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 int push_tinst_level (tree);
123 static void pop_tinst_level (void);
124 static tree reopen_tinst_level (struct tinst_level *);
125 static tree tsubst_initializer_list (tree, tree);
126 static tree get_class_bindings (tree, tree, tree);
127 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
129 static void tsubst_enum (tree, tree, tree);
130 static tree add_to_template_args (tree, tree);
131 static tree add_outermost_template_args (tree, tree);
132 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
133 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
135 static int type_unification_real (tree, tree, tree, const tree *,
136 unsigned int, int, unification_kind_t, int);
137 static void note_template_header (int);
138 static tree convert_nontype_argument_function (tree, tree);
139 static tree convert_nontype_argument (tree, tree);
140 static tree convert_template_argument (tree, tree, tree,
141 tsubst_flags_t, int, tree);
142 static int for_each_template_parm (tree, tree_fn_t, void*,
143 struct pointer_set_t*, bool);
144 static tree expand_template_argument_pack (tree);
145 static tree build_template_parm_index (int, int, int, tree, tree);
146 static bool inline_needs_template_parms (tree);
147 static void push_inline_template_parms_recursive (tree, int);
148 static tree retrieve_local_specialization (tree);
149 static void register_local_specialization (tree, tree);
150 static hashval_t hash_specialization (const void *p);
151 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
152 static int mark_template_parm (tree, void *);
153 static int template_parm_this_level_p (tree, void *);
154 static tree tsubst_friend_function (tree, tree);
155 static tree tsubst_friend_class (tree, tree);
156 static int can_complete_type_without_circularity (tree);
157 static tree get_bindings (tree, tree, tree, bool);
158 static int template_decl_level (tree);
159 static int check_cv_quals_for_unify (int, tree, tree);
160 static void template_parm_level_and_index (tree, int*, int*);
161 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
162 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
165 static void regenerate_decl_from_template (tree, tree);
166 static tree most_specialized_class (tree, tree);
167 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
168 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
170 static bool check_specialization_scope (void);
171 static tree process_partial_specialization (tree);
172 static void set_current_access_from_decl (tree);
173 static tree get_template_base (tree, tree, tree, tree);
174 static tree try_class_unification (tree, tree, tree, tree);
175 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
177 static bool template_template_parm_bindings_ok_p (tree, tree);
178 static int template_args_equal (tree, tree);
179 static void tsubst_default_arguments (tree);
180 static tree for_each_template_parm_r (tree *, int *, void *);
181 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
182 static void copy_default_args_to_explicit_spec (tree);
183 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
184 static int eq_local_specializations (const void *, const void *);
185 static bool dependent_template_arg_p (tree);
186 static bool any_template_arguments_need_structural_equality_p (tree);
187 static bool dependent_type_p_r (tree);
188 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
189 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
190 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
191 static tree tsubst_decl (tree, tree, tsubst_flags_t);
192 static void perform_typedefs_access_check (tree tmpl, tree targs);
193 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
195 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
196 static tree listify (tree);
197 static tree listify_autos (tree, tree);
199 /* Make the current scope suitable for access checking when we are
200 processing T. T can be FUNCTION_DECL for instantiated function
201 template, or VAR_DECL for static member variable (need by
202 instantiate_decl). */
205 push_access_scope (tree t)
207 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
208 || TREE_CODE (t) == VAR_DECL);
210 if (DECL_FRIEND_CONTEXT (t))
211 push_nested_class (DECL_FRIEND_CONTEXT (t));
212 else if (DECL_CLASS_SCOPE_P (t))
213 push_nested_class (DECL_CONTEXT (t));
215 push_to_top_level ();
217 if (TREE_CODE (t) == FUNCTION_DECL)
219 saved_access_scope = tree_cons
220 (NULL_TREE, current_function_decl, saved_access_scope);
221 current_function_decl = t;
225 /* Restore the scope set up by push_access_scope. T is the node we
229 pop_access_scope (tree t)
231 if (TREE_CODE (t) == FUNCTION_DECL)
233 current_function_decl = TREE_VALUE (saved_access_scope);
234 saved_access_scope = TREE_CHAIN (saved_access_scope);
237 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
240 pop_from_top_level ();
243 /* Do any processing required when DECL (a member template
244 declaration) is finished. Returns the TEMPLATE_DECL corresponding
245 to DECL, unless it is a specialization, in which case the DECL
246 itself is returned. */
249 finish_member_template_decl (tree decl)
251 if (decl == error_mark_node)
252 return error_mark_node;
254 gcc_assert (DECL_P (decl));
256 if (TREE_CODE (decl) == TYPE_DECL)
260 type = TREE_TYPE (decl);
261 if (type == error_mark_node)
262 return error_mark_node;
263 if (MAYBE_CLASS_TYPE_P (type)
264 && CLASSTYPE_TEMPLATE_INFO (type)
265 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
267 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
268 check_member_template (tmpl);
273 else if (TREE_CODE (decl) == FIELD_DECL)
274 error ("data member %qD cannot be a member template", decl);
275 else if (DECL_TEMPLATE_INFO (decl))
277 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
279 check_member_template (DECL_TI_TEMPLATE (decl));
280 return DECL_TI_TEMPLATE (decl);
286 error ("invalid member template declaration %qD", decl);
288 return error_mark_node;
291 /* Create a template info node. */
294 build_template_info (tree template_decl, tree template_args)
296 tree result = make_node (TEMPLATE_INFO);
297 TI_TEMPLATE (result) = template_decl;
298 TI_ARGS (result) = template_args;
302 /* Return the template info node corresponding to T, whatever T is. */
305 get_template_info (const_tree t)
307 tree tinfo = NULL_TREE;
309 if (!t || t == error_mark_node)
312 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
313 tinfo = DECL_TEMPLATE_INFO (t);
315 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
318 if (TAGGED_TYPE_P (t))
319 tinfo = TYPE_TEMPLATE_INFO (t);
320 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
321 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
326 /* Returns the template nesting level of the indicated class TYPE.
336 A<T>::B<U> has depth two, while A<T> has depth one.
337 Both A<T>::B<int> and A<int>::B<U> have depth one, if
338 they are instantiations, not specializations.
340 This function is guaranteed to return 0 if passed NULL_TREE so
341 that, for example, `template_class_depth (current_class_type)' is
345 template_class_depth (tree type)
350 type && TREE_CODE (type) != NAMESPACE_DECL;
351 type = (TREE_CODE (type) == FUNCTION_DECL)
352 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
354 tree tinfo = get_template_info (type);
356 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
357 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
364 /* Subroutine of maybe_begin_member_template_processing.
365 Returns true if processing DECL needs us to push template parms. */
368 inline_needs_template_parms (tree decl)
370 if (! DECL_TEMPLATE_INFO (decl))
373 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
374 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
377 /* Subroutine of maybe_begin_member_template_processing.
378 Push the template parms in PARMS, starting from LEVELS steps into the
379 chain, and ending at the beginning, since template parms are listed
383 push_inline_template_parms_recursive (tree parmlist, int levels)
385 tree parms = TREE_VALUE (parmlist);
389 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
391 ++processing_template_decl;
392 current_template_parms
393 = tree_cons (size_int (processing_template_decl),
394 parms, current_template_parms);
395 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
397 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
399 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
401 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
403 if (parm == error_mark_node)
406 gcc_assert (DECL_P (parm));
408 switch (TREE_CODE (parm))
417 /* Make a CONST_DECL as is done in process_template_parm.
418 It is ugly that we recreate this here; the original
419 version built in process_template_parm is no longer
421 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
422 CONST_DECL, DECL_NAME (parm),
424 DECL_ARTIFICIAL (decl) = 1;
425 TREE_CONSTANT (decl) = 1;
426 TREE_READONLY (decl) = 1;
427 DECL_INITIAL (decl) = DECL_INITIAL (parm);
428 SET_DECL_TEMPLATE_PARM_P (decl);
439 /* Restore the template parameter context for a member template or
440 a friend template defined in a class definition. */
443 maybe_begin_member_template_processing (tree decl)
448 if (inline_needs_template_parms (decl))
450 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
451 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
453 if (DECL_TEMPLATE_SPECIALIZATION (decl))
456 parms = TREE_CHAIN (parms);
459 push_inline_template_parms_recursive (parms, levels);
462 /* Remember how many levels of template parameters we pushed so that
463 we can pop them later. */
464 VEC_safe_push (int, heap, inline_parm_levels, levels);
467 /* Undo the effects of maybe_begin_member_template_processing. */
470 maybe_end_member_template_processing (void)
475 if (VEC_length (int, inline_parm_levels) == 0)
478 last = VEC_pop (int, inline_parm_levels);
479 for (i = 0; i < last; ++i)
481 --processing_template_decl;
482 current_template_parms = TREE_CHAIN (current_template_parms);
487 /* Return a new template argument vector which contains all of ARGS,
488 but has as its innermost set of arguments the EXTRA_ARGS. */
491 add_to_template_args (tree args, tree extra_args)
498 extra_depth = TMPL_ARGS_DEPTH (extra_args);
499 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
501 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
502 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
504 for (j = 1; j <= extra_depth; ++j, ++i)
505 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
510 /* Like add_to_template_args, but only the outermost ARGS are added to
511 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
512 (EXTRA_ARGS) levels are added. This function is used to combine
513 the template arguments from a partial instantiation with the
514 template arguments used to attain the full instantiation from the
515 partial instantiation. */
518 add_outermost_template_args (tree args, tree extra_args)
522 /* If there are more levels of EXTRA_ARGS than there are ARGS,
523 something very fishy is going on. */
524 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
526 /* If *all* the new arguments will be the EXTRA_ARGS, just return
528 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
531 /* For the moment, we make ARGS look like it contains fewer levels. */
532 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
534 new_args = add_to_template_args (args, extra_args);
536 /* Now, we restore ARGS to its full dimensions. */
537 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
542 /* Return the N levels of innermost template arguments from the ARGS. */
545 get_innermost_template_args (tree args, int n)
553 /* If N is 1, just return the innermost set of template arguments. */
555 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
557 /* If we're not removing anything, just return the arguments we were
559 extra_levels = TMPL_ARGS_DEPTH (args) - n;
560 gcc_assert (extra_levels >= 0);
561 if (extra_levels == 0)
564 /* Make a new set of arguments, not containing the outer arguments. */
565 new_args = make_tree_vec (n);
566 for (i = 1; i <= n; ++i)
567 SET_TMPL_ARGS_LEVEL (new_args, i,
568 TMPL_ARGS_LEVEL (args, i + extra_levels));
573 /* The inverse of get_innermost_template_args: Return all but the innermost
574 EXTRA_LEVELS levels of template arguments from the ARGS. */
577 strip_innermost_template_args (tree args, int extra_levels)
580 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
585 /* If N is 1, just return the outermost set of template arguments. */
587 return TMPL_ARGS_LEVEL (args, 1);
589 /* If we're not removing anything, just return the arguments we were
591 gcc_assert (extra_levels >= 0);
592 if (extra_levels == 0)
595 /* Make a new set of arguments, not containing the inner arguments. */
596 new_args = make_tree_vec (n);
597 for (i = 1; i <= n; ++i)
598 SET_TMPL_ARGS_LEVEL (new_args, i,
599 TMPL_ARGS_LEVEL (args, i));
604 /* We've got a template header coming up; push to a new level for storing
608 begin_template_parm_list (void)
610 /* We use a non-tag-transparent scope here, which causes pushtag to
611 put tags in this scope, rather than in the enclosing class or
612 namespace scope. This is the right thing, since we want
613 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
614 global template class, push_template_decl handles putting the
615 TEMPLATE_DECL into top-level scope. For a nested template class,
618 template <class T> struct S1 {
619 template <class T> struct S2 {};
622 pushtag contains special code to call pushdecl_with_scope on the
623 TEMPLATE_DECL for S2. */
624 begin_scope (sk_template_parms, NULL);
625 ++processing_template_decl;
626 ++processing_template_parmlist;
627 note_template_header (0);
630 /* This routine is called when a specialization is declared. If it is
631 invalid to declare a specialization here, an error is reported and
632 false is returned, otherwise this routine will return true. */
635 check_specialization_scope (void)
637 tree scope = current_scope ();
641 An explicit specialization shall be declared in the namespace of
642 which the template is a member, or, for member templates, in the
643 namespace of which the enclosing class or enclosing class
644 template is a member. An explicit specialization of a member
645 function, member class or static data member of a class template
646 shall be declared in the namespace of which the class template
648 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
650 error ("explicit specialization in non-namespace scope %qD", scope);
656 In an explicit specialization declaration for a member of a class
657 template or a member template that appears in namespace scope,
658 the member template and some of its enclosing class templates may
659 remain unspecialized, except that the declaration shall not
660 explicitly specialize a class member template if its enclosing
661 class templates are not explicitly specialized as well. */
662 if (current_template_parms)
664 error ("enclosing class templates are not explicitly specialized");
671 /* We've just seen template <>. */
674 begin_specialization (void)
676 begin_scope (sk_template_spec, NULL);
677 note_template_header (1);
678 return check_specialization_scope ();
681 /* Called at then end of processing a declaration preceded by
685 end_specialization (void)
688 reset_specialization ();
691 /* Any template <>'s that we have seen thus far are not referring to a
692 function specialization. */
695 reset_specialization (void)
697 processing_specialization = 0;
698 template_header_count = 0;
701 /* We've just seen a template header. If SPECIALIZATION is nonzero,
702 it was of the form template <>. */
705 note_template_header (int specialization)
707 processing_specialization = specialization;
708 template_header_count++;
711 /* We're beginning an explicit instantiation. */
714 begin_explicit_instantiation (void)
716 gcc_assert (!processing_explicit_instantiation);
717 processing_explicit_instantiation = true;
722 end_explicit_instantiation (void)
724 gcc_assert (processing_explicit_instantiation);
725 processing_explicit_instantiation = false;
728 /* An explicit specialization or partial specialization TMPL is being
729 declared. Check that the namespace in which the specialization is
730 occurring is permissible. Returns false iff it is invalid to
731 specialize TMPL in the current namespace. */
734 check_specialization_namespace (tree tmpl)
736 tree tpl_ns = decl_namespace_context (tmpl);
740 An explicit specialization shall be declared in the namespace of
741 which the template is a member, or, for member templates, in the
742 namespace of which the enclosing class or enclosing class
743 template is a member. An explicit specialization of a member
744 function, member class or static data member of a class template
745 shall be declared in the namespace of which the class template is
747 if (current_scope() != DECL_CONTEXT (tmpl)
748 && !at_namespace_scope_p ())
750 error ("specialization of %qD must appear at namespace scope", tmpl);
753 if (is_associated_namespace (current_namespace, tpl_ns))
754 /* Same or super-using namespace. */
758 permerror (input_location, "specialization of %qD in different namespace", tmpl);
759 permerror (input_location, " from definition of %q+#D", tmpl);
764 /* SPEC is an explicit instantiation. Check that it is valid to
765 perform this explicit instantiation in the current namespace. */
768 check_explicit_instantiation_namespace (tree spec)
772 /* DR 275: An explicit instantiation shall appear in an enclosing
773 namespace of its template. */
774 ns = decl_namespace_context (spec);
775 if (!is_ancestor (current_namespace, ns))
776 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
777 "(which does not enclose namespace %qD)",
778 spec, current_namespace, ns);
781 /* The TYPE is being declared. If it is a template type, that means it
782 is a partial specialization. Do appropriate error-checking. */
785 maybe_process_partial_specialization (tree type)
789 if (type == error_mark_node)
790 return error_mark_node;
792 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
794 error ("name of class shadows template template parameter %qD",
796 return error_mark_node;
799 context = TYPE_CONTEXT (type);
801 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
803 /* This is for ordinary explicit specialization and partial
804 specialization of a template class such as:
806 template <> class C<int>;
810 template <class T> class C<T*>;
812 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
814 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
815 && !COMPLETE_TYPE_P (type))
817 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
818 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
819 if (processing_template_decl)
821 if (push_template_decl (TYPE_MAIN_DECL (type))
823 return error_mark_node;
826 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
827 error ("specialization of %qT after instantiation", type);
829 else if (CLASS_TYPE_P (type)
830 && !CLASSTYPE_USE_TEMPLATE (type)
831 && CLASSTYPE_TEMPLATE_INFO (type)
832 && context && CLASS_TYPE_P (context)
833 && CLASSTYPE_TEMPLATE_INFO (context))
835 /* This is for an explicit specialization of member class
836 template according to [temp.expl.spec/18]:
838 template <> template <class U> class C<int>::D;
840 The context `C<int>' must be an implicit instantiation.
841 Otherwise this is just a member class template declared
844 template <> class C<int> { template <class U> class D; };
845 template <> template <class U> class C<int>::D;
847 In the first case, `C<int>::D' is a specialization of `C<T>::D'
848 while in the second case, `C<int>::D' is a primary template
849 and `C<T>::D' may not exist. */
851 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
852 && !COMPLETE_TYPE_P (type))
855 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
857 if (current_namespace
858 != decl_namespace_context (tmpl))
860 permerror (input_location, "specializing %q#T in different namespace", type);
861 permerror (input_location, " from definition of %q+#D", tmpl);
864 /* Check for invalid specialization after instantiation:
866 template <> template <> class C<int>::D<int>;
867 template <> template <class U> class C<int>::D; */
869 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
870 t; t = TREE_CHAIN (t))
872 tree inst = TREE_VALUE (t);
873 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
875 /* We already have a full specialization of this partial
876 instantiation. Reassign it to the new member
877 specialization template. */
881 elt.tmpl = most_general_template (tmpl);
882 elt.args = CLASSTYPE_TI_ARGS (inst);
885 htab_remove_elt (type_specializations, &elt);
888 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
890 slot = (spec_entry **)
891 htab_find_slot (type_specializations, &elt, INSERT);
892 *slot = GGC_NEW (spec_entry);
895 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
896 /* But if we've had an implicit instantiation, that's a
897 problem ([temp.expl.spec]/6). */
898 error ("specialization %qT after instantiation %qT",
902 /* Mark TYPE as a specialization. And as a result, we only
903 have one level of template argument for the innermost
905 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
906 CLASSTYPE_TI_ARGS (type)
907 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
910 else if (processing_specialization)
912 error ("explicit specialization of non-template %qT", type);
913 return error_mark_node;
919 /* Returns nonzero if we can optimize the retrieval of specializations
920 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
921 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
924 optimize_specialization_lookup_p (tree tmpl)
926 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
927 && DECL_CLASS_SCOPE_P (tmpl)
928 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
930 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
931 /* The optimized lookup depends on the fact that the
932 template arguments for the member function template apply
933 purely to the containing class, which is not true if the
934 containing class is an explicit or partial
936 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
937 && !DECL_MEMBER_TEMPLATE_P (tmpl)
938 && !DECL_CONV_FN_P (tmpl)
939 /* It is possible to have a template that is not a member
940 template and is not a member of a template class:
942 template <typename T>
943 struct S { friend A::f(); };
945 Here, the friend function is a template, but the context does
946 not have template information. The optimized lookup relies
947 on having ARGS be the template arguments for both the class
948 and the function template. */
949 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
952 /* Retrieve the specialization (in the sense of [temp.spec] - a
953 specialization is either an instantiation or an explicit
954 specialization) of TMPL for the given template ARGS. If there is
955 no such specialization, return NULL_TREE. The ARGS are a vector of
956 arguments, or a vector of vectors of arguments, in the case of
957 templates with more than one level of parameters.
959 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
960 then we search for a partial specialization matching ARGS. This
961 parameter is ignored if TMPL is not a class template. */
964 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
966 if (args == error_mark_node)
969 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
971 /* There should be as many levels of arguments as there are
972 levels of parameters. */
973 gcc_assert (TMPL_ARGS_DEPTH (args)
974 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
976 if (optimize_specialization_lookup_p (tmpl))
979 tree class_specialization;
980 VEC(tree,gc) *methods;
984 /* The template arguments actually apply to the containing
985 class. Find the class specialization with those
987 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
989 = retrieve_specialization (class_template, args, 0);
990 if (!class_specialization)
992 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
993 for the specialization. */
994 idx = class_method_index_for_fn (class_specialization, tmpl);
997 /* Iterate through the methods with the indicated name, looking
998 for the one that has an instance of TMPL. */
999 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1000 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1002 tree fn = OVL_CURRENT (fns);
1003 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1004 /* using-declarations can add base methods to the method vec,
1005 and we don't want those here. */
1006 && DECL_CONTEXT (fn) == class_specialization)
1015 htab_t specializations;
1019 elt.spec = NULL_TREE;
1021 if (DECL_CLASS_TEMPLATE_P (tmpl))
1022 specializations = type_specializations;
1024 specializations = decl_specializations;
1027 hash = hash_specialization (&elt);
1028 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1036 /* Like retrieve_specialization, but for local declarations. */
1039 retrieve_local_specialization (tree tmpl)
1043 if (local_specializations == NULL)
1046 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1047 htab_hash_pointer (tmpl));
1048 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1051 /* Returns nonzero iff DECL is a specialization of TMPL. */
1054 is_specialization_of (tree decl, tree tmpl)
1058 if (TREE_CODE (decl) == FUNCTION_DECL)
1062 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1068 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1070 for (t = TREE_TYPE (decl);
1072 t = CLASSTYPE_USE_TEMPLATE (t)
1073 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1074 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1081 /* Returns nonzero iff DECL is a specialization of friend declaration
1082 FRIEND_DECL according to [temp.friend]. */
1085 is_specialization_of_friend (tree decl, tree friend_decl)
1087 bool need_template = true;
1090 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1091 || TREE_CODE (decl) == TYPE_DECL);
1093 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1094 of a template class, we want to check if DECL is a specialization
1096 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1097 && DECL_TEMPLATE_INFO (friend_decl)
1098 && !DECL_USE_TEMPLATE (friend_decl))
1100 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1101 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1102 need_template = false;
1104 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1105 && !PRIMARY_TEMPLATE_P (friend_decl))
1106 need_template = false;
1108 /* There is nothing to do if this is not a template friend. */
1109 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1112 if (is_specialization_of (decl, friend_decl))
1116 A member of a class template may be declared to be a friend of a
1117 non-template class. In this case, the corresponding member of
1118 every specialization of the class template is a friend of the
1119 class granting friendship.
1121 For example, given a template friend declaration
1123 template <class T> friend void A<T>::f();
1125 the member function below is considered a friend
1127 template <> struct A<int> {
1131 For this type of template friend, TEMPLATE_DEPTH below will be
1132 nonzero. To determine if DECL is a friend of FRIEND, we first
1133 check if the enclosing class is a specialization of another. */
1135 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1137 && DECL_CLASS_SCOPE_P (decl)
1138 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1139 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1141 /* Next, we check the members themselves. In order to handle
1142 a few tricky cases, such as when FRIEND_DECL's are
1144 template <class T> friend void A<T>::g(T t);
1145 template <class T> template <T t> friend void A<T>::h();
1149 void A<int>::g(int);
1150 template <int> void A<int>::h();
1152 we need to figure out ARGS, the template arguments from
1153 the context of DECL. This is required for template substitution
1154 of `T' in the function parameter of `g' and template parameter
1155 of `h' in the above examples. Here ARGS corresponds to `int'. */
1157 tree context = DECL_CONTEXT (decl);
1158 tree args = NULL_TREE;
1159 int current_depth = 0;
1161 while (current_depth < template_depth)
1163 if (CLASSTYPE_TEMPLATE_INFO (context))
1165 if (current_depth == 0)
1166 args = TYPE_TI_ARGS (context);
1168 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1171 context = TYPE_CONTEXT (context);
1174 if (TREE_CODE (decl) == FUNCTION_DECL)
1179 tree friend_args_type;
1180 tree decl_args_type;
1182 /* Make sure that both DECL and FRIEND_DECL are templates or
1184 is_template = DECL_TEMPLATE_INFO (decl)
1185 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1186 if (need_template ^ is_template)
1188 else if (is_template)
1190 /* If both are templates, check template parameter list. */
1192 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1194 if (!comp_template_parms
1195 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1199 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1202 decl_type = TREE_TYPE (decl);
1204 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1205 tf_none, NULL_TREE);
1206 if (friend_type == error_mark_node)
1209 /* Check if return types match. */
1210 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1213 /* Check if function parameter types match, ignoring the
1214 `this' parameter. */
1215 friend_args_type = TYPE_ARG_TYPES (friend_type);
1216 decl_args_type = TYPE_ARG_TYPES (decl_type);
1217 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1218 friend_args_type = TREE_CHAIN (friend_args_type);
1219 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1220 decl_args_type = TREE_CHAIN (decl_args_type);
1222 return compparms (decl_args_type, friend_args_type);
1226 /* DECL is a TYPE_DECL */
1228 tree decl_type = TREE_TYPE (decl);
1230 /* Make sure that both DECL and FRIEND_DECL are templates or
1233 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1234 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1236 if (need_template ^ is_template)
1238 else if (is_template)
1241 /* If both are templates, check the name of the two
1242 TEMPLATE_DECL's first because is_friend didn't. */
1243 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1244 != DECL_NAME (friend_decl))
1247 /* Now check template parameter list. */
1249 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1251 return comp_template_parms
1252 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1256 return (DECL_NAME (decl)
1257 == DECL_NAME (friend_decl));
1263 /* Register the specialization SPEC as a specialization of TMPL with
1264 the indicated ARGS. IS_FRIEND indicates whether the specialization
1265 is actually just a friend declaration. Returns SPEC, or an
1266 equivalent prior declaration, if available. */
1269 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1273 spec_entry **slot = NULL;
1276 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1278 if (TREE_CODE (spec) == FUNCTION_DECL
1279 && uses_template_parms (DECL_TI_ARGS (spec)))
1280 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1281 register it; we want the corresponding TEMPLATE_DECL instead.
1282 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1283 the more obvious `uses_template_parms (spec)' to avoid problems
1284 with default function arguments. In particular, given
1285 something like this:
1287 template <class T> void f(T t1, T t = T())
1289 the default argument expression is not substituted for in an
1290 instantiation unless and until it is actually needed. */
1293 if (optimize_specialization_lookup_p (tmpl))
1294 /* We don't put these specializations in the hash table, but we might
1295 want to give an error about a mismatch. */
1296 fn = retrieve_specialization (tmpl, args, 0);
1304 hash = hash_specialization (&elt);
1306 slot = (spec_entry **)
1307 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1314 /* We can sometimes try to re-register a specialization that we've
1315 already got. In particular, regenerate_decl_from_template calls
1316 duplicate_decls which will update the specialization list. But,
1317 we'll still get called again here anyhow. It's more convenient
1318 to simply allow this than to try to prevent it. */
1321 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1323 if (DECL_TEMPLATE_INSTANTIATION (fn))
1325 if (DECL_ODR_USED (fn)
1326 || DECL_EXPLICIT_INSTANTIATION (fn))
1328 error ("specialization of %qD after instantiation",
1330 return error_mark_node;
1335 /* This situation should occur only if the first
1336 specialization is an implicit instantiation, the
1337 second is an explicit specialization, and the
1338 implicit instantiation has not yet been used. That
1339 situation can occur if we have implicitly
1340 instantiated a member function and then specialized
1343 We can also wind up here if a friend declaration that
1344 looked like an instantiation turns out to be a
1347 template <class T> void foo(T);
1348 class S { friend void foo<>(int) };
1349 template <> void foo(int);
1351 We transform the existing DECL in place so that any
1352 pointers to it become pointers to the updated
1355 If there was a definition for the template, but not
1356 for the specialization, we want this to look as if
1357 there were no definition, and vice versa. */
1358 DECL_INITIAL (fn) = NULL_TREE;
1359 duplicate_decls (spec, fn, is_friend);
1360 /* The call to duplicate_decls will have applied
1363 An explicit specialization of a function template
1364 is inline only if it is explicitly declared to be,
1365 and independently of whether its function template
1368 to the primary function; now copy the inline bits to
1369 the various clones. */
1370 FOR_EACH_CLONE (clone, fn)
1372 DECL_DECLARED_INLINE_P (clone)
1373 = DECL_DECLARED_INLINE_P (fn);
1374 DECL_SOURCE_LOCATION (clone)
1375 = DECL_SOURCE_LOCATION (fn);
1377 check_specialization_namespace (fn);
1382 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1384 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1385 /* Dup decl failed, but this is a new definition. Set the
1386 line number so any errors match this new
1388 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1394 return duplicate_decls (spec, fn, is_friend);
1396 /* A specialization must be declared in the same namespace as the
1397 template it is specializing. */
1398 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1399 && !check_specialization_namespace (tmpl))
1400 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1402 if (!optimize_specialization_lookup_p (tmpl))
1404 gcc_assert (tmpl && args && spec);
1405 *slot = GGC_NEW (spec_entry);
1407 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1408 && PRIMARY_TEMPLATE_P (tmpl)
1409 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1410 /* TMPL is a forward declaration of a template function; keep a list
1411 of all specializations in case we need to reassign them to a friend
1412 template later in tsubst_friend_function. */
1413 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1414 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1420 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1421 TMPL and ARGS members, ignores SPEC. */
1424 eq_specializations (const void *p1, const void *p2)
1426 const spec_entry *e1 = (const spec_entry *)p1;
1427 const spec_entry *e2 = (const spec_entry *)p2;
1429 return (e1->tmpl == e2->tmpl
1430 && comp_template_args (e1->args, e2->args));
1433 /* Returns a hash for a template TMPL and template arguments ARGS. */
1436 hash_tmpl_and_args (tree tmpl, tree args)
1438 hashval_t val = DECL_UID (tmpl);
1439 return iterative_hash_template_arg (args, val);
1442 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1446 hash_specialization (const void *p)
1448 const spec_entry *e = (const spec_entry *)p;
1449 return hash_tmpl_and_args (e->tmpl, e->args);
1452 /* Recursively calculate a hash value for a template argument ARG, for use
1453 in the hash tables of template specializations. */
1456 iterative_hash_template_arg (tree arg, hashval_t val)
1458 unsigned HOST_WIDE_INT i;
1459 enum tree_code code;
1462 if (arg == NULL_TREE)
1463 return iterative_hash_object (arg, val);
1468 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1469 /* We can get one of these when re-hashing a previous entry in the middle
1470 of substituting into a pack expansion. Just look through it. */
1471 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1473 code = TREE_CODE (arg);
1474 tclass = TREE_CODE_CLASS (code);
1476 val = iterative_hash_object (code, val);
1483 case IDENTIFIER_NODE:
1484 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1488 int i, len = TREE_VEC_LENGTH (arg);
1489 for (i = 0; i < len; ++i)
1490 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1494 case TYPE_PACK_EXPANSION:
1495 case EXPR_PACK_EXPANSION:
1496 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1498 case TYPE_ARGUMENT_PACK:
1499 case NONTYPE_ARGUMENT_PACK:
1500 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1503 for (; arg; arg = TREE_CHAIN (arg))
1504 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1508 for (; arg; arg = OVL_CHAIN (arg))
1509 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1515 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1517 val = iterative_hash_template_arg (field, val);
1518 val = iterative_hash_template_arg (value, val);
1524 if (!DECL_ARTIFICIAL (arg))
1525 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1526 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1529 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1532 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1533 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1535 case TEMPLATE_PARM_INDEX:
1536 val = iterative_hash_template_arg
1537 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1538 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1539 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1542 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1543 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1544 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1547 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1549 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1553 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1554 code = TREE_CODE (TREE_OPERAND (arg, 1));
1555 val = iterative_hash_object (code, val);
1556 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1559 /* layout_type sets structural equality for arrays of
1560 incomplete type, so we can't rely on the canonical type
1562 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1563 return iterative_hash_template_arg (TYPE_DOMAIN (arg), val);
1569 if (TYPE_CANONICAL (arg))
1570 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1572 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1573 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1574 /* Otherwise just compare the types during lookup. */
1577 case tcc_declaration:
1579 return iterative_hash_expr (arg, val);
1582 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1584 unsigned n = TREE_OPERAND_LENGTH (arg);
1585 for (i = 0; i < n; ++i)
1586 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1595 /* Unregister the specialization SPEC as a specialization of TMPL.
1596 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1597 if the SPEC was listed as a specialization of TMPL.
1599 Note that SPEC has been ggc_freed, so we can't look inside it. */
1602 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1607 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1608 elt.args = TI_ARGS (tinfo);
1609 elt.spec = NULL_TREE;
1611 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1614 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1615 gcc_assert (new_spec != NULL_TREE);
1616 (*slot)->spec = new_spec;
1623 /* Compare an entry in the local specializations hash table P1 (which
1624 is really a pointer to a TREE_LIST) with P2 (which is really a
1628 eq_local_specializations (const void *p1, const void *p2)
1630 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1633 /* Hash P1, an entry in the local specializations table. */
1636 hash_local_specialization (const void* p1)
1638 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1641 /* Like register_specialization, but for local declarations. We are
1642 registering SPEC, an instantiation of TMPL. */
1645 register_local_specialization (tree spec, tree tmpl)
1649 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1650 htab_hash_pointer (tmpl), INSERT);
1651 *slot = build_tree_list (spec, tmpl);
1654 /* TYPE is a class type. Returns true if TYPE is an explicitly
1655 specialized class. */
1658 explicit_class_specialization_p (tree type)
1660 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1662 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1665 /* Print the list of functions at FNS, going through all the overloads
1666 for each element of the list. Alternatively, FNS can not be a
1667 TREE_LIST, in which case it will be printed together with all the
1670 MORE and *STR should respectively be FALSE and NULL when the function
1671 is called from the outside. They are used internally on recursive
1672 calls. print_candidates manages the two parameters and leaves NULL
1673 in *STR when it ends. */
1676 print_candidates_1 (tree fns, bool more, const char **str)
1679 char *spaces = NULL;
1681 for (fn = fns; fn; fn = OVL_NEXT (fn))
1682 if (TREE_CODE (fn) == TREE_LIST)
1684 gcc_assert (!OVL_NEXT (fn) && !is_overloaded_fn (fn));
1685 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1686 print_candidates_1 (TREE_VALUE (fn2),
1687 TREE_CHAIN (fn2) || more, str);
1693 /* Pick the prefix string. */
1694 if (!more && !OVL_NEXT (fns))
1696 error ("candidate is: %+#D", OVL_CURRENT (fn));
1700 *str = _("candidates are:");
1701 spaces = get_spaces (*str);
1703 error ("%s %+#D", *str, OVL_CURRENT (fn));
1704 *str = spaces ? spaces : *str;
1714 /* Print the list of candidate FNS in an error message. */
1717 print_candidates (tree fns)
1719 const char *str = NULL;
1720 print_candidates_1 (fns, false, &str);
1721 gcc_assert (str == NULL);
1724 /* Returns the template (one of the functions given by TEMPLATE_ID)
1725 which can be specialized to match the indicated DECL with the
1726 explicit template args given in TEMPLATE_ID. The DECL may be
1727 NULL_TREE if none is available. In that case, the functions in
1728 TEMPLATE_ID are non-members.
1730 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1731 specialization of a member template.
1733 The TEMPLATE_COUNT is the number of references to qualifying
1734 template classes that appeared in the name of the function. See
1735 check_explicit_specialization for a more accurate description.
1737 TSK indicates what kind of template declaration (if any) is being
1738 declared. TSK_TEMPLATE indicates that the declaration given by
1739 DECL, though a FUNCTION_DECL, has template parameters, and is
1740 therefore a template function.
1742 The template args (those explicitly specified and those deduced)
1743 are output in a newly created vector *TARGS_OUT.
1745 If it is impossible to determine the result, an error message is
1746 issued. The error_mark_node is returned to indicate failure. */
1749 determine_specialization (tree template_id,
1752 int need_member_template,
1758 tree explicit_targs;
1759 tree candidates = NULL_TREE;
1760 /* A TREE_LIST of templates of which DECL may be a specialization.
1761 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1762 corresponding TREE_PURPOSE is the set of template arguments that,
1763 when used to instantiate the template, would produce a function
1764 with the signature of DECL. */
1765 tree templates = NULL_TREE;
1767 struct cp_binding_level *b;
1769 *targs_out = NULL_TREE;
1771 if (template_id == error_mark_node || decl == error_mark_node)
1772 return error_mark_node;
1774 fns = TREE_OPERAND (template_id, 0);
1775 explicit_targs = TREE_OPERAND (template_id, 1);
1777 if (fns == error_mark_node)
1778 return error_mark_node;
1780 /* Check for baselinks. */
1781 if (BASELINK_P (fns))
1782 fns = BASELINK_FUNCTIONS (fns);
1784 if (!is_overloaded_fn (fns))
1786 error ("%qD is not a function template", fns);
1787 return error_mark_node;
1790 /* Count the number of template headers specified for this
1793 for (b = current_binding_level;
1794 b->kind == sk_template_parms;
1798 for (; fns; fns = OVL_NEXT (fns))
1800 tree fn = OVL_CURRENT (fns);
1802 if (TREE_CODE (fn) == TEMPLATE_DECL)
1804 tree decl_arg_types;
1807 /* In case of explicit specialization, we need to check if
1808 the number of template headers appearing in the specialization
1809 is correct. This is usually done in check_explicit_specialization,
1810 but the check done there cannot be exhaustive when specializing
1811 member functions. Consider the following code:
1813 template <> void A<int>::f(int);
1814 template <> template <> void A<int>::f(int);
1816 Assuming that A<int> is not itself an explicit specialization
1817 already, the first line specializes "f" which is a non-template
1818 member function, whilst the second line specializes "f" which
1819 is a template member function. So both lines are syntactically
1820 correct, and check_explicit_specialization does not reject
1823 Here, we can do better, as we are matching the specialization
1824 against the declarations. We count the number of template
1825 headers, and we check if they match TEMPLATE_COUNT + 1
1826 (TEMPLATE_COUNT is the number of qualifying template classes,
1827 plus there must be another header for the member template
1830 Notice that if header_count is zero, this is not a
1831 specialization but rather a template instantiation, so there
1832 is no check we can perform here. */
1833 if (header_count && header_count != template_count + 1)
1836 /* Check that the number of template arguments at the
1837 innermost level for DECL is the same as for FN. */
1838 if (current_binding_level->kind == sk_template_parms
1839 && !current_binding_level->explicit_spec_p
1840 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1841 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1842 (current_template_parms))))
1845 /* DECL might be a specialization of FN. */
1846 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1847 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1849 /* For a non-static member function, we need to make sure
1850 that the const qualification is the same. Since
1851 get_bindings does not try to merge the "this" parameter,
1852 we must do the comparison explicitly. */
1853 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1854 && !same_type_p (TREE_VALUE (fn_arg_types),
1855 TREE_VALUE (decl_arg_types)))
1858 /* Skip the "this" parameter and, for constructors of
1859 classes with virtual bases, the VTT parameter. A
1860 full specialization of a constructor will have a VTT
1861 parameter, but a template never will. */
1863 = skip_artificial_parms_for (decl, decl_arg_types);
1865 = skip_artificial_parms_for (fn, fn_arg_types);
1867 /* Check that the number of function parameters matches.
1869 template <class T> void f(int i = 0);
1870 template <> void f<int>();
1871 The specialization f<int> is invalid but is not caught
1872 by get_bindings below. */
1873 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1876 /* Function templates cannot be specializations; there are
1877 no partial specializations of functions. Therefore, if
1878 the type of DECL does not match FN, there is no
1880 if (tsk == tsk_template)
1882 if (compparms (fn_arg_types, decl_arg_types))
1883 candidates = tree_cons (NULL_TREE, fn, candidates);
1887 /* See whether this function might be a specialization of this
1889 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1892 /* We cannot deduce template arguments that when used to
1893 specialize TMPL will produce DECL. */
1896 /* Save this template, and the arguments deduced. */
1897 templates = tree_cons (targs, fn, templates);
1899 else if (need_member_template)
1900 /* FN is an ordinary member function, and we need a
1901 specialization of a member template. */
1903 else if (TREE_CODE (fn) != FUNCTION_DECL)
1904 /* We can get IDENTIFIER_NODEs here in certain erroneous
1907 else if (!DECL_FUNCTION_MEMBER_P (fn))
1908 /* This is just an ordinary non-member function. Nothing can
1909 be a specialization of that. */
1911 else if (DECL_ARTIFICIAL (fn))
1912 /* Cannot specialize functions that are created implicitly. */
1916 tree decl_arg_types;
1918 /* This is an ordinary member function. However, since
1919 we're here, we can assume it's enclosing class is a
1920 template class. For example,
1922 template <typename T> struct S { void f(); };
1923 template <> void S<int>::f() {}
1925 Here, S<int>::f is a non-template, but S<int> is a
1926 template class. If FN has the same type as DECL, we
1927 might be in business. */
1929 if (!DECL_TEMPLATE_INFO (fn))
1930 /* Its enclosing class is an explicit specialization
1931 of a template class. This is not a candidate. */
1934 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1935 TREE_TYPE (TREE_TYPE (fn))))
1936 /* The return types differ. */
1939 /* Adjust the type of DECL in case FN is a static member. */
1940 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1941 if (DECL_STATIC_FUNCTION_P (fn)
1942 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1943 decl_arg_types = TREE_CHAIN (decl_arg_types);
1945 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1948 candidates = tree_cons (NULL_TREE, fn, candidates);
1952 if (templates && TREE_CHAIN (templates))
1958 It is possible for a specialization with a given function
1959 signature to be instantiated from more than one function
1960 template. In such cases, explicit specification of the
1961 template arguments must be used to uniquely identify the
1962 function template specialization being specialized.
1964 Note that here, there's no suggestion that we're supposed to
1965 determine which of the candidate templates is most
1966 specialized. However, we, also have:
1970 Partial ordering of overloaded function template
1971 declarations is used in the following contexts to select
1972 the function template to which a function template
1973 specialization refers:
1975 -- when an explicit specialization refers to a function
1978 So, we do use the partial ordering rules, at least for now.
1979 This extension can only serve to make invalid programs valid,
1980 so it's safe. And, there is strong anecdotal evidence that
1981 the committee intended the partial ordering rules to apply;
1982 the EDG front end has that behavior, and John Spicer claims
1983 that the committee simply forgot to delete the wording in
1984 [temp.expl.spec]. */
1985 tree tmpl = most_specialized_instantiation (templates);
1986 if (tmpl != error_mark_node)
1989 TREE_CHAIN (templates) = NULL_TREE;
1993 if (templates == NULL_TREE && candidates == NULL_TREE)
1995 error ("template-id %qD for %q+D does not match any template "
1996 "declaration", template_id, decl);
1997 if (header_count && header_count != template_count + 1)
1998 inform (input_location, "saw %d %<template<>%>, need %d for "
1999 "specializing a member function template",
2000 header_count, template_count + 1);
2001 return error_mark_node;
2003 else if ((templates && TREE_CHAIN (templates))
2004 || (candidates && TREE_CHAIN (candidates))
2005 || (templates && candidates))
2007 error ("ambiguous template specialization %qD for %q+D",
2009 candidates = chainon (candidates, templates);
2010 print_candidates (candidates);
2011 return error_mark_node;
2014 /* We have one, and exactly one, match. */
2017 tree fn = TREE_VALUE (candidates);
2018 *targs_out = copy_node (DECL_TI_ARGS (fn));
2019 /* DECL is a re-declaration or partial instantiation of a template
2021 if (TREE_CODE (fn) == TEMPLATE_DECL)
2023 /* It was a specialization of an ordinary member function in a
2025 return DECL_TI_TEMPLATE (fn);
2028 /* It was a specialization of a template. */
2029 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2030 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2032 *targs_out = copy_node (targs);
2033 SET_TMPL_ARGS_LEVEL (*targs_out,
2034 TMPL_ARGS_DEPTH (*targs_out),
2035 TREE_PURPOSE (templates));
2038 *targs_out = TREE_PURPOSE (templates);
2039 return TREE_VALUE (templates);
2042 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2043 but with the default argument values filled in from those in the
2047 copy_default_args_to_explicit_spec_1 (tree spec_types,
2050 tree new_spec_types;
2055 if (spec_types == void_list_node)
2056 return void_list_node;
2058 /* Substitute into the rest of the list. */
2060 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2061 TREE_CHAIN (tmpl_types));
2063 /* Add the default argument for this parameter. */
2064 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2065 TREE_VALUE (spec_types),
2069 /* DECL is an explicit specialization. Replicate default arguments
2070 from the template it specializes. (That way, code like:
2072 template <class T> void f(T = 3);
2073 template <> void f(double);
2076 works, as required.) An alternative approach would be to look up
2077 the correct default arguments at the call-site, but this approach
2078 is consistent with how implicit instantiations are handled. */
2081 copy_default_args_to_explicit_spec (tree decl)
2086 tree new_spec_types;
2090 tree object_type = NULL_TREE;
2091 tree in_charge = NULL_TREE;
2092 tree vtt = NULL_TREE;
2094 /* See if there's anything we need to do. */
2095 tmpl = DECL_TI_TEMPLATE (decl);
2096 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2097 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2098 if (TREE_PURPOSE (t))
2103 old_type = TREE_TYPE (decl);
2104 spec_types = TYPE_ARG_TYPES (old_type);
2106 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2108 /* Remove the this pointer, but remember the object's type for
2110 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2111 spec_types = TREE_CHAIN (spec_types);
2112 tmpl_types = TREE_CHAIN (tmpl_types);
2114 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2116 /* DECL may contain more parameters than TMPL due to the extra
2117 in-charge parameter in constructors and destructors. */
2118 in_charge = spec_types;
2119 spec_types = TREE_CHAIN (spec_types);
2121 if (DECL_HAS_VTT_PARM_P (decl))
2124 spec_types = TREE_CHAIN (spec_types);
2128 /* Compute the merged default arguments. */
2130 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2132 /* Compute the new FUNCTION_TYPE. */
2136 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2141 /* Put the in-charge parameter back. */
2142 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2143 TREE_VALUE (in_charge),
2146 new_type = build_method_type_directly (object_type,
2147 TREE_TYPE (old_type),
2151 new_type = build_function_type (TREE_TYPE (old_type),
2153 new_type = cp_build_type_attribute_variant (new_type,
2154 TYPE_ATTRIBUTES (old_type));
2155 new_type = build_exception_variant (new_type,
2156 TYPE_RAISES_EXCEPTIONS (old_type));
2157 TREE_TYPE (decl) = new_type;
2160 /* Check to see if the function just declared, as indicated in
2161 DECLARATOR, and in DECL, is a specialization of a function
2162 template. We may also discover that the declaration is an explicit
2163 instantiation at this point.
2165 Returns DECL, or an equivalent declaration that should be used
2166 instead if all goes well. Issues an error message if something is
2167 amiss. Returns error_mark_node if the error is not easily
2170 FLAGS is a bitmask consisting of the following flags:
2172 2: The function has a definition.
2173 4: The function is a friend.
2175 The TEMPLATE_COUNT is the number of references to qualifying
2176 template classes that appeared in the name of the function. For
2179 template <class T> struct S { void f(); };
2182 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2183 classes are not counted in the TEMPLATE_COUNT, so that in
2185 template <class T> struct S {};
2186 template <> struct S<int> { void f(); }
2187 template <> void S<int>::f();
2189 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2190 invalid; there should be no template <>.)
2192 If the function is a specialization, it is marked as such via
2193 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2194 is set up correctly, and it is added to the list of specializations
2195 for that template. */
2198 check_explicit_specialization (tree declarator,
2203 int have_def = flags & 2;
2204 int is_friend = flags & 4;
2205 int specialization = 0;
2206 int explicit_instantiation = 0;
2207 int member_specialization = 0;
2208 tree ctype = DECL_CLASS_CONTEXT (decl);
2209 tree dname = DECL_NAME (decl);
2214 if (!processing_specialization)
2217 tsk = tsk_excessive_parms;
2220 tsk = current_tmpl_spec_kind (template_count);
2225 if (processing_specialization)
2228 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2230 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2233 /* This could be something like:
2235 template <class T> void f(T);
2236 class S { friend void f<>(int); } */
2240 /* This case handles bogus declarations like template <>
2241 template <class T> void f<int>(); */
2243 error ("template-id %qD in declaration of primary template",
2250 case tsk_invalid_member_spec:
2251 /* The error has already been reported in
2252 check_specialization_scope. */
2253 return error_mark_node;
2255 case tsk_invalid_expl_inst:
2256 error ("template parameter list used in explicit instantiation");
2262 error ("definition provided for explicit instantiation");
2264 explicit_instantiation = 1;
2267 case tsk_excessive_parms:
2268 case tsk_insufficient_parms:
2269 if (tsk == tsk_excessive_parms)
2270 error ("too many template parameter lists in declaration of %qD",
2272 else if (template_header_count)
2273 error("too few template parameter lists in declaration of %qD", decl);
2275 error("explicit specialization of %qD must be introduced by "
2276 "%<template <>%>", decl);
2280 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2282 member_specialization = 1;
2288 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2290 /* This case handles bogus declarations like template <>
2291 template <class T> void f<int>(); */
2293 if (uses_template_parms (declarator))
2294 error ("function template partial specialization %qD "
2295 "is not allowed", declarator);
2297 error ("template-id %qD in declaration of primary template",
2302 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2303 /* This is a specialization of a member template, without
2304 specialization the containing class. Something like:
2306 template <class T> struct S {
2307 template <class U> void f (U);
2309 template <> template <class U> void S<int>::f(U) {}
2311 That's a specialization -- but of the entire template. */
2319 if (specialization || member_specialization)
2321 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2322 for (; t; t = TREE_CHAIN (t))
2323 if (TREE_PURPOSE (t))
2325 permerror (input_location,
2326 "default argument specified in explicit specialization");
2331 if (specialization || member_specialization || explicit_instantiation)
2333 tree tmpl = NULL_TREE;
2334 tree targs = NULL_TREE;
2336 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2337 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2341 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2346 /* If there is no class context, the explicit instantiation
2347 must be at namespace scope. */
2348 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2350 /* Find the namespace binding, using the declaration
2352 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2354 if (fns == error_mark_node || !is_overloaded_fn (fns))
2356 error ("%qD is not a template function", dname);
2357 fns = error_mark_node;
2361 tree fn = OVL_CURRENT (fns);
2362 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2363 CP_DECL_CONTEXT (fn)))
2364 error ("%qD is not declared in %qD",
2365 decl, current_namespace);
2369 declarator = lookup_template_function (fns, NULL_TREE);
2372 if (declarator == error_mark_node)
2373 return error_mark_node;
2375 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2377 if (!explicit_instantiation)
2378 /* A specialization in class scope. This is invalid,
2379 but the error will already have been flagged by
2380 check_specialization_scope. */
2381 return error_mark_node;
2384 /* It's not valid to write an explicit instantiation in
2387 class C { template void f(); }
2389 This case is caught by the parser. However, on
2392 template class C { void f(); };
2394 (which is invalid) we can get here. The error will be
2401 else if (ctype != NULL_TREE
2402 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2405 /* Find the list of functions in ctype that have the same
2406 name as the declared function. */
2407 tree name = TREE_OPERAND (declarator, 0);
2408 tree fns = NULL_TREE;
2411 if (constructor_name_p (name, ctype))
2413 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2415 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2416 : !CLASSTYPE_DESTRUCTORS (ctype))
2418 /* From [temp.expl.spec]:
2420 If such an explicit specialization for the member
2421 of a class template names an implicitly-declared
2422 special member function (clause _special_), the
2423 program is ill-formed.
2425 Similar language is found in [temp.explicit]. */
2426 error ("specialization of implicitly-declared special member function");
2427 return error_mark_node;
2430 name = is_constructor ? ctor_identifier : dtor_identifier;
2433 if (!DECL_CONV_FN_P (decl))
2435 idx = lookup_fnfields_1 (ctype, name);
2437 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2441 VEC(tree,gc) *methods;
2444 /* For a type-conversion operator, we cannot do a
2445 name-based lookup. We might be looking for `operator
2446 int' which will be a specialization of `operator T'.
2447 So, we find *all* the conversion operators, and then
2448 select from them. */
2451 methods = CLASSTYPE_METHOD_VEC (ctype);
2453 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2454 VEC_iterate (tree, methods, idx, ovl);
2457 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2458 /* There are no more conversion functions. */
2461 /* Glue all these conversion functions together
2462 with those we already have. */
2463 for (; ovl; ovl = OVL_NEXT (ovl))
2464 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2468 if (fns == NULL_TREE)
2470 error ("no member function %qD declared in %qT", name, ctype);
2471 return error_mark_node;
2474 TREE_OPERAND (declarator, 0) = fns;
2477 /* Figure out what exactly is being specialized at this point.
2478 Note that for an explicit instantiation, even one for a
2479 member function, we cannot tell apriori whether the
2480 instantiation is for a member template, or just a member
2481 function of a template class. Even if a member template is
2482 being instantiated, the member template arguments may be
2483 elided if they can be deduced from the rest of the
2485 tmpl = determine_specialization (declarator, decl,
2487 member_specialization,
2491 if (!tmpl || tmpl == error_mark_node)
2492 /* We couldn't figure out what this declaration was
2494 return error_mark_node;
2497 tree gen_tmpl = most_general_template (tmpl);
2499 if (explicit_instantiation)
2501 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2502 is done by do_decl_instantiation later. */
2504 int arg_depth = TMPL_ARGS_DEPTH (targs);
2505 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2507 if (arg_depth > parm_depth)
2509 /* If TMPL is not the most general template (for
2510 example, if TMPL is a friend template that is
2511 injected into namespace scope), then there will
2512 be too many levels of TARGS. Remove some of them
2517 new_targs = make_tree_vec (parm_depth);
2518 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2519 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2520 = TREE_VEC_ELT (targs, i);
2524 return instantiate_template (tmpl, targs, tf_error);
2527 /* If we thought that the DECL was a member function, but it
2528 turns out to be specializing a static member function,
2529 make DECL a static member function as well. */
2530 if (DECL_STATIC_FUNCTION_P (tmpl)
2531 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2532 revert_static_member_fn (decl);
2534 /* If this is a specialization of a member template of a
2535 template class, we want to return the TEMPLATE_DECL, not
2536 the specialization of it. */
2537 if (tsk == tsk_template)
2539 tree result = DECL_TEMPLATE_RESULT (tmpl);
2540 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2541 DECL_INITIAL (result) = NULL_TREE;
2545 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2546 DECL_SOURCE_LOCATION (result)
2547 = DECL_SOURCE_LOCATION (decl);
2548 /* We want to use the argument list specified in the
2549 definition, not in the original declaration. */
2550 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2551 for (parm = DECL_ARGUMENTS (result); parm;
2552 parm = TREE_CHAIN (parm))
2553 DECL_CONTEXT (parm) = result;
2555 return register_specialization (tmpl, gen_tmpl, targs,
2559 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2560 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2562 /* Inherit default function arguments from the template
2563 DECL is specializing. */
2564 copy_default_args_to_explicit_spec (decl);
2566 /* This specialization has the same protection as the
2567 template it specializes. */
2568 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2569 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2571 /* 7.1.1-1 [dcl.stc]
2573 A storage-class-specifier shall not be specified in an
2574 explicit specialization...
2576 The parser rejects these, so unless action is taken here,
2577 explicit function specializations will always appear with
2580 The action recommended by the C++ CWG in response to C++
2581 defect report 605 is to make the storage class and linkage
2582 of the explicit specialization match the templated function:
2584 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2586 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2588 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2589 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2591 /* This specialization has the same linkage and visibility as
2592 the function template it specializes. */
2593 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2594 if (! TREE_PUBLIC (decl))
2596 DECL_INTERFACE_KNOWN (decl) = 1;
2597 DECL_NOT_REALLY_EXTERN (decl) = 1;
2599 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2600 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2602 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2603 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2607 /* If DECL is a friend declaration, declared using an
2608 unqualified name, the namespace associated with DECL may
2609 have been set incorrectly. For example, in:
2611 template <typename T> void f(T);
2613 struct S { friend void f<int>(int); }
2616 we will have set the DECL_CONTEXT for the friend
2617 declaration to N, rather than to the global namespace. */
2618 if (DECL_NAMESPACE_SCOPE_P (decl))
2619 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2621 if (is_friend && !have_def)
2622 /* This is not really a declaration of a specialization.
2623 It's just the name of an instantiation. But, it's not
2624 a request for an instantiation, either. */
2625 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2626 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2627 /* This is indeed a specialization. In case of constructors
2628 and destructors, we need in-charge and not-in-charge
2629 versions in V3 ABI. */
2630 clone_function_decl (decl, /*update_method_vec_p=*/0);
2632 /* Register this specialization so that we can find it
2634 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2641 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2642 parameters. These are represented in the same format used for
2643 DECL_TEMPLATE_PARMS. */
2646 comp_template_parms (const_tree parms1, const_tree parms2)
2651 if (parms1 == parms2)
2654 for (p1 = parms1, p2 = parms2;
2655 p1 != NULL_TREE && p2 != NULL_TREE;
2656 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2658 tree t1 = TREE_VALUE (p1);
2659 tree t2 = TREE_VALUE (p2);
2662 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2663 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2665 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2668 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2670 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2671 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2673 /* If either of the template parameters are invalid, assume
2674 they match for the sake of error recovery. */
2675 if (parm1 == error_mark_node || parm2 == error_mark_node)
2678 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2681 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2682 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2683 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2685 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2690 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2691 /* One set of parameters has more parameters lists than the
2698 /* Determine whether PARM is a parameter pack. */
2701 template_parameter_pack_p (const_tree parm)
2703 /* Determine if we have a non-type template parameter pack. */
2704 if (TREE_CODE (parm) == PARM_DECL)
2705 return (DECL_TEMPLATE_PARM_P (parm)
2706 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2708 /* If this is a list of template parameters, we could get a
2709 TYPE_DECL or a TEMPLATE_DECL. */
2710 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2711 parm = TREE_TYPE (parm);
2713 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2714 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2715 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2718 /* Determine if T is a function parameter pack. */
2721 function_parameter_pack_p (const_tree t)
2723 if (t && TREE_CODE (t) == PARM_DECL)
2724 return FUNCTION_PARAMETER_PACK_P (t);
2728 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2729 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2732 get_function_template_decl (const_tree primary_func_tmpl_inst)
2734 if (! primary_func_tmpl_inst
2735 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2736 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2739 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2742 /* Return true iff the function parameter PARAM_DECL was expanded
2743 from the function parameter pack PACK. */
2746 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2748 if (DECL_ARTIFICIAL (param_decl)
2749 || !function_parameter_pack_p (pack))
2752 /* The parameter pack and its pack arguments have the same
2754 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2757 /* Determine whether ARGS describes a variadic template args list,
2758 i.e., one that is terminated by a template argument pack. */
2761 template_args_variadic_p (tree args)
2766 if (args == NULL_TREE)
2769 args = INNERMOST_TEMPLATE_ARGS (args);
2770 nargs = TREE_VEC_LENGTH (args);
2775 last_parm = TREE_VEC_ELT (args, nargs - 1);
2777 return ARGUMENT_PACK_P (last_parm);
2780 /* Generate a new name for the parameter pack name NAME (an
2781 IDENTIFIER_NODE) that incorporates its */
2784 make_ith_pack_parameter_name (tree name, int i)
2786 /* Munge the name to include the parameter index. */
2787 #define NUMBUF_LEN 128
2788 char numbuf[NUMBUF_LEN];
2792 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2793 newname_len = IDENTIFIER_LENGTH (name)
2794 + strlen (numbuf) + 2;
2795 newname = (char*)alloca (newname_len);
2796 snprintf (newname, newname_len,
2797 "%s#%i", IDENTIFIER_POINTER (name), i);
2798 return get_identifier (newname);
2801 /* Return true if T is a primary function
2802 or class template instantiation. */
2805 primary_template_instantiation_p (const_tree t)
2810 if (TREE_CODE (t) == FUNCTION_DECL)
2811 return DECL_LANG_SPECIFIC (t)
2812 && DECL_TEMPLATE_INSTANTIATION (t)
2813 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2814 else if (CLASS_TYPE_P (t))
2815 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2816 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2820 /* Return true if PARM is a template template parameter. */
2823 template_template_parameter_p (const_tree parm)
2825 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2828 /* Return the template parameters of T if T is a
2829 primary template instantiation, NULL otherwise. */
2832 get_primary_template_innermost_parameters (const_tree t)
2834 tree parms = NULL, template_info = NULL;
2836 if ((template_info = get_template_info (t))
2837 && primary_template_instantiation_p (t))
2838 parms = INNERMOST_TEMPLATE_PARMS
2839 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2844 /* Returns the template arguments of T if T is a template instantiation,
2848 get_template_innermost_arguments (const_tree t)
2850 tree args = NULL, template_info = NULL;
2852 if ((template_info = get_template_info (t))
2853 && TI_ARGS (template_info))
2854 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2859 /* Return the argument pack elements of T if T is a template argument pack,
2863 get_template_argument_pack_elems (const_tree t)
2865 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2866 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2869 return ARGUMENT_PACK_ARGS (t);
2872 /* Structure used to track the progress of find_parameter_packs_r. */
2873 struct find_parameter_pack_data
2875 /* TREE_LIST that will contain all of the parameter packs found by
2877 tree* parameter_packs;
2879 /* Set of AST nodes that have been visited by the traversal. */
2880 struct pointer_set_t *visited;
2883 /* Identifies all of the argument packs that occur in a template
2884 argument and appends them to the TREE_LIST inside DATA, which is a
2885 find_parameter_pack_data structure. This is a subroutine of
2886 make_pack_expansion and uses_parameter_packs. */
2888 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2891 struct find_parameter_pack_data* ppd =
2892 (struct find_parameter_pack_data*)data;
2893 bool parameter_pack_p = false;
2895 /* Identify whether this is a parameter pack or not. */
2896 switch (TREE_CODE (t))
2898 case TEMPLATE_PARM_INDEX:
2899 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2900 parameter_pack_p = true;
2903 case TEMPLATE_TYPE_PARM:
2904 case TEMPLATE_TEMPLATE_PARM:
2905 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2906 parameter_pack_p = true;
2910 if (FUNCTION_PARAMETER_PACK_P (t))
2912 /* We don't want to walk into the type of a PARM_DECL,
2913 because we don't want to see the type parameter pack. */
2915 parameter_pack_p = true;
2920 /* Not a parameter pack. */
2924 if (parameter_pack_p)
2926 /* Add this parameter pack to the list. */
2927 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2931 cp_walk_tree (&TYPE_CONTEXT (t),
2932 &find_parameter_packs_r, ppd, ppd->visited);
2934 /* This switch statement will return immediately if we don't find a
2936 switch (TREE_CODE (t))
2938 case TEMPLATE_PARM_INDEX:
2941 case BOUND_TEMPLATE_TEMPLATE_PARM:
2942 /* Check the template itself. */
2943 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2944 &find_parameter_packs_r, ppd, ppd->visited);
2945 /* Check the template arguments. */
2946 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2951 case TEMPLATE_TYPE_PARM:
2952 case TEMPLATE_TEMPLATE_PARM:
2959 if (TYPE_PTRMEMFUNC_P (t))
2965 if (TYPE_TEMPLATE_INFO (t))
2966 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
2967 &find_parameter_packs_r, ppd, ppd->visited);
2973 cp_walk_tree (&TREE_TYPE (t),
2974 &find_parameter_packs_r, ppd, ppd->visited);
2978 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2983 case TYPE_PACK_EXPANSION:
2984 case EXPR_PACK_EXPANSION:
2989 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2994 case IDENTIFIER_NODE:
2995 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3007 /* Determines if the expression or type T uses any parameter packs. */
3009 uses_parameter_packs (tree t)
3011 tree parameter_packs = NULL_TREE;
3012 struct find_parameter_pack_data ppd;
3013 ppd.parameter_packs = ¶meter_packs;
3014 ppd.visited = pointer_set_create ();
3015 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3016 pointer_set_destroy (ppd.visited);
3017 return parameter_packs != NULL_TREE;
3020 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3021 representation a base-class initializer into a parameter pack
3022 expansion. If all goes well, the resulting node will be an
3023 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3026 make_pack_expansion (tree arg)
3029 tree parameter_packs = NULL_TREE;
3030 bool for_types = false;
3031 struct find_parameter_pack_data ppd;
3033 if (!arg || arg == error_mark_node)
3036 if (TREE_CODE (arg) == TREE_LIST)
3038 /* The only time we will see a TREE_LIST here is for a base
3039 class initializer. In this case, the TREE_PURPOSE will be a
3040 _TYPE node (representing the base class expansion we're
3041 initializing) and the TREE_VALUE will be a TREE_LIST
3042 containing the initialization arguments.
3044 The resulting expansion looks somewhat different from most
3045 expansions. Rather than returning just one _EXPANSION, we
3046 return a TREE_LIST whose TREE_PURPOSE is a
3047 TYPE_PACK_EXPANSION containing the bases that will be
3048 initialized. The TREE_VALUE will be identical to the
3049 original TREE_VALUE, which is a list of arguments that will
3050 be passed to each base. We do not introduce any new pack
3051 expansion nodes into the TREE_VALUE (although it is possible
3052 that some already exist), because the TREE_PURPOSE and
3053 TREE_VALUE all need to be expanded together with the same
3054 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3055 resulting TREE_PURPOSE will mention the parameter packs in
3056 both the bases and the arguments to the bases. */
3059 tree parameter_packs = NULL_TREE;
3061 /* Determine which parameter packs will be used by the base
3063 ppd.visited = pointer_set_create ();
3064 ppd.parameter_packs = ¶meter_packs;
3065 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3068 if (parameter_packs == NULL_TREE)
3070 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3071 pointer_set_destroy (ppd.visited);
3072 return error_mark_node;
3075 if (TREE_VALUE (arg) != void_type_node)
3077 /* Collect the sets of parameter packs used in each of the
3078 initialization arguments. */
3079 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3081 /* Determine which parameter packs will be expanded in this
3083 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3088 pointer_set_destroy (ppd.visited);
3090 /* Create the pack expansion type for the base type. */
3091 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3092 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3093 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3095 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3096 they will rarely be compared to anything. */
3097 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3099 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3102 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3105 /* Build the PACK_EXPANSION_* node. */
3107 ? cxx_make_type (TYPE_PACK_EXPANSION)
3108 : make_node (EXPR_PACK_EXPANSION);
3109 SET_PACK_EXPANSION_PATTERN (result, arg);
3110 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3112 /* Propagate type and const-expression information. */
3113 TREE_TYPE (result) = TREE_TYPE (arg);
3114 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3117 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3118 they will rarely be compared to anything. */
3119 SET_TYPE_STRUCTURAL_EQUALITY (result);
3121 /* Determine which parameter packs will be expanded. */
3122 ppd.parameter_packs = ¶meter_packs;
3123 ppd.visited = pointer_set_create ();
3124 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3125 pointer_set_destroy (ppd.visited);
3127 /* Make sure we found some parameter packs. */
3128 if (parameter_packs == NULL_TREE)
3131 error ("expansion pattern %<%T%> contains no argument packs", arg);
3133 error ("expansion pattern %<%E%> contains no argument packs", arg);
3134 return error_mark_node;
3136 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3141 /* Checks T for any "bare" parameter packs, which have not yet been
3142 expanded, and issues an error if any are found. This operation can
3143 only be done on full expressions or types (e.g., an expression
3144 statement, "if" condition, etc.), because we could have expressions like:
3146 foo(f(g(h(args)))...)
3148 where "args" is a parameter pack. check_for_bare_parameter_packs
3149 should not be called for the subexpressions args, h(args),
3150 g(h(args)), or f(g(h(args))), because we would produce erroneous
3153 Returns TRUE and emits an error if there were bare parameter packs,
3154 returns FALSE otherwise. */
3156 check_for_bare_parameter_packs (tree t)
3158 tree parameter_packs = NULL_TREE;
3159 struct find_parameter_pack_data ppd;
3161 if (!processing_template_decl || !t || t == error_mark_node)
3164 if (TREE_CODE (t) == TYPE_DECL)
3167 ppd.parameter_packs = ¶meter_packs;
3168 ppd.visited = pointer_set_create ();
3169 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3170 pointer_set_destroy (ppd.visited);
3172 if (parameter_packs)
3174 error ("parameter packs not expanded with %<...%>:");
3175 while (parameter_packs)
3177 tree pack = TREE_VALUE (parameter_packs);
3178 tree name = NULL_TREE;
3180 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3181 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3182 name = TYPE_NAME (pack);
3183 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3184 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3186 name = DECL_NAME (pack);
3189 inform (input_location, " %qD", name);
3191 inform (input_location, " <anonymous>");
3193 parameter_packs = TREE_CHAIN (parameter_packs);
3202 /* Expand any parameter packs that occur in the template arguments in
3205 expand_template_argument_pack (tree args)
3207 tree result_args = NULL_TREE;
3208 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3209 int num_result_args = -1;
3210 int non_default_args_count = -1;
3212 /* First, determine if we need to expand anything, and the number of
3213 slots we'll need. */
3214 for (in_arg = 0; in_arg < nargs; ++in_arg)
3216 tree arg = TREE_VEC_ELT (args, in_arg);
3217 if (arg == NULL_TREE)
3219 if (ARGUMENT_PACK_P (arg))
3221 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3222 if (num_result_args < 0)
3223 num_result_args = in_arg + num_packed;
3225 num_result_args += num_packed;
3229 if (num_result_args >= 0)
3234 /* If no expansion is necessary, we're done. */
3235 if (num_result_args < 0)
3238 /* Expand arguments. */
3239 result_args = make_tree_vec (num_result_args);
3240 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3241 non_default_args_count =
3242 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3243 for (in_arg = 0; in_arg < nargs; ++in_arg)
3245 tree arg = TREE_VEC_ELT (args, in_arg);
3246 if (ARGUMENT_PACK_P (arg))
3248 tree packed = ARGUMENT_PACK_ARGS (arg);
3249 int i, num_packed = TREE_VEC_LENGTH (packed);
3250 for (i = 0; i < num_packed; ++i, ++out_arg)
3251 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3252 if (non_default_args_count > 0)
3253 non_default_args_count += num_packed;
3257 TREE_VEC_ELT (result_args, out_arg) = arg;
3261 if (non_default_args_count >= 0)
3262 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3266 /* Checks if DECL shadows a template parameter.
3268 [temp.local]: A template-parameter shall not be redeclared within its
3269 scope (including nested scopes).
3271 Emits an error and returns TRUE if the DECL shadows a parameter,
3272 returns FALSE otherwise. */
3275 check_template_shadow (tree decl)
3279 /* If we're not in a template, we can't possibly shadow a template
3281 if (!current_template_parms)
3284 /* Figure out what we're shadowing. */
3285 if (TREE_CODE (decl) == OVERLOAD)
3286 decl = OVL_CURRENT (decl);
3287 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3289 /* If there's no previous binding for this name, we're not shadowing
3290 anything, let alone a template parameter. */
3294 /* If we're not shadowing a template parameter, we're done. Note
3295 that OLDDECL might be an OVERLOAD (or perhaps even an
3296 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3298 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3301 /* We check for decl != olddecl to avoid bogus errors for using a
3302 name inside a class. We check TPFI to avoid duplicate errors for
3303 inline member templates. */
3305 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3308 error ("declaration of %q+#D", decl);
3309 error (" shadows template parm %q+#D", olddecl);
3313 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3314 ORIG_LEVEL, DECL, and TYPE. */
3317 build_template_parm_index (int index,
3323 tree t = make_node (TEMPLATE_PARM_INDEX);
3324 TEMPLATE_PARM_IDX (t) = index;
3325 TEMPLATE_PARM_LEVEL (t) = level;
3326 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3327 TEMPLATE_PARM_DECL (t) = decl;
3328 TREE_TYPE (t) = type;
3329 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3330 TREE_READONLY (t) = TREE_READONLY (decl);
3335 /* Find the canonical type parameter for the given template type
3336 parameter. Returns the canonical type parameter, which may be TYPE
3337 if no such parameter existed. */
3339 canonical_type_parameter (tree type)
3342 int idx = TEMPLATE_TYPE_IDX (type);
3343 if (!canonical_template_parms)
3344 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3346 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3347 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3349 list = VEC_index (tree, canonical_template_parms, idx);
3350 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3351 list = TREE_CHAIN (list);
3354 return TREE_VALUE (list);
3357 VEC_replace(tree, canonical_template_parms, idx,
3358 tree_cons (NULL_TREE, type,
3359 VEC_index (tree, canonical_template_parms, idx)));
3364 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3365 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3366 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3367 new one is created. */
3370 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3371 tsubst_flags_t complain)
3373 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3374 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3375 != TEMPLATE_PARM_LEVEL (index) - levels)
3376 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3378 tree orig_decl = TEMPLATE_PARM_DECL (index);
3381 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3382 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3383 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3384 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3385 DECL_ARTIFICIAL (decl) = 1;
3386 SET_DECL_TEMPLATE_PARM_P (decl);
3388 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3389 TEMPLATE_PARM_LEVEL (index) - levels,
3390 TEMPLATE_PARM_ORIG_LEVEL (index),
3392 TEMPLATE_PARM_DESCENDANTS (index) = t;
3393 TEMPLATE_PARM_PARAMETER_PACK (t)
3394 = TEMPLATE_PARM_PARAMETER_PACK (index);
3396 /* Template template parameters need this. */
3397 if (TREE_CODE (decl) == TEMPLATE_DECL)
3398 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3399 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3403 return TEMPLATE_PARM_DESCENDANTS (index);
3406 /* Process information from new template parameter PARM and append it to the
3407 LIST being built. This new parameter is a non-type parameter iff
3408 IS_NON_TYPE is true. This new parameter is a parameter
3409 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3413 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3414 bool is_parameter_pack)
3421 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3422 defval = TREE_PURPOSE (parm);
3426 tree p = tree_last (list);
3428 if (p && TREE_VALUE (p) != error_mark_node)
3431 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3432 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3434 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3444 parm = TREE_VALUE (parm);
3446 SET_DECL_TEMPLATE_PARM_P (parm);
3448 if (TREE_TYPE (parm) == error_mark_node)
3450 err_parm_list = build_tree_list (defval, parm);
3451 TREE_VALUE (err_parm_list) = error_mark_node;
3452 return chainon (list, err_parm_list);
3458 The top-level cv-qualifiers on the template-parameter are
3459 ignored when determining its type. */
3460 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3461 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3463 err_parm_list = build_tree_list (defval, parm);
3464 TREE_VALUE (err_parm_list) = error_mark_node;
3465 return chainon (list, err_parm_list);
3468 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3470 /* This template parameter is not a parameter pack, but it
3471 should be. Complain about "bare" parameter packs. */
3472 check_for_bare_parameter_packs (TREE_TYPE (parm));
3474 /* Recover by calling this a parameter pack. */
3475 is_parameter_pack = true;
3479 /* A template parameter is not modifiable. */
3480 TREE_CONSTANT (parm) = 1;
3481 TREE_READONLY (parm) = 1;
3482 decl = build_decl (parm_loc,
3483 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3484 TREE_CONSTANT (decl) = 1;
3485 TREE_READONLY (decl) = 1;
3486 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3487 = build_template_parm_index (idx, processing_template_decl,
3488 processing_template_decl,
3489 decl, TREE_TYPE (parm));
3491 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3492 = is_parameter_pack;
3497 parm = TREE_VALUE (TREE_VALUE (parm));
3499 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3501 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3502 /* This is for distinguishing between real templates and template
3503 template parameters */
3504 TREE_TYPE (parm) = t;
3505 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3510 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3511 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3512 decl = build_decl (parm_loc,
3513 TYPE_DECL, parm, t);
3516 TYPE_NAME (t) = decl;
3517 TYPE_STUB_DECL (t) = decl;
3519 TEMPLATE_TYPE_PARM_INDEX (t)
3520 = build_template_parm_index (idx, processing_template_decl,
3521 processing_template_decl,
3522 decl, TREE_TYPE (parm));
3523 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3524 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3526 DECL_ARTIFICIAL (decl) = 1;
3527 SET_DECL_TEMPLATE_PARM_P (decl);
3529 parm = build_tree_list (defval, parm);
3530 return chainon (list, parm);
3533 /* The end of a template parameter list has been reached. Process the
3534 tree list into a parameter vector, converting each parameter into a more
3535 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3539 end_template_parm_list (tree parms)
3543 tree saved_parmlist = make_tree_vec (list_length (parms));
3545 current_template_parms
3546 = tree_cons (size_int (processing_template_decl),
3547 saved_parmlist, current_template_parms);
3549 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3551 next = TREE_CHAIN (parm);
3552 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3553 TREE_CHAIN (parm) = NULL_TREE;
3556 --processing_template_parmlist;
3558 return saved_parmlist;
3561 /* end_template_decl is called after a template declaration is seen. */
3564 end_template_decl (void)
3566 reset_specialization ();
3568 if (! processing_template_decl)
3571 /* This matches the pushlevel in begin_template_parm_list. */
3574 --processing_template_decl;
3575 current_template_parms = TREE_CHAIN (current_template_parms);
3578 /* Within the declaration of a template, return all levels of template
3579 parameters that apply. The template parameters are represented as
3580 a TREE_VEC, in the form documented in cp-tree.h for template
3584 current_template_args (void)
3587 tree args = NULL_TREE;
3588 int length = TMPL_PARMS_DEPTH (current_template_parms);
3591 /* If there is only one level of template parameters, we do not
3592 create a TREE_VEC of TREE_VECs. Instead, we return a single
3593 TREE_VEC containing the arguments. */
3595 args = make_tree_vec (length);
3597 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3599 tree a = copy_node (TREE_VALUE (header));
3602 TREE_TYPE (a) = NULL_TREE;
3603 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3605 tree t = TREE_VEC_ELT (a, i);
3607 /* T will be a list if we are called from within a
3608 begin/end_template_parm_list pair, but a vector directly
3609 if within a begin/end_member_template_processing pair. */
3610 if (TREE_CODE (t) == TREE_LIST)
3614 if (!error_operand_p (t))
3616 if (TREE_CODE (t) == TYPE_DECL
3617 || TREE_CODE (t) == TEMPLATE_DECL)
3621 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3623 /* Turn this argument into a TYPE_ARGUMENT_PACK
3624 with a single element, which expands T. */
3625 tree vec = make_tree_vec (1);
3626 #ifdef ENABLE_CHECKING
3627 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3628 (vec, TREE_VEC_LENGTH (vec));
3630 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3632 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3633 SET_ARGUMENT_PACK_ARGS (t, vec);
3638 t = DECL_INITIAL (t);
3640 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3642 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3643 with a single element, which expands T. */
3644 tree vec = make_tree_vec (1);
3645 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3646 #ifdef ENABLE_CHECKING
3647 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3648 (vec, TREE_VEC_LENGTH (vec));
3650 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3652 t = make_node (NONTYPE_ARGUMENT_PACK);
3653 SET_ARGUMENT_PACK_ARGS (t, vec);
3654 TREE_TYPE (t) = type;
3657 TREE_VEC_ELT (a, i) = t;
3662 #ifdef ENABLE_CHECKING
3663 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
3667 TREE_VEC_ELT (args, --l) = a;
3675 /* Update the declared TYPE by doing any lookups which were thought to be
3676 dependent, but are not now that we know the SCOPE of the declarator. */
3679 maybe_update_decl_type (tree orig_type, tree scope)
3681 tree type = orig_type;
3683 if (type == NULL_TREE)
3686 if (TREE_CODE (orig_type) == TYPE_DECL)
3687 type = TREE_TYPE (type);
3689 if (scope && TYPE_P (scope) && dependent_type_p (scope)
3690 && dependent_type_p (type)
3691 /* Don't bother building up the args in this case. */
3692 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
3694 /* tsubst in the args corresponding to the template parameters,
3695 including auto if present. Most things will be unchanged, but
3696 make_typename_type and tsubst_qualified_id will resolve
3697 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
3698 tree args = current_template_args ();
3699 tree auto_node = type_uses_auto (type);
3702 tree auto_vec = make_tree_vec (1);
3703 TREE_VEC_ELT (auto_vec, 0) = auto_node;
3704 args = add_to_template_args (args, auto_vec);
3707 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
3711 if (type == error_mark_node)
3714 if (TREE_CODE (orig_type) == TYPE_DECL)
3716 if (same_type_p (type, TREE_TYPE (orig_type)))
3719 type = TYPE_NAME (type);
3724 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3725 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3726 a member template. Used by push_template_decl below. */
3729 build_template_decl (tree decl, tree parms, bool member_template_p)
3731 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3732 DECL_TEMPLATE_PARMS (tmpl) = parms;
3733 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3734 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3739 struct template_parm_data
3741 /* The level of the template parameters we are currently
3745 /* The index of the specialization argument we are currently
3749 /* An array whose size is the number of template parameters. The
3750 elements are nonzero if the parameter has been used in any one
3751 of the arguments processed so far. */
3754 /* An array whose size is the number of template arguments. The
3755 elements are nonzero if the argument makes use of template
3756 parameters of this level. */
3757 int* arg_uses_template_parms;
3760 /* Subroutine of push_template_decl used to see if each template
3761 parameter in a partial specialization is used in the explicit
3762 argument list. If T is of the LEVEL given in DATA (which is
3763 treated as a template_parm_data*), then DATA->PARMS is marked
3767 mark_template_parm (tree t, void* data)
3771 struct template_parm_data* tpd = (struct template_parm_data*) data;
3773 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3775 level = TEMPLATE_PARM_LEVEL (t);
3776 idx = TEMPLATE_PARM_IDX (t);
3780 level = TEMPLATE_TYPE_LEVEL (t);
3781 idx = TEMPLATE_TYPE_IDX (t);
3784 if (level == tpd->level)
3786 tpd->parms[idx] = 1;
3787 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3790 /* Return zero so that for_each_template_parm will continue the
3791 traversal of the tree; we want to mark *every* template parm. */
3795 /* Process the partial specialization DECL. */
3798 process_partial_specialization (tree decl)
3800 tree type = TREE_TYPE (decl);
3801 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3802 tree specargs = CLASSTYPE_TI_ARGS (type);
3803 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3804 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3806 int nargs = TREE_VEC_LENGTH (inner_args);
3809 int did_error_intro = 0;
3810 struct template_parm_data tpd;
3811 struct template_parm_data tpd2;
3813 gcc_assert (current_template_parms);
3815 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3816 ntparms = TREE_VEC_LENGTH (inner_parms);
3818 /* We check that each of the template parameters given in the
3819 partial specialization is used in the argument list to the
3820 specialization. For example:
3822 template <class T> struct S;
3823 template <class T> struct S<T*>;
3825 The second declaration is OK because `T*' uses the template
3826 parameter T, whereas
3828 template <class T> struct S<int>;
3830 is no good. Even trickier is:
3841 The S2<T> declaration is actually invalid; it is a
3842 full-specialization. Of course,
3845 struct S2<T (*)(U)>;
3847 or some such would have been OK. */
3848 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3849 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3850 memset (tpd.parms, 0, sizeof (int) * ntparms);
3852 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3853 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3854 for (i = 0; i < nargs; ++i)
3856 tpd.current_arg = i;
3857 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3858 &mark_template_parm,
3861 /*include_nondeduced_p=*/false);
3863 for (i = 0; i < ntparms; ++i)
3864 if (tpd.parms[i] == 0)
3866 /* One of the template parms was not used in the
3868 if (!did_error_intro)
3870 error ("template parameters not used in partial specialization:");
3871 did_error_intro = 1;
3874 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3877 /* [temp.class.spec]
3879 The argument list of the specialization shall not be identical to
3880 the implicit argument list of the primary template. */
3881 if (comp_template_args
3883 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3885 error ("partial specialization %qT does not specialize any template arguments", type);
3887 /* [temp.class.spec]
3889 A partially specialized non-type argument expression shall not
3890 involve template parameters of the partial specialization except
3891 when the argument expression is a simple identifier.
3893 The type of a template parameter corresponding to a specialized
3894 non-type argument shall not be dependent on a parameter of the
3897 Also, we verify that pack expansions only occur at the
3898 end of the argument list. */
3899 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3901 for (i = 0; i < nargs; ++i)
3903 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3904 tree arg = TREE_VEC_ELT (inner_args, i);
3905 tree packed_args = NULL_TREE;
3908 if (ARGUMENT_PACK_P (arg))
3910 /* Extract the arguments from the argument pack. We'll be
3911 iterating over these in the following loop. */
3912 packed_args = ARGUMENT_PACK_ARGS (arg);
3913 len = TREE_VEC_LENGTH (packed_args);
3916 for (j = 0; j < len; j++)
3919 /* Get the Jth argument in the parameter pack. */
3920 arg = TREE_VEC_ELT (packed_args, j);
3922 if (PACK_EXPANSION_P (arg))
3924 /* Pack expansions must come at the end of the
3926 if ((packed_args && j < len - 1)
3927 || (!packed_args && i < nargs - 1))
3929 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3930 error ("parameter pack argument %qE must be at the "
3931 "end of the template argument list", arg);
3933 error ("parameter pack argument %qT must be at the "
3934 "end of the template argument list", arg);
3938 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3939 /* We only care about the pattern. */
3940 arg = PACK_EXPANSION_PATTERN (arg);
3942 if (/* These first two lines are the `non-type' bit. */
3944 && TREE_CODE (arg) != TEMPLATE_DECL
3945 /* This next line is the `argument expression is not just a
3946 simple identifier' condition and also the `specialized
3947 non-type argument' bit. */
3948 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3950 if ((!packed_args && tpd.arg_uses_template_parms[i])
3951 || (packed_args && uses_template_parms (arg)))
3952 error ("template argument %qE involves template parameter(s)",
3956 /* Look at the corresponding template parameter,
3957 marking which template parameters its type depends
3959 tree type = TREE_TYPE (parm);
3963 /* We haven't yet initialized TPD2. Do so now. */
3964 tpd2.arg_uses_template_parms
3965 = (int *) alloca (sizeof (int) * nargs);
3966 /* The number of parameters here is the number in the
3967 main template, which, as checked in the assertion
3969 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3971 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3974 /* Mark the template parameters. But this time, we're
3975 looking for the template parameters of the main
3976 template, not in the specialization. */
3977 tpd2.current_arg = i;
3978 tpd2.arg_uses_template_parms[i] = 0;
3979 memset (tpd2.parms, 0, sizeof (int) * nargs);
3980 for_each_template_parm (type,
3981 &mark_template_parm,
3984 /*include_nondeduced_p=*/false);
3986 if (tpd2.arg_uses_template_parms [i])
3988 /* The type depended on some template parameters.
3989 If they are fully specialized in the
3990 specialization, that's OK. */
3992 for (j = 0; j < nargs; ++j)
3993 if (tpd2.parms[j] != 0
3994 && tpd.arg_uses_template_parms [j])
3996 error ("type %qT of template argument %qE depends "
3997 "on template parameter(s)",
4008 /* We should only get here once. */
4009 gcc_assert (!COMPLETE_TYPE_P (type));
4011 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4012 = tree_cons (specargs, inner_parms,
4013 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4014 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4018 /* Check that a template declaration's use of default arguments and
4019 parameter packs is not invalid. Here, PARMS are the template
4020 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4021 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4025 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4026 declaration (but not a definition); 1 indicates a declaration, 2
4027 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4028 emitted for extraneous default arguments.
4030 Returns TRUE if there were no errors found, FALSE otherwise. */
4033 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4034 int is_partial, int is_friend_decl)
4037 int last_level_to_check;
4039 bool no_errors = true;
4043 A default template-argument shall not be specified in a
4044 function template declaration or a function template definition, nor
4045 in the template-parameter-list of the definition of a member of a
4048 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4049 /* You can't have a function template declaration in a local
4050 scope, nor you can you define a member of a class template in a
4054 if (current_class_type
4055 && !TYPE_BEING_DEFINED (current_class_type)
4056 && DECL_LANG_SPECIFIC (decl)
4057 && DECL_DECLARES_FUNCTION_P (decl)
4058 /* If this is either a friend defined in the scope of the class
4059 or a member function. */
4060 && (DECL_FUNCTION_MEMBER_P (decl)
4061 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4062 : DECL_FRIEND_CONTEXT (decl)
4063 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4065 /* And, if it was a member function, it really was defined in
4066 the scope of the class. */
4067 && (!DECL_FUNCTION_MEMBER_P (decl)
4068 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4069 /* We already checked these parameters when the template was
4070 declared, so there's no need to do it again now. This function
4071 was defined in class scope, but we're processing it's body now
4072 that the class is complete. */
4075 /* Core issue 226 (C++0x only): the following only applies to class
4077 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4081 If a template-parameter has a default template-argument, all
4082 subsequent template-parameters shall have a default
4083 template-argument supplied. */
4084 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4086 tree inner_parms = TREE_VALUE (parm_level);
4087 int ntparms = TREE_VEC_LENGTH (inner_parms);
4088 int seen_def_arg_p = 0;
4091 for (i = 0; i < ntparms; ++i)
4093 tree parm = TREE_VEC_ELT (inner_parms, i);
4095 if (parm == error_mark_node)
4098 if (TREE_PURPOSE (parm))
4100 else if (seen_def_arg_p
4101 && !template_parameter_pack_p (TREE_VALUE (parm)))
4103 error ("no default argument for %qD", TREE_VALUE (parm));
4104 /* For better subsequent error-recovery, we indicate that
4105 there should have been a default argument. */
4106 TREE_PURPOSE (parm) = error_mark_node;
4112 /* Don't complain about an enclosing partial
4114 && parm_level == parms
4115 && TREE_CODE (decl) == TYPE_DECL
4117 && template_parameter_pack_p (TREE_VALUE (parm)))
4119 /* A primary class template can only have one
4120 parameter pack, at the end of the template
4123 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4124 error ("parameter pack %qE must be at the end of the"
4125 " template parameter list", TREE_VALUE (parm));
4127 error ("parameter pack %qT must be at the end of the"
4128 " template parameter list",
4129 TREE_TYPE (TREE_VALUE (parm)));
4131 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4139 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4143 /* For an ordinary class template, default template arguments are
4144 allowed at the innermost level, e.g.:
4145 template <class T = int>
4147 but, in a partial specialization, they're not allowed even
4148 there, as we have in [temp.class.spec]:
4150 The template parameter list of a specialization shall not
4151 contain default template argument values.
4153 So, for a partial specialization, or for a function template
4154 (in C++98/C++03), we look at all of them. */
4157 /* But, for a primary class template that is not a partial
4158 specialization we look at all template parameters except the
4160 parms = TREE_CHAIN (parms);
4162 /* Figure out what error message to issue. */
4163 if (is_friend_decl == 2)
4164 msg = G_("default template arguments may not be used in function template "
4165 "friend re-declaration");
4166 else if (is_friend_decl)
4167 msg = G_("default template arguments may not be used in function template "
4168 "friend declarations");
4169 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4170 msg = G_("default template arguments may not be used in function templates "
4171 "without -std=c++0x or -std=gnu++0x");
4172 else if (is_partial)
4173 msg = G_("default template arguments may not be used in "
4174 "partial specializations");
4176 msg = G_("default argument for template parameter for class enclosing %qD");
4178 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4179 /* If we're inside a class definition, there's no need to
4180 examine the parameters to the class itself. On the one
4181 hand, they will be checked when the class is defined, and,
4182 on the other, default arguments are valid in things like:
4183 template <class T = double>
4184 struct S { template <class U> void f(U); };
4185 Here the default argument for `S' has no bearing on the
4186 declaration of `f'. */
4187 last_level_to_check = template_class_depth (current_class_type) + 1;
4189 /* Check everything. */
4190 last_level_to_check = 0;
4192 for (parm_level = parms;
4193 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4194 parm_level = TREE_CHAIN (parm_level))
4196 tree inner_parms = TREE_VALUE (parm_level);
4200 ntparms = TREE_VEC_LENGTH (inner_parms);
4201 for (i = 0; i < ntparms; ++i)
4203 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4206 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4211 if (is_friend_decl == 2)
4218 /* Clear out the default argument so that we are not
4220 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4224 /* At this point, if we're still interested in issuing messages,
4225 they must apply to classes surrounding the object declared. */
4227 msg = G_("default argument for template parameter for class "
4234 /* Worker for push_template_decl_real, called via
4235 for_each_template_parm. DATA is really an int, indicating the
4236 level of the parameters we are interested in. If T is a template
4237 parameter of that level, return nonzero. */
4240 template_parm_this_level_p (tree t, void* data)
4242 int this_level = *(int *)data;
4245 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4246 level = TEMPLATE_PARM_LEVEL (t);
4248 level = TEMPLATE_TYPE_LEVEL (t);
4249 return level == this_level;
4252 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4253 parameters given by current_template_args, or reuses a
4254 previously existing one, if appropriate. Returns the DECL, or an
4255 equivalent one, if it is replaced via a call to duplicate_decls.
4257 If IS_FRIEND is true, DECL is a friend declaration. */
4260 push_template_decl_real (tree decl, bool is_friend)
4268 int new_template_p = 0;
4269 /* True if the template is a member template, in the sense of
4271 bool member_template_p = false;
4273 if (decl == error_mark_node || !current_template_parms)
4274 return error_mark_node;
4276 /* See if this is a partial specialization. */
4277 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4278 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4279 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4281 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4285 /* For a friend, we want the context of the friend function, not
4286 the type of which it is a friend. */
4287 ctx = DECL_CONTEXT (decl);
4288 else if (CP_DECL_CONTEXT (decl)
4289 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4290 /* In the case of a virtual function, we want the class in which
4292 ctx = CP_DECL_CONTEXT (decl);
4294 /* Otherwise, if we're currently defining some class, the DECL
4295 is assumed to be a member of the class. */
4296 ctx = current_scope ();
4298 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4301 if (!DECL_CONTEXT (decl))
4302 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4304 /* See if this is a primary template. */
4305 if (is_friend && ctx)
4306 /* A friend template that specifies a class context, i.e.
4307 template <typename T> friend void A<T>::f();
4311 primary = template_parm_scope_p ();
4315 if (DECL_CLASS_SCOPE_P (decl))
4316 member_template_p = true;
4317 if (TREE_CODE (decl) == TYPE_DECL
4318 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4320 error ("template class without a name");
4321 return error_mark_node;
4323 else if (TREE_CODE (decl) == FUNCTION_DECL)
4325 if (DECL_DESTRUCTOR_P (decl))
4329 A destructor shall not be a member template. */
4330 error ("destructor %qD declared as member template", decl);
4331 return error_mark_node;
4333 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4334 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4335 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4336 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4337 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4338 == void_list_node)))
4340 /* [basic.stc.dynamic.allocation]
4342 An allocation function can be a function
4343 template. ... Template allocation functions shall
4344 have two or more parameters. */
4345 error ("invalid template declaration of %qD", decl);
4346 return error_mark_node;
4349 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4350 && CLASS_TYPE_P (TREE_TYPE (decl)))
4354 error ("template declaration of %q#D", decl);
4355 return error_mark_node;
4359 /* Check to see that the rules regarding the use of default
4360 arguments are not being violated. */
4361 check_default_tmpl_args (decl, current_template_parms,
4362 primary, is_partial, /*is_friend_decl=*/0);
4364 /* Ensure that there are no parameter packs in the type of this
4365 declaration that have not been expanded. */
4366 if (TREE_CODE (decl) == FUNCTION_DECL)
4368 /* Check each of the arguments individually to see if there are
4369 any bare parameter packs. */
4370 tree type = TREE_TYPE (decl);
4371 tree arg = DECL_ARGUMENTS (decl);
4372 tree argtype = TYPE_ARG_TYPES (type);
4374 while (arg && argtype)
4376 if (!FUNCTION_PARAMETER_PACK_P (arg)
4377 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4379 /* This is a PARM_DECL that contains unexpanded parameter
4380 packs. We have already complained about this in the
4381 check_for_bare_parameter_packs call, so just replace
4382 these types with ERROR_MARK_NODE. */
4383 TREE_TYPE (arg) = error_mark_node;
4384 TREE_VALUE (argtype) = error_mark_node;
4387 arg = TREE_CHAIN (arg);
4388 argtype = TREE_CHAIN (argtype);
4391 /* Check for bare parameter packs in the return type and the
4392 exception specifiers. */
4393 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4394 /* Errors were already issued, set return type to int
4395 as the frontend doesn't expect error_mark_node as
4397 TREE_TYPE (type) = integer_type_node;
4398 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4399 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4401 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4403 TREE_TYPE (decl) = error_mark_node;
4404 return error_mark_node;
4408 return process_partial_specialization (decl);
4410 args = current_template_args ();
4413 || TREE_CODE (ctx) == FUNCTION_DECL
4414 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4415 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4417 if (DECL_LANG_SPECIFIC (decl)
4418 && DECL_TEMPLATE_INFO (decl)
4419 && DECL_TI_TEMPLATE (decl))
4420 tmpl = DECL_TI_TEMPLATE (decl);
4421 /* If DECL is a TYPE_DECL for a class-template, then there won't
4422 be DECL_LANG_SPECIFIC. The information equivalent to
4423 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4424 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4425 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4426 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4428 /* Since a template declaration already existed for this
4429 class-type, we must be redeclaring it here. Make sure
4430 that the redeclaration is valid. */
4431 redeclare_class_template (TREE_TYPE (decl),
4432 current_template_parms);
4433 /* We don't need to create a new TEMPLATE_DECL; just use the
4434 one we already had. */
4435 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4439 tmpl = build_template_decl (decl, current_template_parms,
4443 if (DECL_LANG_SPECIFIC (decl)
4444 && DECL_TEMPLATE_SPECIALIZATION (decl))
4446 /* A specialization of a member template of a template
4448 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4449 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4450 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4456 tree a, t, current, parms;
4458 tree tinfo = get_template_info (decl);
4462 error ("template definition of non-template %q#D", decl);
4463 return error_mark_node;
4466 tmpl = TI_TEMPLATE (tinfo);
4468 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4469 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4470 && DECL_TEMPLATE_SPECIALIZATION (decl)
4471 && DECL_MEMBER_TEMPLATE_P (tmpl))
4475 /* The declaration is a specialization of a member
4476 template, declared outside the class. Therefore, the
4477 innermost template arguments will be NULL, so we
4478 replace them with the arguments determined by the
4479 earlier call to check_explicit_specialization. */
4480 args = DECL_TI_ARGS (decl);
4483 = build_template_decl (decl, current_template_parms,
4485 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4486 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4487 DECL_TI_TEMPLATE (decl) = new_tmpl;
4488 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4489 DECL_TEMPLATE_INFO (new_tmpl)
4490 = build_template_info (tmpl, args);
4492 register_specialization (new_tmpl,
4493 most_general_template (tmpl),
4499 /* Make sure the template headers we got make sense. */
4501 parms = DECL_TEMPLATE_PARMS (tmpl);
4502 i = TMPL_PARMS_DEPTH (parms);
4503 if (TMPL_ARGS_DEPTH (args) != i)
4505 error ("expected %d levels of template parms for %q#D, got %d",
4506 i, decl, TMPL_ARGS_DEPTH (args));
4509 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4511 a = TMPL_ARGS_LEVEL (args, i);
4512 t = INNERMOST_TEMPLATE_PARMS (parms);
4514 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4516 if (current == decl)
4517 error ("got %d template parameters for %q#D",
4518 TREE_VEC_LENGTH (a), decl);
4520 error ("got %d template parameters for %q#T",
4521 TREE_VEC_LENGTH (a), current);
4522 error (" but %d required", TREE_VEC_LENGTH (t));
4523 return error_mark_node;
4526 if (current == decl)
4529 current = (TYPE_P (current)
4530 ? TYPE_CONTEXT (current)
4531 : DECL_CONTEXT (current));
4534 /* Check that the parms are used in the appropriate qualifying scopes
4535 in the declarator. */
4536 if (!comp_template_args
4538 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4541 template arguments to %qD do not match original template %qD",
4542 decl, DECL_TEMPLATE_RESULT (tmpl));
4543 if (!uses_template_parms (TI_ARGS (tinfo)))
4544 inform (input_location, "use template<> for an explicit specialization");
4545 /* Avoid crash in import_export_decl. */
4546 DECL_INTERFACE_KNOWN (decl) = 1;
4547 return error_mark_node;
4551 DECL_TEMPLATE_RESULT (tmpl) = decl;
4552 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4554 /* Push template declarations for global functions and types. Note
4555 that we do not try to push a global template friend declared in a
4556 template class; such a thing may well depend on the template
4557 parameters of the class. */
4558 if (new_template_p && !ctx
4559 && !(is_friend && template_class_depth (current_class_type) > 0))
4561 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4562 if (tmpl == error_mark_node)
4563 return error_mark_node;
4565 /* Hide template friend classes that haven't been declared yet. */
4566 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4568 DECL_ANTICIPATED (tmpl) = 1;
4569 DECL_FRIEND_P (tmpl) = 1;
4575 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4578 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4579 if (DECL_CONV_FN_P (tmpl))
4581 int depth = TMPL_PARMS_DEPTH (parms);
4583 /* It is a conversion operator. See if the type converted to
4584 depends on innermost template operands. */
4586 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4588 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4591 /* Give template template parms a DECL_CONTEXT of the template
4592 for which they are a parameter. */
4593 parms = INNERMOST_TEMPLATE_PARMS (parms);
4594 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4596 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4597 if (TREE_CODE (parm) == TEMPLATE_DECL)
4598 DECL_CONTEXT (parm) = tmpl;
4600 if (TREE_CODE (TREE_TYPE (parm)) == TEMPLATE_TYPE_PARM)
4601 DECL_CONTEXT (TYPE_NAME (TREE_TYPE (parm))) = tmpl;
4605 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4606 back to its most general template. If TMPL is a specialization,
4607 ARGS may only have the innermost set of arguments. Add the missing
4608 argument levels if necessary. */
4609 if (DECL_TEMPLATE_INFO (tmpl))
4610 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4612 info = build_template_info (tmpl, args);
4614 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4615 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4616 else if (DECL_LANG_SPECIFIC (decl))
4617 DECL_TEMPLATE_INFO (decl) = info;
4619 return DECL_TEMPLATE_RESULT (tmpl);
4623 push_template_decl (tree decl)
4625 return push_template_decl_real (decl, false);
4628 /* Called when a class template TYPE is redeclared with the indicated
4629 template PARMS, e.g.:
4631 template <class T> struct S;
4632 template <class T> struct S {}; */
4635 redeclare_class_template (tree type, tree parms)
4641 if (!TYPE_TEMPLATE_INFO (type))
4643 error ("%qT is not a template type", type);
4647 tmpl = TYPE_TI_TEMPLATE (type);
4648 if (!PRIMARY_TEMPLATE_P (tmpl))
4649 /* The type is nested in some template class. Nothing to worry
4650 about here; there are no new template parameters for the nested
4656 error ("template specifiers not specified in declaration of %qD",
4661 parms = INNERMOST_TEMPLATE_PARMS (parms);
4662 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4664 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4666 error ("redeclared with %d template parameter(s)",
4667 TREE_VEC_LENGTH (parms));
4668 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4669 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4673 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4680 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4681 || TREE_VEC_ELT (parms, i) == error_mark_node)
4684 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4685 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4686 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4687 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4689 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4691 if (tmpl_parm != error_mark_node
4692 && (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_partial_instantiation;
6384 gen_tmpl = most_general_template (templ);
6385 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6386 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6387 arg_depth = TMPL_ARGS_DEPTH (arglist);
6389 if (arg_depth == 1 && parm_depth > 1)
6391 /* We've been given an incomplete set of template arguments.
6394 template <class T> struct S1 {
6395 template <class U> struct S2 {};
6396 template <class U> struct S2<U*> {};
6399 we will be called with an ARGLIST of `U*', but the
6400 TEMPLATE will be `template <class T> template
6401 <class U> struct S1<T>::S2'. We must fill in the missing
6404 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6406 arg_depth = TMPL_ARGS_DEPTH (arglist);
6409 /* Now we should have enough arguments. */
6410 gcc_assert (parm_depth == arg_depth);
6412 /* From here on, we're only interested in the most general
6415 /* Calculate the BOUND_ARGS. These will be the args that are
6416 actually tsubst'd into the definition to create the
6420 /* We have multiple levels of arguments to coerce, at once. */
6422 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6424 tree bound_args = make_tree_vec (parm_depth);
6426 for (i = saved_depth,
6427 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6428 i > 0 && t != NULL_TREE;
6429 --i, t = TREE_CHAIN (t))
6431 tree a = coerce_template_parms (TREE_VALUE (t),
6434 /*require_all_args=*/true,
6435 /*use_default_args=*/true);
6437 /* Don't process further if one of the levels fails. */
6438 if (a == error_mark_node)
6440 /* Restore the ARGLIST to its full size. */
6441 TREE_VEC_LENGTH (arglist) = saved_depth;
6442 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6445 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6447 /* We temporarily reduce the length of the ARGLIST so
6448 that coerce_template_parms will see only the arguments
6449 corresponding to the template parameters it is
6451 TREE_VEC_LENGTH (arglist)--;
6454 /* Restore the ARGLIST to its full size. */
6455 TREE_VEC_LENGTH (arglist) = saved_depth;
6457 arglist = bound_args;
6461 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6462 INNERMOST_TEMPLATE_ARGS (arglist),
6465 /*require_all_args=*/true,
6466 /*use_default_args=*/true);
6468 if (arglist == error_mark_node)
6469 /* We were unable to bind the arguments. */
6470 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6472 /* In the scope of a template class, explicit references to the
6473 template class refer to the type of the template, not any
6474 instantiation of it. For example, in:
6476 template <class T> class C { void f(C<T>); }
6478 the `C<T>' is just the same as `C'. Outside of the
6479 class, however, such a reference is an instantiation. */
6481 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6482 || currently_open_class (template_type))
6483 /* comp_template_args is expensive, check it last. */
6484 && comp_template_args (TYPE_TI_ARGS (template_type),
6486 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6488 /* If we already have this specialization, return it. */
6489 elt.tmpl = gen_tmpl;
6491 hash = hash_specialization (&elt);
6492 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6496 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6498 /* This type is a "partial instantiation" if any of the template
6499 arguments still involve template parameters. Note that we set
6500 IS_PARTIAL_INSTANTIATION for partial specializations as
6502 is_partial_instantiation = uses_template_parms (arglist);
6504 /* If the deduced arguments are invalid, then the binding
6506 if (!is_partial_instantiation
6507 && check_instantiated_args (gen_tmpl,
6508 INNERMOST_TEMPLATE_ARGS (arglist),
6510 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6512 if (!is_partial_instantiation
6513 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6514 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6515 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6517 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6518 DECL_NAME (gen_tmpl),
6519 /*tag_scope=*/ts_global);
6520 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6523 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6526 context = global_namespace;
6528 /* Create the type. */
6529 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6531 if (!is_partial_instantiation)
6533 set_current_access_from_decl (TYPE_NAME (template_type));
6534 t = start_enum (TYPE_IDENTIFIER (template_type),
6535 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6536 arglist, complain, in_decl),
6537 SCOPED_ENUM_P (template_type));
6541 /* We don't want to call start_enum for this type, since
6542 the values for the enumeration constants may involve
6543 template parameters. And, no one should be interested
6544 in the enumeration constants for such a type. */
6545 t = cxx_make_type (ENUMERAL_TYPE);
6546 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6551 t = make_class_type (TREE_CODE (template_type));
6552 CLASSTYPE_DECLARED_CLASS (t)
6553 = CLASSTYPE_DECLARED_CLASS (template_type);
6554 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6555 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6557 /* A local class. Make sure the decl gets registered properly. */
6558 if (context == current_function_decl)
6559 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6561 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6562 /* This instantiation is another name for the primary
6563 template type. Set the TYPE_CANONICAL field
6565 TYPE_CANONICAL (t) = template_type;
6566 else if (any_template_arguments_need_structural_equality_p (arglist))
6567 /* Some of the template arguments require structural
6568 equality testing, so this template class requires
6569 structural equality testing. */
6570 SET_TYPE_STRUCTURAL_EQUALITY (t);
6573 /* If we called start_enum or pushtag above, this information
6574 will already be set up. */
6577 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6579 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6580 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6581 DECL_SOURCE_LOCATION (type_decl)
6582 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6585 type_decl = TYPE_NAME (t);
6587 TREE_PRIVATE (type_decl)
6588 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6589 TREE_PROTECTED (type_decl)
6590 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6591 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6593 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6594 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6597 /* Set up the template information. We have to figure out which
6598 template is the immediate parent if this is a full
6600 if (parm_depth == 1 || is_partial_instantiation
6601 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6602 /* This case is easy; there are no member templates involved. */
6606 /* This is a full instantiation of a member template. Find
6607 the partial instantiation of which this is an instance. */
6609 /* Temporarily reduce by one the number of levels in the ARGLIST
6610 so as to avoid comparing the last set of arguments. */
6611 TREE_VEC_LENGTH (arglist)--;
6612 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6613 TREE_VEC_LENGTH (arglist)++;
6614 found = CLASSTYPE_TI_TEMPLATE (found);
6617 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
6620 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6621 &elt, hash, INSERT);
6622 *slot = GGC_NEW (spec_entry);
6625 /* Note this use of the partial instantiation so we can check it
6626 later in maybe_process_partial_specialization. */
6627 DECL_TEMPLATE_INSTANTIATIONS (templ)
6628 = tree_cons (arglist, t,
6629 DECL_TEMPLATE_INSTANTIATIONS (templ));
6631 if (TREE_CODE (t) == ENUMERAL_TYPE
6632 && !is_partial_instantiation)
6633 /* Now that the type has been registered on the instantiations
6634 list, we set up the enumerators. Because the enumeration
6635 constants may involve the enumeration type itself, we make
6636 sure to register the type first, and then create the
6637 constants. That way, doing tsubst_expr for the enumeration
6638 constants won't result in recursive calls here; we'll find
6639 the instantiation and exit above. */
6640 tsubst_enum (template_type, t, arglist);
6642 if (is_partial_instantiation)
6643 /* If the type makes use of template parameters, the
6644 code that generates debugging information will crash. */
6645 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6647 /* Possibly limit visibility based on template args. */
6648 TREE_PUBLIC (type_decl) = 1;
6649 determine_visibility (type_decl);
6651 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6653 timevar_pop (TV_NAME_LOOKUP);
6660 /* True when we should also visit template parameters that occur in
6661 non-deduced contexts. */
6662 bool include_nondeduced_p;
6663 struct pointer_set_t *visited;
6666 /* Called from for_each_template_parm via walk_tree. */
6669 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6672 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6673 tree_fn_t fn = pfd->fn;
6674 void *data = pfd->data;
6677 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6678 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6679 pfd->include_nondeduced_p))
6680 return error_mark_node;
6682 switch (TREE_CODE (t))
6685 if (TYPE_PTRMEMFUNC_P (t))
6691 if (!TYPE_TEMPLATE_INFO (t))
6693 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
6694 fn, data, pfd->visited,
6695 pfd->include_nondeduced_p))
6696 return error_mark_node;
6700 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6701 fn, data, pfd->visited,
6702 pfd->include_nondeduced_p)
6703 || for_each_template_parm (TYPE_MAX_VALUE (t),
6704 fn, data, pfd->visited,
6705 pfd->include_nondeduced_p))
6706 return error_mark_node;
6710 /* Since we're not going to walk subtrees, we have to do this
6712 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6713 pfd->visited, pfd->include_nondeduced_p))
6714 return error_mark_node;
6718 /* Check the return type. */
6719 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6720 pfd->include_nondeduced_p))
6721 return error_mark_node;
6723 /* Check the parameter types. Since default arguments are not
6724 instantiated until they are needed, the TYPE_ARG_TYPES may
6725 contain expressions that involve template parameters. But,
6726 no-one should be looking at them yet. And, once they're
6727 instantiated, they don't contain template parameters, so
6728 there's no point in looking at them then, either. */
6732 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6733 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6734 pfd->visited, pfd->include_nondeduced_p))
6735 return error_mark_node;
6737 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6738 want walk_tree walking into them itself. */
6744 if (pfd->include_nondeduced_p
6745 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6747 pfd->include_nondeduced_p))
6748 return error_mark_node;
6753 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6754 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6755 pfd->visited, pfd->include_nondeduced_p))
6756 return error_mark_node;
6761 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6762 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6763 pfd->visited, pfd->include_nondeduced_p))
6764 return error_mark_node;
6765 if (DECL_CONTEXT (t)
6766 && pfd->include_nondeduced_p
6767 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6768 pfd->visited, pfd->include_nondeduced_p))
6769 return error_mark_node;
6772 case BOUND_TEMPLATE_TEMPLATE_PARM:
6773 /* Record template parameters such as `T' inside `TT<T>'. */
6774 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6775 pfd->include_nondeduced_p))
6776 return error_mark_node;
6779 case TEMPLATE_TEMPLATE_PARM:
6780 case TEMPLATE_TYPE_PARM:
6781 case TEMPLATE_PARM_INDEX:
6782 if (fn && (*fn)(t, data))
6783 return error_mark_node;
6785 return error_mark_node;
6789 /* A template template parameter is encountered. */
6790 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6791 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6792 pfd->include_nondeduced_p))
6793 return error_mark_node;
6795 /* Already substituted template template parameter */
6801 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6803 pfd->include_nondeduced_p))
6804 return error_mark_node;
6808 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6809 && pfd->include_nondeduced_p
6810 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6811 (TREE_TYPE (t)), fn, data,
6812 pfd->visited, pfd->include_nondeduced_p))
6813 return error_mark_node;
6818 /* If there's no type, then this thing must be some expression
6819 involving template parameters. */
6820 if (!fn && !TREE_TYPE (t))
6821 return error_mark_node;
6826 case REINTERPRET_CAST_EXPR:
6827 case CONST_CAST_EXPR:
6828 case STATIC_CAST_EXPR:
6829 case DYNAMIC_CAST_EXPR:
6833 case PSEUDO_DTOR_EXPR:
6835 return error_mark_node;
6842 /* We didn't find any template parameters we liked. */
6846 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6847 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6848 call FN with the parameter and the DATA.
6849 If FN returns nonzero, the iteration is terminated, and
6850 for_each_template_parm returns 1. Otherwise, the iteration
6851 continues. If FN never returns a nonzero value, the value
6852 returned by for_each_template_parm is 0. If FN is NULL, it is
6853 considered to be the function which always returns 1.
6855 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6856 parameters that occur in non-deduced contexts. When false, only
6857 visits those template parameters that can be deduced. */
6860 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6861 struct pointer_set_t *visited,
6862 bool include_nondeduced_p)
6864 struct pair_fn_data pfd;
6870 pfd.include_nondeduced_p = include_nondeduced_p;
6872 /* Walk the tree. (Conceptually, we would like to walk without
6873 duplicates, but for_each_template_parm_r recursively calls
6874 for_each_template_parm, so we would need to reorganize a fair
6875 bit to use walk_tree_without_duplicates, so we keep our own
6878 pfd.visited = visited;
6880 pfd.visited = pointer_set_create ();
6881 result = cp_walk_tree (&t,
6882 for_each_template_parm_r,
6884 pfd.visited) != NULL_TREE;
6889 pointer_set_destroy (pfd.visited);
6896 /* Returns true if T depends on any template parameter. */
6899 uses_template_parms (tree t)
6902 int saved_processing_template_decl;
6904 saved_processing_template_decl = processing_template_decl;
6905 if (!saved_processing_template_decl)
6906 processing_template_decl = 1;
6908 dependent_p = dependent_type_p (t);
6909 else if (TREE_CODE (t) == TREE_VEC)
6910 dependent_p = any_dependent_template_arguments_p (t);
6911 else if (TREE_CODE (t) == TREE_LIST)
6912 dependent_p = (uses_template_parms (TREE_VALUE (t))
6913 || uses_template_parms (TREE_CHAIN (t)));
6914 else if (TREE_CODE (t) == TYPE_DECL)
6915 dependent_p = dependent_type_p (TREE_TYPE (t));
6918 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6919 || TREE_CODE (t) == OVERLOAD
6920 || TREE_CODE (t) == BASELINK
6921 || TREE_CODE (t) == IDENTIFIER_NODE
6922 || TREE_CODE (t) == TRAIT_EXPR
6923 || TREE_CODE (t) == CONSTRUCTOR
6924 || CONSTANT_CLASS_P (t))
6925 dependent_p = (type_dependent_expression_p (t)
6926 || value_dependent_expression_p (t));
6929 gcc_assert (t == error_mark_node);
6930 dependent_p = false;
6933 processing_template_decl = saved_processing_template_decl;
6938 /* Returns true if T depends on any template parameter with level LEVEL. */
6941 uses_template_parms_level (tree t, int level)
6943 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6944 /*include_nondeduced_p=*/true);
6947 static int tinst_depth;
6948 extern int max_tinst_depth;
6949 #ifdef GATHER_STATISTICS
6952 static int tinst_level_tick;
6953 static int last_template_error_tick;
6955 /* We're starting to instantiate D; record the template instantiation context
6956 for diagnostics and to restore it later. */
6959 push_tinst_level (tree d)
6961 struct tinst_level *new_level;
6963 if (tinst_depth >= max_tinst_depth)
6965 /* If the instantiation in question still has unbound template parms,
6966 we don't really care if we can't instantiate it, so just return.
6967 This happens with base instantiation for implicit `typename'. */
6968 if (uses_template_parms (d))
6971 last_template_error_tick = tinst_level_tick;
6972 error ("template instantiation depth exceeds maximum of %d (use "
6973 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6974 max_tinst_depth, d);
6976 print_instantiation_context ();
6981 new_level = GGC_NEW (struct tinst_level);
6982 new_level->decl = d;
6983 new_level->locus = input_location;
6984 new_level->in_system_header_p = in_system_header;
6985 new_level->next = current_tinst_level;
6986 current_tinst_level = new_level;
6989 #ifdef GATHER_STATISTICS
6990 if (tinst_depth > depth_reached)
6991 depth_reached = tinst_depth;
6998 /* We're done instantiating this template; return to the instantiation
7002 pop_tinst_level (void)
7004 /* Restore the filename and line number stashed away when we started
7005 this instantiation. */
7006 input_location = current_tinst_level->locus;
7007 current_tinst_level = current_tinst_level->next;
7012 /* We're instantiating a deferred template; restore the template
7013 instantiation context in which the instantiation was requested, which
7014 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7017 reopen_tinst_level (struct tinst_level *level)
7019 struct tinst_level *t;
7022 for (t = level; t; t = t->next)
7025 current_tinst_level = level;
7030 /* Returns the TINST_LEVEL which gives the original instantiation
7033 struct tinst_level *
7034 outermost_tinst_level (void)
7036 struct tinst_level *level = current_tinst_level;
7039 level = level->next;
7043 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
7046 parameter_of_template_p (tree parm, tree templ)
7051 if (!parm || !templ)
7054 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
7055 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7057 parms = DECL_TEMPLATE_PARMS (templ);
7058 parms = INNERMOST_TEMPLATE_PARMS (parms);
7060 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
7061 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
7067 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
7068 vector of template arguments, as for tsubst.
7070 Returns an appropriate tsubst'd friend declaration. */
7073 tsubst_friend_function (tree decl, tree args)
7077 if (TREE_CODE (decl) == FUNCTION_DECL
7078 && DECL_TEMPLATE_INSTANTIATION (decl)
7079 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
7080 /* This was a friend declared with an explicit template
7081 argument list, e.g.:
7085 to indicate that f was a template instantiation, not a new
7086 function declaration. Now, we have to figure out what
7087 instantiation of what template. */
7089 tree template_id, arglist, fns;
7092 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
7094 /* Friend functions are looked up in the containing namespace scope.
7095 We must enter that scope, to avoid finding member functions of the
7096 current class with same name. */
7097 push_nested_namespace (ns);
7098 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
7099 tf_warning_or_error, NULL_TREE,
7100 /*integral_constant_expression_p=*/false);
7101 pop_nested_namespace (ns);
7102 arglist = tsubst (DECL_TI_ARGS (decl), args,
7103 tf_warning_or_error, NULL_TREE);
7104 template_id = lookup_template_function (fns, arglist);
7106 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7107 tmpl = determine_specialization (template_id, new_friend,
7109 /*need_member_template=*/0,
7110 TREE_VEC_LENGTH (args),
7112 return instantiate_template (tmpl, new_args, tf_error);
7115 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
7117 /* The NEW_FRIEND will look like an instantiation, to the
7118 compiler, but is not an instantiation from the point of view of
7119 the language. For example, we might have had:
7121 template <class T> struct S {
7122 template <class U> friend void f(T, U);
7125 Then, in S<int>, template <class U> void f(int, U) is not an
7126 instantiation of anything. */
7127 if (new_friend == error_mark_node)
7128 return error_mark_node;
7130 DECL_USE_TEMPLATE (new_friend) = 0;
7131 if (TREE_CODE (decl) == TEMPLATE_DECL)
7133 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
7134 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
7135 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
7138 /* The mangled name for the NEW_FRIEND is incorrect. The function
7139 is not a template instantiation and should not be mangled like
7140 one. Therefore, we forget the mangling here; we'll recompute it
7141 later if we need it. */
7142 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
7144 SET_DECL_RTL (new_friend, NULL_RTX);
7145 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
7148 if (DECL_NAMESPACE_SCOPE_P (new_friend))
7151 tree new_friend_template_info;
7152 tree new_friend_result_template_info;
7154 int new_friend_is_defn;
7156 /* We must save some information from NEW_FRIEND before calling
7157 duplicate decls since that function will free NEW_FRIEND if
7159 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
7160 new_friend_is_defn =
7161 (DECL_INITIAL (DECL_TEMPLATE_RESULT
7162 (template_for_substitution (new_friend)))
7164 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
7166 /* This declaration is a `primary' template. */
7167 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
7169 new_friend_result_template_info
7170 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
7173 new_friend_result_template_info = NULL_TREE;
7175 /* Make the init_value nonzero so pushdecl knows this is a defn. */
7176 if (new_friend_is_defn)
7177 DECL_INITIAL (new_friend) = error_mark_node;
7179 /* Inside pushdecl_namespace_level, we will push into the
7180 current namespace. However, the friend function should go
7181 into the namespace of the template. */
7182 ns = decl_namespace_context (new_friend);
7183 push_nested_namespace (ns);
7184 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
7185 pop_nested_namespace (ns);
7187 if (old_decl == error_mark_node)
7188 return error_mark_node;
7190 if (old_decl != new_friend)
7192 /* This new friend declaration matched an existing
7193 declaration. For example, given:
7195 template <class T> void f(T);
7196 template <class U> class C {
7197 template <class T> friend void f(T) {}
7200 the friend declaration actually provides the definition
7201 of `f', once C has been instantiated for some type. So,
7202 old_decl will be the out-of-class template declaration,
7203 while new_friend is the in-class definition.
7205 But, if `f' was called before this point, the
7206 instantiation of `f' will have DECL_TI_ARGS corresponding
7207 to `T' but not to `U', references to which might appear
7208 in the definition of `f'. Previously, the most general
7209 template for an instantiation of `f' was the out-of-class
7210 version; now it is the in-class version. Therefore, we
7211 run through all specialization of `f', adding to their
7212 DECL_TI_ARGS appropriately. In particular, they need a
7213 new set of outer arguments, corresponding to the
7214 arguments for this class instantiation.
7216 The same situation can arise with something like this:
7219 template <class T> class C {
7223 when `C<int>' is instantiated. Now, `f(int)' is defined
7226 if (!new_friend_is_defn)
7227 /* On the other hand, if the in-class declaration does
7228 *not* provide a definition, then we don't want to alter
7229 existing definitions. We can just leave everything
7234 tree new_template = TI_TEMPLATE (new_friend_template_info);
7235 tree new_args = TI_ARGS (new_friend_template_info);
7237 /* Overwrite whatever template info was there before, if
7238 any, with the new template information pertaining to
7240 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7242 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7243 /* We should have called reregister_specialization in
7245 gcc_assert (retrieve_specialization (new_template,
7252 /* Indicate that the old function template is a partial
7254 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7255 = new_friend_result_template_info;
7257 gcc_assert (new_template
7258 == most_general_template (new_template));
7259 gcc_assert (new_template != old_decl);
7261 /* Reassign any specializations already in the hash table
7262 to the new more general template, and add the
7263 additional template args. */
7264 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7268 tree spec = TREE_VALUE (t);
7271 elt.tmpl = old_decl;
7272 elt.args = DECL_TI_ARGS (spec);
7273 elt.spec = NULL_TREE;
7275 htab_remove_elt (decl_specializations, &elt);
7278 = add_outermost_template_args (new_args,
7279 DECL_TI_ARGS (spec));
7281 register_specialization
7282 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7285 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7289 /* The information from NEW_FRIEND has been merged into OLD_DECL
7290 by duplicate_decls. */
7291 new_friend = old_decl;
7296 tree context = DECL_CONTEXT (new_friend);
7300 template <class T> class C {
7301 template <class U> friend void C1<U>::f (); // case 1
7302 friend void C2<T>::f (); // case 2
7304 we only need to make sure CONTEXT is a complete type for
7305 case 2. To distinguish between the two cases, we note that
7306 CONTEXT of case 1 remains dependent type after tsubst while
7307 this isn't true for case 2. */
7308 ++processing_template_decl;
7309 dependent_p = dependent_type_p (context);
7310 --processing_template_decl;
7313 && !complete_type_or_else (context, NULL_TREE))
7314 return error_mark_node;
7316 if (COMPLETE_TYPE_P (context))
7318 /* Check to see that the declaration is really present, and,
7319 possibly obtain an improved declaration. */
7320 tree fn = check_classfn (context,
7321 new_friend, NULL_TREE);
7331 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7332 template arguments, as for tsubst.
7334 Returns an appropriate tsubst'd friend type or error_mark_node on
7338 tsubst_friend_class (tree friend_tmpl, tree args)
7344 context = DECL_CONTEXT (friend_tmpl);
7348 if (TREE_CODE (context) == NAMESPACE_DECL)
7349 push_nested_namespace (context);
7351 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7354 /* Look for a class template declaration. We look for hidden names
7355 because two friend declarations of the same template are the
7356 same. For example, in:
7359 template <typename> friend class F;
7361 template <typename> struct B {
7362 template <typename> friend class F;
7365 both F templates are the same. */
7366 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7367 /*block_p=*/true, 0,
7368 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7370 /* But, if we don't find one, it might be because we're in a
7371 situation like this:
7379 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7380 for `S<int>', not the TEMPLATE_DECL. */
7381 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7383 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7384 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7387 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7389 /* The friend template has already been declared. Just
7390 check to see that the declarations match, and install any new
7391 default parameters. We must tsubst the default parameters,
7392 of course. We only need the innermost template parameters
7393 because that is all that redeclare_class_template will look
7395 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7396 > TMPL_ARGS_DEPTH (args))
7399 location_t saved_input_location;
7400 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7401 args, tf_warning_or_error);
7403 saved_input_location = input_location;
7404 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7405 redeclare_class_template (TREE_TYPE (tmpl), parms);
7406 input_location = saved_input_location;
7410 friend_type = TREE_TYPE (tmpl);
7414 /* The friend template has not already been declared. In this
7415 case, the instantiation of the template class will cause the
7416 injection of this template into the global scope. */
7417 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7418 if (tmpl == error_mark_node)
7419 return error_mark_node;
7421 /* The new TMPL is not an instantiation of anything, so we
7422 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7423 the new type because that is supposed to be the corresponding
7424 template decl, i.e., TMPL. */
7425 DECL_USE_TEMPLATE (tmpl) = 0;
7426 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7427 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7428 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7429 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7431 /* Inject this template into the global scope. */
7432 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7437 if (TREE_CODE (context) == NAMESPACE_DECL)
7438 pop_nested_namespace (context);
7440 pop_nested_class ();
7446 /* Returns zero if TYPE cannot be completed later due to circularity.
7447 Otherwise returns one. */
7450 can_complete_type_without_circularity (tree type)
7452 if (type == NULL_TREE || type == error_mark_node)
7454 else if (COMPLETE_TYPE_P (type))
7456 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7457 return can_complete_type_without_circularity (TREE_TYPE (type));
7458 else if (CLASS_TYPE_P (type)
7459 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7465 /* Apply any attributes which had to be deferred until instantiation
7466 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7467 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7470 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7471 tree args, tsubst_flags_t complain, tree in_decl)
7473 tree last_dep = NULL_TREE;
7477 for (t = attributes; t; t = TREE_CHAIN (t))
7478 if (ATTR_IS_DEPENDENT (t))
7481 attributes = copy_list (attributes);
7485 if (DECL_P (*decl_p))
7487 if (TREE_TYPE (*decl_p) == error_mark_node)
7489 p = &DECL_ATTRIBUTES (*decl_p);
7492 p = &TYPE_ATTRIBUTES (*decl_p);
7496 tree late_attrs = NULL_TREE;
7497 tree *q = &late_attrs;
7499 for (*p = attributes; *p; )
7502 if (ATTR_IS_DEPENDENT (t))
7504 *p = TREE_CHAIN (t);
7505 TREE_CHAIN (t) = NULL_TREE;
7506 /* If the first attribute argument is an identifier, don't
7507 pass it through tsubst. Attributes like mode, format,
7508 cleanup and several target specific attributes expect it
7511 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7512 && TREE_VALUE (TREE_VALUE (t))
7513 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7514 == IDENTIFIER_NODE))
7517 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7519 /*integral_constant_expression_p=*/false);
7520 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7522 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7527 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7528 /*integral_constant_expression_p=*/false);
7530 q = &TREE_CHAIN (t);
7533 p = &TREE_CHAIN (t);
7536 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7540 /* Perform (or defer) access check for typedefs that were referenced
7541 from within the template TMPL code.
7542 This is a subroutine of instantiate_template and instantiate_class_template.
7543 TMPL is the template to consider and TARGS is the list of arguments of
7547 perform_typedefs_access_check (tree tmpl, tree targs)
7549 location_t saved_location;
7551 qualified_typedef_usage_t *iter;
7554 || (!CLASS_TYPE_P (tmpl)
7555 && TREE_CODE (tmpl) != FUNCTION_DECL))
7558 saved_location = input_location;
7560 VEC_iterate (qualified_typedef_usage_t,
7561 get_types_needing_access_check (tmpl),
7565 tree type_decl = iter->typedef_decl;
7566 tree type_scope = iter->context;
7568 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7571 if (uses_template_parms (type_decl))
7572 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7573 if (uses_template_parms (type_scope))
7574 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7576 /* Make access check error messages point to the location
7577 of the use of the typedef. */
7578 input_location = iter->locus;
7579 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7580 type_decl, type_decl);
7582 input_location = saved_location;
7586 instantiate_class_template (tree type)
7588 tree templ, args, pattern, t, member;
7592 unsigned int saved_maximum_field_alignment;
7594 if (type == error_mark_node)
7595 return error_mark_node;
7597 if (TYPE_BEING_DEFINED (type)
7598 || COMPLETE_TYPE_P (type)
7599 || uses_template_parms (type))
7602 /* Figure out which template is being instantiated. */
7603 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7604 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7606 /* Determine what specialization of the original template to
7608 t = most_specialized_class (type, templ);
7609 if (t == error_mark_node)
7611 TYPE_BEING_DEFINED (type) = 1;
7612 return error_mark_node;
7616 /* This TYPE is actually an instantiation of a partial
7617 specialization. We replace the innermost set of ARGS with
7618 the arguments appropriate for substitution. For example,
7621 template <class T> struct S {};
7622 template <class T> struct S<T*> {};
7624 and supposing that we are instantiating S<int*>, ARGS will
7625 presently be {int*} -- but we need {int}. */
7626 pattern = TREE_TYPE (t);
7627 args = TREE_PURPOSE (t);
7631 pattern = TREE_TYPE (templ);
7632 args = CLASSTYPE_TI_ARGS (type);
7635 /* If the template we're instantiating is incomplete, then clearly
7636 there's nothing we can do. */
7637 if (!COMPLETE_TYPE_P (pattern))
7640 /* If we've recursively instantiated too many templates, stop. */
7641 if (! push_tinst_level (type))
7644 /* Now we're really doing the instantiation. Mark the type as in
7645 the process of being defined. */
7646 TYPE_BEING_DEFINED (type) = 1;
7648 /* We may be in the middle of deferred access check. Disable
7650 push_deferring_access_checks (dk_no_deferred);
7652 push_to_top_level ();
7653 /* Use #pragma pack from the template context. */
7654 saved_maximum_field_alignment = maximum_field_alignment;
7655 maximum_field_alignment = TYPE_PRECISION (pattern);
7657 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7659 /* Set the input location to the most specialized template definition.
7660 This is needed if tsubsting causes an error. */
7661 typedecl = TYPE_MAIN_DECL (pattern);
7662 input_location = DECL_SOURCE_LOCATION (typedecl);
7664 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7665 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7666 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7667 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7668 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7669 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7670 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7671 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7672 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7673 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7674 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7675 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7676 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7677 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7678 if (ANON_AGGR_TYPE_P (pattern))
7679 SET_ANON_AGGR_TYPE_P (type);
7680 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7682 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7683 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7686 pbinfo = TYPE_BINFO (pattern);
7688 /* We should never instantiate a nested class before its enclosing
7689 class; we need to look up the nested class by name before we can
7690 instantiate it, and that lookup should instantiate the enclosing
7692 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7693 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7694 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7696 base_list = NULL_TREE;
7697 if (BINFO_N_BASE_BINFOS (pbinfo))
7700 tree context = TYPE_CONTEXT (type);
7704 /* We must enter the scope containing the type, as that is where
7705 the accessibility of types named in dependent bases are
7707 pushed_scope = push_scope (context ? context : global_namespace);
7709 /* Substitute into each of the bases to determine the actual
7711 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7714 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7715 tree expanded_bases = NULL_TREE;
7718 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7721 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7722 args, tf_error, NULL_TREE);
7723 if (expanded_bases == error_mark_node)
7726 len = TREE_VEC_LENGTH (expanded_bases);
7729 for (idx = 0; idx < len; idx++)
7732 /* Extract the already-expanded base class. */
7733 base = TREE_VEC_ELT (expanded_bases, idx);
7735 /* Substitute to figure out the base class. */
7736 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7739 if (base == error_mark_node)
7742 base_list = tree_cons (access, base, base_list);
7743 if (BINFO_VIRTUAL_P (pbase_binfo))
7744 TREE_TYPE (base_list) = integer_type_node;
7748 /* The list is now in reverse order; correct that. */
7749 base_list = nreverse (base_list);
7752 pop_scope (pushed_scope);
7754 /* Now call xref_basetypes to set up all the base-class
7756 xref_basetypes (type, base_list);
7758 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7759 (int) ATTR_FLAG_TYPE_IN_PLACE,
7760 args, tf_error, NULL_TREE);
7762 /* Now that our base classes are set up, enter the scope of the
7763 class, so that name lookups into base classes, etc. will work
7764 correctly. This is precisely analogous to what we do in
7765 begin_class_definition when defining an ordinary non-template
7766 class, except we also need to push the enclosing classes. */
7767 push_nested_class (type);
7769 /* Now members are processed in the order of declaration. */
7770 for (member = CLASSTYPE_DECL_LIST (pattern);
7771 member; member = TREE_CHAIN (member))
7773 tree t = TREE_VALUE (member);
7775 if (TREE_PURPOSE (member))
7779 /* Build new CLASSTYPE_NESTED_UTDS. */
7782 bool class_template_p;
7784 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7785 && TYPE_LANG_SPECIFIC (t)
7786 && CLASSTYPE_IS_TEMPLATE (t));
7787 /* If the member is a class template, then -- even after
7788 substitution -- there may be dependent types in the
7789 template argument list for the class. We increment
7790 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7791 that function will assume that no types are dependent
7792 when outside of a template. */
7793 if (class_template_p)
7794 ++processing_template_decl;
7795 newtag = tsubst (t, args, tf_error, NULL_TREE);
7796 if (class_template_p)
7797 --processing_template_decl;
7798 if (newtag == error_mark_node)
7801 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7803 tree name = TYPE_IDENTIFIER (t);
7805 if (class_template_p)
7806 /* Unfortunately, lookup_template_class sets
7807 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7808 instantiation (i.e., for the type of a member
7809 template class nested within a template class.)
7810 This behavior is required for
7811 maybe_process_partial_specialization to work
7812 correctly, but is not accurate in this case;
7813 the TAG is not an instantiation of anything.
7814 (The corresponding TEMPLATE_DECL is an
7815 instantiation, but the TYPE is not.) */
7816 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7818 /* Now, we call pushtag to put this NEWTAG into the scope of
7819 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7820 pushtag calling push_template_decl. We don't have to do
7821 this for enums because it will already have been done in
7824 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7825 pushtag (name, newtag, /*tag_scope=*/ts_current);
7828 else if (TREE_CODE (t) == FUNCTION_DECL
7829 || DECL_FUNCTION_TEMPLATE_P (t))
7831 /* Build new TYPE_METHODS. */
7834 if (TREE_CODE (t) == TEMPLATE_DECL)
7835 ++processing_template_decl;
7836 r = tsubst (t, args, tf_error, NULL_TREE);
7837 if (TREE_CODE (t) == TEMPLATE_DECL)
7838 --processing_template_decl;
7839 set_current_access_from_decl (r);
7840 finish_member_declaration (r);
7844 /* Build new TYPE_FIELDS. */
7845 if (TREE_CODE (t) == STATIC_ASSERT)
7848 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7849 tf_warning_or_error, NULL_TREE,
7850 /*integral_constant_expression_p=*/true);
7851 finish_static_assert (condition,
7852 STATIC_ASSERT_MESSAGE (t),
7853 STATIC_ASSERT_SOURCE_LOCATION (t),
7856 else if (TREE_CODE (t) != CONST_DECL)
7860 /* The file and line for this declaration, to
7861 assist in error message reporting. Since we
7862 called push_tinst_level above, we don't need to
7864 input_location = DECL_SOURCE_LOCATION (t);
7866 if (TREE_CODE (t) == TEMPLATE_DECL)
7867 ++processing_template_decl;
7868 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7869 if (TREE_CODE (t) == TEMPLATE_DECL)
7870 --processing_template_decl;
7871 if (TREE_CODE (r) == VAR_DECL)
7875 [t]he initialization (and any associated
7876 side-effects) of a static data member does
7877 not occur unless the static data member is
7878 itself used in a way that requires the
7879 definition of the static data member to
7882 Therefore, we do not substitute into the
7883 initialized for the static data member here. */
7884 finish_static_data_member_decl
7887 /*init_const_expr_p=*/false,
7888 /*asmspec_tree=*/NULL_TREE,
7890 if (DECL_INITIALIZED_IN_CLASS_P (r))
7891 check_static_variable_definition (r, TREE_TYPE (r));
7893 else if (TREE_CODE (r) == FIELD_DECL)
7895 /* Determine whether R has a valid type and can be
7896 completed later. If R is invalid, then it is
7897 replaced by error_mark_node so that it will not be
7898 added to TYPE_FIELDS. */
7899 tree rtype = TREE_TYPE (r);
7900 if (can_complete_type_without_circularity (rtype))
7901 complete_type (rtype);
7903 if (!COMPLETE_TYPE_P (rtype))
7905 cxx_incomplete_type_error (r, rtype);
7906 r = error_mark_node;
7910 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7911 such a thing will already have been added to the field
7912 list by tsubst_enum in finish_member_declaration in the
7913 CLASSTYPE_NESTED_UTDS case above. */
7914 if (!(TREE_CODE (r) == TYPE_DECL
7915 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7916 && DECL_ARTIFICIAL (r)))
7918 set_current_access_from_decl (r);
7919 finish_member_declaration (r);
7926 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7928 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7930 tree friend_type = t;
7931 bool adjust_processing_template_decl = false;
7933 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7935 /* template <class T> friend class C; */
7936 friend_type = tsubst_friend_class (friend_type, args);
7937 adjust_processing_template_decl = true;
7939 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7941 /* template <class T> friend class C::D; */
7942 friend_type = tsubst (friend_type, args,
7943 tf_warning_or_error, NULL_TREE);
7944 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7945 friend_type = TREE_TYPE (friend_type);
7946 adjust_processing_template_decl = true;
7948 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7950 /* This could be either
7954 when dependent_type_p is false or
7956 template <class U> friend class T::C;
7959 friend_type = tsubst (friend_type, args,
7960 tf_warning_or_error, NULL_TREE);
7961 /* Bump processing_template_decl for correct
7962 dependent_type_p calculation. */
7963 ++processing_template_decl;
7964 if (dependent_type_p (friend_type))
7965 adjust_processing_template_decl = true;
7966 --processing_template_decl;
7968 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7969 && hidden_name_p (TYPE_NAME (friend_type)))
7973 where C hasn't been declared yet. Let's lookup name
7974 from namespace scope directly, bypassing any name that
7975 come from dependent base class. */
7976 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7978 /* The call to xref_tag_from_type does injection for friend
7980 push_nested_namespace (ns);
7982 xref_tag_from_type (friend_type, NULL_TREE,
7983 /*tag_scope=*/ts_current);
7984 pop_nested_namespace (ns);
7986 else if (uses_template_parms (friend_type))
7987 /* friend class C<T>; */
7988 friend_type = tsubst (friend_type, args,
7989 tf_warning_or_error, NULL_TREE);
7994 where C is already declared or
7996 friend class C<int>;
7998 We don't have to do anything in these cases. */
8000 if (adjust_processing_template_decl)
8001 /* Trick make_friend_class into realizing that the friend
8002 we're adding is a template, not an ordinary class. It's
8003 important that we use make_friend_class since it will
8004 perform some error-checking and output cross-reference
8006 ++processing_template_decl;
8008 if (friend_type != error_mark_node)
8009 make_friend_class (type, friend_type, /*complain=*/false);
8011 if (adjust_processing_template_decl)
8012 --processing_template_decl;
8016 /* Build new DECL_FRIENDLIST. */
8019 /* The file and line for this declaration, to
8020 assist in error message reporting. Since we
8021 called push_tinst_level above, we don't need to
8023 input_location = DECL_SOURCE_LOCATION (t);
8025 if (TREE_CODE (t) == TEMPLATE_DECL)
8027 ++processing_template_decl;
8028 push_deferring_access_checks (dk_no_check);
8031 r = tsubst_friend_function (t, args);
8032 add_friend (type, r, /*complain=*/false);
8033 if (TREE_CODE (t) == TEMPLATE_DECL)
8035 pop_deferring_access_checks ();
8036 --processing_template_decl;
8042 /* Set the file and line number information to whatever is given for
8043 the class itself. This puts error messages involving generated
8044 implicit functions at a predictable point, and the same point
8045 that would be used for non-template classes. */
8046 input_location = DECL_SOURCE_LOCATION (typedecl);
8048 unreverse_member_declarations (type);
8049 finish_struct_1 (type);
8050 TYPE_BEING_DEFINED (type) = 0;
8052 /* Now that the class is complete, instantiate default arguments for
8053 any member functions. We don't do this earlier because the
8054 default arguments may reference members of the class. */
8055 if (!PRIMARY_TEMPLATE_P (templ))
8056 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
8057 if (TREE_CODE (t) == FUNCTION_DECL
8058 /* Implicitly generated member functions will not have template
8059 information; they are not instantiations, but instead are
8060 created "fresh" for each instantiation. */
8061 && DECL_TEMPLATE_INFO (t))
8062 tsubst_default_arguments (t);
8064 /* Some typedefs referenced from within the template code need to be access
8065 checked at template instantiation time, i.e now. These types were
8066 added to the template at parsing time. Let's get those and perform
8067 the access checks then. */
8068 perform_typedefs_access_check (pattern, args);
8069 perform_deferred_access_checks ();
8070 pop_nested_class ();
8071 maximum_field_alignment = saved_maximum_field_alignment;
8072 pop_from_top_level ();
8073 pop_deferring_access_checks ();
8076 /* The vtable for a template class can be emitted in any translation
8077 unit in which the class is instantiated. When there is no key
8078 method, however, finish_struct_1 will already have added TYPE to
8079 the keyed_classes list. */
8080 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
8081 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
8087 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8093 else if (TYPE_P (t))
8094 r = tsubst (t, args, complain, in_decl);
8097 r = tsubst_expr (t, args, complain, in_decl,
8098 /*integral_constant_expression_p=*/true);
8099 r = fold_non_dependent_expr (r);
8104 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
8105 NONTYPE_ARGUMENT_PACK. */
8108 make_fnparm_pack (tree spec_parm)
8110 /* Collect all of the extra "packed" parameters into an
8114 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
8115 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
8116 int i, len = list_length (spec_parm);
8118 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
8119 parmvec = make_tree_vec (len);
8120 parmtypevec = make_tree_vec (len);
8121 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
8123 TREE_VEC_ELT (parmvec, i) = spec_parm;
8124 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
8127 /* Build the argument packs. */
8128 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
8129 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
8130 TREE_TYPE (argpack) = argtypepack;
8135 /* Substitute ARGS into T, which is an pack expansion
8136 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
8137 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
8138 (if only a partial substitution could be performed) or
8139 ERROR_MARK_NODE if there was an error. */
8141 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
8145 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
8149 bool very_local_specializations = false;
8151 gcc_assert (PACK_EXPANSION_P (t));
8152 pattern = PACK_EXPANSION_PATTERN (t);
8154 /* Determine the argument packs that will instantiate the parameter
8155 packs used in the expansion expression. While we're at it,
8156 compute the number of arguments to be expanded and make sure it
8158 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
8159 pack = TREE_CHAIN (pack))
8161 tree parm_pack = TREE_VALUE (pack);
8162 tree arg_pack = NULL_TREE;
8163 tree orig_arg = NULL_TREE;
8165 if (TREE_CODE (parm_pack) == PARM_DECL)
8167 arg_pack = retrieve_local_specialization (parm_pack);
8168 if (arg_pack == NULL_TREE)
8170 /* This can happen for a parameter name used later in a function
8171 declaration (such as in a late-specified return type). Just
8172 make a dummy decl, since it's only used for its type. */
8173 gcc_assert (cp_unevaluated_operand != 0);
8174 arg_pack = tsubst_decl (parm_pack, args, complain);
8175 arg_pack = make_fnparm_pack (arg_pack);
8180 int level, idx, levels;
8181 template_parm_level_and_index (parm_pack, &level, &idx);
8183 levels = TMPL_ARGS_DEPTH (args);
8184 if (level <= levels)
8185 arg_pack = TMPL_ARG (args, level, idx);
8188 orig_arg = arg_pack;
8189 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
8190 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
8192 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
8193 /* This can only happen if we forget to expand an argument
8194 pack somewhere else. Just return an error, silently. */
8196 result = make_tree_vec (1);
8197 TREE_VEC_ELT (result, 0) = error_mark_node;
8202 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
8203 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
8205 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
8206 tree pattern = PACK_EXPANSION_PATTERN (expansion);
8207 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
8208 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
8209 /* The argument pack that the parameter maps to is just an
8210 expansion of the parameter itself, such as one would
8211 find in the implicit typedef of a class inside the
8212 class itself. Consider this parameter "unsubstituted",
8213 so that we will maintain the outer pack expansion. */
8214 arg_pack = NULL_TREE;
8220 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
8222 /* It's all-or-nothing with incomplete argument packs. */
8223 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8224 return error_mark_node;
8226 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
8231 else if (len != my_len)
8234 /* We got explicit args for some packs but not others;
8235 do nothing now and try again after deduction. */
8237 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8238 error ("mismatched argument pack lengths while expanding "
8242 error ("mismatched argument pack lengths while expanding "
8245 return error_mark_node;
8248 /* Keep track of the parameter packs and their corresponding
8250 packs = tree_cons (parm_pack, arg_pack, packs);
8251 TREE_TYPE (packs) = orig_arg;
8254 /* We can't substitute for this parameter pack. */
8255 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8257 unsubstituted_packs);
8260 /* We cannot expand this expansion expression, because we don't have
8261 all of the argument packs we need. Substitute into the pattern
8262 and return a PACK_EXPANSION_*. The caller will need to deal with
8264 if (unsubstituted_packs)
8267 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8268 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8269 /*integral_constant_expression_p=*/false);
8271 new_pat = tsubst (pattern, args, complain, in_decl);
8272 return make_pack_expansion (new_pat);
8275 /* We could not find any argument packs that work. */
8277 return error_mark_node;
8279 if (!local_specializations)
8281 /* We're in a late-specified return type, so we don't have a local
8282 specializations table. Create one for doing this expansion. */
8283 very_local_specializations = true;
8284 local_specializations = htab_create (37,
8285 hash_local_specialization,
8286 eq_local_specializations,
8290 /* For each argument in each argument pack, substitute into the
8292 result = make_tree_vec (len + incomplete);
8293 for (i = 0; i < len + incomplete; ++i)
8295 /* For parameter pack, change the substitution of the parameter
8296 pack to the ith argument in its argument pack, then expand
8298 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8300 tree parm = TREE_PURPOSE (pack);
8302 if (TREE_CODE (parm) == PARM_DECL)
8304 /* Select the Ith argument from the pack. */
8305 tree arg = make_node (ARGUMENT_PACK_SELECT);
8306 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8307 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8309 register_local_specialization (arg, parm);
8315 template_parm_level_and_index (parm, &level, &idx);
8319 /* Select the Ith argument from the pack. */
8320 value = make_node (ARGUMENT_PACK_SELECT);
8321 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8322 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8325 /* Update the corresponding argument. */
8326 TMPL_ARG (args, level, idx) = value;
8330 /* Substitute into the PATTERN with the altered arguments. */
8331 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8332 TREE_VEC_ELT (result, i) =
8333 tsubst_expr (pattern, args, complain, in_decl,
8334 /*integral_constant_expression_p=*/false);
8336 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8339 /* When we have incomplete argument packs, the last "expanded"
8340 result is itself a pack expansion, which allows us
8341 to deduce more arguments. */
8342 TREE_VEC_ELT (result, i) =
8343 make_pack_expansion (TREE_VEC_ELT (result, i));
8345 if (TREE_VEC_ELT (result, i) == error_mark_node)
8347 result = error_mark_node;
8352 /* Update ARGS to restore the substitution from parameter packs to
8353 their argument packs. */
8354 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8356 tree parm = TREE_PURPOSE (pack);
8358 if (TREE_CODE (parm) == PARM_DECL)
8359 register_local_specialization (TREE_TYPE (pack), parm);
8363 template_parm_level_and_index (parm, &level, &idx);
8365 /* Update the corresponding argument. */
8366 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8367 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8370 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8374 if (very_local_specializations)
8376 htab_delete (local_specializations);
8377 local_specializations = NULL;
8383 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8384 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8385 parameter packs; all parms generated from a function parameter pack will
8386 have the same DECL_PARM_INDEX. */
8389 get_pattern_parm (tree parm, tree tmpl)
8391 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8394 if (DECL_ARTIFICIAL (parm))
8396 for (patparm = DECL_ARGUMENTS (pattern);
8397 patparm; patparm = TREE_CHAIN (patparm))
8398 if (DECL_ARTIFICIAL (patparm)
8399 && DECL_NAME (parm) == DECL_NAME (patparm))
8404 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8405 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8406 gcc_assert (DECL_PARM_INDEX (patparm)
8407 == DECL_PARM_INDEX (parm));
8413 /* Substitute ARGS into the vector or list of template arguments T. */
8416 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8419 int len = TREE_VEC_LENGTH (t);
8420 int need_new = 0, i, expanded_len_adjust = 0, out;
8421 tree *elts = (tree *) alloca (len * sizeof (tree));
8423 for (i = 0; i < len; i++)
8425 tree orig_arg = TREE_VEC_ELT (t, i);
8428 if (TREE_CODE (orig_arg) == TREE_VEC)
8429 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8430 else if (PACK_EXPANSION_P (orig_arg))
8432 /* Substitute into an expansion expression. */
8433 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8435 if (TREE_CODE (new_arg) == TREE_VEC)
8436 /* Add to the expanded length adjustment the number of
8437 expanded arguments. We subtract one from this
8438 measurement, because the argument pack expression
8439 itself is already counted as 1 in
8440 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8441 the argument pack is empty. */
8442 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8444 else if (ARGUMENT_PACK_P (orig_arg))
8446 /* Substitute into each of the arguments. */
8447 new_arg = TYPE_P (orig_arg)
8448 ? cxx_make_type (TREE_CODE (orig_arg))
8449 : make_node (TREE_CODE (orig_arg));
8451 SET_ARGUMENT_PACK_ARGS (
8453 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8454 args, complain, in_decl));
8456 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8457 new_arg = error_mark_node;
8459 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8460 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8462 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8464 if (TREE_TYPE (new_arg) == error_mark_node)
8465 new_arg = error_mark_node;
8469 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8471 if (new_arg == error_mark_node)
8472 return error_mark_node;
8475 if (new_arg != orig_arg)
8482 /* Make space for the expanded arguments coming from template
8484 t = make_tree_vec (len + expanded_len_adjust);
8485 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
8486 arguments for a member template.
8487 In that case each TREE_VEC in ORIG_T represents a level of template
8488 arguments, and ORIG_T won't carry any non defaulted argument count.
8489 It will rather be the nested TREE_VECs that will carry one.
8490 In other words, ORIG_T carries a non defaulted argument count only
8491 if it doesn't contain any nested TREE_VEC. */
8492 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
8494 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
8495 count += expanded_len_adjust;
8496 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
8498 for (i = 0, out = 0; i < len; i++)
8500 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8501 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8502 && TREE_CODE (elts[i]) == TREE_VEC)
8506 /* Now expand the template argument pack "in place". */
8507 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8508 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8512 TREE_VEC_ELT (t, out) = elts[i];
8520 /* Return the result of substituting ARGS into the template parameters
8521 given by PARMS. If there are m levels of ARGS and m + n levels of
8522 PARMS, then the result will contain n levels of PARMS. For
8523 example, if PARMS is `template <class T> template <class U>
8524 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8525 result will be `template <int*, double, class V>'. */
8528 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8533 /* When substituting into a template, we must set
8534 PROCESSING_TEMPLATE_DECL as the template parameters may be
8535 dependent if they are based on one-another, and the dependency
8536 predicates are short-circuit outside of templates. */
8537 ++processing_template_decl;
8539 for (new_parms = &r;
8540 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8541 new_parms = &(TREE_CHAIN (*new_parms)),
8542 parms = TREE_CHAIN (parms))
8545 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8548 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8554 if (parms == error_mark_node)
8557 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8559 if (tuple == error_mark_node)
8562 default_value = TREE_PURPOSE (tuple);
8563 parm_decl = TREE_VALUE (tuple);
8565 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8566 if (TREE_CODE (parm_decl) == PARM_DECL
8567 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8568 parm_decl = error_mark_node;
8569 default_value = tsubst_template_arg (default_value, args,
8570 complain, NULL_TREE);
8572 tuple = build_tree_list (default_value, parm_decl);
8573 TREE_VEC_ELT (new_vec, i) = tuple;
8577 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8578 - TMPL_ARGS_DEPTH (args)),
8579 new_vec, NULL_TREE);
8582 --processing_template_decl;
8587 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8588 type T. If T is not an aggregate or enumeration type, it is
8589 handled as if by tsubst. IN_DECL is as for tsubst. If
8590 ENTERING_SCOPE is nonzero, T is the context for a template which
8591 we are presently tsubst'ing. Return the substituted value. */
8594 tsubst_aggr_type (tree t,
8596 tsubst_flags_t complain,
8603 switch (TREE_CODE (t))
8606 if (TYPE_PTRMEMFUNC_P (t))
8607 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8609 /* Else fall through. */
8612 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8617 int saved_unevaluated_operand;
8618 int saved_inhibit_evaluation_warnings;
8620 /* In "sizeof(X<I>)" we need to evaluate "I". */
8621 saved_unevaluated_operand = cp_unevaluated_operand;
8622 cp_unevaluated_operand = 0;
8623 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8624 c_inhibit_evaluation_warnings = 0;
8626 /* First, determine the context for the type we are looking
8628 context = TYPE_CONTEXT (t);
8631 context = tsubst_aggr_type (context, args, complain,
8632 in_decl, /*entering_scope=*/1);
8633 /* If context is a nested class inside a class template,
8634 it may still need to be instantiated (c++/33959). */
8635 if (TYPE_P (context))
8636 context = complete_type (context);
8639 /* Then, figure out what arguments are appropriate for the
8640 type we are trying to find. For example, given:
8642 template <class T> struct S;
8643 template <class T, class U> void f(T, U) { S<U> su; }
8645 and supposing that we are instantiating f<int, double>,
8646 then our ARGS will be {int, double}, but, when looking up
8647 S we only want {double}. */
8648 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8650 if (argvec == error_mark_node)
8651 r = error_mark_node;
8654 r = lookup_template_class (t, argvec, in_decl, context,
8655 entering_scope, complain);
8656 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8659 cp_unevaluated_operand = saved_unevaluated_operand;
8660 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8665 /* This is not a template type, so there's nothing to do. */
8669 return tsubst (t, args, complain, in_decl);
8673 /* Substitute into the default argument ARG (a default argument for
8674 FN), which has the indicated TYPE. */
8677 tsubst_default_argument (tree fn, tree type, tree arg)
8679 tree saved_class_ptr = NULL_TREE;
8680 tree saved_class_ref = NULL_TREE;
8682 /* This default argument came from a template. Instantiate the
8683 default argument here, not in tsubst. In the case of
8692 we must be careful to do name lookup in the scope of S<T>,
8693 rather than in the current class. */
8694 push_access_scope (fn);
8695 /* The "this" pointer is not valid in a default argument. */
8698 saved_class_ptr = current_class_ptr;
8699 cp_function_chain->x_current_class_ptr = NULL_TREE;
8700 saved_class_ref = current_class_ref;
8701 cp_function_chain->x_current_class_ref = NULL_TREE;
8704 push_deferring_access_checks(dk_no_deferred);
8705 /* The default argument expression may cause implicitly defined
8706 member functions to be synthesized, which will result in garbage
8707 collection. We must treat this situation as if we were within
8708 the body of function so as to avoid collecting live data on the
8711 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8712 tf_warning_or_error, NULL_TREE,
8713 /*integral_constant_expression_p=*/false);
8715 pop_deferring_access_checks();
8717 /* Restore the "this" pointer. */
8720 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8721 cp_function_chain->x_current_class_ref = saved_class_ref;
8724 /* Make sure the default argument is reasonable. */
8725 arg = check_default_argument (type, arg);
8727 pop_access_scope (fn);
8732 /* Substitute into all the default arguments for FN. */
8735 tsubst_default_arguments (tree fn)
8740 tmpl_args = DECL_TI_ARGS (fn);
8742 /* If this function is not yet instantiated, we certainly don't need
8743 its default arguments. */
8744 if (uses_template_parms (tmpl_args))
8747 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8749 arg = TREE_CHAIN (arg))
8750 if (TREE_PURPOSE (arg))
8751 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8753 TREE_PURPOSE (arg));
8756 /* Substitute the ARGS into the T, which is a _DECL. Return the
8757 result of the substitution. Issue error and warning messages under
8758 control of COMPLAIN. */
8761 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8763 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8764 location_t saved_loc;
8769 /* Set the filename and linenumber to improve error-reporting. */
8770 saved_loc = input_location;
8771 input_location = DECL_SOURCE_LOCATION (t);
8773 switch (TREE_CODE (t))
8777 /* We can get here when processing a member function template,
8778 member class template, or template template parameter. */
8779 tree decl = DECL_TEMPLATE_RESULT (t);
8784 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8786 /* Template template parameter is treated here. */
8787 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8788 if (new_type == error_mark_node)
8789 RETURN (error_mark_node);
8792 TREE_CHAIN (r) = NULL_TREE;
8793 TREE_TYPE (r) = new_type;
8794 DECL_TEMPLATE_RESULT (r)
8795 = build_decl (DECL_SOURCE_LOCATION (decl),
8796 TYPE_DECL, DECL_NAME (decl), new_type);
8797 DECL_TEMPLATE_PARMS (r)
8798 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8800 TYPE_NAME (new_type) = r;
8804 /* We might already have an instance of this template.
8805 The ARGS are for the surrounding class type, so the
8806 full args contain the tsubst'd args for the context,
8807 plus the innermost args from the template decl. */
8808 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8809 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8810 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8811 /* Because this is a template, the arguments will still be
8812 dependent, even after substitution. If
8813 PROCESSING_TEMPLATE_DECL is not set, the dependency
8814 predicates will short-circuit. */
8815 ++processing_template_decl;
8816 full_args = tsubst_template_args (tmpl_args, args,
8818 --processing_template_decl;
8819 if (full_args == error_mark_node)
8820 RETURN (error_mark_node);
8822 /* If this is a default template template argument,
8823 tsubst might not have changed anything. */
8824 if (full_args == tmpl_args)
8827 hash = hash_tmpl_and_args (t, full_args);
8828 spec = retrieve_specialization (t, full_args, hash);
8829 if (spec != NULL_TREE)
8835 /* Make a new template decl. It will be similar to the
8836 original, but will record the current template arguments.
8837 We also create a new function declaration, which is just
8838 like the old one, but points to this new template, rather
8839 than the old one. */
8841 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8842 TREE_CHAIN (r) = NULL_TREE;
8844 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
8846 if (TREE_CODE (decl) == TYPE_DECL)
8849 ++processing_template_decl;
8850 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8851 --processing_template_decl;
8852 if (new_type == error_mark_node)
8853 RETURN (error_mark_node);
8855 TREE_TYPE (r) = new_type;
8856 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8857 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8858 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8859 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8864 ++processing_template_decl;
8865 new_decl = tsubst (decl, args, complain, in_decl);
8866 --processing_template_decl;
8867 if (new_decl == error_mark_node)
8868 RETURN (error_mark_node);
8870 DECL_TEMPLATE_RESULT (r) = new_decl;
8871 DECL_TI_TEMPLATE (new_decl) = r;
8872 TREE_TYPE (r) = TREE_TYPE (new_decl);
8873 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8874 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8877 SET_DECL_IMPLICIT_INSTANTIATION (r);
8878 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8879 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8881 /* The template parameters for this new template are all the
8882 template parameters for the old template, except the
8883 outermost level of parameters. */
8884 DECL_TEMPLATE_PARMS (r)
8885 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8888 if (PRIMARY_TEMPLATE_P (t))
8889 DECL_PRIMARY_TEMPLATE (r) = r;
8891 if (TREE_CODE (decl) != TYPE_DECL)
8892 /* Record this non-type partial instantiation. */
8893 register_specialization (r, t,
8894 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8902 tree argvec = NULL_TREE;
8910 /* Nobody should be tsubst'ing into non-template functions. */
8911 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8913 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8918 /* If T is not dependent, just return it. We have to
8919 increment PROCESSING_TEMPLATE_DECL because
8920 value_dependent_expression_p assumes that nothing is
8921 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8922 ++processing_template_decl;
8923 dependent_p = value_dependent_expression_p (t);
8924 --processing_template_decl;
8928 /* Calculate the most general template of which R is a
8929 specialization, and the complete set of arguments used to
8931 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8932 argvec = tsubst_template_args (DECL_TI_ARGS
8933 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8934 args, complain, in_decl);
8936 /* Check to see if we already have this specialization. */
8937 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8938 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8946 /* We can see more levels of arguments than parameters if
8947 there was a specialization of a member template, like
8950 template <class T> struct S { template <class U> void f(); }
8951 template <> template <class U> void S<int>::f(U);
8953 Here, we'll be substituting into the specialization,
8954 because that's where we can find the code we actually
8955 want to generate, but we'll have enough arguments for
8956 the most general template.
8958 We also deal with the peculiar case:
8960 template <class T> struct S {
8961 template <class U> friend void f();
8963 template <class U> void f() {}
8965 template void f<double>();
8967 Here, the ARGS for the instantiation of will be {int,
8968 double}. But, we only need as many ARGS as there are
8969 levels of template parameters in CODE_PATTERN. We are
8970 careful not to get fooled into reducing the ARGS in
8973 template <class T> struct S { template <class U> void f(U); }
8974 template <class T> template <> void S<T>::f(int) {}
8976 which we can spot because the pattern will be a
8977 specialization in this case. */
8978 args_depth = TMPL_ARGS_DEPTH (args);
8980 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8981 if (args_depth > parms_depth
8982 && !DECL_TEMPLATE_SPECIALIZATION (t))
8983 args = get_innermost_template_args (args, parms_depth);
8987 /* This special case arises when we have something like this:
8989 template <class T> struct S {
8990 friend void f<int>(int, double);
8993 Here, the DECL_TI_TEMPLATE for the friend declaration
8994 will be an IDENTIFIER_NODE. We are being called from
8995 tsubst_friend_function, and we want only to create a
8996 new decl (R) with appropriate types so that we can call
8997 determine_specialization. */
8998 gen_tmpl = NULL_TREE;
9001 if (DECL_CLASS_SCOPE_P (t))
9003 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
9007 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
9008 complain, t, /*entering_scope=*/1);
9013 ctx = DECL_CONTEXT (t);
9015 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9016 if (type == error_mark_node)
9017 RETURN (error_mark_node);
9019 /* We do NOT check for matching decls pushed separately at this
9020 point, as they may not represent instantiations of this
9021 template, and in any case are considered separate under the
9024 DECL_USE_TEMPLATE (r) = 0;
9025 TREE_TYPE (r) = type;
9026 /* Clear out the mangled name and RTL for the instantiation. */
9027 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9028 SET_DECL_RTL (r, NULL_RTX);
9029 /* Leave DECL_INITIAL set on deleted instantiations. */
9030 if (!DECL_DELETED_FN (r))
9031 DECL_INITIAL (r) = NULL_TREE;
9032 DECL_CONTEXT (r) = ctx;
9034 if (member && DECL_CONV_FN_P (r))
9035 /* Type-conversion operator. Reconstruct the name, in
9036 case it's the name of one of the template's parameters. */
9037 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
9039 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
9041 DECL_RESULT (r) = NULL_TREE;
9043 TREE_STATIC (r) = 0;
9044 TREE_PUBLIC (r) = TREE_PUBLIC (t);
9045 DECL_EXTERNAL (r) = 1;
9046 /* If this is an instantiation of a function with internal
9047 linkage, we already know what object file linkage will be
9048 assigned to the instantiation. */
9049 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
9050 DECL_DEFER_OUTPUT (r) = 0;
9051 TREE_CHAIN (r) = NULL_TREE;
9052 DECL_PENDING_INLINE_INFO (r) = 0;
9053 DECL_PENDING_INLINE_P (r) = 0;
9054 DECL_SAVED_TREE (r) = NULL_TREE;
9055 DECL_STRUCT_FUNCTION (r) = NULL;
9057 /* We'll re-clone as appropriate in instantiate_template. */
9058 DECL_CLONED_FUNCTION (r) = NULL_TREE;
9060 /* If we aren't complaining now, return on error before we register
9061 the specialization so that we'll complain eventually. */
9062 if ((complain & tf_error) == 0
9063 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9064 && !grok_op_properties (r, /*complain=*/false))
9065 RETURN (error_mark_node);
9067 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
9068 this in the special friend case mentioned above where
9069 GEN_TMPL is NULL. */
9072 DECL_TEMPLATE_INFO (r)
9073 = build_template_info (gen_tmpl, argvec);
9074 SET_DECL_IMPLICIT_INSTANTIATION (r);
9075 register_specialization (r, gen_tmpl, argvec, false, hash);
9077 /* We're not supposed to instantiate default arguments
9078 until they are called, for a template. But, for a
9081 template <class T> void f ()
9082 { extern void g(int i = T()); }
9084 we should do the substitution when the template is
9085 instantiated. We handle the member function case in
9086 instantiate_class_template since the default arguments
9087 might refer to other members of the class. */
9089 && !PRIMARY_TEMPLATE_P (gen_tmpl)
9090 && !uses_template_parms (argvec))
9091 tsubst_default_arguments (r);
9094 DECL_TEMPLATE_INFO (r) = NULL_TREE;
9096 /* Copy the list of befriending classes. */
9097 for (friends = &DECL_BEFRIENDING_CLASSES (r);
9099 friends = &TREE_CHAIN (*friends))
9101 *friends = copy_node (*friends);
9102 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
9107 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
9109 maybe_retrofit_in_chrg (r);
9110 if (DECL_CONSTRUCTOR_P (r))
9111 grok_ctor_properties (ctx, r);
9112 /* If this is an instantiation of a member template, clone it.
9113 If it isn't, that'll be handled by
9114 clone_constructors_and_destructors. */
9115 if (PRIMARY_TEMPLATE_P (gen_tmpl))
9116 clone_function_decl (r, /*update_method_vec_p=*/0);
9118 else if ((complain & tf_error) != 0
9119 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
9120 && !grok_op_properties (r, /*complain=*/true))
9121 RETURN (error_mark_node);
9123 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
9124 SET_DECL_FRIEND_CONTEXT (r,
9125 tsubst (DECL_FRIEND_CONTEXT (t),
9126 args, complain, in_decl));
9128 /* Possibly limit visibility based on template args. */
9129 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9130 if (DECL_VISIBILITY_SPECIFIED (t))
9132 DECL_VISIBILITY_SPECIFIED (r) = 0;
9134 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9136 determine_visibility (r);
9137 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
9138 && !processing_template_decl)
9139 defaulted_late_check (r);
9141 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9142 args, complain, in_decl);
9148 tree type = NULL_TREE;
9150 tree expanded_types = NULL_TREE;
9151 tree prev_r = NULL_TREE;
9152 tree first_r = NULL_TREE;
9154 if (FUNCTION_PARAMETER_PACK_P (t))
9156 /* If there is a local specialization that isn't a
9157 parameter pack, it means that we're doing a "simple"
9158 substitution from inside tsubst_pack_expansion. Just
9159 return the local specialization (which will be a single
9161 tree spec = retrieve_local_specialization (t);
9163 && TREE_CODE (spec) == PARM_DECL
9164 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
9167 /* Expand the TYPE_PACK_EXPANSION that provides the types for
9168 the parameters in this function parameter pack. */
9169 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
9171 if (TREE_CODE (expanded_types) == TREE_VEC)
9173 len = TREE_VEC_LENGTH (expanded_types);
9175 /* Zero-length parameter packs are boring. Just substitute
9178 RETURN (tsubst (TREE_CHAIN (t), args, complain,
9183 /* All we did was update the type. Make a note of that. */
9184 type = expanded_types;
9185 expanded_types = NULL_TREE;
9189 /* Loop through all of the parameter's we'll build. When T is
9190 a function parameter pack, LEN is the number of expanded
9191 types in EXPANDED_TYPES; otherwise, LEN is 1. */
9193 for (i = 0; i < len; ++i)
9197 if (DECL_TEMPLATE_PARM_P (t))
9198 SET_DECL_TEMPLATE_PARM_P (r);
9200 /* An argument of a function parameter pack is not a parameter
9202 FUNCTION_PARAMETER_PACK_P (r) = false;
9205 /* We're on the Ith parameter of the function parameter
9208 /* Get the Ith type. */
9209 type = TREE_VEC_ELT (expanded_types, i);
9212 /* Rename the parameter to include the index. */
9214 make_ith_pack_parameter_name (DECL_NAME (r), i);
9217 /* We're dealing with a normal parameter. */
9218 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9220 type = type_decays_to (type);
9221 TREE_TYPE (r) = type;
9222 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9224 if (DECL_INITIAL (r))
9226 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
9227 DECL_INITIAL (r) = TREE_TYPE (r);
9229 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
9233 DECL_CONTEXT (r) = NULL_TREE;
9235 if (!DECL_TEMPLATE_PARM_P (r))
9236 DECL_ARG_TYPE (r) = type_passed_as (type);
9238 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9239 args, complain, in_decl);
9241 /* Keep track of the first new parameter we
9242 generate. That's what will be returned to the
9247 /* Build a proper chain of parameters when substituting
9248 into a function parameter pack. */
9250 TREE_CHAIN (prev_r) = r;
9254 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
9255 complain, TREE_CHAIN (t));
9257 /* FIRST_R contains the start of the chain we've built. */
9267 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9268 if (type == error_mark_node)
9269 RETURN (error_mark_node);
9270 TREE_TYPE (r) = type;
9271 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9273 /* DECL_INITIAL gives the number of bits in a bit-field. */
9275 = tsubst_expr (DECL_INITIAL (t), args,
9277 /*integral_constant_expression_p=*/true);
9278 /* We don't have to set DECL_CONTEXT here; it is set by
9279 finish_member_declaration. */
9280 TREE_CHAIN (r) = NULL_TREE;
9281 if (VOID_TYPE_P (type))
9282 error ("instantiation of %q+D as type %qT", r, type);
9284 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9285 args, complain, in_decl);
9290 /* We reach here only for member using decls. */
9291 if (DECL_DEPENDENT_P (t))
9293 r = do_class_using_decl
9294 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9295 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9297 r = error_mark_node;
9300 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9301 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9307 TREE_CHAIN (r) = NULL_TREE;
9314 tree argvec = NULL_TREE;
9315 tree gen_tmpl = NULL_TREE;
9317 tree tmpl = NULL_TREE;
9319 tree type = NULL_TREE;
9322 if (TREE_CODE (t) == TYPE_DECL
9323 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9325 /* If this is the canonical decl, we don't have to
9326 mess with instantiations, and often we can't (for
9327 typename, template type parms and such). Note that
9328 TYPE_NAME is not correct for the above test if
9329 we've copied the type for a typedef. */
9330 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9331 if (type == error_mark_node)
9332 RETURN (error_mark_node);
9333 r = TYPE_NAME (type);
9337 /* Check to see if we already have the specialization we
9340 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9342 /* T is a static data member or namespace-scope entity.
9343 We have to substitute into namespace-scope variables
9344 (even though such entities are never templates) because
9347 template <class T> void f() { extern T t; }
9349 where the entity referenced is not known until
9350 instantiation time. */
9352 ctx = DECL_CONTEXT (t);
9353 if (DECL_CLASS_SCOPE_P (t))
9355 ctx = tsubst_aggr_type (ctx, args,
9357 in_decl, /*entering_scope=*/1);
9358 /* If CTX is unchanged, then T is in fact the
9359 specialization we want. That situation occurs when
9360 referencing a static data member within in its own
9361 class. We can use pointer equality, rather than
9362 same_type_p, because DECL_CONTEXT is always
9364 if (ctx == DECL_CONTEXT (t))
9370 tmpl = DECL_TI_TEMPLATE (t);
9371 gen_tmpl = most_general_template (tmpl);
9372 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9373 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9374 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9379 /* A local variable. */
9381 /* Subsequent calls to pushdecl will fill this in. */
9383 spec = retrieve_local_specialization (t);
9385 /* If we already have the specialization we need, there is
9386 nothing more to do. */
9393 /* Create a new node for the specialization we need. */
9395 if (type == NULL_TREE)
9397 if (is_typedef_decl (t))
9398 type = DECL_ORIGINAL_TYPE (t);
9400 type = TREE_TYPE (t);
9401 type = tsubst (type, args, complain, in_decl);
9403 if (TREE_CODE (r) == VAR_DECL)
9405 /* Even if the original location is out of scope, the
9406 newly substituted one is not. */
9407 DECL_DEAD_FOR_LOCAL (r) = 0;
9408 DECL_INITIALIZED_P (r) = 0;
9409 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9410 if (type == error_mark_node)
9411 RETURN (error_mark_node);
9412 if (TREE_CODE (type) == FUNCTION_TYPE)
9414 /* It may seem that this case cannot occur, since:
9419 declares a function, not a variable. However:
9422 template <typename T> void g() { T t; }
9423 template void g<f>();
9425 is an attempt to declare a variable with function
9427 error ("variable %qD has function type",
9428 /* R is not yet sufficiently initialized, so we
9429 just use its name. */
9431 RETURN (error_mark_node);
9433 type = complete_type (type);
9434 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9435 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9436 type = check_var_type (DECL_NAME (r), type);
9438 if (DECL_HAS_VALUE_EXPR_P (t))
9440 tree ve = DECL_VALUE_EXPR (t);
9441 ve = tsubst_expr (ve, args, complain, in_decl,
9442 /*constant_expression_p=*/false);
9443 SET_DECL_VALUE_EXPR (r, ve);
9446 else if (DECL_SELF_REFERENCE_P (t))
9447 SET_DECL_SELF_REFERENCE_P (r);
9448 TREE_TYPE (r) = type;
9449 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9450 DECL_CONTEXT (r) = ctx;
9451 /* Clear out the mangled name and RTL for the instantiation. */
9452 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9453 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9454 SET_DECL_RTL (r, NULL_RTX);
9455 /* The initializer must not be expanded until it is required;
9457 DECL_INITIAL (r) = NULL_TREE;
9458 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9459 SET_DECL_RTL (r, NULL_RTX);
9460 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9461 if (TREE_CODE (r) == VAR_DECL)
9463 /* Possibly limit visibility based on template args. */
9464 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9465 if (DECL_VISIBILITY_SPECIFIED (t))
9467 DECL_VISIBILITY_SPECIFIED (r) = 0;
9469 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9471 determine_visibility (r);
9476 /* A static data member declaration is always marked
9477 external when it is declared in-class, even if an
9478 initializer is present. We mimic the non-template
9480 DECL_EXTERNAL (r) = 1;
9482 register_specialization (r, gen_tmpl, argvec, false, hash);
9483 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
9484 SET_DECL_IMPLICIT_INSTANTIATION (r);
9486 else if (cp_unevaluated_operand)
9488 /* We're substituting this var in a decltype outside of its
9489 scope, such as for a lambda return type. Don't add it to
9490 local_specializations, do perform auto deduction. */
9491 tree auto_node = type_uses_auto (type);
9493 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9494 /*constant_expression_p=*/false);
9496 if (auto_node && init && describable_type (init))
9498 type = do_auto_deduction (type, init, auto_node);
9499 TREE_TYPE (r) = type;
9503 register_local_specialization (r, t);
9505 TREE_CHAIN (r) = NULL_TREE;
9507 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9509 args, complain, in_decl);
9511 /* Preserve a typedef that names a type. */
9512 if (is_typedef_decl (r))
9514 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
9515 set_underlying_type (r);
9528 /* Restore the file and line information. */
9529 input_location = saved_loc;
9534 /* Substitute into the ARG_TYPES of a function type. */
9537 tsubst_arg_types (tree arg_types,
9539 tsubst_flags_t complain,
9542 tree remaining_arg_types;
9543 tree type = NULL_TREE;
9545 tree expanded_args = NULL_TREE;
9548 if (!arg_types || arg_types == void_list_node)
9551 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9552 args, complain, in_decl);
9553 if (remaining_arg_types == error_mark_node)
9554 return error_mark_node;
9556 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9558 /* For a pack expansion, perform substitution on the
9559 entire expression. Later on, we'll handle the arguments
9561 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9562 args, complain, in_decl);
9564 if (TREE_CODE (expanded_args) == TREE_VEC)
9565 /* So that we'll spin through the parameters, one by one. */
9566 i = TREE_VEC_LENGTH (expanded_args);
9569 /* We only partially substituted into the parameter
9570 pack. Our type is TYPE_PACK_EXPANSION. */
9571 type = expanded_args;
9572 expanded_args = NULL_TREE;
9580 type = TREE_VEC_ELT (expanded_args, i);
9582 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9584 if (type == error_mark_node)
9585 return error_mark_node;
9586 if (VOID_TYPE_P (type))
9588 if (complain & tf_error)
9590 error ("invalid parameter type %qT", type);
9592 error ("in declaration %q+D", in_decl);
9594 return error_mark_node;
9597 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9598 top-level qualifiers as required. */
9599 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9601 /* We do not substitute into default arguments here. The standard
9602 mandates that they be instantiated only when needed, which is
9603 done in build_over_call. */
9604 default_arg = TREE_PURPOSE (arg_types);
9606 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9608 /* We've instantiated a template before its default arguments
9609 have been parsed. This can happen for a nested template
9610 class, and is not an error unless we require the default
9611 argument in a call of this function. */
9612 remaining_arg_types =
9613 tree_cons (default_arg, type, remaining_arg_types);
9614 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9615 remaining_arg_types);
9618 remaining_arg_types =
9619 hash_tree_cons (default_arg, type, remaining_arg_types);
9622 return remaining_arg_types;
9625 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9626 *not* handle the exception-specification for FNTYPE, because the
9627 initial substitution of explicitly provided template parameters
9628 during argument deduction forbids substitution into the
9629 exception-specification:
9633 All references in the function type of the function template to the
9634 corresponding template parameters are replaced by the specified tem-
9635 plate argument values. If a substitution in a template parameter or
9636 in the function type of the function template results in an invalid
9637 type, type deduction fails. [Note: The equivalent substitution in
9638 exception specifications is done only when the function is instanti-
9639 ated, at which point a program is ill-formed if the substitution
9640 results in an invalid type.] */
9643 tsubst_function_type (tree t,
9645 tsubst_flags_t complain,
9652 /* The TYPE_CONTEXT is not used for function/method types. */
9653 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9655 /* Substitute the return type. */
9656 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9657 if (return_type == error_mark_node)
9658 return error_mark_node;
9659 /* The standard does not presently indicate that creation of a
9660 function type with an invalid return type is a deduction failure.
9661 However, that is clearly analogous to creating an array of "void"
9662 or a reference to a reference. This is core issue #486. */
9663 if (TREE_CODE (return_type) == ARRAY_TYPE
9664 || TREE_CODE (return_type) == FUNCTION_TYPE)
9666 if (complain & tf_error)
9668 if (TREE_CODE (return_type) == ARRAY_TYPE)
9669 error ("function returning an array");
9671 error ("function returning a function");
9673 return error_mark_node;
9676 /* Substitute the argument types. */
9677 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9679 if (arg_types == error_mark_node)
9680 return error_mark_node;
9682 /* Construct a new type node and return it. */
9683 if (TREE_CODE (t) == FUNCTION_TYPE)
9684 fntype = build_function_type (return_type, arg_types);
9687 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9688 if (! MAYBE_CLASS_TYPE_P (r))
9692 Type deduction may fail for any of the following
9695 -- Attempting to create "pointer to member of T" when T
9696 is not a class type. */
9697 if (complain & tf_error)
9698 error ("creating pointer to member function of non-class type %qT",
9700 return error_mark_node;
9703 fntype = build_method_type_directly (r, return_type,
9704 TREE_CHAIN (arg_types));
9706 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9707 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9712 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9713 ARGS into that specification, and return the substituted
9714 specification. If there is no specification, return NULL_TREE. */
9717 tsubst_exception_specification (tree fntype,
9719 tsubst_flags_t complain,
9725 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9726 new_specs = NULL_TREE;
9729 if (! TREE_VALUE (specs))
9736 tree expanded_specs = NULL_TREE;
9738 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9740 /* Expand the pack expansion type. */
9741 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9745 if (expanded_specs == error_mark_node)
9746 return error_mark_node;
9747 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9748 len = TREE_VEC_LENGTH (expanded_specs);
9751 /* We're substituting into a member template, so
9752 we got a TYPE_PACK_EXPANSION back. Add that
9753 expansion and move on. */
9754 gcc_assert (TREE_CODE (expanded_specs)
9755 == TYPE_PACK_EXPANSION);
9756 new_specs = add_exception_specifier (new_specs,
9759 specs = TREE_CHAIN (specs);
9764 for (i = 0; i < len; ++i)
9767 spec = TREE_VEC_ELT (expanded_specs, i);
9769 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9770 if (spec == error_mark_node)
9772 new_specs = add_exception_specifier (new_specs, spec,
9776 specs = TREE_CHAIN (specs);
9782 /* Take the tree structure T and replace template parameters used
9783 therein with the argument vector ARGS. IN_DECL is an associated
9784 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9785 Issue error and warning messages under control of COMPLAIN. Note
9786 that we must be relatively non-tolerant of extensions here, in
9787 order to preserve conformance; if we allow substitutions that
9788 should not be allowed, we may allow argument deductions that should
9789 not succeed, and therefore report ambiguous overload situations
9790 where there are none. In theory, we could allow the substitution,
9791 but indicate that it should have failed, and allow our caller to
9792 make sure that the right thing happens, but we don't try to do this
9795 This function is used for dealing with types, decls and the like;
9796 for expressions, use tsubst_expr or tsubst_copy. */
9799 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9803 if (t == NULL_TREE || t == error_mark_node
9804 || t == integer_type_node
9805 || t == void_type_node
9806 || t == char_type_node
9807 || t == unknown_type_node
9808 || TREE_CODE (t) == NAMESPACE_DECL)
9812 return tsubst_decl (t, args, complain);
9814 if (args == NULL_TREE)
9817 if (TREE_CODE (t) == IDENTIFIER_NODE)
9818 type = IDENTIFIER_TYPE_VALUE (t);
9820 type = TREE_TYPE (t);
9822 gcc_assert (type != unknown_type_node);
9824 /* Reuse typedefs. We need to do this to handle dependent attributes,
9825 such as attribute aligned. */
9828 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9830 tree decl = TYPE_NAME (t);
9832 if (DECL_CLASS_SCOPE_P (decl)
9833 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9834 && uses_template_parms (DECL_CONTEXT (decl)))
9836 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9837 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9838 r = retrieve_specialization (tmpl, gen_args, 0);
9840 else if (DECL_FUNCTION_SCOPE_P (decl)
9841 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9842 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9843 r = retrieve_local_specialization (decl);
9845 /* The typedef is from a non-template context. */
9851 r = cp_build_qualified_type_real
9852 (r, cp_type_quals (t) | cp_type_quals (r),
9853 complain | tf_ignore_bad_quals);
9856 /* Else we must be instantiating the typedef, so fall through. */
9860 && TREE_CODE (t) != TYPENAME_TYPE
9861 && TREE_CODE (t) != IDENTIFIER_NODE
9862 && TREE_CODE (t) != FUNCTION_TYPE
9863 && TREE_CODE (t) != METHOD_TYPE)
9864 type = tsubst (type, args, complain, in_decl);
9865 if (type == error_mark_node)
9866 return error_mark_node;
9868 switch (TREE_CODE (t))
9873 return tsubst_aggr_type (t, args, complain, in_decl,
9874 /*entering_scope=*/0);
9877 case IDENTIFIER_NODE:
9889 if (t == integer_type_node)
9892 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9893 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9897 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9899 max = tsubst_expr (omax, args, complain, in_decl,
9900 /*integral_constant_expression_p=*/false);
9902 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9904 if (TREE_CODE (max) == NOP_EXPR
9905 && TREE_SIDE_EFFECTS (omax)
9906 && !TREE_TYPE (max))
9907 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9909 max = fold_decl_constant_value (max);
9911 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9912 with TREE_SIDE_EFFECTS that indicates this is not an integral
9913 constant expression. */
9914 if (processing_template_decl
9915 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9917 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9918 TREE_SIDE_EFFECTS (max) = 1;
9921 if (TREE_CODE (max) != INTEGER_CST
9922 && !at_function_scope_p ()
9923 && !TREE_SIDE_EFFECTS (max)
9924 && !value_dependent_expression_p (max))
9926 if (complain & tf_error)
9927 error ("array bound is not an integer constant");
9928 return error_mark_node;
9933 Type deduction may fail for any of the following
9936 Attempting to create an array with a size that is
9937 zero or negative. */
9938 if (integer_zerop (max) && !(complain & tf_error))
9939 /* We must fail if performing argument deduction (as
9940 indicated by the state of complain), so that
9941 another substitution can be found. */
9942 return error_mark_node;
9943 else if (TREE_CODE (max) == INTEGER_CST
9944 && INT_CST_LT (max, integer_zero_node))
9946 if (complain & tf_error)
9947 error ("creating array with negative size (%qE)", max);
9949 return error_mark_node;
9952 return compute_array_index_type (NULL_TREE, max);
9955 case TEMPLATE_TYPE_PARM:
9956 case TEMPLATE_TEMPLATE_PARM:
9957 case BOUND_TEMPLATE_TEMPLATE_PARM:
9958 case TEMPLATE_PARM_INDEX:
9963 tree arg = NULL_TREE;
9967 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9968 template_parm_level_and_index (t, &level, &idx);
9970 levels = TMPL_ARGS_DEPTH (args);
9971 if (level <= levels)
9973 arg = TMPL_ARG (args, level, idx);
9975 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9976 /* See through ARGUMENT_PACK_SELECT arguments. */
9977 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9980 if (arg == error_mark_node)
9981 return error_mark_node;
9982 else if (arg != NULL_TREE)
9984 if (ARGUMENT_PACK_P (arg))
9985 /* If ARG is an argument pack, we don't actually want to
9986 perform a substitution here, because substitutions
9987 for argument packs are only done
9988 element-by-element. We can get to this point when
9989 substituting the type of a non-type template
9990 parameter pack, when that type actually contains
9991 template parameter packs from an outer template, e.g.,
9993 template<typename... Types> struct A {
9994 template<Types... Values> struct B { };
9998 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
10001 gcc_assert (TYPE_P (arg));
10003 /* cv-quals from the template are discarded when
10004 substituting in a function or reference type. */
10005 if (TREE_CODE (arg) == FUNCTION_TYPE
10006 || TREE_CODE (arg) == METHOD_TYPE
10007 || TREE_CODE (arg) == REFERENCE_TYPE)
10008 quals = cp_type_quals (arg);
10010 quals = cp_type_quals (arg) | cp_type_quals (t);
10012 return cp_build_qualified_type_real
10013 (arg, quals, complain | tf_ignore_bad_quals);
10015 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
10017 /* We are processing a type constructed from a
10018 template template parameter. */
10019 tree argvec = tsubst (TYPE_TI_ARGS (t),
10020 args, complain, in_decl);
10021 if (argvec == error_mark_node)
10022 return error_mark_node;
10024 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
10025 are resolving nested-types in the signature of a
10026 member function templates. Otherwise ARG is a
10027 TEMPLATE_DECL and is the real template to be
10029 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
10030 arg = TYPE_NAME (arg);
10032 r = lookup_template_class (arg,
10034 DECL_CONTEXT (arg),
10035 /*entering_scope=*/0,
10037 return cp_build_qualified_type_real
10038 (r, TYPE_QUALS (t), complain);
10041 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
10046 /* This can happen during the attempted tsubst'ing in
10047 unify. This means that we don't yet have any information
10048 about the template parameter in question. */
10051 /* If we get here, we must have been looking at a parm for a
10052 more deeply nested template. Make a new version of this
10053 template parameter, but with a lower level. */
10054 switch (TREE_CODE (t))
10056 case TEMPLATE_TYPE_PARM:
10057 case TEMPLATE_TEMPLATE_PARM:
10058 case BOUND_TEMPLATE_TEMPLATE_PARM:
10059 if (cp_type_quals (t))
10061 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
10062 r = cp_build_qualified_type_real
10063 (r, cp_type_quals (t),
10064 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
10065 ? tf_ignore_bad_quals : 0));
10070 TEMPLATE_TYPE_PARM_INDEX (r)
10071 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
10072 r, levels, args, complain);
10073 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
10074 TYPE_MAIN_VARIANT (r) = r;
10075 TYPE_POINTER_TO (r) = NULL_TREE;
10076 TYPE_REFERENCE_TO (r) = NULL_TREE;
10078 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
10079 /* We have reduced the level of the template
10080 template parameter, but not the levels of its
10081 template parameters, so canonical_type_parameter
10082 will not be able to find the canonical template
10083 template parameter for this level. Thus, we
10084 require structural equality checking to compare
10085 TEMPLATE_TEMPLATE_PARMs. */
10086 SET_TYPE_STRUCTURAL_EQUALITY (r);
10087 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
10088 SET_TYPE_STRUCTURAL_EQUALITY (r);
10090 TYPE_CANONICAL (r) = canonical_type_parameter (r);
10092 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
10094 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
10095 complain, in_decl);
10096 if (argvec == error_mark_node)
10097 return error_mark_node;
10099 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
10100 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
10105 case TEMPLATE_PARM_INDEX:
10106 r = reduce_template_parm_level (t, type, levels, args, complain);
10110 gcc_unreachable ();
10118 tree purpose, value, chain;
10120 if (t == void_list_node)
10123 purpose = TREE_PURPOSE (t);
10126 purpose = tsubst (purpose, args, complain, in_decl);
10127 if (purpose == error_mark_node)
10128 return error_mark_node;
10130 value = TREE_VALUE (t);
10133 value = tsubst (value, args, complain, in_decl);
10134 if (value == error_mark_node)
10135 return error_mark_node;
10137 chain = TREE_CHAIN (t);
10138 if (chain && chain != void_type_node)
10140 chain = tsubst (chain, args, complain, in_decl);
10141 if (chain == error_mark_node)
10142 return error_mark_node;
10144 if (purpose == TREE_PURPOSE (t)
10145 && value == TREE_VALUE (t)
10146 && chain == TREE_CHAIN (t))
10148 return hash_tree_cons (purpose, value, chain);
10152 /* We should never be tsubsting a binfo. */
10153 gcc_unreachable ();
10156 /* A vector of template arguments. */
10157 gcc_assert (!type);
10158 return tsubst_template_args (t, args, complain, in_decl);
10161 case REFERENCE_TYPE:
10163 enum tree_code code;
10165 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
10168 code = TREE_CODE (t);
10173 Type deduction may fail for any of the following
10176 -- Attempting to create a pointer to reference type.
10177 -- Attempting to create a reference to a reference type or
10178 a reference to void.
10180 Core issue 106 says that creating a reference to a reference
10181 during instantiation is no longer a cause for failure. We
10182 only enforce this check in strict C++98 mode. */
10183 if ((TREE_CODE (type) == REFERENCE_TYPE
10184 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
10185 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
10187 static location_t last_loc;
10189 /* We keep track of the last time we issued this error
10190 message to avoid spewing a ton of messages during a
10191 single bad template instantiation. */
10192 if (complain & tf_error
10193 && last_loc != input_location)
10195 if (TREE_CODE (type) == VOID_TYPE)
10196 error ("forming reference to void");
10197 else if (code == POINTER_TYPE)
10198 error ("forming pointer to reference type %qT", type);
10200 error ("forming reference to reference type %qT", type);
10201 last_loc = input_location;
10204 return error_mark_node;
10206 else if (code == POINTER_TYPE)
10208 r = build_pointer_type (type);
10209 if (TREE_CODE (type) == METHOD_TYPE)
10210 r = build_ptrmemfunc_type (r);
10212 else if (TREE_CODE (type) == REFERENCE_TYPE)
10213 /* In C++0x, during template argument substitution, when there is an
10214 attempt to create a reference to a reference type, reference
10215 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
10217 "If a template-argument for a template-parameter T names a type
10218 that is a reference to a type A, an attempt to create the type
10219 'lvalue reference to cv T' creates the type 'lvalue reference to
10220 A,' while an attempt to create the type type rvalue reference to
10221 cv T' creates the type T"
10223 r = cp_build_reference_type
10225 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
10227 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
10228 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
10230 if (r != error_mark_node)
10231 /* Will this ever be needed for TYPE_..._TO values? */
10238 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
10239 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
10243 Type deduction may fail for any of the following
10246 -- Attempting to create "pointer to member of T" when T
10247 is not a class type. */
10248 if (complain & tf_error)
10249 error ("creating pointer to member of non-class type %qT", r);
10250 return error_mark_node;
10252 if (TREE_CODE (type) == REFERENCE_TYPE)
10254 if (complain & tf_error)
10255 error ("creating pointer to member reference type %qT", type);
10256 return error_mark_node;
10258 if (TREE_CODE (type) == VOID_TYPE)
10260 if (complain & tf_error)
10261 error ("creating pointer to member of type void");
10262 return error_mark_node;
10264 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10265 if (TREE_CODE (type) == FUNCTION_TYPE)
10267 /* The type of the implicit object parameter gets its
10268 cv-qualifiers from the FUNCTION_TYPE. */
10270 tree method_type = build_memfn_type (type, r, cp_type_quals (type));
10271 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10272 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10276 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10280 case FUNCTION_TYPE:
10285 fntype = tsubst_function_type (t, args, complain, in_decl);
10286 if (fntype == error_mark_node)
10287 return error_mark_node;
10289 /* Substitute the exception specification. */
10290 specs = tsubst_exception_specification (t, args, complain,
10292 if (specs == error_mark_node)
10293 return error_mark_node;
10295 fntype = build_exception_variant (fntype, specs);
10300 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10301 if (domain == error_mark_node)
10302 return error_mark_node;
10304 /* As an optimization, we avoid regenerating the array type if
10305 it will obviously be the same as T. */
10306 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10309 /* These checks should match the ones in grokdeclarator.
10313 The deduction may fail for any of the following reasons:
10315 -- Attempting to create an array with an element type that
10316 is void, a function type, or a reference type, or [DR337]
10317 an abstract class type. */
10318 if (TREE_CODE (type) == VOID_TYPE
10319 || TREE_CODE (type) == FUNCTION_TYPE
10320 || TREE_CODE (type) == REFERENCE_TYPE)
10322 if (complain & tf_error)
10323 error ("creating array of %qT", type);
10324 return error_mark_node;
10326 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10328 if (complain & tf_error)
10329 error ("creating array of %qT, which is an abstract class type",
10331 return error_mark_node;
10334 r = build_cplus_array_type (type, domain);
10336 if (TYPE_USER_ALIGN (t))
10338 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10339 TYPE_USER_ALIGN (r) = 1;
10348 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10349 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10351 if (e1 == error_mark_node || e2 == error_mark_node)
10352 return error_mark_node;
10354 return fold_build2_loc (input_location,
10355 TREE_CODE (t), TREE_TYPE (t), e1, e2);
10361 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10362 if (e == error_mark_node)
10363 return error_mark_node;
10365 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
10368 case TYPENAME_TYPE:
10370 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10371 in_decl, /*entering_scope=*/1);
10372 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10373 complain, in_decl);
10375 if (ctx == error_mark_node || f == error_mark_node)
10376 return error_mark_node;
10378 if (!MAYBE_CLASS_TYPE_P (ctx))
10380 if (complain & tf_error)
10381 error ("%qT is not a class, struct, or union type", ctx);
10382 return error_mark_node;
10384 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10386 /* Normally, make_typename_type does not require that the CTX
10387 have complete type in order to allow things like:
10389 template <class T> struct S { typename S<T>::X Y; };
10391 But, such constructs have already been resolved by this
10392 point, so here CTX really should have complete type, unless
10393 it's a partial instantiation. */
10394 if (!(complain & tf_no_class_instantiations))
10395 ctx = complete_type (ctx);
10396 if (!COMPLETE_TYPE_P (ctx))
10398 if (complain & tf_error)
10399 cxx_incomplete_type_error (NULL_TREE, ctx);
10400 return error_mark_node;
10404 f = make_typename_type (ctx, f, typename_type,
10405 (complain & tf_error) | tf_keep_type_decl);
10406 if (f == error_mark_node)
10408 if (TREE_CODE (f) == TYPE_DECL)
10410 complain |= tf_ignore_bad_quals;
10414 if (TREE_CODE (f) != TYPENAME_TYPE)
10416 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10417 error ("%qT resolves to %qT, which is not an enumeration type",
10419 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10420 error ("%qT resolves to %qT, which is is not a class type",
10424 return cp_build_qualified_type_real
10425 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10428 case UNBOUND_CLASS_TEMPLATE:
10430 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10431 in_decl, /*entering_scope=*/1);
10432 tree name = TYPE_IDENTIFIER (t);
10433 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10435 if (ctx == error_mark_node || name == error_mark_node)
10436 return error_mark_node;
10439 parm_list = tsubst_template_parms (parm_list, args, complain);
10440 return make_unbound_class_template (ctx, name, parm_list, complain);
10446 gcc_unreachable ();
10450 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10451 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10452 /*integral_constant_expression_p=*/false);
10453 if (e1 == error_mark_node || e2 == error_mark_node)
10454 return error_mark_node;
10456 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10461 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10462 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10463 if (e1 == error_mark_node || e2 == error_mark_node)
10464 return error_mark_node;
10466 return build_qualified_name (/*type=*/NULL_TREE,
10467 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10474 ++cp_unevaluated_operand;
10475 ++c_inhibit_evaluation_warnings;
10477 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10479 /*integral_constant_expression_p=*/false);
10481 --cp_unevaluated_operand;
10482 --c_inhibit_evaluation_warnings;
10484 type = finish_typeof (type);
10485 return cp_build_qualified_type_real (type,
10487 | cp_type_quals (type),
10491 case DECLTYPE_TYPE:
10495 ++cp_unevaluated_operand;
10496 ++c_inhibit_evaluation_warnings;
10498 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10500 /*integral_constant_expression_p=*/false);
10502 --cp_unevaluated_operand;
10503 --c_inhibit_evaluation_warnings;
10505 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10506 type = lambda_capture_field_type (type);
10507 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10508 type = lambda_return_type (type);
10510 type = finish_decltype_type
10511 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10512 return cp_build_qualified_type_real (type,
10514 | cp_type_quals (type),
10518 case TYPE_ARGUMENT_PACK:
10519 case NONTYPE_ARGUMENT_PACK:
10521 tree r = TYPE_P (t)
10522 ? cxx_make_type (TREE_CODE (t))
10523 : make_node (TREE_CODE (t));
10525 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10529 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10531 /* For template nontype argument packs, also substitute into
10533 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10534 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10541 sorry ("use of %qs in template",
10542 tree_code_name [(int) TREE_CODE (t)]);
10543 return error_mark_node;
10547 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10548 type of the expression on the left-hand side of the "." or "->"
10552 tsubst_baselink (tree baselink, tree object_type,
10553 tree args, tsubst_flags_t complain, tree in_decl)
10556 tree qualifying_scope;
10559 tree template_args = 0;
10560 bool template_id_p = false;
10562 /* A baselink indicates a function from a base class. Both the
10563 BASELINK_ACCESS_BINFO and the base class referenced may
10564 indicate bases of the template class, rather than the
10565 instantiated class. In addition, lookups that were not
10566 ambiguous before may be ambiguous now. Therefore, we perform
10567 the lookup again. */
10568 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10569 qualifying_scope = tsubst (qualifying_scope, args,
10570 complain, in_decl);
10571 fns = BASELINK_FUNCTIONS (baselink);
10572 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
10573 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10575 template_id_p = true;
10576 template_args = TREE_OPERAND (fns, 1);
10577 fns = TREE_OPERAND (fns, 0);
10579 template_args = tsubst_template_args (template_args, args,
10580 complain, in_decl);
10582 name = DECL_NAME (get_first_fn (fns));
10583 if (IDENTIFIER_TYPENAME_P (name))
10584 name = mangle_conv_op_name_for_type (optype);
10585 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10587 /* If lookup found a single function, mark it as used at this
10588 point. (If it lookup found multiple functions the one selected
10589 later by overload resolution will be marked as used at that
10591 if (BASELINK_P (baselink))
10592 fns = BASELINK_FUNCTIONS (baselink);
10593 if (!template_id_p && !really_overloaded_fn (fns))
10594 mark_used (OVL_CURRENT (fns));
10596 /* Add back the template arguments, if present. */
10597 if (BASELINK_P (baselink) && template_id_p)
10598 BASELINK_FUNCTIONS (baselink)
10599 = build_nt (TEMPLATE_ID_EXPR,
10600 BASELINK_FUNCTIONS (baselink),
10602 /* Update the conversion operator type. */
10603 BASELINK_OPTYPE (baselink) = optype;
10606 object_type = current_class_type;
10607 return adjust_result_of_qualified_name_lookup (baselink,
10612 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10613 true if the qualified-id will be a postfix-expression in-and-of
10614 itself; false if more of the postfix-expression follows the
10615 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10619 tsubst_qualified_id (tree qualified_id, tree args,
10620 tsubst_flags_t complain, tree in_decl,
10621 bool done, bool address_p)
10627 tree template_args;
10629 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10631 /* Figure out what name to look up. */
10632 name = TREE_OPERAND (qualified_id, 1);
10633 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10635 is_template = true;
10636 template_args = TREE_OPERAND (name, 1);
10638 template_args = tsubst_template_args (template_args, args,
10639 complain, in_decl);
10640 name = TREE_OPERAND (name, 0);
10644 is_template = false;
10645 template_args = NULL_TREE;
10648 /* Substitute into the qualifying scope. When there are no ARGS, we
10649 are just trying to simplify a non-dependent expression. In that
10650 case the qualifying scope may be dependent, and, in any case,
10651 substituting will not help. */
10652 scope = TREE_OPERAND (qualified_id, 0);
10655 scope = tsubst (scope, args, complain, in_decl);
10656 expr = tsubst_copy (name, args, complain, in_decl);
10661 if (dependent_scope_p (scope))
10662 return build_qualified_name (NULL_TREE, scope, expr,
10663 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10665 if (!BASELINK_P (name) && !DECL_P (expr))
10667 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10669 /* A BIT_NOT_EXPR is used to represent a destructor. */
10670 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10672 error ("qualifying type %qT does not match destructor name ~%qT",
10673 scope, TREE_OPERAND (expr, 0));
10674 expr = error_mark_node;
10677 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10678 /*is_type_p=*/0, false);
10681 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10682 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10683 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10685 if (complain & tf_error)
10687 error ("dependent-name %qE is parsed as a non-type, but "
10688 "instantiation yields a type", qualified_id);
10689 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10691 return error_mark_node;
10697 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10699 /* Remember that there was a reference to this entity. */
10703 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10705 if (complain & tf_error)
10706 qualified_name_lookup_error (scope,
10707 TREE_OPERAND (qualified_id, 1),
10708 expr, input_location);
10709 return error_mark_node;
10713 expr = lookup_template_function (expr, template_args);
10715 if (expr == error_mark_node && complain & tf_error)
10716 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10717 expr, input_location);
10718 else if (TYPE_P (scope))
10720 expr = (adjust_result_of_qualified_name_lookup
10721 (expr, scope, current_class_type));
10722 expr = (finish_qualified_id_expr
10723 (scope, expr, done, address_p,
10724 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10725 /*template_arg_p=*/false));
10728 /* Expressions do not generally have reference type. */
10729 if (TREE_CODE (expr) != SCOPE_REF
10730 /* However, if we're about to form a pointer-to-member, we just
10731 want the referenced member referenced. */
10732 && TREE_CODE (expr) != OFFSET_REF)
10733 expr = convert_from_reference (expr);
10738 /* Like tsubst, but deals with expressions. This function just replaces
10739 template parms; to finish processing the resultant expression, use
10743 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10745 enum tree_code code;
10748 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10751 code = TREE_CODE (t);
10756 r = retrieve_local_specialization (t);
10761 /* This can happen for a parameter name used later in a function
10762 declaration (such as in a late-specified return type). Just
10763 make a dummy decl, since it's only used for its type. */
10764 gcc_assert (cp_unevaluated_operand != 0);
10765 /* We copy T because want to tsubst the PARM_DECL only,
10766 not the following PARM_DECLs that are chained to T. */
10768 r = tsubst_decl (c, args, complain);
10769 /* Give it the template pattern as its context; its true context
10770 hasn't been instantiated yet and this is good enough for
10772 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10775 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10776 r = ARGUMENT_PACK_SELECT_ARG (r);
10785 if (DECL_TEMPLATE_PARM_P (t))
10786 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10787 /* There is no need to substitute into namespace-scope
10789 if (DECL_NAMESPACE_SCOPE_P (t))
10791 /* If ARGS is NULL, then T is known to be non-dependent. */
10792 if (args == NULL_TREE)
10793 return integral_constant_value (t);
10795 /* Unfortunately, we cannot just call lookup_name here.
10798 template <int I> int f() {
10800 struct S { void g() { E e = a; } };
10803 When we instantiate f<7>::S::g(), say, lookup_name is not
10804 clever enough to find f<7>::a. */
10806 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10807 /*entering_scope=*/0);
10809 for (v = TYPE_VALUES (enum_type);
10811 v = TREE_CHAIN (v))
10812 if (TREE_PURPOSE (v) == DECL_NAME (t))
10813 return TREE_VALUE (v);
10815 /* We didn't find the name. That should never happen; if
10816 name-lookup found it during preliminary parsing, we
10817 should find it again here during instantiation. */
10818 gcc_unreachable ();
10823 if (DECL_CONTEXT (t))
10827 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10828 /*entering_scope=*/1);
10829 if (ctx != DECL_CONTEXT (t))
10831 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10834 if (complain & tf_error)
10835 error ("using invalid field %qD", t);
10836 return error_mark_node;
10845 case FUNCTION_DECL:
10846 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10847 || local_variable_p (t))
10848 t = tsubst (t, args, complain, in_decl);
10853 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10855 case TEMPLATE_DECL:
10856 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10857 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10858 args, complain, in_decl);
10859 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10860 return tsubst (t, args, complain, in_decl);
10861 else if (DECL_CLASS_SCOPE_P (t)
10862 && uses_template_parms (DECL_CONTEXT (t)))
10864 /* Template template argument like the following example need
10867 template <template <class> class TT> struct C {};
10868 template <class T> struct D {
10869 template <class U> struct E {};
10874 We are processing the template argument `E' in #1 for
10875 the template instantiation #2. Originally, `E' is a
10876 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10877 have to substitute this with one having context `D<int>'. */
10879 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10880 return lookup_field (context, DECL_NAME(t), 0, false);
10883 /* Ordinary template template argument. */
10887 case REINTERPRET_CAST_EXPR:
10888 case CONST_CAST_EXPR:
10889 case STATIC_CAST_EXPR:
10890 case DYNAMIC_CAST_EXPR:
10893 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10894 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10897 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10899 /* We only want to compute the number of arguments. */
10900 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10901 complain, in_decl);
10904 if (TREE_CODE (expanded) == TREE_VEC)
10905 len = TREE_VEC_LENGTH (expanded);
10907 if (expanded == error_mark_node)
10908 return error_mark_node;
10909 else if (PACK_EXPANSION_P (expanded)
10910 || (TREE_CODE (expanded) == TREE_VEC
10912 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10914 if (TREE_CODE (expanded) == TREE_VEC)
10915 expanded = TREE_VEC_ELT (expanded, len - 1);
10917 if (TYPE_P (expanded))
10918 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10919 complain & tf_error);
10921 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10922 complain & tf_error);
10925 return build_int_cst (size_type_node, len);
10931 case TRUTH_NOT_EXPR:
10934 case UNARY_PLUS_EXPR: /* Unary + */
10939 case REALPART_EXPR:
10940 case IMAGPART_EXPR:
10942 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10943 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10945 case COMPONENT_REF:
10950 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10951 name = TREE_OPERAND (t, 1);
10952 if (TREE_CODE (name) == BIT_NOT_EXPR)
10954 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10955 complain, in_decl);
10956 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10958 else if (TREE_CODE (name) == SCOPE_REF
10959 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10961 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10962 complain, in_decl);
10963 name = TREE_OPERAND (name, 1);
10964 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10965 complain, in_decl);
10966 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10967 name = build_qualified_name (/*type=*/NULL_TREE,
10969 /*template_p=*/false);
10971 else if (TREE_CODE (name) == BASELINK)
10972 name = tsubst_baselink (name,
10973 non_reference (TREE_TYPE (object)),
10977 name = tsubst_copy (name, args, complain, in_decl);
10978 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10984 case TRUNC_DIV_EXPR:
10985 case CEIL_DIV_EXPR:
10986 case FLOOR_DIV_EXPR:
10987 case ROUND_DIV_EXPR:
10988 case EXACT_DIV_EXPR:
10992 case TRUNC_MOD_EXPR:
10993 case FLOOR_MOD_EXPR:
10994 case TRUTH_ANDIF_EXPR:
10995 case TRUTH_ORIF_EXPR:
10996 case TRUTH_AND_EXPR:
10997 case TRUTH_OR_EXPR:
11010 case COMPOUND_EXPR:
11013 case PREDECREMENT_EXPR:
11014 case PREINCREMENT_EXPR:
11015 case POSTDECREMENT_EXPR:
11016 case POSTINCREMENT_EXPR:
11018 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11019 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11022 return build_qualified_name (/*type=*/NULL_TREE,
11023 tsubst_copy (TREE_OPERAND (t, 0),
11024 args, complain, in_decl),
11025 tsubst_copy (TREE_OPERAND (t, 1),
11026 args, complain, in_decl),
11027 QUALIFIED_NAME_IS_TEMPLATE (t));
11032 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11033 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11034 NULL_TREE, NULL_TREE);
11038 int n = VL_EXP_OPERAND_LENGTH (t);
11039 tree result = build_vl_exp (CALL_EXPR, n);
11041 for (i = 0; i < n; i++)
11042 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
11043 complain, in_decl);
11049 case PSEUDO_DTOR_EXPR:
11052 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11053 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11054 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11055 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11062 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11063 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
11064 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
11065 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
11072 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
11073 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
11074 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
11075 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
11079 case TEMPLATE_ID_EXPR:
11081 /* Substituted template arguments */
11082 tree fn = TREE_OPERAND (t, 0);
11083 tree targs = TREE_OPERAND (t, 1);
11085 fn = tsubst_copy (fn, args, complain, in_decl);
11087 targs = tsubst_template_args (targs, args, complain, in_decl);
11089 return lookup_template_function (fn, targs);
11094 tree purpose, value, chain;
11096 if (t == void_list_node)
11099 purpose = TREE_PURPOSE (t);
11101 purpose = tsubst_copy (purpose, args, complain, in_decl);
11102 value = TREE_VALUE (t);
11104 value = tsubst_copy (value, args, complain, in_decl);
11105 chain = TREE_CHAIN (t);
11106 if (chain && chain != void_type_node)
11107 chain = tsubst_copy (chain, args, complain, in_decl);
11108 if (purpose == TREE_PURPOSE (t)
11109 && value == TREE_VALUE (t)
11110 && chain == TREE_CHAIN (t))
11112 return tree_cons (purpose, value, chain);
11117 case ENUMERAL_TYPE:
11119 case TEMPLATE_TYPE_PARM:
11120 case TEMPLATE_TEMPLATE_PARM:
11121 case BOUND_TEMPLATE_TEMPLATE_PARM:
11122 case TEMPLATE_PARM_INDEX:
11124 case REFERENCE_TYPE:
11126 case FUNCTION_TYPE:
11129 case TYPENAME_TYPE:
11130 case UNBOUND_CLASS_TEMPLATE:
11132 case DECLTYPE_TYPE:
11134 return tsubst (t, args, complain, in_decl);
11136 case IDENTIFIER_NODE:
11137 if (IDENTIFIER_TYPENAME_P (t))
11139 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11140 return mangle_conv_op_name_for_type (new_type);
11146 /* This is handled by tsubst_copy_and_build. */
11147 gcc_unreachable ();
11150 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
11152 tsubst (TREE_TYPE (t), args, complain, in_decl));
11154 case CLEANUP_POINT_EXPR:
11155 /* We shouldn't have built any of these during initial template
11156 generation. Instead, they should be built during instantiation
11157 in response to the saved STMT_IS_FULL_EXPR_P setting. */
11158 gcc_unreachable ();
11161 mark_used (TREE_OPERAND (t, 1));
11164 case EXPR_PACK_EXPANSION:
11165 error ("invalid use of pack expansion expression");
11166 return error_mark_node;
11168 case NONTYPE_ARGUMENT_PACK:
11169 error ("use %<...%> to expand argument pack");
11170 return error_mark_node;
11177 /* Like tsubst_copy, but specifically for OpenMP clauses. */
11180 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
11183 tree new_clauses = NULL, nc, oc;
11185 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
11187 nc = copy_node (oc);
11188 OMP_CLAUSE_CHAIN (nc) = new_clauses;
11191 switch (OMP_CLAUSE_CODE (nc))
11193 case OMP_CLAUSE_LASTPRIVATE:
11194 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
11196 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
11197 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
11198 in_decl, /*integral_constant_expression_p=*/false);
11199 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
11200 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
11203 case OMP_CLAUSE_PRIVATE:
11204 case OMP_CLAUSE_SHARED:
11205 case OMP_CLAUSE_FIRSTPRIVATE:
11206 case OMP_CLAUSE_REDUCTION:
11207 case OMP_CLAUSE_COPYIN:
11208 case OMP_CLAUSE_COPYPRIVATE:
11209 case OMP_CLAUSE_IF:
11210 case OMP_CLAUSE_NUM_THREADS:
11211 case OMP_CLAUSE_SCHEDULE:
11212 case OMP_CLAUSE_COLLAPSE:
11213 OMP_CLAUSE_OPERAND (nc, 0)
11214 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
11215 in_decl, /*integral_constant_expression_p=*/false);
11217 case OMP_CLAUSE_NOWAIT:
11218 case OMP_CLAUSE_ORDERED:
11219 case OMP_CLAUSE_DEFAULT:
11220 case OMP_CLAUSE_UNTIED:
11223 gcc_unreachable ();
11227 return finish_omp_clauses (nreverse (new_clauses));
11230 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
11233 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
11236 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
11238 tree purpose, value, chain;
11243 if (TREE_CODE (t) != TREE_LIST)
11244 return tsubst_copy_and_build (t, args, complain, in_decl,
11245 /*function_p=*/false,
11246 /*integral_constant_expression_p=*/false);
11248 if (t == void_list_node)
11251 purpose = TREE_PURPOSE (t);
11253 purpose = RECUR (purpose);
11254 value = TREE_VALUE (t);
11255 if (value && TREE_CODE (value) != LABEL_DECL)
11256 value = RECUR (value);
11257 chain = TREE_CHAIN (t);
11258 if (chain && chain != void_type_node)
11259 chain = RECUR (chain);
11260 return tree_cons (purpose, value, chain);
11264 /* Substitute one OMP_FOR iterator. */
11267 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11268 tree condv, tree incrv, tree *clauses,
11269 tree args, tsubst_flags_t complain, tree in_decl,
11270 bool integral_constant_expression_p)
11272 #define RECUR(NODE) \
11273 tsubst_expr ((NODE), args, complain, in_decl, \
11274 integral_constant_expression_p)
11275 tree decl, init, cond, incr, auto_node;
11277 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11278 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11279 decl = RECUR (TREE_OPERAND (init, 0));
11280 init = TREE_OPERAND (init, 1);
11281 auto_node = type_uses_auto (TREE_TYPE (decl));
11282 if (auto_node && init)
11284 tree init_expr = init;
11285 if (TREE_CODE (init_expr) == DECL_EXPR)
11286 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11287 init_expr = RECUR (init_expr);
11289 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11291 gcc_assert (!type_dependent_expression_p (decl));
11293 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11295 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11296 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11297 if (TREE_CODE (incr) == MODIFY_EXPR)
11298 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11299 RECUR (TREE_OPERAND (incr, 1)),
11302 incr = RECUR (incr);
11303 TREE_VEC_ELT (declv, i) = decl;
11304 TREE_VEC_ELT (initv, i) = init;
11305 TREE_VEC_ELT (condv, i) = cond;
11306 TREE_VEC_ELT (incrv, i) = incr;
11310 if (init && TREE_CODE (init) != DECL_EXPR)
11313 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11315 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11316 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11317 && OMP_CLAUSE_DECL (c) == decl)
11319 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11320 && OMP_CLAUSE_DECL (c) == decl)
11321 error ("iteration variable %qD should not be firstprivate", decl);
11322 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11323 && OMP_CLAUSE_DECL (c) == decl)
11324 error ("iteration variable %qD should not be reduction", decl);
11328 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11329 OMP_CLAUSE_DECL (c) = decl;
11330 c = finish_omp_clauses (c);
11333 OMP_CLAUSE_CHAIN (c) = *clauses;
11338 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11339 if (COMPARISON_CLASS_P (cond))
11340 cond = build2 (TREE_CODE (cond), boolean_type_node,
11341 RECUR (TREE_OPERAND (cond, 0)),
11342 RECUR (TREE_OPERAND (cond, 1)));
11344 cond = RECUR (cond);
11345 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11346 switch (TREE_CODE (incr))
11348 case PREINCREMENT_EXPR:
11349 case PREDECREMENT_EXPR:
11350 case POSTINCREMENT_EXPR:
11351 case POSTDECREMENT_EXPR:
11352 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11353 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11356 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11357 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11359 tree rhs = TREE_OPERAND (incr, 1);
11360 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11361 RECUR (TREE_OPERAND (incr, 0)),
11362 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11363 RECUR (TREE_OPERAND (rhs, 0)),
11364 RECUR (TREE_OPERAND (rhs, 1))));
11367 incr = RECUR (incr);
11370 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11371 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11373 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11374 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11375 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11376 TREE_TYPE (decl), lhs,
11377 RECUR (TREE_OPERAND (incr, 2))));
11379 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11380 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11381 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11383 tree rhs = TREE_OPERAND (incr, 2);
11384 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11385 RECUR (TREE_OPERAND (incr, 0)),
11386 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11387 RECUR (TREE_OPERAND (rhs, 0)),
11388 RECUR (TREE_OPERAND (rhs, 1))));
11391 incr = RECUR (incr);
11394 incr = RECUR (incr);
11398 TREE_VEC_ELT (declv, i) = decl;
11399 TREE_VEC_ELT (initv, i) = init;
11400 TREE_VEC_ELT (condv, i) = cond;
11401 TREE_VEC_ELT (incrv, i) = incr;
11405 /* Like tsubst_copy for expressions, etc. but also does semantic
11409 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11410 bool integral_constant_expression_p)
11412 #define RECUR(NODE) \
11413 tsubst_expr ((NODE), args, complain, in_decl, \
11414 integral_constant_expression_p)
11418 if (t == NULL_TREE || t == error_mark_node)
11421 if (EXPR_HAS_LOCATION (t))
11422 input_location = EXPR_LOCATION (t);
11423 if (STATEMENT_CODE_P (TREE_CODE (t)))
11424 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11426 switch (TREE_CODE (t))
11428 case STATEMENT_LIST:
11430 tree_stmt_iterator i;
11431 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11432 RECUR (tsi_stmt (i));
11436 case CTOR_INITIALIZER:
11437 finish_mem_initializers (tsubst_initializer_list
11438 (TREE_OPERAND (t, 0), args));
11442 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11446 tmp = RECUR (EXPR_STMT_EXPR (t));
11447 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11448 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11450 finish_expr_stmt (tmp);
11454 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11462 decl = DECL_EXPR_DECL (t);
11463 if (TREE_CODE (decl) == LABEL_DECL)
11464 finish_label_decl (DECL_NAME (decl));
11465 else if (TREE_CODE (decl) == USING_DECL)
11467 tree scope = USING_DECL_SCOPE (decl);
11468 tree name = DECL_NAME (decl);
11471 scope = RECUR (scope);
11472 decl = lookup_qualified_name (scope, name,
11473 /*is_type_p=*/false,
11474 /*complain=*/false);
11475 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11476 qualified_name_lookup_error (scope, name, decl, input_location);
11478 do_local_using_decl (decl, scope, name);
11482 init = DECL_INITIAL (decl);
11483 decl = tsubst (decl, args, complain, in_decl);
11484 if (decl != error_mark_node)
11486 /* By marking the declaration as instantiated, we avoid
11487 trying to instantiate it. Since instantiate_decl can't
11488 handle local variables, and since we've already done
11489 all that needs to be done, that's the right thing to
11491 if (TREE_CODE (decl) == VAR_DECL)
11492 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11493 if (TREE_CODE (decl) == VAR_DECL
11494 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11495 /* Anonymous aggregates are a special case. */
11496 finish_anon_union (decl);
11499 maybe_push_decl (decl);
11500 if (TREE_CODE (decl) == VAR_DECL
11501 && DECL_PRETTY_FUNCTION_P (decl))
11503 /* For __PRETTY_FUNCTION__ we have to adjust the
11505 const char *const name
11506 = cxx_printable_name (current_function_decl, 2);
11507 init = cp_fname_init (name, &TREE_TYPE (decl));
11511 tree t = RECUR (init);
11514 /* If we had an initializer but it
11515 instantiated to nothing,
11516 value-initialize the object. This will
11517 only occur when the initializer was a
11518 pack expansion where the parameter packs
11519 used in that expansion were of length
11521 init = build_value_init (TREE_TYPE (decl));
11526 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11531 /* A DECL_EXPR can also be used as an expression, in the condition
11532 clause of an if/for/while construct. */
11537 stmt = begin_for_stmt ();
11538 RECUR (FOR_INIT_STMT (t));
11539 finish_for_init_stmt (stmt);
11540 tmp = RECUR (FOR_COND (t));
11541 finish_for_cond (tmp, stmt);
11542 tmp = RECUR (FOR_EXPR (t));
11543 finish_for_expr (tmp, stmt);
11544 RECUR (FOR_BODY (t));
11545 finish_for_stmt (stmt);
11549 stmt = begin_while_stmt ();
11550 tmp = RECUR (WHILE_COND (t));
11551 finish_while_stmt_cond (tmp, stmt);
11552 RECUR (WHILE_BODY (t));
11553 finish_while_stmt (stmt);
11557 stmt = begin_do_stmt ();
11558 RECUR (DO_BODY (t));
11559 finish_do_body (stmt);
11560 tmp = RECUR (DO_COND (t));
11561 finish_do_stmt (tmp, stmt);
11565 stmt = begin_if_stmt ();
11566 tmp = RECUR (IF_COND (t));
11567 finish_if_stmt_cond (tmp, stmt);
11568 RECUR (THEN_CLAUSE (t));
11569 finish_then_clause (stmt);
11571 if (ELSE_CLAUSE (t))
11573 begin_else_clause (stmt);
11574 RECUR (ELSE_CLAUSE (t));
11575 finish_else_clause (stmt);
11578 finish_if_stmt (stmt);
11582 if (BIND_EXPR_BODY_BLOCK (t))
11583 stmt = begin_function_body ();
11585 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11586 ? BCS_TRY_BLOCK : 0);
11588 RECUR (BIND_EXPR_BODY (t));
11590 if (BIND_EXPR_BODY_BLOCK (t))
11591 finish_function_body (stmt);
11593 finish_compound_stmt (stmt);
11597 finish_break_stmt ();
11600 case CONTINUE_STMT:
11601 finish_continue_stmt ();
11605 stmt = begin_switch_stmt ();
11606 tmp = RECUR (SWITCH_STMT_COND (t));
11607 finish_switch_cond (tmp, stmt);
11608 RECUR (SWITCH_STMT_BODY (t));
11609 finish_switch_stmt (stmt);
11612 case CASE_LABEL_EXPR:
11613 finish_case_label (EXPR_LOCATION (t),
11614 RECUR (CASE_LOW (t)),
11615 RECUR (CASE_HIGH (t)));
11620 tree decl = LABEL_EXPR_LABEL (t);
11623 label = finish_label_stmt (DECL_NAME (decl));
11624 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11625 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11630 tmp = GOTO_DESTINATION (t);
11631 if (TREE_CODE (tmp) != LABEL_DECL)
11632 /* Computed goto's must be tsubst'd into. On the other hand,
11633 non-computed gotos must not be; the identifier in question
11634 will have no binding. */
11637 tmp = DECL_NAME (tmp);
11638 finish_goto_stmt (tmp);
11642 tmp = finish_asm_stmt
11643 (ASM_VOLATILE_P (t),
11644 RECUR (ASM_STRING (t)),
11645 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11646 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11647 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11648 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11650 tree asm_expr = tmp;
11651 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11652 asm_expr = TREE_OPERAND (asm_expr, 0);
11653 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11660 stmt = begin_try_block ();
11661 RECUR (TRY_STMTS (t));
11662 finish_cleanup_try_block (stmt);
11663 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11667 tree compound_stmt = NULL_TREE;
11669 if (FN_TRY_BLOCK_P (t))
11670 stmt = begin_function_try_block (&compound_stmt);
11672 stmt = begin_try_block ();
11674 RECUR (TRY_STMTS (t));
11676 if (FN_TRY_BLOCK_P (t))
11677 finish_function_try_block (stmt);
11679 finish_try_block (stmt);
11681 RECUR (TRY_HANDLERS (t));
11682 if (FN_TRY_BLOCK_P (t))
11683 finish_function_handler_sequence (stmt, compound_stmt);
11685 finish_handler_sequence (stmt);
11691 tree decl = HANDLER_PARMS (t);
11695 decl = tsubst (decl, args, complain, in_decl);
11696 /* Prevent instantiate_decl from trying to instantiate
11697 this variable. We've already done all that needs to be
11699 if (decl != error_mark_node)
11700 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11702 stmt = begin_handler ();
11703 finish_handler_parms (decl, stmt);
11704 RECUR (HANDLER_BODY (t));
11705 finish_handler (stmt);
11710 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11713 case STATIC_ASSERT:
11716 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11719 /*integral_constant_expression_p=*/true);
11720 finish_static_assert (condition,
11721 STATIC_ASSERT_MESSAGE (t),
11722 STATIC_ASSERT_SOURCE_LOCATION (t),
11723 /*member_p=*/false);
11728 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11729 args, complain, in_decl);
11730 stmt = begin_omp_parallel ();
11731 RECUR (OMP_PARALLEL_BODY (t));
11732 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11733 = OMP_PARALLEL_COMBINED (t);
11737 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11738 args, complain, in_decl);
11739 stmt = begin_omp_task ();
11740 RECUR (OMP_TASK_BODY (t));
11741 finish_omp_task (tmp, stmt);
11746 tree clauses, body, pre_body;
11747 tree declv, initv, condv, incrv;
11750 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11751 args, complain, in_decl);
11752 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11753 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11754 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11755 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11757 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11758 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11759 &clauses, args, complain, in_decl,
11760 integral_constant_expression_p);
11762 stmt = begin_omp_structured_block ();
11764 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11765 if (TREE_VEC_ELT (initv, i) == NULL
11766 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11767 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11768 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11770 tree init = RECUR (TREE_VEC_ELT (initv, i));
11771 gcc_assert (init == TREE_VEC_ELT (declv, i));
11772 TREE_VEC_ELT (initv, i) = NULL_TREE;
11776 tree decl_expr = TREE_VEC_ELT (initv, i);
11777 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11778 gcc_assert (init != NULL);
11779 TREE_VEC_ELT (initv, i) = RECUR (init);
11780 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11782 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11785 pre_body = push_stmt_list ();
11786 RECUR (OMP_FOR_PRE_BODY (t));
11787 pre_body = pop_stmt_list (pre_body);
11789 body = push_stmt_list ();
11790 RECUR (OMP_FOR_BODY (t));
11791 body = pop_stmt_list (body);
11793 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11794 body, pre_body, clauses);
11796 add_stmt (finish_omp_structured_block (stmt));
11802 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11803 stmt = push_stmt_list ();
11804 RECUR (OMP_BODY (t));
11805 stmt = pop_stmt_list (stmt);
11808 OMP_BODY (t) = stmt;
11809 OMP_CLAUSES (t) = tmp;
11817 stmt = push_stmt_list ();
11818 RECUR (OMP_BODY (t));
11819 stmt = pop_stmt_list (stmt);
11822 OMP_BODY (t) = stmt;
11827 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11829 tree op1 = TREE_OPERAND (t, 1);
11830 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11831 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11832 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11836 case EXPR_PACK_EXPANSION:
11837 error ("invalid use of pack expansion expression");
11838 return error_mark_node;
11840 case NONTYPE_ARGUMENT_PACK:
11841 error ("use %<...%> to expand argument pack");
11842 return error_mark_node;
11845 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11847 return tsubst_copy_and_build (t, args, complain, in_decl,
11848 /*function_p=*/false,
11849 integral_constant_expression_p);
11856 /* T is a postfix-expression that is not being used in a function
11857 call. Return the substituted version of T. */
11860 tsubst_non_call_postfix_expression (tree t, tree args,
11861 tsubst_flags_t complain,
11864 if (TREE_CODE (t) == SCOPE_REF)
11865 t = tsubst_qualified_id (t, args, complain, in_decl,
11866 /*done=*/false, /*address_p=*/false);
11868 t = tsubst_copy_and_build (t, args, complain, in_decl,
11869 /*function_p=*/false,
11870 /*integral_constant_expression_p=*/false);
11875 /* Like tsubst but deals with expressions and performs semantic
11876 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11879 tsubst_copy_and_build (tree t,
11881 tsubst_flags_t complain,
11884 bool integral_constant_expression_p)
11886 #define RECUR(NODE) \
11887 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11888 /*function_p=*/false, \
11889 integral_constant_expression_p)
11893 if (t == NULL_TREE || t == error_mark_node)
11896 switch (TREE_CODE (t))
11900 /* Fall through. */
11901 case IDENTIFIER_NODE:
11905 bool non_integral_constant_expression_p;
11906 const char *error_msg;
11908 if (IDENTIFIER_TYPENAME_P (t))
11910 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11911 t = mangle_conv_op_name_for_type (new_type);
11914 /* Look up the name. */
11915 decl = lookup_name (t);
11917 /* By convention, expressions use ERROR_MARK_NODE to indicate
11918 failure, not NULL_TREE. */
11919 if (decl == NULL_TREE)
11920 decl = error_mark_node;
11922 decl = finish_id_expression (t, decl, NULL_TREE,
11924 integral_constant_expression_p,
11925 /*allow_non_integral_constant_expression_p=*/false,
11926 &non_integral_constant_expression_p,
11927 /*template_p=*/false,
11929 /*address_p=*/false,
11930 /*template_arg_p=*/false,
11935 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11936 decl = unqualified_name_lookup_error (decl);
11940 case TEMPLATE_ID_EXPR:
11943 tree templ = RECUR (TREE_OPERAND (t, 0));
11944 tree targs = TREE_OPERAND (t, 1);
11947 targs = tsubst_template_args (targs, args, complain, in_decl);
11949 if (TREE_CODE (templ) == COMPONENT_REF)
11951 object = TREE_OPERAND (templ, 0);
11952 templ = TREE_OPERAND (templ, 1);
11955 object = NULL_TREE;
11956 templ = lookup_template_function (templ, targs);
11959 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11960 object, templ, NULL_TREE);
11962 return baselink_for_fns (templ);
11967 tree r = RECUR (TREE_OPERAND (t, 0));
11969 if (REFERENCE_REF_P (t))
11971 /* A type conversion to reference type will be enclosed in
11972 such an indirect ref, but the substitution of the cast
11973 will have also added such an indirect ref. */
11974 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11975 r = convert_from_reference (r);
11978 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
11984 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11985 RECUR (TREE_OPERAND (t, 0)));
11988 case REINTERPRET_CAST_EXPR:
11989 case CONST_CAST_EXPR:
11990 case DYNAMIC_CAST_EXPR:
11991 case STATIC_CAST_EXPR:
11996 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11997 if (integral_constant_expression_p
11998 && !cast_valid_in_integral_constant_expression_p (type))
12000 if (complain & tf_error)
12001 error ("a cast to a type other than an integral or "
12002 "enumeration type cannot appear in a constant-expression");
12003 return error_mark_node;
12006 op = RECUR (TREE_OPERAND (t, 0));
12008 switch (TREE_CODE (t))
12011 return build_functional_cast (type, op, complain);
12012 case REINTERPRET_CAST_EXPR:
12013 return build_reinterpret_cast (type, op, complain);
12014 case CONST_CAST_EXPR:
12015 return build_const_cast (type, op, complain);
12016 case DYNAMIC_CAST_EXPR:
12017 return build_dynamic_cast (type, op, complain);
12018 case STATIC_CAST_EXPR:
12019 return build_static_cast (type, op, complain);
12021 gcc_unreachable ();
12025 case POSTDECREMENT_EXPR:
12026 case POSTINCREMENT_EXPR:
12027 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12028 args, complain, in_decl);
12029 return build_x_unary_op (TREE_CODE (t), op1, complain);
12031 case PREDECREMENT_EXPR:
12032 case PREINCREMENT_EXPR:
12036 case TRUTH_NOT_EXPR:
12037 case UNARY_PLUS_EXPR: /* Unary + */
12038 case REALPART_EXPR:
12039 case IMAGPART_EXPR:
12040 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
12044 op1 = TREE_OPERAND (t, 0);
12045 if (TREE_CODE (op1) == SCOPE_REF)
12046 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
12047 /*done=*/true, /*address_p=*/true);
12049 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
12051 if (TREE_CODE (op1) == LABEL_DECL)
12052 return finish_label_address_expr (DECL_NAME (op1),
12053 EXPR_LOCATION (op1));
12054 return build_x_unary_op (ADDR_EXPR, op1, complain);
12059 case TRUNC_DIV_EXPR:
12060 case CEIL_DIV_EXPR:
12061 case FLOOR_DIV_EXPR:
12062 case ROUND_DIV_EXPR:
12063 case EXACT_DIV_EXPR:
12067 case TRUNC_MOD_EXPR:
12068 case FLOOR_MOD_EXPR:
12069 case TRUTH_ANDIF_EXPR:
12070 case TRUTH_ORIF_EXPR:
12071 case TRUTH_AND_EXPR:
12072 case TRUTH_OR_EXPR:
12087 return build_x_binary_op
12089 RECUR (TREE_OPERAND (t, 0)),
12090 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
12092 : TREE_CODE (TREE_OPERAND (t, 0))),
12093 RECUR (TREE_OPERAND (t, 1)),
12094 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
12096 : TREE_CODE (TREE_OPERAND (t, 1))),
12097 /*overloaded_p=*/NULL,
12101 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
12102 /*address_p=*/false);
12104 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12105 args, complain, in_decl);
12106 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
12109 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12110 return tsubst_copy (t, args, complain, in_decl);
12114 op1 = TREE_OPERAND (t, 0);
12117 /* When there are no ARGS, we are trying to evaluate a
12118 non-dependent expression from the parser. Trying to do
12119 the substitutions may not work. */
12121 op1 = TREE_TYPE (op1);
12125 ++cp_unevaluated_operand;
12126 ++c_inhibit_evaluation_warnings;
12127 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
12128 /*function_p=*/false,
12129 /*integral_constant_expression_p=*/false);
12130 --cp_unevaluated_operand;
12131 --c_inhibit_evaluation_warnings;
12134 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
12135 complain & tf_error);
12137 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
12138 complain & tf_error);
12142 tree r = build_x_modify_expr
12143 (RECUR (TREE_OPERAND (t, 0)),
12144 TREE_CODE (TREE_OPERAND (t, 1)),
12145 RECUR (TREE_OPERAND (t, 2)),
12147 /* TREE_NO_WARNING must be set if either the expression was
12148 parenthesized or it uses an operator such as >>= rather
12149 than plain assignment. In the former case, it was already
12150 set and must be copied. In the latter case,
12151 build_x_modify_expr sets it and it must not be reset
12153 if (TREE_NO_WARNING (t))
12154 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12159 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12160 args, complain, in_decl);
12161 /* Remember that there was a reference to this entity. */
12164 return build_x_arrow (op1);
12168 tree placement = RECUR (TREE_OPERAND (t, 0));
12169 tree init = RECUR (TREE_OPERAND (t, 3));
12170 VEC(tree,gc) *placement_vec;
12171 VEC(tree,gc) *init_vec;
12174 if (placement == NULL_TREE)
12175 placement_vec = NULL;
12178 placement_vec = make_tree_vector ();
12179 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
12180 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
12183 /* If there was an initializer in the original tree, but it
12184 instantiated to an empty list, then we should pass a
12185 non-NULL empty vector to tell build_new that it was an
12186 empty initializer() rather than no initializer. This can
12187 only happen when the initializer is a pack expansion whose
12188 parameter packs are of length zero. */
12189 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
12193 init_vec = make_tree_vector ();
12194 if (init == void_zero_node)
12195 gcc_assert (init_vec != NULL);
12198 for (; init != NULL_TREE; init = TREE_CHAIN (init))
12199 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
12203 ret = build_new (&placement_vec,
12204 RECUR (TREE_OPERAND (t, 1)),
12205 RECUR (TREE_OPERAND (t, 2)),
12207 NEW_EXPR_USE_GLOBAL (t),
12210 if (placement_vec != NULL)
12211 release_tree_vector (placement_vec);
12212 if (init_vec != NULL)
12213 release_tree_vector (init_vec);
12219 return delete_sanity
12220 (RECUR (TREE_OPERAND (t, 0)),
12221 RECUR (TREE_OPERAND (t, 1)),
12222 DELETE_EXPR_USE_VEC (t),
12223 DELETE_EXPR_USE_GLOBAL (t));
12225 case COMPOUND_EXPR:
12226 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
12227 RECUR (TREE_OPERAND (t, 1)),
12233 VEC(tree,gc) *call_args;
12234 unsigned int nargs, i;
12239 function = CALL_EXPR_FN (t);
12240 /* When we parsed the expression, we determined whether or
12241 not Koenig lookup should be performed. */
12242 koenig_p = KOENIG_LOOKUP_P (t);
12243 if (TREE_CODE (function) == SCOPE_REF)
12245 qualified_p = true;
12246 function = tsubst_qualified_id (function, args, complain, in_decl,
12248 /*address_p=*/false);
12252 if (TREE_CODE (function) == COMPONENT_REF)
12254 tree op = TREE_OPERAND (function, 1);
12256 qualified_p = (TREE_CODE (op) == SCOPE_REF
12257 || (BASELINK_P (op)
12258 && BASELINK_QUALIFIED_P (op)));
12261 qualified_p = false;
12263 function = tsubst_copy_and_build (function, args, complain,
12266 integral_constant_expression_p);
12268 if (BASELINK_P (function))
12269 qualified_p = true;
12272 nargs = call_expr_nargs (t);
12273 call_args = make_tree_vector ();
12274 for (i = 0; i < nargs; ++i)
12276 tree arg = CALL_EXPR_ARG (t, i);
12278 if (!PACK_EXPANSION_P (arg))
12279 VEC_safe_push (tree, gc, call_args,
12280 RECUR (CALL_EXPR_ARG (t, i)));
12283 /* Expand the pack expansion and push each entry onto
12285 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12286 if (TREE_CODE (arg) == TREE_VEC)
12288 unsigned int len, j;
12290 len = TREE_VEC_LENGTH (arg);
12291 for (j = 0; j < len; ++j)
12293 tree value = TREE_VEC_ELT (arg, j);
12294 if (value != NULL_TREE)
12295 value = convert_from_reference (value);
12296 VEC_safe_push (tree, gc, call_args, value);
12301 /* A partial substitution. Add one entry. */
12302 VEC_safe_push (tree, gc, call_args, arg);
12307 /* We do not perform argument-dependent lookup if normal
12308 lookup finds a non-function, in accordance with the
12309 expected resolution of DR 218. */
12311 && ((is_overloaded_fn (function)
12312 /* If lookup found a member function, the Koenig lookup is
12313 not appropriate, even if an unqualified-name was used
12314 to denote the function. */
12315 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12316 || TREE_CODE (function) == IDENTIFIER_NODE)
12317 /* Only do this when substitution turns a dependent call
12318 into a non-dependent call. */
12319 && type_dependent_expression_p_push (t)
12320 && !any_type_dependent_arguments_p (call_args))
12321 function = perform_koenig_lookup (function, call_args);
12323 if (TREE_CODE (function) == IDENTIFIER_NODE)
12325 unqualified_name_lookup_error (function);
12326 release_tree_vector (call_args);
12327 return error_mark_node;
12330 /* Remember that there was a reference to this entity. */
12331 if (DECL_P (function))
12332 mark_used (function);
12334 if (TREE_CODE (function) == OFFSET_REF)
12335 ret = build_offset_ref_call_from_tree (function, &call_args);
12336 else if (TREE_CODE (function) == COMPONENT_REF)
12338 if (!BASELINK_P (TREE_OPERAND (function, 1)))
12339 ret = finish_call_expr (function, &call_args,
12340 /*disallow_virtual=*/false,
12341 /*koenig_p=*/false,
12344 ret = (build_new_method_call
12345 (TREE_OPERAND (function, 0),
12346 TREE_OPERAND (function, 1),
12347 &call_args, NULL_TREE,
12348 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12353 ret = finish_call_expr (function, &call_args,
12354 /*disallow_virtual=*/qualified_p,
12358 release_tree_vector (call_args);
12364 return build_x_conditional_expr
12365 (RECUR (TREE_OPERAND (t, 0)),
12366 RECUR (TREE_OPERAND (t, 1)),
12367 RECUR (TREE_OPERAND (t, 2)),
12370 case PSEUDO_DTOR_EXPR:
12371 return finish_pseudo_destructor_expr
12372 (RECUR (TREE_OPERAND (t, 0)),
12373 RECUR (TREE_OPERAND (t, 1)),
12374 RECUR (TREE_OPERAND (t, 2)));
12378 tree purpose, value, chain;
12380 if (t == void_list_node)
12383 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12384 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12386 /* We have pack expansions, so expand those and
12387 create a new list out of it. */
12388 tree purposevec = NULL_TREE;
12389 tree valuevec = NULL_TREE;
12393 /* Expand the argument expressions. */
12394 if (TREE_PURPOSE (t))
12395 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12396 complain, in_decl);
12397 if (TREE_VALUE (t))
12398 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12399 complain, in_decl);
12401 /* Build the rest of the list. */
12402 chain = TREE_CHAIN (t);
12403 if (chain && chain != void_type_node)
12404 chain = RECUR (chain);
12406 /* Determine the number of arguments. */
12407 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12409 len = TREE_VEC_LENGTH (purposevec);
12410 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12412 else if (TREE_CODE (valuevec) == TREE_VEC)
12413 len = TREE_VEC_LENGTH (valuevec);
12416 /* Since we only performed a partial substitution into
12417 the argument pack, we only return a single list
12419 if (purposevec == TREE_PURPOSE (t)
12420 && valuevec == TREE_VALUE (t)
12421 && chain == TREE_CHAIN (t))
12424 return tree_cons (purposevec, valuevec, chain);
12427 /* Convert the argument vectors into a TREE_LIST */
12431 /* Grab the Ith values. */
12433 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12436 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12439 /* Build the list (backwards). */
12440 chain = tree_cons (purpose, value, chain);
12446 purpose = TREE_PURPOSE (t);
12448 purpose = RECUR (purpose);
12449 value = TREE_VALUE (t);
12451 value = RECUR (value);
12452 chain = TREE_CHAIN (t);
12453 if (chain && chain != void_type_node)
12454 chain = RECUR (chain);
12455 if (purpose == TREE_PURPOSE (t)
12456 && value == TREE_VALUE (t)
12457 && chain == TREE_CHAIN (t))
12459 return tree_cons (purpose, value, chain);
12462 case COMPONENT_REF:
12468 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12469 args, complain, in_decl);
12470 /* Remember that there was a reference to this entity. */
12471 if (DECL_P (object))
12472 mark_used (object);
12473 object_type = TREE_TYPE (object);
12475 member = TREE_OPERAND (t, 1);
12476 if (BASELINK_P (member))
12477 member = tsubst_baselink (member,
12478 non_reference (TREE_TYPE (object)),
12479 args, complain, in_decl);
12481 member = tsubst_copy (member, args, complain, in_decl);
12482 if (member == error_mark_node)
12483 return error_mark_node;
12485 if (object_type && !CLASS_TYPE_P (object_type))
12487 if (SCALAR_TYPE_P (object_type))
12489 tree s = NULL_TREE;
12490 tree dtor = member;
12492 if (TREE_CODE (dtor) == SCOPE_REF)
12494 s = TREE_OPERAND (dtor, 0);
12495 dtor = TREE_OPERAND (dtor, 1);
12497 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12499 dtor = TREE_OPERAND (dtor, 0);
12501 return finish_pseudo_destructor_expr (object, s, dtor);
12505 else if (TREE_CODE (member) == SCOPE_REF
12506 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12511 /* Lookup the template functions now that we know what the
12513 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12514 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12515 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12516 /*is_type_p=*/false,
12517 /*complain=*/false);
12518 if (BASELINK_P (member))
12520 BASELINK_FUNCTIONS (member)
12521 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12523 member = (adjust_result_of_qualified_name_lookup
12524 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12529 qualified_name_lookup_error (object_type, tmpl, member,
12531 return error_mark_node;
12534 else if (TREE_CODE (member) == SCOPE_REF
12535 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12536 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12538 if (complain & tf_error)
12540 if (TYPE_P (TREE_OPERAND (member, 0)))
12541 error ("%qT is not a class or namespace",
12542 TREE_OPERAND (member, 0));
12544 error ("%qD is not a class or namespace",
12545 TREE_OPERAND (member, 0));
12547 return error_mark_node;
12549 else if (TREE_CODE (member) == FIELD_DECL)
12550 return finish_non_static_data_member (member, object, NULL_TREE);
12552 return finish_class_member_access_expr (object, member,
12553 /*template_p=*/false,
12559 (RECUR (TREE_OPERAND (t, 0)));
12563 VEC(constructor_elt,gc) *n;
12564 constructor_elt *ce;
12565 unsigned HOST_WIDE_INT idx;
12566 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12567 bool process_index_p;
12569 bool need_copy_p = false;
12572 if (type == error_mark_node)
12573 return error_mark_node;
12575 /* digest_init will do the wrong thing if we let it. */
12576 if (type && TYPE_PTRMEMFUNC_P (type))
12579 /* We do not want to process the index of aggregate
12580 initializers as they are identifier nodes which will be
12581 looked up by digest_init. */
12582 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12584 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12585 newlen = VEC_length (constructor_elt, n);
12586 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12588 if (ce->index && process_index_p)
12589 ce->index = RECUR (ce->index);
12591 if (PACK_EXPANSION_P (ce->value))
12593 /* Substitute into the pack expansion. */
12594 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12597 if (ce->value == error_mark_node)
12599 else if (TREE_VEC_LENGTH (ce->value) == 1)
12600 /* Just move the argument into place. */
12601 ce->value = TREE_VEC_ELT (ce->value, 0);
12604 /* Update the length of the final CONSTRUCTOR
12605 arguments vector, and note that we will need to
12607 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12608 need_copy_p = true;
12612 ce->value = RECUR (ce->value);
12617 VEC(constructor_elt,gc) *old_n = n;
12619 n = VEC_alloc (constructor_elt, gc, newlen);
12620 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12623 if (TREE_CODE (ce->value) == TREE_VEC)
12625 int i, len = TREE_VEC_LENGTH (ce->value);
12626 for (i = 0; i < len; ++i)
12627 CONSTRUCTOR_APPEND_ELT (n, 0,
12628 TREE_VEC_ELT (ce->value, i));
12631 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12635 r = build_constructor (init_list_type_node, n);
12636 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12638 if (TREE_HAS_CONSTRUCTOR (t))
12639 return finish_compound_literal (type, r);
12646 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12647 if (TYPE_P (operand_0))
12648 return get_typeid (operand_0);
12649 return build_typeid (operand_0);
12659 tree r = tsubst_copy (t, args, complain, in_decl);
12661 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12662 /* If the original type was a reference, we'll be wrapped in
12663 the appropriate INDIRECT_REF. */
12664 r = convert_from_reference (r);
12669 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12670 tsubst_copy (TREE_TYPE (t), args, complain,
12673 case OFFSETOF_EXPR:
12674 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12678 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12679 complain, in_decl);
12681 tree type2 = TRAIT_EXPR_TYPE2 (t);
12683 type2 = tsubst_copy (type2, args, complain, in_decl);
12685 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12690 tree old_stmt_expr = cur_stmt_expr;
12691 tree stmt_expr = begin_stmt_expr ();
12693 cur_stmt_expr = stmt_expr;
12694 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12695 integral_constant_expression_p);
12696 stmt_expr = finish_stmt_expr (stmt_expr, false);
12697 cur_stmt_expr = old_stmt_expr;
12699 /* If the resulting list of expression statement is empty,
12700 fold it further into void_zero_node. */
12701 if (empty_expr_stmt_p (stmt_expr))
12702 stmt_expr = void_zero_node;
12708 t = tsubst_copy (t, args, complain, in_decl);
12709 /* As in finish_id_expression, we resolve enumeration constants
12710 to their underlying values. */
12711 if (TREE_CODE (t) == CONST_DECL)
12713 used_types_insert (TREE_TYPE (t));
12714 return DECL_INITIAL (t);
12720 tree r = build_lambda_expr ();
12722 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12723 TREE_TYPE (r) = type;
12724 CLASSTYPE_LAMBDA_EXPR (type) = r;
12726 LAMBDA_EXPR_LOCATION (r)
12727 = LAMBDA_EXPR_LOCATION (t);
12728 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12729 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12730 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12731 LAMBDA_EXPR_DISCRIMINATOR (r)
12732 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12733 LAMBDA_EXPR_CAPTURE_LIST (r)
12734 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12735 LAMBDA_EXPR_THIS_CAPTURE (r)
12736 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12737 LAMBDA_EXPR_EXTRA_SCOPE (r)
12738 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12740 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12741 determine_visibility (TYPE_NAME (type));
12742 /* Now that we know visibility, instantiate the type so we have a
12743 declaration of the op() for later calls to lambda_function. */
12744 complete_type (type);
12746 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12748 apply_lambda_return_type (r, type);
12750 return build_lambda_object (r);
12754 /* Handle Objective-C++ constructs, if appropriate. */
12757 = objcp_tsubst_copy_and_build (t, args, complain,
12758 in_decl, /*function_p=*/false);
12762 return tsubst_copy (t, args, complain, in_decl);
12768 /* Verify that the instantiated ARGS are valid. For type arguments,
12769 make sure that the type's linkage is ok. For non-type arguments,
12770 make sure they are constants if they are integral or enumerations.
12771 Emit an error under control of COMPLAIN, and return TRUE on error. */
12774 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12776 if (ARGUMENT_PACK_P (t))
12778 tree vec = ARGUMENT_PACK_ARGS (t);
12779 int len = TREE_VEC_LENGTH (vec);
12780 bool result = false;
12783 for (i = 0; i < len; ++i)
12784 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12788 else if (TYPE_P (t))
12790 /* [basic.link]: A name with no linkage (notably, the name
12791 of a class or enumeration declared in a local scope)
12792 shall not be used to declare an entity with linkage.
12793 This implies that names with no linkage cannot be used as
12796 DR 757 relaxes this restriction for C++0x. */
12797 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
12798 : no_linkage_check (t, /*relaxed_p=*/false));
12802 /* DR 488 makes use of a type with no linkage cause
12803 type deduction to fail. */
12804 if (complain & tf_error)
12806 if (TYPE_ANONYMOUS_P (nt))
12807 error ("%qT is/uses anonymous type", t);
12809 error ("template argument for %qD uses local type %qT",
12814 /* In order to avoid all sorts of complications, we do not
12815 allow variably-modified types as template arguments. */
12816 else if (variably_modified_type_p (t, NULL_TREE))
12818 if (complain & tf_error)
12819 error ("%qT is a variably modified type", t);
12823 /* A non-type argument of integral or enumerated type must be a
12825 else if (TREE_TYPE (t)
12826 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12827 && !TREE_CONSTANT (t))
12829 if (complain & tf_error)
12830 error ("integral expression %qE is not constant", t);
12837 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12839 int ix, len = DECL_NTPARMS (tmpl);
12840 bool result = false;
12842 for (ix = 0; ix != len; ix++)
12844 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12847 if (result && (complain & tf_error))
12848 error (" trying to instantiate %qD", tmpl);
12852 /* Instantiate the indicated variable or function template TMPL with
12853 the template arguments in TARG_PTR. */
12856 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12858 tree targ_ptr = orig_args;
12862 HOST_WIDE_INT saved_processing_template_decl;
12864 if (tmpl == error_mark_node)
12865 return error_mark_node;
12867 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12869 /* If this function is a clone, handle it specially. */
12870 if (DECL_CLONED_FUNCTION_P (tmpl))
12875 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12876 DECL_CLONED_FUNCTION. */
12877 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12878 targ_ptr, complain);
12879 if (spec == error_mark_node)
12880 return error_mark_node;
12882 /* Look for the clone. */
12883 FOR_EACH_CLONE (clone, spec)
12884 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12886 /* We should always have found the clone by now. */
12887 gcc_unreachable ();
12891 /* Check to see if we already have this specialization. */
12892 gen_tmpl = most_general_template (tmpl);
12893 if (tmpl != gen_tmpl)
12894 /* The TMPL is a partial instantiation. To get a full set of
12895 arguments we must add the arguments used to perform the
12896 partial instantiation. */
12897 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12900 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12901 but it doesn't seem to be on the hot path. */
12902 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12904 gcc_assert (tmpl == gen_tmpl
12905 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12907 || fndecl == NULL_TREE);
12909 if (spec != NULL_TREE)
12912 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12914 return error_mark_node;
12916 /* We are building a FUNCTION_DECL, during which the access of its
12917 parameters and return types have to be checked. However this
12918 FUNCTION_DECL which is the desired context for access checking
12919 is not built yet. We solve this chicken-and-egg problem by
12920 deferring all checks until we have the FUNCTION_DECL. */
12921 push_deferring_access_checks (dk_deferred);
12923 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12924 (because, for example, we have encountered a non-dependent
12925 function call in the body of a template function and must now
12926 determine which of several overloaded functions will be called),
12927 within the instantiation itself we are not processing a
12929 saved_processing_template_decl = processing_template_decl;
12930 processing_template_decl = 0;
12931 /* Substitute template parameters to obtain the specialization. */
12932 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12933 targ_ptr, complain, gen_tmpl);
12934 processing_template_decl = saved_processing_template_decl;
12935 if (fndecl == error_mark_node)
12936 return error_mark_node;
12938 /* Now we know the specialization, compute access previously
12940 push_access_scope (fndecl);
12942 /* Some typedefs referenced from within the template code need to be access
12943 checked at template instantiation time, i.e now. These types were
12944 added to the template at parsing time. Let's get those and perfom
12945 the acces checks then. */
12946 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12947 perform_deferred_access_checks ();
12948 pop_access_scope (fndecl);
12949 pop_deferring_access_checks ();
12951 /* The DECL_TI_TEMPLATE should always be the immediate parent
12952 template, not the most general template. */
12953 DECL_TI_TEMPLATE (fndecl) = tmpl;
12955 /* If we've just instantiated the main entry point for a function,
12956 instantiate all the alternate entry points as well. We do this
12957 by cloning the instantiation of the main entry point, not by
12958 instantiating the template clones. */
12959 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12960 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12965 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12966 NARGS elements of the arguments that are being used when calling
12967 it. TARGS is a vector into which the deduced template arguments
12970 Return zero for success, 2 for an incomplete match that doesn't resolve
12971 all the types, and 1 for complete failure. An error message will be
12972 printed only for an incomplete match.
12974 If FN is a conversion operator, or we are trying to produce a specific
12975 specialization, RETURN_TYPE is the return type desired.
12977 The EXPLICIT_TARGS are explicit template arguments provided via a
12980 The parameter STRICT is one of:
12983 We are deducing arguments for a function call, as in
12984 [temp.deduct.call].
12987 We are deducing arguments for a conversion function, as in
12988 [temp.deduct.conv].
12991 We are deducing arguments when doing an explicit instantiation
12992 as in [temp.explicit], when determining an explicit specialization
12993 as in [temp.expl.spec], or when taking the address of a function
12994 template, as in [temp.deduct.funcaddr]. */
12997 fn_type_unification (tree fn,
12998 tree explicit_targs,
13001 unsigned int nargs,
13003 unification_kind_t strict,
13009 bool incomplete_argument_packs_p = false;
13011 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
13013 fntype = TREE_TYPE (fn);
13014 if (explicit_targs)
13018 The specified template arguments must match the template
13019 parameters in kind (i.e., type, nontype, template), and there
13020 must not be more arguments than there are parameters;
13021 otherwise type deduction fails.
13023 Nontype arguments must match the types of the corresponding
13024 nontype template parameters, or must be convertible to the
13025 types of the corresponding nontype parameters as specified in
13026 _temp.arg.nontype_, otherwise type deduction fails.
13028 All references in the function type of the function template
13029 to the corresponding template parameters are replaced by the
13030 specified template argument values. If a substitution in a
13031 template parameter or in the function type of the function
13032 template results in an invalid type, type deduction fails. */
13033 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
13034 int i, len = TREE_VEC_LENGTH (tparms);
13035 tree converted_args;
13036 bool incomplete = false;
13038 if (explicit_targs == error_mark_node)
13042 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
13043 /*require_all_args=*/false,
13044 /*use_default_args=*/false));
13045 if (converted_args == error_mark_node)
13048 /* Substitute the explicit args into the function type. This is
13049 necessary so that, for instance, explicitly declared function
13050 arguments can match null pointed constants. If we were given
13051 an incomplete set of explicit args, we must not do semantic
13052 processing during substitution as we could create partial
13054 for (i = 0; i < len; i++)
13056 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13057 bool parameter_pack = false;
13059 /* Dig out the actual parm. */
13060 if (TREE_CODE (parm) == TYPE_DECL
13061 || TREE_CODE (parm) == TEMPLATE_DECL)
13063 parm = TREE_TYPE (parm);
13064 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
13066 else if (TREE_CODE (parm) == PARM_DECL)
13068 parm = DECL_INITIAL (parm);
13069 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
13072 if (parameter_pack)
13076 template_parm_level_and_index (parm, &level, &idx);
13078 /* Mark the argument pack as "incomplete". We could
13079 still deduce more arguments during unification. */
13080 targ = TMPL_ARG (converted_args, level, idx);
13083 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
13084 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
13085 = ARGUMENT_PACK_ARGS (targ);
13088 /* We have some incomplete argument packs. */
13089 incomplete_argument_packs_p = true;
13093 if (incomplete_argument_packs_p)
13094 /* Any substitution is guaranteed to be incomplete if there
13095 are incomplete argument packs, because we can still deduce
13099 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
13101 processing_template_decl += incomplete;
13102 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
13103 processing_template_decl -= incomplete;
13105 if (fntype == error_mark_node)
13108 /* Place the explicitly specified arguments in TARGS. */
13109 for (i = NUM_TMPL_ARGS (converted_args); i--;)
13110 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
13113 /* Never do unification on the 'this' parameter. */
13114 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
13120 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
13121 new_args = XALLOCAVEC (tree, nargs + 1);
13122 new_args[0] = return_type;
13123 memcpy (new_args + 1, args, nargs * sizeof (tree));
13128 /* We allow incomplete unification without an error message here
13129 because the standard doesn't seem to explicitly prohibit it. Our
13130 callers must be ready to deal with unification failures in any
13132 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
13133 targs, parms, args, nargs, /*subr=*/0,
13136 if (result == 0 && incomplete_argument_packs_p)
13138 int i, len = NUM_TMPL_ARGS (targs);
13140 /* Clear the "incomplete" flags on all argument packs. */
13141 for (i = 0; i < len; i++)
13143 tree arg = TREE_VEC_ELT (targs, i);
13144 if (ARGUMENT_PACK_P (arg))
13146 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
13147 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
13152 /* Now that we have bindings for all of the template arguments,
13153 ensure that the arguments deduced for the template template
13154 parameters have compatible template parameter lists. We cannot
13155 check this property before we have deduced all template
13156 arguments, because the template parameter types of a template
13157 template parameter might depend on prior template parameters
13158 deduced after the template template parameter. The following
13159 ill-formed example illustrates this issue:
13161 template<typename T, template<T> class C> void f(C<5>, T);
13163 template<int N> struct X {};
13166 f(X<5>(), 5l); // error: template argument deduction fails
13169 The template parameter list of 'C' depends on the template type
13170 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
13171 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
13172 time that we deduce 'C'. */
13174 && !template_template_parm_bindings_ok_p
13175 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
13179 /* All is well so far. Now, check:
13183 When all template arguments have been deduced, all uses of
13184 template parameters in nondeduced contexts are replaced with
13185 the corresponding deduced argument values. If the
13186 substitution results in an invalid type, as described above,
13187 type deduction fails. */
13189 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
13190 if (substed == error_mark_node)
13193 /* If we're looking for an exact match, check that what we got
13194 is indeed an exact match. It might not be if some template
13195 parameters are used in non-deduced contexts. */
13196 if (strict == DEDUCE_EXACT)
13201 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
13203 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
13204 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
13205 if (!same_type_p (args[i], TREE_VALUE (sarg)))
13213 /* Adjust types before performing type deduction, as described in
13214 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
13215 sections are symmetric. PARM is the type of a function parameter
13216 or the return type of the conversion function. ARG is the type of
13217 the argument passed to the call, or the type of the value
13218 initialized with the result of the conversion function.
13219 ARG_EXPR is the original argument expression, which may be null. */
13222 maybe_adjust_types_for_deduction (unification_kind_t strict,
13236 /* Swap PARM and ARG throughout the remainder of this
13237 function; the handling is precisely symmetric since PARM
13238 will initialize ARG rather than vice versa. */
13246 /* Core issue #873: Do the DR606 thing (see below) for these cases,
13247 too, but here handle it by stripping the reference from PARM
13248 rather than by adding it to ARG. */
13249 if (TREE_CODE (*parm) == REFERENCE_TYPE
13250 && TYPE_REF_IS_RVALUE (*parm)
13251 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13252 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13253 && TREE_CODE (*arg) == REFERENCE_TYPE
13254 && !TYPE_REF_IS_RVALUE (*arg))
13255 *parm = TREE_TYPE (*parm);
13256 /* Nothing else to do in this case. */
13260 gcc_unreachable ();
13263 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13265 /* [temp.deduct.call]
13267 If P is not a reference type:
13269 --If A is an array type, the pointer type produced by the
13270 array-to-pointer standard conversion (_conv.array_) is
13271 used in place of A for type deduction; otherwise,
13273 --If A is a function type, the pointer type produced by
13274 the function-to-pointer standard conversion
13275 (_conv.func_) is used in place of A for type deduction;
13278 --If A is a cv-qualified type, the top level
13279 cv-qualifiers of A's type are ignored for type
13281 if (TREE_CODE (*arg) == ARRAY_TYPE)
13282 *arg = build_pointer_type (TREE_TYPE (*arg));
13283 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13284 *arg = build_pointer_type (*arg);
13286 *arg = TYPE_MAIN_VARIANT (*arg);
13289 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13290 of the form T&&, where T is a template parameter, and the argument
13291 is an lvalue, T is deduced as A& */
13292 if (TREE_CODE (*parm) == REFERENCE_TYPE
13293 && TYPE_REF_IS_RVALUE (*parm)
13294 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13295 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13296 && arg_expr && real_lvalue_p (arg_expr))
13297 *arg = build_reference_type (*arg);
13299 /* [temp.deduct.call]
13301 If P is a cv-qualified type, the top level cv-qualifiers
13302 of P's type are ignored for type deduction. If P is a
13303 reference type, the type referred to by P is used for
13305 *parm = TYPE_MAIN_VARIANT (*parm);
13306 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13308 *parm = TREE_TYPE (*parm);
13309 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13312 /* DR 322. For conversion deduction, remove a reference type on parm
13313 too (which has been swapped into ARG). */
13314 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13315 *arg = TREE_TYPE (*arg);
13320 /* Most parms like fn_type_unification.
13322 If SUBR is 1, we're being called recursively (to unify the
13323 arguments of a function or method parameter of a function
13327 type_unification_real (tree tparms,
13331 unsigned int xnargs,
13333 unification_kind_t strict,
13336 tree parm, arg, arg_expr;
13338 int ntparms = TREE_VEC_LENGTH (tparms);
13340 int saw_undeduced = 0;
13343 unsigned int nargs;
13346 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13347 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13348 gcc_assert (ntparms > 0);
13350 /* Reset the number of non-defaulted template arguments contained
13352 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
13357 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13358 | UNIFY_ALLOW_DERIVED);
13362 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13366 sub_strict = UNIFY_ALLOW_NONE;
13370 gcc_unreachable ();
13379 while (parms && parms != void_list_node
13382 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13385 parm = TREE_VALUE (parms);
13386 parms = TREE_CHAIN (parms);
13391 if (arg == error_mark_node)
13393 if (arg == unknown_type_node)
13394 /* We can't deduce anything from this, but we might get all the
13395 template args from other function args. */
13398 /* Conversions will be performed on a function argument that
13399 corresponds with a function parameter that contains only
13400 non-deducible template parameters and explicitly specified
13401 template parameters. */
13402 if (!uses_template_parms (parm))
13407 type = TREE_TYPE (arg);
13411 if (same_type_p (parm, type))
13413 if (strict != DEDUCE_EXACT
13414 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13423 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13424 if (type_unknown_p (arg))
13426 /* [temp.deduct.type]
13428 A template-argument can be deduced from a pointer to
13429 function or pointer to member function argument if
13430 the set of overloaded functions does not contain
13431 function templates and at most one of a set of
13432 overloaded functions provides a unique match. */
13433 if (resolve_overloaded_unification
13434 (tparms, targs, parm, arg, strict, sub_strict))
13440 arg = unlowered_expr_type (arg);
13441 if (arg == error_mark_node)
13446 int arg_strict = sub_strict;
13449 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13452 if (arg == init_list_type_node && arg_expr)
13454 if (unify (tparms, targs, parm, arg, arg_strict))
13461 && parms != void_list_node
13462 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13464 /* Unify the remaining arguments with the pack expansion type. */
13466 tree parmvec = make_tree_vec (1);
13468 /* Allocate a TREE_VEC and copy in all of the arguments */
13469 argvec = make_tree_vec (nargs - ia);
13470 for (i = 0; ia < nargs; ++ia, ++i)
13471 TREE_VEC_ELT (argvec, i) = args[ia];
13473 /* Copy the parameter into parmvec. */
13474 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13475 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13476 /*call_args_p=*/true, /*subr=*/subr))
13479 /* Advance to the end of the list of parameters. */
13480 parms = TREE_CHAIN (parms);
13483 /* Fail if we've reached the end of the parm list, and more args
13484 are present, and the parm list isn't variadic. */
13485 if (ia < nargs && parms == void_list_node)
13487 /* Fail if parms are left and they don't have default values. */
13488 if (parms && parms != void_list_node
13489 && TREE_PURPOSE (parms) == NULL_TREE)
13493 for (i = 0; i < ntparms; i++)
13494 if (!TREE_VEC_ELT (targs, i))
13498 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13501 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13503 /* If this is an undeduced nontype parameter that depends on
13504 a type parameter, try another pass; its type may have been
13505 deduced from a later argument than the one from which
13506 this parameter can be deduced. */
13507 if (TREE_CODE (tparm) == PARM_DECL
13508 && uses_template_parms (TREE_TYPE (tparm))
13509 && !saw_undeduced++)
13512 /* Core issue #226 (C++0x) [temp.deduct]:
13514 If a template argument has not been deduced, its
13515 default template argument, if any, is used.
13517 When we are in C++98 mode, TREE_PURPOSE will either
13518 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13519 to explicitly check cxx_dialect here. */
13520 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13522 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13523 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13524 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13525 arg = convert_template_argument (parm, arg, targs, tf_none,
13527 if (arg == error_mark_node)
13531 TREE_VEC_ELT (targs, i) = arg;
13532 /* The position of the first default template argument,
13533 is also the number of non-defaulted arguments in TARGS.
13535 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13536 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
13541 /* If the type parameter is a parameter pack, then it will
13542 be deduced to an empty parameter pack. */
13543 if (template_parameter_pack_p (tparm))
13547 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13549 arg = make_node (NONTYPE_ARGUMENT_PACK);
13550 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13551 TREE_CONSTANT (arg) = 1;
13554 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13556 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13558 TREE_VEC_ELT (targs, i) = arg;
13564 #ifdef ENABLE_CHECKING
13565 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
13566 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
13572 /* Subroutine of type_unification_real. Args are like the variables
13573 at the call site. ARG is an overloaded function (or template-id);
13574 we try deducing template args from each of the overloads, and if
13575 only one succeeds, we go with that. Modifies TARGS and returns
13576 true on success. */
13579 resolve_overloaded_unification (tree tparms,
13583 unification_kind_t strict,
13586 tree tempargs = copy_node (targs);
13588 tree goodfn = NULL_TREE;
13591 if (TREE_CODE (arg) == ADDR_EXPR)
13593 arg = TREE_OPERAND (arg, 0);
13599 if (TREE_CODE (arg) == COMPONENT_REF)
13600 /* Handle `&x' where `x' is some static or non-static member
13602 arg = TREE_OPERAND (arg, 1);
13604 if (TREE_CODE (arg) == OFFSET_REF)
13605 arg = TREE_OPERAND (arg, 1);
13607 /* Strip baselink information. */
13608 if (BASELINK_P (arg))
13609 arg = BASELINK_FUNCTIONS (arg);
13611 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13613 /* If we got some explicit template args, we need to plug them into
13614 the affected templates before we try to unify, in case the
13615 explicit args will completely resolve the templates in question. */
13617 tree expl_subargs = TREE_OPERAND (arg, 1);
13618 arg = TREE_OPERAND (arg, 0);
13620 for (; arg; arg = OVL_NEXT (arg))
13622 tree fn = OVL_CURRENT (arg);
13623 tree subargs, elem;
13625 if (TREE_CODE (fn) != TEMPLATE_DECL)
13628 ++processing_template_decl;
13629 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13630 expl_subargs, /*check_ret=*/false);
13633 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13634 if (try_one_overload (tparms, targs, tempargs, parm,
13635 elem, strict, sub_strict, addr_p)
13636 && (!goodfn || !decls_match (goodfn, elem)))
13642 --processing_template_decl;
13645 else if (TREE_CODE (arg) != OVERLOAD
13646 && TREE_CODE (arg) != FUNCTION_DECL)
13647 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13648 -- but the deduction does not succeed because the expression is
13649 not just the function on its own. */
13652 for (; arg; arg = OVL_NEXT (arg))
13653 if (try_one_overload (tparms, targs, tempargs, parm,
13654 TREE_TYPE (OVL_CURRENT (arg)),
13655 strict, sub_strict, addr_p)
13656 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13658 goodfn = OVL_CURRENT (arg);
13662 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13663 to function or pointer to member function argument if the set of
13664 overloaded functions does not contain function templates and at most
13665 one of a set of overloaded functions provides a unique match.
13667 So if we found multiple possibilities, we return success but don't
13668 deduce anything. */
13672 int i = TREE_VEC_LENGTH (targs);
13674 if (TREE_VEC_ELT (tempargs, i))
13675 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13683 /* Core DR 115: In contexts where deduction is done and fails, or in
13684 contexts where deduction is not done, if a template argument list is
13685 specified and it, along with any default template arguments, identifies
13686 a single function template specialization, then the template-id is an
13687 lvalue for the function template specialization. */
13690 resolve_nondeduced_context (tree orig_expr)
13692 tree expr, offset, baselink;
13695 if (!type_unknown_p (orig_expr))
13700 offset = NULL_TREE;
13701 baselink = NULL_TREE;
13703 if (TREE_CODE (expr) == ADDR_EXPR)
13705 expr = TREE_OPERAND (expr, 0);
13708 if (TREE_CODE (expr) == OFFSET_REF)
13711 expr = TREE_OPERAND (expr, 1);
13713 if (TREE_CODE (expr) == BASELINK)
13716 expr = BASELINK_FUNCTIONS (expr);
13719 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13722 tree goodfn = NULL_TREE;
13724 /* If we got some explicit template args, we need to plug them into
13725 the affected templates before we try to unify, in case the
13726 explicit args will completely resolve the templates in question. */
13728 tree expl_subargs = TREE_OPERAND (expr, 1);
13729 tree arg = TREE_OPERAND (expr, 0);
13730 tree badfn = NULL_TREE;
13731 tree badargs = NULL_TREE;
13733 for (; arg; arg = OVL_NEXT (arg))
13735 tree fn = OVL_CURRENT (arg);
13736 tree subargs, elem;
13738 if (TREE_CODE (fn) != TEMPLATE_DECL)
13741 ++processing_template_decl;
13742 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13743 expl_subargs, /*check_ret=*/false);
13744 if (subargs && !any_dependent_template_arguments_p (subargs))
13746 elem = instantiate_template (fn, subargs, tf_none);
13747 if (elem == error_mark_node)
13752 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13758 --processing_template_decl;
13764 expr = build_baselink (BASELINK_BINFO (baselink),
13765 BASELINK_ACCESS_BINFO (baselink),
13766 expr, BASELINK_OPTYPE (baselink));
13768 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13769 TREE_OPERAND (offset, 0), expr);
13771 expr = build_address (expr);
13774 else if (good == 0 && badargs)
13775 /* There were no good options and at least one bad one, so let the
13776 user know what the problem is. */
13777 instantiate_template (badfn, badargs, tf_warning_or_error);
13782 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13783 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13784 different overloads deduce different arguments for a given parm.
13785 ADDR_P is true if the expression for which deduction is being
13786 performed was of the form "& fn" rather than simply "fn".
13788 Returns 1 on success. */
13791 try_one_overload (tree tparms,
13796 unification_kind_t strict,
13804 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13805 to function or pointer to member function argument if the set of
13806 overloaded functions does not contain function templates and at most
13807 one of a set of overloaded functions provides a unique match.
13809 So if this is a template, just return success. */
13811 if (uses_template_parms (arg))
13814 if (TREE_CODE (arg) == METHOD_TYPE)
13815 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13817 arg = build_pointer_type (arg);
13819 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13821 /* We don't copy orig_targs for this because if we have already deduced
13822 some template args from previous args, unify would complain when we
13823 try to deduce a template parameter for the same argument, even though
13824 there isn't really a conflict. */
13825 nargs = TREE_VEC_LENGTH (targs);
13826 tempargs = make_tree_vec (nargs);
13828 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13831 /* First make sure we didn't deduce anything that conflicts with
13832 explicitly specified args. */
13833 for (i = nargs; i--; )
13835 tree elt = TREE_VEC_ELT (tempargs, i);
13836 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13840 else if (uses_template_parms (elt))
13841 /* Since we're unifying against ourselves, we will fill in
13842 template args used in the function parm list with our own
13843 template parms. Discard them. */
13844 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13845 else if (oldelt && !template_args_equal (oldelt, elt))
13849 for (i = nargs; i--; )
13851 tree elt = TREE_VEC_ELT (tempargs, i);
13854 TREE_VEC_ELT (targs, i) = elt;
13860 /* PARM is a template class (perhaps with unbound template
13861 parameters). ARG is a fully instantiated type. If ARG can be
13862 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13863 TARGS are as for unify. */
13866 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13868 tree copy_of_targs;
13870 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13871 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13872 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13875 /* We need to make a new template argument vector for the call to
13876 unify. If we used TARGS, we'd clutter it up with the result of
13877 the attempted unification, even if this class didn't work out.
13878 We also don't want to commit ourselves to all the unifications
13879 we've already done, since unification is supposed to be done on
13880 an argument-by-argument basis. In other words, consider the
13881 following pathological case:
13883 template <int I, int J, int K>
13886 template <int I, int J>
13887 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13889 template <int I, int J, int K>
13890 void f(S<I, J, K>, S<I, I, I>);
13899 Now, by the time we consider the unification involving `s2', we
13900 already know that we must have `f<0, 0, 0>'. But, even though
13901 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13902 because there are two ways to unify base classes of S<0, 1, 2>
13903 with S<I, I, I>. If we kept the already deduced knowledge, we
13904 would reject the possibility I=1. */
13905 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13907 /* If unification failed, we're done. */
13908 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13909 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13915 /* Given a template type PARM and a class type ARG, find the unique
13916 base type in ARG that is an instance of PARM. We do not examine
13917 ARG itself; only its base-classes. If there is not exactly one
13918 appropriate base class, return NULL_TREE. PARM may be the type of
13919 a partial specialization, as well as a plain template type. Used
13923 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13925 tree rval = NULL_TREE;
13928 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13930 binfo = TYPE_BINFO (complete_type (arg));
13932 /* The type could not be completed. */
13935 /* Walk in inheritance graph order. The search order is not
13936 important, and this avoids multiple walks of virtual bases. */
13937 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13939 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13943 /* If there is more than one satisfactory baseclass, then:
13947 If they yield more than one possible deduced A, the type
13951 if (rval && !same_type_p (r, rval))
13961 /* Returns the level of DECL, which declares a template parameter. */
13964 template_decl_level (tree decl)
13966 switch (TREE_CODE (decl))
13969 case TEMPLATE_DECL:
13970 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13973 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13976 gcc_unreachable ();
13981 /* Decide whether ARG can be unified with PARM, considering only the
13982 cv-qualifiers of each type, given STRICT as documented for unify.
13983 Returns nonzero iff the unification is OK on that basis. */
13986 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13988 int arg_quals = cp_type_quals (arg);
13989 int parm_quals = cp_type_quals (parm);
13991 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13992 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13994 /* Although a CVR qualifier is ignored when being applied to a
13995 substituted template parameter ([8.3.2]/1 for example), that
13996 does not apply during deduction [14.8.2.4]/1, (even though
13997 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13998 this). Except when we're allowing additional CV qualifiers
13999 at the outer level [14.8.2.1]/3,1st bullet. */
14000 if ((TREE_CODE (arg) == REFERENCE_TYPE
14001 || TREE_CODE (arg) == FUNCTION_TYPE
14002 || TREE_CODE (arg) == METHOD_TYPE)
14003 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
14006 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
14007 && (parm_quals & TYPE_QUAL_RESTRICT))
14011 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
14012 && (arg_quals & parm_quals) != parm_quals)
14015 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
14016 && (parm_quals & arg_quals) != arg_quals)
14022 /* Determines the LEVEL and INDEX for the template parameter PARM. */
14024 template_parm_level_and_index (tree parm, int* level, int* index)
14026 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14027 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14028 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14030 *index = TEMPLATE_TYPE_IDX (parm);
14031 *level = TEMPLATE_TYPE_LEVEL (parm);
14035 *index = TEMPLATE_PARM_IDX (parm);
14036 *level = TEMPLATE_PARM_LEVEL (parm);
14040 /* Unifies the remaining arguments in PACKED_ARGS with the pack
14041 expansion at the end of PACKED_PARMS. Returns 0 if the type
14042 deduction succeeds, 1 otherwise. STRICT is the same as in
14043 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
14044 call argument list. We'll need to adjust the arguments to make them
14045 types. SUBR tells us if this is from a recursive call to
14046 type_unification_real. */
14048 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
14049 tree packed_args, int strict, bool call_args_p,
14053 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
14054 tree pattern = PACK_EXPANSION_PATTERN (parm);
14055 tree pack, packs = NULL_TREE;
14056 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
14057 int len = TREE_VEC_LENGTH (packed_args);
14059 /* Determine the parameter packs we will be deducing from the
14060 pattern, and record their current deductions. */
14061 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
14062 pack; pack = TREE_CHAIN (pack))
14064 tree parm_pack = TREE_VALUE (pack);
14067 /* Determine the index and level of this parameter pack. */
14068 template_parm_level_and_index (parm_pack, &level, &idx);
14070 /* Keep track of the parameter packs and their corresponding
14072 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
14073 TREE_TYPE (packs) = make_tree_vec (len - start);
14076 /* Loop through all of the arguments that have not yet been
14077 unified and unify each with the pattern. */
14078 for (i = start; i < len; i++)
14080 tree parm = pattern;
14082 /* For each parameter pack, clear out the deduced value so that
14083 we can deduce it again. */
14084 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14087 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14089 TMPL_ARG (targs, level, idx) = NULL_TREE;
14092 /* Unify the pattern with the current argument. */
14094 tree arg = TREE_VEC_ELT (packed_args, i);
14095 tree arg_expr = NULL_TREE;
14096 int arg_strict = strict;
14097 bool skip_arg_p = false;
14103 /* This mirrors what we do in type_unification_real. */
14107 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
14108 | UNIFY_ALLOW_MORE_CV_QUAL
14109 | UNIFY_ALLOW_DERIVED);
14113 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
14117 sub_strict = UNIFY_ALLOW_NONE;
14121 gcc_unreachable ();
14126 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
14127 if (type_unknown_p (arg))
14129 /* [temp.deduct.type] A template-argument can be
14130 deduced from a pointer to function or pointer
14131 to member function argument if the set of
14132 overloaded functions does not contain function
14133 templates and at most one of a set of
14134 overloaded functions provides a unique
14137 if (resolve_overloaded_unification
14138 (tparms, targs, parm, arg,
14139 (unification_kind_t) strict,
14149 arg = unlowered_expr_type (arg);
14150 if (arg == error_mark_node)
14155 arg_strict = sub_strict;
14159 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
14160 &parm, &arg, arg_expr);
14165 /* For deduction from an init-list we need the actual list. */
14166 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
14168 if (unify (tparms, targs, parm, arg, arg_strict))
14173 /* For each parameter pack, collect the deduced value. */
14174 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14177 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14179 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
14180 TMPL_ARG (targs, level, idx);
14184 /* Verify that the results of unification with the parameter packs
14185 produce results consistent with what we've seen before, and make
14186 the deduced argument packs available. */
14187 for (pack = packs; pack; pack = TREE_CHAIN (pack))
14189 tree old_pack = TREE_VALUE (pack);
14190 tree new_args = TREE_TYPE (pack);
14191 int i, len = TREE_VEC_LENGTH (new_args);
14193 bool nondeduced_p = false;
14195 /* By default keep the original deduced argument pack.
14196 If necessary, more specific code is going to update the
14197 resulting deduced argument later down in this function. */
14198 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14199 TMPL_ARG (targs, level, idx) = old_pack;
14201 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
14202 actually deduce anything. */
14203 for (i = 0; i < len && !nondeduced_p; ++i)
14204 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
14205 nondeduced_p = true;
14209 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
14211 /* Prepend the explicit arguments onto NEW_ARGS. */
14212 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14213 tree old_args = new_args;
14214 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
14215 int len = explicit_len + TREE_VEC_LENGTH (old_args);
14217 /* Copy the explicit arguments. */
14218 new_args = make_tree_vec (len);
14219 for (i = 0; i < explicit_len; i++)
14220 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
14222 /* Copy the deduced arguments. */
14223 for (; i < len; i++)
14224 TREE_VEC_ELT (new_args, i) =
14225 TREE_VEC_ELT (old_args, i - explicit_len);
14231 /* Build the deduced *_ARGUMENT_PACK. */
14232 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
14234 result = make_node (NONTYPE_ARGUMENT_PACK);
14235 TREE_TYPE (result) =
14236 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
14237 TREE_CONSTANT (result) = 1;
14240 result = cxx_make_type (TYPE_ARGUMENT_PACK);
14242 SET_ARGUMENT_PACK_ARGS (result, new_args);
14244 /* Note the deduced argument packs for this parameter
14246 TMPL_ARG (targs, level, idx) = result;
14248 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
14249 && (ARGUMENT_PACK_ARGS (old_pack)
14250 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
14252 /* We only had the explicitly-provided arguments before, but
14253 now we have a complete set of arguments. */
14254 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
14256 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
14257 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
14258 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
14260 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
14262 /* Inconsistent unification of this parameter pack. */
14269 /* Deduce the value of template parameters. TPARMS is the (innermost)
14270 set of template parameters to a template. TARGS is the bindings
14271 for those template parameters, as determined thus far; TARGS may
14272 include template arguments for outer levels of template parameters
14273 as well. PARM is a parameter to a template function, or a
14274 subcomponent of that parameter; ARG is the corresponding argument.
14275 This function attempts to match PARM with ARG in a manner
14276 consistent with the existing assignments in TARGS. If more values
14277 are deduced, then TARGS is updated.
14279 Returns 0 if the type deduction succeeds, 1 otherwise. The
14280 parameter STRICT is a bitwise or of the following flags:
14283 Require an exact match between PARM and ARG.
14284 UNIFY_ALLOW_MORE_CV_QUAL:
14285 Allow the deduced ARG to be more cv-qualified (by qualification
14286 conversion) than ARG.
14287 UNIFY_ALLOW_LESS_CV_QUAL:
14288 Allow the deduced ARG to be less cv-qualified than ARG.
14289 UNIFY_ALLOW_DERIVED:
14290 Allow the deduced ARG to be a template base class of ARG,
14291 or a pointer to a template base class of the type pointed to by
14293 UNIFY_ALLOW_INTEGER:
14294 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14295 case for more information.
14296 UNIFY_ALLOW_OUTER_LEVEL:
14297 This is the outermost level of a deduction. Used to determine validity
14298 of qualification conversions. A valid qualification conversion must
14299 have const qualified pointers leading up to the inner type which
14300 requires additional CV quals, except at the outer level, where const
14301 is not required [conv.qual]. It would be normal to set this flag in
14302 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14303 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14304 This is the outermost level of a deduction, and PARM can be more CV
14305 qualified at this point.
14306 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14307 This is the outermost level of a deduction, and PARM can be less CV
14308 qualified at this point. */
14311 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14316 int strict_in = strict;
14318 /* I don't think this will do the right thing with respect to types.
14319 But the only case I've seen it in so far has been array bounds, where
14320 signedness is the only information lost, and I think that will be
14322 while (TREE_CODE (parm) == NOP_EXPR)
14323 parm = TREE_OPERAND (parm, 0);
14325 if (arg == error_mark_node)
14327 if (arg == unknown_type_node
14328 || arg == init_list_type_node)
14329 /* We can't deduce anything from this, but we might get all the
14330 template args from other function args. */
14333 /* If PARM uses template parameters, then we can't bail out here,
14334 even if ARG == PARM, since we won't record unifications for the
14335 template parameters. We might need them if we're trying to
14336 figure out which of two things is more specialized. */
14337 if (arg == parm && !uses_template_parms (parm))
14340 /* Handle init lists early, so the rest of the function can assume
14341 we're dealing with a type. */
14342 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14346 tree orig_parm = parm;
14348 /* Replace T with std::initializer_list<T> for deduction. */
14349 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14350 && flag_deduce_init_list)
14351 parm = listify (parm);
14353 if (!is_std_init_list (parm))
14354 /* We can only deduce from an initializer list argument if the
14355 parameter is std::initializer_list; otherwise this is a
14356 non-deduced context. */
14359 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14361 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14363 int elt_strict = strict;
14364 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14366 tree type = TREE_TYPE (elt);
14367 /* It should only be possible to get here for a call. */
14368 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14369 elt_strict |= maybe_adjust_types_for_deduction
14370 (DEDUCE_CALL, &elttype, &type, elt);
14374 if (unify (tparms, targs, elttype, elt, elt_strict))
14378 /* If the std::initializer_list<T> deduction worked, replace the
14379 deduced A with std::initializer_list<A>. */
14380 if (orig_parm != parm)
14382 idx = TEMPLATE_TYPE_IDX (orig_parm);
14383 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14384 targ = listify (targ);
14385 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14390 /* Immediately reject some pairs that won't unify because of
14391 cv-qualification mismatches. */
14392 if (TREE_CODE (arg) == TREE_CODE (parm)
14394 /* It is the elements of the array which hold the cv quals of an array
14395 type, and the elements might be template type parms. We'll check
14396 when we recurse. */
14397 && TREE_CODE (arg) != ARRAY_TYPE
14398 /* We check the cv-qualifiers when unifying with template type
14399 parameters below. We want to allow ARG `const T' to unify with
14400 PARM `T' for example, when computing which of two templates
14401 is more specialized, for example. */
14402 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14403 && !check_cv_quals_for_unify (strict_in, arg, parm))
14406 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14407 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14408 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14409 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14410 strict &= ~UNIFY_ALLOW_DERIVED;
14411 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14412 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14414 switch (TREE_CODE (parm))
14416 case TYPENAME_TYPE:
14418 case UNBOUND_CLASS_TEMPLATE:
14419 /* In a type which contains a nested-name-specifier, template
14420 argument values cannot be deduced for template parameters used
14421 within the nested-name-specifier. */
14424 case TEMPLATE_TYPE_PARM:
14425 case TEMPLATE_TEMPLATE_PARM:
14426 case BOUND_TEMPLATE_TEMPLATE_PARM:
14427 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14428 if (tparm == error_mark_node)
14431 if (TEMPLATE_TYPE_LEVEL (parm)
14432 != template_decl_level (tparm))
14433 /* The PARM is not one we're trying to unify. Just check
14434 to see if it matches ARG. */
14435 return (TREE_CODE (arg) == TREE_CODE (parm)
14436 && same_type_p (parm, arg)) ? 0 : 1;
14437 idx = TEMPLATE_TYPE_IDX (parm);
14438 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14439 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14441 /* Check for mixed types and values. */
14442 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14443 && TREE_CODE (tparm) != TYPE_DECL)
14444 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14445 && TREE_CODE (tparm) != TEMPLATE_DECL))
14448 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14450 /* ARG must be constructed from a template class or a template
14451 template parameter. */
14452 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14453 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14457 tree parmvec = TYPE_TI_ARGS (parm);
14458 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14460 = DECL_INNERMOST_TEMPLATE_PARMS
14461 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14463 int parm_variadic_p = 0;
14465 /* The resolution to DR150 makes clear that default
14466 arguments for an N-argument may not be used to bind T
14467 to a template template parameter with fewer than N
14468 parameters. It is not safe to permit the binding of
14469 default arguments as an extension, as that may change
14470 the meaning of a conforming program. Consider:
14472 struct Dense { static const unsigned int dim = 1; };
14474 template <template <typename> class View,
14476 void operator+(float, View<Block> const&);
14478 template <typename Block,
14479 unsigned int Dim = Block::dim>
14480 struct Lvalue_proxy { operator float() const; };
14484 Lvalue_proxy<Dense> p;
14489 Here, if Lvalue_proxy is permitted to bind to View, then
14490 the global operator+ will be used; if they are not, the
14491 Lvalue_proxy will be converted to float. */
14492 if (coerce_template_parms (parm_parms,
14494 TYPE_TI_TEMPLATE (parm),
14496 /*require_all_args=*/true,
14497 /*use_default_args=*/false)
14498 == error_mark_node)
14501 /* Deduce arguments T, i from TT<T> or TT<i>.
14502 We check each element of PARMVEC and ARGVEC individually
14503 rather than the whole TREE_VEC since they can have
14504 different number of elements. */
14506 parmvec = expand_template_argument_pack (parmvec);
14507 argvec = expand_template_argument_pack (argvec);
14509 len = TREE_VEC_LENGTH (parmvec);
14511 /* Check if the parameters end in a pack, making them
14514 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14515 parm_variadic_p = 1;
14517 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14520 for (i = 0; i < len - parm_variadic_p; ++i)
14522 if (unify (tparms, targs,
14523 TREE_VEC_ELT (parmvec, i),
14524 TREE_VEC_ELT (argvec, i),
14529 if (parm_variadic_p
14530 && unify_pack_expansion (tparms, targs,
14533 /*call_args_p=*/false,
14537 arg = TYPE_TI_TEMPLATE (arg);
14539 /* Fall through to deduce template name. */
14542 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14543 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14545 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14547 /* Simple cases: Value already set, does match or doesn't. */
14548 if (targ != NULL_TREE && template_args_equal (targ, arg))
14555 /* If PARM is `const T' and ARG is only `int', we don't have
14556 a match unless we are allowing additional qualification.
14557 If ARG is `const int' and PARM is just `T' that's OK;
14558 that binds `const int' to `T'. */
14559 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14563 /* Consider the case where ARG is `const volatile int' and
14564 PARM is `const T'. Then, T should be `volatile int'. */
14565 arg = cp_build_qualified_type_real
14566 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14567 if (arg == error_mark_node)
14570 /* Simple cases: Value already set, does match or doesn't. */
14571 if (targ != NULL_TREE && same_type_p (targ, arg))
14576 /* Make sure that ARG is not a variable-sized array. (Note
14577 that were talking about variable-sized arrays (like
14578 `int[n]'), rather than arrays of unknown size (like
14579 `int[]').) We'll get very confused by such a type since
14580 the bound of the array will not be computable in an
14581 instantiation. Besides, such types are not allowed in
14582 ISO C++, so we can do as we please here. */
14583 if (variably_modified_type_p (arg, NULL_TREE))
14586 /* Strip typedefs as in convert_template_argument. */
14587 arg = strip_typedefs (arg);
14590 /* If ARG is a parameter pack or an expansion, we cannot unify
14591 against it unless PARM is also a parameter pack. */
14592 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14593 && !template_parameter_pack_p (parm))
14596 /* If the argument deduction results is a METHOD_TYPE,
14597 then there is a problem.
14598 METHOD_TYPE doesn't map to any real C++ type the result of
14599 the deduction can not be of that type. */
14600 if (TREE_CODE (arg) == METHOD_TYPE)
14603 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14606 case TEMPLATE_PARM_INDEX:
14607 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14608 if (tparm == error_mark_node)
14611 if (TEMPLATE_PARM_LEVEL (parm)
14612 != template_decl_level (tparm))
14613 /* The PARM is not one we're trying to unify. Just check
14614 to see if it matches ARG. */
14615 return !(TREE_CODE (arg) == TREE_CODE (parm)
14616 && cp_tree_equal (parm, arg));
14618 idx = TEMPLATE_PARM_IDX (parm);
14619 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14622 return !cp_tree_equal (targ, arg);
14624 /* [temp.deduct.type] If, in the declaration of a function template
14625 with a non-type template-parameter, the non-type
14626 template-parameter is used in an expression in the function
14627 parameter-list and, if the corresponding template-argument is
14628 deduced, the template-argument type shall match the type of the
14629 template-parameter exactly, except that a template-argument
14630 deduced from an array bound may be of any integral type.
14631 The non-type parameter might use already deduced type parameters. */
14632 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14633 if (!TREE_TYPE (arg))
14634 /* Template-parameter dependent expression. Just accept it for now.
14635 It will later be processed in convert_template_argument. */
14637 else if (same_type_p (TREE_TYPE (arg), tparm))
14639 else if ((strict & UNIFY_ALLOW_INTEGER)
14640 && (TREE_CODE (tparm) == INTEGER_TYPE
14641 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14642 /* Convert the ARG to the type of PARM; the deduced non-type
14643 template argument must exactly match the types of the
14644 corresponding parameter. */
14645 arg = fold (build_nop (tparm, arg));
14646 else if (uses_template_parms (tparm))
14647 /* We haven't deduced the type of this parameter yet. Try again
14653 /* If ARG is a parameter pack or an expansion, we cannot unify
14654 against it unless PARM is also a parameter pack. */
14655 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14656 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14659 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14664 /* A pointer-to-member constant can be unified only with
14665 another constant. */
14666 if (TREE_CODE (arg) != PTRMEM_CST)
14669 /* Just unify the class member. It would be useless (and possibly
14670 wrong, depending on the strict flags) to unify also
14671 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14672 arg refer to the same variable, even if through different
14673 classes. For instance:
14675 struct A { int x; };
14678 Unification of &A::x and &B::x must succeed. */
14679 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14680 PTRMEM_CST_MEMBER (arg), strict);
14685 if (TREE_CODE (arg) != POINTER_TYPE)
14688 /* [temp.deduct.call]
14690 A can be another pointer or pointer to member type that can
14691 be converted to the deduced A via a qualification
14692 conversion (_conv.qual_).
14694 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14695 This will allow for additional cv-qualification of the
14696 pointed-to types if appropriate. */
14698 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14699 /* The derived-to-base conversion only persists through one
14700 level of pointers. */
14701 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14703 return unify (tparms, targs, TREE_TYPE (parm),
14704 TREE_TYPE (arg), strict);
14707 case REFERENCE_TYPE:
14708 if (TREE_CODE (arg) != REFERENCE_TYPE)
14710 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14711 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14714 if (TREE_CODE (arg) != ARRAY_TYPE)
14716 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14717 != (TYPE_DOMAIN (arg) == NULL_TREE))
14719 if (TYPE_DOMAIN (parm) != NULL_TREE)
14726 /* Our representation of array types uses "N - 1" as the
14727 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14728 not an integer constant. We cannot unify arbitrarily
14729 complex expressions, so we eliminate the MINUS_EXPRs
14731 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14732 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14735 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14736 parm_max = TREE_OPERAND (parm_max, 0);
14738 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14739 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14742 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14743 trying to unify the type of a variable with the type
14744 of a template parameter. For example:
14746 template <unsigned int N>
14747 void f (char (&) [N]);
14754 Here, the type of the ARG will be "int [g(i)]", and
14755 may be a SAVE_EXPR, etc. */
14756 if (TREE_CODE (arg_max) != MINUS_EXPR)
14758 arg_max = TREE_OPERAND (arg_max, 0);
14761 /* If only one of the bounds used a MINUS_EXPR, compensate
14762 by adding one to the other bound. */
14763 if (parm_cst && !arg_cst)
14764 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14768 else if (arg_cst && !parm_cst)
14769 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14774 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14777 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14778 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14785 case ENUMERAL_TYPE:
14787 if (TREE_CODE (arg) != TREE_CODE (parm))
14790 /* We have already checked cv-qualification at the top of the
14792 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14795 /* As far as unification is concerned, this wins. Later checks
14796 will invalidate it if necessary. */
14799 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14800 /* Type INTEGER_CST can come from ordinary constant template args. */
14802 while (TREE_CODE (arg) == NOP_EXPR)
14803 arg = TREE_OPERAND (arg, 0);
14805 if (TREE_CODE (arg) != INTEGER_CST)
14807 return !tree_int_cst_equal (parm, arg);
14812 if (TREE_CODE (arg) != TREE_VEC)
14814 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14816 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14817 if (unify (tparms, targs,
14818 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14826 if (TREE_CODE (arg) != TREE_CODE (parm))
14829 if (TYPE_PTRMEMFUNC_P (parm))
14831 if (!TYPE_PTRMEMFUNC_P (arg))
14834 return unify (tparms, targs,
14835 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14836 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14840 if (CLASSTYPE_TEMPLATE_INFO (parm))
14842 tree t = NULL_TREE;
14844 if (strict_in & UNIFY_ALLOW_DERIVED)
14846 /* First, we try to unify the PARM and ARG directly. */
14847 t = try_class_unification (tparms, targs,
14852 /* Fallback to the special case allowed in
14853 [temp.deduct.call]:
14855 If P is a class, and P has the form
14856 template-id, then A can be a derived class of
14857 the deduced A. Likewise, if P is a pointer to
14858 a class of the form template-id, A can be a
14859 pointer to a derived class pointed to by the
14861 t = get_template_base (tparms, targs, parm, arg);
14867 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14868 && (CLASSTYPE_TI_TEMPLATE (parm)
14869 == CLASSTYPE_TI_TEMPLATE (arg)))
14870 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14871 Then, we should unify `int' and `U'. */
14874 /* There's no chance of unification succeeding. */
14877 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14878 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14880 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14885 case FUNCTION_TYPE:
14887 unsigned int nargs;
14892 if (TREE_CODE (arg) != TREE_CODE (parm))
14895 /* CV qualifications for methods can never be deduced, they must
14896 match exactly. We need to check them explicitly here,
14897 because type_unification_real treats them as any other
14898 cv-qualified parameter. */
14899 if (TREE_CODE (parm) == METHOD_TYPE
14900 && (!check_cv_quals_for_unify
14902 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14903 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14906 if (unify (tparms, targs, TREE_TYPE (parm),
14907 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14910 nargs = list_length (TYPE_ARG_TYPES (arg));
14911 args = XALLOCAVEC (tree, nargs);
14912 for (a = TYPE_ARG_TYPES (arg), i = 0;
14913 a != NULL_TREE && a != void_list_node;
14914 a = TREE_CHAIN (a), ++i)
14915 args[i] = TREE_VALUE (a);
14918 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14919 args, nargs, 1, DEDUCE_EXACT,
14924 /* Unify a pointer to member with a pointer to member function, which
14925 deduces the type of the member as a function type. */
14926 if (TYPE_PTRMEMFUNC_P (arg))
14930 cp_cv_quals cv_quals;
14932 /* Check top-level cv qualifiers */
14933 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14936 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14937 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14940 /* Determine the type of the function we are unifying against. */
14941 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14943 build_function_type (TREE_TYPE (method_type),
14944 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14946 /* Extract the cv-qualifiers of the member function from the
14947 implicit object parameter and place them on the function
14948 type to be restored later. */
14950 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14951 fntype = build_qualified_type (fntype, cv_quals);
14952 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14955 if (TREE_CODE (arg) != OFFSET_TYPE)
14957 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14958 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14960 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14964 if (DECL_TEMPLATE_PARM_P (parm))
14965 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14966 if (arg != integral_constant_value (parm))
14971 case TEMPLATE_DECL:
14972 /* Matched cases are handled by the ARG == PARM test above. */
14975 case TYPE_ARGUMENT_PACK:
14976 case NONTYPE_ARGUMENT_PACK:
14978 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14979 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14980 int i, len = TREE_VEC_LENGTH (packed_parms);
14981 int argslen = TREE_VEC_LENGTH (packed_args);
14982 int parm_variadic_p = 0;
14984 for (i = 0; i < len; ++i)
14986 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14989 /* We can unify against something with a trailing
14991 parm_variadic_p = 1;
14993 /* Since there is something following the pack
14994 expansion, we cannot unify this template argument
15001 /* If we don't have enough arguments to satisfy the parameters
15002 (not counting the pack expression at the end), or we have
15003 too many arguments for a parameter list that doesn't end in
15004 a pack expression, we can't unify. */
15005 if (argslen < (len - parm_variadic_p)
15006 || (argslen > len && !parm_variadic_p))
15009 /* Unify all of the parameters that precede the (optional)
15010 pack expression. */
15011 for (i = 0; i < len - parm_variadic_p; ++i)
15013 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
15014 TREE_VEC_ELT (packed_args, i), strict))
15018 if (parm_variadic_p)
15019 return unify_pack_expansion (tparms, targs,
15020 packed_parms, packed_args,
15021 strict, /*call_args_p=*/false,
15029 case DECLTYPE_TYPE:
15030 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
15035 /* Unification fails if we hit an error node. */
15039 gcc_assert (EXPR_P (parm));
15041 /* We must be looking at an expression. This can happen with
15045 void foo(S<I>, S<I + 2>);
15047 This is a "nondeduced context":
15051 The nondeduced contexts are:
15053 --A type that is a template-id in which one or more of
15054 the template-arguments is an expression that references
15055 a template-parameter.
15057 In these cases, we assume deduction succeeded, but don't
15058 actually infer any unifications. */
15060 if (!uses_template_parms (parm)
15061 && !template_args_equal (parm, arg))
15068 /* Note that DECL can be defined in this translation unit, if
15072 mark_definable (tree decl)
15075 DECL_NOT_REALLY_EXTERN (decl) = 1;
15076 FOR_EACH_CLONE (clone, decl)
15077 DECL_NOT_REALLY_EXTERN (clone) = 1;
15080 /* Called if RESULT is explicitly instantiated, or is a member of an
15081 explicitly instantiated class. */
15084 mark_decl_instantiated (tree result, int extern_p)
15086 SET_DECL_EXPLICIT_INSTANTIATION (result);
15088 /* If this entity has already been written out, it's too late to
15089 make any modifications. */
15090 if (TREE_ASM_WRITTEN (result))
15093 if (TREE_CODE (result) != FUNCTION_DECL)
15094 /* The TREE_PUBLIC flag for function declarations will have been
15095 set correctly by tsubst. */
15096 TREE_PUBLIC (result) = 1;
15098 /* This might have been set by an earlier implicit instantiation. */
15099 DECL_COMDAT (result) = 0;
15102 DECL_NOT_REALLY_EXTERN (result) = 0;
15105 mark_definable (result);
15106 /* Always make artificials weak. */
15107 if (DECL_ARTIFICIAL (result) && flag_weak)
15108 comdat_linkage (result);
15109 /* For WIN32 we also want to put explicit instantiations in
15110 linkonce sections. */
15111 else if (TREE_PUBLIC (result))
15112 maybe_make_one_only (result);
15115 /* If EXTERN_P, then this function will not be emitted -- unless
15116 followed by an explicit instantiation, at which point its linkage
15117 will be adjusted. If !EXTERN_P, then this function will be
15118 emitted here. In neither circumstance do we want
15119 import_export_decl to adjust the linkage. */
15120 DECL_INTERFACE_KNOWN (result) = 1;
15123 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
15124 important template arguments. If any are missing, we check whether
15125 they're important by using error_mark_node for substituting into any
15126 args that were used for partial ordering (the ones between ARGS and END)
15127 and seeing if it bubbles up. */
15130 check_undeduced_parms (tree targs, tree args, tree end)
15132 bool found = false;
15134 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
15135 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
15138 TREE_VEC_ELT (targs, i) = error_mark_node;
15142 for (; args != end; args = TREE_CHAIN (args))
15144 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
15145 if (substed == error_mark_node)
15152 /* Given two function templates PAT1 and PAT2, return:
15154 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
15155 -1 if PAT2 is more specialized than PAT1.
15156 0 if neither is more specialized.
15158 LEN indicates the number of parameters we should consider
15159 (defaulted parameters should not be considered).
15161 The 1998 std underspecified function template partial ordering, and
15162 DR214 addresses the issue. We take pairs of arguments, one from
15163 each of the templates, and deduce them against each other. One of
15164 the templates will be more specialized if all the *other*
15165 template's arguments deduce against its arguments and at least one
15166 of its arguments *does* *not* deduce against the other template's
15167 corresponding argument. Deduction is done as for class templates.
15168 The arguments used in deduction have reference and top level cv
15169 qualifiers removed. Iff both arguments were originally reference
15170 types *and* deduction succeeds in both directions, the template
15171 with the more cv-qualified argument wins for that pairing (if
15172 neither is more cv-qualified, they both are equal). Unlike regular
15173 deduction, after all the arguments have been deduced in this way,
15174 we do *not* verify the deduced template argument values can be
15175 substituted into non-deduced contexts.
15177 The logic can be a bit confusing here, because we look at deduce1 and
15178 targs1 to see if pat2 is at least as specialized, and vice versa; if we
15179 can find template arguments for pat1 to make arg1 look like arg2, that
15180 means that arg2 is at least as specialized as arg1. */
15183 more_specialized_fn (tree pat1, tree pat2, int len)
15185 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
15186 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
15187 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
15188 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
15189 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
15190 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
15191 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
15192 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
15193 tree origs1, origs2;
15194 bool lose1 = false;
15195 bool lose2 = false;
15197 /* Remove the this parameter from non-static member functions. If
15198 one is a non-static member function and the other is not a static
15199 member function, remove the first parameter from that function
15200 also. This situation occurs for operator functions where we
15201 locate both a member function (with this pointer) and non-member
15202 operator (with explicit first operand). */
15203 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
15205 len--; /* LEN is the number of significant arguments for DECL1 */
15206 args1 = TREE_CHAIN (args1);
15207 if (!DECL_STATIC_FUNCTION_P (decl2))
15208 args2 = TREE_CHAIN (args2);
15210 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
15212 args2 = TREE_CHAIN (args2);
15213 if (!DECL_STATIC_FUNCTION_P (decl1))
15216 args1 = TREE_CHAIN (args1);
15220 /* If only one is a conversion operator, they are unordered. */
15221 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
15224 /* Consider the return type for a conversion function */
15225 if (DECL_CONV_FN_P (decl1))
15227 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
15228 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
15232 processing_template_decl++;
15238 /* Stop when an ellipsis is seen. */
15239 && args1 != NULL_TREE && args2 != NULL_TREE)
15241 tree arg1 = TREE_VALUE (args1);
15242 tree arg2 = TREE_VALUE (args2);
15243 int deduce1, deduce2;
15247 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15248 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15250 /* When both arguments are pack expansions, we need only
15251 unify the patterns themselves. */
15252 arg1 = PACK_EXPANSION_PATTERN (arg1);
15253 arg2 = PACK_EXPANSION_PATTERN (arg2);
15255 /* This is the last comparison we need to do. */
15259 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15261 arg1 = TREE_TYPE (arg1);
15262 quals1 = cp_type_quals (arg1);
15265 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15267 arg2 = TREE_TYPE (arg2);
15268 quals2 = cp_type_quals (arg2);
15271 if ((quals1 < 0) != (quals2 < 0))
15273 /* Only of the args is a reference, see if we should apply
15274 array/function pointer decay to it. This is not part of
15275 DR214, but is, IMHO, consistent with the deduction rules
15276 for the function call itself, and with our earlier
15277 implementation of the underspecified partial ordering
15278 rules. (nathan). */
15281 switch (TREE_CODE (arg1))
15284 arg1 = TREE_TYPE (arg1);
15286 case FUNCTION_TYPE:
15287 arg1 = build_pointer_type (arg1);
15296 switch (TREE_CODE (arg2))
15299 arg2 = TREE_TYPE (arg2);
15301 case FUNCTION_TYPE:
15302 arg2 = build_pointer_type (arg2);
15311 arg1 = TYPE_MAIN_VARIANT (arg1);
15312 arg2 = TYPE_MAIN_VARIANT (arg2);
15314 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15316 int i, len2 = list_length (args2);
15317 tree parmvec = make_tree_vec (1);
15318 tree argvec = make_tree_vec (len2);
15321 /* Setup the parameter vector, which contains only ARG1. */
15322 TREE_VEC_ELT (parmvec, 0) = arg1;
15324 /* Setup the argument vector, which contains the remaining
15326 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15327 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15329 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15330 argvec, UNIFY_ALLOW_NONE,
15331 /*call_args_p=*/false,
15334 /* We cannot deduce in the other direction, because ARG1 is
15335 a pack expansion but ARG2 is not. */
15338 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15340 int i, len1 = list_length (args1);
15341 tree parmvec = make_tree_vec (1);
15342 tree argvec = make_tree_vec (len1);
15345 /* Setup the parameter vector, which contains only ARG1. */
15346 TREE_VEC_ELT (parmvec, 0) = arg2;
15348 /* Setup the argument vector, which contains the remaining
15350 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15351 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15353 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15354 argvec, UNIFY_ALLOW_NONE,
15355 /*call_args_p=*/false,
15358 /* We cannot deduce in the other direction, because ARG2 is
15359 a pack expansion but ARG1 is not.*/
15365 /* The normal case, where neither argument is a pack
15367 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15368 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15371 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15372 arg2, then arg2 is not as specialized as arg1. */
15378 /* "If, for a given type, deduction succeeds in both directions
15379 (i.e., the types are identical after the transformations above)
15380 and if the type from the argument template is more cv-qualified
15381 than the type from the parameter template (as described above)
15382 that type is considered to be more specialized than the other. If
15383 neither type is more cv-qualified than the other then neither type
15384 is more specialized than the other."
15386 We check same_type_p explicitly because deduction can also succeed
15387 in both directions when there is a nondeduced context. */
15388 if (deduce1 && deduce2
15389 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0
15390 && same_type_p (arg1, arg2))
15392 if ((quals1 & quals2) == quals2)
15394 if ((quals1 & quals2) == quals1)
15398 if (lose1 && lose2)
15399 /* We've failed to deduce something in either direction.
15400 These must be unordered. */
15403 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15404 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15405 /* We have already processed all of the arguments in our
15406 handing of the pack expansion type. */
15409 args1 = TREE_CHAIN (args1);
15410 args2 = TREE_CHAIN (args2);
15413 /* "In most cases, all template parameters must have values in order for
15414 deduction to succeed, but for partial ordering purposes a template
15415 parameter may remain without a value provided it is not used in the
15416 types being used for partial ordering."
15418 Thus, if we are missing any of the targs1 we need to substitute into
15419 origs1, then pat2 is not as specialized as pat1. This can happen when
15420 there is a nondeduced context. */
15421 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15423 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15426 processing_template_decl--;
15428 /* All things being equal, if the next argument is a pack expansion
15429 for one function but not for the other, prefer the
15430 non-variadic function. FIXME this is bogus; see c++/41958. */
15432 && args1 && TREE_VALUE (args1)
15433 && args2 && TREE_VALUE (args2))
15435 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
15436 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
15439 if (lose1 == lose2)
15447 /* Determine which of two partial specializations is more specialized.
15449 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15450 to the first partial specialization. The TREE_VALUE is the
15451 innermost set of template parameters for the partial
15452 specialization. PAT2 is similar, but for the second template.
15454 Return 1 if the first partial specialization is more specialized;
15455 -1 if the second is more specialized; 0 if neither is more
15458 See [temp.class.order] for information about determining which of
15459 two templates is more specialized. */
15462 more_specialized_class (tree pat1, tree pat2)
15467 bool any_deductions = false;
15469 tmpl1 = TREE_TYPE (pat1);
15470 tmpl2 = TREE_TYPE (pat2);
15472 /* Just like what happens for functions, if we are ordering between
15473 different class template specializations, we may encounter dependent
15474 types in the arguments, and we need our dependency check functions
15475 to behave correctly. */
15476 ++processing_template_decl;
15477 targs = get_class_bindings (TREE_VALUE (pat1),
15478 CLASSTYPE_TI_ARGS (tmpl1),
15479 CLASSTYPE_TI_ARGS (tmpl2));
15483 any_deductions = true;
15486 targs = get_class_bindings (TREE_VALUE (pat2),
15487 CLASSTYPE_TI_ARGS (tmpl2),
15488 CLASSTYPE_TI_ARGS (tmpl1));
15492 any_deductions = true;
15494 --processing_template_decl;
15496 /* In the case of a tie where at least one of the class templates
15497 has a parameter pack at the end, the template with the most
15498 non-packed parameters wins. */
15501 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15502 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15504 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15505 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15506 int len1 = TREE_VEC_LENGTH (args1);
15507 int len2 = TREE_VEC_LENGTH (args2);
15509 /* We don't count the pack expansion at the end. */
15510 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15512 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15517 else if (len1 < len2)
15524 /* Return the template arguments that will produce the function signature
15525 DECL from the function template FN, with the explicit template
15526 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15527 also match. Return NULL_TREE if no satisfactory arguments could be
15531 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15533 int ntparms = DECL_NTPARMS (fn);
15534 tree targs = make_tree_vec (ntparms);
15536 tree decl_arg_types;
15538 unsigned int nargs, ix;
15541 /* Substitute the explicit template arguments into the type of DECL.
15542 The call to fn_type_unification will handle substitution into the
15544 decl_type = TREE_TYPE (decl);
15545 if (explicit_args && uses_template_parms (decl_type))
15548 tree converted_args;
15550 if (DECL_TEMPLATE_INFO (decl))
15551 tmpl = DECL_TI_TEMPLATE (decl);
15553 /* We can get here for some invalid specializations. */
15557 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15558 explicit_args, NULL_TREE,
15560 /*require_all_args=*/false,
15561 /*use_default_args=*/false);
15562 if (converted_args == error_mark_node)
15565 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15566 if (decl_type == error_mark_node)
15570 /* Never do unification on the 'this' parameter. */
15571 decl_arg_types = skip_artificial_parms_for (decl,
15572 TYPE_ARG_TYPES (decl_type));
15574 nargs = list_length (decl_arg_types);
15575 args = XALLOCAVEC (tree, nargs);
15576 for (arg = decl_arg_types, ix = 0;
15577 arg != NULL_TREE && arg != void_list_node;
15578 arg = TREE_CHAIN (arg), ++ix)
15579 args[ix] = TREE_VALUE (arg);
15581 if (fn_type_unification (fn, explicit_args, targs,
15583 (check_rettype || DECL_CONV_FN_P (fn)
15584 ? TREE_TYPE (decl_type) : NULL_TREE),
15585 DEDUCE_EXACT, LOOKUP_NORMAL))
15591 /* Return the innermost template arguments that, when applied to a
15592 template specialization whose innermost template parameters are
15593 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15596 For example, suppose we have:
15598 template <class T, class U> struct S {};
15599 template <class T> struct S<T*, int> {};
15601 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15602 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15603 int}. The resulting vector will be {double}, indicating that `T'
15604 is bound to `double'. */
15607 get_class_bindings (tree tparms, tree spec_args, tree args)
15609 int i, ntparms = TREE_VEC_LENGTH (tparms);
15611 tree innermost_deduced_args;
15613 innermost_deduced_args = make_tree_vec (ntparms);
15614 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15616 deduced_args = copy_node (args);
15617 SET_TMPL_ARGS_LEVEL (deduced_args,
15618 TMPL_ARGS_DEPTH (deduced_args),
15619 innermost_deduced_args);
15622 deduced_args = innermost_deduced_args;
15624 if (unify (tparms, deduced_args,
15625 INNERMOST_TEMPLATE_ARGS (spec_args),
15626 INNERMOST_TEMPLATE_ARGS (args),
15630 for (i = 0; i < ntparms; ++i)
15631 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15634 /* Verify that nondeduced template arguments agree with the type
15635 obtained from argument deduction.
15639 struct A { typedef int X; };
15640 template <class T, class U> struct C {};
15641 template <class T> struct C<T, typename T::X> {};
15643 Then with the instantiation `C<A, int>', we can deduce that
15644 `T' is `A' but unify () does not check whether `typename T::X'
15646 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15647 if (spec_args == error_mark_node
15648 /* We only need to check the innermost arguments; the other
15649 arguments will always agree. */
15650 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15651 INNERMOST_TEMPLATE_ARGS (args)))
15654 /* Now that we have bindings for all of the template arguments,
15655 ensure that the arguments deduced for the template template
15656 parameters have compatible template parameter lists. See the use
15657 of template_template_parm_bindings_ok_p in fn_type_unification
15658 for more information. */
15659 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15662 return deduced_args;
15665 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15666 Return the TREE_LIST node with the most specialized template, if
15667 any. If there is no most specialized template, the error_mark_node
15670 Note that this function does not look at, or modify, the
15671 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15672 returned is one of the elements of INSTANTIATIONS, callers may
15673 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15674 and retrieve it from the value returned. */
15677 most_specialized_instantiation (tree templates)
15681 ++processing_template_decl;
15684 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15688 if (get_bindings (TREE_VALUE (champ),
15689 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15690 NULL_TREE, /*check_ret=*/false))
15693 if (get_bindings (TREE_VALUE (fn),
15694 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15695 NULL_TREE, /*check_ret=*/false))
15702 /* Equally specialized, move to next function. If there
15703 is no next function, nothing's most specialized. */
15704 fn = TREE_CHAIN (fn);
15712 /* Now verify that champ is better than everything earlier in the
15713 instantiation list. */
15714 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15715 if (get_bindings (TREE_VALUE (champ),
15716 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15717 NULL_TREE, /*check_ret=*/false)
15718 || !get_bindings (TREE_VALUE (fn),
15719 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15720 NULL_TREE, /*check_ret=*/false))
15726 processing_template_decl--;
15729 return error_mark_node;
15734 /* If DECL is a specialization of some template, return the most
15735 general such template. Otherwise, returns NULL_TREE.
15737 For example, given:
15739 template <class T> struct S { template <class U> void f(U); };
15741 if TMPL is `template <class U> void S<int>::f(U)' this will return
15742 the full template. This function will not trace past partial
15743 specializations, however. For example, given in addition:
15745 template <class T> struct S<T*> { template <class U> void f(U); };
15747 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15748 `template <class T> template <class U> S<T*>::f(U)'. */
15751 most_general_template (tree decl)
15753 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15754 an immediate specialization. */
15755 if (TREE_CODE (decl) == FUNCTION_DECL)
15757 if (DECL_TEMPLATE_INFO (decl)) {
15758 decl = DECL_TI_TEMPLATE (decl);
15760 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15761 template friend. */
15762 if (TREE_CODE (decl) != TEMPLATE_DECL)
15768 /* Look for more and more general templates. */
15769 while (DECL_TEMPLATE_INFO (decl))
15771 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15772 (See cp-tree.h for details.) */
15773 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15776 if (CLASS_TYPE_P (TREE_TYPE (decl))
15777 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15780 /* Stop if we run into an explicitly specialized class template. */
15781 if (!DECL_NAMESPACE_SCOPE_P (decl)
15782 && DECL_CONTEXT (decl)
15783 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15786 decl = DECL_TI_TEMPLATE (decl);
15792 /* Return the most specialized of the class template partial
15793 specializations of TMPL which can produce TYPE, a specialization of
15794 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15795 a _TYPE node corresponding to the partial specialization, while the
15796 TREE_PURPOSE is the set of template arguments that must be
15797 substituted into the TREE_TYPE in order to generate TYPE.
15799 If the choice of partial specialization is ambiguous, a diagnostic
15800 is issued, and the error_mark_node is returned. If there are no
15801 partial specializations of TMPL matching TYPE, then NULL_TREE is
15805 most_specialized_class (tree type, tree tmpl)
15807 tree list = NULL_TREE;
15813 tree outer_args = NULL_TREE;
15815 tmpl = most_general_template (tmpl);
15816 args = CLASSTYPE_TI_ARGS (type);
15818 /* For determining which partial specialization to use, only the
15819 innermost args are interesting. */
15820 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15822 outer_args = strip_innermost_template_args (args, 1);
15823 args = INNERMOST_TEMPLATE_ARGS (args);
15826 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15828 tree partial_spec_args;
15830 tree parms = TREE_VALUE (t);
15832 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15837 ++processing_template_decl;
15839 /* Discard the outer levels of args, and then substitute in the
15840 template args from the enclosing class. */
15841 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15842 partial_spec_args = tsubst_template_args
15843 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15845 /* PARMS already refers to just the innermost parms, but the
15846 template parms in partial_spec_args had their levels lowered
15847 by tsubst, so we need to do the same for the parm list. We
15848 can't just tsubst the TREE_VEC itself, as tsubst wants to
15849 treat a TREE_VEC as an argument vector. */
15850 parms = copy_node (parms);
15851 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15852 TREE_VEC_ELT (parms, i) =
15853 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15855 --processing_template_decl;
15857 spec_args = get_class_bindings (parms,
15863 spec_args = add_to_template_args (outer_args, spec_args);
15864 list = tree_cons (spec_args, TREE_VALUE (t), list);
15865 TREE_TYPE (list) = TREE_TYPE (t);
15872 ambiguous_p = false;
15875 t = TREE_CHAIN (t);
15876 for (; t; t = TREE_CHAIN (t))
15878 fate = more_specialized_class (champ, t);
15885 t = TREE_CHAIN (t);
15888 ambiguous_p = true;
15897 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15899 fate = more_specialized_class (champ, t);
15902 ambiguous_p = true;
15910 char *spaces = NULL;
15911 error ("ambiguous class template instantiation for %q#T", type);
15912 str = TREE_CHAIN (list) ? _("candidates are:") : _("candidate is:");
15913 for (t = list; t; t = TREE_CHAIN (t))
15915 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
15916 spaces = spaces ? spaces : get_spaces (str);
15919 return error_mark_node;
15925 /* Explicitly instantiate DECL. */
15928 do_decl_instantiation (tree decl, tree storage)
15930 tree result = NULL_TREE;
15933 if (!decl || decl == error_mark_node)
15934 /* An error occurred, for which grokdeclarator has already issued
15935 an appropriate message. */
15937 else if (! DECL_LANG_SPECIFIC (decl))
15939 error ("explicit instantiation of non-template %q#D", decl);
15942 else if (TREE_CODE (decl) == VAR_DECL)
15944 /* There is an asymmetry here in the way VAR_DECLs and
15945 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15946 the latter, the DECL we get back will be marked as a
15947 template instantiation, and the appropriate
15948 DECL_TEMPLATE_INFO will be set up. This does not happen for
15949 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15950 should handle VAR_DECLs as it currently handles
15952 if (!DECL_CLASS_SCOPE_P (decl))
15954 error ("%qD is not a static data member of a class template", decl);
15957 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15958 if (!result || TREE_CODE (result) != VAR_DECL)
15960 error ("no matching template for %qD found", decl);
15963 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15965 error ("type %qT for explicit instantiation %qD does not match "
15966 "declared type %qT", TREE_TYPE (result), decl,
15971 else if (TREE_CODE (decl) != FUNCTION_DECL)
15973 error ("explicit instantiation of %q#D", decl);
15979 /* Check for various error cases. Note that if the explicit
15980 instantiation is valid the RESULT will currently be marked as an
15981 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15982 until we get here. */
15984 if (DECL_TEMPLATE_SPECIALIZATION (result))
15986 /* DR 259 [temp.spec].
15988 Both an explicit instantiation and a declaration of an explicit
15989 specialization shall not appear in a program unless the explicit
15990 instantiation follows a declaration of the explicit specialization.
15992 For a given set of template parameters, if an explicit
15993 instantiation of a template appears after a declaration of an
15994 explicit specialization for that template, the explicit
15995 instantiation has no effect. */
15998 else if (DECL_EXPLICIT_INSTANTIATION (result))
16002 No program shall explicitly instantiate any template more
16005 We check DECL_NOT_REALLY_EXTERN so as not to complain when
16006 the first instantiation was `extern' and the second is not,
16007 and EXTERN_P for the opposite case. */
16008 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
16009 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
16010 /* If an "extern" explicit instantiation follows an ordinary
16011 explicit instantiation, the template is instantiated. */
16015 else if (!DECL_IMPLICIT_INSTANTIATION (result))
16017 error ("no matching template for %qD found", result);
16020 else if (!DECL_TEMPLATE_INFO (result))
16022 permerror (input_location, "explicit instantiation of non-template %q#D", result);
16026 if (storage == NULL_TREE)
16028 else if (storage == ridpointers[(int) RID_EXTERN])
16030 if (!in_system_header && (cxx_dialect == cxx98))
16031 pedwarn (input_location, OPT_pedantic,
16032 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
16037 error ("storage class %qD applied to template instantiation", storage);
16039 check_explicit_instantiation_namespace (result);
16040 mark_decl_instantiated (result, extern_p);
16042 instantiate_decl (result, /*defer_ok=*/1,
16043 /*expl_inst_class_mem_p=*/false);
16047 mark_class_instantiated (tree t, int extern_p)
16049 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
16050 SET_CLASSTYPE_INTERFACE_KNOWN (t);
16051 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
16052 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
16055 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
16056 rest_of_type_compilation (t, 1);
16060 /* Called from do_type_instantiation through binding_table_foreach to
16061 do recursive instantiation for the type bound in ENTRY. */
16063 bt_instantiate_type_proc (binding_entry entry, void *data)
16065 tree storage = *(tree *) data;
16067 if (MAYBE_CLASS_TYPE_P (entry->type)
16068 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
16069 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
16072 /* Called from do_type_instantiation to instantiate a member
16073 (a member function or a static member variable) of an
16074 explicitly instantiated class template. */
16076 instantiate_class_member (tree decl, int extern_p)
16078 mark_decl_instantiated (decl, extern_p);
16080 instantiate_decl (decl, /*defer_ok=*/1,
16081 /*expl_inst_class_mem_p=*/true);
16084 /* Perform an explicit instantiation of template class T. STORAGE, if
16085 non-null, is the RID for extern, inline or static. COMPLAIN is
16086 nonzero if this is called from the parser, zero if called recursively,
16087 since the standard is unclear (as detailed below). */
16090 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
16095 int previous_instantiation_extern_p = 0;
16097 if (TREE_CODE (t) == TYPE_DECL)
16100 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
16102 error ("explicit instantiation of non-template type %qT", t);
16108 if (!COMPLETE_TYPE_P (t))
16110 if (complain & tf_error)
16111 error ("explicit instantiation of %q#T before definition of template",
16116 if (storage != NULL_TREE)
16118 if (!in_system_header)
16120 if (storage == ridpointers[(int) RID_EXTERN])
16122 if (cxx_dialect == cxx98)
16123 pedwarn (input_location, OPT_pedantic,
16124 "ISO C++ 1998 forbids the use of %<extern%> on "
16125 "explicit instantiations");
16128 pedwarn (input_location, OPT_pedantic,
16129 "ISO C++ forbids the use of %qE"
16130 " on explicit instantiations", storage);
16133 if (storage == ridpointers[(int) RID_INLINE])
16135 else if (storage == ridpointers[(int) RID_EXTERN])
16137 else if (storage == ridpointers[(int) RID_STATIC])
16141 error ("storage class %qD applied to template instantiation",
16147 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
16149 /* DR 259 [temp.spec].
16151 Both an explicit instantiation and a declaration of an explicit
16152 specialization shall not appear in a program unless the explicit
16153 instantiation follows a declaration of the explicit specialization.
16155 For a given set of template parameters, if an explicit
16156 instantiation of a template appears after a declaration of an
16157 explicit specialization for that template, the explicit
16158 instantiation has no effect. */
16161 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
16165 No program shall explicitly instantiate any template more
16168 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
16169 instantiation was `extern'. If EXTERN_P then the second is.
16170 These cases are OK. */
16171 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
16173 if (!previous_instantiation_extern_p && !extern_p
16174 && (complain & tf_error))
16175 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
16177 /* If we've already instantiated the template, just return now. */
16178 if (!CLASSTYPE_INTERFACE_ONLY (t))
16182 check_explicit_instantiation_namespace (TYPE_NAME (t));
16183 mark_class_instantiated (t, extern_p);
16191 /* In contrast to implicit instantiation, where only the
16192 declarations, and not the definitions, of members are
16193 instantiated, we have here:
16197 The explicit instantiation of a class template specialization
16198 implies the instantiation of all of its members not
16199 previously explicitly specialized in the translation unit
16200 containing the explicit instantiation.
16202 Of course, we can't instantiate member template classes, since
16203 we don't have any arguments for them. Note that the standard
16204 is unclear on whether the instantiation of the members are
16205 *explicit* instantiations or not. However, the most natural
16206 interpretation is that it should be an explicit instantiation. */
16209 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
16210 if (TREE_CODE (tmp) == FUNCTION_DECL
16211 && DECL_TEMPLATE_INSTANTIATION (tmp))
16212 instantiate_class_member (tmp, extern_p);
16214 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
16215 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
16216 instantiate_class_member (tmp, extern_p);
16218 if (CLASSTYPE_NESTED_UTDS (t))
16219 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
16220 bt_instantiate_type_proc, &storage);
16224 /* Given a function DECL, which is a specialization of TMPL, modify
16225 DECL to be a re-instantiation of TMPL with the same template
16226 arguments. TMPL should be the template into which tsubst'ing
16227 should occur for DECL, not the most general template.
16229 One reason for doing this is a scenario like this:
16232 void f(const T&, int i);
16234 void g() { f(3, 7); }
16237 void f(const T& t, const int i) { }
16239 Note that when the template is first instantiated, with
16240 instantiate_template, the resulting DECL will have no name for the
16241 first parameter, and the wrong type for the second. So, when we go
16242 to instantiate the DECL, we regenerate it. */
16245 regenerate_decl_from_template (tree decl, tree tmpl)
16247 /* The arguments used to instantiate DECL, from the most general
16252 args = DECL_TI_ARGS (decl);
16253 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
16255 /* Make sure that we can see identifiers, and compute access
16257 push_access_scope (decl);
16259 if (TREE_CODE (decl) == FUNCTION_DECL)
16267 args_depth = TMPL_ARGS_DEPTH (args);
16268 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16269 if (args_depth > parms_depth)
16270 args = get_innermost_template_args (args, parms_depth);
16272 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16273 args, tf_error, NULL_TREE);
16275 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16278 /* Merge parameter declarations. */
16279 decl_parm = skip_artificial_parms_for (decl,
16280 DECL_ARGUMENTS (decl));
16282 = skip_artificial_parms_for (code_pattern,
16283 DECL_ARGUMENTS (code_pattern));
16284 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16289 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16290 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16291 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16293 parm_type = type_decays_to (parm_type);
16294 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16295 TREE_TYPE (decl_parm) = parm_type;
16296 attributes = DECL_ATTRIBUTES (pattern_parm);
16297 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16299 DECL_ATTRIBUTES (decl_parm) = attributes;
16300 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16302 decl_parm = TREE_CHAIN (decl_parm);
16303 pattern_parm = TREE_CHAIN (pattern_parm);
16305 /* Merge any parameters that match with the function parameter
16307 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16310 tree expanded_types;
16311 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16312 the parameters in this function parameter pack. */
16313 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16314 args, tf_error, NULL_TREE);
16315 len = TREE_VEC_LENGTH (expanded_types);
16316 for (i = 0; i < len; i++)
16321 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16322 /* Rename the parameter to include the index. */
16323 DECL_NAME (decl_parm) =
16324 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16325 parm_type = TREE_VEC_ELT (expanded_types, i);
16326 parm_type = type_decays_to (parm_type);
16327 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16328 TREE_TYPE (decl_parm) = parm_type;
16329 attributes = DECL_ATTRIBUTES (pattern_parm);
16330 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16332 DECL_ATTRIBUTES (decl_parm) = attributes;
16333 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16335 decl_parm = TREE_CHAIN (decl_parm);
16338 /* Merge additional specifiers from the CODE_PATTERN. */
16339 if (DECL_DECLARED_INLINE_P (code_pattern)
16340 && !DECL_DECLARED_INLINE_P (decl))
16341 DECL_DECLARED_INLINE_P (decl) = 1;
16343 else if (TREE_CODE (decl) == VAR_DECL)
16344 DECL_INITIAL (decl) =
16345 tsubst_expr (DECL_INITIAL (code_pattern), args,
16346 tf_error, DECL_TI_TEMPLATE (decl),
16347 /*integral_constant_expression_p=*/false);
16349 gcc_unreachable ();
16351 pop_access_scope (decl);
16354 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16355 substituted to get DECL. */
16358 template_for_substitution (tree decl)
16360 tree tmpl = DECL_TI_TEMPLATE (decl);
16362 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16363 for the instantiation. This is not always the most general
16364 template. Consider, for example:
16367 struct S { template <class U> void f();
16368 template <> void f<int>(); };
16370 and an instantiation of S<double>::f<int>. We want TD to be the
16371 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16372 while (/* An instantiation cannot have a definition, so we need a
16373 more general template. */
16374 DECL_TEMPLATE_INSTANTIATION (tmpl)
16375 /* We must also deal with friend templates. Given:
16377 template <class T> struct S {
16378 template <class U> friend void f() {};
16381 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16382 so far as the language is concerned, but that's still
16383 where we get the pattern for the instantiation from. On
16384 other hand, if the definition comes outside the class, say:
16386 template <class T> struct S {
16387 template <class U> friend void f();
16389 template <class U> friend void f() {}
16391 we don't need to look any further. That's what the check for
16392 DECL_INITIAL is for. */
16393 || (TREE_CODE (decl) == FUNCTION_DECL
16394 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16395 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16397 /* The present template, TD, should not be a definition. If it
16398 were a definition, we should be using it! Note that we
16399 cannot restructure the loop to just keep going until we find
16400 a template with a definition, since that might go too far if
16401 a specialization was declared, but not defined. */
16402 gcc_assert (TREE_CODE (decl) != VAR_DECL
16403 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16405 /* Fetch the more general template. */
16406 tmpl = DECL_TI_TEMPLATE (tmpl);
16412 /* Returns true if we need to instantiate this template instance even if we
16413 know we aren't going to emit it.. */
16416 always_instantiate_p (tree decl)
16418 /* We always instantiate inline functions so that we can inline them. An
16419 explicit instantiation declaration prohibits implicit instantiation of
16420 non-inline functions. With high levels of optimization, we would
16421 normally inline non-inline functions -- but we're not allowed to do
16422 that for "extern template" functions. Therefore, we check
16423 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16424 return ((TREE_CODE (decl) == FUNCTION_DECL
16425 && DECL_DECLARED_INLINE_P (decl))
16426 /* And we need to instantiate static data members so that
16427 their initializers are available in integral constant
16429 || (TREE_CODE (decl) == VAR_DECL
16430 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16433 /* Produce the definition of D, a _DECL generated from a template. If
16434 DEFER_OK is nonzero, then we don't have to actually do the
16435 instantiation now; we just have to do it sometime. Normally it is
16436 an error if this is an explicit instantiation but D is undefined.
16437 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16438 explicitly instantiated class template. */
16441 instantiate_decl (tree d, int defer_ok,
16442 bool expl_inst_class_mem_p)
16444 tree tmpl = DECL_TI_TEMPLATE (d);
16451 bool pattern_defined;
16453 location_t saved_loc = input_location;
16456 /* This function should only be used to instantiate templates for
16457 functions and static member variables. */
16458 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16459 || TREE_CODE (d) == VAR_DECL);
16461 /* Variables are never deferred; if instantiation is required, they
16462 are instantiated right away. That allows for better code in the
16463 case that an expression refers to the value of the variable --
16464 if the variable has a constant value the referring expression can
16465 take advantage of that fact. */
16466 if (TREE_CODE (d) == VAR_DECL)
16469 /* Don't instantiate cloned functions. Instead, instantiate the
16470 functions they cloned. */
16471 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16472 d = DECL_CLONED_FUNCTION (d);
16474 if (DECL_TEMPLATE_INSTANTIATED (d)
16475 || DECL_TEMPLATE_SPECIALIZATION (d))
16476 /* D has already been instantiated or explicitly specialized, so
16477 there's nothing for us to do here.
16479 It might seem reasonable to check whether or not D is an explicit
16480 instantiation, and, if so, stop here. But when an explicit
16481 instantiation is deferred until the end of the compilation,
16482 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16483 the instantiation. */
16486 /* Check to see whether we know that this template will be
16487 instantiated in some other file, as with "extern template"
16489 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16491 /* In general, we do not instantiate such templates. */
16492 if (external_p && !always_instantiate_p (d))
16495 gen_tmpl = most_general_template (tmpl);
16496 gen_args = DECL_TI_ARGS (d);
16498 if (tmpl != gen_tmpl)
16499 /* We should already have the extra args. */
16500 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16501 == TMPL_ARGS_DEPTH (gen_args));
16502 /* And what's in the hash table should match D. */
16503 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16504 || spec == NULL_TREE);
16506 /* This needs to happen before any tsubsting. */
16507 if (! push_tinst_level (d))
16510 timevar_push (TV_PARSE);
16512 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16513 for the instantiation. */
16514 td = template_for_substitution (d);
16515 code_pattern = DECL_TEMPLATE_RESULT (td);
16517 /* We should never be trying to instantiate a member of a class
16518 template or partial specialization. */
16519 gcc_assert (d != code_pattern);
16521 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16522 || DECL_TEMPLATE_SPECIALIZATION (td))
16523 /* In the case of a friend template whose definition is provided
16524 outside the class, we may have too many arguments. Drop the
16525 ones we don't need. The same is true for specializations. */
16526 args = get_innermost_template_args
16527 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16531 if (TREE_CODE (d) == FUNCTION_DECL)
16532 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16534 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16536 /* We may be in the middle of deferred access check. Disable it now. */
16537 push_deferring_access_checks (dk_no_deferred);
16539 /* Unless an explicit instantiation directive has already determined
16540 the linkage of D, remember that a definition is available for
16542 if (pattern_defined
16543 && !DECL_INTERFACE_KNOWN (d)
16544 && !DECL_NOT_REALLY_EXTERN (d))
16545 mark_definable (d);
16547 input_location = DECL_SOURCE_LOCATION (d);
16549 /* If D is a member of an explicitly instantiated class template,
16550 and no definition is available, treat it like an implicit
16552 if (!pattern_defined && expl_inst_class_mem_p
16553 && DECL_EXPLICIT_INSTANTIATION (d))
16555 DECL_NOT_REALLY_EXTERN (d) = 0;
16556 DECL_INTERFACE_KNOWN (d) = 0;
16557 SET_DECL_IMPLICIT_INSTANTIATION (d);
16560 /* Recheck the substitutions to obtain any warning messages
16561 about ignoring cv qualifiers. Don't do this for artificial decls,
16562 as it breaks the context-sensitive substitution for lambda op(). */
16563 if (!defer_ok && !DECL_ARTIFICIAL (d))
16565 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16566 tree type = TREE_TYPE (gen);
16568 /* Make sure that we can see identifiers, and compute access
16569 correctly. D is already the target FUNCTION_DECL with the
16571 push_access_scope (d);
16573 if (TREE_CODE (gen) == FUNCTION_DECL)
16575 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16576 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16578 /* Don't simply tsubst the function type, as that will give
16579 duplicate warnings about poor parameter qualifications.
16580 The function arguments are the same as the decl_arguments
16581 without the top level cv qualifiers. */
16582 type = TREE_TYPE (type);
16584 tsubst (type, gen_args, tf_warning_or_error, d);
16586 pop_access_scope (d);
16589 /* Defer all other templates, unless we have been explicitly
16590 forbidden from doing so. */
16591 if (/* If there is no definition, we cannot instantiate the
16594 /* If it's OK to postpone instantiation, do so. */
16596 /* If this is a static data member that will be defined
16597 elsewhere, we don't want to instantiate the entire data
16598 member, but we do want to instantiate the initializer so that
16599 we can substitute that elsewhere. */
16600 || (external_p && TREE_CODE (d) == VAR_DECL))
16602 /* The definition of the static data member is now required so
16603 we must substitute the initializer. */
16604 if (TREE_CODE (d) == VAR_DECL
16605 && !DECL_INITIAL (d)
16606 && DECL_INITIAL (code_pattern))
16611 ns = decl_namespace_context (d);
16612 push_nested_namespace (ns);
16613 push_nested_class (DECL_CONTEXT (d));
16614 init = tsubst_expr (DECL_INITIAL (code_pattern),
16616 tf_warning_or_error, NULL_TREE,
16617 /*integral_constant_expression_p=*/false);
16618 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16619 /*asmspec_tree=*/NULL_TREE,
16620 LOOKUP_ONLYCONVERTING);
16621 pop_nested_class ();
16622 pop_nested_namespace (ns);
16625 /* We restore the source position here because it's used by
16626 add_pending_template. */
16627 input_location = saved_loc;
16629 if (at_eof && !pattern_defined
16630 && DECL_EXPLICIT_INSTANTIATION (d)
16631 && DECL_NOT_REALLY_EXTERN (d))
16634 The definition of a non-exported function template, a
16635 non-exported member function template, or a non-exported
16636 member function or static data member of a class template
16637 shall be present in every translation unit in which it is
16638 explicitly instantiated. */
16639 permerror (input_location, "explicit instantiation of %qD "
16640 "but no definition available", d);
16642 /* ??? Historically, we have instantiated inline functions, even
16643 when marked as "extern template". */
16644 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16645 add_pending_template (d);
16648 /* Tell the repository that D is available in this translation unit
16649 -- and see if it is supposed to be instantiated here. */
16650 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16652 /* In a PCH file, despite the fact that the repository hasn't
16653 requested instantiation in the PCH it is still possible that
16654 an instantiation will be required in a file that includes the
16657 add_pending_template (d);
16658 /* Instantiate inline functions so that the inliner can do its
16659 job, even though we'll not be emitting a copy of this
16661 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16665 need_push = !cfun || !global_bindings_p ();
16667 push_to_top_level ();
16669 /* Mark D as instantiated so that recursive calls to
16670 instantiate_decl do not try to instantiate it again. */
16671 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16673 /* Regenerate the declaration in case the template has been modified
16674 by a subsequent redeclaration. */
16675 regenerate_decl_from_template (d, td);
16677 /* We already set the file and line above. Reset them now in case
16678 they changed as a result of calling regenerate_decl_from_template. */
16679 input_location = DECL_SOURCE_LOCATION (d);
16681 if (TREE_CODE (d) == VAR_DECL)
16685 /* Clear out DECL_RTL; whatever was there before may not be right
16686 since we've reset the type of the declaration. */
16687 SET_DECL_RTL (d, NULL_RTX);
16688 DECL_IN_AGGR_P (d) = 0;
16690 /* The initializer is placed in DECL_INITIAL by
16691 regenerate_decl_from_template. Pull it out so that
16692 cp_finish_decl can process it. */
16693 init = DECL_INITIAL (d);
16694 DECL_INITIAL (d) = NULL_TREE;
16695 DECL_INITIALIZED_P (d) = 0;
16697 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16698 initializer. That function will defer actual emission until
16699 we have a chance to determine linkage. */
16700 DECL_EXTERNAL (d) = 0;
16702 /* Enter the scope of D so that access-checking works correctly. */
16703 push_nested_class (DECL_CONTEXT (d));
16704 cp_finish_decl (d, init, false, NULL_TREE, 0);
16705 pop_nested_class ();
16707 else if (TREE_CODE (d) == FUNCTION_DECL)
16709 htab_t saved_local_specializations;
16714 /* Save away the current list, in case we are instantiating one
16715 template from within the body of another. */
16716 saved_local_specializations = local_specializations;
16718 /* Set up the list of local specializations. */
16719 local_specializations = htab_create (37,
16720 hash_local_specialization,
16721 eq_local_specializations,
16724 /* Set up context. */
16725 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16727 /* Create substitution entries for the parameters. */
16728 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16729 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16730 spec_parm = DECL_ARGUMENTS (d);
16731 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16733 register_local_specialization (spec_parm, tmpl_parm);
16734 spec_parm = skip_artificial_parms_for (d, spec_parm);
16735 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16737 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16739 register_local_specialization (spec_parm, tmpl_parm);
16740 tmpl_parm = TREE_CHAIN (tmpl_parm);
16741 spec_parm = TREE_CHAIN (spec_parm);
16743 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16745 /* Register the (value) argument pack as a specialization of
16746 TMPL_PARM, then move on. */
16747 tree argpack = make_fnparm_pack (spec_parm);
16748 register_local_specialization (argpack, tmpl_parm);
16749 tmpl_parm = TREE_CHAIN (tmpl_parm);
16750 spec_parm = NULL_TREE;
16752 gcc_assert (!spec_parm);
16754 /* Substitute into the body of the function. */
16755 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16756 tf_warning_or_error, tmpl,
16757 /*integral_constant_expression_p=*/false);
16759 /* Set the current input_location to the end of the function
16760 so that finish_function knows where we are. */
16761 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
16763 /* We don't need the local specializations any more. */
16764 htab_delete (local_specializations);
16765 local_specializations = saved_local_specializations;
16767 /* Finish the function. */
16768 d = finish_function (0);
16769 expand_or_defer_fn (d);
16772 /* We're not deferring instantiation any more. */
16773 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16776 pop_from_top_level ();
16779 input_location = saved_loc;
16780 pop_deferring_access_checks ();
16781 pop_tinst_level ();
16783 timevar_pop (TV_PARSE);
16788 /* Run through the list of templates that we wish we could
16789 instantiate, and instantiate any we can. RETRIES is the
16790 number of times we retry pending template instantiation. */
16793 instantiate_pending_templates (int retries)
16796 location_t saved_loc = input_location;
16798 /* Instantiating templates may trigger vtable generation. This in turn
16799 may require further template instantiations. We place a limit here
16800 to avoid infinite loop. */
16801 if (pending_templates && retries >= max_tinst_depth)
16803 tree decl = pending_templates->tinst->decl;
16805 error ("template instantiation depth exceeds maximum of %d"
16806 " instantiating %q+D, possibly from virtual table generation"
16807 " (use -ftemplate-depth-NN to increase the maximum)",
16808 max_tinst_depth, decl);
16809 if (TREE_CODE (decl) == FUNCTION_DECL)
16810 /* Pretend that we defined it. */
16811 DECL_INITIAL (decl) = error_mark_node;
16817 struct pending_template **t = &pending_templates;
16818 struct pending_template *last = NULL;
16822 tree instantiation = reopen_tinst_level ((*t)->tinst);
16823 bool complete = false;
16825 if (TYPE_P (instantiation))
16829 if (!COMPLETE_TYPE_P (instantiation))
16831 instantiate_class_template (instantiation);
16832 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16833 for (fn = TYPE_METHODS (instantiation);
16835 fn = TREE_CHAIN (fn))
16836 if (! DECL_ARTIFICIAL (fn))
16837 instantiate_decl (fn,
16839 /*expl_inst_class_mem_p=*/false);
16840 if (COMPLETE_TYPE_P (instantiation))
16844 complete = COMPLETE_TYPE_P (instantiation);
16848 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16849 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16852 = instantiate_decl (instantiation,
16854 /*expl_inst_class_mem_p=*/false);
16855 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16859 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16860 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16864 /* If INSTANTIATION has been instantiated, then we don't
16865 need to consider it again in the future. */
16873 current_tinst_level = NULL;
16875 last_pending_template = last;
16877 while (reconsider);
16879 input_location = saved_loc;
16882 /* Substitute ARGVEC into T, which is a list of initializers for
16883 either base class or a non-static data member. The TREE_PURPOSEs
16884 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16885 instantiate_decl. */
16888 tsubst_initializer_list (tree t, tree argvec)
16890 tree inits = NULL_TREE;
16892 for (; t; t = TREE_CHAIN (t))
16896 tree expanded_bases = NULL_TREE;
16897 tree expanded_arguments = NULL_TREE;
16900 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16905 /* Expand the base class expansion type into separate base
16907 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16908 tf_warning_or_error,
16910 if (expanded_bases == error_mark_node)
16913 /* We'll be building separate TREE_LISTs of arguments for
16915 len = TREE_VEC_LENGTH (expanded_bases);
16916 expanded_arguments = make_tree_vec (len);
16917 for (i = 0; i < len; i++)
16918 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16920 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16921 expand each argument in the TREE_VALUE of t. */
16922 expr = make_node (EXPR_PACK_EXPANSION);
16923 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16924 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16926 if (TREE_VALUE (t) == void_type_node)
16927 /* VOID_TYPE_NODE is used to indicate
16928 value-initialization. */
16930 for (i = 0; i < len; i++)
16931 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16935 /* Substitute parameter packs into each argument in the
16937 in_base_initializer = 1;
16938 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16940 tree expanded_exprs;
16942 /* Expand the argument. */
16943 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16945 = tsubst_pack_expansion (expr, argvec,
16946 tf_warning_or_error,
16948 if (expanded_exprs == error_mark_node)
16951 /* Prepend each of the expanded expressions to the
16952 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16953 for (i = 0; i < len; i++)
16955 TREE_VEC_ELT (expanded_arguments, i) =
16956 tree_cons (NULL_TREE,
16957 TREE_VEC_ELT (expanded_exprs, i),
16958 TREE_VEC_ELT (expanded_arguments, i));
16961 in_base_initializer = 0;
16963 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16964 since we built them backwards. */
16965 for (i = 0; i < len; i++)
16967 TREE_VEC_ELT (expanded_arguments, i) =
16968 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16973 for (i = 0; i < len; ++i)
16975 if (expanded_bases)
16977 decl = TREE_VEC_ELT (expanded_bases, i);
16978 decl = expand_member_init (decl);
16979 init = TREE_VEC_ELT (expanded_arguments, i);
16983 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16984 tf_warning_or_error, NULL_TREE);
16986 decl = expand_member_init (decl);
16987 if (decl && !DECL_P (decl))
16988 in_base_initializer = 1;
16990 init = tsubst_expr (TREE_VALUE (t), argvec,
16991 tf_warning_or_error, NULL_TREE,
16992 /*integral_constant_expression_p=*/false);
16993 in_base_initializer = 0;
16998 init = build_tree_list (decl, init);
16999 TREE_CHAIN (init) = inits;
17007 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
17010 set_current_access_from_decl (tree decl)
17012 if (TREE_PRIVATE (decl))
17013 current_access_specifier = access_private_node;
17014 else if (TREE_PROTECTED (decl))
17015 current_access_specifier = access_protected_node;
17017 current_access_specifier = access_public_node;
17020 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
17021 is the instantiation (which should have been created with
17022 start_enum) and ARGS are the template arguments to use. */
17025 tsubst_enum (tree tag, tree newtag, tree args)
17029 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
17034 decl = TREE_VALUE (e);
17035 /* Note that in a template enum, the TREE_VALUE is the
17036 CONST_DECL, not the corresponding INTEGER_CST. */
17037 value = tsubst_expr (DECL_INITIAL (decl),
17038 args, tf_warning_or_error, NULL_TREE,
17039 /*integral_constant_expression_p=*/true);
17041 /* Give this enumeration constant the correct access. */
17042 set_current_access_from_decl (decl);
17044 /* Actually build the enumerator itself. */
17045 build_enumerator (DECL_NAME (decl), value, newtag);
17048 finish_enum (newtag);
17049 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
17050 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
17053 /* DECL is a FUNCTION_DECL that is a template specialization. Return
17054 its type -- but without substituting the innermost set of template
17055 arguments. So, innermost set of template parameters will appear in
17059 get_mostly_instantiated_function_type (tree decl)
17067 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
17068 targs = DECL_TI_ARGS (decl);
17069 tparms = DECL_TEMPLATE_PARMS (tmpl);
17070 parm_depth = TMPL_PARMS_DEPTH (tparms);
17072 /* There should be as many levels of arguments as there are levels
17074 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
17076 fn_type = TREE_TYPE (tmpl);
17078 if (parm_depth == 1)
17079 /* No substitution is necessary. */
17083 int i, save_access_control;
17086 /* Replace the innermost level of the TARGS with NULL_TREEs to
17087 let tsubst know not to substitute for those parameters. */
17088 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
17089 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
17090 SET_TMPL_ARGS_LEVEL (partial_args, i,
17091 TMPL_ARGS_LEVEL (targs, i));
17092 SET_TMPL_ARGS_LEVEL (partial_args,
17093 TMPL_ARGS_DEPTH (targs),
17094 make_tree_vec (DECL_NTPARMS (tmpl)));
17096 /* Disable access control as this function is used only during
17098 save_access_control = flag_access_control;
17099 flag_access_control = 0;
17101 ++processing_template_decl;
17102 /* Now, do the (partial) substitution to figure out the
17103 appropriate function type. */
17104 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
17105 --processing_template_decl;
17107 /* Substitute into the template parameters to obtain the real
17108 innermost set of parameters. This step is important if the
17109 innermost set of template parameters contains value
17110 parameters whose types depend on outer template parameters. */
17111 TREE_VEC_LENGTH (partial_args)--;
17112 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
17114 flag_access_control = save_access_control;
17120 /* Return truthvalue if we're processing a template different from
17121 the last one involved in diagnostics. */
17123 problematic_instantiation_changed (void)
17125 return last_template_error_tick != tinst_level_tick;
17128 /* Remember current template involved in diagnostics. */
17130 record_last_problematic_instantiation (void)
17132 last_template_error_tick = tinst_level_tick;
17135 struct tinst_level *
17136 current_instantiation (void)
17138 return current_tinst_level;
17141 /* [temp.param] Check that template non-type parm TYPE is of an allowable
17142 type. Return zero for ok, nonzero for disallowed. Issue error and
17143 warning messages under control of COMPLAIN. */
17146 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
17148 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
17150 else if (POINTER_TYPE_P (type))
17152 else if (TYPE_PTR_TO_MEMBER_P (type))
17154 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
17156 else if (TREE_CODE (type) == TYPENAME_TYPE)
17159 if (complain & tf_error)
17160 error ("%q#T is not a valid type for a template constant parameter", type);
17164 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
17165 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
17168 dependent_type_p_r (tree type)
17174 A type is dependent if it is:
17176 -- a template parameter. Template template parameters are types
17177 for us (since TYPE_P holds true for them) so we handle
17179 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17180 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
17182 /* -- a qualified-id with a nested-name-specifier which contains a
17183 class-name that names a dependent type or whose unqualified-id
17184 names a dependent type. */
17185 if (TREE_CODE (type) == TYPENAME_TYPE)
17187 /* -- a cv-qualified type where the cv-unqualified type is
17189 type = TYPE_MAIN_VARIANT (type);
17190 /* -- a compound type constructed from any dependent type. */
17191 if (TYPE_PTR_TO_MEMBER_P (type))
17192 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
17193 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
17195 else if (TREE_CODE (type) == POINTER_TYPE
17196 || TREE_CODE (type) == REFERENCE_TYPE)
17197 return dependent_type_p (TREE_TYPE (type));
17198 else if (TREE_CODE (type) == FUNCTION_TYPE
17199 || TREE_CODE (type) == METHOD_TYPE)
17203 if (dependent_type_p (TREE_TYPE (type)))
17205 for (arg_type = TYPE_ARG_TYPES (type);
17207 arg_type = TREE_CHAIN (arg_type))
17208 if (dependent_type_p (TREE_VALUE (arg_type)))
17212 /* -- an array type constructed from any dependent type or whose
17213 size is specified by a constant expression that is
17214 value-dependent. */
17215 if (TREE_CODE (type) == ARRAY_TYPE)
17217 if (TYPE_DOMAIN (type)
17218 && dependent_type_p (TYPE_DOMAIN (type)))
17220 return dependent_type_p (TREE_TYPE (type));
17222 else if (TREE_CODE (type) == INTEGER_TYPE
17223 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
17225 /* If this is the TYPE_DOMAIN of an array type, consider it
17226 dependent. We already checked for value-dependence in
17227 compute_array_index_type. */
17228 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
17231 /* -- a template-id in which either the template name is a template
17233 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
17235 /* ... or any of the template arguments is a dependent type or
17236 an expression that is type-dependent or value-dependent. */
17237 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
17238 && (any_dependent_template_arguments_p
17239 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
17242 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
17243 argument of the `typeof' expression is not type-dependent, then
17244 it should already been have resolved. */
17245 if (TREE_CODE (type) == TYPEOF_TYPE
17246 || TREE_CODE (type) == DECLTYPE_TYPE)
17249 /* A template argument pack is dependent if any of its packed
17251 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
17253 tree args = ARGUMENT_PACK_ARGS (type);
17254 int i, len = TREE_VEC_LENGTH (args);
17255 for (i = 0; i < len; ++i)
17256 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17260 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17261 be template parameters. */
17262 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17265 /* The standard does not specifically mention types that are local
17266 to template functions or local classes, but they should be
17267 considered dependent too. For example:
17269 template <int I> void f() {
17274 The size of `E' cannot be known until the value of `I' has been
17275 determined. Therefore, `E' must be considered dependent. */
17276 scope = TYPE_CONTEXT (type);
17277 if (scope && TYPE_P (scope))
17278 return dependent_type_p (scope);
17279 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17280 return type_dependent_expression_p (scope);
17282 /* Other types are non-dependent. */
17286 /* Returns TRUE if TYPE is dependent, in the sense of
17287 [temp.dep.type]. */
17290 dependent_type_p (tree type)
17292 /* If there are no template parameters in scope, then there can't be
17293 any dependent types. */
17294 if (!processing_template_decl)
17296 /* If we are not processing a template, then nobody should be
17297 providing us with a dependent type. */
17299 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17303 /* If the type is NULL, we have not computed a type for the entity
17304 in question; in that case, the type is dependent. */
17308 /* Erroneous types can be considered non-dependent. */
17309 if (type == error_mark_node)
17312 /* If we have not already computed the appropriate value for TYPE,
17314 if (!TYPE_DEPENDENT_P_VALID (type))
17316 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17317 TYPE_DEPENDENT_P_VALID (type) = 1;
17320 return TYPE_DEPENDENT_P (type);
17323 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17324 lookup. In other words, a dependent type that is not the current
17328 dependent_scope_p (tree scope)
17330 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17331 && !currently_open_class (scope));
17334 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
17337 dependent_scope_ref_p (tree expression, bool criterion (tree))
17342 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
17344 if (!TYPE_P (TREE_OPERAND (expression, 0)))
17347 scope = TREE_OPERAND (expression, 0);
17348 name = TREE_OPERAND (expression, 1);
17352 An id-expression is type-dependent if it contains a
17353 nested-name-specifier that contains a class-name that names a
17355 /* The suggested resolution to Core Issue 224 implies that if the
17356 qualifying type is the current class, then we must peek
17359 && currently_open_class (scope)
17360 && !criterion (name))
17362 if (dependent_type_p (scope))
17368 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17369 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17373 value_dependent_expression_p (tree expression)
17375 if (!processing_template_decl)
17378 /* A name declared with a dependent type. */
17379 if (DECL_P (expression) && type_dependent_expression_p (expression))
17382 switch (TREE_CODE (expression))
17384 case IDENTIFIER_NODE:
17385 /* A name that has not been looked up -- must be dependent. */
17388 case TEMPLATE_PARM_INDEX:
17389 /* A non-type template parm. */
17393 /* A non-type template parm. */
17394 if (DECL_TEMPLATE_PARM_P (expression))
17396 return value_dependent_expression_p (DECL_INITIAL (expression));
17399 /* A constant with integral or enumeration type and is initialized
17400 with an expression that is value-dependent. */
17401 if (DECL_INITIAL (expression)
17402 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17403 && value_dependent_expression_p (DECL_INITIAL (expression)))
17407 case DYNAMIC_CAST_EXPR:
17408 case STATIC_CAST_EXPR:
17409 case CONST_CAST_EXPR:
17410 case REINTERPRET_CAST_EXPR:
17412 /* These expressions are value-dependent if the type to which
17413 the cast occurs is dependent or the expression being casted
17414 is value-dependent. */
17416 tree type = TREE_TYPE (expression);
17418 if (dependent_type_p (type))
17421 /* A functional cast has a list of operands. */
17422 expression = TREE_OPERAND (expression, 0);
17425 /* If there are no operands, it must be an expression such
17426 as "int()". This should not happen for aggregate types
17427 because it would form non-constant expressions. */
17428 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17433 if (TREE_CODE (expression) == TREE_LIST)
17434 return any_value_dependent_elements_p (expression);
17436 return value_dependent_expression_p (expression);
17441 /* A `sizeof' expression is value-dependent if the operand is
17442 type-dependent or is a pack expansion. */
17443 expression = TREE_OPERAND (expression, 0);
17444 if (PACK_EXPANSION_P (expression))
17446 else if (TYPE_P (expression))
17447 return dependent_type_p (expression);
17448 return type_dependent_expression_p (expression);
17451 return dependent_scope_ref_p (expression, value_dependent_expression_p);
17453 case COMPONENT_REF:
17454 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17455 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17458 /* A CALL_EXPR may appear in a constant expression if it is a
17459 call to a builtin function, e.g., __builtin_constant_p. All
17460 such calls are value-dependent. */
17463 case NONTYPE_ARGUMENT_PACK:
17464 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17465 is value-dependent. */
17467 tree values = ARGUMENT_PACK_ARGS (expression);
17468 int i, len = TREE_VEC_LENGTH (values);
17470 for (i = 0; i < len; ++i)
17471 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17479 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17480 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17481 || (type2 ? dependent_type_p (type2) : false));
17485 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17486 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17489 /* A constant expression is value-dependent if any subexpression is
17490 value-dependent. */
17491 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17493 case tcc_reference:
17495 return (value_dependent_expression_p
17496 (TREE_OPERAND (expression, 0)));
17498 case tcc_comparison:
17500 return ((value_dependent_expression_p
17501 (TREE_OPERAND (expression, 0)))
17502 || (value_dependent_expression_p
17503 (TREE_OPERAND (expression, 1))));
17505 case tcc_expression:
17509 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17510 /* In some cases, some of the operands may be missing.
17511 (For example, in the case of PREDECREMENT_EXPR, the
17512 amount to increment by may be missing.) That doesn't
17513 make the expression dependent. */
17514 if (TREE_OPERAND (expression, i)
17515 && (value_dependent_expression_p
17516 (TREE_OPERAND (expression, i))))
17526 /* The expression is not value-dependent. */
17530 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17531 [temp.dep.expr]. */
17534 type_dependent_expression_p (tree expression)
17536 if (!processing_template_decl)
17539 if (expression == error_mark_node)
17542 /* An unresolved name is always dependent. */
17543 if (TREE_CODE (expression) == IDENTIFIER_NODE
17544 || TREE_CODE (expression) == USING_DECL)
17547 /* Some expression forms are never type-dependent. */
17548 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17549 || TREE_CODE (expression) == SIZEOF_EXPR
17550 || TREE_CODE (expression) == ALIGNOF_EXPR
17551 || TREE_CODE (expression) == TRAIT_EXPR
17552 || TREE_CODE (expression) == TYPEID_EXPR
17553 || TREE_CODE (expression) == DELETE_EXPR
17554 || TREE_CODE (expression) == VEC_DELETE_EXPR
17555 || TREE_CODE (expression) == THROW_EXPR)
17558 /* The types of these expressions depends only on the type to which
17559 the cast occurs. */
17560 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17561 || TREE_CODE (expression) == STATIC_CAST_EXPR
17562 || TREE_CODE (expression) == CONST_CAST_EXPR
17563 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17564 || TREE_CODE (expression) == CAST_EXPR)
17565 return dependent_type_p (TREE_TYPE (expression));
17567 /* The types of these expressions depends only on the type created
17568 by the expression. */
17569 if (TREE_CODE (expression) == NEW_EXPR
17570 || TREE_CODE (expression) == VEC_NEW_EXPR)
17572 /* For NEW_EXPR tree nodes created inside a template, either
17573 the object type itself or a TREE_LIST may appear as the
17575 tree type = TREE_OPERAND (expression, 1);
17576 if (TREE_CODE (type) == TREE_LIST)
17577 /* This is an array type. We need to check array dimensions
17579 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17580 || value_dependent_expression_p
17581 (TREE_OPERAND (TREE_VALUE (type), 1));
17583 return dependent_type_p (type);
17586 if (TREE_CODE (expression) == SCOPE_REF
17587 && dependent_scope_ref_p (expression,
17588 type_dependent_expression_p))
17591 if (TREE_CODE (expression) == FUNCTION_DECL
17592 && DECL_LANG_SPECIFIC (expression)
17593 && DECL_TEMPLATE_INFO (expression)
17594 && (any_dependent_template_arguments_p
17595 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17598 if (TREE_CODE (expression) == TEMPLATE_DECL
17599 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17602 if (TREE_CODE (expression) == STMT_EXPR)
17603 expression = stmt_expr_value_expr (expression);
17605 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17610 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17612 if (type_dependent_expression_p (elt))
17618 if (TREE_TYPE (expression) == unknown_type_node)
17620 if (TREE_CODE (expression) == ADDR_EXPR)
17621 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17622 if (TREE_CODE (expression) == COMPONENT_REF
17623 || TREE_CODE (expression) == OFFSET_REF)
17625 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17627 expression = TREE_OPERAND (expression, 1);
17628 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17631 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17632 if (TREE_CODE (expression) == SCOPE_REF)
17635 if (TREE_CODE (expression) == BASELINK)
17636 expression = BASELINK_FUNCTIONS (expression);
17638 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17640 if (any_dependent_template_arguments_p
17641 (TREE_OPERAND (expression, 1)))
17643 expression = TREE_OPERAND (expression, 0);
17645 gcc_assert (TREE_CODE (expression) == OVERLOAD
17646 || TREE_CODE (expression) == FUNCTION_DECL);
17650 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17652 expression = OVL_NEXT (expression);
17657 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17659 return (dependent_type_p (TREE_TYPE (expression)));
17662 /* Like type_dependent_expression_p, but it also works while not processing
17663 a template definition, i.e. during substitution or mangling. */
17666 type_dependent_expression_p_push (tree expr)
17669 ++processing_template_decl;
17670 b = type_dependent_expression_p (expr);
17671 --processing_template_decl;
17675 /* Returns TRUE if ARGS contains a type-dependent expression. */
17678 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17683 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
17685 if (type_dependent_expression_p (arg))
17691 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17692 expressions) contains any value-dependent expressions. */
17695 any_value_dependent_elements_p (const_tree list)
17697 for (; list; list = TREE_CHAIN (list))
17698 if (value_dependent_expression_p (TREE_VALUE (list)))
17704 /* Returns TRUE if the ARG (a template argument) is dependent. */
17707 dependent_template_arg_p (tree arg)
17709 if (!processing_template_decl)
17712 if (TREE_CODE (arg) == TEMPLATE_DECL
17713 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17714 return dependent_template_p (arg);
17715 else if (ARGUMENT_PACK_P (arg))
17717 tree args = ARGUMENT_PACK_ARGS (arg);
17718 int i, len = TREE_VEC_LENGTH (args);
17719 for (i = 0; i < len; ++i)
17721 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17727 else if (TYPE_P (arg))
17728 return dependent_type_p (arg);
17730 return (type_dependent_expression_p (arg)
17731 || value_dependent_expression_p (arg));
17734 /* Returns true if ARGS (a collection of template arguments) contains
17735 any types that require structural equality testing. */
17738 any_template_arguments_need_structural_equality_p (tree args)
17745 if (args == error_mark_node)
17748 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17750 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17751 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17753 tree arg = TREE_VEC_ELT (level, j);
17754 tree packed_args = NULL_TREE;
17757 if (ARGUMENT_PACK_P (arg))
17759 /* Look inside the argument pack. */
17760 packed_args = ARGUMENT_PACK_ARGS (arg);
17761 len = TREE_VEC_LENGTH (packed_args);
17764 for (k = 0; k < len; ++k)
17767 arg = TREE_VEC_ELT (packed_args, k);
17769 if (error_operand_p (arg))
17771 else if (TREE_CODE (arg) == TEMPLATE_DECL
17772 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17774 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17776 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17777 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17786 /* Returns true if ARGS (a collection of template arguments) contains
17787 any dependent arguments. */
17790 any_dependent_template_arguments_p (const_tree args)
17797 if (args == error_mark_node)
17800 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17802 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17803 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17804 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17811 /* Returns TRUE if the template TMPL is dependent. */
17814 dependent_template_p (tree tmpl)
17816 if (TREE_CODE (tmpl) == OVERLOAD)
17820 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17822 tmpl = OVL_CHAIN (tmpl);
17827 /* Template template parameters are dependent. */
17828 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17829 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17831 /* So are names that have not been looked up. */
17832 if (TREE_CODE (tmpl) == SCOPE_REF
17833 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17835 /* So are member templates of dependent classes. */
17836 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17837 return dependent_type_p (DECL_CONTEXT (tmpl));
17841 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17844 dependent_template_id_p (tree tmpl, tree args)
17846 return (dependent_template_p (tmpl)
17847 || any_dependent_template_arguments_p (args));
17850 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17854 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17858 if (!processing_template_decl)
17861 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17863 tree decl = TREE_VEC_ELT (declv, i);
17864 tree init = TREE_VEC_ELT (initv, i);
17865 tree cond = TREE_VEC_ELT (condv, i);
17866 tree incr = TREE_VEC_ELT (incrv, i);
17868 if (type_dependent_expression_p (decl))
17871 if (init && type_dependent_expression_p (init))
17874 if (type_dependent_expression_p (cond))
17877 if (COMPARISON_CLASS_P (cond)
17878 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17879 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17882 if (TREE_CODE (incr) == MODOP_EXPR)
17884 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17885 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17888 else if (type_dependent_expression_p (incr))
17890 else if (TREE_CODE (incr) == MODIFY_EXPR)
17892 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17894 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17896 tree t = TREE_OPERAND (incr, 1);
17897 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17898 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17907 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17908 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17909 no such TYPE can be found. Note that this function peers inside
17910 uninstantiated templates and therefore should be used only in
17911 extremely limited situations. ONLY_CURRENT_P restricts this
17912 peering to the currently open classes hierarchy (which is required
17913 when comparing types). */
17916 resolve_typename_type (tree type, bool only_current_p)
17925 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17927 scope = TYPE_CONTEXT (type);
17928 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17929 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17930 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17931 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17932 identifier of the TYPENAME_TYPE anymore.
17933 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17934 TYPENAME_TYPE instead, we avoid messing up with a possible
17935 typedef variant case. */
17936 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17938 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17939 it first before we can figure out what NAME refers to. */
17940 if (TREE_CODE (scope) == TYPENAME_TYPE)
17941 scope = resolve_typename_type (scope, only_current_p);
17942 /* If we don't know what SCOPE refers to, then we cannot resolve the
17944 if (TREE_CODE (scope) == TYPENAME_TYPE)
17946 /* If the SCOPE is a template type parameter, we have no way of
17947 resolving the name. */
17948 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17950 /* If the SCOPE is not the current instantiation, there's no reason
17951 to look inside it. */
17952 if (only_current_p && !currently_open_class (scope))
17954 /* If this is a typedef, we don't want to look inside (c++/11987). */
17955 if (typedef_variant_p (type))
17957 /* If SCOPE isn't the template itself, it will not have a valid
17958 TYPE_FIELDS list. */
17959 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17960 /* scope is either the template itself or a compatible instantiation
17961 like X<T>, so look up the name in the original template. */
17962 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17964 /* scope is a partial instantiation, so we can't do the lookup or we
17965 will lose the template arguments. */
17967 /* Enter the SCOPE so that name lookup will be resolved as if we
17968 were in the class definition. In particular, SCOPE will no
17969 longer be considered a dependent type. */
17970 pushed_scope = push_scope (scope);
17971 /* Look up the declaration. */
17972 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17974 result = NULL_TREE;
17976 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17977 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17980 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17981 && TREE_CODE (decl) == TYPE_DECL)
17983 result = TREE_TYPE (decl);
17984 if (result == error_mark_node)
17985 result = NULL_TREE;
17987 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17988 && DECL_CLASS_TEMPLATE_P (decl))
17992 /* Obtain the template and the arguments. */
17993 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17994 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17995 /* Instantiate the template. */
17996 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17997 /*entering_scope=*/0,
17998 tf_error | tf_user);
17999 if (result == error_mark_node)
18000 result = NULL_TREE;
18003 /* Leave the SCOPE. */
18005 pop_scope (pushed_scope);
18007 /* If we failed to resolve it, return the original typename. */
18011 /* If lookup found a typename type, resolve that too. */
18012 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
18014 /* Ill-formed programs can cause infinite recursion here, so we
18015 must catch that. */
18016 TYPENAME_IS_RESOLVING_P (type) = 1;
18017 result = resolve_typename_type (result, only_current_p);
18018 TYPENAME_IS_RESOLVING_P (type) = 0;
18021 /* Qualify the resulting type. */
18022 quals = cp_type_quals (type);
18024 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
18029 /* EXPR is an expression which is not type-dependent. Return a proxy
18030 for EXPR that can be used to compute the types of larger
18031 expressions containing EXPR. */
18034 build_non_dependent_expr (tree expr)
18038 /* Preserve null pointer constants so that the type of things like
18039 "p == 0" where "p" is a pointer can be determined. */
18040 if (null_ptr_cst_p (expr))
18042 /* Preserve OVERLOADs; the functions must be available to resolve
18045 if (TREE_CODE (inner_expr) == STMT_EXPR)
18046 inner_expr = stmt_expr_value_expr (inner_expr);
18047 if (TREE_CODE (inner_expr) == ADDR_EXPR)
18048 inner_expr = TREE_OPERAND (inner_expr, 0);
18049 if (TREE_CODE (inner_expr) == COMPONENT_REF)
18050 inner_expr = TREE_OPERAND (inner_expr, 1);
18051 if (is_overloaded_fn (inner_expr)
18052 || TREE_CODE (inner_expr) == OFFSET_REF)
18054 /* There is no need to return a proxy for a variable. */
18055 if (TREE_CODE (expr) == VAR_DECL)
18057 /* Preserve string constants; conversions from string constants to
18058 "char *" are allowed, even though normally a "const char *"
18059 cannot be used to initialize a "char *". */
18060 if (TREE_CODE (expr) == STRING_CST)
18062 /* Preserve arithmetic constants, as an optimization -- there is no
18063 reason to create a new node. */
18064 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
18066 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
18067 There is at least one place where we want to know that a
18068 particular expression is a throw-expression: when checking a ?:
18069 expression, there are special rules if the second or third
18070 argument is a throw-expression. */
18071 if (TREE_CODE (expr) == THROW_EXPR)
18074 if (TREE_CODE (expr) == COND_EXPR)
18075 return build3 (COND_EXPR,
18077 TREE_OPERAND (expr, 0),
18078 (TREE_OPERAND (expr, 1)
18079 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
18080 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
18081 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
18082 if (TREE_CODE (expr) == COMPOUND_EXPR
18083 && !COMPOUND_EXPR_OVERLOADED (expr))
18084 return build2 (COMPOUND_EXPR,
18086 TREE_OPERAND (expr, 0),
18087 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
18089 /* If the type is unknown, it can't really be non-dependent */
18090 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
18092 /* Otherwise, build a NON_DEPENDENT_EXPR.
18094 REFERENCE_TYPEs are not stripped for expressions in templates
18095 because doing so would play havoc with mangling. Consider, for
18098 template <typename T> void f<T& g>() { g(); }
18100 In the body of "f", the expression for "g" will have
18101 REFERENCE_TYPE, even though the standard says that it should
18102 not. The reason is that we must preserve the syntactic form of
18103 the expression so that mangling (say) "f<g>" inside the body of
18104 "f" works out correctly. Therefore, the REFERENCE_TYPE is
18106 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
18109 /* ARGS is a vector of expressions as arguments to a function call.
18110 Replace the arguments with equivalent non-dependent expressions.
18111 This modifies ARGS in place. */
18114 make_args_non_dependent (VEC(tree,gc) *args)
18119 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
18121 tree newarg = build_non_dependent_expr (arg);
18123 VEC_replace (tree, args, ix, newarg);
18127 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
18128 with a level one deeper than the actual template parms. */
18133 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
18134 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
18135 TYPE_DECL, get_identifier ("auto"), au);
18136 TYPE_STUB_DECL (au) = TYPE_NAME (au);
18137 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
18138 (0, processing_template_decl + 1, processing_template_decl + 1,
18139 TYPE_NAME (au), NULL_TREE);
18140 TYPE_CANONICAL (au) = canonical_type_parameter (au);
18141 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
18142 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
18147 /* Given type ARG, return std::initializer_list<ARG>. */
18152 tree std_init_list = namespace_binding
18153 (get_identifier ("initializer_list"), std_node);
18155 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
18157 error ("deducing from brace-enclosed initializer list requires "
18158 "#include <initializer_list>");
18159 return error_mark_node;
18161 argvec = make_tree_vec (1);
18162 TREE_VEC_ELT (argvec, 0) = arg;
18163 return lookup_template_class (std_init_list, argvec, NULL_TREE,
18164 NULL_TREE, 0, tf_warning_or_error);
18167 /* Replace auto in TYPE with std::initializer_list<auto>. */
18170 listify_autos (tree type, tree auto_node)
18172 tree init_auto = listify (auto_node);
18173 tree argvec = make_tree_vec (1);
18174 TREE_VEC_ELT (argvec, 0) = init_auto;
18175 if (processing_template_decl)
18176 argvec = add_to_template_args (current_template_args (), argvec);
18177 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18180 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
18181 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
18184 do_auto_deduction (tree type, tree init, tree auto_node)
18186 tree parms, tparms, targs;
18190 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
18191 with either a new invented type template parameter U or, if the
18192 initializer is a braced-init-list (8.5.4), with
18193 std::initializer_list<U>. */
18194 if (BRACE_ENCLOSED_INITIALIZER_P (init))
18195 type = listify_autos (type, auto_node);
18197 parms = build_tree_list (NULL_TREE, type);
18199 tparms = make_tree_vec (1);
18200 targs = make_tree_vec (1);
18201 TREE_VEC_ELT (tparms, 0)
18202 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
18203 val = type_unification_real (tparms, targs, parms, args, 1, 0,
18204 DEDUCE_CALL, LOOKUP_NORMAL);
18207 error ("unable to deduce %qT from %qE", type, init);
18208 return error_mark_node;
18211 /* If the list of declarators contains more than one declarator, the type
18212 of each declared variable is determined as described above. If the
18213 type deduced for the template parameter U is not the same in each
18214 deduction, the program is ill-formed. */
18215 if (TREE_TYPE (auto_node)
18216 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
18218 error ("inconsistent deduction for %qT: %qT and then %qT",
18219 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
18220 return error_mark_node;
18222 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
18224 if (processing_template_decl)
18225 targs = add_to_template_args (current_template_args (), targs);
18226 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
18229 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
18233 splice_late_return_type (tree type, tree late_return_type)
18237 if (late_return_type == NULL_TREE)
18239 argvec = make_tree_vec (1);
18240 TREE_VEC_ELT (argvec, 0) = late_return_type;
18241 if (processing_template_decl)
18242 argvec = add_to_template_args (current_template_args (), argvec);
18243 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
18246 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
18249 is_auto (const_tree type)
18251 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
18252 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
18258 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
18259 appear as a type-specifier for the declaration in question, we don't
18260 have to look through the whole type. */
18263 type_uses_auto (tree type)
18265 enum tree_code code;
18266 if (is_auto (type))
18269 code = TREE_CODE (type);
18271 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18272 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18273 || code == METHOD_TYPE || code == ARRAY_TYPE)
18274 return type_uses_auto (TREE_TYPE (type));
18276 if (TYPE_PTRMEMFUNC_P (type))
18277 return type_uses_auto (TREE_TYPE (TREE_TYPE
18278 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18283 /* For a given template T, return the vector of typedefs referenced
18284 in T for which access check is needed at T instantiation time.
18285 T is either a FUNCTION_DECL or a RECORD_TYPE.
18286 Those typedefs were added to T by the function
18287 append_type_to_template_for_access_check. */
18289 VEC(qualified_typedef_usage_t,gc)*
18290 get_types_needing_access_check (tree t)
18293 VEC(qualified_typedef_usage_t,gc) *result = NULL;
18295 if (!t || t == error_mark_node)
18298 if (!(ti = get_template_info (t)))
18301 if (CLASS_TYPE_P (t)
18302 || TREE_CODE (t) == FUNCTION_DECL)
18304 if (!TI_TEMPLATE (ti))
18307 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
18313 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
18314 tied to T. That list of typedefs will be access checked at
18315 T instantiation time.
18316 T is either a FUNCTION_DECL or a RECORD_TYPE.
18317 TYPE_DECL is a TYPE_DECL node representing a typedef.
18318 SCOPE is the scope through which TYPE_DECL is accessed.
18319 LOCATION is the location of the usage point of TYPE_DECL.
18321 This function is a subroutine of
18322 append_type_to_template_for_access_check. */
18325 append_type_to_template_for_access_check_1 (tree t,
18328 location_t location)
18330 qualified_typedef_usage_t typedef_usage;
18333 if (!t || t == error_mark_node)
18336 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
18337 || CLASS_TYPE_P (t))
18339 && TREE_CODE (type_decl) == TYPE_DECL
18342 if (!(ti = get_template_info (t)))
18345 gcc_assert (TI_TEMPLATE (ti));
18347 typedef_usage.typedef_decl = type_decl;
18348 typedef_usage.context = scope;
18349 typedef_usage.locus = location;
18351 VEC_safe_push (qualified_typedef_usage_t, gc,
18352 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
18356 /* Append TYPE_DECL to the template TEMPL.
18357 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
18358 At TEMPL instanciation time, TYPE_DECL will be checked to see
18359 if it can be accessed through SCOPE.
18360 LOCATION is the location of the usage point of TYPE_DECL.
18362 e.g. consider the following code snippet:
18369 template<class U> struct S
18371 C::myint mi; // <-- usage point of the typedef C::myint
18376 At S<char> instantiation time, we need to check the access of C::myint
18377 In other words, we need to check the access of the myint typedef through
18378 the C scope. For that purpose, this function will add the myint typedef
18379 and the scope C through which its being accessed to a list of typedefs
18380 tied to the template S. That list will be walked at template instantiation
18381 time and access check performed on each typedefs it contains.
18382 Note that this particular code snippet should yield an error because
18383 myint is private to C. */
18386 append_type_to_template_for_access_check (tree templ,
18389 location_t location)
18391 qualified_typedef_usage_t *iter;
18394 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
18396 /* Make sure we don't append the type to the template twice. */
18398 VEC_iterate (qualified_typedef_usage_t,
18399 get_types_needing_access_check (templ),
18402 if (iter->typedef_decl == type_decl && scope == iter->context)
18405 append_type_to_template_for_access_check_1 (templ, type_decl,
18409 /* Set up the hash tables for template instantiations. */
18412 init_template_processing (void)
18414 decl_specializations = htab_create_ggc (37,
18415 hash_specialization,
18416 eq_specializations,
18418 type_specializations = htab_create_ggc (37,
18419 hash_specialization,
18420 eq_specializations,
18424 #include "gt-cp-pt.h"