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"
36 #include "pointer-set.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
48 #include "tree-iterator.h"
51 /* The type of functions taking a tree, and some additional data, and
53 typedef int (*tree_fn_t) (tree, void*);
55 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
56 instantiations have been deferred, either because their definitions
57 were not yet available, or because we were putting off doing the work. */
58 struct GTY (()) pending_template {
59 struct pending_template *next;
60 struct tinst_level *tinst;
63 static GTY(()) struct pending_template *pending_templates;
64 static GTY(()) struct pending_template *last_pending_template;
66 int processing_template_parmlist;
67 static int template_header_count;
69 static GTY(()) tree saved_trees;
70 static VEC(int,heap) *inline_parm_levels;
72 static GTY(()) struct tinst_level *current_tinst_level;
74 static GTY(()) tree saved_access_scope;
76 /* Live only within one (recursive) call to tsubst_expr. We use
77 this to pass the statement expression node from the STMT_EXPR
78 to the EXPR_STMT that is its result. */
79 static tree cur_stmt_expr;
81 /* A map from local variable declarations in the body of the template
82 presently being instantiated to the corresponding instantiated
84 static htab_t local_specializations;
86 typedef struct GTY(()) spec_entry
93 static GTY ((param_is (spec_entry)))
94 htab_t decl_specializations;
96 static GTY ((param_is (spec_entry)))
97 htab_t type_specializations;
99 /* Contains canonical template parameter types. The vector is indexed by
100 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
101 TREE_LIST, whose TREE_VALUEs contain the canonical template
102 parameters of various types and levels. */
103 static GTY(()) VEC(tree,gc) *canonical_template_parms;
105 #define UNIFY_ALLOW_NONE 0
106 #define UNIFY_ALLOW_MORE_CV_QUAL 1
107 #define UNIFY_ALLOW_LESS_CV_QUAL 2
108 #define UNIFY_ALLOW_DERIVED 4
109 #define UNIFY_ALLOW_INTEGER 8
110 #define UNIFY_ALLOW_OUTER_LEVEL 16
111 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
112 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
114 static void push_access_scope (tree);
115 static void pop_access_scope (tree);
116 static bool resolve_overloaded_unification (tree, tree, tree, tree,
117 unification_kind_t, int);
118 static int try_one_overload (tree, tree, tree, tree, tree,
119 unification_kind_t, int, bool);
120 static int unify (tree, tree, tree, tree, int);
121 static void add_pending_template (tree);
122 static tree reopen_tinst_level (struct tinst_level *);
123 static tree tsubst_initializer_list (tree, tree);
124 static tree get_class_bindings (tree, tree, tree);
125 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
127 static void tsubst_enum (tree, tree, tree);
128 static tree add_to_template_args (tree, tree);
129 static tree add_outermost_template_args (tree, tree);
130 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
131 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
133 static int type_unification_real (tree, tree, tree, const tree *,
134 unsigned int, int, unification_kind_t, int);
135 static void note_template_header (int);
136 static tree convert_nontype_argument_function (tree, tree);
137 static tree convert_nontype_argument (tree, tree);
138 static tree convert_template_argument (tree, tree, tree,
139 tsubst_flags_t, int, tree);
140 static int for_each_template_parm (tree, tree_fn_t, void*,
141 struct pointer_set_t*, bool);
142 static tree expand_template_argument_pack (tree);
143 static tree build_template_parm_index (int, int, int, tree, tree);
144 static bool inline_needs_template_parms (tree);
145 static void push_inline_template_parms_recursive (tree, int);
146 static tree retrieve_local_specialization (tree);
147 static void register_local_specialization (tree, tree);
148 static hashval_t hash_specialization (const void *p);
149 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
150 static int mark_template_parm (tree, void *);
151 static int template_parm_this_level_p (tree, void *);
152 static tree tsubst_friend_function (tree, tree);
153 static tree tsubst_friend_class (tree, tree);
154 static int can_complete_type_without_circularity (tree);
155 static tree get_bindings (tree, tree, tree, bool);
156 static int template_decl_level (tree);
157 static int check_cv_quals_for_unify (int, tree, tree);
158 static void template_parm_level_and_index (tree, int*, int*);
159 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
160 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
161 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
163 static void regenerate_decl_from_template (tree, tree);
164 static tree most_specialized_class (tree, tree);
165 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
166 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
167 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
168 static bool check_specialization_scope (void);
169 static tree process_partial_specialization (tree);
170 static void set_current_access_from_decl (tree);
171 static tree get_template_base (tree, tree, tree, tree);
172 static tree try_class_unification (tree, tree, tree, tree);
173 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
175 static bool template_template_parm_bindings_ok_p (tree, tree);
176 static int template_args_equal (tree, tree);
177 static void tsubst_default_arguments (tree);
178 static tree for_each_template_parm_r (tree *, int *, void *);
179 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
180 static void copy_default_args_to_explicit_spec (tree);
181 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
182 static int eq_local_specializations (const void *, const void *);
183 static bool dependent_template_arg_p (tree);
184 static bool any_template_arguments_need_structural_equality_p (tree);
185 static bool dependent_type_p_r (tree);
186 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
187 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
188 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_decl (tree, tree, tsubst_flags_t);
190 static void perform_typedefs_access_check (tree tmpl, tree targs);
191 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 /* Create a template info node. */
292 build_template_info (tree template_decl, tree template_args)
294 tree result = make_node (TEMPLATE_INFO);
295 TI_TEMPLATE (result) = template_decl;
296 TI_ARGS (result) = template_args;
300 /* Return the template info node corresponding to T, whatever T is. */
303 get_template_info (const_tree t)
305 tree tinfo = NULL_TREE;
307 if (!t || t == error_mark_node)
310 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
311 tinfo = DECL_TEMPLATE_INFO (t);
313 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
316 if (TAGGED_TYPE_P (t))
317 tinfo = TYPE_TEMPLATE_INFO (t);
318 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
319 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
324 /* Returns the template nesting level of the indicated class TYPE.
334 A<T>::B<U> has depth two, while A<T> has depth one.
335 Both A<T>::B<int> and A<int>::B<U> have depth one, if
336 they are instantiations, not specializations.
338 This function is guaranteed to return 0 if passed NULL_TREE so
339 that, for example, `template_class_depth (current_class_type)' is
343 template_class_depth (tree type)
348 type && TREE_CODE (type) != NAMESPACE_DECL;
349 type = (TREE_CODE (type) == FUNCTION_DECL)
350 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
352 tree tinfo = get_template_info (type);
354 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
355 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
362 /* Subroutine of maybe_begin_member_template_processing.
363 Returns true if processing DECL needs us to push template parms. */
366 inline_needs_template_parms (tree decl)
368 if (! DECL_TEMPLATE_INFO (decl))
371 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
372 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
375 /* Subroutine of maybe_begin_member_template_processing.
376 Push the template parms in PARMS, starting from LEVELS steps into the
377 chain, and ending at the beginning, since template parms are listed
381 push_inline_template_parms_recursive (tree parmlist, int levels)
383 tree parms = TREE_VALUE (parmlist);
387 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
389 ++processing_template_decl;
390 current_template_parms
391 = tree_cons (size_int (processing_template_decl),
392 parms, current_template_parms);
393 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
395 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
397 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
399 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
401 if (parm == error_mark_node)
404 gcc_assert (DECL_P (parm));
406 switch (TREE_CODE (parm))
415 /* Make a CONST_DECL as is done in process_template_parm.
416 It is ugly that we recreate this here; the original
417 version built in process_template_parm is no longer
419 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
420 CONST_DECL, DECL_NAME (parm),
422 DECL_ARTIFICIAL (decl) = 1;
423 TREE_CONSTANT (decl) = 1;
424 TREE_READONLY (decl) = 1;
425 DECL_INITIAL (decl) = DECL_INITIAL (parm);
426 SET_DECL_TEMPLATE_PARM_P (decl);
437 /* Restore the template parameter context for a member template or
438 a friend template defined in a class definition. */
441 maybe_begin_member_template_processing (tree decl)
446 if (inline_needs_template_parms (decl))
448 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
449 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
451 if (DECL_TEMPLATE_SPECIALIZATION (decl))
454 parms = TREE_CHAIN (parms);
457 push_inline_template_parms_recursive (parms, levels);
460 /* Remember how many levels of template parameters we pushed so that
461 we can pop them later. */
462 VEC_safe_push (int, heap, inline_parm_levels, levels);
465 /* Undo the effects of maybe_begin_member_template_processing. */
468 maybe_end_member_template_processing (void)
473 if (VEC_length (int, inline_parm_levels) == 0)
476 last = VEC_pop (int, inline_parm_levels);
477 for (i = 0; i < last; ++i)
479 --processing_template_decl;
480 current_template_parms = TREE_CHAIN (current_template_parms);
485 /* Return a new template argument vector which contains all of ARGS,
486 but has as its innermost set of arguments the EXTRA_ARGS. */
489 add_to_template_args (tree args, tree extra_args)
496 extra_depth = TMPL_ARGS_DEPTH (extra_args);
497 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
499 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
500 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
502 for (j = 1; j <= extra_depth; ++j, ++i)
503 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
508 /* Like add_to_template_args, but only the outermost ARGS are added to
509 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
510 (EXTRA_ARGS) levels are added. This function is used to combine
511 the template arguments from a partial instantiation with the
512 template arguments used to attain the full instantiation from the
513 partial instantiation. */
516 add_outermost_template_args (tree args, tree extra_args)
520 /* If there are more levels of EXTRA_ARGS than there are ARGS,
521 something very fishy is going on. */
522 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
524 /* If *all* the new arguments will be the EXTRA_ARGS, just return
526 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
529 /* For the moment, we make ARGS look like it contains fewer levels. */
530 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
532 new_args = add_to_template_args (args, extra_args);
534 /* Now, we restore ARGS to its full dimensions. */
535 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
540 /* Return the N levels of innermost template arguments from the ARGS. */
543 get_innermost_template_args (tree args, int n)
551 /* If N is 1, just return the innermost set of template arguments. */
553 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
555 /* If we're not removing anything, just return the arguments we were
557 extra_levels = TMPL_ARGS_DEPTH (args) - n;
558 gcc_assert (extra_levels >= 0);
559 if (extra_levels == 0)
562 /* Make a new set of arguments, not containing the outer arguments. */
563 new_args = make_tree_vec (n);
564 for (i = 1; i <= n; ++i)
565 SET_TMPL_ARGS_LEVEL (new_args, i,
566 TMPL_ARGS_LEVEL (args, i + extra_levels));
571 /* The inverse of get_innermost_template_args: Return all but the innermost
572 EXTRA_LEVELS levels of template arguments from the ARGS. */
575 strip_innermost_template_args (tree args, int extra_levels)
578 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
583 /* If N is 1, just return the outermost set of template arguments. */
585 return TMPL_ARGS_LEVEL (args, 1);
587 /* If we're not removing anything, just return the arguments we were
589 gcc_assert (extra_levels >= 0);
590 if (extra_levels == 0)
593 /* Make a new set of arguments, not containing the inner arguments. */
594 new_args = make_tree_vec (n);
595 for (i = 1; i <= n; ++i)
596 SET_TMPL_ARGS_LEVEL (new_args, i,
597 TMPL_ARGS_LEVEL (args, i));
602 /* We've got a template header coming up; push to a new level for storing
606 begin_template_parm_list (void)
608 /* We use a non-tag-transparent scope here, which causes pushtag to
609 put tags in this scope, rather than in the enclosing class or
610 namespace scope. This is the right thing, since we want
611 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
612 global template class, push_template_decl handles putting the
613 TEMPLATE_DECL into top-level scope. For a nested template class,
616 template <class T> struct S1 {
617 template <class T> struct S2 {};
620 pushtag contains special code to call pushdecl_with_scope on the
621 TEMPLATE_DECL for S2. */
622 begin_scope (sk_template_parms, NULL);
623 ++processing_template_decl;
624 ++processing_template_parmlist;
625 note_template_header (0);
628 /* This routine is called when a specialization is declared. If it is
629 invalid to declare a specialization here, an error is reported and
630 false is returned, otherwise this routine will return true. */
633 check_specialization_scope (void)
635 tree scope = current_scope ();
639 An explicit specialization shall be declared in the namespace of
640 which the template is a member, or, for member templates, in the
641 namespace of which the enclosing class or enclosing class
642 template is a member. An explicit specialization of a member
643 function, member class or static data member of a class template
644 shall be declared in the namespace of which the class template
646 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
648 error ("explicit specialization in non-namespace scope %qD", scope);
654 In an explicit specialization declaration for a member of a class
655 template or a member template that appears in namespace scope,
656 the member template and some of its enclosing class templates may
657 remain unspecialized, except that the declaration shall not
658 explicitly specialize a class member template if its enclosing
659 class templates are not explicitly specialized as well. */
660 if (current_template_parms)
662 error ("enclosing class templates are not explicitly specialized");
669 /* We've just seen template <>. */
672 begin_specialization (void)
674 begin_scope (sk_template_spec, NULL);
675 note_template_header (1);
676 return check_specialization_scope ();
679 /* Called at then end of processing a declaration preceded by
683 end_specialization (void)
686 reset_specialization ();
689 /* Any template <>'s that we have seen thus far are not referring to a
690 function specialization. */
693 reset_specialization (void)
695 processing_specialization = 0;
696 template_header_count = 0;
699 /* We've just seen a template header. If SPECIALIZATION is nonzero,
700 it was of the form template <>. */
703 note_template_header (int specialization)
705 processing_specialization = specialization;
706 template_header_count++;
709 /* We're beginning an explicit instantiation. */
712 begin_explicit_instantiation (void)
714 gcc_assert (!processing_explicit_instantiation);
715 processing_explicit_instantiation = true;
720 end_explicit_instantiation (void)
722 gcc_assert (processing_explicit_instantiation);
723 processing_explicit_instantiation = false;
726 /* An explicit specialization or partial specialization TMPL is being
727 declared. Check that the namespace in which the specialization is
728 occurring is permissible. Returns false iff it is invalid to
729 specialize TMPL in the current namespace. */
732 check_specialization_namespace (tree tmpl)
734 tree tpl_ns = decl_namespace_context (tmpl);
738 An explicit specialization shall be declared in the namespace of
739 which the template is a member, or, for member templates, in the
740 namespace of which the enclosing class or enclosing class
741 template is a member. An explicit specialization of a member
742 function, member class or static data member of a class template
743 shall be declared in the namespace of which the class template is
745 if (current_scope() != DECL_CONTEXT (tmpl)
746 && !at_namespace_scope_p ())
748 error ("specialization of %qD must appear at namespace scope", tmpl);
751 if (is_associated_namespace (current_namespace, tpl_ns))
752 /* Same or super-using namespace. */
756 permerror (input_location, "specialization of %qD in different namespace", tmpl);
757 permerror (input_location, " from definition of %q+#D", tmpl);
762 /* SPEC is an explicit instantiation. Check that it is valid to
763 perform this explicit instantiation in the current namespace. */
766 check_explicit_instantiation_namespace (tree spec)
770 /* DR 275: An explicit instantiation shall appear in an enclosing
771 namespace of its template. */
772 ns = decl_namespace_context (spec);
773 if (!is_ancestor (current_namespace, ns))
774 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
775 "(which does not enclose namespace %qD)",
776 spec, current_namespace, ns);
779 /* The TYPE is being declared. If it is a template type, that means it
780 is a partial specialization. Do appropriate error-checking. */
783 maybe_process_partial_specialization (tree type)
787 if (type == error_mark_node)
788 return error_mark_node;
790 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
792 error ("name of class shadows template template parameter %qD",
794 return error_mark_node;
797 context = TYPE_CONTEXT (type);
799 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
801 /* This is for ordinary explicit specialization and partial
802 specialization of a template class such as:
804 template <> class C<int>;
808 template <class T> class C<T*>;
810 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
812 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
813 && !COMPLETE_TYPE_P (type))
815 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
816 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
817 if (processing_template_decl)
819 if (push_template_decl (TYPE_MAIN_DECL (type))
821 return error_mark_node;
824 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
825 error ("specialization of %qT after instantiation", type);
827 else if (CLASS_TYPE_P (type)
828 && !CLASSTYPE_USE_TEMPLATE (type)
829 && CLASSTYPE_TEMPLATE_INFO (type)
830 && context && CLASS_TYPE_P (context)
831 && CLASSTYPE_TEMPLATE_INFO (context))
833 /* This is for an explicit specialization of member class
834 template according to [temp.expl.spec/18]:
836 template <> template <class U> class C<int>::D;
838 The context `C<int>' must be an implicit instantiation.
839 Otherwise this is just a member class template declared
842 template <> class C<int> { template <class U> class D; };
843 template <> template <class U> class C<int>::D;
845 In the first case, `C<int>::D' is a specialization of `C<T>::D'
846 while in the second case, `C<int>::D' is a primary template
847 and `C<T>::D' may not exist. */
849 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
850 && !COMPLETE_TYPE_P (type))
853 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
855 if (current_namespace
856 != decl_namespace_context (tmpl))
858 permerror (input_location, "specializing %q#T in different namespace", type);
859 permerror (input_location, " from definition of %q+#D", tmpl);
862 /* Check for invalid specialization after instantiation:
864 template <> template <> class C<int>::D<int>;
865 template <> template <class U> class C<int>::D; */
867 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
868 t; t = TREE_CHAIN (t))
870 tree inst = TREE_VALUE (t);
871 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
873 /* We already have a full specialization of this partial
874 instantiation. Reassign it to the new member
875 specialization template. */
879 elt.tmpl = most_general_template (tmpl);
880 elt.args = CLASSTYPE_TI_ARGS (inst);
883 htab_remove_elt (type_specializations, &elt);
886 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
888 slot = (spec_entry **)
889 htab_find_slot (type_specializations, &elt, INSERT);
890 *slot = GGC_NEW (spec_entry);
893 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
894 /* But if we've had an implicit instantiation, that's a
895 problem ([temp.expl.spec]/6). */
896 error ("specialization %qT after instantiation %qT",
900 /* Mark TYPE as a specialization. And as a result, we only
901 have one level of template argument for the innermost
903 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
904 CLASSTYPE_TI_ARGS (type)
905 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
908 else if (processing_specialization)
910 error ("explicit specialization of non-template %qT", type);
911 return error_mark_node;
917 /* Returns nonzero if we can optimize the retrieval of specializations
918 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
919 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
922 optimize_specialization_lookup_p (tree tmpl)
924 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
925 && DECL_CLASS_SCOPE_P (tmpl)
926 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
928 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
929 /* The optimized lookup depends on the fact that the
930 template arguments for the member function template apply
931 purely to the containing class, which is not true if the
932 containing class is an explicit or partial
934 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
935 && !DECL_MEMBER_TEMPLATE_P (tmpl)
936 && !DECL_CONV_FN_P (tmpl)
937 /* It is possible to have a template that is not a member
938 template and is not a member of a template class:
940 template <typename T>
941 struct S { friend A::f(); };
943 Here, the friend function is a template, but the context does
944 not have template information. The optimized lookup relies
945 on having ARGS be the template arguments for both the class
946 and the function template. */
947 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
950 /* Retrieve the specialization (in the sense of [temp.spec] - a
951 specialization is either an instantiation or an explicit
952 specialization) of TMPL for the given template ARGS. If there is
953 no such specialization, return NULL_TREE. The ARGS are a vector of
954 arguments, or a vector of vectors of arguments, in the case of
955 templates with more than one level of parameters.
957 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
958 then we search for a partial specialization matching ARGS. This
959 parameter is ignored if TMPL is not a class template. */
962 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
964 if (args == error_mark_node)
967 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
969 /* There should be as many levels of arguments as there are
970 levels of parameters. */
971 gcc_assert (TMPL_ARGS_DEPTH (args)
972 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
974 if (optimize_specialization_lookup_p (tmpl))
977 tree class_specialization;
978 VEC(tree,gc) *methods;
982 /* The template arguments actually apply to the containing
983 class. Find the class specialization with those
985 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
987 = retrieve_specialization (class_template, args, 0);
988 if (!class_specialization)
990 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
991 for the specialization. */
992 idx = class_method_index_for_fn (class_specialization, tmpl);
995 /* Iterate through the methods with the indicated name, looking
996 for the one that has an instance of TMPL. */
997 methods = CLASSTYPE_METHOD_VEC (class_specialization);
998 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1000 tree fn = OVL_CURRENT (fns);
1001 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1002 /* using-declarations can add base methods to the method vec,
1003 and we don't want those here. */
1004 && DECL_CONTEXT (fn) == class_specialization)
1013 htab_t specializations;
1017 elt.spec = NULL_TREE;
1019 if (DECL_CLASS_TEMPLATE_P (tmpl))
1020 specializations = type_specializations;
1022 specializations = decl_specializations;
1025 hash = hash_specialization (&elt);
1026 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1034 /* Like retrieve_specialization, but for local declarations. */
1037 retrieve_local_specialization (tree tmpl)
1041 if (local_specializations == NULL)
1044 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1045 htab_hash_pointer (tmpl));
1046 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1049 /* Returns nonzero iff DECL is a specialization of TMPL. */
1052 is_specialization_of (tree decl, tree tmpl)
1056 if (TREE_CODE (decl) == FUNCTION_DECL)
1060 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1066 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1068 for (t = TREE_TYPE (decl);
1070 t = CLASSTYPE_USE_TEMPLATE (t)
1071 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1072 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1079 /* Returns nonzero iff DECL is a specialization of friend declaration
1080 FRIEND_DECL according to [temp.friend]. */
1083 is_specialization_of_friend (tree decl, tree friend_decl)
1085 bool need_template = true;
1088 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1089 || TREE_CODE (decl) == TYPE_DECL);
1091 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1092 of a template class, we want to check if DECL is a specialization
1094 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1095 && DECL_TEMPLATE_INFO (friend_decl)
1096 && !DECL_USE_TEMPLATE (friend_decl))
1098 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1099 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1100 need_template = false;
1102 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1103 && !PRIMARY_TEMPLATE_P (friend_decl))
1104 need_template = false;
1106 /* There is nothing to do if this is not a template friend. */
1107 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1110 if (is_specialization_of (decl, friend_decl))
1114 A member of a class template may be declared to be a friend of a
1115 non-template class. In this case, the corresponding member of
1116 every specialization of the class template is a friend of the
1117 class granting friendship.
1119 For example, given a template friend declaration
1121 template <class T> friend void A<T>::f();
1123 the member function below is considered a friend
1125 template <> struct A<int> {
1129 For this type of template friend, TEMPLATE_DEPTH below will be
1130 nonzero. To determine if DECL is a friend of FRIEND, we first
1131 check if the enclosing class is a specialization of another. */
1133 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1135 && DECL_CLASS_SCOPE_P (decl)
1136 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1137 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1139 /* Next, we check the members themselves. In order to handle
1140 a few tricky cases, such as when FRIEND_DECL's are
1142 template <class T> friend void A<T>::g(T t);
1143 template <class T> template <T t> friend void A<T>::h();
1147 void A<int>::g(int);
1148 template <int> void A<int>::h();
1150 we need to figure out ARGS, the template arguments from
1151 the context of DECL. This is required for template substitution
1152 of `T' in the function parameter of `g' and template parameter
1153 of `h' in the above examples. Here ARGS corresponds to `int'. */
1155 tree context = DECL_CONTEXT (decl);
1156 tree args = NULL_TREE;
1157 int current_depth = 0;
1159 while (current_depth < template_depth)
1161 if (CLASSTYPE_TEMPLATE_INFO (context))
1163 if (current_depth == 0)
1164 args = TYPE_TI_ARGS (context);
1166 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1169 context = TYPE_CONTEXT (context);
1172 if (TREE_CODE (decl) == FUNCTION_DECL)
1177 tree friend_args_type;
1178 tree decl_args_type;
1180 /* Make sure that both DECL and FRIEND_DECL are templates or
1182 is_template = DECL_TEMPLATE_INFO (decl)
1183 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1184 if (need_template ^ is_template)
1186 else if (is_template)
1188 /* If both are templates, check template parameter list. */
1190 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1192 if (!comp_template_parms
1193 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1197 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1200 decl_type = TREE_TYPE (decl);
1202 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1203 tf_none, NULL_TREE);
1204 if (friend_type == error_mark_node)
1207 /* Check if return types match. */
1208 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1211 /* Check if function parameter types match, ignoring the
1212 `this' parameter. */
1213 friend_args_type = TYPE_ARG_TYPES (friend_type);
1214 decl_args_type = TYPE_ARG_TYPES (decl_type);
1215 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1216 friend_args_type = TREE_CHAIN (friend_args_type);
1217 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1218 decl_args_type = TREE_CHAIN (decl_args_type);
1220 return compparms (decl_args_type, friend_args_type);
1224 /* DECL is a TYPE_DECL */
1226 tree decl_type = TREE_TYPE (decl);
1228 /* Make sure that both DECL and FRIEND_DECL are templates or
1231 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1232 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1234 if (need_template ^ is_template)
1236 else if (is_template)
1239 /* If both are templates, check the name of the two
1240 TEMPLATE_DECL's first because is_friend didn't. */
1241 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1242 != DECL_NAME (friend_decl))
1245 /* Now check template parameter list. */
1247 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1249 return comp_template_parms
1250 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1254 return (DECL_NAME (decl)
1255 == DECL_NAME (friend_decl));
1261 /* Register the specialization SPEC as a specialization of TMPL with
1262 the indicated ARGS. IS_FRIEND indicates whether the specialization
1263 is actually just a friend declaration. Returns SPEC, or an
1264 equivalent prior declaration, if available. */
1267 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1271 spec_entry **slot = NULL;
1274 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1276 if (TREE_CODE (spec) == FUNCTION_DECL
1277 && uses_template_parms (DECL_TI_ARGS (spec)))
1278 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1279 register it; we want the corresponding TEMPLATE_DECL instead.
1280 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1281 the more obvious `uses_template_parms (spec)' to avoid problems
1282 with default function arguments. In particular, given
1283 something like this:
1285 template <class T> void f(T t1, T t = T())
1287 the default argument expression is not substituted for in an
1288 instantiation unless and until it is actually needed. */
1291 if (optimize_specialization_lookup_p (tmpl))
1292 /* We don't put these specializations in the hash table, but we might
1293 want to give an error about a mismatch. */
1294 fn = retrieve_specialization (tmpl, args, 0);
1302 hash = hash_specialization (&elt);
1304 slot = (spec_entry **)
1305 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1312 /* We can sometimes try to re-register a specialization that we've
1313 already got. In particular, regenerate_decl_from_template calls
1314 duplicate_decls which will update the specialization list. But,
1315 we'll still get called again here anyhow. It's more convenient
1316 to simply allow this than to try to prevent it. */
1319 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1321 if (DECL_TEMPLATE_INSTANTIATION (fn))
1323 if (DECL_ODR_USED (fn)
1324 || DECL_EXPLICIT_INSTANTIATION (fn))
1326 error ("specialization of %qD after instantiation",
1328 return error_mark_node;
1333 /* This situation should occur only if the first
1334 specialization is an implicit instantiation, the
1335 second is an explicit specialization, and the
1336 implicit instantiation has not yet been used. That
1337 situation can occur if we have implicitly
1338 instantiated a member function and then specialized
1341 We can also wind up here if a friend declaration that
1342 looked like an instantiation turns out to be a
1345 template <class T> void foo(T);
1346 class S { friend void foo<>(int) };
1347 template <> void foo(int);
1349 We transform the existing DECL in place so that any
1350 pointers to it become pointers to the updated
1353 If there was a definition for the template, but not
1354 for the specialization, we want this to look as if
1355 there were no definition, and vice versa. */
1356 DECL_INITIAL (fn) = NULL_TREE;
1357 duplicate_decls (spec, fn, is_friend);
1358 /* The call to duplicate_decls will have applied
1361 An explicit specialization of a function template
1362 is inline only if it is explicitly declared to be,
1363 and independently of whether its function template
1366 to the primary function; now copy the inline bits to
1367 the various clones. */
1368 FOR_EACH_CLONE (clone, fn)
1370 DECL_DECLARED_INLINE_P (clone)
1371 = DECL_DECLARED_INLINE_P (fn);
1372 DECL_SOURCE_LOCATION (clone)
1373 = DECL_SOURCE_LOCATION (fn);
1375 check_specialization_namespace (fn);
1380 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1382 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1383 /* Dup decl failed, but this is a new definition. Set the
1384 line number so any errors match this new
1386 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1392 return duplicate_decls (spec, fn, is_friend);
1394 /* A specialization must be declared in the same namespace as the
1395 template it is specializing. */
1396 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1397 && !check_specialization_namespace (tmpl))
1398 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1400 if (!optimize_specialization_lookup_p (tmpl))
1402 gcc_assert (tmpl && args && spec);
1403 *slot = GGC_NEW (spec_entry);
1405 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1406 && PRIMARY_TEMPLATE_P (tmpl)
1407 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1408 /* TMPL is a forward declaration of a template function; keep a list
1409 of all specializations in case we need to reassign them to a friend
1410 template later in tsubst_friend_function. */
1411 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1412 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1418 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1419 TMPL and ARGS members, ignores SPEC. */
1422 eq_specializations (const void *p1, const void *p2)
1424 const spec_entry *e1 = (const spec_entry *)p1;
1425 const spec_entry *e2 = (const spec_entry *)p2;
1427 return (e1->tmpl == e2->tmpl
1428 && comp_template_args (e1->args, e2->args));
1431 /* Returns a hash for a template TMPL and template arguments ARGS. */
1434 hash_tmpl_and_args (tree tmpl, tree args)
1436 hashval_t val = DECL_UID (tmpl);
1437 return iterative_hash_template_arg (args, val);
1440 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1444 hash_specialization (const void *p)
1446 const spec_entry *e = (const spec_entry *)p;
1447 return hash_tmpl_and_args (e->tmpl, e->args);
1450 /* Recursively calculate a hash value for a template argument ARG, for use
1451 in the hash tables of template specializations. */
1454 iterative_hash_template_arg (tree arg, hashval_t val)
1456 unsigned HOST_WIDE_INT i;
1457 enum tree_code code;
1460 if (arg == NULL_TREE)
1461 return iterative_hash_object (arg, val);
1466 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1467 /* We can get one of these when re-hashing a previous entry in the middle
1468 of substituting into a pack expansion. Just look through it. */
1469 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1471 code = TREE_CODE (arg);
1472 tclass = TREE_CODE_CLASS (code);
1474 val = iterative_hash_object (code, val);
1481 case IDENTIFIER_NODE:
1482 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1486 int i, len = TREE_VEC_LENGTH (arg);
1487 for (i = 0; i < len; ++i)
1488 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1492 case TYPE_PACK_EXPANSION:
1493 case EXPR_PACK_EXPANSION:
1494 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1496 case TYPE_ARGUMENT_PACK:
1497 case NONTYPE_ARGUMENT_PACK:
1498 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1501 for (; arg; arg = TREE_CHAIN (arg))
1502 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1506 for (; arg; arg = OVL_CHAIN (arg))
1507 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1513 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1515 val = iterative_hash_template_arg (field, val);
1516 val = iterative_hash_template_arg (value, val);
1522 if (!DECL_ARTIFICIAL (arg))
1523 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1524 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1527 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1530 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1531 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1533 case TEMPLATE_PARM_INDEX:
1534 val = iterative_hash_template_arg
1535 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1536 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1537 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1540 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1541 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1542 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1545 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1547 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1551 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1552 code = TREE_CODE (TREE_OPERAND (arg, 1));
1553 val = iterative_hash_object (code, val);
1554 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1557 /* layout_type sets structural equality for arrays of
1558 incomplete type, so we can't rely on the canonical type
1560 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1561 return iterative_hash_template_arg (TYPE_DOMAIN (arg), val);
1567 if (TYPE_CANONICAL (arg))
1568 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1570 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1571 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1572 /* Otherwise just compare the types during lookup. */
1575 case tcc_declaration:
1577 return iterative_hash_expr (arg, val);
1580 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1582 unsigned n = TREE_OPERAND_LENGTH (arg);
1583 for (i = 0; i < n; ++i)
1584 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1593 /* Unregister the specialization SPEC as a specialization of TMPL.
1594 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1595 if the SPEC was listed as a specialization of TMPL.
1597 Note that SPEC has been ggc_freed, so we can't look inside it. */
1600 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1605 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1606 elt.args = TI_ARGS (tinfo);
1607 elt.spec = NULL_TREE;
1609 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1612 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1613 gcc_assert (new_spec != NULL_TREE);
1614 (*slot)->spec = new_spec;
1621 /* Compare an entry in the local specializations hash table P1 (which
1622 is really a pointer to a TREE_LIST) with P2 (which is really a
1626 eq_local_specializations (const void *p1, const void *p2)
1628 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1631 /* Hash P1, an entry in the local specializations table. */
1634 hash_local_specialization (const void* p1)
1636 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1639 /* Like register_specialization, but for local declarations. We are
1640 registering SPEC, an instantiation of TMPL. */
1643 register_local_specialization (tree spec, tree tmpl)
1647 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1648 htab_hash_pointer (tmpl), INSERT);
1649 *slot = build_tree_list (spec, tmpl);
1652 /* TYPE is a class type. Returns true if TYPE is an explicitly
1653 specialized class. */
1656 explicit_class_specialization_p (tree type)
1658 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1660 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1663 /* Print the list of functions at FNS, going through all the overloads
1664 for each element of the list. Alternatively, FNS can not be a
1665 TREE_LIST, in which case it will be printed together with all the
1668 MORE and *STR should respectively be FALSE and NULL when the function
1669 is called from the outside. They are used internally on recursive
1670 calls. print_candidates manages the two parameters and leaves NULL
1671 in *STR when it ends. */
1674 print_candidates_1 (tree fns, bool more, const char **str)
1677 char *spaces = NULL;
1679 for (fn = fns; fn; fn = OVL_NEXT (fn))
1680 if (TREE_CODE (fn) == TREE_LIST)
1682 gcc_assert (!OVL_NEXT (fn) && !is_overloaded_fn (fn));
1683 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1684 print_candidates_1 (TREE_VALUE (fn2),
1685 TREE_CHAIN (fn2) || more, str);
1691 /* Pick the prefix string. */
1692 if (!more && !OVL_NEXT (fns))
1694 error ("candidate is: %+#D", OVL_CURRENT (fn));
1698 *str = _("candidates are:");
1699 spaces = get_spaces (*str);
1701 error ("%s %+#D", *str, OVL_CURRENT (fn));
1702 *str = spaces ? spaces : *str;
1712 /* Print the list of candidate FNS in an error message. */
1715 print_candidates (tree fns)
1717 const char *str = NULL;
1718 print_candidates_1 (fns, false, &str);
1719 gcc_assert (str == NULL);
1722 /* Returns the template (one of the functions given by TEMPLATE_ID)
1723 which can be specialized to match the indicated DECL with the
1724 explicit template args given in TEMPLATE_ID. The DECL may be
1725 NULL_TREE if none is available. In that case, the functions in
1726 TEMPLATE_ID are non-members.
1728 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1729 specialization of a member template.
1731 The TEMPLATE_COUNT is the number of references to qualifying
1732 template classes that appeared in the name of the function. See
1733 check_explicit_specialization for a more accurate description.
1735 TSK indicates what kind of template declaration (if any) is being
1736 declared. TSK_TEMPLATE indicates that the declaration given by
1737 DECL, though a FUNCTION_DECL, has template parameters, and is
1738 therefore a template function.
1740 The template args (those explicitly specified and those deduced)
1741 are output in a newly created vector *TARGS_OUT.
1743 If it is impossible to determine the result, an error message is
1744 issued. The error_mark_node is returned to indicate failure. */
1747 determine_specialization (tree template_id,
1750 int need_member_template,
1756 tree explicit_targs;
1757 tree candidates = NULL_TREE;
1758 /* A TREE_LIST of templates of which DECL may be a specialization.
1759 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1760 corresponding TREE_PURPOSE is the set of template arguments that,
1761 when used to instantiate the template, would produce a function
1762 with the signature of DECL. */
1763 tree templates = NULL_TREE;
1765 struct cp_binding_level *b;
1767 *targs_out = NULL_TREE;
1769 if (template_id == error_mark_node || decl == error_mark_node)
1770 return error_mark_node;
1772 fns = TREE_OPERAND (template_id, 0);
1773 explicit_targs = TREE_OPERAND (template_id, 1);
1775 if (fns == error_mark_node)
1776 return error_mark_node;
1778 /* Check for baselinks. */
1779 if (BASELINK_P (fns))
1780 fns = BASELINK_FUNCTIONS (fns);
1782 if (!is_overloaded_fn (fns))
1784 error ("%qD is not a function template", fns);
1785 return error_mark_node;
1788 /* Count the number of template headers specified for this
1791 for (b = current_binding_level;
1792 b->kind == sk_template_parms;
1796 for (; fns; fns = OVL_NEXT (fns))
1798 tree fn = OVL_CURRENT (fns);
1800 if (TREE_CODE (fn) == TEMPLATE_DECL)
1802 tree decl_arg_types;
1805 /* In case of explicit specialization, we need to check if
1806 the number of template headers appearing in the specialization
1807 is correct. This is usually done in check_explicit_specialization,
1808 but the check done there cannot be exhaustive when specializing
1809 member functions. Consider the following code:
1811 template <> void A<int>::f(int);
1812 template <> template <> void A<int>::f(int);
1814 Assuming that A<int> is not itself an explicit specialization
1815 already, the first line specializes "f" which is a non-template
1816 member function, whilst the second line specializes "f" which
1817 is a template member function. So both lines are syntactically
1818 correct, and check_explicit_specialization does not reject
1821 Here, we can do better, as we are matching the specialization
1822 against the declarations. We count the number of template
1823 headers, and we check if they match TEMPLATE_COUNT + 1
1824 (TEMPLATE_COUNT is the number of qualifying template classes,
1825 plus there must be another header for the member template
1828 Notice that if header_count is zero, this is not a
1829 specialization but rather a template instantiation, so there
1830 is no check we can perform here. */
1831 if (header_count && header_count != template_count + 1)
1834 /* Check that the number of template arguments at the
1835 innermost level for DECL is the same as for FN. */
1836 if (current_binding_level->kind == sk_template_parms
1837 && !current_binding_level->explicit_spec_p
1838 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1839 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1840 (current_template_parms))))
1843 /* DECL might be a specialization of FN. */
1844 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1845 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1847 /* For a non-static member function, we need to make sure
1848 that the const qualification is the same. Since
1849 get_bindings does not try to merge the "this" parameter,
1850 we must do the comparison explicitly. */
1851 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1852 && !same_type_p (TREE_VALUE (fn_arg_types),
1853 TREE_VALUE (decl_arg_types)))
1856 /* Skip the "this" parameter and, for constructors of
1857 classes with virtual bases, the VTT parameter. A
1858 full specialization of a constructor will have a VTT
1859 parameter, but a template never will. */
1861 = skip_artificial_parms_for (decl, decl_arg_types);
1863 = skip_artificial_parms_for (fn, fn_arg_types);
1865 /* Check that the number of function parameters matches.
1867 template <class T> void f(int i = 0);
1868 template <> void f<int>();
1869 The specialization f<int> is invalid but is not caught
1870 by get_bindings below. */
1871 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1874 /* Function templates cannot be specializations; there are
1875 no partial specializations of functions. Therefore, if
1876 the type of DECL does not match FN, there is no
1878 if (tsk == tsk_template)
1880 if (compparms (fn_arg_types, decl_arg_types))
1881 candidates = tree_cons (NULL_TREE, fn, candidates);
1885 /* See whether this function might be a specialization of this
1887 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1890 /* We cannot deduce template arguments that when used to
1891 specialize TMPL will produce DECL. */
1894 /* Save this template, and the arguments deduced. */
1895 templates = tree_cons (targs, fn, templates);
1897 else if (need_member_template)
1898 /* FN is an ordinary member function, and we need a
1899 specialization of a member template. */
1901 else if (TREE_CODE (fn) != FUNCTION_DECL)
1902 /* We can get IDENTIFIER_NODEs here in certain erroneous
1905 else if (!DECL_FUNCTION_MEMBER_P (fn))
1906 /* This is just an ordinary non-member function. Nothing can
1907 be a specialization of that. */
1909 else if (DECL_ARTIFICIAL (fn))
1910 /* Cannot specialize functions that are created implicitly. */
1914 tree decl_arg_types;
1916 /* This is an ordinary member function. However, since
1917 we're here, we can assume it's enclosing class is a
1918 template class. For example,
1920 template <typename T> struct S { void f(); };
1921 template <> void S<int>::f() {}
1923 Here, S<int>::f is a non-template, but S<int> is a
1924 template class. If FN has the same type as DECL, we
1925 might be in business. */
1927 if (!DECL_TEMPLATE_INFO (fn))
1928 /* Its enclosing class is an explicit specialization
1929 of a template class. This is not a candidate. */
1932 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1933 TREE_TYPE (TREE_TYPE (fn))))
1934 /* The return types differ. */
1937 /* Adjust the type of DECL in case FN is a static member. */
1938 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1939 if (DECL_STATIC_FUNCTION_P (fn)
1940 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1941 decl_arg_types = TREE_CHAIN (decl_arg_types);
1943 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1946 candidates = tree_cons (NULL_TREE, fn, candidates);
1950 if (templates && TREE_CHAIN (templates))
1956 It is possible for a specialization with a given function
1957 signature to be instantiated from more than one function
1958 template. In such cases, explicit specification of the
1959 template arguments must be used to uniquely identify the
1960 function template specialization being specialized.
1962 Note that here, there's no suggestion that we're supposed to
1963 determine which of the candidate templates is most
1964 specialized. However, we, also have:
1968 Partial ordering of overloaded function template
1969 declarations is used in the following contexts to select
1970 the function template to which a function template
1971 specialization refers:
1973 -- when an explicit specialization refers to a function
1976 So, we do use the partial ordering rules, at least for now.
1977 This extension can only serve to make invalid programs valid,
1978 so it's safe. And, there is strong anecdotal evidence that
1979 the committee intended the partial ordering rules to apply;
1980 the EDG front end has that behavior, and John Spicer claims
1981 that the committee simply forgot to delete the wording in
1982 [temp.expl.spec]. */
1983 tree tmpl = most_specialized_instantiation (templates);
1984 if (tmpl != error_mark_node)
1987 TREE_CHAIN (templates) = NULL_TREE;
1991 if (templates == NULL_TREE && candidates == NULL_TREE)
1993 error ("template-id %qD for %q+D does not match any template "
1994 "declaration", template_id, decl);
1995 if (header_count && header_count != template_count + 1)
1996 inform (input_location, "saw %d %<template<>%>, need %d for "
1997 "specializing a member function template",
1998 header_count, template_count + 1);
1999 return error_mark_node;
2001 else if ((templates && TREE_CHAIN (templates))
2002 || (candidates && TREE_CHAIN (candidates))
2003 || (templates && candidates))
2005 error ("ambiguous template specialization %qD for %q+D",
2007 candidates = chainon (candidates, templates);
2008 print_candidates (candidates);
2009 return error_mark_node;
2012 /* We have one, and exactly one, match. */
2015 tree fn = TREE_VALUE (candidates);
2016 *targs_out = copy_node (DECL_TI_ARGS (fn));
2017 /* DECL is a re-declaration or partial instantiation of a template
2019 if (TREE_CODE (fn) == TEMPLATE_DECL)
2021 /* It was a specialization of an ordinary member function in a
2023 return DECL_TI_TEMPLATE (fn);
2026 /* It was a specialization of a template. */
2027 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2028 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2030 *targs_out = copy_node (targs);
2031 SET_TMPL_ARGS_LEVEL (*targs_out,
2032 TMPL_ARGS_DEPTH (*targs_out),
2033 TREE_PURPOSE (templates));
2036 *targs_out = TREE_PURPOSE (templates);
2037 return TREE_VALUE (templates);
2040 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2041 but with the default argument values filled in from those in the
2045 copy_default_args_to_explicit_spec_1 (tree spec_types,
2048 tree new_spec_types;
2053 if (spec_types == void_list_node)
2054 return void_list_node;
2056 /* Substitute into the rest of the list. */
2058 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2059 TREE_CHAIN (tmpl_types));
2061 /* Add the default argument for this parameter. */
2062 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2063 TREE_VALUE (spec_types),
2067 /* DECL is an explicit specialization. Replicate default arguments
2068 from the template it specializes. (That way, code like:
2070 template <class T> void f(T = 3);
2071 template <> void f(double);
2074 works, as required.) An alternative approach would be to look up
2075 the correct default arguments at the call-site, but this approach
2076 is consistent with how implicit instantiations are handled. */
2079 copy_default_args_to_explicit_spec (tree decl)
2084 tree new_spec_types;
2088 tree object_type = NULL_TREE;
2089 tree in_charge = NULL_TREE;
2090 tree vtt = NULL_TREE;
2092 /* See if there's anything we need to do. */
2093 tmpl = DECL_TI_TEMPLATE (decl);
2094 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2095 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2096 if (TREE_PURPOSE (t))
2101 old_type = TREE_TYPE (decl);
2102 spec_types = TYPE_ARG_TYPES (old_type);
2104 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2106 /* Remove the this pointer, but remember the object's type for
2108 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2109 spec_types = TREE_CHAIN (spec_types);
2110 tmpl_types = TREE_CHAIN (tmpl_types);
2112 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2114 /* DECL may contain more parameters than TMPL due to the extra
2115 in-charge parameter in constructors and destructors. */
2116 in_charge = spec_types;
2117 spec_types = TREE_CHAIN (spec_types);
2119 if (DECL_HAS_VTT_PARM_P (decl))
2122 spec_types = TREE_CHAIN (spec_types);
2126 /* Compute the merged default arguments. */
2128 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2130 /* Compute the new FUNCTION_TYPE. */
2134 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2139 /* Put the in-charge parameter back. */
2140 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2141 TREE_VALUE (in_charge),
2144 new_type = build_method_type_directly (object_type,
2145 TREE_TYPE (old_type),
2149 new_type = build_function_type (TREE_TYPE (old_type),
2151 new_type = cp_build_type_attribute_variant (new_type,
2152 TYPE_ATTRIBUTES (old_type));
2153 new_type = build_exception_variant (new_type,
2154 TYPE_RAISES_EXCEPTIONS (old_type));
2155 TREE_TYPE (decl) = new_type;
2158 /* Check to see if the function just declared, as indicated in
2159 DECLARATOR, and in DECL, is a specialization of a function
2160 template. We may also discover that the declaration is an explicit
2161 instantiation at this point.
2163 Returns DECL, or an equivalent declaration that should be used
2164 instead if all goes well. Issues an error message if something is
2165 amiss. Returns error_mark_node if the error is not easily
2168 FLAGS is a bitmask consisting of the following flags:
2170 2: The function has a definition.
2171 4: The function is a friend.
2173 The TEMPLATE_COUNT is the number of references to qualifying
2174 template classes that appeared in the name of the function. For
2177 template <class T> struct S { void f(); };
2180 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2181 classes are not counted in the TEMPLATE_COUNT, so that in
2183 template <class T> struct S {};
2184 template <> struct S<int> { void f(); }
2185 template <> void S<int>::f();
2187 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2188 invalid; there should be no template <>.)
2190 If the function is a specialization, it is marked as such via
2191 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2192 is set up correctly, and it is added to the list of specializations
2193 for that template. */
2196 check_explicit_specialization (tree declarator,
2201 int have_def = flags & 2;
2202 int is_friend = flags & 4;
2203 int specialization = 0;
2204 int explicit_instantiation = 0;
2205 int member_specialization = 0;
2206 tree ctype = DECL_CLASS_CONTEXT (decl);
2207 tree dname = DECL_NAME (decl);
2212 if (!processing_specialization)
2215 tsk = tsk_excessive_parms;
2218 tsk = current_tmpl_spec_kind (template_count);
2223 if (processing_specialization)
2226 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2228 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2231 /* This could be something like:
2233 template <class T> void f(T);
2234 class S { friend void f<>(int); } */
2238 /* This case handles bogus declarations like template <>
2239 template <class T> void f<int>(); */
2241 error ("template-id %qD in declaration of primary template",
2248 case tsk_invalid_member_spec:
2249 /* The error has already been reported in
2250 check_specialization_scope. */
2251 return error_mark_node;
2253 case tsk_invalid_expl_inst:
2254 error ("template parameter list used in explicit instantiation");
2260 error ("definition provided for explicit instantiation");
2262 explicit_instantiation = 1;
2265 case tsk_excessive_parms:
2266 case tsk_insufficient_parms:
2267 if (tsk == tsk_excessive_parms)
2268 error ("too many template parameter lists in declaration of %qD",
2270 else if (template_header_count)
2271 error("too few template parameter lists in declaration of %qD", decl);
2273 error("explicit specialization of %qD must be introduced by "
2274 "%<template <>%>", decl);
2278 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2280 member_specialization = 1;
2286 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2288 /* This case handles bogus declarations like template <>
2289 template <class T> void f<int>(); */
2291 if (uses_template_parms (declarator))
2292 error ("function template partial specialization %qD "
2293 "is not allowed", declarator);
2295 error ("template-id %qD in declaration of primary template",
2300 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2301 /* This is a specialization of a member template, without
2302 specialization the containing class. Something like:
2304 template <class T> struct S {
2305 template <class U> void f (U);
2307 template <> template <class U> void S<int>::f(U) {}
2309 That's a specialization -- but of the entire template. */
2317 if (specialization || member_specialization)
2319 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2320 for (; t; t = TREE_CHAIN (t))
2321 if (TREE_PURPOSE (t))
2323 permerror (input_location,
2324 "default argument specified in explicit specialization");
2329 if (specialization || member_specialization || explicit_instantiation)
2331 tree tmpl = NULL_TREE;
2332 tree targs = NULL_TREE;
2334 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2335 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2339 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2344 /* If there is no class context, the explicit instantiation
2345 must be at namespace scope. */
2346 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2348 /* Find the namespace binding, using the declaration
2350 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2352 if (fns == error_mark_node || !is_overloaded_fn (fns))
2354 error ("%qD is not a template function", dname);
2355 fns = error_mark_node;
2359 tree fn = OVL_CURRENT (fns);
2360 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2361 CP_DECL_CONTEXT (fn)))
2362 error ("%qD is not declared in %qD",
2363 decl, current_namespace);
2367 declarator = lookup_template_function (fns, NULL_TREE);
2370 if (declarator == error_mark_node)
2371 return error_mark_node;
2373 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2375 if (!explicit_instantiation)
2376 /* A specialization in class scope. This is invalid,
2377 but the error will already have been flagged by
2378 check_specialization_scope. */
2379 return error_mark_node;
2382 /* It's not valid to write an explicit instantiation in
2385 class C { template void f(); }
2387 This case is caught by the parser. However, on
2390 template class C { void f(); };
2392 (which is invalid) we can get here. The error will be
2399 else if (ctype != NULL_TREE
2400 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2403 /* Find the list of functions in ctype that have the same
2404 name as the declared function. */
2405 tree name = TREE_OPERAND (declarator, 0);
2406 tree fns = NULL_TREE;
2409 if (constructor_name_p (name, ctype))
2411 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2413 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2414 : !CLASSTYPE_DESTRUCTORS (ctype))
2416 /* From [temp.expl.spec]:
2418 If such an explicit specialization for the member
2419 of a class template names an implicitly-declared
2420 special member function (clause _special_), the
2421 program is ill-formed.
2423 Similar language is found in [temp.explicit]. */
2424 error ("specialization of implicitly-declared special member function");
2425 return error_mark_node;
2428 name = is_constructor ? ctor_identifier : dtor_identifier;
2431 if (!DECL_CONV_FN_P (decl))
2433 idx = lookup_fnfields_1 (ctype, name);
2435 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2439 VEC(tree,gc) *methods;
2442 /* For a type-conversion operator, we cannot do a
2443 name-based lookup. We might be looking for `operator
2444 int' which will be a specialization of `operator T'.
2445 So, we find *all* the conversion operators, and then
2446 select from them. */
2449 methods = CLASSTYPE_METHOD_VEC (ctype);
2451 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2452 VEC_iterate (tree, methods, idx, ovl);
2455 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2456 /* There are no more conversion functions. */
2459 /* Glue all these conversion functions together
2460 with those we already have. */
2461 for (; ovl; ovl = OVL_NEXT (ovl))
2462 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2466 if (fns == NULL_TREE)
2468 error ("no member function %qD declared in %qT", name, ctype);
2469 return error_mark_node;
2472 TREE_OPERAND (declarator, 0) = fns;
2475 /* Figure out what exactly is being specialized at this point.
2476 Note that for an explicit instantiation, even one for a
2477 member function, we cannot tell apriori whether the
2478 instantiation is for a member template, or just a member
2479 function of a template class. Even if a member template is
2480 being instantiated, the member template arguments may be
2481 elided if they can be deduced from the rest of the
2483 tmpl = determine_specialization (declarator, decl,
2485 member_specialization,
2489 if (!tmpl || tmpl == error_mark_node)
2490 /* We couldn't figure out what this declaration was
2492 return error_mark_node;
2495 tree gen_tmpl = most_general_template (tmpl);
2497 if (explicit_instantiation)
2499 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2500 is done by do_decl_instantiation later. */
2502 int arg_depth = TMPL_ARGS_DEPTH (targs);
2503 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2505 if (arg_depth > parm_depth)
2507 /* If TMPL is not the most general template (for
2508 example, if TMPL is a friend template that is
2509 injected into namespace scope), then there will
2510 be too many levels of TARGS. Remove some of them
2515 new_targs = make_tree_vec (parm_depth);
2516 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2517 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2518 = TREE_VEC_ELT (targs, i);
2522 return instantiate_template (tmpl, targs, tf_error);
2525 /* If we thought that the DECL was a member function, but it
2526 turns out to be specializing a static member function,
2527 make DECL a static member function as well. */
2528 if (DECL_STATIC_FUNCTION_P (tmpl)
2529 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2530 revert_static_member_fn (decl);
2532 /* If this is a specialization of a member template of a
2533 template class, we want to return the TEMPLATE_DECL, not
2534 the specialization of it. */
2535 if (tsk == tsk_template)
2537 tree result = DECL_TEMPLATE_RESULT (tmpl);
2538 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2539 DECL_INITIAL (result) = NULL_TREE;
2543 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2544 DECL_SOURCE_LOCATION (result)
2545 = DECL_SOURCE_LOCATION (decl);
2546 /* We want to use the argument list specified in the
2547 definition, not in the original declaration. */
2548 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2549 for (parm = DECL_ARGUMENTS (result); parm;
2550 parm = TREE_CHAIN (parm))
2551 DECL_CONTEXT (parm) = result;
2553 return register_specialization (tmpl, gen_tmpl, targs,
2557 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2558 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2560 /* Inherit default function arguments from the template
2561 DECL is specializing. */
2562 copy_default_args_to_explicit_spec (decl);
2564 /* This specialization has the same protection as the
2565 template it specializes. */
2566 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2567 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2569 /* 7.1.1-1 [dcl.stc]
2571 A storage-class-specifier shall not be specified in an
2572 explicit specialization...
2574 The parser rejects these, so unless action is taken here,
2575 explicit function specializations will always appear with
2578 The action recommended by the C++ CWG in response to C++
2579 defect report 605 is to make the storage class and linkage
2580 of the explicit specialization match the templated function:
2582 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2584 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2586 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2587 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2589 /* This specialization has the same linkage and visibility as
2590 the function template it specializes. */
2591 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2592 if (! TREE_PUBLIC (decl))
2594 DECL_INTERFACE_KNOWN (decl) = 1;
2595 DECL_NOT_REALLY_EXTERN (decl) = 1;
2597 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2598 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2600 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2601 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2605 /* If DECL is a friend declaration, declared using an
2606 unqualified name, the namespace associated with DECL may
2607 have been set incorrectly. For example, in:
2609 template <typename T> void f(T);
2611 struct S { friend void f<int>(int); }
2614 we will have set the DECL_CONTEXT for the friend
2615 declaration to N, rather than to the global namespace. */
2616 if (DECL_NAMESPACE_SCOPE_P (decl))
2617 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2619 if (is_friend && !have_def)
2620 /* This is not really a declaration of a specialization.
2621 It's just the name of an instantiation. But, it's not
2622 a request for an instantiation, either. */
2623 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2624 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2625 /* This is indeed a specialization. In case of constructors
2626 and destructors, we need in-charge and not-in-charge
2627 versions in V3 ABI. */
2628 clone_function_decl (decl, /*update_method_vec_p=*/0);
2630 /* Register this specialization so that we can find it
2632 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2639 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2640 parameters. These are represented in the same format used for
2641 DECL_TEMPLATE_PARMS. */
2644 comp_template_parms (const_tree parms1, const_tree parms2)
2649 if (parms1 == parms2)
2652 for (p1 = parms1, p2 = parms2;
2653 p1 != NULL_TREE && p2 != NULL_TREE;
2654 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2656 tree t1 = TREE_VALUE (p1);
2657 tree t2 = TREE_VALUE (p2);
2660 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2661 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2663 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2666 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2668 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2669 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2671 /* If either of the template parameters are invalid, assume
2672 they match for the sake of error recovery. */
2673 if (parm1 == error_mark_node || parm2 == error_mark_node)
2676 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2679 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2680 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2681 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2683 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2688 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2689 /* One set of parameters has more parameters lists than the
2696 /* Determine whether PARM is a parameter pack. */
2699 template_parameter_pack_p (const_tree parm)
2701 /* Determine if we have a non-type template parameter pack. */
2702 if (TREE_CODE (parm) == PARM_DECL)
2703 return (DECL_TEMPLATE_PARM_P (parm)
2704 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2706 /* If this is a list of template parameters, we could get a
2707 TYPE_DECL or a TEMPLATE_DECL. */
2708 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2709 parm = TREE_TYPE (parm);
2711 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2712 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2713 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2716 /* Determine if T is a function parameter pack. */
2719 function_parameter_pack_p (const_tree t)
2721 if (t && TREE_CODE (t) == PARM_DECL)
2722 return FUNCTION_PARAMETER_PACK_P (t);
2726 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2727 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2730 get_function_template_decl (const_tree primary_func_tmpl_inst)
2732 if (! primary_func_tmpl_inst
2733 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2734 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2737 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2740 /* Return true iff the function parameter PARAM_DECL was expanded
2741 from the function parameter pack PACK. */
2744 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2746 if (DECL_ARTIFICIAL (param_decl)
2747 || !function_parameter_pack_p (pack))
2750 /* The parameter pack and its pack arguments have the same
2752 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2755 /* Determine whether ARGS describes a variadic template args list,
2756 i.e., one that is terminated by a template argument pack. */
2759 template_args_variadic_p (tree args)
2764 if (args == NULL_TREE)
2767 args = INNERMOST_TEMPLATE_ARGS (args);
2768 nargs = TREE_VEC_LENGTH (args);
2773 last_parm = TREE_VEC_ELT (args, nargs - 1);
2775 return ARGUMENT_PACK_P (last_parm);
2778 /* Generate a new name for the parameter pack name NAME (an
2779 IDENTIFIER_NODE) that incorporates its */
2782 make_ith_pack_parameter_name (tree name, int i)
2784 /* Munge the name to include the parameter index. */
2785 #define NUMBUF_LEN 128
2786 char numbuf[NUMBUF_LEN];
2790 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2791 newname_len = IDENTIFIER_LENGTH (name)
2792 + strlen (numbuf) + 2;
2793 newname = (char*)alloca (newname_len);
2794 snprintf (newname, newname_len,
2795 "%s#%i", IDENTIFIER_POINTER (name), i);
2796 return get_identifier (newname);
2799 /* Return true if T is a primary function
2800 or class template instantiation. */
2803 primary_template_instantiation_p (const_tree t)
2808 if (TREE_CODE (t) == FUNCTION_DECL)
2809 return DECL_LANG_SPECIFIC (t)
2810 && DECL_TEMPLATE_INSTANTIATION (t)
2811 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2812 else if (CLASS_TYPE_P (t))
2813 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2814 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2818 /* Return true if PARM is a template template parameter. */
2821 template_template_parameter_p (const_tree parm)
2823 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2826 /* Return the template parameters of T if T is a
2827 primary template instantiation, NULL otherwise. */
2830 get_primary_template_innermost_parameters (const_tree t)
2832 tree parms = NULL, template_info = NULL;
2834 if ((template_info = get_template_info (t))
2835 && primary_template_instantiation_p (t))
2836 parms = INNERMOST_TEMPLATE_PARMS
2837 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2842 /* Returns the template arguments of T if T is a template instantiation,
2846 get_template_innermost_arguments (const_tree t)
2848 tree args = NULL, template_info = NULL;
2850 if ((template_info = get_template_info (t))
2851 && TI_ARGS (template_info))
2852 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2857 /* Return the argument pack elements of T if T is a template argument pack,
2861 get_template_argument_pack_elems (const_tree t)
2863 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2864 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2867 return ARGUMENT_PACK_ARGS (t);
2870 /* Structure used to track the progress of find_parameter_packs_r. */
2871 struct find_parameter_pack_data
2873 /* TREE_LIST that will contain all of the parameter packs found by
2875 tree* parameter_packs;
2877 /* Set of AST nodes that have been visited by the traversal. */
2878 struct pointer_set_t *visited;
2881 /* Identifies all of the argument packs that occur in a template
2882 argument and appends them to the TREE_LIST inside DATA, which is a
2883 find_parameter_pack_data structure. This is a subroutine of
2884 make_pack_expansion and uses_parameter_packs. */
2886 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2889 struct find_parameter_pack_data* ppd =
2890 (struct find_parameter_pack_data*)data;
2891 bool parameter_pack_p = false;
2893 /* Identify whether this is a parameter pack or not. */
2894 switch (TREE_CODE (t))
2896 case TEMPLATE_PARM_INDEX:
2897 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2898 parameter_pack_p = true;
2901 case TEMPLATE_TYPE_PARM:
2902 case TEMPLATE_TEMPLATE_PARM:
2903 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2904 parameter_pack_p = true;
2908 if (FUNCTION_PARAMETER_PACK_P (t))
2910 /* We don't want to walk into the type of a PARM_DECL,
2911 because we don't want to see the type parameter pack. */
2913 parameter_pack_p = true;
2918 /* Not a parameter pack. */
2922 if (parameter_pack_p)
2924 /* Add this parameter pack to the list. */
2925 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2929 cp_walk_tree (&TYPE_CONTEXT (t),
2930 &find_parameter_packs_r, ppd, ppd->visited);
2932 /* This switch statement will return immediately if we don't find a
2934 switch (TREE_CODE (t))
2936 case TEMPLATE_PARM_INDEX:
2939 case BOUND_TEMPLATE_TEMPLATE_PARM:
2940 /* Check the template itself. */
2941 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2942 &find_parameter_packs_r, ppd, ppd->visited);
2943 /* Check the template arguments. */
2944 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2949 case TEMPLATE_TYPE_PARM:
2950 case TEMPLATE_TEMPLATE_PARM:
2957 if (TYPE_PTRMEMFUNC_P (t))
2963 if (TYPE_TEMPLATE_INFO (t))
2964 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
2965 &find_parameter_packs_r, ppd, ppd->visited);
2971 cp_walk_tree (&TREE_TYPE (t),
2972 &find_parameter_packs_r, ppd, ppd->visited);
2976 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2981 case TYPE_PACK_EXPANSION:
2982 case EXPR_PACK_EXPANSION:
2987 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2992 case IDENTIFIER_NODE:
2993 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3005 /* Determines if the expression or type T uses any parameter packs. */
3007 uses_parameter_packs (tree t)
3009 tree parameter_packs = NULL_TREE;
3010 struct find_parameter_pack_data ppd;
3011 ppd.parameter_packs = ¶meter_packs;
3012 ppd.visited = pointer_set_create ();
3013 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3014 pointer_set_destroy (ppd.visited);
3015 return parameter_packs != NULL_TREE;
3018 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3019 representation a base-class initializer into a parameter pack
3020 expansion. If all goes well, the resulting node will be an
3021 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3024 make_pack_expansion (tree arg)
3027 tree parameter_packs = NULL_TREE;
3028 bool for_types = false;
3029 struct find_parameter_pack_data ppd;
3031 if (!arg || arg == error_mark_node)
3034 if (TREE_CODE (arg) == TREE_LIST)
3036 /* The only time we will see a TREE_LIST here is for a base
3037 class initializer. In this case, the TREE_PURPOSE will be a
3038 _TYPE node (representing the base class expansion we're
3039 initializing) and the TREE_VALUE will be a TREE_LIST
3040 containing the initialization arguments.
3042 The resulting expansion looks somewhat different from most
3043 expansions. Rather than returning just one _EXPANSION, we
3044 return a TREE_LIST whose TREE_PURPOSE is a
3045 TYPE_PACK_EXPANSION containing the bases that will be
3046 initialized. The TREE_VALUE will be identical to the
3047 original TREE_VALUE, which is a list of arguments that will
3048 be passed to each base. We do not introduce any new pack
3049 expansion nodes into the TREE_VALUE (although it is possible
3050 that some already exist), because the TREE_PURPOSE and
3051 TREE_VALUE all need to be expanded together with the same
3052 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3053 resulting TREE_PURPOSE will mention the parameter packs in
3054 both the bases and the arguments to the bases. */
3057 tree parameter_packs = NULL_TREE;
3059 /* Determine which parameter packs will be used by the base
3061 ppd.visited = pointer_set_create ();
3062 ppd.parameter_packs = ¶meter_packs;
3063 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3066 if (parameter_packs == NULL_TREE)
3068 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3069 pointer_set_destroy (ppd.visited);
3070 return error_mark_node;
3073 if (TREE_VALUE (arg) != void_type_node)
3075 /* Collect the sets of parameter packs used in each of the
3076 initialization arguments. */
3077 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3079 /* Determine which parameter packs will be expanded in this
3081 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3086 pointer_set_destroy (ppd.visited);
3088 /* Create the pack expansion type for the base type. */
3089 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3090 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3091 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3093 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3094 they will rarely be compared to anything. */
3095 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3097 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3100 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3103 /* Build the PACK_EXPANSION_* node. */
3105 ? cxx_make_type (TYPE_PACK_EXPANSION)
3106 : make_node (EXPR_PACK_EXPANSION);
3107 SET_PACK_EXPANSION_PATTERN (result, arg);
3108 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3110 /* Propagate type and const-expression information. */
3111 TREE_TYPE (result) = TREE_TYPE (arg);
3112 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3115 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3116 they will rarely be compared to anything. */
3117 SET_TYPE_STRUCTURAL_EQUALITY (result);
3119 /* Determine which parameter packs will be expanded. */
3120 ppd.parameter_packs = ¶meter_packs;
3121 ppd.visited = pointer_set_create ();
3122 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3123 pointer_set_destroy (ppd.visited);
3125 /* Make sure we found some parameter packs. */
3126 if (parameter_packs == NULL_TREE)
3129 error ("expansion pattern %<%T%> contains no argument packs", arg);
3131 error ("expansion pattern %<%E%> contains no argument packs", arg);
3132 return error_mark_node;
3134 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3139 /* Checks T for any "bare" parameter packs, which have not yet been
3140 expanded, and issues an error if any are found. This operation can
3141 only be done on full expressions or types (e.g., an expression
3142 statement, "if" condition, etc.), because we could have expressions like:
3144 foo(f(g(h(args)))...)
3146 where "args" is a parameter pack. check_for_bare_parameter_packs
3147 should not be called for the subexpressions args, h(args),
3148 g(h(args)), or f(g(h(args))), because we would produce erroneous
3151 Returns TRUE and emits an error if there were bare parameter packs,
3152 returns FALSE otherwise. */
3154 check_for_bare_parameter_packs (tree t)
3156 tree parameter_packs = NULL_TREE;
3157 struct find_parameter_pack_data ppd;
3159 if (!processing_template_decl || !t || t == error_mark_node)
3162 if (TREE_CODE (t) == TYPE_DECL)
3165 ppd.parameter_packs = ¶meter_packs;
3166 ppd.visited = pointer_set_create ();
3167 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3168 pointer_set_destroy (ppd.visited);
3170 if (parameter_packs)
3172 error ("parameter packs not expanded with %<...%>:");
3173 while (parameter_packs)
3175 tree pack = TREE_VALUE (parameter_packs);
3176 tree name = NULL_TREE;
3178 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3179 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3180 name = TYPE_NAME (pack);
3181 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3182 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3184 name = DECL_NAME (pack);
3187 inform (input_location, " %qD", name);
3189 inform (input_location, " <anonymous>");
3191 parameter_packs = TREE_CHAIN (parameter_packs);
3200 /* Expand any parameter packs that occur in the template arguments in
3203 expand_template_argument_pack (tree args)
3205 tree result_args = NULL_TREE;
3206 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3207 int num_result_args = -1;
3208 int non_default_args_count = -1;
3210 /* First, determine if we need to expand anything, and the number of
3211 slots we'll need. */
3212 for (in_arg = 0; in_arg < nargs; ++in_arg)
3214 tree arg = TREE_VEC_ELT (args, in_arg);
3215 if (arg == NULL_TREE)
3217 if (ARGUMENT_PACK_P (arg))
3219 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3220 if (num_result_args < 0)
3221 num_result_args = in_arg + num_packed;
3223 num_result_args += num_packed;
3227 if (num_result_args >= 0)
3232 /* If no expansion is necessary, we're done. */
3233 if (num_result_args < 0)
3236 /* Expand arguments. */
3237 result_args = make_tree_vec (num_result_args);
3238 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3239 non_default_args_count =
3240 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3241 for (in_arg = 0; in_arg < nargs; ++in_arg)
3243 tree arg = TREE_VEC_ELT (args, in_arg);
3244 if (ARGUMENT_PACK_P (arg))
3246 tree packed = ARGUMENT_PACK_ARGS (arg);
3247 int i, num_packed = TREE_VEC_LENGTH (packed);
3248 for (i = 0; i < num_packed; ++i, ++out_arg)
3249 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3250 if (non_default_args_count > 0)
3251 non_default_args_count += num_packed;
3255 TREE_VEC_ELT (result_args, out_arg) = arg;
3259 if (non_default_args_count >= 0)
3260 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3264 /* Checks if DECL shadows a template parameter.
3266 [temp.local]: A template-parameter shall not be redeclared within its
3267 scope (including nested scopes).
3269 Emits an error and returns TRUE if the DECL shadows a parameter,
3270 returns FALSE otherwise. */
3273 check_template_shadow (tree decl)
3277 /* If we're not in a template, we can't possibly shadow a template
3279 if (!current_template_parms)
3282 /* Figure out what we're shadowing. */
3283 if (TREE_CODE (decl) == OVERLOAD)
3284 decl = OVL_CURRENT (decl);
3285 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3287 /* If there's no previous binding for this name, we're not shadowing
3288 anything, let alone a template parameter. */
3292 /* If we're not shadowing a template parameter, we're done. Note
3293 that OLDDECL might be an OVERLOAD (or perhaps even an
3294 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3296 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3299 /* We check for decl != olddecl to avoid bogus errors for using a
3300 name inside a class. We check TPFI to avoid duplicate errors for
3301 inline member templates. */
3303 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3306 error ("declaration of %q+#D", decl);
3307 error (" shadows template parm %q+#D", olddecl);
3311 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3312 ORIG_LEVEL, DECL, and TYPE. */
3315 build_template_parm_index (int index,
3321 tree t = make_node (TEMPLATE_PARM_INDEX);
3322 TEMPLATE_PARM_IDX (t) = index;
3323 TEMPLATE_PARM_LEVEL (t) = level;
3324 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3325 TEMPLATE_PARM_DECL (t) = decl;
3326 TREE_TYPE (t) = type;
3327 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3328 TREE_READONLY (t) = TREE_READONLY (decl);
3333 /* Find the canonical type parameter for the given template type
3334 parameter. Returns the canonical type parameter, which may be TYPE
3335 if no such parameter existed. */
3337 canonical_type_parameter (tree type)
3340 int idx = TEMPLATE_TYPE_IDX (type);
3341 if (!canonical_template_parms)
3342 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3344 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3345 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3347 list = VEC_index (tree, canonical_template_parms, idx);
3348 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3349 list = TREE_CHAIN (list);
3352 return TREE_VALUE (list);
3355 VEC_replace(tree, canonical_template_parms, idx,
3356 tree_cons (NULL_TREE, type,
3357 VEC_index (tree, canonical_template_parms, idx)));
3362 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3363 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3364 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3365 new one is created. */
3368 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3369 tsubst_flags_t complain)
3371 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3372 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3373 != TEMPLATE_PARM_LEVEL (index) - levels)
3374 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3376 tree orig_decl = TEMPLATE_PARM_DECL (index);
3379 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3380 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3381 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3382 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3383 DECL_ARTIFICIAL (decl) = 1;
3384 SET_DECL_TEMPLATE_PARM_P (decl);
3386 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3387 TEMPLATE_PARM_LEVEL (index) - levels,
3388 TEMPLATE_PARM_ORIG_LEVEL (index),
3390 TEMPLATE_PARM_DESCENDANTS (index) = t;
3391 TEMPLATE_PARM_PARAMETER_PACK (t)
3392 = TEMPLATE_PARM_PARAMETER_PACK (index);
3394 /* Template template parameters need this. */
3395 if (TREE_CODE (decl) == TEMPLATE_DECL)
3396 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3397 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3401 return TEMPLATE_PARM_DESCENDANTS (index);
3404 /* Process information from new template parameter PARM and append it to the
3405 LIST being built. This new parameter is a non-type parameter iff
3406 IS_NON_TYPE is true. This new parameter is a parameter
3407 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3411 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3412 bool is_parameter_pack)
3419 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3420 defval = TREE_PURPOSE (parm);
3424 tree p = tree_last (list);
3426 if (p && TREE_VALUE (p) != error_mark_node)
3429 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3430 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3432 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3442 parm = TREE_VALUE (parm);
3444 SET_DECL_TEMPLATE_PARM_P (parm);
3446 if (TREE_TYPE (parm) == error_mark_node)
3448 err_parm_list = build_tree_list (defval, parm);
3449 TREE_VALUE (err_parm_list) = error_mark_node;
3450 return chainon (list, err_parm_list);
3456 The top-level cv-qualifiers on the template-parameter are
3457 ignored when determining its type. */
3458 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3459 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3461 err_parm_list = build_tree_list (defval, parm);
3462 TREE_VALUE (err_parm_list) = error_mark_node;
3463 return chainon (list, err_parm_list);
3466 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3468 /* This template parameter is not a parameter pack, but it
3469 should be. Complain about "bare" parameter packs. */
3470 check_for_bare_parameter_packs (TREE_TYPE (parm));
3472 /* Recover by calling this a parameter pack. */
3473 is_parameter_pack = true;
3477 /* A template parameter is not modifiable. */
3478 TREE_CONSTANT (parm) = 1;
3479 TREE_READONLY (parm) = 1;
3480 decl = build_decl (parm_loc,
3481 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3482 TREE_CONSTANT (decl) = 1;
3483 TREE_READONLY (decl) = 1;
3484 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3485 = build_template_parm_index (idx, processing_template_decl,
3486 processing_template_decl,
3487 decl, TREE_TYPE (parm));
3489 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3490 = is_parameter_pack;
3495 parm = TREE_VALUE (TREE_VALUE (parm));
3497 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3499 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3500 /* This is for distinguishing between real templates and template
3501 template parameters */
3502 TREE_TYPE (parm) = t;
3503 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3508 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3509 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3510 decl = build_decl (parm_loc,
3511 TYPE_DECL, parm, t);
3514 TYPE_NAME (t) = decl;
3515 TYPE_STUB_DECL (t) = decl;
3517 TEMPLATE_TYPE_PARM_INDEX (t)
3518 = build_template_parm_index (idx, processing_template_decl,
3519 processing_template_decl,
3520 decl, TREE_TYPE (parm));
3521 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3522 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3524 DECL_ARTIFICIAL (decl) = 1;
3525 SET_DECL_TEMPLATE_PARM_P (decl);
3527 parm = build_tree_list (defval, parm);
3528 return chainon (list, parm);
3531 /* The end of a template parameter list has been reached. Process the
3532 tree list into a parameter vector, converting each parameter into a more
3533 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3537 end_template_parm_list (tree parms)
3541 tree saved_parmlist = make_tree_vec (list_length (parms));
3543 current_template_parms
3544 = tree_cons (size_int (processing_template_decl),
3545 saved_parmlist, current_template_parms);
3547 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3549 next = TREE_CHAIN (parm);
3550 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3551 TREE_CHAIN (parm) = NULL_TREE;
3554 --processing_template_parmlist;
3556 return saved_parmlist;
3559 /* end_template_decl is called after a template declaration is seen. */
3562 end_template_decl (void)
3564 reset_specialization ();
3566 if (! processing_template_decl)
3569 /* This matches the pushlevel in begin_template_parm_list. */
3572 --processing_template_decl;
3573 current_template_parms = TREE_CHAIN (current_template_parms);
3576 /* Within the declaration of a template, return all levels of template
3577 parameters that apply. The template parameters are represented as
3578 a TREE_VEC, in the form documented in cp-tree.h for template
3582 current_template_args (void)
3585 tree args = NULL_TREE;
3586 int length = TMPL_PARMS_DEPTH (current_template_parms);
3589 /* If there is only one level of template parameters, we do not
3590 create a TREE_VEC of TREE_VECs. Instead, we return a single
3591 TREE_VEC containing the arguments. */
3593 args = make_tree_vec (length);
3595 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3597 tree a = copy_node (TREE_VALUE (header));
3600 TREE_TYPE (a) = NULL_TREE;
3601 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3603 tree t = TREE_VEC_ELT (a, i);
3605 /* T will be a list if we are called from within a
3606 begin/end_template_parm_list pair, but a vector directly
3607 if within a begin/end_member_template_processing pair. */
3608 if (TREE_CODE (t) == TREE_LIST)
3612 if (!error_operand_p (t))
3614 if (TREE_CODE (t) == TYPE_DECL
3615 || TREE_CODE (t) == TEMPLATE_DECL)
3619 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3621 /* Turn this argument into a TYPE_ARGUMENT_PACK
3622 with a single element, which expands T. */
3623 tree vec = make_tree_vec (1);
3624 #ifdef ENABLE_CHECKING
3625 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3626 (vec, TREE_VEC_LENGTH (vec));
3628 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3630 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3631 SET_ARGUMENT_PACK_ARGS (t, vec);
3636 t = DECL_INITIAL (t);
3638 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3640 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3641 with a single element, which expands T. */
3642 tree vec = make_tree_vec (1);
3643 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3644 #ifdef ENABLE_CHECKING
3645 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3646 (vec, TREE_VEC_LENGTH (vec));
3648 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3650 t = make_node (NONTYPE_ARGUMENT_PACK);
3651 SET_ARGUMENT_PACK_ARGS (t, vec);
3652 TREE_TYPE (t) = type;
3655 TREE_VEC_ELT (a, i) = t;
3660 #ifdef ENABLE_CHECKING
3661 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
3665 TREE_VEC_ELT (args, --l) = a;
3673 /* Update the declared TYPE by doing any lookups which were thought to be
3674 dependent, but are not now that we know the SCOPE of the declarator. */
3677 maybe_update_decl_type (tree orig_type, tree scope)
3679 tree type = orig_type;
3681 if (type == NULL_TREE)
3684 if (TREE_CODE (orig_type) == TYPE_DECL)
3685 type = TREE_TYPE (type);
3687 if (scope && TYPE_P (scope) && dependent_type_p (scope)
3688 && dependent_type_p (type)
3689 /* Don't bother building up the args in this case. */
3690 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
3692 /* tsubst in the args corresponding to the template parameters,
3693 including auto if present. Most things will be unchanged, but
3694 make_typename_type and tsubst_qualified_id will resolve
3695 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
3696 tree args = current_template_args ();
3697 tree auto_node = type_uses_auto (type);
3700 tree auto_vec = make_tree_vec (1);
3701 TREE_VEC_ELT (auto_vec, 0) = auto_node;
3702 args = add_to_template_args (args, auto_vec);
3705 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
3709 if (type == error_mark_node)
3712 if (TREE_CODE (orig_type) == TYPE_DECL)
3714 if (same_type_p (type, TREE_TYPE (orig_type)))
3717 type = TYPE_NAME (type);
3722 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3723 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3724 a member template. Used by push_template_decl below. */
3727 build_template_decl (tree decl, tree parms, bool member_template_p)
3729 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3730 DECL_TEMPLATE_PARMS (tmpl) = parms;
3731 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3732 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3737 struct template_parm_data
3739 /* The level of the template parameters we are currently
3743 /* The index of the specialization argument we are currently
3747 /* An array whose size is the number of template parameters. The
3748 elements are nonzero if the parameter has been used in any one
3749 of the arguments processed so far. */
3752 /* An array whose size is the number of template arguments. The
3753 elements are nonzero if the argument makes use of template
3754 parameters of this level. */
3755 int* arg_uses_template_parms;
3758 /* Subroutine of push_template_decl used to see if each template
3759 parameter in a partial specialization is used in the explicit
3760 argument list. If T is of the LEVEL given in DATA (which is
3761 treated as a template_parm_data*), then DATA->PARMS is marked
3765 mark_template_parm (tree t, void* data)
3769 struct template_parm_data* tpd = (struct template_parm_data*) data;
3771 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3773 level = TEMPLATE_PARM_LEVEL (t);
3774 idx = TEMPLATE_PARM_IDX (t);
3778 level = TEMPLATE_TYPE_LEVEL (t);
3779 idx = TEMPLATE_TYPE_IDX (t);
3782 if (level == tpd->level)
3784 tpd->parms[idx] = 1;
3785 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3788 /* Return zero so that for_each_template_parm will continue the
3789 traversal of the tree; we want to mark *every* template parm. */
3793 /* Process the partial specialization DECL. */
3796 process_partial_specialization (tree decl)
3798 tree type = TREE_TYPE (decl);
3799 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3800 tree specargs = CLASSTYPE_TI_ARGS (type);
3801 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3802 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3804 int nargs = TREE_VEC_LENGTH (inner_args);
3807 int did_error_intro = 0;
3808 struct template_parm_data tpd;
3809 struct template_parm_data tpd2;
3811 gcc_assert (current_template_parms);
3813 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3814 ntparms = TREE_VEC_LENGTH (inner_parms);
3816 /* We check that each of the template parameters given in the
3817 partial specialization is used in the argument list to the
3818 specialization. For example:
3820 template <class T> struct S;
3821 template <class T> struct S<T*>;
3823 The second declaration is OK because `T*' uses the template
3824 parameter T, whereas
3826 template <class T> struct S<int>;
3828 is no good. Even trickier is:
3839 The S2<T> declaration is actually invalid; it is a
3840 full-specialization. Of course,
3843 struct S2<T (*)(U)>;
3845 or some such would have been OK. */
3846 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3847 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3848 memset (tpd.parms, 0, sizeof (int) * ntparms);
3850 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3851 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3852 for (i = 0; i < nargs; ++i)
3854 tpd.current_arg = i;
3855 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3856 &mark_template_parm,
3859 /*include_nondeduced_p=*/false);
3861 for (i = 0; i < ntparms; ++i)
3862 if (tpd.parms[i] == 0)
3864 /* One of the template parms was not used in the
3866 if (!did_error_intro)
3868 error ("template parameters not used in partial specialization:");
3869 did_error_intro = 1;
3872 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3875 /* [temp.class.spec]
3877 The argument list of the specialization shall not be identical to
3878 the implicit argument list of the primary template. */
3879 if (comp_template_args
3881 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3883 error ("partial specialization %qT does not specialize any template arguments", type);
3885 /* [temp.class.spec]
3887 A partially specialized non-type argument expression shall not
3888 involve template parameters of the partial specialization except
3889 when the argument expression is a simple identifier.
3891 The type of a template parameter corresponding to a specialized
3892 non-type argument shall not be dependent on a parameter of the
3895 Also, we verify that pack expansions only occur at the
3896 end of the argument list. */
3897 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3899 for (i = 0; i < nargs; ++i)
3901 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3902 tree arg = TREE_VEC_ELT (inner_args, i);
3903 tree packed_args = NULL_TREE;
3906 if (ARGUMENT_PACK_P (arg))
3908 /* Extract the arguments from the argument pack. We'll be
3909 iterating over these in the following loop. */
3910 packed_args = ARGUMENT_PACK_ARGS (arg);
3911 len = TREE_VEC_LENGTH (packed_args);
3914 for (j = 0; j < len; j++)
3917 /* Get the Jth argument in the parameter pack. */
3918 arg = TREE_VEC_ELT (packed_args, j);
3920 if (PACK_EXPANSION_P (arg))
3922 /* Pack expansions must come at the end of the
3924 if ((packed_args && j < len - 1)
3925 || (!packed_args && i < nargs - 1))
3927 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3928 error ("parameter pack argument %qE must be at the "
3929 "end of the template argument list", arg);
3931 error ("parameter pack argument %qT must be at the "
3932 "end of the template argument list", arg);
3936 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3937 /* We only care about the pattern. */
3938 arg = PACK_EXPANSION_PATTERN (arg);
3940 if (/* These first two lines are the `non-type' bit. */
3942 && TREE_CODE (arg) != TEMPLATE_DECL
3943 /* This next line is the `argument expression is not just a
3944 simple identifier' condition and also the `specialized
3945 non-type argument' bit. */
3946 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3948 if ((!packed_args && tpd.arg_uses_template_parms[i])
3949 || (packed_args && uses_template_parms (arg)))
3950 error ("template argument %qE involves template parameter(s)",
3954 /* Look at the corresponding template parameter,
3955 marking which template parameters its type depends
3957 tree type = TREE_TYPE (parm);
3961 /* We haven't yet initialized TPD2. Do so now. */
3962 tpd2.arg_uses_template_parms
3963 = (int *) alloca (sizeof (int) * nargs);
3964 /* The number of parameters here is the number in the
3965 main template, which, as checked in the assertion
3967 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3969 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3972 /* Mark the template parameters. But this time, we're
3973 looking for the template parameters of the main
3974 template, not in the specialization. */
3975 tpd2.current_arg = i;
3976 tpd2.arg_uses_template_parms[i] = 0;
3977 memset (tpd2.parms, 0, sizeof (int) * nargs);
3978 for_each_template_parm (type,
3979 &mark_template_parm,
3982 /*include_nondeduced_p=*/false);
3984 if (tpd2.arg_uses_template_parms [i])
3986 /* The type depended on some template parameters.
3987 If they are fully specialized in the
3988 specialization, that's OK. */
3990 for (j = 0; j < nargs; ++j)
3991 if (tpd2.parms[j] != 0
3992 && tpd.arg_uses_template_parms [j])
3994 error ("type %qT of template argument %qE depends "
3995 "on template parameter(s)",
4006 /* We should only get here once. */
4007 gcc_assert (!COMPLETE_TYPE_P (type));
4009 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4010 = tree_cons (specargs, inner_parms,
4011 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4012 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4016 /* Check that a template declaration's use of default arguments and
4017 parameter packs is not invalid. Here, PARMS are the template
4018 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4019 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4023 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4024 declaration (but not a definition); 1 indicates a declaration, 2
4025 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4026 emitted for extraneous default arguments.
4028 Returns TRUE if there were no errors found, FALSE otherwise. */
4031 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4032 int is_partial, int is_friend_decl)
4035 int last_level_to_check;
4037 bool no_errors = true;
4041 A default template-argument shall not be specified in a
4042 function template declaration or a function template definition, nor
4043 in the template-parameter-list of the definition of a member of a
4046 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4047 /* You can't have a function template declaration in a local
4048 scope, nor you can you define a member of a class template in a
4052 if (current_class_type
4053 && !TYPE_BEING_DEFINED (current_class_type)
4054 && DECL_LANG_SPECIFIC (decl)
4055 && DECL_DECLARES_FUNCTION_P (decl)
4056 /* If this is either a friend defined in the scope of the class
4057 or a member function. */
4058 && (DECL_FUNCTION_MEMBER_P (decl)
4059 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4060 : DECL_FRIEND_CONTEXT (decl)
4061 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4063 /* And, if it was a member function, it really was defined in
4064 the scope of the class. */
4065 && (!DECL_FUNCTION_MEMBER_P (decl)
4066 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4067 /* We already checked these parameters when the template was
4068 declared, so there's no need to do it again now. This function
4069 was defined in class scope, but we're processing it's body now
4070 that the class is complete. */
4073 /* Core issue 226 (C++0x only): the following only applies to class
4075 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4079 If a template-parameter has a default template-argument, all
4080 subsequent template-parameters shall have a default
4081 template-argument supplied. */
4082 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4084 tree inner_parms = TREE_VALUE (parm_level);
4085 int ntparms = TREE_VEC_LENGTH (inner_parms);
4086 int seen_def_arg_p = 0;
4089 for (i = 0; i < ntparms; ++i)
4091 tree parm = TREE_VEC_ELT (inner_parms, i);
4093 if (parm == error_mark_node)
4096 if (TREE_PURPOSE (parm))
4098 else if (seen_def_arg_p
4099 && !template_parameter_pack_p (TREE_VALUE (parm)))
4101 error ("no default argument for %qD", TREE_VALUE (parm));
4102 /* For better subsequent error-recovery, we indicate that
4103 there should have been a default argument. */
4104 TREE_PURPOSE (parm) = error_mark_node;
4110 /* Don't complain about an enclosing partial
4112 && parm_level == parms
4113 && TREE_CODE (decl) == TYPE_DECL
4115 && template_parameter_pack_p (TREE_VALUE (parm)))
4117 /* A primary class template can only have one
4118 parameter pack, at the end of the template
4121 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4122 error ("parameter pack %qE must be at the end of the"
4123 " template parameter list", TREE_VALUE (parm));
4125 error ("parameter pack %qT must be at the end of the"
4126 " template parameter list",
4127 TREE_TYPE (TREE_VALUE (parm)));
4129 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4137 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4141 /* For an ordinary class template, default template arguments are
4142 allowed at the innermost level, e.g.:
4143 template <class T = int>
4145 but, in a partial specialization, they're not allowed even
4146 there, as we have in [temp.class.spec]:
4148 The template parameter list of a specialization shall not
4149 contain default template argument values.
4151 So, for a partial specialization, or for a function template
4152 (in C++98/C++03), we look at all of them. */
4155 /* But, for a primary class template that is not a partial
4156 specialization we look at all template parameters except the
4158 parms = TREE_CHAIN (parms);
4160 /* Figure out what error message to issue. */
4161 if (is_friend_decl == 2)
4162 msg = G_("default template arguments may not be used in function template "
4163 "friend re-declaration");
4164 else if (is_friend_decl)
4165 msg = G_("default template arguments may not be used in function template "
4166 "friend declarations");
4167 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4168 msg = G_("default template arguments may not be used in function templates "
4169 "without -std=c++0x or -std=gnu++0x");
4170 else if (is_partial)
4171 msg = G_("default template arguments may not be used in "
4172 "partial specializations");
4174 msg = G_("default argument for template parameter for class enclosing %qD");
4176 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4177 /* If we're inside a class definition, there's no need to
4178 examine the parameters to the class itself. On the one
4179 hand, they will be checked when the class is defined, and,
4180 on the other, default arguments are valid in things like:
4181 template <class T = double>
4182 struct S { template <class U> void f(U); };
4183 Here the default argument for `S' has no bearing on the
4184 declaration of `f'. */
4185 last_level_to_check = template_class_depth (current_class_type) + 1;
4187 /* Check everything. */
4188 last_level_to_check = 0;
4190 for (parm_level = parms;
4191 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4192 parm_level = TREE_CHAIN (parm_level))
4194 tree inner_parms = TREE_VALUE (parm_level);
4198 ntparms = TREE_VEC_LENGTH (inner_parms);
4199 for (i = 0; i < ntparms; ++i)
4201 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4204 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4209 if (is_friend_decl == 2)
4216 /* Clear out the default argument so that we are not
4218 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4222 /* At this point, if we're still interested in issuing messages,
4223 they must apply to classes surrounding the object declared. */
4225 msg = G_("default argument for template parameter for class "
4232 /* Worker for push_template_decl_real, called via
4233 for_each_template_parm. DATA is really an int, indicating the
4234 level of the parameters we are interested in. If T is a template
4235 parameter of that level, return nonzero. */
4238 template_parm_this_level_p (tree t, void* data)
4240 int this_level = *(int *)data;
4243 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4244 level = TEMPLATE_PARM_LEVEL (t);
4246 level = TEMPLATE_TYPE_LEVEL (t);
4247 return level == this_level;
4250 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4251 parameters given by current_template_args, or reuses a
4252 previously existing one, if appropriate. Returns the DECL, or an
4253 equivalent one, if it is replaced via a call to duplicate_decls.
4255 If IS_FRIEND is true, DECL is a friend declaration. */
4258 push_template_decl_real (tree decl, bool is_friend)
4266 int new_template_p = 0;
4267 /* True if the template is a member template, in the sense of
4269 bool member_template_p = false;
4271 if (decl == error_mark_node || !current_template_parms)
4272 return error_mark_node;
4274 /* See if this is a partial specialization. */
4275 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4276 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4277 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4279 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4283 /* For a friend, we want the context of the friend function, not
4284 the type of which it is a friend. */
4285 ctx = DECL_CONTEXT (decl);
4286 else if (CP_DECL_CONTEXT (decl)
4287 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4288 /* In the case of a virtual function, we want the class in which
4290 ctx = CP_DECL_CONTEXT (decl);
4292 /* Otherwise, if we're currently defining some class, the DECL
4293 is assumed to be a member of the class. */
4294 ctx = current_scope ();
4296 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4299 if (!DECL_CONTEXT (decl))
4300 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4302 /* See if this is a primary template. */
4303 if (is_friend && ctx)
4304 /* A friend template that specifies a class context, i.e.
4305 template <typename T> friend void A<T>::f();
4309 primary = template_parm_scope_p ();
4313 if (DECL_CLASS_SCOPE_P (decl))
4314 member_template_p = true;
4315 if (TREE_CODE (decl) == TYPE_DECL
4316 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4318 error ("template class without a name");
4319 return error_mark_node;
4321 else if (TREE_CODE (decl) == FUNCTION_DECL)
4323 if (DECL_DESTRUCTOR_P (decl))
4327 A destructor shall not be a member template. */
4328 error ("destructor %qD declared as member template", decl);
4329 return error_mark_node;
4331 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4332 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4333 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4334 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4335 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4336 == void_list_node)))
4338 /* [basic.stc.dynamic.allocation]
4340 An allocation function can be a function
4341 template. ... Template allocation functions shall
4342 have two or more parameters. */
4343 error ("invalid template declaration of %qD", decl);
4344 return error_mark_node;
4347 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4348 && CLASS_TYPE_P (TREE_TYPE (decl)))
4352 error ("template declaration of %q#D", decl);
4353 return error_mark_node;
4357 /* Check to see that the rules regarding the use of default
4358 arguments are not being violated. */
4359 check_default_tmpl_args (decl, current_template_parms,
4360 primary, is_partial, /*is_friend_decl=*/0);
4362 /* Ensure that there are no parameter packs in the type of this
4363 declaration that have not been expanded. */
4364 if (TREE_CODE (decl) == FUNCTION_DECL)
4366 /* Check each of the arguments individually to see if there are
4367 any bare parameter packs. */
4368 tree type = TREE_TYPE (decl);
4369 tree arg = DECL_ARGUMENTS (decl);
4370 tree argtype = TYPE_ARG_TYPES (type);
4372 while (arg && argtype)
4374 if (!FUNCTION_PARAMETER_PACK_P (arg)
4375 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4377 /* This is a PARM_DECL that contains unexpanded parameter
4378 packs. We have already complained about this in the
4379 check_for_bare_parameter_packs call, so just replace
4380 these types with ERROR_MARK_NODE. */
4381 TREE_TYPE (arg) = error_mark_node;
4382 TREE_VALUE (argtype) = error_mark_node;
4385 arg = TREE_CHAIN (arg);
4386 argtype = TREE_CHAIN (argtype);
4389 /* Check for bare parameter packs in the return type and the
4390 exception specifiers. */
4391 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4392 /* Errors were already issued, set return type to int
4393 as the frontend doesn't expect error_mark_node as
4395 TREE_TYPE (type) = integer_type_node;
4396 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4397 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4399 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4401 TREE_TYPE (decl) = error_mark_node;
4402 return error_mark_node;
4406 return process_partial_specialization (decl);
4408 args = current_template_args ();
4411 || TREE_CODE (ctx) == FUNCTION_DECL
4412 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4413 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4415 if (DECL_LANG_SPECIFIC (decl)
4416 && DECL_TEMPLATE_INFO (decl)
4417 && DECL_TI_TEMPLATE (decl))
4418 tmpl = DECL_TI_TEMPLATE (decl);
4419 /* If DECL is a TYPE_DECL for a class-template, then there won't
4420 be DECL_LANG_SPECIFIC. The information equivalent to
4421 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4422 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4423 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4424 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4426 /* Since a template declaration already existed for this
4427 class-type, we must be redeclaring it here. Make sure
4428 that the redeclaration is valid. */
4429 redeclare_class_template (TREE_TYPE (decl),
4430 current_template_parms);
4431 /* We don't need to create a new TEMPLATE_DECL; just use the
4432 one we already had. */
4433 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4437 tmpl = build_template_decl (decl, current_template_parms,
4441 if (DECL_LANG_SPECIFIC (decl)
4442 && DECL_TEMPLATE_SPECIALIZATION (decl))
4444 /* A specialization of a member template of a template
4446 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4447 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4448 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4454 tree a, t, current, parms;
4456 tree tinfo = get_template_info (decl);
4460 error ("template definition of non-template %q#D", decl);
4461 return error_mark_node;
4464 tmpl = TI_TEMPLATE (tinfo);
4466 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4467 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4468 && DECL_TEMPLATE_SPECIALIZATION (decl)
4469 && DECL_MEMBER_TEMPLATE_P (tmpl))
4473 /* The declaration is a specialization of a member
4474 template, declared outside the class. Therefore, the
4475 innermost template arguments will be NULL, so we
4476 replace them with the arguments determined by the
4477 earlier call to check_explicit_specialization. */
4478 args = DECL_TI_ARGS (decl);
4481 = build_template_decl (decl, current_template_parms,
4483 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4484 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4485 DECL_TI_TEMPLATE (decl) = new_tmpl;
4486 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4487 DECL_TEMPLATE_INFO (new_tmpl)
4488 = build_template_info (tmpl, args);
4490 register_specialization (new_tmpl,
4491 most_general_template (tmpl),
4497 /* Make sure the template headers we got make sense. */
4499 parms = DECL_TEMPLATE_PARMS (tmpl);
4500 i = TMPL_PARMS_DEPTH (parms);
4501 if (TMPL_ARGS_DEPTH (args) != i)
4503 error ("expected %d levels of template parms for %q#D, got %d",
4504 i, decl, TMPL_ARGS_DEPTH (args));
4507 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4509 a = TMPL_ARGS_LEVEL (args, i);
4510 t = INNERMOST_TEMPLATE_PARMS (parms);
4512 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4514 if (current == decl)
4515 error ("got %d template parameters for %q#D",
4516 TREE_VEC_LENGTH (a), decl);
4518 error ("got %d template parameters for %q#T",
4519 TREE_VEC_LENGTH (a), current);
4520 error (" but %d required", TREE_VEC_LENGTH (t));
4521 return error_mark_node;
4524 if (current == decl)
4527 current = (TYPE_P (current)
4528 ? TYPE_CONTEXT (current)
4529 : DECL_CONTEXT (current));
4532 /* Check that the parms are used in the appropriate qualifying scopes
4533 in the declarator. */
4534 if (!comp_template_args
4536 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4539 template arguments to %qD do not match original template %qD",
4540 decl, DECL_TEMPLATE_RESULT (tmpl));
4541 if (!uses_template_parms (TI_ARGS (tinfo)))
4542 inform (input_location, "use template<> for an explicit specialization");
4543 /* Avoid crash in import_export_decl. */
4544 DECL_INTERFACE_KNOWN (decl) = 1;
4545 return error_mark_node;
4549 DECL_TEMPLATE_RESULT (tmpl) = decl;
4550 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4552 /* Push template declarations for global functions and types. Note
4553 that we do not try to push a global template friend declared in a
4554 template class; such a thing may well depend on the template
4555 parameters of the class. */
4556 if (new_template_p && !ctx
4557 && !(is_friend && template_class_depth (current_class_type) > 0))
4559 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4560 if (tmpl == error_mark_node)
4561 return error_mark_node;
4563 /* Hide template friend classes that haven't been declared yet. */
4564 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4566 DECL_ANTICIPATED (tmpl) = 1;
4567 DECL_FRIEND_P (tmpl) = 1;
4573 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4576 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4577 if (DECL_CONV_FN_P (tmpl))
4579 int depth = TMPL_PARMS_DEPTH (parms);
4581 /* It is a conversion operator. See if the type converted to
4582 depends on innermost template operands. */
4584 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4586 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4589 /* Give template template parms a DECL_CONTEXT of the template
4590 for which they are a parameter. */
4591 parms = INNERMOST_TEMPLATE_PARMS (parms);
4592 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4594 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4595 if (TREE_CODE (parm) == TEMPLATE_DECL)
4596 DECL_CONTEXT (parm) = tmpl;
4598 if (TREE_CODE (TREE_TYPE (parm)) == TEMPLATE_TYPE_PARM)
4599 DECL_CONTEXT (TYPE_NAME (TREE_TYPE (parm))) = tmpl;
4603 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4604 back to its most general template. If TMPL is a specialization,
4605 ARGS may only have the innermost set of arguments. Add the missing
4606 argument levels if necessary. */
4607 if (DECL_TEMPLATE_INFO (tmpl))
4608 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4610 info = build_template_info (tmpl, args);
4612 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4613 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4614 else if (DECL_LANG_SPECIFIC (decl))
4615 DECL_TEMPLATE_INFO (decl) = info;
4617 return DECL_TEMPLATE_RESULT (tmpl);
4621 push_template_decl (tree decl)
4623 return push_template_decl_real (decl, false);
4626 /* Called when a class template TYPE is redeclared with the indicated
4627 template PARMS, e.g.:
4629 template <class T> struct S;
4630 template <class T> struct S {}; */
4633 redeclare_class_template (tree type, tree parms)
4639 if (!TYPE_TEMPLATE_INFO (type))
4641 error ("%qT is not a template type", type);
4645 tmpl = TYPE_TI_TEMPLATE (type);
4646 if (!PRIMARY_TEMPLATE_P (tmpl))
4647 /* The type is nested in some template class. Nothing to worry
4648 about here; there are no new template parameters for the nested
4654 error ("template specifiers not specified in declaration of %qD",
4659 parms = INNERMOST_TEMPLATE_PARMS (parms);
4660 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4662 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4664 error ("redeclared with %d template parameter(s)",
4665 TREE_VEC_LENGTH (parms));
4666 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4667 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4671 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4678 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4679 || TREE_VEC_ELT (parms, i) == error_mark_node)
4682 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4683 if (tmpl_parm == error_mark_node)
4686 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4687 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4688 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4690 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4692 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4693 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4694 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4695 || (TREE_CODE (tmpl_parm) != PARM_DECL
4696 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4697 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4698 || (TREE_CODE (tmpl_parm) == PARM_DECL
4699 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4700 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
4702 error ("template parameter %q+#D", tmpl_parm);
4703 error ("redeclared here as %q#D", parm);
4707 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4709 /* We have in [temp.param]:
4711 A template-parameter may not be given default arguments
4712 by two different declarations in the same scope. */
4713 error_at (input_location, "redefinition of default argument for %q#D", parm);
4714 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4715 "original definition appeared here");
4719 if (parm_default != NULL_TREE)
4720 /* Update the previous template parameters (which are the ones
4721 that will really count) with the new default value. */
4722 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4723 else if (tmpl_default != NULL_TREE)
4724 /* Update the new parameters, too; they'll be used as the
4725 parameters for any members. */
4726 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4732 /* Simplify EXPR if it is a non-dependent expression. Returns the
4733 (possibly simplified) expression. */
4736 fold_non_dependent_expr (tree expr)
4738 if (expr == NULL_TREE)
4741 /* If we're in a template, but EXPR isn't value dependent, simplify
4742 it. We're supposed to treat:
4744 template <typename T> void f(T[1 + 1]);
4745 template <typename T> void f(T[2]);
4747 as two declarations of the same function, for example. */
4748 if (processing_template_decl
4749 && !type_dependent_expression_p (expr)
4750 && !value_dependent_expression_p (expr))
4752 HOST_WIDE_INT saved_processing_template_decl;
4754 saved_processing_template_decl = processing_template_decl;
4755 processing_template_decl = 0;
4756 expr = tsubst_copy_and_build (expr,
4759 /*in_decl=*/NULL_TREE,
4760 /*function_p=*/false,
4761 /*integral_constant_expression_p=*/true);
4762 processing_template_decl = saved_processing_template_decl;
4767 /* EXPR is an expression which is used in a constant-expression context.
4768 For instance, it could be a VAR_DECL with a constant initializer.
4769 Extract the innermost constant expression.
4771 This is basically a more powerful version of
4772 integral_constant_value, which can be used also in templates where
4773 initializers can maintain a syntactic rather than semantic form
4774 (even if they are non-dependent, for access-checking purposes). */
4777 fold_decl_constant_value (tree expr)
4779 tree const_expr = expr;
4782 expr = fold_non_dependent_expr (const_expr);
4783 const_expr = integral_constant_value (expr);
4785 while (expr != const_expr);
4790 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4791 must be a function or a pointer-to-function type, as specified
4792 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4793 and check that the resulting function has external linkage. */
4796 convert_nontype_argument_function (tree type, tree expr)
4801 fn = instantiate_type (type, fns, tf_none);
4802 if (fn == error_mark_node)
4803 return error_mark_node;
4806 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4807 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4808 if (TREE_CODE (fn_no_ptr) == BASELINK)
4809 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4811 /* [temp.arg.nontype]/1
4813 A template-argument for a non-type, non-template template-parameter
4816 -- the address of an object or function with external linkage. */
4817 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4819 error ("%qE is not a valid template argument for type %qT "
4820 "because function %qD has not external linkage",
4821 expr, type, fn_no_ptr);
4828 /* Subroutine of convert_nontype_argument.
4829 Check if EXPR of type TYPE is a valid pointer-to-member constant.
4830 Emit an error otherwise. */
4833 check_valid_ptrmem_cst_expr (tree type, tree expr)
4836 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
4838 error ("%qE is not a valid template argument for type %qT",
4840 error ("it must be a pointer-to-member of the form `&X::Y'");
4844 /* Attempt to convert the non-type template parameter EXPR to the
4845 indicated TYPE. If the conversion is successful, return the
4846 converted value. If the conversion is unsuccessful, return
4847 NULL_TREE if we issued an error message, or error_mark_node if we
4848 did not. We issue error messages for out-and-out bad template
4849 parameters, but not simply because the conversion failed, since we
4850 might be just trying to do argument deduction. Both TYPE and EXPR
4851 must be non-dependent.
4853 The conversion follows the special rules described in
4854 [temp.arg.nontype], and it is much more strict than an implicit
4857 This function is called twice for each template argument (see
4858 lookup_template_class for a more accurate description of this
4859 problem). This means that we need to handle expressions which
4860 are not valid in a C++ source, but can be created from the
4861 first call (for instance, casts to perform conversions). These
4862 hacks can go away after we fix the double coercion problem. */
4865 convert_nontype_argument (tree type, tree expr)
4869 /* Detect immediately string literals as invalid non-type argument.
4870 This special-case is not needed for correctness (we would easily
4871 catch this later), but only to provide better diagnostic for this
4872 common user mistake. As suggested by DR 100, we do not mention
4873 linkage issues in the diagnostic as this is not the point. */
4874 if (TREE_CODE (expr) == STRING_CST)
4876 error ("%qE is not a valid template argument for type %qT "
4877 "because string literals can never be used in this context",
4882 /* If we are in a template, EXPR may be non-dependent, but still
4883 have a syntactic, rather than semantic, form. For example, EXPR
4884 might be a SCOPE_REF, rather than the VAR_DECL to which the
4885 SCOPE_REF refers. Preserving the qualifying scope is necessary
4886 so that access checking can be performed when the template is
4887 instantiated -- but here we need the resolved form so that we can
4888 convert the argument. */
4889 expr = fold_non_dependent_expr (expr);
4890 if (error_operand_p (expr))
4891 return error_mark_node;
4892 expr_type = TREE_TYPE (expr);
4894 /* HACK: Due to double coercion, we can get a
4895 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4896 which is the tree that we built on the first call (see
4897 below when coercing to reference to object or to reference to
4898 function). We just strip everything and get to the arg.
4899 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4901 if (TREE_CODE (expr) == NOP_EXPR)
4903 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4905 /* ??? Maybe we could use convert_from_reference here, but we
4906 would need to relax its constraints because the NOP_EXPR
4907 could actually change the type to something more cv-qualified,
4908 and this is not folded by convert_from_reference. */
4909 tree addr = TREE_OPERAND (expr, 0);
4910 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4911 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4912 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4913 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4914 (TREE_TYPE (expr_type),
4915 TREE_TYPE (TREE_TYPE (addr))));
4917 expr = TREE_OPERAND (addr, 0);
4918 expr_type = TREE_TYPE (expr);
4921 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4922 parameter is a pointer to object, through decay and
4923 qualification conversion. Let's strip everything. */
4924 else if (TYPE_PTROBV_P (type))
4927 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4928 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4929 /* Skip the ADDR_EXPR only if it is part of the decay for
4930 an array. Otherwise, it is part of the original argument
4931 in the source code. */
4932 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4933 expr = TREE_OPERAND (expr, 0);
4934 expr_type = TREE_TYPE (expr);
4938 /* [temp.arg.nontype]/5, bullet 1
4940 For a non-type template-parameter of integral or enumeration type,
4941 integral promotions (_conv.prom_) and integral conversions
4942 (_conv.integral_) are applied. */
4943 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4945 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4946 return error_mark_node;
4948 expr = fold_decl_constant_value (expr);
4949 /* Notice that there are constant expressions like '4 % 0' which
4950 do not fold into integer constants. */
4951 if (TREE_CODE (expr) != INTEGER_CST)
4953 error ("%qE is not a valid template argument for type %qT "
4954 "because it is a non-constant expression", expr, type);
4958 /* At this point, an implicit conversion does what we want,
4959 because we already know that the expression is of integral
4961 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4962 if (expr == error_mark_node)
4963 return error_mark_node;
4965 /* Conversion was allowed: fold it to a bare integer constant. */
4968 /* [temp.arg.nontype]/5, bullet 2
4970 For a non-type template-parameter of type pointer to object,
4971 qualification conversions (_conv.qual_) and the array-to-pointer
4972 conversion (_conv.array_) are applied. */
4973 else if (TYPE_PTROBV_P (type))
4975 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4977 A template-argument for a non-type, non-template template-parameter
4978 shall be one of: [...]
4980 -- the name of a non-type template-parameter;
4981 -- the address of an object or function with external linkage, [...]
4982 expressed as "& id-expression" where the & is optional if the name
4983 refers to a function or array, or if the corresponding
4984 template-parameter is a reference.
4986 Here, we do not care about functions, as they are invalid anyway
4987 for a parameter of type pointer-to-object. */
4989 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4990 /* Non-type template parameters are OK. */
4992 else if (TREE_CODE (expr) != ADDR_EXPR
4993 && TREE_CODE (expr_type) != ARRAY_TYPE)
4995 if (TREE_CODE (expr) == VAR_DECL)
4997 error ("%qD is not a valid template argument "
4998 "because %qD is a variable, not the address of "
5003 /* Other values, like integer constants, might be valid
5004 non-type arguments of some other type. */
5005 return error_mark_node;
5011 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5012 ? TREE_OPERAND (expr, 0) : expr);
5013 if (TREE_CODE (decl) != VAR_DECL)
5015 error ("%qE is not a valid template argument of type %qT "
5016 "because %qE is not a variable",
5020 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
5022 error ("%qE is not a valid template argument of type %qT "
5023 "because %qD does not have external linkage",
5029 expr = decay_conversion (expr);
5030 if (expr == error_mark_node)
5031 return error_mark_node;
5033 expr = perform_qualification_conversions (type, expr);
5034 if (expr == error_mark_node)
5035 return error_mark_node;
5037 /* [temp.arg.nontype]/5, bullet 3
5039 For a non-type template-parameter of type reference to object, no
5040 conversions apply. The type referred to by the reference may be more
5041 cv-qualified than the (otherwise identical) type of the
5042 template-argument. The template-parameter is bound directly to the
5043 template-argument, which must be an lvalue. */
5044 else if (TYPE_REF_OBJ_P (type))
5046 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5048 return error_mark_node;
5050 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5052 error ("%qE is not a valid template argument for type %qT "
5053 "because of conflicts in cv-qualification", expr, type);
5057 if (!real_lvalue_p (expr))
5059 error ("%qE is not a valid template argument for type %qT "
5060 "because it is not an lvalue", expr, type);
5064 /* [temp.arg.nontype]/1
5066 A template-argument for a non-type, non-template template-parameter
5067 shall be one of: [...]
5069 -- the address of an object or function with external linkage. */
5070 if (TREE_CODE (expr) == INDIRECT_REF
5071 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5073 expr = TREE_OPERAND (expr, 0);
5076 error ("%q#D is not a valid template argument for type %qT "
5077 "because a reference variable does not have a constant "
5078 "address", expr, type);
5085 error ("%qE is not a valid template argument for type %qT "
5086 "because it is not an object with external linkage",
5091 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5093 error ("%qE is not a valid template argument for type %qT "
5094 "because object %qD has not external linkage",
5099 expr = build_nop (type, build_address (expr));
5101 /* [temp.arg.nontype]/5, bullet 4
5103 For a non-type template-parameter of type pointer to function, only
5104 the function-to-pointer conversion (_conv.func_) is applied. If the
5105 template-argument represents a set of overloaded functions (or a
5106 pointer to such), the matching function is selected from the set
5108 else if (TYPE_PTRFN_P (type))
5110 /* If the argument is a template-id, we might not have enough
5111 context information to decay the pointer. */
5112 if (!type_unknown_p (expr_type))
5114 expr = decay_conversion (expr);
5115 if (expr == error_mark_node)
5116 return error_mark_node;
5119 expr = convert_nontype_argument_function (type, expr);
5120 if (!expr || expr == error_mark_node)
5123 if (TREE_CODE (expr) != ADDR_EXPR)
5125 error ("%qE is not a valid template argument for type %qT", expr, type);
5126 error ("it must be the address of a function with external linkage");
5130 /* [temp.arg.nontype]/5, bullet 5
5132 For a non-type template-parameter of type reference to function, no
5133 conversions apply. If the template-argument represents a set of
5134 overloaded functions, the matching function is selected from the set
5136 else if (TYPE_REFFN_P (type))
5138 if (TREE_CODE (expr) == ADDR_EXPR)
5140 error ("%qE is not a valid template argument for type %qT "
5141 "because it is a pointer", expr, type);
5142 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5146 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5147 if (!expr || expr == error_mark_node)
5150 expr = build_nop (type, build_address (expr));
5152 /* [temp.arg.nontype]/5, bullet 6
5154 For a non-type template-parameter of type pointer to member function,
5155 no conversions apply. If the template-argument represents a set of
5156 overloaded member functions, the matching member function is selected
5157 from the set (_over.over_). */
5158 else if (TYPE_PTRMEMFUNC_P (type))
5160 expr = instantiate_type (type, expr, tf_none);
5161 if (expr == error_mark_node)
5162 return error_mark_node;
5164 /* [temp.arg.nontype] bullet 1 says the pointer to member
5165 expression must be a pointer-to-member constant. */
5166 if (!check_valid_ptrmem_cst_expr (type, expr))
5167 return error_mark_node;
5169 /* There is no way to disable standard conversions in
5170 resolve_address_of_overloaded_function (called by
5171 instantiate_type). It is possible that the call succeeded by
5172 converting &B::I to &D::I (where B is a base of D), so we need
5173 to reject this conversion here.
5175 Actually, even if there was a way to disable standard conversions,
5176 it would still be better to reject them here so that we can
5177 provide a superior diagnostic. */
5178 if (!same_type_p (TREE_TYPE (expr), type))
5180 error ("%qE is not a valid template argument for type %qT "
5181 "because it is of type %qT", expr, type,
5183 /* If we are just one standard conversion off, explain. */
5184 if (can_convert (type, TREE_TYPE (expr)))
5185 inform (input_location,
5186 "standard conversions are not allowed in this context");
5190 /* [temp.arg.nontype]/5, bullet 7
5192 For a non-type template-parameter of type pointer to data member,
5193 qualification conversions (_conv.qual_) are applied. */
5194 else if (TYPE_PTRMEM_P (type))
5196 /* [temp.arg.nontype] bullet 1 says the pointer to member
5197 expression must be a pointer-to-member constant. */
5198 if (!check_valid_ptrmem_cst_expr (type, expr))
5199 return error_mark_node;
5201 expr = perform_qualification_conversions (type, expr);
5202 if (expr == error_mark_node)
5205 /* A template non-type parameter must be one of the above. */
5209 /* Sanity check: did we actually convert the argument to the
5211 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
5215 /* Subroutine of coerce_template_template_parms, which returns 1 if
5216 PARM_PARM and ARG_PARM match using the rule for the template
5217 parameters of template template parameters. Both PARM and ARG are
5218 template parameters; the rest of the arguments are the same as for
5219 coerce_template_template_parms.
5222 coerce_template_template_parm (tree parm,
5224 tsubst_flags_t complain,
5228 if (arg == NULL_TREE || arg == error_mark_node
5229 || parm == NULL_TREE || parm == error_mark_node)
5232 if (TREE_CODE (arg) != TREE_CODE (parm))
5235 switch (TREE_CODE (parm))
5238 /* We encounter instantiations of templates like
5239 template <template <template <class> class> class TT>
5242 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5243 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5245 if (!coerce_template_template_parms
5246 (parmparm, argparm, complain, in_decl, outer_args))
5252 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5253 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5254 /* Argument is a parameter pack but parameter is not. */
5259 /* The tsubst call is used to handle cases such as
5261 template <int> class C {};
5262 template <class T, template <T> class TT> class D {};
5265 i.e. the parameter list of TT depends on earlier parameters. */
5266 if (!uses_template_parms (TREE_TYPE (arg))
5268 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5272 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5273 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5274 /* Argument is a parameter pack but parameter is not. */
5287 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5288 template template parameters. Both PARM_PARMS and ARG_PARMS are
5289 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5292 Consider the example:
5293 template <class T> class A;
5294 template<template <class U> class TT> class B;
5296 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5297 the parameters to A, and OUTER_ARGS contains A. */
5300 coerce_template_template_parms (tree parm_parms,
5302 tsubst_flags_t complain,
5306 int nparms, nargs, i;
5310 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5311 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5313 nparms = TREE_VEC_LENGTH (parm_parms);
5314 nargs = TREE_VEC_LENGTH (arg_parms);
5316 /* Determine whether we have a parameter pack at the end of the
5317 template template parameter's template parameter list. */
5318 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5320 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5322 if (parm == error_mark_node)
5325 switch (TREE_CODE (parm))
5329 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5334 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5344 && !(variadic_p && nargs >= nparms - 1))
5347 /* Check all of the template parameters except the parameter pack at
5348 the end (if any). */
5349 for (i = 0; i < nparms - variadic_p; ++i)
5351 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5352 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5355 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5356 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5358 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5366 /* Check each of the template parameters in the template
5367 argument against the template parameter pack at the end of
5368 the template template parameter. */
5369 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5372 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5374 for (; i < nargs; ++i)
5376 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5379 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5381 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5390 /* Verifies that the deduced template arguments (in TARGS) for the
5391 template template parameters (in TPARMS) represent valid bindings,
5392 by comparing the template parameter list of each template argument
5393 to the template parameter list of its corresponding template
5394 template parameter, in accordance with DR150. This
5395 routine can only be called after all template arguments have been
5396 deduced. It will return TRUE if all of the template template
5397 parameter bindings are okay, FALSE otherwise. */
5399 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5401 int i, ntparms = TREE_VEC_LENGTH (tparms);
5404 /* We're dealing with template parms in this process. */
5405 ++processing_template_decl;
5407 targs = INNERMOST_TEMPLATE_ARGS (targs);
5409 for (i = 0; i < ntparms; ++i)
5411 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5412 tree targ = TREE_VEC_ELT (targs, i);
5414 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5416 tree packed_args = NULL_TREE;
5419 if (ARGUMENT_PACK_P (targ))
5421 /* Look inside the argument pack. */
5422 packed_args = ARGUMENT_PACK_ARGS (targ);
5423 len = TREE_VEC_LENGTH (packed_args);
5426 for (idx = 0; idx < len; ++idx)
5428 tree targ_parms = NULL_TREE;
5431 /* Extract the next argument from the argument
5433 targ = TREE_VEC_ELT (packed_args, idx);
5435 if (PACK_EXPANSION_P (targ))
5436 /* Look at the pattern of the pack expansion. */
5437 targ = PACK_EXPANSION_PATTERN (targ);
5439 /* Extract the template parameters from the template
5441 if (TREE_CODE (targ) == TEMPLATE_DECL)
5442 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5443 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5444 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5446 /* Verify that we can coerce the template template
5447 parameters from the template argument to the template
5448 parameter. This requires an exact match. */
5450 && !coerce_template_template_parms
5451 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5466 --processing_template_decl;
5470 /* Convert the indicated template ARG as necessary to match the
5471 indicated template PARM. Returns the converted ARG, or
5472 error_mark_node if the conversion was unsuccessful. Error and
5473 warning messages are issued under control of COMPLAIN. This
5474 conversion is for the Ith parameter in the parameter list. ARGS is
5475 the full set of template arguments deduced so far. */
5478 convert_template_argument (tree parm,
5481 tsubst_flags_t complain,
5487 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5489 if (TREE_CODE (arg) == TREE_LIST
5490 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5492 /* The template argument was the name of some
5493 member function. That's usually
5494 invalid, but static members are OK. In any
5495 case, grab the underlying fields/functions
5496 and issue an error later if required. */
5497 orig_arg = TREE_VALUE (arg);
5498 TREE_TYPE (arg) = unknown_type_node;
5503 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5504 requires_type = (TREE_CODE (parm) == TYPE_DECL
5505 || requires_tmpl_type);
5507 /* When determining whether an argument pack expansion is a template,
5508 look at the pattern. */
5509 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5510 arg = PACK_EXPANSION_PATTERN (arg);
5512 /* Deal with an injected-class-name used as a template template arg. */
5513 if (requires_tmpl_type && CLASS_TYPE_P (arg))
5515 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
5516 if (TREE_CODE (t) == TEMPLATE_DECL)
5518 if (complain & tf_warning_or_error)
5519 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
5520 " used as template template argument", TYPE_NAME (arg));
5521 else if (flag_pedantic_errors)
5529 ((TREE_CODE (arg) == TEMPLATE_DECL
5530 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5531 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5532 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5535 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5536 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5537 arg = TYPE_STUB_DECL (arg);
5539 is_type = TYPE_P (arg) || is_tmpl_type;
5541 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5542 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5544 permerror (input_location, "to refer to a type member of a template parameter, "
5545 "use %<typename %E%>", orig_arg);
5547 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5548 TREE_OPERAND (arg, 1),
5550 complain & tf_error);
5554 if (is_type != requires_type)
5558 if (complain & tf_error)
5560 error ("type/value mismatch at argument %d in template "
5561 "parameter list for %qD",
5564 error (" expected a constant of type %qT, got %qT",
5566 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5567 else if (requires_tmpl_type)
5568 error (" expected a class template, got %qE", orig_arg);
5570 error (" expected a type, got %qE", orig_arg);
5573 return error_mark_node;
5575 if (is_tmpl_type ^ requires_tmpl_type)
5577 if (in_decl && (complain & tf_error))
5579 error ("type/value mismatch at argument %d in template "
5580 "parameter list for %qD",
5583 error (" expected a type, got %qT", DECL_NAME (arg));
5585 error (" expected a class template, got %qT", orig_arg);
5587 return error_mark_node;
5592 if (requires_tmpl_type)
5594 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5595 /* The number of argument required is not known yet.
5596 Just accept it for now. */
5597 val = TREE_TYPE (arg);
5600 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5603 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5605 if (coerce_template_template_parms (parmparm, argparm,
5611 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5613 if (val != error_mark_node)
5615 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5616 val = TREE_TYPE (val);
5617 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
5618 val = make_pack_expansion (val);
5623 if (in_decl && (complain & tf_error))
5625 error ("type/value mismatch at argument %d in "
5626 "template parameter list for %qD",
5628 error (" expected a template of type %qD, got %qT",
5632 val = error_mark_node;
5638 /* We only form one instance of each template specialization.
5639 Therefore, if we use a non-canonical variant (i.e., a
5640 typedef), any future messages referring to the type will use
5641 the typedef, which is confusing if those future uses do not
5642 themselves also use the typedef. */
5644 val = strip_typedefs (val);
5648 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5650 if (invalid_nontype_parm_type_p (t, complain))
5651 return error_mark_node;
5653 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5655 if (same_type_p (t, TREE_TYPE (orig_arg)))
5659 /* Not sure if this is reachable, but it doesn't hurt
5661 error ("type mismatch in nontype parameter pack");
5662 val = error_mark_node;
5665 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5666 /* We used to call digest_init here. However, digest_init
5667 will report errors, which we don't want when complain
5668 is zero. More importantly, digest_init will try too
5669 hard to convert things: for example, `0' should not be
5670 converted to pointer type at this point according to
5671 the standard. Accepting this is not merely an
5672 extension, since deciding whether or not these
5673 conversions can occur is part of determining which
5674 function template to call, or whether a given explicit
5675 argument specification is valid. */
5676 val = convert_nontype_argument (t, orig_arg);
5680 if (val == NULL_TREE)
5681 val = error_mark_node;
5682 else if (val == error_mark_node && (complain & tf_error))
5683 error ("could not convert template argument %qE to %qT", orig_arg, t);
5685 if (TREE_CODE (val) == SCOPE_REF)
5687 /* Strip typedefs from the SCOPE_REF. */
5688 tree type = strip_typedefs (TREE_TYPE (val));
5689 tree scope = strip_typedefs (TREE_OPERAND (val, 0));
5690 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
5691 QUALIFIED_NAME_IS_TEMPLATE (val));
5698 /* Coerces the remaining template arguments in INNER_ARGS (from
5699 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5700 Returns the coerced argument pack. PARM_IDX is the position of this
5701 parameter in the template parameter list. ARGS is the original
5702 template argument list. */
5704 coerce_template_parameter_pack (tree parms,
5712 tsubst_flags_t complain)
5714 tree parm = TREE_VEC_ELT (parms, parm_idx);
5715 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5718 tree packed_types = NULL_TREE;
5720 if (arg_idx > nargs)
5723 packed_args = make_tree_vec (nargs - arg_idx);
5725 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5726 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5728 /* When the template parameter is a non-type template
5729 parameter pack whose type uses parameter packs, we need
5730 to look at each of the template arguments
5731 separately. Build a vector of the types for these
5732 non-type template parameters in PACKED_TYPES. */
5734 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5735 packed_types = tsubst_pack_expansion (expansion, args,
5738 if (packed_types == error_mark_node)
5739 return error_mark_node;
5741 /* Check that we have the right number of arguments. */
5743 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5744 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5747 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5748 error ("wrong number of template arguments (%d, should be %d)",
5749 nargs, needed_parms);
5750 return error_mark_node;
5753 /* If we aren't able to check the actual arguments now
5754 (because they haven't been expanded yet), we can at least
5755 verify that all of the types used for the non-type
5756 template parameter pack are, in fact, valid for non-type
5757 template parameters. */
5759 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5761 int j, len = TREE_VEC_LENGTH (packed_types);
5762 for (j = 0; j < len; ++j)
5764 tree t = TREE_VEC_ELT (packed_types, j);
5765 if (invalid_nontype_parm_type_p (t, complain))
5766 return error_mark_node;
5771 /* Convert the remaining arguments, which will be a part of the
5772 parameter pack "parm". */
5773 for (; arg_idx < nargs; ++arg_idx)
5775 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5776 tree actual_parm = TREE_VALUE (parm);
5778 if (packed_types && !PACK_EXPANSION_P (arg))
5780 /* When we have a vector of types (corresponding to the
5781 non-type template parameter pack that uses parameter
5782 packs in its type, as mention above), and the
5783 argument is not an expansion (which expands to a
5784 currently unknown number of arguments), clone the
5785 parm and give it the next type in PACKED_TYPES. */
5786 actual_parm = copy_node (actual_parm);
5787 TREE_TYPE (actual_parm) =
5788 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5791 if (arg != error_mark_node)
5792 arg = convert_template_argument (actual_parm,
5793 arg, new_args, complain, parm_idx,
5795 if (arg == error_mark_node)
5797 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5800 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5801 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5802 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
5805 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5806 TREE_TYPE (argument_pack)
5807 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5808 TREE_CONSTANT (argument_pack) = 1;
5811 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5812 #ifdef ENABLE_CHECKING
5813 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
5814 TREE_VEC_LENGTH (packed_args));
5816 return argument_pack;
5819 /* Convert all template arguments to their appropriate types, and
5820 return a vector containing the innermost resulting template
5821 arguments. If any error occurs, return error_mark_node. Error and
5822 warning messages are issued under control of COMPLAIN.
5824 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5825 for arguments not specified in ARGS. Otherwise, if
5826 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5827 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5828 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5832 coerce_template_parms (tree parms,
5835 tsubst_flags_t complain,
5836 bool require_all_args,
5837 bool use_default_args)
5839 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5842 tree new_inner_args;
5843 int saved_unevaluated_operand;
5844 int saved_inhibit_evaluation_warnings;
5846 /* When used as a boolean value, indicates whether this is a
5847 variadic template parameter list. Since it's an int, we can also
5848 subtract it from nparms to get the number of non-variadic
5852 nparms = TREE_VEC_LENGTH (parms);
5854 /* Determine if there are any parameter packs. */
5855 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5857 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5858 if (template_parameter_pack_p (tparm))
5862 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5863 /* If there are 0 or 1 parameter packs, we need to expand any argument
5864 packs so that we can deduce a parameter pack from some non-packed args
5865 followed by an argument pack, as in variadic85.C. If there are more
5866 than that, we need to leave argument packs intact so the arguments are
5867 assigned to the right parameter packs. This should only happen when
5868 dealing with a nested class inside a partial specialization of a class
5869 template, as in variadic92.C. */
5870 if (variadic_p <= 1)
5871 inner_args = expand_template_argument_pack (inner_args);
5873 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5874 if ((nargs > nparms && !variadic_p)
5875 || (nargs < nparms - variadic_p
5877 && (!use_default_args
5878 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5879 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5881 if (complain & tf_error)
5883 const char *or_more = "";
5886 or_more = " or more";
5890 error ("wrong number of template arguments (%d, should be %d%s)",
5891 nargs, nparms, or_more);
5894 error ("provided for %q+D", in_decl);
5897 return error_mark_node;
5900 /* We need to evaluate the template arguments, even though this
5901 template-id may be nested within a "sizeof". */
5902 saved_unevaluated_operand = cp_unevaluated_operand;
5903 cp_unevaluated_operand = 0;
5904 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5905 c_inhibit_evaluation_warnings = 0;
5906 new_inner_args = make_tree_vec (nparms);
5907 new_args = add_outermost_template_args (args, new_inner_args);
5908 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5913 /* Get the Ith template parameter. */
5914 parm = TREE_VEC_ELT (parms, parm_idx);
5916 if (parm == error_mark_node)
5918 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5922 /* Calculate the next argument. */
5923 if (arg_idx < nargs)
5924 arg = TREE_VEC_ELT (inner_args, arg_idx);
5928 if (template_parameter_pack_p (TREE_VALUE (parm))
5929 && !(arg && ARGUMENT_PACK_P (arg)))
5931 /* All remaining arguments will be placed in the
5932 template parameter pack PARM. */
5933 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5934 inner_args, arg_idx,
5938 /* Store this argument. */
5939 if (arg == error_mark_node)
5941 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5943 /* We are done with all of the arguments. */
5950 if (PACK_EXPANSION_P (arg))
5952 if (complain & tf_error)
5954 /* FIXME this restriction was removed by N2555; see
5956 /* If ARG is a pack expansion, but PARM is not a
5957 template parameter pack (if it were, we would have
5958 handled it above), we're trying to expand into a
5959 fixed-length argument list. */
5960 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5961 sorry ("cannot expand %<%E%> into a fixed-length "
5962 "argument list", arg);
5964 sorry ("cannot expand %<%T%> into a fixed-length "
5965 "argument list", arg);
5967 return error_mark_node;
5970 else if (require_all_args)
5972 /* There must be a default arg in this case. */
5973 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5975 /* The position of the first default template argument,
5976 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
5978 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
5979 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
5984 if (arg == error_mark_node)
5986 if (complain & tf_error)
5987 error ("template argument %d is invalid", arg_idx + 1);
5990 /* This only occurs if there was an error in the template
5991 parameter list itself (which we would already have
5992 reported) that we are trying to recover from, e.g., a class
5993 template with a parameter list such as
5994 template<typename..., typename>. */
5995 return error_mark_node;
5997 arg = convert_template_argument (TREE_VALUE (parm),
5998 arg, new_args, complain,
6001 if (arg == error_mark_node)
6003 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6005 cp_unevaluated_operand = saved_unevaluated_operand;
6006 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6009 return error_mark_node;
6011 #ifdef ENABLE_CHECKING
6012 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6013 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6014 TREE_VEC_LENGTH (new_inner_args));
6017 return new_inner_args;
6020 /* Returns 1 if template args OT and NT are equivalent. */
6023 template_args_equal (tree ot, tree nt)
6028 if (TREE_CODE (nt) == TREE_VEC)
6029 /* For member templates */
6030 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6031 else if (PACK_EXPANSION_P (ot))
6032 return PACK_EXPANSION_P (nt)
6033 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6034 PACK_EXPANSION_PATTERN (nt));
6035 else if (ARGUMENT_PACK_P (ot))
6040 if (!ARGUMENT_PACK_P (nt))
6043 opack = ARGUMENT_PACK_ARGS (ot);
6044 npack = ARGUMENT_PACK_ARGS (nt);
6045 len = TREE_VEC_LENGTH (opack);
6046 if (TREE_VEC_LENGTH (npack) != len)
6048 for (i = 0; i < len; ++i)
6049 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6050 TREE_VEC_ELT (npack, i)))
6054 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6056 /* We get here probably because we are in the middle of substituting
6057 into the pattern of a pack expansion. In that case the
6058 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6059 interested in. So we want to use the initial pack argument for
6061 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6062 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6063 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6064 return template_args_equal (ot, nt);
6066 else if (TYPE_P (nt))
6067 return TYPE_P (ot) && same_type_p (ot, nt);
6068 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6071 return cp_tree_equal (ot, nt);
6074 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6075 of template arguments. Returns 0 otherwise. */
6078 comp_template_args (tree oldargs, tree newargs)
6082 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6085 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6087 tree nt = TREE_VEC_ELT (newargs, i);
6088 tree ot = TREE_VEC_ELT (oldargs, i);
6090 if (! template_args_equal (ot, nt))
6097 add_pending_template (tree d)
6099 tree ti = (TYPE_P (d)
6100 ? CLASSTYPE_TEMPLATE_INFO (d)
6101 : DECL_TEMPLATE_INFO (d));
6102 struct pending_template *pt;
6105 if (TI_PENDING_TEMPLATE_FLAG (ti))
6108 /* We are called both from instantiate_decl, where we've already had a
6109 tinst_level pushed, and instantiate_template, where we haven't.
6111 level = !current_tinst_level || current_tinst_level->decl != d;
6114 push_tinst_level (d);
6116 pt = GGC_NEW (struct pending_template);
6118 pt->tinst = current_tinst_level;
6119 if (last_pending_template)
6120 last_pending_template->next = pt;
6122 pending_templates = pt;
6124 last_pending_template = pt;
6126 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6133 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6134 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6135 documentation for TEMPLATE_ID_EXPR. */
6138 lookup_template_function (tree fns, tree arglist)
6142 if (fns == error_mark_node || arglist == error_mark_node)
6143 return error_mark_node;
6145 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6146 gcc_assert (fns && (is_overloaded_fn (fns)
6147 || TREE_CODE (fns) == IDENTIFIER_NODE));
6149 if (BASELINK_P (fns))
6151 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6153 BASELINK_FUNCTIONS (fns),
6158 type = TREE_TYPE (fns);
6159 if (TREE_CODE (fns) == OVERLOAD || !type)
6160 type = unknown_type_node;
6162 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6165 /* Within the scope of a template class S<T>, the name S gets bound
6166 (in build_self_reference) to a TYPE_DECL for the class, not a
6167 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6168 or one of its enclosing classes, and that type is a template,
6169 return the associated TEMPLATE_DECL. Otherwise, the original
6172 Also handle the case when DECL is a TREE_LIST of ambiguous
6173 injected-class-names from different bases. */
6176 maybe_get_template_decl_from_type_decl (tree decl)
6178 if (decl == NULL_TREE)
6181 /* DR 176: A lookup that finds an injected-class-name (10.2
6182 [class.member.lookup]) can result in an ambiguity in certain cases
6183 (for example, if it is found in more than one base class). If all of
6184 the injected-class-names that are found refer to specializations of
6185 the same class template, and if the name is followed by a
6186 template-argument-list, the reference refers to the class template
6187 itself and not a specialization thereof, and is not ambiguous. */
6188 if (TREE_CODE (decl) == TREE_LIST)
6190 tree t, tmpl = NULL_TREE;
6191 for (t = decl; t; t = TREE_CHAIN (t))
6193 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
6196 else if (tmpl != elt)
6199 if (tmpl && t == NULL_TREE)
6205 return (decl != NULL_TREE
6206 && DECL_SELF_REFERENCE_P (decl)
6207 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
6208 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
6211 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
6212 parameters, find the desired type.
6214 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
6216 IN_DECL, if non-NULL, is the template declaration we are trying to
6219 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
6220 the class we are looking up.
6222 Issue error and warning messages under control of COMPLAIN.
6224 If the template class is really a local class in a template
6225 function, then the FUNCTION_CONTEXT is the function in which it is
6228 ??? Note that this function is currently called *twice* for each
6229 template-id: the first time from the parser, while creating the
6230 incomplete type (finish_template_type), and the second type during the
6231 real instantiation (instantiate_template_class). This is surely something
6232 that we want to avoid. It also causes some problems with argument
6233 coercion (see convert_nontype_argument for more information on this). */
6236 lookup_template_class (tree d1,
6241 tsubst_flags_t complain)
6243 tree templ = NULL_TREE, parmlist;
6250 timevar_push (TV_NAME_LOOKUP);
6252 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6254 tree value = innermost_non_namespace_value (d1);
6255 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6260 push_decl_namespace (context);
6261 templ = lookup_name (d1);
6262 templ = maybe_get_template_decl_from_type_decl (templ);
6264 pop_decl_namespace ();
6267 context = DECL_CONTEXT (templ);
6269 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6271 tree type = TREE_TYPE (d1);
6273 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6274 an implicit typename for the second A. Deal with it. */
6275 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6276 type = TREE_TYPE (type);
6278 if (CLASSTYPE_TEMPLATE_INFO (type))
6280 templ = CLASSTYPE_TI_TEMPLATE (type);
6281 d1 = DECL_NAME (templ);
6284 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6285 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6287 templ = TYPE_TI_TEMPLATE (d1);
6288 d1 = DECL_NAME (templ);
6290 else if (TREE_CODE (d1) == TEMPLATE_DECL
6291 && DECL_TEMPLATE_RESULT (d1)
6292 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6295 d1 = DECL_NAME (templ);
6296 context = DECL_CONTEXT (templ);
6299 /* Issue an error message if we didn't find a template. */
6302 if (complain & tf_error)
6303 error ("%qT is not a template", d1);
6304 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6307 if (TREE_CODE (templ) != TEMPLATE_DECL
6308 /* Make sure it's a user visible template, if it was named by
6310 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6311 && !PRIMARY_TEMPLATE_P (templ)))
6313 if (complain & tf_error)
6315 error ("non-template type %qT used as a template", d1);
6317 error ("for template declaration %q+D", in_decl);
6319 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6322 complain &= ~tf_user;
6324 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6326 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6327 template arguments */
6333 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6335 /* Consider an example where a template template parameter declared as
6337 template <class T, class U = std::allocator<T> > class TT
6339 The template parameter level of T and U are one level larger than
6340 of TT. To proper process the default argument of U, say when an
6341 instantiation `TT<int>' is seen, we need to build the full
6342 arguments containing {int} as the innermost level. Outer levels,
6343 available when not appearing as default template argument, can be
6344 obtained from the arguments of the enclosing template.
6346 Suppose that TT is later substituted with std::vector. The above
6347 instantiation is `TT<int, std::allocator<T> >' with TT at
6348 level 1, and T at level 2, while the template arguments at level 1
6349 becomes {std::vector} and the inner level 2 is {int}. */
6351 outer = DECL_CONTEXT (templ);
6353 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6354 else if (current_template_parms)
6355 /* This is an argument of the current template, so we haven't set
6356 DECL_CONTEXT yet. */
6357 outer = current_template_args ();
6360 arglist = add_to_template_args (outer, arglist);
6362 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6364 /*require_all_args=*/true,
6365 /*use_default_args=*/true);
6366 if (arglist2 == error_mark_node
6367 || (!uses_template_parms (arglist2)
6368 && check_instantiated_args (templ, arglist2, complain)))
6369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6371 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6372 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6376 tree template_type = TREE_TYPE (templ);
6379 tree found = NULL_TREE;
6382 int is_dependent_type;
6383 int use_partial_inst_tmpl = false;
6385 gen_tmpl = most_general_template (templ);
6386 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6387 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6388 arg_depth = TMPL_ARGS_DEPTH (arglist);
6390 if (arg_depth == 1 && parm_depth > 1)
6392 /* We've been given an incomplete set of template arguments.
6395 template <class T> struct S1 {
6396 template <class U> struct S2 {};
6397 template <class U> struct S2<U*> {};
6400 we will be called with an ARGLIST of `U*', but the
6401 TEMPLATE will be `template <class T> template
6402 <class U> struct S1<T>::S2'. We must fill in the missing
6405 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6407 arg_depth = TMPL_ARGS_DEPTH (arglist);
6410 /* Now we should have enough arguments. */
6411 gcc_assert (parm_depth == arg_depth);
6413 /* From here on, we're only interested in the most general
6416 /* Calculate the BOUND_ARGS. These will be the args that are
6417 actually tsubst'd into the definition to create the
6421 /* We have multiple levels of arguments to coerce, at once. */
6423 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6425 tree bound_args = make_tree_vec (parm_depth);
6427 for (i = saved_depth,
6428 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6429 i > 0 && t != NULL_TREE;
6430 --i, t = TREE_CHAIN (t))
6432 tree a = coerce_template_parms (TREE_VALUE (t),
6435 /*require_all_args=*/true,
6436 /*use_default_args=*/true);
6438 /* Don't process further if one of the levels fails. */
6439 if (a == error_mark_node)
6441 /* Restore the ARGLIST to its full size. */
6442 TREE_VEC_LENGTH (arglist) = saved_depth;
6443 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6446 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6448 /* We temporarily reduce the length of the ARGLIST so
6449 that coerce_template_parms will see only the arguments
6450 corresponding to the template parameters it is
6452 TREE_VEC_LENGTH (arglist)--;
6455 /* Restore the ARGLIST to its full size. */
6456 TREE_VEC_LENGTH (arglist) = saved_depth;
6458 arglist = bound_args;
6462 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6463 INNERMOST_TEMPLATE_ARGS (arglist),
6466 /*require_all_args=*/true,
6467 /*use_default_args=*/true);
6469 if (arglist == error_mark_node)
6470 /* We were unable to bind the arguments. */
6471 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6473 /* In the scope of a template class, explicit references to the
6474 template class refer to the type of the template, not any
6475 instantiation of it. For example, in:
6477 template <class T> class C { void f(C<T>); }
6479 the `C<T>' is just the same as `C'. Outside of the
6480 class, however, such a reference is an instantiation. */
6482 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6483 || currently_open_class (template_type))
6484 /* comp_template_args is expensive, check it last. */
6485 && comp_template_args (TYPE_TI_ARGS (template_type),
6487 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6489 /* If we already have this specialization, return it. */
6490 elt.tmpl = gen_tmpl;
6492 hash = hash_specialization (&elt);
6493 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6497 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6499 is_dependent_type = uses_template_parms (arglist);
6501 /* If the deduced arguments are invalid, then the binding
6503 if (!is_dependent_type
6504 && check_instantiated_args (gen_tmpl,
6505 INNERMOST_TEMPLATE_ARGS (arglist),
6507 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6509 if (!is_dependent_type
6510 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6511 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6512 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6514 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6515 DECL_NAME (gen_tmpl),
6516 /*tag_scope=*/ts_global);
6517 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6520 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6523 context = global_namespace;
6525 /* Create the type. */
6526 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6528 if (!is_dependent_type)
6530 set_current_access_from_decl (TYPE_NAME (template_type));
6531 t = start_enum (TYPE_IDENTIFIER (template_type),
6532 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6533 arglist, complain, in_decl),
6534 SCOPED_ENUM_P (template_type));
6538 /* We don't want to call start_enum for this type, since
6539 the values for the enumeration constants may involve
6540 template parameters. And, no one should be interested
6541 in the enumeration constants for such a type. */
6542 t = cxx_make_type (ENUMERAL_TYPE);
6543 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6548 t = make_class_type (TREE_CODE (template_type));
6549 CLASSTYPE_DECLARED_CLASS (t)
6550 = CLASSTYPE_DECLARED_CLASS (template_type);
6551 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6552 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6554 /* A local class. Make sure the decl gets registered properly. */
6555 if (context == current_function_decl)
6556 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6558 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6559 /* This instantiation is another name for the primary
6560 template type. Set the TYPE_CANONICAL field
6562 TYPE_CANONICAL (t) = template_type;
6563 else if (any_template_arguments_need_structural_equality_p (arglist))
6564 /* Some of the template arguments require structural
6565 equality testing, so this template class requires
6566 structural equality testing. */
6567 SET_TYPE_STRUCTURAL_EQUALITY (t);
6570 /* If we called start_enum or pushtag above, this information
6571 will already be set up. */
6574 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6576 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6577 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6578 DECL_SOURCE_LOCATION (type_decl)
6579 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6582 type_decl = TYPE_NAME (t);
6584 TREE_PRIVATE (type_decl)
6585 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6586 TREE_PROTECTED (type_decl)
6587 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6588 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6590 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6591 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6594 /* Let's consider the explicit specialization of a member
6595 of a class template specialization that is implicitely instantiated,
6600 template<class U> struct M {}; //#0
6605 struct S<int>::M<char> //#1
6609 [temp.expl.spec]/4 says this is valid.
6611 In this case, when we write:
6614 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
6617 When we encounter #1, we want to store the partial instantiation
6618 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
6620 For all cases other than this "explicit specialization of member of a
6621 class template", we just want to store the most general template into
6622 the CLASSTYPE_TI_TEMPLATE of M.
6624 This case of "explicit specialization of member of a class template"
6626 1/ the enclosing class is an instantiation of, and therefore not
6627 the same as, the context of the most general template, and
6628 2/ we aren't looking at the partial instantiation itself, i.e.
6629 the innermost arguments are not the same as the innermost parms of
6630 the most general template.
6632 So it's only when 1/ and 2/ happens that we want to use the partial
6633 instantiation of the member template in lieu of its most general
6636 if (PRIMARY_TEMPLATE_P (gen_tmpl)
6637 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
6638 /* the enclosing class must be an instantiation... */
6639 && CLASS_TYPE_P (context)
6640 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
6642 tree partial_inst_args;
6643 TREE_VEC_LENGTH (arglist)--;
6644 ++processing_template_decl;
6646 tsubst (INNERMOST_TEMPLATE_ARGS
6647 (CLASSTYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
6648 arglist, complain, NULL_TREE);
6649 --processing_template_decl;
6650 TREE_VEC_LENGTH (arglist)++;
6651 use_partial_inst_tmpl =
6652 /*...and we must not be looking at the partial instantiation
6654 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
6658 if (!use_partial_inst_tmpl)
6659 /* This case is easy; there are no member templates involved. */
6663 /* This is a full instantiation of a member template. Find
6664 the partial instantiation of which this is an instance. */
6666 /* Temporarily reduce by one the number of levels in the ARGLIST
6667 so as to avoid comparing the last set of arguments. */
6668 TREE_VEC_LENGTH (arglist)--;
6669 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6670 TREE_VEC_LENGTH (arglist)++;
6671 found = CLASSTYPE_TI_TEMPLATE (found);
6674 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
6677 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6678 &elt, hash, INSERT);
6679 *slot = GGC_NEW (spec_entry);
6682 /* Note this use of the partial instantiation so we can check it
6683 later in maybe_process_partial_specialization. */
6684 DECL_TEMPLATE_INSTANTIATIONS (templ)
6685 = tree_cons (arglist, t,
6686 DECL_TEMPLATE_INSTANTIATIONS (templ));
6688 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
6689 /* Now that the type has been registered on the instantiations
6690 list, we set up the enumerators. Because the enumeration
6691 constants may involve the enumeration type itself, we make
6692 sure to register the type first, and then create the
6693 constants. That way, doing tsubst_expr for the enumeration
6694 constants won't result in recursive calls here; we'll find
6695 the instantiation and exit above. */
6696 tsubst_enum (template_type, t, arglist);
6698 if (is_dependent_type)
6699 /* If the type makes use of template parameters, the
6700 code that generates debugging information will crash. */
6701 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6703 /* Possibly limit visibility based on template args. */
6704 TREE_PUBLIC (type_decl) = 1;
6705 determine_visibility (type_decl);
6707 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6709 timevar_pop (TV_NAME_LOOKUP);
6716 /* True when we should also visit template parameters that occur in
6717 non-deduced contexts. */
6718 bool include_nondeduced_p;
6719 struct pointer_set_t *visited;
6722 /* Called from for_each_template_parm via walk_tree. */
6725 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6728 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6729 tree_fn_t fn = pfd->fn;
6730 void *data = pfd->data;
6733 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6734 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6735 pfd->include_nondeduced_p))
6736 return error_mark_node;
6738 switch (TREE_CODE (t))
6741 if (TYPE_PTRMEMFUNC_P (t))
6747 if (!TYPE_TEMPLATE_INFO (t))
6749 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
6750 fn, data, pfd->visited,
6751 pfd->include_nondeduced_p))
6752 return error_mark_node;
6756 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6757 fn, data, pfd->visited,
6758 pfd->include_nondeduced_p)
6759 || for_each_template_parm (TYPE_MAX_VALUE (t),
6760 fn, data, pfd->visited,
6761 pfd->include_nondeduced_p))
6762 return error_mark_node;
6766 /* Since we're not going to walk subtrees, we have to do this
6768 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6769 pfd->visited, pfd->include_nondeduced_p))
6770 return error_mark_node;
6774 /* Check the return type. */
6775 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6776 pfd->include_nondeduced_p))
6777 return error_mark_node;
6779 /* Check the parameter types. Since default arguments are not
6780 instantiated until they are needed, the TYPE_ARG_TYPES may
6781 contain expressions that involve template parameters. But,
6782 no-one should be looking at them yet. And, once they're
6783 instantiated, they don't contain template parameters, so
6784 there's no point in looking at them then, either. */
6788 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6789 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6790 pfd->visited, pfd->include_nondeduced_p))
6791 return error_mark_node;
6793 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6794 want walk_tree walking into them itself. */
6800 if (pfd->include_nondeduced_p
6801 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6803 pfd->include_nondeduced_p))
6804 return error_mark_node;
6809 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6810 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6811 pfd->visited, pfd->include_nondeduced_p))
6812 return error_mark_node;
6817 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6818 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6819 pfd->visited, pfd->include_nondeduced_p))
6820 return error_mark_node;
6821 if (DECL_CONTEXT (t)
6822 && pfd->include_nondeduced_p
6823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6824 pfd->visited, pfd->include_nondeduced_p))
6825 return error_mark_node;
6828 case BOUND_TEMPLATE_TEMPLATE_PARM:
6829 /* Record template parameters such as `T' inside `TT<T>'. */
6830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6831 pfd->include_nondeduced_p))
6832 return error_mark_node;
6835 case TEMPLATE_TEMPLATE_PARM:
6836 case TEMPLATE_TYPE_PARM:
6837 case TEMPLATE_PARM_INDEX:
6838 if (fn && (*fn)(t, data))
6839 return error_mark_node;
6841 return error_mark_node;
6845 /* A template template parameter is encountered. */
6846 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6847 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6848 pfd->include_nondeduced_p))
6849 return error_mark_node;
6851 /* Already substituted template template parameter */
6857 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6859 pfd->include_nondeduced_p))
6860 return error_mark_node;
6864 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6865 && pfd->include_nondeduced_p
6866 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6867 (TREE_TYPE (t)), fn, data,
6868 pfd->visited, pfd->include_nondeduced_p))
6869 return error_mark_node;
6874 /* If there's no type, then this thing must be some expression
6875 involving template parameters. */
6876 if (!fn && !TREE_TYPE (t))
6877 return error_mark_node;
6882 case REINTERPRET_CAST_EXPR:
6883 case CONST_CAST_EXPR:
6884 case STATIC_CAST_EXPR:
6885 case DYNAMIC_CAST_EXPR:
6889 case PSEUDO_DTOR_EXPR:
6891 return error_mark_node;
6898 /* We didn't find any template parameters we liked. */
6902 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6903 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6904 call FN with the parameter and the DATA.
6905 If FN returns nonzero, the iteration is terminated, and
6906 for_each_template_parm returns 1. Otherwise, the iteration
6907 continues. If FN never returns a nonzero value, the value
6908 returned by for_each_template_parm is 0. If FN is NULL, it is
6909 considered to be the function which always returns 1.
6911 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6912 parameters that occur in non-deduced contexts. When false, only
6913 visits those template parameters that can be deduced. */
6916 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6917 struct pointer_set_t *visited,
6918 bool include_nondeduced_p)
6920 struct pair_fn_data pfd;
6926 pfd.include_nondeduced_p = include_nondeduced_p;
6928 /* Walk the tree. (Conceptually, we would like to walk without
6929 duplicates, but for_each_template_parm_r recursively calls
6930 for_each_template_parm, so we would need to reorganize a fair
6931 bit to use walk_tree_without_duplicates, so we keep our own
6934 pfd.visited = visited;
6936 pfd.visited = pointer_set_create ();
6937 result = cp_walk_tree (&t,
6938 for_each_template_parm_r,
6940 pfd.visited) != NULL_TREE;
6945 pointer_set_destroy (pfd.visited);
6952 /* Returns true if T depends on any template parameter. */
6955 uses_template_parms (tree t)
6958 int saved_processing_template_decl;
6960 saved_processing_template_decl = processing_template_decl;
6961 if (!saved_processing_template_decl)
6962 processing_template_decl = 1;
6964 dependent_p = dependent_type_p (t);
6965 else if (TREE_CODE (t) == TREE_VEC)
6966 dependent_p = any_dependent_template_arguments_p (t);
6967 else if (TREE_CODE (t) == TREE_LIST)
6968 dependent_p = (uses_template_parms (TREE_VALUE (t))
6969 || uses_template_parms (TREE_CHAIN (t)));
6970 else if (TREE_CODE (t) == TYPE_DECL)
6971 dependent_p = dependent_type_p (TREE_TYPE (t));
6974 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6975 || TREE_CODE (t) == OVERLOAD
6976 || TREE_CODE (t) == BASELINK
6977 || TREE_CODE (t) == IDENTIFIER_NODE
6978 || TREE_CODE (t) == TRAIT_EXPR
6979 || TREE_CODE (t) == CONSTRUCTOR
6980 || CONSTANT_CLASS_P (t))
6981 dependent_p = (type_dependent_expression_p (t)
6982 || value_dependent_expression_p (t));
6985 gcc_assert (t == error_mark_node);
6986 dependent_p = false;
6989 processing_template_decl = saved_processing_template_decl;
6994 /* Returns true if T depends on any template parameter with level LEVEL. */
6997 uses_template_parms_level (tree t, int level)
6999 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7000 /*include_nondeduced_p=*/true);
7003 static int tinst_depth;
7004 extern int max_tinst_depth;
7005 #ifdef GATHER_STATISTICS
7008 static int tinst_level_tick;
7009 static int last_template_error_tick;
7011 /* We're starting to instantiate D; record the template instantiation context
7012 for diagnostics and to restore it later. */
7015 push_tinst_level (tree d)
7017 struct tinst_level *new_level;
7019 if (tinst_depth >= max_tinst_depth)
7021 /* If the instantiation in question still has unbound template parms,
7022 we don't really care if we can't instantiate it, so just return.
7023 This happens with base instantiation for implicit `typename'. */
7024 if (uses_template_parms (d))
7027 last_template_error_tick = tinst_level_tick;
7028 error ("template instantiation depth exceeds maximum of %d (use "
7029 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7030 max_tinst_depth, d);
7032 print_instantiation_context ();
7037 new_level = GGC_NEW (struct tinst_level);
7038 new_level->decl = d;
7039 new_level->locus = input_location;
7040 new_level->in_system_header_p = in_system_header;
7041 new_level->next = current_tinst_level;
7042 current_tinst_level = new_level;
7045 #ifdef GATHER_STATISTICS
7046 if (tinst_depth > depth_reached)
7047 depth_reached = tinst_depth;
7054 /* We're done instantiating this template; return to the instantiation
7058 pop_tinst_level (void)
7060 /* Restore the filename and line number stashed away when we started
7061 this instantiation. */
7062 input_location = current_tinst_level->locus;
7063 current_tinst_level = current_tinst_level->next;
7068 /* We're instantiating a deferred template; restore the template
7069 instantiation context in which the instantiation was requested, which
7070 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7073 reopen_tinst_level (struct tinst_level *level)
7075 struct tinst_level *t;
7078 for (t = level; t; t = t->next)
7081 current_tinst_level = level;
7086 /* Returns the TINST_LEVEL which gives the original instantiation
7089 struct tinst_level *
7090 outermost_tinst_level (void)
7092 struct tinst_level *level = current_tinst_level;
7095 level = level->next;
7099 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7102 parameter_of_template_p (tree parm, tree templ)
7107 if (!parm || !templ)
7110 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7111 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7113 parms = DECL_TEMPLATE_PARMS (templ);
7114 parms = INNERMOST_TEMPLATE_PARMS (parms);
7116 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7117 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7123 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7124 vector of template arguments, as for tsubst.
7126 Returns an appropriate tsubst'd friend declaration. */
7129 tsubst_friend_function (tree decl, tree args)
7133 if (TREE_CODE (decl) == FUNCTION_DECL
7134 && DECL_TEMPLATE_INSTANTIATION (decl)
7135 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7136 /* This was a friend declared with an explicit template
7137 argument list, e.g.:
7141 to indicate that f was a template instantiation, not a new
7142 function declaration. Now, we have to figure out what
7143 instantiation of what template. */
7145 tree template_id, arglist, fns;
7148 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7150 /* Friend functions are looked up in the containing namespace scope.
7151 We must enter that scope, to avoid finding member functions of the
7152 current class with same name. */
7153 push_nested_namespace (ns);
7154 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7155 tf_warning_or_error, NULL_TREE,
7156 /*integral_constant_expression_p=*/false);
7157 pop_nested_namespace (ns);
7158 arglist = tsubst (DECL_TI_ARGS (decl), args,
7159 tf_warning_or_error, NULL_TREE);
7160 template_id = lookup_template_function (fns, arglist);
7162 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7163 tmpl = determine_specialization (template_id, new_friend,
7165 /*need_member_template=*/0,
7166 TREE_VEC_LENGTH (args),
7168 return instantiate_template (tmpl, new_args, tf_error);
7171 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7173 /* The NEW_FRIEND will look like an instantiation, to the
7174 compiler, but is not an instantiation from the point of view of
7175 the language. For example, we might have had:
7177 template <class T> struct S {
7178 template <class U> friend void f(T, U);
7181 Then, in S<int>, template <class U> void f(int, U) is not an
7182 instantiation of anything. */
7183 if (new_friend == error_mark_node)
7184 return error_mark_node;
7186 DECL_USE_TEMPLATE (new_friend) = 0;
7187 if (TREE_CODE (decl) == TEMPLATE_DECL)
7189 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7190 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7191 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7194 /* The mangled name for the NEW_FRIEND is incorrect. The function
7195 is not a template instantiation and should not be mangled like
7196 one. Therefore, we forget the mangling here; we'll recompute it
7197 later if we need it. */
7198 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7200 SET_DECL_RTL (new_friend, NULL_RTX);
7201 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7204 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7207 tree new_friend_template_info;
7208 tree new_friend_result_template_info;
7210 int new_friend_is_defn;
7212 /* We must save some information from NEW_FRIEND before calling
7213 duplicate decls since that function will free NEW_FRIEND if
7215 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7216 new_friend_is_defn =
7217 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7218 (template_for_substitution (new_friend)))
7220 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7222 /* This declaration is a `primary' template. */
7223 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7225 new_friend_result_template_info
7226 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7229 new_friend_result_template_info = NULL_TREE;
7231 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7232 if (new_friend_is_defn)
7233 DECL_INITIAL (new_friend) = error_mark_node;
7235 /* Inside pushdecl_namespace_level, we will push into the
7236 current namespace. However, the friend function should go
7237 into the namespace of the template. */
7238 ns = decl_namespace_context (new_friend);
7239 push_nested_namespace (ns);
7240 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7241 pop_nested_namespace (ns);
7243 if (old_decl == error_mark_node)
7244 return error_mark_node;
7246 if (old_decl != new_friend)
7248 /* This new friend declaration matched an existing
7249 declaration. For example, given:
7251 template <class T> void f(T);
7252 template <class U> class C {
7253 template <class T> friend void f(T) {}
7256 the friend declaration actually provides the definition
7257 of `f', once C has been instantiated for some type. So,
7258 old_decl will be the out-of-class template declaration,
7259 while new_friend is the in-class definition.
7261 But, if `f' was called before this point, the
7262 instantiation of `f' will have DECL_TI_ARGS corresponding
7263 to `T' but not to `U', references to which might appear
7264 in the definition of `f'. Previously, the most general
7265 template for an instantiation of `f' was the out-of-class
7266 version; now it is the in-class version. Therefore, we
7267 run through all specialization of `f', adding to their
7268 DECL_TI_ARGS appropriately. In particular, they need a
7269 new set of outer arguments, corresponding to the
7270 arguments for this class instantiation.
7272 The same situation can arise with something like this:
7275 template <class T> class C {
7279 when `C<int>' is instantiated. Now, `f(int)' is defined
7282 if (!new_friend_is_defn)
7283 /* On the other hand, if the in-class declaration does
7284 *not* provide a definition, then we don't want to alter
7285 existing definitions. We can just leave everything
7290 tree new_template = TI_TEMPLATE (new_friend_template_info);
7291 tree new_args = TI_ARGS (new_friend_template_info);
7293 /* Overwrite whatever template info was there before, if
7294 any, with the new template information pertaining to
7296 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7298 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7299 /* We should have called reregister_specialization in
7301 gcc_assert (retrieve_specialization (new_template,
7308 /* Indicate that the old function template is a partial
7310 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7311 = new_friend_result_template_info;
7313 gcc_assert (new_template
7314 == most_general_template (new_template));
7315 gcc_assert (new_template != old_decl);
7317 /* Reassign any specializations already in the hash table
7318 to the new more general template, and add the
7319 additional template args. */
7320 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7324 tree spec = TREE_VALUE (t);
7327 elt.tmpl = old_decl;
7328 elt.args = DECL_TI_ARGS (spec);
7329 elt.spec = NULL_TREE;
7331 htab_remove_elt (decl_specializations, &elt);
7334 = add_outermost_template_args (new_args,
7335 DECL_TI_ARGS (spec));
7337 register_specialization
7338 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7341 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7345 /* The information from NEW_FRIEND has been merged into OLD_DECL
7346 by duplicate_decls. */
7347 new_friend = old_decl;
7352 tree context = DECL_CONTEXT (new_friend);
7356 template <class T> class C {
7357 template <class U> friend void C1<U>::f (); // case 1
7358 friend void C2<T>::f (); // case 2
7360 we only need to make sure CONTEXT is a complete type for
7361 case 2. To distinguish between the two cases, we note that
7362 CONTEXT of case 1 remains dependent type after tsubst while
7363 this isn't true for case 2. */
7364 ++processing_template_decl;
7365 dependent_p = dependent_type_p (context);
7366 --processing_template_decl;
7369 && !complete_type_or_else (context, NULL_TREE))
7370 return error_mark_node;
7372 if (COMPLETE_TYPE_P (context))
7374 /* Check to see that the declaration is really present, and,
7375 possibly obtain an improved declaration. */
7376 tree fn = check_classfn (context,
7377 new_friend, NULL_TREE);
7387 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7388 template arguments, as for tsubst.
7390 Returns an appropriate tsubst'd friend type or error_mark_node on
7394 tsubst_friend_class (tree friend_tmpl, tree args)
7400 context = DECL_CONTEXT (friend_tmpl);
7404 if (TREE_CODE (context) == NAMESPACE_DECL)
7405 push_nested_namespace (context);
7407 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7410 /* Look for a class template declaration. We look for hidden names
7411 because two friend declarations of the same template are the
7412 same. For example, in:
7415 template <typename> friend class F;
7417 template <typename> struct B {
7418 template <typename> friend class F;
7421 both F templates are the same. */
7422 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7423 /*block_p=*/true, 0,
7424 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7426 /* But, if we don't find one, it might be because we're in a
7427 situation like this:
7435 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7436 for `S<int>', not the TEMPLATE_DECL. */
7437 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7439 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7440 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7443 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7445 /* The friend template has already been declared. Just
7446 check to see that the declarations match, and install any new
7447 default parameters. We must tsubst the default parameters,
7448 of course. We only need the innermost template parameters
7449 because that is all that redeclare_class_template will look
7451 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7452 > TMPL_ARGS_DEPTH (args))
7455 location_t saved_input_location;
7456 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7457 args, tf_warning_or_error);
7459 saved_input_location = input_location;
7460 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7461 redeclare_class_template (TREE_TYPE (tmpl), parms);
7462 input_location = saved_input_location;
7466 friend_type = TREE_TYPE (tmpl);
7470 /* The friend template has not already been declared. In this
7471 case, the instantiation of the template class will cause the
7472 injection of this template into the global scope. */
7473 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7474 if (tmpl == error_mark_node)
7475 return error_mark_node;
7477 /* The new TMPL is not an instantiation of anything, so we
7478 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7479 the new type because that is supposed to be the corresponding
7480 template decl, i.e., TMPL. */
7481 DECL_USE_TEMPLATE (tmpl) = 0;
7482 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7483 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7484 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7485 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7487 /* Inject this template into the global scope. */
7488 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7493 if (TREE_CODE (context) == NAMESPACE_DECL)
7494 pop_nested_namespace (context);
7496 pop_nested_class ();
7502 /* Returns zero if TYPE cannot be completed later due to circularity.
7503 Otherwise returns one. */
7506 can_complete_type_without_circularity (tree type)
7508 if (type == NULL_TREE || type == error_mark_node)
7510 else if (COMPLETE_TYPE_P (type))
7512 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7513 return can_complete_type_without_circularity (TREE_TYPE (type));
7514 else if (CLASS_TYPE_P (type)
7515 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7521 /* Apply any attributes which had to be deferred until instantiation
7522 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7523 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7526 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7527 tree args, tsubst_flags_t complain, tree in_decl)
7529 tree last_dep = NULL_TREE;
7533 for (t = attributes; t; t = TREE_CHAIN (t))
7534 if (ATTR_IS_DEPENDENT (t))
7537 attributes = copy_list (attributes);
7541 if (DECL_P (*decl_p))
7543 if (TREE_TYPE (*decl_p) == error_mark_node)
7545 p = &DECL_ATTRIBUTES (*decl_p);
7548 p = &TYPE_ATTRIBUTES (*decl_p);
7552 tree late_attrs = NULL_TREE;
7553 tree *q = &late_attrs;
7555 for (*p = attributes; *p; )
7558 if (ATTR_IS_DEPENDENT (t))
7560 *p = TREE_CHAIN (t);
7561 TREE_CHAIN (t) = NULL_TREE;
7562 /* If the first attribute argument is an identifier, don't
7563 pass it through tsubst. Attributes like mode, format,
7564 cleanup and several target specific attributes expect it
7567 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7568 && TREE_VALUE (TREE_VALUE (t))
7569 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7570 == IDENTIFIER_NODE))
7573 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7575 /*integral_constant_expression_p=*/false);
7576 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7578 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7583 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7584 /*integral_constant_expression_p=*/false);
7586 q = &TREE_CHAIN (t);
7589 p = &TREE_CHAIN (t);
7592 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7596 /* Perform (or defer) access check for typedefs that were referenced
7597 from within the template TMPL code.
7598 This is a subroutine of instantiate_template and instantiate_class_template.
7599 TMPL is the template to consider and TARGS is the list of arguments of
7603 perform_typedefs_access_check (tree tmpl, tree targs)
7605 location_t saved_location;
7607 qualified_typedef_usage_t *iter;
7610 || (!CLASS_TYPE_P (tmpl)
7611 && TREE_CODE (tmpl) != FUNCTION_DECL))
7614 saved_location = input_location;
7616 VEC_iterate (qualified_typedef_usage_t,
7617 get_types_needing_access_check (tmpl),
7621 tree type_decl = iter->typedef_decl;
7622 tree type_scope = iter->context;
7624 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7627 if (uses_template_parms (type_decl))
7628 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7629 if (uses_template_parms (type_scope))
7630 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7632 /* Make access check error messages point to the location
7633 of the use of the typedef. */
7634 input_location = iter->locus;
7635 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7636 type_decl, type_decl);
7638 input_location = saved_location;
7642 instantiate_class_template (tree type)
7644 tree templ, args, pattern, t, member;
7648 unsigned int saved_maximum_field_alignment;
7650 if (type == error_mark_node)
7651 return error_mark_node;
7653 if (TYPE_BEING_DEFINED (type)
7654 || COMPLETE_TYPE_P (type)
7655 || uses_template_parms (type))
7658 /* Figure out which template is being instantiated. */
7659 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7660 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7662 /* Determine what specialization of the original template to
7664 t = most_specialized_class (type, templ);
7665 if (t == error_mark_node)
7667 TYPE_BEING_DEFINED (type) = 1;
7668 return error_mark_node;
7672 /* This TYPE is actually an instantiation of a partial
7673 specialization. We replace the innermost set of ARGS with
7674 the arguments appropriate for substitution. For example,
7677 template <class T> struct S {};
7678 template <class T> struct S<T*> {};
7680 and supposing that we are instantiating S<int*>, ARGS will
7681 presently be {int*} -- but we need {int}. */
7682 pattern = TREE_TYPE (t);
7683 args = TREE_PURPOSE (t);
7687 pattern = TREE_TYPE (templ);
7688 args = CLASSTYPE_TI_ARGS (type);
7691 /* If the template we're instantiating is incomplete, then clearly
7692 there's nothing we can do. */
7693 if (!COMPLETE_TYPE_P (pattern))
7696 /* If we've recursively instantiated too many templates, stop. */
7697 if (! push_tinst_level (type))
7700 /* Now we're really doing the instantiation. Mark the type as in
7701 the process of being defined. */
7702 TYPE_BEING_DEFINED (type) = 1;
7704 /* We may be in the middle of deferred access check. Disable
7706 push_deferring_access_checks (dk_no_deferred);
7708 push_to_top_level ();
7709 /* Use #pragma pack from the template context. */
7710 saved_maximum_field_alignment = maximum_field_alignment;
7711 maximum_field_alignment = TYPE_PRECISION (pattern);
7713 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7715 /* Set the input location to the most specialized template definition.
7716 This is needed if tsubsting causes an error. */
7717 typedecl = TYPE_MAIN_DECL (pattern);
7718 input_location = DECL_SOURCE_LOCATION (typedecl);
7720 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7721 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7722 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7723 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7724 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7725 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7726 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7727 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7728 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7729 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7730 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7731 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7732 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7733 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7734 if (ANON_AGGR_TYPE_P (pattern))
7735 SET_ANON_AGGR_TYPE_P (type);
7736 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7738 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7739 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7742 pbinfo = TYPE_BINFO (pattern);
7744 /* We should never instantiate a nested class before its enclosing
7745 class; we need to look up the nested class by name before we can
7746 instantiate it, and that lookup should instantiate the enclosing
7748 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7749 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7750 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7752 base_list = NULL_TREE;
7753 if (BINFO_N_BASE_BINFOS (pbinfo))
7756 tree context = TYPE_CONTEXT (type);
7760 /* We must enter the scope containing the type, as that is where
7761 the accessibility of types named in dependent bases are
7763 pushed_scope = push_scope (context ? context : global_namespace);
7765 /* Substitute into each of the bases to determine the actual
7767 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7770 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7771 tree expanded_bases = NULL_TREE;
7774 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7777 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7778 args, tf_error, NULL_TREE);
7779 if (expanded_bases == error_mark_node)
7782 len = TREE_VEC_LENGTH (expanded_bases);
7785 for (idx = 0; idx < len; idx++)
7788 /* Extract the already-expanded base class. */
7789 base = TREE_VEC_ELT (expanded_bases, idx);
7791 /* Substitute to figure out the base class. */
7792 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7795 if (base == error_mark_node)
7798 base_list = tree_cons (access, base, base_list);
7799 if (BINFO_VIRTUAL_P (pbase_binfo))
7800 TREE_TYPE (base_list) = integer_type_node;
7804 /* The list is now in reverse order; correct that. */
7805 base_list = nreverse (base_list);
7808 pop_scope (pushed_scope);
7810 /* Now call xref_basetypes to set up all the base-class
7812 xref_basetypes (type, base_list);
7814 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7815 (int) ATTR_FLAG_TYPE_IN_PLACE,
7816 args, tf_error, NULL_TREE);
7818 /* Now that our base classes are set up, enter the scope of the
7819 class, so that name lookups into base classes, etc. will work
7820 correctly. This is precisely analogous to what we do in
7821 begin_class_definition when defining an ordinary non-template
7822 class, except we also need to push the enclosing classes. */
7823 push_nested_class (type);
7825 /* Now members are processed in the order of declaration. */
7826 for (member = CLASSTYPE_DECL_LIST (pattern);
7827 member; member = TREE_CHAIN (member))
7829 tree t = TREE_VALUE (member);
7831 if (TREE_PURPOSE (member))
7835 /* Build new CLASSTYPE_NESTED_UTDS. */
7838 bool class_template_p;
7840 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7841 && TYPE_LANG_SPECIFIC (t)
7842 && CLASSTYPE_IS_TEMPLATE (t));
7843 /* If the member is a class template, then -- even after
7844 substitution -- there may be dependent types in the
7845 template argument list for the class. We increment
7846 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7847 that function will assume that no types are dependent
7848 when outside of a template. */
7849 if (class_template_p)
7850 ++processing_template_decl;
7851 newtag = tsubst (t, args, tf_error, NULL_TREE);
7852 if (class_template_p)
7853 --processing_template_decl;
7854 if (newtag == error_mark_node)
7857 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7859 tree name = TYPE_IDENTIFIER (t);
7861 if (class_template_p)
7862 /* Unfortunately, lookup_template_class sets
7863 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7864 instantiation (i.e., for the type of a member
7865 template class nested within a template class.)
7866 This behavior is required for
7867 maybe_process_partial_specialization to work
7868 correctly, but is not accurate in this case;
7869 the TAG is not an instantiation of anything.
7870 (The corresponding TEMPLATE_DECL is an
7871 instantiation, but the TYPE is not.) */
7872 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7874 /* Now, we call pushtag to put this NEWTAG into the scope of
7875 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7876 pushtag calling push_template_decl. We don't have to do
7877 this for enums because it will already have been done in
7880 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7881 pushtag (name, newtag, /*tag_scope=*/ts_current);
7884 else if (TREE_CODE (t) == FUNCTION_DECL
7885 || DECL_FUNCTION_TEMPLATE_P (t))
7887 /* Build new TYPE_METHODS. */
7890 if (TREE_CODE (t) == TEMPLATE_DECL)
7891 ++processing_template_decl;
7892 r = tsubst (t, args, tf_error, NULL_TREE);
7893 if (TREE_CODE (t) == TEMPLATE_DECL)
7894 --processing_template_decl;
7895 set_current_access_from_decl (r);
7896 finish_member_declaration (r);
7900 /* Build new TYPE_FIELDS. */
7901 if (TREE_CODE (t) == STATIC_ASSERT)
7904 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7905 tf_warning_or_error, NULL_TREE,
7906 /*integral_constant_expression_p=*/true);
7907 finish_static_assert (condition,
7908 STATIC_ASSERT_MESSAGE (t),
7909 STATIC_ASSERT_SOURCE_LOCATION (t),
7912 else if (TREE_CODE (t) != CONST_DECL)
7916 /* The file and line for this declaration, to
7917 assist in error message reporting. Since we
7918 called push_tinst_level above, we don't need to
7920 input_location = DECL_SOURCE_LOCATION (t);
7922 if (TREE_CODE (t) == TEMPLATE_DECL)
7923 ++processing_template_decl;
7924 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7925 if (TREE_CODE (t) == TEMPLATE_DECL)
7926 --processing_template_decl;
7927 if (TREE_CODE (r) == VAR_DECL)
7931 [t]he initialization (and any associated
7932 side-effects) of a static data member does
7933 not occur unless the static data member is
7934 itself used in a way that requires the
7935 definition of the static data member to
7938 Therefore, we do not substitute into the
7939 initialized for the static data member here. */
7940 finish_static_data_member_decl
7943 /*init_const_expr_p=*/false,
7944 /*asmspec_tree=*/NULL_TREE,
7946 if (DECL_INITIALIZED_IN_CLASS_P (r))
7947 check_static_variable_definition (r, TREE_TYPE (r));
7949 else if (TREE_CODE (r) == FIELD_DECL)
7951 /* Determine whether R has a valid type and can be
7952 completed later. If R is invalid, then it is
7953 replaced by error_mark_node so that it will not be
7954 added to TYPE_FIELDS. */
7955 tree rtype = TREE_TYPE (r);
7956 if (can_complete_type_without_circularity (rtype))
7957 complete_type (rtype);
7959 if (!COMPLETE_TYPE_P (rtype))
7961 cxx_incomplete_type_error (r, rtype);
7962 r = error_mark_node;
7966 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7967 such a thing will already have been added to the field
7968 list by tsubst_enum in finish_member_declaration in the
7969 CLASSTYPE_NESTED_UTDS case above. */
7970 if (!(TREE_CODE (r) == TYPE_DECL
7971 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7972 && DECL_ARTIFICIAL (r)))
7974 set_current_access_from_decl (r);
7975 finish_member_declaration (r);
7982 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7984 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7986 tree friend_type = t;
7987 bool adjust_processing_template_decl = false;
7989 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7991 /* template <class T> friend class C; */
7992 friend_type = tsubst_friend_class (friend_type, args);
7993 adjust_processing_template_decl = true;
7995 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7997 /* template <class T> friend class C::D; */
7998 friend_type = tsubst (friend_type, args,
7999 tf_warning_or_error, NULL_TREE);
8000 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8001 friend_type = TREE_TYPE (friend_type);
8002 adjust_processing_template_decl = true;
8004 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
8006 /* This could be either
8010 when dependent_type_p is false or
8012 template <class U> friend class T::C;
8015 friend_type = tsubst (friend_type, args,
8016 tf_warning_or_error, NULL_TREE);
8017 /* Bump processing_template_decl for correct
8018 dependent_type_p calculation. */
8019 ++processing_template_decl;
8020 if (dependent_type_p (friend_type))
8021 adjust_processing_template_decl = true;
8022 --processing_template_decl;
8024 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8025 && hidden_name_p (TYPE_NAME (friend_type)))
8029 where C hasn't been declared yet. Let's lookup name
8030 from namespace scope directly, bypassing any name that
8031 come from dependent base class. */
8032 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8034 /* The call to xref_tag_from_type does injection for friend
8036 push_nested_namespace (ns);
8038 xref_tag_from_type (friend_type, NULL_TREE,
8039 /*tag_scope=*/ts_current);
8040 pop_nested_namespace (ns);
8042 else if (uses_template_parms (friend_type))
8043 /* friend class C<T>; */
8044 friend_type = tsubst (friend_type, args,
8045 tf_warning_or_error, NULL_TREE);
8050 where C is already declared or
8052 friend class C<int>;
8054 We don't have to do anything in these cases. */
8056 if (adjust_processing_template_decl)
8057 /* Trick make_friend_class into realizing that the friend
8058 we're adding is a template, not an ordinary class. It's
8059 important that we use make_friend_class since it will
8060 perform some error-checking and output cross-reference
8062 ++processing_template_decl;
8064 if (friend_type != error_mark_node)
8065 make_friend_class (type, friend_type, /*complain=*/false);
8067 if (adjust_processing_template_decl)
8068 --processing_template_decl;
8072 /* Build new DECL_FRIENDLIST. */
8075 /* The file and line for this declaration, to
8076 assist in error message reporting. Since we
8077 called push_tinst_level above, we don't need to
8079 input_location = DECL_SOURCE_LOCATION (t);
8081 if (TREE_CODE (t) == TEMPLATE_DECL)
8083 ++processing_template_decl;
8084 push_deferring_access_checks (dk_no_check);
8087 r = tsubst_friend_function (t, args);
8088 add_friend (type, r, /*complain=*/false);
8089 if (TREE_CODE (t) == TEMPLATE_DECL)
8091 pop_deferring_access_checks ();
8092 --processing_template_decl;
8098 /* Set the file and line number information to whatever is given for
8099 the class itself. This puts error messages involving generated
8100 implicit functions at a predictable point, and the same point
8101 that would be used for non-template classes. */
8102 input_location = DECL_SOURCE_LOCATION (typedecl);
8104 unreverse_member_declarations (type);
8105 finish_struct_1 (type);
8106 TYPE_BEING_DEFINED (type) = 0;
8108 /* Now that the class is complete, instantiate default arguments for
8109 any member functions. We don't do this earlier because the
8110 default arguments may reference members of the class. */
8111 if (!PRIMARY_TEMPLATE_P (templ))
8112 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
8113 if (TREE_CODE (t) == FUNCTION_DECL
8114 /* Implicitly generated member functions will not have template
8115 information; they are not instantiations, but instead are
8116 created "fresh" for each instantiation. */
8117 && DECL_TEMPLATE_INFO (t))
8118 tsubst_default_arguments (t);
8120 /* Some typedefs referenced from within the template code need to be access
8121 checked at template instantiation time, i.e now. These types were
8122 added to the template at parsing time. Let's get those and perform
8123 the access checks then. */
8124 perform_typedefs_access_check (pattern, args);
8125 perform_deferred_access_checks ();
8126 pop_nested_class ();
8127 maximum_field_alignment = saved_maximum_field_alignment;
8128 pop_from_top_level ();
8129 pop_deferring_access_checks ();
8132 /* The vtable for a template class can be emitted in any translation
8133 unit in which the class is instantiated. When there is no key
8134 method, however, finish_struct_1 will already have added TYPE to
8135 the keyed_classes list. */
8136 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8137 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8143 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8149 else if (TYPE_P (t))
8150 r = tsubst (t, args, complain, in_decl);
8153 r = tsubst_expr (t, args, complain, in_decl,
8154 /*integral_constant_expression_p=*/true);
8155 r = fold_non_dependent_expr (r);
8160 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8161 NONTYPE_ARGUMENT_PACK. */
8164 make_fnparm_pack (tree spec_parm)
8166 /* Collect all of the extra "packed" parameters into an
8170 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8171 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8172 int i, len = list_length (spec_parm);
8174 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8175 parmvec = make_tree_vec (len);
8176 parmtypevec = make_tree_vec (len);
8177 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
8179 TREE_VEC_ELT (parmvec, i) = spec_parm;
8180 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8183 /* Build the argument packs. */
8184 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8185 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8186 TREE_TYPE (argpack) = argtypepack;
8191 /* Substitute ARGS into T, which is an pack expansion
8192 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8193 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8194 (if only a partial substitution could be performed) or
8195 ERROR_MARK_NODE if there was an error. */
8197 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8201 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8205 bool very_local_specializations = false;
8207 gcc_assert (PACK_EXPANSION_P (t));
8208 pattern = PACK_EXPANSION_PATTERN (t);
8210 /* Determine the argument packs that will instantiate the parameter
8211 packs used in the expansion expression. While we're at it,
8212 compute the number of arguments to be expanded and make sure it
8214 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8215 pack = TREE_CHAIN (pack))
8217 tree parm_pack = TREE_VALUE (pack);
8218 tree arg_pack = NULL_TREE;
8219 tree orig_arg = NULL_TREE;
8221 if (TREE_CODE (parm_pack) == PARM_DECL)
8223 arg_pack = retrieve_local_specialization (parm_pack);
8224 if (arg_pack == NULL_TREE)
8226 /* This can happen for a parameter name used later in a function
8227 declaration (such as in a late-specified return type). Just
8228 make a dummy decl, since it's only used for its type. */
8229 gcc_assert (cp_unevaluated_operand != 0);
8230 arg_pack = tsubst_decl (parm_pack, args, complain);
8231 arg_pack = make_fnparm_pack (arg_pack);
8236 int level, idx, levels;
8237 template_parm_level_and_index (parm_pack, &level, &idx);
8239 levels = TMPL_ARGS_DEPTH (args);
8240 if (level <= levels)
8241 arg_pack = TMPL_ARG (args, level, idx);
8244 orig_arg = arg_pack;
8245 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8246 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8248 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8249 /* This can only happen if we forget to expand an argument
8250 pack somewhere else. Just return an error, silently. */
8252 result = make_tree_vec (1);
8253 TREE_VEC_ELT (result, 0) = error_mark_node;
8258 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8259 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8261 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8262 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8263 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
8264 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
8265 /* The argument pack that the parameter maps to is just an
8266 expansion of the parameter itself, such as one would
8267 find in the implicit typedef of a class inside the
8268 class itself. Consider this parameter "unsubstituted",
8269 so that we will maintain the outer pack expansion. */
8270 arg_pack = NULL_TREE;
8276 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8278 /* It's all-or-nothing with incomplete argument packs. */
8279 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8280 return error_mark_node;
8282 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8287 else if (len != my_len)
8290 /* We got explicit args for some packs but not others;
8291 do nothing now and try again after deduction. */
8293 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8294 error ("mismatched argument pack lengths while expanding "
8298 error ("mismatched argument pack lengths while expanding "
8301 return error_mark_node;
8304 /* Keep track of the parameter packs and their corresponding
8306 packs = tree_cons (parm_pack, arg_pack, packs);
8307 TREE_TYPE (packs) = orig_arg;
8310 /* We can't substitute for this parameter pack. */
8311 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8313 unsubstituted_packs);
8316 /* We cannot expand this expansion expression, because we don't have
8317 all of the argument packs we need. Substitute into the pattern
8318 and return a PACK_EXPANSION_*. The caller will need to deal with
8320 if (unsubstituted_packs)
8323 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8324 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8325 /*integral_constant_expression_p=*/false);
8327 new_pat = tsubst (pattern, args, complain, in_decl);
8328 return make_pack_expansion (new_pat);
8331 /* We could not find any argument packs that work. */
8333 return error_mark_node;
8335 if (!local_specializations)
8337 /* We're in a late-specified return type, so we don't have a local
8338 specializations table. Create one for doing this expansion. */
8339 very_local_specializations = true;
8340 local_specializations = htab_create (37,
8341 hash_local_specialization,
8342 eq_local_specializations,
8346 /* For each argument in each argument pack, substitute into the
8348 result = make_tree_vec (len + incomplete);
8349 for (i = 0; i < len + incomplete; ++i)
8351 /* For parameter pack, change the substitution of the parameter
8352 pack to the ith argument in its argument pack, then expand
8354 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8356 tree parm = TREE_PURPOSE (pack);
8358 if (TREE_CODE (parm) == PARM_DECL)
8360 /* Select the Ith argument from the pack. */
8361 tree arg = make_node (ARGUMENT_PACK_SELECT);
8362 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8363 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8365 register_local_specialization (arg, parm);
8371 template_parm_level_and_index (parm, &level, &idx);
8375 /* Select the Ith argument from the pack. */
8376 value = make_node (ARGUMENT_PACK_SELECT);
8377 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8378 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8381 /* Update the corresponding argument. */
8382 TMPL_ARG (args, level, idx) = value;
8386 /* Substitute into the PATTERN with the altered arguments. */
8387 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8388 TREE_VEC_ELT (result, i) =
8389 tsubst_expr (pattern, args, complain, in_decl,
8390 /*integral_constant_expression_p=*/false);
8392 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8395 /* When we have incomplete argument packs, the last "expanded"
8396 result is itself a pack expansion, which allows us
8397 to deduce more arguments. */
8398 TREE_VEC_ELT (result, i) =
8399 make_pack_expansion (TREE_VEC_ELT (result, i));
8401 if (TREE_VEC_ELT (result, i) == error_mark_node)
8403 result = error_mark_node;
8408 /* Update ARGS to restore the substitution from parameter packs to
8409 their argument packs. */
8410 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8412 tree parm = TREE_PURPOSE (pack);
8414 if (TREE_CODE (parm) == PARM_DECL)
8415 register_local_specialization (TREE_TYPE (pack), parm);
8419 template_parm_level_and_index (parm, &level, &idx);
8421 /* Update the corresponding argument. */
8422 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8423 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8426 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8430 if (very_local_specializations)
8432 htab_delete (local_specializations);
8433 local_specializations = NULL;
8439 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8440 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8441 parameter packs; all parms generated from a function parameter pack will
8442 have the same DECL_PARM_INDEX. */
8445 get_pattern_parm (tree parm, tree tmpl)
8447 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8450 if (DECL_ARTIFICIAL (parm))
8452 for (patparm = DECL_ARGUMENTS (pattern);
8453 patparm; patparm = TREE_CHAIN (patparm))
8454 if (DECL_ARTIFICIAL (patparm)
8455 && DECL_NAME (parm) == DECL_NAME (patparm))
8460 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8461 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8462 gcc_assert (DECL_PARM_INDEX (patparm)
8463 == DECL_PARM_INDEX (parm));
8469 /* Substitute ARGS into the vector or list of template arguments T. */
8472 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8475 int len = TREE_VEC_LENGTH (t);
8476 int need_new = 0, i, expanded_len_adjust = 0, out;
8477 tree *elts = (tree *) alloca (len * sizeof (tree));
8479 for (i = 0; i < len; i++)
8481 tree orig_arg = TREE_VEC_ELT (t, i);
8484 if (TREE_CODE (orig_arg) == TREE_VEC)
8485 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8486 else if (PACK_EXPANSION_P (orig_arg))
8488 /* Substitute into an expansion expression. */
8489 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8491 if (TREE_CODE (new_arg) == TREE_VEC)
8492 /* Add to the expanded length adjustment the number of
8493 expanded arguments. We subtract one from this
8494 measurement, because the argument pack expression
8495 itself is already counted as 1 in
8496 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8497 the argument pack is empty. */
8498 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8500 else if (ARGUMENT_PACK_P (orig_arg))
8502 /* Substitute into each of the arguments. */
8503 new_arg = TYPE_P (orig_arg)
8504 ? cxx_make_type (TREE_CODE (orig_arg))
8505 : make_node (TREE_CODE (orig_arg));
8507 SET_ARGUMENT_PACK_ARGS (
8509 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8510 args, complain, in_decl));
8512 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8513 new_arg = error_mark_node;
8515 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8516 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8518 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8520 if (TREE_TYPE (new_arg) == error_mark_node)
8521 new_arg = error_mark_node;
8525 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8527 if (new_arg == error_mark_node)
8528 return error_mark_node;
8531 if (new_arg != orig_arg)
8538 /* Make space for the expanded arguments coming from template
8540 t = make_tree_vec (len + expanded_len_adjust);
8541 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
8542 arguments for a member template.
8543 In that case each TREE_VEC in ORIG_T represents a level of template
8544 arguments, and ORIG_T won't carry any non defaulted argument count.
8545 It will rather be the nested TREE_VECs that will carry one.
8546 In other words, ORIG_T carries a non defaulted argument count only
8547 if it doesn't contain any nested TREE_VEC. */
8548 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
8550 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
8551 count += expanded_len_adjust;
8552 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
8554 for (i = 0, out = 0; i < len; i++)
8556 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8557 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8558 && TREE_CODE (elts[i]) == TREE_VEC)
8562 /* Now expand the template argument pack "in place". */
8563 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8564 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8568 TREE_VEC_ELT (t, out) = elts[i];
8576 /* Return the result of substituting ARGS into the template parameters
8577 given by PARMS. If there are m levels of ARGS and m + n levels of
8578 PARMS, then the result will contain n levels of PARMS. For
8579 example, if PARMS is `template <class T> template <class U>
8580 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8581 result will be `template <int*, double, class V>'. */
8584 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8589 /* When substituting into a template, we must set
8590 PROCESSING_TEMPLATE_DECL as the template parameters may be
8591 dependent if they are based on one-another, and the dependency
8592 predicates are short-circuit outside of templates. */
8593 ++processing_template_decl;
8595 for (new_parms = &r;
8596 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8597 new_parms = &(TREE_CHAIN (*new_parms)),
8598 parms = TREE_CHAIN (parms))
8601 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8604 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8610 if (parms == error_mark_node)
8613 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8615 if (tuple == error_mark_node)
8618 default_value = TREE_PURPOSE (tuple);
8619 parm_decl = TREE_VALUE (tuple);
8621 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8622 if (TREE_CODE (parm_decl) == PARM_DECL
8623 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8624 parm_decl = error_mark_node;
8625 default_value = tsubst_template_arg (default_value, args,
8626 complain, NULL_TREE);
8628 tuple = build_tree_list (default_value, parm_decl);
8629 TREE_VEC_ELT (new_vec, i) = tuple;
8633 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8634 - TMPL_ARGS_DEPTH (args)),
8635 new_vec, NULL_TREE);
8638 --processing_template_decl;
8643 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8644 type T. If T is not an aggregate or enumeration type, it is
8645 handled as if by tsubst. IN_DECL is as for tsubst. If
8646 ENTERING_SCOPE is nonzero, T is the context for a template which
8647 we are presently tsubst'ing. Return the substituted value. */
8650 tsubst_aggr_type (tree t,
8652 tsubst_flags_t complain,
8659 switch (TREE_CODE (t))
8662 if (TYPE_PTRMEMFUNC_P (t))
8663 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8665 /* Else fall through. */
8668 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8673 int saved_unevaluated_operand;
8674 int saved_inhibit_evaluation_warnings;
8676 /* In "sizeof(X<I>)" we need to evaluate "I". */
8677 saved_unevaluated_operand = cp_unevaluated_operand;
8678 cp_unevaluated_operand = 0;
8679 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8680 c_inhibit_evaluation_warnings = 0;
8682 /* First, determine the context for the type we are looking
8684 context = TYPE_CONTEXT (t);
8687 context = tsubst_aggr_type (context, args, complain,
8688 in_decl, /*entering_scope=*/1);
8689 /* If context is a nested class inside a class template,
8690 it may still need to be instantiated (c++/33959). */
8691 if (TYPE_P (context))
8692 context = complete_type (context);
8695 /* Then, figure out what arguments are appropriate for the
8696 type we are trying to find. For example, given:
8698 template <class T> struct S;
8699 template <class T, class U> void f(T, U) { S<U> su; }
8701 and supposing that we are instantiating f<int, double>,
8702 then our ARGS will be {int, double}, but, when looking up
8703 S we only want {double}. */
8704 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8706 if (argvec == error_mark_node)
8707 r = error_mark_node;
8710 r = lookup_template_class (t, argvec, in_decl, context,
8711 entering_scope, complain);
8712 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8715 cp_unevaluated_operand = saved_unevaluated_operand;
8716 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8721 /* This is not a template type, so there's nothing to do. */
8725 return tsubst (t, args, complain, in_decl);
8729 /* Substitute into the default argument ARG (a default argument for
8730 FN), which has the indicated TYPE. */
8733 tsubst_default_argument (tree fn, tree type, tree arg)
8735 tree saved_class_ptr = NULL_TREE;
8736 tree saved_class_ref = NULL_TREE;
8738 /* This default argument came from a template. Instantiate the
8739 default argument here, not in tsubst. In the case of
8748 we must be careful to do name lookup in the scope of S<T>,
8749 rather than in the current class. */
8750 push_access_scope (fn);
8751 /* The "this" pointer is not valid in a default argument. */
8754 saved_class_ptr = current_class_ptr;
8755 cp_function_chain->x_current_class_ptr = NULL_TREE;
8756 saved_class_ref = current_class_ref;
8757 cp_function_chain->x_current_class_ref = NULL_TREE;
8760 push_deferring_access_checks(dk_no_deferred);
8761 /* The default argument expression may cause implicitly defined
8762 member functions to be synthesized, which will result in garbage
8763 collection. We must treat this situation as if we were within
8764 the body of function so as to avoid collecting live data on the
8767 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8768 tf_warning_or_error, NULL_TREE,
8769 /*integral_constant_expression_p=*/false);
8771 pop_deferring_access_checks();
8773 /* Restore the "this" pointer. */
8776 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8777 cp_function_chain->x_current_class_ref = saved_class_ref;
8780 /* Make sure the default argument is reasonable. */
8781 arg = check_default_argument (type, arg);
8783 pop_access_scope (fn);
8788 /* Substitute into all the default arguments for FN. */
8791 tsubst_default_arguments (tree fn)
8796 tmpl_args = DECL_TI_ARGS (fn);
8798 /* If this function is not yet instantiated, we certainly don't need
8799 its default arguments. */
8800 if (uses_template_parms (tmpl_args))
8803 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8805 arg = TREE_CHAIN (arg))
8806 if (TREE_PURPOSE (arg))
8807 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8809 TREE_PURPOSE (arg));
8812 /* Substitute the ARGS into the T, which is a _DECL. Return the
8813 result of the substitution. Issue error and warning messages under
8814 control of COMPLAIN. */
8817 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8819 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8820 location_t saved_loc;
8825 /* Set the filename and linenumber to improve error-reporting. */
8826 saved_loc = input_location;
8827 input_location = DECL_SOURCE_LOCATION (t);
8829 switch (TREE_CODE (t))
8833 /* We can get here when processing a member function template,
8834 member class template, or template template parameter. */
8835 tree decl = DECL_TEMPLATE_RESULT (t);
8840 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8842 /* Template template parameter is treated here. */
8843 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8844 if (new_type == error_mark_node)
8845 RETURN (error_mark_node);
8848 TREE_CHAIN (r) = NULL_TREE;
8849 TREE_TYPE (r) = new_type;
8850 DECL_TEMPLATE_RESULT (r)
8851 = build_decl (DECL_SOURCE_LOCATION (decl),
8852 TYPE_DECL, DECL_NAME (decl), new_type);
8853 DECL_TEMPLATE_PARMS (r)
8854 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8856 TYPE_NAME (new_type) = r;
8860 /* We might already have an instance of this template.
8861 The ARGS are for the surrounding class type, so the
8862 full args contain the tsubst'd args for the context,
8863 plus the innermost args from the template decl. */
8864 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8865 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8866 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8867 /* Because this is a template, the arguments will still be
8868 dependent, even after substitution. If
8869 PROCESSING_TEMPLATE_DECL is not set, the dependency
8870 predicates will short-circuit. */
8871 ++processing_template_decl;
8872 full_args = tsubst_template_args (tmpl_args, args,
8874 --processing_template_decl;
8875 if (full_args == error_mark_node)
8876 RETURN (error_mark_node);
8878 /* If this is a default template template argument,
8879 tsubst might not have changed anything. */
8880 if (full_args == tmpl_args)
8883 hash = hash_tmpl_and_args (t, full_args);
8884 spec = retrieve_specialization (t, full_args, hash);
8885 if (spec != NULL_TREE)
8891 /* Make a new template decl. It will be similar to the
8892 original, but will record the current template arguments.
8893 We also create a new function declaration, which is just
8894 like the old one, but points to this new template, rather
8895 than the old one. */
8897 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8898 TREE_CHAIN (r) = NULL_TREE;
8900 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
8902 if (TREE_CODE (decl) == TYPE_DECL)
8905 ++processing_template_decl;
8906 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8907 --processing_template_decl;
8908 if (new_type == error_mark_node)
8909 RETURN (error_mark_node);
8911 TREE_TYPE (r) = new_type;
8912 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8913 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8914 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8915 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8920 ++processing_template_decl;
8921 new_decl = tsubst (decl, args, complain, in_decl);
8922 --processing_template_decl;
8923 if (new_decl == error_mark_node)
8924 RETURN (error_mark_node);
8926 DECL_TEMPLATE_RESULT (r) = new_decl;
8927 DECL_TI_TEMPLATE (new_decl) = r;
8928 TREE_TYPE (r) = TREE_TYPE (new_decl);
8929 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8930 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8933 SET_DECL_IMPLICIT_INSTANTIATION (r);
8934 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8935 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8937 /* The template parameters for this new template are all the
8938 template parameters for the old template, except the
8939 outermost level of parameters. */
8940 DECL_TEMPLATE_PARMS (r)
8941 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8944 if (PRIMARY_TEMPLATE_P (t))
8945 DECL_PRIMARY_TEMPLATE (r) = r;
8947 if (TREE_CODE (decl) != TYPE_DECL)
8948 /* Record this non-type partial instantiation. */
8949 register_specialization (r, t,
8950 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8958 tree argvec = NULL_TREE;
8966 /* Nobody should be tsubst'ing into non-template functions. */
8967 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8969 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8974 /* If T is not dependent, just return it. We have to
8975 increment PROCESSING_TEMPLATE_DECL because
8976 value_dependent_expression_p assumes that nothing is
8977 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8978 ++processing_template_decl;
8979 dependent_p = value_dependent_expression_p (t);
8980 --processing_template_decl;
8984 /* Calculate the most general template of which R is a
8985 specialization, and the complete set of arguments used to
8987 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8988 argvec = tsubst_template_args (DECL_TI_ARGS
8989 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8990 args, complain, in_decl);
8992 /* Check to see if we already have this specialization. */
8993 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8994 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9002 /* We can see more levels of arguments than parameters if
9003 there was a specialization of a member template, like
9006 template <class T> struct S { template <class U> void f(); }
9007 template <> template <class U> void S<int>::f(U);
9009 Here, we'll be substituting into the specialization,
9010 because that's where we can find the code we actually
9011 want to generate, but we'll have enough arguments for
9012 the most general template.
9014 We also deal with the peculiar case:
9016 template <class T> struct S {
9017 template <class U> friend void f();
9019 template <class U> void f() {}
9021 template void f<double>();
9023 Here, the ARGS for the instantiation of will be {int,
9024 double}. But, we only need as many ARGS as there are
9025 levels of template parameters in CODE_PATTERN. We are
9026 careful not to get fooled into reducing the ARGS in
9029 template <class T> struct S { template <class U> void f(U); }
9030 template <class T> template <> void S<T>::f(int) {}
9032 which we can spot because the pattern will be a
9033 specialization in this case. */
9034 args_depth = TMPL_ARGS_DEPTH (args);
9036 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
9037 if (args_depth > parms_depth
9038 && !DECL_TEMPLATE_SPECIALIZATION (t))
9039 args = get_innermost_template_args (args, parms_depth);
9043 /* This special case arises when we have something like this:
9045 template <class T> struct S {
9046 friend void f<int>(int, double);
9049 Here, the DECL_TI_TEMPLATE for the friend declaration
9050 will be an IDENTIFIER_NODE. We are being called from
9051 tsubst_friend_function, and we want only to create a
9052 new decl (R) with appropriate types so that we can call
9053 determine_specialization. */
9054 gen_tmpl = NULL_TREE;
9057 if (DECL_CLASS_SCOPE_P (t))
9059 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9063 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9064 complain, t, /*entering_scope=*/1);
9069 ctx = DECL_CONTEXT (t);
9071 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9072 if (type == error_mark_node)
9073 RETURN (error_mark_node);
9075 /* We do NOT check for matching decls pushed separately at this
9076 point, as they may not represent instantiations of this
9077 template, and in any case are considered separate under the
9080 DECL_USE_TEMPLATE (r) = 0;
9081 TREE_TYPE (r) = type;
9082 /* Clear out the mangled name and RTL for the instantiation. */
9083 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9084 SET_DECL_RTL (r, NULL_RTX);
9085 /* Leave DECL_INITIAL set on deleted instantiations. */
9086 if (!DECL_DELETED_FN (r))
9087 DECL_INITIAL (r) = NULL_TREE;
9088 DECL_CONTEXT (r) = ctx;
9090 if (member && DECL_CONV_FN_P (r))
9091 /* Type-conversion operator. Reconstruct the name, in
9092 case it's the name of one of the template's parameters. */
9093 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9095 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9097 DECL_RESULT (r) = NULL_TREE;
9099 TREE_STATIC (r) = 0;
9100 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9101 DECL_EXTERNAL (r) = 1;
9102 /* If this is an instantiation of a function with internal
9103 linkage, we already know what object file linkage will be
9104 assigned to the instantiation. */
9105 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9106 DECL_DEFER_OUTPUT (r) = 0;
9107 TREE_CHAIN (r) = NULL_TREE;
9108 DECL_PENDING_INLINE_INFO (r) = 0;
9109 DECL_PENDING_INLINE_P (r) = 0;
9110 DECL_SAVED_TREE (r) = NULL_TREE;
9111 DECL_STRUCT_FUNCTION (r) = NULL;
9113 /* We'll re-clone as appropriate in instantiate_template. */
9114 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9116 /* If we aren't complaining now, return on error before we register
9117 the specialization so that we'll complain eventually. */
9118 if ((complain & tf_error) == 0
9119 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9120 && !grok_op_properties (r, /*complain=*/false))
9121 RETURN (error_mark_node);
9123 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9124 this in the special friend case mentioned above where
9125 GEN_TMPL is NULL. */
9128 DECL_TEMPLATE_INFO (r)
9129 = build_template_info (gen_tmpl, argvec);
9130 SET_DECL_IMPLICIT_INSTANTIATION (r);
9131 register_specialization (r, gen_tmpl, argvec, false, hash);
9133 /* We're not supposed to instantiate default arguments
9134 until they are called, for a template. But, for a
9137 template <class T> void f ()
9138 { extern void g(int i = T()); }
9140 we should do the substitution when the template is
9141 instantiated. We handle the member function case in
9142 instantiate_class_template since the default arguments
9143 might refer to other members of the class. */
9145 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9146 && !uses_template_parms (argvec))
9147 tsubst_default_arguments (r);
9150 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9152 /* Copy the list of befriending classes. */
9153 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9155 friends = &TREE_CHAIN (*friends))
9157 *friends = copy_node (*friends);
9158 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9163 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9165 maybe_retrofit_in_chrg (r);
9166 if (DECL_CONSTRUCTOR_P (r))
9167 grok_ctor_properties (ctx, r);
9168 /* If this is an instantiation of a member template, clone it.
9169 If it isn't, that'll be handled by
9170 clone_constructors_and_destructors. */
9171 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9172 clone_function_decl (r, /*update_method_vec_p=*/0);
9174 else if ((complain & tf_error) != 0
9175 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9176 && !grok_op_properties (r, /*complain=*/true))
9177 RETURN (error_mark_node);
9179 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9180 SET_DECL_FRIEND_CONTEXT (r,
9181 tsubst (DECL_FRIEND_CONTEXT (t),
9182 args, complain, in_decl));
9184 /* Possibly limit visibility based on template args. */
9185 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9186 if (DECL_VISIBILITY_SPECIFIED (t))
9188 DECL_VISIBILITY_SPECIFIED (r) = 0;
9190 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9192 determine_visibility (r);
9193 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9194 && !processing_template_decl)
9195 defaulted_late_check (r);
9197 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9198 args, complain, in_decl);
9204 tree type = NULL_TREE;
9206 tree expanded_types = NULL_TREE;
9207 tree prev_r = NULL_TREE;
9208 tree first_r = NULL_TREE;
9210 if (FUNCTION_PARAMETER_PACK_P (t))
9212 /* If there is a local specialization that isn't a
9213 parameter pack, it means that we're doing a "simple"
9214 substitution from inside tsubst_pack_expansion. Just
9215 return the local specialization (which will be a single
9217 tree spec = retrieve_local_specialization (t);
9219 && TREE_CODE (spec) == PARM_DECL
9220 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9223 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9224 the parameters in this function parameter pack. */
9225 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9227 if (TREE_CODE (expanded_types) == TREE_VEC)
9229 len = TREE_VEC_LENGTH (expanded_types);
9231 /* Zero-length parameter packs are boring. Just substitute
9234 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9239 /* All we did was update the type. Make a note of that. */
9240 type = expanded_types;
9241 expanded_types = NULL_TREE;
9245 /* Loop through all of the parameter's we'll build. When T is
9246 a function parameter pack, LEN is the number of expanded
9247 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9249 for (i = 0; i < len; ++i)
9253 if (DECL_TEMPLATE_PARM_P (t))
9254 SET_DECL_TEMPLATE_PARM_P (r);
9256 /* An argument of a function parameter pack is not a parameter
9258 FUNCTION_PARAMETER_PACK_P (r) = false;
9261 /* We're on the Ith parameter of the function parameter
9264 /* Get the Ith type. */
9265 type = TREE_VEC_ELT (expanded_types, i);
9268 /* Rename the parameter to include the index. */
9270 make_ith_pack_parameter_name (DECL_NAME (r), i);
9273 /* We're dealing with a normal parameter. */
9274 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9276 type = type_decays_to (type);
9277 TREE_TYPE (r) = type;
9278 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9280 if (DECL_INITIAL (r))
9282 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9283 DECL_INITIAL (r) = TREE_TYPE (r);
9285 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9289 DECL_CONTEXT (r) = NULL_TREE;
9291 if (!DECL_TEMPLATE_PARM_P (r))
9292 DECL_ARG_TYPE (r) = type_passed_as (type);
9294 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9295 args, complain, in_decl);
9297 /* Keep track of the first new parameter we
9298 generate. That's what will be returned to the
9303 /* Build a proper chain of parameters when substituting
9304 into a function parameter pack. */
9306 TREE_CHAIN (prev_r) = r;
9310 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
9311 complain, TREE_CHAIN (t));
9313 /* FIRST_R contains the start of the chain we've built. */
9323 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9324 if (type == error_mark_node)
9325 RETURN (error_mark_node);
9326 TREE_TYPE (r) = type;
9327 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9329 /* DECL_INITIAL gives the number of bits in a bit-field. */
9331 = tsubst_expr (DECL_INITIAL (t), args,
9333 /*integral_constant_expression_p=*/true);
9334 /* We don't have to set DECL_CONTEXT here; it is set by
9335 finish_member_declaration. */
9336 TREE_CHAIN (r) = NULL_TREE;
9337 if (VOID_TYPE_P (type))
9338 error ("instantiation of %q+D as type %qT", r, type);
9340 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9341 args, complain, in_decl);
9346 /* We reach here only for member using decls. */
9347 if (DECL_DEPENDENT_P (t))
9349 r = do_class_using_decl
9350 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9351 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9353 r = error_mark_node;
9356 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9357 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9363 TREE_CHAIN (r) = NULL_TREE;
9370 tree argvec = NULL_TREE;
9371 tree gen_tmpl = NULL_TREE;
9373 tree tmpl = NULL_TREE;
9375 tree type = NULL_TREE;
9378 if (TREE_CODE (t) == TYPE_DECL
9379 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9381 /* If this is the canonical decl, we don't have to
9382 mess with instantiations, and often we can't (for
9383 typename, template type parms and such). Note that
9384 TYPE_NAME is not correct for the above test if
9385 we've copied the type for a typedef. */
9386 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9387 if (type == error_mark_node)
9388 RETURN (error_mark_node);
9389 r = TYPE_NAME (type);
9393 /* Check to see if we already have the specialization we
9396 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9398 /* T is a static data member or namespace-scope entity.
9399 We have to substitute into namespace-scope variables
9400 (even though such entities are never templates) because
9403 template <class T> void f() { extern T t; }
9405 where the entity referenced is not known until
9406 instantiation time. */
9408 ctx = DECL_CONTEXT (t);
9409 if (DECL_CLASS_SCOPE_P (t))
9411 ctx = tsubst_aggr_type (ctx, args,
9413 in_decl, /*entering_scope=*/1);
9414 /* If CTX is unchanged, then T is in fact the
9415 specialization we want. That situation occurs when
9416 referencing a static data member within in its own
9417 class. We can use pointer equality, rather than
9418 same_type_p, because DECL_CONTEXT is always
9420 if (ctx == DECL_CONTEXT (t))
9426 tmpl = DECL_TI_TEMPLATE (t);
9427 gen_tmpl = most_general_template (tmpl);
9428 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9429 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9430 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9435 /* A local variable. */
9437 /* Subsequent calls to pushdecl will fill this in. */
9439 spec = retrieve_local_specialization (t);
9441 /* If we already have the specialization we need, there is
9442 nothing more to do. */
9449 /* Create a new node for the specialization we need. */
9451 if (type == NULL_TREE)
9453 if (is_typedef_decl (t))
9454 type = DECL_ORIGINAL_TYPE (t);
9456 type = TREE_TYPE (t);
9457 type = tsubst (type, args, complain, in_decl);
9459 if (TREE_CODE (r) == VAR_DECL)
9461 /* Even if the original location is out of scope, the
9462 newly substituted one is not. */
9463 DECL_DEAD_FOR_LOCAL (r) = 0;
9464 DECL_INITIALIZED_P (r) = 0;
9465 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9466 if (type == error_mark_node)
9467 RETURN (error_mark_node);
9468 if (TREE_CODE (type) == FUNCTION_TYPE)
9470 /* It may seem that this case cannot occur, since:
9475 declares a function, not a variable. However:
9478 template <typename T> void g() { T t; }
9479 template void g<f>();
9481 is an attempt to declare a variable with function
9483 error ("variable %qD has function type",
9484 /* R is not yet sufficiently initialized, so we
9485 just use its name. */
9487 RETURN (error_mark_node);
9489 type = complete_type (type);
9490 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9491 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9492 type = check_var_type (DECL_NAME (r), type);
9494 if (DECL_HAS_VALUE_EXPR_P (t))
9496 tree ve = DECL_VALUE_EXPR (t);
9497 ve = tsubst_expr (ve, args, complain, in_decl,
9498 /*constant_expression_p=*/false);
9499 SET_DECL_VALUE_EXPR (r, ve);
9502 else if (DECL_SELF_REFERENCE_P (t))
9503 SET_DECL_SELF_REFERENCE_P (r);
9504 TREE_TYPE (r) = type;
9505 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9506 DECL_CONTEXT (r) = ctx;
9507 /* Clear out the mangled name and RTL for the instantiation. */
9508 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9509 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9510 SET_DECL_RTL (r, NULL_RTX);
9511 /* The initializer must not be expanded until it is required;
9513 DECL_INITIAL (r) = NULL_TREE;
9514 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9515 SET_DECL_RTL (r, NULL_RTX);
9516 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9517 if (TREE_CODE (r) == VAR_DECL)
9519 /* Possibly limit visibility based on template args. */
9520 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9521 if (DECL_VISIBILITY_SPECIFIED (t))
9523 DECL_VISIBILITY_SPECIFIED (r) = 0;
9525 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9527 determine_visibility (r);
9532 /* A static data member declaration is always marked
9533 external when it is declared in-class, even if an
9534 initializer is present. We mimic the non-template
9536 DECL_EXTERNAL (r) = 1;
9538 register_specialization (r, gen_tmpl, argvec, false, hash);
9539 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
9540 SET_DECL_IMPLICIT_INSTANTIATION (r);
9542 else if (cp_unevaluated_operand)
9544 /* We're substituting this var in a decltype outside of its
9545 scope, such as for a lambda return type. Don't add it to
9546 local_specializations, do perform auto deduction. */
9547 tree auto_node = type_uses_auto (type);
9549 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9550 /*constant_expression_p=*/false);
9552 if (auto_node && init && describable_type (init))
9554 type = do_auto_deduction (type, init, auto_node);
9555 TREE_TYPE (r) = type;
9559 register_local_specialization (r, t);
9561 TREE_CHAIN (r) = NULL_TREE;
9563 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9565 args, complain, in_decl);
9567 /* Preserve a typedef that names a type. */
9568 if (is_typedef_decl (r))
9570 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
9571 set_underlying_type (r);
9584 /* Restore the file and line information. */
9585 input_location = saved_loc;
9590 /* Substitute into the ARG_TYPES of a function type. */
9593 tsubst_arg_types (tree arg_types,
9595 tsubst_flags_t complain,
9598 tree remaining_arg_types;
9599 tree type = NULL_TREE;
9601 tree expanded_args = NULL_TREE;
9604 if (!arg_types || arg_types == void_list_node)
9607 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9608 args, complain, in_decl);
9609 if (remaining_arg_types == error_mark_node)
9610 return error_mark_node;
9612 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9614 /* For a pack expansion, perform substitution on the
9615 entire expression. Later on, we'll handle the arguments
9617 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9618 args, complain, in_decl);
9620 if (TREE_CODE (expanded_args) == TREE_VEC)
9621 /* So that we'll spin through the parameters, one by one. */
9622 i = TREE_VEC_LENGTH (expanded_args);
9625 /* We only partially substituted into the parameter
9626 pack. Our type is TYPE_PACK_EXPANSION. */
9627 type = expanded_args;
9628 expanded_args = NULL_TREE;
9636 type = TREE_VEC_ELT (expanded_args, i);
9638 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9640 if (type == error_mark_node)
9641 return error_mark_node;
9642 if (VOID_TYPE_P (type))
9644 if (complain & tf_error)
9646 error ("invalid parameter type %qT", type);
9648 error ("in declaration %q+D", in_decl);
9650 return error_mark_node;
9653 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9654 top-level qualifiers as required. */
9655 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9657 /* We do not substitute into default arguments here. The standard
9658 mandates that they be instantiated only when needed, which is
9659 done in build_over_call. */
9660 default_arg = TREE_PURPOSE (arg_types);
9662 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9664 /* We've instantiated a template before its default arguments
9665 have been parsed. This can happen for a nested template
9666 class, and is not an error unless we require the default
9667 argument in a call of this function. */
9668 remaining_arg_types =
9669 tree_cons (default_arg, type, remaining_arg_types);
9670 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9671 remaining_arg_types);
9674 remaining_arg_types =
9675 hash_tree_cons (default_arg, type, remaining_arg_types);
9678 return remaining_arg_types;
9681 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9682 *not* handle the exception-specification for FNTYPE, because the
9683 initial substitution of explicitly provided template parameters
9684 during argument deduction forbids substitution into the
9685 exception-specification:
9689 All references in the function type of the function template to the
9690 corresponding template parameters are replaced by the specified tem-
9691 plate argument values. If a substitution in a template parameter or
9692 in the function type of the function template results in an invalid
9693 type, type deduction fails. [Note: The equivalent substitution in
9694 exception specifications is done only when the function is instanti-
9695 ated, at which point a program is ill-formed if the substitution
9696 results in an invalid type.] */
9699 tsubst_function_type (tree t,
9701 tsubst_flags_t complain,
9708 /* The TYPE_CONTEXT is not used for function/method types. */
9709 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9711 /* Substitute the return type. */
9712 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9713 if (return_type == error_mark_node)
9714 return error_mark_node;
9715 /* The standard does not presently indicate that creation of a
9716 function type with an invalid return type is a deduction failure.
9717 However, that is clearly analogous to creating an array of "void"
9718 or a reference to a reference. This is core issue #486. */
9719 if (TREE_CODE (return_type) == ARRAY_TYPE
9720 || TREE_CODE (return_type) == FUNCTION_TYPE)
9722 if (complain & tf_error)
9724 if (TREE_CODE (return_type) == ARRAY_TYPE)
9725 error ("function returning an array");
9727 error ("function returning a function");
9729 return error_mark_node;
9732 /* Substitute the argument types. */
9733 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9735 if (arg_types == error_mark_node)
9736 return error_mark_node;
9738 /* Construct a new type node and return it. */
9739 if (TREE_CODE (t) == FUNCTION_TYPE)
9740 fntype = build_function_type (return_type, arg_types);
9743 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9744 if (! MAYBE_CLASS_TYPE_P (r))
9748 Type deduction may fail for any of the following
9751 -- Attempting to create "pointer to member of T" when T
9752 is not a class type. */
9753 if (complain & tf_error)
9754 error ("creating pointer to member function of non-class type %qT",
9756 return error_mark_node;
9759 fntype = build_method_type_directly (r, return_type,
9760 TREE_CHAIN (arg_types));
9762 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9763 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9768 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9769 ARGS into that specification, and return the substituted
9770 specification. If there is no specification, return NULL_TREE. */
9773 tsubst_exception_specification (tree fntype,
9775 tsubst_flags_t complain,
9781 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9782 new_specs = NULL_TREE;
9785 if (! TREE_VALUE (specs))
9792 tree expanded_specs = NULL_TREE;
9794 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9796 /* Expand the pack expansion type. */
9797 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9801 if (expanded_specs == error_mark_node)
9802 return error_mark_node;
9803 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9804 len = TREE_VEC_LENGTH (expanded_specs);
9807 /* We're substituting into a member template, so
9808 we got a TYPE_PACK_EXPANSION back. Add that
9809 expansion and move on. */
9810 gcc_assert (TREE_CODE (expanded_specs)
9811 == TYPE_PACK_EXPANSION);
9812 new_specs = add_exception_specifier (new_specs,
9815 specs = TREE_CHAIN (specs);
9820 for (i = 0; i < len; ++i)
9823 spec = TREE_VEC_ELT (expanded_specs, i);
9825 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9826 if (spec == error_mark_node)
9828 new_specs = add_exception_specifier (new_specs, spec,
9832 specs = TREE_CHAIN (specs);
9838 /* Take the tree structure T and replace template parameters used
9839 therein with the argument vector ARGS. IN_DECL is an associated
9840 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9841 Issue error and warning messages under control of COMPLAIN. Note
9842 that we must be relatively non-tolerant of extensions here, in
9843 order to preserve conformance; if we allow substitutions that
9844 should not be allowed, we may allow argument deductions that should
9845 not succeed, and therefore report ambiguous overload situations
9846 where there are none. In theory, we could allow the substitution,
9847 but indicate that it should have failed, and allow our caller to
9848 make sure that the right thing happens, but we don't try to do this
9851 This function is used for dealing with types, decls and the like;
9852 for expressions, use tsubst_expr or tsubst_copy. */
9855 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9859 if (t == NULL_TREE || t == error_mark_node
9860 || t == integer_type_node
9861 || t == void_type_node
9862 || t == char_type_node
9863 || t == unknown_type_node
9864 || TREE_CODE (t) == NAMESPACE_DECL)
9868 return tsubst_decl (t, args, complain);
9870 if (args == NULL_TREE)
9873 if (TREE_CODE (t) == IDENTIFIER_NODE)
9874 type = IDENTIFIER_TYPE_VALUE (t);
9876 type = TREE_TYPE (t);
9878 gcc_assert (type != unknown_type_node);
9880 /* Reuse typedefs. We need to do this to handle dependent attributes,
9881 such as attribute aligned. */
9884 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9886 tree decl = TYPE_NAME (t);
9888 if (DECL_CLASS_SCOPE_P (decl)
9889 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9890 && uses_template_parms (DECL_CONTEXT (decl)))
9892 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9893 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9894 r = retrieve_specialization (tmpl, gen_args, 0);
9896 else if (DECL_FUNCTION_SCOPE_P (decl)
9897 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9898 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9899 r = retrieve_local_specialization (decl);
9901 /* The typedef is from a non-template context. */
9907 r = cp_build_qualified_type_real
9908 (r, cp_type_quals (t) | cp_type_quals (r),
9909 complain | tf_ignore_bad_quals);
9912 /* Else we must be instantiating the typedef, so fall through. */
9916 && TREE_CODE (t) != TYPENAME_TYPE
9917 && TREE_CODE (t) != IDENTIFIER_NODE
9918 && TREE_CODE (t) != FUNCTION_TYPE
9919 && TREE_CODE (t) != METHOD_TYPE)
9920 type = tsubst (type, args, complain, in_decl);
9921 if (type == error_mark_node)
9922 return error_mark_node;
9924 switch (TREE_CODE (t))
9929 return tsubst_aggr_type (t, args, complain, in_decl,
9930 /*entering_scope=*/0);
9933 case IDENTIFIER_NODE:
9945 if (t == integer_type_node)
9948 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9949 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9953 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9955 max = tsubst_expr (omax, args, complain, in_decl,
9956 /*integral_constant_expression_p=*/false);
9958 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9960 if (TREE_CODE (max) == NOP_EXPR
9961 && TREE_SIDE_EFFECTS (omax)
9962 && !TREE_TYPE (max))
9963 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9965 max = fold_decl_constant_value (max);
9967 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9968 with TREE_SIDE_EFFECTS that indicates this is not an integral
9969 constant expression. */
9970 if (processing_template_decl
9971 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9973 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9974 TREE_SIDE_EFFECTS (max) = 1;
9977 if (TREE_CODE (max) != INTEGER_CST
9978 && !at_function_scope_p ()
9979 && !TREE_SIDE_EFFECTS (max)
9980 && !value_dependent_expression_p (max))
9982 if (complain & tf_error)
9983 error ("array bound is not an integer constant");
9984 return error_mark_node;
9989 Type deduction may fail for any of the following
9992 Attempting to create an array with a size that is
9993 zero or negative. */
9994 if (integer_zerop (max) && !(complain & tf_error))
9995 /* We must fail if performing argument deduction (as
9996 indicated by the state of complain), so that
9997 another substitution can be found. */
9998 return error_mark_node;
9999 else if (TREE_CODE (max) == INTEGER_CST
10000 && INT_CST_LT (max, integer_zero_node))
10002 if (complain & tf_error)
10003 error ("creating array with negative size (%qE)", max);
10005 return error_mark_node;
10008 return compute_array_index_type (NULL_TREE, max);
10011 case TEMPLATE_TYPE_PARM:
10012 case TEMPLATE_TEMPLATE_PARM:
10013 case BOUND_TEMPLATE_TEMPLATE_PARM:
10014 case TEMPLATE_PARM_INDEX:
10019 tree arg = NULL_TREE;
10023 gcc_assert (TREE_VEC_LENGTH (args) > 0);
10024 template_parm_level_and_index (t, &level, &idx);
10026 levels = TMPL_ARGS_DEPTH (args);
10027 if (level <= levels)
10029 arg = TMPL_ARG (args, level, idx);
10031 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
10032 /* See through ARGUMENT_PACK_SELECT arguments. */
10033 arg = ARGUMENT_PACK_SELECT_ARG (arg);
10036 if (arg == error_mark_node)
10037 return error_mark_node;
10038 else if (arg != NULL_TREE)
10040 if (ARGUMENT_PACK_P (arg))
10041 /* If ARG is an argument pack, we don't actually want to
10042 perform a substitution here, because substitutions
10043 for argument packs are only done
10044 element-by-element. We can get to this point when
10045 substituting the type of a non-type template
10046 parameter pack, when that type actually contains
10047 template parameter packs from an outer template, e.g.,
10049 template<typename... Types> struct A {
10050 template<Types... Values> struct B { };
10054 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
10057 gcc_assert (TYPE_P (arg));
10059 /* cv-quals from the template are discarded when
10060 substituting in a function or reference type. */
10061 if (TREE_CODE (arg) == FUNCTION_TYPE
10062 || TREE_CODE (arg) == METHOD_TYPE
10063 || TREE_CODE (arg) == REFERENCE_TYPE)
10064 quals = cp_type_quals (arg);
10066 quals = cp_type_quals (arg) | cp_type_quals (t);
10068 return cp_build_qualified_type_real
10069 (arg, quals, complain | tf_ignore_bad_quals);
10071 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
10073 /* We are processing a type constructed from a
10074 template template parameter. */
10075 tree argvec = tsubst (TYPE_TI_ARGS (t),
10076 args, complain, in_decl);
10077 if (argvec == error_mark_node)
10078 return error_mark_node;
10080 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10081 are resolving nested-types in the signature of a
10082 member function templates. Otherwise ARG is a
10083 TEMPLATE_DECL and is the real template to be
10085 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10086 arg = TYPE_NAME (arg);
10088 r = lookup_template_class (arg,
10090 DECL_CONTEXT (arg),
10091 /*entering_scope=*/0,
10093 return cp_build_qualified_type_real
10094 (r, TYPE_QUALS (t), complain);
10097 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10102 /* This can happen during the attempted tsubst'ing in
10103 unify. This means that we don't yet have any information
10104 about the template parameter in question. */
10107 /* If we get here, we must have been looking at a parm for a
10108 more deeply nested template. Make a new version of this
10109 template parameter, but with a lower level. */
10110 switch (TREE_CODE (t))
10112 case TEMPLATE_TYPE_PARM:
10113 case TEMPLATE_TEMPLATE_PARM:
10114 case BOUND_TEMPLATE_TEMPLATE_PARM:
10115 if (cp_type_quals (t))
10117 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10118 r = cp_build_qualified_type_real
10119 (r, cp_type_quals (t),
10120 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
10121 ? tf_ignore_bad_quals : 0));
10126 TEMPLATE_TYPE_PARM_INDEX (r)
10127 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10128 r, levels, args, complain);
10129 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10130 TYPE_MAIN_VARIANT (r) = r;
10131 TYPE_POINTER_TO (r) = NULL_TREE;
10132 TYPE_REFERENCE_TO (r) = NULL_TREE;
10134 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10135 /* We have reduced the level of the template
10136 template parameter, but not the levels of its
10137 template parameters, so canonical_type_parameter
10138 will not be able to find the canonical template
10139 template parameter for this level. Thus, we
10140 require structural equality checking to compare
10141 TEMPLATE_TEMPLATE_PARMs. */
10142 SET_TYPE_STRUCTURAL_EQUALITY (r);
10143 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10144 SET_TYPE_STRUCTURAL_EQUALITY (r);
10146 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10148 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
10150 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10151 complain, in_decl);
10152 if (argvec == error_mark_node)
10153 return error_mark_node;
10155 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10156 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10161 case TEMPLATE_PARM_INDEX:
10162 r = reduce_template_parm_level (t, type, levels, args, complain);
10166 gcc_unreachable ();
10174 tree purpose, value, chain;
10176 if (t == void_list_node)
10179 purpose = TREE_PURPOSE (t);
10182 purpose = tsubst (purpose, args, complain, in_decl);
10183 if (purpose == error_mark_node)
10184 return error_mark_node;
10186 value = TREE_VALUE (t);
10189 value = tsubst (value, args, complain, in_decl);
10190 if (value == error_mark_node)
10191 return error_mark_node;
10193 chain = TREE_CHAIN (t);
10194 if (chain && chain != void_type_node)
10196 chain = tsubst (chain, args, complain, in_decl);
10197 if (chain == error_mark_node)
10198 return error_mark_node;
10200 if (purpose == TREE_PURPOSE (t)
10201 && value == TREE_VALUE (t)
10202 && chain == TREE_CHAIN (t))
10204 return hash_tree_cons (purpose, value, chain);
10208 /* We should never be tsubsting a binfo. */
10209 gcc_unreachable ();
10212 /* A vector of template arguments. */
10213 gcc_assert (!type);
10214 return tsubst_template_args (t, args, complain, in_decl);
10217 case REFERENCE_TYPE:
10219 enum tree_code code;
10221 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10224 code = TREE_CODE (t);
10229 Type deduction may fail for any of the following
10232 -- Attempting to create a pointer to reference type.
10233 -- Attempting to create a reference to a reference type or
10234 a reference to void.
10236 Core issue 106 says that creating a reference to a reference
10237 during instantiation is no longer a cause for failure. We
10238 only enforce this check in strict C++98 mode. */
10239 if ((TREE_CODE (type) == REFERENCE_TYPE
10240 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10241 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10243 static location_t last_loc;
10245 /* We keep track of the last time we issued this error
10246 message to avoid spewing a ton of messages during a
10247 single bad template instantiation. */
10248 if (complain & tf_error
10249 && last_loc != input_location)
10251 if (TREE_CODE (type) == VOID_TYPE)
10252 error ("forming reference to void");
10253 else if (code == POINTER_TYPE)
10254 error ("forming pointer to reference type %qT", type);
10256 error ("forming reference to reference type %qT", type);
10257 last_loc = input_location;
10260 return error_mark_node;
10262 else if (code == POINTER_TYPE)
10264 r = build_pointer_type (type);
10265 if (TREE_CODE (type) == METHOD_TYPE)
10266 r = build_ptrmemfunc_type (r);
10268 else if (TREE_CODE (type) == REFERENCE_TYPE)
10269 /* In C++0x, during template argument substitution, when there is an
10270 attempt to create a reference to a reference type, reference
10271 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10273 "If a template-argument for a template-parameter T names a type
10274 that is a reference to a type A, an attempt to create the type
10275 'lvalue reference to cv T' creates the type 'lvalue reference to
10276 A,' while an attempt to create the type type rvalue reference to
10277 cv T' creates the type T"
10279 r = cp_build_reference_type
10281 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10283 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10284 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
10286 if (r != error_mark_node)
10287 /* Will this ever be needed for TYPE_..._TO values? */
10294 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10295 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10299 Type deduction may fail for any of the following
10302 -- Attempting to create "pointer to member of T" when T
10303 is not a class type. */
10304 if (complain & tf_error)
10305 error ("creating pointer to member of non-class type %qT", r);
10306 return error_mark_node;
10308 if (TREE_CODE (type) == REFERENCE_TYPE)
10310 if (complain & tf_error)
10311 error ("creating pointer to member reference type %qT", type);
10312 return error_mark_node;
10314 if (TREE_CODE (type) == VOID_TYPE)
10316 if (complain & tf_error)
10317 error ("creating pointer to member of type void");
10318 return error_mark_node;
10320 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10321 if (TREE_CODE (type) == FUNCTION_TYPE)
10323 /* The type of the implicit object parameter gets its
10324 cv-qualifiers from the FUNCTION_TYPE. */
10326 tree method_type = build_memfn_type (type, r, cp_type_quals (type));
10327 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10328 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10332 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10336 case FUNCTION_TYPE:
10341 fntype = tsubst_function_type (t, args, complain, in_decl);
10342 if (fntype == error_mark_node)
10343 return error_mark_node;
10345 /* Substitute the exception specification. */
10346 specs = tsubst_exception_specification (t, args, complain,
10348 if (specs == error_mark_node)
10349 return error_mark_node;
10351 fntype = build_exception_variant (fntype, specs);
10356 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10357 if (domain == error_mark_node)
10358 return error_mark_node;
10360 /* As an optimization, we avoid regenerating the array type if
10361 it will obviously be the same as T. */
10362 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10365 /* These checks should match the ones in grokdeclarator.
10369 The deduction may fail for any of the following reasons:
10371 -- Attempting to create an array with an element type that
10372 is void, a function type, or a reference type, or [DR337]
10373 an abstract class type. */
10374 if (TREE_CODE (type) == VOID_TYPE
10375 || TREE_CODE (type) == FUNCTION_TYPE
10376 || TREE_CODE (type) == REFERENCE_TYPE)
10378 if (complain & tf_error)
10379 error ("creating array of %qT", type);
10380 return error_mark_node;
10382 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10384 if (complain & tf_error)
10385 error ("creating array of %qT, which is an abstract class type",
10387 return error_mark_node;
10390 r = build_cplus_array_type (type, domain);
10392 if (TYPE_USER_ALIGN (t))
10394 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10395 TYPE_USER_ALIGN (r) = 1;
10404 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10405 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10407 if (e1 == error_mark_node || e2 == error_mark_node)
10408 return error_mark_node;
10410 return fold_build2_loc (input_location,
10411 TREE_CODE (t), TREE_TYPE (t), e1, e2);
10417 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10418 if (e == error_mark_node)
10419 return error_mark_node;
10421 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
10424 case TYPENAME_TYPE:
10426 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10427 in_decl, /*entering_scope=*/1);
10428 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10429 complain, in_decl);
10431 if (ctx == error_mark_node || f == error_mark_node)
10432 return error_mark_node;
10434 if (!MAYBE_CLASS_TYPE_P (ctx))
10436 if (complain & tf_error)
10437 error ("%qT is not a class, struct, or union type", ctx);
10438 return error_mark_node;
10440 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10442 /* Normally, make_typename_type does not require that the CTX
10443 have complete type in order to allow things like:
10445 template <class T> struct S { typename S<T>::X Y; };
10447 But, such constructs have already been resolved by this
10448 point, so here CTX really should have complete type, unless
10449 it's a partial instantiation. */
10450 if (!(complain & tf_no_class_instantiations))
10451 ctx = complete_type (ctx);
10452 if (!COMPLETE_TYPE_P (ctx))
10454 if (complain & tf_error)
10455 cxx_incomplete_type_error (NULL_TREE, ctx);
10456 return error_mark_node;
10460 f = make_typename_type (ctx, f, typename_type,
10461 (complain & tf_error) | tf_keep_type_decl);
10462 if (f == error_mark_node)
10464 if (TREE_CODE (f) == TYPE_DECL)
10466 complain |= tf_ignore_bad_quals;
10470 if (TREE_CODE (f) != TYPENAME_TYPE)
10472 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10473 error ("%qT resolves to %qT, which is not an enumeration type",
10475 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10476 error ("%qT resolves to %qT, which is is not a class type",
10480 return cp_build_qualified_type_real
10481 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10484 case UNBOUND_CLASS_TEMPLATE:
10486 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10487 in_decl, /*entering_scope=*/1);
10488 tree name = TYPE_IDENTIFIER (t);
10489 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10491 if (ctx == error_mark_node || name == error_mark_node)
10492 return error_mark_node;
10495 parm_list = tsubst_template_parms (parm_list, args, complain);
10496 return make_unbound_class_template (ctx, name, parm_list, complain);
10502 gcc_unreachable ();
10506 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10507 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10508 /*integral_constant_expression_p=*/false);
10509 if (e1 == error_mark_node || e2 == error_mark_node)
10510 return error_mark_node;
10512 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10517 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10518 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10519 if (e1 == error_mark_node || e2 == error_mark_node)
10520 return error_mark_node;
10522 return build_qualified_name (/*type=*/NULL_TREE,
10523 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10530 ++cp_unevaluated_operand;
10531 ++c_inhibit_evaluation_warnings;
10533 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10535 /*integral_constant_expression_p=*/false);
10537 --cp_unevaluated_operand;
10538 --c_inhibit_evaluation_warnings;
10540 type = finish_typeof (type);
10541 return cp_build_qualified_type_real (type,
10543 | cp_type_quals (type),
10547 case DECLTYPE_TYPE:
10551 ++cp_unevaluated_operand;
10552 ++c_inhibit_evaluation_warnings;
10554 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10556 /*integral_constant_expression_p=*/false);
10558 --cp_unevaluated_operand;
10559 --c_inhibit_evaluation_warnings;
10561 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10562 type = lambda_capture_field_type (type);
10563 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10564 type = lambda_return_type (type);
10566 type = finish_decltype_type
10567 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10568 return cp_build_qualified_type_real (type,
10570 | cp_type_quals (type),
10574 case TYPE_ARGUMENT_PACK:
10575 case NONTYPE_ARGUMENT_PACK:
10577 tree r = TYPE_P (t)
10578 ? cxx_make_type (TREE_CODE (t))
10579 : make_node (TREE_CODE (t));
10581 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10585 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10587 /* For template nontype argument packs, also substitute into
10589 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10590 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10597 sorry ("use of %qs in template",
10598 tree_code_name [(int) TREE_CODE (t)]);
10599 return error_mark_node;
10603 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10604 type of the expression on the left-hand side of the "." or "->"
10608 tsubst_baselink (tree baselink, tree object_type,
10609 tree args, tsubst_flags_t complain, tree in_decl)
10612 tree qualifying_scope;
10615 tree template_args = 0;
10616 bool template_id_p = false;
10618 /* A baselink indicates a function from a base class. Both the
10619 BASELINK_ACCESS_BINFO and the base class referenced may
10620 indicate bases of the template class, rather than the
10621 instantiated class. In addition, lookups that were not
10622 ambiguous before may be ambiguous now. Therefore, we perform
10623 the lookup again. */
10624 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10625 qualifying_scope = tsubst (qualifying_scope, args,
10626 complain, in_decl);
10627 fns = BASELINK_FUNCTIONS (baselink);
10628 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
10629 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10631 template_id_p = true;
10632 template_args = TREE_OPERAND (fns, 1);
10633 fns = TREE_OPERAND (fns, 0);
10635 template_args = tsubst_template_args (template_args, args,
10636 complain, in_decl);
10638 name = DECL_NAME (get_first_fn (fns));
10639 if (IDENTIFIER_TYPENAME_P (name))
10640 name = mangle_conv_op_name_for_type (optype);
10641 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10643 /* If lookup found a single function, mark it as used at this
10644 point. (If it lookup found multiple functions the one selected
10645 later by overload resolution will be marked as used at that
10647 if (BASELINK_P (baselink))
10648 fns = BASELINK_FUNCTIONS (baselink);
10649 if (!template_id_p && !really_overloaded_fn (fns))
10650 mark_used (OVL_CURRENT (fns));
10652 /* Add back the template arguments, if present. */
10653 if (BASELINK_P (baselink) && template_id_p)
10654 BASELINK_FUNCTIONS (baselink)
10655 = build_nt (TEMPLATE_ID_EXPR,
10656 BASELINK_FUNCTIONS (baselink),
10658 /* Update the conversion operator type. */
10659 BASELINK_OPTYPE (baselink) = optype;
10662 object_type = current_class_type;
10663 return adjust_result_of_qualified_name_lookup (baselink,
10668 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10669 true if the qualified-id will be a postfix-expression in-and-of
10670 itself; false if more of the postfix-expression follows the
10671 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10675 tsubst_qualified_id (tree qualified_id, tree args,
10676 tsubst_flags_t complain, tree in_decl,
10677 bool done, bool address_p)
10683 tree template_args;
10685 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10687 /* Figure out what name to look up. */
10688 name = TREE_OPERAND (qualified_id, 1);
10689 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10691 is_template = true;
10692 template_args = TREE_OPERAND (name, 1);
10694 template_args = tsubst_template_args (template_args, args,
10695 complain, in_decl);
10696 name = TREE_OPERAND (name, 0);
10700 is_template = false;
10701 template_args = NULL_TREE;
10704 /* Substitute into the qualifying scope. When there are no ARGS, we
10705 are just trying to simplify a non-dependent expression. In that
10706 case the qualifying scope may be dependent, and, in any case,
10707 substituting will not help. */
10708 scope = TREE_OPERAND (qualified_id, 0);
10711 scope = tsubst (scope, args, complain, in_decl);
10712 expr = tsubst_copy (name, args, complain, in_decl);
10717 if (dependent_scope_p (scope))
10718 return build_qualified_name (NULL_TREE, scope, expr,
10719 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10721 if (!BASELINK_P (name) && !DECL_P (expr))
10723 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10725 /* A BIT_NOT_EXPR is used to represent a destructor. */
10726 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10728 error ("qualifying type %qT does not match destructor name ~%qT",
10729 scope, TREE_OPERAND (expr, 0));
10730 expr = error_mark_node;
10733 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10734 /*is_type_p=*/0, false);
10737 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10738 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10739 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10741 if (complain & tf_error)
10743 error ("dependent-name %qE is parsed as a non-type, but "
10744 "instantiation yields a type", qualified_id);
10745 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10747 return error_mark_node;
10753 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10755 /* Remember that there was a reference to this entity. */
10759 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10761 if (complain & tf_error)
10762 qualified_name_lookup_error (scope,
10763 TREE_OPERAND (qualified_id, 1),
10764 expr, input_location);
10765 return error_mark_node;
10769 expr = lookup_template_function (expr, template_args);
10771 if (expr == error_mark_node && complain & tf_error)
10772 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10773 expr, input_location);
10774 else if (TYPE_P (scope))
10776 expr = (adjust_result_of_qualified_name_lookup
10777 (expr, scope, current_class_type));
10778 expr = (finish_qualified_id_expr
10779 (scope, expr, done, address_p,
10780 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10781 /*template_arg_p=*/false));
10784 /* Expressions do not generally have reference type. */
10785 if (TREE_CODE (expr) != SCOPE_REF
10786 /* However, if we're about to form a pointer-to-member, we just
10787 want the referenced member referenced. */
10788 && TREE_CODE (expr) != OFFSET_REF)
10789 expr = convert_from_reference (expr);
10794 /* Like tsubst, but deals with expressions. This function just replaces
10795 template parms; to finish processing the resultant expression, use
10799 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10801 enum tree_code code;
10804 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10807 code = TREE_CODE (t);
10812 r = retrieve_local_specialization (t);
10817 /* This can happen for a parameter name used later in a function
10818 declaration (such as in a late-specified return type). Just
10819 make a dummy decl, since it's only used for its type. */
10820 gcc_assert (cp_unevaluated_operand != 0);
10821 /* We copy T because want to tsubst the PARM_DECL only,
10822 not the following PARM_DECLs that are chained to T. */
10824 r = tsubst_decl (c, args, complain);
10825 /* Give it the template pattern as its context; its true context
10826 hasn't been instantiated yet and this is good enough for
10828 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10831 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10832 r = ARGUMENT_PACK_SELECT_ARG (r);
10841 if (DECL_TEMPLATE_PARM_P (t))
10842 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10843 /* There is no need to substitute into namespace-scope
10845 if (DECL_NAMESPACE_SCOPE_P (t))
10847 /* If ARGS is NULL, then T is known to be non-dependent. */
10848 if (args == NULL_TREE)
10849 return integral_constant_value (t);
10851 /* Unfortunately, we cannot just call lookup_name here.
10854 template <int I> int f() {
10856 struct S { void g() { E e = a; } };
10859 When we instantiate f<7>::S::g(), say, lookup_name is not
10860 clever enough to find f<7>::a. */
10862 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10863 /*entering_scope=*/0);
10865 for (v = TYPE_VALUES (enum_type);
10867 v = TREE_CHAIN (v))
10868 if (TREE_PURPOSE (v) == DECL_NAME (t))
10869 return TREE_VALUE (v);
10871 /* We didn't find the name. That should never happen; if
10872 name-lookup found it during preliminary parsing, we
10873 should find it again here during instantiation. */
10874 gcc_unreachable ();
10879 if (DECL_CONTEXT (t))
10883 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10884 /*entering_scope=*/1);
10885 if (ctx != DECL_CONTEXT (t))
10887 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10890 if (complain & tf_error)
10891 error ("using invalid field %qD", t);
10892 return error_mark_node;
10901 case FUNCTION_DECL:
10902 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10903 || local_variable_p (t))
10904 t = tsubst (t, args, complain, in_decl);
10909 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10911 case TEMPLATE_DECL:
10912 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10913 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10914 args, complain, in_decl);
10915 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10916 return tsubst (t, args, complain, in_decl);
10917 else if (DECL_CLASS_SCOPE_P (t)
10918 && uses_template_parms (DECL_CONTEXT (t)))
10920 /* Template template argument like the following example need
10923 template <template <class> class TT> struct C {};
10924 template <class T> struct D {
10925 template <class U> struct E {};
10930 We are processing the template argument `E' in #1 for
10931 the template instantiation #2. Originally, `E' is a
10932 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10933 have to substitute this with one having context `D<int>'. */
10935 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10936 return lookup_field (context, DECL_NAME(t), 0, false);
10939 /* Ordinary template template argument. */
10943 case REINTERPRET_CAST_EXPR:
10944 case CONST_CAST_EXPR:
10945 case STATIC_CAST_EXPR:
10946 case DYNAMIC_CAST_EXPR:
10949 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10950 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10953 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10955 /* We only want to compute the number of arguments. */
10956 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10957 complain, in_decl);
10960 if (TREE_CODE (expanded) == TREE_VEC)
10961 len = TREE_VEC_LENGTH (expanded);
10963 if (expanded == error_mark_node)
10964 return error_mark_node;
10965 else if (PACK_EXPANSION_P (expanded)
10966 || (TREE_CODE (expanded) == TREE_VEC
10968 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10970 if (TREE_CODE (expanded) == TREE_VEC)
10971 expanded = TREE_VEC_ELT (expanded, len - 1);
10973 if (TYPE_P (expanded))
10974 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10975 complain & tf_error);
10977 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10978 complain & tf_error);
10981 return build_int_cst (size_type_node, len);
10987 case TRUTH_NOT_EXPR:
10990 case UNARY_PLUS_EXPR: /* Unary + */
10995 case REALPART_EXPR:
10996 case IMAGPART_EXPR:
10998 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10999 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
11001 case COMPONENT_REF:
11006 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
11007 name = TREE_OPERAND (t, 1);
11008 if (TREE_CODE (name) == BIT_NOT_EXPR)
11010 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11011 complain, in_decl);
11012 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11014 else if (TREE_CODE (name) == SCOPE_REF
11015 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
11017 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
11018 complain, in_decl);
11019 name = TREE_OPERAND (name, 1);
11020 name = tsubst_copy (TREE_OPERAND (name, 0), args,
11021 complain, in_decl);
11022 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
11023 name = build_qualified_name (/*type=*/NULL_TREE,
11025 /*template_p=*/false);
11027 else if (TREE_CODE (name) == BASELINK)
11028 name = tsubst_baselink (name,
11029 non_reference (TREE_TYPE (object)),
11033 name = tsubst_copy (name, args, complain, in_decl);
11034 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
11040 case TRUNC_DIV_EXPR:
11041 case CEIL_DIV_EXPR:
11042 case FLOOR_DIV_EXPR:
11043 case ROUND_DIV_EXPR:
11044 case EXACT_DIV_EXPR:
11048 case TRUNC_MOD_EXPR:
11049 case FLOOR_MOD_EXPR:
11050 case TRUTH_ANDIF_EXPR:
11051 case TRUTH_ORIF_EXPR:
11052 case TRUTH_AND_EXPR:
11053 case TRUTH_OR_EXPR:
11066 case COMPOUND_EXPR:
11069 case PREDECREMENT_EXPR:
11070 case PREINCREMENT_EXPR:
11071 case POSTDECREMENT_EXPR:
11072 case POSTINCREMENT_EXPR:
11074 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11075 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11078 return build_qualified_name (/*type=*/NULL_TREE,
11079 tsubst_copy (TREE_OPERAND (t, 0),
11080 args, complain, in_decl),
11081 tsubst_copy (TREE_OPERAND (t, 1),
11082 args, complain, in_decl),
11083 QUALIFIED_NAME_IS_TEMPLATE (t));
11088 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11089 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11090 NULL_TREE, NULL_TREE);
11094 int n = VL_EXP_OPERAND_LENGTH (t);
11095 tree result = build_vl_exp (CALL_EXPR, n);
11097 for (i = 0; i < n; i++)
11098 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11099 complain, in_decl);
11105 case PSEUDO_DTOR_EXPR:
11108 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11109 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11110 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11111 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11118 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11119 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11120 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11121 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11128 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11129 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11130 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11131 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11135 case TEMPLATE_ID_EXPR:
11137 /* Substituted template arguments */
11138 tree fn = TREE_OPERAND (t, 0);
11139 tree targs = TREE_OPERAND (t, 1);
11141 fn = tsubst_copy (fn, args, complain, in_decl);
11143 targs = tsubst_template_args (targs, args, complain, in_decl);
11145 return lookup_template_function (fn, targs);
11150 tree purpose, value, chain;
11152 if (t == void_list_node)
11155 purpose = TREE_PURPOSE (t);
11157 purpose = tsubst_copy (purpose, args, complain, in_decl);
11158 value = TREE_VALUE (t);
11160 value = tsubst_copy (value, args, complain, in_decl);
11161 chain = TREE_CHAIN (t);
11162 if (chain && chain != void_type_node)
11163 chain = tsubst_copy (chain, args, complain, in_decl);
11164 if (purpose == TREE_PURPOSE (t)
11165 && value == TREE_VALUE (t)
11166 && chain == TREE_CHAIN (t))
11168 return tree_cons (purpose, value, chain);
11173 case ENUMERAL_TYPE:
11175 case TEMPLATE_TYPE_PARM:
11176 case TEMPLATE_TEMPLATE_PARM:
11177 case BOUND_TEMPLATE_TEMPLATE_PARM:
11178 case TEMPLATE_PARM_INDEX:
11180 case REFERENCE_TYPE:
11182 case FUNCTION_TYPE:
11185 case TYPENAME_TYPE:
11186 case UNBOUND_CLASS_TEMPLATE:
11188 case DECLTYPE_TYPE:
11190 return tsubst (t, args, complain, in_decl);
11192 case IDENTIFIER_NODE:
11193 if (IDENTIFIER_TYPENAME_P (t))
11195 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11196 return mangle_conv_op_name_for_type (new_type);
11202 /* This is handled by tsubst_copy_and_build. */
11203 gcc_unreachable ();
11206 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11208 tsubst (TREE_TYPE (t), args, complain, in_decl));
11210 case CLEANUP_POINT_EXPR:
11211 /* We shouldn't have built any of these during initial template
11212 generation. Instead, they should be built during instantiation
11213 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11214 gcc_unreachable ();
11217 mark_used (TREE_OPERAND (t, 1));
11220 case EXPR_PACK_EXPANSION:
11221 error ("invalid use of pack expansion expression");
11222 return error_mark_node;
11224 case NONTYPE_ARGUMENT_PACK:
11225 error ("use %<...%> to expand argument pack");
11226 return error_mark_node;
11233 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11236 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11239 tree new_clauses = NULL, nc, oc;
11241 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11243 nc = copy_node (oc);
11244 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11247 switch (OMP_CLAUSE_CODE (nc))
11249 case OMP_CLAUSE_LASTPRIVATE:
11250 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11252 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11253 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11254 in_decl, /*integral_constant_expression_p=*/false);
11255 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11256 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11259 case OMP_CLAUSE_PRIVATE:
11260 case OMP_CLAUSE_SHARED:
11261 case OMP_CLAUSE_FIRSTPRIVATE:
11262 case OMP_CLAUSE_REDUCTION:
11263 case OMP_CLAUSE_COPYIN:
11264 case OMP_CLAUSE_COPYPRIVATE:
11265 case OMP_CLAUSE_IF:
11266 case OMP_CLAUSE_NUM_THREADS:
11267 case OMP_CLAUSE_SCHEDULE:
11268 case OMP_CLAUSE_COLLAPSE:
11269 OMP_CLAUSE_OPERAND (nc, 0)
11270 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11271 in_decl, /*integral_constant_expression_p=*/false);
11273 case OMP_CLAUSE_NOWAIT:
11274 case OMP_CLAUSE_ORDERED:
11275 case OMP_CLAUSE_DEFAULT:
11276 case OMP_CLAUSE_UNTIED:
11279 gcc_unreachable ();
11283 return finish_omp_clauses (nreverse (new_clauses));
11286 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11289 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11292 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11294 tree purpose, value, chain;
11299 if (TREE_CODE (t) != TREE_LIST)
11300 return tsubst_copy_and_build (t, args, complain, in_decl,
11301 /*function_p=*/false,
11302 /*integral_constant_expression_p=*/false);
11304 if (t == void_list_node)
11307 purpose = TREE_PURPOSE (t);
11309 purpose = RECUR (purpose);
11310 value = TREE_VALUE (t);
11311 if (value && TREE_CODE (value) != LABEL_DECL)
11312 value = RECUR (value);
11313 chain = TREE_CHAIN (t);
11314 if (chain && chain != void_type_node)
11315 chain = RECUR (chain);
11316 return tree_cons (purpose, value, chain);
11320 /* Substitute one OMP_FOR iterator. */
11323 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11324 tree condv, tree incrv, tree *clauses,
11325 tree args, tsubst_flags_t complain, tree in_decl,
11326 bool integral_constant_expression_p)
11328 #define RECUR(NODE) \
11329 tsubst_expr ((NODE), args, complain, in_decl, \
11330 integral_constant_expression_p)
11331 tree decl, init, cond, incr, auto_node;
11333 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11334 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11335 decl = RECUR (TREE_OPERAND (init, 0));
11336 init = TREE_OPERAND (init, 1);
11337 auto_node = type_uses_auto (TREE_TYPE (decl));
11338 if (auto_node && init)
11340 tree init_expr = init;
11341 if (TREE_CODE (init_expr) == DECL_EXPR)
11342 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11343 init_expr = RECUR (init_expr);
11345 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11347 gcc_assert (!type_dependent_expression_p (decl));
11349 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11351 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11352 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11353 if (TREE_CODE (incr) == MODIFY_EXPR)
11354 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11355 RECUR (TREE_OPERAND (incr, 1)),
11358 incr = RECUR (incr);
11359 TREE_VEC_ELT (declv, i) = decl;
11360 TREE_VEC_ELT (initv, i) = init;
11361 TREE_VEC_ELT (condv, i) = cond;
11362 TREE_VEC_ELT (incrv, i) = incr;
11366 if (init && TREE_CODE (init) != DECL_EXPR)
11369 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11371 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11372 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11373 && OMP_CLAUSE_DECL (c) == decl)
11375 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11376 && OMP_CLAUSE_DECL (c) == decl)
11377 error ("iteration variable %qD should not be firstprivate", decl);
11378 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11379 && OMP_CLAUSE_DECL (c) == decl)
11380 error ("iteration variable %qD should not be reduction", decl);
11384 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11385 OMP_CLAUSE_DECL (c) = decl;
11386 c = finish_omp_clauses (c);
11389 OMP_CLAUSE_CHAIN (c) = *clauses;
11394 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11395 if (COMPARISON_CLASS_P (cond))
11396 cond = build2 (TREE_CODE (cond), boolean_type_node,
11397 RECUR (TREE_OPERAND (cond, 0)),
11398 RECUR (TREE_OPERAND (cond, 1)));
11400 cond = RECUR (cond);
11401 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11402 switch (TREE_CODE (incr))
11404 case PREINCREMENT_EXPR:
11405 case PREDECREMENT_EXPR:
11406 case POSTINCREMENT_EXPR:
11407 case POSTDECREMENT_EXPR:
11408 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11409 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11412 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11413 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11415 tree rhs = TREE_OPERAND (incr, 1);
11416 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11417 RECUR (TREE_OPERAND (incr, 0)),
11418 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11419 RECUR (TREE_OPERAND (rhs, 0)),
11420 RECUR (TREE_OPERAND (rhs, 1))));
11423 incr = RECUR (incr);
11426 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11427 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11429 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11430 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11431 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11432 TREE_TYPE (decl), lhs,
11433 RECUR (TREE_OPERAND (incr, 2))));
11435 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11436 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11437 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11439 tree rhs = TREE_OPERAND (incr, 2);
11440 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11441 RECUR (TREE_OPERAND (incr, 0)),
11442 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11443 RECUR (TREE_OPERAND (rhs, 0)),
11444 RECUR (TREE_OPERAND (rhs, 1))));
11447 incr = RECUR (incr);
11450 incr = RECUR (incr);
11454 TREE_VEC_ELT (declv, i) = decl;
11455 TREE_VEC_ELT (initv, i) = init;
11456 TREE_VEC_ELT (condv, i) = cond;
11457 TREE_VEC_ELT (incrv, i) = incr;
11461 /* Like tsubst_copy for expressions, etc. but also does semantic
11465 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11466 bool integral_constant_expression_p)
11468 #define RECUR(NODE) \
11469 tsubst_expr ((NODE), args, complain, in_decl, \
11470 integral_constant_expression_p)
11474 if (t == NULL_TREE || t == error_mark_node)
11477 if (EXPR_HAS_LOCATION (t))
11478 input_location = EXPR_LOCATION (t);
11479 if (STATEMENT_CODE_P (TREE_CODE (t)))
11480 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11482 switch (TREE_CODE (t))
11484 case STATEMENT_LIST:
11486 tree_stmt_iterator i;
11487 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11488 RECUR (tsi_stmt (i));
11492 case CTOR_INITIALIZER:
11493 finish_mem_initializers (tsubst_initializer_list
11494 (TREE_OPERAND (t, 0), args));
11498 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11502 tmp = RECUR (EXPR_STMT_EXPR (t));
11503 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11504 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11506 finish_expr_stmt (tmp);
11510 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11518 decl = DECL_EXPR_DECL (t);
11519 if (TREE_CODE (decl) == LABEL_DECL)
11520 finish_label_decl (DECL_NAME (decl));
11521 else if (TREE_CODE (decl) == USING_DECL)
11523 tree scope = USING_DECL_SCOPE (decl);
11524 tree name = DECL_NAME (decl);
11527 scope = RECUR (scope);
11528 decl = lookup_qualified_name (scope, name,
11529 /*is_type_p=*/false,
11530 /*complain=*/false);
11531 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11532 qualified_name_lookup_error (scope, name, decl, input_location);
11534 do_local_using_decl (decl, scope, name);
11538 init = DECL_INITIAL (decl);
11539 decl = tsubst (decl, args, complain, in_decl);
11540 if (decl != error_mark_node)
11542 /* By marking the declaration as instantiated, we avoid
11543 trying to instantiate it. Since instantiate_decl can't
11544 handle local variables, and since we've already done
11545 all that needs to be done, that's the right thing to
11547 if (TREE_CODE (decl) == VAR_DECL)
11548 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11549 if (TREE_CODE (decl) == VAR_DECL
11550 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11551 /* Anonymous aggregates are a special case. */
11552 finish_anon_union (decl);
11555 maybe_push_decl (decl);
11556 if (TREE_CODE (decl) == VAR_DECL
11557 && DECL_PRETTY_FUNCTION_P (decl))
11559 /* For __PRETTY_FUNCTION__ we have to adjust the
11561 const char *const name
11562 = cxx_printable_name (current_function_decl, 2);
11563 init = cp_fname_init (name, &TREE_TYPE (decl));
11567 tree t = RECUR (init);
11570 /* If we had an initializer but it
11571 instantiated to nothing,
11572 value-initialize the object. This will
11573 only occur when the initializer was a
11574 pack expansion where the parameter packs
11575 used in that expansion were of length
11577 init = build_value_init (TREE_TYPE (decl));
11582 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11587 /* A DECL_EXPR can also be used as an expression, in the condition
11588 clause of an if/for/while construct. */
11593 stmt = begin_for_stmt ();
11594 RECUR (FOR_INIT_STMT (t));
11595 finish_for_init_stmt (stmt);
11596 tmp = RECUR (FOR_COND (t));
11597 finish_for_cond (tmp, stmt);
11598 tmp = RECUR (FOR_EXPR (t));
11599 finish_for_expr (tmp, stmt);
11600 RECUR (FOR_BODY (t));
11601 finish_for_stmt (stmt);
11605 stmt = begin_while_stmt ();
11606 tmp = RECUR (WHILE_COND (t));
11607 finish_while_stmt_cond (tmp, stmt);
11608 RECUR (WHILE_BODY (t));
11609 finish_while_stmt (stmt);
11613 stmt = begin_do_stmt ();
11614 RECUR (DO_BODY (t));
11615 finish_do_body (stmt);
11616 tmp = RECUR (DO_COND (t));
11617 finish_do_stmt (tmp, stmt);
11621 stmt = begin_if_stmt ();
11622 tmp = RECUR (IF_COND (t));
11623 finish_if_stmt_cond (tmp, stmt);
11624 RECUR (THEN_CLAUSE (t));
11625 finish_then_clause (stmt);
11627 if (ELSE_CLAUSE (t))
11629 begin_else_clause (stmt);
11630 RECUR (ELSE_CLAUSE (t));
11631 finish_else_clause (stmt);
11634 finish_if_stmt (stmt);
11638 if (BIND_EXPR_BODY_BLOCK (t))
11639 stmt = begin_function_body ();
11641 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11642 ? BCS_TRY_BLOCK : 0);
11644 RECUR (BIND_EXPR_BODY (t));
11646 if (BIND_EXPR_BODY_BLOCK (t))
11647 finish_function_body (stmt);
11649 finish_compound_stmt (stmt);
11653 finish_break_stmt ();
11656 case CONTINUE_STMT:
11657 finish_continue_stmt ();
11661 stmt = begin_switch_stmt ();
11662 tmp = RECUR (SWITCH_STMT_COND (t));
11663 finish_switch_cond (tmp, stmt);
11664 RECUR (SWITCH_STMT_BODY (t));
11665 finish_switch_stmt (stmt);
11668 case CASE_LABEL_EXPR:
11669 finish_case_label (EXPR_LOCATION (t),
11670 RECUR (CASE_LOW (t)),
11671 RECUR (CASE_HIGH (t)));
11676 tree decl = LABEL_EXPR_LABEL (t);
11679 label = finish_label_stmt (DECL_NAME (decl));
11680 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11681 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11686 tmp = GOTO_DESTINATION (t);
11687 if (TREE_CODE (tmp) != LABEL_DECL)
11688 /* Computed goto's must be tsubst'd into. On the other hand,
11689 non-computed gotos must not be; the identifier in question
11690 will have no binding. */
11693 tmp = DECL_NAME (tmp);
11694 finish_goto_stmt (tmp);
11698 tmp = finish_asm_stmt
11699 (ASM_VOLATILE_P (t),
11700 RECUR (ASM_STRING (t)),
11701 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11702 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11703 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11704 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11706 tree asm_expr = tmp;
11707 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11708 asm_expr = TREE_OPERAND (asm_expr, 0);
11709 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11716 stmt = begin_try_block ();
11717 RECUR (TRY_STMTS (t));
11718 finish_cleanup_try_block (stmt);
11719 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11723 tree compound_stmt = NULL_TREE;
11725 if (FN_TRY_BLOCK_P (t))
11726 stmt = begin_function_try_block (&compound_stmt);
11728 stmt = begin_try_block ();
11730 RECUR (TRY_STMTS (t));
11732 if (FN_TRY_BLOCK_P (t))
11733 finish_function_try_block (stmt);
11735 finish_try_block (stmt);
11737 RECUR (TRY_HANDLERS (t));
11738 if (FN_TRY_BLOCK_P (t))
11739 finish_function_handler_sequence (stmt, compound_stmt);
11741 finish_handler_sequence (stmt);
11747 tree decl = HANDLER_PARMS (t);
11751 decl = tsubst (decl, args, complain, in_decl);
11752 /* Prevent instantiate_decl from trying to instantiate
11753 this variable. We've already done all that needs to be
11755 if (decl != error_mark_node)
11756 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11758 stmt = begin_handler ();
11759 finish_handler_parms (decl, stmt);
11760 RECUR (HANDLER_BODY (t));
11761 finish_handler (stmt);
11766 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11769 case STATIC_ASSERT:
11772 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11775 /*integral_constant_expression_p=*/true);
11776 finish_static_assert (condition,
11777 STATIC_ASSERT_MESSAGE (t),
11778 STATIC_ASSERT_SOURCE_LOCATION (t),
11779 /*member_p=*/false);
11784 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11785 args, complain, in_decl);
11786 stmt = begin_omp_parallel ();
11787 RECUR (OMP_PARALLEL_BODY (t));
11788 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11789 = OMP_PARALLEL_COMBINED (t);
11793 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11794 args, complain, in_decl);
11795 stmt = begin_omp_task ();
11796 RECUR (OMP_TASK_BODY (t));
11797 finish_omp_task (tmp, stmt);
11802 tree clauses, body, pre_body;
11803 tree declv, initv, condv, incrv;
11806 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11807 args, complain, in_decl);
11808 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11809 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11810 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11811 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11813 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11814 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11815 &clauses, args, complain, in_decl,
11816 integral_constant_expression_p);
11818 stmt = begin_omp_structured_block ();
11820 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11821 if (TREE_VEC_ELT (initv, i) == NULL
11822 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11823 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11824 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11826 tree init = RECUR (TREE_VEC_ELT (initv, i));
11827 gcc_assert (init == TREE_VEC_ELT (declv, i));
11828 TREE_VEC_ELT (initv, i) = NULL_TREE;
11832 tree decl_expr = TREE_VEC_ELT (initv, i);
11833 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11834 gcc_assert (init != NULL);
11835 TREE_VEC_ELT (initv, i) = RECUR (init);
11836 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11838 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11841 pre_body = push_stmt_list ();
11842 RECUR (OMP_FOR_PRE_BODY (t));
11843 pre_body = pop_stmt_list (pre_body);
11845 body = push_stmt_list ();
11846 RECUR (OMP_FOR_BODY (t));
11847 body = pop_stmt_list (body);
11849 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11850 body, pre_body, clauses);
11852 add_stmt (finish_omp_structured_block (stmt));
11858 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11859 stmt = push_stmt_list ();
11860 RECUR (OMP_BODY (t));
11861 stmt = pop_stmt_list (stmt);
11864 OMP_BODY (t) = stmt;
11865 OMP_CLAUSES (t) = tmp;
11873 stmt = push_stmt_list ();
11874 RECUR (OMP_BODY (t));
11875 stmt = pop_stmt_list (stmt);
11878 OMP_BODY (t) = stmt;
11883 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11885 tree op1 = TREE_OPERAND (t, 1);
11886 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11887 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11888 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11892 case EXPR_PACK_EXPANSION:
11893 error ("invalid use of pack expansion expression");
11894 return error_mark_node;
11896 case NONTYPE_ARGUMENT_PACK:
11897 error ("use %<...%> to expand argument pack");
11898 return error_mark_node;
11901 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11903 return tsubst_copy_and_build (t, args, complain, in_decl,
11904 /*function_p=*/false,
11905 integral_constant_expression_p);
11912 /* T is a postfix-expression that is not being used in a function
11913 call. Return the substituted version of T. */
11916 tsubst_non_call_postfix_expression (tree t, tree args,
11917 tsubst_flags_t complain,
11920 if (TREE_CODE (t) == SCOPE_REF)
11921 t = tsubst_qualified_id (t, args, complain, in_decl,
11922 /*done=*/false, /*address_p=*/false);
11924 t = tsubst_copy_and_build (t, args, complain, in_decl,
11925 /*function_p=*/false,
11926 /*integral_constant_expression_p=*/false);
11931 /* Like tsubst but deals with expressions and performs semantic
11932 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11935 tsubst_copy_and_build (tree t,
11937 tsubst_flags_t complain,
11940 bool integral_constant_expression_p)
11942 #define RECUR(NODE) \
11943 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11944 /*function_p=*/false, \
11945 integral_constant_expression_p)
11949 if (t == NULL_TREE || t == error_mark_node)
11952 switch (TREE_CODE (t))
11956 /* Fall through. */
11957 case IDENTIFIER_NODE:
11961 bool non_integral_constant_expression_p;
11962 const char *error_msg;
11964 if (IDENTIFIER_TYPENAME_P (t))
11966 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11967 t = mangle_conv_op_name_for_type (new_type);
11970 /* Look up the name. */
11971 decl = lookup_name (t);
11973 /* By convention, expressions use ERROR_MARK_NODE to indicate
11974 failure, not NULL_TREE. */
11975 if (decl == NULL_TREE)
11976 decl = error_mark_node;
11978 decl = finish_id_expression (t, decl, NULL_TREE,
11980 integral_constant_expression_p,
11981 /*allow_non_integral_constant_expression_p=*/false,
11982 &non_integral_constant_expression_p,
11983 /*template_p=*/false,
11985 /*address_p=*/false,
11986 /*template_arg_p=*/false,
11991 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11992 decl = unqualified_name_lookup_error (decl);
11996 case TEMPLATE_ID_EXPR:
11999 tree templ = RECUR (TREE_OPERAND (t, 0));
12000 tree targs = TREE_OPERAND (t, 1);
12003 targs = tsubst_template_args (targs, args, complain, in_decl);
12005 if (TREE_CODE (templ) == COMPONENT_REF)
12007 object = TREE_OPERAND (templ, 0);
12008 templ = TREE_OPERAND (templ, 1);
12011 object = NULL_TREE;
12012 templ = lookup_template_function (templ, targs);
12015 return build3 (COMPONENT_REF, TREE_TYPE (templ),
12016 object, templ, NULL_TREE);
12018 return baselink_for_fns (templ);
12023 tree r = RECUR (TREE_OPERAND (t, 0));
12025 if (REFERENCE_REF_P (t))
12027 /* A type conversion to reference type will be enclosed in
12028 such an indirect ref, but the substitution of the cast
12029 will have also added such an indirect ref. */
12030 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
12031 r = convert_from_reference (r);
12034 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
12040 (tsubst (TREE_TYPE (t), args, complain, in_decl),
12041 RECUR (TREE_OPERAND (t, 0)));
12044 case REINTERPRET_CAST_EXPR:
12045 case CONST_CAST_EXPR:
12046 case DYNAMIC_CAST_EXPR:
12047 case STATIC_CAST_EXPR:
12052 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12053 if (integral_constant_expression_p
12054 && !cast_valid_in_integral_constant_expression_p (type))
12056 if (complain & tf_error)
12057 error ("a cast to a type other than an integral or "
12058 "enumeration type cannot appear in a constant-expression");
12059 return error_mark_node;
12062 op = RECUR (TREE_OPERAND (t, 0));
12064 switch (TREE_CODE (t))
12067 return build_functional_cast (type, op, complain);
12068 case REINTERPRET_CAST_EXPR:
12069 return build_reinterpret_cast (type, op, complain);
12070 case CONST_CAST_EXPR:
12071 return build_const_cast (type, op, complain);
12072 case DYNAMIC_CAST_EXPR:
12073 return build_dynamic_cast (type, op, complain);
12074 case STATIC_CAST_EXPR:
12075 return build_static_cast (type, op, complain);
12077 gcc_unreachable ();
12081 case POSTDECREMENT_EXPR:
12082 case POSTINCREMENT_EXPR:
12083 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12084 args, complain, in_decl);
12085 return build_x_unary_op (TREE_CODE (t), op1, complain);
12087 case PREDECREMENT_EXPR:
12088 case PREINCREMENT_EXPR:
12092 case TRUTH_NOT_EXPR:
12093 case UNARY_PLUS_EXPR: /* Unary + */
12094 case REALPART_EXPR:
12095 case IMAGPART_EXPR:
12096 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12100 op1 = TREE_OPERAND (t, 0);
12101 if (TREE_CODE (op1) == SCOPE_REF)
12102 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12103 /*done=*/true, /*address_p=*/true);
12105 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12107 if (TREE_CODE (op1) == LABEL_DECL)
12108 return finish_label_address_expr (DECL_NAME (op1),
12109 EXPR_LOCATION (op1));
12110 return build_x_unary_op (ADDR_EXPR, op1, complain);
12115 case TRUNC_DIV_EXPR:
12116 case CEIL_DIV_EXPR:
12117 case FLOOR_DIV_EXPR:
12118 case ROUND_DIV_EXPR:
12119 case EXACT_DIV_EXPR:
12123 case TRUNC_MOD_EXPR:
12124 case FLOOR_MOD_EXPR:
12125 case TRUTH_ANDIF_EXPR:
12126 case TRUTH_ORIF_EXPR:
12127 case TRUTH_AND_EXPR:
12128 case TRUTH_OR_EXPR:
12143 return build_x_binary_op
12145 RECUR (TREE_OPERAND (t, 0)),
12146 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12148 : TREE_CODE (TREE_OPERAND (t, 0))),
12149 RECUR (TREE_OPERAND (t, 1)),
12150 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12152 : TREE_CODE (TREE_OPERAND (t, 1))),
12153 /*overloaded_p=*/NULL,
12157 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12158 /*address_p=*/false);
12160 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12161 args, complain, in_decl);
12162 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12165 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12166 return tsubst_copy (t, args, complain, in_decl);
12170 op1 = TREE_OPERAND (t, 0);
12173 /* When there are no ARGS, we are trying to evaluate a
12174 non-dependent expression from the parser. Trying to do
12175 the substitutions may not work. */
12177 op1 = TREE_TYPE (op1);
12181 ++cp_unevaluated_operand;
12182 ++c_inhibit_evaluation_warnings;
12183 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12184 /*function_p=*/false,
12185 /*integral_constant_expression_p=*/false);
12186 --cp_unevaluated_operand;
12187 --c_inhibit_evaluation_warnings;
12190 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12191 complain & tf_error);
12193 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12194 complain & tf_error);
12198 tree r = build_x_modify_expr
12199 (RECUR (TREE_OPERAND (t, 0)),
12200 TREE_CODE (TREE_OPERAND (t, 1)),
12201 RECUR (TREE_OPERAND (t, 2)),
12203 /* TREE_NO_WARNING must be set if either the expression was
12204 parenthesized or it uses an operator such as >>= rather
12205 than plain assignment. In the former case, it was already
12206 set and must be copied. In the latter case,
12207 build_x_modify_expr sets it and it must not be reset
12209 if (TREE_NO_WARNING (t))
12210 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12215 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12216 args, complain, in_decl);
12217 /* Remember that there was a reference to this entity. */
12220 return build_x_arrow (op1);
12224 tree placement = RECUR (TREE_OPERAND (t, 0));
12225 tree init = RECUR (TREE_OPERAND (t, 3));
12226 VEC(tree,gc) *placement_vec;
12227 VEC(tree,gc) *init_vec;
12230 if (placement == NULL_TREE)
12231 placement_vec = NULL;
12234 placement_vec = make_tree_vector ();
12235 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12236 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12239 /* If there was an initializer in the original tree, but it
12240 instantiated to an empty list, then we should pass a
12241 non-NULL empty vector to tell build_new that it was an
12242 empty initializer() rather than no initializer. This can
12243 only happen when the initializer is a pack expansion whose
12244 parameter packs are of length zero. */
12245 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12249 init_vec = make_tree_vector ();
12250 if (init == void_zero_node)
12251 gcc_assert (init_vec != NULL);
12254 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12255 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12259 ret = build_new (&placement_vec,
12260 RECUR (TREE_OPERAND (t, 1)),
12261 RECUR (TREE_OPERAND (t, 2)),
12263 NEW_EXPR_USE_GLOBAL (t),
12266 if (placement_vec != NULL)
12267 release_tree_vector (placement_vec);
12268 if (init_vec != NULL)
12269 release_tree_vector (init_vec);
12275 return delete_sanity
12276 (RECUR (TREE_OPERAND (t, 0)),
12277 RECUR (TREE_OPERAND (t, 1)),
12278 DELETE_EXPR_USE_VEC (t),
12279 DELETE_EXPR_USE_GLOBAL (t));
12281 case COMPOUND_EXPR:
12282 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12283 RECUR (TREE_OPERAND (t, 1)),
12289 VEC(tree,gc) *call_args;
12290 unsigned int nargs, i;
12295 function = CALL_EXPR_FN (t);
12296 /* When we parsed the expression, we determined whether or
12297 not Koenig lookup should be performed. */
12298 koenig_p = KOENIG_LOOKUP_P (t);
12299 if (TREE_CODE (function) == SCOPE_REF)
12301 qualified_p = true;
12302 function = tsubst_qualified_id (function, args, complain, in_decl,
12304 /*address_p=*/false);
12308 if (TREE_CODE (function) == COMPONENT_REF)
12310 tree op = TREE_OPERAND (function, 1);
12312 qualified_p = (TREE_CODE (op) == SCOPE_REF
12313 || (BASELINK_P (op)
12314 && BASELINK_QUALIFIED_P (op)));
12317 qualified_p = false;
12319 function = tsubst_copy_and_build (function, args, complain,
12322 integral_constant_expression_p);
12324 if (BASELINK_P (function))
12325 qualified_p = true;
12328 nargs = call_expr_nargs (t);
12329 call_args = make_tree_vector ();
12330 for (i = 0; i < nargs; ++i)
12332 tree arg = CALL_EXPR_ARG (t, i);
12334 if (!PACK_EXPANSION_P (arg))
12335 VEC_safe_push (tree, gc, call_args,
12336 RECUR (CALL_EXPR_ARG (t, i)));
12339 /* Expand the pack expansion and push each entry onto
12341 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12342 if (TREE_CODE (arg) == TREE_VEC)
12344 unsigned int len, j;
12346 len = TREE_VEC_LENGTH (arg);
12347 for (j = 0; j < len; ++j)
12349 tree value = TREE_VEC_ELT (arg, j);
12350 if (value != NULL_TREE)
12351 value = convert_from_reference (value);
12352 VEC_safe_push (tree, gc, call_args, value);
12357 /* A partial substitution. Add one entry. */
12358 VEC_safe_push (tree, gc, call_args, arg);
12363 /* We do not perform argument-dependent lookup if normal
12364 lookup finds a non-function, in accordance with the
12365 expected resolution of DR 218. */
12367 && ((is_overloaded_fn (function)
12368 /* If lookup found a member function, the Koenig lookup is
12369 not appropriate, even if an unqualified-name was used
12370 to denote the function. */
12371 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12372 || TREE_CODE (function) == IDENTIFIER_NODE)
12373 /* Only do this when substitution turns a dependent call
12374 into a non-dependent call. */
12375 && type_dependent_expression_p_push (t)
12376 && !any_type_dependent_arguments_p (call_args))
12377 function = perform_koenig_lookup (function, call_args);
12379 if (TREE_CODE (function) == IDENTIFIER_NODE)
12381 unqualified_name_lookup_error (function);
12382 release_tree_vector (call_args);
12383 return error_mark_node;
12386 /* Remember that there was a reference to this entity. */
12387 if (DECL_P (function))
12388 mark_used (function);
12390 if (TREE_CODE (function) == OFFSET_REF)
12391 ret = build_offset_ref_call_from_tree (function, &call_args);
12392 else if (TREE_CODE (function) == COMPONENT_REF)
12394 if (!BASELINK_P (TREE_OPERAND (function, 1)))
12395 ret = finish_call_expr (function, &call_args,
12396 /*disallow_virtual=*/false,
12397 /*koenig_p=*/false,
12400 ret = (build_new_method_call
12401 (TREE_OPERAND (function, 0),
12402 TREE_OPERAND (function, 1),
12403 &call_args, NULL_TREE,
12404 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12409 ret = finish_call_expr (function, &call_args,
12410 /*disallow_virtual=*/qualified_p,
12414 release_tree_vector (call_args);
12420 return build_x_conditional_expr
12421 (RECUR (TREE_OPERAND (t, 0)),
12422 RECUR (TREE_OPERAND (t, 1)),
12423 RECUR (TREE_OPERAND (t, 2)),
12426 case PSEUDO_DTOR_EXPR:
12427 return finish_pseudo_destructor_expr
12428 (RECUR (TREE_OPERAND (t, 0)),
12429 RECUR (TREE_OPERAND (t, 1)),
12430 RECUR (TREE_OPERAND (t, 2)));
12434 tree purpose, value, chain;
12436 if (t == void_list_node)
12439 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12440 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12442 /* We have pack expansions, so expand those and
12443 create a new list out of it. */
12444 tree purposevec = NULL_TREE;
12445 tree valuevec = NULL_TREE;
12449 /* Expand the argument expressions. */
12450 if (TREE_PURPOSE (t))
12451 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12452 complain, in_decl);
12453 if (TREE_VALUE (t))
12454 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12455 complain, in_decl);
12457 /* Build the rest of the list. */
12458 chain = TREE_CHAIN (t);
12459 if (chain && chain != void_type_node)
12460 chain = RECUR (chain);
12462 /* Determine the number of arguments. */
12463 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12465 len = TREE_VEC_LENGTH (purposevec);
12466 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12468 else if (TREE_CODE (valuevec) == TREE_VEC)
12469 len = TREE_VEC_LENGTH (valuevec);
12472 /* Since we only performed a partial substitution into
12473 the argument pack, we only return a single list
12475 if (purposevec == TREE_PURPOSE (t)
12476 && valuevec == TREE_VALUE (t)
12477 && chain == TREE_CHAIN (t))
12480 return tree_cons (purposevec, valuevec, chain);
12483 /* Convert the argument vectors into a TREE_LIST */
12487 /* Grab the Ith values. */
12489 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12492 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12495 /* Build the list (backwards). */
12496 chain = tree_cons (purpose, value, chain);
12502 purpose = TREE_PURPOSE (t);
12504 purpose = RECUR (purpose);
12505 value = TREE_VALUE (t);
12507 value = RECUR (value);
12508 chain = TREE_CHAIN (t);
12509 if (chain && chain != void_type_node)
12510 chain = RECUR (chain);
12511 if (purpose == TREE_PURPOSE (t)
12512 && value == TREE_VALUE (t)
12513 && chain == TREE_CHAIN (t))
12515 return tree_cons (purpose, value, chain);
12518 case COMPONENT_REF:
12524 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12525 args, complain, in_decl);
12526 /* Remember that there was a reference to this entity. */
12527 if (DECL_P (object))
12528 mark_used (object);
12529 object_type = TREE_TYPE (object);
12531 member = TREE_OPERAND (t, 1);
12532 if (BASELINK_P (member))
12533 member = tsubst_baselink (member,
12534 non_reference (TREE_TYPE (object)),
12535 args, complain, in_decl);
12537 member = tsubst_copy (member, args, complain, in_decl);
12538 if (member == error_mark_node)
12539 return error_mark_node;
12541 if (object_type && !CLASS_TYPE_P (object_type))
12543 if (SCALAR_TYPE_P (object_type))
12545 tree s = NULL_TREE;
12546 tree dtor = member;
12548 if (TREE_CODE (dtor) == SCOPE_REF)
12550 s = TREE_OPERAND (dtor, 0);
12551 dtor = TREE_OPERAND (dtor, 1);
12553 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12555 dtor = TREE_OPERAND (dtor, 0);
12557 return finish_pseudo_destructor_expr (object, s, dtor);
12561 else if (TREE_CODE (member) == SCOPE_REF
12562 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12567 /* Lookup the template functions now that we know what the
12569 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12570 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12571 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12572 /*is_type_p=*/false,
12573 /*complain=*/false);
12574 if (BASELINK_P (member))
12576 BASELINK_FUNCTIONS (member)
12577 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12579 member = (adjust_result_of_qualified_name_lookup
12580 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12585 qualified_name_lookup_error (object_type, tmpl, member,
12587 return error_mark_node;
12590 else if (TREE_CODE (member) == SCOPE_REF
12591 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12592 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12594 if (complain & tf_error)
12596 if (TYPE_P (TREE_OPERAND (member, 0)))
12597 error ("%qT is not a class or namespace",
12598 TREE_OPERAND (member, 0));
12600 error ("%qD is not a class or namespace",
12601 TREE_OPERAND (member, 0));
12603 return error_mark_node;
12605 else if (TREE_CODE (member) == FIELD_DECL)
12606 return finish_non_static_data_member (member, object, NULL_TREE);
12608 return finish_class_member_access_expr (object, member,
12609 /*template_p=*/false,
12615 (RECUR (TREE_OPERAND (t, 0)));
12619 VEC(constructor_elt,gc) *n;
12620 constructor_elt *ce;
12621 unsigned HOST_WIDE_INT idx;
12622 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12623 bool process_index_p;
12625 bool need_copy_p = false;
12628 if (type == error_mark_node)
12629 return error_mark_node;
12631 /* digest_init will do the wrong thing if we let it. */
12632 if (type && TYPE_PTRMEMFUNC_P (type))
12635 /* We do not want to process the index of aggregate
12636 initializers as they are identifier nodes which will be
12637 looked up by digest_init. */
12638 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12640 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12641 newlen = VEC_length (constructor_elt, n);
12642 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12644 if (ce->index && process_index_p)
12645 ce->index = RECUR (ce->index);
12647 if (PACK_EXPANSION_P (ce->value))
12649 /* Substitute into the pack expansion. */
12650 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12653 if (ce->value == error_mark_node)
12655 else if (TREE_VEC_LENGTH (ce->value) == 1)
12656 /* Just move the argument into place. */
12657 ce->value = TREE_VEC_ELT (ce->value, 0);
12660 /* Update the length of the final CONSTRUCTOR
12661 arguments vector, and note that we will need to
12663 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12664 need_copy_p = true;
12668 ce->value = RECUR (ce->value);
12673 VEC(constructor_elt,gc) *old_n = n;
12675 n = VEC_alloc (constructor_elt, gc, newlen);
12676 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12679 if (TREE_CODE (ce->value) == TREE_VEC)
12681 int i, len = TREE_VEC_LENGTH (ce->value);
12682 for (i = 0; i < len; ++i)
12683 CONSTRUCTOR_APPEND_ELT (n, 0,
12684 TREE_VEC_ELT (ce->value, i));
12687 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12691 r = build_constructor (init_list_type_node, n);
12692 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12694 if (TREE_HAS_CONSTRUCTOR (t))
12695 return finish_compound_literal (type, r);
12702 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12703 if (TYPE_P (operand_0))
12704 return get_typeid (operand_0);
12705 return build_typeid (operand_0);
12715 tree r = tsubst_copy (t, args, complain, in_decl);
12717 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12718 /* If the original type was a reference, we'll be wrapped in
12719 the appropriate INDIRECT_REF. */
12720 r = convert_from_reference (r);
12725 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12726 tsubst_copy (TREE_TYPE (t), args, complain,
12729 case OFFSETOF_EXPR:
12730 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12734 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12735 complain, in_decl);
12737 tree type2 = TRAIT_EXPR_TYPE2 (t);
12739 type2 = tsubst_copy (type2, args, complain, in_decl);
12741 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12746 tree old_stmt_expr = cur_stmt_expr;
12747 tree stmt_expr = begin_stmt_expr ();
12749 cur_stmt_expr = stmt_expr;
12750 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12751 integral_constant_expression_p);
12752 stmt_expr = finish_stmt_expr (stmt_expr, false);
12753 cur_stmt_expr = old_stmt_expr;
12755 /* If the resulting list of expression statement is empty,
12756 fold it further into void_zero_node. */
12757 if (empty_expr_stmt_p (stmt_expr))
12758 stmt_expr = void_zero_node;
12764 t = tsubst_copy (t, args, complain, in_decl);
12765 /* As in finish_id_expression, we resolve enumeration constants
12766 to their underlying values. */
12767 if (TREE_CODE (t) == CONST_DECL)
12769 used_types_insert (TREE_TYPE (t));
12770 return DECL_INITIAL (t);
12776 tree r = build_lambda_expr ();
12778 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12779 TREE_TYPE (r) = type;
12780 CLASSTYPE_LAMBDA_EXPR (type) = r;
12782 LAMBDA_EXPR_LOCATION (r)
12783 = LAMBDA_EXPR_LOCATION (t);
12784 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12785 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12786 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12787 LAMBDA_EXPR_DISCRIMINATOR (r)
12788 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12789 LAMBDA_EXPR_CAPTURE_LIST (r)
12790 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12791 LAMBDA_EXPR_THIS_CAPTURE (r)
12792 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12793 LAMBDA_EXPR_EXTRA_SCOPE (r)
12794 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12796 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12797 determine_visibility (TYPE_NAME (type));
12798 /* Now that we know visibility, instantiate the type so we have a
12799 declaration of the op() for later calls to lambda_function. */
12800 complete_type (type);
12802 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12804 apply_lambda_return_type (r, type);
12806 return build_lambda_object (r);
12810 /* Handle Objective-C++ constructs, if appropriate. */
12813 = objcp_tsubst_copy_and_build (t, args, complain,
12814 in_decl, /*function_p=*/false);
12818 return tsubst_copy (t, args, complain, in_decl);
12824 /* Verify that the instantiated ARGS are valid. For type arguments,
12825 make sure that the type's linkage is ok. For non-type arguments,
12826 make sure they are constants if they are integral or enumerations.
12827 Emit an error under control of COMPLAIN, and return TRUE on error. */
12830 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12832 if (ARGUMENT_PACK_P (t))
12834 tree vec = ARGUMENT_PACK_ARGS (t);
12835 int len = TREE_VEC_LENGTH (vec);
12836 bool result = false;
12839 for (i = 0; i < len; ++i)
12840 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12844 else if (TYPE_P (t))
12846 /* [basic.link]: A name with no linkage (notably, the name
12847 of a class or enumeration declared in a local scope)
12848 shall not be used to declare an entity with linkage.
12849 This implies that names with no linkage cannot be used as
12852 DR 757 relaxes this restriction for C++0x. */
12853 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
12854 : no_linkage_check (t, /*relaxed_p=*/false));
12858 /* DR 488 makes use of a type with no linkage cause
12859 type deduction to fail. */
12860 if (complain & tf_error)
12862 if (TYPE_ANONYMOUS_P (nt))
12863 error ("%qT is/uses anonymous type", t);
12865 error ("template argument for %qD uses local type %qT",
12870 /* In order to avoid all sorts of complications, we do not
12871 allow variably-modified types as template arguments. */
12872 else if (variably_modified_type_p (t, NULL_TREE))
12874 if (complain & tf_error)
12875 error ("%qT is a variably modified type", t);
12879 /* A non-type argument of integral or enumerated type must be a
12881 else if (TREE_TYPE (t)
12882 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12883 && !TREE_CONSTANT (t))
12885 if (complain & tf_error)
12886 error ("integral expression %qE is not constant", t);
12893 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12895 int ix, len = DECL_NTPARMS (tmpl);
12896 bool result = false;
12898 for (ix = 0; ix != len; ix++)
12900 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12903 if (result && (complain & tf_error))
12904 error (" trying to instantiate %qD", tmpl);
12908 /* Instantiate the indicated variable or function template TMPL with
12909 the template arguments in TARG_PTR. */
12912 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12914 tree targ_ptr = orig_args;
12918 HOST_WIDE_INT saved_processing_template_decl;
12920 if (tmpl == error_mark_node)
12921 return error_mark_node;
12923 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12925 /* If this function is a clone, handle it specially. */
12926 if (DECL_CLONED_FUNCTION_P (tmpl))
12931 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12932 DECL_CLONED_FUNCTION. */
12933 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12934 targ_ptr, complain);
12935 if (spec == error_mark_node)
12936 return error_mark_node;
12938 /* Look for the clone. */
12939 FOR_EACH_CLONE (clone, spec)
12940 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12942 /* We should always have found the clone by now. */
12943 gcc_unreachable ();
12947 /* Check to see if we already have this specialization. */
12948 gen_tmpl = most_general_template (tmpl);
12949 if (tmpl != gen_tmpl)
12950 /* The TMPL is a partial instantiation. To get a full set of
12951 arguments we must add the arguments used to perform the
12952 partial instantiation. */
12953 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12956 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12957 but it doesn't seem to be on the hot path. */
12958 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12960 gcc_assert (tmpl == gen_tmpl
12961 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12963 || fndecl == NULL_TREE);
12965 if (spec != NULL_TREE)
12968 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12970 return error_mark_node;
12972 /* We are building a FUNCTION_DECL, during which the access of its
12973 parameters and return types have to be checked. However this
12974 FUNCTION_DECL which is the desired context for access checking
12975 is not built yet. We solve this chicken-and-egg problem by
12976 deferring all checks until we have the FUNCTION_DECL. */
12977 push_deferring_access_checks (dk_deferred);
12979 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12980 (because, for example, we have encountered a non-dependent
12981 function call in the body of a template function and must now
12982 determine which of several overloaded functions will be called),
12983 within the instantiation itself we are not processing a
12985 saved_processing_template_decl = processing_template_decl;
12986 processing_template_decl = 0;
12987 /* Substitute template parameters to obtain the specialization. */
12988 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12989 targ_ptr, complain, gen_tmpl);
12990 processing_template_decl = saved_processing_template_decl;
12991 if (fndecl == error_mark_node)
12992 return error_mark_node;
12994 /* Now we know the specialization, compute access previously
12996 push_access_scope (fndecl);
12998 /* Some typedefs referenced from within the template code need to be access
12999 checked at template instantiation time, i.e now. These types were
13000 added to the template at parsing time. Let's get those and perfom
13001 the acces checks then. */
13002 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
13003 perform_deferred_access_checks ();
13004 pop_access_scope (fndecl);
13005 pop_deferring_access_checks ();
13007 /* The DECL_TI_TEMPLATE should always be the immediate parent
13008 template, not the most general template. */
13009 DECL_TI_TEMPLATE (fndecl) = tmpl;
13011 /* If we've just instantiated the main entry point for a function,
13012 instantiate all the alternate entry points as well. We do this
13013 by cloning the instantiation of the main entry point, not by
13014 instantiating the template clones. */
13015 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
13016 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
13021 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
13022 NARGS elements of the arguments that are being used when calling
13023 it. TARGS is a vector into which the deduced template arguments
13026 Return zero for success, 2 for an incomplete match that doesn't resolve
13027 all the types, and 1 for complete failure. An error message will be
13028 printed only for an incomplete match.
13030 If FN is a conversion operator, or we are trying to produce a specific
13031 specialization, RETURN_TYPE is the return type desired.
13033 The EXPLICIT_TARGS are explicit template arguments provided via a
13036 The parameter STRICT is one of:
13039 We are deducing arguments for a function call, as in
13040 [temp.deduct.call].
13043 We are deducing arguments for a conversion function, as in
13044 [temp.deduct.conv].
13047 We are deducing arguments when doing an explicit instantiation
13048 as in [temp.explicit], when determining an explicit specialization
13049 as in [temp.expl.spec], or when taking the address of a function
13050 template, as in [temp.deduct.funcaddr]. */
13053 fn_type_unification (tree fn,
13054 tree explicit_targs,
13057 unsigned int nargs,
13059 unification_kind_t strict,
13065 bool incomplete_argument_packs_p = false;
13067 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13069 fntype = TREE_TYPE (fn);
13070 if (explicit_targs)
13074 The specified template arguments must match the template
13075 parameters in kind (i.e., type, nontype, template), and there
13076 must not be more arguments than there are parameters;
13077 otherwise type deduction fails.
13079 Nontype arguments must match the types of the corresponding
13080 nontype template parameters, or must be convertible to the
13081 types of the corresponding nontype parameters as specified in
13082 _temp.arg.nontype_, otherwise type deduction fails.
13084 All references in the function type of the function template
13085 to the corresponding template parameters are replaced by the
13086 specified template argument values. If a substitution in a
13087 template parameter or in the function type of the function
13088 template results in an invalid type, type deduction fails. */
13089 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13090 int i, len = TREE_VEC_LENGTH (tparms);
13091 tree converted_args;
13092 bool incomplete = false;
13094 if (explicit_targs == error_mark_node)
13098 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13099 /*require_all_args=*/false,
13100 /*use_default_args=*/false));
13101 if (converted_args == error_mark_node)
13104 /* Substitute the explicit args into the function type. This is
13105 necessary so that, for instance, explicitly declared function
13106 arguments can match null pointed constants. If we were given
13107 an incomplete set of explicit args, we must not do semantic
13108 processing during substitution as we could create partial
13110 for (i = 0; i < len; i++)
13112 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13113 bool parameter_pack = false;
13115 /* Dig out the actual parm. */
13116 if (TREE_CODE (parm) == TYPE_DECL
13117 || TREE_CODE (parm) == TEMPLATE_DECL)
13119 parm = TREE_TYPE (parm);
13120 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13122 else if (TREE_CODE (parm) == PARM_DECL)
13124 parm = DECL_INITIAL (parm);
13125 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13128 if (parameter_pack)
13132 template_parm_level_and_index (parm, &level, &idx);
13134 /* Mark the argument pack as "incomplete". We could
13135 still deduce more arguments during unification. */
13136 targ = TMPL_ARG (converted_args, level, idx);
13139 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13140 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13141 = ARGUMENT_PACK_ARGS (targ);
13144 /* We have some incomplete argument packs. */
13145 incomplete_argument_packs_p = true;
13149 if (incomplete_argument_packs_p)
13150 /* Any substitution is guaranteed to be incomplete if there
13151 are incomplete argument packs, because we can still deduce
13155 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13157 processing_template_decl += incomplete;
13158 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
13159 processing_template_decl -= incomplete;
13161 if (fntype == error_mark_node)
13164 /* Place the explicitly specified arguments in TARGS. */
13165 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13166 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13169 /* Never do unification on the 'this' parameter. */
13170 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13176 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13177 new_args = XALLOCAVEC (tree, nargs + 1);
13178 new_args[0] = return_type;
13179 memcpy (new_args + 1, args, nargs * sizeof (tree));
13184 /* We allow incomplete unification without an error message here
13185 because the standard doesn't seem to explicitly prohibit it. Our
13186 callers must be ready to deal with unification failures in any
13188 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13189 targs, parms, args, nargs, /*subr=*/0,
13192 if (result == 0 && incomplete_argument_packs_p)
13194 int i, len = NUM_TMPL_ARGS (targs);
13196 /* Clear the "incomplete" flags on all argument packs. */
13197 for (i = 0; i < len; i++)
13199 tree arg = TREE_VEC_ELT (targs, i);
13200 if (ARGUMENT_PACK_P (arg))
13202 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
13203 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
13208 /* Now that we have bindings for all of the template arguments,
13209 ensure that the arguments deduced for the template template
13210 parameters have compatible template parameter lists. We cannot
13211 check this property before we have deduced all template
13212 arguments, because the template parameter types of a template
13213 template parameter might depend on prior template parameters
13214 deduced after the template template parameter. The following
13215 ill-formed example illustrates this issue:
13217 template<typename T, template<T> class C> void f(C<5>, T);
13219 template<int N> struct X {};
13222 f(X<5>(), 5l); // error: template argument deduction fails
13225 The template parameter list of 'C' depends on the template type
13226 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13227 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13228 time that we deduce 'C'. */
13230 && !template_template_parm_bindings_ok_p
13231 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
13235 /* All is well so far. Now, check:
13239 When all template arguments have been deduced, all uses of
13240 template parameters in nondeduced contexts are replaced with
13241 the corresponding deduced argument values. If the
13242 substitution results in an invalid type, as described above,
13243 type deduction fails. */
13245 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
13246 if (substed == error_mark_node)
13249 /* If we're looking for an exact match, check that what we got
13250 is indeed an exact match. It might not be if some template
13251 parameters are used in non-deduced contexts. */
13252 if (strict == DEDUCE_EXACT)
13257 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
13259 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
13260 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
13261 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13269 /* Adjust types before performing type deduction, as described in
13270 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
13271 sections are symmetric. PARM is the type of a function parameter
13272 or the return type of the conversion function. ARG is the type of
13273 the argument passed to the call, or the type of the value
13274 initialized with the result of the conversion function.
13275 ARG_EXPR is the original argument expression, which may be null. */
13278 maybe_adjust_types_for_deduction (unification_kind_t strict,
13292 /* Swap PARM and ARG throughout the remainder of this
13293 function; the handling is precisely symmetric since PARM
13294 will initialize ARG rather than vice versa. */
13302 /* Core issue #873: Do the DR606 thing (see below) for these cases,
13303 too, but here handle it by stripping the reference from PARM
13304 rather than by adding it to ARG. */
13305 if (TREE_CODE (*parm) == REFERENCE_TYPE
13306 && TYPE_REF_IS_RVALUE (*parm)
13307 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13308 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13309 && TREE_CODE (*arg) == REFERENCE_TYPE
13310 && !TYPE_REF_IS_RVALUE (*arg))
13311 *parm = TREE_TYPE (*parm);
13312 /* Nothing else to do in this case. */
13316 gcc_unreachable ();
13319 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13321 /* [temp.deduct.call]
13323 If P is not a reference type:
13325 --If A is an array type, the pointer type produced by the
13326 array-to-pointer standard conversion (_conv.array_) is
13327 used in place of A for type deduction; otherwise,
13329 --If A is a function type, the pointer type produced by
13330 the function-to-pointer standard conversion
13331 (_conv.func_) is used in place of A for type deduction;
13334 --If A is a cv-qualified type, the top level
13335 cv-qualifiers of A's type are ignored for type
13337 if (TREE_CODE (*arg) == ARRAY_TYPE)
13338 *arg = build_pointer_type (TREE_TYPE (*arg));
13339 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13340 *arg = build_pointer_type (*arg);
13342 *arg = TYPE_MAIN_VARIANT (*arg);
13345 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13346 of the form T&&, where T is a template parameter, and the argument
13347 is an lvalue, T is deduced as A& */
13348 if (TREE_CODE (*parm) == REFERENCE_TYPE
13349 && TYPE_REF_IS_RVALUE (*parm)
13350 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13351 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13352 && arg_expr && real_lvalue_p (arg_expr))
13353 *arg = build_reference_type (*arg);
13355 /* [temp.deduct.call]
13357 If P is a cv-qualified type, the top level cv-qualifiers
13358 of P's type are ignored for type deduction. If P is a
13359 reference type, the type referred to by P is used for
13361 *parm = TYPE_MAIN_VARIANT (*parm);
13362 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13364 *parm = TREE_TYPE (*parm);
13365 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13368 /* DR 322. For conversion deduction, remove a reference type on parm
13369 too (which has been swapped into ARG). */
13370 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13371 *arg = TREE_TYPE (*arg);
13376 /* Most parms like fn_type_unification.
13378 If SUBR is 1, we're being called recursively (to unify the
13379 arguments of a function or method parameter of a function
13383 type_unification_real (tree tparms,
13387 unsigned int xnargs,
13389 unification_kind_t strict,
13392 tree parm, arg, arg_expr;
13394 int ntparms = TREE_VEC_LENGTH (tparms);
13396 int saw_undeduced = 0;
13399 unsigned int nargs;
13402 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13403 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13404 gcc_assert (ntparms > 0);
13406 /* Reset the number of non-defaulted template arguments contained
13408 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
13413 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13414 | UNIFY_ALLOW_DERIVED);
13418 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13422 sub_strict = UNIFY_ALLOW_NONE;
13426 gcc_unreachable ();
13435 while (parms && parms != void_list_node
13438 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13441 parm = TREE_VALUE (parms);
13442 parms = TREE_CHAIN (parms);
13447 if (arg == error_mark_node)
13449 if (arg == unknown_type_node)
13450 /* We can't deduce anything from this, but we might get all the
13451 template args from other function args. */
13454 /* Conversions will be performed on a function argument that
13455 corresponds with a function parameter that contains only
13456 non-deducible template parameters and explicitly specified
13457 template parameters. */
13458 if (!uses_template_parms (parm))
13463 type = TREE_TYPE (arg);
13467 if (same_type_p (parm, type))
13469 if (strict != DEDUCE_EXACT
13470 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13479 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13480 if (type_unknown_p (arg))
13482 /* [temp.deduct.type]
13484 A template-argument can be deduced from a pointer to
13485 function or pointer to member function argument if
13486 the set of overloaded functions does not contain
13487 function templates and at most one of a set of
13488 overloaded functions provides a unique match. */
13489 if (resolve_overloaded_unification
13490 (tparms, targs, parm, arg, strict, sub_strict))
13496 arg = unlowered_expr_type (arg);
13497 if (arg == error_mark_node)
13502 int arg_strict = sub_strict;
13505 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13508 if (arg == init_list_type_node && arg_expr)
13510 if (unify (tparms, targs, parm, arg, arg_strict))
13517 && parms != void_list_node
13518 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13520 /* Unify the remaining arguments with the pack expansion type. */
13522 tree parmvec = make_tree_vec (1);
13524 /* Allocate a TREE_VEC and copy in all of the arguments */
13525 argvec = make_tree_vec (nargs - ia);
13526 for (i = 0; ia < nargs; ++ia, ++i)
13527 TREE_VEC_ELT (argvec, i) = args[ia];
13529 /* Copy the parameter into parmvec. */
13530 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13531 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13532 /*call_args_p=*/true, /*subr=*/subr))
13535 /* Advance to the end of the list of parameters. */
13536 parms = TREE_CHAIN (parms);
13539 /* Fail if we've reached the end of the parm list, and more args
13540 are present, and the parm list isn't variadic. */
13541 if (ia < nargs && parms == void_list_node)
13543 /* Fail if parms are left and they don't have default values. */
13544 if (parms && parms != void_list_node
13545 && TREE_PURPOSE (parms) == NULL_TREE)
13549 for (i = 0; i < ntparms; i++)
13550 if (!TREE_VEC_ELT (targs, i))
13554 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13557 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13559 /* If this is an undeduced nontype parameter that depends on
13560 a type parameter, try another pass; its type may have been
13561 deduced from a later argument than the one from which
13562 this parameter can be deduced. */
13563 if (TREE_CODE (tparm) == PARM_DECL
13564 && uses_template_parms (TREE_TYPE (tparm))
13565 && !saw_undeduced++)
13568 /* Core issue #226 (C++0x) [temp.deduct]:
13570 If a template argument has not been deduced, its
13571 default template argument, if any, is used.
13573 When we are in C++98 mode, TREE_PURPOSE will either
13574 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13575 to explicitly check cxx_dialect here. */
13576 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13578 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13579 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13580 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13581 arg = convert_template_argument (parm, arg, targs, tf_none,
13583 if (arg == error_mark_node)
13587 TREE_VEC_ELT (targs, i) = arg;
13588 /* The position of the first default template argument,
13589 is also the number of non-defaulted arguments in TARGS.
13591 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13592 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
13597 /* If the type parameter is a parameter pack, then it will
13598 be deduced to an empty parameter pack. */
13599 if (template_parameter_pack_p (tparm))
13603 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13605 arg = make_node (NONTYPE_ARGUMENT_PACK);
13606 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13607 TREE_CONSTANT (arg) = 1;
13610 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13612 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13614 TREE_VEC_ELT (targs, i) = arg;
13620 #ifdef ENABLE_CHECKING
13621 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13622 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
13628 /* Subroutine of type_unification_real. Args are like the variables
13629 at the call site. ARG is an overloaded function (or template-id);
13630 we try deducing template args from each of the overloads, and if
13631 only one succeeds, we go with that. Modifies TARGS and returns
13632 true on success. */
13635 resolve_overloaded_unification (tree tparms,
13639 unification_kind_t strict,
13642 tree tempargs = copy_node (targs);
13644 tree goodfn = NULL_TREE;
13647 if (TREE_CODE (arg) == ADDR_EXPR)
13649 arg = TREE_OPERAND (arg, 0);
13655 if (TREE_CODE (arg) == COMPONENT_REF)
13656 /* Handle `&x' where `x' is some static or non-static member
13658 arg = TREE_OPERAND (arg, 1);
13660 if (TREE_CODE (arg) == OFFSET_REF)
13661 arg = TREE_OPERAND (arg, 1);
13663 /* Strip baselink information. */
13664 if (BASELINK_P (arg))
13665 arg = BASELINK_FUNCTIONS (arg);
13667 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13669 /* If we got some explicit template args, we need to plug them into
13670 the affected templates before we try to unify, in case the
13671 explicit args will completely resolve the templates in question. */
13673 tree expl_subargs = TREE_OPERAND (arg, 1);
13674 arg = TREE_OPERAND (arg, 0);
13676 for (; arg; arg = OVL_NEXT (arg))
13678 tree fn = OVL_CURRENT (arg);
13679 tree subargs, elem;
13681 if (TREE_CODE (fn) != TEMPLATE_DECL)
13684 ++processing_template_decl;
13685 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13686 expl_subargs, /*check_ret=*/false);
13689 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13690 if (try_one_overload (tparms, targs, tempargs, parm,
13691 elem, strict, sub_strict, addr_p)
13692 && (!goodfn || !decls_match (goodfn, elem)))
13698 --processing_template_decl;
13701 else if (TREE_CODE (arg) != OVERLOAD
13702 && TREE_CODE (arg) != FUNCTION_DECL)
13703 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13704 -- but the deduction does not succeed because the expression is
13705 not just the function on its own. */
13708 for (; arg; arg = OVL_NEXT (arg))
13709 if (try_one_overload (tparms, targs, tempargs, parm,
13710 TREE_TYPE (OVL_CURRENT (arg)),
13711 strict, sub_strict, addr_p)
13712 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13714 goodfn = OVL_CURRENT (arg);
13718 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13719 to function or pointer to member function argument if the set of
13720 overloaded functions does not contain function templates and at most
13721 one of a set of overloaded functions provides a unique match.
13723 So if we found multiple possibilities, we return success but don't
13724 deduce anything. */
13728 int i = TREE_VEC_LENGTH (targs);
13730 if (TREE_VEC_ELT (tempargs, i))
13731 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13739 /* Core DR 115: In contexts where deduction is done and fails, or in
13740 contexts where deduction is not done, if a template argument list is
13741 specified and it, along with any default template arguments, identifies
13742 a single function template specialization, then the template-id is an
13743 lvalue for the function template specialization. */
13746 resolve_nondeduced_context (tree orig_expr)
13748 tree expr, offset, baselink;
13751 if (!type_unknown_p (orig_expr))
13756 offset = NULL_TREE;
13757 baselink = NULL_TREE;
13759 if (TREE_CODE (expr) == ADDR_EXPR)
13761 expr = TREE_OPERAND (expr, 0);
13764 if (TREE_CODE (expr) == OFFSET_REF)
13767 expr = TREE_OPERAND (expr, 1);
13769 if (TREE_CODE (expr) == BASELINK)
13772 expr = BASELINK_FUNCTIONS (expr);
13775 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13778 tree goodfn = NULL_TREE;
13780 /* If we got some explicit template args, we need to plug them into
13781 the affected templates before we try to unify, in case the
13782 explicit args will completely resolve the templates in question. */
13784 tree expl_subargs = TREE_OPERAND (expr, 1);
13785 tree arg = TREE_OPERAND (expr, 0);
13786 tree badfn = NULL_TREE;
13787 tree badargs = NULL_TREE;
13789 for (; arg; arg = OVL_NEXT (arg))
13791 tree fn = OVL_CURRENT (arg);
13792 tree subargs, elem;
13794 if (TREE_CODE (fn) != TEMPLATE_DECL)
13797 ++processing_template_decl;
13798 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13799 expl_subargs, /*check_ret=*/false);
13800 if (subargs && !any_dependent_template_arguments_p (subargs))
13802 elem = instantiate_template (fn, subargs, tf_none);
13803 if (elem == error_mark_node)
13808 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13814 --processing_template_decl;
13820 expr = build_baselink (BASELINK_BINFO (baselink),
13821 BASELINK_ACCESS_BINFO (baselink),
13822 expr, BASELINK_OPTYPE (baselink));
13824 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13825 TREE_OPERAND (offset, 0), expr);
13827 expr = build_address (expr);
13830 else if (good == 0 && badargs)
13831 /* There were no good options and at least one bad one, so let the
13832 user know what the problem is. */
13833 instantiate_template (badfn, badargs, tf_warning_or_error);
13838 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13839 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13840 different overloads deduce different arguments for a given parm.
13841 ADDR_P is true if the expression for which deduction is being
13842 performed was of the form "& fn" rather than simply "fn".
13844 Returns 1 on success. */
13847 try_one_overload (tree tparms,
13852 unification_kind_t strict,
13860 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13861 to function or pointer to member function argument if the set of
13862 overloaded functions does not contain function templates and at most
13863 one of a set of overloaded functions provides a unique match.
13865 So if this is a template, just return success. */
13867 if (uses_template_parms (arg))
13870 if (TREE_CODE (arg) == METHOD_TYPE)
13871 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13873 arg = build_pointer_type (arg);
13875 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13877 /* We don't copy orig_targs for this because if we have already deduced
13878 some template args from previous args, unify would complain when we
13879 try to deduce a template parameter for the same argument, even though
13880 there isn't really a conflict. */
13881 nargs = TREE_VEC_LENGTH (targs);
13882 tempargs = make_tree_vec (nargs);
13884 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13887 /* First make sure we didn't deduce anything that conflicts with
13888 explicitly specified args. */
13889 for (i = nargs; i--; )
13891 tree elt = TREE_VEC_ELT (tempargs, i);
13892 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13896 else if (uses_template_parms (elt))
13897 /* Since we're unifying against ourselves, we will fill in
13898 template args used in the function parm list with our own
13899 template parms. Discard them. */
13900 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13901 else if (oldelt && !template_args_equal (oldelt, elt))
13905 for (i = nargs; i--; )
13907 tree elt = TREE_VEC_ELT (tempargs, i);
13910 TREE_VEC_ELT (targs, i) = elt;
13916 /* PARM is a template class (perhaps with unbound template
13917 parameters). ARG is a fully instantiated type. If ARG can be
13918 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13919 TARGS are as for unify. */
13922 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13924 tree copy_of_targs;
13926 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13927 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13928 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13931 /* We need to make a new template argument vector for the call to
13932 unify. If we used TARGS, we'd clutter it up with the result of
13933 the attempted unification, even if this class didn't work out.
13934 We also don't want to commit ourselves to all the unifications
13935 we've already done, since unification is supposed to be done on
13936 an argument-by-argument basis. In other words, consider the
13937 following pathological case:
13939 template <int I, int J, int K>
13942 template <int I, int J>
13943 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13945 template <int I, int J, int K>
13946 void f(S<I, J, K>, S<I, I, I>);
13955 Now, by the time we consider the unification involving `s2', we
13956 already know that we must have `f<0, 0, 0>'. But, even though
13957 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13958 because there are two ways to unify base classes of S<0, 1, 2>
13959 with S<I, I, I>. If we kept the already deduced knowledge, we
13960 would reject the possibility I=1. */
13961 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13963 /* If unification failed, we're done. */
13964 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13965 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13971 /* Given a template type PARM and a class type ARG, find the unique
13972 base type in ARG that is an instance of PARM. We do not examine
13973 ARG itself; only its base-classes. If there is not exactly one
13974 appropriate base class, return NULL_TREE. PARM may be the type of
13975 a partial specialization, as well as a plain template type. Used
13979 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13981 tree rval = NULL_TREE;
13984 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13986 binfo = TYPE_BINFO (complete_type (arg));
13988 /* The type could not be completed. */
13991 /* Walk in inheritance graph order. The search order is not
13992 important, and this avoids multiple walks of virtual bases. */
13993 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13995 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13999 /* If there is more than one satisfactory baseclass, then:
14003 If they yield more than one possible deduced A, the type
14007 if (rval && !same_type_p (r, rval))
14017 /* Returns the level of DECL, which declares a template parameter. */
14020 template_decl_level (tree decl)
14022 switch (TREE_CODE (decl))
14025 case TEMPLATE_DECL:
14026 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
14029 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
14032 gcc_unreachable ();
14037 /* Decide whether ARG can be unified with PARM, considering only the
14038 cv-qualifiers of each type, given STRICT as documented for unify.
14039 Returns nonzero iff the unification is OK on that basis. */
14042 check_cv_quals_for_unify (int strict, tree arg, tree parm)
14044 int arg_quals = cp_type_quals (arg);
14045 int parm_quals = cp_type_quals (parm);
14047 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14048 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14050 /* Although a CVR qualifier is ignored when being applied to a
14051 substituted template parameter ([8.3.2]/1 for example), that
14052 does not apply during deduction [14.8.2.4]/1, (even though
14053 that is not explicitly mentioned, [14.8.2.4]/9 indicates
14054 this). Except when we're allowing additional CV qualifiers
14055 at the outer level [14.8.2.1]/3,1st bullet. */
14056 if ((TREE_CODE (arg) == REFERENCE_TYPE
14057 || TREE_CODE (arg) == FUNCTION_TYPE
14058 || TREE_CODE (arg) == METHOD_TYPE)
14059 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14062 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14063 && (parm_quals & TYPE_QUAL_RESTRICT))
14067 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14068 && (arg_quals & parm_quals) != parm_quals)
14071 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14072 && (parm_quals & arg_quals) != arg_quals)
14078 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14080 template_parm_level_and_index (tree parm, int* level, int* index)
14082 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14083 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14084 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14086 *index = TEMPLATE_TYPE_IDX (parm);
14087 *level = TEMPLATE_TYPE_LEVEL (parm);
14091 *index = TEMPLATE_PARM_IDX (parm);
14092 *level = TEMPLATE_PARM_LEVEL (parm);
14096 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14097 expansion at the end of PACKED_PARMS. Returns 0 if the type
14098 deduction succeeds, 1 otherwise. STRICT is the same as in
14099 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14100 call argument list. We'll need to adjust the arguments to make them
14101 types. SUBR tells us if this is from a recursive call to
14102 type_unification_real. */
14104 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14105 tree packed_args, int strict, bool call_args_p,
14109 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14110 tree pattern = PACK_EXPANSION_PATTERN (parm);
14111 tree pack, packs = NULL_TREE;
14112 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14113 int len = TREE_VEC_LENGTH (packed_args);
14115 /* Determine the parameter packs we will be deducing from the
14116 pattern, and record their current deductions. */
14117 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14118 pack; pack = TREE_CHAIN (pack))
14120 tree parm_pack = TREE_VALUE (pack);
14123 /* Determine the index and level of this parameter pack. */
14124 template_parm_level_and_index (parm_pack, &level, &idx);
14126 /* Keep track of the parameter packs and their corresponding
14128 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14129 TREE_TYPE (packs) = make_tree_vec (len - start);
14132 /* Loop through all of the arguments that have not yet been
14133 unified and unify each with the pattern. */
14134 for (i = start; i < len; i++)
14136 tree parm = pattern;
14138 /* For each parameter pack, clear out the deduced value so that
14139 we can deduce it again. */
14140 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14143 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14145 TMPL_ARG (targs, level, idx) = NULL_TREE;
14148 /* Unify the pattern with the current argument. */
14150 tree arg = TREE_VEC_ELT (packed_args, i);
14151 tree arg_expr = NULL_TREE;
14152 int arg_strict = strict;
14153 bool skip_arg_p = false;
14159 /* This mirrors what we do in type_unification_real. */
14163 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14164 | UNIFY_ALLOW_MORE_CV_QUAL
14165 | UNIFY_ALLOW_DERIVED);
14169 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14173 sub_strict = UNIFY_ALLOW_NONE;
14177 gcc_unreachable ();
14182 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14183 if (type_unknown_p (arg))
14185 /* [temp.deduct.type] A template-argument can be
14186 deduced from a pointer to function or pointer
14187 to member function argument if the set of
14188 overloaded functions does not contain function
14189 templates and at most one of a set of
14190 overloaded functions provides a unique
14193 if (resolve_overloaded_unification
14194 (tparms, targs, parm, arg,
14195 (unification_kind_t) strict,
14205 arg = unlowered_expr_type (arg);
14206 if (arg == error_mark_node)
14211 arg_strict = sub_strict;
14215 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
14216 &parm, &arg, arg_expr);
14221 /* For deduction from an init-list we need the actual list. */
14222 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14224 if (unify (tparms, targs, parm, arg, arg_strict))
14229 /* For each parameter pack, collect the deduced value. */
14230 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14233 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14235 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
14236 TMPL_ARG (targs, level, idx);
14240 /* Verify that the results of unification with the parameter packs
14241 produce results consistent with what we've seen before, and make
14242 the deduced argument packs available. */
14243 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14245 tree old_pack = TREE_VALUE (pack);
14246 tree new_args = TREE_TYPE (pack);
14247 int i, len = TREE_VEC_LENGTH (new_args);
14249 bool nondeduced_p = false;
14251 /* By default keep the original deduced argument pack.
14252 If necessary, more specific code is going to update the
14253 resulting deduced argument later down in this function. */
14254 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14255 TMPL_ARG (targs, level, idx) = old_pack;
14257 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
14258 actually deduce anything. */
14259 for (i = 0; i < len && !nondeduced_p; ++i)
14260 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
14261 nondeduced_p = true;
14265 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
14267 /* Prepend the explicit arguments onto NEW_ARGS. */
14268 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14269 tree old_args = new_args;
14270 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
14271 int len = explicit_len + TREE_VEC_LENGTH (old_args);
14273 /* Copy the explicit arguments. */
14274 new_args = make_tree_vec (len);
14275 for (i = 0; i < explicit_len; i++)
14276 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
14278 /* Copy the deduced arguments. */
14279 for (; i < len; i++)
14280 TREE_VEC_ELT (new_args, i) =
14281 TREE_VEC_ELT (old_args, i - explicit_len);
14287 /* Build the deduced *_ARGUMENT_PACK. */
14288 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
14290 result = make_node (NONTYPE_ARGUMENT_PACK);
14291 TREE_TYPE (result) =
14292 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
14293 TREE_CONSTANT (result) = 1;
14296 result = cxx_make_type (TYPE_ARGUMENT_PACK);
14298 SET_ARGUMENT_PACK_ARGS (result, new_args);
14300 /* Note the deduced argument packs for this parameter
14302 TMPL_ARG (targs, level, idx) = result;
14304 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
14305 && (ARGUMENT_PACK_ARGS (old_pack)
14306 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
14308 /* We only had the explicitly-provided arguments before, but
14309 now we have a complete set of arguments. */
14310 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14312 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
14313 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
14314 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
14316 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
14318 /* Inconsistent unification of this parameter pack. */
14325 /* Deduce the value of template parameters. TPARMS is the (innermost)
14326 set of template parameters to a template. TARGS is the bindings
14327 for those template parameters, as determined thus far; TARGS may
14328 include template arguments for outer levels of template parameters
14329 as well. PARM is a parameter to a template function, or a
14330 subcomponent of that parameter; ARG is the corresponding argument.
14331 This function attempts to match PARM with ARG in a manner
14332 consistent with the existing assignments in TARGS. If more values
14333 are deduced, then TARGS is updated.
14335 Returns 0 if the type deduction succeeds, 1 otherwise. The
14336 parameter STRICT is a bitwise or of the following flags:
14339 Require an exact match between PARM and ARG.
14340 UNIFY_ALLOW_MORE_CV_QUAL:
14341 Allow the deduced ARG to be more cv-qualified (by qualification
14342 conversion) than ARG.
14343 UNIFY_ALLOW_LESS_CV_QUAL:
14344 Allow the deduced ARG to be less cv-qualified than ARG.
14345 UNIFY_ALLOW_DERIVED:
14346 Allow the deduced ARG to be a template base class of ARG,
14347 or a pointer to a template base class of the type pointed to by
14349 UNIFY_ALLOW_INTEGER:
14350 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14351 case for more information.
14352 UNIFY_ALLOW_OUTER_LEVEL:
14353 This is the outermost level of a deduction. Used to determine validity
14354 of qualification conversions. A valid qualification conversion must
14355 have const qualified pointers leading up to the inner type which
14356 requires additional CV quals, except at the outer level, where const
14357 is not required [conv.qual]. It would be normal to set this flag in
14358 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14359 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14360 This is the outermost level of a deduction, and PARM can be more CV
14361 qualified at this point.
14362 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14363 This is the outermost level of a deduction, and PARM can be less CV
14364 qualified at this point. */
14367 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14372 int strict_in = strict;
14374 /* I don't think this will do the right thing with respect to types.
14375 But the only case I've seen it in so far has been array bounds, where
14376 signedness is the only information lost, and I think that will be
14378 while (TREE_CODE (parm) == NOP_EXPR)
14379 parm = TREE_OPERAND (parm, 0);
14381 if (arg == error_mark_node)
14383 if (arg == unknown_type_node
14384 || arg == init_list_type_node)
14385 /* We can't deduce anything from this, but we might get all the
14386 template args from other function args. */
14389 /* If PARM uses template parameters, then we can't bail out here,
14390 even if ARG == PARM, since we won't record unifications for the
14391 template parameters. We might need them if we're trying to
14392 figure out which of two things is more specialized. */
14393 if (arg == parm && !uses_template_parms (parm))
14396 /* Handle init lists early, so the rest of the function can assume
14397 we're dealing with a type. */
14398 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14402 tree orig_parm = parm;
14404 /* Replace T with std::initializer_list<T> for deduction. */
14405 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14406 && flag_deduce_init_list)
14407 parm = listify (parm);
14409 if (!is_std_init_list (parm))
14410 /* We can only deduce from an initializer list argument if the
14411 parameter is std::initializer_list; otherwise this is a
14412 non-deduced context. */
14415 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14417 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14419 int elt_strict = strict;
14420 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14422 tree type = TREE_TYPE (elt);
14423 /* It should only be possible to get here for a call. */
14424 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14425 elt_strict |= maybe_adjust_types_for_deduction
14426 (DEDUCE_CALL, &elttype, &type, elt);
14430 if (unify (tparms, targs, elttype, elt, elt_strict))
14434 /* If the std::initializer_list<T> deduction worked, replace the
14435 deduced A with std::initializer_list<A>. */
14436 if (orig_parm != parm)
14438 idx = TEMPLATE_TYPE_IDX (orig_parm);
14439 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14440 targ = listify (targ);
14441 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14446 /* Immediately reject some pairs that won't unify because of
14447 cv-qualification mismatches. */
14448 if (TREE_CODE (arg) == TREE_CODE (parm)
14450 /* It is the elements of the array which hold the cv quals of an array
14451 type, and the elements might be template type parms. We'll check
14452 when we recurse. */
14453 && TREE_CODE (arg) != ARRAY_TYPE
14454 /* We check the cv-qualifiers when unifying with template type
14455 parameters below. We want to allow ARG `const T' to unify with
14456 PARM `T' for example, when computing which of two templates
14457 is more specialized, for example. */
14458 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14459 && !check_cv_quals_for_unify (strict_in, arg, parm))
14462 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14463 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14464 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14465 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14466 strict &= ~UNIFY_ALLOW_DERIVED;
14467 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14468 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14470 switch (TREE_CODE (parm))
14472 case TYPENAME_TYPE:
14474 case UNBOUND_CLASS_TEMPLATE:
14475 /* In a type which contains a nested-name-specifier, template
14476 argument values cannot be deduced for template parameters used
14477 within the nested-name-specifier. */
14480 case TEMPLATE_TYPE_PARM:
14481 case TEMPLATE_TEMPLATE_PARM:
14482 case BOUND_TEMPLATE_TEMPLATE_PARM:
14483 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14484 if (tparm == error_mark_node)
14487 if (TEMPLATE_TYPE_LEVEL (parm)
14488 != template_decl_level (tparm))
14489 /* The PARM is not one we're trying to unify. Just check
14490 to see if it matches ARG. */
14491 return (TREE_CODE (arg) == TREE_CODE (parm)
14492 && same_type_p (parm, arg)) ? 0 : 1;
14493 idx = TEMPLATE_TYPE_IDX (parm);
14494 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14495 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14497 /* Check for mixed types and values. */
14498 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14499 && TREE_CODE (tparm) != TYPE_DECL)
14500 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14501 && TREE_CODE (tparm) != TEMPLATE_DECL))
14504 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14506 /* ARG must be constructed from a template class or a template
14507 template parameter. */
14508 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14509 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14513 tree parmvec = TYPE_TI_ARGS (parm);
14514 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14516 = DECL_INNERMOST_TEMPLATE_PARMS
14517 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14519 int parm_variadic_p = 0;
14521 /* The resolution to DR150 makes clear that default
14522 arguments for an N-argument may not be used to bind T
14523 to a template template parameter with fewer than N
14524 parameters. It is not safe to permit the binding of
14525 default arguments as an extension, as that may change
14526 the meaning of a conforming program. Consider:
14528 struct Dense { static const unsigned int dim = 1; };
14530 template <template <typename> class View,
14532 void operator+(float, View<Block> const&);
14534 template <typename Block,
14535 unsigned int Dim = Block::dim>
14536 struct Lvalue_proxy { operator float() const; };
14540 Lvalue_proxy<Dense> p;
14545 Here, if Lvalue_proxy is permitted to bind to View, then
14546 the global operator+ will be used; if they are not, the
14547 Lvalue_proxy will be converted to float. */
14548 if (coerce_template_parms (parm_parms,
14550 TYPE_TI_TEMPLATE (parm),
14552 /*require_all_args=*/true,
14553 /*use_default_args=*/false)
14554 == error_mark_node)
14557 /* Deduce arguments T, i from TT<T> or TT<i>.
14558 We check each element of PARMVEC and ARGVEC individually
14559 rather than the whole TREE_VEC since they can have
14560 different number of elements. */
14562 parmvec = expand_template_argument_pack (parmvec);
14563 argvec = expand_template_argument_pack (argvec);
14565 len = TREE_VEC_LENGTH (parmvec);
14567 /* Check if the parameters end in a pack, making them
14570 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14571 parm_variadic_p = 1;
14573 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14576 for (i = 0; i < len - parm_variadic_p; ++i)
14578 if (unify (tparms, targs,
14579 TREE_VEC_ELT (parmvec, i),
14580 TREE_VEC_ELT (argvec, i),
14585 if (parm_variadic_p
14586 && unify_pack_expansion (tparms, targs,
14589 /*call_args_p=*/false,
14593 arg = TYPE_TI_TEMPLATE (arg);
14595 /* Fall through to deduce template name. */
14598 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14599 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14601 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14603 /* Simple cases: Value already set, does match or doesn't. */
14604 if (targ != NULL_TREE && template_args_equal (targ, arg))
14611 /* If PARM is `const T' and ARG is only `int', we don't have
14612 a match unless we are allowing additional qualification.
14613 If ARG is `const int' and PARM is just `T' that's OK;
14614 that binds `const int' to `T'. */
14615 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14619 /* Consider the case where ARG is `const volatile int' and
14620 PARM is `const T'. Then, T should be `volatile int'. */
14621 arg = cp_build_qualified_type_real
14622 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14623 if (arg == error_mark_node)
14626 /* Simple cases: Value already set, does match or doesn't. */
14627 if (targ != NULL_TREE && same_type_p (targ, arg))
14632 /* Make sure that ARG is not a variable-sized array. (Note
14633 that were talking about variable-sized arrays (like
14634 `int[n]'), rather than arrays of unknown size (like
14635 `int[]').) We'll get very confused by such a type since
14636 the bound of the array will not be computable in an
14637 instantiation. Besides, such types are not allowed in
14638 ISO C++, so we can do as we please here. */
14639 if (variably_modified_type_p (arg, NULL_TREE))
14642 /* Strip typedefs as in convert_template_argument. */
14643 arg = strip_typedefs (arg);
14646 /* If ARG is a parameter pack or an expansion, we cannot unify
14647 against it unless PARM is also a parameter pack. */
14648 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14649 && !template_parameter_pack_p (parm))
14652 /* If the argument deduction results is a METHOD_TYPE,
14653 then there is a problem.
14654 METHOD_TYPE doesn't map to any real C++ type the result of
14655 the deduction can not be of that type. */
14656 if (TREE_CODE (arg) == METHOD_TYPE)
14659 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14662 case TEMPLATE_PARM_INDEX:
14663 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14664 if (tparm == error_mark_node)
14667 if (TEMPLATE_PARM_LEVEL (parm)
14668 != template_decl_level (tparm))
14669 /* The PARM is not one we're trying to unify. Just check
14670 to see if it matches ARG. */
14671 return !(TREE_CODE (arg) == TREE_CODE (parm)
14672 && cp_tree_equal (parm, arg));
14674 idx = TEMPLATE_PARM_IDX (parm);
14675 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14678 return !cp_tree_equal (targ, arg);
14680 /* [temp.deduct.type] If, in the declaration of a function template
14681 with a non-type template-parameter, the non-type
14682 template-parameter is used in an expression in the function
14683 parameter-list and, if the corresponding template-argument is
14684 deduced, the template-argument type shall match the type of the
14685 template-parameter exactly, except that a template-argument
14686 deduced from an array bound may be of any integral type.
14687 The non-type parameter might use already deduced type parameters. */
14688 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14689 if (!TREE_TYPE (arg))
14690 /* Template-parameter dependent expression. Just accept it for now.
14691 It will later be processed in convert_template_argument. */
14693 else if (same_type_p (TREE_TYPE (arg), tparm))
14695 else if ((strict & UNIFY_ALLOW_INTEGER)
14696 && (TREE_CODE (tparm) == INTEGER_TYPE
14697 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14698 /* Convert the ARG to the type of PARM; the deduced non-type
14699 template argument must exactly match the types of the
14700 corresponding parameter. */
14701 arg = fold (build_nop (tparm, arg));
14702 else if (uses_template_parms (tparm))
14703 /* We haven't deduced the type of this parameter yet. Try again
14709 /* If ARG is a parameter pack or an expansion, we cannot unify
14710 against it unless PARM is also a parameter pack. */
14711 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14712 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14715 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14720 /* A pointer-to-member constant can be unified only with
14721 another constant. */
14722 if (TREE_CODE (arg) != PTRMEM_CST)
14725 /* Just unify the class member. It would be useless (and possibly
14726 wrong, depending on the strict flags) to unify also
14727 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14728 arg refer to the same variable, even if through different
14729 classes. For instance:
14731 struct A { int x; };
14734 Unification of &A::x and &B::x must succeed. */
14735 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14736 PTRMEM_CST_MEMBER (arg), strict);
14741 if (TREE_CODE (arg) != POINTER_TYPE)
14744 /* [temp.deduct.call]
14746 A can be another pointer or pointer to member type that can
14747 be converted to the deduced A via a qualification
14748 conversion (_conv.qual_).
14750 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14751 This will allow for additional cv-qualification of the
14752 pointed-to types if appropriate. */
14754 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14755 /* The derived-to-base conversion only persists through one
14756 level of pointers. */
14757 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14759 return unify (tparms, targs, TREE_TYPE (parm),
14760 TREE_TYPE (arg), strict);
14763 case REFERENCE_TYPE:
14764 if (TREE_CODE (arg) != REFERENCE_TYPE)
14766 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14767 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14770 if (TREE_CODE (arg) != ARRAY_TYPE)
14772 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14773 != (TYPE_DOMAIN (arg) == NULL_TREE))
14775 if (TYPE_DOMAIN (parm) != NULL_TREE)
14782 /* Our representation of array types uses "N - 1" as the
14783 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14784 not an integer constant. We cannot unify arbitrarily
14785 complex expressions, so we eliminate the MINUS_EXPRs
14787 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14788 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14791 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14792 parm_max = TREE_OPERAND (parm_max, 0);
14794 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14795 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14798 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14799 trying to unify the type of a variable with the type
14800 of a template parameter. For example:
14802 template <unsigned int N>
14803 void f (char (&) [N]);
14810 Here, the type of the ARG will be "int [g(i)]", and
14811 may be a SAVE_EXPR, etc. */
14812 if (TREE_CODE (arg_max) != MINUS_EXPR)
14814 arg_max = TREE_OPERAND (arg_max, 0);
14817 /* If only one of the bounds used a MINUS_EXPR, compensate
14818 by adding one to the other bound. */
14819 if (parm_cst && !arg_cst)
14820 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14824 else if (arg_cst && !parm_cst)
14825 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14830 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14833 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14834 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14841 case ENUMERAL_TYPE:
14843 if (TREE_CODE (arg) != TREE_CODE (parm))
14846 /* We have already checked cv-qualification at the top of the
14848 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14851 /* As far as unification is concerned, this wins. Later checks
14852 will invalidate it if necessary. */
14855 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14856 /* Type INTEGER_CST can come from ordinary constant template args. */
14858 while (TREE_CODE (arg) == NOP_EXPR)
14859 arg = TREE_OPERAND (arg, 0);
14861 if (TREE_CODE (arg) != INTEGER_CST)
14863 return !tree_int_cst_equal (parm, arg);
14868 if (TREE_CODE (arg) != TREE_VEC)
14870 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14872 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14873 if (unify (tparms, targs,
14874 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14882 if (TREE_CODE (arg) != TREE_CODE (parm))
14885 if (TYPE_PTRMEMFUNC_P (parm))
14887 if (!TYPE_PTRMEMFUNC_P (arg))
14890 return unify (tparms, targs,
14891 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14892 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14896 if (CLASSTYPE_TEMPLATE_INFO (parm))
14898 tree t = NULL_TREE;
14900 if (strict_in & UNIFY_ALLOW_DERIVED)
14902 /* First, we try to unify the PARM and ARG directly. */
14903 t = try_class_unification (tparms, targs,
14908 /* Fallback to the special case allowed in
14909 [temp.deduct.call]:
14911 If P is a class, and P has the form
14912 template-id, then A can be a derived class of
14913 the deduced A. Likewise, if P is a pointer to
14914 a class of the form template-id, A can be a
14915 pointer to a derived class pointed to by the
14917 t = get_template_base (tparms, targs, parm, arg);
14923 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14924 && (CLASSTYPE_TI_TEMPLATE (parm)
14925 == CLASSTYPE_TI_TEMPLATE (arg)))
14926 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14927 Then, we should unify `int' and `U'. */
14930 /* There's no chance of unification succeeding. */
14933 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14934 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14936 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14941 case FUNCTION_TYPE:
14943 unsigned int nargs;
14948 if (TREE_CODE (arg) != TREE_CODE (parm))
14951 /* CV qualifications for methods can never be deduced, they must
14952 match exactly. We need to check them explicitly here,
14953 because type_unification_real treats them as any other
14954 cv-qualified parameter. */
14955 if (TREE_CODE (parm) == METHOD_TYPE
14956 && (!check_cv_quals_for_unify
14958 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14959 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14962 if (unify (tparms, targs, TREE_TYPE (parm),
14963 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14966 nargs = list_length (TYPE_ARG_TYPES (arg));
14967 args = XALLOCAVEC (tree, nargs);
14968 for (a = TYPE_ARG_TYPES (arg), i = 0;
14969 a != NULL_TREE && a != void_list_node;
14970 a = TREE_CHAIN (a), ++i)
14971 args[i] = TREE_VALUE (a);
14974 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14975 args, nargs, 1, DEDUCE_EXACT,
14980 /* Unify a pointer to member with a pointer to member function, which
14981 deduces the type of the member as a function type. */
14982 if (TYPE_PTRMEMFUNC_P (arg))
14986 cp_cv_quals cv_quals;
14988 /* Check top-level cv qualifiers */
14989 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14992 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14993 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14996 /* Determine the type of the function we are unifying against. */
14997 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14999 build_function_type (TREE_TYPE (method_type),
15000 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
15002 /* Extract the cv-qualifiers of the member function from the
15003 implicit object parameter and place them on the function
15004 type to be restored later. */
15006 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
15007 fntype = build_qualified_type (fntype, cv_quals);
15008 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
15011 if (TREE_CODE (arg) != OFFSET_TYPE)
15013 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
15014 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
15016 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
15020 if (DECL_TEMPLATE_PARM_P (parm))
15021 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
15022 if (arg != integral_constant_value (parm))
15027 case TEMPLATE_DECL:
15028 /* Matched cases are handled by the ARG == PARM test above. */
15031 case TYPE_ARGUMENT_PACK:
15032 case NONTYPE_ARGUMENT_PACK:
15034 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
15035 tree packed_args = ARGUMENT_PACK_ARGS (arg);
15036 int i, len = TREE_VEC_LENGTH (packed_parms);
15037 int argslen = TREE_VEC_LENGTH (packed_args);
15038 int parm_variadic_p = 0;
15040 for (i = 0; i < len; ++i)
15042 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
15045 /* We can unify against something with a trailing
15047 parm_variadic_p = 1;
15049 /* Since there is something following the pack
15050 expansion, we cannot unify this template argument
15057 /* If we don't have enough arguments to satisfy the parameters
15058 (not counting the pack expression at the end), or we have
15059 too many arguments for a parameter list that doesn't end in
15060 a pack expression, we can't unify. */
15061 if (argslen < (len - parm_variadic_p)
15062 || (argslen > len && !parm_variadic_p))
15065 /* Unify all of the parameters that precede the (optional)
15066 pack expression. */
15067 for (i = 0; i < len - parm_variadic_p; ++i)
15069 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15070 TREE_VEC_ELT (packed_args, i), strict))
15074 if (parm_variadic_p)
15075 return unify_pack_expansion (tparms, targs,
15076 packed_parms, packed_args,
15077 strict, /*call_args_p=*/false,
15085 case DECLTYPE_TYPE:
15086 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
15091 /* Unification fails if we hit an error node. */
15095 gcc_assert (EXPR_P (parm));
15097 /* We must be looking at an expression. This can happen with
15101 void foo(S<I>, S<I + 2>);
15103 This is a "nondeduced context":
15107 The nondeduced contexts are:
15109 --A type that is a template-id in which one or more of
15110 the template-arguments is an expression that references
15111 a template-parameter.
15113 In these cases, we assume deduction succeeded, but don't
15114 actually infer any unifications. */
15116 if (!uses_template_parms (parm)
15117 && !template_args_equal (parm, arg))
15124 /* Note that DECL can be defined in this translation unit, if
15128 mark_definable (tree decl)
15131 DECL_NOT_REALLY_EXTERN (decl) = 1;
15132 FOR_EACH_CLONE (clone, decl)
15133 DECL_NOT_REALLY_EXTERN (clone) = 1;
15136 /* Called if RESULT is explicitly instantiated, or is a member of an
15137 explicitly instantiated class. */
15140 mark_decl_instantiated (tree result, int extern_p)
15142 SET_DECL_EXPLICIT_INSTANTIATION (result);
15144 /* If this entity has already been written out, it's too late to
15145 make any modifications. */
15146 if (TREE_ASM_WRITTEN (result))
15149 if (TREE_CODE (result) != FUNCTION_DECL)
15150 /* The TREE_PUBLIC flag for function declarations will have been
15151 set correctly by tsubst. */
15152 TREE_PUBLIC (result) = 1;
15154 /* This might have been set by an earlier implicit instantiation. */
15155 DECL_COMDAT (result) = 0;
15158 DECL_NOT_REALLY_EXTERN (result) = 0;
15161 mark_definable (result);
15162 /* Always make artificials weak. */
15163 if (DECL_ARTIFICIAL (result) && flag_weak)
15164 comdat_linkage (result);
15165 /* For WIN32 we also want to put explicit instantiations in
15166 linkonce sections. */
15167 else if (TREE_PUBLIC (result))
15168 maybe_make_one_only (result);
15171 /* If EXTERN_P, then this function will not be emitted -- unless
15172 followed by an explicit instantiation, at which point its linkage
15173 will be adjusted. If !EXTERN_P, then this function will be
15174 emitted here. In neither circumstance do we want
15175 import_export_decl to adjust the linkage. */
15176 DECL_INTERFACE_KNOWN (result) = 1;
15179 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
15180 important template arguments. If any are missing, we check whether
15181 they're important by using error_mark_node for substituting into any
15182 args that were used for partial ordering (the ones between ARGS and END)
15183 and seeing if it bubbles up. */
15186 check_undeduced_parms (tree targs, tree args, tree end)
15188 bool found = false;
15190 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
15191 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
15194 TREE_VEC_ELT (targs, i) = error_mark_node;
15198 for (; args != end; args = TREE_CHAIN (args))
15200 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
15201 if (substed == error_mark_node)
15208 /* Given two function templates PAT1 and PAT2, return:
15210 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
15211 -1 if PAT2 is more specialized than PAT1.
15212 0 if neither is more specialized.
15214 LEN indicates the number of parameters we should consider
15215 (defaulted parameters should not be considered).
15217 The 1998 std underspecified function template partial ordering, and
15218 DR214 addresses the issue. We take pairs of arguments, one from
15219 each of the templates, and deduce them against each other. One of
15220 the templates will be more specialized if all the *other*
15221 template's arguments deduce against its arguments and at least one
15222 of its arguments *does* *not* deduce against the other template's
15223 corresponding argument. Deduction is done as for class templates.
15224 The arguments used in deduction have reference and top level cv
15225 qualifiers removed. Iff both arguments were originally reference
15226 types *and* deduction succeeds in both directions, the template
15227 with the more cv-qualified argument wins for that pairing (if
15228 neither is more cv-qualified, they both are equal). Unlike regular
15229 deduction, after all the arguments have been deduced in this way,
15230 we do *not* verify the deduced template argument values can be
15231 substituted into non-deduced contexts.
15233 The logic can be a bit confusing here, because we look at deduce1 and
15234 targs1 to see if pat2 is at least as specialized, and vice versa; if we
15235 can find template arguments for pat1 to make arg1 look like arg2, that
15236 means that arg2 is at least as specialized as arg1. */
15239 more_specialized_fn (tree pat1, tree pat2, int len)
15241 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
15242 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
15243 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
15244 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
15245 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
15246 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
15247 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
15248 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
15249 tree origs1, origs2;
15250 bool lose1 = false;
15251 bool lose2 = false;
15253 /* Remove the this parameter from non-static member functions. If
15254 one is a non-static member function and the other is not a static
15255 member function, remove the first parameter from that function
15256 also. This situation occurs for operator functions where we
15257 locate both a member function (with this pointer) and non-member
15258 operator (with explicit first operand). */
15259 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
15261 len--; /* LEN is the number of significant arguments for DECL1 */
15262 args1 = TREE_CHAIN (args1);
15263 if (!DECL_STATIC_FUNCTION_P (decl2))
15264 args2 = TREE_CHAIN (args2);
15266 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
15268 args2 = TREE_CHAIN (args2);
15269 if (!DECL_STATIC_FUNCTION_P (decl1))
15272 args1 = TREE_CHAIN (args1);
15276 /* If only one is a conversion operator, they are unordered. */
15277 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
15280 /* Consider the return type for a conversion function */
15281 if (DECL_CONV_FN_P (decl1))
15283 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
15284 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
15288 processing_template_decl++;
15294 /* Stop when an ellipsis is seen. */
15295 && args1 != NULL_TREE && args2 != NULL_TREE)
15297 tree arg1 = TREE_VALUE (args1);
15298 tree arg2 = TREE_VALUE (args2);
15299 int deduce1, deduce2;
15303 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15304 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15306 /* When both arguments are pack expansions, we need only
15307 unify the patterns themselves. */
15308 arg1 = PACK_EXPANSION_PATTERN (arg1);
15309 arg2 = PACK_EXPANSION_PATTERN (arg2);
15311 /* This is the last comparison we need to do. */
15315 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15317 arg1 = TREE_TYPE (arg1);
15318 quals1 = cp_type_quals (arg1);
15321 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15323 arg2 = TREE_TYPE (arg2);
15324 quals2 = cp_type_quals (arg2);
15327 if ((quals1 < 0) != (quals2 < 0))
15329 /* Only of the args is a reference, see if we should apply
15330 array/function pointer decay to it. This is not part of
15331 DR214, but is, IMHO, consistent with the deduction rules
15332 for the function call itself, and with our earlier
15333 implementation of the underspecified partial ordering
15334 rules. (nathan). */
15337 switch (TREE_CODE (arg1))
15340 arg1 = TREE_TYPE (arg1);
15342 case FUNCTION_TYPE:
15343 arg1 = build_pointer_type (arg1);
15352 switch (TREE_CODE (arg2))
15355 arg2 = TREE_TYPE (arg2);
15357 case FUNCTION_TYPE:
15358 arg2 = build_pointer_type (arg2);
15367 arg1 = TYPE_MAIN_VARIANT (arg1);
15368 arg2 = TYPE_MAIN_VARIANT (arg2);
15370 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15372 int i, len2 = list_length (args2);
15373 tree parmvec = make_tree_vec (1);
15374 tree argvec = make_tree_vec (len2);
15377 /* Setup the parameter vector, which contains only ARG1. */
15378 TREE_VEC_ELT (parmvec, 0) = arg1;
15380 /* Setup the argument vector, which contains the remaining
15382 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15383 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15385 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15386 argvec, UNIFY_ALLOW_NONE,
15387 /*call_args_p=*/false,
15390 /* We cannot deduce in the other direction, because ARG1 is
15391 a pack expansion but ARG2 is not. */
15394 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15396 int i, len1 = list_length (args1);
15397 tree parmvec = make_tree_vec (1);
15398 tree argvec = make_tree_vec (len1);
15401 /* Setup the parameter vector, which contains only ARG1. */
15402 TREE_VEC_ELT (parmvec, 0) = arg2;
15404 /* Setup the argument vector, which contains the remaining
15406 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15407 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15409 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15410 argvec, UNIFY_ALLOW_NONE,
15411 /*call_args_p=*/false,
15414 /* We cannot deduce in the other direction, because ARG2 is
15415 a pack expansion but ARG1 is not.*/
15421 /* The normal case, where neither argument is a pack
15423 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15424 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15427 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15428 arg2, then arg2 is not as specialized as arg1. */
15434 /* "If, for a given type, deduction succeeds in both directions
15435 (i.e., the types are identical after the transformations above)
15436 and if the type from the argument template is more cv-qualified
15437 than the type from the parameter template (as described above)
15438 that type is considered to be more specialized than the other. If
15439 neither type is more cv-qualified than the other then neither type
15440 is more specialized than the other."
15442 We check same_type_p explicitly because deduction can also succeed
15443 in both directions when there is a nondeduced context. */
15444 if (deduce1 && deduce2
15445 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0
15446 && same_type_p (arg1, arg2))
15448 if ((quals1 & quals2) == quals2)
15450 if ((quals1 & quals2) == quals1)
15454 if (lose1 && lose2)
15455 /* We've failed to deduce something in either direction.
15456 These must be unordered. */
15459 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15460 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15461 /* We have already processed all of the arguments in our
15462 handing of the pack expansion type. */
15465 args1 = TREE_CHAIN (args1);
15466 args2 = TREE_CHAIN (args2);
15469 /* "In most cases, all template parameters must have values in order for
15470 deduction to succeed, but for partial ordering purposes a template
15471 parameter may remain without a value provided it is not used in the
15472 types being used for partial ordering."
15474 Thus, if we are missing any of the targs1 we need to substitute into
15475 origs1, then pat2 is not as specialized as pat1. This can happen when
15476 there is a nondeduced context. */
15477 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15479 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15482 processing_template_decl--;
15484 /* All things being equal, if the next argument is a pack expansion
15485 for one function but not for the other, prefer the
15486 non-variadic function. FIXME this is bogus; see c++/41958. */
15488 && args1 && TREE_VALUE (args1)
15489 && args2 && TREE_VALUE (args2))
15491 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
15492 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
15495 if (lose1 == lose2)
15503 /* Determine which of two partial specializations is more specialized.
15505 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15506 to the first partial specialization. The TREE_VALUE is the
15507 innermost set of template parameters for the partial
15508 specialization. PAT2 is similar, but for the second template.
15510 Return 1 if the first partial specialization is more specialized;
15511 -1 if the second is more specialized; 0 if neither is more
15514 See [temp.class.order] for information about determining which of
15515 two templates is more specialized. */
15518 more_specialized_class (tree pat1, tree pat2)
15523 bool any_deductions = false;
15525 tmpl1 = TREE_TYPE (pat1);
15526 tmpl2 = TREE_TYPE (pat2);
15528 /* Just like what happens for functions, if we are ordering between
15529 different class template specializations, we may encounter dependent
15530 types in the arguments, and we need our dependency check functions
15531 to behave correctly. */
15532 ++processing_template_decl;
15533 targs = get_class_bindings (TREE_VALUE (pat1),
15534 CLASSTYPE_TI_ARGS (tmpl1),
15535 CLASSTYPE_TI_ARGS (tmpl2));
15539 any_deductions = true;
15542 targs = get_class_bindings (TREE_VALUE (pat2),
15543 CLASSTYPE_TI_ARGS (tmpl2),
15544 CLASSTYPE_TI_ARGS (tmpl1));
15548 any_deductions = true;
15550 --processing_template_decl;
15552 /* In the case of a tie where at least one of the class templates
15553 has a parameter pack at the end, the template with the most
15554 non-packed parameters wins. */
15557 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15558 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15560 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15561 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15562 int len1 = TREE_VEC_LENGTH (args1);
15563 int len2 = TREE_VEC_LENGTH (args2);
15565 /* We don't count the pack expansion at the end. */
15566 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15568 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15573 else if (len1 < len2)
15580 /* Return the template arguments that will produce the function signature
15581 DECL from the function template FN, with the explicit template
15582 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15583 also match. Return NULL_TREE if no satisfactory arguments could be
15587 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15589 int ntparms = DECL_NTPARMS (fn);
15590 tree targs = make_tree_vec (ntparms);
15592 tree decl_arg_types;
15594 unsigned int nargs, ix;
15597 /* Substitute the explicit template arguments into the type of DECL.
15598 The call to fn_type_unification will handle substitution into the
15600 decl_type = TREE_TYPE (decl);
15601 if (explicit_args && uses_template_parms (decl_type))
15604 tree converted_args;
15606 if (DECL_TEMPLATE_INFO (decl))
15607 tmpl = DECL_TI_TEMPLATE (decl);
15609 /* We can get here for some invalid specializations. */
15613 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15614 explicit_args, NULL_TREE,
15616 /*require_all_args=*/false,
15617 /*use_default_args=*/false);
15618 if (converted_args == error_mark_node)
15621 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15622 if (decl_type == error_mark_node)
15626 /* Never do unification on the 'this' parameter. */
15627 decl_arg_types = skip_artificial_parms_for (decl,
15628 TYPE_ARG_TYPES (decl_type));
15630 nargs = list_length (decl_arg_types);
15631 args = XALLOCAVEC (tree, nargs);
15632 for (arg = decl_arg_types, ix = 0;
15633 arg != NULL_TREE && arg != void_list_node;
15634 arg = TREE_CHAIN (arg), ++ix)
15635 args[ix] = TREE_VALUE (arg);
15637 if (fn_type_unification (fn, explicit_args, targs,
15639 (check_rettype || DECL_CONV_FN_P (fn)
15640 ? TREE_TYPE (decl_type) : NULL_TREE),
15641 DEDUCE_EXACT, LOOKUP_NORMAL))
15647 /* Return the innermost template arguments that, when applied to a
15648 template specialization whose innermost template parameters are
15649 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15652 For example, suppose we have:
15654 template <class T, class U> struct S {};
15655 template <class T> struct S<T*, int> {};
15657 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15658 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15659 int}. The resulting vector will be {double}, indicating that `T'
15660 is bound to `double'. */
15663 get_class_bindings (tree tparms, tree spec_args, tree args)
15665 int i, ntparms = TREE_VEC_LENGTH (tparms);
15667 tree innermost_deduced_args;
15669 innermost_deduced_args = make_tree_vec (ntparms);
15670 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15672 deduced_args = copy_node (args);
15673 SET_TMPL_ARGS_LEVEL (deduced_args,
15674 TMPL_ARGS_DEPTH (deduced_args),
15675 innermost_deduced_args);
15678 deduced_args = innermost_deduced_args;
15680 if (unify (tparms, deduced_args,
15681 INNERMOST_TEMPLATE_ARGS (spec_args),
15682 INNERMOST_TEMPLATE_ARGS (args),
15686 for (i = 0; i < ntparms; ++i)
15687 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15690 /* Verify that nondeduced template arguments agree with the type
15691 obtained from argument deduction.
15695 struct A { typedef int X; };
15696 template <class T, class U> struct C {};
15697 template <class T> struct C<T, typename T::X> {};
15699 Then with the instantiation `C<A, int>', we can deduce that
15700 `T' is `A' but unify () does not check whether `typename T::X'
15702 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15703 if (spec_args == error_mark_node
15704 /* We only need to check the innermost arguments; the other
15705 arguments will always agree. */
15706 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15707 INNERMOST_TEMPLATE_ARGS (args)))
15710 /* Now that we have bindings for all of the template arguments,
15711 ensure that the arguments deduced for the template template
15712 parameters have compatible template parameter lists. See the use
15713 of template_template_parm_bindings_ok_p in fn_type_unification
15714 for more information. */
15715 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15718 return deduced_args;
15721 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15722 Return the TREE_LIST node with the most specialized template, if
15723 any. If there is no most specialized template, the error_mark_node
15726 Note that this function does not look at, or modify, the
15727 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15728 returned is one of the elements of INSTANTIATIONS, callers may
15729 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15730 and retrieve it from the value returned. */
15733 most_specialized_instantiation (tree templates)
15737 ++processing_template_decl;
15740 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15744 if (get_bindings (TREE_VALUE (champ),
15745 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15746 NULL_TREE, /*check_ret=*/false))
15749 if (get_bindings (TREE_VALUE (fn),
15750 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15751 NULL_TREE, /*check_ret=*/false))
15758 /* Equally specialized, move to next function. If there
15759 is no next function, nothing's most specialized. */
15760 fn = TREE_CHAIN (fn);
15768 /* Now verify that champ is better than everything earlier in the
15769 instantiation list. */
15770 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15771 if (get_bindings (TREE_VALUE (champ),
15772 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15773 NULL_TREE, /*check_ret=*/false)
15774 || !get_bindings (TREE_VALUE (fn),
15775 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15776 NULL_TREE, /*check_ret=*/false))
15782 processing_template_decl--;
15785 return error_mark_node;
15790 /* If DECL is a specialization of some template, return the most
15791 general such template. Otherwise, returns NULL_TREE.
15793 For example, given:
15795 template <class T> struct S { template <class U> void f(U); };
15797 if TMPL is `template <class U> void S<int>::f(U)' this will return
15798 the full template. This function will not trace past partial
15799 specializations, however. For example, given in addition:
15801 template <class T> struct S<T*> { template <class U> void f(U); };
15803 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15804 `template <class T> template <class U> S<T*>::f(U)'. */
15807 most_general_template (tree decl)
15809 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15810 an immediate specialization. */
15811 if (TREE_CODE (decl) == FUNCTION_DECL)
15813 if (DECL_TEMPLATE_INFO (decl)) {
15814 decl = DECL_TI_TEMPLATE (decl);
15816 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15817 template friend. */
15818 if (TREE_CODE (decl) != TEMPLATE_DECL)
15824 /* Look for more and more general templates. */
15825 while (DECL_TEMPLATE_INFO (decl))
15827 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15828 (See cp-tree.h for details.) */
15829 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15832 if (CLASS_TYPE_P (TREE_TYPE (decl))
15833 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15836 /* Stop if we run into an explicitly specialized class template. */
15837 if (!DECL_NAMESPACE_SCOPE_P (decl)
15838 && DECL_CONTEXT (decl)
15839 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15842 decl = DECL_TI_TEMPLATE (decl);
15848 /* Return the most specialized of the class template partial
15849 specializations of TMPL which can produce TYPE, a specialization of
15850 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15851 a _TYPE node corresponding to the partial specialization, while the
15852 TREE_PURPOSE is the set of template arguments that must be
15853 substituted into the TREE_TYPE in order to generate TYPE.
15855 If the choice of partial specialization is ambiguous, a diagnostic
15856 is issued, and the error_mark_node is returned. If there are no
15857 partial specializations of TMPL matching TYPE, then NULL_TREE is
15861 most_specialized_class (tree type, tree tmpl)
15863 tree list = NULL_TREE;
15869 tree outer_args = NULL_TREE;
15871 tmpl = most_general_template (tmpl);
15872 args = CLASSTYPE_TI_ARGS (type);
15874 /* For determining which partial specialization to use, only the
15875 innermost args are interesting. */
15876 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15878 outer_args = strip_innermost_template_args (args, 1);
15879 args = INNERMOST_TEMPLATE_ARGS (args);
15882 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15884 tree partial_spec_args;
15886 tree parms = TREE_VALUE (t);
15888 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15893 ++processing_template_decl;
15895 /* Discard the outer levels of args, and then substitute in the
15896 template args from the enclosing class. */
15897 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15898 partial_spec_args = tsubst_template_args
15899 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15901 /* PARMS already refers to just the innermost parms, but the
15902 template parms in partial_spec_args had their levels lowered
15903 by tsubst, so we need to do the same for the parm list. We
15904 can't just tsubst the TREE_VEC itself, as tsubst wants to
15905 treat a TREE_VEC as an argument vector. */
15906 parms = copy_node (parms);
15907 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15908 TREE_VEC_ELT (parms, i) =
15909 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15911 --processing_template_decl;
15913 spec_args = get_class_bindings (parms,
15919 spec_args = add_to_template_args (outer_args, spec_args);
15920 list = tree_cons (spec_args, TREE_VALUE (t), list);
15921 TREE_TYPE (list) = TREE_TYPE (t);
15928 ambiguous_p = false;
15931 t = TREE_CHAIN (t);
15932 for (; t; t = TREE_CHAIN (t))
15934 fate = more_specialized_class (champ, t);
15941 t = TREE_CHAIN (t);
15944 ambiguous_p = true;
15953 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15955 fate = more_specialized_class (champ, t);
15958 ambiguous_p = true;
15966 char *spaces = NULL;
15967 error ("ambiguous class template instantiation for %q#T", type);
15968 str = TREE_CHAIN (list) ? _("candidates are:") : _("candidate is:");
15969 for (t = list; t; t = TREE_CHAIN (t))
15971 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
15972 spaces = spaces ? spaces : get_spaces (str);
15975 return error_mark_node;
15981 /* Explicitly instantiate DECL. */
15984 do_decl_instantiation (tree decl, tree storage)
15986 tree result = NULL_TREE;
15989 if (!decl || decl == error_mark_node)
15990 /* An error occurred, for which grokdeclarator has already issued
15991 an appropriate message. */
15993 else if (! DECL_LANG_SPECIFIC (decl))
15995 error ("explicit instantiation of non-template %q#D", decl);
15998 else if (TREE_CODE (decl) == VAR_DECL)
16000 /* There is an asymmetry here in the way VAR_DECLs and
16001 FUNCTION_DECLs are handled by grokdeclarator. In the case of
16002 the latter, the DECL we get back will be marked as a
16003 template instantiation, and the appropriate
16004 DECL_TEMPLATE_INFO will be set up. This does not happen for
16005 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
16006 should handle VAR_DECLs as it currently handles
16008 if (!DECL_CLASS_SCOPE_P (decl))
16010 error ("%qD is not a static data member of a class template", decl);
16013 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
16014 if (!result || TREE_CODE (result) != VAR_DECL)
16016 error ("no matching template for %qD found", decl);
16019 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
16021 error ("type %qT for explicit instantiation %qD does not match "
16022 "declared type %qT", TREE_TYPE (result), decl,
16027 else if (TREE_CODE (decl) != FUNCTION_DECL)
16029 error ("explicit instantiation of %q#D", decl);
16035 /* Check for various error cases. Note that if the explicit
16036 instantiation is valid the RESULT will currently be marked as an
16037 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
16038 until we get here. */
16040 if (DECL_TEMPLATE_SPECIALIZATION (result))
16042 /* DR 259 [temp.spec].
16044 Both an explicit instantiation and a declaration of an explicit
16045 specialization shall not appear in a program unless the explicit
16046 instantiation follows a declaration of the explicit specialization.
16048 For a given set of template parameters, if an explicit
16049 instantiation of a template appears after a declaration of an
16050 explicit specialization for that template, the explicit
16051 instantiation has no effect. */
16054 else if (DECL_EXPLICIT_INSTANTIATION (result))
16058 No program shall explicitly instantiate any template more
16061 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16062 the first instantiation was `extern' and the second is not,
16063 and EXTERN_P for the opposite case. */
16064 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16065 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16066 /* If an "extern" explicit instantiation follows an ordinary
16067 explicit instantiation, the template is instantiated. */
16071 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16073 error ("no matching template for %qD found", result);
16076 else if (!DECL_TEMPLATE_INFO (result))
16078 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16082 if (storage == NULL_TREE)
16084 else if (storage == ridpointers[(int) RID_EXTERN])
16086 if (!in_system_header && (cxx_dialect == cxx98))
16087 pedwarn (input_location, OPT_pedantic,
16088 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16093 error ("storage class %qD applied to template instantiation", storage);
16095 check_explicit_instantiation_namespace (result);
16096 mark_decl_instantiated (result, extern_p);
16098 instantiate_decl (result, /*defer_ok=*/1,
16099 /*expl_inst_class_mem_p=*/false);
16103 mark_class_instantiated (tree t, int extern_p)
16105 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16106 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16107 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16108 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16111 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16112 rest_of_type_compilation (t, 1);
16116 /* Called from do_type_instantiation through binding_table_foreach to
16117 do recursive instantiation for the type bound in ENTRY. */
16119 bt_instantiate_type_proc (binding_entry entry, void *data)
16121 tree storage = *(tree *) data;
16123 if (MAYBE_CLASS_TYPE_P (entry->type)
16124 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16125 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16128 /* Called from do_type_instantiation to instantiate a member
16129 (a member function or a static member variable) of an
16130 explicitly instantiated class template. */
16132 instantiate_class_member (tree decl, int extern_p)
16134 mark_decl_instantiated (decl, extern_p);
16136 instantiate_decl (decl, /*defer_ok=*/1,
16137 /*expl_inst_class_mem_p=*/true);
16140 /* Perform an explicit instantiation of template class T. STORAGE, if
16141 non-null, is the RID for extern, inline or static. COMPLAIN is
16142 nonzero if this is called from the parser, zero if called recursively,
16143 since the standard is unclear (as detailed below). */
16146 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16151 int previous_instantiation_extern_p = 0;
16153 if (TREE_CODE (t) == TYPE_DECL)
16156 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16158 error ("explicit instantiation of non-template type %qT", t);
16164 if (!COMPLETE_TYPE_P (t))
16166 if (complain & tf_error)
16167 error ("explicit instantiation of %q#T before definition of template",
16172 if (storage != NULL_TREE)
16174 if (!in_system_header)
16176 if (storage == ridpointers[(int) RID_EXTERN])
16178 if (cxx_dialect == cxx98)
16179 pedwarn (input_location, OPT_pedantic,
16180 "ISO C++ 1998 forbids the use of %<extern%> on "
16181 "explicit instantiations");
16184 pedwarn (input_location, OPT_pedantic,
16185 "ISO C++ forbids the use of %qE"
16186 " on explicit instantiations", storage);
16189 if (storage == ridpointers[(int) RID_INLINE])
16191 else if (storage == ridpointers[(int) RID_EXTERN])
16193 else if (storage == ridpointers[(int) RID_STATIC])
16197 error ("storage class %qD applied to template instantiation",
16203 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
16205 /* DR 259 [temp.spec].
16207 Both an explicit instantiation and a declaration of an explicit
16208 specialization shall not appear in a program unless the explicit
16209 instantiation follows a declaration of the explicit specialization.
16211 For a given set of template parameters, if an explicit
16212 instantiation of a template appears after a declaration of an
16213 explicit specialization for that template, the explicit
16214 instantiation has no effect. */
16217 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
16221 No program shall explicitly instantiate any template more
16224 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
16225 instantiation was `extern'. If EXTERN_P then the second is.
16226 These cases are OK. */
16227 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
16229 if (!previous_instantiation_extern_p && !extern_p
16230 && (complain & tf_error))
16231 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
16233 /* If we've already instantiated the template, just return now. */
16234 if (!CLASSTYPE_INTERFACE_ONLY (t))
16238 check_explicit_instantiation_namespace (TYPE_NAME (t));
16239 mark_class_instantiated (t, extern_p);
16247 /* In contrast to implicit instantiation, where only the
16248 declarations, and not the definitions, of members are
16249 instantiated, we have here:
16253 The explicit instantiation of a class template specialization
16254 implies the instantiation of all of its members not
16255 previously explicitly specialized in the translation unit
16256 containing the explicit instantiation.
16258 Of course, we can't instantiate member template classes, since
16259 we don't have any arguments for them. Note that the standard
16260 is unclear on whether the instantiation of the members are
16261 *explicit* instantiations or not. However, the most natural
16262 interpretation is that it should be an explicit instantiation. */
16265 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
16266 if (TREE_CODE (tmp) == FUNCTION_DECL
16267 && DECL_TEMPLATE_INSTANTIATION (tmp))
16268 instantiate_class_member (tmp, extern_p);
16270 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
16271 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
16272 instantiate_class_member (tmp, extern_p);
16274 if (CLASSTYPE_NESTED_UTDS (t))
16275 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
16276 bt_instantiate_type_proc, &storage);
16280 /* Given a function DECL, which is a specialization of TMPL, modify
16281 DECL to be a re-instantiation of TMPL with the same template
16282 arguments. TMPL should be the template into which tsubst'ing
16283 should occur for DECL, not the most general template.
16285 One reason for doing this is a scenario like this:
16288 void f(const T&, int i);
16290 void g() { f(3, 7); }
16293 void f(const T& t, const int i) { }
16295 Note that when the template is first instantiated, with
16296 instantiate_template, the resulting DECL will have no name for the
16297 first parameter, and the wrong type for the second. So, when we go
16298 to instantiate the DECL, we regenerate it. */
16301 regenerate_decl_from_template (tree decl, tree tmpl)
16303 /* The arguments used to instantiate DECL, from the most general
16308 args = DECL_TI_ARGS (decl);
16309 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
16311 /* Make sure that we can see identifiers, and compute access
16313 push_access_scope (decl);
16315 if (TREE_CODE (decl) == FUNCTION_DECL)
16323 args_depth = TMPL_ARGS_DEPTH (args);
16324 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16325 if (args_depth > parms_depth)
16326 args = get_innermost_template_args (args, parms_depth);
16328 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16329 args, tf_error, NULL_TREE);
16331 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16334 /* Merge parameter declarations. */
16335 decl_parm = skip_artificial_parms_for (decl,
16336 DECL_ARGUMENTS (decl));
16338 = skip_artificial_parms_for (code_pattern,
16339 DECL_ARGUMENTS (code_pattern));
16340 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16345 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16346 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16347 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16349 parm_type = type_decays_to (parm_type);
16350 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16351 TREE_TYPE (decl_parm) = parm_type;
16352 attributes = DECL_ATTRIBUTES (pattern_parm);
16353 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16355 DECL_ATTRIBUTES (decl_parm) = attributes;
16356 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16358 decl_parm = TREE_CHAIN (decl_parm);
16359 pattern_parm = TREE_CHAIN (pattern_parm);
16361 /* Merge any parameters that match with the function parameter
16363 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16366 tree expanded_types;
16367 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16368 the parameters in this function parameter pack. */
16369 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16370 args, tf_error, NULL_TREE);
16371 len = TREE_VEC_LENGTH (expanded_types);
16372 for (i = 0; i < len; i++)
16377 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16378 /* Rename the parameter to include the index. */
16379 DECL_NAME (decl_parm) =
16380 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16381 parm_type = TREE_VEC_ELT (expanded_types, i);
16382 parm_type = type_decays_to (parm_type);
16383 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16384 TREE_TYPE (decl_parm) = parm_type;
16385 attributes = DECL_ATTRIBUTES (pattern_parm);
16386 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16388 DECL_ATTRIBUTES (decl_parm) = attributes;
16389 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16391 decl_parm = TREE_CHAIN (decl_parm);
16394 /* Merge additional specifiers from the CODE_PATTERN. */
16395 if (DECL_DECLARED_INLINE_P (code_pattern)
16396 && !DECL_DECLARED_INLINE_P (decl))
16397 DECL_DECLARED_INLINE_P (decl) = 1;
16399 else if (TREE_CODE (decl) == VAR_DECL)
16400 DECL_INITIAL (decl) =
16401 tsubst_expr (DECL_INITIAL (code_pattern), args,
16402 tf_error, DECL_TI_TEMPLATE (decl),
16403 /*integral_constant_expression_p=*/false);
16405 gcc_unreachable ();
16407 pop_access_scope (decl);
16410 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16411 substituted to get DECL. */
16414 template_for_substitution (tree decl)
16416 tree tmpl = DECL_TI_TEMPLATE (decl);
16418 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16419 for the instantiation. This is not always the most general
16420 template. Consider, for example:
16423 struct S { template <class U> void f();
16424 template <> void f<int>(); };
16426 and an instantiation of S<double>::f<int>. We want TD to be the
16427 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16428 while (/* An instantiation cannot have a definition, so we need a
16429 more general template. */
16430 DECL_TEMPLATE_INSTANTIATION (tmpl)
16431 /* We must also deal with friend templates. Given:
16433 template <class T> struct S {
16434 template <class U> friend void f() {};
16437 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16438 so far as the language is concerned, but that's still
16439 where we get the pattern for the instantiation from. On
16440 other hand, if the definition comes outside the class, say:
16442 template <class T> struct S {
16443 template <class U> friend void f();
16445 template <class U> friend void f() {}
16447 we don't need to look any further. That's what the check for
16448 DECL_INITIAL is for. */
16449 || (TREE_CODE (decl) == FUNCTION_DECL
16450 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16451 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16453 /* The present template, TD, should not be a definition. If it
16454 were a definition, we should be using it! Note that we
16455 cannot restructure the loop to just keep going until we find
16456 a template with a definition, since that might go too far if
16457 a specialization was declared, but not defined. */
16458 gcc_assert (TREE_CODE (decl) != VAR_DECL
16459 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16461 /* Fetch the more general template. */
16462 tmpl = DECL_TI_TEMPLATE (tmpl);
16468 /* Returns true if we need to instantiate this template instance even if we
16469 know we aren't going to emit it.. */
16472 always_instantiate_p (tree decl)
16474 /* We always instantiate inline functions so that we can inline them. An
16475 explicit instantiation declaration prohibits implicit instantiation of
16476 non-inline functions. With high levels of optimization, we would
16477 normally inline non-inline functions -- but we're not allowed to do
16478 that for "extern template" functions. Therefore, we check
16479 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16480 return ((TREE_CODE (decl) == FUNCTION_DECL
16481 && DECL_DECLARED_INLINE_P (decl))
16482 /* And we need to instantiate static data members so that
16483 their initializers are available in integral constant
16485 || (TREE_CODE (decl) == VAR_DECL
16486 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16489 /* Produce the definition of D, a _DECL generated from a template. If
16490 DEFER_OK is nonzero, then we don't have to actually do the
16491 instantiation now; we just have to do it sometime. Normally it is
16492 an error if this is an explicit instantiation but D is undefined.
16493 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16494 explicitly instantiated class template. */
16497 instantiate_decl (tree d, int defer_ok,
16498 bool expl_inst_class_mem_p)
16500 tree tmpl = DECL_TI_TEMPLATE (d);
16507 bool pattern_defined;
16509 location_t saved_loc = input_location;
16512 /* This function should only be used to instantiate templates for
16513 functions and static member variables. */
16514 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16515 || TREE_CODE (d) == VAR_DECL);
16517 /* Variables are never deferred; if instantiation is required, they
16518 are instantiated right away. That allows for better code in the
16519 case that an expression refers to the value of the variable --
16520 if the variable has a constant value the referring expression can
16521 take advantage of that fact. */
16522 if (TREE_CODE (d) == VAR_DECL)
16525 /* Don't instantiate cloned functions. Instead, instantiate the
16526 functions they cloned. */
16527 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16528 d = DECL_CLONED_FUNCTION (d);
16530 if (DECL_TEMPLATE_INSTANTIATED (d)
16531 || DECL_TEMPLATE_SPECIALIZATION (d))
16532 /* D has already been instantiated or explicitly specialized, so
16533 there's nothing for us to do here.
16535 It might seem reasonable to check whether or not D is an explicit
16536 instantiation, and, if so, stop here. But when an explicit
16537 instantiation is deferred until the end of the compilation,
16538 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16539 the instantiation. */
16542 /* Check to see whether we know that this template will be
16543 instantiated in some other file, as with "extern template"
16545 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16547 /* In general, we do not instantiate such templates. */
16548 if (external_p && !always_instantiate_p (d))
16551 gen_tmpl = most_general_template (tmpl);
16552 gen_args = DECL_TI_ARGS (d);
16554 if (tmpl != gen_tmpl)
16555 /* We should already have the extra args. */
16556 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16557 == TMPL_ARGS_DEPTH (gen_args));
16558 /* And what's in the hash table should match D. */
16559 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16560 || spec == NULL_TREE);
16562 /* This needs to happen before any tsubsting. */
16563 if (! push_tinst_level (d))
16566 timevar_push (TV_PARSE);
16568 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16569 for the instantiation. */
16570 td = template_for_substitution (d);
16571 code_pattern = DECL_TEMPLATE_RESULT (td);
16573 /* We should never be trying to instantiate a member of a class
16574 template or partial specialization. */
16575 gcc_assert (d != code_pattern);
16577 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16578 || DECL_TEMPLATE_SPECIALIZATION (td))
16579 /* In the case of a friend template whose definition is provided
16580 outside the class, we may have too many arguments. Drop the
16581 ones we don't need. The same is true for specializations. */
16582 args = get_innermost_template_args
16583 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16587 if (TREE_CODE (d) == FUNCTION_DECL)
16588 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16590 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16592 /* We may be in the middle of deferred access check. Disable it now. */
16593 push_deferring_access_checks (dk_no_deferred);
16595 /* Unless an explicit instantiation directive has already determined
16596 the linkage of D, remember that a definition is available for
16598 if (pattern_defined
16599 && !DECL_INTERFACE_KNOWN (d)
16600 && !DECL_NOT_REALLY_EXTERN (d))
16601 mark_definable (d);
16603 input_location = DECL_SOURCE_LOCATION (d);
16605 /* If D is a member of an explicitly instantiated class template,
16606 and no definition is available, treat it like an implicit
16608 if (!pattern_defined && expl_inst_class_mem_p
16609 && DECL_EXPLICIT_INSTANTIATION (d))
16611 DECL_NOT_REALLY_EXTERN (d) = 0;
16612 DECL_INTERFACE_KNOWN (d) = 0;
16613 SET_DECL_IMPLICIT_INSTANTIATION (d);
16616 /* Recheck the substitutions to obtain any warning messages
16617 about ignoring cv qualifiers. Don't do this for artificial decls,
16618 as it breaks the context-sensitive substitution for lambda op(). */
16619 if (!defer_ok && !DECL_ARTIFICIAL (d))
16621 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16622 tree type = TREE_TYPE (gen);
16624 /* Make sure that we can see identifiers, and compute access
16625 correctly. D is already the target FUNCTION_DECL with the
16627 push_access_scope (d);
16629 if (TREE_CODE (gen) == FUNCTION_DECL)
16631 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16632 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16634 /* Don't simply tsubst the function type, as that will give
16635 duplicate warnings about poor parameter qualifications.
16636 The function arguments are the same as the decl_arguments
16637 without the top level cv qualifiers. */
16638 type = TREE_TYPE (type);
16640 tsubst (type, gen_args, tf_warning_or_error, d);
16642 pop_access_scope (d);
16645 /* Defer all other templates, unless we have been explicitly
16646 forbidden from doing so. */
16647 if (/* If there is no definition, we cannot instantiate the
16650 /* If it's OK to postpone instantiation, do so. */
16652 /* If this is a static data member that will be defined
16653 elsewhere, we don't want to instantiate the entire data
16654 member, but we do want to instantiate the initializer so that
16655 we can substitute that elsewhere. */
16656 || (external_p && TREE_CODE (d) == VAR_DECL))
16658 /* The definition of the static data member is now required so
16659 we must substitute the initializer. */
16660 if (TREE_CODE (d) == VAR_DECL
16661 && !DECL_INITIAL (d)
16662 && DECL_INITIAL (code_pattern))
16667 ns = decl_namespace_context (d);
16668 push_nested_namespace (ns);
16669 push_nested_class (DECL_CONTEXT (d));
16670 init = tsubst_expr (DECL_INITIAL (code_pattern),
16672 tf_warning_or_error, NULL_TREE,
16673 /*integral_constant_expression_p=*/false);
16674 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16675 /*asmspec_tree=*/NULL_TREE,
16676 LOOKUP_ONLYCONVERTING);
16677 pop_nested_class ();
16678 pop_nested_namespace (ns);
16681 /* We restore the source position here because it's used by
16682 add_pending_template. */
16683 input_location = saved_loc;
16685 if (at_eof && !pattern_defined
16686 && DECL_EXPLICIT_INSTANTIATION (d)
16687 && DECL_NOT_REALLY_EXTERN (d))
16690 The definition of a non-exported function template, a
16691 non-exported member function template, or a non-exported
16692 member function or static data member of a class template
16693 shall be present in every translation unit in which it is
16694 explicitly instantiated. */
16695 permerror (input_location, "explicit instantiation of %qD "
16696 "but no definition available", d);
16698 /* ??? Historically, we have instantiated inline functions, even
16699 when marked as "extern template". */
16700 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16701 add_pending_template (d);
16704 /* Tell the repository that D is available in this translation unit
16705 -- and see if it is supposed to be instantiated here. */
16706 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16708 /* In a PCH file, despite the fact that the repository hasn't
16709 requested instantiation in the PCH it is still possible that
16710 an instantiation will be required in a file that includes the
16713 add_pending_template (d);
16714 /* Instantiate inline functions so that the inliner can do its
16715 job, even though we'll not be emitting a copy of this
16717 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16721 need_push = !cfun || !global_bindings_p ();
16723 push_to_top_level ();
16725 /* Mark D as instantiated so that recursive calls to
16726 instantiate_decl do not try to instantiate it again. */
16727 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16729 /* Regenerate the declaration in case the template has been modified
16730 by a subsequent redeclaration. */
16731 regenerate_decl_from_template (d, td);
16733 /* We already set the file and line above. Reset them now in case
16734 they changed as a result of calling regenerate_decl_from_template. */
16735 input_location = DECL_SOURCE_LOCATION (d);
16737 if (TREE_CODE (d) == VAR_DECL)
16741 /* Clear out DECL_RTL; whatever was there before may not be right
16742 since we've reset the type of the declaration. */
16743 SET_DECL_RTL (d, NULL_RTX);
16744 DECL_IN_AGGR_P (d) = 0;
16746 /* The initializer is placed in DECL_INITIAL by
16747 regenerate_decl_from_template. Pull it out so that
16748 cp_finish_decl can process it. */
16749 init = DECL_INITIAL (d);
16750 DECL_INITIAL (d) = NULL_TREE;
16751 DECL_INITIALIZED_P (d) = 0;
16753 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16754 initializer. That function will defer actual emission until
16755 we have a chance to determine linkage. */
16756 DECL_EXTERNAL (d) = 0;
16758 /* Enter the scope of D so that access-checking works correctly. */
16759 push_nested_class (DECL_CONTEXT (d));
16760 cp_finish_decl (d, init, false, NULL_TREE, 0);
16761 pop_nested_class ();
16763 else if (TREE_CODE (d) == FUNCTION_DECL)
16765 htab_t saved_local_specializations;
16770 /* Save away the current list, in case we are instantiating one
16771 template from within the body of another. */
16772 saved_local_specializations = local_specializations;
16774 /* Set up the list of local specializations. */
16775 local_specializations = htab_create (37,
16776 hash_local_specialization,
16777 eq_local_specializations,
16780 /* Set up context. */
16781 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16783 /* Create substitution entries for the parameters. */
16784 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16785 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16786 spec_parm = DECL_ARGUMENTS (d);
16787 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16789 register_local_specialization (spec_parm, tmpl_parm);
16790 spec_parm = skip_artificial_parms_for (d, spec_parm);
16791 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16793 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16795 register_local_specialization (spec_parm, tmpl_parm);
16796 tmpl_parm = TREE_CHAIN (tmpl_parm);
16797 spec_parm = TREE_CHAIN (spec_parm);
16799 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16801 /* Register the (value) argument pack as a specialization of
16802 TMPL_PARM, then move on. */
16803 tree argpack = make_fnparm_pack (spec_parm);
16804 register_local_specialization (argpack, tmpl_parm);
16805 tmpl_parm = TREE_CHAIN (tmpl_parm);
16806 spec_parm = NULL_TREE;
16808 gcc_assert (!spec_parm);
16810 /* Substitute into the body of the function. */
16811 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16812 tf_warning_or_error, tmpl,
16813 /*integral_constant_expression_p=*/false);
16815 /* Set the current input_location to the end of the function
16816 so that finish_function knows where we are. */
16817 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
16819 /* We don't need the local specializations any more. */
16820 htab_delete (local_specializations);
16821 local_specializations = saved_local_specializations;
16823 /* Finish the function. */
16824 d = finish_function (0);
16825 expand_or_defer_fn (d);
16828 /* We're not deferring instantiation any more. */
16829 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16832 pop_from_top_level ();
16835 input_location = saved_loc;
16836 pop_deferring_access_checks ();
16837 pop_tinst_level ();
16839 timevar_pop (TV_PARSE);
16844 /* Run through the list of templates that we wish we could
16845 instantiate, and instantiate any we can. RETRIES is the
16846 number of times we retry pending template instantiation. */
16849 instantiate_pending_templates (int retries)
16852 location_t saved_loc = input_location;
16854 /* Instantiating templates may trigger vtable generation. This in turn
16855 may require further template instantiations. We place a limit here
16856 to avoid infinite loop. */
16857 if (pending_templates && retries >= max_tinst_depth)
16859 tree decl = pending_templates->tinst->decl;
16861 error ("template instantiation depth exceeds maximum of %d"
16862 " instantiating %q+D, possibly from virtual table generation"
16863 " (use -ftemplate-depth= to increase the maximum)",
16864 max_tinst_depth, decl);
16865 if (TREE_CODE (decl) == FUNCTION_DECL)
16866 /* Pretend that we defined it. */
16867 DECL_INITIAL (decl) = error_mark_node;
16873 struct pending_template **t = &pending_templates;
16874 struct pending_template *last = NULL;
16878 tree instantiation = reopen_tinst_level ((*t)->tinst);
16879 bool complete = false;
16881 if (TYPE_P (instantiation))
16885 if (!COMPLETE_TYPE_P (instantiation))
16887 instantiate_class_template (instantiation);
16888 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16889 for (fn = TYPE_METHODS (instantiation);
16891 fn = TREE_CHAIN (fn))
16892 if (! DECL_ARTIFICIAL (fn))
16893 instantiate_decl (fn,
16895 /*expl_inst_class_mem_p=*/false);
16896 if (COMPLETE_TYPE_P (instantiation))
16900 complete = COMPLETE_TYPE_P (instantiation);
16904 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16905 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16908 = instantiate_decl (instantiation,
16910 /*expl_inst_class_mem_p=*/false);
16911 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16915 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16916 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16920 /* If INSTANTIATION has been instantiated, then we don't
16921 need to consider it again in the future. */
16929 current_tinst_level = NULL;
16931 last_pending_template = last;
16933 while (reconsider);
16935 input_location = saved_loc;
16938 /* Substitute ARGVEC into T, which is a list of initializers for
16939 either base class or a non-static data member. The TREE_PURPOSEs
16940 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16941 instantiate_decl. */
16944 tsubst_initializer_list (tree t, tree argvec)
16946 tree inits = NULL_TREE;
16948 for (; t; t = TREE_CHAIN (t))
16952 tree expanded_bases = NULL_TREE;
16953 tree expanded_arguments = NULL_TREE;
16956 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16961 /* Expand the base class expansion type into separate base
16963 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16964 tf_warning_or_error,
16966 if (expanded_bases == error_mark_node)
16969 /* We'll be building separate TREE_LISTs of arguments for
16971 len = TREE_VEC_LENGTH (expanded_bases);
16972 expanded_arguments = make_tree_vec (len);
16973 for (i = 0; i < len; i++)
16974 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16976 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16977 expand each argument in the TREE_VALUE of t. */
16978 expr = make_node (EXPR_PACK_EXPANSION);
16979 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16980 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16982 if (TREE_VALUE (t) == void_type_node)
16983 /* VOID_TYPE_NODE is used to indicate
16984 value-initialization. */
16986 for (i = 0; i < len; i++)
16987 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16991 /* Substitute parameter packs into each argument in the
16993 in_base_initializer = 1;
16994 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16996 tree expanded_exprs;
16998 /* Expand the argument. */
16999 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
17001 = tsubst_pack_expansion (expr, argvec,
17002 tf_warning_or_error,
17004 if (expanded_exprs == error_mark_node)
17007 /* Prepend each of the expanded expressions to the
17008 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
17009 for (i = 0; i < len; i++)
17011 TREE_VEC_ELT (expanded_arguments, i) =
17012 tree_cons (NULL_TREE,
17013 TREE_VEC_ELT (expanded_exprs, i),
17014 TREE_VEC_ELT (expanded_arguments, i));
17017 in_base_initializer = 0;
17019 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
17020 since we built them backwards. */
17021 for (i = 0; i < len; i++)
17023 TREE_VEC_ELT (expanded_arguments, i) =
17024 nreverse (TREE_VEC_ELT (expanded_arguments, i));
17029 for (i = 0; i < len; ++i)
17031 if (expanded_bases)
17033 decl = TREE_VEC_ELT (expanded_bases, i);
17034 decl = expand_member_init (decl);
17035 init = TREE_VEC_ELT (expanded_arguments, i);
17039 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
17040 tf_warning_or_error, NULL_TREE);
17042 decl = expand_member_init (decl);
17043 if (decl && !DECL_P (decl))
17044 in_base_initializer = 1;
17046 init = tsubst_expr (TREE_VALUE (t), argvec,
17047 tf_warning_or_error, NULL_TREE,
17048 /*integral_constant_expression_p=*/false);
17049 in_base_initializer = 0;
17054 init = build_tree_list (decl, init);
17055 TREE_CHAIN (init) = inits;
17063 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17066 set_current_access_from_decl (tree decl)
17068 if (TREE_PRIVATE (decl))
17069 current_access_specifier = access_private_node;
17070 else if (TREE_PROTECTED (decl))
17071 current_access_specifier = access_protected_node;
17073 current_access_specifier = access_public_node;
17076 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17077 is the instantiation (which should have been created with
17078 start_enum) and ARGS are the template arguments to use. */
17081 tsubst_enum (tree tag, tree newtag, tree args)
17085 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17090 decl = TREE_VALUE (e);
17091 /* Note that in a template enum, the TREE_VALUE is the
17092 CONST_DECL, not the corresponding INTEGER_CST. */
17093 value = tsubst_expr (DECL_INITIAL (decl),
17094 args, tf_warning_or_error, NULL_TREE,
17095 /*integral_constant_expression_p=*/true);
17097 /* Give this enumeration constant the correct access. */
17098 set_current_access_from_decl (decl);
17100 /* Actually build the enumerator itself. */
17101 build_enumerator (DECL_NAME (decl), value, newtag);
17104 finish_enum (newtag);
17105 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17106 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17109 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17110 its type -- but without substituting the innermost set of template
17111 arguments. So, innermost set of template parameters will appear in
17115 get_mostly_instantiated_function_type (tree decl)
17123 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17124 targs = DECL_TI_ARGS (decl);
17125 tparms = DECL_TEMPLATE_PARMS (tmpl);
17126 parm_depth = TMPL_PARMS_DEPTH (tparms);
17128 /* There should be as many levels of arguments as there are levels
17130 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
17132 fn_type = TREE_TYPE (tmpl);
17134 if (parm_depth == 1)
17135 /* No substitution is necessary. */
17139 int i, save_access_control;
17142 /* Replace the innermost level of the TARGS with NULL_TREEs to
17143 let tsubst know not to substitute for those parameters. */
17144 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
17145 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
17146 SET_TMPL_ARGS_LEVEL (partial_args, i,
17147 TMPL_ARGS_LEVEL (targs, i));
17148 SET_TMPL_ARGS_LEVEL (partial_args,
17149 TMPL_ARGS_DEPTH (targs),
17150 make_tree_vec (DECL_NTPARMS (tmpl)));
17152 /* Disable access control as this function is used only during
17154 save_access_control = flag_access_control;
17155 flag_access_control = 0;
17157 ++processing_template_decl;
17158 /* Now, do the (partial) substitution to figure out the
17159 appropriate function type. */
17160 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
17161 --processing_template_decl;
17163 /* Substitute into the template parameters to obtain the real
17164 innermost set of parameters. This step is important if the
17165 innermost set of template parameters contains value
17166 parameters whose types depend on outer template parameters. */
17167 TREE_VEC_LENGTH (partial_args)--;
17168 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
17170 flag_access_control = save_access_control;
17176 /* Return truthvalue if we're processing a template different from
17177 the last one involved in diagnostics. */
17179 problematic_instantiation_changed (void)
17181 return last_template_error_tick != tinst_level_tick;
17184 /* Remember current template involved in diagnostics. */
17186 record_last_problematic_instantiation (void)
17188 last_template_error_tick = tinst_level_tick;
17191 struct tinst_level *
17192 current_instantiation (void)
17194 return current_tinst_level;
17197 /* [temp.param] Check that template non-type parm TYPE is of an allowable
17198 type. Return zero for ok, nonzero for disallowed. Issue error and
17199 warning messages under control of COMPLAIN. */
17202 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
17204 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
17206 else if (POINTER_TYPE_P (type))
17208 else if (TYPE_PTR_TO_MEMBER_P (type))
17210 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
17212 else if (TREE_CODE (type) == TYPENAME_TYPE)
17215 if (complain & tf_error)
17216 error ("%q#T is not a valid type for a template constant parameter", type);
17220 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
17221 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
17224 dependent_type_p_r (tree type)
17230 A type is dependent if it is:
17232 -- a template parameter. Template template parameters are types
17233 for us (since TYPE_P holds true for them) so we handle
17235 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17236 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
17238 /* -- a qualified-id with a nested-name-specifier which contains a
17239 class-name that names a dependent type or whose unqualified-id
17240 names a dependent type. */
17241 if (TREE_CODE (type) == TYPENAME_TYPE)
17243 /* -- a cv-qualified type where the cv-unqualified type is
17245 type = TYPE_MAIN_VARIANT (type);
17246 /* -- a compound type constructed from any dependent type. */
17247 if (TYPE_PTR_TO_MEMBER_P (type))
17248 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
17249 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
17251 else if (TREE_CODE (type) == POINTER_TYPE
17252 || TREE_CODE (type) == REFERENCE_TYPE)
17253 return dependent_type_p (TREE_TYPE (type));
17254 else if (TREE_CODE (type) == FUNCTION_TYPE
17255 || TREE_CODE (type) == METHOD_TYPE)
17259 if (dependent_type_p (TREE_TYPE (type)))
17261 for (arg_type = TYPE_ARG_TYPES (type);
17263 arg_type = TREE_CHAIN (arg_type))
17264 if (dependent_type_p (TREE_VALUE (arg_type)))
17268 /* -- an array type constructed from any dependent type or whose
17269 size is specified by a constant expression that is
17270 value-dependent. */
17271 if (TREE_CODE (type) == ARRAY_TYPE)
17273 if (TYPE_DOMAIN (type)
17274 && dependent_type_p (TYPE_DOMAIN (type)))
17276 return dependent_type_p (TREE_TYPE (type));
17278 else if (TREE_CODE (type) == INTEGER_TYPE
17279 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
17281 /* If this is the TYPE_DOMAIN of an array type, consider it
17282 dependent. We already checked for value-dependence in
17283 compute_array_index_type. */
17284 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
17287 /* -- a template-id in which either the template name is a template
17289 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
17291 /* ... or any of the template arguments is a dependent type or
17292 an expression that is type-dependent or value-dependent. */
17293 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
17294 && (any_dependent_template_arguments_p
17295 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
17298 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
17299 argument of the `typeof' expression is not type-dependent, then
17300 it should already been have resolved. */
17301 if (TREE_CODE (type) == TYPEOF_TYPE
17302 || TREE_CODE (type) == DECLTYPE_TYPE)
17305 /* A template argument pack is dependent if any of its packed
17307 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
17309 tree args = ARGUMENT_PACK_ARGS (type);
17310 int i, len = TREE_VEC_LENGTH (args);
17311 for (i = 0; i < len; ++i)
17312 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17316 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17317 be template parameters. */
17318 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17321 /* The standard does not specifically mention types that are local
17322 to template functions or local classes, but they should be
17323 considered dependent too. For example:
17325 template <int I> void f() {
17330 The size of `E' cannot be known until the value of `I' has been
17331 determined. Therefore, `E' must be considered dependent. */
17332 scope = TYPE_CONTEXT (type);
17333 if (scope && TYPE_P (scope))
17334 return dependent_type_p (scope);
17335 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17336 return type_dependent_expression_p (scope);
17338 /* Other types are non-dependent. */
17342 /* Returns TRUE if TYPE is dependent, in the sense of
17343 [temp.dep.type]. */
17346 dependent_type_p (tree type)
17348 /* If there are no template parameters in scope, then there can't be
17349 any dependent types. */
17350 if (!processing_template_decl)
17352 /* If we are not processing a template, then nobody should be
17353 providing us with a dependent type. */
17355 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17359 /* If the type is NULL, we have not computed a type for the entity
17360 in question; in that case, the type is dependent. */
17364 /* Erroneous types can be considered non-dependent. */
17365 if (type == error_mark_node)
17368 /* If we have not already computed the appropriate value for TYPE,
17370 if (!TYPE_DEPENDENT_P_VALID (type))
17372 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17373 TYPE_DEPENDENT_P_VALID (type) = 1;
17376 return TYPE_DEPENDENT_P (type);
17379 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17380 lookup. In other words, a dependent type that is not the current
17384 dependent_scope_p (tree scope)
17386 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17387 && !currently_open_class (scope));
17390 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
17393 dependent_scope_ref_p (tree expression, bool criterion (tree))
17398 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
17400 if (!TYPE_P (TREE_OPERAND (expression, 0)))
17403 scope = TREE_OPERAND (expression, 0);
17404 name = TREE_OPERAND (expression, 1);
17408 An id-expression is type-dependent if it contains a
17409 nested-name-specifier that contains a class-name that names a
17411 /* The suggested resolution to Core Issue 224 implies that if the
17412 qualifying type is the current class, then we must peek
17415 && currently_open_class (scope)
17416 && !criterion (name))
17418 if (dependent_type_p (scope))
17424 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17425 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17429 value_dependent_expression_p (tree expression)
17431 if (!processing_template_decl)
17434 /* A name declared with a dependent type. */
17435 if (DECL_P (expression) && type_dependent_expression_p (expression))
17438 switch (TREE_CODE (expression))
17440 case IDENTIFIER_NODE:
17441 /* A name that has not been looked up -- must be dependent. */
17444 case TEMPLATE_PARM_INDEX:
17445 /* A non-type template parm. */
17449 /* A non-type template parm. */
17450 if (DECL_TEMPLATE_PARM_P (expression))
17452 return value_dependent_expression_p (DECL_INITIAL (expression));
17455 /* A constant with integral or enumeration type and is initialized
17456 with an expression that is value-dependent. */
17457 if (DECL_INITIAL (expression)
17458 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17459 && value_dependent_expression_p (DECL_INITIAL (expression)))
17463 case DYNAMIC_CAST_EXPR:
17464 case STATIC_CAST_EXPR:
17465 case CONST_CAST_EXPR:
17466 case REINTERPRET_CAST_EXPR:
17468 /* These expressions are value-dependent if the type to which
17469 the cast occurs is dependent or the expression being casted
17470 is value-dependent. */
17472 tree type = TREE_TYPE (expression);
17474 if (dependent_type_p (type))
17477 /* A functional cast has a list of operands. */
17478 expression = TREE_OPERAND (expression, 0);
17481 /* If there are no operands, it must be an expression such
17482 as "int()". This should not happen for aggregate types
17483 because it would form non-constant expressions. */
17484 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17489 if (TREE_CODE (expression) == TREE_LIST)
17490 return any_value_dependent_elements_p (expression);
17492 return value_dependent_expression_p (expression);
17497 /* A `sizeof' expression is value-dependent if the operand is
17498 type-dependent or is a pack expansion. */
17499 expression = TREE_OPERAND (expression, 0);
17500 if (PACK_EXPANSION_P (expression))
17502 else if (TYPE_P (expression))
17503 return dependent_type_p (expression);
17504 return type_dependent_expression_p (expression);
17507 return dependent_scope_ref_p (expression, value_dependent_expression_p);
17509 case COMPONENT_REF:
17510 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17511 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17514 /* A CALL_EXPR may appear in a constant expression if it is a
17515 call to a builtin function, e.g., __builtin_constant_p. All
17516 such calls are value-dependent. */
17519 case NONTYPE_ARGUMENT_PACK:
17520 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17521 is value-dependent. */
17523 tree values = ARGUMENT_PACK_ARGS (expression);
17524 int i, len = TREE_VEC_LENGTH (values);
17526 for (i = 0; i < len; ++i)
17527 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17535 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17536 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17537 || (type2 ? dependent_type_p (type2) : false));
17541 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17542 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17545 /* A constant expression is value-dependent if any subexpression is
17546 value-dependent. */
17547 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17549 case tcc_reference:
17551 return (value_dependent_expression_p
17552 (TREE_OPERAND (expression, 0)));
17554 case tcc_comparison:
17556 return ((value_dependent_expression_p
17557 (TREE_OPERAND (expression, 0)))
17558 || (value_dependent_expression_p
17559 (TREE_OPERAND (expression, 1))));
17561 case tcc_expression:
17565 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17566 /* In some cases, some of the operands may be missing.
17567 (For example, in the case of PREDECREMENT_EXPR, the
17568 amount to increment by may be missing.) That doesn't
17569 make the expression dependent. */
17570 if (TREE_OPERAND (expression, i)
17571 && (value_dependent_expression_p
17572 (TREE_OPERAND (expression, i))))
17582 /* The expression is not value-dependent. */
17586 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17587 [temp.dep.expr]. */
17590 type_dependent_expression_p (tree expression)
17592 if (!processing_template_decl)
17595 if (expression == error_mark_node)
17598 /* An unresolved name is always dependent. */
17599 if (TREE_CODE (expression) == IDENTIFIER_NODE
17600 || TREE_CODE (expression) == USING_DECL)
17603 /* Some expression forms are never type-dependent. */
17604 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17605 || TREE_CODE (expression) == SIZEOF_EXPR
17606 || TREE_CODE (expression) == ALIGNOF_EXPR
17607 || TREE_CODE (expression) == TRAIT_EXPR
17608 || TREE_CODE (expression) == TYPEID_EXPR
17609 || TREE_CODE (expression) == DELETE_EXPR
17610 || TREE_CODE (expression) == VEC_DELETE_EXPR
17611 || TREE_CODE (expression) == THROW_EXPR)
17614 /* The types of these expressions depends only on the type to which
17615 the cast occurs. */
17616 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17617 || TREE_CODE (expression) == STATIC_CAST_EXPR
17618 || TREE_CODE (expression) == CONST_CAST_EXPR
17619 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17620 || TREE_CODE (expression) == CAST_EXPR)
17621 return dependent_type_p (TREE_TYPE (expression));
17623 /* The types of these expressions depends only on the type created
17624 by the expression. */
17625 if (TREE_CODE (expression) == NEW_EXPR
17626 || TREE_CODE (expression) == VEC_NEW_EXPR)
17628 /* For NEW_EXPR tree nodes created inside a template, either
17629 the object type itself or a TREE_LIST may appear as the
17631 tree type = TREE_OPERAND (expression, 1);
17632 if (TREE_CODE (type) == TREE_LIST)
17633 /* This is an array type. We need to check array dimensions
17635 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17636 || value_dependent_expression_p
17637 (TREE_OPERAND (TREE_VALUE (type), 1));
17639 return dependent_type_p (type);
17642 if (TREE_CODE (expression) == SCOPE_REF
17643 && dependent_scope_ref_p (expression,
17644 type_dependent_expression_p))
17647 if (TREE_CODE (expression) == FUNCTION_DECL
17648 && DECL_LANG_SPECIFIC (expression)
17649 && DECL_TEMPLATE_INFO (expression)
17650 && (any_dependent_template_arguments_p
17651 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17654 if (TREE_CODE (expression) == TEMPLATE_DECL
17655 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17658 if (TREE_CODE (expression) == STMT_EXPR)
17659 expression = stmt_expr_value_expr (expression);
17661 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17666 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17668 if (type_dependent_expression_p (elt))
17674 if (TREE_TYPE (expression) == unknown_type_node)
17676 if (TREE_CODE (expression) == ADDR_EXPR)
17677 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17678 if (TREE_CODE (expression) == COMPONENT_REF
17679 || TREE_CODE (expression) == OFFSET_REF)
17681 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17683 expression = TREE_OPERAND (expression, 1);
17684 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17687 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17688 if (TREE_CODE (expression) == SCOPE_REF)
17691 if (TREE_CODE (expression) == BASELINK)
17692 expression = BASELINK_FUNCTIONS (expression);
17694 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17696 if (any_dependent_template_arguments_p
17697 (TREE_OPERAND (expression, 1)))
17699 expression = TREE_OPERAND (expression, 0);
17701 gcc_assert (TREE_CODE (expression) == OVERLOAD
17702 || TREE_CODE (expression) == FUNCTION_DECL);
17706 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17708 expression = OVL_NEXT (expression);
17713 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17715 return (dependent_type_p (TREE_TYPE (expression)));
17718 /* Like type_dependent_expression_p, but it also works while not processing
17719 a template definition, i.e. during substitution or mangling. */
17722 type_dependent_expression_p_push (tree expr)
17725 ++processing_template_decl;
17726 b = type_dependent_expression_p (expr);
17727 --processing_template_decl;
17731 /* Returns TRUE if ARGS contains a type-dependent expression. */
17734 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17739 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
17741 if (type_dependent_expression_p (arg))
17747 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17748 expressions) contains any value-dependent expressions. */
17751 any_value_dependent_elements_p (const_tree list)
17753 for (; list; list = TREE_CHAIN (list))
17754 if (value_dependent_expression_p (TREE_VALUE (list)))
17760 /* Returns TRUE if the ARG (a template argument) is dependent. */
17763 dependent_template_arg_p (tree arg)
17765 if (!processing_template_decl)
17768 if (TREE_CODE (arg) == TEMPLATE_DECL
17769 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17770 return dependent_template_p (arg);
17771 else if (ARGUMENT_PACK_P (arg))
17773 tree args = ARGUMENT_PACK_ARGS (arg);
17774 int i, len = TREE_VEC_LENGTH (args);
17775 for (i = 0; i < len; ++i)
17777 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17783 else if (TYPE_P (arg))
17784 return dependent_type_p (arg);
17786 return (type_dependent_expression_p (arg)
17787 || value_dependent_expression_p (arg));
17790 /* Returns true if ARGS (a collection of template arguments) contains
17791 any types that require structural equality testing. */
17794 any_template_arguments_need_structural_equality_p (tree args)
17801 if (args == error_mark_node)
17804 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17806 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17807 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17809 tree arg = TREE_VEC_ELT (level, j);
17810 tree packed_args = NULL_TREE;
17813 if (ARGUMENT_PACK_P (arg))
17815 /* Look inside the argument pack. */
17816 packed_args = ARGUMENT_PACK_ARGS (arg);
17817 len = TREE_VEC_LENGTH (packed_args);
17820 for (k = 0; k < len; ++k)
17823 arg = TREE_VEC_ELT (packed_args, k);
17825 if (error_operand_p (arg))
17827 else if (TREE_CODE (arg) == TEMPLATE_DECL
17828 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17830 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17832 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17833 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17842 /* Returns true if ARGS (a collection of template arguments) contains
17843 any dependent arguments. */
17846 any_dependent_template_arguments_p (const_tree args)
17853 if (args == error_mark_node)
17856 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17858 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17859 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17860 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17867 /* Returns TRUE if the template TMPL is dependent. */
17870 dependent_template_p (tree tmpl)
17872 if (TREE_CODE (tmpl) == OVERLOAD)
17876 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17878 tmpl = OVL_CHAIN (tmpl);
17883 /* Template template parameters are dependent. */
17884 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17885 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17887 /* So are names that have not been looked up. */
17888 if (TREE_CODE (tmpl) == SCOPE_REF
17889 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17891 /* So are member templates of dependent classes. */
17892 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17893 return dependent_type_p (DECL_CONTEXT (tmpl));
17897 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17900 dependent_template_id_p (tree tmpl, tree args)
17902 return (dependent_template_p (tmpl)
17903 || any_dependent_template_arguments_p (args));
17906 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17910 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17914 if (!processing_template_decl)
17917 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17919 tree decl = TREE_VEC_ELT (declv, i);
17920 tree init = TREE_VEC_ELT (initv, i);
17921 tree cond = TREE_VEC_ELT (condv, i);
17922 tree incr = TREE_VEC_ELT (incrv, i);
17924 if (type_dependent_expression_p (decl))
17927 if (init && type_dependent_expression_p (init))
17930 if (type_dependent_expression_p (cond))
17933 if (COMPARISON_CLASS_P (cond)
17934 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17935 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17938 if (TREE_CODE (incr) == MODOP_EXPR)
17940 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17941 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17944 else if (type_dependent_expression_p (incr))
17946 else if (TREE_CODE (incr) == MODIFY_EXPR)
17948 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17950 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17952 tree t = TREE_OPERAND (incr, 1);
17953 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17954 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17963 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17964 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17965 no such TYPE can be found. Note that this function peers inside
17966 uninstantiated templates and therefore should be used only in
17967 extremely limited situations. ONLY_CURRENT_P restricts this
17968 peering to the currently open classes hierarchy (which is required
17969 when comparing types). */
17972 resolve_typename_type (tree type, bool only_current_p)
17981 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17983 scope = TYPE_CONTEXT (type);
17984 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17985 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17986 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17987 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17988 identifier of the TYPENAME_TYPE anymore.
17989 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17990 TYPENAME_TYPE instead, we avoid messing up with a possible
17991 typedef variant case. */
17992 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17994 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17995 it first before we can figure out what NAME refers to. */
17996 if (TREE_CODE (scope) == TYPENAME_TYPE)
17997 scope = resolve_typename_type (scope, only_current_p);
17998 /* If we don't know what SCOPE refers to, then we cannot resolve the
18000 if (TREE_CODE (scope) == TYPENAME_TYPE)
18002 /* If the SCOPE is a template type parameter, we have no way of
18003 resolving the name. */
18004 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
18006 /* If the SCOPE is not the current instantiation, there's no reason
18007 to look inside it. */
18008 if (only_current_p && !currently_open_class (scope))
18010 /* If this is a typedef, we don't want to look inside (c++/11987). */
18011 if (typedef_variant_p (type))
18013 /* If SCOPE isn't the template itself, it will not have a valid
18014 TYPE_FIELDS list. */
18015 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
18016 /* scope is either the template itself or a compatible instantiation
18017 like X<T>, so look up the name in the original template. */
18018 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
18020 /* scope is a partial instantiation, so we can't do the lookup or we
18021 will lose the template arguments. */
18023 /* Enter the SCOPE so that name lookup will be resolved as if we
18024 were in the class definition. In particular, SCOPE will no
18025 longer be considered a dependent type. */
18026 pushed_scope = push_scope (scope);
18027 /* Look up the declaration. */
18028 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
18030 result = NULL_TREE;
18032 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
18033 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
18036 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
18037 && TREE_CODE (decl) == TYPE_DECL)
18039 result = TREE_TYPE (decl);
18040 if (result == error_mark_node)
18041 result = NULL_TREE;
18043 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
18044 && DECL_CLASS_TEMPLATE_P (decl))
18048 /* Obtain the template and the arguments. */
18049 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
18050 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
18051 /* Instantiate the template. */
18052 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
18053 /*entering_scope=*/0,
18054 tf_error | tf_user);
18055 if (result == error_mark_node)
18056 result = NULL_TREE;
18059 /* Leave the SCOPE. */
18061 pop_scope (pushed_scope);
18063 /* If we failed to resolve it, return the original typename. */
18067 /* If lookup found a typename type, resolve that too. */
18068 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
18070 /* Ill-formed programs can cause infinite recursion here, so we
18071 must catch that. */
18072 TYPENAME_IS_RESOLVING_P (type) = 1;
18073 result = resolve_typename_type (result, only_current_p);
18074 TYPENAME_IS_RESOLVING_P (type) = 0;
18077 /* Qualify the resulting type. */
18078 quals = cp_type_quals (type);
18080 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
18085 /* EXPR is an expression which is not type-dependent. Return a proxy
18086 for EXPR that can be used to compute the types of larger
18087 expressions containing EXPR. */
18090 build_non_dependent_expr (tree expr)
18094 /* Preserve null pointer constants so that the type of things like
18095 "p == 0" where "p" is a pointer can be determined. */
18096 if (null_ptr_cst_p (expr))
18098 /* Preserve OVERLOADs; the functions must be available to resolve
18101 if (TREE_CODE (inner_expr) == STMT_EXPR)
18102 inner_expr = stmt_expr_value_expr (inner_expr);
18103 if (TREE_CODE (inner_expr) == ADDR_EXPR)
18104 inner_expr = TREE_OPERAND (inner_expr, 0);
18105 if (TREE_CODE (inner_expr) == COMPONENT_REF)
18106 inner_expr = TREE_OPERAND (inner_expr, 1);
18107 if (is_overloaded_fn (inner_expr)
18108 || TREE_CODE (inner_expr) == OFFSET_REF)
18110 /* There is no need to return a proxy for a variable. */
18111 if (TREE_CODE (expr) == VAR_DECL)
18113 /* Preserve string constants; conversions from string constants to
18114 "char *" are allowed, even though normally a "const char *"
18115 cannot be used to initialize a "char *". */
18116 if (TREE_CODE (expr) == STRING_CST)
18118 /* Preserve arithmetic constants, as an optimization -- there is no
18119 reason to create a new node. */
18120 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
18122 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
18123 There is at least one place where we want to know that a
18124 particular expression is a throw-expression: when checking a ?:
18125 expression, there are special rules if the second or third
18126 argument is a throw-expression. */
18127 if (TREE_CODE (expr) == THROW_EXPR)
18130 if (TREE_CODE (expr) == COND_EXPR)
18131 return build3 (COND_EXPR,
18133 TREE_OPERAND (expr, 0),
18134 (TREE_OPERAND (expr, 1)
18135 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
18136 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
18137 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
18138 if (TREE_CODE (expr) == COMPOUND_EXPR
18139 && !COMPOUND_EXPR_OVERLOADED (expr))
18140 return build2 (COMPOUND_EXPR,
18142 TREE_OPERAND (expr, 0),
18143 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
18145 /* If the type is unknown, it can't really be non-dependent */
18146 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
18148 /* Otherwise, build a NON_DEPENDENT_EXPR.
18150 REFERENCE_TYPEs are not stripped for expressions in templates
18151 because doing so would play havoc with mangling. Consider, for
18154 template <typename T> void f<T& g>() { g(); }
18156 In the body of "f", the expression for "g" will have
18157 REFERENCE_TYPE, even though the standard says that it should
18158 not. The reason is that we must preserve the syntactic form of
18159 the expression so that mangling (say) "f<g>" inside the body of
18160 "f" works out correctly. Therefore, the REFERENCE_TYPE is
18162 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
18165 /* ARGS is a vector of expressions as arguments to a function call.
18166 Replace the arguments with equivalent non-dependent expressions.
18167 This modifies ARGS in place. */
18170 make_args_non_dependent (VEC(tree,gc) *args)
18175 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
18177 tree newarg = build_non_dependent_expr (arg);
18179 VEC_replace (tree, args, ix, newarg);
18183 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
18184 with a level one deeper than the actual template parms. */
18189 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
18190 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
18191 TYPE_DECL, get_identifier ("auto"), au);
18192 TYPE_STUB_DECL (au) = TYPE_NAME (au);
18193 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
18194 (0, processing_template_decl + 1, processing_template_decl + 1,
18195 TYPE_NAME (au), NULL_TREE);
18196 TYPE_CANONICAL (au) = canonical_type_parameter (au);
18197 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
18198 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
18203 /* Given type ARG, return std::initializer_list<ARG>. */
18208 tree std_init_list = namespace_binding
18209 (get_identifier ("initializer_list"), std_node);
18211 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
18213 error ("deducing from brace-enclosed initializer list requires "
18214 "#include <initializer_list>");
18215 return error_mark_node;
18217 argvec = make_tree_vec (1);
18218 TREE_VEC_ELT (argvec, 0) = arg;
18219 return lookup_template_class (std_init_list, argvec, NULL_TREE,
18220 NULL_TREE, 0, tf_warning_or_error);
18223 /* Replace auto in TYPE with std::initializer_list<auto>. */
18226 listify_autos (tree type, tree auto_node)
18228 tree init_auto = listify (auto_node);
18229 tree argvec = make_tree_vec (1);
18230 TREE_VEC_ELT (argvec, 0) = init_auto;
18231 if (processing_template_decl)
18232 argvec = add_to_template_args (current_template_args (), argvec);
18233 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18236 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
18237 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
18240 do_auto_deduction (tree type, tree init, tree auto_node)
18242 tree parms, tparms, targs;
18246 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
18247 with either a new invented type template parameter U or, if the
18248 initializer is a braced-init-list (8.5.4), with
18249 std::initializer_list<U>. */
18250 if (BRACE_ENCLOSED_INITIALIZER_P (init))
18251 type = listify_autos (type, auto_node);
18253 parms = build_tree_list (NULL_TREE, type);
18255 tparms = make_tree_vec (1);
18256 targs = make_tree_vec (1);
18257 TREE_VEC_ELT (tparms, 0)
18258 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
18259 val = type_unification_real (tparms, targs, parms, args, 1, 0,
18260 DEDUCE_CALL, LOOKUP_NORMAL);
18263 error ("unable to deduce %qT from %qE", type, init);
18264 return error_mark_node;
18267 /* If the list of declarators contains more than one declarator, the type
18268 of each declared variable is determined as described above. If the
18269 type deduced for the template parameter U is not the same in each
18270 deduction, the program is ill-formed. */
18271 if (TREE_TYPE (auto_node)
18272 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
18274 error ("inconsistent deduction for %qT: %qT and then %qT",
18275 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
18276 return error_mark_node;
18278 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
18280 if (processing_template_decl)
18281 targs = add_to_template_args (current_template_args (), targs);
18282 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
18285 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
18289 splice_late_return_type (tree type, tree late_return_type)
18293 if (late_return_type == NULL_TREE)
18295 argvec = make_tree_vec (1);
18296 TREE_VEC_ELT (argvec, 0) = late_return_type;
18297 if (processing_template_decl)
18298 argvec = add_to_template_args (current_template_args (), argvec);
18299 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18302 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
18305 is_auto (const_tree type)
18307 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18308 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
18314 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
18315 appear as a type-specifier for the declaration in question, we don't
18316 have to look through the whole type. */
18319 type_uses_auto (tree type)
18321 enum tree_code code;
18322 if (is_auto (type))
18325 code = TREE_CODE (type);
18327 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18328 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18329 || code == METHOD_TYPE || code == ARRAY_TYPE)
18330 return type_uses_auto (TREE_TYPE (type));
18332 if (TYPE_PTRMEMFUNC_P (type))
18333 return type_uses_auto (TREE_TYPE (TREE_TYPE
18334 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18339 /* For a given template T, return the vector of typedefs referenced
18340 in T for which access check is needed at T instantiation time.
18341 T is either a FUNCTION_DECL or a RECORD_TYPE.
18342 Those typedefs were added to T by the function
18343 append_type_to_template_for_access_check. */
18345 VEC(qualified_typedef_usage_t,gc)*
18346 get_types_needing_access_check (tree t)
18349 VEC(qualified_typedef_usage_t,gc) *result = NULL;
18351 if (!t || t == error_mark_node)
18354 if (!(ti = get_template_info (t)))
18357 if (CLASS_TYPE_P (t)
18358 || TREE_CODE (t) == FUNCTION_DECL)
18360 if (!TI_TEMPLATE (ti))
18363 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
18369 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
18370 tied to T. That list of typedefs will be access checked at
18371 T instantiation time.
18372 T is either a FUNCTION_DECL or a RECORD_TYPE.
18373 TYPE_DECL is a TYPE_DECL node representing a typedef.
18374 SCOPE is the scope through which TYPE_DECL is accessed.
18375 LOCATION is the location of the usage point of TYPE_DECL.
18377 This function is a subroutine of
18378 append_type_to_template_for_access_check. */
18381 append_type_to_template_for_access_check_1 (tree t,
18384 location_t location)
18386 qualified_typedef_usage_t typedef_usage;
18389 if (!t || t == error_mark_node)
18392 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
18393 || CLASS_TYPE_P (t))
18395 && TREE_CODE (type_decl) == TYPE_DECL
18398 if (!(ti = get_template_info (t)))
18401 gcc_assert (TI_TEMPLATE (ti));
18403 typedef_usage.typedef_decl = type_decl;
18404 typedef_usage.context = scope;
18405 typedef_usage.locus = location;
18407 VEC_safe_push (qualified_typedef_usage_t, gc,
18408 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
18412 /* Append TYPE_DECL to the template TEMPL.
18413 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
18414 At TEMPL instanciation time, TYPE_DECL will be checked to see
18415 if it can be accessed through SCOPE.
18416 LOCATION is the location of the usage point of TYPE_DECL.
18418 e.g. consider the following code snippet:
18425 template<class U> struct S
18427 C::myint mi; // <-- usage point of the typedef C::myint
18432 At S<char> instantiation time, we need to check the access of C::myint
18433 In other words, we need to check the access of the myint typedef through
18434 the C scope. For that purpose, this function will add the myint typedef
18435 and the scope C through which its being accessed to a list of typedefs
18436 tied to the template S. That list will be walked at template instantiation
18437 time and access check performed on each typedefs it contains.
18438 Note that this particular code snippet should yield an error because
18439 myint is private to C. */
18442 append_type_to_template_for_access_check (tree templ,
18445 location_t location)
18447 qualified_typedef_usage_t *iter;
18450 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
18452 /* Make sure we don't append the type to the template twice. */
18454 VEC_iterate (qualified_typedef_usage_t,
18455 get_types_needing_access_check (templ),
18458 if (iter->typedef_decl == type_decl && scope == iter->context)
18461 append_type_to_template_for_access_check_1 (templ, type_decl,
18465 /* Set up the hash tables for template instantiations. */
18468 init_template_processing (void)
18470 decl_specializations = htab_create_ggc (37,
18471 hash_specialization,
18472 eq_specializations,
18474 type_specializations = htab_create_ggc (37,
18475 hash_specialization,
18476 eq_specializations,
18480 #include "gt-cp-pt.h"