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
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"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
50 /* The type of functions taking a tree, and some additional data, and
52 typedef int (*tree_fn_t) (tree, void*);
54 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
55 instantiations have been deferred, either because their definitions
56 were not yet available, or because we were putting off doing the work. */
57 struct GTY (()) pending_template {
58 struct pending_template *next;
59 struct tinst_level *tinst;
62 static GTY(()) struct pending_template *pending_templates;
63 static GTY(()) struct pending_template *last_pending_template;
65 int processing_template_parmlist;
66 static int template_header_count;
68 static GTY(()) tree saved_trees;
69 static VEC(int,heap) *inline_parm_levels;
71 static GTY(()) struct tinst_level *current_tinst_level;
73 static GTY(()) tree saved_access_scope;
75 /* Live only within one (recursive) call to tsubst_expr. We use
76 this to pass the statement expression node from the STMT_EXPR
77 to the EXPR_STMT that is its result. */
78 static tree cur_stmt_expr;
80 /* A map from local variable declarations in the body of the template
81 presently being instantiated to the corresponding instantiated
83 static htab_t local_specializations;
85 typedef struct GTY(()) spec_entry
92 static GTY ((param_is (spec_entry)))
93 htab_t decl_specializations;
95 static GTY ((param_is (spec_entry)))
96 htab_t type_specializations;
98 /* Contains canonical template parameter types. The vector is indexed by
99 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
100 TREE_LIST, whose TREE_VALUEs contain the canonical template
101 parameters of various types and levels. */
102 static GTY(()) VEC(tree,gc) *canonical_template_parms;
104 #define UNIFY_ALLOW_NONE 0
105 #define UNIFY_ALLOW_MORE_CV_QUAL 1
106 #define UNIFY_ALLOW_LESS_CV_QUAL 2
107 #define UNIFY_ALLOW_DERIVED 4
108 #define UNIFY_ALLOW_INTEGER 8
109 #define UNIFY_ALLOW_OUTER_LEVEL 16
110 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
111 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
113 static void push_access_scope (tree);
114 static void pop_access_scope (tree);
115 static bool resolve_overloaded_unification (tree, tree, tree, tree,
116 unification_kind_t, int);
117 static int try_one_overload (tree, tree, tree, tree, tree,
118 unification_kind_t, int, bool);
119 static int unify (tree, tree, tree, tree, int);
120 static void add_pending_template (tree);
121 static int push_tinst_level (tree);
122 static void pop_tinst_level (void);
123 static tree reopen_tinst_level (struct tinst_level *);
124 static tree tsubst_initializer_list (tree, tree);
125 static tree get_class_bindings (tree, tree, tree);
126 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
128 static void tsubst_enum (tree, tree, tree);
129 static tree add_to_template_args (tree, tree);
130 static tree add_outermost_template_args (tree, tree);
131 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
132 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
134 static int type_unification_real (tree, tree, tree, const tree *,
135 unsigned int, int, unification_kind_t, int);
136 static void note_template_header (int);
137 static tree convert_nontype_argument_function (tree, tree);
138 static tree convert_nontype_argument (tree, tree);
139 static tree convert_template_argument (tree, tree, tree,
140 tsubst_flags_t, int, tree);
141 static int for_each_template_parm (tree, tree_fn_t, void*,
142 struct pointer_set_t*, bool);
143 static tree expand_template_argument_pack (tree);
144 static tree build_template_parm_index (int, int, int, tree, tree);
145 static bool inline_needs_template_parms (tree);
146 static void push_inline_template_parms_recursive (tree, int);
147 static tree retrieve_local_specialization (tree);
148 static void register_local_specialization (tree, tree);
149 static hashval_t hash_specialization (const void *p);
150 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
151 static int mark_template_parm (tree, void *);
152 static int template_parm_this_level_p (tree, void *);
153 static tree tsubst_friend_function (tree, tree);
154 static tree tsubst_friend_class (tree, tree);
155 static int can_complete_type_without_circularity (tree);
156 static tree get_bindings (tree, tree, tree, bool);
157 static int template_decl_level (tree);
158 static int check_cv_quals_for_unify (int, tree, tree);
159 static void template_parm_level_and_index (tree, int*, int*);
160 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
161 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
164 static void regenerate_decl_from_template (tree, tree);
165 static tree most_specialized_class (tree, tree);
166 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
167 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
169 static bool check_specialization_scope (void);
170 static tree process_partial_specialization (tree);
171 static void set_current_access_from_decl (tree);
172 static tree get_template_base (tree, tree, tree, tree);
173 static tree try_class_unification (tree, tree, tree, tree);
174 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
176 static bool template_template_parm_bindings_ok_p (tree, tree);
177 static int template_args_equal (tree, tree);
178 static void tsubst_default_arguments (tree);
179 static tree for_each_template_parm_r (tree *, int *, void *);
180 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
181 static void copy_default_args_to_explicit_spec (tree);
182 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
183 static int eq_local_specializations (const void *, const void *);
184 static bool dependent_template_arg_p (tree);
185 static bool any_template_arguments_need_structural_equality_p (tree);
186 static bool dependent_type_p_r (tree);
187 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
188 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
190 static tree tsubst_decl (tree, tree, tsubst_flags_t);
191 static void perform_typedefs_access_check (tree tmpl, tree targs);
192 static void append_type_to_template_for_access_check_1 (tree, tree, tree);
193 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
194 static tree listify (tree);
195 static tree listify_autos (tree, tree);
197 /* Make the current scope suitable for access checking when we are
198 processing T. T can be FUNCTION_DECL for instantiated function
199 template, or VAR_DECL for static member variable (need by
200 instantiate_decl). */
203 push_access_scope (tree t)
205 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
206 || TREE_CODE (t) == VAR_DECL);
208 if (DECL_FRIEND_CONTEXT (t))
209 push_nested_class (DECL_FRIEND_CONTEXT (t));
210 else if (DECL_CLASS_SCOPE_P (t))
211 push_nested_class (DECL_CONTEXT (t));
213 push_to_top_level ();
215 if (TREE_CODE (t) == FUNCTION_DECL)
217 saved_access_scope = tree_cons
218 (NULL_TREE, current_function_decl, saved_access_scope);
219 current_function_decl = t;
223 /* Restore the scope set up by push_access_scope. T is the node we
227 pop_access_scope (tree t)
229 if (TREE_CODE (t) == FUNCTION_DECL)
231 current_function_decl = TREE_VALUE (saved_access_scope);
232 saved_access_scope = TREE_CHAIN (saved_access_scope);
235 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
238 pop_from_top_level ();
241 /* Do any processing required when DECL (a member template
242 declaration) is finished. Returns the TEMPLATE_DECL corresponding
243 to DECL, unless it is a specialization, in which case the DECL
244 itself is returned. */
247 finish_member_template_decl (tree decl)
249 if (decl == error_mark_node)
250 return error_mark_node;
252 gcc_assert (DECL_P (decl));
254 if (TREE_CODE (decl) == TYPE_DECL)
258 type = TREE_TYPE (decl);
259 if (type == error_mark_node)
260 return error_mark_node;
261 if (MAYBE_CLASS_TYPE_P (type)
262 && CLASSTYPE_TEMPLATE_INFO (type)
263 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
265 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
266 check_member_template (tmpl);
271 else if (TREE_CODE (decl) == FIELD_DECL)
272 error ("data member %qD cannot be a member template", decl);
273 else if (DECL_TEMPLATE_INFO (decl))
275 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
277 check_member_template (DECL_TI_TEMPLATE (decl));
278 return DECL_TI_TEMPLATE (decl);
284 error ("invalid member template declaration %qD", decl);
286 return error_mark_node;
289 /* Return the template info node corresponding to T, whatever T is. */
292 get_template_info (const_tree t)
294 tree tinfo = NULL_TREE;
296 if (!t || t == error_mark_node)
299 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
300 tinfo = DECL_TEMPLATE_INFO (t);
302 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
305 if (TAGGED_TYPE_P (t))
306 tinfo = TYPE_TEMPLATE_INFO (t);
311 /* Returns the template nesting level of the indicated class TYPE.
321 A<T>::B<U> has depth two, while A<T> has depth one.
322 Both A<T>::B<int> and A<int>::B<U> have depth one, if
323 they are instantiations, not specializations.
325 This function is guaranteed to return 0 if passed NULL_TREE so
326 that, for example, `template_class_depth (current_class_type)' is
330 template_class_depth (tree type)
335 type && TREE_CODE (type) != NAMESPACE_DECL;
336 type = (TREE_CODE (type) == FUNCTION_DECL)
337 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
339 tree tinfo = get_template_info (type);
341 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
342 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
349 /* Subroutine of maybe_begin_member_template_processing.
350 Returns true if processing DECL needs us to push template parms. */
353 inline_needs_template_parms (tree decl)
355 if (! DECL_TEMPLATE_INFO (decl))
358 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
359 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
362 /* Subroutine of maybe_begin_member_template_processing.
363 Push the template parms in PARMS, starting from LEVELS steps into the
364 chain, and ending at the beginning, since template parms are listed
368 push_inline_template_parms_recursive (tree parmlist, int levels)
370 tree parms = TREE_VALUE (parmlist);
374 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
376 ++processing_template_decl;
377 current_template_parms
378 = tree_cons (size_int (processing_template_decl),
379 parms, current_template_parms);
380 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
382 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
384 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
386 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
388 if (parm == error_mark_node)
391 gcc_assert (DECL_P (parm));
393 switch (TREE_CODE (parm))
402 /* Make a CONST_DECL as is done in process_template_parm.
403 It is ugly that we recreate this here; the original
404 version built in process_template_parm is no longer
406 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
407 CONST_DECL, DECL_NAME (parm),
409 DECL_ARTIFICIAL (decl) = 1;
410 TREE_CONSTANT (decl) = 1;
411 TREE_READONLY (decl) = 1;
412 DECL_INITIAL (decl) = DECL_INITIAL (parm);
413 SET_DECL_TEMPLATE_PARM_P (decl);
424 /* Restore the template parameter context for a member template or
425 a friend template defined in a class definition. */
428 maybe_begin_member_template_processing (tree decl)
433 if (inline_needs_template_parms (decl))
435 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
436 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
438 if (DECL_TEMPLATE_SPECIALIZATION (decl))
441 parms = TREE_CHAIN (parms);
444 push_inline_template_parms_recursive (parms, levels);
447 /* Remember how many levels of template parameters we pushed so that
448 we can pop them later. */
449 VEC_safe_push (int, heap, inline_parm_levels, levels);
452 /* Undo the effects of maybe_begin_member_template_processing. */
455 maybe_end_member_template_processing (void)
460 if (VEC_length (int, inline_parm_levels) == 0)
463 last = VEC_pop (int, inline_parm_levels);
464 for (i = 0; i < last; ++i)
466 --processing_template_decl;
467 current_template_parms = TREE_CHAIN (current_template_parms);
472 /* Return a new template argument vector which contains all of ARGS,
473 but has as its innermost set of arguments the EXTRA_ARGS. */
476 add_to_template_args (tree args, tree extra_args)
483 extra_depth = TMPL_ARGS_DEPTH (extra_args);
484 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
486 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
487 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
489 for (j = 1; j <= extra_depth; ++j, ++i)
490 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
495 /* Like add_to_template_args, but only the outermost ARGS are added to
496 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
497 (EXTRA_ARGS) levels are added. This function is used to combine
498 the template arguments from a partial instantiation with the
499 template arguments used to attain the full instantiation from the
500 partial instantiation. */
503 add_outermost_template_args (tree args, tree extra_args)
507 /* If there are more levels of EXTRA_ARGS than there are ARGS,
508 something very fishy is going on. */
509 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
511 /* If *all* the new arguments will be the EXTRA_ARGS, just return
513 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
516 /* For the moment, we make ARGS look like it contains fewer levels. */
517 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
519 new_args = add_to_template_args (args, extra_args);
521 /* Now, we restore ARGS to its full dimensions. */
522 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
527 /* Return the N levels of innermost template arguments from the ARGS. */
530 get_innermost_template_args (tree args, int n)
538 /* If N is 1, just return the innermost set of template arguments. */
540 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
542 /* If we're not removing anything, just return the arguments we were
544 extra_levels = TMPL_ARGS_DEPTH (args) - n;
545 gcc_assert (extra_levels >= 0);
546 if (extra_levels == 0)
549 /* Make a new set of arguments, not containing the outer arguments. */
550 new_args = make_tree_vec (n);
551 for (i = 1; i <= n; ++i)
552 SET_TMPL_ARGS_LEVEL (new_args, i,
553 TMPL_ARGS_LEVEL (args, i + extra_levels));
558 /* The inverse of get_innermost_template_args: Return all but the innermost
559 EXTRA_LEVELS levels of template arguments from the ARGS. */
562 strip_innermost_template_args (tree args, int extra_levels)
565 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
570 /* If N is 1, just return the outermost set of template arguments. */
572 return TMPL_ARGS_LEVEL (args, 1);
574 /* If we're not removing anything, just return the arguments we were
576 gcc_assert (extra_levels >= 0);
577 if (extra_levels == 0)
580 /* Make a new set of arguments, not containing the inner 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));
589 /* We've got a template header coming up; push to a new level for storing
593 begin_template_parm_list (void)
595 /* We use a non-tag-transparent scope here, which causes pushtag to
596 put tags in this scope, rather than in the enclosing class or
597 namespace scope. This is the right thing, since we want
598 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
599 global template class, push_template_decl handles putting the
600 TEMPLATE_DECL into top-level scope. For a nested template class,
603 template <class T> struct S1 {
604 template <class T> struct S2 {};
607 pushtag contains special code to call pushdecl_with_scope on the
608 TEMPLATE_DECL for S2. */
609 begin_scope (sk_template_parms, NULL);
610 ++processing_template_decl;
611 ++processing_template_parmlist;
612 note_template_header (0);
615 /* This routine is called when a specialization is declared. If it is
616 invalid to declare a specialization here, an error is reported and
617 false is returned, otherwise this routine will return true. */
620 check_specialization_scope (void)
622 tree scope = current_scope ();
626 An explicit specialization shall be declared in the namespace of
627 which the template is a member, or, for member templates, in the
628 namespace of which the enclosing class or enclosing class
629 template is a member. An explicit specialization of a member
630 function, member class or static data member of a class template
631 shall be declared in the namespace of which the class template
633 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
635 error ("explicit specialization in non-namespace scope %qD", scope);
641 In an explicit specialization declaration for a member of a class
642 template or a member template that appears in namespace scope,
643 the member template and some of its enclosing class templates may
644 remain unspecialized, except that the declaration shall not
645 explicitly specialize a class member template if its enclosing
646 class templates are not explicitly specialized as well. */
647 if (current_template_parms)
649 error ("enclosing class templates are not explicitly specialized");
656 /* We've just seen template <>. */
659 begin_specialization (void)
661 begin_scope (sk_template_spec, NULL);
662 note_template_header (1);
663 return check_specialization_scope ();
666 /* Called at then end of processing a declaration preceded by
670 end_specialization (void)
673 reset_specialization ();
676 /* Any template <>'s that we have seen thus far are not referring to a
677 function specialization. */
680 reset_specialization (void)
682 processing_specialization = 0;
683 template_header_count = 0;
686 /* We've just seen a template header. If SPECIALIZATION is nonzero,
687 it was of the form template <>. */
690 note_template_header (int specialization)
692 processing_specialization = specialization;
693 template_header_count++;
696 /* We're beginning an explicit instantiation. */
699 begin_explicit_instantiation (void)
701 gcc_assert (!processing_explicit_instantiation);
702 processing_explicit_instantiation = true;
707 end_explicit_instantiation (void)
709 gcc_assert (processing_explicit_instantiation);
710 processing_explicit_instantiation = false;
713 /* An explicit specialization or partial specialization TMPL is being
714 declared. Check that the namespace in which the specialization is
715 occurring is permissible. Returns false iff it is invalid to
716 specialize TMPL in the current namespace. */
719 check_specialization_namespace (tree tmpl)
721 tree tpl_ns = decl_namespace_context (tmpl);
725 An explicit specialization shall be declared in the namespace of
726 which the template is a member, or, for member templates, in the
727 namespace of which the enclosing class or enclosing class
728 template is a member. An explicit specialization of a member
729 function, member class or static data member of a class template
730 shall be declared in the namespace of which the class template is
732 if (is_associated_namespace (current_namespace, tpl_ns))
733 /* Same or super-using namespace. */
737 permerror (input_location, "specialization of %qD in different namespace", tmpl);
738 permerror (input_location, " from definition of %q+#D", tmpl);
743 /* SPEC is an explicit instantiation. Check that it is valid to
744 perform this explicit instantiation in the current namespace. */
747 check_explicit_instantiation_namespace (tree spec)
751 /* DR 275: An explicit instantiation shall appear in an enclosing
752 namespace of its template. */
753 ns = decl_namespace_context (spec);
754 if (!is_ancestor (current_namespace, ns))
755 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
756 "(which does not enclose namespace %qD)",
757 spec, current_namespace, ns);
760 /* The TYPE is being declared. If it is a template type, that means it
761 is a partial specialization. Do appropriate error-checking. */
764 maybe_process_partial_specialization (tree type)
768 if (type == error_mark_node)
769 return error_mark_node;
771 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
773 error ("name of class shadows template template parameter %qD",
775 return error_mark_node;
778 context = TYPE_CONTEXT (type);
780 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
782 /* This is for ordinary explicit specialization and partial
783 specialization of a template class such as:
785 template <> class C<int>;
789 template <class T> class C<T*>;
791 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
793 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
794 && !COMPLETE_TYPE_P (type))
796 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
797 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
798 if (processing_template_decl)
800 if (push_template_decl (TYPE_MAIN_DECL (type))
802 return error_mark_node;
805 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
806 error ("specialization of %qT after instantiation", type);
808 else if (CLASS_TYPE_P (type)
809 && !CLASSTYPE_USE_TEMPLATE (type)
810 && CLASSTYPE_TEMPLATE_INFO (type)
811 && context && CLASS_TYPE_P (context)
812 && CLASSTYPE_TEMPLATE_INFO (context))
814 /* This is for an explicit specialization of member class
815 template according to [temp.expl.spec/18]:
817 template <> template <class U> class C<int>::D;
819 The context `C<int>' must be an implicit instantiation.
820 Otherwise this is just a member class template declared
823 template <> class C<int> { template <class U> class D; };
824 template <> template <class U> class C<int>::D;
826 In the first case, `C<int>::D' is a specialization of `C<T>::D'
827 while in the second case, `C<int>::D' is a primary template
828 and `C<T>::D' may not exist. */
830 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
831 && !COMPLETE_TYPE_P (type))
834 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
836 if (current_namespace
837 != decl_namespace_context (tmpl))
839 permerror (input_location, "specializing %q#T in different namespace", type);
840 permerror (input_location, " from definition of %q+#D", tmpl);
843 /* Check for invalid specialization after instantiation:
845 template <> template <> class C<int>::D<int>;
846 template <> template <class U> class C<int>::D; */
848 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
849 t; t = TREE_CHAIN (t))
851 tree inst = TREE_VALUE (t);
852 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
854 /* We already have a full specialization of this partial
855 instantiation. Reassign it to the new member
856 specialization template. */
860 elt.tmpl = most_general_template (tmpl);
861 elt.args = CLASSTYPE_TI_ARGS (inst);
864 htab_remove_elt (type_specializations, &elt);
867 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
869 slot = (spec_entry **)
870 htab_find_slot (type_specializations, &elt, INSERT);
871 *slot = GGC_NEW (spec_entry);
874 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
875 /* But if we've had an implicit instantiation, that's a
876 problem ([temp.expl.spec]/6). */
877 error ("specialization %qT after instantiation %qT",
881 /* Mark TYPE as a specialization. And as a result, we only
882 have one level of template argument for the innermost
884 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
885 CLASSTYPE_TI_ARGS (type)
886 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
889 else if (processing_specialization)
891 error ("explicit specialization of non-template %qT", type);
892 return error_mark_node;
898 /* Returns nonzero if we can optimize the retrieval of specializations
899 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
900 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
903 optimize_specialization_lookup_p (tree tmpl)
905 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
906 && DECL_CLASS_SCOPE_P (tmpl)
907 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
909 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
910 /* The optimized lookup depends on the fact that the
911 template arguments for the member function template apply
912 purely to the containing class, which is not true if the
913 containing class is an explicit or partial
915 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
916 && !DECL_MEMBER_TEMPLATE_P (tmpl)
917 && !DECL_CONV_FN_P (tmpl)
918 /* It is possible to have a template that is not a member
919 template and is not a member of a template class:
921 template <typename T>
922 struct S { friend A::f(); };
924 Here, the friend function is a template, but the context does
925 not have template information. The optimized lookup relies
926 on having ARGS be the template arguments for both the class
927 and the function template. */
928 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
931 /* Retrieve the specialization (in the sense of [temp.spec] - a
932 specialization is either an instantiation or an explicit
933 specialization) of TMPL for the given template ARGS. If there is
934 no such specialization, return NULL_TREE. The ARGS are a vector of
935 arguments, or a vector of vectors of arguments, in the case of
936 templates with more than one level of parameters.
938 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
939 then we search for a partial specialization matching ARGS. This
940 parameter is ignored if TMPL is not a class template. */
943 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
945 if (args == error_mark_node)
948 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
950 /* There should be as many levels of arguments as there are
951 levels of parameters. */
952 gcc_assert (TMPL_ARGS_DEPTH (args)
953 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
955 if (optimize_specialization_lookup_p (tmpl))
958 tree class_specialization;
959 VEC(tree,gc) *methods;
963 /* The template arguments actually apply to the containing
964 class. Find the class specialization with those
966 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
968 = retrieve_specialization (class_template, args, 0);
969 if (!class_specialization)
971 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
972 for the specialization. */
973 idx = class_method_index_for_fn (class_specialization, tmpl);
976 /* Iterate through the methods with the indicated name, looking
977 for the one that has an instance of TMPL. */
978 methods = CLASSTYPE_METHOD_VEC (class_specialization);
979 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
981 tree fn = OVL_CURRENT (fns);
982 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
983 /* using-declarations can add base methods to the method vec,
984 and we don't want those here. */
985 && DECL_CONTEXT (fn) == class_specialization)
994 htab_t specializations;
998 elt.spec = NULL_TREE;
1000 if (DECL_CLASS_TEMPLATE_P (tmpl))
1001 specializations = type_specializations;
1003 specializations = decl_specializations;
1006 hash = hash_specialization (&elt);
1007 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1015 /* Like retrieve_specialization, but for local declarations. */
1018 retrieve_local_specialization (tree tmpl)
1022 if (local_specializations == NULL)
1025 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1026 htab_hash_pointer (tmpl));
1027 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1030 /* Returns nonzero iff DECL is a specialization of TMPL. */
1033 is_specialization_of (tree decl, tree tmpl)
1037 if (TREE_CODE (decl) == FUNCTION_DECL)
1041 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1047 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1049 for (t = TREE_TYPE (decl);
1051 t = CLASSTYPE_USE_TEMPLATE (t)
1052 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1053 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1060 /* Returns nonzero iff DECL is a specialization of friend declaration
1061 FRIEND_DECL according to [temp.friend]. */
1064 is_specialization_of_friend (tree decl, tree friend_decl)
1066 bool need_template = true;
1069 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1070 || TREE_CODE (decl) == TYPE_DECL);
1072 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1073 of a template class, we want to check if DECL is a specialization
1075 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1076 && DECL_TEMPLATE_INFO (friend_decl)
1077 && !DECL_USE_TEMPLATE (friend_decl))
1079 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1080 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1081 need_template = false;
1083 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1084 && !PRIMARY_TEMPLATE_P (friend_decl))
1085 need_template = false;
1087 /* There is nothing to do if this is not a template friend. */
1088 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1091 if (is_specialization_of (decl, friend_decl))
1095 A member of a class template may be declared to be a friend of a
1096 non-template class. In this case, the corresponding member of
1097 every specialization of the class template is a friend of the
1098 class granting friendship.
1100 For example, given a template friend declaration
1102 template <class T> friend void A<T>::f();
1104 the member function below is considered a friend
1106 template <> struct A<int> {
1110 For this type of template friend, TEMPLATE_DEPTH below will be
1111 nonzero. To determine if DECL is a friend of FRIEND, we first
1112 check if the enclosing class is a specialization of another. */
1114 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1116 && DECL_CLASS_SCOPE_P (decl)
1117 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1118 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1120 /* Next, we check the members themselves. In order to handle
1121 a few tricky cases, such as when FRIEND_DECL's are
1123 template <class T> friend void A<T>::g(T t);
1124 template <class T> template <T t> friend void A<T>::h();
1128 void A<int>::g(int);
1129 template <int> void A<int>::h();
1131 we need to figure out ARGS, the template arguments from
1132 the context of DECL. This is required for template substitution
1133 of `T' in the function parameter of `g' and template parameter
1134 of `h' in the above examples. Here ARGS corresponds to `int'. */
1136 tree context = DECL_CONTEXT (decl);
1137 tree args = NULL_TREE;
1138 int current_depth = 0;
1140 while (current_depth < template_depth)
1142 if (CLASSTYPE_TEMPLATE_INFO (context))
1144 if (current_depth == 0)
1145 args = TYPE_TI_ARGS (context);
1147 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1150 context = TYPE_CONTEXT (context);
1153 if (TREE_CODE (decl) == FUNCTION_DECL)
1158 tree friend_args_type;
1159 tree decl_args_type;
1161 /* Make sure that both DECL and FRIEND_DECL are templates or
1163 is_template = DECL_TEMPLATE_INFO (decl)
1164 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1165 if (need_template ^ is_template)
1167 else if (is_template)
1169 /* If both are templates, check template parameter list. */
1171 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1173 if (!comp_template_parms
1174 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1178 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1181 decl_type = TREE_TYPE (decl);
1183 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1184 tf_none, NULL_TREE);
1185 if (friend_type == error_mark_node)
1188 /* Check if return types match. */
1189 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1192 /* Check if function parameter types match, ignoring the
1193 `this' parameter. */
1194 friend_args_type = TYPE_ARG_TYPES (friend_type);
1195 decl_args_type = TYPE_ARG_TYPES (decl_type);
1196 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1197 friend_args_type = TREE_CHAIN (friend_args_type);
1198 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1199 decl_args_type = TREE_CHAIN (decl_args_type);
1201 return compparms (decl_args_type, friend_args_type);
1205 /* DECL is a TYPE_DECL */
1207 tree decl_type = TREE_TYPE (decl);
1209 /* Make sure that both DECL and FRIEND_DECL are templates or
1212 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1213 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1215 if (need_template ^ is_template)
1217 else if (is_template)
1220 /* If both are templates, check the name of the two
1221 TEMPLATE_DECL's first because is_friend didn't. */
1222 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1223 != DECL_NAME (friend_decl))
1226 /* Now check template parameter list. */
1228 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1230 return comp_template_parms
1231 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1235 return (DECL_NAME (decl)
1236 == DECL_NAME (friend_decl));
1242 /* Register the specialization SPEC as a specialization of TMPL with
1243 the indicated ARGS. IS_FRIEND indicates whether the specialization
1244 is actually just a friend declaration. Returns SPEC, or an
1245 equivalent prior declaration, if available. */
1248 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1252 spec_entry **slot = NULL;
1255 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1257 if (TREE_CODE (spec) == FUNCTION_DECL
1258 && uses_template_parms (DECL_TI_ARGS (spec)))
1259 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1260 register it; we want the corresponding TEMPLATE_DECL instead.
1261 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1262 the more obvious `uses_template_parms (spec)' to avoid problems
1263 with default function arguments. In particular, given
1264 something like this:
1266 template <class T> void f(T t1, T t = T())
1268 the default argument expression is not substituted for in an
1269 instantiation unless and until it is actually needed. */
1272 if (optimize_specialization_lookup_p (tmpl))
1273 /* We don't put these specializations in the hash table, but we might
1274 want to give an error about a mismatch. */
1275 fn = retrieve_specialization (tmpl, args, 0);
1283 hash = hash_specialization (&elt);
1285 slot = (spec_entry **)
1286 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1293 /* We can sometimes try to re-register a specialization that we've
1294 already got. In particular, regenerate_decl_from_template calls
1295 duplicate_decls which will update the specialization list. But,
1296 we'll still get called again here anyhow. It's more convenient
1297 to simply allow this than to try to prevent it. */
1300 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1302 if (DECL_TEMPLATE_INSTANTIATION (fn))
1304 if (DECL_ODR_USED (fn)
1305 || DECL_EXPLICIT_INSTANTIATION (fn))
1307 error ("specialization of %qD after instantiation",
1309 return error_mark_node;
1314 /* This situation should occur only if the first
1315 specialization is an implicit instantiation, the
1316 second is an explicit specialization, and the
1317 implicit instantiation has not yet been used. That
1318 situation can occur if we have implicitly
1319 instantiated a member function and then specialized
1322 We can also wind up here if a friend declaration that
1323 looked like an instantiation turns out to be a
1326 template <class T> void foo(T);
1327 class S { friend void foo<>(int) };
1328 template <> void foo(int);
1330 We transform the existing DECL in place so that any
1331 pointers to it become pointers to the updated
1334 If there was a definition for the template, but not
1335 for the specialization, we want this to look as if
1336 there were no definition, and vice versa. */
1337 DECL_INITIAL (fn) = NULL_TREE;
1338 duplicate_decls (spec, fn, is_friend);
1339 /* The call to duplicate_decls will have applied
1342 An explicit specialization of a function template
1343 is inline only if it is explicitly declared to be,
1344 and independently of whether its function template
1347 to the primary function; now copy the inline bits to
1348 the various clones. */
1349 FOR_EACH_CLONE (clone, fn)
1351 DECL_DECLARED_INLINE_P (clone)
1352 = DECL_DECLARED_INLINE_P (fn);
1353 DECL_SOURCE_LOCATION (clone)
1354 = DECL_SOURCE_LOCATION (fn);
1356 check_specialization_namespace (fn);
1361 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1363 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1364 /* Dup decl failed, but this is a new definition. Set the
1365 line number so any errors match this new
1367 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1373 return duplicate_decls (spec, fn, is_friend);
1375 /* A specialization must be declared in the same namespace as the
1376 template it is specializing. */
1377 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1378 && !check_specialization_namespace (tmpl))
1379 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1381 if (!optimize_specialization_lookup_p (tmpl))
1383 gcc_assert (tmpl && args && spec);
1384 *slot = GGC_NEW (spec_entry);
1386 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1387 && PRIMARY_TEMPLATE_P (tmpl)
1388 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1389 /* TMPL is a forward declaration of a template function; keep a list
1390 of all specializations in case we need to reassign them to a friend
1391 template later in tsubst_friend_function. */
1392 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1393 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1399 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1400 TMPL and ARGS members, ignores SPEC. */
1403 eq_specializations (const void *p1, const void *p2)
1405 const spec_entry *e1 = (const spec_entry *)p1;
1406 const spec_entry *e2 = (const spec_entry *)p2;
1408 return (e1->tmpl == e2->tmpl
1409 && comp_template_args (e1->args, e2->args));
1412 /* Returns a hash for a template TMPL and template arguments ARGS. */
1415 hash_tmpl_and_args (tree tmpl, tree args)
1417 hashval_t val = DECL_UID (tmpl);
1418 return iterative_hash_template_arg (args, val);
1421 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1425 hash_specialization (const void *p)
1427 const spec_entry *e = (const spec_entry *)p;
1428 return hash_tmpl_and_args (e->tmpl, e->args);
1431 /* Recursively calculate a hash value for a template argument ARG, for use
1432 in the hash tables of template specializations. */
1435 iterative_hash_template_arg (tree arg, hashval_t val)
1437 unsigned HOST_WIDE_INT i;
1438 enum tree_code code;
1441 if (arg == NULL_TREE)
1442 return iterative_hash_object (arg, val);
1447 code = TREE_CODE (arg);
1448 tclass = TREE_CODE_CLASS (code);
1450 val = iterative_hash_object (code, val);
1457 case IDENTIFIER_NODE:
1458 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1462 int i, len = TREE_VEC_LENGTH (arg);
1463 for (i = 0; i < len; ++i)
1464 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1468 case TYPE_PACK_EXPANSION:
1469 case EXPR_PACK_EXPANSION:
1470 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1472 case ARGUMENT_PACK_SELECT:
1473 /* We can get one of these when re-hashing a previous entry in the middle
1474 of substituting into a pack expansion. Just look through it... */
1475 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1476 /* ...and fall through. */
1477 case TYPE_ARGUMENT_PACK:
1478 case NONTYPE_ARGUMENT_PACK:
1479 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1482 for (; arg; arg = TREE_CHAIN (arg))
1483 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1487 for (; arg; arg = OVL_CHAIN (arg))
1488 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1494 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1496 val = iterative_hash_template_arg (field, val);
1497 val = iterative_hash_template_arg (value, val);
1503 if (!DECL_ARTIFICIAL (arg))
1504 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1505 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1508 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1511 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1512 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1514 case TEMPLATE_PARM_INDEX:
1515 val = iterative_hash_template_arg
1516 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1517 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1518 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1521 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1522 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1523 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1526 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1528 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1532 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1533 code = TREE_CODE (TREE_OPERAND (arg, 1));
1534 val = iterative_hash_object (code, val);
1535 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1541 if (TYPE_CANONICAL (arg))
1542 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1544 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1545 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1546 /* Otherwise just compare the types during lookup. */
1549 case tcc_declaration:
1551 return iterative_hash_expr (arg, val);
1554 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1556 unsigned n = TREE_OPERAND_LENGTH (arg);
1557 for (i = 0; i < n; ++i)
1558 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1567 /* Unregister the specialization SPEC as a specialization of TMPL.
1568 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1569 if the SPEC was listed as a specialization of TMPL.
1571 Note that SPEC has been ggc_freed, so we can't look inside it. */
1574 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1579 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1580 elt.args = TI_ARGS (tinfo);
1581 elt.spec = NULL_TREE;
1583 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1586 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1587 gcc_assert (new_spec != NULL_TREE);
1588 (*slot)->spec = new_spec;
1595 /* Compare an entry in the local specializations hash table P1 (which
1596 is really a pointer to a TREE_LIST) with P2 (which is really a
1600 eq_local_specializations (const void *p1, const void *p2)
1602 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1605 /* Hash P1, an entry in the local specializations table. */
1608 hash_local_specialization (const void* p1)
1610 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1613 /* Like register_specialization, but for local declarations. We are
1614 registering SPEC, an instantiation of TMPL. */
1617 register_local_specialization (tree spec, tree tmpl)
1621 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1622 htab_hash_pointer (tmpl), INSERT);
1623 *slot = build_tree_list (spec, tmpl);
1626 /* TYPE is a class type. Returns true if TYPE is an explicitly
1627 specialized class. */
1630 explicit_class_specialization_p (tree type)
1632 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1634 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1637 /* Print the list of candidate FNS in an error message. */
1640 print_candidates (tree fns)
1645 const char *str = "candidates are:";
1647 if (is_overloaded_fn (fns))
1649 for (f = fns; f; f = OVL_NEXT (f))
1651 error ("%s %+#D", str, OVL_CURRENT (f));
1655 else for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1657 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1658 error ("%s %+#D", str, OVL_CURRENT (f));
1663 /* Returns the template (one of the functions given by TEMPLATE_ID)
1664 which can be specialized to match the indicated DECL with the
1665 explicit template args given in TEMPLATE_ID. The DECL may be
1666 NULL_TREE if none is available. In that case, the functions in
1667 TEMPLATE_ID are non-members.
1669 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1670 specialization of a member template.
1672 The TEMPLATE_COUNT is the number of references to qualifying
1673 template classes that appeared in the name of the function. See
1674 check_explicit_specialization for a more accurate description.
1676 TSK indicates what kind of template declaration (if any) is being
1677 declared. TSK_TEMPLATE indicates that the declaration given by
1678 DECL, though a FUNCTION_DECL, has template parameters, and is
1679 therefore a template function.
1681 The template args (those explicitly specified and those deduced)
1682 are output in a newly created vector *TARGS_OUT.
1684 If it is impossible to determine the result, an error message is
1685 issued. The error_mark_node is returned to indicate failure. */
1688 determine_specialization (tree template_id,
1691 int need_member_template,
1697 tree explicit_targs;
1698 tree candidates = NULL_TREE;
1699 /* A TREE_LIST of templates of which DECL may be a specialization.
1700 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1701 corresponding TREE_PURPOSE is the set of template arguments that,
1702 when used to instantiate the template, would produce a function
1703 with the signature of DECL. */
1704 tree templates = NULL_TREE;
1706 struct cp_binding_level *b;
1708 *targs_out = NULL_TREE;
1710 if (template_id == error_mark_node || decl == error_mark_node)
1711 return error_mark_node;
1713 fns = TREE_OPERAND (template_id, 0);
1714 explicit_targs = TREE_OPERAND (template_id, 1);
1716 if (fns == error_mark_node)
1717 return error_mark_node;
1719 /* Check for baselinks. */
1720 if (BASELINK_P (fns))
1721 fns = BASELINK_FUNCTIONS (fns);
1723 if (!is_overloaded_fn (fns))
1725 error ("%qD is not a function template", fns);
1726 return error_mark_node;
1729 /* Count the number of template headers specified for this
1732 for (b = current_binding_level;
1733 b->kind == sk_template_parms;
1737 for (; fns; fns = OVL_NEXT (fns))
1739 tree fn = OVL_CURRENT (fns);
1741 if (TREE_CODE (fn) == TEMPLATE_DECL)
1743 tree decl_arg_types;
1746 /* In case of explicit specialization, we need to check if
1747 the number of template headers appearing in the specialization
1748 is correct. This is usually done in check_explicit_specialization,
1749 but the check done there cannot be exhaustive when specializing
1750 member functions. Consider the following code:
1752 template <> void A<int>::f(int);
1753 template <> template <> void A<int>::f(int);
1755 Assuming that A<int> is not itself an explicit specialization
1756 already, the first line specializes "f" which is a non-template
1757 member function, whilst the second line specializes "f" which
1758 is a template member function. So both lines are syntactically
1759 correct, and check_explicit_specialization does not reject
1762 Here, we can do better, as we are matching the specialization
1763 against the declarations. We count the number of template
1764 headers, and we check if they match TEMPLATE_COUNT + 1
1765 (TEMPLATE_COUNT is the number of qualifying template classes,
1766 plus there must be another header for the member template
1769 Notice that if header_count is zero, this is not a
1770 specialization but rather a template instantiation, so there
1771 is no check we can perform here. */
1772 if (header_count && header_count != template_count + 1)
1775 /* Check that the number of template arguments at the
1776 innermost level for DECL is the same as for FN. */
1777 if (current_binding_level->kind == sk_template_parms
1778 && !current_binding_level->explicit_spec_p
1779 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1780 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1781 (current_template_parms))))
1784 /* DECL might be a specialization of FN. */
1785 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1786 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1788 /* For a non-static member function, we need to make sure
1789 that the const qualification is the same. Since
1790 get_bindings does not try to merge the "this" parameter,
1791 we must do the comparison explicitly. */
1792 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1793 && !same_type_p (TREE_VALUE (fn_arg_types),
1794 TREE_VALUE (decl_arg_types)))
1797 /* Skip the "this" parameter and, for constructors of
1798 classes with virtual bases, the VTT parameter. A
1799 full specialization of a constructor will have a VTT
1800 parameter, but a template never will. */
1802 = skip_artificial_parms_for (decl, decl_arg_types);
1804 = skip_artificial_parms_for (fn, fn_arg_types);
1806 /* Check that the number of function parameters matches.
1808 template <class T> void f(int i = 0);
1809 template <> void f<int>();
1810 The specialization f<int> is invalid but is not caught
1811 by get_bindings below. */
1812 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1815 /* Function templates cannot be specializations; there are
1816 no partial specializations of functions. Therefore, if
1817 the type of DECL does not match FN, there is no
1819 if (tsk == tsk_template)
1821 if (compparms (fn_arg_types, decl_arg_types))
1822 candidates = tree_cons (NULL_TREE, fn, candidates);
1826 /* See whether this function might be a specialization of this
1828 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1831 /* We cannot deduce template arguments that when used to
1832 specialize TMPL will produce DECL. */
1835 /* Save this template, and the arguments deduced. */
1836 templates = tree_cons (targs, fn, templates);
1838 else if (need_member_template)
1839 /* FN is an ordinary member function, and we need a
1840 specialization of a member template. */
1842 else if (TREE_CODE (fn) != FUNCTION_DECL)
1843 /* We can get IDENTIFIER_NODEs here in certain erroneous
1846 else if (!DECL_FUNCTION_MEMBER_P (fn))
1847 /* This is just an ordinary non-member function. Nothing can
1848 be a specialization of that. */
1850 else if (DECL_ARTIFICIAL (fn))
1851 /* Cannot specialize functions that are created implicitly. */
1855 tree decl_arg_types;
1857 /* This is an ordinary member function. However, since
1858 we're here, we can assume it's enclosing class is a
1859 template class. For example,
1861 template <typename T> struct S { void f(); };
1862 template <> void S<int>::f() {}
1864 Here, S<int>::f is a non-template, but S<int> is a
1865 template class. If FN has the same type as DECL, we
1866 might be in business. */
1868 if (!DECL_TEMPLATE_INFO (fn))
1869 /* Its enclosing class is an explicit specialization
1870 of a template class. This is not a candidate. */
1873 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1874 TREE_TYPE (TREE_TYPE (fn))))
1875 /* The return types differ. */
1878 /* Adjust the type of DECL in case FN is a static member. */
1879 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1880 if (DECL_STATIC_FUNCTION_P (fn)
1881 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1882 decl_arg_types = TREE_CHAIN (decl_arg_types);
1884 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1887 candidates = tree_cons (NULL_TREE, fn, candidates);
1891 if (templates && TREE_CHAIN (templates))
1897 It is possible for a specialization with a given function
1898 signature to be instantiated from more than one function
1899 template. In such cases, explicit specification of the
1900 template arguments must be used to uniquely identify the
1901 function template specialization being specialized.
1903 Note that here, there's no suggestion that we're supposed to
1904 determine which of the candidate templates is most
1905 specialized. However, we, also have:
1909 Partial ordering of overloaded function template
1910 declarations is used in the following contexts to select
1911 the function template to which a function template
1912 specialization refers:
1914 -- when an explicit specialization refers to a function
1917 So, we do use the partial ordering rules, at least for now.
1918 This extension can only serve to make invalid programs valid,
1919 so it's safe. And, there is strong anecdotal evidence that
1920 the committee intended the partial ordering rules to apply;
1921 the EDG front end has that behavior, and John Spicer claims
1922 that the committee simply forgot to delete the wording in
1923 [temp.expl.spec]. */
1924 tree tmpl = most_specialized_instantiation (templates);
1925 if (tmpl != error_mark_node)
1928 TREE_CHAIN (templates) = NULL_TREE;
1932 if (templates == NULL_TREE && candidates == NULL_TREE)
1934 error ("template-id %qD for %q+D does not match any template "
1935 "declaration", template_id, decl);
1936 return error_mark_node;
1938 else if ((templates && TREE_CHAIN (templates))
1939 || (candidates && TREE_CHAIN (candidates))
1940 || (templates && candidates))
1942 error ("ambiguous template specialization %qD for %q+D",
1944 candidates = chainon (candidates, templates);
1945 print_candidates (candidates);
1946 return error_mark_node;
1949 /* We have one, and exactly one, match. */
1952 tree fn = TREE_VALUE (candidates);
1953 *targs_out = copy_node (DECL_TI_ARGS (fn));
1954 /* DECL is a re-declaration or partial instantiation of a template
1956 if (TREE_CODE (fn) == TEMPLATE_DECL)
1958 /* It was a specialization of an ordinary member function in a
1960 return DECL_TI_TEMPLATE (fn);
1963 /* It was a specialization of a template. */
1964 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1965 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1967 *targs_out = copy_node (targs);
1968 SET_TMPL_ARGS_LEVEL (*targs_out,
1969 TMPL_ARGS_DEPTH (*targs_out),
1970 TREE_PURPOSE (templates));
1973 *targs_out = TREE_PURPOSE (templates);
1974 return TREE_VALUE (templates);
1977 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1978 but with the default argument values filled in from those in the
1982 copy_default_args_to_explicit_spec_1 (tree spec_types,
1985 tree new_spec_types;
1990 if (spec_types == void_list_node)
1991 return void_list_node;
1993 /* Substitute into the rest of the list. */
1995 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1996 TREE_CHAIN (tmpl_types));
1998 /* Add the default argument for this parameter. */
1999 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2000 TREE_VALUE (spec_types),
2004 /* DECL is an explicit specialization. Replicate default arguments
2005 from the template it specializes. (That way, code like:
2007 template <class T> void f(T = 3);
2008 template <> void f(double);
2011 works, as required.) An alternative approach would be to look up
2012 the correct default arguments at the call-site, but this approach
2013 is consistent with how implicit instantiations are handled. */
2016 copy_default_args_to_explicit_spec (tree decl)
2021 tree new_spec_types;
2025 tree object_type = NULL_TREE;
2026 tree in_charge = NULL_TREE;
2027 tree vtt = NULL_TREE;
2029 /* See if there's anything we need to do. */
2030 tmpl = DECL_TI_TEMPLATE (decl);
2031 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2032 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2033 if (TREE_PURPOSE (t))
2038 old_type = TREE_TYPE (decl);
2039 spec_types = TYPE_ARG_TYPES (old_type);
2041 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2043 /* Remove the this pointer, but remember the object's type for
2045 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2046 spec_types = TREE_CHAIN (spec_types);
2047 tmpl_types = TREE_CHAIN (tmpl_types);
2049 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2051 /* DECL may contain more parameters than TMPL due to the extra
2052 in-charge parameter in constructors and destructors. */
2053 in_charge = spec_types;
2054 spec_types = TREE_CHAIN (spec_types);
2056 if (DECL_HAS_VTT_PARM_P (decl))
2059 spec_types = TREE_CHAIN (spec_types);
2063 /* Compute the merged default arguments. */
2065 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2067 /* Compute the new FUNCTION_TYPE. */
2071 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2076 /* Put the in-charge parameter back. */
2077 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2078 TREE_VALUE (in_charge),
2081 new_type = build_method_type_directly (object_type,
2082 TREE_TYPE (old_type),
2086 new_type = build_function_type (TREE_TYPE (old_type),
2088 new_type = cp_build_type_attribute_variant (new_type,
2089 TYPE_ATTRIBUTES (old_type));
2090 new_type = build_exception_variant (new_type,
2091 TYPE_RAISES_EXCEPTIONS (old_type));
2092 TREE_TYPE (decl) = new_type;
2095 /* Check to see if the function just declared, as indicated in
2096 DECLARATOR, and in DECL, is a specialization of a function
2097 template. We may also discover that the declaration is an explicit
2098 instantiation at this point.
2100 Returns DECL, or an equivalent declaration that should be used
2101 instead if all goes well. Issues an error message if something is
2102 amiss. Returns error_mark_node if the error is not easily
2105 FLAGS is a bitmask consisting of the following flags:
2107 2: The function has a definition.
2108 4: The function is a friend.
2110 The TEMPLATE_COUNT is the number of references to qualifying
2111 template classes that appeared in the name of the function. For
2114 template <class T> struct S { void f(); };
2117 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2118 classes are not counted in the TEMPLATE_COUNT, so that in
2120 template <class T> struct S {};
2121 template <> struct S<int> { void f(); }
2122 template <> void S<int>::f();
2124 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2125 invalid; there should be no template <>.)
2127 If the function is a specialization, it is marked as such via
2128 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2129 is set up correctly, and it is added to the list of specializations
2130 for that template. */
2133 check_explicit_specialization (tree declarator,
2138 int have_def = flags & 2;
2139 int is_friend = flags & 4;
2140 int specialization = 0;
2141 int explicit_instantiation = 0;
2142 int member_specialization = 0;
2143 tree ctype = DECL_CLASS_CONTEXT (decl);
2144 tree dname = DECL_NAME (decl);
2149 if (!processing_specialization)
2152 tsk = tsk_excessive_parms;
2155 tsk = current_tmpl_spec_kind (template_count);
2160 if (processing_specialization)
2163 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2165 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2168 /* This could be something like:
2170 template <class T> void f(T);
2171 class S { friend void f<>(int); } */
2175 /* This case handles bogus declarations like template <>
2176 template <class T> void f<int>(); */
2178 error ("template-id %qD in declaration of primary template",
2185 case tsk_invalid_member_spec:
2186 /* The error has already been reported in
2187 check_specialization_scope. */
2188 return error_mark_node;
2190 case tsk_invalid_expl_inst:
2191 error ("template parameter list used in explicit instantiation");
2197 error ("definition provided for explicit instantiation");
2199 explicit_instantiation = 1;
2202 case tsk_excessive_parms:
2203 case tsk_insufficient_parms:
2204 if (tsk == tsk_excessive_parms)
2205 error ("too many template parameter lists in declaration of %qD",
2207 else if (template_header_count)
2208 error("too few template parameter lists in declaration of %qD", decl);
2210 error("explicit specialization of %qD must be introduced by "
2211 "%<template <>%>", decl);
2215 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2217 member_specialization = 1;
2223 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2225 /* This case handles bogus declarations like template <>
2226 template <class T> void f<int>(); */
2228 if (uses_template_parms (declarator))
2229 error ("function template partial specialization %qD "
2230 "is not allowed", declarator);
2232 error ("template-id %qD in declaration of primary template",
2237 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2238 /* This is a specialization of a member template, without
2239 specialization the containing class. Something like:
2241 template <class T> struct S {
2242 template <class U> void f (U);
2244 template <> template <class U> void S<int>::f(U) {}
2246 That's a specialization -- but of the entire template. */
2254 if (specialization || member_specialization)
2256 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2257 for (; t; t = TREE_CHAIN (t))
2258 if (TREE_PURPOSE (t))
2260 permerror (input_location,
2261 "default argument specified in explicit specialization");
2266 if (specialization || member_specialization || explicit_instantiation)
2268 tree tmpl = NULL_TREE;
2269 tree targs = NULL_TREE;
2271 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2272 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2276 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2281 /* If there is no class context, the explicit instantiation
2282 must be at namespace scope. */
2283 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2285 /* Find the namespace binding, using the declaration
2287 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2289 if (fns == error_mark_node || !is_overloaded_fn (fns))
2291 error ("%qD is not a template function", dname);
2292 fns = error_mark_node;
2296 tree fn = OVL_CURRENT (fns);
2297 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2298 CP_DECL_CONTEXT (fn)))
2299 error ("%qD is not declared in %qD",
2300 decl, current_namespace);
2304 declarator = lookup_template_function (fns, NULL_TREE);
2307 if (declarator == error_mark_node)
2308 return error_mark_node;
2310 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2312 if (!explicit_instantiation)
2313 /* A specialization in class scope. This is invalid,
2314 but the error will already have been flagged by
2315 check_specialization_scope. */
2316 return error_mark_node;
2319 /* It's not valid to write an explicit instantiation in
2322 class C { template void f(); }
2324 This case is caught by the parser. However, on
2327 template class C { void f(); };
2329 (which is invalid) we can get here. The error will be
2336 else if (ctype != NULL_TREE
2337 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2340 /* Find the list of functions in ctype that have the same
2341 name as the declared function. */
2342 tree name = TREE_OPERAND (declarator, 0);
2343 tree fns = NULL_TREE;
2346 if (constructor_name_p (name, ctype))
2348 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2350 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2351 : !CLASSTYPE_DESTRUCTORS (ctype))
2353 /* From [temp.expl.spec]:
2355 If such an explicit specialization for the member
2356 of a class template names an implicitly-declared
2357 special member function (clause _special_), the
2358 program is ill-formed.
2360 Similar language is found in [temp.explicit]. */
2361 error ("specialization of implicitly-declared special member function");
2362 return error_mark_node;
2365 name = is_constructor ? ctor_identifier : dtor_identifier;
2368 if (!DECL_CONV_FN_P (decl))
2370 idx = lookup_fnfields_1 (ctype, name);
2372 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2376 VEC(tree,gc) *methods;
2379 /* For a type-conversion operator, we cannot do a
2380 name-based lookup. We might be looking for `operator
2381 int' which will be a specialization of `operator T'.
2382 So, we find *all* the conversion operators, and then
2383 select from them. */
2386 methods = CLASSTYPE_METHOD_VEC (ctype);
2388 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2389 VEC_iterate (tree, methods, idx, ovl);
2392 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2393 /* There are no more conversion functions. */
2396 /* Glue all these conversion functions together
2397 with those we already have. */
2398 for (; ovl; ovl = OVL_NEXT (ovl))
2399 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2403 if (fns == NULL_TREE)
2405 error ("no member function %qD declared in %qT", name, ctype);
2406 return error_mark_node;
2409 TREE_OPERAND (declarator, 0) = fns;
2412 /* Figure out what exactly is being specialized at this point.
2413 Note that for an explicit instantiation, even one for a
2414 member function, we cannot tell apriori whether the
2415 instantiation is for a member template, or just a member
2416 function of a template class. Even if a member template is
2417 being instantiated, the member template arguments may be
2418 elided if they can be deduced from the rest of the
2420 tmpl = determine_specialization (declarator, decl,
2422 member_specialization,
2426 if (!tmpl || tmpl == error_mark_node)
2427 /* We couldn't figure out what this declaration was
2429 return error_mark_node;
2432 tree gen_tmpl = most_general_template (tmpl);
2434 if (explicit_instantiation)
2436 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2437 is done by do_decl_instantiation later. */
2439 int arg_depth = TMPL_ARGS_DEPTH (targs);
2440 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2442 if (arg_depth > parm_depth)
2444 /* If TMPL is not the most general template (for
2445 example, if TMPL is a friend template that is
2446 injected into namespace scope), then there will
2447 be too many levels of TARGS. Remove some of them
2452 new_targs = make_tree_vec (parm_depth);
2453 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2454 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2455 = TREE_VEC_ELT (targs, i);
2459 return instantiate_template (tmpl, targs, tf_error);
2462 /* If we thought that the DECL was a member function, but it
2463 turns out to be specializing a static member function,
2464 make DECL a static member function as well. */
2465 if (DECL_STATIC_FUNCTION_P (tmpl)
2466 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2467 revert_static_member_fn (decl);
2469 /* If this is a specialization of a member template of a
2470 template class, we want to return the TEMPLATE_DECL, not
2471 the specialization of it. */
2472 if (tsk == tsk_template)
2474 tree result = DECL_TEMPLATE_RESULT (tmpl);
2475 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2476 DECL_INITIAL (result) = NULL_TREE;
2480 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2481 DECL_SOURCE_LOCATION (result)
2482 = DECL_SOURCE_LOCATION (decl);
2483 /* We want to use the argument list specified in the
2484 definition, not in the original declaration. */
2485 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2486 for (parm = DECL_ARGUMENTS (result); parm;
2487 parm = TREE_CHAIN (parm))
2488 DECL_CONTEXT (parm) = result;
2490 return register_specialization (tmpl, gen_tmpl, targs,
2494 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2495 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2497 /* Inherit default function arguments from the template
2498 DECL is specializing. */
2499 copy_default_args_to_explicit_spec (decl);
2501 /* This specialization has the same protection as the
2502 template it specializes. */
2503 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2504 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2506 /* 7.1.1-1 [dcl.stc]
2508 A storage-class-specifier shall not be specified in an
2509 explicit specialization...
2511 The parser rejects these, so unless action is taken here,
2512 explicit function specializations will always appear with
2515 The action recommended by the C++ CWG in response to C++
2516 defect report 605 is to make the storage class and linkage
2517 of the explicit specialization match the templated function:
2519 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2521 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2523 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2524 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2526 /* This specialization has the same linkage and visibility as
2527 the function template it specializes. */
2528 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2529 if (! TREE_PUBLIC (decl))
2531 DECL_INTERFACE_KNOWN (decl) = 1;
2532 DECL_NOT_REALLY_EXTERN (decl) = 1;
2534 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2535 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2537 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2538 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2542 /* If DECL is a friend declaration, declared using an
2543 unqualified name, the namespace associated with DECL may
2544 have been set incorrectly. For example, in:
2546 template <typename T> void f(T);
2548 struct S { friend void f<int>(int); }
2551 we will have set the DECL_CONTEXT for the friend
2552 declaration to N, rather than to the global namespace. */
2553 if (DECL_NAMESPACE_SCOPE_P (decl))
2554 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2556 if (is_friend && !have_def)
2557 /* This is not really a declaration of a specialization.
2558 It's just the name of an instantiation. But, it's not
2559 a request for an instantiation, either. */
2560 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2561 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2562 /* This is indeed a specialization. In case of constructors
2563 and destructors, we need in-charge and not-in-charge
2564 versions in V3 ABI. */
2565 clone_function_decl (decl, /*update_method_vec_p=*/0);
2567 /* Register this specialization so that we can find it
2569 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2576 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2577 parameters. These are represented in the same format used for
2578 DECL_TEMPLATE_PARMS. */
2581 comp_template_parms (const_tree parms1, const_tree parms2)
2586 if (parms1 == parms2)
2589 for (p1 = parms1, p2 = parms2;
2590 p1 != NULL_TREE && p2 != NULL_TREE;
2591 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2593 tree t1 = TREE_VALUE (p1);
2594 tree t2 = TREE_VALUE (p2);
2597 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2598 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2600 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2603 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2605 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2606 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2608 /* If either of the template parameters are invalid, assume
2609 they match for the sake of error recovery. */
2610 if (parm1 == error_mark_node || parm2 == error_mark_node)
2613 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2616 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2617 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2618 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2620 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2625 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2626 /* One set of parameters has more parameters lists than the
2633 /* Determine whether PARM is a parameter pack. */
2636 template_parameter_pack_p (const_tree parm)
2638 /* Determine if we have a non-type template parameter pack. */
2639 if (TREE_CODE (parm) == PARM_DECL)
2640 return (DECL_TEMPLATE_PARM_P (parm)
2641 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2643 /* If this is a list of template parameters, we could get a
2644 TYPE_DECL or a TEMPLATE_DECL. */
2645 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2646 parm = TREE_TYPE (parm);
2648 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2649 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2650 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2653 /* Determine if T is a function parameter pack. */
2656 function_parameter_pack_p (const_tree t)
2658 if (t && TREE_CODE (t) == PARM_DECL)
2659 return FUNCTION_PARAMETER_PACK_P (t);
2663 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2664 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2667 get_function_template_decl (const_tree primary_func_tmpl_inst)
2669 if (! primary_func_tmpl_inst
2670 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2671 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2674 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2677 /* Return true iff the function parameter PARAM_DECL was expanded
2678 from the function parameter pack PACK. */
2681 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2683 if (DECL_ARTIFICIAL (param_decl)
2684 || !function_parameter_pack_p (pack))
2687 gcc_assert (DECL_NAME (param_decl) && DECL_NAME (pack));
2689 /* The parameter pack and its pack arguments have the same
2691 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2694 /* Determine whether ARGS describes a variadic template args list,
2695 i.e., one that is terminated by a template argument pack. */
2698 template_args_variadic_p (tree args)
2703 if (args == NULL_TREE)
2706 args = INNERMOST_TEMPLATE_ARGS (args);
2707 nargs = TREE_VEC_LENGTH (args);
2712 last_parm = TREE_VEC_ELT (args, nargs - 1);
2714 return ARGUMENT_PACK_P (last_parm);
2717 /* Generate a new name for the parameter pack name NAME (an
2718 IDENTIFIER_NODE) that incorporates its */
2721 make_ith_pack_parameter_name (tree name, int i)
2723 /* Munge the name to include the parameter index. */
2724 #define NUMBUF_LEN 128
2725 char numbuf[NUMBUF_LEN];
2729 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2730 newname_len = IDENTIFIER_LENGTH (name)
2731 + strlen (numbuf) + 2;
2732 newname = (char*)alloca (newname_len);
2733 snprintf (newname, newname_len,
2734 "%s#%i", IDENTIFIER_POINTER (name), i);
2735 return get_identifier (newname);
2738 /* Return true if T is a primary function
2739 or class template instantiation. */
2742 primary_template_instantiation_p (const_tree t)
2747 if (TREE_CODE (t) == FUNCTION_DECL)
2748 return DECL_LANG_SPECIFIC (t)
2749 && DECL_TEMPLATE_INSTANTIATION (t)
2750 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2751 else if (CLASS_TYPE_P (t))
2752 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2753 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2757 /* Return true if PARM is a template template parameter. */
2760 template_template_parameter_p (const_tree parm)
2762 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2765 /* Return the template parameters of T if T is a
2766 primary template instantiation, NULL otherwise. */
2769 get_primary_template_innermost_parameters (const_tree t)
2771 tree parms = NULL, template_info = NULL;
2773 if ((template_info = get_template_info (t))
2774 && primary_template_instantiation_p (t))
2775 parms = INNERMOST_TEMPLATE_PARMS
2776 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2781 /* Returns the template arguments of T if T is a template instantiation,
2785 get_template_innermost_arguments (const_tree t)
2787 tree args = NULL, template_info = NULL;
2789 if ((template_info = get_template_info (t))
2790 && TI_ARGS (template_info))
2791 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2796 /* Return the argument pack elements of T if T is a template argument pack,
2800 get_template_argument_pack_elems (const_tree t)
2802 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2803 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2806 return ARGUMENT_PACK_ARGS (t);
2809 /* Structure used to track the progress of find_parameter_packs_r. */
2810 struct find_parameter_pack_data
2812 /* TREE_LIST that will contain all of the parameter packs found by
2814 tree* parameter_packs;
2816 /* Set of AST nodes that have been visited by the traversal. */
2817 struct pointer_set_t *visited;
2820 /* Identifies all of the argument packs that occur in a template
2821 argument and appends them to the TREE_LIST inside DATA, which is a
2822 find_parameter_pack_data structure. This is a subroutine of
2823 make_pack_expansion and uses_parameter_packs. */
2825 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2828 struct find_parameter_pack_data* ppd =
2829 (struct find_parameter_pack_data*)data;
2830 bool parameter_pack_p = false;
2832 /* Identify whether this is a parameter pack or not. */
2833 switch (TREE_CODE (t))
2835 case TEMPLATE_PARM_INDEX:
2836 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2837 parameter_pack_p = true;
2840 case TEMPLATE_TYPE_PARM:
2841 case TEMPLATE_TEMPLATE_PARM:
2842 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2843 parameter_pack_p = true;
2847 if (FUNCTION_PARAMETER_PACK_P (t))
2849 /* We don't want to walk into the type of a PARM_DECL,
2850 because we don't want to see the type parameter pack. */
2852 parameter_pack_p = true;
2857 /* Not a parameter pack. */
2861 if (parameter_pack_p)
2863 /* Add this parameter pack to the list. */
2864 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2868 cp_walk_tree (&TYPE_CONTEXT (t),
2869 &find_parameter_packs_r, ppd, ppd->visited);
2871 /* This switch statement will return immediately if we don't find a
2873 switch (TREE_CODE (t))
2875 case TEMPLATE_PARM_INDEX:
2878 case BOUND_TEMPLATE_TEMPLATE_PARM:
2879 /* Check the template itself. */
2880 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2881 &find_parameter_packs_r, ppd, ppd->visited);
2882 /* Check the template arguments. */
2883 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2888 case TEMPLATE_TYPE_PARM:
2889 case TEMPLATE_TEMPLATE_PARM:
2896 if (TYPE_PTRMEMFUNC_P (t))
2902 if (TYPE_TEMPLATE_INFO (t))
2903 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2904 &find_parameter_packs_r, ppd, ppd->visited);
2910 cp_walk_tree (&TREE_TYPE (t),
2911 &find_parameter_packs_r, ppd, ppd->visited);
2915 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2920 case TYPE_PACK_EXPANSION:
2921 case EXPR_PACK_EXPANSION:
2926 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2931 case IDENTIFIER_NODE:
2932 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2944 /* Determines if the expression or type T uses any parameter packs. */
2946 uses_parameter_packs (tree t)
2948 tree parameter_packs = NULL_TREE;
2949 struct find_parameter_pack_data ppd;
2950 ppd.parameter_packs = ¶meter_packs;
2951 ppd.visited = pointer_set_create ();
2952 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2953 pointer_set_destroy (ppd.visited);
2954 return parameter_packs != NULL_TREE;
2957 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2958 representation a base-class initializer into a parameter pack
2959 expansion. If all goes well, the resulting node will be an
2960 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2963 make_pack_expansion (tree arg)
2966 tree parameter_packs = NULL_TREE;
2967 bool for_types = false;
2968 struct find_parameter_pack_data ppd;
2970 if (!arg || arg == error_mark_node)
2973 if (TREE_CODE (arg) == TREE_LIST)
2975 /* The only time we will see a TREE_LIST here is for a base
2976 class initializer. In this case, the TREE_PURPOSE will be a
2977 _TYPE node (representing the base class expansion we're
2978 initializing) and the TREE_VALUE will be a TREE_LIST
2979 containing the initialization arguments.
2981 The resulting expansion looks somewhat different from most
2982 expansions. Rather than returning just one _EXPANSION, we
2983 return a TREE_LIST whose TREE_PURPOSE is a
2984 TYPE_PACK_EXPANSION containing the bases that will be
2985 initialized. The TREE_VALUE will be identical to the
2986 original TREE_VALUE, which is a list of arguments that will
2987 be passed to each base. We do not introduce any new pack
2988 expansion nodes into the TREE_VALUE (although it is possible
2989 that some already exist), because the TREE_PURPOSE and
2990 TREE_VALUE all need to be expanded together with the same
2991 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2992 resulting TREE_PURPOSE will mention the parameter packs in
2993 both the bases and the arguments to the bases. */
2996 tree parameter_packs = NULL_TREE;
2998 /* Determine which parameter packs will be used by the base
3000 ppd.visited = pointer_set_create ();
3001 ppd.parameter_packs = ¶meter_packs;
3002 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3005 if (parameter_packs == NULL_TREE)
3007 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3008 pointer_set_destroy (ppd.visited);
3009 return error_mark_node;
3012 if (TREE_VALUE (arg) != void_type_node)
3014 /* Collect the sets of parameter packs used in each of the
3015 initialization arguments. */
3016 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3018 /* Determine which parameter packs will be expanded in this
3020 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3025 pointer_set_destroy (ppd.visited);
3027 /* Create the pack expansion type for the base type. */
3028 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3029 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3030 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3032 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3033 they will rarely be compared to anything. */
3034 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3036 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3039 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3042 /* Build the PACK_EXPANSION_* node. */
3044 ? cxx_make_type (TYPE_PACK_EXPANSION)
3045 : make_node (EXPR_PACK_EXPANSION);
3046 SET_PACK_EXPANSION_PATTERN (result, arg);
3047 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3049 /* Propagate type and const-expression information. */
3050 TREE_TYPE (result) = TREE_TYPE (arg);
3051 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3054 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3055 they will rarely be compared to anything. */
3056 SET_TYPE_STRUCTURAL_EQUALITY (result);
3058 /* Determine which parameter packs will be expanded. */
3059 ppd.parameter_packs = ¶meter_packs;
3060 ppd.visited = pointer_set_create ();
3061 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3062 pointer_set_destroy (ppd.visited);
3064 /* Make sure we found some parameter packs. */
3065 if (parameter_packs == NULL_TREE)
3068 error ("expansion pattern %<%T%> contains no argument packs", arg);
3070 error ("expansion pattern %<%E%> contains no argument packs", arg);
3071 return error_mark_node;
3073 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3078 /* Checks T for any "bare" parameter packs, which have not yet been
3079 expanded, and issues an error if any are found. This operation can
3080 only be done on full expressions or types (e.g., an expression
3081 statement, "if" condition, etc.), because we could have expressions like:
3083 foo(f(g(h(args)))...)
3085 where "args" is a parameter pack. check_for_bare_parameter_packs
3086 should not be called for the subexpressions args, h(args),
3087 g(h(args)), or f(g(h(args))), because we would produce erroneous
3090 Returns TRUE and emits an error if there were bare parameter packs,
3091 returns FALSE otherwise. */
3093 check_for_bare_parameter_packs (tree t)
3095 tree parameter_packs = NULL_TREE;
3096 struct find_parameter_pack_data ppd;
3098 if (!processing_template_decl || !t || t == error_mark_node)
3101 if (TREE_CODE (t) == TYPE_DECL)
3104 ppd.parameter_packs = ¶meter_packs;
3105 ppd.visited = pointer_set_create ();
3106 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3107 pointer_set_destroy (ppd.visited);
3109 if (parameter_packs)
3111 error ("parameter packs not expanded with %<...%>:");
3112 while (parameter_packs)
3114 tree pack = TREE_VALUE (parameter_packs);
3115 tree name = NULL_TREE;
3117 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3118 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3119 name = TYPE_NAME (pack);
3120 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3121 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3123 name = DECL_NAME (pack);
3126 inform (input_location, " %qD", name);
3128 inform (input_location, " <anonymous>");
3130 parameter_packs = TREE_CHAIN (parameter_packs);
3139 /* Expand any parameter packs that occur in the template arguments in
3142 expand_template_argument_pack (tree args)
3144 tree result_args = NULL_TREE;
3145 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3146 int num_result_args = -1;
3148 /* First, determine if we need to expand anything, and the number of
3149 slots we'll need. */
3150 for (in_arg = 0; in_arg < nargs; ++in_arg)
3152 tree arg = TREE_VEC_ELT (args, in_arg);
3153 if (arg == NULL_TREE)
3155 if (ARGUMENT_PACK_P (arg))
3157 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3158 if (num_result_args < 0)
3159 num_result_args = in_arg + num_packed;
3161 num_result_args += num_packed;
3165 if (num_result_args >= 0)
3170 /* If no expansion is necessary, we're done. */
3171 if (num_result_args < 0)
3174 /* Expand arguments. */
3175 result_args = make_tree_vec (num_result_args);
3176 for (in_arg = 0; in_arg < nargs; ++in_arg)
3178 tree arg = TREE_VEC_ELT (args, in_arg);
3179 if (ARGUMENT_PACK_P (arg))
3181 tree packed = ARGUMENT_PACK_ARGS (arg);
3182 int i, num_packed = TREE_VEC_LENGTH (packed);
3183 for (i = 0; i < num_packed; ++i, ++out_arg)
3184 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3188 TREE_VEC_ELT (result_args, out_arg) = arg;
3196 /* Checks if DECL shadows a template parameter.
3198 [temp.local]: A template-parameter shall not be redeclared within its
3199 scope (including nested scopes).
3201 Emits an error and returns TRUE if the DECL shadows a parameter,
3202 returns FALSE otherwise. */
3205 check_template_shadow (tree decl)
3209 /* If we're not in a template, we can't possibly shadow a template
3211 if (!current_template_parms)
3214 /* Figure out what we're shadowing. */
3215 if (TREE_CODE (decl) == OVERLOAD)
3216 decl = OVL_CURRENT (decl);
3217 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3219 /* If there's no previous binding for this name, we're not shadowing
3220 anything, let alone a template parameter. */
3224 /* If we're not shadowing a template parameter, we're done. Note
3225 that OLDDECL might be an OVERLOAD (or perhaps even an
3226 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3228 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3231 /* We check for decl != olddecl to avoid bogus errors for using a
3232 name inside a class. We check TPFI to avoid duplicate errors for
3233 inline member templates. */
3235 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3238 error ("declaration of %q+#D", decl);
3239 error (" shadows template parm %q+#D", olddecl);
3243 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3244 ORIG_LEVEL, DECL, and TYPE. */
3247 build_template_parm_index (int index,
3253 tree t = make_node (TEMPLATE_PARM_INDEX);
3254 TEMPLATE_PARM_IDX (t) = index;
3255 TEMPLATE_PARM_LEVEL (t) = level;
3256 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3257 TEMPLATE_PARM_DECL (t) = decl;
3258 TREE_TYPE (t) = type;
3259 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3260 TREE_READONLY (t) = TREE_READONLY (decl);
3265 /* Find the canonical type parameter for the given template type
3266 parameter. Returns the canonical type parameter, which may be TYPE
3267 if no such parameter existed. */
3269 canonical_type_parameter (tree type)
3272 int idx = TEMPLATE_TYPE_IDX (type);
3273 if (!canonical_template_parms)
3274 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3276 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3277 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3279 list = VEC_index (tree, canonical_template_parms, idx);
3280 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3281 list = TREE_CHAIN (list);
3284 return TREE_VALUE (list);
3287 VEC_replace(tree, canonical_template_parms, idx,
3288 tree_cons (NULL_TREE, type,
3289 VEC_index (tree, canonical_template_parms, idx)));
3294 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3295 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3296 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3297 new one is created. */
3300 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3301 tsubst_flags_t complain)
3303 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3304 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3305 != TEMPLATE_PARM_LEVEL (index) - levels))
3307 tree orig_decl = TEMPLATE_PARM_DECL (index);
3310 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3311 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3312 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3313 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3314 DECL_ARTIFICIAL (decl) = 1;
3315 SET_DECL_TEMPLATE_PARM_P (decl);
3317 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3318 TEMPLATE_PARM_LEVEL (index) - levels,
3319 TEMPLATE_PARM_ORIG_LEVEL (index),
3321 TEMPLATE_PARM_DESCENDANTS (index) = t;
3322 TEMPLATE_PARM_PARAMETER_PACK (t)
3323 = TEMPLATE_PARM_PARAMETER_PACK (index);
3325 /* Template template parameters need this. */
3326 if (TREE_CODE (decl) == TEMPLATE_DECL)
3327 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3328 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3332 return TEMPLATE_PARM_DESCENDANTS (index);
3335 /* Process information from new template parameter PARM and append it to the
3336 LIST being built. This new parameter is a non-type parameter iff
3337 IS_NON_TYPE is true. This new parameter is a parameter
3338 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3342 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3343 bool is_parameter_pack)
3350 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3351 defval = TREE_PURPOSE (parm);
3355 tree p = tree_last (list);
3357 if (p && TREE_VALUE (p) != error_mark_node)
3360 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3361 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3363 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3373 parm = TREE_VALUE (parm);
3375 SET_DECL_TEMPLATE_PARM_P (parm);
3377 if (TREE_TYPE (parm) == error_mark_node)
3379 err_parm_list = build_tree_list (defval, parm);
3380 TREE_VALUE (err_parm_list) = error_mark_node;
3381 return chainon (list, err_parm_list);
3387 The top-level cv-qualifiers on the template-parameter are
3388 ignored when determining its type. */
3389 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3390 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3392 err_parm_list = build_tree_list (defval, parm);
3393 TREE_VALUE (err_parm_list) = error_mark_node;
3394 return chainon (list, err_parm_list);
3397 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3399 /* This template parameter is not a parameter pack, but it
3400 should be. Complain about "bare" parameter packs. */
3401 check_for_bare_parameter_packs (TREE_TYPE (parm));
3403 /* Recover by calling this a parameter pack. */
3404 is_parameter_pack = true;
3408 /* A template parameter is not modifiable. */
3409 TREE_CONSTANT (parm) = 1;
3410 TREE_READONLY (parm) = 1;
3411 decl = build_decl (parm_loc,
3412 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3413 TREE_CONSTANT (decl) = 1;
3414 TREE_READONLY (decl) = 1;
3415 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3416 = build_template_parm_index (idx, processing_template_decl,
3417 processing_template_decl,
3418 decl, TREE_TYPE (parm));
3420 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3421 = is_parameter_pack;
3426 parm = TREE_VALUE (TREE_VALUE (parm));
3428 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3430 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3431 /* This is for distinguishing between real templates and template
3432 template parameters */
3433 TREE_TYPE (parm) = t;
3434 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3439 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3440 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3441 decl = build_decl (parm_loc,
3442 TYPE_DECL, parm, t);
3445 TYPE_NAME (t) = decl;
3446 TYPE_STUB_DECL (t) = decl;
3448 TEMPLATE_TYPE_PARM_INDEX (t)
3449 = build_template_parm_index (idx, processing_template_decl,
3450 processing_template_decl,
3451 decl, TREE_TYPE (parm));
3452 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3453 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3455 DECL_ARTIFICIAL (decl) = 1;
3456 SET_DECL_TEMPLATE_PARM_P (decl);
3458 parm = build_tree_list (defval, parm);
3459 return chainon (list, parm);
3462 /* The end of a template parameter list has been reached. Process the
3463 tree list into a parameter vector, converting each parameter into a more
3464 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3468 end_template_parm_list (tree parms)
3472 tree saved_parmlist = make_tree_vec (list_length (parms));
3474 current_template_parms
3475 = tree_cons (size_int (processing_template_decl),
3476 saved_parmlist, current_template_parms);
3478 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3480 next = TREE_CHAIN (parm);
3481 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3482 TREE_CHAIN (parm) = NULL_TREE;
3485 --processing_template_parmlist;
3487 return saved_parmlist;
3490 /* end_template_decl is called after a template declaration is seen. */
3493 end_template_decl (void)
3495 reset_specialization ();
3497 if (! processing_template_decl)
3500 /* This matches the pushlevel in begin_template_parm_list. */
3503 --processing_template_decl;
3504 current_template_parms = TREE_CHAIN (current_template_parms);
3507 /* Within the declaration of a template, return all levels of template
3508 parameters that apply. The template parameters are represented as
3509 a TREE_VEC, in the form documented in cp-tree.h for template
3513 current_template_args (void)
3516 tree args = NULL_TREE;
3517 int length = TMPL_PARMS_DEPTH (current_template_parms);
3520 /* If there is only one level of template parameters, we do not
3521 create a TREE_VEC of TREE_VECs. Instead, we return a single
3522 TREE_VEC containing the arguments. */
3524 args = make_tree_vec (length);
3526 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3528 tree a = copy_node (TREE_VALUE (header));
3531 TREE_TYPE (a) = NULL_TREE;
3532 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3534 tree t = TREE_VEC_ELT (a, i);
3536 /* T will be a list if we are called from within a
3537 begin/end_template_parm_list pair, but a vector directly
3538 if within a begin/end_member_template_processing pair. */
3539 if (TREE_CODE (t) == TREE_LIST)
3543 if (!error_operand_p (t))
3545 if (TREE_CODE (t) == TYPE_DECL
3546 || TREE_CODE (t) == TEMPLATE_DECL)
3550 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3552 /* Turn this argument into a TYPE_ARGUMENT_PACK
3553 with a single element, which expands T. */
3554 tree vec = make_tree_vec (1);
3555 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3557 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3558 SET_ARGUMENT_PACK_ARGS (t, vec);
3563 t = DECL_INITIAL (t);
3565 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3567 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3568 with a single element, which expands T. */
3569 tree vec = make_tree_vec (1);
3570 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3571 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3573 t = make_node (NONTYPE_ARGUMENT_PACK);
3574 SET_ARGUMENT_PACK_ARGS (t, vec);
3575 TREE_TYPE (t) = type;
3578 TREE_VEC_ELT (a, i) = t;
3584 TREE_VEC_ELT (args, --l) = a;
3592 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3593 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3594 a member template. Used by push_template_decl below. */
3597 build_template_decl (tree decl, tree parms, bool member_template_p)
3599 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3600 DECL_TEMPLATE_PARMS (tmpl) = parms;
3601 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3602 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3607 struct template_parm_data
3609 /* The level of the template parameters we are currently
3613 /* The index of the specialization argument we are currently
3617 /* An array whose size is the number of template parameters. The
3618 elements are nonzero if the parameter has been used in any one
3619 of the arguments processed so far. */
3622 /* An array whose size is the number of template arguments. The
3623 elements are nonzero if the argument makes use of template
3624 parameters of this level. */
3625 int* arg_uses_template_parms;
3628 /* Subroutine of push_template_decl used to see if each template
3629 parameter in a partial specialization is used in the explicit
3630 argument list. If T is of the LEVEL given in DATA (which is
3631 treated as a template_parm_data*), then DATA->PARMS is marked
3635 mark_template_parm (tree t, void* data)
3639 struct template_parm_data* tpd = (struct template_parm_data*) data;
3641 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3643 level = TEMPLATE_PARM_LEVEL (t);
3644 idx = TEMPLATE_PARM_IDX (t);
3648 level = TEMPLATE_TYPE_LEVEL (t);
3649 idx = TEMPLATE_TYPE_IDX (t);
3652 if (level == tpd->level)
3654 tpd->parms[idx] = 1;
3655 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3658 /* Return zero so that for_each_template_parm will continue the
3659 traversal of the tree; we want to mark *every* template parm. */
3663 /* Process the partial specialization DECL. */
3666 process_partial_specialization (tree decl)
3668 tree type = TREE_TYPE (decl);
3669 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3670 tree specargs = CLASSTYPE_TI_ARGS (type);
3671 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3672 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3674 int nargs = TREE_VEC_LENGTH (inner_args);
3677 int did_error_intro = 0;
3678 struct template_parm_data tpd;
3679 struct template_parm_data tpd2;
3681 gcc_assert (current_template_parms);
3683 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3684 ntparms = TREE_VEC_LENGTH (inner_parms);
3686 /* We check that each of the template parameters given in the
3687 partial specialization is used in the argument list to the
3688 specialization. For example:
3690 template <class T> struct S;
3691 template <class T> struct S<T*>;
3693 The second declaration is OK because `T*' uses the template
3694 parameter T, whereas
3696 template <class T> struct S<int>;
3698 is no good. Even trickier is:
3709 The S2<T> declaration is actually invalid; it is a
3710 full-specialization. Of course,
3713 struct S2<T (*)(U)>;
3715 or some such would have been OK. */
3716 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3717 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3718 memset (tpd.parms, 0, sizeof (int) * ntparms);
3720 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3721 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3722 for (i = 0; i < nargs; ++i)
3724 tpd.current_arg = i;
3725 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3726 &mark_template_parm,
3729 /*include_nondeduced_p=*/false);
3731 for (i = 0; i < ntparms; ++i)
3732 if (tpd.parms[i] == 0)
3734 /* One of the template parms was not used in the
3736 if (!did_error_intro)
3738 error ("template parameters not used in partial specialization:");
3739 did_error_intro = 1;
3742 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3745 /* [temp.class.spec]
3747 The argument list of the specialization shall not be identical to
3748 the implicit argument list of the primary template. */
3749 if (comp_template_args
3751 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3753 error ("partial specialization %qT does not specialize any template arguments", type);
3755 /* [temp.class.spec]
3757 A partially specialized non-type argument expression shall not
3758 involve template parameters of the partial specialization except
3759 when the argument expression is a simple identifier.
3761 The type of a template parameter corresponding to a specialized
3762 non-type argument shall not be dependent on a parameter of the
3765 Also, we verify that pack expansions only occur at the
3766 end of the argument list. */
3767 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3769 for (i = 0; i < nargs; ++i)
3771 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3772 tree arg = TREE_VEC_ELT (inner_args, i);
3773 tree packed_args = NULL_TREE;
3776 if (ARGUMENT_PACK_P (arg))
3778 /* Extract the arguments from the argument pack. We'll be
3779 iterating over these in the following loop. */
3780 packed_args = ARGUMENT_PACK_ARGS (arg);
3781 len = TREE_VEC_LENGTH (packed_args);
3784 for (j = 0; j < len; j++)
3787 /* Get the Jth argument in the parameter pack. */
3788 arg = TREE_VEC_ELT (packed_args, j);
3790 if (PACK_EXPANSION_P (arg))
3792 /* Pack expansions must come at the end of the
3794 if ((packed_args && j < len - 1)
3795 || (!packed_args && i < nargs - 1))
3797 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3798 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3800 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3803 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3807 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3808 /* We only care about the pattern. */
3809 arg = PACK_EXPANSION_PATTERN (arg);
3811 if (/* These first two lines are the `non-type' bit. */
3813 && TREE_CODE (arg) != TEMPLATE_DECL
3814 /* This next line is the `argument expression is not just a
3815 simple identifier' condition and also the `specialized
3816 non-type argument' bit. */
3817 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3819 if ((!packed_args && tpd.arg_uses_template_parms[i])
3820 || (packed_args && uses_template_parms (arg)))
3821 error ("template argument %qE involves template parameter(s)",
3825 /* Look at the corresponding template parameter,
3826 marking which template parameters its type depends
3828 tree type = TREE_TYPE (parm);
3832 /* We haven't yet initialized TPD2. Do so now. */
3833 tpd2.arg_uses_template_parms
3834 = (int *) alloca (sizeof (int) * nargs);
3835 /* The number of parameters here is the number in the
3836 main template, which, as checked in the assertion
3838 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3840 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3843 /* Mark the template parameters. But this time, we're
3844 looking for the template parameters of the main
3845 template, not in the specialization. */
3846 tpd2.current_arg = i;
3847 tpd2.arg_uses_template_parms[i] = 0;
3848 memset (tpd2.parms, 0, sizeof (int) * nargs);
3849 for_each_template_parm (type,
3850 &mark_template_parm,
3853 /*include_nondeduced_p=*/false);
3855 if (tpd2.arg_uses_template_parms [i])
3857 /* The type depended on some template parameters.
3858 If they are fully specialized in the
3859 specialization, that's OK. */
3861 for (j = 0; j < nargs; ++j)
3862 if (tpd2.parms[j] != 0
3863 && tpd.arg_uses_template_parms [j])
3865 error ("type %qT of template argument %qE depends "
3866 "on template parameter(s)",
3877 /* We should only get here once. */
3878 gcc_assert (!COMPLETE_TYPE_P (type));
3880 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3881 = tree_cons (specargs, inner_parms,
3882 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3883 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3887 /* Check that a template declaration's use of default arguments and
3888 parameter packs is not invalid. Here, PARMS are the template
3889 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3890 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3894 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3895 declaration (but not a definition); 1 indicates a declaration, 2
3896 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3897 emitted for extraneous default arguments.
3899 Returns TRUE if there were no errors found, FALSE otherwise. */
3902 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3903 int is_partial, int is_friend_decl)
3906 int last_level_to_check;
3908 bool no_errors = true;
3912 A default template-argument shall not be specified in a
3913 function template declaration or a function template definition, nor
3914 in the template-parameter-list of the definition of a member of a
3917 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3918 /* You can't have a function template declaration in a local
3919 scope, nor you can you define a member of a class template in a
3923 if (current_class_type
3924 && !TYPE_BEING_DEFINED (current_class_type)
3925 && DECL_LANG_SPECIFIC (decl)
3926 && DECL_DECLARES_FUNCTION_P (decl)
3927 /* If this is either a friend defined in the scope of the class
3928 or a member function. */
3929 && (DECL_FUNCTION_MEMBER_P (decl)
3930 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3931 : DECL_FRIEND_CONTEXT (decl)
3932 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3934 /* And, if it was a member function, it really was defined in
3935 the scope of the class. */
3936 && (!DECL_FUNCTION_MEMBER_P (decl)
3937 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3938 /* We already checked these parameters when the template was
3939 declared, so there's no need to do it again now. This function
3940 was defined in class scope, but we're processing it's body now
3941 that the class is complete. */
3944 /* Core issue 226 (C++0x only): the following only applies to class
3946 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3950 If a template-parameter has a default template-argument, all
3951 subsequent template-parameters shall have a default
3952 template-argument supplied. */
3953 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3955 tree inner_parms = TREE_VALUE (parm_level);
3956 int ntparms = TREE_VEC_LENGTH (inner_parms);
3957 int seen_def_arg_p = 0;
3960 for (i = 0; i < ntparms; ++i)
3962 tree parm = TREE_VEC_ELT (inner_parms, i);
3964 if (parm == error_mark_node)
3967 if (TREE_PURPOSE (parm))
3969 else if (seen_def_arg_p
3970 && !template_parameter_pack_p (TREE_VALUE (parm)))
3972 error ("no default argument for %qD", TREE_VALUE (parm));
3973 /* For better subsequent error-recovery, we indicate that
3974 there should have been a default argument. */
3975 TREE_PURPOSE (parm) = error_mark_node;
3981 /* Don't complain about an enclosing partial
3983 && parm_level == parms
3984 && TREE_CODE (decl) == TYPE_DECL
3986 && template_parameter_pack_p (TREE_VALUE (parm)))
3988 /* A primary class template can only have one
3989 parameter pack, at the end of the template
3992 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3993 error ("parameter pack %qE must be at the end of the"
3994 " template parameter list", TREE_VALUE (parm));
3996 error ("parameter pack %qT must be at the end of the"
3997 " template parameter list",
3998 TREE_TYPE (TREE_VALUE (parm)));
4000 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4008 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4012 /* For an ordinary class template, default template arguments are
4013 allowed at the innermost level, e.g.:
4014 template <class T = int>
4016 but, in a partial specialization, they're not allowed even
4017 there, as we have in [temp.class.spec]:
4019 The template parameter list of a specialization shall not
4020 contain default template argument values.
4022 So, for a partial specialization, or for a function template
4023 (in C++98/C++03), we look at all of them. */
4026 /* But, for a primary class template that is not a partial
4027 specialization we look at all template parameters except the
4029 parms = TREE_CHAIN (parms);
4031 /* Figure out what error message to issue. */
4032 if (is_friend_decl == 2)
4033 msg = "default template arguments may not be used in function template friend re-declaration";
4034 else if (is_friend_decl)
4035 msg = "default template arguments may not be used in function template friend declarations";
4036 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4037 msg = ("default template arguments may not be used in function templates "
4038 "without -std=c++0x or -std=gnu++0x");
4039 else if (is_partial)
4040 msg = "default template arguments may not be used in partial specializations";
4042 msg = "default argument for template parameter for class enclosing %qD";
4044 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4045 /* If we're inside a class definition, there's no need to
4046 examine the parameters to the class itself. On the one
4047 hand, they will be checked when the class is defined, and,
4048 on the other, default arguments are valid in things like:
4049 template <class T = double>
4050 struct S { template <class U> void f(U); };
4051 Here the default argument for `S' has no bearing on the
4052 declaration of `f'. */
4053 last_level_to_check = template_class_depth (current_class_type) + 1;
4055 /* Check everything. */
4056 last_level_to_check = 0;
4058 for (parm_level = parms;
4059 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4060 parm_level = TREE_CHAIN (parm_level))
4062 tree inner_parms = TREE_VALUE (parm_level);
4066 ntparms = TREE_VEC_LENGTH (inner_parms);
4067 for (i = 0; i < ntparms; ++i)
4069 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4072 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4077 if (is_friend_decl == 2)
4084 /* Clear out the default argument so that we are not
4086 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4090 /* At this point, if we're still interested in issuing messages,
4091 they must apply to classes surrounding the object declared. */
4093 msg = "default argument for template parameter for class enclosing %qD";
4099 /* Worker for push_template_decl_real, called via
4100 for_each_template_parm. DATA is really an int, indicating the
4101 level of the parameters we are interested in. If T is a template
4102 parameter of that level, return nonzero. */
4105 template_parm_this_level_p (tree t, void* data)
4107 int this_level = *(int *)data;
4110 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4111 level = TEMPLATE_PARM_LEVEL (t);
4113 level = TEMPLATE_TYPE_LEVEL (t);
4114 return level == this_level;
4117 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4118 parameters given by current_template_args, or reuses a
4119 previously existing one, if appropriate. Returns the DECL, or an
4120 equivalent one, if it is replaced via a call to duplicate_decls.
4122 If IS_FRIEND is true, DECL is a friend declaration. */
4125 push_template_decl_real (tree decl, bool is_friend)
4133 int new_template_p = 0;
4134 /* True if the template is a member template, in the sense of
4136 bool member_template_p = false;
4138 if (decl == error_mark_node || !current_template_parms)
4139 return error_mark_node;
4141 /* See if this is a partial specialization. */
4142 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4143 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4144 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4146 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4150 /* For a friend, we want the context of the friend function, not
4151 the type of which it is a friend. */
4152 ctx = DECL_CONTEXT (decl);
4153 else if (CP_DECL_CONTEXT (decl)
4154 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4155 /* In the case of a virtual function, we want the class in which
4157 ctx = CP_DECL_CONTEXT (decl);
4159 /* Otherwise, if we're currently defining some class, the DECL
4160 is assumed to be a member of the class. */
4161 ctx = current_scope ();
4163 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4166 if (!DECL_CONTEXT (decl))
4167 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4169 /* See if this is a primary template. */
4170 if (is_friend && ctx)
4171 /* A friend template that specifies a class context, i.e.
4172 template <typename T> friend void A<T>::f();
4176 primary = template_parm_scope_p ();
4180 if (DECL_CLASS_SCOPE_P (decl))
4181 member_template_p = true;
4182 if (TREE_CODE (decl) == TYPE_DECL
4183 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4185 error ("template class without a name");
4186 return error_mark_node;
4188 else if (TREE_CODE (decl) == FUNCTION_DECL)
4190 if (DECL_DESTRUCTOR_P (decl))
4194 A destructor shall not be a member template. */
4195 error ("destructor %qD declared as member template", decl);
4196 return error_mark_node;
4198 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4199 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4200 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4201 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4202 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4203 == void_list_node)))
4205 /* [basic.stc.dynamic.allocation]
4207 An allocation function can be a function
4208 template. ... Template allocation functions shall
4209 have two or more parameters. */
4210 error ("invalid template declaration of %qD", decl);
4211 return error_mark_node;
4214 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4215 && CLASS_TYPE_P (TREE_TYPE (decl)))
4219 error ("template declaration of %q#D", decl);
4220 return error_mark_node;
4224 /* Check to see that the rules regarding the use of default
4225 arguments are not being violated. */
4226 check_default_tmpl_args (decl, current_template_parms,
4227 primary, is_partial, /*is_friend_decl=*/0);
4229 /* Ensure that there are no parameter packs in the type of this
4230 declaration that have not been expanded. */
4231 if (TREE_CODE (decl) == FUNCTION_DECL)
4233 /* Check each of the arguments individually to see if there are
4234 any bare parameter packs. */
4235 tree type = TREE_TYPE (decl);
4236 tree arg = DECL_ARGUMENTS (decl);
4237 tree argtype = TYPE_ARG_TYPES (type);
4239 while (arg && argtype)
4241 if (!FUNCTION_PARAMETER_PACK_P (arg)
4242 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4244 /* This is a PARM_DECL that contains unexpanded parameter
4245 packs. We have already complained about this in the
4246 check_for_bare_parameter_packs call, so just replace
4247 these types with ERROR_MARK_NODE. */
4248 TREE_TYPE (arg) = error_mark_node;
4249 TREE_VALUE (argtype) = error_mark_node;
4252 arg = TREE_CHAIN (arg);
4253 argtype = TREE_CHAIN (argtype);
4256 /* Check for bare parameter packs in the return type and the
4257 exception specifiers. */
4258 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4259 /* Errors were already issued, set return type to int
4260 as the frontend doesn't expect error_mark_node as
4262 TREE_TYPE (type) = integer_type_node;
4263 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4264 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4266 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4268 TREE_TYPE (decl) = error_mark_node;
4269 return error_mark_node;
4273 return process_partial_specialization (decl);
4275 args = current_template_args ();
4278 || TREE_CODE (ctx) == FUNCTION_DECL
4279 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4280 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4282 if (DECL_LANG_SPECIFIC (decl)
4283 && DECL_TEMPLATE_INFO (decl)
4284 && DECL_TI_TEMPLATE (decl))
4285 tmpl = DECL_TI_TEMPLATE (decl);
4286 /* If DECL is a TYPE_DECL for a class-template, then there won't
4287 be DECL_LANG_SPECIFIC. The information equivalent to
4288 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4289 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4290 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4291 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4293 /* Since a template declaration already existed for this
4294 class-type, we must be redeclaring it here. Make sure
4295 that the redeclaration is valid. */
4296 redeclare_class_template (TREE_TYPE (decl),
4297 current_template_parms);
4298 /* We don't need to create a new TEMPLATE_DECL; just use the
4299 one we already had. */
4300 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4304 tmpl = build_template_decl (decl, current_template_parms,
4308 if (DECL_LANG_SPECIFIC (decl)
4309 && DECL_TEMPLATE_SPECIALIZATION (decl))
4311 /* A specialization of a member template of a template
4313 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4314 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4315 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4321 tree a, t, current, parms;
4323 tree tinfo = get_template_info (decl);
4327 error ("template definition of non-template %q#D", decl);
4328 return error_mark_node;
4331 tmpl = TI_TEMPLATE (tinfo);
4333 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4334 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4335 && DECL_TEMPLATE_SPECIALIZATION (decl)
4336 && DECL_MEMBER_TEMPLATE_P (tmpl))
4340 /* The declaration is a specialization of a member
4341 template, declared outside the class. Therefore, the
4342 innermost template arguments will be NULL, so we
4343 replace them with the arguments determined by the
4344 earlier call to check_explicit_specialization. */
4345 args = DECL_TI_ARGS (decl);
4348 = build_template_decl (decl, current_template_parms,
4350 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4351 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4352 DECL_TI_TEMPLATE (decl) = new_tmpl;
4353 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4354 DECL_TEMPLATE_INFO (new_tmpl)
4355 = tree_cons (tmpl, args, NULL_TREE);
4357 register_specialization (new_tmpl,
4358 most_general_template (tmpl),
4364 /* Make sure the template headers we got make sense. */
4366 parms = DECL_TEMPLATE_PARMS (tmpl);
4367 i = TMPL_PARMS_DEPTH (parms);
4368 if (TMPL_ARGS_DEPTH (args) != i)
4370 error ("expected %d levels of template parms for %q#D, got %d",
4371 i, decl, TMPL_ARGS_DEPTH (args));
4374 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4376 a = TMPL_ARGS_LEVEL (args, i);
4377 t = INNERMOST_TEMPLATE_PARMS (parms);
4379 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4381 if (current == decl)
4382 error ("got %d template parameters for %q#D",
4383 TREE_VEC_LENGTH (a), decl);
4385 error ("got %d template parameters for %q#T",
4386 TREE_VEC_LENGTH (a), current);
4387 error (" but %d required", TREE_VEC_LENGTH (t));
4388 return error_mark_node;
4391 if (current == decl)
4394 current = (TYPE_P (current)
4395 ? TYPE_CONTEXT (current)
4396 : DECL_CONTEXT (current));
4399 /* Check that the parms are used in the appropriate qualifying scopes
4400 in the declarator. */
4401 if (!comp_template_args
4403 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4406 template arguments to %qD do not match original template %qD",
4407 decl, DECL_TEMPLATE_RESULT (tmpl));
4408 if (!uses_template_parms (TI_ARGS (tinfo)))
4409 inform (input_location, "use template<> for an explicit specialization");
4410 /* Avoid crash in import_export_decl. */
4411 DECL_INTERFACE_KNOWN (decl) = 1;
4412 return error_mark_node;
4416 DECL_TEMPLATE_RESULT (tmpl) = decl;
4417 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4419 /* Push template declarations for global functions and types. Note
4420 that we do not try to push a global template friend declared in a
4421 template class; such a thing may well depend on the template
4422 parameters of the class. */
4423 if (new_template_p && !ctx
4424 && !(is_friend && template_class_depth (current_class_type) > 0))
4426 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4427 if (tmpl == error_mark_node)
4428 return error_mark_node;
4430 /* Hide template friend classes that haven't been declared yet. */
4431 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4433 DECL_ANTICIPATED (tmpl) = 1;
4434 DECL_FRIEND_P (tmpl) = 1;
4440 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4443 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4444 if (DECL_CONV_FN_P (tmpl))
4446 int depth = TMPL_PARMS_DEPTH (parms);
4448 /* It is a conversion operator. See if the type converted to
4449 depends on innermost template operands. */
4451 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4453 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4456 /* Give template template parms a DECL_CONTEXT of the template
4457 for which they are a parameter. */
4458 parms = INNERMOST_TEMPLATE_PARMS (parms);
4459 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4461 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4462 if (TREE_CODE (parm) == TEMPLATE_DECL)
4463 DECL_CONTEXT (parm) = tmpl;
4467 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4468 back to its most general template. If TMPL is a specialization,
4469 ARGS may only have the innermost set of arguments. Add the missing
4470 argument levels if necessary. */
4471 if (DECL_TEMPLATE_INFO (tmpl))
4472 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4474 info = tree_cons (tmpl, args, NULL_TREE);
4476 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4477 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4478 else if (DECL_LANG_SPECIFIC (decl))
4479 DECL_TEMPLATE_INFO (decl) = info;
4481 return DECL_TEMPLATE_RESULT (tmpl);
4485 push_template_decl (tree decl)
4487 return push_template_decl_real (decl, false);
4490 /* Called when a class template TYPE is redeclared with the indicated
4491 template PARMS, e.g.:
4493 template <class T> struct S;
4494 template <class T> struct S {}; */
4497 redeclare_class_template (tree type, tree parms)
4503 if (!TYPE_TEMPLATE_INFO (type))
4505 error ("%qT is not a template type", type);
4509 tmpl = TYPE_TI_TEMPLATE (type);
4510 if (!PRIMARY_TEMPLATE_P (tmpl))
4511 /* The type is nested in some template class. Nothing to worry
4512 about here; there are no new template parameters for the nested
4518 error ("template specifiers not specified in declaration of %qD",
4523 parms = INNERMOST_TEMPLATE_PARMS (parms);
4524 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4526 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4528 error ("redeclared with %d template parameter(s)",
4529 TREE_VEC_LENGTH (parms));
4530 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4531 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4535 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4542 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4543 || TREE_VEC_ELT (parms, i) == error_mark_node)
4546 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4547 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4548 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4549 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4551 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4553 if (tmpl_parm != error_mark_node
4554 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4555 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4556 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4557 || (TREE_CODE (tmpl_parm) != PARM_DECL
4558 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4559 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4560 || (TREE_CODE (tmpl_parm) == PARM_DECL
4561 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4562 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4564 error ("template parameter %q+#D", tmpl_parm);
4565 error ("redeclared here as %q#D", parm);
4569 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4571 /* We have in [temp.param]:
4573 A template-parameter may not be given default arguments
4574 by two different declarations in the same scope. */
4575 error_at (input_location, "redefinition of default argument for %q#D", parm);
4576 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4577 "original definition appeared here");
4581 if (parm_default != NULL_TREE)
4582 /* Update the previous template parameters (which are the ones
4583 that will really count) with the new default value. */
4584 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4585 else if (tmpl_default != NULL_TREE)
4586 /* Update the new parameters, too; they'll be used as the
4587 parameters for any members. */
4588 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4594 /* Simplify EXPR if it is a non-dependent expression. Returns the
4595 (possibly simplified) expression. */
4598 fold_non_dependent_expr (tree expr)
4600 if (expr == NULL_TREE)
4603 /* If we're in a template, but EXPR isn't value dependent, simplify
4604 it. We're supposed to treat:
4606 template <typename T> void f(T[1 + 1]);
4607 template <typename T> void f(T[2]);
4609 as two declarations of the same function, for example. */
4610 if (processing_template_decl
4611 && !type_dependent_expression_p (expr)
4612 && !value_dependent_expression_p (expr))
4614 HOST_WIDE_INT saved_processing_template_decl;
4616 saved_processing_template_decl = processing_template_decl;
4617 processing_template_decl = 0;
4618 expr = tsubst_copy_and_build (expr,
4621 /*in_decl=*/NULL_TREE,
4622 /*function_p=*/false,
4623 /*integral_constant_expression_p=*/true);
4624 processing_template_decl = saved_processing_template_decl;
4629 /* EXPR is an expression which is used in a constant-expression context.
4630 For instance, it could be a VAR_DECL with a constant initializer.
4631 Extract the innermost constant expression.
4633 This is basically a more powerful version of
4634 integral_constant_value, which can be used also in templates where
4635 initializers can maintain a syntactic rather than semantic form
4636 (even if they are non-dependent, for access-checking purposes). */
4639 fold_decl_constant_value (tree expr)
4641 tree const_expr = expr;
4644 expr = fold_non_dependent_expr (const_expr);
4645 const_expr = integral_constant_value (expr);
4647 while (expr != const_expr);
4652 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4653 must be a function or a pointer-to-function type, as specified
4654 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4655 and check that the resulting function has external linkage. */
4658 convert_nontype_argument_function (tree type, tree expr)
4663 fn = instantiate_type (type, fns, tf_none);
4664 if (fn == error_mark_node)
4665 return error_mark_node;
4668 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4669 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4670 if (TREE_CODE (fn_no_ptr) == BASELINK)
4671 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4673 /* [temp.arg.nontype]/1
4675 A template-argument for a non-type, non-template template-parameter
4678 -- the address of an object or function with external linkage. */
4679 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4681 error ("%qE is not a valid template argument for type %qT "
4682 "because function %qD has not external linkage",
4683 expr, type, fn_no_ptr);
4690 /* Subroutine of convert_nontype_argument.
4691 Check if EXPR of type TYPE is a valid pointer-to-member constant.
4692 Emit an error otherwise. */
4695 check_valid_ptrmem_cst_expr (tree type, tree expr)
4698 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
4700 error ("%qE is not a valid template argument for type %qT",
4702 error ("it must be a pointer-to-member of the form `&X::Y'");
4706 /* Attempt to convert the non-type template parameter EXPR to the
4707 indicated TYPE. If the conversion is successful, return the
4708 converted value. If the conversion is unsuccessful, return
4709 NULL_TREE if we issued an error message, or error_mark_node if we
4710 did not. We issue error messages for out-and-out bad template
4711 parameters, but not simply because the conversion failed, since we
4712 might be just trying to do argument deduction. Both TYPE and EXPR
4713 must be non-dependent.
4715 The conversion follows the special rules described in
4716 [temp.arg.nontype], and it is much more strict than an implicit
4719 This function is called twice for each template argument (see
4720 lookup_template_class for a more accurate description of this
4721 problem). This means that we need to handle expressions which
4722 are not valid in a C++ source, but can be created from the
4723 first call (for instance, casts to perform conversions). These
4724 hacks can go away after we fix the double coercion problem. */
4727 convert_nontype_argument (tree type, tree expr)
4731 /* Detect immediately string literals as invalid non-type argument.
4732 This special-case is not needed for correctness (we would easily
4733 catch this later), but only to provide better diagnostic for this
4734 common user mistake. As suggested by DR 100, we do not mention
4735 linkage issues in the diagnostic as this is not the point. */
4736 if (TREE_CODE (expr) == STRING_CST)
4738 error ("%qE is not a valid template argument for type %qT "
4739 "because string literals can never be used in this context",
4744 /* If we are in a template, EXPR may be non-dependent, but still
4745 have a syntactic, rather than semantic, form. For example, EXPR
4746 might be a SCOPE_REF, rather than the VAR_DECL to which the
4747 SCOPE_REF refers. Preserving the qualifying scope is necessary
4748 so that access checking can be performed when the template is
4749 instantiated -- but here we need the resolved form so that we can
4750 convert the argument. */
4751 expr = fold_non_dependent_expr (expr);
4752 if (error_operand_p (expr))
4753 return error_mark_node;
4754 expr_type = TREE_TYPE (expr);
4756 /* HACK: Due to double coercion, we can get a
4757 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4758 which is the tree that we built on the first call (see
4759 below when coercing to reference to object or to reference to
4760 function). We just strip everything and get to the arg.
4761 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4763 if (TREE_CODE (expr) == NOP_EXPR)
4765 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4767 /* ??? Maybe we could use convert_from_reference here, but we
4768 would need to relax its constraints because the NOP_EXPR
4769 could actually change the type to something more cv-qualified,
4770 and this is not folded by convert_from_reference. */
4771 tree addr = TREE_OPERAND (expr, 0);
4772 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4773 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4774 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4775 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4776 (TREE_TYPE (expr_type),
4777 TREE_TYPE (TREE_TYPE (addr))));
4779 expr = TREE_OPERAND (addr, 0);
4780 expr_type = TREE_TYPE (expr);
4783 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4784 parameter is a pointer to object, through decay and
4785 qualification conversion. Let's strip everything. */
4786 else if (TYPE_PTROBV_P (type))
4789 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4790 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4791 /* Skip the ADDR_EXPR only if it is part of the decay for
4792 an array. Otherwise, it is part of the original argument
4793 in the source code. */
4794 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4795 expr = TREE_OPERAND (expr, 0);
4796 expr_type = TREE_TYPE (expr);
4800 /* [temp.arg.nontype]/5, bullet 1
4802 For a non-type template-parameter of integral or enumeration type,
4803 integral promotions (_conv.prom_) and integral conversions
4804 (_conv.integral_) are applied. */
4805 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4807 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4808 return error_mark_node;
4810 expr = fold_decl_constant_value (expr);
4811 /* Notice that there are constant expressions like '4 % 0' which
4812 do not fold into integer constants. */
4813 if (TREE_CODE (expr) != INTEGER_CST)
4815 error ("%qE is not a valid template argument for type %qT "
4816 "because it is a non-constant expression", expr, type);
4820 /* At this point, an implicit conversion does what we want,
4821 because we already know that the expression is of integral
4823 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4824 if (expr == error_mark_node)
4825 return error_mark_node;
4827 /* Conversion was allowed: fold it to a bare integer constant. */
4830 /* [temp.arg.nontype]/5, bullet 2
4832 For a non-type template-parameter of type pointer to object,
4833 qualification conversions (_conv.qual_) and the array-to-pointer
4834 conversion (_conv.array_) are applied. */
4835 else if (TYPE_PTROBV_P (type))
4837 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4839 A template-argument for a non-type, non-template template-parameter
4840 shall be one of: [...]
4842 -- the name of a non-type template-parameter;
4843 -- the address of an object or function with external linkage, [...]
4844 expressed as "& id-expression" where the & is optional if the name
4845 refers to a function or array, or if the corresponding
4846 template-parameter is a reference.
4848 Here, we do not care about functions, as they are invalid anyway
4849 for a parameter of type pointer-to-object. */
4851 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4852 /* Non-type template parameters are OK. */
4854 else if (TREE_CODE (expr) != ADDR_EXPR
4855 && TREE_CODE (expr_type) != ARRAY_TYPE)
4857 if (TREE_CODE (expr) == VAR_DECL)
4859 error ("%qD is not a valid template argument "
4860 "because %qD is a variable, not the address of "
4865 /* Other values, like integer constants, might be valid
4866 non-type arguments of some other type. */
4867 return error_mark_node;
4873 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4874 ? TREE_OPERAND (expr, 0) : expr);
4875 if (TREE_CODE (decl) != VAR_DECL)
4877 error ("%qE is not a valid template argument of type %qT "
4878 "because %qE is not a variable",
4882 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4884 error ("%qE is not a valid template argument of type %qT "
4885 "because %qD does not have external linkage",
4891 expr = decay_conversion (expr);
4892 if (expr == error_mark_node)
4893 return error_mark_node;
4895 expr = perform_qualification_conversions (type, expr);
4896 if (expr == error_mark_node)
4897 return error_mark_node;
4899 /* [temp.arg.nontype]/5, bullet 3
4901 For a non-type template-parameter of type reference to object, no
4902 conversions apply. The type referred to by the reference may be more
4903 cv-qualified than the (otherwise identical) type of the
4904 template-argument. The template-parameter is bound directly to the
4905 template-argument, which must be an lvalue. */
4906 else if (TYPE_REF_OBJ_P (type))
4908 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4910 return error_mark_node;
4912 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4914 error ("%qE is not a valid template argument for type %qT "
4915 "because of conflicts in cv-qualification", expr, type);
4919 if (!real_lvalue_p (expr))
4921 error ("%qE is not a valid template argument for type %qT "
4922 "because it is not an lvalue", expr, type);
4926 /* [temp.arg.nontype]/1
4928 A template-argument for a non-type, non-template template-parameter
4929 shall be one of: [...]
4931 -- the address of an object or function with external linkage. */
4932 if (TREE_CODE (expr) == INDIRECT_REF
4933 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
4935 expr = TREE_OPERAND (expr, 0);
4938 error ("%q#D is not a valid template argument for type %qT "
4939 "because a reference variable does not have a constant "
4940 "address", expr, type);
4947 error ("%qE is not a valid template argument for type %qT "
4948 "because it is not an object with external linkage",
4953 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4955 error ("%qE is not a valid template argument for type %qT "
4956 "because object %qD has not external linkage",
4961 expr = build_nop (type, build_address (expr));
4963 /* [temp.arg.nontype]/5, bullet 4
4965 For a non-type template-parameter of type pointer to function, only
4966 the function-to-pointer conversion (_conv.func_) is applied. If the
4967 template-argument represents a set of overloaded functions (or a
4968 pointer to such), the matching function is selected from the set
4970 else if (TYPE_PTRFN_P (type))
4972 /* If the argument is a template-id, we might not have enough
4973 context information to decay the pointer. */
4974 if (!type_unknown_p (expr_type))
4976 expr = decay_conversion (expr);
4977 if (expr == error_mark_node)
4978 return error_mark_node;
4981 expr = convert_nontype_argument_function (type, expr);
4982 if (!expr || expr == error_mark_node)
4985 if (TREE_CODE (expr) != ADDR_EXPR)
4987 error ("%qE is not a valid template argument for type %qT", expr, type);
4988 error ("it must be the address of a function with external linkage");
4992 /* [temp.arg.nontype]/5, bullet 5
4994 For a non-type template-parameter of type reference to function, no
4995 conversions apply. If the template-argument represents a set of
4996 overloaded functions, the matching function is selected from the set
4998 else if (TYPE_REFFN_P (type))
5000 if (TREE_CODE (expr) == ADDR_EXPR)
5002 error ("%qE is not a valid template argument for type %qT "
5003 "because it is a pointer", expr, type);
5004 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5008 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5009 if (!expr || expr == error_mark_node)
5012 expr = build_nop (type, build_address (expr));
5014 /* [temp.arg.nontype]/5, bullet 6
5016 For a non-type template-parameter of type pointer to member function,
5017 no conversions apply. If the template-argument represents a set of
5018 overloaded member functions, the matching member function is selected
5019 from the set (_over.over_). */
5020 else if (TYPE_PTRMEMFUNC_P (type))
5022 expr = instantiate_type (type, expr, tf_none);
5023 if (expr == error_mark_node)
5024 return error_mark_node;
5026 /* [temp.arg.nontype] bullet 1 says the pointer to member
5027 expression must be a pointer-to-member constant. */
5028 if (!check_valid_ptrmem_cst_expr (type, expr))
5029 return error_mark_node;
5031 /* There is no way to disable standard conversions in
5032 resolve_address_of_overloaded_function (called by
5033 instantiate_type). It is possible that the call succeeded by
5034 converting &B::I to &D::I (where B is a base of D), so we need
5035 to reject this conversion here.
5037 Actually, even if there was a way to disable standard conversions,
5038 it would still be better to reject them here so that we can
5039 provide a superior diagnostic. */
5040 if (!same_type_p (TREE_TYPE (expr), type))
5042 /* Make sure we are just one standard conversion off. */
5043 gcc_assert (can_convert (type, TREE_TYPE (expr)));
5044 error ("%qE is not a valid template argument for type %qT "
5045 "because it is of type %qT", expr, type,
5047 inform (input_location, "standard conversions are not allowed in this context");
5051 /* [temp.arg.nontype]/5, bullet 7
5053 For a non-type template-parameter of type pointer to data member,
5054 qualification conversions (_conv.qual_) are applied. */
5055 else if (TYPE_PTRMEM_P (type))
5057 /* [temp.arg.nontype] bullet 1 says the pointer to member
5058 expression must be a pointer-to-member constant. */
5059 if (!check_valid_ptrmem_cst_expr (type, expr))
5060 return error_mark_node;
5062 expr = perform_qualification_conversions (type, expr);
5063 if (expr == error_mark_node)
5066 /* A template non-type parameter must be one of the above. */
5070 /* Sanity check: did we actually convert the argument to the
5072 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
5076 /* Subroutine of coerce_template_template_parms, which returns 1 if
5077 PARM_PARM and ARG_PARM match using the rule for the template
5078 parameters of template template parameters. Both PARM and ARG are
5079 template parameters; the rest of the arguments are the same as for
5080 coerce_template_template_parms.
5083 coerce_template_template_parm (tree parm,
5085 tsubst_flags_t complain,
5089 if (arg == NULL_TREE || arg == error_mark_node
5090 || parm == NULL_TREE || parm == error_mark_node)
5093 if (TREE_CODE (arg) != TREE_CODE (parm))
5096 switch (TREE_CODE (parm))
5099 /* We encounter instantiations of templates like
5100 template <template <template <class> class> class TT>
5103 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5104 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5106 if (!coerce_template_template_parms
5107 (parmparm, argparm, complain, in_decl, outer_args))
5113 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5114 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5115 /* Argument is a parameter pack but parameter is not. */
5120 /* The tsubst call is used to handle cases such as
5122 template <int> class C {};
5123 template <class T, template <T> class TT> class D {};
5126 i.e. the parameter list of TT depends on earlier parameters. */
5127 if (!uses_template_parms (TREE_TYPE (arg))
5129 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5133 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5134 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5135 /* Argument is a parameter pack but parameter is not. */
5148 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5149 template template parameters. Both PARM_PARMS and ARG_PARMS are
5150 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5153 Consider the example:
5154 template <class T> class A;
5155 template<template <class U> class TT> class B;
5157 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5158 the parameters to A, and OUTER_ARGS contains A. */
5161 coerce_template_template_parms (tree parm_parms,
5163 tsubst_flags_t complain,
5167 int nparms, nargs, i;
5171 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5172 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5174 nparms = TREE_VEC_LENGTH (parm_parms);
5175 nargs = TREE_VEC_LENGTH (arg_parms);
5177 /* Determine whether we have a parameter pack at the end of the
5178 template template parameter's template parameter list. */
5179 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5181 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5183 if (parm == error_mark_node)
5186 switch (TREE_CODE (parm))
5190 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5195 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5205 && !(variadic_p && nargs >= nparms - 1))
5208 /* Check all of the template parameters except the parameter pack at
5209 the end (if any). */
5210 for (i = 0; i < nparms - variadic_p; ++i)
5212 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5213 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5216 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5217 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5219 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5227 /* Check each of the template parameters in the template
5228 argument against the template parameter pack at the end of
5229 the template template parameter. */
5230 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5233 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5235 for (; i < nargs; ++i)
5237 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5240 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5242 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5251 /* Verifies that the deduced template arguments (in TARGS) for the
5252 template template parameters (in TPARMS) represent valid bindings,
5253 by comparing the template parameter list of each template argument
5254 to the template parameter list of its corresponding template
5255 template parameter, in accordance with DR150. This
5256 routine can only be called after all template arguments have been
5257 deduced. It will return TRUE if all of the template template
5258 parameter bindings are okay, FALSE otherwise. */
5260 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5262 int i, ntparms = TREE_VEC_LENGTH (tparms);
5265 /* We're dealing with template parms in this process. */
5266 ++processing_template_decl;
5268 targs = INNERMOST_TEMPLATE_ARGS (targs);
5270 for (i = 0; i < ntparms; ++i)
5272 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5273 tree targ = TREE_VEC_ELT (targs, i);
5275 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5277 tree packed_args = NULL_TREE;
5280 if (ARGUMENT_PACK_P (targ))
5282 /* Look inside the argument pack. */
5283 packed_args = ARGUMENT_PACK_ARGS (targ);
5284 len = TREE_VEC_LENGTH (packed_args);
5287 for (idx = 0; idx < len; ++idx)
5289 tree targ_parms = NULL_TREE;
5292 /* Extract the next argument from the argument
5294 targ = TREE_VEC_ELT (packed_args, idx);
5296 if (PACK_EXPANSION_P (targ))
5297 /* Look at the pattern of the pack expansion. */
5298 targ = PACK_EXPANSION_PATTERN (targ);
5300 /* Extract the template parameters from the template
5302 if (TREE_CODE (targ) == TEMPLATE_DECL)
5303 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5304 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5305 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5307 /* Verify that we can coerce the template template
5308 parameters from the template argument to the template
5309 parameter. This requires an exact match. */
5311 && !coerce_template_template_parms
5312 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5327 --processing_template_decl;
5331 /* Convert the indicated template ARG as necessary to match the
5332 indicated template PARM. Returns the converted ARG, or
5333 error_mark_node if the conversion was unsuccessful. Error and
5334 warning messages are issued under control of COMPLAIN. This
5335 conversion is for the Ith parameter in the parameter list. ARGS is
5336 the full set of template arguments deduced so far. */
5339 convert_template_argument (tree parm,
5342 tsubst_flags_t complain,
5348 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5350 if (TREE_CODE (arg) == TREE_LIST
5351 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5353 /* The template argument was the name of some
5354 member function. That's usually
5355 invalid, but static members are OK. In any
5356 case, grab the underlying fields/functions
5357 and issue an error later if required. */
5358 orig_arg = TREE_VALUE (arg);
5359 TREE_TYPE (arg) = unknown_type_node;
5364 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5365 requires_type = (TREE_CODE (parm) == TYPE_DECL
5366 || requires_tmpl_type);
5368 /* When determining whether an argument pack expansion is a template,
5369 look at the pattern. */
5370 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5371 arg = PACK_EXPANSION_PATTERN (arg);
5374 ((TREE_CODE (arg) == TEMPLATE_DECL
5375 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5376 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5377 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5380 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5381 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5382 arg = TYPE_STUB_DECL (arg);
5384 is_type = TYPE_P (arg) || is_tmpl_type;
5386 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5387 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5389 permerror (input_location, "to refer to a type member of a template parameter, "
5390 "use %<typename %E%>", orig_arg);
5392 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5393 TREE_OPERAND (arg, 1),
5395 complain & tf_error);
5399 if (is_type != requires_type)
5403 if (complain & tf_error)
5405 error ("type/value mismatch at argument %d in template "
5406 "parameter list for %qD",
5409 error (" expected a constant of type %qT, got %qT",
5411 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5412 else if (requires_tmpl_type)
5413 error (" expected a class template, got %qE", orig_arg);
5415 error (" expected a type, got %qE", orig_arg);
5418 return error_mark_node;
5420 if (is_tmpl_type ^ requires_tmpl_type)
5422 if (in_decl && (complain & tf_error))
5424 error ("type/value mismatch at argument %d in template "
5425 "parameter list for %qD",
5428 error (" expected a type, got %qT", DECL_NAME (arg));
5430 error (" expected a class template, got %qT", orig_arg);
5432 return error_mark_node;
5437 if (requires_tmpl_type)
5439 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5440 /* The number of argument required is not known yet.
5441 Just accept it for now. */
5442 val = TREE_TYPE (arg);
5445 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5448 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5450 if (coerce_template_template_parms (parmparm, argparm,
5456 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5458 if (val != error_mark_node)
5460 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5461 val = TREE_TYPE (val);
5462 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
5463 val = make_pack_expansion (val);
5468 if (in_decl && (complain & tf_error))
5470 error ("type/value mismatch at argument %d in "
5471 "template parameter list for %qD",
5473 error (" expected a template of type %qD, got %qT",
5477 val = error_mark_node;
5483 /* We only form one instance of each template specialization.
5484 Therefore, if we use a non-canonical variant (i.e., a
5485 typedef), any future messages referring to the type will use
5486 the typedef, which is confusing if those future uses do not
5487 themselves also use the typedef. */
5489 val = strip_typedefs (val);
5493 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5495 if (invalid_nontype_parm_type_p (t, complain))
5496 return error_mark_node;
5498 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5500 if (same_type_p (t, TREE_TYPE (orig_arg)))
5504 /* Not sure if this is reachable, but it doesn't hurt
5506 error ("type mismatch in nontype parameter pack");
5507 val = error_mark_node;
5510 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5511 /* We used to call digest_init here. However, digest_init
5512 will report errors, which we don't want when complain
5513 is zero. More importantly, digest_init will try too
5514 hard to convert things: for example, `0' should not be
5515 converted to pointer type at this point according to
5516 the standard. Accepting this is not merely an
5517 extension, since deciding whether or not these
5518 conversions can occur is part of determining which
5519 function template to call, or whether a given explicit
5520 argument specification is valid. */
5521 val = convert_nontype_argument (t, orig_arg);
5525 if (val == NULL_TREE)
5526 val = error_mark_node;
5527 else if (val == error_mark_node && (complain & tf_error))
5528 error ("could not convert template argument %qE to %qT", orig_arg, t);
5534 /* Coerces the remaining template arguments in INNER_ARGS (from
5535 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5536 Returns the coerced argument pack. PARM_IDX is the position of this
5537 parameter in the template parameter list. ARGS is the original
5538 template argument list. */
5540 coerce_template_parameter_pack (tree parms,
5548 tsubst_flags_t complain)
5550 tree parm = TREE_VEC_ELT (parms, parm_idx);
5551 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5554 tree packed_types = NULL_TREE;
5556 if (arg_idx > nargs)
5559 packed_args = make_tree_vec (nargs - arg_idx);
5561 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5562 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5564 /* When the template parameter is a non-type template
5565 parameter pack whose type uses parameter packs, we need
5566 to look at each of the template arguments
5567 separately. Build a vector of the types for these
5568 non-type template parameters in PACKED_TYPES. */
5570 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5571 packed_types = tsubst_pack_expansion (expansion, args,
5574 if (packed_types == error_mark_node)
5575 return error_mark_node;
5577 /* Check that we have the right number of arguments. */
5579 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5580 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5583 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5584 error ("wrong number of template arguments (%d, should be %d)",
5585 nargs, needed_parms);
5586 return error_mark_node;
5589 /* If we aren't able to check the actual arguments now
5590 (because they haven't been expanded yet), we can at least
5591 verify that all of the types used for the non-type
5592 template parameter pack are, in fact, valid for non-type
5593 template parameters. */
5595 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5597 int j, len = TREE_VEC_LENGTH (packed_types);
5598 for (j = 0; j < len; ++j)
5600 tree t = TREE_VEC_ELT (packed_types, j);
5601 if (invalid_nontype_parm_type_p (t, complain))
5602 return error_mark_node;
5607 /* Convert the remaining arguments, which will be a part of the
5608 parameter pack "parm". */
5609 for (; arg_idx < nargs; ++arg_idx)
5611 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5612 tree actual_parm = TREE_VALUE (parm);
5614 if (packed_types && !PACK_EXPANSION_P (arg))
5616 /* When we have a vector of types (corresponding to the
5617 non-type template parameter pack that uses parameter
5618 packs in its type, as mention above), and the
5619 argument is not an expansion (which expands to a
5620 currently unknown number of arguments), clone the
5621 parm and give it the next type in PACKED_TYPES. */
5622 actual_parm = copy_node (actual_parm);
5623 TREE_TYPE (actual_parm) =
5624 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5627 if (arg != error_mark_node)
5628 arg = convert_template_argument (actual_parm,
5629 arg, new_args, complain, parm_idx,
5631 if (arg == error_mark_node)
5633 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5636 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5637 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5638 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
5641 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5642 TREE_TYPE (argument_pack)
5643 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5644 TREE_CONSTANT (argument_pack) = 1;
5647 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5648 return argument_pack;
5651 /* Convert all template arguments to their appropriate types, and
5652 return a vector containing the innermost resulting template
5653 arguments. If any error occurs, return error_mark_node. Error and
5654 warning messages are issued under control of COMPLAIN.
5656 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5657 for arguments not specified in ARGS. Otherwise, if
5658 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5659 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5660 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5664 coerce_template_parms (tree parms,
5667 tsubst_flags_t complain,
5668 bool require_all_args,
5669 bool use_default_args)
5671 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5674 tree new_inner_args;
5675 int saved_unevaluated_operand;
5676 int saved_inhibit_evaluation_warnings;
5678 /* When used as a boolean value, indicates whether this is a
5679 variadic template parameter list. Since it's an int, we can also
5680 subtract it from nparms to get the number of non-variadic
5684 nparms = TREE_VEC_LENGTH (parms);
5686 /* Determine if there are any parameter packs. */
5687 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5689 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5690 if (template_parameter_pack_p (tparm))
5694 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5695 /* If there are 0 or 1 parameter packs, we need to expand any argument
5696 packs so that we can deduce a parameter pack from some non-packed args
5697 followed by an argument pack, as in variadic85.C. If there are more
5698 than that, we need to leave argument packs intact so the arguments are
5699 assigned to the right parameter packs. This should only happen when
5700 dealing with a nested class inside a partial specialization of a class
5701 template, as in variadic92.C. */
5702 if (variadic_p <= 1)
5703 inner_args = expand_template_argument_pack (inner_args);
5705 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5706 if ((nargs > nparms && !variadic_p)
5707 || (nargs < nparms - variadic_p
5709 && (!use_default_args
5710 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5711 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5713 if (complain & tf_error)
5715 const char *or_more = "";
5718 or_more = " or more";
5722 error ("wrong number of template arguments (%d, should be %d%s)",
5723 nargs, nparms, or_more);
5726 error ("provided for %q+D", in_decl);
5729 return error_mark_node;
5732 /* We need to evaluate the template arguments, even though this
5733 template-id may be nested within a "sizeof". */
5734 saved_unevaluated_operand = cp_unevaluated_operand;
5735 cp_unevaluated_operand = 0;
5736 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5737 c_inhibit_evaluation_warnings = 0;
5738 new_inner_args = make_tree_vec (nparms);
5739 new_args = add_outermost_template_args (args, new_inner_args);
5740 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5745 /* Get the Ith template parameter. */
5746 parm = TREE_VEC_ELT (parms, parm_idx);
5748 if (parm == error_mark_node)
5750 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5754 /* Calculate the next argument. */
5755 if (arg_idx < nargs)
5756 arg = TREE_VEC_ELT (inner_args, arg_idx);
5760 if (template_parameter_pack_p (TREE_VALUE (parm))
5761 && !(arg && ARGUMENT_PACK_P (arg)))
5763 /* All remaining arguments will be placed in the
5764 template parameter pack PARM. */
5765 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5766 inner_args, arg_idx,
5770 /* Store this argument. */
5771 if (arg == error_mark_node)
5773 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5775 /* We are done with all of the arguments. */
5782 if (PACK_EXPANSION_P (arg))
5784 if (complain & tf_error)
5786 /* FIXME this restriction was removed by N2555; see
5788 /* If ARG is a pack expansion, but PARM is not a
5789 template parameter pack (if it were, we would have
5790 handled it above), we're trying to expand into a
5791 fixed-length argument list. */
5792 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5793 sorry ("cannot expand %<%E%> into a fixed-length "
5794 "argument list", arg);
5796 sorry ("cannot expand %<%T%> into a fixed-length "
5797 "argument list", arg);
5799 return error_mark_node;
5802 else if (require_all_args)
5803 /* There must be a default arg in this case. */
5804 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5809 if (arg == error_mark_node)
5811 if (complain & tf_error)
5812 error ("template argument %d is invalid", arg_idx + 1);
5815 /* This only occurs if there was an error in the template
5816 parameter list itself (which we would already have
5817 reported) that we are trying to recover from, e.g., a class
5818 template with a parameter list such as
5819 template<typename..., typename>. */
5820 return error_mark_node;
5822 arg = convert_template_argument (TREE_VALUE (parm),
5823 arg, new_args, complain,
5826 if (arg == error_mark_node)
5828 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5830 cp_unevaluated_operand = saved_unevaluated_operand;
5831 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
5834 return error_mark_node;
5836 return new_inner_args;
5839 /* Returns 1 if template args OT and NT are equivalent. */
5842 template_args_equal (tree ot, tree nt)
5847 if (TREE_CODE (nt) == TREE_VEC)
5848 /* For member templates */
5849 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5850 else if (PACK_EXPANSION_P (ot))
5851 return PACK_EXPANSION_P (nt)
5852 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5853 PACK_EXPANSION_PATTERN (nt));
5854 else if (ARGUMENT_PACK_P (ot))
5859 if (!ARGUMENT_PACK_P (nt))
5862 opack = ARGUMENT_PACK_ARGS (ot);
5863 npack = ARGUMENT_PACK_ARGS (nt);
5864 len = TREE_VEC_LENGTH (opack);
5865 if (TREE_VEC_LENGTH (npack) != len)
5867 for (i = 0; i < len; ++i)
5868 if (!template_args_equal (TREE_VEC_ELT (opack, i),
5869 TREE_VEC_ELT (npack, i)))
5873 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
5875 /* We get here probably because we are in the middle of substituting
5876 into the pattern of a pack expansion. In that case the
5877 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
5878 interested in. So we want to use the initial pack argument for
5880 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
5881 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
5882 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
5883 return template_args_equal (ot, nt);
5885 else if (TYPE_P (nt))
5886 return TYPE_P (ot) && same_type_p (ot, nt);
5887 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5890 return cp_tree_equal (ot, nt);
5893 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5894 of template arguments. Returns 0 otherwise. */
5897 comp_template_args (tree oldargs, tree newargs)
5901 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5904 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5906 tree nt = TREE_VEC_ELT (newargs, i);
5907 tree ot = TREE_VEC_ELT (oldargs, i);
5909 if (! template_args_equal (ot, nt))
5916 add_pending_template (tree d)
5918 tree ti = (TYPE_P (d)
5919 ? CLASSTYPE_TEMPLATE_INFO (d)
5920 : DECL_TEMPLATE_INFO (d));
5921 struct pending_template *pt;
5924 if (TI_PENDING_TEMPLATE_FLAG (ti))
5927 /* We are called both from instantiate_decl, where we've already had a
5928 tinst_level pushed, and instantiate_template, where we haven't.
5930 level = !current_tinst_level || current_tinst_level->decl != d;
5933 push_tinst_level (d);
5935 pt = GGC_NEW (struct pending_template);
5937 pt->tinst = current_tinst_level;
5938 if (last_pending_template)
5939 last_pending_template->next = pt;
5941 pending_templates = pt;
5943 last_pending_template = pt;
5945 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5952 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5953 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5954 documentation for TEMPLATE_ID_EXPR. */
5957 lookup_template_function (tree fns, tree arglist)
5961 if (fns == error_mark_node || arglist == error_mark_node)
5962 return error_mark_node;
5964 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5965 gcc_assert (fns && (is_overloaded_fn (fns)
5966 || TREE_CODE (fns) == IDENTIFIER_NODE));
5968 if (BASELINK_P (fns))
5970 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5972 BASELINK_FUNCTIONS (fns),
5977 type = TREE_TYPE (fns);
5978 if (TREE_CODE (fns) == OVERLOAD || !type)
5979 type = unknown_type_node;
5981 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5984 /* Within the scope of a template class S<T>, the name S gets bound
5985 (in build_self_reference) to a TYPE_DECL for the class, not a
5986 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5987 or one of its enclosing classes, and that type is a template,
5988 return the associated TEMPLATE_DECL. Otherwise, the original
5991 Also handle the case when DECL is a TREE_LIST of ambiguous
5992 injected-class-names from different bases. */
5995 maybe_get_template_decl_from_type_decl (tree decl)
5997 if (decl == NULL_TREE)
6000 /* DR 176: A lookup that finds an injected-class-name (10.2
6001 [class.member.lookup]) can result in an ambiguity in certain cases
6002 (for example, if it is found in more than one base class). If all of
6003 the injected-class-names that are found refer to specializations of
6004 the same class template, and if the name is followed by a
6005 template-argument-list, the reference refers to the class template
6006 itself and not a specialization thereof, and is not ambiguous. */
6007 if (TREE_CODE (decl) == TREE_LIST)
6009 tree t, tmpl = NULL_TREE;
6010 for (t = decl; t; t = TREE_CHAIN (t))
6012 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6015 else if (tmpl != elt)
6018 if (tmpl && t == NULL_TREE)
6024 return (decl != NULL_TREE
6025 && DECL_SELF_REFERENCE_P (decl)
6026 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6027 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6030 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6031 parameters, find the desired type.
6033 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6035 IN_DECL, if non-NULL, is the template declaration we are trying to
6038 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6039 the class we are looking up.
6041 Issue error and warning messages under control of COMPLAIN.
6043 If the template class is really a local class in a template
6044 function, then the FUNCTION_CONTEXT is the function in which it is
6047 ??? Note that this function is currently called *twice* for each
6048 template-id: the first time from the parser, while creating the
6049 incomplete type (finish_template_type), and the second type during the
6050 real instantiation (instantiate_template_class). This is surely something
6051 that we want to avoid. It also causes some problems with argument
6052 coercion (see convert_nontype_argument for more information on this). */
6055 lookup_template_class (tree d1,
6060 tsubst_flags_t complain)
6062 tree templ = NULL_TREE, parmlist;
6069 timevar_push (TV_NAME_LOOKUP);
6071 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6073 tree value = innermost_non_namespace_value (d1);
6074 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6079 push_decl_namespace (context);
6080 templ = lookup_name (d1);
6081 templ = maybe_get_template_decl_from_type_decl (templ);
6083 pop_decl_namespace ();
6086 context = DECL_CONTEXT (templ);
6088 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6090 tree type = TREE_TYPE (d1);
6092 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6093 an implicit typename for the second A. Deal with it. */
6094 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6095 type = TREE_TYPE (type);
6097 if (CLASSTYPE_TEMPLATE_INFO (type))
6099 templ = CLASSTYPE_TI_TEMPLATE (type);
6100 d1 = DECL_NAME (templ);
6103 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6104 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6106 templ = TYPE_TI_TEMPLATE (d1);
6107 d1 = DECL_NAME (templ);
6109 else if (TREE_CODE (d1) == TEMPLATE_DECL
6110 && DECL_TEMPLATE_RESULT (d1)
6111 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6114 d1 = DECL_NAME (templ);
6115 context = DECL_CONTEXT (templ);
6118 /* Issue an error message if we didn't find a template. */
6121 if (complain & tf_error)
6122 error ("%qT is not a template", d1);
6123 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6126 if (TREE_CODE (templ) != TEMPLATE_DECL
6127 /* Make sure it's a user visible template, if it was named by
6129 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6130 && !PRIMARY_TEMPLATE_P (templ)))
6132 if (complain & tf_error)
6134 error ("non-template type %qT used as a template", d1);
6136 error ("for template declaration %q+D", in_decl);
6138 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6141 complain &= ~tf_user;
6143 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6145 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6146 template arguments */
6152 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6154 /* Consider an example where a template template parameter declared as
6156 template <class T, class U = std::allocator<T> > class TT
6158 The template parameter level of T and U are one level larger than
6159 of TT. To proper process the default argument of U, say when an
6160 instantiation `TT<int>' is seen, we need to build the full
6161 arguments containing {int} as the innermost level. Outer levels,
6162 available when not appearing as default template argument, can be
6163 obtained from the arguments of the enclosing template.
6165 Suppose that TT is later substituted with std::vector. The above
6166 instantiation is `TT<int, std::allocator<T> >' with TT at
6167 level 1, and T at level 2, while the template arguments at level 1
6168 becomes {std::vector} and the inner level 2 is {int}. */
6170 outer = DECL_CONTEXT (templ);
6172 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6173 else if (current_template_parms)
6174 /* This is an argument of the current template, so we haven't set
6175 DECL_CONTEXT yet. */
6176 outer = current_template_args ();
6179 arglist = add_to_template_args (outer, arglist);
6181 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6183 /*require_all_args=*/true,
6184 /*use_default_args=*/true);
6185 if (arglist2 == error_mark_node
6186 || (!uses_template_parms (arglist2)
6187 && check_instantiated_args (templ, arglist2, complain)))
6188 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6190 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6191 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6195 tree template_type = TREE_TYPE (templ);
6198 tree found = NULL_TREE;
6201 int is_partial_instantiation;
6203 gen_tmpl = most_general_template (templ);
6204 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6205 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6206 arg_depth = TMPL_ARGS_DEPTH (arglist);
6208 if (arg_depth == 1 && parm_depth > 1)
6210 /* We've been given an incomplete set of template arguments.
6213 template <class T> struct S1 {
6214 template <class U> struct S2 {};
6215 template <class U> struct S2<U*> {};
6218 we will be called with an ARGLIST of `U*', but the
6219 TEMPLATE will be `template <class T> template
6220 <class U> struct S1<T>::S2'. We must fill in the missing
6223 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6225 arg_depth = TMPL_ARGS_DEPTH (arglist);
6228 /* Now we should have enough arguments. */
6229 gcc_assert (parm_depth == arg_depth);
6231 /* From here on, we're only interested in the most general
6234 /* Calculate the BOUND_ARGS. These will be the args that are
6235 actually tsubst'd into the definition to create the
6239 /* We have multiple levels of arguments to coerce, at once. */
6241 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6243 tree bound_args = make_tree_vec (parm_depth);
6245 for (i = saved_depth,
6246 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6247 i > 0 && t != NULL_TREE;
6248 --i, t = TREE_CHAIN (t))
6250 tree a = coerce_template_parms (TREE_VALUE (t),
6253 /*require_all_args=*/true,
6254 /*use_default_args=*/true);
6256 /* Don't process further if one of the levels fails. */
6257 if (a == error_mark_node)
6259 /* Restore the ARGLIST to its full size. */
6260 TREE_VEC_LENGTH (arglist) = saved_depth;
6261 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6264 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6266 /* We temporarily reduce the length of the ARGLIST so
6267 that coerce_template_parms will see only the arguments
6268 corresponding to the template parameters it is
6270 TREE_VEC_LENGTH (arglist)--;
6273 /* Restore the ARGLIST to its full size. */
6274 TREE_VEC_LENGTH (arglist) = saved_depth;
6276 arglist = bound_args;
6280 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6281 INNERMOST_TEMPLATE_ARGS (arglist),
6284 /*require_all_args=*/true,
6285 /*use_default_args=*/true);
6287 if (arglist == error_mark_node)
6288 /* We were unable to bind the arguments. */
6289 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6291 /* In the scope of a template class, explicit references to the
6292 template class refer to the type of the template, not any
6293 instantiation of it. For example, in:
6295 template <class T> class C { void f(C<T>); }
6297 the `C<T>' is just the same as `C'. Outside of the
6298 class, however, such a reference is an instantiation. */
6300 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6301 || currently_open_class (template_type))
6302 /* comp_template_args is expensive, check it last. */
6303 && comp_template_args (TYPE_TI_ARGS (template_type),
6305 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6307 /* If we already have this specialization, return it. */
6308 elt.tmpl = gen_tmpl;
6310 hash = hash_specialization (&elt);
6311 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6315 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6317 /* This type is a "partial instantiation" if any of the template
6318 arguments still involve template parameters. Note that we set
6319 IS_PARTIAL_INSTANTIATION for partial specializations as
6321 is_partial_instantiation = uses_template_parms (arglist);
6323 /* If the deduced arguments are invalid, then the binding
6325 if (!is_partial_instantiation
6326 && check_instantiated_args (gen_tmpl,
6327 INNERMOST_TEMPLATE_ARGS (arglist),
6329 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6331 if (!is_partial_instantiation
6332 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6333 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6334 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6336 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6337 DECL_NAME (gen_tmpl),
6338 /*tag_scope=*/ts_global);
6339 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6342 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6345 context = global_namespace;
6347 /* Create the type. */
6348 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6350 if (!is_partial_instantiation)
6352 set_current_access_from_decl (TYPE_NAME (template_type));
6353 t = start_enum (TYPE_IDENTIFIER (template_type),
6354 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6355 arglist, complain, in_decl),
6356 SCOPED_ENUM_P (template_type));
6360 /* We don't want to call start_enum for this type, since
6361 the values for the enumeration constants may involve
6362 template parameters. And, no one should be interested
6363 in the enumeration constants for such a type. */
6364 t = cxx_make_type (ENUMERAL_TYPE);
6365 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6370 t = make_class_type (TREE_CODE (template_type));
6371 CLASSTYPE_DECLARED_CLASS (t)
6372 = CLASSTYPE_DECLARED_CLASS (template_type);
6373 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6374 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6376 /* A local class. Make sure the decl gets registered properly. */
6377 if (context == current_function_decl)
6378 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6380 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6381 /* This instantiation is another name for the primary
6382 template type. Set the TYPE_CANONICAL field
6384 TYPE_CANONICAL (t) = template_type;
6385 else if (any_template_arguments_need_structural_equality_p (arglist))
6386 /* Some of the template arguments require structural
6387 equality testing, so this template class requires
6388 structural equality testing. */
6389 SET_TYPE_STRUCTURAL_EQUALITY (t);
6392 /* If we called start_enum or pushtag above, this information
6393 will already be set up. */
6396 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6398 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6399 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6400 DECL_SOURCE_LOCATION (type_decl)
6401 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6404 type_decl = TYPE_NAME (t);
6406 TREE_PRIVATE (type_decl)
6407 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6408 TREE_PROTECTED (type_decl)
6409 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6410 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6412 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6413 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6416 /* Set up the template information. We have to figure out which
6417 template is the immediate parent if this is a full
6419 if (parm_depth == 1 || is_partial_instantiation
6420 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6421 /* This case is easy; there are no member templates involved. */
6425 /* This is a full instantiation of a member template. Find
6426 the partial instantiation of which this is an instance. */
6428 /* Temporarily reduce by one the number of levels in the ARGLIST
6429 so as to avoid comparing the last set of arguments. */
6430 TREE_VEC_LENGTH (arglist)--;
6431 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6432 TREE_VEC_LENGTH (arglist)++;
6433 found = CLASSTYPE_TI_TEMPLATE (found);
6436 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
6439 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6440 &elt, hash, INSERT);
6441 *slot = GGC_NEW (spec_entry);
6444 /* Note this use of the partial instantiation so we can check it
6445 later in maybe_process_partial_specialization. */
6446 DECL_TEMPLATE_INSTANTIATIONS (templ)
6447 = tree_cons (arglist, t,
6448 DECL_TEMPLATE_INSTANTIATIONS (templ));
6450 if (TREE_CODE (t) == ENUMERAL_TYPE
6451 && !is_partial_instantiation)
6452 /* Now that the type has been registered on the instantiations
6453 list, we set up the enumerators. Because the enumeration
6454 constants may involve the enumeration type itself, we make
6455 sure to register the type first, and then create the
6456 constants. That way, doing tsubst_expr for the enumeration
6457 constants won't result in recursive calls here; we'll find
6458 the instantiation and exit above. */
6459 tsubst_enum (template_type, t, arglist);
6461 if (is_partial_instantiation)
6462 /* If the type makes use of template parameters, the
6463 code that generates debugging information will crash. */
6464 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6466 /* Possibly limit visibility based on template args. */
6467 TREE_PUBLIC (type_decl) = 1;
6468 determine_visibility (type_decl);
6470 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6472 timevar_pop (TV_NAME_LOOKUP);
6479 /* True when we should also visit template parameters that occur in
6480 non-deduced contexts. */
6481 bool include_nondeduced_p;
6482 struct pointer_set_t *visited;
6485 /* Called from for_each_template_parm via walk_tree. */
6488 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6491 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6492 tree_fn_t fn = pfd->fn;
6493 void *data = pfd->data;
6496 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6497 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6498 pfd->include_nondeduced_p))
6499 return error_mark_node;
6501 switch (TREE_CODE (t))
6504 if (TYPE_PTRMEMFUNC_P (t))
6510 if (!TYPE_TEMPLATE_INFO (t))
6512 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6513 fn, data, pfd->visited,
6514 pfd->include_nondeduced_p))
6515 return error_mark_node;
6519 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6520 fn, data, pfd->visited,
6521 pfd->include_nondeduced_p)
6522 || for_each_template_parm (TYPE_MAX_VALUE (t),
6523 fn, data, pfd->visited,
6524 pfd->include_nondeduced_p))
6525 return error_mark_node;
6529 /* Since we're not going to walk subtrees, we have to do this
6531 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6532 pfd->visited, pfd->include_nondeduced_p))
6533 return error_mark_node;
6537 /* Check the return type. */
6538 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6539 pfd->include_nondeduced_p))
6540 return error_mark_node;
6542 /* Check the parameter types. Since default arguments are not
6543 instantiated until they are needed, the TYPE_ARG_TYPES may
6544 contain expressions that involve template parameters. But,
6545 no-one should be looking at them yet. And, once they're
6546 instantiated, they don't contain template parameters, so
6547 there's no point in looking at them then, either. */
6551 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6552 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6553 pfd->visited, pfd->include_nondeduced_p))
6554 return error_mark_node;
6556 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6557 want walk_tree walking into them itself. */
6563 if (pfd->include_nondeduced_p
6564 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6566 pfd->include_nondeduced_p))
6567 return error_mark_node;
6572 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6573 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6574 pfd->visited, pfd->include_nondeduced_p))
6575 return error_mark_node;
6580 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6581 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6582 pfd->visited, pfd->include_nondeduced_p))
6583 return error_mark_node;
6584 if (DECL_CONTEXT (t)
6585 && pfd->include_nondeduced_p
6586 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6587 pfd->visited, pfd->include_nondeduced_p))
6588 return error_mark_node;
6591 case BOUND_TEMPLATE_TEMPLATE_PARM:
6592 /* Record template parameters such as `T' inside `TT<T>'. */
6593 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6594 pfd->include_nondeduced_p))
6595 return error_mark_node;
6598 case TEMPLATE_TEMPLATE_PARM:
6599 case TEMPLATE_TYPE_PARM:
6600 case TEMPLATE_PARM_INDEX:
6601 if (fn && (*fn)(t, data))
6602 return error_mark_node;
6604 return error_mark_node;
6608 /* A template template parameter is encountered. */
6609 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6610 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6611 pfd->include_nondeduced_p))
6612 return error_mark_node;
6614 /* Already substituted template template parameter */
6620 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6622 pfd->include_nondeduced_p))
6623 return error_mark_node;
6627 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6628 && pfd->include_nondeduced_p
6629 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6630 (TREE_TYPE (t)), fn, data,
6631 pfd->visited, pfd->include_nondeduced_p))
6632 return error_mark_node;
6637 /* If there's no type, then this thing must be some expression
6638 involving template parameters. */
6639 if (!fn && !TREE_TYPE (t))
6640 return error_mark_node;
6645 case REINTERPRET_CAST_EXPR:
6646 case CONST_CAST_EXPR:
6647 case STATIC_CAST_EXPR:
6648 case DYNAMIC_CAST_EXPR:
6652 case PSEUDO_DTOR_EXPR:
6654 return error_mark_node;
6661 /* We didn't find any template parameters we liked. */
6665 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6666 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6667 call FN with the parameter and the DATA.
6668 If FN returns nonzero, the iteration is terminated, and
6669 for_each_template_parm returns 1. Otherwise, the iteration
6670 continues. If FN never returns a nonzero value, the value
6671 returned by for_each_template_parm is 0. If FN is NULL, it is
6672 considered to be the function which always returns 1.
6674 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6675 parameters that occur in non-deduced contexts. When false, only
6676 visits those template parameters that can be deduced. */
6679 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6680 struct pointer_set_t *visited,
6681 bool include_nondeduced_p)
6683 struct pair_fn_data pfd;
6689 pfd.include_nondeduced_p = include_nondeduced_p;
6691 /* Walk the tree. (Conceptually, we would like to walk without
6692 duplicates, but for_each_template_parm_r recursively calls
6693 for_each_template_parm, so we would need to reorganize a fair
6694 bit to use walk_tree_without_duplicates, so we keep our own
6697 pfd.visited = visited;
6699 pfd.visited = pointer_set_create ();
6700 result = cp_walk_tree (&t,
6701 for_each_template_parm_r,
6703 pfd.visited) != NULL_TREE;
6708 pointer_set_destroy (pfd.visited);
6715 /* Returns true if T depends on any template parameter. */
6718 uses_template_parms (tree t)
6721 int saved_processing_template_decl;
6723 saved_processing_template_decl = processing_template_decl;
6724 if (!saved_processing_template_decl)
6725 processing_template_decl = 1;
6727 dependent_p = dependent_type_p (t);
6728 else if (TREE_CODE (t) == TREE_VEC)
6729 dependent_p = any_dependent_template_arguments_p (t);
6730 else if (TREE_CODE (t) == TREE_LIST)
6731 dependent_p = (uses_template_parms (TREE_VALUE (t))
6732 || uses_template_parms (TREE_CHAIN (t)));
6733 else if (TREE_CODE (t) == TYPE_DECL)
6734 dependent_p = dependent_type_p (TREE_TYPE (t));
6737 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6738 || TREE_CODE (t) == OVERLOAD
6739 || TREE_CODE (t) == BASELINK
6740 || TREE_CODE (t) == IDENTIFIER_NODE
6741 || TREE_CODE (t) == TRAIT_EXPR
6742 || TREE_CODE (t) == CONSTRUCTOR
6743 || CONSTANT_CLASS_P (t))
6744 dependent_p = (type_dependent_expression_p (t)
6745 || value_dependent_expression_p (t));
6748 gcc_assert (t == error_mark_node);
6749 dependent_p = false;
6752 processing_template_decl = saved_processing_template_decl;
6757 /* Returns true if T depends on any template parameter with level LEVEL. */
6760 uses_template_parms_level (tree t, int level)
6762 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6763 /*include_nondeduced_p=*/true);
6766 static int tinst_depth;
6767 extern int max_tinst_depth;
6768 #ifdef GATHER_STATISTICS
6771 static int tinst_level_tick;
6772 static int last_template_error_tick;
6774 /* We're starting to instantiate D; record the template instantiation context
6775 for diagnostics and to restore it later. */
6778 push_tinst_level (tree d)
6780 struct tinst_level *new_level;
6782 if (tinst_depth >= max_tinst_depth)
6784 /* If the instantiation in question still has unbound template parms,
6785 we don't really care if we can't instantiate it, so just return.
6786 This happens with base instantiation for implicit `typename'. */
6787 if (uses_template_parms (d))
6790 last_template_error_tick = tinst_level_tick;
6791 error ("template instantiation depth exceeds maximum of %d (use "
6792 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6793 max_tinst_depth, d);
6795 print_instantiation_context ();
6800 new_level = GGC_NEW (struct tinst_level);
6801 new_level->decl = d;
6802 new_level->locus = input_location;
6803 new_level->in_system_header_p = in_system_header;
6804 new_level->next = current_tinst_level;
6805 current_tinst_level = new_level;
6808 #ifdef GATHER_STATISTICS
6809 if (tinst_depth > depth_reached)
6810 depth_reached = tinst_depth;
6817 /* We're done instantiating this template; return to the instantiation
6821 pop_tinst_level (void)
6823 /* Restore the filename and line number stashed away when we started
6824 this instantiation. */
6825 input_location = current_tinst_level->locus;
6826 current_tinst_level = current_tinst_level->next;
6831 /* We're instantiating a deferred template; restore the template
6832 instantiation context in which the instantiation was requested, which
6833 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6836 reopen_tinst_level (struct tinst_level *level)
6838 struct tinst_level *t;
6841 for (t = level; t; t = t->next)
6844 current_tinst_level = level;
6849 /* Returns the TINST_LEVEL which gives the original instantiation
6852 struct tinst_level *
6853 outermost_tinst_level (void)
6855 struct tinst_level *level = current_tinst_level;
6858 level = level->next;
6862 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
6865 parameter_of_template_p (tree parm, tree templ)
6870 if (!parm || !templ)
6873 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
6874 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6876 parms = DECL_TEMPLATE_PARMS (templ);
6877 parms = INNERMOST_TEMPLATE_PARMS (parms);
6879 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
6880 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
6886 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6887 vector of template arguments, as for tsubst.
6889 Returns an appropriate tsubst'd friend declaration. */
6892 tsubst_friend_function (tree decl, tree args)
6896 if (TREE_CODE (decl) == FUNCTION_DECL
6897 && DECL_TEMPLATE_INSTANTIATION (decl)
6898 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6899 /* This was a friend declared with an explicit template
6900 argument list, e.g.:
6904 to indicate that f was a template instantiation, not a new
6905 function declaration. Now, we have to figure out what
6906 instantiation of what template. */
6908 tree template_id, arglist, fns;
6911 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6913 /* Friend functions are looked up in the containing namespace scope.
6914 We must enter that scope, to avoid finding member functions of the
6915 current class with same name. */
6916 push_nested_namespace (ns);
6917 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6918 tf_warning_or_error, NULL_TREE,
6919 /*integral_constant_expression_p=*/false);
6920 pop_nested_namespace (ns);
6921 arglist = tsubst (DECL_TI_ARGS (decl), args,
6922 tf_warning_or_error, NULL_TREE);
6923 template_id = lookup_template_function (fns, arglist);
6925 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6926 tmpl = determine_specialization (template_id, new_friend,
6928 /*need_member_template=*/0,
6929 TREE_VEC_LENGTH (args),
6931 return instantiate_template (tmpl, new_args, tf_error);
6934 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6936 /* The NEW_FRIEND will look like an instantiation, to the
6937 compiler, but is not an instantiation from the point of view of
6938 the language. For example, we might have had:
6940 template <class T> struct S {
6941 template <class U> friend void f(T, U);
6944 Then, in S<int>, template <class U> void f(int, U) is not an
6945 instantiation of anything. */
6946 if (new_friend == error_mark_node)
6947 return error_mark_node;
6949 DECL_USE_TEMPLATE (new_friend) = 0;
6950 if (TREE_CODE (decl) == TEMPLATE_DECL)
6952 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6953 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6954 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6957 /* The mangled name for the NEW_FRIEND is incorrect. The function
6958 is not a template instantiation and should not be mangled like
6959 one. Therefore, we forget the mangling here; we'll recompute it
6960 later if we need it. */
6961 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6963 SET_DECL_RTL (new_friend, NULL_RTX);
6964 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6967 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6970 tree new_friend_template_info;
6971 tree new_friend_result_template_info;
6973 int new_friend_is_defn;
6975 /* We must save some information from NEW_FRIEND before calling
6976 duplicate decls since that function will free NEW_FRIEND if
6978 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6979 new_friend_is_defn =
6980 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6981 (template_for_substitution (new_friend)))
6983 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6985 /* This declaration is a `primary' template. */
6986 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6988 new_friend_result_template_info
6989 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6992 new_friend_result_template_info = NULL_TREE;
6994 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6995 if (new_friend_is_defn)
6996 DECL_INITIAL (new_friend) = error_mark_node;
6998 /* Inside pushdecl_namespace_level, we will push into the
6999 current namespace. However, the friend function should go
7000 into the namespace of the template. */
7001 ns = decl_namespace_context (new_friend);
7002 push_nested_namespace (ns);
7003 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7004 pop_nested_namespace (ns);
7006 if (old_decl == error_mark_node)
7007 return error_mark_node;
7009 if (old_decl != new_friend)
7011 /* This new friend declaration matched an existing
7012 declaration. For example, given:
7014 template <class T> void f(T);
7015 template <class U> class C {
7016 template <class T> friend void f(T) {}
7019 the friend declaration actually provides the definition
7020 of `f', once C has been instantiated for some type. So,
7021 old_decl will be the out-of-class template declaration,
7022 while new_friend is the in-class definition.
7024 But, if `f' was called before this point, the
7025 instantiation of `f' will have DECL_TI_ARGS corresponding
7026 to `T' but not to `U', references to which might appear
7027 in the definition of `f'. Previously, the most general
7028 template for an instantiation of `f' was the out-of-class
7029 version; now it is the in-class version. Therefore, we
7030 run through all specialization of `f', adding to their
7031 DECL_TI_ARGS appropriately. In particular, they need a
7032 new set of outer arguments, corresponding to the
7033 arguments for this class instantiation.
7035 The same situation can arise with something like this:
7038 template <class T> class C {
7042 when `C<int>' is instantiated. Now, `f(int)' is defined
7045 if (!new_friend_is_defn)
7046 /* On the other hand, if the in-class declaration does
7047 *not* provide a definition, then we don't want to alter
7048 existing definitions. We can just leave everything
7053 tree new_template = TI_TEMPLATE (new_friend_template_info);
7054 tree new_args = TI_ARGS (new_friend_template_info);
7056 /* Overwrite whatever template info was there before, if
7057 any, with the new template information pertaining to
7059 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7061 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7062 /* We should have called reregister_specialization in
7064 gcc_assert (retrieve_specialization (new_template,
7071 /* Indicate that the old function template is a partial
7073 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7074 = new_friend_result_template_info;
7076 gcc_assert (new_template
7077 == most_general_template (new_template));
7078 gcc_assert (new_template != old_decl);
7080 /* Reassign any specializations already in the hash table
7081 to the new more general template, and add the
7082 additional template args. */
7083 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7087 tree spec = TREE_VALUE (t);
7090 elt.tmpl = old_decl;
7091 elt.args = DECL_TI_ARGS (spec);
7092 elt.spec = NULL_TREE;
7094 htab_remove_elt (decl_specializations, &elt);
7097 = add_outermost_template_args (new_args,
7098 DECL_TI_ARGS (spec));
7100 register_specialization
7101 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7104 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7108 /* The information from NEW_FRIEND has been merged into OLD_DECL
7109 by duplicate_decls. */
7110 new_friend = old_decl;
7115 tree context = DECL_CONTEXT (new_friend);
7119 template <class T> class C {
7120 template <class U> friend void C1<U>::f (); // case 1
7121 friend void C2<T>::f (); // case 2
7123 we only need to make sure CONTEXT is a complete type for
7124 case 2. To distinguish between the two cases, we note that
7125 CONTEXT of case 1 remains dependent type after tsubst while
7126 this isn't true for case 2. */
7127 ++processing_template_decl;
7128 dependent_p = dependent_type_p (context);
7129 --processing_template_decl;
7132 && !complete_type_or_else (context, NULL_TREE))
7133 return error_mark_node;
7135 if (COMPLETE_TYPE_P (context))
7137 /* Check to see that the declaration is really present, and,
7138 possibly obtain an improved declaration. */
7139 tree fn = check_classfn (context,
7140 new_friend, NULL_TREE);
7150 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7151 template arguments, as for tsubst.
7153 Returns an appropriate tsubst'd friend type or error_mark_node on
7157 tsubst_friend_class (tree friend_tmpl, tree args)
7163 context = DECL_CONTEXT (friend_tmpl);
7167 if (TREE_CODE (context) == NAMESPACE_DECL)
7168 push_nested_namespace (context);
7170 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7173 /* Look for a class template declaration. We look for hidden names
7174 because two friend declarations of the same template are the
7175 same. For example, in:
7178 template <typename> friend class F;
7180 template <typename> struct B {
7181 template <typename> friend class F;
7184 both F templates are the same. */
7185 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7186 /*block_p=*/true, 0,
7187 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7189 /* But, if we don't find one, it might be because we're in a
7190 situation like this:
7198 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7199 for `S<int>', not the TEMPLATE_DECL. */
7200 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7202 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7203 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7206 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7208 /* The friend template has already been declared. Just
7209 check to see that the declarations match, and install any new
7210 default parameters. We must tsubst the default parameters,
7211 of course. We only need the innermost template parameters
7212 because that is all that redeclare_class_template will look
7214 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7215 > TMPL_ARGS_DEPTH (args))
7218 location_t saved_input_location;
7219 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7220 args, tf_warning_or_error);
7222 saved_input_location = input_location;
7223 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7224 redeclare_class_template (TREE_TYPE (tmpl), parms);
7225 input_location = saved_input_location;
7229 friend_type = TREE_TYPE (tmpl);
7233 /* The friend template has not already been declared. In this
7234 case, the instantiation of the template class will cause the
7235 injection of this template into the global scope. */
7236 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7237 if (tmpl == error_mark_node)
7238 return error_mark_node;
7240 /* The new TMPL is not an instantiation of anything, so we
7241 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7242 the new type because that is supposed to be the corresponding
7243 template decl, i.e., TMPL. */
7244 DECL_USE_TEMPLATE (tmpl) = 0;
7245 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7246 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7247 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7248 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7250 /* Inject this template into the global scope. */
7251 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7256 if (TREE_CODE (context) == NAMESPACE_DECL)
7257 pop_nested_namespace (context);
7259 pop_nested_class ();
7265 /* Returns zero if TYPE cannot be completed later due to circularity.
7266 Otherwise returns one. */
7269 can_complete_type_without_circularity (tree type)
7271 if (type == NULL_TREE || type == error_mark_node)
7273 else if (COMPLETE_TYPE_P (type))
7275 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7276 return can_complete_type_without_circularity (TREE_TYPE (type));
7277 else if (CLASS_TYPE_P (type)
7278 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7284 /* Apply any attributes which had to be deferred until instantiation
7285 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7286 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7289 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7290 tree args, tsubst_flags_t complain, tree in_decl)
7292 tree last_dep = NULL_TREE;
7296 for (t = attributes; t; t = TREE_CHAIN (t))
7297 if (ATTR_IS_DEPENDENT (t))
7300 attributes = copy_list (attributes);
7304 if (DECL_P (*decl_p))
7306 if (TREE_TYPE (*decl_p) == error_mark_node)
7308 p = &DECL_ATTRIBUTES (*decl_p);
7311 p = &TYPE_ATTRIBUTES (*decl_p);
7315 tree late_attrs = NULL_TREE;
7316 tree *q = &late_attrs;
7318 for (*p = attributes; *p; )
7321 if (ATTR_IS_DEPENDENT (t))
7323 *p = TREE_CHAIN (t);
7324 TREE_CHAIN (t) = NULL_TREE;
7325 /* If the first attribute argument is an identifier, don't
7326 pass it through tsubst. Attributes like mode, format,
7327 cleanup and several target specific attributes expect it
7330 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7331 && TREE_VALUE (TREE_VALUE (t))
7332 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7333 == IDENTIFIER_NODE))
7336 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7338 /*integral_constant_expression_p=*/false);
7339 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7341 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7346 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7347 /*integral_constant_expression_p=*/false);
7349 q = &TREE_CHAIN (t);
7352 p = &TREE_CHAIN (t);
7355 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7359 /* Perform (or defer) access check for typedefs that were referenced
7360 from within the template TMPL code.
7361 This is a subroutine of instantiate_template and instantiate_class_template.
7362 TMPL is the template to consider and TARGS is the list of arguments of
7366 perform_typedefs_access_check (tree tmpl, tree targs)
7371 || (!CLASS_TYPE_P (tmpl)
7372 && TREE_CODE (tmpl) != FUNCTION_DECL))
7375 for (t = get_types_needing_access_check (tmpl); t; t = TREE_CHAIN (t))
7377 tree type_decl = TREE_PURPOSE (t);
7378 tree type_scope = TREE_VALUE (t);
7380 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7383 if (uses_template_parms (type_decl))
7384 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7385 if (uses_template_parms (type_scope))
7386 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7388 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7389 type_decl, type_decl);
7394 instantiate_class_template (tree type)
7396 tree templ, args, pattern, t, member;
7400 unsigned int saved_maximum_field_alignment;
7402 if (type == error_mark_node)
7403 return error_mark_node;
7405 if (TYPE_BEING_DEFINED (type)
7406 || COMPLETE_TYPE_P (type)
7407 || uses_template_parms (type))
7410 /* Figure out which template is being instantiated. */
7411 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7412 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7414 /* Determine what specialization of the original template to
7416 t = most_specialized_class (type, templ);
7417 if (t == error_mark_node)
7419 TYPE_BEING_DEFINED (type) = 1;
7420 return error_mark_node;
7424 /* This TYPE is actually an instantiation of a partial
7425 specialization. We replace the innermost set of ARGS with
7426 the arguments appropriate for substitution. For example,
7429 template <class T> struct S {};
7430 template <class T> struct S<T*> {};
7432 and supposing that we are instantiating S<int*>, ARGS will
7433 presently be {int*} -- but we need {int}. */
7434 pattern = TREE_TYPE (t);
7435 args = TREE_PURPOSE (t);
7439 pattern = TREE_TYPE (templ);
7440 args = CLASSTYPE_TI_ARGS (type);
7443 /* If the template we're instantiating is incomplete, then clearly
7444 there's nothing we can do. */
7445 if (!COMPLETE_TYPE_P (pattern))
7448 /* If we've recursively instantiated too many templates, stop. */
7449 if (! push_tinst_level (type))
7452 /* Now we're really doing the instantiation. Mark the type as in
7453 the process of being defined. */
7454 TYPE_BEING_DEFINED (type) = 1;
7456 /* We may be in the middle of deferred access check. Disable
7458 push_deferring_access_checks (dk_no_deferred);
7460 push_to_top_level ();
7461 /* Use #pragma pack from the template context. */
7462 saved_maximum_field_alignment = maximum_field_alignment;
7463 maximum_field_alignment = TYPE_PRECISION (pattern);
7465 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7467 /* Set the input location to the most specialized template definition.
7468 This is needed if tsubsting causes an error. */
7469 typedecl = TYPE_MAIN_DECL (pattern);
7470 input_location = DECL_SOURCE_LOCATION (typedecl);
7472 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7473 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7474 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7475 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7476 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7477 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7478 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7479 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7480 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7481 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7482 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7483 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7484 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7485 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7486 if (ANON_AGGR_TYPE_P (pattern))
7487 SET_ANON_AGGR_TYPE_P (type);
7488 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7490 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7491 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7494 pbinfo = TYPE_BINFO (pattern);
7496 /* We should never instantiate a nested class before its enclosing
7497 class; we need to look up the nested class by name before we can
7498 instantiate it, and that lookup should instantiate the enclosing
7500 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7501 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7502 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7504 base_list = NULL_TREE;
7505 if (BINFO_N_BASE_BINFOS (pbinfo))
7508 tree context = TYPE_CONTEXT (type);
7512 /* We must enter the scope containing the type, as that is where
7513 the accessibility of types named in dependent bases are
7515 pushed_scope = push_scope (context ? context : global_namespace);
7517 /* Substitute into each of the bases to determine the actual
7519 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7522 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7523 tree expanded_bases = NULL_TREE;
7526 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7529 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7530 args, tf_error, NULL_TREE);
7531 if (expanded_bases == error_mark_node)
7534 len = TREE_VEC_LENGTH (expanded_bases);
7537 for (idx = 0; idx < len; idx++)
7540 /* Extract the already-expanded base class. */
7541 base = TREE_VEC_ELT (expanded_bases, idx);
7543 /* Substitute to figure out the base class. */
7544 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7547 if (base == error_mark_node)
7550 base_list = tree_cons (access, base, base_list);
7551 if (BINFO_VIRTUAL_P (pbase_binfo))
7552 TREE_TYPE (base_list) = integer_type_node;
7556 /* The list is now in reverse order; correct that. */
7557 base_list = nreverse (base_list);
7560 pop_scope (pushed_scope);
7562 /* Now call xref_basetypes to set up all the base-class
7564 xref_basetypes (type, base_list);
7566 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7567 (int) ATTR_FLAG_TYPE_IN_PLACE,
7568 args, tf_error, NULL_TREE);
7570 /* Now that our base classes are set up, enter the scope of the
7571 class, so that name lookups into base classes, etc. will work
7572 correctly. This is precisely analogous to what we do in
7573 begin_class_definition when defining an ordinary non-template
7574 class, except we also need to push the enclosing classes. */
7575 push_nested_class (type);
7577 /* Now members are processed in the order of declaration. */
7578 for (member = CLASSTYPE_DECL_LIST (pattern);
7579 member; member = TREE_CHAIN (member))
7581 tree t = TREE_VALUE (member);
7583 if (TREE_PURPOSE (member))
7587 /* Build new CLASSTYPE_NESTED_UTDS. */
7590 bool class_template_p;
7592 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7593 && TYPE_LANG_SPECIFIC (t)
7594 && CLASSTYPE_IS_TEMPLATE (t));
7595 /* If the member is a class template, then -- even after
7596 substitution -- there may be dependent types in the
7597 template argument list for the class. We increment
7598 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7599 that function will assume that no types are dependent
7600 when outside of a template. */
7601 if (class_template_p)
7602 ++processing_template_decl;
7603 newtag = tsubst (t, args, tf_error, NULL_TREE);
7604 if (class_template_p)
7605 --processing_template_decl;
7606 if (newtag == error_mark_node)
7609 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7611 tree name = TYPE_IDENTIFIER (t);
7613 if (class_template_p)
7614 /* Unfortunately, lookup_template_class sets
7615 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7616 instantiation (i.e., for the type of a member
7617 template class nested within a template class.)
7618 This behavior is required for
7619 maybe_process_partial_specialization to work
7620 correctly, but is not accurate in this case;
7621 the TAG is not an instantiation of anything.
7622 (The corresponding TEMPLATE_DECL is an
7623 instantiation, but the TYPE is not.) */
7624 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7626 /* Now, we call pushtag to put this NEWTAG into the scope of
7627 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7628 pushtag calling push_template_decl. We don't have to do
7629 this for enums because it will already have been done in
7632 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7633 pushtag (name, newtag, /*tag_scope=*/ts_current);
7636 else if (TREE_CODE (t) == FUNCTION_DECL
7637 || DECL_FUNCTION_TEMPLATE_P (t))
7639 /* Build new TYPE_METHODS. */
7642 if (TREE_CODE (t) == TEMPLATE_DECL)
7643 ++processing_template_decl;
7644 r = tsubst (t, args, tf_error, NULL_TREE);
7645 if (TREE_CODE (t) == TEMPLATE_DECL)
7646 --processing_template_decl;
7647 set_current_access_from_decl (r);
7648 finish_member_declaration (r);
7652 /* Build new TYPE_FIELDS. */
7653 if (TREE_CODE (t) == STATIC_ASSERT)
7656 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7657 tf_warning_or_error, NULL_TREE,
7658 /*integral_constant_expression_p=*/true);
7659 finish_static_assert (condition,
7660 STATIC_ASSERT_MESSAGE (t),
7661 STATIC_ASSERT_SOURCE_LOCATION (t),
7664 else if (TREE_CODE (t) != CONST_DECL)
7668 /* The file and line for this declaration, to
7669 assist in error message reporting. Since we
7670 called push_tinst_level above, we don't need to
7672 input_location = DECL_SOURCE_LOCATION (t);
7674 if (TREE_CODE (t) == TEMPLATE_DECL)
7675 ++processing_template_decl;
7676 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7677 if (TREE_CODE (t) == TEMPLATE_DECL)
7678 --processing_template_decl;
7679 if (TREE_CODE (r) == VAR_DECL)
7683 [t]he initialization (and any associated
7684 side-effects) of a static data member does
7685 not occur unless the static data member is
7686 itself used in a way that requires the
7687 definition of the static data member to
7690 Therefore, we do not substitute into the
7691 initialized for the static data member here. */
7692 finish_static_data_member_decl
7695 /*init_const_expr_p=*/false,
7696 /*asmspec_tree=*/NULL_TREE,
7698 if (DECL_INITIALIZED_IN_CLASS_P (r))
7699 check_static_variable_definition (r, TREE_TYPE (r));
7701 else if (TREE_CODE (r) == FIELD_DECL)
7703 /* Determine whether R has a valid type and can be
7704 completed later. If R is invalid, then it is
7705 replaced by error_mark_node so that it will not be
7706 added to TYPE_FIELDS. */
7707 tree rtype = TREE_TYPE (r);
7708 if (can_complete_type_without_circularity (rtype))
7709 complete_type (rtype);
7711 if (!COMPLETE_TYPE_P (rtype))
7713 cxx_incomplete_type_error (r, rtype);
7714 r = error_mark_node;
7718 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7719 such a thing will already have been added to the field
7720 list by tsubst_enum in finish_member_declaration in the
7721 CLASSTYPE_NESTED_UTDS case above. */
7722 if (!(TREE_CODE (r) == TYPE_DECL
7723 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7724 && DECL_ARTIFICIAL (r)))
7726 set_current_access_from_decl (r);
7727 finish_member_declaration (r);
7734 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7736 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7738 tree friend_type = t;
7739 bool adjust_processing_template_decl = false;
7741 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7743 /* template <class T> friend class C; */
7744 friend_type = tsubst_friend_class (friend_type, args);
7745 adjust_processing_template_decl = true;
7747 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7749 /* template <class T> friend class C::D; */
7750 friend_type = tsubst (friend_type, args,
7751 tf_warning_or_error, NULL_TREE);
7752 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7753 friend_type = TREE_TYPE (friend_type);
7754 adjust_processing_template_decl = true;
7756 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7758 /* This could be either
7762 when dependent_type_p is false or
7764 template <class U> friend class T::C;
7767 friend_type = tsubst (friend_type, args,
7768 tf_warning_or_error, NULL_TREE);
7769 /* Bump processing_template_decl for correct
7770 dependent_type_p calculation. */
7771 ++processing_template_decl;
7772 if (dependent_type_p (friend_type))
7773 adjust_processing_template_decl = true;
7774 --processing_template_decl;
7776 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7777 && hidden_name_p (TYPE_NAME (friend_type)))
7781 where C hasn't been declared yet. Let's lookup name
7782 from namespace scope directly, bypassing any name that
7783 come from dependent base class. */
7784 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7786 /* The call to xref_tag_from_type does injection for friend
7788 push_nested_namespace (ns);
7790 xref_tag_from_type (friend_type, NULL_TREE,
7791 /*tag_scope=*/ts_current);
7792 pop_nested_namespace (ns);
7794 else if (uses_template_parms (friend_type))
7795 /* friend class C<T>; */
7796 friend_type = tsubst (friend_type, args,
7797 tf_warning_or_error, NULL_TREE);
7802 where C is already declared or
7804 friend class C<int>;
7806 We don't have to do anything in these cases. */
7808 if (adjust_processing_template_decl)
7809 /* Trick make_friend_class into realizing that the friend
7810 we're adding is a template, not an ordinary class. It's
7811 important that we use make_friend_class since it will
7812 perform some error-checking and output cross-reference
7814 ++processing_template_decl;
7816 if (friend_type != error_mark_node)
7817 make_friend_class (type, friend_type, /*complain=*/false);
7819 if (adjust_processing_template_decl)
7820 --processing_template_decl;
7824 /* Build new DECL_FRIENDLIST. */
7827 /* The file and line for this declaration, to
7828 assist in error message reporting. Since we
7829 called push_tinst_level above, we don't need to
7831 input_location = DECL_SOURCE_LOCATION (t);
7833 if (TREE_CODE (t) == TEMPLATE_DECL)
7835 ++processing_template_decl;
7836 push_deferring_access_checks (dk_no_check);
7839 r = tsubst_friend_function (t, args);
7840 add_friend (type, r, /*complain=*/false);
7841 if (TREE_CODE (t) == TEMPLATE_DECL)
7843 pop_deferring_access_checks ();
7844 --processing_template_decl;
7850 /* Set the file and line number information to whatever is given for
7851 the class itself. This puts error messages involving generated
7852 implicit functions at a predictable point, and the same point
7853 that would be used for non-template classes. */
7854 input_location = DECL_SOURCE_LOCATION (typedecl);
7856 unreverse_member_declarations (type);
7857 finish_struct_1 (type);
7858 TYPE_BEING_DEFINED (type) = 0;
7860 /* Now that the class is complete, instantiate default arguments for
7861 any member functions. We don't do this earlier because the
7862 default arguments may reference members of the class. */
7863 if (!PRIMARY_TEMPLATE_P (templ))
7864 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7865 if (TREE_CODE (t) == FUNCTION_DECL
7866 /* Implicitly generated member functions will not have template
7867 information; they are not instantiations, but instead are
7868 created "fresh" for each instantiation. */
7869 && DECL_TEMPLATE_INFO (t))
7870 tsubst_default_arguments (t);
7872 /* Some typedefs referenced from within the template code need to be access
7873 checked at template instantiation time, i.e now. These types were
7874 added to the template at parsing time. Let's get those and perform
7875 the access checks then. */
7876 perform_typedefs_access_check (pattern, args);
7877 perform_deferred_access_checks ();
7878 pop_nested_class ();
7879 maximum_field_alignment = saved_maximum_field_alignment;
7880 pop_from_top_level ();
7881 pop_deferring_access_checks ();
7884 /* The vtable for a template class can be emitted in any translation
7885 unit in which the class is instantiated. When there is no key
7886 method, however, finish_struct_1 will already have added TYPE to
7887 the keyed_classes list. */
7888 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7889 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7895 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7901 else if (TYPE_P (t))
7902 r = tsubst (t, args, complain, in_decl);
7905 r = tsubst_expr (t, args, complain, in_decl,
7906 /*integral_constant_expression_p=*/true);
7907 r = fold_non_dependent_expr (r);
7912 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
7913 NONTYPE_ARGUMENT_PACK. */
7916 make_fnparm_pack (tree spec_parm)
7918 /* Collect all of the extra "packed" parameters into an
7922 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
7923 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
7924 int i, len = list_length (spec_parm);
7926 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
7927 parmvec = make_tree_vec (len);
7928 parmtypevec = make_tree_vec (len);
7929 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
7931 TREE_VEC_ELT (parmvec, i) = spec_parm;
7932 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
7935 /* Build the argument packs. */
7936 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
7937 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
7938 TREE_TYPE (argpack) = argtypepack;
7943 /* Substitute ARGS into T, which is an pack expansion
7944 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7945 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7946 (if only a partial substitution could be performed) or
7947 ERROR_MARK_NODE if there was an error. */
7949 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7953 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7954 tree first_arg_pack; int i, len = -1;
7957 bool very_local_specializations = false;
7959 gcc_assert (PACK_EXPANSION_P (t));
7960 pattern = PACK_EXPANSION_PATTERN (t);
7962 /* Determine the argument packs that will instantiate the parameter
7963 packs used in the expansion expression. While we're at it,
7964 compute the number of arguments to be expanded and make sure it
7966 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7967 pack = TREE_CHAIN (pack))
7969 tree parm_pack = TREE_VALUE (pack);
7970 tree arg_pack = NULL_TREE;
7971 tree orig_arg = NULL_TREE;
7973 if (TREE_CODE (parm_pack) == PARM_DECL)
7975 arg_pack = retrieve_local_specialization (parm_pack);
7976 if (arg_pack == NULL_TREE)
7978 /* This can happen for a parameter name used later in a function
7979 declaration (such as in a late-specified return type). Just
7980 make a dummy decl, since it's only used for its type. */
7981 gcc_assert (cp_unevaluated_operand != 0);
7982 arg_pack = tsubst_decl (parm_pack, args, complain);
7983 arg_pack = make_fnparm_pack (arg_pack);
7988 int level, idx, levels;
7989 template_parm_level_and_index (parm_pack, &level, &idx);
7991 levels = TMPL_ARGS_DEPTH (args);
7992 if (level <= levels)
7993 arg_pack = TMPL_ARG (args, level, idx);
7996 orig_arg = arg_pack;
7997 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7998 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8000 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8001 /* This can only happen if we forget to expand an argument
8002 pack somewhere else. Just return an error, silently. */
8004 result = make_tree_vec (1);
8005 TREE_VEC_ELT (result, 0) = error_mark_node;
8010 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8011 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8013 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8014 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8015 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
8016 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
8017 /* The argument pack that the parameter maps to is just an
8018 expansion of the parameter itself, such as one would
8019 find in the implicit typedef of a class inside the
8020 class itself. Consider this parameter "unsubstituted",
8021 so that we will maintain the outer pack expansion. */
8022 arg_pack = NULL_TREE;
8028 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8030 /* It's all-or-nothing with incomplete argument packs. */
8031 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8032 return error_mark_node;
8034 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8040 first_arg_pack = arg_pack;
8042 else if (len != my_len)
8045 /* We got explicit args for some packs but not others;
8046 do nothing now and try again after deduction. */
8048 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8049 error ("mismatched argument pack lengths while expanding "
8053 error ("mismatched argument pack lengths while expanding "
8056 return error_mark_node;
8059 /* Keep track of the parameter packs and their corresponding
8061 packs = tree_cons (parm_pack, arg_pack, packs);
8062 TREE_TYPE (packs) = orig_arg;
8065 /* We can't substitute for this parameter pack. */
8066 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8068 unsubstituted_packs);
8071 /* We cannot expand this expansion expression, because we don't have
8072 all of the argument packs we need. Substitute into the pattern
8073 and return a PACK_EXPANSION_*. The caller will need to deal with
8075 if (unsubstituted_packs)
8078 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8079 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8080 /*integral_constant_expression_p=*/false);
8082 new_pat = tsubst (pattern, args, complain, in_decl);
8083 return make_pack_expansion (new_pat);
8086 /* We could not find any argument packs that work. */
8088 return error_mark_node;
8090 if (!local_specializations)
8092 /* We're in a late-specified return type, so we don't have a local
8093 specializations table. Create one for doing this expansion. */
8094 very_local_specializations = true;
8095 local_specializations = htab_create (37,
8096 hash_local_specialization,
8097 eq_local_specializations,
8101 /* For each argument in each argument pack, substitute into the
8103 result = make_tree_vec (len + incomplete);
8104 for (i = 0; i < len + incomplete; ++i)
8106 /* For parameter pack, change the substitution of the parameter
8107 pack to the ith argument in its argument pack, then expand
8109 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8111 tree parm = TREE_PURPOSE (pack);
8113 if (TREE_CODE (parm) == PARM_DECL)
8115 /* Select the Ith argument from the pack. */
8116 tree arg = make_node (ARGUMENT_PACK_SELECT);
8117 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8118 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8120 register_local_specialization (arg, parm);
8126 template_parm_level_and_index (parm, &level, &idx);
8130 /* Select the Ith argument from the pack. */
8131 value = make_node (ARGUMENT_PACK_SELECT);
8132 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8133 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8136 /* Update the corresponding argument. */
8137 TMPL_ARG (args, level, idx) = value;
8141 /* Substitute into the PATTERN with the altered arguments. */
8142 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8143 TREE_VEC_ELT (result, i) =
8144 tsubst_expr (pattern, args, complain, in_decl,
8145 /*integral_constant_expression_p=*/false);
8147 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8150 /* When we have incomplete argument packs, the last "expanded"
8151 result is itself a pack expansion, which allows us
8152 to deduce more arguments. */
8153 TREE_VEC_ELT (result, i) =
8154 make_pack_expansion (TREE_VEC_ELT (result, i));
8156 if (TREE_VEC_ELT (result, i) == error_mark_node)
8158 result = error_mark_node;
8163 /* Update ARGS to restore the substitution from parameter packs to
8164 their argument packs. */
8165 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8167 tree parm = TREE_PURPOSE (pack);
8169 if (TREE_CODE (parm) == PARM_DECL)
8170 register_local_specialization (TREE_TYPE (pack), parm);
8174 template_parm_level_and_index (parm, &level, &idx);
8176 /* Update the corresponding argument. */
8177 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8178 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8181 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8185 if (very_local_specializations)
8187 htab_delete (local_specializations);
8188 local_specializations = NULL;
8194 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8195 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8196 parameter packs; all parms generated from a function parameter pack will
8197 have the same DECL_PARM_INDEX. */
8200 get_pattern_parm (tree parm, tree tmpl)
8202 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8205 if (DECL_ARTIFICIAL (parm))
8207 for (patparm = DECL_ARGUMENTS (pattern);
8208 patparm; patparm = TREE_CHAIN (patparm))
8209 if (DECL_ARTIFICIAL (patparm)
8210 && DECL_NAME (parm) == DECL_NAME (patparm))
8215 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8216 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8217 gcc_assert (DECL_PARM_INDEX (patparm)
8218 == DECL_PARM_INDEX (parm));
8224 /* Substitute ARGS into the vector or list of template arguments T. */
8227 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8230 int len = TREE_VEC_LENGTH (t);
8231 int need_new = 0, i, expanded_len_adjust = 0, out;
8232 tree *elts = (tree *) alloca (len * sizeof (tree));
8234 for (i = 0; i < len; i++)
8236 tree orig_arg = TREE_VEC_ELT (t, i);
8239 if (TREE_CODE (orig_arg) == TREE_VEC)
8240 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8241 else if (PACK_EXPANSION_P (orig_arg))
8243 /* Substitute into an expansion expression. */
8244 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8246 if (TREE_CODE (new_arg) == TREE_VEC)
8247 /* Add to the expanded length adjustment the number of
8248 expanded arguments. We subtract one from this
8249 measurement, because the argument pack expression
8250 itself is already counted as 1 in
8251 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8252 the argument pack is empty. */
8253 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8255 else if (ARGUMENT_PACK_P (orig_arg))
8257 /* Substitute into each of the arguments. */
8258 new_arg = TYPE_P (orig_arg)
8259 ? cxx_make_type (TREE_CODE (orig_arg))
8260 : make_node (TREE_CODE (orig_arg));
8262 SET_ARGUMENT_PACK_ARGS (
8264 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8265 args, complain, in_decl));
8267 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8268 new_arg = error_mark_node;
8270 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8271 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8273 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8275 if (TREE_TYPE (new_arg) == error_mark_node)
8276 new_arg = error_mark_node;
8280 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8282 if (new_arg == error_mark_node)
8283 return error_mark_node;
8286 if (new_arg != orig_arg)
8293 /* Make space for the expanded arguments coming from template
8295 t = make_tree_vec (len + expanded_len_adjust);
8296 for (i = 0, out = 0; i < len; i++)
8298 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8299 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8300 && TREE_CODE (elts[i]) == TREE_VEC)
8304 /* Now expand the template argument pack "in place". */
8305 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8306 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8310 TREE_VEC_ELT (t, out) = elts[i];
8318 /* Return the result of substituting ARGS into the template parameters
8319 given by PARMS. If there are m levels of ARGS and m + n levels of
8320 PARMS, then the result will contain n levels of PARMS. For
8321 example, if PARMS is `template <class T> template <class U>
8322 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8323 result will be `template <int*, double, class V>'. */
8326 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8331 /* When substituting into a template, we must set
8332 PROCESSING_TEMPLATE_DECL as the template parameters may be
8333 dependent if they are based on one-another, and the dependency
8334 predicates are short-circuit outside of templates. */
8335 ++processing_template_decl;
8337 for (new_parms = &r;
8338 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8339 new_parms = &(TREE_CHAIN (*new_parms)),
8340 parms = TREE_CHAIN (parms))
8343 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8346 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8352 if (parms == error_mark_node)
8355 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8357 if (tuple == error_mark_node)
8360 default_value = TREE_PURPOSE (tuple);
8361 parm_decl = TREE_VALUE (tuple);
8363 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8364 if (TREE_CODE (parm_decl) == PARM_DECL
8365 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8366 parm_decl = error_mark_node;
8367 default_value = tsubst_template_arg (default_value, args,
8368 complain, NULL_TREE);
8370 tuple = build_tree_list (default_value, parm_decl);
8371 TREE_VEC_ELT (new_vec, i) = tuple;
8375 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8376 - TMPL_ARGS_DEPTH (args)),
8377 new_vec, NULL_TREE);
8380 --processing_template_decl;
8385 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8386 type T. If T is not an aggregate or enumeration type, it is
8387 handled as if by tsubst. IN_DECL is as for tsubst. If
8388 ENTERING_SCOPE is nonzero, T is the context for a template which
8389 we are presently tsubst'ing. Return the substituted value. */
8392 tsubst_aggr_type (tree t,
8394 tsubst_flags_t complain,
8401 switch (TREE_CODE (t))
8404 if (TYPE_PTRMEMFUNC_P (t))
8405 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8407 /* Else fall through. */
8410 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8415 int saved_unevaluated_operand;
8416 int saved_inhibit_evaluation_warnings;
8418 /* In "sizeof(X<I>)" we need to evaluate "I". */
8419 saved_unevaluated_operand = cp_unevaluated_operand;
8420 cp_unevaluated_operand = 0;
8421 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8422 c_inhibit_evaluation_warnings = 0;
8424 /* First, determine the context for the type we are looking
8426 context = TYPE_CONTEXT (t);
8429 context = tsubst_aggr_type (context, args, complain,
8430 in_decl, /*entering_scope=*/1);
8431 /* If context is a nested class inside a class template,
8432 it may still need to be instantiated (c++/33959). */
8433 if (TYPE_P (context))
8434 context = complete_type (context);
8437 /* Then, figure out what arguments are appropriate for the
8438 type we are trying to find. For example, given:
8440 template <class T> struct S;
8441 template <class T, class U> void f(T, U) { S<U> su; }
8443 and supposing that we are instantiating f<int, double>,
8444 then our ARGS will be {int, double}, but, when looking up
8445 S we only want {double}. */
8446 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8448 if (argvec == error_mark_node)
8449 r = error_mark_node;
8452 r = lookup_template_class (t, argvec, in_decl, context,
8453 entering_scope, complain);
8454 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8457 cp_unevaluated_operand = saved_unevaluated_operand;
8458 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8463 /* This is not a template type, so there's nothing to do. */
8467 return tsubst (t, args, complain, in_decl);
8471 /* Substitute into the default argument ARG (a default argument for
8472 FN), which has the indicated TYPE. */
8475 tsubst_default_argument (tree fn, tree type, tree arg)
8477 tree saved_class_ptr = NULL_TREE;
8478 tree saved_class_ref = NULL_TREE;
8480 /* This default argument came from a template. Instantiate the
8481 default argument here, not in tsubst. In the case of
8490 we must be careful to do name lookup in the scope of S<T>,
8491 rather than in the current class. */
8492 push_access_scope (fn);
8493 /* The "this" pointer is not valid in a default argument. */
8496 saved_class_ptr = current_class_ptr;
8497 cp_function_chain->x_current_class_ptr = NULL_TREE;
8498 saved_class_ref = current_class_ref;
8499 cp_function_chain->x_current_class_ref = NULL_TREE;
8502 push_deferring_access_checks(dk_no_deferred);
8503 /* The default argument expression may cause implicitly defined
8504 member functions to be synthesized, which will result in garbage
8505 collection. We must treat this situation as if we were within
8506 the body of function so as to avoid collecting live data on the
8509 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8510 tf_warning_or_error, NULL_TREE,
8511 /*integral_constant_expression_p=*/false);
8513 pop_deferring_access_checks();
8515 /* Restore the "this" pointer. */
8518 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8519 cp_function_chain->x_current_class_ref = saved_class_ref;
8522 /* Make sure the default argument is reasonable. */
8523 arg = check_default_argument (type, arg);
8525 pop_access_scope (fn);
8530 /* Substitute into all the default arguments for FN. */
8533 tsubst_default_arguments (tree fn)
8538 tmpl_args = DECL_TI_ARGS (fn);
8540 /* If this function is not yet instantiated, we certainly don't need
8541 its default arguments. */
8542 if (uses_template_parms (tmpl_args))
8545 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8547 arg = TREE_CHAIN (arg))
8548 if (TREE_PURPOSE (arg))
8549 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8551 TREE_PURPOSE (arg));
8554 /* Substitute the ARGS into the T, which is a _DECL. Return the
8555 result of the substitution. Issue error and warning messages under
8556 control of COMPLAIN. */
8559 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8561 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8562 location_t saved_loc;
8567 /* Set the filename and linenumber to improve error-reporting. */
8568 saved_loc = input_location;
8569 input_location = DECL_SOURCE_LOCATION (t);
8571 switch (TREE_CODE (t))
8575 /* We can get here when processing a member function template,
8576 member class template, or template template parameter. */
8577 tree decl = DECL_TEMPLATE_RESULT (t);
8582 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8584 /* Template template parameter is treated here. */
8585 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8586 if (new_type == error_mark_node)
8587 RETURN (error_mark_node);
8590 TREE_CHAIN (r) = NULL_TREE;
8591 TREE_TYPE (r) = new_type;
8592 DECL_TEMPLATE_RESULT (r)
8593 = build_decl (DECL_SOURCE_LOCATION (decl),
8594 TYPE_DECL, DECL_NAME (decl), new_type);
8595 DECL_TEMPLATE_PARMS (r)
8596 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8598 TYPE_NAME (new_type) = r;
8602 /* We might already have an instance of this template.
8603 The ARGS are for the surrounding class type, so the
8604 full args contain the tsubst'd args for the context,
8605 plus the innermost args from the template decl. */
8606 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8607 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8608 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8609 /* Because this is a template, the arguments will still be
8610 dependent, even after substitution. If
8611 PROCESSING_TEMPLATE_DECL is not set, the dependency
8612 predicates will short-circuit. */
8613 ++processing_template_decl;
8614 full_args = tsubst_template_args (tmpl_args, args,
8616 --processing_template_decl;
8617 if (full_args == error_mark_node)
8618 RETURN (error_mark_node);
8620 /* If this is a default template template argument,
8621 tsubst might not have changed anything. */
8622 if (full_args == tmpl_args)
8625 hash = hash_tmpl_and_args (t, full_args);
8626 spec = retrieve_specialization (t, full_args, hash);
8627 if (spec != NULL_TREE)
8633 /* Make a new template decl. It will be similar to the
8634 original, but will record the current template arguments.
8635 We also create a new function declaration, which is just
8636 like the old one, but points to this new template, rather
8637 than the old one. */
8639 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8640 TREE_CHAIN (r) = NULL_TREE;
8642 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
8644 if (TREE_CODE (decl) == TYPE_DECL)
8647 ++processing_template_decl;
8648 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8649 --processing_template_decl;
8650 if (new_type == error_mark_node)
8651 RETURN (error_mark_node);
8653 TREE_TYPE (r) = new_type;
8654 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8655 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8656 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8657 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8662 ++processing_template_decl;
8663 new_decl = tsubst (decl, args, complain, in_decl);
8664 --processing_template_decl;
8665 if (new_decl == error_mark_node)
8666 RETURN (error_mark_node);
8668 DECL_TEMPLATE_RESULT (r) = new_decl;
8669 DECL_TI_TEMPLATE (new_decl) = r;
8670 TREE_TYPE (r) = TREE_TYPE (new_decl);
8671 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8672 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8675 SET_DECL_IMPLICIT_INSTANTIATION (r);
8676 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8677 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8679 /* The template parameters for this new template are all the
8680 template parameters for the old template, except the
8681 outermost level of parameters. */
8682 DECL_TEMPLATE_PARMS (r)
8683 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8686 if (PRIMARY_TEMPLATE_P (t))
8687 DECL_PRIMARY_TEMPLATE (r) = r;
8689 if (TREE_CODE (decl) != TYPE_DECL)
8690 /* Record this non-type partial instantiation. */
8691 register_specialization (r, t,
8692 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8700 tree argvec = NULL_TREE;
8708 /* Nobody should be tsubst'ing into non-template functions. */
8709 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8711 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8716 /* If T is not dependent, just return it. We have to
8717 increment PROCESSING_TEMPLATE_DECL because
8718 value_dependent_expression_p assumes that nothing is
8719 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8720 ++processing_template_decl;
8721 dependent_p = value_dependent_expression_p (t);
8722 --processing_template_decl;
8726 /* Calculate the most general template of which R is a
8727 specialization, and the complete set of arguments used to
8729 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8730 argvec = tsubst_template_args (DECL_TI_ARGS
8731 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8732 args, complain, in_decl);
8734 /* Check to see if we already have this specialization. */
8735 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8736 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8744 /* We can see more levels of arguments than parameters if
8745 there was a specialization of a member template, like
8748 template <class T> struct S { template <class U> void f(); }
8749 template <> template <class U> void S<int>::f(U);
8751 Here, we'll be substituting into the specialization,
8752 because that's where we can find the code we actually
8753 want to generate, but we'll have enough arguments for
8754 the most general template.
8756 We also deal with the peculiar case:
8758 template <class T> struct S {
8759 template <class U> friend void f();
8761 template <class U> void f() {}
8763 template void f<double>();
8765 Here, the ARGS for the instantiation of will be {int,
8766 double}. But, we only need as many ARGS as there are
8767 levels of template parameters in CODE_PATTERN. We are
8768 careful not to get fooled into reducing the ARGS in
8771 template <class T> struct S { template <class U> void f(U); }
8772 template <class T> template <> void S<T>::f(int) {}
8774 which we can spot because the pattern will be a
8775 specialization in this case. */
8776 args_depth = TMPL_ARGS_DEPTH (args);
8778 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8779 if (args_depth > parms_depth
8780 && !DECL_TEMPLATE_SPECIALIZATION (t))
8781 args = get_innermost_template_args (args, parms_depth);
8785 /* This special case arises when we have something like this:
8787 template <class T> struct S {
8788 friend void f<int>(int, double);
8791 Here, the DECL_TI_TEMPLATE for the friend declaration
8792 will be an IDENTIFIER_NODE. We are being called from
8793 tsubst_friend_function, and we want only to create a
8794 new decl (R) with appropriate types so that we can call
8795 determine_specialization. */
8796 gen_tmpl = NULL_TREE;
8799 if (DECL_CLASS_SCOPE_P (t))
8801 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8805 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8806 complain, t, /*entering_scope=*/1);
8811 ctx = DECL_CONTEXT (t);
8813 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8814 if (type == error_mark_node)
8815 RETURN (error_mark_node);
8817 /* We do NOT check for matching decls pushed separately at this
8818 point, as they may not represent instantiations of this
8819 template, and in any case are considered separate under the
8822 DECL_USE_TEMPLATE (r) = 0;
8823 TREE_TYPE (r) = type;
8824 /* Clear out the mangled name and RTL for the instantiation. */
8825 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8826 SET_DECL_RTL (r, NULL_RTX);
8827 /* Leave DECL_INITIAL set on deleted instantiations. */
8828 if (!DECL_DELETED_FN (r))
8829 DECL_INITIAL (r) = NULL_TREE;
8830 DECL_CONTEXT (r) = ctx;
8832 if (member && DECL_CONV_FN_P (r))
8833 /* Type-conversion operator. Reconstruct the name, in
8834 case it's the name of one of the template's parameters. */
8835 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8837 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8839 DECL_RESULT (r) = NULL_TREE;
8841 TREE_STATIC (r) = 0;
8842 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8843 DECL_EXTERNAL (r) = 1;
8844 /* If this is an instantiation of a function with internal
8845 linkage, we already know what object file linkage will be
8846 assigned to the instantiation. */
8847 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8848 DECL_DEFER_OUTPUT (r) = 0;
8849 TREE_CHAIN (r) = NULL_TREE;
8850 DECL_PENDING_INLINE_INFO (r) = 0;
8851 DECL_PENDING_INLINE_P (r) = 0;
8852 DECL_SAVED_TREE (r) = NULL_TREE;
8853 DECL_STRUCT_FUNCTION (r) = NULL;
8855 /* We'll re-clone as appropriate in instantiate_template. */
8856 DECL_CLONED_FUNCTION (r) = NULL_TREE;
8858 /* If we aren't complaining now, return on error before we register
8859 the specialization so that we'll complain eventually. */
8860 if ((complain & tf_error) == 0
8861 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8862 && !grok_op_properties (r, /*complain=*/false))
8863 RETURN (error_mark_node);
8865 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8866 this in the special friend case mentioned above where
8867 GEN_TMPL is NULL. */
8870 DECL_TEMPLATE_INFO (r)
8871 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8872 SET_DECL_IMPLICIT_INSTANTIATION (r);
8873 register_specialization (r, gen_tmpl, argvec, false, hash);
8875 /* We're not supposed to instantiate default arguments
8876 until they are called, for a template. But, for a
8879 template <class T> void f ()
8880 { extern void g(int i = T()); }
8882 we should do the substitution when the template is
8883 instantiated. We handle the member function case in
8884 instantiate_class_template since the default arguments
8885 might refer to other members of the class. */
8887 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8888 && !uses_template_parms (argvec))
8889 tsubst_default_arguments (r);
8892 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8894 /* Copy the list of befriending classes. */
8895 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8897 friends = &TREE_CHAIN (*friends))
8899 *friends = copy_node (*friends);
8900 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8905 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8907 maybe_retrofit_in_chrg (r);
8908 if (DECL_CONSTRUCTOR_P (r))
8909 grok_ctor_properties (ctx, r);
8910 /* If this is an instantiation of a member template, clone it.
8911 If it isn't, that'll be handled by
8912 clone_constructors_and_destructors. */
8913 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8914 clone_function_decl (r, /*update_method_vec_p=*/0);
8916 else if ((complain & tf_error) != 0
8917 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8918 && !grok_op_properties (r, /*complain=*/true))
8919 RETURN (error_mark_node);
8921 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8922 SET_DECL_FRIEND_CONTEXT (r,
8923 tsubst (DECL_FRIEND_CONTEXT (t),
8924 args, complain, in_decl));
8926 /* Possibly limit visibility based on template args. */
8927 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8928 if (DECL_VISIBILITY_SPECIFIED (t))
8930 DECL_VISIBILITY_SPECIFIED (r) = 0;
8932 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8934 determine_visibility (r);
8935 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
8936 && !processing_template_decl)
8937 defaulted_late_check (r);
8939 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8940 args, complain, in_decl);
8946 tree type = NULL_TREE;
8948 tree expanded_types = NULL_TREE;
8949 tree prev_r = NULL_TREE;
8950 tree first_r = NULL_TREE;
8952 if (FUNCTION_PARAMETER_PACK_P (t))
8954 /* If there is a local specialization that isn't a
8955 parameter pack, it means that we're doing a "simple"
8956 substitution from inside tsubst_pack_expansion. Just
8957 return the local specialization (which will be a single
8959 tree spec = retrieve_local_specialization (t);
8961 && TREE_CODE (spec) == PARM_DECL
8962 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8965 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8966 the parameters in this function parameter pack. */
8967 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8969 if (TREE_CODE (expanded_types) == TREE_VEC)
8971 len = TREE_VEC_LENGTH (expanded_types);
8973 /* Zero-length parameter packs are boring. Just substitute
8976 RETURN (tsubst (TREE_CHAIN (t), args, complain,
8981 /* All we did was update the type. Make a note of that. */
8982 type = expanded_types;
8983 expanded_types = NULL_TREE;
8987 /* Loop through all of the parameter's we'll build. When T is
8988 a function parameter pack, LEN is the number of expanded
8989 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8991 for (i = 0; i < len; ++i)
8995 if (DECL_TEMPLATE_PARM_P (t))
8996 SET_DECL_TEMPLATE_PARM_P (r);
8998 /* An argument of a function parameter pack is not a parameter
9000 FUNCTION_PARAMETER_PACK_P (r) = false;
9003 /* We're on the Ith parameter of the function parameter
9006 /* Get the Ith type. */
9007 type = TREE_VEC_ELT (expanded_types, i);
9010 /* Rename the parameter to include the index. */
9012 make_ith_pack_parameter_name (DECL_NAME (r), i);
9015 /* We're dealing with a normal parameter. */
9016 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9018 type = type_decays_to (type);
9019 TREE_TYPE (r) = type;
9020 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9022 if (DECL_INITIAL (r))
9024 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9025 DECL_INITIAL (r) = TREE_TYPE (r);
9027 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9031 DECL_CONTEXT (r) = NULL_TREE;
9033 if (!DECL_TEMPLATE_PARM_P (r))
9034 DECL_ARG_TYPE (r) = type_passed_as (type);
9036 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9037 args, complain, in_decl);
9039 /* Keep track of the first new parameter we
9040 generate. That's what will be returned to the
9045 /* Build a proper chain of parameters when substituting
9046 into a function parameter pack. */
9048 TREE_CHAIN (prev_r) = r;
9052 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
9053 complain, TREE_CHAIN (t));
9055 /* FIRST_R contains the start of the chain we've built. */
9065 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9066 if (type == error_mark_node)
9067 RETURN (error_mark_node);
9068 TREE_TYPE (r) = type;
9069 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9071 /* DECL_INITIAL gives the number of bits in a bit-field. */
9073 = tsubst_expr (DECL_INITIAL (t), args,
9075 /*integral_constant_expression_p=*/true);
9076 /* We don't have to set DECL_CONTEXT here; it is set by
9077 finish_member_declaration. */
9078 TREE_CHAIN (r) = NULL_TREE;
9079 if (VOID_TYPE_P (type))
9080 error ("instantiation of %q+D as type %qT", r, type);
9082 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9083 args, complain, in_decl);
9088 /* We reach here only for member using decls. */
9089 if (DECL_DEPENDENT_P (t))
9091 r = do_class_using_decl
9092 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9093 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9095 r = error_mark_node;
9098 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9099 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9105 TREE_CHAIN (r) = NULL_TREE;
9112 tree argvec = NULL_TREE;
9113 tree gen_tmpl = NULL_TREE;
9115 tree tmpl = NULL_TREE;
9117 tree type = NULL_TREE;
9120 if (TREE_CODE (t) == TYPE_DECL
9121 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9123 /* If this is the canonical decl, we don't have to
9124 mess with instantiations, and often we can't (for
9125 typename, template type parms and such). Note that
9126 TYPE_NAME is not correct for the above test if
9127 we've copied the type for a typedef. */
9128 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9129 if (type == error_mark_node)
9130 RETURN (error_mark_node);
9131 r = TYPE_NAME (type);
9135 /* Check to see if we already have the specialization we
9138 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9140 /* T is a static data member or namespace-scope entity.
9141 We have to substitute into namespace-scope variables
9142 (even though such entities are never templates) because
9145 template <class T> void f() { extern T t; }
9147 where the entity referenced is not known until
9148 instantiation time. */
9150 ctx = DECL_CONTEXT (t);
9151 if (DECL_CLASS_SCOPE_P (t))
9153 ctx = tsubst_aggr_type (ctx, args,
9155 in_decl, /*entering_scope=*/1);
9156 /* If CTX is unchanged, then T is in fact the
9157 specialization we want. That situation occurs when
9158 referencing a static data member within in its own
9159 class. We can use pointer equality, rather than
9160 same_type_p, because DECL_CONTEXT is always
9162 if (ctx == DECL_CONTEXT (t))
9168 tmpl = DECL_TI_TEMPLATE (t);
9169 gen_tmpl = most_general_template (tmpl);
9170 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9171 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9172 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9177 /* A local variable. */
9179 /* Subsequent calls to pushdecl will fill this in. */
9181 spec = retrieve_local_specialization (t);
9183 /* If we already have the specialization we need, there is
9184 nothing more to do. */
9191 /* Create a new node for the specialization we need. */
9193 if (type == NULL_TREE)
9194 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9195 if (TREE_CODE (r) == VAR_DECL)
9197 /* Even if the original location is out of scope, the
9198 newly substituted one is not. */
9199 DECL_DEAD_FOR_LOCAL (r) = 0;
9200 DECL_INITIALIZED_P (r) = 0;
9201 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9202 if (type == error_mark_node)
9203 RETURN (error_mark_node);
9204 if (TREE_CODE (type) == FUNCTION_TYPE)
9206 /* It may seem that this case cannot occur, since:
9211 declares a function, not a variable. However:
9214 template <typename T> void g() { T t; }
9215 template void g<f>();
9217 is an attempt to declare a variable with function
9219 error ("variable %qD has function type",
9220 /* R is not yet sufficiently initialized, so we
9221 just use its name. */
9223 RETURN (error_mark_node);
9225 type = complete_type (type);
9226 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9227 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9228 type = check_var_type (DECL_NAME (r), type);
9230 if (DECL_HAS_VALUE_EXPR_P (t))
9232 tree ve = DECL_VALUE_EXPR (t);
9233 ve = tsubst_expr (ve, args, complain, in_decl,
9234 /*constant_expression_p=*/false);
9235 SET_DECL_VALUE_EXPR (r, ve);
9238 else if (DECL_SELF_REFERENCE_P (t))
9239 SET_DECL_SELF_REFERENCE_P (r);
9240 TREE_TYPE (r) = type;
9241 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9242 DECL_CONTEXT (r) = ctx;
9243 /* Clear out the mangled name and RTL for the instantiation. */
9244 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9245 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9246 SET_DECL_RTL (r, NULL_RTX);
9247 /* The initializer must not be expanded until it is required;
9249 DECL_INITIAL (r) = NULL_TREE;
9250 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9251 SET_DECL_RTL (r, NULL_RTX);
9252 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9253 if (TREE_CODE (r) == VAR_DECL)
9255 /* Possibly limit visibility based on template args. */
9256 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9257 if (DECL_VISIBILITY_SPECIFIED (t))
9259 DECL_VISIBILITY_SPECIFIED (r) = 0;
9261 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9263 determine_visibility (r);
9265 /* Preserve a typedef that names a type. */
9266 else if (TREE_CODE (r) == TYPE_DECL
9267 && DECL_ORIGINAL_TYPE (t)
9268 && type != error_mark_node)
9270 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
9271 args, complain, in_decl);
9272 TREE_TYPE (r) = type = build_variant_type_copy (type);
9273 TYPE_NAME (type) = r;
9278 /* A static data member declaration is always marked
9279 external when it is declared in-class, even if an
9280 initializer is present. We mimic the non-template
9282 DECL_EXTERNAL (r) = 1;
9284 register_specialization (r, gen_tmpl, argvec, false, hash);
9285 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
9286 SET_DECL_IMPLICIT_INSTANTIATION (r);
9288 else if (cp_unevaluated_operand)
9290 /* We're substituting this var in a decltype outside of its
9291 scope, such as for a lambda return type. Don't add it to
9292 local_specializations, do perform auto deduction. */
9293 tree auto_node = type_uses_auto (type);
9295 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9296 /*constant_expression_p=*/false);
9298 if (auto_node && init && describable_type (init))
9300 type = do_auto_deduction (type, init, auto_node);
9301 TREE_TYPE (r) = type;
9305 register_local_specialization (r, t);
9307 TREE_CHAIN (r) = NULL_TREE;
9309 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9310 (int) ATTR_FLAG_TYPE_IN_PLACE,
9311 args, complain, in_decl);
9322 /* Restore the file and line information. */
9323 input_location = saved_loc;
9328 /* Substitute into the ARG_TYPES of a function type. */
9331 tsubst_arg_types (tree arg_types,
9333 tsubst_flags_t complain,
9336 tree remaining_arg_types;
9337 tree type = NULL_TREE;
9339 tree expanded_args = NULL_TREE;
9342 if (!arg_types || arg_types == void_list_node)
9345 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9346 args, complain, in_decl);
9347 if (remaining_arg_types == error_mark_node)
9348 return error_mark_node;
9350 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9352 /* For a pack expansion, perform substitution on the
9353 entire expression. Later on, we'll handle the arguments
9355 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9356 args, complain, in_decl);
9358 if (TREE_CODE (expanded_args) == TREE_VEC)
9359 /* So that we'll spin through the parameters, one by one. */
9360 i = TREE_VEC_LENGTH (expanded_args);
9363 /* We only partially substituted into the parameter
9364 pack. Our type is TYPE_PACK_EXPANSION. */
9365 type = expanded_args;
9366 expanded_args = NULL_TREE;
9374 type = TREE_VEC_ELT (expanded_args, i);
9376 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9378 if (type == error_mark_node)
9379 return error_mark_node;
9380 if (VOID_TYPE_P (type))
9382 if (complain & tf_error)
9384 error ("invalid parameter type %qT", type);
9386 error ("in declaration %q+D", in_decl);
9388 return error_mark_node;
9391 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9392 top-level qualifiers as required. */
9393 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9395 /* We do not substitute into default arguments here. The standard
9396 mandates that they be instantiated only when needed, which is
9397 done in build_over_call. */
9398 default_arg = TREE_PURPOSE (arg_types);
9400 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9402 /* We've instantiated a template before its default arguments
9403 have been parsed. This can happen for a nested template
9404 class, and is not an error unless we require the default
9405 argument in a call of this function. */
9406 remaining_arg_types =
9407 tree_cons (default_arg, type, remaining_arg_types);
9408 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9409 remaining_arg_types);
9412 remaining_arg_types =
9413 hash_tree_cons (default_arg, type, remaining_arg_types);
9416 return remaining_arg_types;
9419 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9420 *not* handle the exception-specification for FNTYPE, because the
9421 initial substitution of explicitly provided template parameters
9422 during argument deduction forbids substitution into the
9423 exception-specification:
9427 All references in the function type of the function template to the
9428 corresponding template parameters are replaced by the specified tem-
9429 plate argument values. If a substitution in a template parameter or
9430 in the function type of the function template results in an invalid
9431 type, type deduction fails. [Note: The equivalent substitution in
9432 exception specifications is done only when the function is instanti-
9433 ated, at which point a program is ill-formed if the substitution
9434 results in an invalid type.] */
9437 tsubst_function_type (tree t,
9439 tsubst_flags_t complain,
9446 /* The TYPE_CONTEXT is not used for function/method types. */
9447 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9449 /* Substitute the return type. */
9450 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9451 if (return_type == error_mark_node)
9452 return error_mark_node;
9453 /* The standard does not presently indicate that creation of a
9454 function type with an invalid return type is a deduction failure.
9455 However, that is clearly analogous to creating an array of "void"
9456 or a reference to a reference. This is core issue #486. */
9457 if (TREE_CODE (return_type) == ARRAY_TYPE
9458 || TREE_CODE (return_type) == FUNCTION_TYPE)
9460 if (complain & tf_error)
9462 if (TREE_CODE (return_type) == ARRAY_TYPE)
9463 error ("function returning an array");
9465 error ("function returning a function");
9467 return error_mark_node;
9470 /* Substitute the argument types. */
9471 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9473 if (arg_types == error_mark_node)
9474 return error_mark_node;
9476 /* Construct a new type node and return it. */
9477 if (TREE_CODE (t) == FUNCTION_TYPE)
9478 fntype = build_function_type (return_type, arg_types);
9481 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9482 if (! MAYBE_CLASS_TYPE_P (r))
9486 Type deduction may fail for any of the following
9489 -- Attempting to create "pointer to member of T" when T
9490 is not a class type. */
9491 if (complain & tf_error)
9492 error ("creating pointer to member function of non-class type %qT",
9494 return error_mark_node;
9497 fntype = build_method_type_directly (r, return_type,
9498 TREE_CHAIN (arg_types));
9500 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9501 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9506 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9507 ARGS into that specification, and return the substituted
9508 specification. If there is no specification, return NULL_TREE. */
9511 tsubst_exception_specification (tree fntype,
9513 tsubst_flags_t complain,
9519 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9520 new_specs = NULL_TREE;
9523 if (! TREE_VALUE (specs))
9530 tree expanded_specs = NULL_TREE;
9532 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9534 /* Expand the pack expansion type. */
9535 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9539 if (expanded_specs == error_mark_node)
9540 return error_mark_node;
9541 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9542 len = TREE_VEC_LENGTH (expanded_specs);
9545 /* We're substituting into a member template, so
9546 we got a TYPE_PACK_EXPANSION back. Add that
9547 expansion and move on. */
9548 gcc_assert (TREE_CODE (expanded_specs)
9549 == TYPE_PACK_EXPANSION);
9550 new_specs = add_exception_specifier (new_specs,
9553 specs = TREE_CHAIN (specs);
9558 for (i = 0; i < len; ++i)
9561 spec = TREE_VEC_ELT (expanded_specs, i);
9563 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9564 if (spec == error_mark_node)
9566 new_specs = add_exception_specifier (new_specs, spec,
9570 specs = TREE_CHAIN (specs);
9576 /* Take the tree structure T and replace template parameters used
9577 therein with the argument vector ARGS. IN_DECL is an associated
9578 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9579 Issue error and warning messages under control of COMPLAIN. Note
9580 that we must be relatively non-tolerant of extensions here, in
9581 order to preserve conformance; if we allow substitutions that
9582 should not be allowed, we may allow argument deductions that should
9583 not succeed, and therefore report ambiguous overload situations
9584 where there are none. In theory, we could allow the substitution,
9585 but indicate that it should have failed, and allow our caller to
9586 make sure that the right thing happens, but we don't try to do this
9589 This function is used for dealing with types, decls and the like;
9590 for expressions, use tsubst_expr or tsubst_copy. */
9593 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9597 if (t == NULL_TREE || t == error_mark_node
9598 || t == integer_type_node
9599 || t == void_type_node
9600 || t == char_type_node
9601 || t == unknown_type_node
9602 || TREE_CODE (t) == NAMESPACE_DECL)
9606 return tsubst_decl (t, args, complain);
9608 if (args == NULL_TREE)
9611 if (TREE_CODE (t) == IDENTIFIER_NODE)
9612 type = IDENTIFIER_TYPE_VALUE (t);
9614 type = TREE_TYPE (t);
9616 gcc_assert (type != unknown_type_node);
9618 /* Reuse typedefs. We need to do this to handle dependent attributes,
9619 such as attribute aligned. */
9622 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9624 tree decl = TYPE_NAME (t);
9626 if (DECL_CLASS_SCOPE_P (decl)
9627 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9628 && uses_template_parms (DECL_CONTEXT (decl)))
9630 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9631 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9632 r = retrieve_specialization (tmpl, gen_args, 0);
9634 else if (DECL_FUNCTION_SCOPE_P (decl)
9635 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9636 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9637 r = retrieve_local_specialization (decl);
9639 /* The typedef is from a non-template context. */
9645 r = cp_build_qualified_type_real
9646 (r, cp_type_quals (t) | cp_type_quals (r),
9647 complain | tf_ignore_bad_quals);
9650 /* Else we must be instantiating the typedef, so fall through. */
9654 && TREE_CODE (t) != TYPENAME_TYPE
9655 && TREE_CODE (t) != IDENTIFIER_NODE
9656 && TREE_CODE (t) != FUNCTION_TYPE
9657 && TREE_CODE (t) != METHOD_TYPE)
9658 type = tsubst (type, args, complain, in_decl);
9659 if (type == error_mark_node)
9660 return error_mark_node;
9662 switch (TREE_CODE (t))
9667 return tsubst_aggr_type (t, args, complain, in_decl,
9668 /*entering_scope=*/0);
9671 case IDENTIFIER_NODE:
9683 if (t == integer_type_node)
9686 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9687 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9691 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9693 max = tsubst_expr (omax, args, complain, in_decl,
9694 /*integral_constant_expression_p=*/false);
9696 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9698 if (TREE_CODE (max) == NOP_EXPR
9699 && TREE_SIDE_EFFECTS (omax)
9700 && !TREE_TYPE (max))
9701 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9703 max = fold_decl_constant_value (max);
9705 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9706 with TREE_SIDE_EFFECTS that indicates this is not an integral
9707 constant expression. */
9708 if (processing_template_decl
9709 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9711 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9712 TREE_SIDE_EFFECTS (max) = 1;
9715 if (TREE_CODE (max) != INTEGER_CST
9716 && !at_function_scope_p ()
9717 && !TREE_SIDE_EFFECTS (max)
9718 && !value_dependent_expression_p (max))
9720 if (complain & tf_error)
9721 error ("array bound is not an integer constant");
9722 return error_mark_node;
9727 Type deduction may fail for any of the following
9730 Attempting to create an array with a size that is
9731 zero or negative. */
9732 if (integer_zerop (max) && !(complain & tf_error))
9733 /* We must fail if performing argument deduction (as
9734 indicated by the state of complain), so that
9735 another substitution can be found. */
9736 return error_mark_node;
9737 else if (TREE_CODE (max) == INTEGER_CST
9738 && INT_CST_LT (max, integer_zero_node))
9740 if (complain & tf_error)
9741 error ("creating array with negative size (%qE)", max);
9743 return error_mark_node;
9746 return compute_array_index_type (NULL_TREE, max);
9749 case TEMPLATE_TYPE_PARM:
9750 case TEMPLATE_TEMPLATE_PARM:
9751 case BOUND_TEMPLATE_TEMPLATE_PARM:
9752 case TEMPLATE_PARM_INDEX:
9757 tree arg = NULL_TREE;
9761 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9762 template_parm_level_and_index (t, &level, &idx);
9764 levels = TMPL_ARGS_DEPTH (args);
9765 if (level <= levels)
9767 arg = TMPL_ARG (args, level, idx);
9769 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9770 /* See through ARGUMENT_PACK_SELECT arguments. */
9771 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9774 if (arg == error_mark_node)
9775 return error_mark_node;
9776 else if (arg != NULL_TREE)
9778 if (ARGUMENT_PACK_P (arg))
9779 /* If ARG is an argument pack, we don't actually want to
9780 perform a substitution here, because substitutions
9781 for argument packs are only done
9782 element-by-element. We can get to this point when
9783 substituting the type of a non-type template
9784 parameter pack, when that type actually contains
9785 template parameter packs from an outer template, e.g.,
9787 template<typename... Types> struct A {
9788 template<Types... Values> struct B { };
9792 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9795 gcc_assert (TYPE_P (arg));
9797 /* cv-quals from the template are discarded when
9798 substituting in a function or reference type. */
9799 if (TREE_CODE (arg) == FUNCTION_TYPE
9800 || TREE_CODE (arg) == METHOD_TYPE
9801 || TREE_CODE (arg) == REFERENCE_TYPE)
9802 quals = cp_type_quals (arg);
9804 quals = cp_type_quals (arg) | cp_type_quals (t);
9806 return cp_build_qualified_type_real
9807 (arg, quals, complain | tf_ignore_bad_quals);
9809 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9811 /* We are processing a type constructed from a
9812 template template parameter. */
9813 tree argvec = tsubst (TYPE_TI_ARGS (t),
9814 args, complain, in_decl);
9815 if (argvec == error_mark_node)
9816 return error_mark_node;
9818 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9819 are resolving nested-types in the signature of a
9820 member function templates. Otherwise ARG is a
9821 TEMPLATE_DECL and is the real template to be
9823 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9824 arg = TYPE_NAME (arg);
9826 r = lookup_template_class (arg,
9829 /*entering_scope=*/0,
9831 return cp_build_qualified_type_real
9832 (r, TYPE_QUALS (t), complain);
9835 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9840 /* This can happen during the attempted tsubst'ing in
9841 unify. This means that we don't yet have any information
9842 about the template parameter in question. */
9845 /* If we get here, we must have been looking at a parm for a
9846 more deeply nested template. Make a new version of this
9847 template parameter, but with a lower level. */
9848 switch (TREE_CODE (t))
9850 case TEMPLATE_TYPE_PARM:
9851 case TEMPLATE_TEMPLATE_PARM:
9852 case BOUND_TEMPLATE_TEMPLATE_PARM:
9853 if (cp_type_quals (t))
9855 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9856 r = cp_build_qualified_type_real
9857 (r, cp_type_quals (t),
9858 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9859 ? tf_ignore_bad_quals : 0));
9864 TEMPLATE_TYPE_PARM_INDEX (r)
9865 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9866 r, levels, args, complain);
9867 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9868 TYPE_MAIN_VARIANT (r) = r;
9869 TYPE_POINTER_TO (r) = NULL_TREE;
9870 TYPE_REFERENCE_TO (r) = NULL_TREE;
9872 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9873 /* We have reduced the level of the template
9874 template parameter, but not the levels of its
9875 template parameters, so canonical_type_parameter
9876 will not be able to find the canonical template
9877 template parameter for this level. Thus, we
9878 require structural equality checking to compare
9879 TEMPLATE_TEMPLATE_PARMs. */
9880 SET_TYPE_STRUCTURAL_EQUALITY (r);
9881 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9882 SET_TYPE_STRUCTURAL_EQUALITY (r);
9884 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9886 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9888 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9890 if (argvec == error_mark_node)
9891 return error_mark_node;
9893 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9894 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9899 case TEMPLATE_PARM_INDEX:
9900 r = reduce_template_parm_level (t, type, levels, args, complain);
9912 tree purpose, value, chain;
9914 if (t == void_list_node)
9917 purpose = TREE_PURPOSE (t);
9920 purpose = tsubst (purpose, args, complain, in_decl);
9921 if (purpose == error_mark_node)
9922 return error_mark_node;
9924 value = TREE_VALUE (t);
9927 value = tsubst (value, args, complain, in_decl);
9928 if (value == error_mark_node)
9929 return error_mark_node;
9931 chain = TREE_CHAIN (t);
9932 if (chain && chain != void_type_node)
9934 chain = tsubst (chain, args, complain, in_decl);
9935 if (chain == error_mark_node)
9936 return error_mark_node;
9938 if (purpose == TREE_PURPOSE (t)
9939 && value == TREE_VALUE (t)
9940 && chain == TREE_CHAIN (t))
9942 return hash_tree_cons (purpose, value, chain);
9946 /* We should never be tsubsting a binfo. */
9950 /* A vector of template arguments. */
9952 return tsubst_template_args (t, args, complain, in_decl);
9955 case REFERENCE_TYPE:
9957 enum tree_code code;
9959 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9962 code = TREE_CODE (t);
9967 Type deduction may fail for any of the following
9970 -- Attempting to create a pointer to reference type.
9971 -- Attempting to create a reference to a reference type or
9972 a reference to void.
9974 Core issue 106 says that creating a reference to a reference
9975 during instantiation is no longer a cause for failure. We
9976 only enforce this check in strict C++98 mode. */
9977 if ((TREE_CODE (type) == REFERENCE_TYPE
9978 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9979 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9981 static location_t last_loc;
9983 /* We keep track of the last time we issued this error
9984 message to avoid spewing a ton of messages during a
9985 single bad template instantiation. */
9986 if (complain & tf_error
9987 && last_loc != input_location)
9989 if (TREE_CODE (type) == VOID_TYPE)
9990 error ("forming reference to void");
9992 error ("forming %s to reference type %qT",
9993 (code == POINTER_TYPE) ? "pointer" : "reference",
9995 last_loc = input_location;
9998 return error_mark_node;
10000 else if (code == POINTER_TYPE)
10002 r = build_pointer_type (type);
10003 if (TREE_CODE (type) == METHOD_TYPE)
10004 r = build_ptrmemfunc_type (r);
10006 else if (TREE_CODE (type) == REFERENCE_TYPE)
10007 /* In C++0x, during template argument substitution, when there is an
10008 attempt to create a reference to a reference type, reference
10009 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10011 "If a template-argument for a template-parameter T names a type
10012 that is a reference to a type A, an attempt to create the type
10013 'lvalue reference to cv T' creates the type 'lvalue reference to
10014 A,' while an attempt to create the type type rvalue reference to
10015 cv T' creates the type T"
10017 r = cp_build_reference_type
10019 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10021 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10022 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
10024 if (r != error_mark_node)
10025 /* Will this ever be needed for TYPE_..._TO values? */
10032 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10033 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10037 Type deduction may fail for any of the following
10040 -- Attempting to create "pointer to member of T" when T
10041 is not a class type. */
10042 if (complain & tf_error)
10043 error ("creating pointer to member of non-class type %qT", r);
10044 return error_mark_node;
10046 if (TREE_CODE (type) == REFERENCE_TYPE)
10048 if (complain & tf_error)
10049 error ("creating pointer to member reference type %qT", type);
10050 return error_mark_node;
10052 if (TREE_CODE (type) == VOID_TYPE)
10054 if (complain & tf_error)
10055 error ("creating pointer to member of type void");
10056 return error_mark_node;
10058 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10059 if (TREE_CODE (type) == FUNCTION_TYPE)
10061 /* The type of the implicit object parameter gets its
10062 cv-qualifiers from the FUNCTION_TYPE. */
10064 tree method_type = build_memfn_type (type, r, cp_type_quals (type));
10065 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10066 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10070 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10074 case FUNCTION_TYPE:
10079 fntype = tsubst_function_type (t, args, complain, in_decl);
10080 if (fntype == error_mark_node)
10081 return error_mark_node;
10083 /* Substitute the exception specification. */
10084 specs = tsubst_exception_specification (t, args, complain,
10086 if (specs == error_mark_node)
10087 return error_mark_node;
10089 fntype = build_exception_variant (fntype, specs);
10094 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10095 if (domain == error_mark_node)
10096 return error_mark_node;
10098 /* As an optimization, we avoid regenerating the array type if
10099 it will obviously be the same as T. */
10100 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10103 /* These checks should match the ones in grokdeclarator.
10107 The deduction may fail for any of the following reasons:
10109 -- Attempting to create an array with an element type that
10110 is void, a function type, or a reference type, or [DR337]
10111 an abstract class type. */
10112 if (TREE_CODE (type) == VOID_TYPE
10113 || TREE_CODE (type) == FUNCTION_TYPE
10114 || TREE_CODE (type) == REFERENCE_TYPE)
10116 if (complain & tf_error)
10117 error ("creating array of %qT", type);
10118 return error_mark_node;
10120 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10122 if (complain & tf_error)
10123 error ("creating array of %qT, which is an abstract class type",
10125 return error_mark_node;
10128 r = build_cplus_array_type (type, domain);
10130 if (TYPE_USER_ALIGN (t))
10132 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10133 TYPE_USER_ALIGN (r) = 1;
10142 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10143 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10145 if (e1 == error_mark_node || e2 == error_mark_node)
10146 return error_mark_node;
10148 return fold_build2_loc (input_location,
10149 TREE_CODE (t), TREE_TYPE (t), e1, e2);
10155 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10156 if (e == error_mark_node)
10157 return error_mark_node;
10159 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
10162 case TYPENAME_TYPE:
10164 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10165 in_decl, /*entering_scope=*/1);
10166 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10167 complain, in_decl);
10169 if (ctx == error_mark_node || f == error_mark_node)
10170 return error_mark_node;
10172 if (!MAYBE_CLASS_TYPE_P (ctx))
10174 if (complain & tf_error)
10175 error ("%qT is not a class, struct, or union type", ctx);
10176 return error_mark_node;
10178 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10180 /* Normally, make_typename_type does not require that the CTX
10181 have complete type in order to allow things like:
10183 template <class T> struct S { typename S<T>::X Y; };
10185 But, such constructs have already been resolved by this
10186 point, so here CTX really should have complete type, unless
10187 it's a partial instantiation. */
10188 if (!(complain & tf_no_class_instantiations))
10189 ctx = complete_type (ctx);
10190 if (!COMPLETE_TYPE_P (ctx))
10192 if (complain & tf_error)
10193 cxx_incomplete_type_error (NULL_TREE, ctx);
10194 return error_mark_node;
10198 f = make_typename_type (ctx, f, typename_type,
10199 (complain & tf_error) | tf_keep_type_decl);
10200 if (f == error_mark_node)
10202 if (TREE_CODE (f) == TYPE_DECL)
10204 complain |= tf_ignore_bad_quals;
10208 if (TREE_CODE (f) != TYPENAME_TYPE)
10210 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10211 error ("%qT resolves to %qT, which is not an enumeration type",
10213 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10214 error ("%qT resolves to %qT, which is is not a class type",
10218 return cp_build_qualified_type_real
10219 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10222 case UNBOUND_CLASS_TEMPLATE:
10224 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10225 in_decl, /*entering_scope=*/1);
10226 tree name = TYPE_IDENTIFIER (t);
10227 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10229 if (ctx == error_mark_node || name == error_mark_node)
10230 return error_mark_node;
10233 parm_list = tsubst_template_parms (parm_list, args, complain);
10234 return make_unbound_class_template (ctx, name, parm_list, complain);
10240 gcc_unreachable ();
10244 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10245 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10246 /*integral_constant_expression_p=*/false);
10247 if (e1 == error_mark_node || e2 == error_mark_node)
10248 return error_mark_node;
10250 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10255 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10256 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10257 if (e1 == error_mark_node || e2 == error_mark_node)
10258 return error_mark_node;
10260 return build_qualified_name (/*type=*/NULL_TREE,
10261 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10268 ++cp_unevaluated_operand;
10269 ++c_inhibit_evaluation_warnings;
10271 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10273 /*integral_constant_expression_p=*/false);
10275 --cp_unevaluated_operand;
10276 --c_inhibit_evaluation_warnings;
10278 type = finish_typeof (type);
10279 return cp_build_qualified_type_real (type,
10281 | cp_type_quals (type),
10285 case DECLTYPE_TYPE:
10289 ++cp_unevaluated_operand;
10290 ++c_inhibit_evaluation_warnings;
10292 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10294 /*integral_constant_expression_p=*/false);
10296 --cp_unevaluated_operand;
10297 --c_inhibit_evaluation_warnings;
10299 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10300 type = lambda_capture_field_type (type);
10301 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10302 type = lambda_return_type (type);
10304 type = finish_decltype_type
10305 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10306 return cp_build_qualified_type_real (type,
10308 | cp_type_quals (type),
10312 case TYPE_ARGUMENT_PACK:
10313 case NONTYPE_ARGUMENT_PACK:
10315 tree r = TYPE_P (t)
10316 ? cxx_make_type (TREE_CODE (t))
10317 : make_node (TREE_CODE (t));
10319 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10323 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10325 /* For template nontype argument packs, also substitute into
10327 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10328 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10335 sorry ("use of %qs in template",
10336 tree_code_name [(int) TREE_CODE (t)]);
10337 return error_mark_node;
10341 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10342 type of the expression on the left-hand side of the "." or "->"
10346 tsubst_baselink (tree baselink, tree object_type,
10347 tree args, tsubst_flags_t complain, tree in_decl)
10350 tree qualifying_scope;
10353 tree template_args = 0;
10354 bool template_id_p = false;
10356 /* A baselink indicates a function from a base class. Both the
10357 BASELINK_ACCESS_BINFO and the base class referenced may
10358 indicate bases of the template class, rather than the
10359 instantiated class. In addition, lookups that were not
10360 ambiguous before may be ambiguous now. Therefore, we perform
10361 the lookup again. */
10362 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10363 qualifying_scope = tsubst (qualifying_scope, args,
10364 complain, in_decl);
10365 fns = BASELINK_FUNCTIONS (baselink);
10366 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
10367 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10369 template_id_p = true;
10370 template_args = TREE_OPERAND (fns, 1);
10371 fns = TREE_OPERAND (fns, 0);
10373 template_args = tsubst_template_args (template_args, args,
10374 complain, in_decl);
10376 name = DECL_NAME (get_first_fn (fns));
10377 if (IDENTIFIER_TYPENAME_P (name))
10378 name = mangle_conv_op_name_for_type (optype);
10379 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10381 /* If lookup found a single function, mark it as used at this
10382 point. (If it lookup found multiple functions the one selected
10383 later by overload resolution will be marked as used at that
10385 if (BASELINK_P (baselink))
10386 fns = BASELINK_FUNCTIONS (baselink);
10387 if (!template_id_p && !really_overloaded_fn (fns))
10388 mark_used (OVL_CURRENT (fns));
10390 /* Add back the template arguments, if present. */
10391 if (BASELINK_P (baselink) && template_id_p)
10392 BASELINK_FUNCTIONS (baselink)
10393 = build_nt (TEMPLATE_ID_EXPR,
10394 BASELINK_FUNCTIONS (baselink),
10396 /* Update the conversion operator type. */
10397 BASELINK_OPTYPE (baselink) = optype;
10400 object_type = current_class_type;
10401 return adjust_result_of_qualified_name_lookup (baselink,
10406 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10407 true if the qualified-id will be a postfix-expression in-and-of
10408 itself; false if more of the postfix-expression follows the
10409 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10413 tsubst_qualified_id (tree qualified_id, tree args,
10414 tsubst_flags_t complain, tree in_decl,
10415 bool done, bool address_p)
10421 tree template_args;
10423 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10425 /* Figure out what name to look up. */
10426 name = TREE_OPERAND (qualified_id, 1);
10427 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10429 is_template = true;
10430 template_args = TREE_OPERAND (name, 1);
10432 template_args = tsubst_template_args (template_args, args,
10433 complain, in_decl);
10434 name = TREE_OPERAND (name, 0);
10438 is_template = false;
10439 template_args = NULL_TREE;
10442 /* Substitute into the qualifying scope. When there are no ARGS, we
10443 are just trying to simplify a non-dependent expression. In that
10444 case the qualifying scope may be dependent, and, in any case,
10445 substituting will not help. */
10446 scope = TREE_OPERAND (qualified_id, 0);
10449 scope = tsubst (scope, args, complain, in_decl);
10450 expr = tsubst_copy (name, args, complain, in_decl);
10455 if (dependent_type_p (scope))
10457 tree type = NULL_TREE;
10458 if (DECL_P (expr) && !dependent_scope_p (scope))
10459 type = TREE_TYPE (expr);
10460 return build_qualified_name (type, scope, expr,
10461 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10464 if (!BASELINK_P (name) && !DECL_P (expr))
10466 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10468 /* A BIT_NOT_EXPR is used to represent a destructor. */
10469 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10471 error ("qualifying type %qT does not match destructor name ~%qT",
10472 scope, TREE_OPERAND (expr, 0));
10473 expr = error_mark_node;
10476 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10477 /*is_type_p=*/0, false);
10480 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10481 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10482 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10484 if (complain & tf_error)
10486 error ("dependent-name %qE is parsed as a non-type, but "
10487 "instantiation yields a type", qualified_id);
10488 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10490 return error_mark_node;
10496 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10498 /* Remember that there was a reference to this entity. */
10502 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10504 if (complain & tf_error)
10505 qualified_name_lookup_error (scope,
10506 TREE_OPERAND (qualified_id, 1),
10507 expr, input_location);
10508 return error_mark_node;
10512 expr = lookup_template_function (expr, template_args);
10514 if (expr == error_mark_node && complain & tf_error)
10515 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10516 expr, input_location);
10517 else if (TYPE_P (scope))
10519 expr = (adjust_result_of_qualified_name_lookup
10520 (expr, scope, current_class_type));
10521 expr = (finish_qualified_id_expr
10522 (scope, expr, done, address_p,
10523 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10524 /*template_arg_p=*/false));
10527 /* Expressions do not generally have reference type. */
10528 if (TREE_CODE (expr) != SCOPE_REF
10529 /* However, if we're about to form a pointer-to-member, we just
10530 want the referenced member referenced. */
10531 && TREE_CODE (expr) != OFFSET_REF)
10532 expr = convert_from_reference (expr);
10537 /* Like tsubst, but deals with expressions. This function just replaces
10538 template parms; to finish processing the resultant expression, use
10542 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10544 enum tree_code code;
10547 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10550 code = TREE_CODE (t);
10555 r = retrieve_local_specialization (t);
10560 /* This can happen for a parameter name used later in a function
10561 declaration (such as in a late-specified return type). Just
10562 make a dummy decl, since it's only used for its type. */
10563 gcc_assert (cp_unevaluated_operand != 0);
10564 /* We copy T because want to tsubst the PARM_DECL only,
10565 not the following PARM_DECLs that are chained to T. */
10567 r = tsubst_decl (c, args, complain);
10568 /* Give it the template pattern as its context; its true context
10569 hasn't been instantiated yet and this is good enough for
10571 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10574 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10575 r = ARGUMENT_PACK_SELECT_ARG (r);
10584 if (DECL_TEMPLATE_PARM_P (t))
10585 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10586 /* There is no need to substitute into namespace-scope
10588 if (DECL_NAMESPACE_SCOPE_P (t))
10590 /* If ARGS is NULL, then T is known to be non-dependent. */
10591 if (args == NULL_TREE)
10592 return integral_constant_value (t);
10594 /* Unfortunately, we cannot just call lookup_name here.
10597 template <int I> int f() {
10599 struct S { void g() { E e = a; } };
10602 When we instantiate f<7>::S::g(), say, lookup_name is not
10603 clever enough to find f<7>::a. */
10605 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10606 /*entering_scope=*/0);
10608 for (v = TYPE_VALUES (enum_type);
10610 v = TREE_CHAIN (v))
10611 if (TREE_PURPOSE (v) == DECL_NAME (t))
10612 return TREE_VALUE (v);
10614 /* We didn't find the name. That should never happen; if
10615 name-lookup found it during preliminary parsing, we
10616 should find it again here during instantiation. */
10617 gcc_unreachable ();
10622 if (DECL_CONTEXT (t))
10626 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10627 /*entering_scope=*/1);
10628 if (ctx != DECL_CONTEXT (t))
10630 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10633 if (complain & tf_error)
10634 error ("using invalid field %qD", t);
10635 return error_mark_node;
10644 case FUNCTION_DECL:
10645 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10646 || local_variable_p (t))
10647 t = tsubst (t, args, complain, in_decl);
10652 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10654 case TEMPLATE_DECL:
10655 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10656 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10657 args, complain, in_decl);
10658 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10659 return tsubst (t, args, complain, in_decl);
10660 else if (DECL_CLASS_SCOPE_P (t)
10661 && uses_template_parms (DECL_CONTEXT (t)))
10663 /* Template template argument like the following example need
10666 template <template <class> class TT> struct C {};
10667 template <class T> struct D {
10668 template <class U> struct E {};
10673 We are processing the template argument `E' in #1 for
10674 the template instantiation #2. Originally, `E' is a
10675 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10676 have to substitute this with one having context `D<int>'. */
10678 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10679 return lookup_field (context, DECL_NAME(t), 0, false);
10682 /* Ordinary template template argument. */
10686 case REINTERPRET_CAST_EXPR:
10687 case CONST_CAST_EXPR:
10688 case STATIC_CAST_EXPR:
10689 case DYNAMIC_CAST_EXPR:
10692 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10693 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10696 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10698 /* We only want to compute the number of arguments. */
10699 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10700 complain, in_decl);
10703 if (TREE_CODE (expanded) == TREE_VEC)
10704 len = TREE_VEC_LENGTH (expanded);
10706 if (expanded == error_mark_node)
10707 return error_mark_node;
10708 else if (PACK_EXPANSION_P (expanded)
10709 || (TREE_CODE (expanded) == TREE_VEC
10711 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10713 if (TREE_CODE (expanded) == TREE_VEC)
10714 expanded = TREE_VEC_ELT (expanded, len - 1);
10716 if (TYPE_P (expanded))
10717 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10718 complain & tf_error);
10720 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10721 complain & tf_error);
10724 return build_int_cst (size_type_node, len);
10730 case TRUTH_NOT_EXPR:
10733 case UNARY_PLUS_EXPR: /* Unary + */
10738 case REALPART_EXPR:
10739 case IMAGPART_EXPR:
10741 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10742 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10744 case COMPONENT_REF:
10749 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10750 name = TREE_OPERAND (t, 1);
10751 if (TREE_CODE (name) == BIT_NOT_EXPR)
10753 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10754 complain, in_decl);
10755 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10757 else if (TREE_CODE (name) == SCOPE_REF
10758 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10760 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10761 complain, in_decl);
10762 name = TREE_OPERAND (name, 1);
10763 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10764 complain, in_decl);
10765 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10766 name = build_qualified_name (/*type=*/NULL_TREE,
10768 /*template_p=*/false);
10770 else if (TREE_CODE (name) == BASELINK)
10771 name = tsubst_baselink (name,
10772 non_reference (TREE_TYPE (object)),
10776 name = tsubst_copy (name, args, complain, in_decl);
10777 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10783 case TRUNC_DIV_EXPR:
10784 case CEIL_DIV_EXPR:
10785 case FLOOR_DIV_EXPR:
10786 case ROUND_DIV_EXPR:
10787 case EXACT_DIV_EXPR:
10791 case TRUNC_MOD_EXPR:
10792 case FLOOR_MOD_EXPR:
10793 case TRUTH_ANDIF_EXPR:
10794 case TRUTH_ORIF_EXPR:
10795 case TRUTH_AND_EXPR:
10796 case TRUTH_OR_EXPR:
10809 case COMPOUND_EXPR:
10812 case PREDECREMENT_EXPR:
10813 case PREINCREMENT_EXPR:
10814 case POSTDECREMENT_EXPR:
10815 case POSTINCREMENT_EXPR:
10817 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10818 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10821 return build_qualified_name (/*type=*/NULL_TREE,
10822 tsubst_copy (TREE_OPERAND (t, 0),
10823 args, complain, in_decl),
10824 tsubst_copy (TREE_OPERAND (t, 1),
10825 args, complain, in_decl),
10826 QUALIFIED_NAME_IS_TEMPLATE (t));
10831 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10832 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10833 NULL_TREE, NULL_TREE);
10837 int n = VL_EXP_OPERAND_LENGTH (t);
10838 tree result = build_vl_exp (CALL_EXPR, n);
10840 for (i = 0; i < n; i++)
10841 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10842 complain, in_decl);
10848 case PSEUDO_DTOR_EXPR:
10851 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10852 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10853 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10854 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10861 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10862 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10863 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10864 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10871 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10872 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10873 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10874 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10878 case TEMPLATE_ID_EXPR:
10880 /* Substituted template arguments */
10881 tree fn = TREE_OPERAND (t, 0);
10882 tree targs = TREE_OPERAND (t, 1);
10884 fn = tsubst_copy (fn, args, complain, in_decl);
10886 targs = tsubst_template_args (targs, args, complain, in_decl);
10888 return lookup_template_function (fn, targs);
10893 tree purpose, value, chain;
10895 if (t == void_list_node)
10898 purpose = TREE_PURPOSE (t);
10900 purpose = tsubst_copy (purpose, args, complain, in_decl);
10901 value = TREE_VALUE (t);
10903 value = tsubst_copy (value, args, complain, in_decl);
10904 chain = TREE_CHAIN (t);
10905 if (chain && chain != void_type_node)
10906 chain = tsubst_copy (chain, args, complain, in_decl);
10907 if (purpose == TREE_PURPOSE (t)
10908 && value == TREE_VALUE (t)
10909 && chain == TREE_CHAIN (t))
10911 return tree_cons (purpose, value, chain);
10916 case ENUMERAL_TYPE:
10918 case TEMPLATE_TYPE_PARM:
10919 case TEMPLATE_TEMPLATE_PARM:
10920 case BOUND_TEMPLATE_TEMPLATE_PARM:
10921 case TEMPLATE_PARM_INDEX:
10923 case REFERENCE_TYPE:
10925 case FUNCTION_TYPE:
10928 case TYPENAME_TYPE:
10929 case UNBOUND_CLASS_TEMPLATE:
10931 case DECLTYPE_TYPE:
10933 return tsubst (t, args, complain, in_decl);
10935 case IDENTIFIER_NODE:
10936 if (IDENTIFIER_TYPENAME_P (t))
10938 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10939 return mangle_conv_op_name_for_type (new_type);
10945 /* This is handled by tsubst_copy_and_build. */
10946 gcc_unreachable ();
10949 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10951 tsubst (TREE_TYPE (t), args, complain, in_decl));
10953 case CLEANUP_POINT_EXPR:
10954 /* We shouldn't have built any of these during initial template
10955 generation. Instead, they should be built during instantiation
10956 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10957 gcc_unreachable ();
10960 mark_used (TREE_OPERAND (t, 1));
10963 case EXPR_PACK_EXPANSION:
10964 error ("invalid use of pack expansion expression");
10965 return error_mark_node;
10967 case NONTYPE_ARGUMENT_PACK:
10968 error ("use %<...%> to expand argument pack");
10969 return error_mark_node;
10976 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10979 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10982 tree new_clauses = NULL, nc, oc;
10984 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10986 nc = copy_node (oc);
10987 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10990 switch (OMP_CLAUSE_CODE (nc))
10992 case OMP_CLAUSE_LASTPRIVATE:
10993 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10995 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10996 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10997 in_decl, /*integral_constant_expression_p=*/false);
10998 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10999 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11002 case OMP_CLAUSE_PRIVATE:
11003 case OMP_CLAUSE_SHARED:
11004 case OMP_CLAUSE_FIRSTPRIVATE:
11005 case OMP_CLAUSE_REDUCTION:
11006 case OMP_CLAUSE_COPYIN:
11007 case OMP_CLAUSE_COPYPRIVATE:
11008 case OMP_CLAUSE_IF:
11009 case OMP_CLAUSE_NUM_THREADS:
11010 case OMP_CLAUSE_SCHEDULE:
11011 case OMP_CLAUSE_COLLAPSE:
11012 OMP_CLAUSE_OPERAND (nc, 0)
11013 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11014 in_decl, /*integral_constant_expression_p=*/false);
11016 case OMP_CLAUSE_NOWAIT:
11017 case OMP_CLAUSE_ORDERED:
11018 case OMP_CLAUSE_DEFAULT:
11019 case OMP_CLAUSE_UNTIED:
11022 gcc_unreachable ();
11026 return finish_omp_clauses (nreverse (new_clauses));
11029 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11032 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11035 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11037 tree purpose, value, chain;
11042 if (TREE_CODE (t) != TREE_LIST)
11043 return tsubst_copy_and_build (t, args, complain, in_decl,
11044 /*function_p=*/false,
11045 /*integral_constant_expression_p=*/false);
11047 if (t == void_list_node)
11050 purpose = TREE_PURPOSE (t);
11052 purpose = RECUR (purpose);
11053 value = TREE_VALUE (t);
11054 if (value && TREE_CODE (value) != LABEL_DECL)
11055 value = RECUR (value);
11056 chain = TREE_CHAIN (t);
11057 if (chain && chain != void_type_node)
11058 chain = RECUR (chain);
11059 return tree_cons (purpose, value, chain);
11063 /* Substitute one OMP_FOR iterator. */
11066 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11067 tree condv, tree incrv, tree *clauses,
11068 tree args, tsubst_flags_t complain, tree in_decl,
11069 bool integral_constant_expression_p)
11071 #define RECUR(NODE) \
11072 tsubst_expr ((NODE), args, complain, in_decl, \
11073 integral_constant_expression_p)
11074 tree decl, init, cond, incr, auto_node;
11076 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11077 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11078 decl = RECUR (TREE_OPERAND (init, 0));
11079 init = TREE_OPERAND (init, 1);
11080 auto_node = type_uses_auto (TREE_TYPE (decl));
11081 if (auto_node && init)
11083 tree init_expr = init;
11084 if (TREE_CODE (init_expr) == DECL_EXPR)
11085 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11086 init_expr = RECUR (init_expr);
11088 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11090 gcc_assert (!type_dependent_expression_p (decl));
11092 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11094 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11095 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11096 if (TREE_CODE (incr) == MODIFY_EXPR)
11097 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11098 RECUR (TREE_OPERAND (incr, 1)),
11101 incr = RECUR (incr);
11102 TREE_VEC_ELT (declv, i) = decl;
11103 TREE_VEC_ELT (initv, i) = init;
11104 TREE_VEC_ELT (condv, i) = cond;
11105 TREE_VEC_ELT (incrv, i) = incr;
11109 if (init && TREE_CODE (init) != DECL_EXPR)
11112 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11114 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11115 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11116 && OMP_CLAUSE_DECL (c) == decl)
11118 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11119 && OMP_CLAUSE_DECL (c) == decl)
11120 error ("iteration variable %qD should not be firstprivate", decl);
11121 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11122 && OMP_CLAUSE_DECL (c) == decl)
11123 error ("iteration variable %qD should not be reduction", decl);
11127 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11128 OMP_CLAUSE_DECL (c) = decl;
11129 c = finish_omp_clauses (c);
11132 OMP_CLAUSE_CHAIN (c) = *clauses;
11137 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11138 if (COMPARISON_CLASS_P (cond))
11139 cond = build2 (TREE_CODE (cond), boolean_type_node,
11140 RECUR (TREE_OPERAND (cond, 0)),
11141 RECUR (TREE_OPERAND (cond, 1)));
11143 cond = RECUR (cond);
11144 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11145 switch (TREE_CODE (incr))
11147 case PREINCREMENT_EXPR:
11148 case PREDECREMENT_EXPR:
11149 case POSTINCREMENT_EXPR:
11150 case POSTDECREMENT_EXPR:
11151 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11152 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11155 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11156 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11158 tree rhs = TREE_OPERAND (incr, 1);
11159 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11160 RECUR (TREE_OPERAND (incr, 0)),
11161 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11162 RECUR (TREE_OPERAND (rhs, 0)),
11163 RECUR (TREE_OPERAND (rhs, 1))));
11166 incr = RECUR (incr);
11169 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11170 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11172 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11173 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11174 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11175 TREE_TYPE (decl), lhs,
11176 RECUR (TREE_OPERAND (incr, 2))));
11178 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11179 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11180 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11182 tree rhs = TREE_OPERAND (incr, 2);
11183 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11184 RECUR (TREE_OPERAND (incr, 0)),
11185 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11186 RECUR (TREE_OPERAND (rhs, 0)),
11187 RECUR (TREE_OPERAND (rhs, 1))));
11190 incr = RECUR (incr);
11193 incr = RECUR (incr);
11197 TREE_VEC_ELT (declv, i) = decl;
11198 TREE_VEC_ELT (initv, i) = init;
11199 TREE_VEC_ELT (condv, i) = cond;
11200 TREE_VEC_ELT (incrv, i) = incr;
11204 /* Like tsubst_copy for expressions, etc. but also does semantic
11208 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11209 bool integral_constant_expression_p)
11211 #define RECUR(NODE) \
11212 tsubst_expr ((NODE), args, complain, in_decl, \
11213 integral_constant_expression_p)
11217 if (t == NULL_TREE || t == error_mark_node)
11220 if (EXPR_HAS_LOCATION (t))
11221 input_location = EXPR_LOCATION (t);
11222 if (STATEMENT_CODE_P (TREE_CODE (t)))
11223 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11225 switch (TREE_CODE (t))
11227 case STATEMENT_LIST:
11229 tree_stmt_iterator i;
11230 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11231 RECUR (tsi_stmt (i));
11235 case CTOR_INITIALIZER:
11236 finish_mem_initializers (tsubst_initializer_list
11237 (TREE_OPERAND (t, 0), args));
11241 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11245 tmp = RECUR (EXPR_STMT_EXPR (t));
11246 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11247 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11249 finish_expr_stmt (tmp);
11253 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11261 decl = DECL_EXPR_DECL (t);
11262 if (TREE_CODE (decl) == LABEL_DECL)
11263 finish_label_decl (DECL_NAME (decl));
11264 else if (TREE_CODE (decl) == USING_DECL)
11266 tree scope = USING_DECL_SCOPE (decl);
11267 tree name = DECL_NAME (decl);
11270 scope = RECUR (scope);
11271 decl = lookup_qualified_name (scope, name,
11272 /*is_type_p=*/false,
11273 /*complain=*/false);
11274 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11275 qualified_name_lookup_error (scope, name, decl, input_location);
11277 do_local_using_decl (decl, scope, name);
11281 init = DECL_INITIAL (decl);
11282 decl = tsubst (decl, args, complain, in_decl);
11283 if (decl != error_mark_node)
11285 /* By marking the declaration as instantiated, we avoid
11286 trying to instantiate it. Since instantiate_decl can't
11287 handle local variables, and since we've already done
11288 all that needs to be done, that's the right thing to
11290 if (TREE_CODE (decl) == VAR_DECL)
11291 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11292 if (TREE_CODE (decl) == VAR_DECL
11293 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11294 /* Anonymous aggregates are a special case. */
11295 finish_anon_union (decl);
11298 maybe_push_decl (decl);
11299 if (TREE_CODE (decl) == VAR_DECL
11300 && DECL_PRETTY_FUNCTION_P (decl))
11302 /* For __PRETTY_FUNCTION__ we have to adjust the
11304 const char *const name
11305 = cxx_printable_name (current_function_decl, 2);
11306 init = cp_fname_init (name, &TREE_TYPE (decl));
11310 tree t = RECUR (init);
11313 /* If we had an initializer but it
11314 instantiated to nothing,
11315 value-initialize the object. This will
11316 only occur when the initializer was a
11317 pack expansion where the parameter packs
11318 used in that expansion were of length
11320 init = build_value_init (TREE_TYPE (decl));
11325 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11330 /* A DECL_EXPR can also be used as an expression, in the condition
11331 clause of an if/for/while construct. */
11336 stmt = begin_for_stmt ();
11337 RECUR (FOR_INIT_STMT (t));
11338 finish_for_init_stmt (stmt);
11339 tmp = RECUR (FOR_COND (t));
11340 finish_for_cond (tmp, stmt);
11341 tmp = RECUR (FOR_EXPR (t));
11342 finish_for_expr (tmp, stmt);
11343 RECUR (FOR_BODY (t));
11344 finish_for_stmt (stmt);
11348 stmt = begin_while_stmt ();
11349 tmp = RECUR (WHILE_COND (t));
11350 finish_while_stmt_cond (tmp, stmt);
11351 RECUR (WHILE_BODY (t));
11352 finish_while_stmt (stmt);
11356 stmt = begin_do_stmt ();
11357 RECUR (DO_BODY (t));
11358 finish_do_body (stmt);
11359 tmp = RECUR (DO_COND (t));
11360 finish_do_stmt (tmp, stmt);
11364 stmt = begin_if_stmt ();
11365 tmp = RECUR (IF_COND (t));
11366 finish_if_stmt_cond (tmp, stmt);
11367 RECUR (THEN_CLAUSE (t));
11368 finish_then_clause (stmt);
11370 if (ELSE_CLAUSE (t))
11372 begin_else_clause (stmt);
11373 RECUR (ELSE_CLAUSE (t));
11374 finish_else_clause (stmt);
11377 finish_if_stmt (stmt);
11381 if (BIND_EXPR_BODY_BLOCK (t))
11382 stmt = begin_function_body ();
11384 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11385 ? BCS_TRY_BLOCK : 0);
11387 RECUR (BIND_EXPR_BODY (t));
11389 if (BIND_EXPR_BODY_BLOCK (t))
11390 finish_function_body (stmt);
11392 finish_compound_stmt (stmt);
11396 finish_break_stmt ();
11399 case CONTINUE_STMT:
11400 finish_continue_stmt ();
11404 stmt = begin_switch_stmt ();
11405 tmp = RECUR (SWITCH_STMT_COND (t));
11406 finish_switch_cond (tmp, stmt);
11407 RECUR (SWITCH_STMT_BODY (t));
11408 finish_switch_stmt (stmt);
11411 case CASE_LABEL_EXPR:
11412 finish_case_label (EXPR_LOCATION (t),
11413 RECUR (CASE_LOW (t)),
11414 RECUR (CASE_HIGH (t)));
11419 tree decl = LABEL_EXPR_LABEL (t);
11422 label = finish_label_stmt (DECL_NAME (decl));
11423 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11424 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11429 tmp = GOTO_DESTINATION (t);
11430 if (TREE_CODE (tmp) != LABEL_DECL)
11431 /* Computed goto's must be tsubst'd into. On the other hand,
11432 non-computed gotos must not be; the identifier in question
11433 will have no binding. */
11436 tmp = DECL_NAME (tmp);
11437 finish_goto_stmt (tmp);
11441 tmp = finish_asm_stmt
11442 (ASM_VOLATILE_P (t),
11443 RECUR (ASM_STRING (t)),
11444 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11445 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11446 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11447 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11449 tree asm_expr = tmp;
11450 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11451 asm_expr = TREE_OPERAND (asm_expr, 0);
11452 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11459 stmt = begin_try_block ();
11460 RECUR (TRY_STMTS (t));
11461 finish_cleanup_try_block (stmt);
11462 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11466 tree compound_stmt = NULL_TREE;
11468 if (FN_TRY_BLOCK_P (t))
11469 stmt = begin_function_try_block (&compound_stmt);
11471 stmt = begin_try_block ();
11473 RECUR (TRY_STMTS (t));
11475 if (FN_TRY_BLOCK_P (t))
11476 finish_function_try_block (stmt);
11478 finish_try_block (stmt);
11480 RECUR (TRY_HANDLERS (t));
11481 if (FN_TRY_BLOCK_P (t))
11482 finish_function_handler_sequence (stmt, compound_stmt);
11484 finish_handler_sequence (stmt);
11490 tree decl = HANDLER_PARMS (t);
11494 decl = tsubst (decl, args, complain, in_decl);
11495 /* Prevent instantiate_decl from trying to instantiate
11496 this variable. We've already done all that needs to be
11498 if (decl != error_mark_node)
11499 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11501 stmt = begin_handler ();
11502 finish_handler_parms (decl, stmt);
11503 RECUR (HANDLER_BODY (t));
11504 finish_handler (stmt);
11509 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11512 case STATIC_ASSERT:
11515 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11518 /*integral_constant_expression_p=*/true);
11519 finish_static_assert (condition,
11520 STATIC_ASSERT_MESSAGE (t),
11521 STATIC_ASSERT_SOURCE_LOCATION (t),
11522 /*member_p=*/false);
11527 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11528 args, complain, in_decl);
11529 stmt = begin_omp_parallel ();
11530 RECUR (OMP_PARALLEL_BODY (t));
11531 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11532 = OMP_PARALLEL_COMBINED (t);
11536 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11537 args, complain, in_decl);
11538 stmt = begin_omp_task ();
11539 RECUR (OMP_TASK_BODY (t));
11540 finish_omp_task (tmp, stmt);
11545 tree clauses, body, pre_body;
11546 tree declv, initv, condv, incrv;
11549 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11550 args, complain, in_decl);
11551 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11552 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11553 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11554 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11556 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11557 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11558 &clauses, args, complain, in_decl,
11559 integral_constant_expression_p);
11561 stmt = begin_omp_structured_block ();
11563 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11564 if (TREE_VEC_ELT (initv, i) == NULL
11565 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11566 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11567 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11569 tree init = RECUR (TREE_VEC_ELT (initv, i));
11570 gcc_assert (init == TREE_VEC_ELT (declv, i));
11571 TREE_VEC_ELT (initv, i) = NULL_TREE;
11575 tree decl_expr = TREE_VEC_ELT (initv, i);
11576 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11577 gcc_assert (init != NULL);
11578 TREE_VEC_ELT (initv, i) = RECUR (init);
11579 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11581 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11584 pre_body = push_stmt_list ();
11585 RECUR (OMP_FOR_PRE_BODY (t));
11586 pre_body = pop_stmt_list (pre_body);
11588 body = push_stmt_list ();
11589 RECUR (OMP_FOR_BODY (t));
11590 body = pop_stmt_list (body);
11592 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11593 body, pre_body, clauses);
11595 add_stmt (finish_omp_structured_block (stmt));
11601 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11602 stmt = push_stmt_list ();
11603 RECUR (OMP_BODY (t));
11604 stmt = pop_stmt_list (stmt);
11607 OMP_BODY (t) = stmt;
11608 OMP_CLAUSES (t) = tmp;
11616 stmt = push_stmt_list ();
11617 RECUR (OMP_BODY (t));
11618 stmt = pop_stmt_list (stmt);
11621 OMP_BODY (t) = stmt;
11626 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11628 tree op1 = TREE_OPERAND (t, 1);
11629 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11630 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11631 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11635 case EXPR_PACK_EXPANSION:
11636 error ("invalid use of pack expansion expression");
11637 return error_mark_node;
11639 case NONTYPE_ARGUMENT_PACK:
11640 error ("use %<...%> to expand argument pack");
11641 return error_mark_node;
11644 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11646 return tsubst_copy_and_build (t, args, complain, in_decl,
11647 /*function_p=*/false,
11648 integral_constant_expression_p);
11655 /* T is a postfix-expression that is not being used in a function
11656 call. Return the substituted version of T. */
11659 tsubst_non_call_postfix_expression (tree t, tree args,
11660 tsubst_flags_t complain,
11663 if (TREE_CODE (t) == SCOPE_REF)
11664 t = tsubst_qualified_id (t, args, complain, in_decl,
11665 /*done=*/false, /*address_p=*/false);
11667 t = tsubst_copy_and_build (t, args, complain, in_decl,
11668 /*function_p=*/false,
11669 /*integral_constant_expression_p=*/false);
11674 /* Like tsubst but deals with expressions and performs semantic
11675 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11678 tsubst_copy_and_build (tree t,
11680 tsubst_flags_t complain,
11683 bool integral_constant_expression_p)
11685 #define RECUR(NODE) \
11686 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11687 /*function_p=*/false, \
11688 integral_constant_expression_p)
11692 if (t == NULL_TREE || t == error_mark_node)
11695 switch (TREE_CODE (t))
11699 /* Fall through. */
11700 case IDENTIFIER_NODE:
11704 bool non_integral_constant_expression_p;
11705 const char *error_msg;
11707 if (IDENTIFIER_TYPENAME_P (t))
11709 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11710 t = mangle_conv_op_name_for_type (new_type);
11713 /* Look up the name. */
11714 decl = lookup_name (t);
11716 /* By convention, expressions use ERROR_MARK_NODE to indicate
11717 failure, not NULL_TREE. */
11718 if (decl == NULL_TREE)
11719 decl = error_mark_node;
11721 decl = finish_id_expression (t, decl, NULL_TREE,
11723 integral_constant_expression_p,
11724 /*allow_non_integral_constant_expression_p=*/false,
11725 &non_integral_constant_expression_p,
11726 /*template_p=*/false,
11728 /*address_p=*/false,
11729 /*template_arg_p=*/false,
11734 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11735 decl = unqualified_name_lookup_error (decl);
11739 case TEMPLATE_ID_EXPR:
11742 tree templ = RECUR (TREE_OPERAND (t, 0));
11743 tree targs = TREE_OPERAND (t, 1);
11746 targs = tsubst_template_args (targs, args, complain, in_decl);
11748 if (TREE_CODE (templ) == COMPONENT_REF)
11750 object = TREE_OPERAND (templ, 0);
11751 templ = TREE_OPERAND (templ, 1);
11754 object = NULL_TREE;
11755 templ = lookup_template_function (templ, targs);
11758 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11759 object, templ, NULL_TREE);
11761 return baselink_for_fns (templ);
11766 tree r = RECUR (TREE_OPERAND (t, 0));
11768 if (REFERENCE_REF_P (t))
11770 /* A type conversion to reference type will be enclosed in
11771 such an indirect ref, but the substitution of the cast
11772 will have also added such an indirect ref. */
11773 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11774 r = convert_from_reference (r);
11777 r = build_x_indirect_ref (r, "unary *", complain);
11783 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11784 RECUR (TREE_OPERAND (t, 0)));
11787 case REINTERPRET_CAST_EXPR:
11788 case CONST_CAST_EXPR:
11789 case DYNAMIC_CAST_EXPR:
11790 case STATIC_CAST_EXPR:
11795 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11796 if (integral_constant_expression_p
11797 && !cast_valid_in_integral_constant_expression_p (type))
11799 if (complain & tf_error)
11800 error ("a cast to a type other than an integral or "
11801 "enumeration type cannot appear in a constant-expression");
11802 return error_mark_node;
11805 op = RECUR (TREE_OPERAND (t, 0));
11807 switch (TREE_CODE (t))
11810 return build_functional_cast (type, op, complain);
11811 case REINTERPRET_CAST_EXPR:
11812 return build_reinterpret_cast (type, op, complain);
11813 case CONST_CAST_EXPR:
11814 return build_const_cast (type, op, complain);
11815 case DYNAMIC_CAST_EXPR:
11816 return build_dynamic_cast (type, op, complain);
11817 case STATIC_CAST_EXPR:
11818 return build_static_cast (type, op, complain);
11820 gcc_unreachable ();
11824 case POSTDECREMENT_EXPR:
11825 case POSTINCREMENT_EXPR:
11826 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11827 args, complain, in_decl);
11828 return build_x_unary_op (TREE_CODE (t), op1, complain);
11830 case PREDECREMENT_EXPR:
11831 case PREINCREMENT_EXPR:
11835 case TRUTH_NOT_EXPR:
11836 case UNARY_PLUS_EXPR: /* Unary + */
11837 case REALPART_EXPR:
11838 case IMAGPART_EXPR:
11839 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11843 op1 = TREE_OPERAND (t, 0);
11844 if (TREE_CODE (op1) == SCOPE_REF)
11845 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11846 /*done=*/true, /*address_p=*/true);
11848 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11850 if (TREE_CODE (op1) == LABEL_DECL)
11851 return finish_label_address_expr (DECL_NAME (op1),
11852 EXPR_LOCATION (op1));
11853 return build_x_unary_op (ADDR_EXPR, op1, complain);
11858 case TRUNC_DIV_EXPR:
11859 case CEIL_DIV_EXPR:
11860 case FLOOR_DIV_EXPR:
11861 case ROUND_DIV_EXPR:
11862 case EXACT_DIV_EXPR:
11866 case TRUNC_MOD_EXPR:
11867 case FLOOR_MOD_EXPR:
11868 case TRUTH_ANDIF_EXPR:
11869 case TRUTH_ORIF_EXPR:
11870 case TRUTH_AND_EXPR:
11871 case TRUTH_OR_EXPR:
11886 return build_x_binary_op
11888 RECUR (TREE_OPERAND (t, 0)),
11889 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11891 : TREE_CODE (TREE_OPERAND (t, 0))),
11892 RECUR (TREE_OPERAND (t, 1)),
11893 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11895 : TREE_CODE (TREE_OPERAND (t, 1))),
11896 /*overloaded_p=*/NULL,
11900 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11901 /*address_p=*/false);
11903 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11904 args, complain, in_decl);
11905 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
11908 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11909 return tsubst_copy (t, args, complain, in_decl);
11913 op1 = TREE_OPERAND (t, 0);
11916 /* When there are no ARGS, we are trying to evaluate a
11917 non-dependent expression from the parser. Trying to do
11918 the substitutions may not work. */
11920 op1 = TREE_TYPE (op1);
11924 ++cp_unevaluated_operand;
11925 ++c_inhibit_evaluation_warnings;
11926 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11927 /*function_p=*/false,
11928 /*integral_constant_expression_p=*/false);
11929 --cp_unevaluated_operand;
11930 --c_inhibit_evaluation_warnings;
11933 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11934 complain & tf_error);
11936 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11937 complain & tf_error);
11941 tree r = build_x_modify_expr
11942 (RECUR (TREE_OPERAND (t, 0)),
11943 TREE_CODE (TREE_OPERAND (t, 1)),
11944 RECUR (TREE_OPERAND (t, 2)),
11946 /* TREE_NO_WARNING must be set if either the expression was
11947 parenthesized or it uses an operator such as >>= rather
11948 than plain assignment. In the former case, it was already
11949 set and must be copied. In the latter case,
11950 build_x_modify_expr sets it and it must not be reset
11952 if (TREE_NO_WARNING (t))
11953 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11958 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11959 args, complain, in_decl);
11960 /* Remember that there was a reference to this entity. */
11963 return build_x_arrow (op1);
11967 tree placement = RECUR (TREE_OPERAND (t, 0));
11968 tree init = RECUR (TREE_OPERAND (t, 3));
11969 VEC(tree,gc) *placement_vec;
11970 VEC(tree,gc) *init_vec;
11973 if (placement == NULL_TREE)
11974 placement_vec = NULL;
11977 placement_vec = make_tree_vector ();
11978 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
11979 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
11982 /* If there was an initializer in the original tree, but it
11983 instantiated to an empty list, then we should pass a
11984 non-NULL empty vector to tell build_new that it was an
11985 empty initializer() rather than no initializer. This can
11986 only happen when the initializer is a pack expansion whose
11987 parameter packs are of length zero. */
11988 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
11992 init_vec = make_tree_vector ();
11993 if (init == void_zero_node)
11994 gcc_assert (init_vec != NULL);
11997 for (; init != NULL_TREE; init = TREE_CHAIN (init))
11998 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12002 ret = build_new (&placement_vec,
12003 RECUR (TREE_OPERAND (t, 1)),
12004 RECUR (TREE_OPERAND (t, 2)),
12006 NEW_EXPR_USE_GLOBAL (t),
12009 if (placement_vec != NULL)
12010 release_tree_vector (placement_vec);
12011 if (init_vec != NULL)
12012 release_tree_vector (init_vec);
12018 return delete_sanity
12019 (RECUR (TREE_OPERAND (t, 0)),
12020 RECUR (TREE_OPERAND (t, 1)),
12021 DELETE_EXPR_USE_VEC (t),
12022 DELETE_EXPR_USE_GLOBAL (t));
12024 case COMPOUND_EXPR:
12025 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12026 RECUR (TREE_OPERAND (t, 1)),
12032 VEC(tree,gc) *call_args;
12033 unsigned int nargs, i;
12038 function = CALL_EXPR_FN (t);
12039 /* When we parsed the expression, we determined whether or
12040 not Koenig lookup should be performed. */
12041 koenig_p = KOENIG_LOOKUP_P (t);
12042 if (TREE_CODE (function) == SCOPE_REF)
12044 qualified_p = true;
12045 function = tsubst_qualified_id (function, args, complain, in_decl,
12047 /*address_p=*/false);
12051 if (TREE_CODE (function) == COMPONENT_REF)
12053 tree op = TREE_OPERAND (function, 1);
12055 qualified_p = (TREE_CODE (op) == SCOPE_REF
12056 || (BASELINK_P (op)
12057 && BASELINK_QUALIFIED_P (op)));
12060 qualified_p = false;
12062 function = tsubst_copy_and_build (function, args, complain,
12065 integral_constant_expression_p);
12067 if (BASELINK_P (function))
12068 qualified_p = true;
12071 nargs = call_expr_nargs (t);
12072 call_args = make_tree_vector ();
12073 for (i = 0; i < nargs; ++i)
12075 tree arg = CALL_EXPR_ARG (t, i);
12077 if (!PACK_EXPANSION_P (arg))
12078 VEC_safe_push (tree, gc, call_args,
12079 RECUR (CALL_EXPR_ARG (t, i)));
12082 /* Expand the pack expansion and push each entry onto
12084 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12085 if (TREE_CODE (arg) == TREE_VEC)
12087 unsigned int len, j;
12089 len = TREE_VEC_LENGTH (arg);
12090 for (j = 0; j < len; ++j)
12092 tree value = TREE_VEC_ELT (arg, j);
12093 if (value != NULL_TREE)
12094 value = convert_from_reference (value);
12095 VEC_safe_push (tree, gc, call_args, value);
12100 /* A partial substitution. Add one entry. */
12101 VEC_safe_push (tree, gc, call_args, arg);
12106 /* We do not perform argument-dependent lookup if normal
12107 lookup finds a non-function, in accordance with the
12108 expected resolution of DR 218. */
12110 && ((is_overloaded_fn (function)
12111 /* If lookup found a member function, the Koenig lookup is
12112 not appropriate, even if an unqualified-name was used
12113 to denote the function. */
12114 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12115 || TREE_CODE (function) == IDENTIFIER_NODE)
12116 /* Only do this when substitution turns a dependent call
12117 into a non-dependent call. */
12118 && type_dependent_expression_p_push (t)
12119 && !any_type_dependent_arguments_p (call_args))
12120 function = perform_koenig_lookup (function, call_args);
12122 if (TREE_CODE (function) == IDENTIFIER_NODE)
12124 unqualified_name_lookup_error (function);
12125 release_tree_vector (call_args);
12126 return error_mark_node;
12129 /* Remember that there was a reference to this entity. */
12130 if (DECL_P (function))
12131 mark_used (function);
12133 if (TREE_CODE (function) == OFFSET_REF)
12134 ret = build_offset_ref_call_from_tree (function, &call_args);
12135 else if (TREE_CODE (function) == COMPONENT_REF)
12137 if (!BASELINK_P (TREE_OPERAND (function, 1)))
12138 ret = finish_call_expr (function, &call_args,
12139 /*disallow_virtual=*/false,
12140 /*koenig_p=*/false,
12143 ret = (build_new_method_call
12144 (TREE_OPERAND (function, 0),
12145 TREE_OPERAND (function, 1),
12146 &call_args, NULL_TREE,
12147 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12152 ret = finish_call_expr (function, &call_args,
12153 /*disallow_virtual=*/qualified_p,
12157 release_tree_vector (call_args);
12163 return build_x_conditional_expr
12164 (RECUR (TREE_OPERAND (t, 0)),
12165 RECUR (TREE_OPERAND (t, 1)),
12166 RECUR (TREE_OPERAND (t, 2)),
12169 case PSEUDO_DTOR_EXPR:
12170 return finish_pseudo_destructor_expr
12171 (RECUR (TREE_OPERAND (t, 0)),
12172 RECUR (TREE_OPERAND (t, 1)),
12173 RECUR (TREE_OPERAND (t, 2)));
12177 tree purpose, value, chain;
12179 if (t == void_list_node)
12182 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12183 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12185 /* We have pack expansions, so expand those and
12186 create a new list out of it. */
12187 tree purposevec = NULL_TREE;
12188 tree valuevec = NULL_TREE;
12192 /* Expand the argument expressions. */
12193 if (TREE_PURPOSE (t))
12194 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12195 complain, in_decl);
12196 if (TREE_VALUE (t))
12197 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12198 complain, in_decl);
12200 /* Build the rest of the list. */
12201 chain = TREE_CHAIN (t);
12202 if (chain && chain != void_type_node)
12203 chain = RECUR (chain);
12205 /* Determine the number of arguments. */
12206 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12208 len = TREE_VEC_LENGTH (purposevec);
12209 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12211 else if (TREE_CODE (valuevec) == TREE_VEC)
12212 len = TREE_VEC_LENGTH (valuevec);
12215 /* Since we only performed a partial substitution into
12216 the argument pack, we only return a single list
12218 if (purposevec == TREE_PURPOSE (t)
12219 && valuevec == TREE_VALUE (t)
12220 && chain == TREE_CHAIN (t))
12223 return tree_cons (purposevec, valuevec, chain);
12226 /* Convert the argument vectors into a TREE_LIST */
12230 /* Grab the Ith values. */
12232 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12235 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12238 /* Build the list (backwards). */
12239 chain = tree_cons (purpose, value, chain);
12245 purpose = TREE_PURPOSE (t);
12247 purpose = RECUR (purpose);
12248 value = TREE_VALUE (t);
12250 value = RECUR (value);
12251 chain = TREE_CHAIN (t);
12252 if (chain && chain != void_type_node)
12253 chain = RECUR (chain);
12254 if (purpose == TREE_PURPOSE (t)
12255 && value == TREE_VALUE (t)
12256 && chain == TREE_CHAIN (t))
12258 return tree_cons (purpose, value, chain);
12261 case COMPONENT_REF:
12267 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12268 args, complain, in_decl);
12269 /* Remember that there was a reference to this entity. */
12270 if (DECL_P (object))
12271 mark_used (object);
12272 object_type = TREE_TYPE (object);
12274 member = TREE_OPERAND (t, 1);
12275 if (BASELINK_P (member))
12276 member = tsubst_baselink (member,
12277 non_reference (TREE_TYPE (object)),
12278 args, complain, in_decl);
12280 member = tsubst_copy (member, args, complain, in_decl);
12281 if (member == error_mark_node)
12282 return error_mark_node;
12284 if (object_type && !CLASS_TYPE_P (object_type))
12286 if (SCALAR_TYPE_P (object_type))
12288 tree s = NULL_TREE;
12289 tree dtor = member;
12291 if (TREE_CODE (dtor) == SCOPE_REF)
12293 s = TREE_OPERAND (dtor, 0);
12294 dtor = TREE_OPERAND (dtor, 1);
12296 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12298 dtor = TREE_OPERAND (dtor, 0);
12300 return finish_pseudo_destructor_expr (object, s, dtor);
12304 else if (TREE_CODE (member) == SCOPE_REF
12305 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12310 /* Lookup the template functions now that we know what the
12312 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12313 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12314 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12315 /*is_type_p=*/false,
12316 /*complain=*/false);
12317 if (BASELINK_P (member))
12319 BASELINK_FUNCTIONS (member)
12320 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12322 member = (adjust_result_of_qualified_name_lookup
12323 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12328 qualified_name_lookup_error (object_type, tmpl, member,
12330 return error_mark_node;
12333 else if (TREE_CODE (member) == SCOPE_REF
12334 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12335 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12337 if (complain & tf_error)
12339 if (TYPE_P (TREE_OPERAND (member, 0)))
12340 error ("%qT is not a class or namespace",
12341 TREE_OPERAND (member, 0));
12343 error ("%qD is not a class or namespace",
12344 TREE_OPERAND (member, 0));
12346 return error_mark_node;
12348 else if (TREE_CODE (member) == FIELD_DECL)
12349 return finish_non_static_data_member (member, object, NULL_TREE);
12351 return finish_class_member_access_expr (object, member,
12352 /*template_p=*/false,
12358 (RECUR (TREE_OPERAND (t, 0)));
12362 VEC(constructor_elt,gc) *n;
12363 constructor_elt *ce;
12364 unsigned HOST_WIDE_INT idx;
12365 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12366 bool process_index_p;
12368 bool need_copy_p = false;
12371 if (type == error_mark_node)
12372 return error_mark_node;
12374 /* digest_init will do the wrong thing if we let it. */
12375 if (type && TYPE_PTRMEMFUNC_P (type))
12378 /* We do not want to process the index of aggregate
12379 initializers as they are identifier nodes which will be
12380 looked up by digest_init. */
12381 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12383 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12384 newlen = VEC_length (constructor_elt, n);
12385 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12387 if (ce->index && process_index_p)
12388 ce->index = RECUR (ce->index);
12390 if (PACK_EXPANSION_P (ce->value))
12392 /* Substitute into the pack expansion. */
12393 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12396 if (ce->value == error_mark_node)
12398 else if (TREE_VEC_LENGTH (ce->value) == 1)
12399 /* Just move the argument into place. */
12400 ce->value = TREE_VEC_ELT (ce->value, 0);
12403 /* Update the length of the final CONSTRUCTOR
12404 arguments vector, and note that we will need to
12406 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12407 need_copy_p = true;
12411 ce->value = RECUR (ce->value);
12416 VEC(constructor_elt,gc) *old_n = n;
12418 n = VEC_alloc (constructor_elt, gc, newlen);
12419 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12422 if (TREE_CODE (ce->value) == TREE_VEC)
12424 int i, len = TREE_VEC_LENGTH (ce->value);
12425 for (i = 0; i < len; ++i)
12426 CONSTRUCTOR_APPEND_ELT (n, 0,
12427 TREE_VEC_ELT (ce->value, i));
12430 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12434 r = build_constructor (init_list_type_node, n);
12435 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12437 if (TREE_HAS_CONSTRUCTOR (t))
12438 return finish_compound_literal (type, r);
12445 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12446 if (TYPE_P (operand_0))
12447 return get_typeid (operand_0);
12448 return build_typeid (operand_0);
12458 tree r = tsubst_copy (t, args, complain, in_decl);
12460 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12461 /* If the original type was a reference, we'll be wrapped in
12462 the appropriate INDIRECT_REF. */
12463 r = convert_from_reference (r);
12468 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12469 tsubst_copy (TREE_TYPE (t), args, complain,
12472 case OFFSETOF_EXPR:
12473 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12477 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12478 complain, in_decl);
12480 tree type2 = TRAIT_EXPR_TYPE2 (t);
12482 type2 = tsubst_copy (type2, args, complain, in_decl);
12484 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12489 tree old_stmt_expr = cur_stmt_expr;
12490 tree stmt_expr = begin_stmt_expr ();
12492 cur_stmt_expr = stmt_expr;
12493 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12494 integral_constant_expression_p);
12495 stmt_expr = finish_stmt_expr (stmt_expr, false);
12496 cur_stmt_expr = old_stmt_expr;
12502 t = tsubst_copy (t, args, complain, in_decl);
12503 /* As in finish_id_expression, we resolve enumeration constants
12504 to their underlying values. */
12505 if (TREE_CODE (t) == CONST_DECL)
12507 used_types_insert (TREE_TYPE (t));
12508 return DECL_INITIAL (t);
12514 tree r = build_lambda_expr ();
12516 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12517 TREE_TYPE (r) = type;
12518 CLASSTYPE_LAMBDA_EXPR (type) = r;
12520 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12521 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12522 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12523 LAMBDA_EXPR_DISCRIMINATOR (r)
12524 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12525 LAMBDA_EXPR_CAPTURE_LIST (r)
12526 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12527 LAMBDA_EXPR_THIS_CAPTURE (r)
12528 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12529 LAMBDA_EXPR_EXTRA_SCOPE (r)
12530 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12532 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12533 determine_visibility (TYPE_NAME (type));
12534 /* Now that we know visibility, instantiate the type so we have a
12535 declaration of the op() for later calls to lambda_function. */
12536 complete_type (type);
12538 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12540 apply_lambda_return_type (r, type);
12542 return build_lambda_object (r);
12546 /* Handle Objective-C++ constructs, if appropriate. */
12549 = objcp_tsubst_copy_and_build (t, args, complain,
12550 in_decl, /*function_p=*/false);
12554 return tsubst_copy (t, args, complain, in_decl);
12560 /* Verify that the instantiated ARGS are valid. For type arguments,
12561 make sure that the type's linkage is ok. For non-type arguments,
12562 make sure they are constants if they are integral or enumerations.
12563 Emit an error under control of COMPLAIN, and return TRUE on error. */
12566 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12568 if (ARGUMENT_PACK_P (t))
12570 tree vec = ARGUMENT_PACK_ARGS (t);
12571 int len = TREE_VEC_LENGTH (vec);
12572 bool result = false;
12575 for (i = 0; i < len; ++i)
12576 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12580 else if (TYPE_P (t))
12582 /* [basic.link]: A name with no linkage (notably, the name
12583 of a class or enumeration declared in a local scope)
12584 shall not be used to declare an entity with linkage.
12585 This implies that names with no linkage cannot be used as
12588 DR 757 relaxes this restriction for C++0x. */
12589 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
12590 : no_linkage_check (t, /*relaxed_p=*/false));
12594 /* DR 488 makes use of a type with no linkage cause
12595 type deduction to fail. */
12596 if (complain & tf_error)
12598 if (TYPE_ANONYMOUS_P (nt))
12599 error ("%qT is/uses anonymous type", t);
12601 error ("template argument for %qD uses local type %qT",
12606 /* In order to avoid all sorts of complications, we do not
12607 allow variably-modified types as template arguments. */
12608 else if (variably_modified_type_p (t, NULL_TREE))
12610 if (complain & tf_error)
12611 error ("%qT is a variably modified type", t);
12615 /* A non-type argument of integral or enumerated type must be a
12617 else if (TREE_TYPE (t)
12618 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12619 && !TREE_CONSTANT (t))
12621 if (complain & tf_error)
12622 error ("integral expression %qE is not constant", t);
12629 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12631 int ix, len = DECL_NTPARMS (tmpl);
12632 bool result = false;
12634 for (ix = 0; ix != len; ix++)
12636 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12639 if (result && (complain & tf_error))
12640 error (" trying to instantiate %qD", tmpl);
12644 /* Instantiate the indicated variable or function template TMPL with
12645 the template arguments in TARG_PTR. */
12648 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12650 tree targ_ptr = orig_args;
12654 HOST_WIDE_INT saved_processing_template_decl;
12656 if (tmpl == error_mark_node)
12657 return error_mark_node;
12659 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12661 /* If this function is a clone, handle it specially. */
12662 if (DECL_CLONED_FUNCTION_P (tmpl))
12667 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12668 DECL_CLONED_FUNCTION. */
12669 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12670 targ_ptr, complain);
12671 if (spec == error_mark_node)
12672 return error_mark_node;
12674 /* Look for the clone. */
12675 FOR_EACH_CLONE (clone, spec)
12676 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12678 /* We should always have found the clone by now. */
12679 gcc_unreachable ();
12683 /* Check to see if we already have this specialization. */
12684 gen_tmpl = most_general_template (tmpl);
12685 if (tmpl != gen_tmpl)
12686 /* The TMPL is a partial instantiation. To get a full set of
12687 arguments we must add the arguments used to perform the
12688 partial instantiation. */
12689 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12692 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12693 but it doesn't seem to be on the hot path. */
12694 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12696 gcc_assert (tmpl == gen_tmpl
12697 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12699 || fndecl == NULL_TREE);
12701 if (spec != NULL_TREE)
12704 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12706 return error_mark_node;
12708 /* We are building a FUNCTION_DECL, during which the access of its
12709 parameters and return types have to be checked. However this
12710 FUNCTION_DECL which is the desired context for access checking
12711 is not built yet. We solve this chicken-and-egg problem by
12712 deferring all checks until we have the FUNCTION_DECL. */
12713 push_deferring_access_checks (dk_deferred);
12715 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12716 (because, for example, we have encountered a non-dependent
12717 function call in the body of a template function and must now
12718 determine which of several overloaded functions will be called),
12719 within the instantiation itself we are not processing a
12721 saved_processing_template_decl = processing_template_decl;
12722 processing_template_decl = 0;
12723 /* Substitute template parameters to obtain the specialization. */
12724 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12725 targ_ptr, complain, gen_tmpl);
12726 processing_template_decl = saved_processing_template_decl;
12727 if (fndecl == error_mark_node)
12728 return error_mark_node;
12730 /* Now we know the specialization, compute access previously
12732 push_access_scope (fndecl);
12734 /* Some typedefs referenced from within the template code need to be access
12735 checked at template instantiation time, i.e now. These types were
12736 added to the template at parsing time. Let's get those and perfom
12737 the acces checks then. */
12738 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12739 perform_deferred_access_checks ();
12740 pop_access_scope (fndecl);
12741 pop_deferring_access_checks ();
12743 /* The DECL_TI_TEMPLATE should always be the immediate parent
12744 template, not the most general template. */
12745 DECL_TI_TEMPLATE (fndecl) = tmpl;
12747 /* If we've just instantiated the main entry point for a function,
12748 instantiate all the alternate entry points as well. We do this
12749 by cloning the instantiation of the main entry point, not by
12750 instantiating the template clones. */
12751 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12752 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12757 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12758 NARGS elements of the arguments that are being used when calling
12759 it. TARGS is a vector into which the deduced template arguments
12762 Return zero for success, 2 for an incomplete match that doesn't resolve
12763 all the types, and 1 for complete failure. An error message will be
12764 printed only for an incomplete match.
12766 If FN is a conversion operator, or we are trying to produce a specific
12767 specialization, RETURN_TYPE is the return type desired.
12769 The EXPLICIT_TARGS are explicit template arguments provided via a
12772 The parameter STRICT is one of:
12775 We are deducing arguments for a function call, as in
12776 [temp.deduct.call].
12779 We are deducing arguments for a conversion function, as in
12780 [temp.deduct.conv].
12783 We are deducing arguments when doing an explicit instantiation
12784 as in [temp.explicit], when determining an explicit specialization
12785 as in [temp.expl.spec], or when taking the address of a function
12786 template, as in [temp.deduct.funcaddr]. */
12789 fn_type_unification (tree fn,
12790 tree explicit_targs,
12793 unsigned int nargs,
12795 unification_kind_t strict,
12801 bool incomplete_argument_packs_p = false;
12803 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
12805 fntype = TREE_TYPE (fn);
12806 if (explicit_targs)
12810 The specified template arguments must match the template
12811 parameters in kind (i.e., type, nontype, template), and there
12812 must not be more arguments than there are parameters;
12813 otherwise type deduction fails.
12815 Nontype arguments must match the types of the corresponding
12816 nontype template parameters, or must be convertible to the
12817 types of the corresponding nontype parameters as specified in
12818 _temp.arg.nontype_, otherwise type deduction fails.
12820 All references in the function type of the function template
12821 to the corresponding template parameters are replaced by the
12822 specified template argument values. If a substitution in a
12823 template parameter or in the function type of the function
12824 template results in an invalid type, type deduction fails. */
12825 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
12826 int i, len = TREE_VEC_LENGTH (tparms);
12827 tree converted_args;
12828 bool incomplete = false;
12830 if (explicit_targs == error_mark_node)
12834 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
12835 /*require_all_args=*/false,
12836 /*use_default_args=*/false));
12837 if (converted_args == error_mark_node)
12840 /* Substitute the explicit args into the function type. This is
12841 necessary so that, for instance, explicitly declared function
12842 arguments can match null pointed constants. If we were given
12843 an incomplete set of explicit args, we must not do semantic
12844 processing during substitution as we could create partial
12846 for (i = 0; i < len; i++)
12848 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12849 bool parameter_pack = false;
12851 /* Dig out the actual parm. */
12852 if (TREE_CODE (parm) == TYPE_DECL
12853 || TREE_CODE (parm) == TEMPLATE_DECL)
12855 parm = TREE_TYPE (parm);
12856 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
12858 else if (TREE_CODE (parm) == PARM_DECL)
12860 parm = DECL_INITIAL (parm);
12861 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
12864 if (parameter_pack)
12868 template_parm_level_and_index (parm, &level, &idx);
12870 /* Mark the argument pack as "incomplete". We could
12871 still deduce more arguments during unification. */
12872 targ = TMPL_ARG (converted_args, level, idx);
12875 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
12876 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
12877 = ARGUMENT_PACK_ARGS (targ);
12880 /* We have some incomplete argument packs. */
12881 incomplete_argument_packs_p = true;
12885 if (incomplete_argument_packs_p)
12886 /* Any substitution is guaranteed to be incomplete if there
12887 are incomplete argument packs, because we can still deduce
12891 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
12893 processing_template_decl += incomplete;
12894 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
12895 processing_template_decl -= incomplete;
12897 if (fntype == error_mark_node)
12900 /* Place the explicitly specified arguments in TARGS. */
12901 for (i = NUM_TMPL_ARGS (converted_args); i--;)
12902 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12905 /* Never do unification on the 'this' parameter. */
12906 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12912 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12913 new_args = XALLOCAVEC (tree, nargs + 1);
12914 new_args[0] = return_type;
12915 memcpy (new_args + 1, args, nargs * sizeof (tree));
12920 /* We allow incomplete unification without an error message here
12921 because the standard doesn't seem to explicitly prohibit it. Our
12922 callers must be ready to deal with unification failures in any
12924 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12925 targs, parms, args, nargs, /*subr=*/0,
12928 if (result == 0 && incomplete_argument_packs_p)
12930 int i, len = NUM_TMPL_ARGS (targs);
12932 /* Clear the "incomplete" flags on all argument packs. */
12933 for (i = 0; i < len; i++)
12935 tree arg = TREE_VEC_ELT (targs, i);
12936 if (ARGUMENT_PACK_P (arg))
12938 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12939 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12944 /* Now that we have bindings for all of the template arguments,
12945 ensure that the arguments deduced for the template template
12946 parameters have compatible template parameter lists. We cannot
12947 check this property before we have deduced all template
12948 arguments, because the template parameter types of a template
12949 template parameter might depend on prior template parameters
12950 deduced after the template template parameter. The following
12951 ill-formed example illustrates this issue:
12953 template<typename T, template<T> class C> void f(C<5>, T);
12955 template<int N> struct X {};
12958 f(X<5>(), 5l); // error: template argument deduction fails
12961 The template parameter list of 'C' depends on the template type
12962 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12963 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12964 time that we deduce 'C'. */
12966 && !template_template_parm_bindings_ok_p
12967 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12971 /* All is well so far. Now, check:
12975 When all template arguments have been deduced, all uses of
12976 template parameters in nondeduced contexts are replaced with
12977 the corresponding deduced argument values. If the
12978 substitution results in an invalid type, as described above,
12979 type deduction fails. */
12981 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
12982 if (substed == error_mark_node)
12985 /* If we're looking for an exact match, check that what we got
12986 is indeed an exact match. It might not be if some template
12987 parameters are used in non-deduced contexts. */
12988 if (strict == DEDUCE_EXACT)
12993 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
12995 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
12996 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
12997 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13005 /* Adjust types before performing type deduction, as described in
13006 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
13007 sections are symmetric. PARM is the type of a function parameter
13008 or the return type of the conversion function. ARG is the type of
13009 the argument passed to the call, or the type of the value
13010 initialized with the result of the conversion function.
13011 ARG_EXPR is the original argument expression, which may be null. */
13014 maybe_adjust_types_for_deduction (unification_kind_t strict,
13028 /* Swap PARM and ARG throughout the remainder of this
13029 function; the handling is precisely symmetric since PARM
13030 will initialize ARG rather than vice versa. */
13038 /* Core issue #873: Do the DR606 thing (see below) for these cases,
13039 too, but here handle it by stripping the reference from PARM
13040 rather than by adding it to ARG. */
13041 if (TREE_CODE (*parm) == REFERENCE_TYPE
13042 && TYPE_REF_IS_RVALUE (*parm)
13043 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13044 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13045 && TREE_CODE (*arg) == REFERENCE_TYPE
13046 && !TYPE_REF_IS_RVALUE (*arg))
13047 *parm = TREE_TYPE (*parm);
13048 /* Nothing else to do in this case. */
13052 gcc_unreachable ();
13055 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13057 /* [temp.deduct.call]
13059 If P is not a reference type:
13061 --If A is an array type, the pointer type produced by the
13062 array-to-pointer standard conversion (_conv.array_) is
13063 used in place of A for type deduction; otherwise,
13065 --If A is a function type, the pointer type produced by
13066 the function-to-pointer standard conversion
13067 (_conv.func_) is used in place of A for type deduction;
13070 --If A is a cv-qualified type, the top level
13071 cv-qualifiers of A's type are ignored for type
13073 if (TREE_CODE (*arg) == ARRAY_TYPE)
13074 *arg = build_pointer_type (TREE_TYPE (*arg));
13075 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13076 *arg = build_pointer_type (*arg);
13078 *arg = TYPE_MAIN_VARIANT (*arg);
13081 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13082 of the form T&&, where T is a template parameter, and the argument
13083 is an lvalue, T is deduced as A& */
13084 if (TREE_CODE (*parm) == REFERENCE_TYPE
13085 && TYPE_REF_IS_RVALUE (*parm)
13086 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13087 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13088 && arg_expr && real_lvalue_p (arg_expr))
13089 *arg = build_reference_type (*arg);
13091 /* [temp.deduct.call]
13093 If P is a cv-qualified type, the top level cv-qualifiers
13094 of P's type are ignored for type deduction. If P is a
13095 reference type, the type referred to by P is used for
13097 *parm = TYPE_MAIN_VARIANT (*parm);
13098 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13100 *parm = TREE_TYPE (*parm);
13101 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13104 /* DR 322. For conversion deduction, remove a reference type on parm
13105 too (which has been swapped into ARG). */
13106 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13107 *arg = TREE_TYPE (*arg);
13112 /* Most parms like fn_type_unification.
13114 If SUBR is 1, we're being called recursively (to unify the
13115 arguments of a function or method parameter of a function
13119 type_unification_real (tree tparms,
13123 unsigned int xnargs,
13125 unification_kind_t strict,
13128 tree parm, arg, arg_expr;
13130 int ntparms = TREE_VEC_LENGTH (tparms);
13132 int saw_undeduced = 0;
13135 unsigned int nargs;
13138 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13139 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13140 gcc_assert (ntparms > 0);
13145 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13146 | UNIFY_ALLOW_DERIVED);
13150 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13154 sub_strict = UNIFY_ALLOW_NONE;
13158 gcc_unreachable ();
13167 while (parms && parms != void_list_node
13170 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13173 parm = TREE_VALUE (parms);
13174 parms = TREE_CHAIN (parms);
13179 if (arg == error_mark_node)
13181 if (arg == unknown_type_node)
13182 /* We can't deduce anything from this, but we might get all the
13183 template args from other function args. */
13186 /* Conversions will be performed on a function argument that
13187 corresponds with a function parameter that contains only
13188 non-deducible template parameters and explicitly specified
13189 template parameters. */
13190 if (!uses_template_parms (parm))
13195 type = TREE_TYPE (arg);
13199 if (same_type_p (parm, type))
13201 if (strict != DEDUCE_EXACT
13202 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13211 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13212 if (type_unknown_p (arg))
13214 /* [temp.deduct.type]
13216 A template-argument can be deduced from a pointer to
13217 function or pointer to member function argument if
13218 the set of overloaded functions does not contain
13219 function templates and at most one of a set of
13220 overloaded functions provides a unique match. */
13221 if (resolve_overloaded_unification
13222 (tparms, targs, parm, arg, strict, sub_strict))
13228 arg = unlowered_expr_type (arg);
13229 if (arg == error_mark_node)
13234 int arg_strict = sub_strict;
13237 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13240 if (arg == init_list_type_node && arg_expr)
13242 if (unify (tparms, targs, parm, arg, arg_strict))
13249 && parms != void_list_node
13250 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13252 /* Unify the remaining arguments with the pack expansion type. */
13254 tree parmvec = make_tree_vec (1);
13256 /* Allocate a TREE_VEC and copy in all of the arguments */
13257 argvec = make_tree_vec (nargs - ia);
13258 for (i = 0; ia < nargs; ++ia, ++i)
13259 TREE_VEC_ELT (argvec, i) = args[ia];
13261 /* Copy the parameter into parmvec. */
13262 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13263 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13264 /*call_args_p=*/true, /*subr=*/subr))
13267 /* Advance to the end of the list of parameters. */
13268 parms = TREE_CHAIN (parms);
13271 /* Fail if we've reached the end of the parm list, and more args
13272 are present, and the parm list isn't variadic. */
13273 if (ia < nargs && parms == void_list_node)
13275 /* Fail if parms are left and they don't have default values. */
13276 if (parms && parms != void_list_node
13277 && TREE_PURPOSE (parms) == NULL_TREE)
13281 for (i = 0; i < ntparms; i++)
13282 if (!TREE_VEC_ELT (targs, i))
13286 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13289 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13291 /* If this is an undeduced nontype parameter that depends on
13292 a type parameter, try another pass; its type may have been
13293 deduced from a later argument than the one from which
13294 this parameter can be deduced. */
13295 if (TREE_CODE (tparm) == PARM_DECL
13296 && uses_template_parms (TREE_TYPE (tparm))
13297 && !saw_undeduced++)
13300 /* Core issue #226 (C++0x) [temp.deduct]:
13302 If a template argument has not been deduced, its
13303 default template argument, if any, is used.
13305 When we are in C++98 mode, TREE_PURPOSE will either
13306 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13307 to explicitly check cxx_dialect here. */
13308 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13310 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13311 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13312 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13313 arg = convert_template_argument (parm, arg, targs, tf_none,
13315 if (arg == error_mark_node)
13319 TREE_VEC_ELT (targs, i) = arg;
13324 /* If the type parameter is a parameter pack, then it will
13325 be deduced to an empty parameter pack. */
13326 if (template_parameter_pack_p (tparm))
13330 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13332 arg = make_node (NONTYPE_ARGUMENT_PACK);
13333 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13334 TREE_CONSTANT (arg) = 1;
13337 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13339 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13341 TREE_VEC_ELT (targs, i) = arg;
13351 /* Subroutine of type_unification_real. Args are like the variables
13352 at the call site. ARG is an overloaded function (or template-id);
13353 we try deducing template args from each of the overloads, and if
13354 only one succeeds, we go with that. Modifies TARGS and returns
13355 true on success. */
13358 resolve_overloaded_unification (tree tparms,
13362 unification_kind_t strict,
13365 tree tempargs = copy_node (targs);
13367 tree goodfn = NULL_TREE;
13370 if (TREE_CODE (arg) == ADDR_EXPR)
13372 arg = TREE_OPERAND (arg, 0);
13378 if (TREE_CODE (arg) == COMPONENT_REF)
13379 /* Handle `&x' where `x' is some static or non-static member
13381 arg = TREE_OPERAND (arg, 1);
13383 if (TREE_CODE (arg) == OFFSET_REF)
13384 arg = TREE_OPERAND (arg, 1);
13386 /* Strip baselink information. */
13387 if (BASELINK_P (arg))
13388 arg = BASELINK_FUNCTIONS (arg);
13390 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13392 /* If we got some explicit template args, we need to plug them into
13393 the affected templates before we try to unify, in case the
13394 explicit args will completely resolve the templates in question. */
13396 tree expl_subargs = TREE_OPERAND (arg, 1);
13397 arg = TREE_OPERAND (arg, 0);
13399 for (; arg; arg = OVL_NEXT (arg))
13401 tree fn = OVL_CURRENT (arg);
13402 tree subargs, elem;
13404 if (TREE_CODE (fn) != TEMPLATE_DECL)
13407 ++processing_template_decl;
13408 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13409 expl_subargs, /*check_ret=*/false);
13412 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13413 if (try_one_overload (tparms, targs, tempargs, parm,
13414 elem, strict, sub_strict, addr_p)
13415 && (!goodfn || !decls_match (goodfn, elem)))
13421 --processing_template_decl;
13424 else if (TREE_CODE (arg) != OVERLOAD
13425 && TREE_CODE (arg) != FUNCTION_DECL)
13426 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13427 -- but the deduction does not succeed because the expression is
13428 not just the function on its own. */
13431 for (; arg; arg = OVL_NEXT (arg))
13432 if (try_one_overload (tparms, targs, tempargs, parm,
13433 TREE_TYPE (OVL_CURRENT (arg)),
13434 strict, sub_strict, addr_p)
13435 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13437 goodfn = OVL_CURRENT (arg);
13441 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13442 to function or pointer to member function argument if the set of
13443 overloaded functions does not contain function templates and at most
13444 one of a set of overloaded functions provides a unique match.
13446 So if we found multiple possibilities, we return success but don't
13447 deduce anything. */
13451 int i = TREE_VEC_LENGTH (targs);
13453 if (TREE_VEC_ELT (tempargs, i))
13454 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13462 /* Core DR 115: In contexts where deduction is done and fails, or in
13463 contexts where deduction is not done, if a template argument list is
13464 specified and it, along with any default template arguments, identifies
13465 a single function template specialization, then the template-id is an
13466 lvalue for the function template specialization. */
13469 resolve_nondeduced_context (tree orig_expr)
13471 tree expr, offset, baselink;
13474 if (!type_unknown_p (orig_expr))
13479 offset = NULL_TREE;
13480 baselink = NULL_TREE;
13482 if (TREE_CODE (expr) == ADDR_EXPR)
13484 expr = TREE_OPERAND (expr, 0);
13487 if (TREE_CODE (expr) == OFFSET_REF)
13490 expr = TREE_OPERAND (expr, 1);
13492 if (TREE_CODE (expr) == BASELINK)
13495 expr = BASELINK_FUNCTIONS (expr);
13498 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13501 tree goodfn = NULL_TREE;
13503 /* If we got some explicit template args, we need to plug them into
13504 the affected templates before we try to unify, in case the
13505 explicit args will completely resolve the templates in question. */
13507 tree expl_subargs = TREE_OPERAND (expr, 1);
13508 tree arg = TREE_OPERAND (expr, 0);
13509 tree badfn = NULL_TREE;
13510 tree badargs = NULL_TREE;
13512 for (; arg; arg = OVL_NEXT (arg))
13514 tree fn = OVL_CURRENT (arg);
13515 tree subargs, elem;
13517 if (TREE_CODE (fn) != TEMPLATE_DECL)
13520 ++processing_template_decl;
13521 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13522 expl_subargs, /*check_ret=*/false);
13523 if (subargs && !any_dependent_template_arguments_p (subargs))
13525 elem = instantiate_template (fn, subargs, tf_none);
13526 if (elem == error_mark_node)
13531 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13537 --processing_template_decl;
13543 expr = build_baselink (BASELINK_BINFO (baselink),
13544 BASELINK_ACCESS_BINFO (baselink),
13545 expr, BASELINK_OPTYPE (baselink));
13547 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13548 TREE_OPERAND (offset, 0), expr);
13550 expr = build_address (expr);
13553 else if (good == 0 && badargs)
13554 /* There were no good options and at least one bad one, so let the
13555 user know what the problem is. */
13556 instantiate_template (badfn, badargs, tf_warning_or_error);
13561 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13562 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13563 different overloads deduce different arguments for a given parm.
13564 ADDR_P is true if the expression for which deduction is being
13565 performed was of the form "& fn" rather than simply "fn".
13567 Returns 1 on success. */
13570 try_one_overload (tree tparms,
13575 unification_kind_t strict,
13583 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13584 to function or pointer to member function argument if the set of
13585 overloaded functions does not contain function templates and at most
13586 one of a set of overloaded functions provides a unique match.
13588 So if this is a template, just return success. */
13590 if (uses_template_parms (arg))
13593 if (TREE_CODE (arg) == METHOD_TYPE)
13594 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13596 arg = build_pointer_type (arg);
13598 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13600 /* We don't copy orig_targs for this because if we have already deduced
13601 some template args from previous args, unify would complain when we
13602 try to deduce a template parameter for the same argument, even though
13603 there isn't really a conflict. */
13604 nargs = TREE_VEC_LENGTH (targs);
13605 tempargs = make_tree_vec (nargs);
13607 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13610 /* First make sure we didn't deduce anything that conflicts with
13611 explicitly specified args. */
13612 for (i = nargs; i--; )
13614 tree elt = TREE_VEC_ELT (tempargs, i);
13615 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13619 else if (uses_template_parms (elt))
13620 /* Since we're unifying against ourselves, we will fill in
13621 template args used in the function parm list with our own
13622 template parms. Discard them. */
13623 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13624 else if (oldelt && !template_args_equal (oldelt, elt))
13628 for (i = nargs; i--; )
13630 tree elt = TREE_VEC_ELT (tempargs, i);
13633 TREE_VEC_ELT (targs, i) = elt;
13639 /* PARM is a template class (perhaps with unbound template
13640 parameters). ARG is a fully instantiated type. If ARG can be
13641 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13642 TARGS are as for unify. */
13645 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13647 tree copy_of_targs;
13649 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13650 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13651 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13654 /* We need to make a new template argument vector for the call to
13655 unify. If we used TARGS, we'd clutter it up with the result of
13656 the attempted unification, even if this class didn't work out.
13657 We also don't want to commit ourselves to all the unifications
13658 we've already done, since unification is supposed to be done on
13659 an argument-by-argument basis. In other words, consider the
13660 following pathological case:
13662 template <int I, int J, int K>
13665 template <int I, int J>
13666 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13668 template <int I, int J, int K>
13669 void f(S<I, J, K>, S<I, I, I>);
13678 Now, by the time we consider the unification involving `s2', we
13679 already know that we must have `f<0, 0, 0>'. But, even though
13680 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13681 because there are two ways to unify base classes of S<0, 1, 2>
13682 with S<I, I, I>. If we kept the already deduced knowledge, we
13683 would reject the possibility I=1. */
13684 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13686 /* If unification failed, we're done. */
13687 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13688 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13694 /* Given a template type PARM and a class type ARG, find the unique
13695 base type in ARG that is an instance of PARM. We do not examine
13696 ARG itself; only its base-classes. If there is not exactly one
13697 appropriate base class, return NULL_TREE. PARM may be the type of
13698 a partial specialization, as well as a plain template type. Used
13702 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13704 tree rval = NULL_TREE;
13707 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13709 binfo = TYPE_BINFO (complete_type (arg));
13711 /* The type could not be completed. */
13714 /* Walk in inheritance graph order. The search order is not
13715 important, and this avoids multiple walks of virtual bases. */
13716 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13718 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13722 /* If there is more than one satisfactory baseclass, then:
13726 If they yield more than one possible deduced A, the type
13730 if (rval && !same_type_p (r, rval))
13740 /* Returns the level of DECL, which declares a template parameter. */
13743 template_decl_level (tree decl)
13745 switch (TREE_CODE (decl))
13748 case TEMPLATE_DECL:
13749 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13752 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13755 gcc_unreachable ();
13760 /* Decide whether ARG can be unified with PARM, considering only the
13761 cv-qualifiers of each type, given STRICT as documented for unify.
13762 Returns nonzero iff the unification is OK on that basis. */
13765 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13767 int arg_quals = cp_type_quals (arg);
13768 int parm_quals = cp_type_quals (parm);
13770 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13771 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13773 /* Although a CVR qualifier is ignored when being applied to a
13774 substituted template parameter ([8.3.2]/1 for example), that
13775 does not apply during deduction [14.8.2.4]/1, (even though
13776 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13777 this). Except when we're allowing additional CV qualifiers
13778 at the outer level [14.8.2.1]/3,1st bullet. */
13779 if ((TREE_CODE (arg) == REFERENCE_TYPE
13780 || TREE_CODE (arg) == FUNCTION_TYPE
13781 || TREE_CODE (arg) == METHOD_TYPE)
13782 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
13785 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
13786 && (parm_quals & TYPE_QUAL_RESTRICT))
13790 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13791 && (arg_quals & parm_quals) != parm_quals)
13794 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
13795 && (parm_quals & arg_quals) != arg_quals)
13801 /* Determines the LEVEL and INDEX for the template parameter PARM. */
13803 template_parm_level_and_index (tree parm, int* level, int* index)
13805 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13806 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13807 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13809 *index = TEMPLATE_TYPE_IDX (parm);
13810 *level = TEMPLATE_TYPE_LEVEL (parm);
13814 *index = TEMPLATE_PARM_IDX (parm);
13815 *level = TEMPLATE_PARM_LEVEL (parm);
13819 /* Unifies the remaining arguments in PACKED_ARGS with the pack
13820 expansion at the end of PACKED_PARMS. Returns 0 if the type
13821 deduction succeeds, 1 otherwise. STRICT is the same as in
13822 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
13823 call argument list. We'll need to adjust the arguments to make them
13824 types. SUBR tells us if this is from a recursive call to
13825 type_unification_real. */
13827 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
13828 tree packed_args, int strict, bool call_args_p,
13832 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
13833 tree pattern = PACK_EXPANSION_PATTERN (parm);
13834 tree pack, packs = NULL_TREE;
13835 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
13836 int len = TREE_VEC_LENGTH (packed_args);
13838 /* Determine the parameter packs we will be deducing from the
13839 pattern, and record their current deductions. */
13840 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
13841 pack; pack = TREE_CHAIN (pack))
13843 tree parm_pack = TREE_VALUE (pack);
13846 /* Determine the index and level of this parameter pack. */
13847 template_parm_level_and_index (parm_pack, &level, &idx);
13849 /* Keep track of the parameter packs and their corresponding
13851 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
13852 TREE_TYPE (packs) = make_tree_vec (len - start);
13855 /* Loop through all of the arguments that have not yet been
13856 unified and unify each with the pattern. */
13857 for (i = start; i < len; i++)
13859 tree parm = pattern;
13861 /* For each parameter pack, clear out the deduced value so that
13862 we can deduce it again. */
13863 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13866 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13868 TMPL_ARG (targs, level, idx) = NULL_TREE;
13871 /* Unify the pattern with the current argument. */
13873 tree arg = TREE_VEC_ELT (packed_args, i);
13874 tree arg_expr = NULL_TREE;
13875 int arg_strict = strict;
13876 bool skip_arg_p = false;
13882 /* This mirrors what we do in type_unification_real. */
13886 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
13887 | UNIFY_ALLOW_MORE_CV_QUAL
13888 | UNIFY_ALLOW_DERIVED);
13892 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13896 sub_strict = UNIFY_ALLOW_NONE;
13900 gcc_unreachable ();
13905 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13906 if (type_unknown_p (arg))
13908 /* [temp.deduct.type] A template-argument can be
13909 deduced from a pointer to function or pointer
13910 to member function argument if the set of
13911 overloaded functions does not contain function
13912 templates and at most one of a set of
13913 overloaded functions provides a unique
13916 if (resolve_overloaded_unification
13917 (tparms, targs, parm, arg,
13918 (unification_kind_t) strict,
13928 arg = unlowered_expr_type (arg);
13929 if (arg == error_mark_node)
13934 arg_strict = sub_strict;
13938 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
13939 &parm, &arg, arg_expr);
13944 if (unify (tparms, targs, parm, arg, arg_strict))
13949 /* For each parameter pack, collect the deduced value. */
13950 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13953 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13955 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
13956 TMPL_ARG (targs, level, idx);
13960 /* Verify that the results of unification with the parameter packs
13961 produce results consistent with what we've seen before, and make
13962 the deduced argument packs available. */
13963 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13965 tree old_pack = TREE_VALUE (pack);
13966 tree new_args = TREE_TYPE (pack);
13967 int i, len = TREE_VEC_LENGTH (new_args);
13968 bool nondeduced_p = false;
13970 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
13971 actually deduce anything. */
13972 for (i = 0; i < len && !nondeduced_p; ++i)
13973 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
13974 nondeduced_p = true;
13978 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
13980 /* Prepend the explicit arguments onto NEW_ARGS. */
13981 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13982 tree old_args = new_args;
13983 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
13984 int len = explicit_len + TREE_VEC_LENGTH (old_args);
13986 /* Copy the explicit arguments. */
13987 new_args = make_tree_vec (len);
13988 for (i = 0; i < explicit_len; i++)
13989 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
13991 /* Copy the deduced arguments. */
13992 for (; i < len; i++)
13993 TREE_VEC_ELT (new_args, i) =
13994 TREE_VEC_ELT (old_args, i - explicit_len);
14002 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14004 /* Build the deduced *_ARGUMENT_PACK. */
14005 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
14007 result = make_node (NONTYPE_ARGUMENT_PACK);
14008 TREE_TYPE (result) =
14009 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
14010 TREE_CONSTANT (result) = 1;
14013 result = cxx_make_type (TYPE_ARGUMENT_PACK);
14015 SET_ARGUMENT_PACK_ARGS (result, new_args);
14017 /* Note the deduced argument packs for this parameter
14019 TMPL_ARG (targs, level, idx) = result;
14021 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
14022 && (ARGUMENT_PACK_ARGS (old_pack)
14023 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
14025 /* We only had the explicitly-provided arguments before, but
14026 now we have a complete set of arguments. */
14028 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14029 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14031 /* Keep the original deduced argument pack. */
14032 TMPL_ARG (targs, level, idx) = old_pack;
14034 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
14035 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
14036 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
14038 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
14040 /* Inconsistent unification of this parameter pack. */
14046 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14048 /* Keep the original deduced argument pack. */
14049 TMPL_ARG (targs, level, idx) = old_pack;
14056 /* Deduce the value of template parameters. TPARMS is the (innermost)
14057 set of template parameters to a template. TARGS is the bindings
14058 for those template parameters, as determined thus far; TARGS may
14059 include template arguments for outer levels of template parameters
14060 as well. PARM is a parameter to a template function, or a
14061 subcomponent of that parameter; ARG is the corresponding argument.
14062 This function attempts to match PARM with ARG in a manner
14063 consistent with the existing assignments in TARGS. If more values
14064 are deduced, then TARGS is updated.
14066 Returns 0 if the type deduction succeeds, 1 otherwise. The
14067 parameter STRICT is a bitwise or of the following flags:
14070 Require an exact match between PARM and ARG.
14071 UNIFY_ALLOW_MORE_CV_QUAL:
14072 Allow the deduced ARG to be more cv-qualified (by qualification
14073 conversion) than ARG.
14074 UNIFY_ALLOW_LESS_CV_QUAL:
14075 Allow the deduced ARG to be less cv-qualified than ARG.
14076 UNIFY_ALLOW_DERIVED:
14077 Allow the deduced ARG to be a template base class of ARG,
14078 or a pointer to a template base class of the type pointed to by
14080 UNIFY_ALLOW_INTEGER:
14081 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14082 case for more information.
14083 UNIFY_ALLOW_OUTER_LEVEL:
14084 This is the outermost level of a deduction. Used to determine validity
14085 of qualification conversions. A valid qualification conversion must
14086 have const qualified pointers leading up to the inner type which
14087 requires additional CV quals, except at the outer level, where const
14088 is not required [conv.qual]. It would be normal to set this flag in
14089 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14090 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14091 This is the outermost level of a deduction, and PARM can be more CV
14092 qualified at this point.
14093 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14094 This is the outermost level of a deduction, and PARM can be less CV
14095 qualified at this point. */
14098 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14103 int strict_in = strict;
14105 /* I don't think this will do the right thing with respect to types.
14106 But the only case I've seen it in so far has been array bounds, where
14107 signedness is the only information lost, and I think that will be
14109 while (TREE_CODE (parm) == NOP_EXPR)
14110 parm = TREE_OPERAND (parm, 0);
14112 if (arg == error_mark_node)
14114 if (arg == unknown_type_node
14115 || arg == init_list_type_node)
14116 /* We can't deduce anything from this, but we might get all the
14117 template args from other function args. */
14120 /* If PARM uses template parameters, then we can't bail out here,
14121 even if ARG == PARM, since we won't record unifications for the
14122 template parameters. We might need them if we're trying to
14123 figure out which of two things is more specialized. */
14124 if (arg == parm && !uses_template_parms (parm))
14127 /* Handle init lists early, so the rest of the function can assume
14128 we're dealing with a type. */
14129 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14133 tree orig_parm = parm;
14135 /* Replace T with std::initializer_list<T> for deduction. */
14136 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14137 && flag_deduce_init_list)
14138 parm = listify (parm);
14140 if (!is_std_init_list (parm))
14141 /* We can only deduce from an initializer list argument if the
14142 parameter is std::initializer_list; otherwise this is a
14143 non-deduced context. */
14146 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14148 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14150 int elt_strict = strict;
14151 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14153 tree type = TREE_TYPE (elt);
14154 /* It should only be possible to get here for a call. */
14155 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14156 elt_strict |= maybe_adjust_types_for_deduction
14157 (DEDUCE_CALL, &elttype, &type, elt);
14161 if (unify (tparms, targs, elttype, elt, elt_strict))
14165 /* If the std::initializer_list<T> deduction worked, replace the
14166 deduced A with std::initializer_list<A>. */
14167 if (orig_parm != parm)
14169 idx = TEMPLATE_TYPE_IDX (orig_parm);
14170 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14171 targ = listify (targ);
14172 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14177 /* Immediately reject some pairs that won't unify because of
14178 cv-qualification mismatches. */
14179 if (TREE_CODE (arg) == TREE_CODE (parm)
14181 /* It is the elements of the array which hold the cv quals of an array
14182 type, and the elements might be template type parms. We'll check
14183 when we recurse. */
14184 && TREE_CODE (arg) != ARRAY_TYPE
14185 /* We check the cv-qualifiers when unifying with template type
14186 parameters below. We want to allow ARG `const T' to unify with
14187 PARM `T' for example, when computing which of two templates
14188 is more specialized, for example. */
14189 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14190 && !check_cv_quals_for_unify (strict_in, arg, parm))
14193 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14194 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14195 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14196 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14197 strict &= ~UNIFY_ALLOW_DERIVED;
14198 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14199 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14201 switch (TREE_CODE (parm))
14203 case TYPENAME_TYPE:
14205 case UNBOUND_CLASS_TEMPLATE:
14206 /* In a type which contains a nested-name-specifier, template
14207 argument values cannot be deduced for template parameters used
14208 within the nested-name-specifier. */
14211 case TEMPLATE_TYPE_PARM:
14212 case TEMPLATE_TEMPLATE_PARM:
14213 case BOUND_TEMPLATE_TEMPLATE_PARM:
14214 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14215 if (tparm == error_mark_node)
14218 if (TEMPLATE_TYPE_LEVEL (parm)
14219 != template_decl_level (tparm))
14220 /* The PARM is not one we're trying to unify. Just check
14221 to see if it matches ARG. */
14222 return (TREE_CODE (arg) == TREE_CODE (parm)
14223 && same_type_p (parm, arg)) ? 0 : 1;
14224 idx = TEMPLATE_TYPE_IDX (parm);
14225 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14226 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14228 /* Check for mixed types and values. */
14229 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14230 && TREE_CODE (tparm) != TYPE_DECL)
14231 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14232 && TREE_CODE (tparm) != TEMPLATE_DECL))
14235 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14237 /* ARG must be constructed from a template class or a template
14238 template parameter. */
14239 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14240 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14244 tree parmvec = TYPE_TI_ARGS (parm);
14245 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14247 = DECL_INNERMOST_TEMPLATE_PARMS
14248 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14250 int parm_variadic_p = 0;
14252 /* The resolution to DR150 makes clear that default
14253 arguments for an N-argument may not be used to bind T
14254 to a template template parameter with fewer than N
14255 parameters. It is not safe to permit the binding of
14256 default arguments as an extension, as that may change
14257 the meaning of a conforming program. Consider:
14259 struct Dense { static const unsigned int dim = 1; };
14261 template <template <typename> class View,
14263 void operator+(float, View<Block> const&);
14265 template <typename Block,
14266 unsigned int Dim = Block::dim>
14267 struct Lvalue_proxy { operator float() const; };
14271 Lvalue_proxy<Dense> p;
14276 Here, if Lvalue_proxy is permitted to bind to View, then
14277 the global operator+ will be used; if they are not, the
14278 Lvalue_proxy will be converted to float. */
14279 if (coerce_template_parms (parm_parms,
14281 TYPE_TI_TEMPLATE (parm),
14283 /*require_all_args=*/true,
14284 /*use_default_args=*/false)
14285 == error_mark_node)
14288 /* Deduce arguments T, i from TT<T> or TT<i>.
14289 We check each element of PARMVEC and ARGVEC individually
14290 rather than the whole TREE_VEC since they can have
14291 different number of elements. */
14293 parmvec = expand_template_argument_pack (parmvec);
14294 argvec = expand_template_argument_pack (argvec);
14296 len = TREE_VEC_LENGTH (parmvec);
14298 /* Check if the parameters end in a pack, making them
14301 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14302 parm_variadic_p = 1;
14304 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14307 for (i = 0; i < len - parm_variadic_p; ++i)
14309 if (unify (tparms, targs,
14310 TREE_VEC_ELT (parmvec, i),
14311 TREE_VEC_ELT (argvec, i),
14316 if (parm_variadic_p
14317 && unify_pack_expansion (tparms, targs,
14320 /*call_args_p=*/false,
14324 arg = TYPE_TI_TEMPLATE (arg);
14326 /* Fall through to deduce template name. */
14329 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14330 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14332 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14334 /* Simple cases: Value already set, does match or doesn't. */
14335 if (targ != NULL_TREE && template_args_equal (targ, arg))
14342 /* If PARM is `const T' and ARG is only `int', we don't have
14343 a match unless we are allowing additional qualification.
14344 If ARG is `const int' and PARM is just `T' that's OK;
14345 that binds `const int' to `T'. */
14346 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14350 /* Consider the case where ARG is `const volatile int' and
14351 PARM is `const T'. Then, T should be `volatile int'. */
14352 arg = cp_build_qualified_type_real
14353 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14354 if (arg == error_mark_node)
14357 /* Simple cases: Value already set, does match or doesn't. */
14358 if (targ != NULL_TREE && same_type_p (targ, arg))
14363 /* Make sure that ARG is not a variable-sized array. (Note
14364 that were talking about variable-sized arrays (like
14365 `int[n]'), rather than arrays of unknown size (like
14366 `int[]').) We'll get very confused by such a type since
14367 the bound of the array will not be computable in an
14368 instantiation. Besides, such types are not allowed in
14369 ISO C++, so we can do as we please here. */
14370 if (variably_modified_type_p (arg, NULL_TREE))
14373 /* Strip typedefs as in convert_template_argument. */
14374 arg = strip_typedefs (arg);
14377 /* If ARG is a parameter pack or an expansion, we cannot unify
14378 against it unless PARM is also a parameter pack. */
14379 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14380 && !template_parameter_pack_p (parm))
14383 /* If the argument deduction results is a METHOD_TYPE,
14384 then there is a problem.
14385 METHOD_TYPE doesn't map to any real C++ type the result of
14386 the deduction can not be of that type. */
14387 if (TREE_CODE (arg) == METHOD_TYPE)
14390 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14393 case TEMPLATE_PARM_INDEX:
14394 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14395 if (tparm == error_mark_node)
14398 if (TEMPLATE_PARM_LEVEL (parm)
14399 != template_decl_level (tparm))
14400 /* The PARM is not one we're trying to unify. Just check
14401 to see if it matches ARG. */
14402 return !(TREE_CODE (arg) == TREE_CODE (parm)
14403 && cp_tree_equal (parm, arg));
14405 idx = TEMPLATE_PARM_IDX (parm);
14406 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14409 return !cp_tree_equal (targ, arg);
14411 /* [temp.deduct.type] If, in the declaration of a function template
14412 with a non-type template-parameter, the non-type
14413 template-parameter is used in an expression in the function
14414 parameter-list and, if the corresponding template-argument is
14415 deduced, the template-argument type shall match the type of the
14416 template-parameter exactly, except that a template-argument
14417 deduced from an array bound may be of any integral type.
14418 The non-type parameter might use already deduced type parameters. */
14419 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14420 if (!TREE_TYPE (arg))
14421 /* Template-parameter dependent expression. Just accept it for now.
14422 It will later be processed in convert_template_argument. */
14424 else if (same_type_p (TREE_TYPE (arg), tparm))
14426 else if ((strict & UNIFY_ALLOW_INTEGER)
14427 && (TREE_CODE (tparm) == INTEGER_TYPE
14428 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14429 /* Convert the ARG to the type of PARM; the deduced non-type
14430 template argument must exactly match the types of the
14431 corresponding parameter. */
14432 arg = fold (build_nop (tparm, arg));
14433 else if (uses_template_parms (tparm))
14434 /* We haven't deduced the type of this parameter yet. Try again
14440 /* If ARG is a parameter pack or an expansion, we cannot unify
14441 against it unless PARM is also a parameter pack. */
14442 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14443 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14446 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14451 /* A pointer-to-member constant can be unified only with
14452 another constant. */
14453 if (TREE_CODE (arg) != PTRMEM_CST)
14456 /* Just unify the class member. It would be useless (and possibly
14457 wrong, depending on the strict flags) to unify also
14458 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14459 arg refer to the same variable, even if through different
14460 classes. For instance:
14462 struct A { int x; };
14465 Unification of &A::x and &B::x must succeed. */
14466 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14467 PTRMEM_CST_MEMBER (arg), strict);
14472 if (TREE_CODE (arg) != POINTER_TYPE)
14475 /* [temp.deduct.call]
14477 A can be another pointer or pointer to member type that can
14478 be converted to the deduced A via a qualification
14479 conversion (_conv.qual_).
14481 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14482 This will allow for additional cv-qualification of the
14483 pointed-to types if appropriate. */
14485 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14486 /* The derived-to-base conversion only persists through one
14487 level of pointers. */
14488 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14490 return unify (tparms, targs, TREE_TYPE (parm),
14491 TREE_TYPE (arg), strict);
14494 case REFERENCE_TYPE:
14495 if (TREE_CODE (arg) != REFERENCE_TYPE)
14497 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14498 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14501 if (TREE_CODE (arg) != ARRAY_TYPE)
14503 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14504 != (TYPE_DOMAIN (arg) == NULL_TREE))
14506 if (TYPE_DOMAIN (parm) != NULL_TREE)
14513 /* Our representation of array types uses "N - 1" as the
14514 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14515 not an integer constant. We cannot unify arbitrarily
14516 complex expressions, so we eliminate the MINUS_EXPRs
14518 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14519 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14522 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14523 parm_max = TREE_OPERAND (parm_max, 0);
14525 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14526 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14529 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14530 trying to unify the type of a variable with the type
14531 of a template parameter. For example:
14533 template <unsigned int N>
14534 void f (char (&) [N]);
14541 Here, the type of the ARG will be "int [g(i)]", and
14542 may be a SAVE_EXPR, etc. */
14543 if (TREE_CODE (arg_max) != MINUS_EXPR)
14545 arg_max = TREE_OPERAND (arg_max, 0);
14548 /* If only one of the bounds used a MINUS_EXPR, compensate
14549 by adding one to the other bound. */
14550 if (parm_cst && !arg_cst)
14551 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14555 else if (arg_cst && !parm_cst)
14556 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14561 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14564 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14565 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14572 case ENUMERAL_TYPE:
14574 if (TREE_CODE (arg) != TREE_CODE (parm))
14577 /* We have already checked cv-qualification at the top of the
14579 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14582 /* As far as unification is concerned, this wins. Later checks
14583 will invalidate it if necessary. */
14586 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14587 /* Type INTEGER_CST can come from ordinary constant template args. */
14589 while (TREE_CODE (arg) == NOP_EXPR)
14590 arg = TREE_OPERAND (arg, 0);
14592 if (TREE_CODE (arg) != INTEGER_CST)
14594 return !tree_int_cst_equal (parm, arg);
14599 if (TREE_CODE (arg) != TREE_VEC)
14601 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14603 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14604 if (unify (tparms, targs,
14605 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14613 if (TREE_CODE (arg) != TREE_CODE (parm))
14616 if (TYPE_PTRMEMFUNC_P (parm))
14618 if (!TYPE_PTRMEMFUNC_P (arg))
14621 return unify (tparms, targs,
14622 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14623 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14627 if (CLASSTYPE_TEMPLATE_INFO (parm))
14629 tree t = NULL_TREE;
14631 if (strict_in & UNIFY_ALLOW_DERIVED)
14633 /* First, we try to unify the PARM and ARG directly. */
14634 t = try_class_unification (tparms, targs,
14639 /* Fallback to the special case allowed in
14640 [temp.deduct.call]:
14642 If P is a class, and P has the form
14643 template-id, then A can be a derived class of
14644 the deduced A. Likewise, if P is a pointer to
14645 a class of the form template-id, A can be a
14646 pointer to a derived class pointed to by the
14648 t = get_template_base (tparms, targs, parm, arg);
14654 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14655 && (CLASSTYPE_TI_TEMPLATE (parm)
14656 == CLASSTYPE_TI_TEMPLATE (arg)))
14657 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14658 Then, we should unify `int' and `U'. */
14661 /* There's no chance of unification succeeding. */
14664 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14665 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14667 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14672 case FUNCTION_TYPE:
14674 unsigned int nargs;
14679 if (TREE_CODE (arg) != TREE_CODE (parm))
14682 /* CV qualifications for methods can never be deduced, they must
14683 match exactly. We need to check them explicitly here,
14684 because type_unification_real treats them as any other
14685 cv-qualified parameter. */
14686 if (TREE_CODE (parm) == METHOD_TYPE
14687 && (!check_cv_quals_for_unify
14689 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14690 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14693 if (unify (tparms, targs, TREE_TYPE (parm),
14694 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14697 nargs = list_length (TYPE_ARG_TYPES (arg));
14698 args = XALLOCAVEC (tree, nargs);
14699 for (a = TYPE_ARG_TYPES (arg), i = 0;
14700 a != NULL_TREE && a != void_list_node;
14701 a = TREE_CHAIN (a), ++i)
14702 args[i] = TREE_VALUE (a);
14705 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14706 args, nargs, 1, DEDUCE_EXACT,
14711 /* Unify a pointer to member with a pointer to member function, which
14712 deduces the type of the member as a function type. */
14713 if (TYPE_PTRMEMFUNC_P (arg))
14717 cp_cv_quals cv_quals;
14719 /* Check top-level cv qualifiers */
14720 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14723 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14724 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14727 /* Determine the type of the function we are unifying against. */
14728 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14730 build_function_type (TREE_TYPE (method_type),
14731 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14733 /* Extract the cv-qualifiers of the member function from the
14734 implicit object parameter and place them on the function
14735 type to be restored later. */
14737 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14738 fntype = build_qualified_type (fntype, cv_quals);
14739 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14742 if (TREE_CODE (arg) != OFFSET_TYPE)
14744 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14745 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14747 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14751 if (DECL_TEMPLATE_PARM_P (parm))
14752 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14753 if (arg != integral_constant_value (parm))
14758 case TEMPLATE_DECL:
14759 /* Matched cases are handled by the ARG == PARM test above. */
14762 case TYPE_ARGUMENT_PACK:
14763 case NONTYPE_ARGUMENT_PACK:
14765 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14766 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14767 int i, len = TREE_VEC_LENGTH (packed_parms);
14768 int argslen = TREE_VEC_LENGTH (packed_args);
14769 int parm_variadic_p = 0;
14771 for (i = 0; i < len; ++i)
14773 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14776 /* We can unify against something with a trailing
14778 parm_variadic_p = 1;
14780 /* Since there is something following the pack
14781 expansion, we cannot unify this template argument
14788 /* If we don't have enough arguments to satisfy the parameters
14789 (not counting the pack expression at the end), or we have
14790 too many arguments for a parameter list that doesn't end in
14791 a pack expression, we can't unify. */
14792 if (argslen < (len - parm_variadic_p)
14793 || (argslen > len && !parm_variadic_p))
14796 /* Unify all of the parameters that precede the (optional)
14797 pack expression. */
14798 for (i = 0; i < len - parm_variadic_p; ++i)
14800 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
14801 TREE_VEC_ELT (packed_args, i), strict))
14805 if (parm_variadic_p)
14806 return unify_pack_expansion (tparms, targs,
14807 packed_parms, packed_args,
14808 strict, /*call_args_p=*/false,
14816 case DECLTYPE_TYPE:
14817 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
14822 /* Unification fails if we hit an error node. */
14826 gcc_assert (EXPR_P (parm));
14828 /* We must be looking at an expression. This can happen with
14832 void foo(S<I>, S<I + 2>);
14834 This is a "nondeduced context":
14838 The nondeduced contexts are:
14840 --A type that is a template-id in which one or more of
14841 the template-arguments is an expression that references
14842 a template-parameter.
14844 In these cases, we assume deduction succeeded, but don't
14845 actually infer any unifications. */
14847 if (!uses_template_parms (parm)
14848 && !template_args_equal (parm, arg))
14855 /* Note that DECL can be defined in this translation unit, if
14859 mark_definable (tree decl)
14862 DECL_NOT_REALLY_EXTERN (decl) = 1;
14863 FOR_EACH_CLONE (clone, decl)
14864 DECL_NOT_REALLY_EXTERN (clone) = 1;
14867 /* Called if RESULT is explicitly instantiated, or is a member of an
14868 explicitly instantiated class. */
14871 mark_decl_instantiated (tree result, int extern_p)
14873 SET_DECL_EXPLICIT_INSTANTIATION (result);
14875 /* If this entity has already been written out, it's too late to
14876 make any modifications. */
14877 if (TREE_ASM_WRITTEN (result))
14880 if (TREE_CODE (result) != FUNCTION_DECL)
14881 /* The TREE_PUBLIC flag for function declarations will have been
14882 set correctly by tsubst. */
14883 TREE_PUBLIC (result) = 1;
14885 /* This might have been set by an earlier implicit instantiation. */
14886 DECL_COMDAT (result) = 0;
14889 DECL_NOT_REALLY_EXTERN (result) = 0;
14892 mark_definable (result);
14893 /* Always make artificials weak. */
14894 if (DECL_ARTIFICIAL (result) && flag_weak)
14895 comdat_linkage (result);
14896 /* For WIN32 we also want to put explicit instantiations in
14897 linkonce sections. */
14898 else if (TREE_PUBLIC (result))
14899 maybe_make_one_only (result);
14902 /* If EXTERN_P, then this function will not be emitted -- unless
14903 followed by an explicit instantiation, at which point its linkage
14904 will be adjusted. If !EXTERN_P, then this function will be
14905 emitted here. In neither circumstance do we want
14906 import_export_decl to adjust the linkage. */
14907 DECL_INTERFACE_KNOWN (result) = 1;
14910 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
14911 important template arguments. If any are missing, we check whether
14912 they're important by using error_mark_node for substituting into any
14913 args that were used for partial ordering (the ones between ARGS and END)
14914 and seeing if it bubbles up. */
14917 check_undeduced_parms (tree targs, tree args, tree end)
14919 bool found = false;
14921 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
14922 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
14925 TREE_VEC_ELT (targs, i) = error_mark_node;
14929 for (; args != end; args = TREE_CHAIN (args))
14931 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
14932 if (substed == error_mark_node)
14939 /* Given two function templates PAT1 and PAT2, return:
14941 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
14942 -1 if PAT2 is more specialized than PAT1.
14943 0 if neither is more specialized.
14945 LEN indicates the number of parameters we should consider
14946 (defaulted parameters should not be considered).
14948 The 1998 std underspecified function template partial ordering, and
14949 DR214 addresses the issue. We take pairs of arguments, one from
14950 each of the templates, and deduce them against each other. One of
14951 the templates will be more specialized if all the *other*
14952 template's arguments deduce against its arguments and at least one
14953 of its arguments *does* *not* deduce against the other template's
14954 corresponding argument. Deduction is done as for class templates.
14955 The arguments used in deduction have reference and top level cv
14956 qualifiers removed. Iff both arguments were originally reference
14957 types *and* deduction succeeds in both directions, the template
14958 with the more cv-qualified argument wins for that pairing (if
14959 neither is more cv-qualified, they both are equal). Unlike regular
14960 deduction, after all the arguments have been deduced in this way,
14961 we do *not* verify the deduced template argument values can be
14962 substituted into non-deduced contexts.
14964 The logic can be a bit confusing here, because we look at deduce1 and
14965 targs1 to see if pat2 is at least as specialized, and vice versa; if we
14966 can find template arguments for pat1 to make arg1 look like arg2, that
14967 means that arg2 is at least as specialized as arg1. */
14970 more_specialized_fn (tree pat1, tree pat2, int len)
14972 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
14973 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
14974 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
14975 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
14976 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
14977 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
14978 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
14979 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
14980 tree origs1, origs2;
14981 bool lose1 = false;
14982 bool lose2 = false;
14984 /* Remove the this parameter from non-static member functions. If
14985 one is a non-static member function and the other is not a static
14986 member function, remove the first parameter from that function
14987 also. This situation occurs for operator functions where we
14988 locate both a member function (with this pointer) and non-member
14989 operator (with explicit first operand). */
14990 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
14992 len--; /* LEN is the number of significant arguments for DECL1 */
14993 args1 = TREE_CHAIN (args1);
14994 if (!DECL_STATIC_FUNCTION_P (decl2))
14995 args2 = TREE_CHAIN (args2);
14997 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
14999 args2 = TREE_CHAIN (args2);
15000 if (!DECL_STATIC_FUNCTION_P (decl1))
15003 args1 = TREE_CHAIN (args1);
15007 /* If only one is a conversion operator, they are unordered. */
15008 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
15011 /* Consider the return type for a conversion function */
15012 if (DECL_CONV_FN_P (decl1))
15014 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
15015 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
15019 processing_template_decl++;
15025 /* Stop when an ellipsis is seen. */
15026 && args1 != NULL_TREE && args2 != NULL_TREE)
15028 tree arg1 = TREE_VALUE (args1);
15029 tree arg2 = TREE_VALUE (args2);
15030 int deduce1, deduce2;
15034 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15035 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15037 /* When both arguments are pack expansions, we need only
15038 unify the patterns themselves. */
15039 arg1 = PACK_EXPANSION_PATTERN (arg1);
15040 arg2 = PACK_EXPANSION_PATTERN (arg2);
15042 /* This is the last comparison we need to do. */
15046 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15048 arg1 = TREE_TYPE (arg1);
15049 quals1 = cp_type_quals (arg1);
15052 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15054 arg2 = TREE_TYPE (arg2);
15055 quals2 = cp_type_quals (arg2);
15058 if ((quals1 < 0) != (quals2 < 0))
15060 /* Only of the args is a reference, see if we should apply
15061 array/function pointer decay to it. This is not part of
15062 DR214, but is, IMHO, consistent with the deduction rules
15063 for the function call itself, and with our earlier
15064 implementation of the underspecified partial ordering
15065 rules. (nathan). */
15068 switch (TREE_CODE (arg1))
15071 arg1 = TREE_TYPE (arg1);
15073 case FUNCTION_TYPE:
15074 arg1 = build_pointer_type (arg1);
15083 switch (TREE_CODE (arg2))
15086 arg2 = TREE_TYPE (arg2);
15088 case FUNCTION_TYPE:
15089 arg2 = build_pointer_type (arg2);
15098 arg1 = TYPE_MAIN_VARIANT (arg1);
15099 arg2 = TYPE_MAIN_VARIANT (arg2);
15101 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15103 int i, len2 = list_length (args2);
15104 tree parmvec = make_tree_vec (1);
15105 tree argvec = make_tree_vec (len2);
15108 /* Setup the parameter vector, which contains only ARG1. */
15109 TREE_VEC_ELT (parmvec, 0) = arg1;
15111 /* Setup the argument vector, which contains the remaining
15113 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15114 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15116 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15117 argvec, UNIFY_ALLOW_NONE,
15118 /*call_args_p=*/false,
15121 /* We cannot deduce in the other direction, because ARG1 is
15122 a pack expansion but ARG2 is not. */
15125 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15127 int i, len1 = list_length (args1);
15128 tree parmvec = make_tree_vec (1);
15129 tree argvec = make_tree_vec (len1);
15132 /* Setup the parameter vector, which contains only ARG1. */
15133 TREE_VEC_ELT (parmvec, 0) = arg2;
15135 /* Setup the argument vector, which contains the remaining
15137 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15138 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15140 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15141 argvec, UNIFY_ALLOW_NONE,
15142 /*call_args_p=*/false,
15145 /* We cannot deduce in the other direction, because ARG2 is
15146 a pack expansion but ARG1 is not.*/
15152 /* The normal case, where neither argument is a pack
15154 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15155 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15158 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15159 arg2, then arg2 is not as specialized as arg1. */
15165 /* "If, for a given type, deduction succeeds in both directions
15166 (i.e., the types are identical after the transformations above)
15167 and if the type from the argument template is more cv-qualified
15168 than the type from the parameter template (as described above)
15169 that type is considered to be more specialized than the other. If
15170 neither type is more cv-qualified than the other then neither type
15171 is more specialized than the other."
15173 We check same_type_p explicitly because deduction can also succeed
15174 in both directions when there is a nondeduced context. */
15175 if (deduce1 && deduce2
15176 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0
15177 && same_type_p (arg1, arg2))
15179 if ((quals1 & quals2) == quals2)
15181 if ((quals1 & quals2) == quals1)
15185 if (lose1 && lose2)
15186 /* We've failed to deduce something in either direction.
15187 These must be unordered. */
15190 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15191 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15192 /* We have already processed all of the arguments in our
15193 handing of the pack expansion type. */
15196 args1 = TREE_CHAIN (args1);
15197 args2 = TREE_CHAIN (args2);
15200 /* "In most cases, all template parameters must have values in order for
15201 deduction to succeed, but for partial ordering purposes a template
15202 parameter may remain without a value provided it is not used in the
15203 types being used for partial ordering."
15205 Thus, if we are missing any of the targs1 we need to substitute into
15206 origs1, then pat2 is not as specialized as pat1. This can happen when
15207 there is a nondeduced context. */
15208 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15210 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15213 processing_template_decl--;
15215 /* All things being equal, if the next argument is a pack expansion
15216 for one function but not for the other, prefer the
15217 non-variadic function. FIXME this is bogus; see c++/41958. */
15219 && args1 && TREE_VALUE (args1)
15220 && args2 && TREE_VALUE (args2))
15222 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
15223 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
15226 if (lose1 == lose2)
15234 /* Determine which of two partial specializations is more specialized.
15236 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15237 to the first partial specialization. The TREE_VALUE is the
15238 innermost set of template parameters for the partial
15239 specialization. PAT2 is similar, but for the second template.
15241 Return 1 if the first partial specialization is more specialized;
15242 -1 if the second is more specialized; 0 if neither is more
15245 See [temp.class.order] for information about determining which of
15246 two templates is more specialized. */
15249 more_specialized_class (tree pat1, tree pat2)
15254 bool any_deductions = false;
15256 tmpl1 = TREE_TYPE (pat1);
15257 tmpl2 = TREE_TYPE (pat2);
15259 /* Just like what happens for functions, if we are ordering between
15260 different class template specializations, we may encounter dependent
15261 types in the arguments, and we need our dependency check functions
15262 to behave correctly. */
15263 ++processing_template_decl;
15264 targs = get_class_bindings (TREE_VALUE (pat1),
15265 CLASSTYPE_TI_ARGS (tmpl1),
15266 CLASSTYPE_TI_ARGS (tmpl2));
15270 any_deductions = true;
15273 targs = get_class_bindings (TREE_VALUE (pat2),
15274 CLASSTYPE_TI_ARGS (tmpl2),
15275 CLASSTYPE_TI_ARGS (tmpl1));
15279 any_deductions = true;
15281 --processing_template_decl;
15283 /* In the case of a tie where at least one of the class templates
15284 has a parameter pack at the end, the template with the most
15285 non-packed parameters wins. */
15288 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15289 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15291 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15292 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15293 int len1 = TREE_VEC_LENGTH (args1);
15294 int len2 = TREE_VEC_LENGTH (args2);
15296 /* We don't count the pack expansion at the end. */
15297 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15299 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15304 else if (len1 < len2)
15311 /* Return the template arguments that will produce the function signature
15312 DECL from the function template FN, with the explicit template
15313 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15314 also match. Return NULL_TREE if no satisfactory arguments could be
15318 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15320 int ntparms = DECL_NTPARMS (fn);
15321 tree targs = make_tree_vec (ntparms);
15323 tree decl_arg_types;
15325 unsigned int nargs, ix;
15328 /* Substitute the explicit template arguments into the type of DECL.
15329 The call to fn_type_unification will handle substitution into the
15331 decl_type = TREE_TYPE (decl);
15332 if (explicit_args && uses_template_parms (decl_type))
15335 tree converted_args;
15337 if (DECL_TEMPLATE_INFO (decl))
15338 tmpl = DECL_TI_TEMPLATE (decl);
15340 /* We can get here for some invalid specializations. */
15344 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15345 explicit_args, NULL_TREE,
15347 /*require_all_args=*/false,
15348 /*use_default_args=*/false);
15349 if (converted_args == error_mark_node)
15352 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15353 if (decl_type == error_mark_node)
15357 /* Never do unification on the 'this' parameter. */
15358 decl_arg_types = skip_artificial_parms_for (decl,
15359 TYPE_ARG_TYPES (decl_type));
15361 nargs = list_length (decl_arg_types);
15362 args = XALLOCAVEC (tree, nargs);
15363 for (arg = decl_arg_types, ix = 0;
15364 arg != NULL_TREE && arg != void_list_node;
15365 arg = TREE_CHAIN (arg), ++ix)
15366 args[ix] = TREE_VALUE (arg);
15368 if (fn_type_unification (fn, explicit_args, targs,
15370 (check_rettype || DECL_CONV_FN_P (fn)
15371 ? TREE_TYPE (decl_type) : NULL_TREE),
15372 DEDUCE_EXACT, LOOKUP_NORMAL))
15378 /* Return the innermost template arguments that, when applied to a
15379 template specialization whose innermost template parameters are
15380 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15383 For example, suppose we have:
15385 template <class T, class U> struct S {};
15386 template <class T> struct S<T*, int> {};
15388 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15389 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15390 int}. The resulting vector will be {double}, indicating that `T'
15391 is bound to `double'. */
15394 get_class_bindings (tree tparms, tree spec_args, tree args)
15396 int i, ntparms = TREE_VEC_LENGTH (tparms);
15398 tree innermost_deduced_args;
15400 innermost_deduced_args = make_tree_vec (ntparms);
15401 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15403 deduced_args = copy_node (args);
15404 SET_TMPL_ARGS_LEVEL (deduced_args,
15405 TMPL_ARGS_DEPTH (deduced_args),
15406 innermost_deduced_args);
15409 deduced_args = innermost_deduced_args;
15411 if (unify (tparms, deduced_args,
15412 INNERMOST_TEMPLATE_ARGS (spec_args),
15413 INNERMOST_TEMPLATE_ARGS (args),
15417 for (i = 0; i < ntparms; ++i)
15418 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15421 /* Verify that nondeduced template arguments agree with the type
15422 obtained from argument deduction.
15426 struct A { typedef int X; };
15427 template <class T, class U> struct C {};
15428 template <class T> struct C<T, typename T::X> {};
15430 Then with the instantiation `C<A, int>', we can deduce that
15431 `T' is `A' but unify () does not check whether `typename T::X'
15433 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15434 if (spec_args == error_mark_node
15435 /* We only need to check the innermost arguments; the other
15436 arguments will always agree. */
15437 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15438 INNERMOST_TEMPLATE_ARGS (args)))
15441 /* Now that we have bindings for all of the template arguments,
15442 ensure that the arguments deduced for the template template
15443 parameters have compatible template parameter lists. See the use
15444 of template_template_parm_bindings_ok_p in fn_type_unification
15445 for more information. */
15446 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15449 return deduced_args;
15452 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15453 Return the TREE_LIST node with the most specialized template, if
15454 any. If there is no most specialized template, the error_mark_node
15457 Note that this function does not look at, or modify, the
15458 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15459 returned is one of the elements of INSTANTIATIONS, callers may
15460 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15461 and retrieve it from the value returned. */
15464 most_specialized_instantiation (tree templates)
15468 ++processing_template_decl;
15471 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15475 if (get_bindings (TREE_VALUE (champ),
15476 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15477 NULL_TREE, /*check_ret=*/false))
15480 if (get_bindings (TREE_VALUE (fn),
15481 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15482 NULL_TREE, /*check_ret=*/false))
15489 /* Equally specialized, move to next function. If there
15490 is no next function, nothing's most specialized. */
15491 fn = TREE_CHAIN (fn);
15499 /* Now verify that champ is better than everything earlier in the
15500 instantiation list. */
15501 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15502 if (get_bindings (TREE_VALUE (champ),
15503 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15504 NULL_TREE, /*check_ret=*/false)
15505 || !get_bindings (TREE_VALUE (fn),
15506 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15507 NULL_TREE, /*check_ret=*/false))
15513 processing_template_decl--;
15516 return error_mark_node;
15521 /* If DECL is a specialization of some template, return the most
15522 general such template. Otherwise, returns NULL_TREE.
15524 For example, given:
15526 template <class T> struct S { template <class U> void f(U); };
15528 if TMPL is `template <class U> void S<int>::f(U)' this will return
15529 the full template. This function will not trace past partial
15530 specializations, however. For example, given in addition:
15532 template <class T> struct S<T*> { template <class U> void f(U); };
15534 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15535 `template <class T> template <class U> S<T*>::f(U)'. */
15538 most_general_template (tree decl)
15540 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15541 an immediate specialization. */
15542 if (TREE_CODE (decl) == FUNCTION_DECL)
15544 if (DECL_TEMPLATE_INFO (decl)) {
15545 decl = DECL_TI_TEMPLATE (decl);
15547 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15548 template friend. */
15549 if (TREE_CODE (decl) != TEMPLATE_DECL)
15555 /* Look for more and more general templates. */
15556 while (DECL_TEMPLATE_INFO (decl))
15558 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15559 (See cp-tree.h for details.) */
15560 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15563 if (CLASS_TYPE_P (TREE_TYPE (decl))
15564 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15567 /* Stop if we run into an explicitly specialized class template. */
15568 if (!DECL_NAMESPACE_SCOPE_P (decl)
15569 && DECL_CONTEXT (decl)
15570 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15573 decl = DECL_TI_TEMPLATE (decl);
15579 /* Return the most specialized of the class template partial
15580 specializations of TMPL which can produce TYPE, a specialization of
15581 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15582 a _TYPE node corresponding to the partial specialization, while the
15583 TREE_PURPOSE is the set of template arguments that must be
15584 substituted into the TREE_TYPE in order to generate TYPE.
15586 If the choice of partial specialization is ambiguous, a diagnostic
15587 is issued, and the error_mark_node is returned. If there are no
15588 partial specializations of TMPL matching TYPE, then NULL_TREE is
15592 most_specialized_class (tree type, tree tmpl)
15594 tree list = NULL_TREE;
15600 tree outer_args = NULL_TREE;
15602 tmpl = most_general_template (tmpl);
15603 args = CLASSTYPE_TI_ARGS (type);
15605 /* For determining which partial specialization to use, only the
15606 innermost args are interesting. */
15607 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15609 outer_args = strip_innermost_template_args (args, 1);
15610 args = INNERMOST_TEMPLATE_ARGS (args);
15613 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15615 tree partial_spec_args;
15617 tree parms = TREE_VALUE (t);
15619 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15624 ++processing_template_decl;
15626 /* Discard the outer levels of args, and then substitute in the
15627 template args from the enclosing class. */
15628 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15629 partial_spec_args = tsubst_template_args
15630 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15632 /* PARMS already refers to just the innermost parms, but the
15633 template parms in partial_spec_args had their levels lowered
15634 by tsubst, so we need to do the same for the parm list. We
15635 can't just tsubst the TREE_VEC itself, as tsubst wants to
15636 treat a TREE_VEC as an argument vector. */
15637 parms = copy_node (parms);
15638 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15639 TREE_VEC_ELT (parms, i) =
15640 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15642 --processing_template_decl;
15644 spec_args = get_class_bindings (parms,
15650 spec_args = add_to_template_args (outer_args, spec_args);
15651 list = tree_cons (spec_args, TREE_VALUE (t), list);
15652 TREE_TYPE (list) = TREE_TYPE (t);
15659 ambiguous_p = false;
15662 t = TREE_CHAIN (t);
15663 for (; t; t = TREE_CHAIN (t))
15665 fate = more_specialized_class (champ, t);
15672 t = TREE_CHAIN (t);
15675 ambiguous_p = true;
15684 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15686 fate = more_specialized_class (champ, t);
15689 ambiguous_p = true;
15696 const char *str = "candidates are:";
15697 error ("ambiguous class template instantiation for %q#T", type);
15698 for (t = list; t; t = TREE_CHAIN (t))
15700 error ("%s %+#T", str, TREE_TYPE (t));
15703 return error_mark_node;
15709 /* Explicitly instantiate DECL. */
15712 do_decl_instantiation (tree decl, tree storage)
15714 tree result = NULL_TREE;
15717 if (!decl || decl == error_mark_node)
15718 /* An error occurred, for which grokdeclarator has already issued
15719 an appropriate message. */
15721 else if (! DECL_LANG_SPECIFIC (decl))
15723 error ("explicit instantiation of non-template %q#D", decl);
15726 else if (TREE_CODE (decl) == VAR_DECL)
15728 /* There is an asymmetry here in the way VAR_DECLs and
15729 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15730 the latter, the DECL we get back will be marked as a
15731 template instantiation, and the appropriate
15732 DECL_TEMPLATE_INFO will be set up. This does not happen for
15733 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15734 should handle VAR_DECLs as it currently handles
15736 if (!DECL_CLASS_SCOPE_P (decl))
15738 error ("%qD is not a static data member of a class template", decl);
15741 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15742 if (!result || TREE_CODE (result) != VAR_DECL)
15744 error ("no matching template for %qD found", decl);
15747 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15749 error ("type %qT for explicit instantiation %qD does not match "
15750 "declared type %qT", TREE_TYPE (result), decl,
15755 else if (TREE_CODE (decl) != FUNCTION_DECL)
15757 error ("explicit instantiation of %q#D", decl);
15763 /* Check for various error cases. Note that if the explicit
15764 instantiation is valid the RESULT will currently be marked as an
15765 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15766 until we get here. */
15768 if (DECL_TEMPLATE_SPECIALIZATION (result))
15770 /* DR 259 [temp.spec].
15772 Both an explicit instantiation and a declaration of an explicit
15773 specialization shall not appear in a program unless the explicit
15774 instantiation follows a declaration of the explicit specialization.
15776 For a given set of template parameters, if an explicit
15777 instantiation of a template appears after a declaration of an
15778 explicit specialization for that template, the explicit
15779 instantiation has no effect. */
15782 else if (DECL_EXPLICIT_INSTANTIATION (result))
15786 No program shall explicitly instantiate any template more
15789 We check DECL_NOT_REALLY_EXTERN so as not to complain when
15790 the first instantiation was `extern' and the second is not,
15791 and EXTERN_P for the opposite case. */
15792 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
15793 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
15794 /* If an "extern" explicit instantiation follows an ordinary
15795 explicit instantiation, the template is instantiated. */
15799 else if (!DECL_IMPLICIT_INSTANTIATION (result))
15801 error ("no matching template for %qD found", result);
15804 else if (!DECL_TEMPLATE_INFO (result))
15806 permerror (input_location, "explicit instantiation of non-template %q#D", result);
15810 if (storage == NULL_TREE)
15812 else if (storage == ridpointers[(int) RID_EXTERN])
15814 if (!in_system_header && (cxx_dialect == cxx98))
15815 pedwarn (input_location, OPT_pedantic,
15816 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
15821 error ("storage class %qD applied to template instantiation", storage);
15823 check_explicit_instantiation_namespace (result);
15824 mark_decl_instantiated (result, extern_p);
15826 instantiate_decl (result, /*defer_ok=*/1,
15827 /*expl_inst_class_mem_p=*/false);
15831 mark_class_instantiated (tree t, int extern_p)
15833 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
15834 SET_CLASSTYPE_INTERFACE_KNOWN (t);
15835 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
15836 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
15839 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
15840 rest_of_type_compilation (t, 1);
15844 /* Called from do_type_instantiation through binding_table_foreach to
15845 do recursive instantiation for the type bound in ENTRY. */
15847 bt_instantiate_type_proc (binding_entry entry, void *data)
15849 tree storage = *(tree *) data;
15851 if (MAYBE_CLASS_TYPE_P (entry->type)
15852 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
15853 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
15856 /* Called from do_type_instantiation to instantiate a member
15857 (a member function or a static member variable) of an
15858 explicitly instantiated class template. */
15860 instantiate_class_member (tree decl, int extern_p)
15862 mark_decl_instantiated (decl, extern_p);
15864 instantiate_decl (decl, /*defer_ok=*/1,
15865 /*expl_inst_class_mem_p=*/true);
15868 /* Perform an explicit instantiation of template class T. STORAGE, if
15869 non-null, is the RID for extern, inline or static. COMPLAIN is
15870 nonzero if this is called from the parser, zero if called recursively,
15871 since the standard is unclear (as detailed below). */
15874 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
15879 int previous_instantiation_extern_p = 0;
15881 if (TREE_CODE (t) == TYPE_DECL)
15884 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
15886 error ("explicit instantiation of non-template type %qT", t);
15892 if (!COMPLETE_TYPE_P (t))
15894 if (complain & tf_error)
15895 error ("explicit instantiation of %q#T before definition of template",
15900 if (storage != NULL_TREE)
15902 if (!in_system_header)
15904 if (storage == ridpointers[(int) RID_EXTERN])
15906 if (cxx_dialect == cxx98)
15907 pedwarn (input_location, OPT_pedantic,
15908 "ISO C++ 1998 forbids the use of %<extern%> on "
15909 "explicit instantiations");
15912 pedwarn (input_location, OPT_pedantic,
15913 "ISO C++ forbids the use of %qE"
15914 " on explicit instantiations", storage);
15917 if (storage == ridpointers[(int) RID_INLINE])
15919 else if (storage == ridpointers[(int) RID_EXTERN])
15921 else if (storage == ridpointers[(int) RID_STATIC])
15925 error ("storage class %qD applied to template instantiation",
15931 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
15933 /* DR 259 [temp.spec].
15935 Both an explicit instantiation and a declaration of an explicit
15936 specialization shall not appear in a program unless the explicit
15937 instantiation follows a declaration of the explicit specialization.
15939 For a given set of template parameters, if an explicit
15940 instantiation of a template appears after a declaration of an
15941 explicit specialization for that template, the explicit
15942 instantiation has no effect. */
15945 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
15949 No program shall explicitly instantiate any template more
15952 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
15953 instantiation was `extern'. If EXTERN_P then the second is.
15954 These cases are OK. */
15955 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
15957 if (!previous_instantiation_extern_p && !extern_p
15958 && (complain & tf_error))
15959 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
15961 /* If we've already instantiated the template, just return now. */
15962 if (!CLASSTYPE_INTERFACE_ONLY (t))
15966 check_explicit_instantiation_namespace (TYPE_NAME (t));
15967 mark_class_instantiated (t, extern_p);
15975 /* In contrast to implicit instantiation, where only the
15976 declarations, and not the definitions, of members are
15977 instantiated, we have here:
15981 The explicit instantiation of a class template specialization
15982 implies the instantiation of all of its members not
15983 previously explicitly specialized in the translation unit
15984 containing the explicit instantiation.
15986 Of course, we can't instantiate member template classes, since
15987 we don't have any arguments for them. Note that the standard
15988 is unclear on whether the instantiation of the members are
15989 *explicit* instantiations or not. However, the most natural
15990 interpretation is that it should be an explicit instantiation. */
15993 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
15994 if (TREE_CODE (tmp) == FUNCTION_DECL
15995 && DECL_TEMPLATE_INSTANTIATION (tmp))
15996 instantiate_class_member (tmp, extern_p);
15998 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
15999 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
16000 instantiate_class_member (tmp, extern_p);
16002 if (CLASSTYPE_NESTED_UTDS (t))
16003 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
16004 bt_instantiate_type_proc, &storage);
16008 /* Given a function DECL, which is a specialization of TMPL, modify
16009 DECL to be a re-instantiation of TMPL with the same template
16010 arguments. TMPL should be the template into which tsubst'ing
16011 should occur for DECL, not the most general template.
16013 One reason for doing this is a scenario like this:
16016 void f(const T&, int i);
16018 void g() { f(3, 7); }
16021 void f(const T& t, const int i) { }
16023 Note that when the template is first instantiated, with
16024 instantiate_template, the resulting DECL will have no name for the
16025 first parameter, and the wrong type for the second. So, when we go
16026 to instantiate the DECL, we regenerate it. */
16029 regenerate_decl_from_template (tree decl, tree tmpl)
16031 /* The arguments used to instantiate DECL, from the most general
16036 args = DECL_TI_ARGS (decl);
16037 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
16039 /* Make sure that we can see identifiers, and compute access
16041 push_access_scope (decl);
16043 if (TREE_CODE (decl) == FUNCTION_DECL)
16051 args_depth = TMPL_ARGS_DEPTH (args);
16052 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16053 if (args_depth > parms_depth)
16054 args = get_innermost_template_args (args, parms_depth);
16056 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16057 args, tf_error, NULL_TREE);
16059 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16062 /* Merge parameter declarations. */
16063 decl_parm = skip_artificial_parms_for (decl,
16064 DECL_ARGUMENTS (decl));
16066 = skip_artificial_parms_for (code_pattern,
16067 DECL_ARGUMENTS (code_pattern));
16068 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16073 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16074 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16075 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16077 parm_type = type_decays_to (parm_type);
16078 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16079 TREE_TYPE (decl_parm) = parm_type;
16080 attributes = DECL_ATTRIBUTES (pattern_parm);
16081 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16083 DECL_ATTRIBUTES (decl_parm) = attributes;
16084 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16086 decl_parm = TREE_CHAIN (decl_parm);
16087 pattern_parm = TREE_CHAIN (pattern_parm);
16089 /* Merge any parameters that match with the function parameter
16091 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16094 tree expanded_types;
16095 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16096 the parameters in this function parameter pack. */
16097 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16098 args, tf_error, NULL_TREE);
16099 len = TREE_VEC_LENGTH (expanded_types);
16100 for (i = 0; i < len; i++)
16105 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16106 /* Rename the parameter to include the index. */
16107 DECL_NAME (decl_parm) =
16108 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16109 parm_type = TREE_VEC_ELT (expanded_types, i);
16110 parm_type = type_decays_to (parm_type);
16111 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16112 TREE_TYPE (decl_parm) = parm_type;
16113 attributes = DECL_ATTRIBUTES (pattern_parm);
16114 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16116 DECL_ATTRIBUTES (decl_parm) = attributes;
16117 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16119 decl_parm = TREE_CHAIN (decl_parm);
16122 /* Merge additional specifiers from the CODE_PATTERN. */
16123 if (DECL_DECLARED_INLINE_P (code_pattern)
16124 && !DECL_DECLARED_INLINE_P (decl))
16125 DECL_DECLARED_INLINE_P (decl) = 1;
16127 else if (TREE_CODE (decl) == VAR_DECL)
16128 DECL_INITIAL (decl) =
16129 tsubst_expr (DECL_INITIAL (code_pattern), args,
16130 tf_error, DECL_TI_TEMPLATE (decl),
16131 /*integral_constant_expression_p=*/false);
16133 gcc_unreachable ();
16135 pop_access_scope (decl);
16138 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16139 substituted to get DECL. */
16142 template_for_substitution (tree decl)
16144 tree tmpl = DECL_TI_TEMPLATE (decl);
16146 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16147 for the instantiation. This is not always the most general
16148 template. Consider, for example:
16151 struct S { template <class U> void f();
16152 template <> void f<int>(); };
16154 and an instantiation of S<double>::f<int>. We want TD to be the
16155 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16156 while (/* An instantiation cannot have a definition, so we need a
16157 more general template. */
16158 DECL_TEMPLATE_INSTANTIATION (tmpl)
16159 /* We must also deal with friend templates. Given:
16161 template <class T> struct S {
16162 template <class U> friend void f() {};
16165 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16166 so far as the language is concerned, but that's still
16167 where we get the pattern for the instantiation from. On
16168 other hand, if the definition comes outside the class, say:
16170 template <class T> struct S {
16171 template <class U> friend void f();
16173 template <class U> friend void f() {}
16175 we don't need to look any further. That's what the check for
16176 DECL_INITIAL is for. */
16177 || (TREE_CODE (decl) == FUNCTION_DECL
16178 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16179 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16181 /* The present template, TD, should not be a definition. If it
16182 were a definition, we should be using it! Note that we
16183 cannot restructure the loop to just keep going until we find
16184 a template with a definition, since that might go too far if
16185 a specialization was declared, but not defined. */
16186 gcc_assert (TREE_CODE (decl) != VAR_DECL
16187 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16189 /* Fetch the more general template. */
16190 tmpl = DECL_TI_TEMPLATE (tmpl);
16196 /* Returns true if we need to instantiate this template instance even if we
16197 know we aren't going to emit it.. */
16200 always_instantiate_p (tree decl)
16202 /* We always instantiate inline functions so that we can inline them. An
16203 explicit instantiation declaration prohibits implicit instantiation of
16204 non-inline functions. With high levels of optimization, we would
16205 normally inline non-inline functions -- but we're not allowed to do
16206 that for "extern template" functions. Therefore, we check
16207 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16208 return ((TREE_CODE (decl) == FUNCTION_DECL
16209 && DECL_DECLARED_INLINE_P (decl))
16210 /* And we need to instantiate static data members so that
16211 their initializers are available in integral constant
16213 || (TREE_CODE (decl) == VAR_DECL
16214 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16217 /* Produce the definition of D, a _DECL generated from a template. If
16218 DEFER_OK is nonzero, then we don't have to actually do the
16219 instantiation now; we just have to do it sometime. Normally it is
16220 an error if this is an explicit instantiation but D is undefined.
16221 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16222 explicitly instantiated class template. */
16225 instantiate_decl (tree d, int defer_ok,
16226 bool expl_inst_class_mem_p)
16228 tree tmpl = DECL_TI_TEMPLATE (d);
16235 bool pattern_defined;
16237 location_t saved_loc = input_location;
16240 /* This function should only be used to instantiate templates for
16241 functions and static member variables. */
16242 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16243 || TREE_CODE (d) == VAR_DECL);
16245 /* Variables are never deferred; if instantiation is required, they
16246 are instantiated right away. That allows for better code in the
16247 case that an expression refers to the value of the variable --
16248 if the variable has a constant value the referring expression can
16249 take advantage of that fact. */
16250 if (TREE_CODE (d) == VAR_DECL)
16253 /* Don't instantiate cloned functions. Instead, instantiate the
16254 functions they cloned. */
16255 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16256 d = DECL_CLONED_FUNCTION (d);
16258 if (DECL_TEMPLATE_INSTANTIATED (d)
16259 || DECL_TEMPLATE_SPECIALIZATION (d))
16260 /* D has already been instantiated or explicitly specialized, so
16261 there's nothing for us to do here.
16263 It might seem reasonable to check whether or not D is an explicit
16264 instantiation, and, if so, stop here. But when an explicit
16265 instantiation is deferred until the end of the compilation,
16266 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16267 the instantiation. */
16270 /* Check to see whether we know that this template will be
16271 instantiated in some other file, as with "extern template"
16273 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16275 /* In general, we do not instantiate such templates. */
16276 if (external_p && !always_instantiate_p (d))
16279 gen_tmpl = most_general_template (tmpl);
16280 gen_args = DECL_TI_ARGS (d);
16282 if (tmpl != gen_tmpl)
16283 /* We should already have the extra args. */
16284 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16285 == TMPL_ARGS_DEPTH (gen_args));
16286 /* And what's in the hash table should match D. */
16287 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16288 || spec == NULL_TREE);
16290 /* This needs to happen before any tsubsting. */
16291 if (! push_tinst_level (d))
16294 timevar_push (TV_PARSE);
16296 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16297 for the instantiation. */
16298 td = template_for_substitution (d);
16299 code_pattern = DECL_TEMPLATE_RESULT (td);
16301 /* We should never be trying to instantiate a member of a class
16302 template or partial specialization. */
16303 gcc_assert (d != code_pattern);
16305 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16306 || DECL_TEMPLATE_SPECIALIZATION (td))
16307 /* In the case of a friend template whose definition is provided
16308 outside the class, we may have too many arguments. Drop the
16309 ones we don't need. The same is true for specializations. */
16310 args = get_innermost_template_args
16311 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16315 if (TREE_CODE (d) == FUNCTION_DECL)
16316 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16318 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16320 /* We may be in the middle of deferred access check. Disable it now. */
16321 push_deferring_access_checks (dk_no_deferred);
16323 /* Unless an explicit instantiation directive has already determined
16324 the linkage of D, remember that a definition is available for
16326 if (pattern_defined
16327 && !DECL_INTERFACE_KNOWN (d)
16328 && !DECL_NOT_REALLY_EXTERN (d))
16329 mark_definable (d);
16331 input_location = DECL_SOURCE_LOCATION (d);
16333 /* If D is a member of an explicitly instantiated class template,
16334 and no definition is available, treat it like an implicit
16336 if (!pattern_defined && expl_inst_class_mem_p
16337 && DECL_EXPLICIT_INSTANTIATION (d))
16339 DECL_NOT_REALLY_EXTERN (d) = 0;
16340 DECL_INTERFACE_KNOWN (d) = 0;
16341 SET_DECL_IMPLICIT_INSTANTIATION (d);
16344 /* Recheck the substitutions to obtain any warning messages
16345 about ignoring cv qualifiers. Don't do this for artificial decls,
16346 as it breaks the context-sensitive substitution for lambda op(). */
16347 if (!defer_ok && !DECL_ARTIFICIAL (d))
16349 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16350 tree type = TREE_TYPE (gen);
16352 /* Make sure that we can see identifiers, and compute access
16353 correctly. D is already the target FUNCTION_DECL with the
16355 push_access_scope (d);
16357 if (TREE_CODE (gen) == FUNCTION_DECL)
16359 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16360 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16362 /* Don't simply tsubst the function type, as that will give
16363 duplicate warnings about poor parameter qualifications.
16364 The function arguments are the same as the decl_arguments
16365 without the top level cv qualifiers. */
16366 type = TREE_TYPE (type);
16368 tsubst (type, gen_args, tf_warning_or_error, d);
16370 pop_access_scope (d);
16373 /* Defer all other templates, unless we have been explicitly
16374 forbidden from doing so. */
16375 if (/* If there is no definition, we cannot instantiate the
16378 /* If it's OK to postpone instantiation, do so. */
16380 /* If this is a static data member that will be defined
16381 elsewhere, we don't want to instantiate the entire data
16382 member, but we do want to instantiate the initializer so that
16383 we can substitute that elsewhere. */
16384 || (external_p && TREE_CODE (d) == VAR_DECL))
16386 /* The definition of the static data member is now required so
16387 we must substitute the initializer. */
16388 if (TREE_CODE (d) == VAR_DECL
16389 && !DECL_INITIAL (d)
16390 && DECL_INITIAL (code_pattern))
16395 ns = decl_namespace_context (d);
16396 push_nested_namespace (ns);
16397 push_nested_class (DECL_CONTEXT (d));
16398 init = tsubst_expr (DECL_INITIAL (code_pattern),
16400 tf_warning_or_error, NULL_TREE,
16401 /*integral_constant_expression_p=*/false);
16402 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16403 /*asmspec_tree=*/NULL_TREE,
16404 LOOKUP_ONLYCONVERTING);
16405 pop_nested_class ();
16406 pop_nested_namespace (ns);
16409 /* We restore the source position here because it's used by
16410 add_pending_template. */
16411 input_location = saved_loc;
16413 if (at_eof && !pattern_defined
16414 && DECL_EXPLICIT_INSTANTIATION (d)
16415 && DECL_NOT_REALLY_EXTERN (d))
16418 The definition of a non-exported function template, a
16419 non-exported member function template, or a non-exported
16420 member function or static data member of a class template
16421 shall be present in every translation unit in which it is
16422 explicitly instantiated. */
16423 permerror (input_location, "explicit instantiation of %qD "
16424 "but no definition available", d);
16426 /* ??? Historically, we have instantiated inline functions, even
16427 when marked as "extern template". */
16428 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16429 add_pending_template (d);
16432 /* Tell the repository that D is available in this translation unit
16433 -- and see if it is supposed to be instantiated here. */
16434 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16436 /* In a PCH file, despite the fact that the repository hasn't
16437 requested instantiation in the PCH it is still possible that
16438 an instantiation will be required in a file that includes the
16441 add_pending_template (d);
16442 /* Instantiate inline functions so that the inliner can do its
16443 job, even though we'll not be emitting a copy of this
16445 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16449 need_push = !cfun || !global_bindings_p ();
16451 push_to_top_level ();
16453 /* Mark D as instantiated so that recursive calls to
16454 instantiate_decl do not try to instantiate it again. */
16455 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16457 /* Regenerate the declaration in case the template has been modified
16458 by a subsequent redeclaration. */
16459 regenerate_decl_from_template (d, td);
16461 /* We already set the file and line above. Reset them now in case
16462 they changed as a result of calling regenerate_decl_from_template. */
16463 input_location = DECL_SOURCE_LOCATION (d);
16465 if (TREE_CODE (d) == VAR_DECL)
16469 /* Clear out DECL_RTL; whatever was there before may not be right
16470 since we've reset the type of the declaration. */
16471 SET_DECL_RTL (d, NULL_RTX);
16472 DECL_IN_AGGR_P (d) = 0;
16474 /* The initializer is placed in DECL_INITIAL by
16475 regenerate_decl_from_template. Pull it out so that
16476 cp_finish_decl can process it. */
16477 init = DECL_INITIAL (d);
16478 DECL_INITIAL (d) = NULL_TREE;
16479 DECL_INITIALIZED_P (d) = 0;
16481 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16482 initializer. That function will defer actual emission until
16483 we have a chance to determine linkage. */
16484 DECL_EXTERNAL (d) = 0;
16486 /* Enter the scope of D so that access-checking works correctly. */
16487 push_nested_class (DECL_CONTEXT (d));
16488 cp_finish_decl (d, init, false, NULL_TREE, 0);
16489 pop_nested_class ();
16491 else if (TREE_CODE (d) == FUNCTION_DECL)
16493 htab_t saved_local_specializations;
16498 /* Save away the current list, in case we are instantiating one
16499 template from within the body of another. */
16500 saved_local_specializations = local_specializations;
16502 /* Set up the list of local specializations. */
16503 local_specializations = htab_create (37,
16504 hash_local_specialization,
16505 eq_local_specializations,
16508 /* Set up context. */
16509 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16511 /* Create substitution entries for the parameters. */
16512 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16513 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16514 spec_parm = DECL_ARGUMENTS (d);
16515 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16517 register_local_specialization (spec_parm, tmpl_parm);
16518 spec_parm = skip_artificial_parms_for (d, spec_parm);
16519 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16521 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16523 register_local_specialization (spec_parm, tmpl_parm);
16524 tmpl_parm = TREE_CHAIN (tmpl_parm);
16525 spec_parm = TREE_CHAIN (spec_parm);
16527 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16529 /* Register the (value) argument pack as a specialization of
16530 TMPL_PARM, then move on. */
16531 tree argpack = make_fnparm_pack (spec_parm);
16532 register_local_specialization (argpack, tmpl_parm);
16533 tmpl_parm = TREE_CHAIN (tmpl_parm);
16534 spec_parm = NULL_TREE;
16536 gcc_assert (!spec_parm);
16538 /* Substitute into the body of the function. */
16539 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16540 tf_warning_or_error, tmpl,
16541 /*integral_constant_expression_p=*/false);
16543 /* Set the current input_location to the end of the function
16544 so that finish_function knows where we are. */
16545 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
16547 /* We don't need the local specializations any more. */
16548 htab_delete (local_specializations);
16549 local_specializations = saved_local_specializations;
16551 /* Finish the function. */
16552 d = finish_function (0);
16553 expand_or_defer_fn (d);
16556 /* We're not deferring instantiation any more. */
16557 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16560 pop_from_top_level ();
16563 input_location = saved_loc;
16564 pop_deferring_access_checks ();
16565 pop_tinst_level ();
16567 timevar_pop (TV_PARSE);
16572 /* Run through the list of templates that we wish we could
16573 instantiate, and instantiate any we can. RETRIES is the
16574 number of times we retry pending template instantiation. */
16577 instantiate_pending_templates (int retries)
16580 location_t saved_loc = input_location;
16582 /* Instantiating templates may trigger vtable generation. This in turn
16583 may require further template instantiations. We place a limit here
16584 to avoid infinite loop. */
16585 if (pending_templates && retries >= max_tinst_depth)
16587 tree decl = pending_templates->tinst->decl;
16589 error ("template instantiation depth exceeds maximum of %d"
16590 " instantiating %q+D, possibly from virtual table generation"
16591 " (use -ftemplate-depth-NN to increase the maximum)",
16592 max_tinst_depth, decl);
16593 if (TREE_CODE (decl) == FUNCTION_DECL)
16594 /* Pretend that we defined it. */
16595 DECL_INITIAL (decl) = error_mark_node;
16601 struct pending_template **t = &pending_templates;
16602 struct pending_template *last = NULL;
16606 tree instantiation = reopen_tinst_level ((*t)->tinst);
16607 bool complete = false;
16609 if (TYPE_P (instantiation))
16613 if (!COMPLETE_TYPE_P (instantiation))
16615 instantiate_class_template (instantiation);
16616 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16617 for (fn = TYPE_METHODS (instantiation);
16619 fn = TREE_CHAIN (fn))
16620 if (! DECL_ARTIFICIAL (fn))
16621 instantiate_decl (fn,
16623 /*expl_inst_class_mem_p=*/false);
16624 if (COMPLETE_TYPE_P (instantiation))
16628 complete = COMPLETE_TYPE_P (instantiation);
16632 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16633 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16636 = instantiate_decl (instantiation,
16638 /*expl_inst_class_mem_p=*/false);
16639 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16643 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16644 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16648 /* If INSTANTIATION has been instantiated, then we don't
16649 need to consider it again in the future. */
16657 current_tinst_level = NULL;
16659 last_pending_template = last;
16661 while (reconsider);
16663 input_location = saved_loc;
16666 /* Substitute ARGVEC into T, which is a list of initializers for
16667 either base class or a non-static data member. The TREE_PURPOSEs
16668 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16669 instantiate_decl. */
16672 tsubst_initializer_list (tree t, tree argvec)
16674 tree inits = NULL_TREE;
16676 for (; t; t = TREE_CHAIN (t))
16680 tree expanded_bases = NULL_TREE;
16681 tree expanded_arguments = NULL_TREE;
16684 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16689 /* Expand the base class expansion type into separate base
16691 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16692 tf_warning_or_error,
16694 if (expanded_bases == error_mark_node)
16697 /* We'll be building separate TREE_LISTs of arguments for
16699 len = TREE_VEC_LENGTH (expanded_bases);
16700 expanded_arguments = make_tree_vec (len);
16701 for (i = 0; i < len; i++)
16702 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16704 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16705 expand each argument in the TREE_VALUE of t. */
16706 expr = make_node (EXPR_PACK_EXPANSION);
16707 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16708 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16710 if (TREE_VALUE (t) == void_type_node)
16711 /* VOID_TYPE_NODE is used to indicate
16712 value-initialization. */
16714 for (i = 0; i < len; i++)
16715 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16719 /* Substitute parameter packs into each argument in the
16721 in_base_initializer = 1;
16722 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16724 tree expanded_exprs;
16726 /* Expand the argument. */
16727 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16729 = tsubst_pack_expansion (expr, argvec,
16730 tf_warning_or_error,
16732 if (expanded_exprs == error_mark_node)
16735 /* Prepend each of the expanded expressions to the
16736 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16737 for (i = 0; i < len; i++)
16739 TREE_VEC_ELT (expanded_arguments, i) =
16740 tree_cons (NULL_TREE,
16741 TREE_VEC_ELT (expanded_exprs, i),
16742 TREE_VEC_ELT (expanded_arguments, i));
16745 in_base_initializer = 0;
16747 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16748 since we built them backwards. */
16749 for (i = 0; i < len; i++)
16751 TREE_VEC_ELT (expanded_arguments, i) =
16752 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16757 for (i = 0; i < len; ++i)
16759 if (expanded_bases)
16761 decl = TREE_VEC_ELT (expanded_bases, i);
16762 decl = expand_member_init (decl);
16763 init = TREE_VEC_ELT (expanded_arguments, i);
16767 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16768 tf_warning_or_error, NULL_TREE);
16770 decl = expand_member_init (decl);
16771 if (decl && !DECL_P (decl))
16772 in_base_initializer = 1;
16774 init = tsubst_expr (TREE_VALUE (t), argvec,
16775 tf_warning_or_error, NULL_TREE,
16776 /*integral_constant_expression_p=*/false);
16777 in_base_initializer = 0;
16782 init = build_tree_list (decl, init);
16783 TREE_CHAIN (init) = inits;
16791 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
16794 set_current_access_from_decl (tree decl)
16796 if (TREE_PRIVATE (decl))
16797 current_access_specifier = access_private_node;
16798 else if (TREE_PROTECTED (decl))
16799 current_access_specifier = access_protected_node;
16801 current_access_specifier = access_public_node;
16804 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
16805 is the instantiation (which should have been created with
16806 start_enum) and ARGS are the template arguments to use. */
16809 tsubst_enum (tree tag, tree newtag, tree args)
16813 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
16818 decl = TREE_VALUE (e);
16819 /* Note that in a template enum, the TREE_VALUE is the
16820 CONST_DECL, not the corresponding INTEGER_CST. */
16821 value = tsubst_expr (DECL_INITIAL (decl),
16822 args, tf_warning_or_error, NULL_TREE,
16823 /*integral_constant_expression_p=*/true);
16825 /* Give this enumeration constant the correct access. */
16826 set_current_access_from_decl (decl);
16828 /* Actually build the enumerator itself. */
16829 build_enumerator (DECL_NAME (decl), value, newtag);
16832 finish_enum (newtag);
16833 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
16834 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
16837 /* DECL is a FUNCTION_DECL that is a template specialization. Return
16838 its type -- but without substituting the innermost set of template
16839 arguments. So, innermost set of template parameters will appear in
16843 get_mostly_instantiated_function_type (tree decl)
16851 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
16852 targs = DECL_TI_ARGS (decl);
16853 tparms = DECL_TEMPLATE_PARMS (tmpl);
16854 parm_depth = TMPL_PARMS_DEPTH (tparms);
16856 /* There should be as many levels of arguments as there are levels
16858 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
16860 fn_type = TREE_TYPE (tmpl);
16862 if (parm_depth == 1)
16863 /* No substitution is necessary. */
16867 int i, save_access_control;
16870 /* Replace the innermost level of the TARGS with NULL_TREEs to
16871 let tsubst know not to substitute for those parameters. */
16872 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
16873 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
16874 SET_TMPL_ARGS_LEVEL (partial_args, i,
16875 TMPL_ARGS_LEVEL (targs, i));
16876 SET_TMPL_ARGS_LEVEL (partial_args,
16877 TMPL_ARGS_DEPTH (targs),
16878 make_tree_vec (DECL_NTPARMS (tmpl)));
16880 /* Disable access control as this function is used only during
16882 save_access_control = flag_access_control;
16883 flag_access_control = 0;
16885 ++processing_template_decl;
16886 /* Now, do the (partial) substitution to figure out the
16887 appropriate function type. */
16888 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
16889 --processing_template_decl;
16891 /* Substitute into the template parameters to obtain the real
16892 innermost set of parameters. This step is important if the
16893 innermost set of template parameters contains value
16894 parameters whose types depend on outer template parameters. */
16895 TREE_VEC_LENGTH (partial_args)--;
16896 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
16898 flag_access_control = save_access_control;
16904 /* Return truthvalue if we're processing a template different from
16905 the last one involved in diagnostics. */
16907 problematic_instantiation_changed (void)
16909 return last_template_error_tick != tinst_level_tick;
16912 /* Remember current template involved in diagnostics. */
16914 record_last_problematic_instantiation (void)
16916 last_template_error_tick = tinst_level_tick;
16919 struct tinst_level *
16920 current_instantiation (void)
16922 return current_tinst_level;
16925 /* [temp.param] Check that template non-type parm TYPE is of an allowable
16926 type. Return zero for ok, nonzero for disallowed. Issue error and
16927 warning messages under control of COMPLAIN. */
16930 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
16932 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
16934 else if (POINTER_TYPE_P (type))
16936 else if (TYPE_PTR_TO_MEMBER_P (type))
16938 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
16940 else if (TREE_CODE (type) == TYPENAME_TYPE)
16943 if (complain & tf_error)
16944 error ("%q#T is not a valid type for a template constant parameter", type);
16948 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
16949 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
16952 dependent_type_p_r (tree type)
16958 A type is dependent if it is:
16960 -- a template parameter. Template template parameters are types
16961 for us (since TYPE_P holds true for them) so we handle
16963 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16964 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
16966 /* -- a qualified-id with a nested-name-specifier which contains a
16967 class-name that names a dependent type or whose unqualified-id
16968 names a dependent type. */
16969 if (TREE_CODE (type) == TYPENAME_TYPE)
16971 /* -- a cv-qualified type where the cv-unqualified type is
16973 type = TYPE_MAIN_VARIANT (type);
16974 /* -- a compound type constructed from any dependent type. */
16975 if (TYPE_PTR_TO_MEMBER_P (type))
16976 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
16977 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
16979 else if (TREE_CODE (type) == POINTER_TYPE
16980 || TREE_CODE (type) == REFERENCE_TYPE)
16981 return dependent_type_p (TREE_TYPE (type));
16982 else if (TREE_CODE (type) == FUNCTION_TYPE
16983 || TREE_CODE (type) == METHOD_TYPE)
16987 if (dependent_type_p (TREE_TYPE (type)))
16989 for (arg_type = TYPE_ARG_TYPES (type);
16991 arg_type = TREE_CHAIN (arg_type))
16992 if (dependent_type_p (TREE_VALUE (arg_type)))
16996 /* -- an array type constructed from any dependent type or whose
16997 size is specified by a constant expression that is
16998 value-dependent. */
16999 if (TREE_CODE (type) == ARRAY_TYPE)
17001 if (TYPE_DOMAIN (type)
17002 && dependent_type_p (TYPE_DOMAIN (type)))
17004 return dependent_type_p (TREE_TYPE (type));
17006 else if (TREE_CODE (type) == INTEGER_TYPE
17007 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
17009 /* If this is the TYPE_DOMAIN of an array type, consider it
17010 dependent. We already checked for value-dependence in
17011 compute_array_index_type. */
17012 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
17015 /* -- a template-id in which either the template name is a template
17017 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
17019 /* ... or any of the template arguments is a dependent type or
17020 an expression that is type-dependent or value-dependent. */
17021 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
17022 && (any_dependent_template_arguments_p
17023 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
17026 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
17027 argument of the `typeof' expression is not type-dependent, then
17028 it should already been have resolved. */
17029 if (TREE_CODE (type) == TYPEOF_TYPE
17030 || TREE_CODE (type) == DECLTYPE_TYPE)
17033 /* A template argument pack is dependent if any of its packed
17035 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
17037 tree args = ARGUMENT_PACK_ARGS (type);
17038 int i, len = TREE_VEC_LENGTH (args);
17039 for (i = 0; i < len; ++i)
17040 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17044 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17045 be template parameters. */
17046 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17049 /* The standard does not specifically mention types that are local
17050 to template functions or local classes, but they should be
17051 considered dependent too. For example:
17053 template <int I> void f() {
17058 The size of `E' cannot be known until the value of `I' has been
17059 determined. Therefore, `E' must be considered dependent. */
17060 scope = TYPE_CONTEXT (type);
17061 if (scope && TYPE_P (scope))
17062 return dependent_type_p (scope);
17063 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17064 return type_dependent_expression_p (scope);
17066 /* Other types are non-dependent. */
17070 /* Returns TRUE if TYPE is dependent, in the sense of
17071 [temp.dep.type]. */
17074 dependent_type_p (tree type)
17076 /* If there are no template parameters in scope, then there can't be
17077 any dependent types. */
17078 if (!processing_template_decl)
17080 /* If we are not processing a template, then nobody should be
17081 providing us with a dependent type. */
17083 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17087 /* If the type is NULL, we have not computed a type for the entity
17088 in question; in that case, the type is dependent. */
17092 /* Erroneous types can be considered non-dependent. */
17093 if (type == error_mark_node)
17096 /* If we have not already computed the appropriate value for TYPE,
17098 if (!TYPE_DEPENDENT_P_VALID (type))
17100 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17101 TYPE_DEPENDENT_P_VALID (type) = 1;
17104 return TYPE_DEPENDENT_P (type);
17107 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17108 lookup. In other words, a dependent type that is not the current
17112 dependent_scope_p (tree scope)
17114 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17115 && !currently_open_class (scope));
17118 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
17121 dependent_scope_ref_p (tree expression, bool criterion (tree))
17126 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
17128 if (!TYPE_P (TREE_OPERAND (expression, 0)))
17131 scope = TREE_OPERAND (expression, 0);
17132 name = TREE_OPERAND (expression, 1);
17136 An id-expression is type-dependent if it contains a
17137 nested-name-specifier that contains a class-name that names a
17139 /* The suggested resolution to Core Issue 224 implies that if the
17140 qualifying type is the current class, then we must peek
17143 && currently_open_class (scope)
17144 && !criterion (name))
17146 if (dependent_type_p (scope))
17152 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17153 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17157 value_dependent_expression_p (tree expression)
17159 if (!processing_template_decl)
17162 /* A name declared with a dependent type. */
17163 if (DECL_P (expression) && type_dependent_expression_p (expression))
17166 switch (TREE_CODE (expression))
17168 case IDENTIFIER_NODE:
17169 /* A name that has not been looked up -- must be dependent. */
17172 case TEMPLATE_PARM_INDEX:
17173 /* A non-type template parm. */
17177 /* A non-type template parm. */
17178 if (DECL_TEMPLATE_PARM_P (expression))
17180 return value_dependent_expression_p (DECL_INITIAL (expression));
17183 /* A constant with integral or enumeration type and is initialized
17184 with an expression that is value-dependent. */
17185 if (DECL_INITIAL (expression)
17186 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17187 && value_dependent_expression_p (DECL_INITIAL (expression)))
17191 case DYNAMIC_CAST_EXPR:
17192 case STATIC_CAST_EXPR:
17193 case CONST_CAST_EXPR:
17194 case REINTERPRET_CAST_EXPR:
17196 /* These expressions are value-dependent if the type to which
17197 the cast occurs is dependent or the expression being casted
17198 is value-dependent. */
17200 tree type = TREE_TYPE (expression);
17202 if (dependent_type_p (type))
17205 /* A functional cast has a list of operands. */
17206 expression = TREE_OPERAND (expression, 0);
17209 /* If there are no operands, it must be an expression such
17210 as "int()". This should not happen for aggregate types
17211 because it would form non-constant expressions. */
17212 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17217 if (TREE_CODE (expression) == TREE_LIST)
17218 return any_value_dependent_elements_p (expression);
17220 return value_dependent_expression_p (expression);
17225 /* A `sizeof' expression is value-dependent if the operand is
17226 type-dependent or is a pack expansion. */
17227 expression = TREE_OPERAND (expression, 0);
17228 if (PACK_EXPANSION_P (expression))
17230 else if (TYPE_P (expression))
17231 return dependent_type_p (expression);
17232 return type_dependent_expression_p (expression);
17235 return dependent_scope_ref_p (expression, value_dependent_expression_p);
17237 case COMPONENT_REF:
17238 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17239 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17242 /* A CALL_EXPR may appear in a constant expression if it is a
17243 call to a builtin function, e.g., __builtin_constant_p. All
17244 such calls are value-dependent. */
17247 case NONTYPE_ARGUMENT_PACK:
17248 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17249 is value-dependent. */
17251 tree values = ARGUMENT_PACK_ARGS (expression);
17252 int i, len = TREE_VEC_LENGTH (values);
17254 for (i = 0; i < len; ++i)
17255 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17263 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17264 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17265 || (type2 ? dependent_type_p (type2) : false));
17269 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17270 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17273 /* A constant expression is value-dependent if any subexpression is
17274 value-dependent. */
17275 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17277 case tcc_reference:
17279 return (value_dependent_expression_p
17280 (TREE_OPERAND (expression, 0)));
17282 case tcc_comparison:
17284 return ((value_dependent_expression_p
17285 (TREE_OPERAND (expression, 0)))
17286 || (value_dependent_expression_p
17287 (TREE_OPERAND (expression, 1))));
17289 case tcc_expression:
17293 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17294 /* In some cases, some of the operands may be missing.
17295 (For example, in the case of PREDECREMENT_EXPR, the
17296 amount to increment by may be missing.) That doesn't
17297 make the expression dependent. */
17298 if (TREE_OPERAND (expression, i)
17299 && (value_dependent_expression_p
17300 (TREE_OPERAND (expression, i))))
17310 /* The expression is not value-dependent. */
17314 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17315 [temp.dep.expr]. */
17318 type_dependent_expression_p (tree expression)
17320 if (!processing_template_decl)
17323 if (expression == error_mark_node)
17326 /* An unresolved name is always dependent. */
17327 if (TREE_CODE (expression) == IDENTIFIER_NODE
17328 || TREE_CODE (expression) == USING_DECL)
17331 /* Some expression forms are never type-dependent. */
17332 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17333 || TREE_CODE (expression) == SIZEOF_EXPR
17334 || TREE_CODE (expression) == ALIGNOF_EXPR
17335 || TREE_CODE (expression) == TRAIT_EXPR
17336 || TREE_CODE (expression) == TYPEID_EXPR
17337 || TREE_CODE (expression) == DELETE_EXPR
17338 || TREE_CODE (expression) == VEC_DELETE_EXPR
17339 || TREE_CODE (expression) == THROW_EXPR)
17342 /* The types of these expressions depends only on the type to which
17343 the cast occurs. */
17344 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17345 || TREE_CODE (expression) == STATIC_CAST_EXPR
17346 || TREE_CODE (expression) == CONST_CAST_EXPR
17347 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17348 || TREE_CODE (expression) == CAST_EXPR)
17349 return dependent_type_p (TREE_TYPE (expression));
17351 /* The types of these expressions depends only on the type created
17352 by the expression. */
17353 if (TREE_CODE (expression) == NEW_EXPR
17354 || TREE_CODE (expression) == VEC_NEW_EXPR)
17356 /* For NEW_EXPR tree nodes created inside a template, either
17357 the object type itself or a TREE_LIST may appear as the
17359 tree type = TREE_OPERAND (expression, 1);
17360 if (TREE_CODE (type) == TREE_LIST)
17361 /* This is an array type. We need to check array dimensions
17363 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17364 || value_dependent_expression_p
17365 (TREE_OPERAND (TREE_VALUE (type), 1));
17367 return dependent_type_p (type);
17370 if (TREE_CODE (expression) == SCOPE_REF
17371 && dependent_scope_ref_p (expression,
17372 type_dependent_expression_p))
17375 if (TREE_CODE (expression) == FUNCTION_DECL
17376 && DECL_LANG_SPECIFIC (expression)
17377 && DECL_TEMPLATE_INFO (expression)
17378 && (any_dependent_template_arguments_p
17379 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17382 if (TREE_CODE (expression) == TEMPLATE_DECL
17383 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17386 if (TREE_CODE (expression) == STMT_EXPR)
17387 expression = stmt_expr_value_expr (expression);
17389 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17394 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17396 if (type_dependent_expression_p (elt))
17402 if (TREE_TYPE (expression) == unknown_type_node)
17404 if (TREE_CODE (expression) == ADDR_EXPR)
17405 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17406 if (TREE_CODE (expression) == COMPONENT_REF
17407 || TREE_CODE (expression) == OFFSET_REF)
17409 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17411 expression = TREE_OPERAND (expression, 1);
17412 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17415 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17416 if (TREE_CODE (expression) == SCOPE_REF)
17419 if (TREE_CODE (expression) == BASELINK)
17420 expression = BASELINK_FUNCTIONS (expression);
17422 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17424 if (any_dependent_template_arguments_p
17425 (TREE_OPERAND (expression, 1)))
17427 expression = TREE_OPERAND (expression, 0);
17429 gcc_assert (TREE_CODE (expression) == OVERLOAD
17430 || TREE_CODE (expression) == FUNCTION_DECL);
17434 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17436 expression = OVL_NEXT (expression);
17441 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17443 return (dependent_type_p (TREE_TYPE (expression)));
17446 /* Like type_dependent_expression_p, but it also works while not processing
17447 a template definition, i.e. during substitution or mangling. */
17450 type_dependent_expression_p_push (tree expr)
17453 ++processing_template_decl;
17454 b = type_dependent_expression_p (expr);
17455 --processing_template_decl;
17459 /* Returns TRUE if ARGS contains a type-dependent expression. */
17462 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17467 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
17469 if (type_dependent_expression_p (arg))
17475 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17476 expressions) contains any value-dependent expressions. */
17479 any_value_dependent_elements_p (const_tree list)
17481 for (; list; list = TREE_CHAIN (list))
17482 if (value_dependent_expression_p (TREE_VALUE (list)))
17488 /* Returns TRUE if the ARG (a template argument) is dependent. */
17491 dependent_template_arg_p (tree arg)
17493 if (!processing_template_decl)
17496 if (TREE_CODE (arg) == TEMPLATE_DECL
17497 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17498 return dependent_template_p (arg);
17499 else if (ARGUMENT_PACK_P (arg))
17501 tree args = ARGUMENT_PACK_ARGS (arg);
17502 int i, len = TREE_VEC_LENGTH (args);
17503 for (i = 0; i < len; ++i)
17505 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17511 else if (TYPE_P (arg))
17512 return dependent_type_p (arg);
17514 return (type_dependent_expression_p (arg)
17515 || value_dependent_expression_p (arg));
17518 /* Returns true if ARGS (a collection of template arguments) contains
17519 any types that require structural equality testing. */
17522 any_template_arguments_need_structural_equality_p (tree args)
17529 if (args == error_mark_node)
17532 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17534 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17535 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17537 tree arg = TREE_VEC_ELT (level, j);
17538 tree packed_args = NULL_TREE;
17541 if (ARGUMENT_PACK_P (arg))
17543 /* Look inside the argument pack. */
17544 packed_args = ARGUMENT_PACK_ARGS (arg);
17545 len = TREE_VEC_LENGTH (packed_args);
17548 for (k = 0; k < len; ++k)
17551 arg = TREE_VEC_ELT (packed_args, k);
17553 if (error_operand_p (arg))
17555 else if (TREE_CODE (arg) == TEMPLATE_DECL
17556 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17558 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17560 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17561 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17570 /* Returns true if ARGS (a collection of template arguments) contains
17571 any dependent arguments. */
17574 any_dependent_template_arguments_p (const_tree args)
17581 if (args == error_mark_node)
17584 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17586 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17587 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17588 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17595 /* Returns TRUE if the template TMPL is dependent. */
17598 dependent_template_p (tree tmpl)
17600 if (TREE_CODE (tmpl) == OVERLOAD)
17604 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17606 tmpl = OVL_CHAIN (tmpl);
17611 /* Template template parameters are dependent. */
17612 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17613 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17615 /* So are names that have not been looked up. */
17616 if (TREE_CODE (tmpl) == SCOPE_REF
17617 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17619 /* So are member templates of dependent classes. */
17620 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17621 return dependent_type_p (DECL_CONTEXT (tmpl));
17625 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17628 dependent_template_id_p (tree tmpl, tree args)
17630 return (dependent_template_p (tmpl)
17631 || any_dependent_template_arguments_p (args));
17634 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17638 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17642 if (!processing_template_decl)
17645 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17647 tree decl = TREE_VEC_ELT (declv, i);
17648 tree init = TREE_VEC_ELT (initv, i);
17649 tree cond = TREE_VEC_ELT (condv, i);
17650 tree incr = TREE_VEC_ELT (incrv, i);
17652 if (type_dependent_expression_p (decl))
17655 if (init && type_dependent_expression_p (init))
17658 if (type_dependent_expression_p (cond))
17661 if (COMPARISON_CLASS_P (cond)
17662 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17663 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17666 if (TREE_CODE (incr) == MODOP_EXPR)
17668 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17669 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17672 else if (type_dependent_expression_p (incr))
17674 else if (TREE_CODE (incr) == MODIFY_EXPR)
17676 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17678 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17680 tree t = TREE_OPERAND (incr, 1);
17681 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17682 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17691 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17692 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17693 no such TYPE can be found. Note that this function peers inside
17694 uninstantiated templates and therefore should be used only in
17695 extremely limited situations. ONLY_CURRENT_P restricts this
17696 peering to the currently open classes hierarchy (which is required
17697 when comparing types). */
17700 resolve_typename_type (tree type, bool only_current_p)
17709 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17711 scope = TYPE_CONTEXT (type);
17712 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17713 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17714 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17715 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17716 identifier of the TYPENAME_TYPE anymore.
17717 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17718 TYPENAME_TYPE instead, we avoid messing up with a possible
17719 typedef variant case. */
17720 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17722 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17723 it first before we can figure out what NAME refers to. */
17724 if (TREE_CODE (scope) == TYPENAME_TYPE)
17725 scope = resolve_typename_type (scope, only_current_p);
17726 /* If we don't know what SCOPE refers to, then we cannot resolve the
17728 if (TREE_CODE (scope) == TYPENAME_TYPE)
17730 /* If the SCOPE is a template type parameter, we have no way of
17731 resolving the name. */
17732 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17734 /* If the SCOPE is not the current instantiation, there's no reason
17735 to look inside it. */
17736 if (only_current_p && !currently_open_class (scope))
17738 /* If this is a typedef, we don't want to look inside (c++/11987). */
17739 if (typedef_variant_p (type))
17741 /* If SCOPE isn't the template itself, it will not have a valid
17742 TYPE_FIELDS list. */
17743 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17744 /* scope is either the template itself or a compatible instantiation
17745 like X<T>, so look up the name in the original template. */
17746 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17748 /* scope is a partial instantiation, so we can't do the lookup or we
17749 will lose the template arguments. */
17751 /* Enter the SCOPE so that name lookup will be resolved as if we
17752 were in the class definition. In particular, SCOPE will no
17753 longer be considered a dependent type. */
17754 pushed_scope = push_scope (scope);
17755 /* Look up the declaration. */
17756 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17758 result = NULL_TREE;
17760 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17761 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17764 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17765 && TREE_CODE (decl) == TYPE_DECL)
17767 result = TREE_TYPE (decl);
17768 if (result == error_mark_node)
17769 result = NULL_TREE;
17771 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17772 && DECL_CLASS_TEMPLATE_P (decl))
17776 /* Obtain the template and the arguments. */
17777 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17778 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17779 /* Instantiate the template. */
17780 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17781 /*entering_scope=*/0,
17782 tf_error | tf_user);
17783 if (result == error_mark_node)
17784 result = NULL_TREE;
17787 /* Leave the SCOPE. */
17789 pop_scope (pushed_scope);
17791 /* If we failed to resolve it, return the original typename. */
17795 /* If lookup found a typename type, resolve that too. */
17796 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
17798 /* Ill-formed programs can cause infinite recursion here, so we
17799 must catch that. */
17800 TYPENAME_IS_RESOLVING_P (type) = 1;
17801 result = resolve_typename_type (result, only_current_p);
17802 TYPENAME_IS_RESOLVING_P (type) = 0;
17805 /* Qualify the resulting type. */
17806 quals = cp_type_quals (type);
17808 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
17813 /* EXPR is an expression which is not type-dependent. Return a proxy
17814 for EXPR that can be used to compute the types of larger
17815 expressions containing EXPR. */
17818 build_non_dependent_expr (tree expr)
17822 /* Preserve null pointer constants so that the type of things like
17823 "p == 0" where "p" is a pointer can be determined. */
17824 if (null_ptr_cst_p (expr))
17826 /* Preserve OVERLOADs; the functions must be available to resolve
17829 if (TREE_CODE (inner_expr) == STMT_EXPR)
17830 inner_expr = stmt_expr_value_expr (inner_expr);
17831 if (TREE_CODE (inner_expr) == ADDR_EXPR)
17832 inner_expr = TREE_OPERAND (inner_expr, 0);
17833 if (TREE_CODE (inner_expr) == COMPONENT_REF)
17834 inner_expr = TREE_OPERAND (inner_expr, 1);
17835 if (is_overloaded_fn (inner_expr)
17836 || TREE_CODE (inner_expr) == OFFSET_REF)
17838 /* There is no need to return a proxy for a variable. */
17839 if (TREE_CODE (expr) == VAR_DECL)
17841 /* Preserve string constants; conversions from string constants to
17842 "char *" are allowed, even though normally a "const char *"
17843 cannot be used to initialize a "char *". */
17844 if (TREE_CODE (expr) == STRING_CST)
17846 /* Preserve arithmetic constants, as an optimization -- there is no
17847 reason to create a new node. */
17848 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
17850 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
17851 There is at least one place where we want to know that a
17852 particular expression is a throw-expression: when checking a ?:
17853 expression, there are special rules if the second or third
17854 argument is a throw-expression. */
17855 if (TREE_CODE (expr) == THROW_EXPR)
17858 if (TREE_CODE (expr) == COND_EXPR)
17859 return build3 (COND_EXPR,
17861 TREE_OPERAND (expr, 0),
17862 (TREE_OPERAND (expr, 1)
17863 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
17864 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
17865 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
17866 if (TREE_CODE (expr) == COMPOUND_EXPR
17867 && !COMPOUND_EXPR_OVERLOADED (expr))
17868 return build2 (COMPOUND_EXPR,
17870 TREE_OPERAND (expr, 0),
17871 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
17873 /* If the type is unknown, it can't really be non-dependent */
17874 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
17876 /* Otherwise, build a NON_DEPENDENT_EXPR.
17878 REFERENCE_TYPEs are not stripped for expressions in templates
17879 because doing so would play havoc with mangling. Consider, for
17882 template <typename T> void f<T& g>() { g(); }
17884 In the body of "f", the expression for "g" will have
17885 REFERENCE_TYPE, even though the standard says that it should
17886 not. The reason is that we must preserve the syntactic form of
17887 the expression so that mangling (say) "f<g>" inside the body of
17888 "f" works out correctly. Therefore, the REFERENCE_TYPE is
17890 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
17893 /* ARGS is a vector of expressions as arguments to a function call.
17894 Replace the arguments with equivalent non-dependent expressions.
17895 This modifies ARGS in place. */
17898 make_args_non_dependent (VEC(tree,gc) *args)
17903 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
17905 tree newarg = build_non_dependent_expr (arg);
17907 VEC_replace (tree, args, ix, newarg);
17911 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
17912 with a level one deeper than the actual template parms. */
17917 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
17918 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
17919 TYPE_DECL, get_identifier ("auto"), au);
17920 TYPE_STUB_DECL (au) = TYPE_NAME (au);
17921 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
17922 (0, processing_template_decl + 1, processing_template_decl + 1,
17923 TYPE_NAME (au), NULL_TREE);
17924 TYPE_CANONICAL (au) = canonical_type_parameter (au);
17925 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
17926 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
17931 /* Given type ARG, return std::initializer_list<ARG>. */
17936 tree std_init_list = namespace_binding
17937 (get_identifier ("initializer_list"), std_node);
17939 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
17941 error ("deducing from brace-enclosed initializer list requires "
17942 "#include <initializer_list>");
17943 return error_mark_node;
17945 argvec = make_tree_vec (1);
17946 TREE_VEC_ELT (argvec, 0) = arg;
17947 return lookup_template_class (std_init_list, argvec, NULL_TREE,
17948 NULL_TREE, 0, tf_warning_or_error);
17951 /* Replace auto in TYPE with std::initializer_list<auto>. */
17954 listify_autos (tree type, tree auto_node)
17956 tree init_auto = listify (auto_node);
17957 tree argvec = make_tree_vec (1);
17958 TREE_VEC_ELT (argvec, 0) = init_auto;
17959 if (processing_template_decl)
17960 argvec = add_to_template_args (current_template_args (), argvec);
17961 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17964 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
17965 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
17968 do_auto_deduction (tree type, tree init, tree auto_node)
17970 tree parms, tparms, targs;
17974 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
17975 with either a new invented type template parameter U or, if the
17976 initializer is a braced-init-list (8.5.4), with
17977 std::initializer_list<U>. */
17978 if (BRACE_ENCLOSED_INITIALIZER_P (init))
17979 type = listify_autos (type, auto_node);
17981 parms = build_tree_list (NULL_TREE, type);
17983 tparms = make_tree_vec (1);
17984 targs = make_tree_vec (1);
17985 TREE_VEC_ELT (tparms, 0)
17986 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
17987 val = type_unification_real (tparms, targs, parms, args, 1, 0,
17988 DEDUCE_CALL, LOOKUP_NORMAL);
17991 error ("unable to deduce %qT from %qE", type, init);
17992 return error_mark_node;
17995 /* If the list of declarators contains more than one declarator, the type
17996 of each declared variable is determined as described above. If the
17997 type deduced for the template parameter U is not the same in each
17998 deduction, the program is ill-formed. */
17999 if (TREE_TYPE (auto_node)
18000 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
18002 error ("inconsistent deduction for %qT: %qT and then %qT",
18003 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
18004 return error_mark_node;
18006 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
18008 if (processing_template_decl)
18009 targs = add_to_template_args (current_template_args (), targs);
18010 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
18013 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
18017 splice_late_return_type (tree type, tree late_return_type)
18021 if (late_return_type == NULL_TREE)
18023 argvec = make_tree_vec (1);
18024 TREE_VEC_ELT (argvec, 0) = late_return_type;
18025 if (processing_template_decl)
18026 argvec = add_to_template_args (current_template_args (), argvec);
18027 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18030 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
18033 is_auto (const_tree type)
18035 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18036 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
18042 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
18043 appear as a type-specifier for the declaration in question, we don't
18044 have to look through the whole type. */
18047 type_uses_auto (tree type)
18049 enum tree_code code;
18050 if (is_auto (type))
18053 code = TREE_CODE (type);
18055 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18056 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18057 || code == METHOD_TYPE || code == ARRAY_TYPE)
18058 return type_uses_auto (TREE_TYPE (type));
18060 if (TYPE_PTRMEMFUNC_P (type))
18061 return type_uses_auto (TREE_TYPE (TREE_TYPE
18062 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18067 /* For a given template T, return the list of typedefs referenced
18068 in T for which access check is needed at T instantiation time.
18069 T is either a FUNCTION_DECL or a RECORD_TYPE.
18070 Those typedefs were added to T by the function
18071 append_type_to_template_for_access_check. */
18074 get_types_needing_access_check (tree t)
18076 tree ti, result = NULL_TREE;
18078 if (!t || t == error_mark_node)
18081 if (!(ti = get_template_info (t)))
18084 if (CLASS_TYPE_P (t)
18085 || TREE_CODE (t) == FUNCTION_DECL)
18087 if (!TI_TEMPLATE (ti))
18090 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
18096 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
18097 tied to T. That list of typedefs will be access checked at
18098 T instantiation time.
18099 T is either a FUNCTION_DECL or a RECORD_TYPE.
18100 TYPE_DECL is a TYPE_DECL node representing a typedef.
18101 SCOPE is the scope through which TYPE_DECL is accessed.
18103 This function is a subroutine of
18104 append_type_to_template_for_access_check. */
18107 append_type_to_template_for_access_check_1 (tree t,
18113 if (!t || t == error_mark_node)
18116 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
18117 || CLASS_TYPE_P (t))
18119 && TREE_CODE (type_decl) == TYPE_DECL
18122 if (!(ti = get_template_info (t)))
18125 gcc_assert (TI_TEMPLATE (ti));
18127 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti) =
18128 tree_cons (type_decl, scope, TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti));
18131 /* Append TYPE_DECL to the template TEMPL.
18132 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
18133 At TEMPL instanciation time, TYPE_DECL will be checked to see
18134 if it can be accessed through SCOPE.
18136 e.g. consider the following code snippet:
18143 template<class U> struct S
18150 At S<char> instantiation time, we need to check the access of C::myint
18151 In other words, we need to check the access of the myint typedef through
18152 the C scope. For that purpose, this function will add the myint typedef
18153 and the scope C through which its being accessed to a list of typedefs
18154 tied to the template S. That list will be walked at template instantiation
18155 time and access check performed on each typedefs it contains.
18156 Note that this particular code snippet should yield an error because
18157 myint is private to C. */
18160 append_type_to_template_for_access_check (tree templ,
18166 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
18168 /* Make sure we don't append the type to the template twice. */
18169 for (node = get_types_needing_access_check (templ);
18171 node = TREE_CHAIN (node))
18173 tree decl = TREE_PURPOSE (node);
18174 tree type_scope = TREE_VALUE (node);
18176 if (decl == type_decl && type_scope == scope)
18180 append_type_to_template_for_access_check_1 (templ, type_decl, scope);
18183 /* Set up the hash tables for template instantiations. */
18186 init_template_processing (void)
18188 decl_specializations = htab_create_ggc (37,
18189 hash_specialization,
18190 eq_specializations,
18192 type_specializations = htab_create_ggc (37,
18193 hash_specialization,
18194 eq_specializations,
18198 #include "gt-cp-pt.h"