expl_inst_class_mem_p=*/true);
17593 /* Perform an explicit instantiation of template class T. STORAGE, if
17594 non-null, is the RID for extern, inline or static. COMPLAIN is
17595 nonzero if this is called from the parser, zero if called recursively,
17596 since the standard is unclear (as detailed below). */
17599 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17604 int previous_instantiation_extern_p = 0;
17606 if (TREE_CODE (t) == TYPE_DECL)
17609 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17611 error ("explicit instantiation of non-template type %qT", t);
17617 if (!COMPLETE_TYPE_P (t))
17619 if (complain & tf_error)
17620 error ("explicit instantiation of %q#T before definition of template",
17625 if (storage != NULL_TREE)
17627 if (!in_system_header)
17629 if (storage == ridpointers[(int) RID_EXTERN])
17631 if (cxx_dialect == cxx98)
17632 pedwarn (input_location, OPT_pedantic,
17633 "ISO C++ 1998 forbids the use of %<extern%> on "
17634 "explicit instantiations");
17637 pedwarn (input_location, OPT_pedantic,
17638 "ISO C++ forbids the use of %qE"
17639 " on explicit instantiations", storage);
17642 if (storage == ridpointers[(int) RID_INLINE])
17644 else if (storage == ridpointers[(int) RID_EXTERN])
17646 else if (storage == ridpointers[(int) RID_STATIC])
17650 error ("storage class %qD applied to template instantiation",
17656 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
17658 /* DR 259 [temp.spec].
17660 Both an explicit instantiation and a declaration of an explicit
17661 specialization shall not appear in a program unless the explicit
17662 instantiation follows a declaration of the explicit specialization.
17664 For a given set of template parameters, if an explicit
17665 instantiation of a template appears after a declaration of an
17666 explicit specialization for that template, the explicit
17667 instantiation has no effect. */
17670 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
17674 No program shall explicitly instantiate any template more
17677 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
17678 instantiation was `extern'. If EXTERN_P then the second is.
17679 These cases are OK. */
17680 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
17682 if (!previous_instantiation_extern_p && !extern_p
17683 && (complain & tf_error))
17684 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
17686 /* If we've already instantiated the template, just return now. */
17687 if (!CLASSTYPE_INTERFACE_ONLY (t))
17691 check_explicit_instantiation_namespace (TYPE_NAME (t));
17692 mark_class_instantiated (t, extern_p);
17700 /* In contrast to implicit instantiation, where only the
17701 declarations, and not the definitions, of members are
17702 instantiated, we have here:
17706 The explicit instantiation of a class template specialization
17707 implies the instantiation of all of its members not
17708 previously explicitly specialized in the translation unit
17709 containing the explicit instantiation.
17711 Of course, we can't instantiate member template classes, since
17712 we don't have any arguments for them. Note that the standard
17713 is unclear on whether the instantiation of the members are
17714 *explicit* instantiations or not. However, the most natural
17715 interpretation is that it should be an explicit instantiation. */
17718 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
17719 if (TREE_CODE (tmp) == FUNCTION_DECL
17720 && DECL_TEMPLATE_INSTANTIATION (tmp))
17721 instantiate_class_member (tmp, extern_p);
17723 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
17724 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
17725 instantiate_class_member (tmp, extern_p);
17727 if (CLASSTYPE_NESTED_UTDS (t))
17728 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
17729 bt_instantiate_type_proc, &storage);
17733 /* Given a function DECL, which is a specialization of TMPL, modify
17734 DECL to be a re-instantiation of TMPL with the same template
17735 arguments. TMPL should be the template into which tsubst'ing
17736 should occur for DECL, not the most general template.
17738 One reason for doing this is a scenario like this:
17741 void f(const T&, int i);
17743 void g() { f(3, 7); }
17746 void f(const T& t, const int i) { }
17748 Note that when the template is first instantiated, with
17749 instantiate_template, the resulting DECL will have no name for the
17750 first parameter, and the wrong type for the second. So, when we go
17751 to instantiate the DECL, we regenerate it. */
17754 regenerate_decl_from_template (tree decl, tree tmpl)
17756 /* The arguments used to instantiate DECL, from the most general
17761 args = DECL_TI_ARGS (decl);
17762 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
17764 /* Make sure that we can see identifiers, and compute access
17766 push_access_scope (decl);
17768 if (TREE_CODE (decl) == FUNCTION_DECL)
17776 args_depth = TMPL_ARGS_DEPTH (args);
17777 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
17778 if (args_depth > parms_depth)
17779 args = get_innermost_template_args (args, parms_depth);
17781 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
17782 args, tf_error, NULL_TREE,
17783 /*defer_ok*/false);
17784 if (specs && specs != error_mark_node)
17785 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
17788 /* Merge parameter declarations. */
17789 decl_parm = skip_artificial_parms_for (decl,
17790 DECL_ARGUMENTS (decl));
17792 = skip_artificial_parms_for (code_pattern,
17793 DECL_ARGUMENTS (code_pattern));
17794 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
17799 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17800 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
17801 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
17803 parm_type = type_decays_to (parm_type);
17804 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17805 TREE_TYPE (decl_parm) = parm_type;
17806 attributes = DECL_ATTRIBUTES (pattern_parm);
17807 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17809 DECL_ATTRIBUTES (decl_parm) = attributes;
17810 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17812 decl_parm = DECL_CHAIN (decl_parm);
17813 pattern_parm = DECL_CHAIN (pattern_parm);
17815 /* Merge any parameters that match with the function parameter
17817 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
17820 tree expanded_types;
17821 /* Expand the TYPE_PACK_EXPANSION that provides the types for
17822 the parameters in this function parameter pack. */
17823 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
17824 args, tf_error, NULL_TREE);
17825 len = TREE_VEC_LENGTH (expanded_types);
17826 for (i = 0; i < len; i++)
17831 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
17832 /* Rename the parameter to include the index. */
17833 DECL_NAME (decl_parm) =
17834 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
17835 parm_type = TREE_VEC_ELT (expanded_types, i);
17836 parm_type = type_decays_to (parm_type);
17837 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
17838 TREE_TYPE (decl_parm) = parm_type;
17839 attributes = DECL_ATTRIBUTES (pattern_parm);
17840 if (DECL_ATTRIBUTES (decl_parm) != attributes)
17842 DECL_ATTRIBUTES (decl_parm) = attributes;
17843 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
17845 decl_parm = DECL_CHAIN (decl_parm);
17848 /* Merge additional specifiers from the CODE_PATTERN. */
17849 if (DECL_DECLARED_INLINE_P (code_pattern)
17850 && !DECL_DECLARED_INLINE_P (decl))
17851 DECL_DECLARED_INLINE_P (decl) = 1;
17853 else if (TREE_CODE (decl) == VAR_DECL)
17855 DECL_INITIAL (decl) =
17856 tsubst_expr (DECL_INITIAL (code_pattern), args,
17857 tf_error, DECL_TI_TEMPLATE (decl),
17858 /*integral_constant_expression_p=*/false);
17859 if (VAR_HAD_UNKNOWN_BOUND (decl))
17860 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
17861 tf_error, DECL_TI_TEMPLATE (decl));
17864 gcc_unreachable ();
17866 pop_access_scope (decl);
17869 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
17870 substituted to get DECL. */
17873 template_for_substitution (tree decl)
17875 tree tmpl = DECL_TI_TEMPLATE (decl);
17877 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
17878 for the instantiation. This is not always the most general
17879 template. Consider, for example:
17882 struct S { template <class U> void f();
17883 template <> void f<int>(); };
17885 and an instantiation of S<double>::f<int>. We want TD to be the
17886 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
17887 while (/* An instantiation cannot have a definition, so we need a
17888 more general template. */
17889 DECL_TEMPLATE_INSTANTIATION (tmpl)
17890 /* We must also deal with friend templates. Given:
17892 template <class T> struct S {
17893 template <class U> friend void f() {};
17896 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
17897 so far as the language is concerned, but that's still
17898 where we get the pattern for the instantiation from. On
17899 other hand, if the definition comes outside the class, say:
17901 template <class T> struct S {
17902 template <class U> friend void f();
17904 template <class U> friend void f() {}
17906 we don't need to look any further. That's what the check for
17907 DECL_INITIAL is for. */
17908 || (TREE_CODE (decl) == FUNCTION_DECL
17909 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
17910 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
17912 /* The present template, TD, should not be a definition. If it
17913 were a definition, we should be using it! Note that we
17914 cannot restructure the loop to just keep going until we find
17915 a template with a definition, since that might go too far if
17916 a specialization was declared, but not defined. */
17917 gcc_assert (TREE_CODE (decl) != VAR_DECL
17918 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
17920 /* Fetch the more general template. */
17921 tmpl = DECL_TI_TEMPLATE (tmpl);
17927 /* Returns true if we need to instantiate this template instance even if we
17928 know we aren't going to emit it.. */
17931 always_instantiate_p (tree decl)
17933 /* We always instantiate inline functions so that we can inline them. An
17934 explicit instantiation declaration prohibits implicit instantiation of
17935 non-inline functions. With high levels of optimization, we would
17936 normally inline non-inline functions -- but we're not allowed to do
17937 that for "extern template" functions. Therefore, we check
17938 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
17939 return ((TREE_CODE (decl) == FUNCTION_DECL
17940 && DECL_DECLARED_INLINE_P (decl))
17941 /* And we need to instantiate static data members so that
17942 their initializers are available in integral constant
17944 || (TREE_CODE (decl) == VAR_DECL
17945 && decl_maybe_constant_var_p (decl)));
17948 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
17949 instantiate it now, modifying TREE_TYPE (fn). */
17952 maybe_instantiate_noexcept (tree fn)
17954 tree fntype, spec, noex, clone;
17956 if (DECL_CLONED_FUNCTION_P (fn))
17957 fn = DECL_CLONED_FUNCTION (fn);
17958 fntype = TREE_TYPE (fn);
17959 spec = TYPE_RAISES_EXCEPTIONS (fntype);
17961 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
17964 noex = TREE_PURPOSE (spec);
17966 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
17968 push_tinst_level (fn);
17969 push_access_scope (fn);
17970 input_location = DECL_SOURCE_LOCATION (fn);
17971 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
17972 DEFERRED_NOEXCEPT_ARGS (noex),
17973 tf_warning_or_error, fn, /*function_p=*/false,
17974 /*integral_constant_expression_p=*/true);
17975 pop_access_scope (fn);
17976 pop_tinst_level ();
17977 spec = build_noexcept_spec (noex, tf_warning_or_error);
17978 if (spec == error_mark_node)
17979 spec = noexcept_false_spec;
17983 /* This is an implicitly declared function, so NOEX is a list of
17984 other functions to evaluate and merge. */
17986 spec = noexcept_true_spec;
17987 for (elt = noex; elt; elt = OVL_NEXT (elt))
17989 tree fn = OVL_CURRENT (elt);
17991 maybe_instantiate_noexcept (fn);
17992 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
17993 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
17997 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
17999 FOR_EACH_CLONE (clone, fn)
18001 if (TREE_TYPE (clone) == fntype)
18002 TREE_TYPE (clone) = TREE_TYPE (fn);
18004 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18008 /* Produce the definition of D, a _DECL generated from a template. If
18009 DEFER_OK is nonzero, then we don't have to actually do the
18010 instantiation now; we just have to do it sometime. Normally it is
18011 an error if this is an explicit instantiation but D is undefined.
18012 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18013 explicitly instantiated class template. */
18016 instantiate_decl (tree d, int defer_ok,
18017 bool expl_inst_class_mem_p)
18019 tree tmpl = DECL_TI_TEMPLATE (d);
18026 bool pattern_defined;
18028 location_t saved_loc = input_location;
18031 /* This function should only be used to instantiate templates for
18032 functions and static member variables. */
18033 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18034 || TREE_CODE (d) == VAR_DECL);
18036 /* Variables are never deferred; if instantiation is required, they
18037 are instantiated right away. That allows for better code in the
18038 case that an expression refers to the value of the variable --
18039 if the variable has a constant value the referring expression can
18040 take advantage of that fact. */
18041 if (TREE_CODE (d) == VAR_DECL
18042 || DECL_DECLARED_CONSTEXPR_P (d))
18045 /* Don't instantiate cloned functions. Instead, instantiate the
18046 functions they cloned. */
18047 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18048 d = DECL_CLONED_FUNCTION (d);
18050 if (DECL_TEMPLATE_INSTANTIATED (d)
18051 || (TREE_CODE (d) == FUNCTION_DECL
18052 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18053 || DECL_TEMPLATE_SPECIALIZATION (d))
18054 /* D has already been instantiated or explicitly specialized, so
18055 there's nothing for us to do here.
18057 It might seem reasonable to check whether or not D is an explicit
18058 instantiation, and, if so, stop here. But when an explicit
18059 instantiation is deferred until the end of the compilation,
18060 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18061 the instantiation. */
18064 /* Check to see whether we know that this template will be
18065 instantiated in some other file, as with "extern template"
18067 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18069 /* In general, we do not instantiate such templates. */
18070 if (external_p && !always_instantiate_p (d))
18073 gen_tmpl = most_general_template (tmpl);
18074 gen_args = DECL_TI_ARGS (d);
18076 if (tmpl != gen_tmpl)
18077 /* We should already have the extra args. */
18078 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18079 == TMPL_ARGS_DEPTH (gen_args));
18080 /* And what's in the hash table should match D. */
18081 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18082 || spec == NULL_TREE);
18084 /* This needs to happen before any tsubsting. */
18085 if (! push_tinst_level (d))
18088 timevar_push (TV_TEMPLATE_INST);
18090 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18091 for the instantiation. */
18092 td = template_for_substitution (d);
18093 code_pattern = DECL_TEMPLATE_RESULT (td);
18095 /* We should never be trying to instantiate a member of a class
18096 template or partial specialization. */
18097 gcc_assert (d != code_pattern);
18099 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18100 || DECL_TEMPLATE_SPECIALIZATION (td))
18101 /* In the case of a friend template whose definition is provided
18102 outside the class, we may have too many arguments. Drop the
18103 ones we don't need. The same is true for specializations. */
18104 args = get_innermost_template_args
18105 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18109 if (TREE_CODE (d) == FUNCTION_DECL)
18110 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18111 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18113 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18115 /* We may be in the middle of deferred access check. Disable it now. */
18116 push_deferring_access_checks (dk_no_deferred);
18118 /* Unless an explicit instantiation directive has already determined
18119 the linkage of D, remember that a definition is available for
18121 if (pattern_defined
18122 && !DECL_INTERFACE_KNOWN (d)
18123 && !DECL_NOT_REALLY_EXTERN (d))
18124 mark_definable (d);
18126 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18127 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18128 input_location = DECL_SOURCE_LOCATION (d);
18130 /* If D is a member of an explicitly instantiated class template,
18131 and no definition is available, treat it like an implicit
18133 if (!pattern_defined && expl_inst_class_mem_p
18134 && DECL_EXPLICIT_INSTANTIATION (d))
18136 /* Leave linkage flags alone on instantiations with anonymous
18138 if (TREE_PUBLIC (d))
18140 DECL_NOT_REALLY_EXTERN (d) = 0;
18141 DECL_INTERFACE_KNOWN (d) = 0;
18143 SET_DECL_IMPLICIT_INSTANTIATION (d);
18146 if (TREE_CODE (d) == FUNCTION_DECL)
18147 maybe_instantiate_noexcept (d);
18149 /* Recheck the substitutions to obtain any warning messages
18150 about ignoring cv qualifiers. Don't do this for artificial decls,
18151 as it breaks the context-sensitive substitution for lambda op(). */
18152 if (!defer_ok && !DECL_ARTIFICIAL (d))
18154 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18155 tree type = TREE_TYPE (gen);
18157 /* Make sure that we can see identifiers, and compute access
18158 correctly. D is already the target FUNCTION_DECL with the
18160 push_access_scope (d);
18162 if (TREE_CODE (gen) == FUNCTION_DECL)
18164 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18165 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18166 d, /*defer_ok*/true);
18167 /* Don't simply tsubst the function type, as that will give
18168 duplicate warnings about poor parameter qualifications.
18169 The function arguments are the same as the decl_arguments
18170 without the top level cv qualifiers. */
18171 type = TREE_TYPE (type);
18173 tsubst (type, gen_args, tf_warning_or_error, d);
18175 pop_access_scope (d);
18178 /* Defer all other templates, unless we have been explicitly
18179 forbidden from doing so. */
18180 if (/* If there is no definition, we cannot instantiate the
18183 /* If it's OK to postpone instantiation, do so. */
18185 /* If this is a static data member that will be defined
18186 elsewhere, we don't want to instantiate the entire data
18187 member, but we do want to instantiate the initializer so that
18188 we can substitute that elsewhere. */
18189 || (external_p && TREE_CODE (d) == VAR_DECL))
18191 /* The definition of the static data member is now required so
18192 we must substitute the initializer. */
18193 if (TREE_CODE (d) == VAR_DECL
18194 && !DECL_INITIAL (d)
18195 && DECL_INITIAL (code_pattern))
18199 bool const_init = false;
18201 ns = decl_namespace_context (d);
18202 push_nested_namespace (ns);
18203 push_nested_class (DECL_CONTEXT (d));
18204 init = tsubst_expr (DECL_INITIAL (code_pattern),
18206 tf_warning_or_error, NULL_TREE,
18207 /*integral_constant_expression_p=*/false);
18208 /* Make sure the initializer is still constant, in case of
18209 circular dependency (template/instantiate6.C). */
18211 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18212 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18213 /*asmspec_tree=*/NULL_TREE,
18214 LOOKUP_ONLYCONVERTING);
18215 pop_nested_class ();
18216 pop_nested_namespace (ns);
18219 /* We restore the source position here because it's used by
18220 add_pending_template. */
18221 input_location = saved_loc;
18223 if (at_eof && !pattern_defined
18224 && DECL_EXPLICIT_INSTANTIATION (d)
18225 && DECL_NOT_REALLY_EXTERN (d))
18228 The definition of a non-exported function template, a
18229 non-exported member function template, or a non-exported
18230 member function or static data member of a class template
18231 shall be present in every translation unit in which it is
18232 explicitly instantiated. */
18233 permerror (input_location, "explicit instantiation of %qD "
18234 "but no definition available", d);
18236 /* If we're in unevaluated context, we just wanted to get the
18237 constant value; this isn't an odr use, so don't queue
18238 a full instantiation. */
18239 if (cp_unevaluated_operand != 0)
18241 /* ??? Historically, we have instantiated inline functions, even
18242 when marked as "extern template". */
18243 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18244 add_pending_template (d);
18247 /* Tell the repository that D is available in this translation unit
18248 -- and see if it is supposed to be instantiated here. */
18249 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18251 /* In a PCH file, despite the fact that the repository hasn't
18252 requested instantiation in the PCH it is still possible that
18253 an instantiation will be required in a file that includes the
18256 add_pending_template (d);
18257 /* Instantiate inline functions so that the inliner can do its
18258 job, even though we'll not be emitting a copy of this
18260 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18264 need_push = !cfun || !global_bindings_p ();
18266 push_to_top_level ();
18268 /* Mark D as instantiated so that recursive calls to
18269 instantiate_decl do not try to instantiate it again. */
18270 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18272 /* Regenerate the declaration in case the template has been modified
18273 by a subsequent redeclaration. */
18274 regenerate_decl_from_template (d, td);
18276 /* We already set the file and line above. Reset them now in case
18277 they changed as a result of calling regenerate_decl_from_template. */
18278 input_location = DECL_SOURCE_LOCATION (d);
18280 if (TREE_CODE (d) == VAR_DECL)
18283 bool const_init = false;
18285 /* Clear out DECL_RTL; whatever was there before may not be right
18286 since we've reset the type of the declaration. */
18287 SET_DECL_RTL (d, NULL);
18288 DECL_IN_AGGR_P (d) = 0;
18290 /* The initializer is placed in DECL_INITIAL by
18291 regenerate_decl_from_template so we don't need to
18292 push/pop_access_scope again here. Pull it out so that
18293 cp_finish_decl can process it. */
18294 init = DECL_INITIAL (d);
18295 DECL_INITIAL (d) = NULL_TREE;
18296 DECL_INITIALIZED_P (d) = 0;
18298 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18299 initializer. That function will defer actual emission until
18300 we have a chance to determine linkage. */
18301 DECL_EXTERNAL (d) = 0;
18303 /* Enter the scope of D so that access-checking works correctly. */
18304 push_nested_class (DECL_CONTEXT (d));
18305 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18306 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18307 pop_nested_class ();
18309 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18310 synthesize_method (d);
18311 else if (TREE_CODE (d) == FUNCTION_DECL)
18313 htab_t saved_local_specializations;
18318 /* Save away the current list, in case we are instantiating one
18319 template from within the body of another. */
18320 saved_local_specializations = local_specializations;
18322 /* Set up the list of local specializations. */
18323 local_specializations = htab_create (37,
18324 hash_local_specialization,
18325 eq_local_specializations,
18328 /* Set up context. */
18329 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18331 /* Create substitution entries for the parameters. */
18332 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18333 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18334 spec_parm = DECL_ARGUMENTS (d);
18335 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18337 register_local_specialization (spec_parm, tmpl_parm);
18338 spec_parm = skip_artificial_parms_for (d, spec_parm);
18339 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18341 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18343 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18345 register_local_specialization (spec_parm, tmpl_parm);
18346 spec_parm = DECL_CHAIN (spec_parm);
18350 /* Register the (value) argument pack as a specialization of
18351 TMPL_PARM, then move on. */
18352 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18353 register_local_specialization (argpack, tmpl_parm);
18356 gcc_assert (!spec_parm);
18358 /* Substitute into the body of the function. */
18359 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18360 tf_warning_or_error, tmpl,
18361 /*integral_constant_expression_p=*/false);
18363 /* Set the current input_location to the end of the function
18364 so that finish_function knows where we are. */
18365 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18367 /* We don't need the local specializations any more. */
18368 htab_delete (local_specializations);
18369 local_specializations = saved_local_specializations;
18371 /* Finish the function. */
18372 d = finish_function (0);
18373 expand_or_defer_fn (d);
18376 /* We're not deferring instantiation any more. */
18377 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18380 pop_from_top_level ();
18383 input_location = saved_loc;
18384 pop_deferring_access_checks ();
18385 pop_tinst_level ();
18387 timevar_pop (TV_TEMPLATE_INST);
18392 /* Run through the list of templates that we wish we could
18393 instantiate, and instantiate any we can. RETRIES is the
18394 number of times we retry pending template instantiation. */
18397 instantiate_pending_templates (int retries)
18400 location_t saved_loc = input_location;
18402 /* Instantiating templates may trigger vtable generation. This in turn
18403 may require further template instantiations. We place a limit here
18404 to avoid infinite loop. */
18405 if (pending_templates && retries >= max_tinst_depth)
18407 tree decl = pending_templates->tinst->decl;
18409 error ("template instantiation depth exceeds maximum of %d"
18410 " instantiating %q+D, possibly from virtual table generation"
18411 " (use -ftemplate-depth= to increase the maximum)",
18412 max_tinst_depth, decl);
18413 if (TREE_CODE (decl) == FUNCTION_DECL)
18414 /* Pretend that we defined it. */
18415 DECL_INITIAL (decl) = error_mark_node;
18421 struct pending_template **t = &pending_templates;
18422 struct pending_template *last = NULL;
18426 tree instantiation = reopen_tinst_level ((*t)->tinst);
18427 bool complete = false;
18429 if (TYPE_P (instantiation))
18433 if (!COMPLETE_TYPE_P (instantiation))
18435 instantiate_class_template (instantiation);
18436 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18437 for (fn = TYPE_METHODS (instantiation);
18439 fn = TREE_CHAIN (fn))
18440 if (! DECL_ARTIFICIAL (fn))
18441 instantiate_decl (fn,
18443 /*expl_inst_class_mem_p=*/false);
18444 if (COMPLETE_TYPE_P (instantiation))
18448 complete = COMPLETE_TYPE_P (instantiation);
18452 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18453 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18456 = instantiate_decl (instantiation,
18458 /*expl_inst_class_mem_p=*/false);
18459 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18463 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18464 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18468 /* If INSTANTIATION has been instantiated, then we don't
18469 need to consider it again in the future. */
18477 current_tinst_level = NULL;
18479 last_pending_template = last;
18481 while (reconsider);
18483 input_location = saved_loc;
18486 /* Substitute ARGVEC into T, which is a list of initializers for
18487 either base class or a non-static data member. The TREE_PURPOSEs
18488 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18489 instantiate_decl. */
18492 tsubst_initializer_list (tree t, tree argvec)
18494 tree inits = NULL_TREE;
18496 for (; t; t = TREE_CHAIN (t))
18500 tree expanded_bases = NULL_TREE;
18501 tree expanded_arguments = NULL_TREE;
18504 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18509 /* Expand the base class expansion type into separate base
18511 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18512 tf_warning_or_error,
18514 if (expanded_bases == error_mark_node)
18517 /* We'll be building separate TREE_LISTs of arguments for
18519 len = TREE_VEC_LENGTH (expanded_bases);
18520 expanded_arguments = make_tree_vec (len);
18521 for (i = 0; i < len; i++)
18522 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18524 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18525 expand each argument in the TREE_VALUE of t. */
18526 expr = make_node (EXPR_PACK_EXPANSION);
18527 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18528 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18530 if (TREE_VALUE (t) == void_type_node)
18531 /* VOID_TYPE_NODE is used to indicate
18532 value-initialization. */
18534 for (i = 0; i < len; i++)
18535 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18539 /* Substitute parameter packs into each argument in the
18541 in_base_initializer = 1;
18542 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18544 tree expanded_exprs;
18546 /* Expand the argument. */
18547 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18549 = tsubst_pack_expansion (expr, argvec,
18550 tf_warning_or_error,
18552 if (expanded_exprs == error_mark_node)
18555 /* Prepend each of the expanded expressions to the
18556 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18557 for (i = 0; i < len; i++)
18559 TREE_VEC_ELT (expanded_arguments, i) =
18560 tree_cons (NULL_TREE,
18561 TREE_VEC_ELT (expanded_exprs, i),
18562 TREE_VEC_ELT (expanded_arguments, i));
18565 in_base_initializer = 0;
18567 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18568 since we built them backwards. */
18569 for (i = 0; i < len; i++)
18571 TREE_VEC_ELT (expanded_arguments, i) =
18572 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18577 for (i = 0; i < len; ++i)
18579 if (expanded_bases)
18581 decl = TREE_VEC_ELT (expanded_bases, i);
18582 decl = expand_member_init (decl);
18583 init = TREE_VEC_ELT (expanded_arguments, i);
18587 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18588 tf_warning_or_error, NULL_TREE);
18590 decl = expand_member_init (decl);
18591 if (decl && !DECL_P (decl))
18592 in_base_initializer = 1;
18594 init = TREE_VALUE (t);
18595 if (init != void_type_node)
18596 init = tsubst_expr (init, argvec,
18597 tf_warning_or_error, NULL_TREE,
18598 /*integral_constant_expression_p=*/false);
18599 in_base_initializer = 0;
18604 init = build_tree_list (decl, init);
18605 TREE_CHAIN (init) = inits;
18613 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18616 set_current_access_from_decl (tree decl)
18618 if (TREE_PRIVATE (decl))
18619 current_access_specifier = access_private_node;
18620 else if (TREE_PROTECTED (decl))
18621 current_access_specifier = access_protected_node;
18623 current_access_specifier = access_public_node;
18626 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
18627 is the instantiation (which should have been created with
18628 start_enum) and ARGS are the template arguments to use. */
18631 tsubst_enum (tree tag, tree newtag, tree args)
18635 if (SCOPED_ENUM_P (newtag))
18636 begin_scope (sk_scoped_enum, newtag);
18638 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
18643 decl = TREE_VALUE (e);
18644 /* Note that in a template enum, the TREE_VALUE is the
18645 CONST_DECL, not the corresponding INTEGER_CST. */
18646 value = tsubst_expr (DECL_INITIAL (decl),
18647 args, tf_warning_or_error, NULL_TREE,
18648 /*integral_constant_expression_p=*/true);
18650 /* Give this enumeration constant the correct access. */
18651 set_current_access_from_decl (decl);
18653 /* Actually build the enumerator itself. */
18655 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
18658 if (SCOPED_ENUM_P (newtag))
18661 finish_enum_value_list (newtag);
18662 finish_enum (newtag);
18664 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
18665 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
18668 /* DECL is a FUNCTION_DECL that is a template specialization. Return
18669 its type -- but without substituting the innermost set of template
18670 arguments. So, innermost set of template parameters will appear in
18674 get_mostly_instantiated_function_type (tree decl)
18682 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
18683 targs = DECL_TI_ARGS (decl);
18684 tparms = DECL_TEMPLATE_PARMS (tmpl);
18685 parm_depth = TMPL_PARMS_DEPTH (tparms);
18687 /* There should be as many levels of arguments as there are levels
18689 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
18691 fn_type = TREE_TYPE (tmpl);
18693 if (parm_depth == 1)
18694 /* No substitution is necessary. */
18701 /* Replace the innermost level of the TARGS with NULL_TREEs to
18702 let tsubst know not to substitute for those parameters. */
18703 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
18704 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
18705 SET_TMPL_ARGS_LEVEL (partial_args, i,
18706 TMPL_ARGS_LEVEL (targs, i));
18707 SET_TMPL_ARGS_LEVEL (partial_args,
18708 TMPL_ARGS_DEPTH (targs),
18709 make_tree_vec (DECL_NTPARMS (tmpl)));
18711 /* Make sure that we can see identifiers, and compute access
18713 push_access_scope (decl);
18715 ++processing_template_decl;
18716 /* Now, do the (partial) substitution to figure out the
18717 appropriate function type. */
18718 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
18719 --processing_template_decl;
18721 /* Substitute into the template parameters to obtain the real
18722 innermost set of parameters. This step is important if the
18723 innermost set of template parameters contains value
18724 parameters whose types depend on outer template parameters. */
18725 TREE_VEC_LENGTH (partial_args)--;
18726 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
18728 pop_access_scope (decl);
18734 /* Return truthvalue if we're processing a template different from
18735 the last one involved in diagnostics. */
18737 problematic_instantiation_changed (void)
18739 return current_tinst_level != last_error_tinst_level;
18742 /* Remember current template involved in diagnostics. */
18744 record_last_problematic_instantiation (void)
18746 last_error_tinst_level = current_tinst_level;
18749 struct tinst_level *
18750 current_instantiation (void)
18752 return current_tinst_level;
18755 /* [temp.param] Check that template non-type parm TYPE is of an allowable
18756 type. Return zero for ok, nonzero for disallowed. Issue error and
18757 warning messages under control of COMPLAIN. */
18760 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
18762 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
18764 else if (POINTER_TYPE_P (type))
18766 else if (TYPE_PTR_TO_MEMBER_P (type))
18768 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
18770 else if (TREE_CODE (type) == TYPENAME_TYPE)
18772 else if (TREE_CODE (type) == DECLTYPE_TYPE)
18774 else if (TREE_CODE (type) == NULLPTR_TYPE)
18777 if (complain & tf_error)
18778 error ("%q#T is not a valid type for a template constant parameter", type);
18782 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
18783 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
18786 dependent_type_p_r (tree type)
18792 A type is dependent if it is:
18794 -- a template parameter. Template template parameters are types
18795 for us (since TYPE_P holds true for them) so we handle
18797 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18798 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
18800 /* -- a qualified-id with a nested-name-specifier which contains a
18801 class-name that names a dependent type or whose unqualified-id
18802 names a dependent type. */
18803 if (TREE_CODE (type) == TYPENAME_TYPE)
18805 /* -- a cv-qualified type where the cv-unqualified type is
18807 type = TYPE_MAIN_VARIANT (type);
18808 /* -- a compound type constructed from any dependent type. */
18809 if (TYPE_PTR_TO_MEMBER_P (type))
18810 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
18811 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
18813 else if (TREE_CODE (type) == POINTER_TYPE
18814 || TREE_CODE (type) == REFERENCE_TYPE)
18815 return dependent_type_p (TREE_TYPE (type));
18816 else if (TREE_CODE (type) == FUNCTION_TYPE
18817 || TREE_CODE (type) == METHOD_TYPE)
18821 if (dependent_type_p (TREE_TYPE (type)))
18823 for (arg_type = TYPE_ARG_TYPES (type);
18825 arg_type = TREE_CHAIN (arg_type))
18826 if (dependent_type_p (TREE_VALUE (arg_type)))
18830 /* -- an array type constructed from any dependent type or whose
18831 size is specified by a constant expression that is
18834 We checked for type- and value-dependence of the bounds in
18835 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
18836 if (TREE_CODE (type) == ARRAY_TYPE)
18838 if (TYPE_DOMAIN (type)
18839 && dependent_type_p (TYPE_DOMAIN (type)))
18841 return dependent_type_p (TREE_TYPE (type));
18844 /* -- a template-id in which either the template name is a template
18846 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
18848 /* ... or any of the template arguments is a dependent type or
18849 an expression that is type-dependent or value-dependent. */
18850 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
18851 && (any_dependent_template_arguments_p
18852 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
18855 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
18856 dependent; if the argument of the `typeof' expression is not
18857 type-dependent, then it should already been have resolved. */
18858 if (TREE_CODE (type) == TYPEOF_TYPE
18859 || TREE_CODE (type) == DECLTYPE_TYPE
18860 || TREE_CODE (type) == UNDERLYING_TYPE)
18863 /* A template argument pack is dependent if any of its packed
18865 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
18867 tree args = ARGUMENT_PACK_ARGS (type);
18868 int i, len = TREE_VEC_LENGTH (args);
18869 for (i = 0; i < len; ++i)
18870 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
18874 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
18875 be template parameters. */
18876 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
18879 /* The standard does not specifically mention types that are local
18880 to template functions or local classes, but they should be
18881 considered dependent too. For example:
18883 template <int I> void f() {
18888 The size of `E' cannot be known until the value of `I' has been
18889 determined. Therefore, `E' must be considered dependent. */
18890 scope = TYPE_CONTEXT (type);
18891 if (scope && TYPE_P (scope))
18892 return dependent_type_p (scope);
18893 /* Don't use type_dependent_expression_p here, as it can lead
18894 to infinite recursion trying to determine whether a lambda
18895 nested in a lambda is dependent (c++/47687). */
18896 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
18897 && DECL_LANG_SPECIFIC (scope)
18898 && DECL_TEMPLATE_INFO (scope)
18899 && (any_dependent_template_arguments_p
18900 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
18903 /* Other types are non-dependent. */
18907 /* Returns TRUE if TYPE is dependent, in the sense of
18908 [temp.dep.type]. Note that a NULL type is considered dependent. */
18911 dependent_type_p (tree type)
18913 /* If there are no template parameters in scope, then there can't be
18914 any dependent types. */
18915 if (!processing_template_decl)
18917 /* If we are not processing a template, then nobody should be
18918 providing us with a dependent type. */
18920 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
18924 /* If the type is NULL, we have not computed a type for the entity
18925 in question; in that case, the type is dependent. */
18929 /* Erroneous types can be considered non-dependent. */
18930 if (type == error_mark_node)
18933 /* If we have not already computed the appropriate value for TYPE,
18935 if (!TYPE_DEPENDENT_P_VALID (type))
18937 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
18938 TYPE_DEPENDENT_P_VALID (type) = 1;
18941 return TYPE_DEPENDENT_P (type);
18944 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
18945 lookup. In other words, a dependent type that is not the current
18949 dependent_scope_p (tree scope)
18951 return (scope && TYPE_P (scope) && dependent_type_p (scope)
18952 && !currently_open_class (scope));
18955 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
18956 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
18959 /* Note that this predicate is not appropriate for general expressions;
18960 only constant expressions (that satisfy potential_constant_expression)
18961 can be tested for value dependence.
18963 We should really also have a predicate for "instantiation-dependent".
18965 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
18966 (what about instantiation-dependent constant-expressions?)
18967 is_late_template_attribute: defer if instantiation-dependent.
18968 compute_array_index_type: proceed if constant and not t- or v-dependent
18969 if instantiation-dependent, need to remember full expression
18970 uses_template_parms: FIXME - need to audit callers
18971 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
18972 dependent_type_p [array_type]: dependent if index type is dependent
18974 static_assert - instantiation-dependent */
18977 value_dependent_expression_p (tree expression)
18979 if (!processing_template_decl)
18982 /* A name declared with a dependent type. */
18983 if (DECL_P (expression) && type_dependent_expression_p (expression))
18986 switch (TREE_CODE (expression))
18988 case IDENTIFIER_NODE:
18989 /* A name that has not been looked up -- must be dependent. */
18992 case TEMPLATE_PARM_INDEX:
18993 /* A non-type template parm. */
18997 /* A non-type template parm. */
18998 if (DECL_TEMPLATE_PARM_P (expression))
19000 return value_dependent_expression_p (DECL_INITIAL (expression));
19003 /* A constant with literal type and is initialized
19004 with an expression that is value-dependent. */
19005 if (DECL_INITIAL (expression)
19006 && decl_constant_var_p (expression)
19007 && value_dependent_expression_p (DECL_INITIAL (expression)))
19011 case DYNAMIC_CAST_EXPR:
19012 case STATIC_CAST_EXPR:
19013 case CONST_CAST_EXPR:
19014 case REINTERPRET_CAST_EXPR:
19016 /* These expressions are value-dependent if the type to which
19017 the cast occurs is dependent or the expression being casted
19018 is value-dependent. */
19020 tree type = TREE_TYPE (expression);
19022 if (dependent_type_p (type))
19025 /* A functional cast has a list of operands. */
19026 expression = TREE_OPERAND (expression, 0);
19029 /* If there are no operands, it must be an expression such
19030 as "int()". This should not happen for aggregate types
19031 because it would form non-constant expressions. */
19032 gcc_assert (cxx_dialect >= cxx0x
19033 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19038 if (TREE_CODE (expression) == TREE_LIST)
19039 return any_value_dependent_elements_p (expression);
19041 return value_dependent_expression_p (expression);
19047 /* A `sizeof' expression is value-dependent if the operand is
19048 type-dependent or is a pack expansion. */
19049 expression = TREE_OPERAND (expression, 0);
19050 if (PACK_EXPANSION_P (expression))
19052 else if (TYPE_P (expression))
19053 return dependent_type_p (expression);
19054 return type_dependent_expression_p (expression);
19056 case AT_ENCODE_EXPR:
19057 /* An 'encode' expression is value-dependent if the operand is
19059 expression = TREE_OPERAND (expression, 0);
19060 return dependent_type_p (expression);
19062 case NOEXCEPT_EXPR:
19063 expression = TREE_OPERAND (expression, 0);
19064 return type_dependent_expression_p (expression);
19068 tree name = TREE_OPERAND (expression, 1);
19069 return value_dependent_expression_p (name);
19072 case COMPONENT_REF:
19073 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19074 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19076 case NONTYPE_ARGUMENT_PACK:
19077 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19078 is value-dependent. */
19080 tree values = ARGUMENT_PACK_ARGS (expression);
19081 int i, len = TREE_VEC_LENGTH (values);
19083 for (i = 0; i < len; ++i)
19084 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19092 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19093 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19094 || (type2 ? dependent_type_p (type2) : false));
19098 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19099 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19102 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19103 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19107 tree op = TREE_OPERAND (expression, 0);
19108 return (value_dependent_expression_p (op)
19109 || has_value_dependent_address (op));
19114 tree fn = get_callee_fndecl (expression);
19116 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19118 nargs = call_expr_nargs (expression);
19119 for (i = 0; i < nargs; ++i)
19121 tree op = CALL_EXPR_ARG (expression, i);
19122 /* In a call to a constexpr member function, look through the
19123 implicit ADDR_EXPR on the object argument so that it doesn't
19124 cause the call to be considered value-dependent. We also
19125 look through it in potential_constant_expression. */
19126 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19127 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19128 && TREE_CODE (op) == ADDR_EXPR)
19129 op = TREE_OPERAND (op, 0);
19130 if (value_dependent_expression_p (op))
19136 case TEMPLATE_ID_EXPR:
19137 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19139 return type_dependent_expression_p (expression);
19145 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19146 if (value_dependent_expression_p (val))
19152 /* A constant expression is value-dependent if any subexpression is
19153 value-dependent. */
19154 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19156 case tcc_reference:
19158 case tcc_comparison:
19160 case tcc_expression:
19163 int i, len = cp_tree_operand_length (expression);
19165 for (i = 0; i < len; i++)
19167 tree t = TREE_OPERAND (expression, i);
19169 /* In some cases, some of the operands may be missing.l
19170 (For example, in the case of PREDECREMENT_EXPR, the
19171 amount to increment by may be missing.) That doesn't
19172 make the expression dependent. */
19173 if (t && value_dependent_expression_p (t))
19184 /* The expression is not value-dependent. */
19188 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19189 [temp.dep.expr]. Note that an expression with no type is
19190 considered dependent. Other parts of the compiler arrange for an
19191 expression with type-dependent subexpressions to have no type, so
19192 this function doesn't have to be fully recursive. */
19195 type_dependent_expression_p (tree expression)
19197 if (!processing_template_decl)
19200 if (expression == error_mark_node)
19203 /* An unresolved name is always dependent. */
19204 if (TREE_CODE (expression) == IDENTIFIER_NODE
19205 || TREE_CODE (expression) == USING_DECL)
19208 /* Some expression forms are never type-dependent. */
19209 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19210 || TREE_CODE (expression) == SIZEOF_EXPR
19211 || TREE_CODE (expression) == ALIGNOF_EXPR
19212 || TREE_CODE (expression) == AT_ENCODE_EXPR
19213 || TREE_CODE (expression) == NOEXCEPT_EXPR
19214 || TREE_CODE (expression) == TRAIT_EXPR
19215 || TREE_CODE (expression) == TYPEID_EXPR
19216 || TREE_CODE (expression) == DELETE_EXPR
19217 || TREE_CODE (expression) == VEC_DELETE_EXPR
19218 || TREE_CODE (expression) == THROW_EXPR)
19221 /* The types of these expressions depends only on the type to which
19222 the cast occurs. */
19223 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19224 || TREE_CODE (expression) == STATIC_CAST_EXPR
19225 || TREE_CODE (expression) == CONST_CAST_EXPR
19226 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19227 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19228 || TREE_CODE (expression) == CAST_EXPR)
19229 return dependent_type_p (TREE_TYPE (expression));
19231 /* The types of these expressions depends only on the type created
19232 by the expression. */
19233 if (TREE_CODE (expression) == NEW_EXPR
19234 || TREE_CODE (expression) == VEC_NEW_EXPR)
19236 /* For NEW_EXPR tree nodes created inside a template, either
19237 the object type itself or a TREE_LIST may appear as the
19239 tree type = TREE_OPERAND (expression, 1);
19240 if (TREE_CODE (type) == TREE_LIST)
19241 /* This is an array type. We need to check array dimensions
19243 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19244 || value_dependent_expression_p
19245 (TREE_OPERAND (TREE_VALUE (type), 1));
19247 return dependent_type_p (type);
19250 if (TREE_CODE (expression) == SCOPE_REF)
19252 tree scope = TREE_OPERAND (expression, 0);
19253 tree name = TREE_OPERAND (expression, 1);
19255 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19256 contains an identifier associated by name lookup with one or more
19257 declarations declared with a dependent type, or...a
19258 nested-name-specifier or qualified-id that names a member of an
19259 unknown specialization. */
19260 return (type_dependent_expression_p (name)
19261 || dependent_scope_p (scope));
19264 if (TREE_CODE (expression) == FUNCTION_DECL
19265 && DECL_LANG_SPECIFIC (expression)
19266 && DECL_TEMPLATE_INFO (expression)
19267 && (any_dependent_template_arguments_p
19268 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19271 if (TREE_CODE (expression) == TEMPLATE_DECL
19272 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19275 if (TREE_CODE (expression) == STMT_EXPR)
19276 expression = stmt_expr_value_expr (expression);
19278 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19283 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19285 if (type_dependent_expression_p (elt))
19291 /* A static data member of the current instantiation with incomplete
19292 array type is type-dependent, as the definition and specializations
19293 can have different bounds. */
19294 if (TREE_CODE (expression) == VAR_DECL
19295 && DECL_CLASS_SCOPE_P (expression)
19296 && dependent_type_p (DECL_CONTEXT (expression))
19297 && VAR_HAD_UNKNOWN_BOUND (expression))
19300 if (TREE_TYPE (expression) == unknown_type_node)
19302 if (TREE_CODE (expression) == ADDR_EXPR)
19303 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19304 if (TREE_CODE (expression) == COMPONENT_REF
19305 || TREE_CODE (expression) == OFFSET_REF)
19307 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19309 expression = TREE_OPERAND (expression, 1);
19310 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19313 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19314 if (TREE_CODE (expression) == SCOPE_REF)
19317 if (BASELINK_P (expression))
19318 expression = BASELINK_FUNCTIONS (expression);
19320 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19322 if (any_dependent_template_arguments_p
19323 (TREE_OPERAND (expression, 1)))
19325 expression = TREE_OPERAND (expression, 0);
19327 gcc_assert (TREE_CODE (expression) == OVERLOAD
19328 || TREE_CODE (expression) == FUNCTION_DECL);
19332 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19334 expression = OVL_NEXT (expression);
19339 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19341 return (dependent_type_p (TREE_TYPE (expression)));
19344 /* Like type_dependent_expression_p, but it also works while not processing
19345 a template definition, i.e. during substitution or mangling. */
19348 type_dependent_expression_p_push (tree expr)
19351 ++processing_template_decl;
19352 b = type_dependent_expression_p (expr);
19353 --processing_template_decl;
19357 /* Returns TRUE if ARGS contains a type-dependent expression. */
19360 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19365 FOR_EACH_VEC_ELT (tree, args, i, arg)
19367 if (type_dependent_expression_p (arg))
19373 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19374 expressions) contains any type-dependent expressions. */
19377 any_type_dependent_elements_p (const_tree list)
19379 for (; list; list = TREE_CHAIN (list))
19380 if (value_dependent_expression_p (TREE_VALUE (list)))
19386 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19387 expressions) contains any value-dependent expressions. */
19390 any_value_dependent_elements_p (const_tree list)
19392 for (; list; list = TREE_CHAIN (list))
19393 if (value_dependent_expression_p (TREE_VALUE (list)))
19399 /* Returns TRUE if the ARG (a template argument) is dependent. */
19402 dependent_template_arg_p (tree arg)
19404 if (!processing_template_decl)
19407 /* Assume a template argument that was wrongly written by the user
19408 is dependent. This is consistent with what
19409 any_dependent_template_arguments_p [that calls this function]
19411 if (!arg || arg == error_mark_node)
19414 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19415 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19417 if (TREE_CODE (arg) == TEMPLATE_DECL
19418 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19419 return dependent_template_p (arg);
19420 else if (ARGUMENT_PACK_P (arg))
19422 tree args = ARGUMENT_PACK_ARGS (arg);
19423 int i, len = TREE_VEC_LENGTH (args);
19424 for (i = 0; i < len; ++i)
19426 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19432 else if (TYPE_P (arg))
19433 return dependent_type_p (arg);
19435 return (type_dependent_expression_p (arg)
19436 || value_dependent_expression_p (arg));
19439 /* Returns true if ARGS (a collection of template arguments) contains
19440 any types that require structural equality testing. */
19443 any_template_arguments_need_structural_equality_p (tree args)
19450 if (args == error_mark_node)
19453 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19455 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19456 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19458 tree arg = TREE_VEC_ELT (level, j);
19459 tree packed_args = NULL_TREE;
19462 if (ARGUMENT_PACK_P (arg))
19464 /* Look inside the argument pack. */
19465 packed_args = ARGUMENT_PACK_ARGS (arg);
19466 len = TREE_VEC_LENGTH (packed_args);
19469 for (k = 0; k < len; ++k)
19472 arg = TREE_VEC_ELT (packed_args, k);
19474 if (error_operand_p (arg))
19476 else if (TREE_CODE (arg) == TEMPLATE_DECL
19477 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19479 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19481 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19482 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19491 /* Returns true if ARGS (a collection of template arguments) contains
19492 any dependent arguments. */
19495 any_dependent_template_arguments_p (const_tree args)
19502 if (args == error_mark_node)
19505 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19507 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19508 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19509 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19516 /* Returns TRUE if the template TMPL is dependent. */
19519 dependent_template_p (tree tmpl)
19521 if (TREE_CODE (tmpl) == OVERLOAD)
19525 if (dependent_template_p (OVL_CURRENT (tmpl)))
19527 tmpl = OVL_NEXT (tmpl);
19532 /* Template template parameters are dependent. */
19533 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19534 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19536 /* So are names that have not been looked up. */
19537 if (TREE_CODE (tmpl) == SCOPE_REF
19538 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19540 /* So are member templates of dependent classes. */
19541 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19542 return dependent_type_p (DECL_CONTEXT (tmpl));
19546 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19549 dependent_template_id_p (tree tmpl, tree args)
19551 return (dependent_template_p (tmpl)
19552 || any_dependent_template_arguments_p (args));
19555 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19559 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19563 if (!processing_template_decl)
19566 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19568 tree decl = TREE_VEC_ELT (declv, i);
19569 tree init = TREE_VEC_ELT (initv, i);
19570 tree cond = TREE_VEC_ELT (condv, i);
19571 tree incr = TREE_VEC_ELT (incrv, i);
19573 if (type_dependent_expression_p (decl))
19576 if (init && type_dependent_expression_p (init))
19579 if (type_dependent_expression_p (cond))
19582 if (COMPARISON_CLASS_P (cond)
19583 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19584 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19587 if (TREE_CODE (incr) == MODOP_EXPR)
19589 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19590 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19593 else if (type_dependent_expression_p (incr))
19595 else if (TREE_CODE (incr) == MODIFY_EXPR)
19597 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19599 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19601 tree t = TREE_OPERAND (incr, 1);
19602 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19603 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19612 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19613 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
19614 no such TYPE can be found. Note that this function peers inside
19615 uninstantiated templates and therefore should be used only in
19616 extremely limited situations. ONLY_CURRENT_P restricts this
19617 peering to the currently open classes hierarchy (which is required
19618 when comparing types). */
19621 resolve_typename_type (tree type, bool only_current_p)
19630 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
19632 scope = TYPE_CONTEXT (type);
19633 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
19634 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
19635 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
19636 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
19637 identifier of the TYPENAME_TYPE anymore.
19638 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
19639 TYPENAME_TYPE instead, we avoid messing up with a possible
19640 typedef variant case. */
19641 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
19643 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
19644 it first before we can figure out what NAME refers to. */
19645 if (TREE_CODE (scope) == TYPENAME_TYPE)
19646 scope = resolve_typename_type (scope, only_current_p);
19647 /* If we don't know what SCOPE refers to, then we cannot resolve the
19649 if (TREE_CODE (scope) == TYPENAME_TYPE)
19651 /* If the SCOPE is a template type parameter, we have no way of
19652 resolving the name. */
19653 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
19655 /* If the SCOPE is not the current instantiation, there's no reason
19656 to look inside it. */
19657 if (only_current_p && !currently_open_class (scope))
19659 /* If this is a typedef, we don't want to look inside (c++/11987). */
19660 if (typedef_variant_p (type))
19662 /* If SCOPE isn't the template itself, it will not have a valid
19663 TYPE_FIELDS list. */
19664 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
19665 /* scope is either the template itself or a compatible instantiation
19666 like X<T>, so look up the name in the original template. */
19667 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
19669 /* scope is a partial instantiation, so we can't do the lookup or we
19670 will lose the template arguments. */
19672 /* Enter the SCOPE so that name lookup will be resolved as if we
19673 were in the class definition. In particular, SCOPE will no
19674 longer be considered a dependent type. */
19675 pushed_scope = push_scope (scope);
19676 /* Look up the declaration. */
19677 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
19679 result = NULL_TREE;
19681 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
19682 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
19685 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
19686 && TREE_CODE (decl) == TYPE_DECL)
19688 result = TREE_TYPE (decl);
19689 if (result == error_mark_node)
19690 result = NULL_TREE;
19692 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
19693 && DECL_CLASS_TEMPLATE_P (decl))
19697 /* Obtain the template and the arguments. */
19698 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
19699 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
19700 /* Instantiate the template. */
19701 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
19702 /*entering_scope=*/0,
19703 tf_error | tf_user);
19704 if (result == error_mark_node)
19705 result = NULL_TREE;
19708 /* Leave the SCOPE. */
19710 pop_scope (pushed_scope);
19712 /* If we failed to resolve it, return the original typename. */
19716 /* If lookup found a typename type, resolve that too. */
19717 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
19719 /* Ill-formed programs can cause infinite recursion here, so we
19720 must catch that. */
19721 TYPENAME_IS_RESOLVING_P (type) = 1;
19722 result = resolve_typename_type (result, only_current_p);
19723 TYPENAME_IS_RESOLVING_P (type) = 0;
19726 /* Qualify the resulting type. */
19727 quals = cp_type_quals (type);
19729 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
19734 /* EXPR is an expression which is not type-dependent. Return a proxy
19735 for EXPR that can be used to compute the types of larger
19736 expressions containing EXPR. */
19739 build_non_dependent_expr (tree expr)
19743 #ifdef ENABLE_CHECKING
19744 /* Try to get a constant value for all non-type-dependent expressions in
19745 order to expose bugs in *_dependent_expression_p and constexpr. */
19746 if (cxx_dialect >= cxx0x)
19747 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
19750 /* Preserve OVERLOADs; the functions must be available to resolve
19753 if (TREE_CODE (inner_expr) == STMT_EXPR)
19754 inner_expr = stmt_expr_value_expr (inner_expr);
19755 if (TREE_CODE (inner_expr) == ADDR_EXPR)
19756 inner_expr = TREE_OPERAND (inner_expr, 0);
19757 if (TREE_CODE (inner_expr) == COMPONENT_REF)
19758 inner_expr = TREE_OPERAND (inner_expr, 1);
19759 if (is_overloaded_fn (inner_expr)
19760 || TREE_CODE (inner_expr) == OFFSET_REF)
19762 /* There is no need to return a proxy for a variable. */
19763 if (TREE_CODE (expr) == VAR_DECL)
19765 /* Preserve string constants; conversions from string constants to
19766 "char *" are allowed, even though normally a "const char *"
19767 cannot be used to initialize a "char *". */
19768 if (TREE_CODE (expr) == STRING_CST)
19770 /* Preserve arithmetic constants, as an optimization -- there is no
19771 reason to create a new node. */
19772 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
19774 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
19775 There is at least one place where we want to know that a
19776 particular expression is a throw-expression: when checking a ?:
19777 expression, there are special rules if the second or third
19778 argument is a throw-expression. */
19779 if (TREE_CODE (expr) == THROW_EXPR)
19782 /* Don't wrap an initializer list, we need to be able to look inside. */
19783 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
19786 if (TREE_CODE (expr) == COND_EXPR)
19787 return build3 (COND_EXPR,
19789 TREE_OPERAND (expr, 0),
19790 (TREE_OPERAND (expr, 1)
19791 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
19792 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
19793 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
19794 if (TREE_CODE (expr) == COMPOUND_EXPR
19795 && !COMPOUND_EXPR_OVERLOADED (expr))
19796 return build2 (COMPOUND_EXPR,
19798 TREE_OPERAND (expr, 0),
19799 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
19801 /* If the type is unknown, it can't really be non-dependent */
19802 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
19804 /* Otherwise, build a NON_DEPENDENT_EXPR. */
19805 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
19808 /* ARGS is a vector of expressions as arguments to a function call.
19809 Replace the arguments with equivalent non-dependent expressions.
19810 This modifies ARGS in place. */
19813 make_args_non_dependent (VEC(tree,gc) *args)
19818 FOR_EACH_VEC_ELT (tree, args, ix, arg)
19820 tree newarg = build_non_dependent_expr (arg);
19822 VEC_replace (tree, args, ix, newarg);
19826 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
19827 with a level one deeper than the actual template parms. */
19832 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
19833 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
19834 TYPE_DECL, get_identifier ("auto"), au);
19835 TYPE_STUB_DECL (au) = TYPE_NAME (au);
19836 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
19837 (0, processing_template_decl + 1, processing_template_decl + 1,
19838 0, TYPE_NAME (au), NULL_TREE);
19839 TYPE_CANONICAL (au) = canonical_type_parameter (au);
19840 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
19841 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
19846 /* Given type ARG, return std::initializer_list<ARG>. */
19851 tree std_init_list = namespace_binding
19852 (get_identifier ("initializer_list"), std_node);
19854 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
19856 error ("deducing from brace-enclosed initializer list requires "
19857 "#include <initializer_list>");
19858 return error_mark_node;
19860 argvec = make_tree_vec (1);
19861 TREE_VEC_ELT (argvec, 0) = arg;
19862 return lookup_template_class (std_init_list, argvec, NULL_TREE,
19863 NULL_TREE, 0, tf_warning_or_error);
19866 /* Replace auto in TYPE with std::initializer_list<auto>. */
19869 listify_autos (tree type, tree auto_node)
19871 tree init_auto = listify (auto_node);
19872 tree argvec = make_tree_vec (1);
19873 TREE_VEC_ELT (argvec, 0) = init_auto;
19874 if (processing_template_decl)
19875 argvec = add_to_template_args (current_template_args (), argvec);
19876 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19879 /* walk_tree helper for do_auto_deduction. */
19882 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
19885 /* Is this a variable with the type we're looking for? */
19887 && TREE_TYPE (*tp) == type)
19893 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
19894 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
19897 do_auto_deduction (tree type, tree init, tree auto_node)
19899 tree parms, tparms, targs;
19904 if (processing_template_decl
19905 && (TREE_TYPE (init) == NULL_TREE
19906 || BRACE_ENCLOSED_INITIALIZER_P (init)))
19907 /* Not enough information to try this yet. */
19910 /* The name of the object being declared shall not appear in the
19911 initializer expression. */
19912 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
19915 error ("variable %q#D with %<auto%> type used in its own "
19916 "initializer", decl);
19917 return error_mark_node;
19920 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
19921 with either a new invented type template parameter U or, if the
19922 initializer is a braced-init-list (8.5.4), with
19923 std::initializer_list<U>. */
19924 if (BRACE_ENCLOSED_INITIALIZER_P (init))
19925 type = listify_autos (type, auto_node);
19927 init = resolve_nondeduced_context (init);
19929 parms = build_tree_list (NULL_TREE, type);
19931 tparms = make_tree_vec (1);
19932 targs = make_tree_vec (1);
19933 TREE_VEC_ELT (tparms, 0)
19934 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
19935 val = type_unification_real (tparms, targs, parms, args, 1, 0,
19936 DEDUCE_CALL, LOOKUP_NORMAL,
19937 /*explain_p=*/false);
19940 if (processing_template_decl)
19941 /* Try again at instantiation time. */
19943 if (type && type != error_mark_node)
19944 /* If type is error_mark_node a diagnostic must have been
19945 emitted by now. Also, having a mention to '<type error>'
19946 in the diagnostic is not really useful to the user. */
19947 error ("unable to deduce %qT from %qE", type, init);
19948 return error_mark_node;
19951 /* If the list of declarators contains more than one declarator, the type
19952 of each declared variable is determined as described above. If the
19953 type deduced for the template parameter U is not the same in each
19954 deduction, the program is ill-formed. */
19955 if (TREE_TYPE (auto_node)
19956 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
19958 error ("inconsistent deduction for %qT: %qT and then %qT",
19959 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
19960 return error_mark_node;
19962 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
19964 if (processing_template_decl)
19965 targs = add_to_template_args (current_template_args (), targs);
19966 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
19969 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
19973 splice_late_return_type (tree type, tree late_return_type)
19977 if (late_return_type == NULL_TREE)
19979 argvec = make_tree_vec (1);
19980 TREE_VEC_ELT (argvec, 0) = late_return_type;
19981 if (processing_template_parmlist)
19982 /* For a late-specified return type in a template type-parameter, we
19983 need to add a dummy argument level for its parmlist. */
19984 argvec = add_to_template_args
19985 (make_tree_vec (processing_template_parmlist), argvec);
19986 if (current_template_parms)
19987 argvec = add_to_template_args (current_template_args (), argvec);
19988 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
19991 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
19994 is_auto (const_tree type)
19996 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19997 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20003 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20004 appear as a type-specifier for the declaration in question, we don't
20005 have to look through the whole type. */
20008 type_uses_auto (tree type)
20010 enum tree_code code;
20011 if (is_auto (type))
20014 code = TREE_CODE (type);
20016 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20017 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20018 || code == METHOD_TYPE || code == ARRAY_TYPE)
20019 return type_uses_auto (TREE_TYPE (type));
20021 if (TYPE_PTRMEMFUNC_P (type))
20022 return type_uses_auto (TREE_TYPE (TREE_TYPE
20023 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20028 /* For a given template T, return the vector of typedefs referenced
20029 in T for which access check is needed at T instantiation time.
20030 T is either a FUNCTION_DECL or a RECORD_TYPE.
20031 Those typedefs were added to T by the function
20032 append_type_to_template_for_access_check. */
20034 VEC(qualified_typedef_usage_t,gc)*
20035 get_types_needing_access_check (tree t)
20038 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20040 if (!t || t == error_mark_node)
20043 if (!(ti = get_template_info (t)))
20046 if (CLASS_TYPE_P (t)
20047 || TREE_CODE (t) == FUNCTION_DECL)
20049 if (!TI_TEMPLATE (ti))
20052 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20058 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20059 tied to T. That list of typedefs will be access checked at
20060 T instantiation time.
20061 T is either a FUNCTION_DECL or a RECORD_TYPE.
20062 TYPE_DECL is a TYPE_DECL node representing a typedef.
20063 SCOPE is the scope through which TYPE_DECL is accessed.
20064 LOCATION is the location of the usage point of TYPE_DECL.
20066 This function is a subroutine of
20067 append_type_to_template_for_access_check. */
20070 append_type_to_template_for_access_check_1 (tree t,
20073 location_t location)
20075 qualified_typedef_usage_t typedef_usage;
20078 if (!t || t == error_mark_node)
20081 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20082 || CLASS_TYPE_P (t))
20084 && TREE_CODE (type_decl) == TYPE_DECL
20087 if (!(ti = get_template_info (t)))
20090 gcc_assert (TI_TEMPLATE (ti));
20092 typedef_usage.typedef_decl = type_decl;
20093 typedef_usage.context = scope;
20094 typedef_usage.locus = location;
20096 VEC_safe_push (qualified_typedef_usage_t, gc,
20097 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20101 /* Append TYPE_DECL to the template TEMPL.
20102 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20103 At TEMPL instanciation time, TYPE_DECL will be checked to see
20104 if it can be accessed through SCOPE.
20105 LOCATION is the location of the usage point of TYPE_DECL.
20107 e.g. consider the following code snippet:
20114 template<class U> struct S
20116 C::myint mi; // <-- usage point of the typedef C::myint
20121 At S<char> instantiation time, we need to check the access of C::myint
20122 In other words, we need to check the access of the myint typedef through
20123 the C scope. For that purpose, this function will add the myint typedef
20124 and the scope C through which its being accessed to a list of typedefs
20125 tied to the template S. That list will be walked at template instantiation
20126 time and access check performed on each typedefs it contains.
20127 Note that this particular code snippet should yield an error because
20128 myint is private to C. */
20131 append_type_to_template_for_access_check (tree templ,
20134 location_t location)
20136 qualified_typedef_usage_t *iter;
20139 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20141 /* Make sure we don't append the type to the template twice. */
20142 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20143 get_types_needing_access_check (templ),
20145 if (iter->typedef_decl == type_decl && scope == iter->context)
20148 append_type_to_template_for_access_check_1 (templ, type_decl,
20152 /* Set up the hash tables for template instantiations. */
20155 init_template_processing (void)
20157 decl_specializations = htab_create_ggc (37,
20158 hash_specialization,
20159 eq_specializations,
20161 type_specializations = htab_create_ggc (37,
20162 hash_specialization,
20163 eq_specializations,
20167 /* Print stats about the template hash tables for -fstats. */
20170 print_template_statistics (void)
20172 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20173 "%f collisions\n", (long) htab_size (decl_specializations),
20174 (long) htab_elements (decl_specializations),
20175 htab_collisions (decl_specializations));
20176 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20177 "%f collisions\n", (long) htab_size (type_specializations),
20178 (long) htab_elements (type_specializations),
20179 htab_collisions (type_specializations));
20182 #include "gt-cp-pt.h"